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1999

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Studies On Methods Of Fuel Cells Electrodes Preparation, Jun Gu, Sheng Sui, Guang-Qiang Li, Zhitong Sui Nov 1999

Studies On Methods Of Fuel Cells Electrodes Preparation, Jun Gu, Sheng Sui, Guang-Qiang Li, Zhitong Sui

Journal of Electrochemistry

In fuel cells, the structure of electrodes is an important factor which effect the cell performance. To improve the structure and the performance of electrodes, a new method of providing fuel cell electrodes is proposed in this paper. PTFE (polytetrafluoroethylene) and ethyne black was ground for about half an hour in a high-speed grinder, then the catalyst was added into the grinder and milled for an hour. This milled catalyst was transferred into a mixer followed by the addition of surface-active agent. After a suspension was formed, it was filtered under vacuum condition.Then a thin uniform filter-cake of the catalyst …

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Aes Multi-Layer Structural Analysis Of Si Based Anodic Porous Alumina Films And Studies On Its Formation Mechanism, Jun-Hui Wu, Jian-Ping Zou, Qing Zhu, Xi-Mao Bao Nov 1999

Aes Multi-Layer Structural Analysis Of Si Based Anodic Porous Alumina Films And Studies On Its Formation Mechanism, Jun-Hui Wu, Jian-Ping Zou, Qing Zhu, Xi-Mao Bao

Journal of Electrochemistry

400 nm aluminum films were deposited onto a p-type, 0.5 Ω·cm,〈100〉oriented silicon wafers using electron beam evaporation technique. Then, the wafers was immersed in 15 wt% H2SO4 for porous-type over-anodization under a constant voltage of DC 60V. During the anodization,the temperature of the electrolyte was maintained at 0 ℃. The obtained samples were investigated by means of transmission electron microscopy, scanning electron microscopy, and AES depth profile for multi-layer structural information. In addition, the basic anodic formation mechanism of the Si-based aluminum films was brielfly discussed.

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Study On Electrochemical Reduction Properties Of Nitrobenzene, Chu-Na Ma, Wen-Kui Zhang, Hui Huang, Yong-Ping Gan Nov 1999

Study On Electrochemical Reduction Properties Of Nitrobenzene, Chu-Na Ma, Wen-Kui Zhang, Hui Huang, Yong-Ping Gan

Journal of Electrochemistry

The electrochemical reduction characteristics of nitrobenzene was extensively investigated by using the techniques such as quasi-steady-state polarization, cyclic voltammetry, fast linear potential sweep method and chronoamperometry in this paper. The electroanalytic properties of Cu, Cu-Hg and Cu-Ni electrodes were evaluated. Based on the study of the transient steping behaviour of nitrobenzene to PAP, the reduction mechanism was discussed. The results showed that the transition steps existed on the electrochemical reduction of nitrobenzene in acidic solution, the reactant is also absorbed on electrodes surface. The control step in the reduction of nitrobenzene was ascribed to the diffusion of nitrobenzene and its …

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A Novel Reaction Region Moving Electrode System For Electrochemical Power Sources, Jin-Kua You, Que Tu, Zheng-Jian Wang, Jie Sun, Zu-Geng Lin Nov 1999

A Novel Reaction Region Moving Electrode System For Electrochemical Power Sources, Jin-Kua You, Que Tu, Zheng-Jian Wang, Jie Sun, Zu-Geng Lin

Journal of Electrochemistry

In most of practical rechargeable batteries, charging/discharging process is always concerned with phase-transformation in the solid state. Due to the irreversibility of the phase-transformation, the cyclic performance of the rechargeable batteries are limited. In this paper, a novel reaction-region moving counter electrode system is constructed in our laboratory. The electrode system is operated at room temperature and cycled in solid-liquid phase during charging/discharging processes. With this electrode, the metal-complexes are firstly deposited (i.e. charging process) on the nearest working electrode and gradually extended to those another working electrodes several centimeters away from the counter electrode. The deposite is dissolved again …

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High Performance Proton Exchange Membrane Fuel Cells, Jing-Rong Yu, Bao-Lian Yi, Ming Han, Xiao-Liang Cheng, Zhi-Gang Shao, Jing-Xin Zhang Nov 1999

