Accepted Abstracts

List of accepted abstract.

Preparation and Characterization of Silica Powder from Bamboo Leaves Ash (BLA)
Benito A. Baje[1], Felmer Latayada[1], Marlyn Villareal[2], Princess Juniere Peligro[2], Blessie Denise Chung[2], Kimiko Espiritu[1]
[1] College of Arts and Sciences, Caraga State University, Ampayon, Butuan City
8600 MIindanao, Philippines

Abstract

In an attempt to maximize waste product into useful material, the project primarily seeks to prepare silica from bamboo leaves ash (BLA) and to investigate its physical and chemical properties. Silica powder was prepared by precipitation method and characterized using various analytical techniques. Scanning Electron Microscopy(SEM) showed that the particle shapes were found to be non-uniform, globular, and agglomerated with dimensions ranges from 1um- 250um. Energy-Dispersive X-Ray (EDX) analysis also revealed the existence Si (46.12 wt%) and O (19.43wt%) peaks correspond to silica with C and traces amount of Cu, S, and Na. Fourier Transform Infra-Red Spectroscopy (FTIR) further support the presence of hydrogen bonded silanol group and siloxane group (Si-O-Si). In addition, X-Ray Diffraction (XRD) spectra also showed some characteristic peaks of silica compound. This study has introduced another renewable material as possible resource for silica production. BLA utilization from agricultural by-products into a high value material would not only be economical, but may possibly result into foreign exchange earnings and environmetal pollution control.

Keywords : Silica, XRD, SEM-EDX, FTRI

Time-Dependent Characterizations on Size Distribution of Fe₃O₄Nanocrystals by Using Transmission Electron Microscope
¹W. S. Chiu, ¹Saadah A. Rahman, ¹W.H. Abd. Majid, ¹Z. Aspanut, ²P. S. Khiew, ²T. K. Tan, ³S. Radiman, ³R. Abd-Shukor, ³M. A. Abd. Hamid, ³C. H. C
¹Low Dimensional Materials Research Centre, Department of Physics,Faculty of Science,University Malaya, 50603 Lembah Pantai, Kuala Lumpur, Malaysia
²Faculty of Engineering, University of Nottingham Malaysia Campus
³School of Applied Physics, Faculty of Science & Technology, UKM

Abstract

We report a green chemistry approach in the synthesis of Fe₃O₄ nanocrystals (NCs) by using palm-oil based carboxylic compound (oleic acid) as capping ligands. The Fe₃O₄ NCs were prepared by one pot reaction under non-hydrolytic approach. With the assistance of oleic acid that plays the role as effective capping-ligands, we showed that the Fe₃O₄ NCs, which are highly monodispersed in size and shape, can be synthesized by scrupulously controlling the reaction time. The diameter of Fe₃O₄ NCs can be tuned within the range of 4.0 – 18.0 nm and exhibit a very uniform morphology, which are spherical in shape. Current synthetic approach offers a cheap, environmentally-benign and excellent repeatability route in large-scale production of high-quality magnetic Fe₃O₄ NCs if compared to the preceding reports.

Keywords : Nanomaterial, Synthesis, Characterization, Fe₃O₄, Morphology, Magnetic, Transmission Electron Microscope

Characteristic Study Of Polyethylene Terephthalate (PET) used for Commercial Drinking Bottles under Ultraviolet (UV) Radiation by using a Solar Furnace
M.F.A. Aziz, T.L. Yap
Department Of Physical Sciences, Faculty of Science and Technology, Universiti M

Abstract

Polyethylene Terephthalate (PET) has long become part of our life. Research on the mechanical properties of PET under exposure to UV radiation is still lacking. Samples are taken from commercial drinking bottle with varying colours and brand. Samples SFC are sample with no colour present, while sample SFG are coloured in green. To increase the effect of UV radiation, a solar furnace is built with reflecting mirror and the UV lamp above it. This prevents any absorption by the environment and all UV radiation will only focus on the sample itself. Different duration is set for each sample. The duration of exposure starts from 0, 50, 100, 150, 200, and 250 hours. Parts of the samples are then taken to undergo tensile testing where properties such as force at break and Young’s Modulus are determined using M350-10CT Testometric. Another part of the samples are taken to be tested for its infra red absorbance using Thermo Nicolet Avatar 360 Spectrometer. Samples which have undergoes tensile test will be brought to the Scanning Electron Microscopy laboratory to be taken its surface morphology using the JEOL JSM-6360LA. Results obtained from the tensile test shows a drop in force at break but an increase value for Young’s Modulus. FTIR results came out with almost the all peak decaying with longer exposure to UV radiation. The C=O band especially, is observed to be decaying. SEM results also shows that the layers in the PET material start to loosen up after 250 hour of UV exposure.

Keywords : PET, Polyethylene Terephthalate, UV, solar furnace, commercial drinking bottles.

Effect of Fiber Loading on Properties of Thermoplastic Sago Starch/Kenaf Core Fiber Biocomposites
Norshahida Sarifuddin*, Hanafi Ismail* and Zuraida Ahmad^
*School of Materials and Mineral Resources Engineering,USM Engineering Campus,
^Department of Manufacturing and Materials Engineering, Faculty of Engineering,
International Islamic University Malaysia,P.O. Box 10, 50728 Kuala Lumpur,
Malaysia.

Abstract

A growing attention has been paid to the innovation of ecological products ushered by rising environmental concerns. As a natural polymer, thermoplastic sago starch has been regarded as an alternative material to petroleum based plastic owing to their availability, cost and biodegradability. In order to produce thermoplastic starch materials with enhanced structural and functional stability during use, kenaf fiber were incorporated as the reinforcing filler. In this work, thermoplastic sago starch (TPSS)/kenaf core fiber biocomposites were prepared at different fiber loading (0-35 wt. %) and the effects of fiber loading were analyzed by mechanical test, TGA, XRD, FTIR, SEM and water absorption behavior. The tensile mechanical analysis showed linear increase in strength and modulus upon increasing fiber content until it reaches an optimum at 30 wt. % fiber loading. Thermal stability of biocomposites was slightly improved by the incorporation of kenaf fibers into TPSS matrices. XRD and FTIR results indicated a change in functional group and crystallinity of the biocomposites. Moreover, the morphological studies of tensile fracture surfaces were evident to its interfacial adhesion properties. It is interesting to note that, water absorbed by the biocomposites was reduced by the addition of fiber, and seems the hydrophilic character was decrease especially for glycerol plasticized sample. The results obtained clearly illustrate for a given processing method and suitability of mix proportion, the properties of composite will be influenced by the interfacial bonding between fibers and matrices.

Keywords : Thermoplastic sago starch, Kenaf fiber, Biocomposites

Preparation of waste polystyrene- g- acrylic acid- co- starch superabsorbent hydrogel
Maryam Irani, Hanafi bin Ismail, and Zulkifli bin Ahmad
School of Materials and Mineral Resources Engineering,
USM Engineering Campus,
Universiti Sains Malaysia,
14300 Nibong Tebal,
Penang, Malaysia

Abstract

Superabsorbent hydrogels are a cross-linked network of hydrophilic polymer with a three-dimensional structure that can absorb, swell and retain a large amount of water or other aqueous fluids more than thousands of times their own weight. They have been used in different fields such as horticulture and agriculture, drug delivery system, coal dewatering, and sanitary goods. In this work, a type of superabsorbent from waste polystyrene foam (PS), acrylic acid (AA) and starch was prepared through emulsion polymerization using N, N-methylenebisacrylamide (MBA) as the crosslinker, benzoyl peroxide as the oil soluble initiator, and potassium persulfate as the water soluble initiator. The superabsorbent hydrogel was characterized by Fourier transform infrared spectroscope (FTIR), scanning electron micrograph (SEM) and thermo gravimetric analysis (TGA).The results confirmed the incorporation of acrylic acid and starch in the polystyrene chain. The swelling rate, water absorbency and water retention of the superabsorbent hydrogel were investigated. The highest capacity of water absorbency for the synthesized superabsorbent is 390 g H₂O/g sample in distilled water.

Keywords : superabsorbent hydrogel, waste polystyrene, water absorbency

Synthesis and characterization of Nano Silver Based Natural Rubber Latex Foam Materials
W.G. Indrajith Udayakantha Rathnayake
Ph.D Student, ,School of Materials and Mineral Resources Engineering,
Engineering Campus, University Sains Malaysia(USM)
Seri Ampangan, 14300, Nibong Tebal
Seberang Perai Selatan,
Pulau Penang,
Malaysia.

Abstract

Nanomaterials have been widely used in so many applications such as electronics, magnetics and optoelectronics, energy and catalytic, biomedicine, pharmaceuticals, clothing, cosmetics, and environmental detection and monitoring. Combination of nanomaterials with natural rubber has been investigated by many researchers in recent years, specially making composite materials with natural rubber and nanoparticles such as carbon nanotubes(CNT), nanosilica, nano sized clay materials(layered silicate), have become very popular and interesting research area. In the present work silver nanoparticles were adsorbed on natural rubber latex foam (NRLF) material by reducing Ag+ ions on the NRLF using tri-sodium citrate as the reducing agent. Then the morphology of resultant NRLF pieces was characterized by scanning electron microscope (SEM) and elemental analysis was done by Energy Dispersive X-ray (EDX) analysis. Particle size of silver nanocolloids of the reaction mixer and the shape of the silver nanoparticles were respectively analysis by particle size analyzer and Transmission Electron Microscope (TEM). The results clearly shows that the 50 nm size nano silver particles were adsorb on the modified NRLF and the shapes of silver nanoparticles in the reaction vessel were cubooctahedral.

Keywords : silver nanoparticles, natural rubber latex foam, SEM, EDX, TEM.

Obtaining good, believable geological analyses with an Electron Microprobe
Nur Iskandar Taib, Ros Fatihah Muhammad and Norishah Hashim
Geology Dept., Fac. Science,,
University of Malaya
50603 Kuala Lumpur
Malaysia

Abstract

Obtaining publishable geological analyses with an electron microprobe requires a thorough understanding and application of the technique, and an understanding of the materials being analyzed. In geology, electron microprobes are mainly used to determine the major and trace elemental composition of minerals (mainly silicates, but also sulfides and oxides). A unique feature of geological analysis is that compositions are often given in percent oxide, while the microprobe actually measures element concentrations. Analysis totals (after conversion to percent oxide) should approach 100% if the material being measured does not contain water, and should approach a theoretical maximum based on water content if it does. A low total is the mark of an inferior analysis, usually caused by a bad polish, coating, or calibration. A carbon coat is used to conduct electrons away from the beam site. A bad coat will cause charging (and low totals), an overly thick coat also causes low totals through energy absorption. Heavy metals, often used in electron microscopy, should NOT be used for elemental analyses – they absorb a great deal of beam energy and emit peaks which interfere with those being measured. Beam conditions (accelerating voltage, beam current and spot size) must be chosen so as not to damage the material being analyzed. Hydrated minerals such as micas, ones that contain sodium, and fragile materials such as volcanic glass can suffer beam damage, and must be analyzed using low voltages and currents, as well as diffuse beams. Calibration is crucial, and can be checked by running standards as samples. Standards should be cross-analyzed against each other. The choice of standards can be critical – while calibration can be done with pure elemental standards, calibrations should be checked using standards resembling the material being analyzed. With modern probes, calibrations can remain good for a period of time, but should be constantly checked.

Keywords : Electron microprobe geology microanalysis

Tensile, Swelling and Morphological Properties of Bentonite Filled Ethylene-Propylene-Diene Monomer (EPDM) Composites
M.Mathialagan
School of Materials and Mineral Resources Engineering
Engineering Campus, Universiti Sains Malaysia
Nibong Tebal, 14300 Penang
Malaysia

Abstract

Bentonite (Bt) was used as reinforcement in EPDM and the effect of Bt loading on tensile, swelling and morphological properties of EPDM/Bt composites were studied. The composites were prepared using a laboratory scaled two-roll mill with a varying Bt loading of 0 to 70 parts per hundred rubber (phr). Tensile strength, elongation at break (Eb), tensile modulus at 100% elongation (M100) and swelling properties of EPDM/Bt composites were all improved in comparison to the pristine EPDM. Optimum tensile and swelling properties of EPDM/Bt composites were obtained with incorporations of 50 phr Bt. The morphology of tensile fractured surface of EPDM/Bt composites observed under scanning electron microscope (SEM) reveals the good dispersion of Bt particles in EPDM matrix as well as good adhesion between Bt and EPDM. Greater interaction between Bt and EPDM were observed with addition of 50 phr Bt whereas agglomerations of Bt particles were observed with addition of 70 phr Bt into EPDM matrix.

Keywords : EPDM, Bentonite, Tensile properties, Swelling resistance, Scanning Electron Microscope

ELECTRON MICROSCOPIC OBSERVATION ON THE RETINA OF INDIGENOUS LOCAL GOAT
Alaa A. Sawad*, D.K.Sukar**, N.S.Al-Samarae***
*Department of Anatomy, College of Veterinary Medicine, University of Basrah, Ba
***Department of Anatomy, College of Veterinary Medicine, University of Baghdad,

Abstract

ABSTRACT The present study was initiated to described ultra structure of the retina of twenty eyes of clinical healthy goats by using transmission electron microscope revealed that the Bruch's membrane situated between the choroid and retina, it was composed of three layers , the basement membrane of choriocapillaris , collagen fiber layer and basement membrane of pigment cells. The pigment epithelial layer distinguished as one row of columnar epithelial cells connected together by desmosomes, this layer enriched by rods or oval shaped melanosomes. The rods and cones layer consist of a modified nerve cells composed of outer segment that contains a stack of flattened sac-like structures termed disks. The outer segment attached to the inner segment by ciliary stalk. The inner segment contain mitochondria in different forms, glycogen granules ,Ribosome , Microtubules ,rough and smooth endoplasmic reticulum with a number of vesicles and vacuoles. The cones are divided into single cones and double cones, which consists of main and accessory units.

Keywords : choriocapillaris,Ribosome , desmosomes

Antibacterial Activity of Synthesized Zinc Oxide Nanoparticles on Oral Microorganisms
Dasmawati Mohamad¹, Chong Boon Teh¹, Habsah Hassan², Shahrom Mahmud^3
1School of Dental Sciences, Universiti Sains Malaysia, Kubang Kerian,
²School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian
³School of Physics, Universiti Sains Malaysia, Penang, Malaysia

Abstract

Introduction: Advancement of research technology nowadays has realized synthesization of metal oxide at nano levels. Their physical and chemical properties are interesting as well as their antibacterial activity. Zinc oxide is widely use in health related product due to its high refractive index, good thermal, and UV-protection properties. Zinc oxide (ZnO) powder was also found to show marked antibacterial activity. Different types of zinc oxide powders were synthesized at School of Physics, Universiti Sains Malaysia namely white, pharma and gold.

Objective: In this present work, the objective of the study is to measure the antibacterial activity of the synthesized zinc oxide against 5 types of oral bacteria which are Streptococcus mutans, Staphylococcus aureus, Pseudomonas aeruginosa, Streptopcoccus sobrinus, and Lactobacillus salivarius.
Methods: All the three types of zinc oxide were prepared in the concentration of 10mM. Then were mixed with the bacteria suspension by pipetted it into the microtube. The suspension of zinc oxide powders with the oral bacteria was lawn onto tryptic soy agar (TSA). After 24 hrs incubation, the number of colony forming unit (CFU) on the agar plate were counted.
Results: From the studies, a significant reduction of growth of S. sobrinus and L. salivarius was seen after 24 hours exposure to all types of ZnO. Whereas for the S. mutans, P. aeruginosa, and S. aureus, the number of colony forming increased after 24 hours exposure.
Conclusion: In conclusion, study showed that zinc oxide shows bacteriostatic effect against S. sobrinus and L. salivarius but no effect on S. mutans, S. aureus, and P. aeruginosa.
Keywords :

Histopathological evaluation of skin wound in rabbits treated by systemic dexamethasone
Muhannad A. Kashmoola¹, Imad M.Al-Ani<sup>2

1</sup>Dep. of Oral Pathology and Oral Medicine,Kulliyyah of Dentistry
²Dep. of Basic Medical Sciences, Kulliyyah of Medicine
International Islamic University, Kuantan, Malaysia

Abstract

Background: Healing of all damaged tissues including skin wounds have an identical pattern and depends on numerous intrinsic and extrinsic factors, one of these factors is cortisone hormone.

Aim of study: The present study was designed to show the effect of dexamethasone on skin wound healing.
Materials and methods: Twelve rabbits were used, experimental group (7 rabbits) administrated 4 mg dexamethasone ten days prior to skin incision and control group (5 rabbits) had got skin incision. Biopsies were taken from two groups for histopathological evaluation.
Results: control group shows proper wound healing includes epithelial growth migration that brought the wound edges to be close. Granulation tissue underneath the epithelium show to fill the incision gap represented by collagen fibers and fibroblast cells. The experimental group shows failure of epithelial wound edges to close and to be approximately in contact with absence of rete ridges. The main bulk tissue filled the incision gap is thick granulation tissue. Inflammatory cell with congested blood vessels can be detected.
Conclusion: Prolonged use of dexamethasone or misuse of this drug impaired wound healing.
Keywords :

A Comparison of Mitochondrial Distribution in Different Developmental Stages of Vitrified Murine Embryos
Nor-Shahida AR¹, Razif D^1,2, Salina O¹, Froemming GRA¹ and Nor-Ashikin MNK^1
1Institute of Medical Molecular Biotechnology (IMMB), Faculty of Medicine, Universiti Teknologi MARA,
Kampus Sungai Buloh, Selangor, Malaysia,
²Faculty of Health Sciences, Universiti Teknologi MARA, Puncak Alam, Selangor, Malaysia

Abstract

Background: Mitochondria are essential cell organelles involved in a variety of cellular activities including ATP synthesis, intracellular calcium homeostasis and apoptosis. Mitochondria play an important role for certain cell functions and cell growth. Recently, it has been reported that there is an association between mitochondrial distribution in early embryonic development and cytoskeletal organization. However, information about the distribution of mitochondria in various embryonic developmental stages using Confocal Microscopy is still limited and remains unclear. Objectives: To study and to compare the effects of vitrification on mitochondrial distribution in various developmental stages of preimplantation murine embryos. Methods: A total of 50 mouse embryos were used. The distribution of mitochondria was analyzed by immunofluorescent staining. The embryos were flushed out at the 2-cell stage after superovulating with Pregnant Mare Serum Gonadotropin (PMSG) and human Chorionic Gonadotropin (hCG). Two-cell embryos were cultured in M16 medium to obtain embryos at the expected stages. The embryos were then cryopreserved by vitrification. After warming, the embryos were then fixed with 4% paraformaldehyde and stained with 4¡¯,6-diamino-2-phenylindole dihydrochloride (DAPI) and later permeabilized with 1% Triton-X in Phosphate Buffer Saline (PBS). After incubation in 1% Triton-X, the embryos were labeled with Mitotracker Red. The embryos were then washed with PBS and counterstained with DAPI. Finally, the embryos were mounted on slides, sealed and stored in the dark at 4¢ªC before being viewed and analyzed under the Confocal Laser Scanning Microscope. Results & Conclusion: This study clearly shows that vitrification causes highly significant changes in mitochondrial distribution as compared to non vitrified embryos (ANOVA p¡Â0.0001). The intensity of Mitotracker Red in non vitrified 2-, 4-, and 8- cell stages were higher than the vitrified embryos. The underlying cause for this change in mitochondrial distribution may be due to cell injury during vitrification, chemical toxicity of the cryoprotectant, ice crystal formation, fracture damage and osmotic swelling.

Keywords : Mitochondrial distribution, embryos, Confocal Laser Scanning Microscope

SERUM DEPRIVATION INDUCES APOPTOSIS IN CULTURED HUMAN BRONCHIAL SMOOTH MUSCLE CELLS
Salina Othman, Nor Shahida Abdul Rahman, Gabriele Ruth Anisah Froemming
Institute of Medical Molecular Biotechnology, Faculty of Medicine,
Jalan Hospital
47000 Sungai Buloh
Selangor Darul Ehsan
Malaysia

Abstract

Background:Bronchial smooth muscle cells (BSMC) play a central role in normal lung physiology by controlling airway contractility. During chronic airway diseases ie. COPD or asthma, BSMC undergo morphological changes which can lead to hyperplasia and hypertropy of the airways. Phenotype switching, from a contractile type to a synthethetic/proliferative type, is a shared feature of smooth muscle cells. Therefore we wanted to test the theory that serum withdrawal will induce a contractile phenotype in BSMC. Objectives: To develop a immunofluorescence staining protocol for BSMC and to study the changes in cell morphology after 1 hour and 24 hours culture in serum-free medium. Methods: BSMC were seeded at subconfluent density in two-wells chamber slide and after it were reached 80% confluence, the cells were incubated for 1 hour and 24 hours in SmBM complete medium with and without serum. Then, the cells were labelled with Dapi, Alexa Fluor 635 Phalloidin and Monoclonal Anti-alpha-tubulin-FITC. Finally the cells were observed under Confocal Laser Scanning Microscope and the images were analyzed using QWIN Software. Result & Conclusion: After 1 hour of serum deprivation, BSMC started to show morphological features characteristic of apoptosis, such as membrane blebbing, cellular shrinkage, nuclear condensation and fragmentation, followed by detachment from the two-well chamber slide after 24 hours of serum deprivation. Images analysis showed a decrease in Alexa Fluor 635 Phalloidin staining intensity of Actin and Monoclonal Anti-alpha-tubulin-FITC staining intensity of tubulin. In conclusion, BSMC in contrast to other smooth muscle cells can’t be converted to a contractile phenotype by serum withdrawal. Serum deprivation leads to apoptosis of BSMC as soon as one hour.

Keywords : Bronchial Smooth Muscle Cells, COPD, asthma, apoptosis, serum deprivation

Effect of trans-polyoctylene rubber (TOR) on Mechanical Properties and Morphology of Polypropylene/recycled acrylonitrile-butadiene rubber/Rice Husk Powder (PP/NBRr/RHP) Composites 
S.Ragunathan1., H. Ismail1, K.Hussin2.
1. School of Materials and Mineral Resources Engineering, Engineering Campus, Un
2. School of Environmental Engineering, Kompleks Pengajian Jejawi 3,Universiti M

Abstract

Polymer composites based on different ratios of PP (polypropylene) and recycled acrylonitrile butadiene rubber (NBR) with and without trans-polyoctylene rubber (TOR) as a compatibilizer were investigated. Five compositions of PP/NBRr/RHP (i.e. 100/0/15, 80/20/15, 70/30/15, 60/40/15 and 40/60/15) were prepared with constant TOR ratio at 10 phr. Results indicated mechanical properties of the PP/NBRr/RHP composites decreased with increasing NBRr content. However tensile strength and tensile modulus was found to be improved in TOR compatibilized composites. TOR was found to successfully make interaction with NBRr matrix and became a part of the composite network. Crosslinking density of compatibilized PP/NBRr/RHP composites were found to be higher than uncompatibilized composites. The morphological studies of the tensile fracture surface supported good interaction between PP/NBRr matrices and RHP in the presence of TOR.

Keywords : PP, NBRr, trans-polyoctylene (TOR), Mechanical Properties

Processing Characteristics and swelling behaviour of trans-polyoctylene rubber(TOR) as compatibilizer on Polypropylene/recycled acrylonitrile-butadiene rubber/Rice Husk Powder (PP/NBRr/RHP) Composites
S.Ragunathan1., H. Ismail1, K.Hussin2.
1. School of Materials and Mineral Resources Engineering, Engineering Campus, Un
2. School of Environmental Engineering, Kompleks Pengajian Jejawi 3,Universiti M

Abstract

Effect of trans-polyoctylene rubber(TOR) as compatibilizer on different ratios of PP (polypropylene) and recycled acrylonitrile butadiene rubber (NBRr) were investigated. Five compositions of PP/NBRr/RHP (i.e. 100/0/15, 80/20/15, 70/30/15, 60/40/15, 50/50/15 and 40/60/15) were prepared with constant TOR ratio at 10 phr. Results indicated the processing characteristic of the PP/NBRr/RHP composites decrease with NBRr content due to increase molten viscosity of composites during mixing. However swelling and water absorption characteristics was found to be improved in TOR compatibilized composites. TOR was found to successfully make interaction with NBRr matrix and became a part of the composite network to further inhibit oil and water absorption into the composties. The morphological studies of the tensile fracture surface supported good interaction between PP/NBRr matrices and RHP in the presence of TOR.

Keywords : PP, NBRr, trans-polyoctylene (TOR), processing characteristics, swelling.

Crack-free BCP coating on 316L stainless steel medical implants through 30 second electrophoretic deposition
Asam M. A. Abudalazez, Shah Rizal Kasim, Azlan Ariffin and Zainal Arifin Ahmad
School of Materials and Mineral Resources Engineering Engineering Campus Univer

Abstract

Abstract In the present study, Electrophoretic deposition (EPD) technique was applied to obtain BCP coating on medical metal implants in ethanol at constant deposition voltages 20, 30 and 50 V for 30 second. The medical grade 316L stainless steel substrates were 25×10×1.2 mm in dimension. After deposition, surface of coatings before and after the sintering were investigated using scanning electron microscopy (SEM), energy dispersive spectrometry (EDX) and phase purity of the coating material was investigated by X-ray diffraction (XRD). The results of this study revealed that among various voltages and temperatures during 30sec which are used all the samples are crack-free, and by increasing applied voltage and temperature during EPD coating, roughness and thickness increases and leads to the formation of rough and thick coatings.

Keywords : Electrophoretic deposition (EPD) Biphasic calcium phosphate (BCP) 316L stainless steel Temperature Voltages

Surface Morphology of bioceramic bovine bone and freeze dried bovine pericardium by Electron Microscope and Infinite Focus Measurement: A comparative study
Adam, Z., Rusidah, M. Y., Firdaus, A. R., Hawani, A. A., Suzina, S. A. H.
Tissue Bank, School of Medical Sciences, Health Campus, Universiti Sains Malaysi

Abstract

The challenge to get more information in observation of surface morphology on biomaterial by using electron and optical micrsocope are increased by the year.The aim of this study was to compare the imaging methods used in surface morphology observation of bioceramic bovine bone and freeze dried bovine pericardium. The bioceramic bovine bone and freeze dried bovine pericardium were observed by Tabletop Microscope (TM), Field Emission Scaning Electron Microscope (FESEM) and Infinite Focus Measurement device (IFM). For FESEM, the samples were coated with gold. Observation using FESEM on bioceramic bovine bone and freeze dried bovine pericardium improved imaging quality with respect to contrast and charging effect. More detail information of porous structure on bioceramic bovine bone and collagen architecture on freeze dried bovine pericardium were acquired. TM uses low voltage and high chamber pressure shows the better quality in the case of severely charging effect. The small depth of focus of an optical system with vertical scanning in IFM provide surface texture of roughness information. In conclusion, the combination of FESEM and IFM in microscopic observation of bioceramic bovine bone and freeze dried bovine pericardium provide the better quality imaging and acquired more information.

