bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, CO2 Adsorption Performance of Modified MIL-101 with Multi-Wall Carbon Nanotubes
Authors: Ullah Sami , Bustam Mohamad Azmi , Elkhalifah Ali E.I. , Riaz Nadia , Gonfa Girma , Shariff Azmi Mohamad
Published: December 2015

Nearly 40% of the world gas reservoir contains high level of CO2 that stance problems to development. The discovery of natural gas field with CO2 content of as high as 87% in Malaysia poses new challenges in terms of the CO2 separation processes. This research work investigates the potential of MIL(Materials Institute Lavoisier)-101 as CO2 capture and storage candidate by conducting an experiment with different pressure between the synthesised and modified MIL-101 using Multi-wall carbon nano tubes (MWCNTs). To investigate the effect of the MWCNTs in MIL-101 towards CO2 adsorption performance. The synthesized MOFs were characterized using scanning electron microscopy (SEM) for surface morphology, Thermogravimetric analysis (TGA) for thermal stability, X-ray diffraction (XRD) for crystals plane, Brunauer-Emmet-Teller (BET) for surface area and CO2 adsorption performance. The result had showed that the modified MIL-101 enhanced the CO2 adsorption compared to the pure MIL-101. MWCNT@MIL-101 showed the adsorption of CO2 uptake is 0.0029mmole-1/g at 100kPa.
Effect of Colloidal Nano Silica as a Viscosity Modifying Agent in Self Compacting Concrete with High Volume POFA
Authors: Kojouri Samira Jilani , Abang Ali Abang Abdullah , Farzadnia Nima
Published: December 2015

This paper presents effects of Colloidal Nano Silica (CNS) as a Viscous Modifying Agent (VMA) on fresh properties of self-compacting concrete (SCC) containing high volume ground Palm Oil Fuel Ash (POFA). Accordingly, fresh properties of the SCC were tested using slump flow, J ring, L-box, and sieve stability test. To monitor the viscous behaviour of the fresh SCC with CNS, fillingability and passingability parameters were maintained within a desirable performance criterion whilst segregation, cohesiveness, and superplasticizer demand were the variables. All the mixtures were designed with the water/binder ratio of 0.45 and a total binder content of 500 kg/m3. The results revealed that the inclusion of CNS decreased the segregation and augmented the cohesion in all mixes.
Phase Transformation of Biphasic Granules of Gypsum and Carbonated Apatite at Low Temperatures
Authors: Mohd Sabri Siti Noorzidah , Abu Bakar Syazana , Abdul Manaf Abdul Yazid , Hisham Siti Farhana , Ahmad Mohamad Azmirruddin , Thevi K. Jamuna , Noorsal Kartini , Shariff Khairul Anuar , Ishikawa Kunio
Published: December 2015

The purpose of this study was to prepare biphasic granules containing gypsum and carbonated apatite at low temperatures. The biphasic granules were prepared using dissolution-precipitation technique at three different temperatures 30°C, 40°C and 50°C. Characterization of the biphasic granules was determined by multiple analytical methods such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infra-red (FTIR), and CHN Analysis. The obtained granules were determined by XRD as biphasic granules containing bone apatite and gypsum. The cross-section of biphasic granules was observed by SEM. The formed bone apatite was identified as B-Type carbonated apatite using FTIR The carbonate content in biphasic granules fabricated at 30°C, 40°C and 50°C were recorded by CHN analysis as 5.0 wt%, 6.1 wt% and 6.25 wt%, respectively.
Synthesis and Characterization of Single-Layer TiO2 Nanotubes
Authors: Zulfiqar Muhammad , Omar Abdul Aziz , Chowdhury Sujan
Published: December 2015

In this paper, TiO2 nanotubes (TNTs) were synthesized through simple chemical hydrothermal treatment process when anatase TiO2 nanopowder is chemically treated with 10 M NaOH and >99.5% ethanol at 180°C for 24 hr. According to the transmission electron microscopic (TEM) image analysis TNTs tubes were formed in the length sizes from 400 to 700 nm with inner diameter of 5 nm and outer diameter of 8 nm. The morphological and structural properties of synthesized TNTs was characterized by powder X-ray diffraction (XRD), thermal gravimetric analysis (TGA), UV–Vis diffuse reflectance spectra (DRS).
Morphology and Structural Characteristic of Nanocrystalline Cellulose (NCC) Hydrolyzed from Filter Paper
Authors: Asari @ Mansor Nuruzatulifah , Kasa Siti Norbaya , Nizam Ismarul , Ahmad Termizi Afifah Hanim
Published: December 2015

The aim of this study was to study the morphology and structural characteristic of NCC hydrolyzed from filter paper. The NCCs were extracted by acid hydrolysis at 50°C for 1 hour, using 55% conc. H2SO4 under vigorous mechanical stirring, centrifugation at 12000 rpm in distillate water and followed by homogenizing at 7000 rpm. The morphology and surface profiles of the NCC suspension was characterized using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM). The crystalline structure of the NCC was evaluated by using X-ray diffraction (XRD) technique. As a result, hydrolysed NCC was found to have a rod liked shape with diameter in the range of 100-300nm length and 10-50nm width, with the aspect ratio value of 10.3 nm. According to XRD investigations, the semi-crystalline cellulose was observed with the presence of an amorphous broad hump and crystalline peaks at 2θ of 15o and 22.7o, respectively. The crystalinity index of the raw filter paper was calculated as 86.7 % and increased to 94.4 % as it was extracted to NCC. Crystallite size of raw filter paper and NCC was calculated as 20.6 nm and 11.4 nm, respectively
Structural and Field Electron Emission Properties of Pure and Al-Doped ZnO Nanorods Prepared by Sol-Gel Method
Authors: Rafaie Hartini Ahmad , Md Nor Roslan , Mohd Amin Yusoff
Published: December 2015

