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Articles 23641 - 23670 of 27383

Full-Text Articles in Engineering

Behavior Of Chemically Dispersed Oil In Marine Sediment, Jian Hua Jun 2009

Behavior Of Chemically Dispersed Oil In Marine Sediment, Jian Hua

Journal of Marine Science and Technology–Taiwan

This laboratory study was to describe properties of four chemically dispersed oils within natural beach sands. The influence of temperature on the adsorption characteristics of dispersed oil to marine sediment was almost negligible, within 10 to 30°C. With certain amount of oil and varied dispersant/oil ratio, oil in top sediments following flushing was not affected by the increase in dispersant application. The application dosage of dispersant had no more influence on releasing oil to deeper sediment or water than the amount of oil applied. When the outflow rate of flushing water doubled, the amounts of oil retained in surface sediment …

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Kalman Filter Effective To Hydrologic Routing?, Yang-Liang Jeng, Rong-Che Chen, Chao-He Chang Jun 2009

Kalman Filter Effective To Hydrologic Routing?, Yang-Liang Jeng, Rong-Che Chen, Chao-He Chang

Journal of Marine Science and Technology–Taiwan

Intake-generated tumbling motion has been recently proposed to enhance the turbulence level during compression stroke to promote the combustion rate and reduce operation variations. This study is to investigate the quality of the tumbling motion, especially for the engine with a bowl-in-piston. To overcome the difficulties on the flow visualization caused by the high-speed motion of a real engine, a transparent water-analogy-simulation system is designed based on similarity analysis and fabricated to model the operation of an actual engine. Benchmark tests including the qualitative flow visualization and quantitative full-field measurements using a high-speed PIA system have been conducted to study …

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Wave Forces On A Large Structure In The Presence Of A Current, Sung-Shan Hsiao, Ming-Chung Lin Jun 2009

Wave Forces On A Large Structure In The Presence Of A Current, Sung-Shan Hsiao, Ming-Chung Lin

Journal of Marine Science and Technology–Taiwan

The wave forces acting on a large structure in the presence of a current have been investigated numerically. It is noted that the velocity potential in a wave-current coexisting field can be separated into an unsteady wave potential and a steady current potential. The unsteady wave potential with effects of both a uniform current and a large structure was calculated by using boundary element method. The steady current potential can be expressed as the sum of a uniform current and a steady disturbance due to the existence of the structure. This means that current velocity will be changed in the …

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Real Time Implementation Of Frost Beamformer For Underwater Communications, Hsien-Sen Hung, Shun-Hsyung Chang, Suan-Lin Chen, Chi-Wen Chang Jun 2009

Real Time Implementation Of Frost Beamformer For Underwater Communications, Hsien-Sen Hung, Shun-Hsyung Chang, Suan-Lin Chen, Chi-Wen Chang

Journal of Marine Science and Technology–Taiwan

In this paper, we investigate the performance of Frost’s linearly constrained minimum variance (LCMV) adaptive beamformer via computer simulations for QPSK signals transmitted over Rayleigh and Rician fading channels. Simulation results show that the Frost beamformer can still improve the signal-to-interference-plus-noise ratio, even over fading channels. For real-time underwater communications, a prototype system is implemented, which uses TMS320C40 digital signal processor chip for realization of the Frost beamformer. Through experiments in an acoustic trough the validity of the real-time Frost beamformer prototype system is verified, and the feasibility of its use in underwater communications is assessed.

