bluuebunny/crossref_metadata_2025 huggingface dataset:
Superiority of Superheated Steam Flooding in Development of High Water-Cut Heavy Oil Reservoir
Authors: Xu An Zhu , Mu Long Xin , Wu Xiang Hong , Fan Zi Fei , Zhao Lun
Published: December 2012

The dryness of superheated steam is 100% and it exists in the form of pure steam whose properties are like ideal gas. When the steam has a large degree of superheat, it may take a relatively long time to cool, during which time the steam is releasing very little energy and transmitted long distances. The heating radius of superheated steam in the formation is 5-10m larger than saturated steam. In the heating area of superheated steam, the comprehensive effects by superheated steam (crude oil viscosity reduction, improved flow environment, changes in rock wettability and improved oil displacement efficiency, etc.) is much higher than that of saturated steam. Superheated steam stimulation in Kenkyak high water cut heavy oil reservoir pilot test results showed that the average daily oil production of single well by superheated steam stimulation was 2-4 times than that of saturated steam stimulation. Superheated steam is more effective to heat water-invaded oil reservoir than saturated steam.
Horizontal Axis Wind Turbine Numerical Simulation of Two Dimensional Angle of Attack
Authors: Yu Jing Mei , Yu Yan Hong , Liu Pan Pan
Published: December 2012

wind power is the most effective form of wind energy utilization, modern large-scale wind turbine with horizontal axis wind mainly. Horizontal axis wind turbine aerodynamic performance calculation of the wind turbine aerodynamics research hot spot, is a wind turbine aerodynamic optimization design and calculation of critical load. Horizontal axis wind turbine airfoil aerodynamic performance of the wind turbine operation characteristics and life plays a decisive role". Using Fluent software on the horizontal axis wind turbine numerical simulation, analysis of the United States of America S809NREL airfoil aerodynamic characteristics of different angles of attack numerical simulation, analyzes the different angles of attack in the vicinity of the pressure, velocity distribution. By solving the two-dimensional unsteady, compressible N-S equations for the calculation of wind turbine airfoil S809used the characteristics of flow around. N-S equation in body-fitted coordinate system is given, with the Poisson equation method to generate the C grid.
Key Parts Structure Optimum Design of Plow
Authors: Zhu Bo , Li Hui
Published: December 2012

Our country has abundant coal resources, thin seam can reserves 20% of all can be occupied. But , with adverse circumstances, thin coal seam mining has not yet been fully realized automation. Plough is a kind of mining equipment with shallow-frustum, Low mining height, multi circulation.Its simple structure in thin coal seam mining is a unique advantage. Along with the plough development to high-powered, high speed to dig, automation direction, and with its reliable performance problems appear more prominent, it is badly in need of further research and discussion. In order to improve the reliability of plough, expand the scope of use plough, this paper applied the method of virtual prototype of the plough structure strength analysis. Taking a coal company designed BT plough as project object, the joint simulation environment is been established by Pro/E,ANSYS and ADAMS.by using corresponding modal interface technology. At last rigid-flexible coupled model has been formed in ADAM.
Application of VOF Interfacial Tracking Model to Condensation Heat Transfer
Authors: Zhang Jun Xia , Xu Xiao Lin
Published: December 2012

Condensation heat transfer used to the condenser as an important way of heat transfer is a phenomenon that involves flowing and heat and mass transfer of both gas and liquid phases. Thus, the development of its numerical prediction helps to the design of the condenser. At the present work, a VOF model was used to numerically simulate condensation heat transfer in a V-shape tube, obtaining volume fraction of vapor, location of liquid film and parameters of heat transfer. Results show that the VOF model may predict flow pattern of condensation and mass flux of condensation of vapor on the liquid film well. From computations, mass flux of condensation of vapor on the liquid film increases along vapor flowing, however, it tends to steady at the back part of the condenser tube. Flow pattern of condensation develops from annular flow at the inlet of the condenser tube to stratified flow, finally to plug flow at its back part. Velocity decreases along the tube length.
Dynamic Analysis on the Longitudinal Roadheader’s Cutting System
Authors: Wei Xiao Hua , Xie Miao
Published: December 2012

The cutting system of the longitudinal roadheader is simplified to get the physical model. And the dynamic model is obtained on the basis of that. Then the simulating model is established by using Matlab/Simulink. Furthermore, the relative technical variants are analyzed and determined. Computer analysis is performed by setting some parameters which conform to the actual working conditions.
Crash Safety and Light Quality of Automobile Bumper Made of Tube Filled with Foam Aluminum
Authors: Yu Ying Hua , Tan Hai Nan , Yang Kun , Wang Ping Ping
Published: December 2012

Taking hollow steel tube bumper as the prototype, the structure of steel bumper filled with foam aluminum was simplified preliminary. Then the finite element deformations of two bumper structures were analyzed in the same collision condition. And the quality of two bumper structures were calculated and compared. The results show that automobile bumper made of metal tube filled with foam aluminum can improve the cash safety and reduce the quality of the car significantly. This research provides a new way to improve vehicle safety, energy conservation and environmental protection.
Study on Mine Hoist Driven by PMSM of Low Voltage and Multi-Branch
Authors: Zhang Bing Yi , Li Qing Xu , Feng Gui Hong , Wang Bing , Sun Han Guang
Published: December 2012

