bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal Design of Composite Wing-Box by Genetic Algorithm
Authors: Pu Guang Rong , Mu Peng Gang
Published: November 2014

With the increasing use of composite materials in aviation structures, stability and weights of wing-box are important projects that engineers care about. In this paper, the genetic algorithm is chosen to deal with the conceptual design problems of composite wing-box. For the more excellent capabilities in optimization computation of multi-dimensional functions, particularly when overcoming local-best solutions, genetic algorithm is presented to determine the design variables of complicated wing-box. Optimization algorithm is realized with MATLAB software, which calls the finite element program MSC.Nastran to get buckling load factors, and structural layout, thickness of plies and minimum weight of wing-box are obtained simultaneously. The results show that the approach proposed is available, effective to preliminary design of the mainly aeronautical structures.
Research on Evaluation Method of Occupant Neck Injury in Whiplash Test
Authors: Gu Hai Ming , Lou Lei , Chen Chao
Published: November 2014

As road traffic becomes more and more crowed nowadays, rear impact has become one of the most common forms of traffic accident. According to a survey, up to 78.2% of rear impact can cause occupant neck injury. Up to now, E-NCAP, J-NCAP, IIHS and C-NCAP have set whiplash test in officially. But because of the uncertainty of injury mechanism, none of the countries has reached an agreement on the evaluation method of occupant neck injury. Comparison and analysis of whiplash evaluation methods are made, from aspects of collision waveform, speed, evaluation criteria, calculation method, criteria limit, etc. The annual C-NCAP whiplash tests are set as statistical sample and an analysis of the relationship between lost points and influential factors is carried out in order to find the part that needs to be perfected. Finally, effective suggestions are put forward for the improvement of evaluation method of occupant neck injury in whiplash test.
Sensorless Speed Control of Permanent-Magnet Synchronous Motor Based on a New Sliding-Mode Observer
Authors: Han Fei Fei , Wang Zhong Hua , Han Tong Yi
Published: November 2014

In this paper, a new sensorless speed control strategy which is based on a new sliding-mode observer (SMO) is proposed for permanent-magnet synchronous motor (PMSM). The rotor position is estimated by the back electromotive force (EMF). In order to improve the estimation accuracy, the speed estimator is proposed, which replace the method of direct differential. The Lyapunov theory is applied to prove the stability of the designed system. The simulation results indicate that the proposed sensorless speed control system of permanent-magnet synchronous motor based on a new sliding-mode observer is effective and feasible.
The Analysis of Storage Efficiency in VMware Virtualization Environment
Authors: Zuo Hua Hong , Chen Xiao
Published: November 2014

This article which compares four different schemes of storage in virtualization environment tests the efficiency of system storage from application and management. The article based on test data analyses the advantages, the disadvantages and the suitable application scenarios of each scheme and gives some feasible advice of comprehensive application in various storage styles. It deserves strong theoretical and practical value.
Research on Personalized Document Retrieval and Ranking Strategy
Authors: Tang Hai , Zhu Xian Cheng
Published: November 2014

In order to obtain proper text information consistent with the users’ cognitive level, a new personalized retrieval method is proposed for the distant learners. At first the user’s personalized cognitive structure is established and this structure can represent the users’ cognitive level formally. Then related concept can be extended around the keywords, which usually reflect their focus of attention. How to extend depennd on the semantic distance which should be measured by some new formula in this article. At last these queried documents should be ranked according to the user’s cognitive level and the difficulty of the document containt. Experiments show that even if some different learners use the same keywords, the query result is consistent with their cognitive level respectively.
Research on Effect of Cr3C2 Addition on Microstructure and Mechanical Properties of Ti(C,N)-Based Cermets
Authors: Wei Hai Long , Lei Hai Yan , Zhong Guo Xiong , Yu Hai Zhou , Feng Ping
Published: November 2014

Four Ti (C,N)-based cermets with Cr3C2 content of 0.3%, 0.6%, 0.9% and 1.2 % in mass ratio were sintered in vacuum at 1430oC, 1450oC, 1465oC and 1480oC. The mechanical properties of the specimens were determinted and microstructures were observed using the scanning electron microscope (SEM) to study the effect of Cr3C2 content on mechanical properties and microstructure. The results show that the four Ti (C,N)-based cermets sintered at 1465oC have the best overall mechanical properties; and among them, the cermet with 0.6% Cr3C2 has the best overall mechanical properties, i.e. transverse rupture strength (TRS) 1967MPa, hardness 1556HV and fracture toughness (KIC) 9.5MPa.m1/2. With the increase of Cr3C2 content, the black core volume fraction firstly increases and then decreases, the white core decreases in a progressive and continuous manner, the rim phase firstly increases and then decreases, the binder phase firstly decreases and then increases.
Particle Swarm Optimization for Batch Scheduling Problem in Flexible Workshop
Authors: Tang Qi , Zhou Xiao Ye , Tang Jian Xun
Published: November 2014

This paper puts forward an improved optimization algorithm for batch scheduling problem in flexible workshop. Code is designed as batch selection probability of different production tasks and defined as production plan through effective decoding procedure. Simulation experiment on the performance of this algorithm is conducted in instances generated randomly. The results show that this algorithm has good performance.
Driving Model of Implementing Mass-Customization Manufacturing in Cluster Supply Chain
Authors: Liu Chun Ling , Liu Shuang Shuang
Published: November 2014