Keywords : Surface Morphology, Bioceramic bovine bone, freeze dried bovine pericardium, electron microscope, InfiniteFocus measurement

The Effects of Tensile Properties, Swelling Test and Morphology of Recycled Polyethylene (rPE) From Wire Industry with Ethylene-Propylene Diene Terpolymer (EPDM) Blends
 Lokman H.I., H. Ismail, N.Z. Noriman, H.W. Woon
School Of Materials Engineering,
Kompleks Pengajian Jejawi 2,
02600 Arau,
Perlis, Malaysia

Abstract

In this study waste polyethylene from wire industry was melt blended with ethylene-propylene diene terpolymer (EPDM) in different ratio by using a Haake Rheomix at 180°C and 50 rpm were prepared. The characterization such as stabilization torque, tensile properties, swelling test and morphology were examined. The results indicated that, at a similar PE content, rPE/EPDM blends exhibited higher tensile strength, Young’s modulus and stabilization torque but lower elongation at break than vPE/EPDM blends. Swelling test revealed that rPE/EPDM blends have better oil and toluene resistance than vPE/EPDM blends. The scanning electron microscopy (SEM) on the tensile fracture surface of rPE/EPDM blends designated rougher surface with flow lines are encountered in rPE/EPDM blends compare to vPE/EPDM blends means that a higher energy is needed to cause catastrophic failure compare to vPE/EPDM blends.

Keywords : vPE, rPE, stabilization torque, tensile properties, swelling test, morphology analysis

The Effects of Electron Beam Irradiation on Natural Weathering Test of Styrene Butadiene Rubber/Recycled Acrylonitrile-Butadiene Rubber (SBR/NBRr) Blends
A. A. Azrem, N.Z. Noriman, H. Ismail
School Of Materials Engineering,
Universiti Malaysia Perlis (UniMAP),
Kompleks Pengajian Jejawi 2,
02600 Arau,
Perlis, Malaysia

Abstract

The effects of natural weathering test on irradiated and unrirradiated styrene butadiene rubber/recycled acrylonitrile butadiene rubber (SBR/NBRr) blends were investigated. The SBR/NBRr blends were prepared at 95/5, 85/15, 75/25, 65/35 and 50/50 blend ratio with and without the presence of polyfunctional monomer, trimethylolpropane triacrylate (TMPTA). It can be observed that, after 6 months exposure, the tensile properties and their retention (tensile strength, elongation at break and tensile modulus) of irradiated SBR/NBRr blends show lower value than unirradiated SBR/NBRr blends particularly when having 25, 35 and 50 phr of NBRr in the blends. This was due to excessive crosslink occurring with TMPTA at 40kGy together with the degradation in SBR phase occurred at longer exposure periods. The scanning electron microscopy (SEM) on the exposed surface showed that the imbrittlement of the irradiated SBR/NBRr blends particularly at 50/50 blend ratio indicated a weak interfacial adhesion occurred, therefore the blends is more susceptible to degradation.

Keywords : SBR/NBRr blends, electron beam irradiation, tensile properties retention, scanning electron microscopy

Effect of Cutting Parameters on the Surface Morphology of MWCNT Reinforced Epoxy Composite using End-Milling Process
G. Harii Krishna Rao, M.N.M. Ansari
College of Engineering, Universiti Tenaga Nasional, 43000 Kajang, Selangor D. E

Abstract

In this paper, the preparation and casting of sample composite, machining parameters and Scanning electron microscopy (SEM) of MWCNT reinforced Epoxy composites were discussed. Structurally, MWCNTs consist of multiple layers of graphite superimposed and rolled in on themselves to form a tubular shape. Three properties of MWCNTs’ are specifically interesting for the industry which are the electrical conductivity (as conductive as copper), their mechanical properties such as strength (up to 15 to 20 times stronger than steel and 5 times lighter) and their thermal conductivity (same as that diamond and more than 5 times that of copper). Dispersion of MWCNTs’ with epoxy resin were stirred with magnetic stirrer. MWCNT epoxy composite was cured at 50 0C for four hours to form a Rigid MWCNT nano-composite. MWCNT epoxy composite formed by casting method using rectangular pocket milled Aluminum mould. The effect of machined parameters on MWCNT Epoxy composite displays different surface structure under SEM with control of 3 major parameters of spindle speed, feed rate and depth of cut. Scanning electron microscopy (SEM) shows various surface morphology of the composite with controlled machined parameters under CNC end-milling process. The most dominant factor that affects the quality of surface roughness is feed rate which had the strongest influence followed by cutting speed and last by depth of cut. The surface roughness appears to be almost linear increasing function of feed rate and decreasing function of cutting speed. Thus, the best optimize level of surface roughness were feed rate at 10 mm/min and spindle speed at highest level of 1750 rpm. Also, high level of 0.8 mm or low levels of 0.4 mm for depth of cut are preferred.

Keywords :

SEM Studies on n-HA/PVA Scaffolds for Bone Tissue Replacement 
S. M.Md. Nainar¹, Shahida Begum¹, Bashir Mohamad¹, Robert A.Shanks^2
1Mechanical Engineering Department, College of Engineering,
Kajang 43009 Selangor, Malaysia
²School of Applied Sciences, RMIT University
Melbourne, VIC 3000

Abstract

The main characteristics of the biomimetic composites by which the mineralized hard tissue like substances are formed are its porosity, biocompatibility with the body tissues, mechanical strength and rigidity. Porous scaffold containing 10-30 wt% nano-hydroxyapatite (n-HA) and 90-70 wt% polyvinyl alcohol (PVA) was prepared by casting method and investigated by universal testing machine (UTM) for its tensile and compressive strength. Morphology of the fractured surface is analyzed under scanning electron microscopy (SEM). The results show that n-HA particles disperse homogeneously in the PVA matrix. The porous scaffold has not only macropores but also micropores on the walls of macropores. The porosity and compressive strength of scaffold are studied. The porous structure provides a good microenvironment for cell adherence, growth and proliferation. The n-HA/PVA composite scaffold can be satisfied with the basic requirement for tissue engineering, and has the potential to be applied in repair and substitute of human menisci of the knee-joint and articular cartilage. It also can be replaced for tissue malfunction due to fracture of bones by various traumas and/or natural ageing. Surgical treatment frequently requires implantation of a temporary or permanent prosthesis, which is still a challenge for orthopaedic surgeons, especially in the case of large bone defects.

Keywords : Biomimetic Composites, Compressive Strength, Tissue Engineering, n-HA/PVA Scaffolds

Synthesis and characterization of SnO2 nanoparticles/graphene
Lim Hong Ngee
Center for Ionics University of Malaya
Faculty of Science
University of Malaya
Kuala Lumpur

Abstract

SnO2 nanoparticles/graphene nanocomposite was synthesized by a facile microwave method. The x-ray diffraction pattern and x-ray photoelectron spectroscopy analysis revealed a merger between the two components. The field emission scanning electron microscope images revealed that the graphene sheets were decorated with SnO2 nanoparticles with an average size of 10 nm. The nanocomposite modified glassy carbon electrode showed excellent enhancement of electrochemical performance when interacting with mercury (II) ions in potassium chloride supporting electrolyte.

Keywords : electrochemistry, electron microscope, graphene, nanocomposite, tin oxide

STUDIES OF DEGRADATION AND DRUG RELEASE PROPERTIES OF CHITOSAN CONTAINING NALTREXONE FOR THE TREATMENT OF DRUG ADDICTION
S.M.Ghani1,2*, K. Noorsal1, Mansor, S.M.2
1Advanced Materials Research Centre (AMREC), SIRIM Berhad,Lot 34, Jalan Hi-Tech
Kulim Hi-Tech Park, 0900 Kulim, Kedah. Malaysia
2Centre For Drug Research,Universiti Sains Malaysia, 11800 Penang. Malaysia

Abstract

Naltrexone is a long-acting opiate antagonist that blocks opiate-induced euphoria, a state associated with pleasure and anaesthetic-like feeling. It is an approved treatment for heroin addiction and alcoholism. This work investigated the chitosan microspheres as a potential carrier for naltrexone. Chitosan is a biodegradable natural polymer with great potential for pharmaceutical application due to its biocompatibility, high charge density, non-toxicity and mucoadhesion. Chitosan microspheres was first prepared with the formation of gel which was obtained by interaction of low molecular counterions of polyphosphate pentabasic (TPP). Blank and drug loaded chitosan microspheres undergo degradation in phosphate buffer saline at 37^oC, pH of 7.4 and agitated at 100 rpm for 30 days. The degradation behaviour of the chitosan microspheres was revealed through the mass loss and water uptake, polymer thermal changes through Differential Scanning Calorimetry (DSC), changes in the development of functional groups through Fourier Transform Infrared (FTIR) ), changes in polymer morphology through X-ray Diffraction (XRD) analysis and changes of the polymer microstructure through the Variable Pressure Electron Microscopy. Drug release pattern of naltrexone is monitored through the UV- Spectrophotometer at 281 nm, in which kinetic release of the model drug will be generated.

Keywords : Chitosan microspheres, degradation, drug release, naltrexone

DETECTION OF ADENOVIRUS TYPE 5 INFECTION USING MICROSCOPIC ANALYSIS
Sayang Baba¹, Sugeng Triwahyono², Samsul Draman³, Abdul Rahim Hussein4 and Salehhuddin Hamdan^1
1 Faculty of Biosciences and Bioengineering, Universiti Teknologi Malaysia, Johor
² Institute Ibnu Sina for Fundamental Science, Universiti Teknologi Malaysia, Johor
³ Department of Community Health and Family Medicine, Kuliyyah of Medicine, Inte
⁴ Department of Hematology, School of Medical Sciences, Universiti Science Malay

Abstract

Adenoviruses have been used widely in clinical trial as a gene transfer vectors. Since surface Coxsackie and Adenovirus receptor (CAR) expression as their primary receptor and its limiting step for the success of therapeutic gene transfer, therefore the aim of this study is to clone and express human CAR-receptor into CAR-negative CHO cell lines. Here, we reported that we have successfully cloned human CAR tagged with enhanced green fluorescent protein (EGFP) into CHO cells. Successfully engineered CHO-CAR-EGFP cells were directly viewed by the presence of green colour under the inverted fluorescent microscope. Further investigation on biological function of CAR was observed by infecting wild type adenovirus serotype 5 and observation was demonstrated using cytopathic effect and confocal microscope. The significance of these approaches would infer that the strategy could be implemented to analysis adenovirus infection.

Keywords : Coxsackie and Adenovirus receptor (CAR), CHO, Enhance Green Fluorescent Protein (EGFP), cytopathic effect, confocal microscope.

Electrical and Flexural Performance of Hybrid Silver Filled Epoxy Composites for Electronic Applications
Suriati Ghazali, Mariatti Jaafar*, Azizan Aziz
School of Materials and Mineral Resources Engineering
Engineering Campus, Universiti Sains Malaysia
14300 Nibong Tebal, Seberang Prai Selatan
Penang, Malaysia

Abstract

The present articles reported the synergistic effect of hybridization of two types of silver fillers, e.g. silver nanoparticles (100 nm) and silver flakes (4-8 µm). The percentage of silver flakes (F) to silver nanoparticles (NP) has been varied from 100F:0NP, 75F:25NP, 50F:50NP, 25F:75NP and 0F:100NP. All samples were characterized in term of electrical and flexural properties. The dispersion and fracture mechanism of hybrid composite were observed by scanning electron microscope (SEM) on fracture surface of the samples when it subjected to load. It is found that combination of these two fillers improve the dispersion of the conductive fillers in polymer composites and subsequently enhance the flexural performance of the materials.

Keywords :

The performance of SEM for viewing cellular structure of human amniotic membrane
 Z. Kamalia¹, A.H. Suzina¹, Yusof, N², H Asnah^2
1Tissue Bank,
School of Medical Sciences,
Health Campus,
Universiti Sains Malaysia,
16150 Kubang Kerian Kelantan, Malaysia

Abstract

Scanning Electron Microscopy (SEM) has been applied to image the sample surface including biological samples. The aim of this study was to identify the ability of SEM to observe cellular structure of preserved irradiated human amniotic membrane (HAM). HAM was obtained from the selected human placenta. The samples were processed and preserved by air drying (ADHAM) and in glycerol (GPHAM). The HAMs were sterilized by gamma irradiation at 0 kGy, 15 kGy, 25 kGy and 35 kGy. After fixation process, the samples were stored in acetone until the next stage. HAMs were observed under three different types of SEM: Environmental SEM (ESEM), Variable Pressure SEM (VPSEM) and High Vacuum SEM (HVSEM). The physical structure of the ADHAM and GPHAM was differed through different types of SEM. HVSEM was found to have better contrast and resolution for observing HAM compared to other SEM. At × 10000 magnifications, HVSEM was able to show the four basic patterns of HAM which covered with microvilli and the intercellular channels were clearly observed in both ADHAM and GPHAM. HVSEM has the best performance in assessing the changes in cell morphology of preserved HAM following irradiation at different doses. This study revealed that the types of SEM influences the images of preserved irradiated HAM.

Keywords : HAM, ESEM, VPSEM, HVSEM, Cellular structure

HYDROTHERMAL GROWTH OF ZnO NANORODS MORPHOLOGY STUDY
W. A. Dhafina, E. A. Ghapur, and S. Hasiah

Department of Physical Sciences,
Faculty of Science and Technology,
University Malaysia Terengganu,
21030 Kuala Terengganu.Terengganu, Malaysia

Abstract

ZnO nanorods have got attention in research since it’s first reported in ultraviolet lasing. A lot of effort has been devoted to the synthetic methodologies for one-dimensional ZnO nanostructures development. There are various techniques to produce ZnO nanorods described in the literatures. Solution approaches to ZnO nanorods is interesting because of their low growth temperatures and good potential for scale-up. Usually, the hydrothermal method involved two-steps which are seeding and dipping the conducting glass substrates in ZnO precursors step. The size (diameter and length) of nanorods can be tuned by changing the dipping process parameters such as temperature, duration, precursor’s concentration and etc. In this work, result showed that ZnO nanorods was successfully growth with average diameter of 89 +- 1 nm and average length of 140 +- 1 nm that are going to be used in fabrication of tandem solar cell.

Keywords : nanorods, hydrothermal and solar cell

APOPTOTIC INDUCING EFFECT OF TRIORGANOTIN, TRIBUTYLTIN P-NITROCINAMATE ON HT-29 COLECRECTAL ADENOCARCINOMA CELL
Abdah Md Akim, Tan Ji Wei
Department of Biomedical Sciences
Universiti Putra Malaysia
43400 Serdang
Selangor
Malaysia

Abstract

Organotin compound are chemical compound based on tin with hydrocarbon substituent. Many organotin complexes are being studied in the anticancer therapy to see their cytotoxicity and selectivity towards cancer cells. The general aim of this study was to investigate the anti-proliferative effect of tributyltin p-nitrocinnamate on the HT-29 colorectal cancer cell. The triorganotin complexes cytotoxicity towards the colon cancer cells had been studied and its IC50 value obtained had been compared with the standard drug of 5-florouracil. During the used of the cell proliferation assay (MTT), the cancer cells were treated with drug concentration range from 1x10-6 mg/ml to 1x10-5 mg/ml to obtain its IC50 value. Besides that, the treated cancer cells were also incubated in a 24, 48 and 72 hours period to witness its cytotoxic effect in a time-dependent manner. Apart from that, viewing of the treated HT-29 cell morphology and its quantification using acridine orange and propidium iodide assay through the fluorescence microscope had also been done. The purpose of this assay is to detect any apoptotic morphology present from the treated cancel cells. In order to investigate whether the triorganotin complexes were able to induce the apoptotic pathway, the human caspase-9 ELISA kit had been used to quantify the caspases-9 protein expression of the treated HT-29 cells. Result of the MTT assay showed that the IC50 value of tributyltin p-nitrocinnamate was 6.0x10-6 ± 0.18 mg/ml in a 24 hours period. Hence, three concentrations of 3.5x10-6 mg/ml, 6.0x10-6 mg/ml and 8.5x10-6 mg/ml had been chosen to treat the cancer cell in the staining assay for 24 hours. During the AO/PI staining assay, apoptotic morphology of the treated cell such as membrane blebing and apoptotic bodies present which is the hallmark of the apoptosis where able to be detected and the number of viable cancer cell decreases from 58.07 ± 0.88%, 49.10 ± 0.07% and to 22.65 ± 0.60% as the selected drug concentration increases. Result from the human caspase-9 ELISA test indicated that the tributyltin p-nitrocinnamate was able to trigger the apoptosis through caspase-9 dependent pathway. The quantity of the caspase-9 protein increases from 50 ± 2.83 ng/ml for none treatment to 111 ± 4.24 ng/ml for 3.5x10-6 mg/ml of drug used and finally to 189 ± 4.24 ng/ml for the flask that was treated with the IC50 value. In conclusion, the triorganotin compound of tributyltin p-nitrocinnamate was able to cause anti-proliferative effect on the HT-29 cell through activation of the caspase-9 dependent apoptotic pathway.

Keywords : organotin, cancer

THE MORPHOLOGICAL STUDY OF NEEDLE-SHAPED RAPHIDES IN PANDANUS SPECIES
Z. Eshak, H. F. Mohsin and I. Abdul Wahab
Faculty of Pharmacy, Universiti Teknologi MARA,
42300 Puncak Alam, Selangor Darul Ehsan, Malaysia

Abstract

The examination of calcium oxalate (CaC₂O₄.H₂O) in Pandanus plant (family: Pandanaceae) was conducted to observe this calcite formation by utilising Confocal Laser Scanning Microscopy (CLSM). The function of this stable mineral was reviewed earlier as a defence for herbivory and calcium transport. The research materials consisted of the leaves and roots of eight Pandanus species, namely P. amaryfollius (locally known as pandan wangi), P. conoideus, P. dubius (locally known as mengkuang), P. leram, P. pygmaeus, P. sanderi, three unidentified Pandanus (including a variety of P. tectorius, P. utilis and P. sanderi) and an imported commercialised P. amaryfollius’ leaves, packed in tea bags. From the micrographs, needle-shaped raphides were detected, instead of the other four commonly reported types of crystals. Some samples contain the non-whiskers needle characteristics, in contrast to the one reported for the other Oceanian Pandanus dubius. In summary, the adapted extraction methodology by employing 70% ethanol in the current work was appropriate for this morphological study.

Keywords : raphides, pandan, confocal laser scanning microscope

Mechanical, Thermal and Morphological Properties of Nano-ZnO Filled PP/EPDM Blends
I. Nurul Hidayah and M. Mariatti
School of Materials and Mineral Resources Engineering, USM Engineering Campus,
14300 Nibong Tebal, Penang.

Abstract

Blends of Polypropylene (PP) and Ethylene Propylene Diene Monomer (EPDM) at various ratios consist of nano-zinc oxide (ZnO) were prepared and their mechanical, thermal, and morphological properties were studied. Addition of EPDM to PP resulted in a significant decrease in tensile strength and tensile modulus. As expected, the elongation at break increased as a result of EPDM flexibility. The incorporation of 2 vol% nano-ZnO into the blend gave a slight increase in the tensile strength and tensile modulus value but had notably decreased the elongation at break. Through TGA, it was found that EPDM based composite showed a better thermal stability compared to PP based and the blends. Morphological studies on the cryogenic-fractured surface of the samples revealed the incompatibility of the blends through the presence of EPDM cavitations.

Keywords : polypropylene, EPDM, nanofillers, mechanical, thermal, morphology

The Effect of Graphene Oxide on the Mechanical, Electrical and Morphological Properties of Graphene/Epoxy Nanocomposite
Low Hann Sen¹, M.N.M. Ansari¹, Shahida Begum¹, S.H.S.Zein^2
1College of Engineering, Universiti Tenaga Nasional, Kajang 043009 Se
²School of Chemical Engineering, Universiti Sains Malaysia, Nibong Te

Abstract

In this paper, the characterization of mechanical, electrical and morphological properties of graphene oxide/Epoxy composites were discussed. The combination of macroscopic flexibility and stiffness of graphene oxide is a result of a unique interlocking tile arrangement of the nanoscale graphene oxide with epoxy cast sheets. The use of graphene oxide in polymer composites displays excellent mechanical and electrical properties that make it potentially suitable for fuel cell and structural composite applications. Graphite was modified by Hummer method to form the graphene oxide. Dispersion of graphene oxide in water was extracted and mixed with epoxy resin. Homogenous grapheme oxide/epoxy resin was cured at 80 ⁰C for four hours to form grapheme/ epoxy nanocomposite monoliths. Graphene oxide/epoxy composite formed by casting method exhibits a percolation threshold of ~0.2 wt% per cent for room temperature electrical conductivity, and has a volume conductivity of ~30x10 ^-8 S m ^-1, sufficient for some electrical applications. Scanning electron microscopy (SEM) shows the fractured surface morphology of the graphene oxide/epoxy nanocomposites.

Keywords :

The effect of dynamic vulcanization on thermal properties of high density polyethylene / natural rubber / thermoplastic tapioca starch
Mohd Kahar
School of Materials and Mineral Resources Engineering,
14300, Nibong Tebal, P.Pinang

Abstract

Effect of dynamic vulcanization on thermal of high density polyethylene (HDPE) / natural rubber (NR) / thermoplastic tapioca starch (TPS) blends were studied. The ratio between HDPE/NR was fixed at 70/30 and blended with TPS in varying concentrations 5% -30% using a Haake Rheomix 600 mixer. Two series of HDPE/NR/TPS blends were prepared, i.e. unvulcanized and vulcanized system. The measurements from dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA), proved the effectiveness of dynamic vulcanization in improving the compatibility between HDPE/NR – TPS blends. TGA analysis shows that in the presence of sulphur curative system, the blends have better thermal stability as compared to unvulcanized blends. The storage modulus which is reflected to the blend stiffness also increases after vulcanized, indicated the improvement in HDPE/NR – TPS interaction.

Keywords : HDPE/NR/TPS, dynamic vulcanization, thermal properties

The effect of dynamic vulcanization of high density polyethylene / natural rubber / thermoplastic tapioca starch blends on physical, mechanical and morphological properties
Mohd Kahar
School of Materials and Mineral Resources Engineering,
14300, Nibong Tebal, P.Pinang

Abstract

Blending of high density polyethylene (HDPE), natural rubber (NR) and thermoplastic tapioca starch (TPS) have been studied. Two series having 5 – 30 wt% TPS were prepared: (a) unvulcanized blends (control) and (b) dynamic vulcanized HDPE/NR/TPS blends. The composition of HDPE/NR was constant and fixed to blend ratio of 70/30. SEM morphology showed that TPS particle are homogenously dispersed and well embedded in vulcanized HDPR/NR matrix. The SEM micrographs show an agreement with the tensile strength and elongation at break value. The tensile strength exhibit significant improvement when HDPE/NR/TPS blends were vulcanized using sulphur curative system. The enhancement in tensile properties is attributed to the crosslink reaction within the NR phase.

Keywords : HDPE/NR/TPS, dynamic vulcanization, tensile properties, phase morphology.

Ultra structural changes in the transitional mucosa adjacent to carcinoma of descending colon
Reshma.M.Ansari, Ye Tun
International Islamic University Malaysia Kuantan, Malaysia.

Abstract

Colorectal cancer is the fourth most common cancer worldwide, with about 677,000 deaths each year. According to the Gale Encyclopedia of Medicine, of all of the major cancers, only colorectal cancer can be prevented by screening and this measure is nearly 100% effective in preventing cancer development. However it still continues to be associated with high mortality rates, primarily because of the failure to detect neoplastic lesions at an early stage. The term transitional mucosa (TM) was coined by Filipe in 1969 to describe alterations in the morphology and mucin histochemistry of the large intestinal mucosa immediately adjacent to colorectal adenocarcinomas. TM has two main features- elongation and branching of the mucosal crypts with dilatation of goblet cells and alteration in the ratio of sulphomucins to sialomucins as assessed by the high-iron diamine/Alcian blue technique. The retained transitional mucosa at the margins of the resection appears to correlate with tumor recurrence and a poorer survival in patients who have undergone radical resection. Hence the TM is considered as an important prognostic marker for patients with large bowel cancer following radical resection. The average extension of TM was confined to a zone 2cm of a carcinoma. 3 samples from a colorectal surgical specimen were taken to study the extent of the transitional changes in them. They were selected approximately 2cms, 5cms and 8cms from the tumor site. The tissues were then processed and viewed under SEM to gauge the extent of the transitional changes. This would help us to determine a new margin of resection in patients with colorectal cancer to reduce recurrences.

Keywords : Colorectal Cancer,Transitional Mucosa,Intestinal Mucosa,Morphology

EFFECT OF WEATHERING CYCLES OF KENAF CORE FILLER FILLED HIGH DENSITY POLYETHYLENE COMPOSITE
Ashraf Rohaniza Asari ^1,2 and Razaina Mat Taib ^1,2
1 School of Materials and Mineral Resources
² Integrated Laboratoty for Advancement of Research in Engineering an
Kampus Kejuruteraan,
Universiti Sains Malaysia, 14300 Nibong Tebal,
Pulau Pinang

Abstract

In this study, combined water/ultraviolet (UV) and only ultraviolet (UV) weathering performance of kenaf core filler (KCF) filled high density polyethylene (HDPE) composites was studied. Maleated polyethylene (MAPE) was used as coupling agent to improve the incompatibility between the hydrophilic fillers and the hydrophobic matrix. Compounding process was run using a Haake Rheomixer machine at 160°C and 50 rpm. Filler loading was fixed at 50% and the coupling agent content was 5 wt% based on filler dry weight. Compression molding was done after compounding process to produce sample for characterizations. The samples were weathered in xenon- arc weathering chamber for 500, 1000, 1500, 2000, 2500, and 3000 hours. Composites were exposed to radiation with and without water spray. Colorimetry, flexural test and SEM were employed to measure the color change, flexural properties and surface morphology after weathering. Increasing exposure time increased the color change and lightness of the composites. Samples exposed to UV light and water spray experienced greater color change than samples exposed to UV light alone. Samples exposed to UV light and water spray also shown greater decreased in flexural properties than samples exposed to UV light only. Flexural strength and flexural modulus of composites decreased by 42% and 35% for UV light and water spray exposure while 14% and 10% for UV light exposure after 3000 hours of exposure time. SEM micrograph showed severe surface crack after 3000 of exposure. Similarly composite samples exposed to both UV light and water spray showed greater surface roughness (more microcracks) than those exposed to just UV light.