The structural and field electeron emission properties of pure and Al doped ZnO nanorods synthesized on the Al substrates using sol-gel method has been studied. Al doping at different levels was achieved by adding Al2NO3 at 1, 3 and 5 Al at. % with respect to Zn in the synthesis solution. X-ray analysis shows that all the obtained ZnO nanorods can be indexed to the hexagonal ZnO wurtzite structure. Field electron emission measurement using the nanorods as cathode gave a trend of decreasing turn-on field values with increasing Al-doping levels, with values of 7.2 V/μm, 6.6 V/μm, 6.0 V/μm and 5.8V/μm for pure ZnO nanorods, 1, 3 and 5 at% Al-doped ZnO nanorods, respectively. The F-N plot has a linear relationship and the field enhancement factor for all samples has been obtained.
Synthesis and Characterization of Fe2O3/TiO2/ SiO2 and Fe2O3/TiO2/Activated Carbon Nanocomposite Photocatalysts for Dye Removal
Authors: Ahmad Zubir Zuhana , Ibrahim Suhaina Mohd , Muhammad Nor Adhila , Ahmad Mohamad Ibrahim , Yeoh Fei Yee , Lee Ting , Shaari Nur Shuhada
Published: December 2015

Magnetic nanocomposite photocatalyst is an alternative approach for easy separation of catalyst from the treated water by magnetic force. This paper will discuss the performance of dye degradation using two different supported layer; Silica and Activated Carbon that shield between magnetic iron oxide (Fe2O3) and Titanium dioxide (TiO2) photocatalyst. Photocatalytic activity is measure using Methylene Blue (MB) as indicator. The magnetic nanocomposite was synthesis using an evaporation indused self-assembly (EISA) approach and wet synthesis method. The photocatalyst were then characterized using Vibrating Sample Magnetometer (VSM), Brunauer-Emmet-Teller (BET), and Transmission Electron Microscope (TEM) and the effect of dye degradation were characterizing using Ultraviolet-Visible (UV-VIS) spectroscopy. The result showed that activated carbon is the good supporter compare to silica.
The Effects of Oil Palm Empty Fruit Bunch Sorbent Sizes on Plumbum (II) Ion Sorption
Authors: Daneshfozoun Safoura , Abdullah Bawadi , Abdullah M. Azmuddin
Published: December 2015

Oil Palm Empty Fruit Bunch (OPEFB) contributes more than 50% of oil palm biomass wastes in Malaysia. This provides tremendous opportunities for value-added product generation from recycling and utilizing its latent capacity. In this work, the performance of physically-pretreated OPEFB fibers without any chemical treatment for Pb2+ removal from aqueous system was evaluated. Three different size ranges (1-5 cm, 0.5-2 mm and 0.005-0.02 mm) of raw sorbent, pH (4-10) and contact time (2-150 min) for Pb2+ batch adsorption were tested. The kinetic data were evaluated by the pseudo-first-order, pseudo-second-order and intra-particle diffusion model. The experimental data were well described by the pseudo-second-order model with r2=0.997. Adsorption efficiency was size-dependent with about 38% sorption increase at 0.005-0.02 mm, and reached 94% efficiency, achieved 47.49 mg/g capacity with 500 ppm Pb2+ at pH 7.5, in 60 min. The eco-friendly, low cost sorbent can be applied as green, effective adsorbent in waste water remediation.
Effects of Pressure and Temperature on the Dissolution of Cellulose in Ionic Liquids
Authors: Moniruzzaman Muhammad , Mahmood Hamayoun , Ibrahim Mohamed Farouk , Yusup Suzana , Uemura Yoshimitsu
Published: December 2015

Cellulose –Earth’s most abundant biopolymer–represent an enormous carbon-neutral renewable resource of biomaterials and bioenergy. The dissolution of cellulose with environmentally friendly and efficient solvents/methods is an important and challenging for further chemical processing. In recent years, room temperature ionic liquids (ILs)- a attractive “green” and “designer” solvent-have emerged as a potentially attractive “green” solvent for dissolution of cellulose for further processing. In general, dissolution of cellulose in ILs via conventional heating system requires high temperature and long pretreatment time. This study reports the effect of pressure on the dissolution of cellulose in IL [C2mim][OAc] (1-ethyl-3-methylimidazolium acetate). The effects of temperature and pressure on cellulose dissolution time were investigated using high Pressure Solubility Measurement System (HPSMS). It was found that as the pressure and temperature increased, the dissolution time decreased significantly. For comparison, the original microcrystalline cellulose (MCC) and regenerated cellulose from ILs after dissolution were characterized using scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The results clearly revealed that the thermal stability of regenerated cellulose were reduced.
Failure Criteria and its Application in Wellbore Studies
Authors: Irawan Sonny , Bataee Mahmood , Zare Mohammad Reza
Published: December 2015