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Decision Analysis For Construction Contract Risk-Sharing, Teh-Chang Lee, Ta-Hsing Lee, Ching-Hwang Wang Jun 2009

Decision Analysis For Construction Contract Risk-Sharing, Teh-Chang Lee, Ta-Hsing Lee, Ching-Hwang Wang

Journal of Marine Science and Technology–Taiwan

As the risk-sharing provisions in domestic public construction contracts are not completely fair and reasonable, contract disputes often arise as a result which in turn cause delays, quality impacts, and other problems that urgently need improvement. Introduced in this article is the development of a decision system for risk-sharing in public construction contracts. Said system was developed through literature review, questionnaire and interviews of experts, fuzzy synthetic evaluation in conjunction of analytic hierarchy process, definition of risks in public construction contracts, and establishment of decision models for risk-sharing. Subsequently, the “escalation” risk was employed as an example to select suitable …

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Residual Vibrations Of Electrostatic Micro-Actuators With Novel Shaped Cantilevers, Ming-Hung Hsu Jun 2009

Residual Vibrations Of Electrostatic Micro-Actuators With Novel Shaped Cantilevers, Ming-Hung Hsu

Journal of Marine Science and Technology–Taiwan

This paper subjects electrostatic curved electrode actuators with novel shaped cantilevers to nonlinear dynamic analysis using the differential quadrature method. Numerical results are compared with experimental results to assess the efficiency and systematic procedure of this novel approach for nonlinear differential equations. The pull-in voltages computed for different structures correlate well with published data. Several characteristics of different combinations of shaped cantilevers and curved electrodes are also examined in this paper. Dynamic responses of actuators with novel shapes with several pull-in voltages are determined. The transitional responses for the derived systems are calculated using the Wilson-θ method.

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Evaporation Effect In Nonlinear Penetration Of High Energy Beam Drilling, Je-Ee Ho, Chen-Lung Yen Jun 2009

Evaporation Effect In Nonlinear Penetration Of High Energy Beam Drilling, Je-Ee Ho, Chen-Lung Yen

Journal of Marine Science and Technology–Taiwan

Due to the inappropriate assumption with the neglect of evaporation effect in previous research, a linear penetration behavior with a significant deviation from the experimental result was usually proposed in the lower energy density region. To remedy the defect, the evaporation mass determined from the difference between the melting rate and flow expulsion by pressure difference is reconsider in this study. With a 2-D quasic-steady model based on the enthalpy theory, the uniform penetration velocity estimated from the Stefan boundary condition provides a special advantage in calculating efficiency. Meantime, the divergent iteration has been effectively avoided by setting up a …

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Inductively/Capacitively Coupled Conductor-Backed Coplanar Waveguide Bandpass Filters Using Slow-Wave Stepped-Impedance Resonators, Jiunn-Jye Chang, Chih-Hong Sie Jun 2009

Inductively/Capacitively Coupled Conductor-Backed Coplanar Waveguide Bandpass Filters Using Slow-Wave Stepped-Impedance Resonators, Jiunn-Jye Chang, Chih-Hong Sie

Journal of Marine Science and Technology–Taiwan

In this paper, using the conductor-backed coplanar waveguides (CBCPWs) and the slow-wave stepped-impedance resonators, a second-order and a fourth-order inductively/capacitively coupled bandpass filters are designed, implemented, and measured. For second-order bandpass filter, two H-shaped defected ground structure (DGS) patterns are etched on the backside metallic ground planes of the input and output feedlines, it is found that two attenuation poles exist on both sides of the passband. When compared to the fourth-order bandpass filter without H-shaped DGS, the second-order bandpass filter with H-shaped DGS has compact size and comparable rolloff at the edges of the passband. In addition, the measured …

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Drop Impact Dynamic Response Study Of Jedec Jesd22-B111 Test Board, Jianbiao Pan, Michael Krist, Andrew Farris, Nicolas Vickers Jun 2009

Drop Impact Dynamic Response Study Of Jedec Jesd22-B111 Test Board, Jianbiao Pan, Michael Krist, Andrew Farris, Nicolas Vickers

Honors Undergraduate Research Journal

No abstract provided.