High Performance Proton Exchange Membrane Fuel Cells, Jing-Rong Yu, Bao-Lian Yi, Ming Han, Xiao-Liang Cheng, Zhi-Gang Shao, Jing-Xin Zhang

Journal of Electrochemistry

Proton-exchange membrane fuel cells(PEMFC) using a perfluorosulfonic acid proton exchange membrane as an electrolyte can simplify water and electrolyte management. In this paper, the effects of thickness of PEM on the performance of PEMFC were studied. The Nafion-112 PEM and low platinum loading E-TEK electrode yielded very high power density, of the order of 0.95 W/cm2. The energy-conversion efficiency, the degree of platinum utilization and stability for PEMFC using Nafion 112 and E-TEK electrode were also investigated.

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Photoelectrochemical Studies On The Tio2 Nanostructured Porous Film Sensitized By Cyanine Dye, Li Zhang, Mai-Zhi Yang, Xue-Bin Qiao, Yan-Zhong Hao, En-Qing Gao, Sheng-Min Cai Nov 1999

Photoelectrochemical Studies On The Tio2 Nanostructured Porous Film Sensitized By Cyanine Dye, Li Zhang, Mai-Zhi Yang, Xue-Bin Qiao, Yan-Zhong Hao, En-Qing Gao, Sheng-Min Cai

Journal of Electrochemistry

The photoelectrochemical behaviors of the TiO2 nanostructured porous film sensitized by cyanine dye were investigated in this paper. The results showed that the excitaed state level matched the conduction band edge of TiO2 nanoparticle. Therefore the sensitization of the dye can increase the photocurrent intensity of the TiO2 nanostructured electrode obviously and results in a red-shift of optical absorption from the ultra-violet region to the visible. As a result, the light-to-electricity conversion efficiency was improved evidently, the maximum value of IPCE has reached 12.1%.

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Characterization And Electrochemical Behaviour Of Ce(Ⅲ) Amino Acid Imidazole Ternary Complexes, Hui-Xia Wu, Ze-Min Wang, Hai-Feng Yang, Zong-Rang Zhang Nov 1999

Characterization And Electrochemical Behaviour Of Ce(Ⅲ) Amino Acid Imidazole Ternary Complexes, Hui-Xia Wu, Ze-Min Wang, Hai-Feng Yang, Zong-Rang Zhang

Journal of Electrochemistry

Two Ce(Ⅲ)-amino acid-imidazole teranry complexe were synthesized,These complexes have the composition of Ce(Trp)3IM(NO3)3·3H2O and Ce(Phe)3IM(NO3)3 respectively. The IR spectra indicate that the carboxy group of amino-acid and the N atoms of imidazole are coordinated with Ce(Ⅲ) ion. Cyclic voltammetry was used to study the electrochemical behaviour of Ce(Ⅲ) ion, the mixture of Ce(Ⅲ) with ligands, and Ce(Ⅲ) binary or ternary complexes. Within the scan range of -0.1 to 1.10 V (vs.SCE), both of ternary complexes depicted completely irreversible electron transfer process.

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Investigation Of Sodium Hypophosphite Anodic Oxidizing Behavior In The Process Of Acid Electroless Nickel Deposition, Mei-Yuan Wang, Ya-Fei Kuang, Yan Xu Nov 1999

Investigation Of Sodium Hypophosphite Anodic Oxidizing Behavior In The Process Of Acid Electroless Nickel Deposition, Mei-Yuan Wang, Ya-Fei Kuang, Yan Xu

Journal of Electrochemistry

The anodic oxidizing behavior of sodium hypophosphite in the process of electroless nickle deposition (pH=5.5) was investigated with the linear potential sweep method and alternating current impedance. The results indicated that, the oxidation of NaH2PO2 was a complicated electrochemical process and affected by the concentration of NaH2PO2, the temperature of the bath, the sweep rate and the existence of nickel ion. The NaH2PO2 electrooxidation reaction was very likely preceded by heterogeneous interface transformation process, which might be the control step of the whole anodic process.