As a set of typical mechanical and electrical integration equipment, mine hoist plays an important part in mineral mining industry known as the "mine throat". Traditional mine hoist mainly has the winding induction motor drive system, generator-dc machines and dc motor powered by the thyristor rectifier system. However, with the growing requirements of modern large mine hoist on hoisting tonnage, control performance, safety, reliability and the ratio of performance to price, the limitation of the traditional drive system emerges. If the permanent magnet synchronous motor(PMSM) is used to driven the heavy load, the speed reducer can be canceled. Thus, the performance of the system and control characteristic can be improved greatly. According to the status in this field above, this article brought forward a type of mine hoist with multi-rope friction driven by PMSM. A kind of multi branch control mode is adopted. Out of the actual needs of the project, a rated power 1300 kW of multi-rope friction mine hoist is designed and manufactured. Loss and heating of high power PMSM is studied. A kind of inner circulation air-cooled system is worked out. And good cooling effect is achieved.
Review of the Development of Dry Coal Preparation Theory and Equipment
Authors: Dong Hai Lin , Liu Chu Sheng , Zhao Yue Min , Zhao La La
Published: December 2012

Dry efficient separation of moist fine coal is an important part of the development of clean coal technology. This paper reviewed the research situation of the dry screening theory for moist fine coal and summarized the development status of dry screening equipment. The results show that the moist fine materials have complex physical properties and the theory of dry deep screening needs further improved. Flip-flow screen is a kind of screening equipment with wide application prospects, which can well solve the dry deep screening problem of the moist fine materials.
Forecast of Blasting Fragmentation Distribution Based on BP Neural Network
Authors: Gao Hong , Fu Zhi Liang
Published: December 2012

The influence factors of rock blasting fragmentation distribution are analyzed, 10 main influence factors are selected from these. Using the MATLAB BP neural network model system to analyze blasting fragmentation distribution of +860 level face at Yi Chun tantalum-niobium mine, successfully predicted the blasting fragmentation distribution, it is favorable to design the blasting parameters and industrial production.
Control System Design of the Vehicle Mounted Hammer Source Based on PLC
Authors: Wang Hong Yan , Xiao Wen Sheng , Lin Xiu Juan , Wang Xian Feng
Published: December 2012

Considering the pollution on the environment using dynamite source in oil and gas exploration, harm and damage to people and building, the vehicle mounted hammer source which can replace dynamite source is presented. This paper describes briefly the basic structure and working principles of the vehicle mounted hammer source. A typical pneumatic circuit is researched and designed. And the pneumatic circuit is designed with the powerful functions of PLC, the hardware and software design are introduced. The system has advantages of strong striking force, high velocity, small gas consumption, simple structure and convenient control.
Design and Analysis of the Six Systems of Refuge Chamber in Coal Mine
Authors: Wang Yu Qing , Chen Xiao Jing , Li Zhi Guo , Deng Le
Published: December 2012

The refuge chamber is an important part of the emergency refuge system in coal mine. This paper mainly introduced the design ideas of underground layout, structure, six systems of disaster prevention system, life support system, life support and emergency system, power supply system, communication system and external disaster information detection system in refuge chamber. This provides a scientific design basis for constructing refuge chamber in the coal mine.
Following Straightly Control Strategy and Testing for Split Platform in Roadway
Authors: Zhao Jing Yi , Chen Feng Lei , Guo Rui
Published: December 2012

On the basis of two pilots operating the split truck in the roadway, study control strategy of the single-pilot operating powering vehicle and flatbed walking and following straight; establish the kinematic model of the control method and field test verification; detect angles of the rod and powering vehicle、flatbed vehicle; improve the control performance of the truck, supply the theoretical and practical basis for similar products, and further corner’s following.
Design of a Type of Handling Robot
Authors: Li Ze Lun , Huang Zhi Cheng , Deng Xian Ling
Published: December 2012

Designed a handling robot system which can meet the requirements of teaching and experiments. Completed the design of body structure, the hardware and software system of robot. On the one hand the DC motor is used to power to the robot base by the remote through the wireless module, on the other hand the steering is manipulated through the microcontroller I / O port, and it make the robot to be free to operate and precise positioning of the manipulator.
The Structure Design of Slit-Charge for Directional Fracture Controlled Blasting in Stone Drifting
Authors: Yang Ren Shu , Gao Xiang Tao , Liu Guo Qing , Li Xiao , Hao Deng Yun
Published: December 2012

Slit-charge for directional fracture controlled blasting technology has demonstrated the clear superiority in stone drifting in coal mines. However, the slit-charge has not yet been molded products, which limited its application to further promotion. Structural parameter optimization for slit-charge using orthogonal experimental design method was carried out. The slit-charge blasting in Lead column performed, the slit-charge blasting primary and secondary influencing factors were obtained by using range analysis; Range analysis methods were applied to analyze the sensitivity of these factors and coupling influences. Structural parameters of slit-charge were determined according to effect curves. This product is easy to use and significant effect in the field. All of half blast-hole trace ratios are more than 90%, the driving speed could be highly increased．Contour shape of roadway is in good condition to avoid rockfalls and rockslides. Overbreak can be costly. Theoretical results are translated into technology, and technological achievements into products.
Control System Analysis of Hydrodynamic Retarder of Heavy Truck
Authors: Li Lin , Ma Wen Xing , Cai Wei , Chu Ya Xu , Song Jian Jun , Zhang Yan
Published: December 2012