This paper has reviewed the failure criteria that had been applied in the wellbore studies. Rock failure studies had applied in the wellbore and reservoir to establish the stability, which is a major problem in oil and gas wells. There problems are both in injection wells and production wells. In injection wells, fracturing is a problem and in production wells, sand production affects the oil flow rate. The stress state of the well determines the stability of the well using the failure criteria.Different failure criteria and their applications had been studied. The theory of the failure has expressed; then applied criteria, formulation and modification of different criteria is expressed for different wellbore studies. And finally the important aspects and differences in wellbore failure rather than the rock surface failure has been discussed.
Volumetric Properties of Alkali Salt in Aqueous 1-Butyl-3-Methylimidazolium Tetrafluoroborate at Various Temperatures
Authors: Lal Bhajan , Keong Lau Kok , Bustam Mohd Azmi , Sufian Suriati , Murugesan Thanabalan
Published: December 2015

Volumetric characterstics of multiple electrolytic solutions in a wide range of solute concentrations and solutions temperatutre are of fundamental importance for the understanding of numerous physicochemical processes occurring in various brances of the chemical industry as well as in the natural envirnoment. In a view of importance of NaCl as primary salts in seawater and most of other natural water, accurate thermophysical data is crucial for understanding industrial and natural processes [1]. Ionic interaction plays an important role in chemical reactions in solutions [2]. In fact, the effect of the addition of salts in aquous solutions of ILs is very complex, primarily because a large number of different types of intermolecular interactions come into play between the ion and water, ion and IL, and IL and water. From a thermodynamic perspective, the solvation of ionic species in the ILs is much more favored than in conventional solvents. This is one of the key advantages of using ILs in separations involving ionic species.
Microporous Chitosan-Succinonitrile Membrane for Lithium Rechargeable Batteries
Authors: Taib Nur Umira , Idris Nurul Hayati
Published: December 2015

In this work, microporous chitosan-succinonitrile membranes were prepared by phase separation method. The membranes were characterized using electrochemical impedance spectroscopy and scanning electron microscope. It was found that the addition of succinonitrile increased the pore size, which in turn increased the ionic conductivity of the chitosan-succinonitrile membrane.
Effects of Binder and Processing Parameters on Processability of Porous Ti/HA Composite through Powder Injection Molding
Authors: Rafi Raza Muhammad , Bakar Sulong Abu , Muhammad Norhamidi , Niaz Akhtar Majid , Rajabi Javad
Published: December 2015

Powder injection molding (PIM) process is suitable for both metal and ceramic materials to produce parts with high volume and accuracy at low cost. In this research work, 90wt. % of Ti6Al4V was dry mixed with 10wt. % of Hydroxyapatite (HA). The resultant mixture was further mixed with different space holders in weight ratio 8:2. The feedstock was prepared by mixing the final mixed powder with PEG and PW based binder systems. The dumbbell shape parts were produced using DSM Xplore injection molding machine. The molded samples were debound into two stages i.e solvent extraction followed by thermal debinding. The debinding parameters were optimized for different binder with space holders. The major binders’ paraffin wax (PW) extracted in haptane and PEG in water immersion at temperatures of 60 °C and 50 °C for 5 hrs respectively. The thermal de-binding was performed successfully at 500 °C by varying the heating rate from 3 °C/min-5 °C/min with holding time 1hr in argon atmosphere followed by the sintering in vacuum. During molding short shot defects and cracks were observed while during debinding, collection of binder, swelling and holes were noted. These types of defects may be due to space holder, improper binder, heating rate, temperature and dwell time at each processing step. The sintered test specimens were analyzed for porosity and microstructure. The results showed that the PEG based binder system with NaCl space holder is more effective to produce porous Ti/HA composite through PIM. Porous Ti/HA composite showed interconnected pores with average size of 90µm.
Mechanical Properties of Cr/CrN/CrCN/ZrN Multilayer Coatings by Physical Vapour Deposition (PVD)
Authors: bin Abdullah Mohd Zakuan , bin Abdullah Ahmad Nizam , bin Othman Mohamad Hazri , bin Morat Amin , bin Ahmad Mohamad Azmiruddin
Published: December 2015

Multilayer coating onto orthopedic implants has been studied extensively due to their excellence mechanical and biological properties. A multilayer coating was coated onto metal implants to prevent the leaching of metallic ions into human body. This paper aims to study the hardness of multilayer coatings of Chromium (Cr), Chromium Nitride (CrN), Chromium Carbonitride (CrCN) and Zirconium Nitride (ZrN) by Physical Vapour Deposition (PVD). The deposited multilayer coating was characterised by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD) and Energy Dispersive X-ray (EDX). Cr, CrN, CrCN and ZrN have been successfully deposited onto stainless steel substrates by PVD. XRD analysis detected major peak in preferred orientation of (200) and other peaks with (111), (220), (311) for CrN cubic phase. For CrCN, XRD analysis detected only low intensity peaks of Cr7C3 and ZrN peaks with preferred orientation of (111), (200) with other peak (220), (311) and (222). Microvickers Hardness results showed an increment in hardness value from substrates with 160HV to 174HV for Cr, 236HV for CrN, 362HV for CrCN, 364HV for ZrN and 370HV for multilayer coatings.
Effect of Ozone Treatment on Properties of Screw Pressed and Non-Screw Pressed Empty Fruit Bunch Medium Density Particleboard
Authors: Ali Roslan , Mohammad Taib Mohamad Nurul Azman , Wok Kamal , Tahiruddin Shawaluddin , Abdullah Mohd Amrin
Published: December 2015