To explore the attributes of cluster supply chain, and provide its driving model (2P&2BP) for more effective and more efficient way in implementing mass customization. The paper analyzes cluster supply chain driving model for implementing mass customization manufacturing using data from case study from 8 garment and IT industrial clusters. In process of implementing mass customization, we found that cluster supply chain has supplying level, marketing level and supplementing level to support its driving model (2P&2BP: Pull/push/burst power/bottleneck press) rather than conventional pull\push model. thus SMEs (small and medium-sized enterprises) in industrial cluster would have chances to extensively participate cooperate with core companies in the form of supply chain, thus expanding gradually.
Revenue Sharing Contract of Green Supply Chain under Manufacturer Risk-Aversion
Authors: Jiang Shi Ying , Ma Chun Yan
Published: November 2014

Background on two stages green supply chain consisting of a manufacturer and a retailer, considering the degree of risk aversion and product greenness, consumer preferences and other factors, the centralized decision-making game model and manufacturer-leading Stackelberg game model are established.Then two game models are compared. The interaction of product greenness, wholesale price, product price,and risk aversion utility for manufacturers and retailers are also disscussed. Finally, the revenue sharing contract is applied to coordinate the green supply chain . The results show that:(1) In the centralized decision-making model, there is a critical value of the product green degree; (2)In manufacturer-leading Stackelberg game model, the higher the green degree of the product, the higher the manufacturer's wholesale price,and the wholesale price increases as risk aversion degree of manufacturers improves;(3)The revenue sharing contract can coordinate this type of green supply chain under manufacturers risk-averse.
Current Status and Analysis of the Study on Quality Control
Authors: Liu Guo Cai , Pang Hong Xun , Xu Xin Feng
Published: November 2014

During the past years, Automatic control theory was founded. Especially in the foundation of engineering control theory, control science has formed a number of branches, such as population control, large system cybernetics, biological control and etc. Quality control of product in its whole life cycle is an important research object, especially driver development strategy in national innovation, quality and efficiency should be more collaborative developing. However, that several major engineering practice, the quality control of the situation is very serious, and urgent need to further study on the quality control theory.This paper puts focus on quality control and surveys the source of quality control, especially makes attentions to the development of theory method among quality control, control theory and engineering control theory, and then shows the developing map between quality control and control theory and finds that the quality control system caused by the fusion between quality control and control theory is one new method to break the bottleneck and suggests 4 block models of the quality control system.
Integrated Model of Cluster Supply Chain and Logistics Park
Authors: Qi Yu Lan , Liu Shuang Shuang
Published: November 2014

The organizational succession in cluster supply chain is not only a primary upgrading way of industrial cluster, but also a basis of integrating industrial cluster and Logistics Park. This paper analyzes how to integrate organizational succession in cluster supply chain and Logistics Park according to the logistics features of organizational succession in cluster supply chain, and puts forward three integrated models. Meanwhile, through the case study of IT industry in Suzhou, the logistics evolving regulation of organizational succession in cluster supply chain is explored, and some relevant conclusions and suggestions are drawn at last.
Ergnomics Application in Machine Tool Design
Authors: Mu Cun Yuan , Fan Min
Published: November 2014

The paper discusses the ergonomics problems about eye height, operating handles, bottoms etc. in machine tool design. Points out the misapprehension of human body average dimension, gives some constructive design data according to different human body dimension percentage to design different operating elements. It can be the reference for designers in machine tool industrial.
Effects of Melt Holding Time on as Cast Microstructure and Tensile Properties of Sr-Modified AS31Alloy
Authors: Wang Jin Wei , Zhou Ji Xue , Ma Bai Chang , Tang Shou Qiu , Chu Fu Min , Yang Yuan Sheng
Published: November 2014

Melt holding time has important influences on the modification effect of Sr modified AS31 alloy. Effects of different melt holding time (30min, 60min, 90min and 120min) at 700°C on as cast microstructure and tensile properties both at ambient temperature and elevated temperature of Sr-modified AS31 alloy were studied. There exist polyhedral shape, fine fibers shape and a few Chinese script Mg2Si particles in Sr-modified AS31 alloys. And the average grain size is smallest in Sr-modified AS31 alloys with holding time at 700°C for 30min. The ultimate strength, yield strength and elongation at both ambient temperature and 150°C decrease gradually when the melt holding time increases from 30min to 120min. In the process of smelting of Sr-modified AS31. The burning loss of Sr element becomes more serious with the prolongation of melt holding time, which contributes to the modification effect reducing.
Influence of Heat Treatment Process on the Structures and Properties of Grate Bars Used in Sintering Trolley
Authors: Li An Min , Ma Ding , Zheng Qi Feng , Chen Ruo Huai , Huang Zu Jiang , Zhang Zi Jun , Li Qiang
Published: November 2014

