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Articles 361 - 390 of 402

Full-Text Articles in Computational Chemistry

Surface Chemical Properties Of Mo2C, W2C, Mo2N And W2N Probed With Co, Co2 And O2 Adsorption: A Dft Analysis, Jingyun Ye, Tianyu Zhang, Lingyun Xu, Shuxia Yin, Krishanthi Weerasinghe, Pamela Ubaldo, Ping He, Qingfeng Ge Aug 2017

Surface Chemical Properties Of Mo2C, W2C, Mo2N And W2N Probed With Co, Co2 And O2 Adsorption: A Dft Analysis, Jingyun Ye, Tianyu Zhang, Lingyun Xu, Shuxia Yin, Krishanthi Weerasinghe, Pamela Ubaldo, Ping He, Qingfeng Ge

Journal of Electrochemistry

Transition metal carbides and nitrides are attractive materials for electrodes in many electrochemical energy storage and conversion applications. In the present study, we use density functional theory slab calculations to characterize the surface chemical properties of molybdenum (Mo) and tungsten (W) carbides and nitrides, namely, Mo2C, W2C, Mo2N and W2N with the adsorption of CO, CO2 and O2. These probing molecules provide measures of in both acidity/basicity and redox property of for the surfaces of these carbides and nitrides. Our results show that Lewis basic sites were responsible for CO2 …

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Electrostatic Interactions Of Water In External Electric Field: Molecular Dynamics Simulations, Qiang Zhu, Zigui Kan, Jing Ma Aug 2017

Electrostatic Interactions Of Water In External Electric Field: Molecular Dynamics Simulations, Qiang Zhu, Zigui Kan, Jing Ma

Journal of Electrochemistry

A series of molecular dynamics simulations with or without external electric field have been carried out for a bulk water with periodic boundary condition. The difference in radial distribution function of interatomic O…O distance is subtle, with and without external electric field, except for the orientation of dipole moments of water molecules. Without the applied external electric field, distribution of the orientation angle of dipole moments is rather broad. The induced local electric field is analyzed as a function of altitude in direction of electric field. The variation of the local induced electric field is increased as the increase of …

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Dynamic Simulation Of Oxygen Reduction Reaction In Pt/C Electrode For Proton Exchange Membrane Fuel Cells, Shang Li, Fen Zhou, Lei Chen, Mu Pan Apr 2016

Dynamic Simulation Of Oxygen Reduction Reaction In Pt/C Electrode For Proton Exchange Membrane Fuel Cells, Shang Li, Fen Zhou, Lei Chen, Mu Pan

Journal of Electrochemistry

It is an urgent need to reduce the Pt loading in electrode for practical fuel cell applications worldwide. Herein, we theoretically investigate the oxygen distribution, generated current, and minimum Pt loading of Pt/C electrode for practical applications based on kinetic model of oxygen reduction reaction. The results indicate that with increasing electrode effective thickness to 40 mm, serious concentration polarization is expected for Pt/C electrode. To generate a power density of 1.4 W⋅cm-2 (2.1A⋅cm-2@0.67 V) for fuel cell, the cathode catalyst layer thickness in PEMFC should be as thin as 3 mm. The minimum Pt loading will …

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A Molecular Docking Study On Alphavirus Nsp3 Macrodomains, B. Danger Davies Jan 2016

A Molecular Docking Study On Alphavirus Nsp3 Macrodomains, B. Danger Davies

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

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Electrochemical Catalysis: A Dft Study, Li Li, Zi-Dong Wei Aug 2014

Electrochemical Catalysis: A Dft Study, Li Li, Zi-Dong Wei

Journal of Electrochemistry

In this review, we focus on achievements in electro-catalysis based on the density function theory study. The relationships among the electrode potential, electronic structure of catalysts and electro-catalytic activity are summarized in three parts: the adsorption and desorption of species, electron transfer, and stability of catalysts. The electrode potential and the electronic structure (d-band center or Fermi (HOMO) energy) of catalysts significantly influence the formation, adsorption and desorption of surface species on electrode. The electro-catalytic activity can be improved by modulating the electrode potential and electronic structure of catalysts.