Keywords : Kenaf core fillers, wood - plastic composites, weathering, color change, flexural properties and surface morphology

Influence of Cu Particle Size on Densification and Microstructure of W-(10-30)wt.% Cu Composite Powders Processed by Liquid Phase Sintering Mechanism
M.A. Selamat, N. Abd Majid, F. Ismail and F.S. Mohamed Fadzil
Structural Material Program
Advanced Materials Research Centre (AMREC), SIRIM Berhad,
Lot 34, Jalan Hi-Tech 2/3, Kulim Hi-Tech Park, 09000 Kulim, Kedah

Abstract

Fabrication of W-Cu near net-shapes has become an important issue today due to their unique properties which make them suitable for a wide variety of applications, especially in electrical and electronic industries. In this work, W-Cu composite powders containing micron and sub-micron size of 10, 20 and 30wt.%Cu were processed by powder metallurgy route via liquid phase sintering mechanism. The experimental powders were cold compacted, cold isostatic pressed (CIPped) and sintered in nitrogen-based atmosphere (95%N2-5%H2) in the sintering range 1000-1300C. After sintering in nitrogen-based atmosphere, the composites fabricated sintered at 1000-1150C show inhomogeneous microstructure due to formation of large globules of copper and tungsten agglomerates, while the structure of samples sintered at 1200-1300C reveals the existence of copper with the tungsten grains, forming interconnected microstructure. The sub-micron W-Cu composite powders exhibits high sinterability, relative density of near 98% of the theoretical was achieved for W-Cu compacts sintered at 1200C. At this optimum sintering temperature, the sintered of sub-micron W-Cu part showed homogeneous microstructure and good mechanical properties.

Keywords : Sub-micron powder, W-Cu composites, Liquid Phase Sintering

Machinability and Surface Morphology of Halloysite Nanotube (HNT)-Aluminium/Epoxy Composite Board for Rapid Tooling Applications
Pang Jing Shen, M.N.M. Ansari
College of Engineering
43000 Kajang, Selangor D. E

Abstract

A new rapid tooling approach based on high-speed CNC machining had made possible by the recent development of particulate-filled hybrid polymer composite materials. The epoxy composite material, for example Aluminum-filled epoxy, which is suitable for high-speed CNC milling of injection molds and forming dies, does not have further studies on its machinability characteristic. Hence, the studies on different fillers for epoxy composite material responses to machining parameters and tool geometry are required to optimize the surface characteristics and accuracy of the machined parts. The main objectives of this study is to investigate on the composition (wt%) of HNT which gives the best machinability characteristics when mixed with Al-epoxy composite and the comparison between Aluminium filled epoxy composite and a pure HNT/epoxy composite. The machinability of the materials are quantified in terms of resultant cutting forces, the surface roughness, workpiece break-out (or “chip out”) and tool wear. The cutting forces were measured using a force dynamometer whereas surface roughness on the machined area was measured using surface profilometer. The morphology of each machined surface created using CNC end-milling process were analyzed under Scanning Electron Microscopy (SEM). The workpiece break-out in each epoxy composites were studied using optical microscope. From the results, HNT with aluminum filled epoxy composite shows the best machinability characteristics. In surface roughness, HNT with Al/epoxy composites show better results compared to Al/epoxy composites.

Keywords : Halloysite Nanotube (HNT), epoxy composite, Machinability, Surface roughness, Cutting Forces, SEM.

REVISITING THE STOMATAL STRUCTURE IN PANDANUS SPECIES
A. K. Ishak, R. Omar, Z. Eshak, H. F. Mohsin and I. Abdul Wahab
Faculty of Pharmacy, Universiti Teknologi MARA,
42300 Puncak Alam, Selangor Darul Ehsan, Malaysia

Abstract

A study of stomatal structure in Pandanaceae that was conducted nearly half a century ago was followed with great interest. The pioneering findings were obtained by the illustrations made from camera lucida drawings. In this paper, the result of a recent study of the systematic anatomy of the Pandanaceae, specifically Pandanus amaryfollius, is presented. An advanced technique utilizing Scanning Electron Microscopy (SEM) is based on a fresh leaves specimen. Initial condition includes avoiding nocturnal procedure. As published earlier, five stomatal classes were established. From the literature review, these experimental stomata were categorised as Class 1, the unspecialized stomata, out of five classes. When compared with a modern microscopical examination of Pandanus candelabrum, the stomatal population are also more numerous on the lower surface. However, the presence of calcium oxalate crystals could not be identified. Finally, this work could provide enhanced view of the stomatal apparatus in other Pandanus species, and hopefully in due course, would be as comprehensive as the previous efforts.

Keywords : stomata, Pandanus, scanning electron microscope

Improved Wear and Thermal Cycling Performance of Alumina 3%wt Titania Plasma Spray Coating by Varying Selected Process and Machine Parameters Setting
Abdul Rahim Mahamad Sahab, Nor Hayati Saad
B18, Structural Materials Programme, Advanced Materials Research Centre
SIRIM Berhad
No. 1, Persiaran Dato Menteri, Section 2
P.O. Box 7035
40700 Shah Alam
Selangor, Malaysia

Abstract

Plasma spray coating is a versatile thermal spray to produce coating onto substrate especially for ceramic material. It produces high temperature of plasma flame and is able to melt any ceramic powder or wire and sprayed toward metal substrates to produce high adhesion strength coating. In order to develop high adhesion strength bonding many parameters and variables have to be considered such as selection of bond coat material, substrate surface preparation and type of coating material influenced the coating properties. In this study, alumina 3%wt titania and nickel 5%wt aluminium feedstock were used as a top coat and bond coat coating and sprayed onto metal substrate by using Praxair Plasma Spray System with SG-100 gun. The coating samples were developed by varying selected parameters setting which were current, powder flow rate and stand-off-distance to produce good adherence coating bonding. The coated samples were tested for the mechanical test (adhesion strength and hardness) performance and finally analysed for wear behaviour and thermal cycle test. The Scanning-Electron-Microscope (SEM) was used to observe the coating layer morphologies. The analysis results showed that the powder flow rate, current and stand-off-distance have significant influence on the properties and performance improvement of ceramic coating.

Keywords : plasma sprays, ceramics coating, wear behaviour, thermal cycle, process and machine parameters.

Investigation on Wear Characteristics of Tungsten Carbide and TiAlN-Coated Tungsten Carbide Insert in Turning Carbon Steel
 R.J. Talib, H,M. Ariff, A.M. Zaharah, M. F. Fazira
AMREC, SIRIM Berhad
34 Jalan Hi-Tech 2/3
Kulim Hi-Tech Park
09000 Kulim
Kedah

Abstract

Cutting tool inserts were subjected to turning of carbon steel at cutting speeds of 120 mm/min, depth of cut of 0.5 mm and feed rate of 0.06 mm/rev. Flank wear was measured using stereo microscope and morphology of worn surfaces was observed using field emission scanning electron microscope after 60 minutes turning of carbon steel workpiece. Machining test results show that the TiAlN coating has improved tool life as compared with uncoated cutting insert due to higher hardness and lower friction coefficient. Microstructural changes on the worn surfaces revealed that the failure mechanisms in operation during turning were abrasive, adhesive and thermal.

Keywords : TiAlN-coated insert, turning, wear, SEM, CNC

The development and characterization of HDPE-Silica Sand Nanoparticles Composites
Tahir Ahmad*, Othman Mamat
Mechanical Engineering Department,
Universiti Teknologi PETRONAS,
Bandar Seri Iskandar,
31750 Tronoh,
Perak, Malaysia

Abstract

The development of polymeric nanocomposites has invoked much interest in recent years. These nanofillers have great affect on the mechanical, barrier, electrical and thermal properties of base polymers. The present study aims to develop High Density Polyethylene (HDPE) matrix composite reinforced with silica sand nanoparticles. The silica sand nanoparticles with average particle size of less than 100nm was produced by several stages of ball mill and heating combinations. HDPE matrix composites with 5, 10, 15 and 20 wt.% of silica sand nanoparticles were developed through internal mixing with HDPE and then using compression moulding machine. Physical properties, mechanical behaviour, thermal behaviour and microstructure were studied. It was observed that physical properties increased with increasing trend of silica sand nanoparticles in HDPE. Mechanical properties increased with an optimum value of 15 wt. % of silica sand nanoparticles in HDPE. DSC analysis shows a reduction in degree of crystallinity of the composites with increasing trend of silica sand nanoparticles.

Keywords :

Study on the Purification of CdSe Nanoparticless Solution by Repeated Precipitation
Khatijah A. Yaacob and Jason D. Riley
School of Materials and Mineral Resources Engineering,
University Science Malaysia,
Engineering Campus,
14300 Nibong Tebal
Pulau Pinang

Abstract

In this work, we study the qualitative and quantitative of the colloidal TOPO capped CdSe with 4.0 nm in diameter after several times precipitation from toluene. The fresh solution after the preparation is not pure, there are some excess free ligands in the solution such as TOPO, cadmium acetate, selenium, HDA and TDPA unbound to the nanoparticles (1) and also impurities from the solvent. The purification process of the fresh solution involves addition of methanol to the fresh solution to drive particle flocculation, followed by centrifugation of the solution. In this process CdSe quantum dots precipitate to the bottom of the centrifuge tube leaving a clear solution (supernatant). The supernatant was removed and toluene was added to the CdSe powders to resuspended the particles in toluene. This procedure is referred as 1x wash. Repetition of the redissolution / reprecipitation process was continued for 2x, 3x, 4x and 5x. Transmission electron microscopy, was carried to study the quality of the CdSe nanoparticles after several purification process and inductively couple plasma-atomic emission spectroscopy was used to performed elemental analysis on the ratio of Cd to Se and phosphorous containing ligand bound to the surface.

Keywords : CdSe nanoparticles, precipitation, purification, transmission electron microscopy

Characteristic and Analysis of Stainless Steel 304 after Running Potential Dynamic in Reactor Pool TRIGA MARK II
Zaifol Samsu, Muhammad Daud, Siti Radiah Mohd Kamarudin, Nur Ubaidah Saidin, Azali Muhammad, Mohd Shaari Ripin, Rusni Rejab, Mohd Shariff Sattar
Blok 34, Kumpulan Teknologi Bahan
Bahagian Teknologi Industri
Agensi Nuklear Malaysia
43000 kajang, Selangor

Abstract

This paper presents the results of a morphology observation on the Stainless Steel 304 in reactor pool TRIGA Mark II after running potentiodynamic. Material composition of the stainless steel was measured using Spark Emission Spectroscopy (SES) machine. Potentiodynamic tests were carried out on the Stainelss Steel sample with 1 cm2 exposure surface area in demin water reactor pool. Polarization plots showed the alloys suffered from low activation attack by aggressive ions containing in Demin Water reactor pool. The morphology on the polarized stainless steel showed general attack with little amount of hemispherical isolated deeper pits on the stainless steel. The result showed that the of present small amount of alloying elements such as chromium in the stainless steel played a major role in activation breakdown and given surface of the alloy become passive and eventually corrosion resistance to the aggressive anions present in seawater.

Keywords : Potentio Dynamic, Surface Morphology, Corrosion, Corrosion Resistance

Comparative study of the effects of treatment methods on the performance of Kenaf (Hibiscus canabinus) Fibre as Brake Pad base material
N.O. Namessan, J.N. Maduakob, and Ugheoke, B.I.
Department of Agronomy,
Taraba State University, Jalingo
Nigeria.

Abstract

Asbestos fibre has been used as the traditional base material in brake pads manufacture, but due to its health hazard, non-renewability, cost, non-biodegradability and difficulty in processing, its replacement has been sought. This paper reports the effects of some processing techniques- mercerization, acetylation and semi-carbonisation on the performance of Kenaf (Hibiscus canabinus) fibres, which are considered biodegradable, cost effective, renewable and user friendly. These treated fibres have been investigated, as a possible base friction material for brake pad production. The performance evaluation results indicated that the crude fibre based kenaf brake pads have high percentage of porosity and water absorption capacity with an average value of 38 % and 0.067 g respectively than all the samples investigated. Mercerized samples have high values of Rockwell hardness of 101 HR on the average, while semi-carbonized samples had high thermal conductivity with an average value of 0.6215 W/m. K, exhibiting minimum wear loss of 1.588 mm. Generally, brake pad samples produced from semi-carbonized fibres yielded the best quality (with minimum wear loss of 1.588mm, Dynamic coefficient of friction of 0.3948, and thermal conductivity value of 0.6215W/m.K during performance evaluation.

Keywords : Kenaf fibres, fibre processing methods, performance evaluation in brake pad application

Microstructure and Tribological Properties of TiAlN Coated HSS Cutting Tool Insert
M.F. Fazira, M.A. Selamat, A.M. Samsiah, A.M. Zaharah, R.J. Talib
AMREC SIRIM Berhad
Lot 34 Jalan Hi-Tech 2/3
Kulim Hi-Tech Park
09000 Kulim
Kedah

Abstract

The reliability and lifetime of surfaces of tools and machine parts is, in most cases, influenced by wearing character. The microstructure and tribological properties of high speed steels inserts made by powder metallurgy deposited with thin coating is measured and studied. TiAlN coating was deposited on the steel surface by PVD process. The tribological pin-on-disc test was used for the determination of coating properties in terms of friction and wear rates. The wear tracks and microstructure of the coated and coated samples were observed by scanning electron microscopy (SEM) and EDAX. The formation of quality PVD coating depends on surface preparation and morphology of substrate. It is found that the TiAlN coatings has significantly improved the performance of the cutting tools in terms of friction and wear rates.

Keywords : PVD, TiAlN, Morphology, Tribology, HSS inserts

Electrochemical performance of MCMB/Li_{4Ti5O12 composite electrode as anode materials for lithium ion battery}
M. I. Ishak *, H. Hasan, N. Alias, A. Mat, K. S. Sulaiman, M.A. Sulaiman, S. M. Hasanaly
Electrochemical Material Programme, Advanced Material Research Centre,
Lot 34, Jalan Hi-Tech 2/3, Kulim Hi-Tech Park, 09000 Kulim, Kedah

Abstract

MCMB graphite is incorporated into lithium titanate (Li₄Ti₅O₁₂) to enhance the electronic conductivity of the Li₄Ti₅O₁₂ anode material during electrochemical cycling process thus improving the anode’s rate capability. The influence of difference wt. % (20, 40, 50, 60 and 80) addition of MCMB on the electrochemical performance of the MCMB/Li4Ti5O12 composite as anode material in li-ion cells is examined in this study. Each blend of composites was prepared by mechanically ball milling Li4Ti5O12 with MCMB for 1hour at 100 rpm. X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FE-SEM) are applied to characterize the phase structure and morphology of the composite produced. The MCMB/Li₄Ti₅O₁₂ composite produced displayed a spherical shape with an average particle size distribution of 20-30 µm. Electrochemical cycling of the cells showed that MCMB/Li₄Ti₅O₁₂ with 50 wt. % delivered the highest capacity of about 213 mAh/g when compared with the pristine Li₄Ti₅O₁₂ at 181 mAh/g.

Keywords : MCMB graphite, Li4Ti5O12, anode material, electrochemical performance

The Effect of Process Parameters on Elemental Distribution of Sn-3.5Ag-1.0Cu Lead-free Solder Prepared via Powder Metallurgy Method
N. A. Ab Ghani base¹, a, I. Yahya 1, b, Mohd Salleh M.A.A 2, c, Hamidi Abd Hamid 1, d, Zainal Ariffin Ahmad 3, e, Ramani Mayappan 1, f

Keywords :

Improvement of Mechanical Properties of Recycled High Density/Natural Rubber/Kenaf Powder Biocomposites by Using Maleated Natural Rubber as a Coupling Agent
Xuan Viet Cao¹, Hanafi Ismail¹, Azura A. Rashid¹, Tsutomu Takeichi², Thao Vo-Huu^3
1 School of Materials & Mineral Resources Engineering, Engineering Ca
² School of Materials Science, Toyohashi University of Technology, Ja
³ Faculty of Materials Technology, Ho Chi Minh University of Technolo

Abstract

Kenaf powder was incorporated into recycled high density polyethylene (rHDPE)/natural rubber (NR) blend using an internal mixer at 165^oC and rotor speed of 50 rpm. The rHDPE/NR ratio was fixed at 70/30. The tensile strength and elongation at break of the composites decreased, while the tensile modulus increased with increasing filler content. The maleic anhydride grafted natural rubber (MANR) was prepared and used as an effective coupling agent. The addition of MANR improved all tensile properties of rHDPE/NR/KP biocomposites. Scanning electron microscopy of the tensile fracture surface of the composites showed a better filler-matrix adhesion which was an evidence for the enhanced tensile properties in the presence of MANR.

Keywords : recycled high density polyethylene, natural rubber, biocomposites, kenaf, maleated natural rubber

Apoptosis versus necrosis: electron microscopy observations of cell death events in Influenza A virus and Chikungunya virus induced infection of cultured cells 
TS Saraswathy, AS Santana Raj, O Khairul Azuan, R Aida Suhana, A Izan Shahrina and S Zainah
Virology Unit
Institute for Medical Research
Jalan Pahang
50588 Kuala Lumpur
Malaysia
Tel: 603-26162671, Fax: 603-26938094, E-mail: saras@imr.gov.my

Abstract

The potential outcome of a virus infection at cellular level is the death of the host cell, since viruses are obligate intracellular parasites. Cell death may occur by a variety of complex mechanisms but the two most commonly described is necrosis and apoptosis, which differ both morphologically and biochemically. Necrosis is a passive, degenerative process which is a result of gross injury to the cell, while apoptosis or programmed cell death is an active process driven by the cell. In this study, we have illustrated the cell death events of Influenza A virus infection in MDCK cell culture and Chikungunya virus infection in BHK-21 cell culture using transmission electron microscopy.

Keywords : Apoptosis, necrosis, virus, transmission electron microscopy

The Growth of AlN Cap Layer on Silicon Substrate by Plasma-Assisted MBE
Mohd Zaki Bin Mohd Yusoff
Semiconductor Physics

Abstract

Aluminum nitride (AlN) has the widest direct band gap (~6.1 eV) among the III-nitrides and possesses outstanding properties such as high temperature stability, high thermal conductivity and deep ultraviolet (DUV) transparency.In this paper, we investigated growth of AlN cap layer on silicon (Si) substrate (111) by using plasma assisted molecular beam epitaxy (PA-MBE) system with GaN/AlN as a buffer layer.The structural and optical characteristics of the sample have been characterized by using scanning electron microscopy (SEM), high resolution X-ray diffraction (HR-XRD), Raman spectroscopy and photoluminescence (PL).PL spectrum of the sample has shown sharp and intense band edge emission of GaN with the absence of yellow emission band, indicating good crystal quality of the sample.The silver (Ag) metal contact was then deposited on the sample followed by thermal treatment at 400^oC, 500^oC, 600^oC and 700^oC, respectively.Treated sample at 700^oC showed good spherical Ag islands on sample compared to the other treated samples. The structural quality and crystallinity level of Ag islands on AlN cap layer were also examined by using XRD measurement.

Keywords : III-Nitrides, AlN, MBE, Silicon, Silver, Ag islands

DENSIFICATION PROFILE OF HYDROXYAPATITE-ALUMINA BIOCERAMICS THROUGH MICROSCOPY 
M., Fatimah, A. R., Toibah, and A., Shaaban
Department of Engineering Materials, .
Faculty of Manufacturing Engineering, Universiti Teknikal Malaysia Melaka (UTeM)
Hang Tuah Jaya, 76100 Durian Tunggal, Melaka, Malaysia

Abstract

Hydroxyapatite (HA) bioceramics have excellent biocompatibility but has fragility drawbacks. Addition of alumina reinforces the mechanical performance of HA dense bioceramics. This study aims to analyze the densification profile of HA with varying amounts (5 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt% and 50 wt%) of alumina additions using physical and chemical preparation methods. The effects of sintering temperature (800-1300°C) sintered for 2 h were also observed. Microstructure, composition and bulk density were investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope-energy dispersive spectroscopy (SEM-EDS). The hardness of dense ceramic was measured through Vickers hardness test (HV) to examine the mechanical property. The results confirmed the significant character of alumina as reinforcing agent and densification behaviour at different sintering temperature.

Keywords : hydroxyapatite, alumina, densification, sintering, microstructure

Rapid Nucleation of Ti₃SiC₂ Nanolaminates Synthesized via Tungsten Inert Gas Method
Mohamad Johari Abu, Julie Juliewatty Mohamed, Zainal Arifin Ahmad
Universiti Sains Malaysia, School of Materials and Mineral Resources Engineering

Abstract

The purpose of this study is to observe the rapid nucleation of Ti₃SiC₂ nanolaminates synthesized via TIG method. The mixture of Ti, Si and C powders was dry-mixed using high speed mixer with ball to powder ratio 10:1 for 1 hour and compacted into 13 mm diameter and 5 mm height of pellets. The pellet was arced at fixed 90 A arcing current for 5 s soaking time. The phase presents and its composition was analyzed by X-Ray Diffractometry (XRD) performed by Retvield refinement method. The surface morphology and elemental compositions of arced samples was analyzed by a field emission scanning electron microscopy (FESEM) coupled with EDX analysis. The result shows that sample arced at 90 A arcing current and 5 s soaking time is sufficient enough to produce 72.6 wt% of Ti3SiC2. The micrographs analysis was revealed that the rapid formation of Ti3SiC2 nanolaminates was nucleated on the surface of TiC grain. EDS analysis shows that the atomic ratio of Ti:Si:C was close to 3:1:2, which indicates to Ti3SiC2. The typically appearances of Ti3SiC2 grain is elongated platelets with grain size 1 – 14 µm. The average size of Ti₃SiC₂ nanolaminates layer with obtained in elongated platelets is ~88 nm, respectively.

Keywords : Composite, Carbide, Nuclear application, TIG, Ti₃SiC₂

A microscopic analysis of recent lithified limestones from a present-day platform, east of Sabah, Malaysia.
Nor Syazwani Zainal Abidin, Bernard J. Pierson, Ani Aiza Asha'ari
Geoscience and Petroleum Engineering Department,
Universiti Teknologi PETRONAS,
Bandar Seri Iskandar,
31750 Tronoh, Perak

Abstract

A detailed petrographic study of lithified limestone horizons from a number of present-day carbonate platforms of the Tun Sakaran Marine Park in the Celebes Sea, east of Sabah, Malaysia, aims at determining the diagenetic history and the origin of the cements that have lithified carbonate sediments. Conventional microscopy is used to classify the carbonate rock, determine its components and depositional texture and identify the cements in order to understand the diagenesis and paleoenvironments. High resolution images produced with a scanning electron microscope (SEM) shows a 3Dimentional rendition of the cements and allows the identification of crystal morphology and mineralogy. This study focused on 3 types of lithified limestone, i.e. beachrock, submarine hardgrounds and exposed reef limestone. Beachrocks were sampled on the islands of Sibuan and Maiga. The texture of the beachrocks is consistently a coarse-grained, skeletal-dominated and moderately sorted grainstone, suggesting a high-energy depositional environment (wave swash). Micritic envelopes, mostly brown in colour, formed after deposition. The grainstone was then cemented by fibrous aragonite, forming needle-like crystals. Individual crystals of fibrous aragonite vary in length. Fibrous cement form rims of equal thickness around the grains. The fibrous needles are occasionally longer in intraparticle pore spaces than around the grains. This clear dominance of aragonite cements implies cementation in marine waters. A submarine hardground was sampled in a lagoonal environment, north of Maiga Island. Texture, composition and diagenesis are similar to that of the beachrock. One specific feature of the submarine hardground is the common presence of borings by specialized mollusks (lithophaga) after cementation. The walls of the borings are clearly erosional and are devoid of cement. The exposed reef limestone was sampled on the islands of Selakan and Sebangkat. The limestone is rich in corals and represents a reef, now elevated 3 to 5 meters above its original position. Packstone and boundstone are the dominant textures and consist of bivalve, brachiopod, gastropod, coral fragments, benthic foraminifera mililoid, red foram Homoterma Rubrum, and Acopora sp. calcareous green and red algae. The diagenetic alteration starts with the formation of a micritic envelope. It is followed by dissolution of aragonite. The raised reefs are mainly cemented by low Mg-calcite cement, characteristic of freshwater vadose environment of diagenesis. In this study, microscopy was an essential tool in determining the nature and origin of the cements that lithified carbonate sediments.

Keywords : Petrographic, Diagenesis, Beachrock, Hardground, Aragonite, Reef, Low Mg-calcite

EFFECT OF SUBSTRATE TEMPERATURE ON THE GROWTH OF AL THIN FILM ON SILICON (100) SUBSTRATE.
Zulhelmi Alif Abdul Halim¹, Muhamad Azizi Mat Yajid¹ and Riyaz Ahmad M. Ali^2
1 Department of Materials, Faculty of Mechanical Engineering, Universiti Teknolo
² Microelectronic and Nanotechnology, Shamsudin Research Centre, Faculty of Elec

Abstract

Aluminum films on Si (100) substrate were deposited by RF magnetron sputtering. The effect of substrate temperature on the microstructural morphologies of the films was characterized by using field emission scanning electron microscope/energy dispersive x-ray (FESEM-EDX) and atomic force microscopy (AFM). X-ray diffraction (XRD) was used to characterize the phases and crystallite size of Al films. The grains are preferentially oriented along the (111) planes at 200oC and it changes into (110) orientation from 300oC. FESEM analysis found that the films become more uniform and compactness as the deposition temperature increased from 200°C to 300°C. As the temperature increases, AFM result show that the mean roughness of the films decreases due to the surface diffusion of adatoms and the atomically-smooth surfaces are obtained at 300oC. However, increases in temperature led to increases in crystal size.

Keywords : RF magnetron sputtering, Microstructural characterization, Grain growth, Epitaxy.