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Effect Of Liquid Dispersion On Corrosion Behavior Of Metals In Gas/Liquid/Solid Multiphase Corrosion Systems, Jing Jiang, Jia Wang May 2009

Effect Of Liquid Dispersion On Corrosion Behavior Of Metals In Gas/Liquid/Solid Multiphase Corrosion Systems, Jing Jiang, Jia Wang

Journal of Electrochemistry

Liquid dispersion,described by the parameters of gas/liquid/solid three-phase boundary(TPB) zone of dispersed liquid on a metal surface,is an important property of liquid state influencing corrosion behavior of metals in gas/liquid/solid multiphase corrosion systems.In our paper,the characterisation of cathodic oxygen reduction process in TPB zone was discussed,and a model describing the cathodic process of TPB zone was developed.On this basis,the relationship between the cathodic limiting current and the TPB parameters was studied,and the simulation results were in good agreement with the experimental data.The role of liquid dispersion in atmospheric and sandy soil corrosion systems was also simulated.

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Electrodeposition Of Al On Magnesium Alloy In Ionic Liquid, Wen-Ta Tsai, Shu-You Chen, Mu-Huan Zhuang, Jeng-Kuei Chang, Yi-Wen Sun May 2009

Electrodeposition Of Al On Magnesium Alloy In Ionic Liquid, Wen-Ta Tsai, Shu-You Chen, Mu-Huan Zhuang, Jeng-Kuei Chang, Yi-Wen Sun

Journal of Electrochemistry

Electrodeposition of a metallic aluminum on a magnesium alloy in acidic aluminum chloride-1-ethyl-3-methylimidazolium chloride ionic liquids(AlCl3-EMIC) was investigated.The effects of current density and AlCl3 content in the ionic liquid on the electrodeposition behavior were studied.The results showed that aluminum could be successfully electrodeposited on the AZ91D substrate.At-0.2 V,the ionic liquid containing 60 m/o AlCl3 was optimum for Al electrodeposition.The current efficiency was higher if electrodeposition was performed at a lower applied current density.The existence of Al coating could caused a substantial increase in open circuit potential,reducing the susceptibility of Mg alloy to corrosion.The results of electrochemical …

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Electrochemical Characteristics Of Vitaminb6 At Polybromocresol Green Modified Electrode, Jun Yao, Jiang-Yuan Li, Yang Luo May 2009

Electrochemical Characteristics Of Vitaminb6 At Polybromocresol Green Modified Electrode, Jun Yao, Jiang-Yuan Li, Yang Luo

Journal of Electrochemistry

Electrochemical characteristics of VB6 were investigated at PBG modified electrode by Cyclic voltammetry and linear sweep voltammetry.The VB6 produced an irreversible oxidation peak at 0.978 V(Vs.SCE) in HAc-NaAc(pH=4.0) buffer solution over the potential range of 0.7 to 1.2 V.The electron number,the proton number,the transfer coefficient were determined to be 1,1 and 0.37,respectively.The oxidation peak currents of VB6 versus its concentration showed a linear relationship in the concentration range of 1×10-3~2×10-5mol/L with the correlation coefficient of 0.9967 and the detection limit of 2×10-6mol/L.The recovery was 100.06%.

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Corrosion Performance Of Epoxy Coatings By Chemical Modification With Silanes, Liang Liu, Wei-Gang Ji, Ji-Ming Hu, Jian-Qing Zhang, Chu-Nan Cao May 2009

Corrosion Performance Of Epoxy Coatings By Chemical Modification With Silanes, Liang Liu, Wei-Gang Ji, Ji-Ming Hu, Jian-Qing Zhang, Chu-Nan Cao

Journal of Electrochemistry

The improvement of corrosion performance of epoxy coatings by modification with "active" and "non-active" silanes is presented."Active" silanes are defined as ones having functional groups that can react with the epoxy groups in the epoxy resin,usually amino-silanes."Non-active" silanes are defined as ones not reacting with the epoxy groups,but can react with the hydroxyl groups in the epoxy backbone by the condensation reactions under the catalysis of organic tin compounds.The FTIR results showed that both the "active" and "non-active" silanes had been successfully grafted onto the epoxy resin.Electrochemical impedance spectroscopy(EIS) and accelerated corrosion test(Machu test) showed that the corrosion performance of …

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Electrode Of Metallic Oxides Coated Titanium With Interlayer, Yi Tang, Li-Kun Xu, Yong-Lei Xin, Jun-Tao Wang, Ping Long May 2009