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Effects Of Oxygen Coverage And Hydrated Proton Model On The Dft Calculation Of Oxygen Reduction Pathways On The Pt(111) Surface, Li-Hui Ou, Sheng-Li Chen Jun 2014

Effects Of Oxygen Coverage And Hydrated Proton Model On The Dft Calculation Of Oxygen Reduction Pathways On The Pt(111) Surface, Li-Hui Ou, Sheng-Li Chen

Journal of Electrochemistry

DFT calculation is used to study various possible steps in the oxygen reduction reaction (ORR), including the adsorption and dissociation process of O2 and the serial protonation process of dissociated products to form H2O on the Pt(111) surface. By using slabs of different sizes, and different numbers of pre-adsorbed oxygen atoms, the coverage effects on the pathways are investigated. The calculated results using different hydrated proton models are also compared. It is shown that the initial step of the ORR is the formation of a protonated end-on chemisorbed state of OOH*, which can transform to an unprotonated …

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A Dft Calculation Screening Of Pt-Based Bimetallic Catalysts For Oxygen Reduction, Li-Hui Ou, Sheng-Li Chen Feb 2013

A Dft Calculation Screening Of Pt-Based Bimetallic Catalysts For Oxygen Reduction, Li-Hui Ou, Sheng-Li Chen

Journal of Electrochemistry

Developing Pt-lean catalysts for oxygen reduction reaction (ORR) is the key for large-scale application of proton exchange membrane fuel cell (PEMFC). In this paper, we have proposed a multiple-descriptor strategy for screening efficient and durable ORR alloy catalysts of low Pt content. We argue that an ideal Pt-based bimetallic alloy catalyst for ORR should possess simultaneously negative alloy formation energy, negative surface segregation energy of Pt and a lower oxygen binding ability than pure Pt. By performing detailed DFT calculations on the thermodynamics, surface chemistry and electronic properties of various Pt-M alloys (M refers to non-precious transition metals in the …

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A New Random Walk Simulation Model For Study Of Diffusion Behavior Of Single Particle Within Two-Dimensional Space, Jianwei Zhao, Lili Chen, Yingqiang Fu, Shaohong Li, Tiannan Chen, Shijie Zhang Oct 2012

A New Random Walk Simulation Model For Study Of Diffusion Behavior Of Single Particle Within Two-Dimensional Space, Jianwei Zhao, Lili Chen, Yingqiang Fu, Shaohong Li, Tiannan Chen, Shijie Zhang

Journal of Electrochemistry

Research on diffusion behaviors is of significant value in that it is closely related to transport phenomena in micro-chemistry. However, the effects of variables on diffusion are still unclear. Here, we developed and programmed a simulation methodology along with data analysis, which was capable to simulate the diffusion of a particle within twodimensional heterogeneous space in large timescale; the effects of periodically arranged impenetrable barriers of specific shape and lateral drifting velocity on diffusion behavior were studied. As well as standard mean square displacement analysis, a new method, the appearance probability distribution method, was introduced, which revealed whether the particle …

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Identification Of Persistent Long Range Interactions In GA95 And GB95 Through Thermal Unfolding Simulations, Milen Redai Tesfamariam Jul 2012

Identification Of Persistent Long Range Interactions In GA95 And GB95 Through Thermal Unfolding Simulations, Milen Redai Tesfamariam

Chemistry & Biochemistry Theses & Dissertations

For over five decades, different experiments have been performed to research how proteins attain their native three dimensional structures. However, the folding problem continues to be a puzzle in modern science. The design of two proteins that have maximal sequence identity but different folds and functions is one method that is being used to study the relationship between protein structure and amino acid sequence. In particular, mutant proteins of Streptococcus protein G, GA and GB, have 95% sequence identity and a 3a helix fold and β4/a fold, respectively. Molecular dynamics simulations of GA95 …