Classification of Hand-Like Trichome Types in Selected Species in Pentace (Tiliaceae)
 Noraini. T, Nurhanim, M. N. and Chung R. C. K
School of Environmental and Natural Resources Science,
Faculty of Science and Technology,
Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor.

Abstract

A comprehensive survey and descriptions on the trichome types were conducted using scanning electron microscopy on 18 taxa of Pentace of Tiliaceae in Malaysia and Borneo. Attention was paid to their types, shape and density. This study has shown significant taxonomic value in the trichome types in species of Pentace from Malaysia and Borneo especially in the presence of hand-liked trichome type. The hand-like trichome types is a brand new type of trichomes found in higher plants and were found in Pentace acuta, Pentace eximia, P. floribunda and P. strychnoidea. This type of trichomes has been classified into three categories based on its morphological characteristics ie: epicalyx hand-liked trichome, fan- shaped hand-liked trichome and palmatifid hand-liked trichomes. This study has succeed revealed a brand new type of trichome and proved that trichome evidence could possibly be applied as additional data in identification of species in Pentace.

Keywords :

HIGH THROUGHPUT SYNTHESIS OF GOLD NANORODS FROM MULTISEGMENTED NANOWIRES
Kok Kuan Ying, Ng Inn Khuan and Nur Ubaidah Saidin
Malaysian Nuclear Agency
Bangi
43000 Kajang
Selangor Darul Ehsan
Malaysia

Abstract

Multisegmented nanowire is a useful configuration for high throughput and cost effective production of nanostructures for various device and functional applications. This work explores the novel capability of multisegmented nanowires in the synthesis of gold nanorods with various aspect ratios. Multisegmented Au/Ni nanowires were obtained by direct sequential deposition of Au and Ni segments, with different predetermined lengths, into the pores of porous anodized alumina template via template-assisted electrodeposition. By selectively removing the Ni segments in the nanowires after growth, high-yield of pure gold nanorods of predetermined dimensions was successfully obtained. The advantages of this method are that it saves processing time, production costs and materials requirements. It can also be easily scaled up for mass production. Gold nanorods are useful materials in field emission, display, biomedical, energy and sensor technologies. Detailed studies on the nanostructures obtained were carried out using various microscopy and probe-based techniques for structural, morphological and chemical characterizations.

Keywords : Multisegmented nanowires, template-assisted electrodeposition, gold nanostructures

Effect Of Wetting Agents In Milling Process On CaCu₃Ti4O₁₂ Microstructures 
Mohd Fariz Ab Rahman, Julie Juliewatty Mohamed, Sabar D. Hutagalung
School of Materials and Mineral Resources Engineering,
Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia

Abstract

In this paper presented the effect of wetting agents in wet milling process on the formation of CaCu₃Ti₄O₁₂ (CCTO) electroceramics. The raw materials of CaCO₃, CuO, and TiO₂ were wet ball milled for 1 hour using different wetting agents which are deionized water and acetone. The milled powder was calcined at 900^oC for 12 hours in air. X-ray diffraction (XRD) analysis was done to identify the phase formation of CCTO. The free powder then was pressed into pellet shape at 200 MPa. The pellet was sintered at 1040^oC for 10 hours. Density of sintered pellet was measured by Archimedes. Meanwhile, the microstructure was observed by scanning electron microscopy (SEM). All calcined samples show the formation of CCTO phase with trace of unreacted raw materials phases. Completed forrmation of CCTO single phase was obtained for all sintered pellets. Samples milled in deionized water produce finer grains (1-5 microns), meanwhile abnormal grain growth (50-100 microns) was observed for the sample milled in acetone. Morever, sample milled in acetone better is denser and less porous compared to the sample milled in deionized water. The results indicate that wetting agent is play an important role on the formation of CCTO electroceramics.

Keywords : CaCu₃Ti₄O₁₂, wet milling, wettting agents, phase structure, microstructures

EFFECT OF SINTERING TEMPERATURE ON PHYSICAL AND ELECTROMAGNETIC PROPERTIES OF MgFe₂O₄ FERRITES VIA SOLUTION COMBUSTION METHOD
Nilar Lwin1, Ahmad Fauzi M.N1*, Srimala sreekantan1, Radzali Othman1, Aye Aye Thant2

1School of Materials and Mineral Resources Engineering, Universiti Sains Malaysi
14300, Nibong Tebal, Pulau Pinang, Malaysia
2Physics Department, University of Yangon, Kamayut, Yangon, Myanmar

Abstract

Pollycrystalline MgFe₂O₄ ferrite was prepared by solution combustion method using metal nitrates and citric acid. Enhancement of the density of the samples has been observed with the increasing in sintering temperature and has great influence on the electromagnetic properties of MgFe₂O₄. The XRD analysis of the as-synthesized powder confirms the formation of the single phase MgFe_{2O4 spinel structure. Decrease in resistivity with increase in sintering temperature confirms the semiconducting behavior of the prepared ferrites. It was found that magnetic properties can be tuned by different sintering conditions. Also the increased value of dielectric constant (ε′)has been observed with the increase in sintering temperature. There was no maximum dielectric loss within the measured frequency range until 1 GHz due to excellent compositional control in this method.}

Keywords : ferrite/ resistivity/ dielectric loss/ dielectric constant/ magnetic

Effect of Firing Temperature on Microstructure and Optical Properties of Strontium Aluminate Phosphor
Ahmad Fauzi Mohd Noor
School of Materials and Mineral Resources Engineering, University sains Malaysia
Engineering Campus, 14300 Nibong Tebal
Pulau Pinang

Abstract

A series of SrAl2O4: Eu2+, Dy3 crystals with different firing temperature from 1100 °C to 1300 °C were synthesized by solid state method. The powders were calcined at these temperatures for 2 hrs at heating rate of 10oC/min in graphite crucible. The effect of temperature on luminescence property have been investigated. The samples were characterized by X-Ray Diffraction (XRD). The results reveal that the presence of crystalline monoclinic structure of SrAl2O4 and the intermediates phase formed were identified as Sr4Al14O25. TG / DTA, SEM and Photoluminescence spectra have been used to characterize the synthesized phosphor. After being irradiated with ultraviolet (UV) light, the phosphor powder fired at 1250°C had emitted long lasting green phosphorescence with an excitation peak at 325 nm and emission peak at 527 nm. Glow intensity of phosphor prepared at different synthesis temperatures were also observed and attributed to the presence of different phases and also on the diffusion of Eu2+ and Dy3+ in the matrices.

Keywords : photoluminescence, ceramics, temperature, emission spectra

Quantitative evaluation of cellular properties in culture through microscopic image processing
Shiplu Roy Chowdhury^1,2,3*, Masahiro Kino-oka², Masahito Taya³, Ruszymah Bt Hj Idrus^1,4
1Tissue Engineering Centre, UKM Medical Centre, Malaysia,
³Division of Chemical Engineering, Graduate School of Engineering Sci
⁴Department of Physiology, Faculty of Medicine, UKM, Malaysia

Abstract

The quantitative in vitro approaches are considered as valuable predictors of cellular properties in medicine and biological research. Microscopes incorporated with specialized software for acquisition and analysis of digital images makes possible the quantitative evaluation of cellular properties both invasively and non-invasively. In our study, quantitative evaluation through analysis of microscopic images was employed for optimizing in vitro culture process of myoblasts to achieve cells with desired quantity and quality for clinical uses. In which growth properties (lag time, attachment, growth rate etc.), migration rate, cytokinesis time of cell division, confluence degree was quantitatively evaluated through non-invasive process. Population balance between proliferative and non-proliferative cells was also evaluated quantitatively through immunostaining procedure (invasive process). These parameters and their correlation was used to design and optimize myoblast culture process, which facilitates the 8 times enhancement of final cell number. Similar approach was employed to establish the keratinocytes culture process for enhancing expansion. In conclusion, processing of microscopic images provides valuable tool to express the biological behaviors of cells in quantitative manner that helps to understand the correlation between different properties and optimize the culture process for achieving required quantity and quality of cells for clinical use.

Keywords : Image Analysis, Quantitative evaluation of cellular properties, Invasive and Non-invasive technique, Myoblasts and Keratinocytes,

BILAYERED TISSUE ENGINEERED SKIN TO TREAT SKIN LOST AFTER RADIOTHERAPY: HISTOLOGICAL AND ELECTRON MICROSCOPIC ANALYSIS
MB Fauzi¹, I Fuad³, WA Amirudin³, M Wahyudi³, BS Aminuddin^2,1 and BHI Ruszymah^1,4 
1Tissue Engineering Centre, UKM Medical Centre, Jalan Yaacob Latiff,
Bandar Tun Razak, 56000 Cheras, Kuala Lumpur,
²Ear, Nose & Throat Consultant Clinic, Ampang Puteri Specialist Hospital,
³Department of Radiotherapy and Oncology, UKM Medical Centre, Jalan Yaacob Latiff,
Bandar Tun Razak, 56000 Cheras, Kuala Lumpur.
⁴Department of Physiology, Medical Faculty UKM, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur.

Abstract

Radiation therapy to cancer patients can cause ulcer or skin loss and this will result in delayed wound healing. In this study, human skin cells have been used to produce bilayered tissue engineered skin substitute (BTESS) to treat skin lost after gamma irradiation. The effectiveness of BTESS was compared to monolayered tissue engineered skin substitute (MTESS). 30 kGy of gamma ray was irradiated to the hind leg of nude mice before creating the skin lesion. The BTESS was implanted to the wounded area and the wound area size was measured (mm2). Skin regeneration and morphological appearance were observed via Hematoxylin & Eosin staining (H&E) & Transmission Electron Microscopy (TEM) analysis. When the wound area that was treated with BTESS had completely healed, the MTESS still showed wound size of (0.11±0.05 mm2) and control (0.68±0.14 mm2). Grossly the gamma irradiated-wound area healed completely in 13 days. H & E analysis showed that BTESS had incorporated with the surrounding skin. TEM analysis showed tight-junction had developed in case of BTESS. Both micrograph analysis demonstrated the properties of better wound healing in BTESS. In conclusion, BTESS could be used to treat skin loss after radiation therapy.

Keywords : Tissue engineering, Bilayered tissue engineered skin substitute, Transmission Electron Microscopy, Histology

Immunocytochemical Analysis of Human Keratinocytes and Fibroblasts using Different Trypsinization Enzymes in Cells Culture: towards Clinical Application
 M Manira1, A K Khairul1, W T Seet1, A W Ahmad Irfan1, M H Ng1, K H Chua2,1, M Y Mohd. Heikal 2,1, B S Aminuddin 3,1, B H I Ruszymah1,2
1Tissue Engineering Centre, Universiti Kebangsaan Malaysia Medical Centre
3Ear Nose & Throat Consultant Clinic, Ampang Puteri Specialist Hospital, Selango

Abstract

Trypsin is an important reagent used to detach cells from culture vessels for further cells manipulation. Conventionally, animal-derived trypsin is used in the laboratories. However with the aim for clinical application, non-animal derived trypsin is preferred. The aim of this study was to compare the specific protein markers of keratinocytes and fibroblasts after exposure to animal-derived trypsin and recombinant trypsin. The skin biopsy was digested in 0.6%Collagenase Type I for 6 hours to isolate the fibroblast, followed by trypsinization of epidermal layer using animal-derived trypsin (TE)(0.05%) or recombinant trypsin (RT)(1x). The cells were cultured until passage 2 and protein expression of Cytokeratin10 (CK10), Cytokeratin14 (CK14), Collagen type I (Col I) and III (Col III) were quantitatively analyzed via immunocytochemical staining viewed under fluorescence microscope (Nikon, Tokyo). Results showed that both TE and RT positively expressed the specific gene of interest. Keratinocytes were stained positive by CK10 and CK14 antibodies for both TE and RT treated cells. Fibroblasts from both groups were also positively stained for Col I and Col III. This indicates the presence of basal cell protein for keratins and extracellular matrix for epithelial cells. In conclusion, recombinant trypsin can be used as an alternative for trypsin in clinical application.

Keywords : Keratinocytes, Fibroblasts, Animal-Derived Trypsin, Recombinant Trypsin, Cytokeratin, Collagen, Tissue Engineering

HUMAN BONE MARROW MESENCHYMAL STEM CELLS CAN BE DIFFERENTIATED TO CORNEAL EPITHELIAL LINEAGES PROVEN BY PRESENCE OF CK3 AND p63: AN IMMUNOCYTOCHEMICAL EVALUATION
Rohaina CM1 *, Then KY2, Ng MH1, Aminuddin BS3, 1, Ruszymah BHI1, 4
1Tissue Engineering Centre, Universiti Kebangsaan Malaysia Medical Centre
2Department of Ophthalmology, Faculty of Medicine, Universiti Kebangsaan Malays
3Ear, Nose & Throat Consultant Clinic, Ampang Puteri Specialist Hospital, Selang
4Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia

Abstract

Interest in developing tissue-engineered cornea has increased with the lacking of tissue donor. Bone marrow was recognized as a source of progenitor cells for epithelial cells which was important to treat limbal stem cells deficiency. The aim of this study was to differentiate human bone marrow MSCs to corneal epithelial lineages and to characterize the protein expression of differentiated bone marrow in vitro. Bone marrow was obtained from interlocking nail fixation procedure with patient’s written consent. Human bone marrow cells were isolated using Ficoll-Paque PLUS solution under gradient isolation procedures. Cells were expanded until Passage 2 and resuspended in F12: DMEM+10% serum and limbal medium consisted of F12: DMEM, hydrocortisone, insulin, tri-iodotyronine, adenine, cholera toxin and EGF for up to 10 days. The cells were subjected to immunocytochemical analysis to detect CK3 and p63 protein expression. Induced bone marrow cells showed approximately 70% positive stains for p63 marker and 50% positivity in CK3 marker while uninduced bone marrow cells demonstrated negative stains for both markers. Quantitative data can be acquired using confocal microscopy system (Nikon A1R) and image analysis software (NIS-Elements Viewer 3.20). Hence, we conclude that induced bone marrow cells by limbal medium have the potential to differentiate to corneal lineages.

Keywords : Bone marrow, cornea, limbal medium, immunocytochemical, tissue engineering

MICRO-CT ANALYSIS PROVES BONE REGENERATION FOLLOWING IMPLANTATION OF BETA-TCP/HA GRANULES SEEDED WITH BONE MARROW STEM CELLS
 S Sharen Aini^1,2, R Masfueh³, B Badiah³, BS Shamsul¹, CK Low⁴, AJ Mohd Nazimi3, R Nordin³ , Y Norziha³, AS Shariffah Shuriana³, BHI Ruszymah^1,2, CH Siar¹Tissue Engineering Centre, UKM Medical Centre Malaysia
³Faculty of Dentistry, UKM Malaysia,
⁴Laboratory Animal Resource Unit, UKM Malaysia
⁵Dept of Oral Pathology, Oral Medicine and Periodontology, UM Malaysia.

Abstract

Alveolar ridge defect can be caused by lost of teeth, bone resorption or periodontal diseases. Current treatment uses autologous bone graft from the iliac crest to raise the alveolar ridge. However this is limited by donor graft availability and possible donor site morbidity. We aim to use Beta-TCP/HA granules seeded with autologous BMSCs to restore alveolar ridge defects in big animal models i.e. Macaca fascicularis. BMSCs aspirated from the femurs were cultured in MEM-alpha medium supplemented with 10% FBS + 5% autologous serum, 0.2mM acid ascorbic 2-phosphate, 10mM Beta-glycerolphosphate and 10-8 molar dexamethasone. Alveolar ridge defect was created on the same animal by molar and premolar teeth extraction followed by removing the portion of alveolar bone. Approximately 3×107cells mixed with autologous plasma and seeded into Beta-TCP/HA granule were then implanted into the defect area. After 3 months, animals were sacrificed and sample from the defect area harvested. Micro CT analysis confirms the presence of residual Beta-TCP/HA granules 3 months post-implantation along with newly regenerated bone. In addition, the hematoxylin and eosin staining revealed two integrated but distinct bone layers showing the integration of engineered tissue with native tissue. In conclusion, cell seeded-Beta-TCP/HA can be used to treat alveolar ridge defect.

Keywords : Bone, Tissue Engineering, Alveolar ridge, Bone Marrow Stem Cells, Beta-TCP/HA granules

Evaluation of Post-Injected Cells in Sheep Osteoarthritic Models using Microscopy
C C Ude^1,2*, BS Shamsul², MH Ng², HC Chen³, YN Hamdan⁴, BS Aminuddin^5,2 BHI Ruszymah^2,1
1 Department of Physiology, Medical Faculty Universiti Kebangsaan Malaysia, Mal
² Tissue Engineering Centre, Universiti Kebangsaan Malaysia Medical Centre, Mal
³ Faculty of Veterinary Medicine, Universiti Putra Malaysia, Malaysia
⁴ Dept. of Orthopedic & Traumatology Universiti Kebangsaan Malaysia Medical Cen
⁵ ENT Consultant Clinic, Ampang Putra Specialist Hospital, Malaysia

Abstract

The field of cellular transplantation and therapy need methodologies to longitudinally evaluate transplanted cells in vivo. Confocal microscope is an excellent tool to track cells in 3D tissues. Chondrogenically-induced PKH26 labeled bone marrow stem cells (BMSC) and adipose stem cells (ADSC) were tracked 3 months post-implantation. OA was induced in sheep by complete resection of the anterior cruciate ligament and the medial meniscus in one knee following a 3-week exercise regime. Stem cells from the experimental sheep were labeled with PKH26 before their induction toward chondrogenic lineage. Test sheep received 2x107 autologous BMSCs or ADSCs injected as 5mls cell suspension, while the controls received 5mls basal medium. Sheep were euthanized and samples harvested. Grossly, treated knees showed de novo cartilages. Under light microscopy, H&E and Safranin O staining revealed loosely packed matrices in the regenerated cartilages. Under confocal microscopy, Collagen II and SOX9 specific protein markers for cartilage were detected. The PKH26-labelled cells were located on the regenerated cartilage and their spatial organization can be appreciated. This technique confirmed that autologous BMSCs and ADSCs are suitable cell sources which played an active role in cartilage regeneration. With the aid of confocal microscopy (NIKON –A1R), successful cell tracking was made possible.

Keywords : Tissue Engineering, Bone marrow stem cells, Adipose stem cells, Cell tracking, Microscopy

Preparation, characterization and photocatalytic activity of CdS nanorod by hydrothermal
Low Jing Xiang , Teressa Ludu Nathan
Multimedia University, jalan multimedia
cyberjaya,Malaysia
63000

Abstract

The production of renewable hydrogen through water-splitting using photocatalyst has received much attention because of increasing demand in the energy market. Cadmium sulfide with a novel rod-like architecture was successfully fabricated by a controlled hydrothermal reaction. The synthesis of visible-light-driven CdS nanorod-type photocatalyst by a simple hydrothermal method is reported. A special emphasis on using CdS-nanorod as the photocatalyst which have a large surface area and theoretically will improve the rate of hydrogen production. Other than that, with comparative low bandgap energy, CdS is suitable to use as the visible light range photocatalyst. This work will show a possibility for the change of the crystal structure of CdS to the photoactive of the photocatalyst materials. Different sacrificial agent is used to scavenge the electron hole on the surface of photocatalys. Effects of different sacrificial agents onto the photocatalysis process of CdS are compared respectively. This work highlights the potential application of CdS based materials in the field of hydrogen production.

Keywords : CdS nanorod photocatalyst water-splitting

Silica shell coating of faceted magnetite core
Theng Yee Chong
Jalan Multimedia, 63000 Cyberjaya, Malaysia

Abstract

Magnetite (Fe3O4), as a magnetic material, possesses novel properties at nano regime, one of them being superparamagnetism, which is of interest especially in the biomedical field. Surface treatment is required to change the hydrophobic magnetite into hydrophilic for suitable biomedical applications. Here, the surface modification of silica shell onto magnetite nanoparticle is reported. The final shaping of the magnetite-silica core-shell structure is investigated by performing the shell coating onto three different shapes of magnetite, namely spherical, cubical and rhombicubochedral. Polyol thermal decomposition is adapted for synthesis of magnetite, whereas the sol-gel Stober method is used for silica shell formation. It is found out that the faceted core with different surface energy in each plane influences the thin shell coating of silica, whereas when the thickness of shell is increased, the core shape effect is minimised. It is believed that besides the strong electron affinity interaction between core and shell, the surface energy of the core is also an affecting influence in the core-shell formation.

Keywords :

The growth of thick aligned carbon nanotubes using floating catalyst method
M.K. Lai, N.M. Mohamed
Center of Innovative Nanostructures and Nanodevices (COINN), Universiti Teknolog

Abstract

Floating catalyst method of growing carbon nanotubes (CNTs) involves the decomposition of ferrocene which acts as the source for catalyst. CNT was synthesized in a dual furnace using two types of substrate preparation, with alumina buffer layer and without. Ferrocene is placed inside zone 1 while the substrates are located at zone 2. The temperature in zone 1 is initially kept at room temperature while zone 2 is heated up at 10^oC/min in the presence of Ar until 850^oC at which CNTs growth took place. Prior to temperature in zone 2 reaching 850^oC, zone 1 is heated up in order for zone 1 and zone 2 reaching 150^oC and 850^oC, respectively, at the same time. At the reaction temperature, a mixture of ethylene and Ar is purged into the furnace at a ratio of 1:4 for 1 h. For samples with buffer layer, SEM image (Figure 1) reveals the thickness of the film to about 500 µm. However, only bulk CNTs is seen in those samples without buffer layer. From these observations, we found that the growth rate is much higher compared to the fixed catalyst method previously used and alumina buffer layer is required for the growth of aligned carbon nanotubes, similar to that in fixed catalyst method.

Keywords : floating catalyst CVD, aligned carbon nanotubes

Mild synthesis and Characterization of Ultra-small Cadmium Selenide Quantum Dots in Octadecene Solution
Charles Ahamefula Ubani1,
Mohamad Yusof Sulaiman, Z.ahai Ibarahim, Noor Baa'ya Ibrahim, Molhd Yusof Othm
Office of the Postgraduate Box 69, Department of Physics, Faculty of Science and
University Kebangsaan Malaysia, 43600 Bangi Selagor D.E, Selangor Malaysia

Abstract

Semiconductor quantum dot (QD) exhibit diverse opto-electrical properties for multitask applications which can be stimulated by spatial control distribution of their chemical composition. These unique properties facilitated the synthesis of ultra-small non-injection one-pot cadmium selenide (CdSe) QDs in octadecene (OTD) solution at mild temperature in quest for innovation-driven cost reductions of photovoltaic material. The synthesis that lasted for 2hrs started by heating 10ml of OTD to 35^oC followed by the addition of 13gm of cadmium oxide (CdO), 0.4ml trioctlyphosphine (TOPO), 0.6ml of oleic acid (OA) and 5mg of selenium (Se) powder. The heating was extended to 95oC on adding the mixtures. The optical properties of the colloidal CdSe QDs generated upon reaction were characterized using absorption spectroscopy (UV-vis) and photoluminescence spectroscopy (PL). Atomic force microscopy (AFM) and scanning electron microscopy (SEM) revealed the surface orientation of the CdSe QD particles. The morphology and microstructure image of the CdSe QD studied using transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) revealed the cubic structure of the sample. Although the operation was safe, the low-cost reproducible mild synthesized high-quality CdSe QDs was stable for about five months.

Keywords : CdSe QDs, Nanocrystals, Photoluminescence, Mild synthesis.

STEM/NBD for crystal orientation mapping: improved quality with precession electron diffraction and energy filtering
Giuseppe Pavia ¹, Gerd Benner ¹, Harald Niebel ¹, Edgar Rauch ^2
1 Carl Zeiss NTS, Carl Zeiss Strasse 56, 73447 Oberkochen, Germany
² SIMAP Laboratory, 101 rue de la Physique, 38402 Saint Martin d´Hèr

Abstract

Crystal analysis techniques like X-Ray Diffraction (XRD) and Electron Backscatter Diffraction (EBSD) are reaching their spatial resolution limit. Extending those methods to Transmission Electron Microscopy (TEM) is a way to improve spatial resolution. We will focus on crystal orientation mapping. Nowadays, Automatic Crystal Orientation Mapping (ACOM) and Automatic Crystal Orientation and Phase Mapping (ASTAR) experience a large worldwide dissemination. Both require the TEM Nano Beam Diffraction (NBD) functionality. We show here results obtained in STEM/NBD mode, which allows both the diffraction patterns (DP) and sample images to be acquired under the same microscope configuration. STEM/NBD is evaluated by considering the 180° orientation ambiguity that frequently occurs for zone axis DPs. It is confirmed that the combination of STEM/NBD with Precession Electron Diffraction (PED) dramatically reduces the extent of this ambiguity. We also demonstrate for the first time that Zero Loss Filtering (ZLF) has a similar beneficial effect on the indexing quality. The large angular acceptance of a corrected in-column Omega filter allows also combining PED and ZLF. The beneficial effect of PED is related to the higher number of reflection excited when the beam is precessed. ZLF improves indexing by significantly increasing the signal over background in the DP, allowing unambiguous identification of the diffraction spots.

Keywords : STEM, Nano Beam diffraction, Precession Electron Diffraction, Energy Filtering

MORPHOLOGICAL AND MECHANICAL PROPERTIES OF NOVEL MEMBRANE OF CHITOSAN/HALLOYSITE NANOCOMPOSITES
Pooria Pasbakhsh, Pooria Pasbakhsh, Rangika De Silva, Goh Kheng Lim, Chai SP, San Hein

Monash University, School of Engineering, 46150, Bandar Sunway, Selangor, Malays

Abstract

The current study has focused on the fabrication of chitosan/halloysite nanotubes (HNTs) nanocomposite membranes using a simple solution casting method, as well as characterization of their morphological and mechanical properties. Chitosan was reinforced by 2w%, 5w%, 10w% and 15w% HNT concentration in order to improve its mechanical properties. Young’s modulus and tensile stress of the nanocomposites at 5w% of HNTs significantly improved by 21% and 34%, respectively, compared to unreinforced chitosan membranes. Scanning electron microscopy (SEM) of membranes at 2% and 5w% of HNTs showed low amounts of pulled-out nanotubes which confirmed by the presence of more embedded nanotubes inside the chitosan matrix as well as less amounts of microvoids at the fractured surface of chitosan/HNT nanocomposites. SEM also shows HNT-rich areas and chitosan-rich areas in the fracture surfaces, and this phase difference could lead to crack propagation due to the high stress concentration. FTIR shows possible interaction of external surface siloxane groups of the HNTs with the matrix and also shows the aggregation of HNTs at higher loadings.