This study was done to investigate the effects of ozone treatment as a method to improve the properties of empty fruit bunch (EFB) medium density particleboard. Two types of EFB were used in this study i.e. screw pressed and non-screw pressed empty fruit bunch. These EFB were treated in an ozone chamber for 8 hours prior to particleboard manufacturing. The mechanical properties, Modulus of Elasticity (MOE), Modulus of Rupture (MOR) and Internal Bonding (IB) and physical properties, water Absorption (WA) and Thickness Swelling (TS) of EFB particleboard were determined. The results showed that the ozone treatment could increase the MOR and IB values of EFB particleboard, but had no significant effect on MOE values. For physical properties, the values showed no improvement for TS and WA. The panels manufactured using ozone treatment was found suitable for applications for furniture products.
Chemical and Thermal Analysis of Silk and Silk-Like Fibres
Authors: Kamarun Dzaraini , Omar Khadijah , Yusof Farida Zuraina
Published: December 2015

Natural silk and silk-like synthetic fibres share common external features and ‘hand’ characteristics which cause confusion to end users. Standard chemical tests are the best known technique available but not the most desirable due to the use of chemicals. An alternative technique, thermogravimmetric analysis using a thermogravimmetric analyzer (TGA) is as reliable and is more environmental-friendly. Several fabric samples of natural (silk) and synthetic origin were tested for comparison using the two techniques: TGA and a standard chemical procedure. Bivoltaine and multivoltaine cocoons were used as standards. It was found that all fabric samples tested using TGA agreed with the results obtained from chemical analysis implying the potential of using TGA as an alternative technique to the wet chemical method.
Modelling of Steel Fibre Reinforced Concrete Ribbed Slab under Multiple Ribbed Condition
Authors: Samsudin Amir Syafiq , Mohd Hashim Mohd Hisbany , Hamzah Siti Hawa , Abu Bakar Afidah , Mohamad Mohamad Firdaus
Published: December 2015

Nowadays, demands in the application of fiber in concrete increase gradually as an engineering material. Rapid cost increment of material causes the increase in demand of new technology that provides safe, efficient and economical design for the present and future application. The introduction of ribbed slab reduces the material and thus the cost but the strength of the structure also reduce due to the reducing material. This paper will focus on modelling behavior of ribbed slab reinforced with steel fibre using Lusas Modeller. The structure design is in full aspect to optimize the function of steel fibre and the slab rib capability. This research focus on modelling of multiple type of steel fibre ribbed slab consist of two ribbed slab, and also three ribbed slab in similar size of 1500mm x 1000mm x 75mm using concrete Grade 30. Load was applied until failure under three point loading system. It is importance to find the ultimate strength of the sample and the behavior of structure under vertical stress. Steel fibre is expected to reduce the issue of micro crack and enhance the performance of concrete.
Effect of Carbon Black Structures towards Heat Build-Up Measurements and its Dynamic Properties
Authors: Rifdi Rizuan Mohd Ismail , Abdul Wahab Mohammad Azizol , Romli Ahmad Zafir
Published: December 2015

The aim of this study is to investigate the effect of different carbon black structures towards heat build-up measurements and its dynamic properties such as tangent delta, loss modulus and storage modulus on the industrial rubber compounds containing Natural Rubber (NR) and Styrene Butadiene Rubber (SBR). Different carbon black structures were used and characterised with respect to their rheological and physical properties. Heat Build-up test is a testing procedure which is used to measure the rate of heat generated by the rubber vulcanisates when subjected to rapidly oscillating compressive stresses or strain under controlled conditions. It was found that NR compound containing low and high carbon black structures; N375 and N339 produced lower heat generation compared to NR/SBR blends that filled with the same type of carbon black fillers. It shows that NR with low and high carbon black structures exhibits low heat build-up (surface and intrinsic) with a balance of good traction and low rolling resistance for application in tyre.
Bending Strength of Finger Jointed Kelat Wood (Syzygium spp.) as Affected by Finger Length and Orientation
Authors: Abdul Hamid Nur Hasmiza , Ahmad Mansur , Suratman Mohd Nazip , Abu Falah
Published: December 2015

The aim of this study was to determine the bending strength of finger joint of Kelat wood (Syzygiumspp.) bonded using Phenol Resorcinol Formaldehyde (PRF). Three finger-jointed Kelat wood with finger length of 12 mm, 13 mm and 15 mm respectively were manufactured and tested. In addition, the effects of different orientation (horizontal and vertical) of fingers were also examined. Bending tests were carried out to determine the Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) of the finger jointed samples in accordance to BS EN 373 standard. The results show that 15 mm finger length exhibited significantly higher means of MOE and MOR with the values of 17635.12 MPa and 72.59 MPa respectively, as compared to the shorter finger length (p≤0.05). This suggests that the bending strength was influenced by the finger length. The result also shows that bending strength of vertical finger joint is not significantly different compared to horizontal finger joint (p≥0.05). Therefore, the results obtained in this study is useful to provide base line data for a subsequent work which involve the manufacturing of glued laminated timber (glulam) from this timber species.
Thermal Conductivity of Paraffin Wax as Microencapsulated Phase Change Material (PCM) Coated on Polyester Fabric
Authors: Mahamad Dom Abu Bakar , Tulos Najua , Wan Ahmad Wan Yunus , Mohd Ahmad Faiza , Yahya Mohamad Faizul
Published: December 2015

