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Full-Text Articles in Engineering

Varying Current Electro-Synthesis Of Glyoxalic Acid In Pairs In The Fixed-Bed Electrolytic Cell, Yin Sheng Chen, Xin Sheng Zhang, Ying Chun Dai, Wei Kang Yuan Feb 2002

Varying Current Electro-Synthesis Of Glyoxalic Acid In Pairs In The Fixed-Bed Electrolytic Cell, Yin Sheng Chen, Xin Sheng Zhang, Ying Chun Dai, Wei Kang Yuan

Journal of Electrochemistry

As for the process of the electro oxidation of glyoxal to glyoxalic acid, the electrolytic result of either fixed bed electrolytic cell or varying current electrolysis was better than that of either flat plate electrolytic cell or constant current electrolysis. The average current density of varying current electro synthesis of glyoxalic acid in pairs was 1535 A/m 2 and the current efficiency were 85.3% and 86.7% and the selectivity were 93.9% and 94.0% for the anodic oxidation and cathodal reduction respectively. The initial composition of anodic electrolyte was 7% glyoxal and 8% hydrochloric acid (W/W) and the cathodal electrolyte consisted …


Electrochemical Synthesis And Characterization Of The Nickel Electropolyurushiol Coordination Polymer, Feng Gao, Guo-Cai Shen, Jie-Yuan Tang, Wen-Gong Zhang Feb 2002

Electrochemical Synthesis And Characterization Of The Nickel Electropolyurushiol Coordination Polymer, Feng Gao, Guo-Cai Shen, Jie-Yuan Tang, Wen-Gong Zhang

Journal of Electrochemistry

The nickel electropolyurushiol coordination polymer(EPU Ni 2+ ) was obtained by the reaction between nickel chloride isopropyl alcohol solution with electropolyurushiol (EPU).The electrochemical polymerization of urushiol and the preparation of nickel electropolyurushiol coordination polymer were investigated.The coordination polymer was characterized by XPS,FT_IR,DMTA and AES methods,and its composition and structure were determined.The content of Ni 2+ reached up to 7.5%. It was shown that there was certain coordination between Ni 2+ and electropolyurushiol in the coordination polymer,thus cross_links were formed.Therefore the glass transition temperature of the coordination polymer increased and heat resistance was enhanced considerably.


Effect Of The Brightener On The Behavior Of The Silver Electrodeposition, Jin Hu, Hui-Min Wu, Xiang-Ming Feng, Wei-Dong Li, Zheng-Zhong Zuo, Yun-Hong Zhou Feb 2002

Effect Of The Brightener On The Behavior Of The Silver Electrodeposition, Jin Hu, Hui-Min Wu, Xiang-Ming Feng, Wei-Dong Li, Zheng-Zhong Zuo, Yun-Hong Zhou

Journal of Electrochemistry

The effect of the brightener on the behavior of the silver electrodeposition in cyanide solution was studied by potentiostatically step and rotating dise electrode(RDE) as well as X_ray diffraction (XRD) and scanning electron microscope (SEM).It was found that the silver electrodeposition was not changed by the addition of the brightener to the fundarmental solution.But it apparently increased the solution's micro_leveling effection and remarkably improved the coating's surface lightness.The coating's orientation isn't changed by the addition of the brightener in the light of the XRD result.The effectivness of the brightener was also discussed by the half_wideth of the XRD.


Further Evidence For Surface Properties Of Porous Silicon Resulting In Electroluminescence, Zhan-Jun Zhang, Bin Wu, Jing-Jian Li, Zhong-Fan Liu, Sheng-Min Cai Feb 2002

Further Evidence For Surface Properties Of Porous Silicon Resulting In Electroluminescence, Zhan-Jun Zhang, Bin Wu, Jing-Jian Li, Zhong-Fan Liu, Sheng-Min Cai

Journal of Electrochemistry

The electroluminescence of porous silicon in solutions at positive biases was investigated by luminescence spectrometer. The electroluminescence of porous silicon in solutions mainly depended on its surface properties. The elelctroluminescence was much enhanced when the sample of porous silicon was electrolyzed once again which had undergone an electroluminescence test. The tests of both cyclic voltammetry and the luminescence of the sample of porous silicon prepared by repeated electrolysis provided further evidence that the electroluminescence of porous silicon in solutions at positive biases stemmed from the oxidation of Si_H on the surface of porous silicon. The voltage tunable emitting for porous …


Determination Of Copper In The Waste Water Of Plating By Chronocoulometry For Flowing Solution, Xin-Hua Lin, Wei Chen Feb 2002

Determination Of Copper In The Waste Water Of Plating By Chronocoulometry For Flowing Solution, Xin-Hua Lin, Wei Chen

Journal of Electrochemistry

The chronocoulometry for flowing solution was devoloped and applied to the detemination of copper(Ⅱ) in the waste water of plating.The linear range of copper(Ⅱ) was 2~16mg/L,and the relative standard deviation was less than 0.1% ( n =8).The recovery was 98%~103% for copper(Ⅱ) in the waste water.Chronocoulometry for flowing solution overcomed noise disturbance resulting from capacity current and variety of property of electrode surface.This method was sensitive,accurate and well reproducible.