In order to meet working requirements, the control system of hydrodynamic retarder of heavy truck should have the capability of rapid response and large flow. Based on the demands as above, a control system of hydrodynamic retarder was designed and simulated to obtain the dynamic characteristics of the control valve of oil-charge and oil-discharge. Finally, the time of oil-charge and oil-discharge of hydrodynamic retarder was computed and the results showed that the control system could meet the working requirements.
Automatic Connection of GPIB Communication Protocol for Manufacturing System
Authors: Choi Chel Rim , Jeong Hwa Young , Choi Hae Gill
Published: December 2012

Various types of communication were used in the factory. And the manufacturing system, machine, normally use GPIB communication due to their efficiency, cost, and high performance. However the GPIB protocol is different type by their manufacturing company. Therefore the system engineers often spend lots of time to setup and initialized their system for GPIB communication. In this paper, we proposed automatic connection module of GPIB communication for manufacturing system in their factory. The module can find their GPIB type and protocol, and access their communication efficiently. It also can reduce the system fault or communication jam when manufacturing system initialized setup process for GPIB and begin to interface between them.
Simulated Research for Effect of Mixer Shaft Speed on Flow Field in Mixing Machine
Authors: Kang Wen Long , Gu Xin Yue , Ma Mu Jia
Published: December 2012

Along with the rapid development of China's economy, the CFD technology has become an indispensable new technology in industrial production, and it plays an important role in the development of industry. Using computational fluid dynamics software called FLUENT. The investigation was carried out in a mixer, which its internal flow of the 3-d numerical simulation. The unstructured tetrahedron grid and unsteady multiphase turbulent calculation model were used to analyze the mixer internal fluid concentration, speed and turbulent kinetic parameters e.g., which produce changes and distributions with the different stirring shaft speed, and reveal the law of internal flow. Through the simulation result, can conclude that the numerical simulation method can truly reflect the interior complicated flow state of mixing machine, and can provide theory basis for the design and improvement of the mixing equipment.
Huge Forging Equipment Hydraulic System Dynamic Analysis
Authors: Xie Miao , Meng Jun , Xu Wen Xin , Dong Rong Bao , Wang Jian Liang
Published: December 2012

In order to optimize the dynamic characteristic of hydraulic system of large forging equipment. It based on the model of one company of a certain aero-engine hydraulic system of hydraulic hammer forging, analysis the composition and working principle of hydraulic systems. Using simulation software AMESim, simulate the model of hydraulic systems and by changing the system pressure, flow and effect of the hammer-head stroke to explore this kind of switching characteristics of forging equipment’s hydraulic system. The result shows that this kind of simulation models can reflect the working status of hydraulic hammer well, and provide a technical reference for analysis and tuning equipment that with similar to forging equipment.
Fault Diagnosis Expert System of Continuous Miner Hydraulic System
Authors: Li Xiao Huo , Tang Ren Peng , Sha Yong Dong , Bai Shuai Wi , Zhang Jing Hui
Published: December 2012

In order to fine working states of a continuous miner hydraulic system, diagnose quickly and effectively its faults, reduce failure rate, save maintenance time and improve the reliability and productivity of a continuous miner, the GA-PSO hybrid optimization method of fuzzy neural network is used in fault diagnosis of a continuous miner hydraulic system in the paper, a intelligent fault diagnosis expert system of a hydraulic system is designed by means of taking VC 6.0 as the programming platform, using SQL SERVER 2000 as database, embedding MATLAB7.1 in the internal. The system is simple in man-machine interface and good in man-machine conversation, capable of analyzing accurately and judging properly failures of a continuous miner hydraulic system.
Dynamic Characteristic Analysis on Hydraulic Control System for Cutting System of Longitudinal Roadheaders
Authors: Wei Xiao Hua , Xie Miao
Published: December 2012

Dynamic characteristics of the hydraulic control system for the cutting system of roadheaders are very important for analyzing the working performance. This paper supplies the modularization design method for hydraulic control system of cutting system of roadheaders. It utilizes the Matlab/Simulink to establish the mathematical model for each hydraulic components of the cutting system. And the hydraulic control system model is simulated by Matlab/Simulink. It’s useful for predicting and optimize the dynamic response of the hydraulic control system.
Research on Wear Resistance of Mg2Si Reinforced Hypereutectic Al-Si Alloy Composite
Authors: Liu Zheng , Liu Xiao Mei
Published: December 2012

Mg2Si particle reinforced hypereutectic Al-Si composite was prepared by casting, and the microstructure and wear resistance of the composite were researched. The results indicated that the morphology of Mg2Si obviously changed with Mg2Si contents increasing, in which the morphology of Mg2Si in the composite had changed from polygon block to characters like and finally became coarse dendrite. There were effects of Mg2Si content and morphology on the wear resistance in the composite, which had the higher hardness and better wear resistance at the suitable Mg2Si content.
Comparison Analysis of Lower Temperature PCM on Phase Change Energy Storage Process at Different Models
Authors: Qiu Lin , Niu Run Ping , Yan Min
Published: December 2012