The as-cast structure of grate bar used in sintering trolley is primarily comprised of austenite and eutectic (eutectic austenite and eutectic carbide). The austenite is dendrite, while the carbide is reticular and chrysanthemum-like. The grate bars were quenched and tempered under various temperature (one set of samples: quenching (975~1050°C); the other: quenching (1000°C) + tempering (240~600°C)). With rise in quenching temperature, the content of martensite increases and gradually stabilizes, and the hardness increases and then decreases (the maximum is 61.5HRC). For the tempered simple, the strip-like carbides gradually become smaller, shorter and homogenized; the resistance to temper softening is high and the maximum hardness is 58HRC; the wear resistance gradually decreases and is lower than that of as-cast one when the temperature is higher than 480°C. The heat treatment process to improve the service properties of grate bars is: quenching (1000°C, 2.5h, and air-cooling) + tempering (300~420°C, 2.5h, and air-cooling).
Characterization of Activated Carbon from Sugar Cane Husk
Authors: binti Jamion Nurul’ Ain , binti Mohamed Siti Mazleena
Published: November 2014

Interface adsorption of gases and liquid on a clean solid surface could be due to the physical or chemical adsorption. In this study, the activated carbon was prepared from sugar cane husk (powder and granular form) using phosphoric acid (H3PO4) as activating agent. Sample was activated at 500°C for two hours in the furnace and washed using vacuum method. Besides, surface area of activated carbon was defined using Single Point Brunauer-Emmett-Teller (BET) Nitrogen Gas. The physico-chemical characteristics of the prepared activated carbon were characterized by Fourier-Transformed Infrared Spectroscopy (FTIR), gravimetric method, and Field Emission Scanning Electron Microscopy (FESEM). The adsorption study by surfactants, namely CTAB (cationic) and TX-100 (non-ionic) were investigated. The experimental results showed that a good activated carbon was prepared from sugar cane husk granular (SCH-G) gave the highest BET surface area of 860.18 m2/g and the adsorption capacity of SCH-G activated carbon at 25°C using TX-100 (205.81 mg g-1) was greater compared to the CTAB (108.20 mg g-1). This study has shown that the sugar cane husk was a good activated carbon and has potential to be used as adsorbent for the removal of surfactants from aqueous solutions.
Bioremediation of Biodiesel/Diesel Blend (B50) in Soil Contamination by Using Pseudomonas putida
Authors: Sunar N.M. , Emparan Q. , Karim Ahmad Tarmizi Abdul , Maslan M. , Mustafa F. , Khaled N.
Published: November 2014

The biodiesel fuels nowadays are attracting worldwide attention as blending components or direct replacements for diesel fuel in conventional diesel engines. This study aims to investigate the effectiveness of Pseudomonas putida as oil-biodegradable agent in soil contaminated with biodiesel/diesel blends (B50). The effectiveness on bioremediation has been conducted by examining several physico-chemical tests on biodiesel/diesel-contaminated soil before and after seeding of Pseudomonasputida. The spillage stimulation of B50 was conducted at laboratory scale for 24 days of incubation time. The results show that the bioremediation treatment able to remove up to 82%, 54%, 38% and 10% of nitrogen, sulfate, phosphate and organic carbon, respectively. The pH of soil sample was changed from pH 7.42 (Day 0) to pH 6.38 (Day 24) after the treatment. Meanwhile, the moisture content in the sample has increased from 25.61% (Day 0) to 31.83% (Day 24). All results show the good indication of quality improvement for polluted soil after treated with Pseudomonas putida. It is apparent from the acquired results that the application of Pseudomonasputida is suitable as effective microorganism and potentially useful as oil-soil biodegradable agent in polluted soil.
Calcium Carbonate Production through Direct Mineral Carbon Dioxide Sequestration
Authors: Azdarpour Amin , Junin Radzuan , Asadullah Mohammad , Hamidi Hossein , Manan Muhammad , Mohamad Daud Ahmad Rafizan
Published: November 2014

Mineral carbon dioxide sequestration provides a leakage free and permanent method of CO2 disposal to produce environmentally benign and stable solid carbonates. FGD gypsum as a source of calcium was proposed as the potential feedstock in this study. The purpose of this laboratory study was to investigate the effects of reaction parameters such as CO2 pressure, reaction temperature, particle size, and ammonia solution concentration on calcium carbonate purity through Merseburg process. Increasing the reaction temperature as well as the pressure was very effective in improving the calcium carbonate purity. High purity calcium carbonate was produced when reaction temperature and CO2 was increased to 400 °C and 70 bar, resulting in 93% and 94% purity, respectively. Experimental results showed that reducing particle size was also effective in enhancing the calcium carbonate purity in which the smallest particles produced higher purity calcium carbonates rather than larger particles. The role of ammonia solution on calcium carbonate purity was found to be beneficial in improving the calcium carbonate purity in which increasing the ammonia solution increased calcium carbonate purity significantly in all experiments.
Characterization of Wet Impregnation Method for Catalytic Microcombustor by Using Platinum
Authors: Muhamad Nazri Murat , Muhamad Azman Miskam , Mohd Azmier Ahmad , Zainal Alauddin Zainal Alimuddin , Mohammad Zulfikar Ishak
Published: November 2014

The wet impregnation method for catalytic microcombustor was characterized by using platinum as a catalyst. The main purpose of this study is to increase the surface porosity of the catalyst support. A high surface porosity indicates that a high amount of catalyst was deposited within the surface areas. The performance of the catalytic microcombustor improves with increasing catalytic surface area. The stainless steel catalyst support was treated with sulfuric acid solution containing polyvinyl (3.89 wt%) and propargyl alcohol (1.48 wt%). Combustion test was performed using LPG-air to test the performance of the catalyst. The surface support treated with polyvinyl (PVA) showed a higher surface porosity and combustion blow-out limit compared with propargyl alcohol. The combustion mode changes from surface to submerged combustion after the catalyst was deposited in the support surface.
Effect of Weld Side Combination on Mechanical Properties of Double Sided Friction Stir Welded 5083 Aluminum Alloy
Authors: Zubaydi Achmad , Muhayat Nurul , Santosa Budie , Setyawan Dony
Published: November 2014