Electrode Of Metallic Oxides Coated Titanium With Interlayer, Yi Tang, Li-Kun Xu, Yong-Lei Xin, Jun-Tao Wang, Ping Long

Journal of Electrochemistry

Various Ti/IrRuSn,Ti/IrTa/IrRuSn and Ti/IrTaSn/IrRuSn oxide electrodes were prepared by sol-gel method.The surface morphology and microstructure were analysed with FESEM and XRD.The electrochemical activity and stability were investigated using electrochemical technologies including chlorine and oxygen evolving potential measurements,cyclic voltammetry,accelerated life test,and alternative electrolysis.The results indicate that the electrodes with interlayers present more cracks on the surface and a little bigger average grain size,with particles of different shapes precipitated in the cracks.The electroactive sites are increased and the selectivity for the chlorine evolving reaction is enhanced,but the current efficiency for the chlorine production is somewhat lowered by the addition of different interlayers.The …

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The Accelerated Test Of Simulated Atmospheric Corrosion And The Rust Evolution Of Low Carbon Steel, Jun-Hua Dong, Wei Ke May 2009

The Accelerated Test Of Simulated Atmospheric Corrosion And The Rust Evolution Of Low Carbon Steel, Jun-Hua Dong, Wei Ke

Journal of Electrochemistry

It has been set up an accelerated method of simulating to atmospheric corrosion by using wet/dry alternate test.The rust evolution rule of mass change vs time(in logarithmic coordinate) of low carbon steel under this test shows two linear sections with different slopes,in which the rust evolution transition in weight change corresponds to the compactness transition and crystallization transition during the rust layer growth.It has found that the rust evolution rule of low carbon steel in Wanning exposure site correlates to the rust evolution rule obtained by simulating the coastal atmospheric corrosion test,and the rust evolution rule of low carbon steel …

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Investigation Of Electrochemical Noise In The Crevice Corrosion Of Q235 Carbon Cteel, Qian Hu, Yu-Bing Qiu, Xing-Peng Guo May 2009

Investigation Of Electrochemical Noise In The Crevice Corrosion Of Q235 Carbon Cteel, Qian Hu, Yu-Bing Qiu, Xing-Peng Guo

Journal of Electrochemistry

The crevice corrosion behavior of Q235 carbon steels in a NaHCO3+NaCl solution was investigated by electrochemical noise(EN) and electrochemical impedance spectroscopy(EIS).Three stages of crevice corrosion including the induction,the rapid transform and the stable development could be clearly distinguished.The characteristics of the electrochemical noise and the noise resistance Rn showed remarkable differences at each stage.The electrode area ratio(r) of outside to inside the crevice had a significant influence in the development of crevice corrosion.The time of the induction stage increased with increasing r.However,under the stable development stage of the crevice corrosion,the surface outside the crevice was at an active …

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Effect Of Naphthalene Water Reducer On Corrosion Behavior Of Reinforcing Steel In Concrete, Yu-Ming Tang, Jie Zhang, Yu Zuo May 2009

Effect Of Naphthalene Water Reducer On Corrosion Behavior Of Reinforcing Steel In Concrete, Yu-Ming Tang, Jie Zhang, Yu Zuo

Journal of Electrochemistry

The influence of naphthalene water reducer on corrosion behavior of reinforcing steel in concrete was studied by the methods of corrosion potential measurement,linear polarization and EIS test.The values of concrete resistance(Rc) and polarization resistance(Rp) of the samples with naphthalene water reducer were higher than those without naphthalene water reducer,especially in the concrete with 0.2 percent naphthalene water reducer.A suitable amount of water reducer can improve the pore structures of concrete,increase the concrete compactness and impermeability,and decrease corrosion rate of rebars in concrete.