This article simulation studies the thermal Characteristics of a lower temperature phase change materials (PCMs) using in the building energy storage by two different models. In the process of phase change, liquid phase is used as two ways of heat exchange: pure heat conduction and natural convection, and we exploit CFD software to carry out numerical simulation. To compare and analyze under melt and solidification, the proportion of solid and liquid, the time of phase change, the interface of phase change and motion temperature image of liquid-region.
Preparation and Film-Substrate Stress Analysis of CVD Diamond Film Coating Tools
Authors: Zheng You Yi , Zhang Chun Lin , Xu Xing Xin
Published: December 2012

The diamond thin films was deposited by hot filament CVD method in the Cemented Carbide (YG6) substrate. The surface morphology and quality of the diamond film coating was detected by scanning electron microscopy and Raman spectrometer. The internal stress of the diamond thin films and Cemented Carbide substrate, exerted by load, was calculated by the method of finite element numerical analysis. The analysis result shows that the internal stress of the film is tensile stress. The maximum appear in the blade and the tip place, the stress distribution more evenly in the middle area of the film. The stress is a zonal distribution and reduced gradually from the matrix surface to bottom in the Cemented Carbide, the results of the finite element analysis can provide the reference for the other methods to determin the diamond film stress and improve the stress between the membrane and substrate.
Prepared for GaAs PHEMT Material
Authors: Li Yan Lei , Yang Rui Xia
Published: December 2012

In this paper, GaAs PHEMT samples are prepared by the method of molecular beam epitaxy (MBE), The optimal parameters are determined by studying the impact of the barrier layer thickness, spacer layer thickness, Al composition of the barrier layer and the spacer layer , the channel thickness and channel In composition on Ns and μn.
Finite Element Analysis Based on the CATIA Mine Car Engine Connecting Rod
Authors: Pu Zhi Xin , Yang Xin Yuan
Published: December 2012

Mining truck is a large-scale construction machinery,in many open-air mining process, it is the main transportation equipment, By CATIA modeling the mine car engine connecting rod , and use of CATIA's finite element analysis to analyse the linkage structure,calculate the load conditions.
Research on Nonlinear Dynamical Behaviors of Mine Hoist Transmission System under External Excitation
Authors: Jia Chao , Li Yan Shu , Wang Bo Hua , Zhao Shuang Shuang , Li Xue
Published: December 2012

For the research on dynamical behaviors of mine hoist transmission system under strong nonlinear condition, the dynamic equation with nonlinear stiffness, nonlinear damping and external excitation is established. With the method of modified Lindstedt-Poincare, the influence of system parameters on amplitude-frequency characteristic is analyzed. Last, the complex dynamical behaviors caused by the change of excitation amplitude is studied through numerical simulation, and the evolution process from stability to chaos is described by the use of bifurcation diagram, maximum Lyapunov index figure and Poincare section graph. This provides a theoretical basis for further research of mine hoist transmission system.
Gel Oxidation of Titanium for Biomedical Application
Authors: Abdullah Hasan Zuhudi , Koshy Pramod , Sorrell Charles C.
Published: December 2012

Sodium titanate gels have been formed on the surface of titanium metal using sodium hydroxide solution and then oxidised at 400° - 800°C. The reaction sequence for these processes with increasing temperature is Ti sodium titanate gel crystalline sodium titanate gel porous (top) and dense (bottom) anatase porous (top) and dense (bottom) rutile. These samples were subsequently soaked in simulated body fluid in order to study the precipitation of hydroxyapatite.
The Influence of Temperature on the Oxide Layer Formation of Aluminized Carbon Steel
Authors: Husain Hishamuddin H.J. , Daud Abdul Razak , Daud Muhamad , Anasyida Abu Seman , Yazid Hafizal
Published: December 2012

The growth of thin oxide layer due to the variation in temperature on the surface of aluminized carbon steel was investigated. Hot dip aluminizing of low carbon steel was carried out at 750 °C in a molten pure aluminum for 5 minutes. Aluminized samples were heat treated at 600 °C, 700 °C, 800 °C, and 900 °C for 1 hour. The formation of aluminum oxide layer was investigated in this study. Optical microscopy, Atomic Force Microscopy (AFM), SEM and EDAX were used in investigation. From the observation, the appearance of aluminum oxide layer increased with the increase in temperature. The result of EDAX analysis revealed the existence alumina phase. Surface roughness measurement showed increment with the increase in oxidation heat treatment temperature.
WO3-Polypyrrole Nanocomposite as Catalyst in Azelaic Acid Synthesis from Oleic Acid
Authors: Ghoreishi Khadijeh Beigom , Yarmo Mohd Ambar
Published: December 2012

Catalytic oxidation of oleic acid with ozone gas by using ozone-generator and solvent free medium in the presence of WO3-Polypyrrole (ppy) nanocomposite was studied. Azelaic acid (AA) and pelargonic acids (PA) are the major reaction products, however the percentage of AA production is significantly higher than PA. Experimental results concluded that tungsten oxide and tungten oxide on polypyrrole are suitable catalysts in terms of their selectivity and activity. Reaction is done in two steps within 90 minute, showing the reasonable promotion in selectivity to AA by using WO3-ppy catalyst system compared to reaction with WO3 as catalyst. WO3-ppy nanocomposite is prepared by sonication method and characterized by FT-IR, XRD, and FESEM analysis. The products of ozonolysis are identified by GC-FID and GC-MS for measuring selectivity and reactivity as well.
XRD and EDXRF Analysis of Anatase Nano-TiO2 Synthesized from Mineral Precursors
Authors: Mahdi E.M. , Abdul Shukor Mohd Hamdi , Meor Yusoff Meor Sulaiman , Wilfred Paulus
Published: December 2012