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The Preparation Of Flexible Polymeric Anode And The Measurement Of Its Protective Ability For Cathodic Protection, Ai-Ling Du, He-Ming Zhang, Ming-Zong Zhang, Shi-De Ma Nov 1999

The Preparation Of Flexible Polymeric Anode And The Measurement Of Its Protective Ability For Cathodic Protection, Ai-Ling Du, He-Ming Zhang, Ming-Zong Zhang, Shi-De Ma

Journal of Electrochemistry

The flexible electrode, whose shape can be changed freely, was made of ethenyl copolymer and conductive component and proper amount of additive for cathodic protection. The resistance of electrode was measured.In low concentration of H2SO4, the flexible electrode can be used as auxiliary anode to protect the carbon steel. The protection ability of the flexible auxiliary anode was measured too.

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Studies Of The Electrode Preparation Of Electrode From Lead Carbonate For Lead Acid Batteryⅰ. The Activation Of The Pme, Zhong-Xu Dai, Di-Hua Wang, Jun-Wei Jiang, Yun-Hong Zhou, Jin-Yun Zou Nov 1999

Studies Of The Electrode Preparation Of Electrode From Lead Carbonate For Lead Acid Batteryⅰ. The Activation Of The Pme, Zhong-Xu Dai, Di-Hua Wang, Jun-Wei Jiang, Yun-Hong Zhou, Jin-Yun Zou

Journal of Electrochemistry

Lead carbonate which was an intermediate product in lead hydrometallurgy without pollution of lead vapor and sulfur dioxide was selected as electrode material of lead-acid batteries. In the present work, the performances of PbO2/PbSO4 or PbSO4/Pb electrode transformed from PbCO3 have been investigated by powder microelectrode technique combined with cyclic voltammetry. The results show that the CV characteristics of either negative or positive electrode prepared from PbCO3 is as good as that of both electrodes made from lead oxide produced by mill machine,when a powder microelectrode with PbCO3 transformed into PbSO 4 …

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Net Ecosystem Productivity And Its Uncertainty In A Diverse Boreal Peatland, Jill L. Bubier, Steve Frolking, P Crill, Ernst Linder Nov 1999

Net Ecosystem Productivity And Its Uncertainty In A Diverse Boreal Peatland, Jill L. Bubier, Steve Frolking, P Crill, Ernst Linder

Earth Sciences

Net ecosystem exchange (NEE) of CO2 was measured in four peatlands along plant community, hydrologic, and water chemistry gradients from bog to rich fen in a diverse peatland complex near Thompson, Manitoba, as part of the Boreal Ecosystem-Atmosphere Study (BOREAS). A simple model for estimating growing season net ecosystem productivity (NEP) using continuous measurements of photosynthetically active radiation (PAR), and peat temperature was constructed with weekly chamber measurements of NEE from May to October 1996. The model explained 79–83% of the variation in NEE across the four sites. Model estimation and parameter uncertainty calculations were performed using nonlinear regression …

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Recent Laboratory Tests Of A Hard X-Ray Solar Flare Polarimeter, Mark L. Mcconnell, John R. Macri, M Mcclish, Jack Ryalls Nov 1999

Recent Laboratory Tests Of A Hard X-Ray Solar Flare Polarimeter, Mark L. Mcconnell, John R. Macri, M Mcclish, Jack Ryalls

Space Science Center

We report on the development of a Compton scatter polarimeter for measuring the linear polarization of hard X-rays (50 - 300 keV) from solar flares. Such measurements would be useful for studying the directivity (or beaming) of the electrons that are accelerated in solar flares. We initially used a simple prototype polarimeter to successfully demonstrate the reliability of our Monte Carlo simulation code and to demonstrate our ability to generate a polarized photon source in the lab. We have recently fabricated a science model based on a modular design concept that places a self-contained polarimeter module on the front-end of …

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Changes Of Wage Differentials By Occupations And Educational Qualifications In Hong Kong : Analysis And Implications For Public Policy, Wai Chung, Gary Wong Nov 1999

Changes Of Wage Differentials By Occupations And Educational Qualifications In Hong Kong : Analysis And Implications For Public Policy, Wai Chung, Gary Wong

Lingnan Theses (MPhil & PhD)