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Effect Of Electrochemical Property Of Uns J91450 Stainless Steel On Stress Corrosion Cracking In Hydrogen Sulfide Solutions, Zhi-Yong Liu, Chao-Fang Dong, Xiao-Gang Li, Li-Xian Wang May 2009

Effect Of Electrochemical Property Of Uns J91450 Stainless Steel On Stress Corrosion Cracking In Hydrogen Sulfide Solutions, Zhi-Yong Liu, Chao-Fang Dong, Xiao-Gang Li, Li-Xian Wang

Journal of Electrochemistry

Effect of electrochemical behaviours on stress corrosion cracking(SCC) of UNS J91450 stainless steel in hydrogen sulfide environment was investigated using slow-strain-rate test(SSRT) and electchemial techniques.Results show that UNS J91540 stainless steel was susceptible to SCC in varying H2S solutions,and the SCC susceptibility reduced with the increase of pH value.The electrochemical property plays an important role in the SCC occurrence,as a combined effect of hydrogen embritlement and anodic dissolution at SCC cracktip at open circuit potential.In the solution with a lower pH the hydrogen revolution was intensive and the cracktip anodic dissolution was weaker,however,in the higher pH solution the …

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Developments Of Scanning Electrochemical Probes And Their Applications In Studying Of Localized Corrosions, Chang-Jian Lin, Yan Li, Bin Lin, Rong-Gang Hu, Min Zhang, Xiang-Dong Zhuo, Rong-Gui Du May 2009

Developments Of Scanning Electrochemical Probes And Their Applications In Studying Of Localized Corrosions, Chang-Jian Lin, Yan Li, Bin Lin, Rong-Gang Hu, Min Zhang, Xiang-Dong Zhuo, Rong-Gui Du

Journal of Electrochemistry

The electrochemical inhomogeneities always exist at the interface of metal/solution,and play an important and often controlling role in localized corrosion of metals in a given environment.It is necessary to develop in situ imaging techniques for further studying the electrochemical and environmental inhomogeneities at the interface of metal/solution for the localized corrosion system.In this paper,various techniques with spatial resolution,such as scanning micro reference electrode(SMET),scanning electrochemical microscope(SECM),atomic force microscope(AFM),and scanning Kelvin probe(SKP),and their applications in corrosion studies were briefly reviewed.The chemical probes and array electrode have been developed.It was concentrated to describe our newly developed techniques of the scanning electrochemical probes,including SMET …

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Preparation And Electrochemical Properties Of Layered Manganese Oxide(Li-Birnessite Type), Xing-Kang Huang, Hai-Tao Chang, Jian-Long Gan, Qing-Shun Zhang, Hong-Jun Yue, Dong-Ping Lv, Yong Yang May 2009

Preparation And Electrochemical Properties Of Layered Manganese Oxide(Li-Birnessite Type), Xing-Kang Huang, Hai-Tao Chang, Jian-Long Gan, Qing-Shun Zhang, Hong-Jun Yue, Dong-Ping Lv, Yong Yang

Journal of Electrochemistry

Layered Li-birnessite was prepared by means of oxidizing Mn2+ with O2 gas in alkaline media.The as-prepared sample was characterized by scanning electron microscopy(SEM), X-ray diffraction(XRD), BET and thermogravimetric/diffenential thermal analysis(TG/DTA) techniques. The electrochemical properties of the material were also investigated. The results show that such a Li-birnessite consists of well-crystallized spherical particles with an interlayer distance of 0.70 nm. The Li-birnessite delivered a high discharge capacity of 203 mAh/g at a rate of 0.2 C(40 mA/g), and had good rate capability as well.

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Electrochemical Behavior Of Mg-Li Electrodes In Nacl Solution, Lin Wu, Yan-Zhuo Lv, Xue Cao, Gui-Ling Wang, Dian-Xue Cao May 2009

Electrochemical Behavior Of Mg-Li Electrodes In Nacl Solution, Lin Wu, Yan-Zhuo Lv, Xue Cao, Gui-Ling Wang, Dian-Xue Cao

Journal of Electrochemistry

The Mg-Li electrodes containing 8.5% and 14% Li were prepared using an induction melting method. Their electrochemical behavior in NaCl solution was investigated by means of potentiodynamic polarization, potentiostatic oxidation,electrochemical impedance technique and mass-loss measurements. The morphology of the electrodes after discharge was examined using scanning electron microscopy. The Mg-14Li electrode showed more negative open circuit potential and higher discharge current density than Mg-8.5Li electrode. The oxidation products of Mg-14Li loosely attached on the electrode surface and peeled off easily. The Mg-8.5Li exhibited higher utilization efficiency. Both electrodes gave higher utilization efficiencies when discharged at lower anodic potential.