This work details the characterization of anatase nanoTiO2 particles synthesized from Malaysian mineral precursors using the XRD and EDXRF. The properties that were analyzed were its crystallite sizes, relative crystallinity, phases, and chemical composition. It was determined that the crystallite size was quite small (15.6 nm), although the crystallinity of the sample is relatively low. The anatase phase seems to be dominant (100%), although in some cases when the processing parameters were changed or heat treatment were conducted, the existence of rutile is detected. The chemical composition showed that TiO2 is the majority compound in the sample (~96%), although some metallic and non-metallic impurities are present (Zr, Nb, and S). It is concluded that Malaysian mineral precursors are capable of producing relatively high quality nanoTiO2.
The Effect of MgO Dopant on the Dielectric Properties of CaCu3Ti4O12 Ceramics
Authors: Ab Rahman Mohd Fariz , Mohamed Julie Juliewatty , Ain Mohd Fadzil , Hutagalung Sabar Derita
Published: December 2012

The properties of undoped and Mg-doped CaCu3Ti4O12 (CCTO) ceramics have been studied. The samples were calcined at 900°C for 12 hours, and sintered at 1030°C for 10 hours. X-ray diffraction analysis on calcined samples shown the formation of CCTO phase with trace of secondary phases meanwhile completed formation of CCTO single phase obtained for sintered pellets. The peak positions of Mg-doped CCTO were slightly left-shifted from the undoped CCTO, attributed to the lattice expansion. Scanning electron microscopy analysis showed that the grains size becomes larger with the increment of dopant amount. Enhanced dielectric constant was observed in the Ca1-xMgxCu3Ti4O12 ceramics with x = 0.05 for the frequency range from 1 MHz to 1 GHz. The dielectric loss seem to be at lowest value when Ca1-xMgxCu3Ti4O12 ceramics with x = 0.10 at the same frequency range. The results indicate that Mg ions have effectively changed the properties of CCTO.
Characterization of Potential Used Rubber Seed Coat Waste for the Removal of Remazol Brilliant Blue R Reactive Dye
Authors: Idris Mohd Nazri , Ahmad Zainal Arifin , Ahmad Mohd Azmier
Published: December 2012

In the present work, activated carbon was prepared from rubber seed coat by physicochemical activation for the removal of Remazol Brilliant Blue R (RBBR) dye from aqueous solution. The effects of dye initial concentration, contact time, solution temperature and pH on RBBR adsorption onto rubber seed coat based activated carbon (RSCAC) were investigated. The adsorption uptake was found to increase with increase in initial dye concentration and contact time. Change in temperature and pH also played an important role to RBBR adsorption capability. Study showed that rubber seed coat is suitable to be used as activated carbon precursor.
Luminescence of SrAl2O4:Eu2+, Dy3+ Ceramics Synthesized at Different Firing Condition
Authors: Nazida A. Nor , Fauzi M.N Ahmad , Nazarov M. , Azizan A. , Rizal K. Shah
Published: December 2012

The green SrAl2O4:Eu2+, Dy3+ phosphor is a well-known persistent material for a wide region of applications such as lighting, traffic signs, interior decoration and medical application. Double activated SrAl2O4:Eu2+, Dy3+ with improved properties has been synthesized through solid state route at different firing atmospheres (reduction, vacuum, oxygen and CO2 wet gas) and heating times (1 h to 8 h). At the beginning the powders were heat treated for 2 h with a heating rate of 10°C/min. The phosphor prepared at different firing atmospheres and heating times exhibited a different wavelength and intensity of PL spectra. The emission intensity becomes stronger as the heating times increases from 1 h to 4 h. The difference found from these spectra maxima is rationalized based on the presence of intermediate phases and also on the diffusion activities of activator and co-activator in the host matrices.
Tin Oxide Doped on Activated Dolomites as Efficient Catalyst for Biodiesel Production
Authors: Nur Z.A. Shajaratun , Taufiq-Yap Y.H. , Hussein M.Z.
Published: December 2012

Activated dolomite (AD), was investigated as a promising heterogeneous catalyst for the production of biodiesel. SnO2 doped on activated dolomites catalyst (DSN) was synthesized through wet impregnation method and calcined at 500 °C for 3 h in air. The catalyst was then applied on biodiesel production via transesterification of palm cooking oil with methanol for required conditions (various time, oil to methanol ratio and amount of catalyst). X-ray Diffractometer (XRD), Brunauer-Emmet-Teller (BET) surface area, X-ray Fluoresence (XRF), Scanning Electron Microscopy (SEM) and Temperature Program Desorption (TPD) analysis were used to characterize the properties of the catalysts. Results showed that conversion of biodiesel by using DSN was higher (99.9 %) with lower optimum conditions i.e. 1:15 methanol to oil molar ratio, 1 wt. % of catalyst amount and reaction time of 6 h at 65 °C compared to AD (98.34 %) under higher conditions.
Effect of Nickel on Titanium Carbide Synthesized via Tungsten Inert Gas (TIG) Method
Authors: Salim Sharifah Aishah Syed , Mohamed Julie Juliewatty , Ahmad Zainal Arifin , Ahmad Zainal Arifin
Published: December 2012