This research works involves the production of microencapsulated phase change material (PCM) in which paraffin wax was used as the core components with sebacyol chloride (SC) and hexamathylene diamine (HMD) as the shell component. The microencapsulated PCM was characterized using Fourier Transform Infrared (FTIR) and scanning electron microscopy (SEM). Thermal energy storage capacity was measured by differential scanning calorimetry (DSC) while thermal conductivity was measured by thermal gravimetric analysis (TGA). The microencapsulated PCM were found to have a regular spherical shape with a size of 50µm while FTIR indicated that the microencapsulation process occurs due to the existence of alkyl group (C-H) and carbonyl group (C=O) in the spectra. DSC analysis shows that the paraffin start to melt at 47°C to 56°C with thermal energy storage capacity of 140.097 J/g and 114.766 J/g for sample A and sample B respectively. It was found that higher value of thermal energy storage resulting to lower thermal conductivity, which can be used as a thermal barrier in various applications.
An Efficient Numerical Simulation for a Fuzzy Kinetic Model Arising in Palm Oil
Authors: Ahmadian Ali , Ismail Fudziah , Senu Norazak , Salahshour Soheil , Ghaemi Ferial
Published: December 2015

Although the wide applications of the fractional order of dierential equations hasbeen reported in the physics, astronomy, and bioengineering elds, little attention has beenpaid to the fractional kinetic models in the literature. In this research, we are conned with theapplication of Jacobi polynomials for solving fractional order of l dierential equation arising inchemical reaction model into the Palm oil in the sense of fuzzy context. The results demonstratethe capability of the method which can be a reliable numerical technique to be utilized in thesimilar reaction models.
Synthesis of Carbon Nanotube-Carbon Nanosphere on the CF Surface by CVD
Authors: Ghaemi Ferial , Yunus Robiah , Jassim Lina , Ahmadian Ali , Ismail Fudziah
Published: December 2015

In the current work, the synthesis of carbon nanotubes (CNTs) and carbon nanospheres (CNS’s) has been investigated by applying the chemical vapor deposition method in a one-step sample preparation. In this method, iron nitrate non-hydrate (Fe(NO3)3.9H2O) and acetylene (C2H2) have been used as the catalyst source and carbon source, respectively, to grow CNT directly on the CF surface at 700°C and then CNS’s were synthesized on the CNT layers at 900°C under a 250sccm gas flow rate (40%N2, 40%H2, 20% C2H2). According to the SEM and TEM micrographs from the resultant carbon nanoparticles, the diameters of the CNTs and CNS’s have been estimated about 30-50nm and 300-400nm, respectively.
The Influence of Single Based Binder of Palm Stearin in HAP Feedstock on Rheological Properties Used for Ceramic Injection Moulding (CIM)
Authors: Abd Aziz Siti Norazlini , Ali Nurul Huda M. , Abu Bakar Mimi Azlina , Subuki Istikamah , Ismail Muhammad Hussain
Published: December 2015

Development of binder system based on natural resources is one the main interest among researchers in ceramic injection moulding (CIM) with the main aim of processibility of complex biomedical implant. In this paper, the influence of single binder comprised of palm stearin mixed with HAP powder was investigated. The powder and binder mixture, generally known as feedstock was analyzed for its flowability in order to get some insight for injection moulding purposes. Two different mixing temperatures were investigated for preparing the feedstock; 160°C and 70°C. The feedstocks viscosity was then evaluated using a capillary rheometer at temperature range from 70°C to 90°C. The results clearly showed that the use of 100% palm stearin was promising in providing required pseudoplastic flow for injection molding. The injection molding process can be carried out at relatively low temperature in comparison with the conventional binder systems used.
Preliminary Study on Curing of Thick Rubber Article
Authors: Ibrahim Siti Zulaikha , Said Che Mohd Som , Ahmad Mohamad Asri , Samsuri Azemi
Published: December 2015

In this study, several batches of natural rubber (SMR L) were compounded with three different types of accelerators, which were N-cyclohexylbenzothiazole-2-sulphenamide (CBS), diphenylguanidine (DPG) and zinc diethyldithiocarbamate (ZDEC). ZDEC is known as an ultrafast accelerator. The rubber compounds were cured at 140°C, 130°C, 120°C, 110°C and 100°C in accordance with the temperature gradients observed within the thick rubber block. The main aim of this study is to cure the rubber at each temperature region to the same cure time as that of the outermost region (20 minutes at 140°C). The amount of sulfur and accelerator were adjusted accordingly at each curing temperature to match the state of cure at 140°C. The state of cure of of the vulcanized rubbers were measured using hardness and tensile strength. The same state of cure is achieved if the hardness and tensile strength value are within ±2 IRHD and ±3 MPa, respectively with that of the control vulcanized rubber (hardness and tensile strength cured at 140°C). The results shows that the hardness and tensile strength of the vulcanized rubber at each temperature region are within the expected margins. The results clearly indicated that the type and amount of accelerators, and the amount of sulfur were correctly chosen at each temperature.
Determination of White Root Infected Rubber Tree through Dielectric Characteristic in Latex
Authors: Mohd Azmi Azrie Faris , Hashim Hadzli , Sulaiman Mohd Suhaimi , Wahid Nur Baiti , Khairuzzaman Noor Aishah , Mohd Sampian Ahmad Faiz
Published: December 2015