Keywords : Halloysite nanotubes, Scanning electron microscopy, Chitosan, Membrane.

Utilization of starch in supporting the growth of degrading microorganism on Natural Rubber Latex films surface.
M.M Afiq and A.R Azura
SMMRE, Engineering Campus, Universiti Sains Malaysia, 14300, Nibong Tebal
Penang

Abstract

NRL were compounded with 0, 10 and 25 phr of sago starch loading and were buried in compost soil for 4 weeks. The biodegradation assessments were made by taking films Water Vapor Transmission (WVT) and its mass loss. Scanning Electron Microscopy was used to identify and monitor the properties of rubber degrading organism colony. Results indicate that incorporation of sago starch increased the formation and the rates of propagation for microorganism colonies on NRL films as the weeks of biodegradation test elapses. Thus, in this study, the effect of sago starch loading in supporting the growth of rubber degrading organism on NRL films was investigated.

Keywords : Natural Rubber Latex (NRL), Starch, Microorganism, growth, Scanning Electron Microscopy (SEM)

Effect of Sago Starch on the formation of bacterial degrading organism on Natural Rubber Latex (NRL) films surfaces
M.M Afiq and A.R Azura
SMMRE, Engineering Campus, Universiti Sains Malaysia, 14300, Nibong Tebal
Penang

Abstract

NRL were compounded with 0, 10 and 25 phr of sago starch loading and were buried in compost soil for 4 weeks. The biodegradation assessments were made by taking films water vapor transmission and mass loss properties. The formation and propagation of hollow region manifesting the consumption of NRL films by microorganism were taken by Scanning Electron Microscopy (SEM) as well as the Identification of microorganisms’ types. Results indicate that incorporation of sago starch increased the biodegradability of NRL films. The SEM images confirmed the formation and types of microorganism that resides in NRL films. In this study, the effect of sago starch loading in NRL compounds biodegradability properties were investigated as well as the types and significance of microbial involved.

Keywords : Natural Rubber Latex, Sago Starch, Biodegradation, Microorganism, Scanning Electron Microscopy

Characterization Of A Laotian Clay And Its Properties Upon Firing
K. K. Sengphet^a, K. Pasomsouk^b, Tsutomu Sato^c, M.N. Ahmad Fauzi^a, O. Radzali<sup>a

a</sup>School of Materials and Mineral Resources Engineering, Universiti Sa
^bDepartments of Mechanical Engineering, National University of Laos (
^ccGraduate school of Engineering, Hokkaido University, kita13 Nishi8,

Abstract

This study focused on the mineralogical, chemical, thermal and physical characterization of a yellow clay from Laos and of the potential of the clays to be manufactured into traditional ceramic products. The raw clay was investigated in order optimize the fabrication process, where the clay samples were fired at different temperatures from 1000 ^oC to 1250 ^oC. The properties of the fired samples were determined and these included bulk density, apparent porosity, water adsorption, shrinkage and flexural strength. The apparent porosity and flexural strength of the samples showed that porosity decreased from 34.42 ±0.35 to 10.26 ±3.39 % with increasing sintering temperatures, whilst the flexural strength increased from 24.25 ±0.30 to 114.86 ±3.11 MPa (at 1000-1150^oC) but decreased significantly to 47.38 ±0.21 MPa upon firing at 1250^oC. The other properties were also measured and these included bulk density, water absorption, shrinkage and morphological changers.

Keywords : Clay minerals, Morphology, Sintering temperature, Laotian clay, Ceramic bodies

THE EFFECT OF AGEING TEMPERATURE ON AGEING RESPONSE OF DILUTE ALLOY Al-0.21wt%Mg-0.62wt%Si
 C.N.Aiza Jaafar, I.Zainol and Mohd Harun
School of Materials and Mineral Resources Engineering,
Engineering Campus, University Sains Malaysia,
14300 Nibong Tebal, Seberang Perai Selatan, Malaysia

Abstract

This work is aimed to obtain the effect of ageing temperature on ageing response of alloy Al-0.21wt%Mg-0.62wt%Si. The effects of room temperature (natural ageing) and elevated temperature (artificial ageing) were studied on this alloy. The ageing response of alloys during natural and artificial was monitored by Vickers hardness test. Tensile test were performed on this alloy at room temperature and 185^oC and the tensile properties such as yield stress (YS), ultimate tensile strength (UTS) and elongation are confirmed. Microstructures of artificially aged alloys were characterized using transmission electron microscopy (TEM). The work revealed that the peak hardness values decreases with the increasing artificial ageing temperature. The highest tensile strength were found in the alloy that artificially aged at 185^oC compared to the alloy that aged at room temperature whereas the elongation results revealed in contrast. Results also indicate that the precipitates formed during peak ageing at 185 and 300^oC were needle-shaped precipitates. Longer needle-shaped precipitates with lower number density were found in the alloy that aged at higher ageing temperature than that of lower ageing temperature.

Keywords : Al-Mg-Si alloy, artificial ageing, hardness, tensile, TEM

Physical and Electrochemical Properties of Activated Carbon Pellet from Pre-Carbonized Fibers of Oil Palm Empty Fruit Bunches by Carbonization Temperature and CO2Activation
Mansor M. Saman¹ , Mohamad Deraman^2
1Advanced Material Research Centre, SIRIM Berhad, Kulim Hi-Tech Park
²School of Applied Physic, Faculty of Science and Technology, Univers

Abstract

The physical and electrochemical properties of the activated carbon pellet electrodes have been investigated. Activated carbon pellets were prepared from single step carbonization process of pre-carbonized oil palm empty fruit bunches at difference temperature of 500 to 900 ^oC prior to CO₂ activation process at temperature of 900 ^oC for 2 and 4 hours. The BET characterization on the sample found that the surface area of the carbon pellet varied with carbonization temperature.. The optimum value was as high as 554.82 m2 g-1. Furthermore during CO₂ activation process for 4 hours, porosity increased tremendously to 920 m2 g-1. SEM micrographs show that CO₂ activation process at temperature of 900 ^oC for 4 hours more porous compare to 2 hours activation time. Typical optimum value was shown by the sample carbonization at 500 ^oC and CO₂ activation at 900^oC with the specific capacitance was as high as 131 F g-1 (scan rate 1 mV s-1).

Keywords : Oil Palm Empty Fruit Bunches, activated carbon, surface area, specific capacitance, morphology

THE INVESTIGATION OF DIOSCOREA HISPIDA IN REDANG ISLAND
S. A. Hashim, Nashriyah M., Khairil M., H. Norhaslinda, , N. Norhayati, Nor Zaimah Ab. Rashid, and Noratiqah
Faculty of Agriculture and Biotechnology, Universiti Sultan Zainal Abidin, City

Abstract

Dioscorea hispida which is locally known as Ubi Gadong in Malaysia. Dioscorea hispida was important in agricultural crops in tropical regions, grown for their large tubers,.have a toxic when fresh, but it can be detoxified and eaten. In this study, a scientific expedition was done on 16th to 21st of May 2011 with a colloboration between Univesiti Sultan Zainal Abidin and Terengganu Forestry Department to investigate Dioscorea hispida in Redang island, Terengganu, Malaysia. A total of three places have been identified and tracked to evaluate the species of dioscorea hispida in Redang Island. The morphology of Dioscorea hispida was captured using the Scanning Electrons Microscopy (SEM) and its show that all of dioscorea hispida in three places in Redang Island have a same genus. Then, the geographical information of Dioscorea hispida in Redang Island was plotted using the Quickbird satellite images to map the distribution of Dioscorea hispida species in Redang Island. A study was shown, Redang Island have been suitable as a place for cultivation of Dioscorea hispida.

Keywords : Dioscorea hispida, Scanning Electron Microscope, SEM, Quickbird

Biomechanical and Biosafety of Injection Moulded Implant Materials
M.A.Omar^a, A.H.Zulkifly^b, N.Abdullah^a, N.M.Zainon^a, N. Roslani<sup>a

a</sup>AMREC, Lot 34, Jalan Hi Tech 2/3, Kulim, Hi Tech Park, 09000 Kulim,
^bDepartment of Orthopaedic, Kulliyah of Medicine, International Islam

Abstract

The biomechanical and biocompatibility evaluation of 316L stainless steel fracture fixation plates produced through metal injection moulding technique were performed. These studies are part of tests that is very important to determine the biomechanical, biosafety and biocompatibility and toxicity of the Metal injection metal implant. These are very important to determine the safety of the implant that are going to be implanted in human. Since Metal Injection Moulding (MIM) techniques is a new methods to produce an orthopaedics implants it is mandatory to have a biosafety profile for the material.

Keywords :

STUDIES ON PHYSICAL PROPERTIES AND FRACTOGRAPHY OF ELECTRON BEAM IRRADIATED ETHYLENE VINYL ACETATE/WASTE TYRE DUST BLEND IN THE PRESENCE OF polyethylene graft of maleic anhydride (PEgMAH)
Syuhada¹, C.T. Ratnam², and S. H. Ahmad¹, and Nurul Athirah^3
1School of Applied Physics, Faculty of Science and Technology,
²Radiation Processing Technology Division, Malaysian Nuclear Agency
(Nuclear Malaysia), Bangi, 43000 Kajang, Malaysia
³School of Materials and Mineral Resources, USM Engineering Campus

Abstract

The effect of irradiation on the 80/20 EVA/WTD blend was studied in the presence of 0 to 5% of polyethylene graft of maleic anhydride (PEgMAH). The blend was irradiated by using a 3.0 MeV electron beam machine at doses ranging from 20 to 200 kGy in air and room temperature. The gel fraction, tensile strength(Ts), elongation at break(Eb) and Modulus at 100% elongation (M100) were measured. Electron beam irradiation of the EVA/WTD blend were found to cause crosslinking which in effect caused an enhancement in modulus and gel fraction together with a concomitant decline in ultimate elongation. The tensile strength of the blend reached a maximum at 150 kGy in the presence of 1 % PEgMAH followed by a decrease at higher doses and higher PEgMAH. The scanning electron micrographs of the fracture surfaces of the irradiated blends show evidence consistent with the above contention.

Keywords : Ethylene Vinyl Acetate (EVA), Waste Tire dust (WTD), irradiation effect, crosslinking

Effect of Different Types of Starch on Biodegradable Natural Rubber Latex Films
Y. S. Rohana, C.C. Tan and A.R. Azura
School of Materials and Mineral Resources Engineering
Universiti Sains Malaysia
Engineering Campus
14300 Nibong Tebal
Penang, Malaysia.

Abstract

The main focus of this research is to investigate the biodegradation behavior of natural rubber latex by incorporating different types of natural fillers which are sago, tapioca and rice starches. The starch loading of 10 phr were added to accelerate the biodegradation process of natural rubber latex films. Ball mills were employed to prepare the dispersion of fillers. The dispersed fillers are added into the latex compound prior to pre-vulcanization process at 70^oC. The dipped films are cured in oven at 100^oC for 20 minutes and cooled at room temperature for 24 hours before stripping. The films were buried in soil for four weeks to study the biodegradation activities. The morphological studies on the dispersion and biodegradability of starches in natural rubber latex films were analyzed by scanning electron microscopy (SEM) and optical microscopy. The results indicated that the rice starch was not compatible with natural rubber latex. The weak rubber – filler interactions of natural rubber latex with sago and tapioca starches were observed via SEM. From optical microscopy observation, the microorganisms were more attracted to tapioca starch than sago starch filled natural rubber latex films thus increased the biodegradation activities.

Keywords : Natural rubber latex, natural fillers, sago starch, tapioca starch, rice starch, biodegradation.

Morphological Studies on Mechanical and Chemical Modified Starch on Natural Rubber Latex Films
Y. S. Rohana, C.C. Tan and A.R. Azura
School of Materials and Mineral Resources Engineering
Universiti Sains Malaysia
Engineering Campus
14300 Nibong Tebal
Penang, Malaysia.

Abstract

Two different methods were carried out to improve the dispersion of starch in natural rubber latex. The methods included mechanical smashing using ball mills and chemically modified starch with polybutylacrylate (PBA) grafted chains. The dispersed fillers then added into the latex compound prior to pre-vulcanization process at 70^oC. The dipped films are cured in oven at 100^oC for 20 minutes and cooled at room temperature for 24 hours before stripping. The morphological observation via scanning electron microscopy (SEM) showed that the chemically modified starch showed better dispersion in natural rubber latex films compared with the starch prepared by mechanical smashing.

Keywords : Natural rubber latex films, starch, modified starch, polybutylacrylate, ball mills.

Effect of Sintering Temperature on Properties of 17-4PH Stainless Steel Alloy
M.Z.Nurazilah, A.Noorsyakirah, R.Norazlan, M.Bakar and O.Mohd Afian
AMREC SIRIM Berhad,
Kulim Hi-Tech Park,
09000 Kulim,
Kedah.

Abstract

Faced with global competitive pressures, a key for continued growth for the Metal Injection Moulding (MIM) lies in the ability to improve on the performance characteristics and cost effectiveness of materials and processing. In current study, the 17-4 PH stainless steel powder with the median particle size of 17.5µm has been chosen as a model materials mixed with paraffin wax (PW), polyethylene (PE), and stearic acid (SA) as a binder system. Five sintering temperatures were chosen which are 1300^oC, 1320^oC, 1340^oC, 1360^oC, and 1380^oC for sintering study. The density, hardness and tensile strength of the sintered specimen were measured using the standard procedure. Microstructure of the alloy was examined for correlating with the mechanical and physical properties.

Keywords : Metal Injection Moulding(MIM), 17-4PH, sintering temperature, tensile and microstructure

Rare-earth doped-Bismuth titanate and characterization for wireless dielectric antenna applications
Umar Al-Amani Azlan, Srimala Sreekantan, Ahmad Fauzi Mohd Noor, Khairunisak Abd. Razak
Pusat Pengajian Kejuruteraan Bahan & Sumber Mineral, Kampus Kejuruteraan,
Universiti Sains Malaysia, Nibong Tebal, 14300, Pulau Pinang, Malaysia.

Abstract

The phase formation, dielectric properties (dielectric constant, år and dielectric loss, tan ä) and microstructures of the Bi₄-xRExTi₃O₁₂ (RE: La₃⁺, Nd₃⁺, and Sm₃⁺ whereby x=0, 0.5 and 1) ceramics have been investigated. The presence of single phase bismuth-layered structure was confirmed by X-ray diffraction, XRD (Bruker Advance D8). Meanwhile, the microstructures of ceramics were observed by field emission scanning electron microscopy, FESEM (Zeiss Supra 35VP). The dielectric properties of ceramics were measured using the RF Impedance/Material Analyzer 4291B Hewlett Packard machine over a frequency range from 1 MHz to 1 GHz. In this study, the phase formation, dielectric properties and microstructures of corresponding ceramics can be effectively controlled by varying the rare-earth elements and the x value. It is proposed as a suitable candidate ceramic for wireless dielectric antenna applications.

Keywords : rare-earth, bismuth titanate, dielectric constant, dielectric loss, microstructure

A Study of Cobalt-Chromium-Molybdenum (Co-Cr-Mo) Metallic Prosthesis through Innovative Metal Injection Molding (MIM) For Orthopedic Applications
NoorsyakirahAbdulah, MohdAfianOmar, ShamsulBahrinJamaluddin^*, NurazilahMohdZainon, NorazlanRoslani, Abdullah AzzamAzenan, Bakar Meh, MohdNizamAbdJalil and Ahmad Zahid Omar

AMREC, SIRIM Berhad, Lot 34, jalan Hi Tech 2/3, Kulim Hi tech Park 09000 Kulim,
^*School of Materials Engineering,KompleksPusatPengajianUniMap (Taman

Abstract

Metal injection molding of 22μm Co-Cr-Mo powder was investigated. The binder system used consists of a major fraction of paraffin wax (PW), polyethylene and a minor fraction of stearic acid with a powder loading of 65 vol. %. The rheological behavior of feedstock was determined using Capillary Rheometer. The feedstock then injected into tensile bar using Vertical Injection Machine. Results indicated that the viscosity of the feedstock decreased as the temperature increased. The feedstock has been successfully injection molded at a temperature of 210^oC. The mechanical properties comply with the international standard (ASTM F75).

Keywords : MIM, Co-Cr-Mo, mechanical properties, medical applications

Esophageal Surface Cells in Non-erosive Reflux Disease (NERD): Scanning Electron Microscopic Study
*Dr Yi Yi Myint, Dr Ye Tun, Dr. Nasser Muhammad Amjad, Nor Linda Rashid, Dr. Mohd Zailani Mat Hassan
*Department of Basic Medical Science, Kulliyyah of Medicine,
International Islamic University of Malaysia, JalanIstana, Bandar Indera Mahkota
25200 Kuantan, Pahang Darul Makmur, Malaysia.
Phone: 006-09-5716609 ext 2483Fax:09 5716770, E-mail: yym_iiu@hotmail.com

Abstract

Background: Dilated intercellular spaces (DIS) in prickle cell layers are considered as early signs of acid damage to the esophageal epithelium. In order to enter the mucosal intercellular spaces, acid and pepsin have to penetrate the intercellular adhesion sites of the most superficial epithelial cells. Objectives: The aim of this study is to explore cellular attachments in most superficial esophageal cells of non- erosive (NERD) patients. Material and methods: The study group included 8 (NERD) patients and 5 normal controls. Specimens were routinely processed for SEM. The nature of cellular attachment and intercellular spaces between superficial cells of esophageal mucosa were viewed by SEM. Statistical analysis: The association between DIS and categorical data was accessed by using Chi-Square test. p <0.05 were considered to be statistically significant. Results: We found out that cellular attachments in the superficial cells differ significantly among the normal controls and patients with NERD (p value 0.007). Conclusions: Our results showed that the superficial cellular attachment did not differ significantly among control and patients with NERD (p>0.05) SEM study on DIS in esophageal surface cells is not a useful diagnostic test for differentiating between normal and NERD patients.

Keywords : Non-erosive Reflux Disease (NERD), Dilatation Intercellular spaces (DIS), cellular attachment,scanning electron microscopy (SEM)

Confocal and Light Microscopy Evaluation Of Human Adipose Tissue Derived Stem Cells Differentiated To Smooth Muscle Cells For The Regeneration Of Urinary Bladder Wall
Salah,AS¹, Zulkifili MZ², Ho CCK², Ismail S¹,Ng MH², Ruszymah BHI ^3
1Department of Surgery
²Tissue Engineering Centre
³Department of Physiology
University Kebangsaan Malaysia Medical Center
Bander Tun Razak
Jalan Yaacob Latiff, Cheras 56000, Kuala Lumpur

Abstract

Confocal and conventional light microscopy represents important evaluation tools for cell morphology and phenotypic properties. Our objective is to assess using confocal and light microscopy as tools to confirm differentiation of adipose derived stem cells (ADSCs) into smooth muscle cells. In this study, adipose tissue samples were digested, and the isolated ADSCs were cultured and expanded in vitro. ADSCs differentiation was induced by exposure to smooth muscle inductive media (SMIM) consisting of MCDB I31 medium, 1% FBS, 100 U/ml heparin for 6 weeks. ADSCs in non-inductive media were used as controls. Light and confocal microscopes were used to characterize cell differentiation by morphological changes and protein expressions. Using light microscopy, distinct morphological changes were identified upon differentiation. Differentiated cells became elongated and spindle shaped, and towards the end of 6 weeks, sporadic cell aggregation appeared which is typical for smooth muscle cells culture. At protein expression level, confocal provided a precise and sensitive tool to detect cytoplasmic protein expressions. Alfa smooth muscle actin (ASMA), myocin heavy chain (MHC) and smoothelin were expressed after 6 weeks of differentiation. As a conclusion confocal and light microscope provides a suitable tool for smooth muscle differentiation detection.

Keywords : Tissue Engineering, light microscopy, confocal microscopy, cell morphology, protein expression

A MORPHOLOGICAL STUDY ON HIGH TEMPERATURE OXIDE GROWTH OF ALUMINIZED CARBON STEEL
Hishamuddin Hj. Husain, Abdul Razak Daud , Muhamad Daud and Zahid Abdullah
School of Applied Physics,
Faculty of Science and Technology
Universiti Kebangsaan Malaysia
43600 Bangi, Selangor D.E

Abstract

The growth of thin oxide layer of the aluminized carbon steel which was subjected to high temperature was investigated. Hot dip aluminizing of low carbon steel was carried out at 750 ºC dipping temperature in a molten pure aluminum for 5 minutes. Aluminized samples were heat treated at 600 ºC, 700 ºC, 800 ºC, and 900 ºC for 1 hour. The formation of the aluminum oxide layer was confirmed by X-ray Diffraction (XRD).Then, the morphology of the oxide surface was observed by means of Scanning Electron Microscope (SEM). The Atomic Force Microscope was used to analyse the surface properties. It showed that surface roughness of oxidized samples increased with the increase in temperature.

Keywords : Low carbon steel, hot dip aluminizing and aluminum oxide.

FRACTURE TOUGHNESS AND IMPACT PROPERTIES OF HOLLOW EPOXY PARTICLES AND SOLID EPOXY PARTICLES REINFORCED VINYL ESTER COMPOSITES
LOW LAY FOON, AZHAR BIN ABU BAKAR
SCHOOL OF MATERIALS AND MINERAL RESOURCES ENGINEERING
ENGINEERING CAMPUS, UNIVERSITI SAINS MALAYSIA
14300 NIBONG TEBAL,
PENANG, MALAYSIA

Abstract

Hollow epoxy particles (HEP) and solid epoxy particles (SEP) fillers were prepared using water-based emulsion method in this present study. The morphological structures of HEP and SEP fillers produced using different homogenizing speed, ranging from 1,000 rpm to 15,000 rpm, were observed under field emission scanning electron microscope (FESEM). It was found that HEP and SEP fillers with smaller particle size and larger surface area could be prepared under higher homogenizing speed. HEP and SEP fillers were then incorporated into the vinyl ester matrix to strengthen and to toughen the vinyl ester composites. It was also determined that HEP and SEP produced at higher homogenizing speed showed greater capability to enhance the impact strength and fracture toughness of the composites. As a comparison, it was determined that HEP-filled composite possessed higher fracture toughness and impact strength compared to that of SEP-filled composites. This is mainly due to the hollow structure of the HEP fillers which allowed the vinyl ester matrix to interlock into the pore regions of the HEP and eventually enhanced the matrix-filler interaction.

Keywords : hollow epoxy particles, solid epoxy particles, homogenizing speed, fracture toughness, impact strength

Distribution of organoclay in PP/NR blends and its effect on the blend properties
Jamaliah Sharif, Hasnul Nizam Osman, Natasha Isnin
Agensi Nuklear Malaysia
43000 Kajang

Abstract

The distribution of organoclay in polypropylene (PP)/natural rubber (NR) blends and its effect on blend properties were investigated. Different ratio of PP/NR blends were melt blended with organoclay using a Haake internal mixer at 180ºC and 60 rpm rotor speed. The characterization was done using TEM, SEM and tensile test. TEM results clearly show that clay aggregates only dispersed in natural rubber phase. SEM micrographs show that the incorporation of organoclay into PP/NR blends has change the morphology of the blends into a homogeneous phase. This has resulted in better impact strength and thermal stability of PP/NR blends

Keywords : Polypropylene, natural rubber, organoclay, SEM, TEM

Histomorphometric Analysis of Endothelial Cell In Skin Microvasculature Among Diabetic Foot Ulcer Patients
H. M. Radzuan, Yi Yi Myint, Ye Tun
Kulliyyah of Medicine
Jalan Istana, Bandar Indera Mahkota
25200 Kuantan
Pahang Darul Makmur

Abstract

Introduction
Changes affecting endothelial cells in microcirculation of diabetic foot patients are important in the development of foot ulceration and subsequent failure to heal existing ulcers.

Methods
We studied 30 patients (10 control individuals, 10 with neuropathic ulcer and 10 with neuroischaemic ulcer). The specimens were taken using skin punch biopsy and were routinely processed for light microscopy. The mean endothelial cell count (ECC) was performed by calculating all the endothelial cells of 3 selected arterioles in each slide of every patient. The mean endothelial cell thicknesses (ECT) of all endothelia were measured using the image analyzer.

Results
There was significant decrement in ECC among the diseased group as compared to the controls, F(2,27)=5.31, p=0.01. The ECT of the diseased group were significantly higher than the controls, F(2,27)=52.42, p<0.01. The Tukey post-hoc comparisons indicate that the ECC and ECT of neuropathic group (M=5.63, 95% CI [4.87, 6.40], M=6.20, 95% CI [5.51, 6.90]) and neuroischemic group (M=5.70, 95% CI [4.98, 6.42], M=6.77, 95% CI [6.41, 7.12]) were not significant as p>0.05.

Conclusion
The decrement of ECC and the increment of ECT among diabetic foot patients could be due to the alteration in the endothelial cell function and structure as the results of the metabolic disease.
Keywords : Diabetic foot, microcirculation, endothelial cell count, endothelial cell thickness, oxidative stress

Physical Characterization of CaSO₄:Dy Thermoluminescence (TL) Material
Nadira Kamarudin and Wan Saffiey Wan Abdullah
Malaysian Nuclear Agency
Bangi,
43000 Kajang,
Selangor.

Abstract

CaSO₄:Dy have been prepared with the varies of dopant concentration of 0.1 mol% to 0.5 mol% by wet precipitation technique. The resulting CaSO₄:Dy powder were characterized using Particle Size Analysizer (PSA) and founded the particle size of the powder are around 4-5 micro m with the 91-95% yield. The morphology of CaSO₄ and determination of dopant was characterized using Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and Electron Dispersive X-ray (EDX).