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Application Of First Principles Calculations In Anode Materials For Lithium Ion Batteries, Tian-Ran Zhang, Dai-Xin Li, Si-Qi Yang, Zhan-Liang Tao, Jun Chen Jun 2012

Application Of First Principles Calculations In Anode Materials For Lithium Ion Batteries, Tian-Ran Zhang, Dai-Xin Li, Si-Qi Yang, Zhan-Liang Tao, Jun Chen

Journal of Electrochemistry

First principles calculations play an important role in the study and development of new materials for lithium batteries. In this paper, we review the application of first principles calculations in the design of anode materials, including the modeling of the interaction of lithium in the anode materials, capacity, voltage, electrochemical reaction process, diffusion, rate capability, the relationship between the structure and properties, and the experimental phenomena interpreting. Based on the discussions, we emphasize on the importance of first principles calculations and demonstrate their requirement for further development.

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Cloning And Characterization Of Sas0754, A Hypothetical Protein From Community Associated Staphylococcus Aureus, Unknown Unknown May 2012

Cloning And Characterization Of Sas0754, A Hypothetical Protein From Community Associated Staphylococcus Aureus, Unknown Unknown

Symposium 2012

Community associated Staphylococcus aureus (strain MSSA476) is a gram positive cocci capable of infecting many different parts of the body and known to cause serious infections that can be fatal, such as bacterial arthritis and acute endocarditis. To find effective ways of fighting against CA-MRSA strains we must learn more about their ability to infect. The focus of this study was cloning and characterization of a protein referred to as SAS0754. The size of SAS0754 is 340 amino acids and the gene sequence is 1023 nucleotides. The hypothetical function of this protein is that it is an extracellular matrix binding …

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A Convenient Synthesis Of 2,6-Dichlorohomonicotinic Acid, Chase Buchanan, Richard W. Fitch May 2012

A Convenient Synthesis Of 2,6-Dichlorohomonicotinic Acid, Chase Buchanan, Richard W. Fitch

Symposium 2012

In our synthetic efforts toward the alkaloid phantasmidine, we required a convenient source of the title compound. Herein, we describe a short synthesis of 2,6-dichlorohomonicotinic acid by direct allylation of 2,6-dichloropyridine with LDA/allyl chloride, followed by permanganate oxidation of the side chain [figure1]. Yields for the allylation are high, while permanganate oxidation required more adjustment. Successful conditions require the modest acidification of the mixture with acetic acid and cleanup by acid base workup. No chromatography is needed.

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Convenient Parallel Synthesis Of Alkyl- And Aryl-S-Tert-Butyl Thiothers, Rebecca Norcross, Jessica Stanfield, Richard W. Fitch May 2012

Convenient Parallel Synthesis Of Alkyl- And Aryl-S-Tert-Butyl Thiothers, Rebecca Norcross, Jessica Stanfield, Richard W. Fitch

Symposium 2012

While preparing novel cysteine derivatives as oxidation catalysts, we needed S-tert-butylcysteine. We also examined acid-promoted tert-butylation of thiols using tert-butanol as reagent and solvent. While cysteine and aminoethanethiol work well using tBuOH in 4M HCl, other thiols fail in the aqueous environment and aerobic conditions. We examined a variety of aliphatic and aromatic thiols in tBuOH with H2SO4 catalysis and found that argon sparging and the use of 1 eq of acid led to good yields in a parallel format.

