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Full-Text Articles in Engineering

Effect Of Preparation Conditions On Electroluminescence Of Porous Silicon, Ya-Jun Yang, Qing-Shan Li, Xian-Yun Liu, Ning Zhang, Bo Zhao, Xue-Gang Zheng, Ming-Ji Shi, Da Chen, Jing-Jing Wang May 2006

Effect Of Preparation Conditions On Electroluminescence Of Porous Silicon, Ya-Jun Yang, Qing-Shan Li, Xian-Yun Liu, Ning Zhang, Bo Zhao, Xue-Gang Zheng, Ming-Ji Shi, Da Chen, Jing-Jing Wang

Journal of Electrochemistry

Electrically induced visible light emitting porous silicon devices with the structure of ITO/PS/p-Si/Al were fabricated by evaporation-anodic oxidation method.The light emission last for a few hours under 7.5V forward bias conditions.It was shown that the electroluminescence(EL) peaks shifted to the blue with the increasing of current density,erosion time and solution concentration.In order to achieve samples with low driven voltage,long light emission time and high EL efficiency,porous silicon should be prepared under low current density and short erosion time.


Electrochemical Preparation And Application Of Nanomaterials, Peng Liu, Ye-Xiang Tong, Qi-Qin Yang May 2006

Electrochemical Preparation And Application Of Nanomaterials, Peng Liu, Ye-Xiang Tong, Qi-Qin Yang

Journal of Electrochemistry

Nano materials and nano technology receive great attention all over the world.While electrochemistry has already achieved a great application in industry and it has proved that electrochemistry will play an important role in the field,such as energy source,new materials,life sciences,information sciences,environment and nano sciences.In this paper,the recent developments of electrochemical techniques for the preparing nano materials,application of nano materials in the areas of electrodeposition,batteries,electrocatalysis,sensors are introduced in brief.


Compare Of The Behavior Of Different Sloth Filler Bipolar Packed Bed Cell In The Treatment Of Sodium P-Nitro-Phenolate, Shi-Yuan Guo, Ai-Li Zhang, Ji-Ti Zhou May 2006

Compare Of The Behavior Of Different Sloth Filler Bipolar Packed Bed Cell In The Treatment Of Sodium P-Nitro-Phenolate, Shi-Yuan Guo, Ai-Li Zhang, Ji-Ti Zhou

Journal of Electrochemistry

Making use of sulphonated coal,fruit hull,plastic of PVC,old plastic in recovery,four kinds of sloth fillers which densities are equal to active carbon to substitute quartz sand which are applied in project extensively.And link with appropriate backwashing to resolve the problem of electrodes pollution and &lamination of the fillers in the bipolar packed bed cell.Then via the treatment of the waste water that contains sodium p-ni-tro-phenolate to investigate the possibility of application.The results are as follow.There are better resuk for the reactors packed with old plastics in recovery and sulphonated coal than the one filled with quartz sand,and the results of …


Electrochemical Impedance Spectrum Of Ferrocene At A Rotating Disk Glassy Carbon Electrode And Its Interaction With Dna, Can-Hui Chen, Hong Li, Jian-Zhang Zhou, Zhong-Hua Lin, Wei Zhu, Quan-Xin Zhang May 2006

Electrochemical Impedance Spectrum Of Ferrocene At A Rotating Disk Glassy Carbon Electrode And Its Interaction With Dna, Can-Hui Chen, Hong Li, Jian-Zhang Zhou, Zhong-Hua Lin, Wei Zhu, Quan-Xin Zhang

Journal of Electrochemistry

The electrochemical impedance spectrum(EIS) of ferrocene(Fc) at a rotating glassy carbon(GC) electrode and its interaction with calf thymus DNA in Tris-NaCl buffer solution(pH=7.2) have been investigated by using electrochemical techniques such as rotating disk electrode(RDE),EIS and its data fitting.A plateau of the limiting current for the voltammetric curve and two capacitance arches obtained at the rotating GC electrode are exhibited.The interaction of Fc with DNA is represented by the decrease of limiting diffusion current and the increase of electrochemical reaction resistances with the increase of DNA concentration,respectively.On the other hand,based on the theoretical analysis and data fitting of RDE and …