Keywords : Thermoluminescence Detector Material, Electron Microscopy, Particle Size Analysis

Synthesis of ZnO film on Si (100) via chemical solution route
Muhammad Azmi Abdul Hamid, Maria Abu Bakar , Azman Jalar Roslinda Shamsudin
School of Applied Physics, Faculty of Science and Technology,
Bangi, UKM

Abstract

In this paper, flower-like zinc oxide (ZnO) on Si wafer (100) were prepared using aqueous chemical growth route. The morphology and optical observed were found to be influence by the reaction time. Field Emission Scanning Electron Microscopy (FESEM) revealed a branching out hexagonal rods growth on the substrates . XRD results shows that the intensity for (100), (002) and (101) increased with the increasing of reaction time. The ZnO film resistivity measured shows a decreased from 0.81 Ù cm for 1.5 h to 0.44 Ù cm when the reaction time increased to 3 h. This result indicates that the reaction time have some influence on morphology and resistivity of grown ZnO films

Keywords : ZnO, Si

NANOSTRUCTURED SOL-GEL COATINGS FOR CORROSION RESISTANCE
Poovarasi Balan*, Chan Eng Seng
Jalan Lagoon Selatan, 46150 Bandar Sunway,
Selangor Darul Ehsan, Malaysia

Abstract

Chromate pre-treatments on metals prior to coating impose heavy cost and environmental issues. For the past few decades, organosilane pre-treatments are seen as an environmental friendly alternative in replacing chromate pre-treatments. However, organosilane pre-treatments can only offer short-term corrosion protection unlike chromates. It has been demonstrated that addition of nanoparticles or corrosion inhibitors can provide extended corrosion protection to metals. In the present study, synergistic effect of adding both nanoparticle and corrosion inhibitors has been investigated. Pre-treatments containing silica nanoparticles, with and without activation of Lanthanum inhibitors impregnated within the hybrid sol-gel matrix were investigated. The hybrid sol-gel films have been synthesized from tetraethylorthosilicate (TEOS) and 3-glycidoxypropyltrimethoxysilane (GPTMS). Electrochemical Impedance Spectroscopy (EIS) measurements revealed highest improvements in samples containing both SiO2 and La inhibitors as compared to samples containing either one of them. The EIS results were fitted with equivalent electrical model to provide quantitative information on evolution of corrosion properties for different pre-treatments. The EIS results were supported by scanning electron microscopy measurements.

Keywords : Nanostructured coating, corrosion, low carbon steel, lanthanum, EIS, SEM

Vertically Aligned ZnO Nanorods Deposited on Silicon Substrate by Chemical Bath Deposition Route
Leng Pooi Li, Sabar D. Hutagalung
School of Materials and Mineral Resources Engineering
Universiti Sains Malaysia
14300 Nibong Tebal
Penang, Malaysia

Abstract

Zinc oxide (ZnO) nanorods were grown on silicon substrate by chemical bath deposition route in an aqueous solution that contained zinc nitrate hexahydrate (Zn(CH₃COO)₂.₂H₂O) and hexamethylenetetramine (C₆H₁₂N₄,HMT). In this work, the growth temperature was varied at 25, 60, 90 and 100^oC. It was found that vertically aligned ZnO nanorods can be grown at 60^oC for 1h, beyond this temperature obtained flower-like structures.

Keywords : ZnO, nanorod, chemical bath deposition, growth temperature

Enhanced Photoelectrochemical Response using TiO₂ Nanotubes by adding Ethylene Glycol as Organic Additive
Lai Chin Wei and Srimala Sreekantan
School of Materials and Mineral Resources Engineering,
Universiti Sains Malaysia Engineering Campus,
14300 Nibong Tebal, Seberang Perai Selatan,
Pulau Pinang, Malaysia.

Abstract

Well aligned and smooth TiO2 nanotubes have been demonstrated as a stable and promising material for generating hydrogen efficiently. However, the colossal problem in using TiO₂nanotubes as a photoanode is charge carrier (e- and h+) recombination loss during photoelectrochemical activity. In the present paper, the use of ethylene glycol was found to be a potential organic additive to add into the 1M KOH to reduce the charge carrier losses and improve the photoelectrochemical response of TiO₂ nanotubes. The addition of 1 vol% of ethylene glycol into 1M KOH electrolyte produced a photocurrent density of 1.0 mA/cm2 with photoconversion efficiency of 2.1%, which approximately 2 times improvement compared to pure 1M KOH electrolyte. The reason attribute to the higher charge carriers density and reduction of recombination losses.

Keywords : TiO2 nanotubes, ethylene glycol, photoelectrochemical

Processing, Characterization and Potential Application of ZnO and Fe₃O₄ Nanostructured Materials via Pyrolysis of Oleat-based Organometallic Compound
PoiSim Khiew1*, WeeSiong Chiu2, ThianKhoon Tan1, Shahidan Radiman3, Roslan Abd-Shukor3, ChinHua Chia3
1 Fac. Engineering, Uni. Nottingham Malaysia Campus
3 Sch. Applied Physics, Fac. S&T, UKM

Abstract

Magnetic and semiconductor nanomaterials exhibit novel magnetic and optical properties owing to their unique size and shape-dependent effects. With shrinking the size down to nanoscale region, various anomalous properties that normally not present in bulk start to dominate. Ability in harnessing of these anomalous properties for the design of various advance electronic devices is strictly dependent on synthetic strategies. Hence, current research focused on developing a rational synthetic control to produce high quality nanocrystals by using organometallic approach to tune both size and shape of the nanomaterials. In order to elucidate the growth mechanism, transmission electron microscopy was employed as a powerful tool in performing real time-resolved morphologies and structural characterization of magnetic (Fe₃O₄) and semiconductor (ZnO) nanocrystals. We have found that oleic acid is an effective capping ligand in preparing oxide-based nanostructures without any agglomerations, even at high temperature. The oleate-based precursors and capping ligands are fatty acid compounds, which are respectively originated from natural palm oil with low toxicity. In comparison with other synthetic approaches in producing nanostructures, current synthetic method offers an effective route to produce oxide-based nanomaterials with well-defined shapes and good monodispersity. The nanocystals are well-separated with each other without any stacking effect. In addition, the as-synthesized nanopellets are more stable both chemically and physically if compared to those nanomaterials that are previous reported. Further development and extension of current synthetic strategy are being pursued to combine both of these materials into nanocomposite form that will be use as ¡°smart magnetic nanophotocatalyst¡± for industry waste water treatment system.

Keywords : Organometallic Synthesis, Crystal morphology, Growth from solution, Soft Chemistry

Effect of Neutron Radiation on Physical Properties of Carbon Nanotubes
Yusof Abdullah, Mohd Reusmaazran Yusof, Saifollah Abdullah, Nurazila Mat Zali,Azali Muhammad, Nadira Kamarudin, Wilfred Sylvester Paulus and Zaiton Selamat
Malaysian Nuclear Agency, Bangi, 43000 Kajang Selangor, Malaysia

Abstract

Research interest for carbon nanotube (CNT) has been found to be one of the promising in various fields such as nanoelectronic devices, sensors and structural components due to its unique properties. In this paper,the effect of neutron radiation on physical properties of carbon nano tube (CNT) characterize by scanning electron microscopy (SEM),transmission electron microscopy (TEM) and x-ray diffraction (XRD)will be presented. Study also investigated on the effect of the annealing temperature at 800 °C, 900 °C and 1000 °C before radiation exposure. The results indicated that after neutron irradiated, structure damaged and modification clearly observed at crystallite size structure.

Keywords :

DEVOLOPMENT AND CHARACTERIZATION OF HA-ZrO₂ COMPOSITE 
Rusnah. M and Andanastuti. M
Material Technology Group (MTEG) , Industrial Technology Division,
Nuklear Malaysia,
Department of Mechanical and Materials Engineering, Universiti Kebangsaan Malaysia,
43600 UKM Bangi, Selangor D.E.

Abstract

Hydroxyapatite (HA)- Ca10(PO4)6(OH)2 is a type of biomaterial ceramic which has chemical and mineralogical similar to the component/substance of natural bone is made. This experiment has been conducted to produce the composite of HA-ZrO2 and to study its characteristics. In this experiment, hydroxyapatite has been synthesized by using precipitation method. The hydroxyapatite then is mixed with commercial ytria stabilized zirconia. The effect of ratio percentage composite HA-ZrO2 mixture has been investigated. Zirconia percentages are 40% and 60% was mixed with HA. Also, the different times of milling process for all samples are being investigated. The samples obtained are analyzed to get its chemical composition and its morphological structure. The analysis has been conducted in labs in Nuclear Malaysia Agency. The characterization of samples has been experimented by using Scanning Electron Microscope-Energy Dispersive X-Ray Spectroscopy (SEM-EDX), X-Ray Diffractometry (XRD) and Fourier Transform Infrared Spectroscopy (FTIR).

Keywords : Hydroxyapatite ,composite, HA-ZrO₂ and characterization

Microstructure Characterization on Aluminum Alloy 7075 Possess Retrogression and Re-Aging Heat Treatments through Optical and Scanning Electron Microscopy
NG GUAN YAO, DR. MOHD WARIKH BIN ABD RASHID, PROF. DR. ZOLKEPLI BIN BUANG
DT1778, Jalan Angkasa Nuri 22,
Taman Angkasa Nuri,
76100 Durian Tunggal, Melaka

Abstract

Aluminum Alloy 7075 is a relatively soft metal as compare to steel, thus, it requires different sample preparation and etching technique. The first objective of this study is to characterize the microstructure alteration of the alloy after various types of retrogression and re-aging heat treatments. Whereby, the second objective is to review an effective sample preparation and etching technique from the experienced by the author. First, the alloy specimens were heat treated accordingly at different retrogression parameters (165/185/205oC for 10/30 minutes) and different heating mediums (air/oil), but with the same solution heat treatment (470

Keywords : Aluminum Alloy 7075, Retrogression, aging, keller's etch, microstructure, SEM, EDX, heat treatment, precipitation, oil retrogression, retrogression and reaging, RRA, T6, T73

Die Compaction of Iron Powder at Various Temperatures: An Experimental Investigation
M. M. Rahman, S. S. M. Nor & T. J. Saktisahdan
Department of Mechanical Engineering, Universiti Tenaga Nasional
Putrajaya campus, Jalan IKRAM-UNITEN, 43000 Kajang, Selangor, Malaysia

Abstract

Powder compaction is a widely applied manufacturing process of transforming metal powder to solid engineering components by shaping the powder mass inside a rigid die. One of the key compaction parameters is the forming temperature which affects the mechanical properties and microstructures of the green compacts. Therefore, this paper aims to present the outcomes of an experimental investigation of iron powder compaction process at various temperatures. Iron powder ASC 100.29 was used as feedstock during the investigation. The forming temperature was ranged from 30°C to 200°C while the downward and upward simultaneous axial load was fixed as 130 kN. The defect-free green compacts were characterized for their relative density, bending strength, electrical conductivity and hardness, while the microstructures were analyzed through Scanning Electron Microscopy. The outcomes revealed that the green properties of powder compacts were affected by the forming temperature.

Keywords : Powder forming, green compacts, mechanical properties, microstructure

Carbon Powder as Admixed Lubricant during Warm Compaction
M. M. Rahman, T. J. Saktisahdan & S. S. M. Nor
Department of Mechanical Engineering, Universiti Tenaga Nasional
Putrajaya campus, Jalan IKRAM-UNITEN
43000 Kajang, Selangor
Malaysia

Abstract

One of the advantages of powder compaction to other manufacturing processes is the improved quality with maintained tolerances and reduced processing cost. However, during the compaction phase, significant friction force is usually generated which gives adverse effect to the quality of final products. Polymeric lubricant is usually used to reduce friction, both inter-particle and between powder mass and the die surface. However, due to its lower melting temperature, during the sintering process, portion of the lubricant at the surface is burnt out and the trapped lubricant inside the compact expands leaving pores which lowers down the strength of the sintered products. In order to overcome this problem, fine activated carbon powder varying from 0.3 to 0.5 % is used as admixed lubricant. The feedstock was prepared by mechanically mixing iron ASC 100.29 powder with designated carbon powder for 30 minutes. Powder mass was compacted at 30°C and 150°C by applying simultaneous downward and upward load of 130 kN. The defect-free green compacts were sintered at argon gas fired sintering furnace at different sintering schedule. The sintered products were tested mechanically and their microstructures were evaluated. The results revealed that the properties of sintered products were affected by carbon content, forming temperature, and sintering schedules.

Keywords : Carbon powder, sintering schedule, mechanical properties, microstructure

Morphological Study of Thermally Evaporated Copper Tin Selenide Thin Films Annealed at Different Annealing Temperature
Mohd Amirul Syafiq Mohd Yunosbase^1,2,*, Zainal Abidin Talibbase², Wan Mahmood Mat Yunusbase^2
1Industrial Technology Division, Malaysian Nuclear Agency,
43000 Kajang, Selangor Darul Ehsan, Malaysia.
²Department of Physics, Faculty of Science, Universiti Putra Mala
43400 UPM Serdang, Selangor Darul Ehsan, Malaysia.

Abstract

A development of Copper Tin Selenide (Cubase₂SnSebase₃) has become one of an important issue nowadays due to their unique physical properties which make them suitable candidate for a wide variety of applications especially in photovoltaic and solar cell applications. The main agenda of this research is to investigating the morphological properties on copper tin selenide thin films before and after annealed at different annealing temperatures. Thermal evaporation methods were employed to prepare copper tin selenide thin films onto well-cleaned glass substrates in pressurized chamber near 5.0 x 10base^-5 mBar. Six varies annealing temperatures were chosen which are 100°C, 200°C, 300°C, 400°C and 500°C for annealing process. The structural and morphological properties of annealed copper tin selenide were successfully investigated using surface profilometer, atomic force microscope (AFM), scanning electron microscope (SEM) and energy dispersive x-ray (EDX). Thickness measurement of annealed Cu2SnSe3 thin film revealed that increasing the annealing temperature has decreased the thickness of the films range from 1390 to 1800nm. When annealing temperature increase, the film shows some cracks at the surface believed cause by surface tension and stress after annealed at higher temperature. This phenomenon was agreed with atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis data.

Keywords : (Cubase₂SnSebase₃), Thin Film, Thermal Evaporation, Annealing Temperature, Morphology

Effect of compatibilizer on morphology and mechanical properties of waste natural rubber latex and polystyrene blends
O.BOONDAMNOEN¹, A.R. AZURA¹, M. OHSHIMA², S. CHUAYJULJIT³, A. ARIFFIN^1*
1School of Materials and Mineral Resources Engineering, Universiti Sa
²Department of Chemical Engineering, Kyoto University 615-8510, Japan
³Department of Materials Science, Chulalongkorn University, 10330, Th

Abstract

The styrene-co-maleic anhydride (sty-MA) and styrene-butadiene-styrene copolymer (SBS) were used as compatibilizers in waste natural rubber latex/polystyrene (WNRL/PS) blends. Theses blend were prepared through melt mixing technique using Haake internal mixer at 140 ^ºC, 60 rpm with the blend ratio of 30/70 WNRL/PS. The mechanical properties were compared with the blend without compatibilizer. The tensile fracture surface were observed using scanning electron microscope (SEM). The addition of both compatibilizers improved the mechanical properties of the WNRL/PS blends. The blend with sty-MA gave highest tensile strength and the blend with SBS gave excellence elongation. The SEM micrograph of the blend with sty-MA shows the evidence of debris indicating the stiffness behavior and the SEM micrographs of the blend with SBS shows the evidence of tendrils indicating the toughness behavior.

Keywords : Waste Natural Rubber Latex, compatibilizer,blend

Preparation and characterization of Treated Waste Natural Rubber Latex/Polystyrene Blend
O.BOONDAMNOEN¹, A.R. AZURA¹, M. OHSHIMA², S. CHUAYJULJIT³, A. ARIFFIN^1*
1School of Materials and Mineral Resources Engineering, Universiti Sa
²Department of Chemical Engineering, Kyoto University 615-8510, Japan
³Department of Materials Science, Chulalongkorn University, 10330, Th

Abstract

The waste natural rubber latex was treated with natural latex (TWNRL) prior to blend with polystyrene (PS). The blend was conducted with the ratio of 70/30 TWNRL/PS using Haake internal mixer at 140 ºC and 60 rpm. The waste natural rubber latex/PS (WNRL/PS) was prepared in the same conduction for comparison. The mechanical properties were investigated, the crosslinking density was determined applying Flory-Rehner equation and tensile fracture was observed using scanning electron microscope (SEM). The results show that TWNRL/PS blend gave lower crosslinking density, slightly lower tensile strength but excellent elongation than untreated waste natural rubber latex/PS blend (WNRL/PS). It is conjectured that the rearrangement of some rubber chains happen in TWNRL under stress. The SEM micrograph of TWNRL/PS blend shows tendrils with crossing the fracture plane indicating higher strain comparing to SEM micrograph of WNRL/PS blend.

Keywords : Treated Waste Natural Rubber Latex, blend, fracture surface

Effect of ball milling time on the morphological behaviour of banana stem powder dispersion
A. S. Siti Nuraya¹, A. Baharin¹, A. R. Azura^2
1 School of Industrial Technology, Universiti Sains Malaysia, 11800 Minden, Pula
² School of Materials and Mineral Resources Engineering, Universiti Sains Malays

Abstract

Banana stem powder was soaked in 2% of sodium hypochlorite solution for 24 hours at 40°C then ball milled at variable milling time (0 hour, 24 hours, 48 hours and 72 hours) to produce banana stem powder dispersions with variable particle size. The effect of ball milling time on the particle size and morphology of the banana stem powder particles was examined. Results showed the mean particle size of the banana stem powder reduced progressively with milling time. Transmission electron microscopy (TEM) images showed that milling the banana stem powder at 24 hours resulted in the formation of fibre whiskers around the banana stem powder particles. The TEM images for banana stem powder milling longer than 24 hours resulted in the formation of less fibre whiskers due to the breakage on the whiskers from the particles due to the mechanical shearing in ball milling. Ball milling process effectively produces the fibre whiskers around the banana stem powder particles at 24 hours of milling time.

Keywords : banana stem powder, ball mill, fibre whiskers, particle size

Effect of banana stem powder, calcium carbonate and colloidal silica on mechanical properties of natural rubber latex films 
A. S. Siti Nuraya¹, A. Baharin¹, A. R. Azura^2
1 School of Industrial Technology, Universiti Sains Malaysia, 11800 Minden, Pula
² School of Materials and Mineral Resources Engineering, Universiti Sains Malays

Abstract

Plant fiber is mainly composed of highly crystalline cellulose that reinforced with amorphous lignin and / or hemicelluloses matrix. Both crystalline and amorphous regions were responsible in an enhancement of the mechanical properties of the prevulcanized NRL films. In this study, surface modified of banana stem powder with 2% of sodium hypochlorite solution was used as reinforcing filler in the NRL compound. In comparison with other commercial fillers such as calcium carbonate and colloidal silica, the mechanical properties of the banana stem powder filled NRL films are comparable to commercial fillers. From the Transmission electron microscopy (TEM) images, showed the fillers have different particle size, shape and distribution. The irregular shape particles and the formation of fibre whiskers around the banana stem powder particles are responsible for the improvement in the interaction between the banana stem powder particles with the latex rubber matrix.

Keywords : prevulcanized natural rubber latex, banana stem powder, calcium carbonate, colloidal silica, mechanical properties.

SYNTHESIS OF CARBON NANOTUBES : Chemical Vapour Deposition (CVD) Technique
A.Azniza , M.Nuzaihan and M.Asyraf.B.A.Z
Institute of Nano Electronic Engineering (INEE)
University Malaysia Perlis (UNiMAP)
Lot 106,108 & 110, Tingkat 1, Blok A,
Taman Pertiwi Indah,
Jalan Kangar - Alor Setar, Seriab,
01000 Kangar, Perlis

Abstract

Carbon nanotubes are tiny hollow cylinders, made from a single graphene sheet, that possess many amazing properties. Another reason why nanotubes have generated intense research activities from scientists of various disciplines is the represent a new class of materials for the study of one-dimensional physics. In this research we investigate the Carbon Nanotubes (CNTs) synthesis by using chemical vapor deposition technique (CVD).The CVD method has been shown as the best method to produce CNTs in large scale. The goal of this research are to synthesize and produce below 100nm carbon nanotubes (CNTs) using low temperature chemical vapor deposition (LTCVD) below 450⁰C. Initially, the top of silicon wafer are coated with nickel which are the catalyst. Ethanols are used as carbon source and argon as the gas source. These LTCVD process are repeated by using different catalyst, carbon source, temperature and gas flow rate to achieve the goal of this research.

Keywords : Carbon nanotubes (CNTs), Chemical Vapor Deposition (CVD), Low Temperature Chemical Vapor Deposition LTCVD

SERIAL MIRO CT ANALYSIS CONFIRMS THE PROGRESSION OF TOOTH TISSUE FORMATION IN NUDE MICE
M Nur Raihanah *,**, B Safura***, A Mahyuddin*** , AJ Mohd Nazimi****, MK Khairil Aznan*****, QZ Jasmina***, N Rifqah****, BHI Ruszymah*,**, MB Marina******, R Ramli****
*Tissue Engineering Centre, Faculty of Medicine, Universiti Kebangsaan Malaysia
**Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia
*** Department of Operative Dentistry, Faculty of Dentistry of Universiti Kebang
****Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Universi
*****Department of Orthodonthics, Faculty of Dentistry, Universiti Kebangsaan Ma
******Department of Oral Biology, Universiti of Malaya

Abstract

As we aged, some of us will lose teeth due to disease, injury or simple daily wear. In this study, our objective was to develop dental hard tissue by using collagen scaffold as biomaterial. Three- to- five days post-natal (dpn) Lewis rat tooth bud cells were seeded onto 3mm x 5mm collagen scaffold. Fibrin was used to coat the collagen scaffold. The tooth construct were grown in the subcutaneous of nude mice for 8 weeks and then harvested. Micro CT-Scan was done to monitor hard tissue formation at 4, 6 and 8 week. H & E staining and immunohistochemistry was done for hard tissue characterization. Micro CT Scan image showed hard tissue formation from week 4 and volume and density of hard tissue increases with observation period. This result were strongly support by immnunohistochemistry results which show positive expression of AMELX (biomineralization of teeth), Periostin (osteoblast specific antibody) , PCK-26 (identify epithelial cell) and vimentin (mesenchymal cell). These results suggested that collagen as scaffold is a suitable for tooth tissue engineering. In conclusion, micro CT is a valuable tool for observe the progression of tissue formation non – invasively that will reduce the use of animals and give more consistent data in tissue engineering research.

Keywords :

SYNTHESIS AND ASSEMBLY OF ELECTRODEPOSITED MAGNETIC NANOWIRES
Nur Ubaidah Saidin, Kok Kuan Ying and Ng Inn Khuan
Materials Technology Division, Malaysian Nuclear Agency,
Bangi, 43000 Kajang, Selangor.

Abstract

Electrochemical deposition has been employed to synthesize various types of one-dimensional nanowires arrays to meet different requirements for applications. This study focuses on synthesis of high aspect ratio magnetic nanowires in the form of homogeneous such as Ni and multilayered structures such as NiFe/Cu using template-directed electrochemical deposition techniques. The template is fabricated using anodisation of aluminium to form well aligned pores structure. To assemble single nanowire on prefabricated electrodes with good electrical contact, magnetic or a.c. delectrophoretic techniques were used. The versatility of these approaches is based on the high controllability achieved by varying the magnetic field or electric field strength. These assembly techniques allow us to investigate the magnetotransport properties of a single nanowire without the dipolar interactions between wires.

Keywords : Electrodepostion, nanowires assembly, magnetic alignment

Quantitative Histological and Histochemical Studies of Different Muscles of Lower Limb in Diabetes Mellitus Cases
Dr Wan Muhamad Salahudin, Asst Prof Dr Ye Tun, Assoc. Prof Dr Ahmad Hafiz Zulkifli
Basic Medical Science Department, Kulliyyah of Medicine
Orthopaedic Department, Kulliyyah of Medicine
International Islamic University of Malaysia

Abstract

Background: Diabetes mellitus causes several changes in fiber size and oxidative capacity in skeletal muscle. Gastrocnemius, Soleus and Anterior Tibialis muscle are important leg muscles involve in reconstruction of amputation stump. The fiber size and oxidative enzyme are important factors related to the viability of muscle and subsequently stump healing. Aim of the study: To describe the fiber size and oxidative capacity quantitatively in 3 muscles of the leg Materials and methods: Specimen obtained from the 10 diabetes mellitus subjects undergone below knee amputation (BKA). Specimen was stained for enzyme histochemistry NADH-TR staining. The slide was analyzed with ImageJ software for fiber type distribution and oxidative capacity based on staining density. Result and discussion: Gastrocnemius muscle has predominantly Type 1 muscle fibers and highest oxidative capacity, while the anterior tibialis muscle has predominantly Type 2 muscle fibers and lowest oxidative capacity. Soleus muscle has almost equal Type 1 and 2 muscle fibers and has intermediate oxidative capacity. Conclusion: Muscle with predominant type 1 fibers has highest oxidative capacity.

Keywords : Keywords: oxidative capacity, diabetes mellitus, skeletal muscle

THE ESSENTIALITY OF LEUKEMIA INHIBITORY FACTOR (LIF) IN MAINTAINING THE PLURIPOTENTIALITY OF FULL TERM RAT AMNIOTIC FLUID STEM CELLS
.1,2N. Nordin, 1,2M.F. Hoo, 1,3R. Rajesh, 4P.K. Cheah, 1,2S. Abdullah
1Stem Cell Research Laboratory, .
3Department of Pathology,
4Department of Human Anatomy,
Faculty of Medicine & Health Sciences
Universiti Putra Malaysia

Abstract

Stem cell research has gained worldwide attention with astounding findings for potential use in therapeutic application from various sources including mid- and full-term amniotic fluid. In 2008, c-kit (a marker for stem cell receptor) positive cells with high differentiation potential were successfully isolated from rat full term amniotic fluid. These cells were found to express pluripotency marker, Oct4, and the telomerase reverse transcriptase gene, tert, and to form multicellular aggregates, embryoid bodies (EBs), suggestive of their high potency. LIF has been known to be essential in maintaining the pluripotency of other type of pluripotent stem cells such as embryonic stem (ES) cells and induced pluripotent stem (iPS) cells. However, no studies have indicated the importance of LIF in maintaining rat amniotic fluid stem (AFS) cells/ c-kit positive cells. Here, we aim to seek this out. Interestingly, we found that the addition of LIF in the culture medium of rat c-kit positive cells has contributed to the maintenance of pluripotency, as Oct 4 and Sox 2 expression are maintained. Upon prolonged withdrawal of LIF, these cells were observed to gradually diminish its differentiation potential upon directed differentiation into specific lineage of each primary germ layer. Hence, we believe LIF is playing an essential role in conserving the pluripotency of rat full term amniotic fluid stem cells.