White root disease caused byRigidoporus lignosusis one of most serious disease in rubber plantation. Until now, research about white root disease relates to electrical properties is still less. Hence, this research investigated the differences in electrical properties of healthy and white root disease through dielectric constant value. Seventy six samples of healthy and white root disease respectively were collected from rubber estate located in Kota Tinggi, Johor. Measurement of dielectric constant value for both conditions of latex has been done using Electrochemical Impedance Spectroscopy (EIS) in the range of frequency between 50 Hz up to 10 kHz. The result obtained from this measurement was proceeding with the statistical analysis to analyze the differences of healthy and white root disease. It was found that at frequency 150 Hz, the dielectric constant of healthy and white root disease have show significant differences.
Characterizing Mechanical Properties of Peroxide-Vulcanized Natural Rubber Latex Films
Authors: Ramli Roslim , Jaapar Jefri , Jaswan Singh Manroshan Singh , Maqsood Ul Haque Siti Noor Suzila , Yatim Amir Hashim Md
Published: December 2015

Natural rubber latex is the material of choice for the fabrication of thin elastic films in many products such as gloves and condoms owing to its high strength, elasticity, comfort in use, good barrier properties and ‘green image’ [1, 2]. This unique combination of characteristics has its origins in the intrinsic properties of the crosslinked polymer network within the rubber matrix. The crosslinking of rubber hydrocarbon chains by free radicals generated from peroxide has been discovered for many years [3]. In peroxide crosslinking reactions, organic peroxide decomposes to produce reactive free radicals that will react to release hydrogen ions from the carbon hydrogen in the polymer chain, encouraging formation of free radicals on the rubber molecular chains. As the free radicals react with the polymer chains, the carbon hydrogen in the chains act as reactive centre that combines with centres of other rubber chains to form a network of carbon to carbon bonds which serve as crosslinks [3, 4].
Water Resistance and Tensile Strength of High Density Polyethylene (HDPE) Composites
Authors: Mohd Ayob Nurul Atiqah , Ahmad Mansur , Mohd Khairuddin Nurul Nadia
Published: December 2015

In this paper, three type of natural-fibre reinforced polyethylene were produced. They are the coconut coir reinforced polyethylene (RPCC), kenaf reinforced polyethylene (RPKC) and bamboo reinforced polyethylene (RPBC). Water absorption test, thickness swelling test and tensile test of the different natural fibre composites were carried-out. The mass of HDPE and natural fibre were based on percentage of filler loading. Each board types were produced with two fibre ratios which are at fourty percent and thirty percent. The preparation of the test sample is according to ASTM D1037 and ASTM D638. The tensile modulus of elasticity, tensile stress, water absorption and thickness swelling of kenaf and bamboo reinforced polyethylene composites were found to increase with increasing fibre weight fraction. Kenaf and bamboo composites showed compatible result for tensile stress and tensile modulus of elasticity while coconut coir appears to be otherwise. However, coconut coir fibre composites displayed comparable results to kenaf and bamboo for both water and thickness swelling. There were significant differences in both tensile properties and the percentage of the water absorption among composites.
Effect of Compounding Ingredients and Crosslink Concentration on Blooming Rate of Natural Rubber Compounds
Authors: Yasin Ummu Qani’ah , Kamarun Dzaraini , Said Che Mohd Som , Samsuri Azemi
Published: December 2015

Blooming is a diffusion process whereby compounding ingredients dispersed in rubber matrix migrate to the rubber surface and appears as a layer of white crystalline material. Blooming is a typical phenomenon observed in rubber compounds which could lead to problems such as discoloration and poor appearance of products as well as loss of adhesion. Cause of blooming was still unclear and this research was carried out to identify the effect of compounding ingredients and crosslink concentration on blooming rate in natural rubber compounds. In this project 6 natural rubber formulations based on three different types of compounding ingredients at two different concentrations of crosslinker were compounded and tested for their blooming characteristics. Sulphur, wax and dithiocarbamate as the compounding ingredients were mixed with natural rubber in the presence of 1 and 6 phr of peroxide as the vulcanizing agents. The effect of crosslink concentration on blooming rate of the compounded rubber was then determined. The blooming rate was determined by the weight of the blooming material on the rubber surface as a function of time. The blooming rate was found to be affected by the types of compounding ingredients and crosslink density of rubber. Wax with 6 phr of peroxide showed the highest amount of bloom and the highest blooming rate while the dithiocarbamate accelerator with 1 phr peroxide showed the lowest amount of bloom and the lower blooming rate. As expected, all the compounding ingredients showed an increase of crosslink concentration as the loading of peroxide increases. The blooming rate was also found to be affected by the crosslink concentration of rubber. As the crosslink concentration increases, the rate of blooming increases as were shown by wax and dithiocarbamate accelerator. However, sulphur showed the opposite trend whereby the crosslink concentration increases but the blooming rate decrease. This could be due to the high peroxide level retarding the sulphur blooming process.
Thermal Properties and Mechanical Performance of Unsaturated Polyester/Phenolic Blends Reinforced by Kenaf Fiber
Authors: Mohd Mahadar Marliana , Hassan Azman , Mohd Yunus Nor Yuziah , Abdul Khalil H.P.S. , Mohamad Kassim Mohamad Haafiz
Published: December 2015