Structure And Properties Of Electrodeposited Sn-Co Alloy Electrodes As Anode Material For Lithium-Ion Secondary Batteries, Hong-Hong Jiang, Ling Huang, Shun-Wei Zhou, Fu-Sheng Ke, Fang-Zu Yang, Xiao-Yong Fan, Shi-Gang Sun May 2006

Structure And Properties Of Electrodeposited Sn-Co Alloy Electrodes As Anode Material For Lithium-Ion Secondary Batteries, Hong-Hong Jiang, Ling Huang, Shun-Wei Zhou, Fu-Sheng Ke, Fang-Zu Yang, Xiao-Yong Fan, Shi-Gang Sun

Journal of Electrochemistry

The Sn-Co alloy deposits were prepared by electroplating.The structure and electrochemical performance of the electroplated Sn-Co alloys have been investigated in detail. Experimental results show that the porous Sn-Co alloy film exhibits hexagonal solid solution,with Sn as the solvent, Co as the solute. The texture of the Sn-Co alloy coating exhibits(110) preferred orientation. Electrochemical tests show that the porous Sn-Co alloy coating electrodes can deliver a discharge capacity of 643mAh/g in the first cycle. At the 20h cycle the charge was 461mAh/g. At initial charge curve the irreversible capacity is probably associated to a combination of processes, which may …


High Density Lifepo4/C Synthesized By Controlled Crystallization And Microwave Carbon Thermal Reduction, Chang-Ping Tang, Jie-Rong Ying, Min Lei, Wei Li, Chang-Yin Jiang, Chun-Rong Wan May 2006

High Density Lifepo4/C Synthesized By Controlled Crystallization And Microwave Carbon Thermal Reduction, Chang-Ping Tang, Jie-Rong Ying, Min Lei, Wei Li, Chang-Yin Jiang, Chun-Rong Wan

Journal of Electrochemistry

The spherical FePO4·xH2O was prepared in the solution by controlled crystallization.The precursor FePO4 was obtained in high temperatureceramic approach,then the high density LiFePO4 /C was synthesized by microwave carbon thermal reduction.The structure and morphology of the materials were characterized by means of XRD and SEM techniques,and the electrochemical properties were studies by charge-discharge experiments.


Effect Of Cracks On Corrosion Of Rebar In Concrete Studied By Wire Beam Electrode, Guo-Xi Li, Xian-Lu Hou, Ri-Long Zhu, Jin-Feng Hu, Yan-Na Du May 2006

Effect Of Cracks On Corrosion Of Rebar In Concrete Studied By Wire Beam Electrode, Guo-Xi Li, Xian-Lu Hou, Ri-Long Zhu, Jin-Feng Hu, Yan-Na Du

Journal of Electrochemistry

The effects of crack and ethanolamine on corrosion of rebar in concrete were studied by measuring the distribution of corrosion potential and polarization resistance of iron wires in 10% NaCl solution.The results showed that the diffusion of water,oxygen and chloric ion toward concrete was accelerated by the crack which intensified the nonuniform corrosion of iron wire with the regions near to crack as anode and the uncracked regions as cathode.Ethanolamine could diffuse into the body of concrete and absorb on the surface of iron wire,which reduced iron corrosion evidently and successfully inhibited the nonuniform corrosion caused by crack without changing …


Tyrosinase Immobilizarion On Boron-Doped Diamond Electrodes And The Determination Of Phenolic Compounds, Yan-Li Zhou, Jin-Fang Zhi May 2006

Tyrosinase Immobilizarion On Boron-Doped Diamond Electrodes And The Determination Of Phenolic Compounds, Yan-Li Zhou, Jin-Fang Zhi

Journal of Electrochemistry

As-grown BDD surfaces were first functionalized by photochemically linking vinyl groups of allylamine,producing covalently linked amine-terminated active BDD surfaces.Then the tyrosinase was immobilized onto the BDD surface through peptide linking.Cyclic voltammograms of phenol,pcresol and hydroquinone were measured using the tyrosinase-modified BDD electrode and amperometric characteristics such as sensitivity,linear response range and stability were studied.