Double sided friction stir butt welds on 6 mm thick of 5083 aluminum alloy were produced. Two variants of the weld side combination, different weld side (DS) and same weld side (SS), have been made to investigate the effect of the weld side on mechanical properties.The SS is a double sided welding process that produces advancing side in one plate and retreating side in the other one. On the other hand, the DS is a double sided welding process that causes advancing side and retreating side in each plate. Tensile properties of the joints were evaluated and correlated with macrostructure and hardness. The weld side influenced the macrostructure and mechanical properties of welded joints. The different weld side (DS) had better mechanical properties than the same weld side (SS).
Facile Preparation of Co3O4 Nanoflower through Forced Hydrolysis
Authors: Basir Nor Irwin , Sharif Hussein Sharif Zein , Latif Ahmad Abdul , Azman Miskam Muhamad
Published: November 2014

One of the interesting structures in nanoCo3O4's preparation that have been reported fairly recent is the flower-like structure often referred as nanoflower. Several interesting applications involving Co3O4 nanoflower have also been reported. This paper present a facile approach to prepare Co3O4 nanoflower using one step forced hydrolysis technique using cobalt chloride hexahydrate as starting material as opposed to the standard two steps hydrothermal technique. The produced nanoscale Co3O4 is in agglomerate of nanorods producing a dandelion-like flower structure. The prepared Co3O4 is in hydrated and amorphous forms with a surface area of 62 m2/g and average pore size of 12 nm.
Photocatalytic Oxidative Desulfurization of Model Oil Using Cu/TiO2 Photocatalyst and Eutectic Based Ionic Liquid: Effect of Metal Loading
Authors: Mohd Zaid Hayyiratul Fatimah , Kait Chong Fai , Abdul Mutalib Muhammad Ibrahim
Published: November 2014

Titanium dioxide (TiO2) photocatalyts doped with copper metal at different metal loadings were successfully prepared and characterized. Photocatalytic oxidative desulfurization of model oil containing dibenzothiophene as the sulfur compound (100 ppm) was investigated using the prepared photocatalyst. The photocatalyst with 2.0 wt% Cu metal loading showed the best sulfur removal at 66.25%.
Corrosion Analysis of Carbon Steel Pipeline: Effect of Different Sulfuric Acid Concentrations
Authors: Azam Mohd Asyadi , Ibrahim Mohd Fuad , Zaimi Muhammad
Published: November 2014

Oil and gas industry has been hugely contributing any government income and this industry is highly required to control corrosion failures in pipelines which may potentially cause substantial human and economic losses. The objective of this study is to study the effect of sulfuric acid (H2SO4) electrolyte concentration to corrosion behavior of the internal surface of natural gas pipeline by using Tafel extrapolation method. Surface morphology of the samples is studied using optical microscope and scanning electron microscope to investigate the correlation between the corrosion rate and surface morphology. As results, the corrosion rate increases with higher concentration of H2SO4. Microscopic analyses also confirmed the presence of pitting corrosion, and micrometer thick of corrosion product was developed on the surfaces. The data can be used to managing the pipelines effectively and prevention method can be taken in order to extend the life span of the pipeline.
Empirical Equilibrium Study on Rice Husk and Eggshells as Low Cost Bioadsorbent for the Methylene Blue Removal
Authors: Razak Nurul Hanim , Ayob Md. Razali , Zainin M.A.M. , Hilwa M.Z.
Published: November 2014

Eggshells and rice husk, two types of notable agricultural waste were used as bioadsorbent to remove Methylene Blue dye (MBD) in aqueous solution. This study was to investigate the performance of these two bioadsorbents in removing MBD. The removal percentage, adsorption capacity, and porosity characterization were examined. The method applied was a physical filtration. UV-VIS Spectrophotometer was used to determine the efficiency of the bioadsorbents in MBD adsorption. The highest removal percentage at the most concentrated MBD were 51% and 98% for eggshells and rice husks respectively. Meanwhile the characterization of rice husks pore size and volume proves that higher adsorptivity towards dye compares to eggshells porosity. It was concluded that the eggshells and rice husks bioadsorbents was successful to treat industrial textile wastewater with rice husks as the most efficient bioadsorbent in removing MBD.
Synthesis and Characterization of Hollow Anatase TiO2 Spheres and its Application in the Photodegradation of γ-Lindane under Ultraviolet Light
Authors: Baharvand Afrouz , Mohd Yusof Alias , Ali Rusmidah , Sanagi Mohd Marsin , Chandren Sheela , Nur Hadi
Published: November 2014

Hollow anatase titania spheres have been synthesized using hydrothermally–prepared carbon spheres as the template. Here, the combination of hydrothermal process with sol–gel followed by calcination in air was done in order to obtain hollow anatase TiO2 spheres by utilizing fructose and tetrabutyl titanate (TBT) as the precursors. The structure and morphology of the products were characterized using various techniques, including Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermal gravimetric and differential thermal analysis (TG–DTA), scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). XRD showed that all peaks of TiO2 correspond to anatase crystalline phase. The BET surface area of the hollow spheres was about 22 m2g-1. The photocatalytic activity of the hollow anatase TiO2 was measured under UV light using γ-lindane as the target pollutant and was compared to commercially available TiO2.
The Effects of Alkali Silica Reaction (ASR) towards Fly Ash Based Geopolymer Concrete
Authors: Abd. Razak Siti Nooriza , Nuruddin Muhd. Fadhil
Published: November 2014