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Electrochemical Performance Of The Exfoliated Graphite Containing Sulfur Cathode Material For Lithium Sulfur Battery, Ke-Guo Yuan, Wei-Kun Wang, Zhong-Bao Yu, An-Bang Wang May 2009

Electrochemical Performance Of The Exfoliated Graphite Containing Sulfur Cathode Material For Lithium Sulfur Battery, Ke-Guo Yuan, Wei-Kun Wang, Zhong-Bao Yu, An-Bang Wang

Journal of Electrochemistry

The exfoliated graphite containing sulfur cathode material was prepared by the high temperature sulfur gas diffusion adsorption method.This cathode material could obtain an initial discharge specific capacity 972 mAh·g-1,capacity retention ratio 78% and cycling efficiency above 80%,respectively.The exfoliated graphite containing sulfur cathode could decrease the reaction interphase charge transfer impedance,and restrain the sulfur or polysulfide shuttle phenomenon during the charge-discharge process through improving the diffusion impedance.

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Effects Of Kscn On Kinetic Characters Of The Positive Couple And Performance For Vanadium Redox Flow Battery, Jian-Guo Liu, Dong Shi, Yue Men, Chuan-Wei Yan May 2009

Effects Of Kscn On Kinetic Characters Of The Positive Couple And Performance For Vanadium Redox Flow Battery, Jian-Guo Liu, Dong Shi, Yue Men, Chuan-Wei Yan

Journal of Electrochemistry

In order to improve the reaction activity of VO2+/VO2+ and the battery performance of Vanadium redox flow battery,different concentration of potassium sulfocyanates KSCN were added into 0.1mol/L VOSO4/ H2SO4 solution,and the kinetic characters of electrochemical reaction of VO2+/VO2+ was studied by CV and EIS.The results showed that the addition of KSCN could improve the oxidative peak current value of positive couple VO2+/VO2+ reaction,but had little influence in the reductive peak.The addition of KSCN decreased the impedance at 1.0 V.And the value of standard rate constant k0 …

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Effect Of Impurity Cu(2+) On Oxygen Electrode In Pemfc, Xiao Jie, Jun-Bo Hou, Zhi-Gang Shao, Bao-Lian Yi May 2009

Effect Of Impurity Cu(2+) On Oxygen Electrode In Pemfc, Xiao Jie, Jun-Bo Hou, Zhi-Gang Shao, Bao-Lian Yi

Journal of Electrochemistry

Rotating disk electrode was adopted in this paper to simulate the cathode in PEMFC.In the Cu2+ electrolyte,the influence of impurity Cu2+ on Carbon-Supported Pt Catalysts was investigated by using electrochemical measurements such as chronocoulometry,cyclic voltammetry and linear sweep.Experimental results showed that,after constant voltage at 0.49 V,the ECA of Pt/C decreased dramatically,it's perhaps under potential deposition of Cu might occur on the substrate.Meanwhile the change of ORR Tafel scope reaction is very large.It might be because oxygen adsorption sites are occupied by Cu atoms after they under potential deposit on surface of Pt/C catalyst,and the adsorption of oxygen on …

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Electro-Oxidation Of Methanol On Fe-Doped Pt-Zro2/C Catalyst, Mao-Cai Lin, Dong-Dong Liu, Qing-Chun Yu, Ming-Ruo Hu, Heng-Yong Tu May 2009

Electro-Oxidation Of Methanol On Fe-Doped Pt-Zro2/C Catalyst, Mao-Cai Lin, Dong-Dong Liu, Qing-Chun Yu, Ming-Ruo Hu, Heng-Yong Tu