Keywords : Amniotic fluid, amniotic fluid stem cells, full term, pluripotency

The Effect of ZnO Nanoparticles on Phenol Red
Tan Thian Khoon
University of Nottingham Malaysia Campus,
Faculty of Engineering,
Jalan Broga, 43500 Semenyih,
Selangor.

Abstract

This study has investigated the effect of Phenol Red (PR) in the presence of ZnO nanoparticles in the aqueous solutions with UV light irradiation. ZnO has been considered because it has been reported that ZnO is a suitable replacement for TiO2 in certain application. The characterization of ZnO photocatalyst were X-ray diffraction (XRD), transmission electron microscopy (TEM), specific surface area analysis (BET), and UV-visible spectroscopy. X-ray diffractometry result for the ZnO nanoparticles exhibit normal crystalline phase features. All observed peaks can be indexed to the pure hexagonal wurtzite crystal structures, with the space group of P63mc. From XRD pattern, no diffraction peaks from other impurities have been observed. In addition, TEM measurement shows that most of the nanoparticles are spherical and rod-like in shape and fairly monodispersed. A significant degradation of the PR was observed in the presence of the catalyst without the irradiation of the UV light and the degradation increases significantly when irradiated for certain period with the UV light. Besides, for the same period of irradiation, the photodegradation of PR increases as the photocatalyst loading was increased. The BET measurement for the surface area for ZnO was 11.9 m2/g. Few parameters were also investigated in this study such as initial PR concentration, photocatalyst loading and pH were also determined.

Keywords : Nanostructures, Phenol Red, Zinc Oxide, Heterogeneous Photocatalyst

Characterization of baby talc powder in Thailand’s market
P. Chetanachan1 , P. Dararutana2
1 National Institute of Health, Department of Medical Sciences, Nonthaburi, 1100

Abstract

It is well-known that asbestos is a fiber causing lung diseases. It is a generic term for several types of naturally occurring fibrous silicate minerals. Baby talc powder is used for preventing diaper rash, as a deodorant. It may be composed of talc which is a mineral composed of hydrated magnesium silicate. SEM-EDS was carried out to study the structure and composition of baby talc powder samples that sold in markets. Like-asbestos structures were found to distribute in some samples. Their compositions were mainly contained with silica and magnesium. More details will be discussed.

Keywords : Baby talc powder, Asbestos, SEM-EDS

MICROWAVE SINTERING OF CALCIUM PHOSPHATE CERAMICS
 Radzali Othman and Azlila Zakaria
Rekagraf Laboratory,
School of Materials & Mineral Resources Engineering,
Engineering Campus, Universiti Sains Malaysia,
14300 Nibong Tebal,
Penang,
MALAYSIA.

Abstract

Specimens of a calcium phosphate powder, compacted at 86 MPa, were sintered at two sintering temperatures of 1000^oC and 1100^oC using a microwave furnace. Determination of the physical (shrinkage, porosity and density) and mechanical (hardness) properties of the specimens obtained were carried out, and compared to specimens of similar composition which had also been sintered at the same temperatures using a muffle furnace for comparative purposes. Microstructural examinations by optical microscocopy (OM) and scanning electron microscopy (SEM) were conducted to ascertain the difference in properties observed.

Keywords : Microwave sintering, Calcium Phosphate, Precipitation, Hardness

-SILICA GLASS-CERAMICS USE OF RICE STRAW ASH IN ENHANCING THE PROPERTIES OF SODA-LIME

O. Radzali* and J. Farah.
School of Materials and Mineral Resources Engineering,
Engineering Campus, Universiti Sains Malaysia,
14300 Nibong Tebal,
Pulau Pinang, Malaysia.

Abstract

A study on the crystallization behavior of a soda-lime-silica glass composition incorporating rice straw ash was carried out. Melting was carried out at 1500oC in an alumina crucible for 5 hours. The glass produced was examined by differential scanning calorimetry to determine the glass transition and crystallization temperatures for use as heat-treatment temperatures to transform the glass into glass-ceramics. A similar composition made up using industrial chemicals was also melted for comparative purposes. Both glasses were heat-treated at 750oC and 920oC for 3 different soaking durations. Both glasses exhibited crystallization from the outer surface which increased in thickness as the soaking time was increased. Scanning electron microscopy was used to study the thickness and identity of the crystalline phases formed. Density and hardness measurements showed that the rice straw glass ceramics exhibited higher values than the glass-ceramics using industrial chemicals. The morphologies of the fracture surfaces of both glass-ceramic compositions were also evaluated by scanning electron microscopy.

Keywords : Rice straw, Glass-ceramic, Ashing, Glass melting, Heat-treated

SEM, TEM & XRD CHARACTERIC ANALYSIS OF RUTILE AND ANATASE NANOTITANIA PRODUCED FROM TITANIUM MINERAL
Meor Yusoff M. S., Mahdi E. Mahmoud, Masliana Muslimin, Sarimah Mahat and Wilfred Paulus
Industrial Technology Division
Malaysian Nuclear Agency,
Bangi, 43000 Kajang, Selangor, Malaysia

Abstract

Titania (TiO₂) is a compound that is both familiar and abundant, having seen many applications in diverse areas such as cosmetics, coatings and water purification. This attribute is mainly due to the flexibility of titania as a compound, where it comprise of many unique phases and crystal systems that is responsible for its behavior in certain conditions. Titania comprises of eleven phases (some only exist in high pressure states), and four crystal systems (orthorhombic, monoclinic, tetragonal and cubic). The two most common phases of titania are anatase and rutile. In this this paper we have used a local titanium mineral called synthetic rutile as the starting material to produce both of these phases in nanoscale form. Characteristic methods such SEM, TEM and XRD were used in identifying the different crystalline form as well inspecting the difference in nanostructure of the rutile and anatase phases.

Keywords :

TiO₂ NANOTUBE ARRAYS: EFFECT OF SUBSTRATE THICKNESS AND CLEANING AGENT
Khairul Arifah Saharudin, Srimala Sreekantan
School of Materials & Mineral Resources Engineering,
Universiti Sains Malaysia Engineering Campus,
14300, Nibong Tebal, Penang, Malaysia

Abstract

In this paper, anodization of Ti foil was carried out in ethylene glycol (EG) containing 5 wt% NH4F solution and 1 wt% of water at 60 V for 60 min. The substrate thickness and the different cleaning agents were investigated. The crystal structure was studied by X-Ray Diffraction (XRD) analysis, and the morphology was observed via field emission scanning electron microscopy (FESEM). Nanotube arrays with length over 33 μm was obtained upon anodizing 0.025 mm thick Ti foil compared to 0.1 mm and 0.05 mm thick Ti foil. These finding shows that thin foil are preferable for the formation of TiO₂ nanotubes with a fast rate. This is due to the current density obtained are high as compared to the thick Ti foil. High current density is known to accelerate the ionization of NH₄F and the mobility of the F^-, O^2- and [TiF₆]^2- species. Therefore, the dissolution in the vertical direction into the bulk Ti is improved, thus allowing the formation of long nanotubes. Acetone and DI water were used as a cleaning agent. The nanotubular structure of TiO₂ was revealed by washing in sonicated acetone and no precipitate structure was found to remain on the surface. The as-anodized TiO₂ nanotubes were annealed at 400 °C and the photocatalytic activity of the nanotubes produced was evaluated by the degradation of methyl orange. The detail observation was discussed thoroughly in this paper.

Keywords :

The Effect Of Sintering Temperature On The Properties Of W-20 wt.%Cu Composite Produced By Liquid Phase Sintering Process 
F. Ismail¹, M.A. Selamat¹, N. Muhamad² , A.B. Sulong² and N.A. Majid<sup>1

1</sup>Structural Material Program, Advanced Materials Research Centre (AMR
²Department of Mechanical & Materials Engineering, Universiti Kebangs

Abstract

In this study, the effect of sintering temperature on the properties of tungsten-copper (W-Cu) composite produced by liquid phase sintering (LPS) process has been investigated. W-20 wt.%Cu composite powders with particle size less than 1 μm was prepared by cold compaction and followed by cold isostatic pressing. The green specimens were then sintered under nitrogen based atmosphere in the temperature range of 1100^oC to 1300^oC. The sintering studies were conducted to determine the extent of densification and corresponding to microstructure changes. In addition, the properties of the sintered specimens such as physical appearance, microstructure evolution and mechanical properties were presented and discussed.

Keywords : compaction, sintering, microstructure, densification, transverse rupture strength

Fluid delivery mechanism choice in micromixer for life science investigation
Tijjani Adam, U. Hashim

Institute Nano Electronic Engineering
Universiti Malaysia Perlis
Lot 106, 108 &110,Tingkat1, Blok A Taman Pertiwi Indah , Seriab, 01000 Kangar pe

Abstract

The paper contains report on COMSOL Multiphysics model simulation of a micromixer that takes the advantage of electroosmosis to mix fluids. Microlaboratories for biochemical applications often require rapid mixing of different fluid streams. At the microscale, flow is usually highly ordered laminar flow, and the lack of turbulence makes diffusion the primary mechanism for mixing. While diffusional mixing of small molecules (and therefore of rapidly diffusing species) can occur in a matter of seconds over distances of tens of micrometers, mixing of larger molecules such as peptides, proteins, and high molecular-weight nucleic acids can require equilibration times from minutes to hours over comparable distances. Such delays are impractically long for many chemical analyses. These problems have led to an intense search for more efficient mixers for microfluidic systems most microscale mixing devices are either passive mixers that use geometrical stirring or active mixers that use moving parts or external forces, such as pressure or electric field. In a passive mixer, one way of increasing the mixing is by “shredding” two or several fluids into very thin alternating layers, which decreases the average diffusion length for the molecules between the different fluids. Another way of improving mixing efficiency is to use active mixers with moving parts that stir the fluids. At the microscale level moving parts in an active mixer are very fragile. One alternative is to use electroosmotic effects to achieve a mixing effect that is perpendicular to the main direction of the flow.

Keywords : Comsol Multiphysics, Microlaboratories, Biochemical, Nuclei acid, simulation, electroosmosis, Microfluidics

PREPARATION AND CHARACTERIZATION OF AQUEOUS ALUMINA FEEDSTOCK FOR INJECTION MOULDING PROCESS
W. D. Teng and Saidin Karim
Structural Materials Programme
Advanced Materials Research Centre (AMREC), SIRIM Berhad
1 Persiaran Dato’ Menteri, 40911 Shah Alam

Abstract

The alumina-agarose based feedstock materials were prepared as aqueous ceramic feedstock for injection moulding. Various amounts of binders were formulation and prepared by using z-blade mixer. The feedstock was characterised by capillary rheometer for the feasibility of injection moulding process. The compact was debound and sintered to 1400-1600^oC. The sintered compact was characterised and presented as density, flexural strength and porosity with related to the microstructure examined by SEM. It had shown that the aqueous alumina feedstock is environmental friendly to fabricate the product by injection moulding process.

Keywords :

SCANNING ELECTRON MICROSCOPY FOR IDENTIFICATION OF PAPER STRENGTH DEVELOPMENT BY TWO VARIATIONS OF REFINER PLATE PATTERN
Yunita Megasari Dermawan and Arniza Ghazali
School of Industrial Technology
Universiti Sains Malaysia
11800 USM
Penang
Malaysia

Abstract

The abundant oil palm Empty Fruit Bunch (EFB) was used as raw material in the low-cost, low environmental impact Alkaline Peroxide Pulping (APP) to produce pulp and paper. Pulping was performed by using two types of refiner plate pattern, 12716 and D2A505. For each plate pattern, samples were prepared by treatment with 2:2.5% (wt/wt) alkali-to-peroxide (AP) ratio applying different number of AP impregnation stages. For plate 12716, the resultant papers show tensile strength varying from 6.9 Nm/g to 16.22 Nm/g, tear strength varying from 3.6 mN•m²/g to 5.2 mN•m²/g and folding endurance varying from 2 to 25. As of plate D2A505, tensile strength of papers made from the produced pulp range from 6.93 Nm/g to 29.77 Nm/g, tear strength from 2.9 mN•m²/g to 5.34 mN•m²/g, and folding endurance from 2 to 1633. Examination of paper surface by Scanning Electron Micrograph (SEM) revealed an increase in the extent of what appeared under SEM as ‘fibre coalescence’, implying extensive overlapping and bonding between the produced pulp. For all sets of lower strength pulp network, the produced fibrous mass was predominantly fibre bundles without any sign of coalescence. SEM analysis also witnessed correlation between the presence of long individual fibres and fibre bundles having correlation with paper resistance to burst and folding. The established correlations demonstrate the important way scanning electron microscopic technique serve for comprehensive understanding of fiber and fiber bonding characters in paper quality assessment.

Keywords : alkaline peroxide pulping, APMP, EFB, impregnation, paper properties, SEM

Nanowire fabrication: Design consideration for repeatability and reliability in pattern transfer.
Tijjani Adam, U. Hashim

Institute Nano Electronic Engineering
Universiti Malaysia Perlis
Lot 106, 108 &110,Tingkat1, Blok A Taman Pertiwi Indah , Seriab, 01000 Kangar pe

Abstract

In fabrication of Nanowire, alignment and exposure are the most critical steps in photolithography process, the resolution requirements and precise alignment are vital, each mask needs to be precisely aligned with original alignment mark. Otherwise, it can’t successfully transfer the original pattern to the wafer surface causing device and circuit failure. Precise transfer of pattern transfer means guarantee in high repeatability and reliability, high throughput and low cost of ownership. By improving this resolution and alignment precision the minimum size can be further reduced to 1nm and beyond and other important aspect of achieving minimum precised size is, the photo resist must be very sensitive to the exposure light to achieve reasonable throughput. However, if the sensitivity is too high, other photoresist other characteristics can be affected, including the resolution. In this study, we have 3 pattern transfer process steps to fabricate Nanowire, each one was precisely aligned with the previous to achieve successful pattern transfer in our design. There was a very little room for alignment error and we were able to achieved less than 2% error of the critical dimension

Keywords : Pattern transfer, Nanowire, fabrication, precision, alignment, critical dimension

THE EFFECT OF IMPACT MODIFIERS ON THE POLYLACTIC ACID-REINFORCED KENAF BAST FIBER COMPOSITE
Husna Madihah Hasan, Razaina Mat Taib
School of Materials and Mineral Resources Engineering,
Engineering Campus, Universiti Sains Malaysia,
Seri Ampangan,
14300 Nibong Tebal,
Seberang Prai Selatan, Penang, Malaysia

Abstract

Natural fiber-reinforced polymer composites are in high demand because of its advantages such as excellent mechanical properties, low cost and low density. To toughen the PLA matrix, impact modifier was blend with neat PLA first, then kenaf were mixed vigorously. Both studies were done in internal mixer at 185 ^oC and 50 rpm. The compositions of impact modifier were 10, 20, 30 and 40 wt%. The effect of impact modifier in toughening the composites was studied by using tensile, charpy impact and DMA testing. The fractures surfaces of tensile specimen were examined by using Scanning Electron Micrograph .Tensile strength and modulus of the composites decreased with addition of impact modifier. In contrast, the elongation at break and impact strength was increase.

Keywords : Poly(lactic acid), impact modifier, kenaf, impact strength

GROWTH OF ANODIC POROUS ALUMINA IN OXALIC ACID
NUR HAFIZA BINTI MOHD NAJIB
Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Lot 108, T

Abstract

In this research, a nanoporous anodized aluminum oxide AAO thin film was successfully grown onto oxide layer on silicon substrate. The anodization of Si/SiO₂/Al substrate was conducted in a vigorous stirring oxalic acid bath solution. The rate of growth, morphology, kinetic study and the chemical composition of the AAO thin film were investigated. The resulting array, pores structure and pores density of AAO strongly depends on the anodizing parameters. The anodizing cell was done by varying the operating voltage from 40V to 55V and the bath temperature from 10^oC to 25 ^oC in a vigorous stirring of C₂H₂O₄ oxalic acid bath solution. The duration of anodizing process was remain constant for 1 hour. Morphology of AAO thin film and AAO phases were observed by using the scanning electron microscopy SEM and X-Ray Diffraction (XRD. From this study, the optimum parameters for having well ordered porous AAO have been discovered.

Keywords : ANODIC POROUS ALUMINA,OXALIC

SILICA OF THE OIL PALM EMPTY FRUIT BUNCHES - AN INFINITE AMAZEMENT 
ARNIZA GHAZALI ¹, SALMI GHAZALI², WAN ROSLI WAN DAUD^1
1SCHOOL OF INDUSTRIAL TECHNOLOGY (BPC), UNIVERSITI SAINS MALAYSIA
11800 USM, PENANG, MALAYSIA.
²Faculty of Engineering, Universiti Putra Malaysia,
43400 Serdang, Selangor, Malaysia

Abstract

The abundance if silica in plants is understood to fit many purposes. In the oil palm empty fruit bunches that was initially intended for extraction of paper making fibres, silica was found to range between 10-20 µm, effectively removed by mechanical impacts. Removal of silica was interestingly aided by chelation with DTPA and this provides evidence of the adjacent of the mineral to the silica bodies. Despite removing 70% of the micro-bodies, the treated biomass revealed the presence of 0.3% (wt/wt) of residual silica. Scanning electron microscopy of the ash of the EFB cellulose mass unveiled the presence of siliceous thread amidst the common micro-bodies. SEM examination of the alpha cellulose and ash of the pulp derived from the biomass presents evidence of siliceous fluid transport structures, believed to be part of the skeletal silica in the fruit bunch structure of the palm. The smorgasbord shapes and sizes of the found siliceous structures in EFB and the various derivative ashes reflects nature¡¦s amazing craftsmanship of living things for serving specific functions such as mechanical, aesthetical, defense and other infinite purposes.

Keywords : EFB, pulp, paper, oil palm biomass, silica

CHARACTERISATION OF PAPER WITH A BROAD SPECTRUM OF QUALITY USING SCANNING ELECTRON MICROSCOPY 
ARNIZA GHAZALI*, MOHD RIDZUAN HAFIZ MOHD ZUKERI, NURUL HASANAH KAMALUDDIN, ROSNAH MUHD YUSOFF, MUMAMMAD AL-AMIN ZAINI, YUNITA MEGASARI DERMAWAN and WANROSLI WAN DAUD
School of Industrial Technology,
Universiti Sains Malaysia,
11800 USM, Penang, Malaysia

Abstract

ABSTRACT Pulp, the raw material for making paper, was produced from the residue of cash crop, the oil palm biomass. Fibre extraction was performed by environmentally compatible alkaline peroxide pulping (APP), applying varying mildness of alkali-to-peroxide ratios ranging from 1:1.5% (wt/wt), 2:2.5% (wt/wt), 4:5% (wt/wt) to 8:10% (wt/wt). The purpose of this variation was to assess the quality of paper versus fiber characteristics achievable for APP complying 10-to-1 liquor-to-biomass ratio. Tensile strength of the produced paper lies within the 3.6 mN•m²/g to 73 mN•m²/g range, portraying a broad spectrum increase in paper quality. It is evident from scanning electron microscopy (SEM) that paper quality improved by the extent of biomass fibrillation and length of the fibers. High quality papers, however, was also found to contain fines elements and these correlate with the increasing extent of ‘fibre coalescence’ found to be attributable to the fines’ inter-fiber gap filling roles. As a result, papers viewed under x100 magnification are devoid of well-defined fiber strips, resulting in an overall smoother, well-form appearance. It is also apparent from SEM that fines, defined as the mass escaping the 200-mesh screen, enhanced paper quality by its gluing effect in the fiber network. This correlates with the high density value, low scattering of fibers and low paper thickness depicted by SEM cross-sectional examination of high quality papers.

Keywords : Alkaline peroxide pulp and paper quality

EFFECT OF HEAT TREATMENT ON BARIUM TITANATE CERAMIC POWDERS
Nurazila Mat Zali and Che Seman Mahmood
Industrial Technology Division
Malaysian Nuclear Agency Bangi,
Bangi, 43000 Kajang, Selangor, Malaysia

Abstract

Barium Titanate (BaTiO₃) powders have been synthesized via a sol-gel route starting from soluble precursors of barium and titanium . The synthesized powders were calcined for 2 hours at temperatures between 800 to 1000 ^oC. Phase formation, crystal structure and the crystallite size of the calcined powders were investigated as a function of calcination temperature by X-Ray diffraction method (XRD). A scanning electron microscope (SEM) equipped with energy-dispersive x-ray spectroscopy (EDX) was used for determination of morphology and elemental composition. The XRD results showed that the formation of BaTiO₃ phase and BaCl₂.H₂O phase with crystallite size range of 32-140nm. The purity and crystallite size of BaTiO₃ powders were found to increase with increasing calcination temperature. Higher temperatures clearly favoured particle growth and the formation of large and hard agglomerates. The morphology of powders almost spherical in shape.

Keywords : BaTiO₃ powders, sol-gel, crystallite size, calcination temperature

Parameter Control, Characterization, and Optimization in the Fabrication of Tissue Engineering Scaffold
Yong Leng Chuan, MD Enamul Hoque and Ian Pashby
Department of Mechanical, Materials and Manufacturing Engineering
School of Mechanical Engineering
University of Nottingham Malaysia Campus
Jalan Broga, 43500 Semenyih
Selangor Darul Ehsan,
Malaysia

Abstract

One of the important aspects of tissue engineering is the architecture of designed scaffolds. For customized tissue engineering, it is essential to be able to fabricate 3D scaffolds of various pore geometry, porosity, mechanical and degradation properties, in order to repair tissue defects. Rapid prototyping or solid free-form fabrication techniques hold great promise for designing 3D customized scaffolds, yet traditional cell-seeding techniques may not provide enough cell mass for larger constructs. This paper aims to present a novel rapid prototyping fabrication method, optimization of process parameter and preliminary characterization for polycaprolactone scaffolds. A desktop robot based rapid prototyping (DRBRP) melt-extrusion technique has been developed to fabricate scaffolds for tissue engineering applications. The system is a computer-controlled three axis machine with a dispenser head and adjustable nozzle. Polycaprolactone is sequentially dispensed and allowed to contact the base. The scaffold properties were characterized by scanning electron microscopy, porosity calculation and compression test. An example of fabrication of a hybrid design scaffold is demonstrated. The applications of the scaffolds are discussed based on its potential for tissue engineering. It is shown that the DRBRP melt-extrusion technique can be interfaced with imaging techniques and computational modeling to produce scaffolds which can be customized in overall pore size and shape allowing tissue-engineered grafts to be tailored to specific applications or even for individual patients. The process parameters were found to influence the scaffold morphology. However, the pore diameters of the built scaffold were in the viable range for tissue engineering applications. The optimal set of process parameters have been concluded from this study. Important challenges for further research are the incorporation of various design, as well as various dispensing materials. Improvements regarding the mechanical properties of the scaffolds are also necessary.

Keywords : Tissue Engineering, Rapid Prototyping, Polycaprolactone, Computational Modeling, Melt-Extrusion Technique, Scaffold.

Diffusion Bonding of Sialon with SS430 Ferritic Stainless Steel
Mazlan Mohammad
AMREC, SIRIM BHD
Lot 34 Jalan HiTech 2/3
09000 Kulim

Abstract

Sialon ceramics are attractive structural materials due to their good room and high temperature mechanical properties, excellent tribological properties, excellent wear resistance, and good corrosion and oxidation resistance. However, these ceramics cannot be used alone as engineering and structural components, due to its brittleness. They are therefore normally joined to metal in order to utilise the toughness properties of metallic materials. In direct diffusion bonding of sialon to metal, ferritic stainless steel was found to be a promising candidate for metal whereby the formation of unwanted brittle hard phase was suppressed at the interface when the stainless steel is nitrided prior to bonding. The common method of diffusion bonding process is by hot pressing of the two materials at elevated temperature and pressure under vacuum. This paper highlighted the physical properties of diffusion bonded sialon with nitrided SS430 ferritic stainless steel at a bonding temperature and time of 1200^oC and 1 hour respectively. The nitriding heat treatment was performed under a mixture of 5%H₂ in N₂ at a temperature of 1200^oC for 4 hours.

Keywords : Diffusion bonding, nitriding, sialon, ferritic stainless steel

Mechanical behavior and microstructural analysis of functionalized multi walled carbon nanotubes/polypropylene composites
Ehsan Mohammadpour, Mokhtar Awang, Wei Vern Hor , Faiz Ahmad, M Zaki Abdullah
Mechanical Engineering Department
Universiti Teknologi Petronas
Seri Iskandar 31750
Perak

Abstract

This work describes the dispersion of functionalized carbon nanotubes in polypropylene. The effect of chemical and physical functionalization on the structure and morphology of multi walled carbon nanotubes (MWCNTs) were studied using FESEM, TEM imaging as well as XPS and Raman analysis. Nanocomposites containing 0.5-4 wt % MWCNTs have been synthesized via melt mixing and injection molding. The young’s modulus, tensile strength and rapture strain of the samples were investigated. Tensile tests showed increase in tensile strength for the nanocomposites that contain MWCNTs up to 2 wt%. A decrease in tensile strength was seen in samples that contain 4 wt% of MWCNTs for both raw and Triton X-100 functionalized, signifying MWCNT degradation/rebundling at composition with higher content of MWCNTs. For the acid-treated MWCNTs, however, results showed slight improvement even at 4wt%, showing a possibility of effective dispersion of MWCNTs. Fracture morphology examination of the nanocomposites revealed efficient distribution of functionalized MWCNTs within the polypropylene matrix.

Keywords : Multi walled carbon nanotube, nanocomposite, dispersion, functionalization

MORPHOLOGICAL PROPERTIES OF ELECTRON BEAM IRRADIATED POLY(VINYL CHLORIDE)/EPOXIDIZED NATURAL RUBBER BLEND IN THE PRESENCE OF VARIOUS ADDITIVES
Chantara Thevy Ratnam , Wan Ali Yusof

Radiation Processing Technology Div
Malaysian Nuclear Agency (Nuclear Malaysia),
Bangi, 43000 Kajang, Malaysia.