Alkali Silica Reaction (ASR) is a physiochemical reaction which affects the strength and durability of concrete. ASR occurs due to a chemical reaction between alkali oxides presents in the cement paste and reactive silica in aggregate. This reaction could lead to the volume expansion, cracking, loss of strength and potential failure of the concrete. This research aimed to investigate the potential alkali silica reactivity on geopolymer concrete. Specimens were prepared using Class F fly ash as binder while sodium hydroxide and sodium silicate as alkaline activators. ASTM C1260 was adopted to determine potential alkali silica reactivity by measuring the length change of mortar bar as well as the decrease in compressive strength test. Results show that fly ash based geopolymer concrete is less vulnerable to ASR as the expansion of mortar bar is below the threshold of ASTM standard limit which is 0.10% of expansion. This test ensures that the durability of geopolymer concrete is excellent and can withstand a long life span.
Effects of Helix Angle on Cutting Performance for Machining Thin-Wall Aerospace Monolithic Component
Authors: Mohd Hadzley Abu Bakar , Nurul Fatin Mohamad Raffi , Izamshah Raja , Siti Sarah Ahmad , Kasim Mohd Shahir , Ali Mohd Amran , Sulaiman Mohd Amri
Published: November 2014

The thin-walled component is mostly used in the aerospace industry. During machining the thin-walled components, deflection of wall occurs and causes the surface dimensional error. This paper focuses on the effect of end mill helix angle on the surface dimensional error and surface roughness when machining thin wall structure. End mills uncoated carbide were fabricated with a difference helix angle which are 25°, 30°, 35°, 40° and 45°. The results show, helix angle 35° produce smaller surface dimensional error and smoothest followed by 40°, 45°, 30° and 25°. The smaller helix angle provided high cutting force that causes more surface dimensional error due to chatter and reduction of contact time when then end mill engage with the workpiece material. Results from this research help to guide the machinist to machine thin-wall component with the right cutting tool.
Effect of Shear Rate on Characteristics, Performance and Morphology of Polysulfone Blend Membranes
Authors: Ali Asmadi , Yunus Rosli Mohd , Awang Mohamad , Johari Anwar , Mat Ramli
Published: November 2014

Rheological factor such as shear rate during membrane fabrication process has an effect on properties, structures and performance of membranes. Flat sheet asymmetric PSf/CAP blend membranes were prepared using an automatic casting machine at different shear rates in the range of 42.0 to 201.0 s-1. Results showed that increasing the shear rate from 42.0 to105 s-1 has increased the molecular orientation and thickness which then reduces the water content, porosity and pure water flux of PSf/CAP blend membranes. However, further increasing the shear rate beyond 105 s-1has resulted in an increase in the water content of PSf/CAP blend membranes.
Preparation and Properties of Silica Inverse Opal via Self-Assembly
Authors: Kassim Syara , Padmanabhan S. , McGrath J. , Pemble M.E.
Published: November 2014

The bottom-up colloidal synthesis of photonic band gap (PBG) materials or photonic crystals (PC) has attracted considerable interest as compared to so-called top-down lithographic approaches due to the simple processing steps involved and the prospect of the economically viable production of complex 3-dimensional optical materials from simple colloidal particles. To date self-assembly techniques constitute the most popular approach to fabricate 3D photonic crystals from colloidal particle suspensions. Based on the natural tendency of monodisperse colloidal particles to organise into ordered arrays, this method represent the best option due to the ease of fabrication, ability to produce larger area samples and cost. Here we report on the fabrication of long range three-dimensional (3D) ordered poly (methyl methacrylate) (PMMA)-silica PC structures and the subsequent fabrication of robust silica inverse opals using self-assembly methods. The optical properties of these materials are described and discussed in terms of potential applications of these materials.
Effect of Concentration and Time Factors on Carbon Nanofiber Supported Iron Catalyst Preparation by Incipient Wetness
Authors: van Thien Duc Nguyen , Sufian Suriati , Mansor Nurlidia , Yahya Noorhana
Published: November 2014

This paper discusses the influence of residence time and iron concentration factors on the impregnation yield for preparation of the carbon nanofiber supported iron material by incipient wetness impregnation. The samples were characterized by nitrogen physisorption, thermogravimetric analysis and electron spectroscopy techniques. The technique of effective impregnation was studied by atomic adsorption spectrophotometry. The results show that the morphology of the iron was distributed and well supported and the size of iron was in a wide range of 1μm to less than 2nm. The impregnation yield has been achieved 78% for 3 hours of residence time of 3%wt Fe/CNF sample with surface area of 102.292 m2/g.
Development of Fly Ash Based Geopolymer as Erosion Mitigation Coating
Authors: Yusof Noor Hafizah Ramli , Hamidi Rashidah Mohammed , Man Zakaria , Azizli Khairun Azizi , Nuruddin Mohd Fadhil
Published: November 2014