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Dft Study Of Co2 Reduction To Hydrocarbons On Cu Surfaces, Li-Hui Ou, Sheng-Li Chen May 2011

Dft Study Of Co2 Reduction To Hydrocarbons On Cu Surfaces, Li-Hui Ou, Sheng-Li Chen

Journal of Electrochemistry

CO2 reduction on Cu(111) single crystal surfaces was studied using DFT calculations on the reaction energies and the minimum energy paths. The results indicated that the possible reaction paths for CO2 reduction on Cu(111) surface are CO2(g) + H* → COOH* → (CO +OH)*, (CO + H)* → CHO*, CHO + H → CH2O* → (CH2+O)*, CH2* + 2H* → CH4 or 2CH2* → C2H4. On Cu(111) surface, the reaction rate is controlled by steps of CH2O* → (CH2 …

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Diffusion And Random Walks, Lewis Ludwig, Annabel Edwards Jan 2011

Diffusion And Random Walks, Lewis Ludwig, Annabel Edwards

Faculty Publications

No abstract provided.

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Electrochemical Behaviors Of Organic Coating/Matal Substrate Under Simulated Deep Sea Environment Partⅰ.Effects Of Seawater Pressure On Transportation Behavior Of Water Through Coating And Coating′S Protective Performance, Bin Liu, Zhi-Gang Fang, Tao Wang, Hong-Bin Wang Nov 2010

Electrochemical Behaviors Of Organic Coating/Matal Substrate Under Simulated Deep Sea Environment Partⅰ.Effects Of Seawater Pressure On Transportation Behavior Of Water Through Coating And Coating′S Protective Performance, Bin Liu, Zhi-Gang Fang, Tao Wang, Hong-Bin Wang

Journal of Electrochemistry

By means of electrochemical impedance spectroscopy(EIS),the electrochemical behaviors of organic coating/metal substrate were studied under simulated deep sea environment in the laboratory.Effects of seawater pressure on the transportation behavior of water through coating and the protective performance of coating were analyzed.The experimental results showed that,compared to normal pressured seawater,there were different impedance characteristics of coating in 3.5 MPa pressured seawater.The main observations were that high seawater pressure accelerated the process of water uptake and invalidation of coating,increased water absorption,and lowered the anti-corrosion property of coating.

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Initial Stage Of Atmospheric Corrosion Of Ndfeb(M35) In A Simulated Marine Atmosphere, Chun-Ling Li, Yuan-Tai Ma, Ying Li, Fu-Hui Wang Nov 2010

Initial Stage Of Atmospheric Corrosion Of Ndfeb(M35) In A Simulated Marine Atmosphere, Chun-Ling Li, Yuan-Tai Ma, Ying Li, Fu-Hui Wang

Journal of Electrochemistry

This study detailed the atmospheric corrosion behaviour of sintered NdFeB(M35) in a simulated marine atmosphere with 80% relative humidity(RH).The dissolution and subsequent reaction of NaCl particles cause the attack of NdFeB.The corrosion presented three representative types:if the electrolyte covered magnetic phase and Nd-rich phase,the Nd-rich phase was corroded firstly due to galvanic effect;if the electrolyte covered magnetic phase,magnetic phase was corroded along the grain boundary;if the electrolyte located near the position of defects,corrosion progressed along with the defect because of low concentration of oxygen inside the defect.With corrosion progressing,local corrosion areas were mutually connected,with Nd-rich phase and grain boundary being …

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Comparative Studies On The Deterioration Process Of Organic Coatings Under Immersed And Cyclic Wet-Dry Conditions By Eis, Yu-Nan Li, Jia Wang, Wei Zhang Nov 2010

Comparative Studies On The Deterioration Process Of Organic Coatings Under Immersed And Cyclic Wet-Dry Conditions By Eis, Yu-Nan Li, Jia Wang, Wei Zhang

Journal of Electrochemistry

Under the immersed and wet-dry cyclic conditions,the deterioration processes of the organic coatings on carbon steel surface have been comparatively studied by using electrochemical techniques.The wet-dry cycles were carried out in the alternating conditions of 12 h by immersing in a 3.5% sodium chloride solution and drying at 25 ℃ and 50% RH.Coating resistance,Rf,coating capacitance,Cf,and double layer capacitance,Cd,were monitored continuously and separately under above two conditions.The percentages of the intenfacial active area,Aw,were estimated from the obtained double layer capacitance,Cd.According to the EIS characteristics,the entire deterioration processes under above two mentioned conditions can be divided into three main stages,consisting of the …