Electrochemical Studies On Electrocatalytic Activity Of AuCore PtShell Nanoparticles To Methanol Oxidation, Fang Bao, Jian-Lin Yao, Ren-Ao Gu May 2006

Electrochemical Studies On Electrocatalytic Activity Of AuCore PtShell Nanoparticles To Methanol Oxidation, Fang Bao, Jian-Lin Yao, Ren-Ao Gu

Journal of Electrochemistry

AucorePtshell nanoparticles with different thicknesses were prepared by using chemical reduction method,and characterized by ultraviolet-visible spectroscopy(UV-Vis),transmission electron microscopy(TEM) and cyclic voltammetry(CV).The electrocatalytic activity of AucorePtshell nanoparticles with the mean diameter of 70~80 nm to methanol oxidation was investigated by cyclic voltammetry in the acid solution.The results revealed that the prepared core-shell nanoparticles were covered by Pt shell and exhibited the similar optical property and electrocatalytic activity with the normal Pt surface.Moreover,the electrocatalytic activity increased with the electrochemical sweep in the certain potential range.It might be contributed by the special loose structure of Pt shell …


Electrochemical Preparation Of Gd-Ni Alloy Film In Acetamide-Urea-Nabr Melt, Bi-Qing Chen, Jian-Chao Wang, Chen-Yu Guo, Jin-Gui Wang, Qing Liu May 2006

Electrochemical Preparation Of Gd-Ni Alloy Film In Acetamide-Urea-Nabr Melt, Bi-Qing Chen, Jian-Chao Wang, Chen-Yu Guo, Jin-Gui Wang, Qing Liu

Journal of Electrochemistry

Cyclic voltammetry was used to study the electroreduction of Ni2+ to Ni on Pt and Cu electrode in acetamide-urea-NaBr melt at 353K.It is irreversible in one step.At Pt and Cu eletrode the diffusion coefficient and electron transfer coefficient of Ni2+ in 0.063mol/dm3) NiCl2-acetamide-urea-NaBr melt were determined.The transfer coefficient α=0.28 and diffusion coefficient D_(0)=4.63×10-5 cm2·s-1 of the Pt eletrode and transfer coefficient α=0.22 and diffusion coefficient D_(0)=6.05×10-7 cm2·s-1 of the Cu eletrode were measured.It was put emphasis on that Gd3+ is not reduced to Gd alone …


Study On Composite Organic Inhibitor Of Zinc Electrode In Alkaline Solutions, Xue-Tao Bu, Guang-Chuan Liang, Cui Li May 2006

Study On Composite Organic Inhibitor Of Zinc Electrode In Alkaline Solutions, Xue-Tao Bu, Guang-Chuan Liang, Cui Li

Journal of Electrochemistry

The synergetic influence of sodium dodecyl benzene sulfonate(SDBS) with Tween-20(Tween) on zinc electrode was studied by polarization experiment,surface tension test,discharge test and SEM.It is found that the composite inhibitor ST has a much higher efficiency.The addition of Tween reduced the critical micell concentration of SDBS on zinc electrode remarkably and the distribution of adsorption became more homogeneous.ST inhibits corrosion of zinc electrode and improves discharge capacity of the whole battery.Through electrochemical morphological observation of anodic passivation behaviors of zinc electrode,the absorption of ST on electrode surface makes discharged production much smaller and keeps crude porous structure intact.Passivation of zinc electrode …


Bs News May 2006

Bs News

Building Services Engineering

No abstract provided.


Mobile Messaging In The Pacific Rim, Thomas Asmuth May 2006

Mobile Messaging In The Pacific Rim, Thomas Asmuth

SWITCH

This article explores the growth of mobile messaging across the Pacific Rim, focusing on how cultural, economic, and infrastructural factors shape its use.


Ole Miss Engineer 2006 Apr 2006

Ole Miss Engineer 2006

Ole Miss Engineer

No abstract provided.