Loss of durability of concrete materials in sewage and chemical treatment facilities exposed to acidic environments is a key issue that affects the life cycle performance. Applications of organic coating such as epoxy and acrylic usually covers the concrete surface by physical addition normally failed to act as an effective coating due to debonding when the organic coating absorbs water. In this work, geopolymer was used as alternative material for concrete coating. Preparation of geopolymer involved fly ash, a materials containing high aluminosilicate and calcium mixed with various concentrations (6, 8 and 12M) of sodium hydroxide (NaOH). Subsequently, all samples were tested and analysed through compressive strength test and gel time. Geopolymers synthesised from 12M NaOH concentration exhibited high compressive strength and low gel time, hence was chosen as a coating for the concretes for the erosion evaluation. Results show that, concretes coated with geopolymers yielded low percentage of mass loss compared to the uncoated concretes. This suggest that geopolymers has high potential to be used as erosion mitigation coating to prevent the concretes from degrading due to the acidic environment.
Applicability of Alumina Nanofluid in Direct Absorption Solar Collectors
Authors: Sajid M.H. , Said Z. , Saidur Rahman , Mohd Sabri Mohd Faizul
Published: November 2014

Alumina nanofluid has unique thermo-physical properties which make it appreciable as thermal fluid, but its high extinction coefficient is not significant enough for making it a good solar irradiation absorber. The investigation was conducted on 0.05% v/v water-based alumina nanofluid and results showed that the nanofluid is able to attenuate approximately 50% of solar energy irradiated on the earth surface. Enhancement in absorption coefficient is found very little to increase absorptivity of basefluid using Rayleigh approach. It is found that the scattering coefficient of alumina is dominating absorption coefficient. Although high value of extinction coefficient is observed as usual, scattering is found responsible for this high extinction. The Rayleigh approach cannot explain the optical behaviour of the nanofluid and dominating scattering behaviour points toward alumina nanofluids’ weak capability as radiation absorber.
Determination of Dielectric Properties of Bismuth Titanate (BiT) Ceramic Material for WiMAX/WLAN Antenna
Authors: Hoon Wee Fwen , Abd Malek Mohd. Fareq , Seng Lee Yeng , Zahid Lyana , Fang Liew Hui
Published: November 2014

The utilization of Bismuth Titanate (BiT) as a ceramic material on an antenna has been investigated. The BiT ceramic material is of interest for a range of Wireless Local Area Network (WLAN) IEEE 802.11 b/g and Worldwide Interoperability for Microwave Access (WiMAX) IEEE 802.16 application, which covers the range of 2.3 GHz to 2.5 GHz. The BiT ceramic material had been tested to own a high dielectric constant of εr= 15 that is able to miniaturize an antenna. There is a high demand nowadays on the miniature antenna for smaller devices. An experimental prototype at WiMAX/WLAN range was built and measured on its dielectric properties, especially the dielectric constant and dielectric loss of the prototype material.
An Experimental on Honeycomb Core in the Axial Direction under the Quasi-Static Loading
Authors: bin Pokaad Alif Zulfakar , bin Said Md Radzai , bin Ahmad Fauzi , bin Kamaruddin Mohd Nazeri
Published: November 2014

This paper focuses on the quasi-static response of the aluminum honeycomb core based on an experimental work. The load-compression and energy absorb characteristics of the out-of-plane aluminium honeycomb core are studied for three varieties of the core cell sizes which are 0.01905, 0.0127 and 0.00635 m. The crushing tests were conducted on the Instron machine with a displacement control of 5 mm/min. The initial part in the load-displacement graph shows linear elastic characteristic, followed by a non-linear elastic-plastic regime before it collapses. Based on the observation, the cell sized 0.01905 m shows the global buckling collapse, but the cell sized 0.0127 and 0.00635 m collapse as progressive buckling mode. The cell size 0.00635 m shows highest energy absorption due to it has the highest density and it collapses like the progressive buckling mode compared with the others specimen.
Effect of Varying Inflow Reynolds Number on Pressure Recovery and Flow Uniformity of 3-D Turning Diffuser
Authors: Nordin Normayati , Abdul Karim Zainal Ambri , Othman Safiah , Raghavan Vijay R.
Published: November 2014

Various diffuser types characterized by the geometry are introduced in the flow line to recover the energy. A 3-D turning diffuser is a type of diffuser that its cross-section diffuses in all 3 directions of axes, i.e. x, y and z. In terms of applicability, a 3-D turning diffuser offers compactness and more outlet-inlet configurations over a 2-D turning diffuser. However, the flow within a 3-D turning diffuser is expected to be more complex which susceptible to excessive losses. As yet there is no established guideline that can be referred to choose a 3-D turning diffuser with an optimum performance. This paper aims to investigate the effects of varying inflow Reynolds number (Rein) on the performance of 3-D turning diffuser with 90o angle of turn. The outlet pressure recovery (Cp) and flow uniformity (σu) of 3-D turning diffuser with an area ratio (AR = 2.16) and outlet-inlet configurations (W2/W1 = 1.44, X2/X1 = 1.5), operated at inflow Reynolds number of Rein = 5.786E+04 - 1.775E+05 have been experimentally tested. The experimental rig was developed by incorporating several features of low subsonic wind tunnel. This was mainly to produce a perfect fully developed and uniform flow entering diffuser. Particle image velocimetry (PIV) was used to examine the flow quality, and a digital manometer was used to measure the average static pressure of the inlet and outlet of turning diffuser. There is a promising improvement in terms of flow uniformity when a 3-D turning diffuser is used instead of a 2-D turning diffuser with the same AR. An unexpected trend found with a drop of pressure recovery at maximum operating condition of Rein = 1.775E+05 shall require further investigations. The results obtained from this study will be in future used to validate the numerical codes. Upon successful validation, several other configurations will be numerically tested in order to establish the guidelines in the form of mathematical models.
Drying of Oil Palm Fronds Using Concentrated Solar Thermal Power
Authors: Sulaiman Shaharin Anwar , Taha Farid Fawzy Fathy
Published: November 2014