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Eis Study On The Change Of Resistance And Water Absorption During The Failure Graduation Of Inorganic Zinc-Rich/Epoxy/Aliphatic Polyurethane Composite Coatings, Shao-Ping He, Jin-Ping Xiong, Yu-Ming Tang, Yu Zuo Nov 2010

Eis Study On The Change Of Resistance And Water Absorption During The Failure Graduation Of Inorganic Zinc-Rich/Epoxy/Aliphatic Polyurethane Composite Coatings, Shao-Ping He, Jin-Ping Xiong, Yu-Ming Tang, Yu Zuo

Journal of Electrochemistry

The failure process of inorganic zinc-rich/micaceous iron oxide epoxy/aliphatic polyurethane composite coatings in 3.5% NaCl solution under ultraviolet radiation(UV) was studied with Electrochemical Impedance Spectroscopy(EIS).The result shows that the protective property of the coating was enhanced with the increase of total coating thickness,but the degree of improvement reduced gradully as the coating thickness increased.The shielding effect of the micaceous iron oxide epoxy was mainly reflected in the initial period of the service process,while in later period the coating performance largely depended on the zinc-rich primer.The change of the water uptake in the composite coating presented a 'three-stage' characteristic.The thinner the …

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Measurement And Wavelet Analysis Of The Electrochemical Noise Of Rebar Steel In Simulated Concrete Pore Solution, Rong-Gang Hu, Chen-Qing Ye, Shi-Gang Dong, Chang-Jian Lin May 2010

Measurement And Wavelet Analysis Of The Electrochemical Noise Of Rebar Steel In Simulated Concrete Pore Solution, Rong-Gang Hu, Chen-Qing Ye, Shi-Gang Dong, Chang-Jian Lin

Journal of Electrochemistry

Electrochemical noise (ECN) measurement can provide information about both corrosion rate and corrosion type while inflicting no perturbation on the studied system. The ECN data of steel rebar in SPS with different amount of Cl-were collected and treated by discrete wavelet transformation to evaluate the contribution from transients in different frequency in the overall signals. Energy distribution plot (EDP) indicated in SPS with 0.0001 mol/L NaCl, the transients with time constant between 16 ～ 32 s were found to be predominant over other processes; while in SPS with higher Cl-concentration, the trend toward active corrosion became the main process. It …

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Monte Carlo Simulation Of Kinetics Of Phenol Degradation On Titanium Based Anode, Xing-Fang Zhang, Zhen-Hai Liang, Wen-Ping Shi, Cai-Mei Fan Aug 2009

Monte Carlo Simulation Of Kinetics Of Phenol Degradation On Titanium Based Anode, Xing-Fang Zhang, Zhen-Hai Liang, Wen-Ping Shi, Cai-Mei Fan

Journal of Electrochemistry

According to Monte Carlo mechanism and random process theory,the mechanism of phenol degradation on titanium electrode was simulated. The effects of degradation time,initial concentration of phenol,electrode performance and intermediates on the process of degradation were determined. The results indicated that the phenol concentration is decreasing and becoming steady during the degradation process,if increase the initial concentration,the degradation rate is also increased at the beginning of reaction process,the electrodes with high performance strongly affect the first step of degradation by reducing the residence time of intermediates,the whole process and the productions of second step are primarily controlled by the first step …

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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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Corrosion Electrochemical Behavior Of Az31 And Az61 Magnesium Alloys In Simulated Sea Water, Ling-Jie Li, Sheng-Hai Yu, Jing-Lei Lei, Chuan-Pu Liu, Sheng-Tao Zhang, Fu-Sheng Pan Feb 2008

Corrosion Electrochemical Behavior Of Az31 And Az61 Magnesium Alloys In Simulated Sea Water, Ling-Jie Li, Sheng-Hai Yu, Jing-Lei Lei, Chuan-Pu Liu, Sheng-Tao Zhang, Fu-Sheng Pan