Effect Of Firing Temperature And Holding Time On Characterization Of Al/Sic Metal Matrix Composites Produced By Pressureless Infiltration., Anne Zulfia, Myrna Ariati Apr 2006

Effect Of Firing Temperature And Holding Time On Characterization Of Al/Sic Metal Matrix Composites Produced By Pressureless Infiltration., Anne Zulfia, Myrna Ariati

Makara Journal of Technology

Effect of Firing Temperature and Holding Time on Characterization of Al/SiC Metal Matrix Composites Produced by Pressureless Infiltration. The production of Al-SiC metal matrix composite can be carried out by pressureless metal infiltration processs (PRIMEX). The experiment was conducted using aluminium AC2B ingot as a matrix and 50%Vf SiC powder as a reinforcement which is mixed with 10% Mg powder for wetting agent. The variables of this experiment are holding time and firing temperature to investigate the effect of these conditions on mechanical properties of Al-SiC metal matrix composites. Holding time was conducted for 2,5,8,10,12 hours and firing temperatures was …


Modification Of Bonding Strength Test Of Wc Hvof Thermal Spray Coating On Rocket Nozzle, Bondan T. Sofyan, Haposan J. Pardede, Marizki Stefano, Edi Sofyan Apr 2006

Modification Of Bonding Strength Test Of Wc Hvof Thermal Spray Coating On Rocket Nozzle, Bondan T. Sofyan, Haposan J. Pardede, Marizki Stefano, Edi Sofyan

Makara Journal of Technology

Modification of Bonding Strength Test of WC HVOF Thermal Spray Coating on Rocket Nozzle. One way to reduce structural weight of RX-100 rocket is by modifying the nozzle material and processing. Nozzle is the main target in weight reduction due to the fact that it contributes 30 % to the total weight of the structur. An alternative for this is by substitution of massive graphite, which is currently used as thermal protector in the nozzle, with thin layer of HVOF (High Velocity Oxy-Fuel) thermal spray layer. This paper presents the characterization of nozzle base material as well as the modification …


Development Of Fiber-Optic Humidity Sensor Probe With Gelatin Cladding, Akhiruddin Maddu, Kun Modjahidin, Sar Sardy, Hamdani Zain Apr 2006

Development Of Fiber-Optic Humidity Sensor Probe With Gelatin Cladding, Akhiruddin Maddu, Kun Modjahidin, Sar Sardy, Hamdani Zain

Makara Journal of Technology

Development of Fiber-Optic Humidity Sensor Probe with Gelatin Cladding. Humidity sensor based on optical fiber with gelatin cladding has been developed. In this humidity sensor probe, the origin cladding of optical fiber is replaced by gelatin coating as humidity sensitive cladding. Testing of the optical fiber sensor probe was conducted by measuring of light intensity transmitted on the optical fiber probe for each variation of different humidity treatments. Response of the optical fiber sensor probe measured from 42%RH to 99%RH, the results show an optical transmission curve varied with relative humidity (RH). Optical transmission in the optical fiber probe increase …


Bs News Apr 2006

Bs News

Building Services Engineering

No abstract provided.


On The Performance Of Imt-2000 Communication Link Based On Stratospheric Platforms, Iskandar Iskandar, Shigeru Shimamoto Apr 2006

On The Performance Of Imt-2000 Communication Link Based On Stratospheric Platforms, Iskandar Iskandar, Shigeru Shimamoto

Makara Journal of Technology

A new means for providing wireless communication has been currently proposed. It is based on aerial vehicle known as High Altitude Platform or Stratospheric Platforms (SPF). The SPF will be operated at an altitude of 17-22 km above the ground. Therefore, the channel condition may be different compared with those of the conventional terrestrial or satellite wireless channel. In this paper, the channel propagation characteristic of such a system is firstly investigated by means of ray tracing algorithm. We emphasize our investigation in a typical urban environment, in which the mobile users mostly exist. We developed building block model for …


Analysis Of Technical Energy Losses By Using Simulation, Betrianis Betrianis, Randite Herawan Apr 2006

Analysis Of Technical Energy Losses By Using Simulation, Betrianis Betrianis, Randite Herawan

Makara Journal of Technology

Model is a representation of a system. Through model, it can be easier to forecast and control the changing of each element system. Electricity distribution is also a system. Losses are general problem that exist in a distribution network system. But with the right methods, specifically technical energy losses can be reduced in order to increase the efficiency. By making model of the distribution network, the value of technical energy losses in the whole network as well as in every line can be observed. Simulation can also be used to see all losses reduction alternatives. By comparing results from each …