Numerous methods have been used to produce high purity TiC. There is no previous study has been reported on the formation using single elemental powders of Titanium (Ti) and Carbon (C) with addition Nickel (Ni) by tungsten inert gas (TIG) weld method. In this work, TiC was synthesized via TIG method by arc melting elemental powder mixture of Ti and C at ~5 second (s) and 80 ampere (A). The effect Ni contents on TiC formation was investigated. The mixed raw material was ball milled for 24 hours followed by synthesis via TIG method. The arced samples were characterized by X-ray diffraction (XRD) and Scanning electron microscope (SEM). It was revealed, that small amount of Ni additive to the metal powder allows the production of dense and tough TiC.
Porous Ceramic Supports Prepared from Porcelain Mixture
Authors: Sharmiwati M.S. , Ahmad Zainal Arifin , Othman Mohd Roslee
Published: December 2012

The present paper reports the polymeric sponge method of porous ceramic supports from porcelain mixtures. In this work, polyurethane (PU) foam with three different pore sizes have been selected, which are 100 ppi and 120 ppi as a substrate (support) and 10 ppi as an intermediate layer (catalyst support). In addition, the tubular support shape is selected, which its provide mechanical strength to intermediate layer and membrane layer to withstand the stress induced by the pressure applied over the whole supports. Tubular configuration has been produced by polymeric sponge method. The foam with 120 ppi has a positive effect on the porosity ratio of supports compared to those prepared from 100 ppi. Moreover, the influence of the sintering temperature on the total porosity, average pore size and compressive strength of supports has been investigated.
Bamboo Sawdust as a Reduction Agent in Leaching Applications: Characterization Studies
Authors: Ismail S. , Abdullah Norazharuddin Shah , Hussin H. , Saiyid Hashim S.F.
Published: December 2012

One of the promising and environmentally friendly hydrometallurgical processes for the recovery of manganese is acid leaching in the presence of carbohydrate as a reducing agent. The aim of this study is to characterize bamboo sawdust (BSD), in particular, the carbohydrate within, for possible usage as a reduction agent in acid leaching applications. Characterization were done using Malvern analyzer (particle size distribution), SEM (morphology), XRD (crystalline index) and FTIR (molecular framework). Detailed BSD constituents were also analyzed, to determine the cellulose, hemicellulose and lignin content. Results exhibited a wide size range distribution with a span value of 1.86, and geometric mean diameter of ~100 µm. The dominant composition, meanwhile, were cellulose (38.96%) hemicellulose (26.95%) and lignin (25.86%). The morphology characteristic by SEM revealed a smooth fibrous surface with multiple aligned bundles. The assessable crystalline index of cellulose was 56.12%. The molecular framework of cellulose, hemicellulose and lignin were clearly illustrated in BSD. The obtained characteristics are valuable information in utilizing BSD as a source of carbohydrate for leaching application.
Pb(Zr0.52Ti0.48)O3 Ceramics Synthesized Using Planetary Ball Mill
Authors: Sharif Shafiza Afzan , Mohamed Julie Juliewatty , Yusoff W.A.W.
Published: December 2012

Lead zirconate titanate Pb (Zr0.52Ti0.48)O3, (PZT) ceramic was successfully prepared from the mixture of commercial PbO, TiO2 and ZrO2 powders using planetary ball mill at room temperature. The phase formation and microstructure of the milled powders were characterized using X-ray diffraction (XRD) and Scanning Electron Microscope (SEM). XRD results indicated that the perovskite phase of PZT was formed from the mixture of starting materials after milling for 40 h. The grain sizes of the powders have been estimated from the SEM images to be ~200 nm. The compacted PZT samples were then sintered at 950 °C for 1 h. The samples were characterized by XRD and SEM, meanwhile the density was measured by Archimedes principle. XRD analysis on the sintered samples revealed the formation of single phase Pb (Zr0.52Ti0.48)O3 ceramics while the SEM images estimated the grain size to be ~2 µm. The relative density of the obtained sintered PZT ceramics was measured to be approximately 99.93 % of the theoretical density. The results hence indicate that planetary ball mill is an effective preparatory technique to improve the sinterability of PZT ceramics.
Modeling Microfibril Angle and Tree Age in Acacia mangium Wood Using X-Ray Technique
Authors: Tamer Tabet A. , Abdul Aziz Fauziah , Abdulla Noraini
Published: December 2012

The term microfibril angle (MFA) in wood refers to the angle between the spiralling cellulose fibrils and the long axis of the tracheid cell wall. Diffraction patterns arising from crystal planes of various sample forms of wood trees had attracted scientific research in determining the crystallographic measurements. As such the tropical hard wood in Sabah, Acacia mangium was chosen for experimental data. Age-contributing factors were measured; the angle of reflection (θ), relative intensity, full width at half maximum (FWHM), the nearest between two neighbouring atoms in the crystalline structure (d-spacing) and the peak height, had been taken into account at different ages, pith and bark of tree. Regressions were done in comparing the microfibril angle, MFA at different ages using the least-square method and cubic-spline interpolation. The latter was able to interpolate a polynomial up to the third order. The range of the optimum angle was found to have benefited foresters in deciding the time for tree cropping and harvesting.
Mechanical Alloying of Fe-Nb-N with Different Ball to Powder Weight Ratio for the Formation of Fe-NbC Composite
Authors: Rasib Siti Zalifah Md , Hussain Zuhailawati
Published: December 2012