The dramatic increase in the wage differentials between skilled and unskilled workers observed in many developed countries have received much attention from economists. In Hong Kong, however, few empirical studies have been carried out to explain the growing wage gap. This study uses both published and unpublished data to investigate the trend of wage gaps between occupational classifications and educational qualifications, and to test a variety of hypotheses about the sources of rising wage gaps. The results show that the wage differential by skill levels decreased in the first half of the 1980s, began to increase in the late 1980s, …

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A Construction Of Orthogonal Compactly-Supported Multiwavelets On $\R^{2}$, Bruce Kessler Nov 1999

A Construction Of Orthogonal Compactly-Supported Multiwavelets On $\R^{2}$, Bruce Kessler

Mathematics Faculty Publications

This paper will provide the general construction of the continuous, orthogonal, compactly-supported multiwavelets associated with a class of continuous, orthogonal, compactly-supported scaling functions that contain piecewise linears on a uniform triangulation of $\R^2$. This class of scaling functions is a generalization of a set of scaling functions first constructed by Donovan, Geronimo, and Hardin. A specific set of scaling functions and associated multiwavelets with symmetry properties will be constructed.

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November 24, 1999 Cal Poly Report, Public Affairs Office Nov 1999

November 24, 1999 Cal Poly Report, Public Affairs Office

Cal Poly Report

No abstract provided.

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On The Green Vol. 30 No. 5 November 24, 1999, Gallaudet University Nov 1999

On The Green Vol. 30 No. 5 November 24, 1999, Gallaudet University

1991-2000

On the Green is an internal publication of Gallaudet College, which later became Gallaudet University. It notified employees of updates around the campus and in the broader community, including new construction and the establishment of new academic programs. Running until 2010, it was supplanted by various forms of online mass communications across multiple audiences.

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Catalyst, New College Of Florida Nov 1999

Catalyst, New College Of Florida

Student Publications

Eight page issue of the student produced newspaper.

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November 24th 1999, Hispanic News Nov 1999

November 24th 1999, Hispanic News

Inland Empire Hispanic News

No abstract provided.

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Interacting Topological Defects On Frozen Topographies, Mark Bowick, David R. Nelson, Alex Travesset Nov 1999

Interacting Topological Defects On Frozen Topographies, Mark Bowick, David R. Nelson, Alex Travesset

Physics - All Scholarship

We propose and analyze an effective free energy describing the physics of disclination defects in particle arrays constrained to move on an arbitrary two-dimensional surface. At finite temperature the physics of interacting disclinations is mapped to a Laplacian Sine-Gordon Hamiltonian suitable for numerical simulations. We then specialize to the case of a spherical crystal at zero temperature. The ground state is analyzed as a function of the ratio of the defect core energy to the Young's modulus. We argue that the core energy contribution becomes less and less important in the limit R >> a, where R is the radius of …

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Motions 1999 Volume 35 Number 3, University Of San Diego School Of Law Student Bar Association Nov 1999

Motions 1999 Volume 35 Number 3, University Of San Diego School Of Law Student Bar Association

Newspaper, Motions (1987-2019)

No abstract provided.

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Remote Sensing Of Photosynthetic-Light-Use Efficiency Of Boreal Forest, Caroline J. Nichol, Karl F. Huemmrich, T. Andrew Black, Paul G. Jarvis, Charles L. Walthall, John Grace, Forrest G. Hall Nov 1999

Remote Sensing Of Photosynthetic-Light-Use Efficiency Of Boreal Forest, Caroline J. Nichol, Karl F. Huemmrich, T. Andrew Black, Paul G. Jarvis, Charles L. Walthall, John Grace, Forrest G. Hall

United States National Aeronautics and Space Administration: Publications

Using a helicopter-mounted portable spectroradiometer and continuous eddy covariance data we were able to evaluate the photochemical reflectance index (PRI) as an indicator of canopy photosynthetic light-use efficiency (LUE) in four boreal forest species during the Boreal Ecosystem Atmosphere experiment (BOREAS). PRI was calculated from narrow waveband reflectance data and correlated with LUE calculated from eddy covariance data. Significant linear correlations were found between PRI and LUE when the four species were grouped together and when divided into functional type: coniferous and deciduous. Data from the helicopter-mounted spectroradiometer were then averaged to represent data generated by the Airborne Visible Infrared …