Modeling Of Coupled-Tank System Using Fuzzy Takagi-Sugeno Model, Aries Subiantoro Apr 2006

Modeling Of Coupled-Tank System Using Fuzzy Takagi-Sugeno Model, Aries Subiantoro

Makara Journal of Technology

Modeling of Coupled-Tank System Using Fuzzy Takagi-Sugeno Model. This paper describes modeling of coupledtank system based on data measurement using fuzzy Takagi-Sugeno model. The fuzzy clustering method of Gustafson- Kessel algorithm is used to classify input-output data into several clusters based on distance similarity of a member of input-output data from center of cluster. The formed clusters are projected orthonormally into each linguistic variables of premise part to determine membership function of fuzzy Takagi-Sugeno model. By estimating data in each cluster, the consequent parameters of fuzzy Takagi-Sugeno model are calculated using weighted least-squares method. The resulted fuzzy Takagi-Sugeno model is …


Design Of Induction Motor Drive Without Velocity Sensor Using Current Vector Controller With Full And Reduced Observer Moving To Dq Axis, Ridwan Gunawan, Feri Yusivar, Wahidin Wahab, Zuhal A. Kadir Apr 2006

Design Of Induction Motor Drive Without Velocity Sensor Using Current Vector Controller With Full And Reduced Observer Moving To Dq Axis, Ridwan Gunawan, Feri Yusivar, Wahidin Wahab, Zuhal A. Kadir

Makara Journal of Technology

Design of Induction Motor Drive Without Velocity Sensor Using Current Vector Controller with Full and Reduced Observer Moving to DQ Axis. The observer is used in estimation velocity sensor usually in α-β axis, therefore this situation will need an extra transformation when we want to add compensator because the flux model is in direct and quadrature-axis dq. Every used the transformation to make possible emerge an error. So in this simulation is used a method to estimate the velocity of induction motor drive with observer that is moved to dq-axis. The model of actual motor used is in alfa-beta axis, …


Hybrid Identification System With Arx And Fast Fourier Transform In Application Of A Quarter Of Vehicle Half Active Suspension, Noveri Lysbetti M, Antonius R. Apr 2006

Hybrid Identification System With Arx And Fast Fourier Transform In Application Of A Quarter Of Vehicle Half Active Suspension, Noveri Lysbetti M, Antonius R.

Makara Journal of Technology

Hybrid Identification System with ARX and Fast Fourier Transform in Application of a Quarter of Vehicle Half Active Suspension. In a control system problem, identification system mechanism is a absolute thing, especially in adaptation controlling to disturbance changing. For that case, is needed an identification method which can identify the changing of disturbance in that system. The aim of this research is to give an alternative in system/plant identification which is a combination (hybrid) of ARX and Fast Fourier Transform. So, it is needed an algorithm design for identification process. In this case, the designed algorithm will be implemented in …


Performance Analysis Of Mc-Cdma Communication Systems Over Nakagami-M Environments, Joy Iong-Zong Chen Mar 2006

Performance Analysis Of Mc-Cdma Communication Systems Over Nakagami-M Environments, Joy Iong-Zong Chen

Journal of Marine Science and Technology–Taiwan

The performance for a MC-CDMA (multi-carrier coded-division multiple-access) system working in uncorrelated and correlated fading channels with Nakagami distribution is investigated in this paper. We adopt the BPSK modulation scheme with an alternative expression for Q-function to evaluate the BER (bit error rate) performance of the MC-CDMA system. The sum of Gamma variates is adopted for deriving a closed-form solution for arbitrarily correlated channel in order to avoid the difficulty of explicitly obtaining the pdf (probability density function) for the SNR (signal-to-noise ratio) at the MRC (maximum ratio combining) output. The results with simple expression obviously show that the BER …


Bearing Capacity Of Foundations On Sand Using The Method Of Slip Line, Meen-Wah Gui, Muhunthan Mar 2006

Bearing Capacity Of Foundations On Sand Using The Method Of Slip Line, Meen-Wah Gui, Muhunthan