Milling process through mechanical alloying method was performed on a powder mixture of Fe-80.11 wt%, Nb-17.62 wt% and C-2.26 wt% to produce Fe-NbC composite by in situ reaction. Ball to powder weight ratio parameter was selected since formation of phase and microstructure characteristics of this composite were expected to depend on ball collision event during milling. The as-milled and sintered Fe-NbC was characterized by X-ray diffraction (XRD) and Scanning Electron Microscopic (SEM). We found that formation of Fe-NbC by in situ required mechanical alloying of the mixture using 10:1 of ball to powder weight ratio to achieve small crystallite size and more homogeneous of NbC phase.
Osteocyte Characterization on Polydimethylsiloxane Substrates for Microsystems Applications
Authors: York Spencer L. , Arida Ahmad R. , Shah Karan S. , Sethu Palaniappan , Saunders Marnie M.
Published: December 2012

In the body, osteocytes reside in lacunae, lenticular shaped cavities within mineralized bone. These cells are linked to each other and surface-residing osteoblasts via physical channels known as gap junctions. It has been suggested that osteocytes sense mechanical load applied to bone and relay that signal to osteoclasts and osteoblasts. Current in vitro and in vivo models of mechanotransduction face temporal and spatial barriers. Recent advances in polydimethylsiloxane (PDMS) based microfabrication techniques may be able to overcome some of these hurdles. However, before the bone research field can effectively utilize microsystems techniques, fundamental groundwork must be completed. This study characterized the behaviour of osteocytes on PDMS coated with collagen type I (CTI) and provides the framework for bone cell mechanotransduction studies using microsystems. The goal was to determine whether osteocytes were adversely affected by the substrate material by comparing their behaviour to a standard glass substrate. In addition, optimal culture conditions and time points for growing osteocytes on PDMS substrates were determined. Results of this study suggested that use of PDMS does not adversely affect osteocyte behaviour. Furthermore, the results demonstrated that osteocytes should be cultured for no less than 72 hours prior to experimentation to allow the establishment and maintenance of phenotypic characteristics. These results completed essential groundwork necessary for further studies regarding osteocytes in microsystems modelling utilizing PDMS.
A Novel Patient-Specific Regenerative Meniscal Replacement System
Authors: Chan Annabelle , Young Noel , Tran Giang T. , Miles Brad , Ruys Andrew John , Boughton Philip
Published: December 2012

Knee meniscal injuries account for the greatest number of surgical procedures performed by orthopaedic surgeons worldwide. Each year in excess of 400,000 operations are performed in Europe and over one million in the United States and yet no suitable replacement for the meniscus is available. Fibrocartilage tissue engineering holds great potential in the regeneration of meniscal tissue however current developments have been limited. Difficulties in imitating the anisotropic nature of the meniscus, patient specific geometry, attaining sterility assurance requirements remain as developmental challenges for meniscal scaffold devices. A novel approach was developed to rapidly form terminally sterilized pre-packaged scaffold templates into anatomically matched regenerative meniscal implants. Formed meniscal implants exhibited the structural and functional architecture of the native meniscus. Meniscal implants fabricated using this method displayed mechanical properties approaching to that of the native meniscus and imparted rotational stability. Fixation techniques influenced the biomechanical response of implants and 45S5 bioactive glass modification was found to enhance radio-opacity of the scaffold. Biocompatibility of the implant was confirmed using a fibroblast cell culture model.
Flabellate Bi2Mo0.5W0.5O6 Solid Solution Synthesized via PEG6000-Assisted Hydrothermal Process
Authors: Zhu Zhen Feng , Wang Yu , Yu Hong Guang , Li Jun Qi
Published: December 2012

The hierarchical structure of flabellate Bi2Mo0.5W0.5O6 solid solution has been successfully synthesized by a facile hydrothermal method in the presence of a surfactant of PEG6000. The as-synthesized products are composed of nanosheets with similar orthorhombic Aurivillius layered structures. The flabellate Bi2Mo0.5W0.5O6 solid solution has an average length of 4~5μmand width of 3~4μm and is composed of oblong nanosheets which has a length of several hundred nanometers, a width of ~600nm and a thickness of ~50nm. FT-IR spectra suggest that PEG6000 plays a vital role in the formation process of the flabellate Bi2Mo0.5W0.5O6 hierarchical structures. UV-vis spectra indicate that the flabellate Bi2Mo0.5W0.5O6 solid solution possessed photo absorption properties in the visible light region. The flabellate Bi2Mo0.5W0.5O6 solid solution exhibits highly efficient visible-light-driven activity for degradation of Rhodamine-B (RhB) under the 500W Xe lamp light irradiation.
An investigation to determine the cause of haemorrhagic enteritis in commercial pig grower units in the northern parts of South Africa
Authors: Labuscagne Annemarie , Spencer B. Tom , Picard Jackie A. , Williams Mark C.
Published: December 2012