In this study, unsaturated polyester resin (UP) is blended with resole type phenolic resin (PF) to develop a material with good flame retardancy. The UP/PF resin blends are expected to show good compatibility when compounded with natural fibers which in this research is kenaf fiber. The thermal properties were investigated by thermogravimetric analysis (TGA). The char yields of the UP/PF blends reinforced kenaf composite increased with PF content. The degradation temperature of the composite at 50% weight loss rose to 410.13°C as the PF content was increased to 40%. The result shows with additional of PF to UP resin enhance the thermal stability of the composite. Meanwhile the mechanical performance of UP/PF kenaf composite were evaluated and compared with neat UP and PF reinforced with kenaf fiber using tensile and impact testing. The mechanical properties of all resin blends at different mixing proportions slightly decrease by increasing the phenolic content but shown an improvement as compared to the PF kenaf fiber composite. The fracture surface morphology of the tensile testing samples of the composites was performed by scanning electron microscopy (SEM).
Rubber-Solvent Interaction Parameter (χ1,2) of NR/SBR Rubber Blend Solution in Determination of Crosslink Concentration for Vulcanized Rubber Blend
Authors: Dzulkifli Azreen Izzati , Said Che Mohd Som , Han Chan Chin , Mohd Ahmad Faiza
Published: December 2015

Crosslink concentration is an important property affecting the major characteristic of cured rubber. One of the important parameter to determine the crosslink concentration of a vulcanized rubber by swelling measurement is the rubber-solvent interaction parameter known as ‘kai’ value denoted as χ. For single rubber, the χ value is known however, the χ1,2 for rubber blends are unknown. This research concerned with the investigation to determine the χ1,2 for rubber blends solution (uncured rubber). Natural rubber (NR) and styrene butadiene rubber (SBR) rubber blends solution were blend at 7 different ratios of 100/0, 80/20, 70/30, 60/40, 50/50, 40/60 and 0/100 and were dissolved in toluene. The χ1,2 value of each rubber blends were determined based on the intrinsic viscosity measurement. Crosslink concentrations of vulcanized rubber blends obtained from the swelling measurement were then compared against the value determined from simple extension measurement (stress-relaxation method). This cross-checking was to ensure the accuracy and reliability of χ1,2 value for rubber blends solution.
Aspects of Titanate Coupling Agents and their Application in Dental Polymer Composites: A Review
Authors: Elshereksi Nidal W. , Ghazali Mariyam J. , Muchtar Andanastuti , Azhari Che H.
Published: December 2015

Silanes are extensively used in dental composites to facilitate chemical bonding among the phases of composites. Despite their popularity, the dental application of silanes as coupling agents is still restricted by a few limitations, which include their hydrolytic instability in aqueous oral environment and their inefficiency to bond with nonsilica fillers. Titanate coupling agents can provide good interphase bonding, improve mechanical properties, enhance filler homogenous dispersibility, and modify the rheological behavior of composites. Moreover, moisture resistance can be improved by adding a small amount of titanates. This review aims to evaluate the efficiency of using titanate coupling agents in dental polymer composites and denture bases, particularly when titanium-based fillers are impregnated.
STUDY OF TEMPERATURE PROFILE ON VARIOUS LAND USE AND LAND COVER FOR EMERGING HEAT ISLAND
Authors: Franco Sainu , Mandla Venkata Ravibabu , Rao K. Ram Mohan , M Pramod Kumar , P.C. Anand
Published: December 2015

Greater Hyderabad a twin city in earlier days, has grown into a tricity of Cyberabad - Hyderabad – Secunderabad. This concentrated development with impetus on industrialization has led to unprecedented urbanization and sprawl, resulting in heavy population growth and ultimately raising serious challenges such as traffic congestion, enhanced Green House Gas (GHG) emissions causing climatic changes apart from over-use of basic amenities and infrastructure. This study shows that urban areas have grown from a mere 172 sq km of MCH (Municipal Corporation of Hyderabad) in the 1970’s to a whopping 1905 sq km at present, currently known as the Greater Hyderabad Metropolitan Corporation. The phenomenon of Urban Heat Island (UHI) can be observed in several localities. The pattern of growth of Greater Hyderabad and its repercussions on the local climate are studied with the help of geospatial technologies. An increase of ~20C to 2.50C is observed over the last 2 decades. The Vegetation and water bodies also show a sharp decline.
Evaluation of relationship of hand wrist radiograph, cervical vertebral maturation with mandibular growth as skeletal maturity indicators in children
Authors: Mohammad Ziauddin , Namineni Srinivas , Cheruku Sampath Reddy , Penmetcha Sarada , Munnangi Surendra Reddy , Mallineni Sreekanth Kumar
Published: December 2015

Objective: To study the correlation between mandibular growth variables using linear measurements of ramus, body of the mandible and total mandibular length with skeletal maturity indicators such as hand wrist radiographs and cervical vertebral maturation. Materials and Methods: A total of 315 patient-records (lateral cephalograms and hand-wrist radiographs) in the age group of 10-13 years were involved. The cephalometric measurements, representative of the mandibular growth, Condylion-Gonion (Co-Go), Condylion-Gnathion (Co-Gn), Gonion-Gnathion (Go-Gn), and posterior-most point of the mandibular condyle-pogonion (Fg-Pg) were traced (McNamara method). The correlation of mandibular growth variables with hand wrist parameters and cervical vertebrae maturation were assessed separately in male and female. Pearson’s correlation was used for analysis (Statistical Package for Social Sciences version 17). Results: Only 80 subjects were included in final analysis. A highly significant correlation was found among hand wrist parameters, and mandibular growth variables (P < 0.001) in both genders. Among males, there was a highly significant correlation between cervical vertebral maturation and mandibular growth variables (P < 0.001), whereas Co-Go has a significant correlation with C2Conc, C3Conc, and C4Conc (P < 0.05). In females, Co-Gn, Co-Go, Go-Gn, and Fg-Pg were significantly correlated with C3Conc and C4Conc (P < 0.001). Conclusion: Both the cervical vertebral maturation and mandibular growth variables can be accessed on the lateral ephalogram itself for the evaluation of the skeletal maturity, as effective as a hand wrist radiograph in males and females.
Myriad Functions of Stanniocalcin-1 (STC1) Cover Multiple Therapeutic Targets in the Complicated Pathogenesis of Idiopathic Pulmonary Fibrosis (IPF)
Authors: Ohkouchi Shinya , Ono Manabu , Kobayashi Makoto , Hirano Taizou , Tojo Yutaka , Hisata Shu , Ichinose Masakazu , Irokawa Toshiya , Ogawa Hiromasa , Kurosawa Hajime
Published: December 2015