Journal of Electrochemistry

The Fe-doped ZrO2 powders were prepared by so-gel method.After that,Pt-Zr1-xFexO2/C catalysts were made by reducing platinum salts with ethylene glycol.The physical property of the catalyst was characterized by XRD and TEM.It was found that the distribution of the catalyst was narrow,the particle sizes of Pt and ZrO2 particles were 2~4 nm and 3~7 nm,respectively.The Cyclic Voltammetry and Chronoamperometry testing indicated that the electro-catalytic activity for methanol electro-oxidation on Pt-ZrO2/C catalyst increased when ZrO2 was doped with Fe.And Pt-Zr0.95Fe0.05O2/C catalyst showed the highest activity …

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Influence Of Nano-Al2O3 Particles In Nickel Electro-Crystallization Process, Cheng-Yu Tan, Wei Hu, Hang Cui, Yu Liu May 2009

Influence Of Nano-Al2O3 Particles In Nickel Electro-Crystallization Process, Cheng-Yu Tan, Wei Hu, Hang Cui, Yu Liu

Journal of Electrochemistry

The influence of nano-Al2O3 particles in nickel electro-deposition on copper matrix from acid sulphate solution was studied under various potentials by using cyclic voltammetry(CV) and chronoamperometry(CA).The results show that the beginning potential of electro-deposition was about-740 mV(vs.SCE) for Ni-Al2O3 solution system.With the step-potential moving to the negative direction,the nucleation time of electro-deposition for Ni-Al2O3 solution system was shortened gradually.Compared with that of pure Ni deposition system,the nucleation time tm,corresponding to the peak current of Ni-Al2O3 deposition system was apparently shortened under the lower step-potential:-740~-830 mV,which indicates that Al …

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Complex Of 3-Amino-1,2,4-Triazole And Na2Wo4 As An Inhibitor For Brass Corrosion, Qun-Jie Xu, Chun-Xiang Li, Yu-Hong Ni, Guo-Ding Zhou May 2009

Complex Of 3-Amino-1,2,4-Triazole And Na2Wo4 As An Inhibitor For Brass Corrosion, Qun-Jie Xu, Chun-Xiang Li, Yu-Hong Ni, Guo-Ding Zhou

Journal of Electrochemistry

AC impedance and polarization methods were used to study the inhibition effect of ATA and the complex of ATA and Na2WO4 for brass corrosion in 3% NaCl solution.The results indicated that ATA had inhibition effect for brass corrosion.ATA showed the best inhibition effect for brass corrosion at the ATA concentration of 7.5 mg·L-1,and the inhibition efficiency was 87.46%.At the ATA concentration of 7.5 mg·L-1 and at the Na2WO4 concentration of 0.15 mg·L-1,the complex showed optimum inhibition effect for brass corrosion,and also showed synergistic effect and the inhibition efficiency reached …

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Bs News May 2009

Bs News

Building Services Engineering

No abstract provided.

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Ole Miss Engineer 2009 Apr 2009

Ole Miss Engineer 2009

Ole Miss Engineer

No abstract provided.

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Characterizing Twin Structure And Magnetic Domain Structure Of Ni-Mn-Ga Through Atomic Force, Matthew Reinhold Apr 2009

Characterizing Twin Structure And Magnetic Domain Structure Of Ni-Mn-Ga Through Atomic Force, Matthew Reinhold

McNair Scholars Research Journal

Ni-Mn-Ga is a ferromagnetic shape memory alloy that deforms by twin boundary motion. The magneto-mechanical properties depend strongly on the twin microstructure. A thermomechanical treatment was applied to a Ni-Mn-Ga single crystal with coexisting 10M and 14M martensite structures to create twin boundaries and align the short crystallographic c direction preferentially perpendicular to the surface. The resulting twin structure was characterized using atomic force microscopy (AFM) to obtain the surface relief caused by twinning. Magnetic force microscopy (MFM) was used to find the direction of easy magnetization (which coincides with the crystallographic c direction) of each twin. Among 18 possible …

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