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Dual Function Euv Multilayer Mirrors For The Image Mission, David D. Allred, R. Steven Turley, Matthew B. Squires Nov 1999

Dual Function Euv Multilayer Mirrors For The Image Mission, David D. Allred, R. Steven Turley, Matthew B. Squires

Faculty Publications

We have developed a new family of EUV multilayer mirror coatings using uranium. Using this approach we have coated a set of six mirrors for the EUV Imager, a component of the IMAGE mission. This mission is a Medium Explorer (MIDEX) program, which is scheduled for launch early in 2000. The EUV Imager will study the distribution of He+ in the Earth's plasmasphere by detecting its resonantly scattered emission at 30.4 nm (41 eV) and will produce images of the structure and dynamics of the cold plasma on a global scale. There is, however, a bright at 58.4 nm (21 …

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Faculty Senate Meeting Minutes, 11/23/1999, P 82-105, Unm Faculty Senate Nov 1999

Faculty Senate Meeting Minutes, 11/23/1999, P 82-105, Unm Faculty Senate

Faculty Senate Meeting Minutes, 1920 - 2013

No abstract provided.

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Mustang Daily, November 22, 1999 Nov 1999

Mustang Daily, November 22, 1999

Cal Poly Student Newspaper

Student newspaper of California Polytechnic State University, San Luis Obispo, CA.

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November 22, 1999, James Madison University Nov 1999

November 22, 1999, James Madison University

The Breeze, 1990-1999

The Breeze is the student newspaper of James Madison University in Harrisonburg, Virginia.

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On Campus, November 22, 1999, Coastal Carolina University Nov 1999

On Campus, November 22, 1999, Coastal Carolina University

On Campus Newsletter

A Newsletter for Faculty and Staff of Coastal Carolina University. Volume 9, Number 19

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Univercity News (1999-11-22) Nov 1999

Univercity News (1999-11-22)

UniverCity News, 1998-2001

VCU Today, the University’s first official administrative organ, began as a somewhat irregular monthly publication but moved to a bi-weekly newspaper format in the 1980s. The newspaper changed its name to VCU Voice in 1988 and ten years later it appeared under the title UniverCity News. As it neared the end of its run as a physical newspaper, the publication became simply VCU News. These four publications were essentially the same periodical published under different titles by the Office of University Relations. VCU News appeared online for the first time in 2002.

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Faculty Newsnotes 1999 No. 323, Office Of The Provost Nov 1999

Faculty Newsnotes 1999 No. 323, Office Of The Provost

Faculty Newsnotes (1972-2010)

No abstract provided.

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On Measuring The Cost Of Children:The Case Of Rural Maharashtra., Manisha Chakrabarty Dr. Nov 1999

On Measuring The Cost Of Children:The Case Of Rural Maharashtra., Manisha Chakrabarty Dr.

Doctoral Theses

In this dissertation we have attempted to measure the cost of children, which plays a crucial role in matters relating to welfare and public policy like child benefits and compensation policies of the government. The cost is measured based on the single equation as well as the systems approach using the 38th round National Sample Survey (NSS) data on household consumer expenditure for rural Maharashtra (relating to the period of January to December, 1983).The first chapter provides a brief account of the basic literature on empirical demand analysis which is relevant for welfare comparison between households. To be specific in …

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Selective Excitation And Thermal Quenching Of The Yellow Luminescence Of Gan, John S. Colton, P. Y. Yu, K. L. Teo, E. R. Weber, P. Perlin, I. Grzegory, K. Uchida Nov 1999

Selective Excitation And Thermal Quenching Of The Yellow Luminescence Of Gan, John S. Colton, P. Y. Yu, K. L. Teo, E. R. Weber, P. Perlin, I. Grzegory, K. Uchida

Faculty Publications

We report the observation of narrower structures in the yellow luminescence of bulk and thin-film n-type GaN, using the technique of selective excitation. These fine structures exhibit thermal quenching associated with an activated behavior. We attribute these fine structures to phonons and electronic excitations of a shallow donor-deep acceptor complex, and determine its activation energy for delocalization. Our results suggest that in addition to distant donor-acceptor pairs, the yellow luminescence can also involve emission complexes of shallow donors and deep acceptors.

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