Malaysia has great potential for biomass stock. The fact that oil palm fronds contain high moisture content makes it unsuitable to be used directly as a biomass fuel neither for direct combustion nor gasification. Conventional and costly drying methods make the fronds a non-attractive fuel especially in humid tropical countries, where sources of biomass is abundant. A new solar dryer design is proposed that utilizes concentrated solar thermal energy for drying oil palm fronds. A prototype for the dryer has been fabricated and tested. The system’s target is to maximize the thermal energy received by the system and to minimize energy loss out of the system. Experiments were performed on samples of oil palm fronds at a drying temperature not exceeding 110°C; in order not to affect the organic material of the biomass. Results were compared with another experiment performed at the same temperature. An electric oven was used for drying. The samples were completely dried using the proposed system for 6.5 hours, compared to 10.5 hours by using the electric oven. The proposed system achieved an average drying rate of 4.75 g/hr compared to an average drying rate of 2.83 g/hr using the electric oven. The efficiency of the dryer was calculated to be 55.4%, implying good potential of the proposed system.
Preliminary Study of Oil Palm Frond Briquette as Biomass Fuel for Gasification
Authors: Zaidi Moni Mohamad Nazmi , Sulaiman Shaharin Anwar
Published: November 2014

Oil palm frond is one of the most potential biomass solid fuel sources for heat and power generation. Processing of oil palm frond into solid fuel created underutilized and neglected residues in the forms of fiber, grains and sawdust. Fuel briquettes of 10.5 cm in diameter and 2.5 cm in thickness were formed from the residues using a hand press briquette maker and tested as solid fuel for gasification. With a specific density of 40 kg/m3 and an equilibrium moisture content of 12±1.5% by dry basis, the briquettes were found to pass extensive drop tests and were able to produce syngas consisting of 8.1% CO, 11% CO2, 2.1% H2 and 0.5% CH4 through gasification. Successful syngas ignitions were obtained from the updraft gasification of the briquettes, showing the briquettes potential as a prospective solid fuel for heat and power generation.
Activity of Copper and Nickel Loaded on HZSM-5Zeolite Based Catalyst for Steam Reforming of Glycerol to Hydrogen
Authors: Yun Hafizah Abdul Halim , Mat Ramli , Tuan Abdullah Tuan Amran , Mohamed Mahadhir , Asmadi Ali Anwar Johariand
Published: November 2014

The study focuses on hydrogen production via glycerol steam reforming over copper and nickel loaded on HZSM-5 zeolite based catalyst. The catalysts were prepared by using different loading amount of copper (0-10wt%) and nickel (0-10wt%) on HZSM-5 zeolite catalysts through wet impregnation method and was characterized by X-Ray Diffraction (XRD). The performances of catalysts were evaluated in terms of glycerol conversion and hydrogen production at 500°C using 6:1 of water to glycerol molar ratio (WGMR) in a tubular fixed bed reactor. All the catalysts had achieved more than 85% of glycerol conversion except that of 5%Cu loaded on HZSM-5 catalyst. The addition of nickel into 5% Cu/HZSM-5 catalyst had increased the hydrogen yield. Similar trend was observed when copper was added into Ni/HZSM-5 catalyst but using copper loaded on HZSM-5 alone was unable to produce hydrogen compared to using nickel catalyst alone. It showed that copper acted as a promoter for hydrogen production. It was established that a 5wt% of Cu with 10wt% of Ni loaded on HZSM-5 catalyst showed significant improvement in terms of hydrogen yield and gaseous product compositions at selected operating conditions.
Investigation of Photocatalytic Activity of TiO2-PANi Nanocomposites
Authors: Che Ramli Zatil Amali , Wan Isahak Wan Nor Roslam , Yarmo Mohd Ambar , Asim Nilofar
Published: November 2014

In this paper the photocatalytic activity of TiO2-PANi nanocomposites prepared using two different In-situ polymerization methods have been investigated. The same pressure, temperature, precursors, mole ratio, and solvent have been employed for preparation of nanocomposites. The synthesized nanocomposites were characterized by FESEM, XRD and FTIR. Results revealed the successful preparation of TiO2- PANI nanocomposites. TiO2-PANi nanocomposite synthesized using method 2 showed very well dispersed TiO2 nanoparticles on the surface of PANi. There is no agglomeration of TiO2 nanoparticles in PANi matrix. The photocatalytic activities of nanocomposites were evaluated by using photo degradation of Methylene Blue (MB) in aqueous solution under UV irradiation. These nanocomposites exhibit much higher photocatalytic activity compared with TiO2.
Gasification of Empty Fruit Bunch Briquettes in a Fixed Bed Tubular Reactor for Hydrogen Production
Authors: Nyakuma Bemgba Bevan , Mazangi Mojtaba , Tuan Abdullah Tuan Amran , Johari Anwar , Ahmad Arshad , Oladokun Olagoke
Published: November 2014