Study On The Orthogonal Test Of Al-Substituted Α-Ni(Oh)_2 Prepared By Complexation-Precipitation Method, Hui Chen, Jian-Ming Wang, Tao Pan, Hui-Ming Xiao, Jian-Qing Zhang Feb 2002

Study On The Orthogonal Test Of Al-Substituted Α-Ni(Oh)_2 Prepared By Complexation-Precipitation Method, Hui Chen, Jian-Ming Wang, Tao Pan, Hui-Ming Xiao, Jian-Qing Zhang

Journal of Electrochemistry

Al_substituted α_Ni(OH) 2 was prepared by a complexation_precipitation method and characterized by XRD.The electrochemical performance was tested by the charge_discharge method.The experimental results of orthogonal test showed that the effect order of some key preparative conditions on the electrochemical performance of Al_substituted α_Ni(OH) 2 was the concentration of aqueous ammonia,the content of aluminum and pH value.The optimum prepareative conditions for obtaining the sample with maximum specific discharge capacity(304 mAh·g -1 ) were 0.5 mol·L -1 aqueous ammonia,15 mol% Al content and pH 11.0.


The Determination Of The Best Modified Way And Microscopical Analysis For Enzyme/Immunoelectrodes, Sa-Ying Dong, Hong-Ren Wang, Yu-Zhu Gao, Guang-Zhang Chen, Ming-Xiang Lv, Bo-Yi Tian Feb 2002

The Determination Of The Best Modified Way And Microscopical Analysis For Enzyme/Immunoelectrodes, Sa-Ying Dong, Hong-Ren Wang, Yu-Zhu Gao, Guang-Zhang Chen, Ming-Xiang Lv, Bo-Yi Tian

Journal of Electrochemistry

In this paper,the electrochemical response characteristics of enzyme and immuno electrodes were studied by cyclic voltammetry under different conditions. Our goals were to determine the best modified way of bioelectrode,which was the base of biosensor's application. 30U GOD and 0.8 mg/mL SEC1 antibody were suitable to bioelectrode preparation and detection. The microscopical analysis was finished with scan microscopy.


Preliminary Study On Direct Ethanol Fuel Cell, Shu-Qin Song, Li-Kang Chen, Jian-Guo Liu, Zhao-Bin Wei, Qin Xin Feb 2002

Preliminary Study On Direct Ethanol Fuel Cell, Shu-Qin Song, Li-Kang Chen, Jian-Guo Liu, Zhao-Bin Wei, Qin Xin

Journal of Electrochemistry

The performance of a direct ethanol fuel cell based on Nafion115 was reported.PtRu/C and Pt/C were used as ethanol anode and oxygen cathode catalysts in a single cell of size 9 cm 2 .The effects of temperature,oxygen pressure,the flow rate of ethanol, and oxygen, and ethanol concentration were tentatively studied.The experimental results showed that the cell open circuit voltage 0.608 V,the cell voltage 0.329 V at 50 mA/cm 2 ,and the peak power density 19.25 mW/cm 2 were reached under the conditions of T cell =85 ℃, P O2 =0.5 MPa, C ethanol =1.0 mol/L and with the flow rate …


Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics: Quarterly Progress Report 11/16/01- 2/15/02, Samir Moujaes, Yitung Chen Feb 2002

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics: Quarterly Progress Report 11/16/01- 2/15/02, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The Lead-Bismuth eutectic (LBE) has been determined from previous experimental studies by the Russians and the European scientific community to be a potential material that can be used as a spallation target and coolant for the AAA proposed application.

Properly controlling the oxygen content in LBE can drastically reduce the LBE corrosion to structural steels. However, existing knowledge of material corrosion performance was obtained from point-wise testing with very limited density. The transport of oxygen and corrosion products, their interaction and variation of corrosion/precipitation along the flow are not well understood.

The first subtask of this project involves using a …


Hydrogen-Induced Embrittlement Of Candidate Target Materials For Applications In Spallation-Neutron-Target Systems, Ajit K. Roy, Brendan O'Toole Feb 2002

Hydrogen-Induced Embrittlement Of Candidate Target Materials For Applications In Spallation-Neutron-Target Systems, Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The purpose of this project is to evaluate the effect of hydrogen on cracking of candidate target materials for applications in spallation-neutron-target (SNT) systems such as accelerator production of tritium (APT) and accelerator transmutation of waste (ATW). The test materials will undergo appropriate thermal treatments prior to being hydrogen-charged by potentiostatic cathodic polarization technique in a simulated aqueous environment at different temperatures of interest. The specimens, upon completion of testing, will be metallographically examined. Further, the scanning electron microscopy (SEM) will be used to determine the extent and nature of cracking in the specimens tested. The thrust of the proposed …


Low-Cost Manufacturing Process For Nanostructured Metals And Alloys, Travis L. Brown, Srinivasan Swaminathan, Srinivasan Chandrasekar, W. Dale Compton, Alexander H. King, Kevin P. Trumble Jan 2002

Low-Cost Manufacturing Process For Nanostructured Metals And Alloys, Travis L. Brown, Srinivasan Swaminathan, Srinivasan Chandrasekar, W. Dale Compton, Alexander H. King, Kevin P. Trumble

Alexander H. King

In spite of their interesting properties, nanostructured materials have found limited uses because of the cost of preparation and the limited range of materials that can be synthesized. It has been shown that most of these limitations can be overcome by subjecting a material to large-scale deformation, as occurs during common machining operations. The chips produced during lathe machining of a variety of pure metals, steels, and other alloys are shown to be nanostructured with grain (crystal) sizes between 100 and 800 nm. The hardness of the chips is found to be significantly greater than that of the bulk material.