Abstract

The effect of irradiation on the structure of 50/50 poly(vinyl chloride)/epoxidized natural rubber blend (PVC/ENR) was studied using the scanning electron microscope studies (SEM). The 50/50 PVC/ENR blend was irradiated by using a 3.0 MeV electron beam machine at 0 and 200 kGy irradiation doses. The morphological development occurring as consequences of addition of TMPTA, TBLS and Irganox 1010irradiation-induced changes of the blend was investigated. The addition of Irganox1010 and tribasic lead sulfate were found to inhibit the irradiation-induced reaction in the blend to a considerable extent. The plasticizing effect of TMPTA prior to irradiation and the formation of microgels upon irradiation are also discussed. The tensile failure surfaces of both irradiated and unirradiated blend showed characteristic features, which could be correlated with the strength and type of failure of the blend. On irradiation the fractured surface topography changes from ductile to brittle. Keywords: Additives, crosslinking, irradiation, PVC/ENR blend, morphology. *Corresponding author

Keywords : Additives, crosslinking, irradiation, PVC/ENR blend, morphology.

The effects of HAP addition on properties and microstucture of F-75/HAP composites
Nur Maizatul Shima Adzali, Shamsul Baharin Jamaludin and Mohd Nazree Derman
Schools of Materials Engineering, University Malaysia Perlis, Kompleks Pusat Pe

Abstract

Co-Cr-Mo alloys (F-75) are widely used in biomaterials implants such as prosthetic hips and knees due to their high performance in mechanical properties, wear, and corrosion as well as biocompatibility. Hydroxyapatite (HAP) powders have been used as filler because HAP is the one of the most effective biocompatible materials with similarities to mineral constituents of bones and teeth. This research reports the effects of HAP addition on microstructure and properties of the F-75/HAP composites fabricated by powder metallurgy. HAP powders (chemical formula Ca₁₀(PO₄)₆ (OH)₂) have been added to Co-Cr-Mo alloys in composition of 0, 2, 6 and 10 wt.%. The mixtures were then milled at 154 RPM, before cold compacted at 550 MPa. Sintering was performed at 1150 C in a tube furnace with sintering time set to two hours. Physical properties were measured by means of density and porosity. A scanning electron microscope (SEM) equipped with energy-dispersive x-ray spectroscopy (EDX) was used for determination of microstructure and interface analysis. The composites with higher addition of HAP showed better density and porosity properties than those with lower addition of HAP. Line scanning analysis showed that, as the addition of HAP is increased, there was good interface bonding between HAP particles and matrix F-75.

Keywords : Co-Cr-Mo alloys, hydroxyapatite powders, sintering, microstructure, line scan analysis.

The Effects Of Synthesis Parameters On The Formation Of Gold Coated Iron Oxide Nanoparticle
Khairunisak Abdul Razak^1,2 and Sharifah Norefi Shaheera Syed Jamalluddin^2
1School of Materials and Mineral Resources Engineering,
Engineering Campus, Universiti Sains Malaysia,
14300 Nibong Tebal, Penang, Malaysia
²NanoBiotechnology Research and Innovation,
Institute for Research in Molecular Medicine
Universiti Sains Malaysia, 11800 USM, Penang, Malaysia

Abstract

This work describe the formation of gold coated iron oxide nanoparticles using two steps approach. Magnetic iron oxide nanoparticles were synthesized using the co-precipitation technique. Then, the reduction of gold shell on the surface of magnetic iron oxide nanoparticles was performed that change black colour iron oxide nanoparticles to reddish brown gold coated iron oxide nanoparticles. Several synthesis parameters were studied to obtain optimum synthesis parameters such as volume of iron oxides nanoparticles, concentration of trisodium citrate, concentration of hydroxylamine and volume of gold salt. The optimum synthesis parameters to synthesis gold coated iron oxide nanoparticles were obtained by using 30μl iron oxide seed nanoparticles, 0.5 M trisodium citrate, 0.01 M hydroxylamine and 10 ml of 0.0127 M gold salt. X-Ray diffraction spectra showed full coated of gold shell on iron oxide nanoparticles, whereby none of iron oxide spectra was detected. However, EDX analysis proved the presence of iron oxide in the sample. UV-Vis analysis showed the shifting of peaks with changing of synthesis parameters that indicated the particle size changes. TEM images showed that the size of nanoparticles changed from ~ 5.91 nm iron oxide nanoparticles to ~ 7.79 nm gold coated iron oxide nanoparticles that proved the formation of gold coated iron oxide nanoparticles with shell size of ~ 0.94 nm.

Keywords : Nanotechnology, gold nanoparticles, iron oxide

Scanning Electron Microscopy of the Red Palm Weevil (RPW), Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae): A new invasive pest of coconut palms in Terengganu
Wahizatul Afzan Azmi
Department of Biological Sciences
Faculty of Science & Technology
Universiti Malaysia Terengganu
21030 Kuala Terengganu
Terengganu

Abstract

Scanning electron microscopy was used to study and describe some of morphological characters of the Red Palm Weevil, Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae) adults from Terengganu, Malaysia. Red Palm Weevil (RPW) is a major pest of cultivated palms (oil, date and coconut palms) in many parts of the world. Recently, the Department of Agriculture of Terengganu State found the RPW causing the death of the crown of coconut palms in more than 800 locations in Terengganu. The symptoms of attack are very ambiguous and cannot be detected until the crown of the coconut palm collapsed. This invasive beetle will threaten the coconut industry and, indeed, the survival of other palms (e.g. oil palm). In present study, the morphological structures of the male and female adults of R. ferruginues were compared. Observations were focused on head, antennae, mouthparts, snout, pronotum, foreleg, elytra and pygidium. This was the first time that the morphometry analysis of the species have been reported from Peninsular Malaysia. Outcomes from this morphometric study is hoped will give a better understanding on the taxonomy of this species, and could be one of the most considerable importance to develop new control strategy of this invasive pest.

Keywords : Red Palm Weevil, Rhynchophorus ferrugineus, morphological characters, female, male

Effect Of Hot Deformation On The Microstructure Of Direct Chill Cast Al-Mg-Si Alloy
Dr. Mohd Bin Harun, *Nur Atikah Abdul Hamid, Nur Ubaidah Saidin, Nadira Kamarudin, Mohd Shariff Sattar and Zaiton Selamat.
Material Technology Group
Malaysian Nuclear Agency Bangi,
Bangi, 43000 Kajang, Selangor, Malaysia
^*Universiti Malaysia Perlis (UNIMAP)

Abstract

The effect of different relative amount of hot deformation and heat treatment on the microstructures such as porosity and grain growth has been studied in detail. The alloy used in this studied was direct chill cast Al-Mg-Si alloy which is especially used for conductor wires. The alloy has been heat treated and rolled at various deformation rates. The changes in microstructure and mechanical properties have been determined through micro hardness test and microscopic analysis. Microscopic observations were made through optical and scanning electron microscopes and X-ray analysis was also conducted. The temperature and deformation rate had great influence on microstructure and fracture type of hot rolled alloy. The hardness increased with increasing deformation rate and temperature.

Keywords : deformation rate, microstructure, X-ray analysis, hot rolling

Fabrication and wear behavior of palm ash/phenolic based composite
Mohd Radzi Ali, Shamsul Baharin Jamaludin, A.Z. NurHidayah
Pusat Pengajian Kejuruteraan Bahan
Universiti Malaysia Perlis
Jejawa 2, Taman Muhibah
02600 Arau
Perlis
Malaysia

Abstract

A large quantity of palm ash by product is produced every year in Malaysia and only small quantities of palm ash are currently utilized. This paper has focused on the future potential application of palm ash as filler material to develop new composition of brake pad. The composite samples for brake pad application were developed by pre-mix the palm ash, CaCO₃, phenolic resins, Al₂O₃, graphite and steel fiber mill and then compacted at a pressure of 15MPa. All samples were cured at 150°C for 5 minutes. Wear loss of the composites samples was studied by using the modified MetkonGropo V1 grinder-polisher. SEM and stereomicroscope were used to analyze the morphology of worn surface.

Keywords : Wear, palm ash, CaO₃, phenolic resins, Al2O3, graphite and steel fiber

Synthesis and Characterization of Mixed Oxide based Molybdenum Catalysts
Muhammad Farooqa¹, Anita Ramli¹, Duvvuri Subbarao^2
1Department of Chemical Engineering
¹Fundamental and Applied Sciences Department
Universiti Teknologi PETRONAS,
Bandar Seri Iskandar,
31750 Tronoh, Perak, MALAYSIA

Abstract

Mo catalysts supported on gamma alumina and alumina-magnesia mixed oxide by varying the MgO contents were prepared by wet impregnation method. The textural properties of these synthesized Mo catalysts were explored by various analytical techniques such as N₂ adsorption–desorption (BET), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray fluorescence spectrum (XRF), Temperature-programmed reduction (TPR), Transmission Electron Microscopy (TEM). The results showed that the addition of MgO contents affected the binding energies of various elements and reducibility of the metal oxides formed after calcination of catalyst samples due to different metal-support interaction. Moreover, the characterization techniques showed that the active metal distributed uniformly on the surface of support material due to interaction with support.

Keywords : Mixed oxides based catalyst, Synthesis, Characterization and Binding energy.

Facile Preparation of Metal Oxide Decorated Reduced Graphene Oxide Nanocomposite
Huang Nay Ming

Low Dimensional Materials Research Centre,
Block A, Physics Building,
University of Malaya,
50603 Kuala Lumpur, Malaysia

Abstract

A facile approach has been introduced on synthesis of Reduced Graphene Oxide-Titanium Dioxide (RGO/TiO₂) nanocomposites. Titanium Oxide nanoparticles formed concurrently on the Reduced Graphene Oxide (RGO) with the reduction process of Graphene Oxide (GO) to Graphene by the hydrothermal approach. Triethanolamine (TEA) plays the major role of both co-reducing agent as well as capping agent to form a well-dispersed TiO₂ sol. Narrow size distribution of Titanium Dioxide nanoparticles (~20 nm) are achieved and uniformly distributed on the Reduced Graphene Oxide nanosheet. The approach is simple with only single-step of hydrothermal and tedious calcinations and annealing steps associated in conventional method are eliminated. Furthermore, the TGA analysis showed enhanced thermal stability for the nanocomposites. In addition, RGO/TiO₂ nanocomposites modified glassy carbon electrode (GCE) displayed excellent enhancement of electrochemical performance over the conventional GCE in interacting with mercury (II) ions in potassium chloride electrolyte.

Keywords : graphene oxide, hydrothermal, nanocomposite

Polysilicon Nanogap Mask Design fabrication using Photolithography Technique 
Q. Humayun, U. Hashim, M.N.B. Derman, Tijjani Adam
Institute of Nano Electronic Engineering Universiti Of Malaysia Perlis (UniMap)
Lot 106,108,and 110 Blok.Seriab ,Kangar, Perlis.

Abstract

To fabricate Nanogap using photolithography technique, alignment and exposure are the most critical steps. Each mask should be precisely aligned with respect to the original alignment mark. So that the original pattern transfers successfully to the wafer surface while unsuccessful pattern will cause device and circuit failure. Precise transfer of pattern means guarantee in high repeatability and reliability, high throughput and low cost of ownership. By improving this resolution and alignment precision the minimum size can be further reduced to 1nm and beyond and other important aspect of achieving minimum precised size is, the photo resist must be very sensitive to the exposure light to achieve reasonable throughput. However, if the sensitivity is too high, other photoresist characteristics can be affected, including the resolution. In this study, we have designed 2 masks for the fabrication of polysilicon Nanogap during pattern transfer process steps, each one was precisely aligned with the previous to achieve successful pattern transfer in the fabrication. There was a very little room for alignment error, we were able to achieved exact dimension of the critical dimension during pattern transfer.

Keywords : Keywords: Photolithography, Pattern transfer, Nanogap, repeatability and reliability, fabrication, precision, alignment, critical dimension.

THE SEM MICROSTRUCTURE AND THERMOLUMINESCENT STUDY OF IRRADIATED LEAD SILICATE GLASSES
Nor Hayati Alias, Nurazila Mat Zali, Azali Muhammad, Wan Saffiey Wan Abdullah and Nurhaslinda Ee Abdullah
Malaysian Nuclear Agency Bangi
43000 Kajang, Selangor, Malaysia

Abstract

The SEM (Scanning Electron Microscopy) microstructure and Thermoluminescent(TL) study of several lead silicate glasses containing 30-70 mol% of PbO have been studied after being irradiated by Co60 at dose rate 150rads^-1. Analysis has been carried out as to observe the glass microphase separation. It is occured that irradiation on glasses may alter its properties determined by microstructural variations in composition.

Keywords : lead silicate glass, microstructure, thermoluminescent

Finite element Method Micro channel Simulation for Nano-Lab-on-chip
 Q. Humayun, U. Hashim, M.N.B. Derman, Tijjani Adam
Institute of Nano Electronic Engineering Universiti Of Malaysia Perlis (UniMap)
Lot 106,108,and 110 Blok.Seriab ,Kangar, Perlis.

Abstract

For the delivery of bio-logical species to the surface of biosensor the most important task to design a high sensitive and reliable Microfldics. The sensing fluidics experiments are accomplished in either open or closed ceroscopy chambers. Although, the integration of Microfluidics module on a chip can offer several advantages including, ability to analyze small volumes of sample with or without small solvents and minimize costly reagents consumption, short reaction times, automate sample preparation, portability and ease of integration with other miniaturized devices. But it is still fraught with challenges. These challenges include developing highly sensitive and selective low-cost fluidic Nano Lab-On-Chip used for Medical Diagnostic System. The detection of cancer bio-molecule at early stage is an active area of current research. In this paper we studied fluid flow by capillary action within micro channel, we used finite element method and established a sufficiently possible minimum gab between two parallel plate utilized the principle of cohesive and adhesive to create smooth fluid flow in the microfluidic channel without acquiring any external force using (COMSOL) Multiphysics software.

Keywords : Microfluidics, Lab-on-chip, Micro channel, biosensor, COMSOL.

TEMPERATURE MANIPULATION FOR CARBON NANOTUBES GROWTH BY USING CHEMICAL VAPOR DEPOSITION (CVD)
M.Asyraf.B.A.Z ,A.Azniza , M.Nuzaihan.M.N, and W.M.W.N.Haimi
Institute of Nano Electronic Engineering,
University Malaysia Perlis (UniMAP)
Lot 106, 108, & 110, Tingkat 1 Block A, Taman Pertiwi Indah,
Jalan Kangar-Alor Setar, Seriab, 01000 Kangar, Perlis, Malaysia

Abstract

Nanotechnology deals with the creation of useful, functional materials, devices and system by controlling or manipulating matter at the nanoscale. Carbon nanotube or CNTs is a tube-shaped material, made of carbon that having a diameter measuring on the nanometer scale. Carbon nanotubes appear in many structures, differing in length, thickness and in the type of helicity and number of layers. The electrical characteristic for CNTs is differing depending on these variations and its can acts as metals or semiconductor. In this research we will focus on temperature manipulation for CNTs by using Chemical Vapor Deposition (CVD) technique. The goal for this research is to growth CNTs below 100nm by changing the growth temperature. Variations of these temperatures will give a different growth for CNTs, for this research temperature variation we are using is 750 C, 650 C, 550 C and 450 C. SEM and EDX will used in this research for CNTs analysis to observe morphology and CNTs diameter growth.

Keywords : Carbon Nanotubes (CNTs), Chemical Vapor Deposition (CVD), SEM , EDX

The effect of solution treatment temperature on the microstructure development of precipitates in A319 alloy
Murizam Darus, Shamsul Baharin Jamaludin
School of Materials Engineering,
Universiti Malaysia Perlis
Kompleks Pusat Pengajian Jejawi 2,
01000, Kangar Perlis, Malaysia.

Abstract

Precipitation occurrence during artificial ageing process plays a vital role in A319 alloy strengthening mechanism. Samples of A319 alloy were subjected to various artificial ageing conditions. Two set of samples were solution treated at 510°C and 525°C, then followed by artificial ageing at 180°C. The over-aged samples from each solution treatment temperature condition were then observed under scanning electron microscope. It was found that the Al2Cu precipitate occurs in both solution treatment conditions, while the Mg2Si precipitates was only appeared in higher solution treatment temperature.

Keywords : A319 alloy, solution treatment, artificial ageing, scanning electron microscope

THE EFFECT OF DELIGNIFICATION ON PAPER PROPERTIES OF ACETOSOLV OIL PALM FROND FIBERS PULP
Nasrullah RCL^1,2 ,W.D. Wan Rosli 1 and I.Mazlan 1
¹Division of Bioresource, Paper and Coatings Technology
School of Industrial Technology, University Sains Malaysia 11800 Penang, Malaysi
²Department of Chemical Engineering Syiah Kuala
University Banda Aceh Indonesia

Abstract

Delignification of oil palm frond fiberes was conducted in a 4 –litre laboaratory digester in order to investigate its influence on the properties made from unbleached acetosolv pulps. The results indicate that the tensile and burst indices increased with increasing degree of delignification, whereas tear index showed an opposite effect. Brightness also increased as a result of delignification.

Keywords : Acetosolv pulping, Oil Palm frond fibres, , delignification , brighness

The Effects of Lipopolysaccharides on the Ultrastructure of Sea Cucumber
Noor Hidayu P.1, Nik Norliza N.H.1, Mohsin S.S.J. 2
1School of Health Sciences, Health Campus, Universiti Sains Malaysia,
16150 Kubang Kerian, Kelantan, Malaysia.
2Biomedical & Health Sciences Research Platform,
Health Campus, Universiti Sains Malaysia,
16150 Kubang Kerian, Kelantan, Malaysia.

Abstract

The objective of this study was to investigate the effects of foreign material, in this study lipopolysaccharide (LPS) on the ultrastructure of four species of sea cucumber, Stichopus horrens, Stichopus vastus, Stichopus variegates and Holothuria edulis. The experiment was divided into two groups, control and challenged group. Control group was not injected with LPS while the challenged group was injected with LPS. The animals were dissected and the tissue specimens were collected and stored at -20°C until it is further processed for transmission electron microscopy (TEM) viewing. Ultrastructural examination by using Hitachi H-7100 transmission electron microscope showed that the tissue structure between control and challenged group were different. The changes in the ultrastructure of sea cucumber were also different from each other. This study suggested that LPS may cause the sea cucumber to react in certain ways to expel the foreign materials outside its body hence causing the changes in the tissue structure.

Keywords : LPS, TEM,ultrastructure

Histopathologic Features of Xenografted Tumour Model of SW 1271 Small-Cell Lung Carcinoma Cell Line in Athymic Nude Mice
Abubakar Danjuma Abdullahi^1,2, Sanda Aung¹, Abdul Razak Kasmuri¹, Nadia Hanis Binti Abdul Samat¹, Nur’ Izzati Binti Mansor¹,Roslan Harun ^2
1Kulliyyah of Pharmacy, International Islamic University Malaysia
²Medical Molecular Biology Institute, University Kebangsaan Malaysia

Abstract

Small-cell lung cancer is associated with very poor prognosis due to its rapid doubling time and early metastatic behaviour. Though development of xenograft tumour model is essential for preclinical testing of new therapeutic agents and genes function studies, characterizing these models is crucial in determining how xenografted cell line grow and interact in mouse micro-environment and how this interaction affects its growth and morphology. SW 1271 is a cell line that has been widely used as an in vitro model. But there is paucity of data on its use as small-cell lung cancer xenograft tumour model. In this study, we transplanted 20 million SW 1271 into athymic nude mice and studied the pattern of in vivo tumour growth and pathology. The results of H and E stained histopathology slides show solid pattern of tumour cells with pinkish cytoplasm, presence of both hyperchromatic and vesicular nuclei, presence of numerous giant cells and scattered mitotic features. There was increase in the nuclear cytoplasmic ratio but no clear cell membrane between adjacent cells. The result provides a new xenograft model of small-cell lung cancer for preclinical studies.

Keywords : Xenografted tumour model, SW 1271 Small-Cell Lung Carcinoma Cell Line, histopathologic features

IN SITU SYNTHESIS OF CHITOSAN/ HYDROXYAPATITE COMPOSITE: EFFECT OF CHITOSAN CONCENTRATION I. Zainol¹,*, M.Z.A.Azraie¹, H.M.Z Haniza2, C.N. Aiza Jaafar^3
1Chemistry Department, Faculty of Science and Mathematics, Universiti Pendidikan Sultan Idris,
35900 Tanjong Malim, Perak, Malaysia.
²Biology Department, Faculty of Science and Mathematics, Universiti Pendidikan Sultan Idris,
35900 Tanjong Malim, Perak, Malaysia.
³School of Materials and Mineral Resources Engineering, Engineering Campus,
University Sains Malaysia, 14300 Nibong Tebal, Seberang Perai, Malaysia.

Abstract

The aim of this project is to study the effect of chitosan concentration in in-situ synthesis of chitosan/hydroxyapatite (CS/HAp) composites. The chitosan/H3PO4 solution was prepared by varying the concentration of chitosan content from 0.2 to 2.2 % (w/v). The chitosan/H3PO4 solution was dropped into Ca(NO₃)₂.₄H₂O to precipitate HAp in the chitosan matrix. Fourier transforms infrared (FTIR) confirmed the presence of HAp in the composites by the present of strong absorption band at 1037 and 566 cm-1 which was corresponding to PO4-3 functional groups. The percentage of chitosan in the CS/HAp composite was determined using thermogaravimetry analysis (TGA) whereas XRD was used to record the presence of crystalline peak due to HA phases in the composites. The TGA results show that the HAp content varied from 56 to 78 % (w/w) in the CS/HAp composites. The CS/HAp composite sample shrunk about 8.5 to 62 % from its original volume when heated from room temperature to 1000^oC. The results of XRD analysis showed the presence of crystalline peak due to HA phases in the composites. HA particles were found to be well distributed in the chitosan matrix as shown by scanning electron microscope (SEM) analysis results.

Keywords : chitosan/hydroxyapatite composites, in-situ precipitation

ZnO nano-stripes synthesized using photoelectrochemical wet etching method
L.S. Chuah^1*, Asmiet Ramizy², M. A. Mahdi², Z. Hassan², S. K. Mohd Bakhori^2
1Physics Section, School of Distance Education, Universiti Sains Malaysia,
²School of Physics, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.

Abstract

To date, no approaches have been reported to fabricate the ZnO nano-stripes arrays on zinc foil substrate. In this method, zinc (Zn) foil was applied as substrates. The ZnO nano-stripes arrays on zinc foil substrate were prepared via photoelectrochemical (PEC) wet etching method without using templates and catalysts. To prepare ZnO nano-stripes structures, the samples were dipped into a mixture of H2NO3:Ethanol (1:5) with current densities of 127 mA/cm2, and subjected to external illumination from a 100W lamp. The constant etch time is 30 min. After etching, the surface morphology and the nano-stripes structure of the ZnO films were characterized by scanning electron microscope (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction (XRD). XRD pattern confirmed that the hexagonal wurtzite structure of ZnO nano-stripes were of polycrystalline structure. The optical properties of the ZnO nano-stripes arrays were characterized by Raman and photoluminescence spectroscopies at room temperature (RT). Micro-Raman results showed that A1(LO) of hexagonal ZnO nano-stripes have been observed at 520 cm-1. PL spectrum peak is obvious at 368 cm-1 for ZnO film grown on zinc foil substrate. The PL spectrum peak position in ZnO nano-stripe is blue-shifted with respect to that in unstrained ZnO bulk (381nm). This can be clarified by the approximately smaller statistical area spreading of the nano-stripes. Nano-stripes ZnO can be used as a buffer or intermediate layer to lessen substrate-induced strain, similar to porous siliconn.

Keywords : nano-stripes, ZnO, PEC, SEM, XRD, Raman, PL.

CELLULOSE ACETATE PRODUCTION OF ALKALINE PEROXIDE PULP FROM OIL PALM EMPTY FRUIT BUNCH VIA TCF BLEACHING TECHNIQUE 
Nurul Hasanah Kamaludin, Arniza Ghazali, Wan Rosli Wan Daud, Leh Cheu Peng and Yunita Megasari Dermawan
School of Industrial Technology, Universiti Sains Malaysia,
11800 USM, Penang, Malaysia
Corresponding author: Tel: +604-6532239, Fax: +604-6573678
E-mail: arniza@usm.my

Abstract

This study revealed suitability of EFB as raw material in the possibility of deriving cellulose acetate (CA). This lignocellulosic material was subjected to Alkaline Peroxide Pulping (APP) prior to CA production. The resulting pulp was bright (65-70% ISO) and found to be of high purity upon subjecting to totally chlorine-free bleaching (TCF) in order to remove the residual of non-cellulosic materials. Bleaching stages begins with oxygen bleaching, followed by ozone bleaching and peroxide bleaching (OZP), sequentially. CA films produced in this experiment were analyzed using Scanned Electron Micrograph (SEM). The smoothest surface was presented by OZPCA, as evidence of very high purity of cellulose acetate. This was also proved by differential scanning calorimetry (DSC) of the produced cellulose acetate, which performed even better thermal characteristics compare to commercial CA. The successful conversion of the alkaline peroxide pulp from EFB, to cellulose acetate by acetylation and subsequent TCF bleaching process offered cellulose acetate comparable to commercial cellulose acetates.

F bleaching.

Keywords : alkaline peroxide pulping, cellulose acetate, EFB, SEM, TC

Effect of Polyethylenimine Loading on the Physicochemical Properties of Amine-Functionalized Si-MCM-41
Sohail Ahmed¹, Anita Ramli² and Suzana Yusup^1
1Department of Chemical Engineering,
²Department of Fundamental and Applied Sciences
University Technology PETRONAS,
Bandar Seri Iskandar, 31750, Tronoh, Perak, Malaysia

Abstract

Si-MCM-41 with highly ordered uniform hexagonal mesopores was synthesized hydrothermally at 100 ^oC. The calcined Si-MCM-41 was then functionalized with 10-50% (w/w) polyethylenimine (PEI) via impregnation method. The physicochemical properties of these samples were characterized using FTIR, TGA, FESEM, TEM and CHNS analysis. Results show that the Si-MCM-41 was successfully functionalized with PEI. FTIR analysis shows that all the characteristic peaks of Si-MCM-41 are still present in PEI-functionalized Si-MCM-41, which means that the mesoporous frame work is preserved. TGA analysis shows that the PEI-functionalized Si-MCM-41 is thermally stable up to 200-250 ^oC. FESEM images show that as the PEI weight percent increases to 50w%, the PEI-functionalized Si-MCM-41 became agglomerated, which indicates that the PEI is distributed into the pores and on the surface of the Si-MCM-41. TEM results also show that the hexagonal pore structure remains intact and the pores are filled with PEI. CHNS analysis confirms the presence of nitrogen in the PEI-functionalized Si-MCM-41.

Keywords : Si-MCM-41, mesopores, functionalization, Polyethylenimine, impregnation method