Journal of Electrochemistry

Tafel polarization curves and electrochemical impedance spectroscopy(EIS) techniques were employed to investigate the corrosion electrochemical behavior of AZ31 and AZ61 magnesium alloys.Scanning electron microscopy(SEM) was used to observe the alloy microstructure and corrosion morphology.The variation of the bulk corrosive medium pH with immersion time was recorded during the exposure of the alloys to simulated sea water.Results show that AZ61 magnesium alloy exhibits much better anti-corrosion ability than AZ31 magnesium alloy.The different corrosion behavior between the two magnesium alloys is correlated with their different content of Al alloying element.The higher content of Al in AZ61 alloy leads to the homogenerous microstructure …

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Inhibition Mechanism Of Imidazoline Derivate In Simulated Water From Deep Gaswell Containing Co2, Yuan Lu, He-Xia Liu, Jing-Mao Zhao Aug 2007

Inhibition Mechanism Of Imidazoline Derivate In Simulated Water From Deep Gaswell Containing Co2, Yuan Lu, He-Xia Liu, Jing-Mao Zhao

Journal of Electrochemistry

The electrochemical method and atomic force microscope(AFM) were applied to study the inhibition mechanism of Im-D,an imidazoline derivate inhibitor,for mild steel in CO2 saturated solution.The imidazoline derivate can inhibit effectively CO2 corrosion,make the steel surface smoother and belongs to the anodic controlled mixed-type inhibitor.Its adsorption on the surface of mild steel is a spontaneous and exothermic process accompanied by the decrease of entropy and follows the Langmuir adsorption isothermal equation.The lower temperature will facilitate the process.The changes in the apparent activation energy(Ea) and the pre-exponential factor(A) of the corrosion reaction before and after the addition of inhibitor were …

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Simulation Of A Packed-Bed Electrochemical Reactor With Cooled Cathode For Continuously Producing Glyoxylic Acid By Oxalic Acid, Qing-Biao Li, Xiao-Hui Hu, Xue-Yun Chen, Wei Li, Yu-Zhong Su, Jun Li May 2007

Simulation Of A Packed-Bed Electrochemical Reactor With Cooled Cathode For Continuously Producing Glyoxylic Acid By Oxalic Acid, Qing-Biao Li, Xiao-Hui Hu, Xue-Yun Chen, Wei Li, Yu-Zhong Su, Jun Li

Journal of Electrochemistry

Oxalic acid electrochemical reduction has been suggested as an important technology to produce glyoxylic acid;the packed-bed electrochemical reactor with cooled cathode(PERCC)has been proposed to solve the problem of lower space-time-yield that appeared in the parallel electrode reactor.Based on the mass balance equations,charge balance equations and kinetics equations of the system,a two-dimensional reactor model was established to describe the continuous operation process for producing glyoxylic acid from oxalic acid by PERCC.Using the orthogonal collocation method,the model equations could be numerically solved,and the glyoxylic concentration along the reactor length could be simulated.The modeling results indicated that the glyoxylic concentration increased quickly at …

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Computational Models To Predict The Inhibition Of Cytochrome P450 3a4 By Selected Natural Compounds, Sushma Thotakura Jan 2007

Computational Models To Predict The Inhibition Of Cytochrome P450 3a4 By Selected Natural Compounds, Sushma Thotakura

Theses and Dissertations

Cytochrome P450 3A4 (CYP3A4) plays a pivotal role in the metabolism of xenobiotics. Methylenedioxobenzene containing natural products have been shown to inhibit CYP3A4. Given that these compounds are widely distributed in nature there is a strong potential for drug interaction with many plants used for dietary or medicinal purposes. In this research we have developed two different computational models (Comparative Molecular Field Model and Artificial Neural Network Model) to assist in the identification of potentially strong inhibitors that could be further studied for potential inhibitory effects. These models were used to screen for the CYP3A4 inhibitory effects of 100 naturally …