Experimental Investigation Of Steel Corrosion In Lead Bismuth Eutectic (Lbe): Characterization, Species Identification, And Chemical Reactions, John Farley, Dale L. Perry, Allen L. Johnson Jan 2002

Experimental Investigation Of Steel Corrosion In Lead Bismuth Eutectic (Lbe): Characterization, Species Identification, And Chemical Reactions, John Farley, Dale L. Perry, Allen L. Johnson

Transmutation Sciences Materials (TRP)

The goal of the present research is to achieve a basic understanding of corrosion of steels by Lead Bismuth Eutectic (LBE). Liquid LBE is under consideration in the transmuter as both a spallation target and as a blanket coolant. There have been previous studies of LBE, especially by the Russians, who have over 80 reactor-years experience with LBE coolant in their Alpha-class submarine reactors. However, a fundamental understanding and verification of its role in the corrosion of steels is still very incomplete. We have begun a program of post-experiment testing and analysis on steel samples that have been in intimate …


Corrosion Of Steel By Lead Bismuth Eutectic, John Farley, Dale L. Perry, Allen L. Johnson Jan 2002

Corrosion Of Steel By Lead Bismuth Eutectic, John Farley, Dale L. Perry, Allen L. Johnson

Transmutation Sciences Materials (TRP)

This research program will analyze various steel samples that have been exposed to LBE as part of the national program to develop LBE and transmutation technologies. This information will be paramount in developing engineering efforts to control, avoid, and/or minimize the effect of corrosion of steels by LBE in transmuter and LBE systems. Additionally, this program provides UNLV researchers with hands-on experience that will be crucial in developing the UNLV LBE program, supporting the University’s mission with the ISTC target complex, and the future development of additional facilities to examine LBE systems.

The research group plans to test the hypothesis …


Corrosion Of Steel By Lead Bismuth Eutectic: Year 1 Annual Report, John Farley Jan 2002

Corrosion Of Steel By Lead Bismuth Eutectic: Year 1 Annual Report, John Farley

Transmutation Sciences Materials (TRP)

The goal is to investigate the corrosion of stainless steel by lead-bismuth eutectic (LBE), which has been proposed for use as a blanket coolant and a spallation target in the transmuter.


Hydrogen-Induced Embrittlement Of Candidate Target Materials For Applications In Spallation-Neutron-Target Systems, Ajit K. Roy, Brendan O'Toole, Zhiyong Wang, David W. Hatchett Jan 2002

Hydrogen-Induced Embrittlement Of Candidate Target Materials For Applications In Spallation-Neutron-Target Systems, Ajit K. Roy, Brendan O'Toole, Zhiyong Wang, David W. Hatchett

Transmutation Sciences Materials (TRP)

Spallation-neutron-sources, such as those under investigation for use in accelerator-driven transmutation systems, generate neutrons through the collision of high-energy protons, or charged hydrogen atoms, with heavy metal targets such as lead. As a result, these systems also tend to deposit a significant amount of hydrogen in the materials of the transmuter target and superstructure. This can result in accelerated corrosion and changes in the properties of the exposed materials. Of particular importance is a phenomenon called hydrogen embrittlement, in which materials lose their ductility (ability to deform under stress) and become brittle (more susceptible to fracture) after reacting with hydrogen. …


Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics: Task V 4th Quarterly Report, Samir Moujaes Jan 2002

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics: Task V 4th Quarterly Report, Samir Moujaes

Transmutation Sciences Materials (TRP)

The project is moving on target with the newly realigned objective set for the Phase I. Through close communications with Dr. Li and Dr. Jinsuo Zhang from LANL a realignment of the simulation work has been recommended. The reason for that is the vendor of STAR-CD/CHEMKIN had not perfected yet the final coupling of the post processing of output for any potential surface chemistry reaction taking place on the inside pipe surface of the LBE loop. This is because the coupling of CHEMKIN and STAR-CD has been done fairly recently.

Our final effort has been to generate using an innovative …


Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics, Samir Moujaes, Yitung Chen Jan 2002

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

Many of the international efforts to develop transmutation technology, including the U.S., Russian, and European scientific communities, have determined that lead bismuth eutectic (LBE) is a potential material for use as a both a spallation target and a coolant. To exploit this potential, a more thorough understanding of the effect and rates of corrosion on steels, particularly non-Russian alloys, inside the LBE systems is required. Properly controlling the oxygen content in LBE systems has been observed to drastically reduce the corrosion of structural steels in LBE. However, the transport of oxygen and formation of corrosion products is not well understood; …