Idiopathic pulmonary fibrosis (IPF) is an intractable disease for which the pathological findings are characterized by temporal and spatial heterogeneity. The pathogenesis is composed of myriad factors, including repetitive injuries to epithelial cells, alterations in immunity, the formation of vascular leakage and coagulation, abnormal wound healing, fibrogenesis, and collagen accumulation. Therefore, the molecular target drugs that are used or attempted for treatment or clinical trials may not cover the myriad therapeutic targets of IPF. In addition, the complicated pathogenesis results in a lack of informative biomarkers to diagnose accurately the status of IPF. These facts point out the necessity of using a combination of drugs, that is, each single drug with molecular targets or a single drug with multiple therapeutic targets. In this review, we introduce a humoral factor, stanniocalcin-1 (STC1), which has myriad functions, including the maintenance of calcium homeostasis, the promotion of early wound healing, uncoupling respiration (aerobic glycolysis), reepithelialization in damaged tissues, the inhibition of vascular leakage, and the regulation of macrophage functions to keep epithelial and endothelial homeostasis, which may adequately cover the myriad therapeutic targets of IPF.
О расходимости треугольных и эксцентрических сферических сумм двойных рядов Фурье
Authors: Karagulyan Grigori Artashesovich
Published: December 2015

Строится непрерывная функция на торе с почти всюду расходящимися треугольными суммами двойных рядов Фурье. Аналогичная теорема устанавливается также для эксцентрических сферических сумм.
Библиография: 14 названий.
Profile of Cytokines and Chemokines Triggered by Wild-Type Strains of Rabies Virus in Mice
Authors: Appolinário Camila Michele , Allendorf Susan Dora , Peres Marina Gea , Ribeiro Bruna Devidé , Fonseca Clóvis R. , Vicente Acácia Ferreira , de Paula Antunes João Marcelo A. , Megid Jane
Published: December 2015

Rabies is a lethal infectious disease that causes 55,000 human deaths per year and is transmitted by various mammalian species, such as dogs and bats. The host immune response is essential for avoiding viral progression and promoting viral clearance. Cytokines and chemokines are crucial in the development of an immediate antiviral response; the rabies virus (RABV) attempts to evade this immune response. The virus's capacity for evasion is correlated with its pathogenicity and the host's inflammatory response, with highly pathogenic strains being the most efficient at hijacking the host's defense mechanisms and thereby decreasing inflammation. The purpose of this study was to evaluate the expression of a set of cytokine and chemokine genes that are related to the immune response in the brains of mice inoculated intramuscularly or intracerebrally with two wild-type strains of RABV, one from dog and the other from vampire bat. The results demonstrated that the gene expression profile is intrinsic to the specific rabies variant. The prompt production of cytokines and chemokines seems to be more important than their levels of expression for surviving a rabies infection.
Effects of Humidity Variation on the Hantavirus Infection and Hemorrhagic Fever with Renal Syndrome Occurrence in Subtropical China
Authors: Xiao Hong , Huang Ru , Gao Li-Dong , Huang Cun-Rui , Lin Xiao-Ling , Li Na , Liu Hai-Ning , Tong Shi-Lu , Tian Huai-Yu
Published: December 2015

Infection rates of rodents have a significant influence on the transmission of hemorrhagic fever with renal syndrome (HFRS). In this study, four cities and two counties with high HFRS incidence in eastern Hunan Province in China were studied, and surveillance data of rodents, as well as HFRS cases and related environmental variables from 2007 to 2010, were collected. Results indicate that the distribution and infection rates of rodents are closely associated with environmental conditions. Hantavirus infections in rodents were positively correlated with temperature vegetation dryness index and negatively correlated with elevation. The predictive risk maps based on multivariate regression model revealed that the annual variation of infection risks is small, whereas monthly variation is large and corresponded well to the seasonal variation of human HFRS incidence. The identification of risk factors and risk prediction provides decision support for rodent surveillance and the prevention and control of HFRS.
Travel Vaccines Enter the Digital Age: Creating a Virtual Immunization Record
Authors: Wilson Kumanan , Atkinson Katherine M. , Bell Cameron P.
Published: December 2015

At present, proof of immunization against diseases such as yellow fever is required at some international borders in concordance with the International Health Regulations. The current standard, the International Certificate of Vaccination or Prophylaxis (ICVP), has limitations as a paper record including the possibility of being illegible, misplaced, or damaged. We believe that a complementary, digital record would offer advantages to public health and travelers alike. These include enhanced availability and reliability, potential to include lot specific information, and integration with immunization information systems. Challenges exist in implementation, particularly pertaining to verification at border crossings. We describe a potential course for the development and implementation of a digital ICVP record.