The gasification of EFB briquette was investigated in a fixed bed tubular reactor to examine the effects of temperature on gas composition, heating value and cold conversion efficiency.The resultsrevealedthat H2 gas composition increased from 17.17 mol. % to 29.67 mol. % with increasing temperature from 600°C to 700°C at an equivalence ratio (ER) of 0.4. The heating value (HHV) of the producer gas increased from 6.18 MJ/Nm3 to 7.64 MJ/Nm3 and cold gas efficiency increased from 35.19% to 43.50% with increasing temperature during gasification. However, carbon conversion efficiency increased only marginally from 31.85% to 32.84% while a significant quantity of char (~ 21%) was produced per unit mass of EFB briquette. The results indicate that higher temperatures are required to increase the overall efficiency of EFB briquette gasification in a fixed bed tubular reactor.
Performance Evaluation of Dye Sensitized Solar Cell for Varying TiO2 Thicknesses
Authors: Fitra Muhammad , Gomesh Nair , Irwanto Muhammad , Yusoff Mohd Irwan , Mariun Norman
Published: November 2014

A dye-sensitized solar cell with a dimension of 6 x 2 cm is fabricated with variation Titanium Dioxide, TiO2 thickness of 40 μm, 80 μm and 120 μm by smearing it on an Indium Tin Oxide, ITO coated glass. It was then tested under the average solar irradiance and temperature of 693.69 W/m2, 44.4 °C respectively. Based on investigation it was found that TiO2 of 40 μm produces an open voltage circuit of 0.21V, Short circuit current of 121.28 μA, and efficiency (η) of 9.78% while the 80 μm produces open voltage circuit of 0.16 V, short circuit current of 69.89μA and efficiency (η) of 2.66%, and TiO2 layer with thickness of 120 μm produces open voltage circuit of 0.00063 V short circuit current of 0 mA, efficiency (η) of 0%, and from these results, it shows that the best charge generation is from the thinner TiO2 thickness layer which is the 40 μm compare to other size.
Three-Phase Supply for Solar Application with MPPT Controller
Authors: bin Shariff Mohamad Findyrul , Lada Musa Yusup , Bugis Ismadi , bin Ab Ghani Sharin
Published: November 2014

This paper presents the implementation of three-phase sinusoidal inverter powered from a solar PV, 12V Lead-acid battery, and MPPT controller. Considering the Malaysia weather, it is in general the weather change very fast from the sunny clear sky up to the very thick cloud. Hence, the perturb and observe (P&O) control scheme is designed to crop solar energy in the most efficient manner and store the energy to the battery. To convert the output from solar or battery into high quality three-phase sinusoidal alternating current (AC) voltage, low resistive MOSFETs switches inverter is used by adopting Sinusoidal Pulse Width Modulation Technique (SPWM). The frequency of the AC voltage can be adjusted from 30 up to 65 Hz with constant voltage over frequency (V/F) ratio. It is expected that the device can be used as stand-alone electrical supply for dedicated devices such as agricultural water pumping, drug-cold-storage in remote village, cold storage for fisherman, self-powered and unmanned water pump, forest security and surveillance device, etc. Furthermore, the device is also equipped with status display, over current and excessive charging protection, and low power warnings.
V-Bend Die Forming Performance of Oil Palm Fiber Composite
Authors: Dhar Malingam Sivakumar , bin Che Mahzan Muhammad Ammar , bin Said Md Radzai , Rivai Ahmad , Nordin Mohd Nur Azmi , Selamat Mohd Zulkefli , Sivaraos Sivaraos
Published: November 2014

Composite materials have steadily gained recognition worldwide for its uses in various sectors such as aerospace, infrastructures and automotive industries. In stamp forming of V-bend die, the most sensitive feature is elastic recovery during unloading called spring-back. This phenomenon will affect bend angle and bend curvature. This research studies the effects of tool radius, feed rate, temperature and weight ratio of fiber to Polypropylene on the spring-back of palm fiber composite. Analyzed results obtained from Design of Experiment (DOE) shows temperature, fiber composition followed by feed rate gives significant effect towards spring-back. The suggested temperature, fiber composition and feed rate to get the smallest spring-back angle in the current study are 150°C, 30wt% and 500mm/min.
The Potential Energy of Plastic Solid Waste as Alternative Fuel for Power Plants in Indonesia
Authors: Anshar Muhammad , Ani Farid Nasir , Kader Ab Saman
Published: November 2014

Studies on the potential of plastic solid waste (PSW) as a fuel supplement for power plant was conducted to determine the potential energy and economic value in Indonesia. In analyzing the potential energy and economic value of PSW, 15 cities provinces having municipal solid waste production of greater than 1,000 tons/day were selected. The study showed that with the total potential of PSW of around 693 tons/day, the electrical energy potential available is around 7,987 MWh/day. The PSW equivalent with coal is approximately 1,065 tons/day, and its equivalent to the oil is around 593 tons/day. In conclusion, the PSW is an environmental pollution material but have the energy and economic potential to be used as a fuel supplement for the power plants. Thereby, it can save the use of coal by means co-combustion with PSW and at the same time be able overcome the environmental problems caused by pollution PSW in Indonesia.