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Study On The Electrochemical Impedance Spectroscopy (Eis) Of Al-Bronze At Different Anodic Potentials, Hui Yu, Sa-Ying Dong, Hai-Bo Xu, Ming-Xian Sun Feb 2004

Study On The Electrochemical Impedance Spectroscopy (Eis) Of Al-Bronze At Different Anodic Potentials, Hui Yu, Sa-Ying Dong, Hai-Bo Xu, Ming-Xian Sun

Journal of Electrochemistry

The corrosion dissolution mechanism of Al-bronze has been investigated by Electrochemical Impedance Spectroscopy (EIS) at different anodic potentials. In the active region, the corrosion products are complex compounds of cupreous chloride and the diffusion of CuCl2- is the control process of electrochemical reaction. In the transition region, there exhibits two capacitance loops on EIS because CuCl and cupreous oxides films deposit on the electrode surface. In the limiting current region, an inductance loop appears on the EIS because the breakdown of the oxides film leads to serious pit corrosion.

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Electronic Structures And Geometries Of Lial, Liang-Gen Wu, Rong-Qin Wu, Li-Juan Chen, Zi-Zhong Zhu, Yong Yang Nov 2003

Electronic Structures And Geometries Of Lial, Liang-Gen Wu, Rong-Qin Wu, Li-Juan Chen, Zi-Zhong Zhu, Yong Yang

Journal of Electrochemistry

LiAl is an important anode material for lithium batteries. Based on the plane-wave method and first-principles pseudopotentials, the electronic and geometric properties of LiAl have been studied. The cohesive energies versus volumes of unit cell, energy band structures, electronic density of states and charge density distributions of LiAl under some important structures are presented. The reason of B32-structure as the ground-state of LiAl crystal has also been elucidated, which is owing to Al-Al atoms in B32-structure form strong diamond-type covalent bonds. The present theoretical ground state structure of LiAl is consistent with the experimental and other theoretical results.

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Corrosion Behavior Of Reinforcing Steel In Concrete Subjected To Chloride Contamination By Eis, Rong-Gang Hu, Rong-Gui Du, Chang-Jian Lin May 2003

Corrosion Behavior Of Reinforcing Steel In Concrete Subjected To Chloride Contamination By Eis, Rong-Gang Hu, Rong-Gui Du, Chang-Jian Lin

Journal of Electrochemistry

Electrochemical impedance spectroscopy(EIS) was employed to study the influence of chloride on the corrosion behavior of reinforcing steel in concrete. In Nyquist plot, the spectrum consists of two semicircles, indicating that the reinforced concrete system contained two time constants,one derived from electrical double layer of reinforcing steel and the other from the deposition film of concrete layer. The depressed semicircle in lower frequency featured the non-faradic behavior of the electrical double layer (EDL) deviated from idea capacitor due to diffusive effect which was attributed to the surface roughness of rebar and the inhomogenity of concrete layer. Then the EDL was …

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Steady State Simulation Of Ysz Intermediate-Temperature Fuel Cell, Zi-Jing Lin, Ye Gu, Xiao-Hua Zhang Nov 2002

Steady State Simulation Of Ysz Intermediate-Temperature Fuel Cell, Zi-Jing Lin, Ye Gu, Xiao-Hua Zhang

Journal of Electrochemistry

With a coupled 2D electrochemical and thermal modeling software, the characteristics of the steady state operation of the intermediate-temperature fuel cell with thin yttria-stabilized zirconia(YSZ) electrolyte was analyzed. The parameters of I-V equation were obtained from fitting the experiment results and the choice of grid points was determined by balancing the accuracy requirement and computational efficiency. The temperature fields at different operation circumstances such as flow designs, material choices for interconnect, were examined. The dependences of the output power and cell efficiency on the operating voltage at different temperatures were studied. Based upon the analysis of the temperature profile, it …

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