Necropsies were performed on 36 grower pigs that died peracutely on farms in the northern parts of South Africa. All these pigs were suffering from haemorrhagic enteritis and suspected toxaemia. Samples of the duodenum, jejunum and ileum were taken for histopathological examination and a section of ileum was collected for microbiological examination from each animal. Histological lesions characteristic of enterotoxigenic Clostridium infection were found. Large, Gram-positive bacilli were sometimes abundant in sections and mucosal smears of the intestine. However, only 40% of the cultures were positive for Clostridium perfringens.
Rumenolith formation in a Bapedi ram
Authors: Leask Rhoda , Bath Gareth F.
Published: December 2012

During a routine flock visit, a farmer observed that one of the eight tooth Bapedi rams had been losing body condition despite being separated from the flock and fed supplementary feed. The ram’s body condition score was assessed as 2 out of 5 (one point less than the average of the rest of the rams) and the teeth appeared normal with no excessive wear. The rumen was assessed by auscultation, palpation and ballottement where a foreign body (approximately 20 cm × 5 cm – 10 cm) was clearly palpated and ballotted. A rumenotomy was performed and a large mass of tightly compacted foreign matter and plant material was removed. The mass consisted of synthetic fibre, plant material and calcium phosphate (50.5%). It appeared to have formed as the result of the ingestion of a synthetic fibre which formed the nidus of a concretion. This was probably the result of deficient nutrition, with the rams eating the synthetic fibre in an attempt to increase feed intake. The ram recovered uneventfully after the rumenotomy was performed and supplementary feeding.
Simulation and analysis of microwave heating while joining bulk copper
Authors: Srinath M.S. , Murthy P. Suryanarayana , Sharma Apurbba Kumar , Kumar Pradeep , Kartikeyan M.V.
Published: December 2012

Processing of bulk metallic materials using microwave energy is challenging. However, in this work microwave heating has been successfully employed for joining of bulk copper. The present work illustrates the joining process using COMSOL simulation tool. The work complements the experimental results of the microwave heating of bulk copper in a multimode microwave applicator. In electromagnetic processing, thermal dissipation in the bulk metal may be attributed to resistive heating, dielectric and magnetic losses. This dissipative mechanism is coupled to the fields by the conductivity, permittivity and permeability of the metal. The model has been created for heating of the bulk metal in a microwave oven by considering the radio frequency of the microwaves. The distributed power and heat source were computed in a stationary, frequency domain electromagnetic analysis and coupled to a transient heat transfer simulation showing the heat distribution in the bulk copper joint. The maximum power observed at the joint interface is 6.0618×108 W/m3 with an average power is 3×108 W/m3. However, the temperature will be around 1144˚C was attained in 300 s at the joint interface while the parent material is about 940 ˚C. The simulation results are in good agreement with the experimental one.Keywords: Microwave heating, FEM Model, Simulation, Copper Joint, Resistive Heating.
An investigation on weld quality characteristics of pulsed current micro plasma arc welded austenitic stainless steels
Authors: Prasada Kondapalli Siva , Raob Chalamasetti Srinivasa , Raoc Damera Nageswara
Published: December 2012

Micro Plasma Arc Welding (MPAW) is one of the important arc welding process commonly used in sheet metal industry for manufacturing metal bellows, metal diaphragms etc. The present work discusses about the weld quality characteristics of various austenitic stainless steels namely AISI 304L, AISI 316L, AISI 316Ti, AISI 321 which are commonly used for manufacturing of metal bellows. Square butt joint is used in the welding and no filler wire is used. Welding is carried out at fixed values of input parameters and same thickness of 0.25mm for all the steels. Peak current, background current, pulse rate and pulse width are considered as the main welding process parameters of MPAW process, where as weld bead geometry, microstructure, grain size, hardness and tensile properties are considered as weld quality  characteristics. Results reveal that out of all the materials considered in the study AISI 304L attains better weld quality characteristics for same welding conditions.Keywords: Pulsed current micro plasma arc welding, microstructure, grain size, hardness, tensile properties.
Weld metal characterization of 316L(N) austenitic stainless steel by electron beam welding process
Authors: Joseph Benjamin , Katherasan D. , Sathiya P. , Murthy C. V. Srinivasa
Published: December 2012

Electron beam welding (EBW) is a fusion joining process that produces a weld by impinging a beam of high energy electron to the weld joint. EBW has been used widely due to its advantages like narrow weld zone and heat affected zone, low distortion and contamination etc. The present work is focused on EBW of 316L(N) austenitic stainless steel varying the welding parameters such as beam power and welding speed. This study is carried out by analyzing the mechanical and metallurgical properties of the welded material. The mechanical properties have been evaluated using tensile, impact, hardness and bend test in accordance with the ASTM standards. The metallurgical characteristics are further investigated through optical microscopy. The mechanical properties of the weld material are better than the parent material. The variations of the mechanical properties were related with the variations in the cooling rate of the weld metal. The change in the cooling rate has influenced the grain size which has in turn influenced the mechanical properties. The metallurgical factors such as the presence of the ferrite and its percentage were also considered to substantiate the variation in the characteristics of the weld metal.Keywords: electron beam welding, 316L (N), beam current, gun voltage.