Journal of Marine Science and Technology–Taiwan

The accurate prediction of the bearing capacity of shallow foundations on granular soils has been complicated by their stress dependent strength behavior and the surface roughness of the foundationsoil interface. These are accounted for using empirical relations in the current state of practice. In this study, the stress dependent behavior of soils is accounted for using a strength dilatancy relationship. The method of slip line has been extended to incorporate this relationship and the effects of surface roughness to derive the depth dependent bearing capacity factor Nq. The results are presented in terms of angle of friction, depth/diameter ratio, and …


Experimental Study On The Performance Of Ship Fire Protection Materials, Jen-Chieh Lee, Shi-Jie Liu Mar 2006

Experimental Study On The Performance Of Ship Fire Protection Materials, Jen-Chieh Lee, Shi-Jie Liu

Journal of Marine Science and Technology–Taiwan

The performance of heat insulation, sound absorption and insulation of ship fire protection materials is experimentally investigated in this paper. The fire protection materials of rock wool 60 k (60 kg/m3 ) and ceramic fiber 80k (80 kg/m3 ) are tested to show the requisite minimum thickness for the regulation of IMO heat insulation A class. The results show that the heat insulation performance of ceramic fiber (25 mm) and rock wool (50 mm) meets the requirement of A-30 class bulkhead. However, the composition of ceramic fiber (25 mm) and rock wool (25 mm) with the ceramic fiber exposed to …


State Variance Constrained Fuzzy Control Via Observer-Based Fuzzy Controllers, Wen-Jer Chang, Balasingam Yeh, Yu-Teh Meng Mar 2006

State Variance Constrained Fuzzy Control Via Observer-Based Fuzzy Controllers, Wen-Jer Chang, Balasingam Yeh, Yu-Teh Meng

Journal of Marine Science and Technology–Taiwan

In this paper, a state variance constrained design method is developed to deal with the observer-based fuzzy control problem for continuous Takagi-Sugeno (T-S) fuzzy stochastic models. The stability problem considered in this paper is a standard feasibility problem with several Linear Matrix Inequalities (LMIs), which can be solved numerically using the interior-point method. The purpose of this paper aims at finding observer-based fuzzy controllers such that the closed-loop system is asymptotically stable and the state variance performance constraints are satisfied. Finally, a numerical example is included to demonstrate the effectiveness of the proposed controller design method.


Imperative Of National Savings: A Case For Adoption Of Appropriate Benchmark Price For Crude Oil., Moses F. Otu Mar 2006

Imperative Of National Savings: A Case For Adoption Of Appropriate Benchmark Price For Crude Oil., Moses F. Otu

Bullion

Budgeting involves the design of plans that aligns expected financial resources and expenditure to accomplish specific national goals and objectives. It is in this regard that this paper provides a simple framework for deriving an acceptable bench-mark price for crude oil for budgeting purposes. This is aimed at enabling the elimination of subjectivity in budgeting process and promote understanding between all the stakeholders in order to fast track the process of passage of the appropriation bill. Following a brief introduction, the paper examines the need for national saving fund and constitutional provisions for national savings. Section three focuses on the …


Bs News Mar 2006

Bs News

Building Services Engineering

No abstract provided.


Electroless Nickel Plating On Carbon Nanotube With Non-Palladium Activation Procedure, Guang-Hui Hu, Hui-Huang Wu, Fang-Zu Yang Feb 2006

Electroless Nickel Plating On Carbon Nanotube With Non-Palladium Activation Procedure, Guang-Hui Hu, Hui-Huang Wu, Fang-Zu Yang

Journal of Electrochemistry

A new procedure of surface activation without using palladium salt was proposed for electroless nickel plating on carbon nanotubes.In the procedure,carbon nanotubes were oxidized by nitric acid and then neutralized with NaOH to create carboxyl surface groups which were used to adsorb Ni2+ ions,thereafter the adsorbed Ni2+ ions were chemically reduced into Ni nano-particles as a catalytic center for electroless nickel deposition,all these were further confirmed by infrared absorption spectra and electron microscopic observations.The results indicate that the procedure is feasible to electroless nickel plating on carbon nanotubes.The different morphology of deposits obtained from electroless plating was also …