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1997

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Experimental Investigation Of The Influence Of Molecular Weight On Mixing And Penetration In Supersonic Dissimilar Gaseous Injection Into A Supersonic Cross-Flow, Troy A. Giese Dec 1997

Experimental Investigation Of The Influence Of Molecular Weight On Mixing And Penetration In Supersonic Dissimilar Gaseous Injection Into A Supersonic Cross-Flow, Troy A. Giese

Theses and Dissertations

In pursuit of a more efficient and effective fuel-air mixing for a SCRAMjet combustor, this study investigated relative near field effects of molecular weight on mixing and penetration of different gaseous injection into a supersonic (M=2.9) cross flow. Helium and argon gas were chosen as injectants because of the large differences in molecular weights. Also, mixing enhancement was observed by injecting the traverse gas jet parallel to the compression face of a ramp. Color schlieren photography was used to identify the shock structures and interactions in the flow field. Measurements of mean flow properties were used to establish the jet …

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Applying Flywheel Energy Storage To Solar Electric Orbital Transfers, Mark W. Marasch Dec 1997

Applying Flywheel Energy Storage To Solar Electric Orbital Transfers, Mark W. Marasch

Theses and Dissertations

This study investigated the application of flywheel energy storage to minimum time, constant thrust orbital maneuvers using electric propulsion. The advantages of using stored energy to continue electric thruster operations while in eclipse were explored. The boundary value problems for several schemes of energy use were examined, and numerical solutions were found. Results of simulations utilizing energy storage were compared to results without energy storage. Schemes incorporating energy storage were found to have advantages in terms of propellant mass used, time spent in transit, and deliverable payload.

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Evaluation Of A Maximum A-Posteriori Slope Estimator For A Hartmann Wavefront Sensor, Troy B. Van Caster Dec 1997

Evaluation Of A Maximum A-Posteriori Slope Estimator For A Hartmann Wavefront Sensor, Troy B. Van Caster

Theses and Dissertations

Current methods for estimating the wavefront slope at the aperture of a telescope using a Hartmann wavefront sensor are based upon a centroid shift estimator. The centroid shift estimator determines the displacement, or shift, of the centroid off the optical axis using a moment calculation of the intensity distributions recorded in each subaperture. This centroid shift is proportional to the average slope of the wavefront in each subaperture. A maximum a-posteriori (MAP) slope estimator takes advantage of a-priori knowledge of the wavefront slope statistics and total irradiance falling on the subaperture detector arrays when determining the shift estimate. In order …

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The American Corporation In The Twenty-First Century: Future Forms Of Structure And Governance, Azizah Y. Al-Hibri Dec 1997

The American Corporation In The Twenty-First Century: Future Forms Of Structure And Governance, Azizah Y. Al-Hibri

Law Faculty Publications

This article focuses on corporate governance issues as they relate to the new technological developments and the issue of leapfrogging. I examine various theories about the new technologies and the changes in corporate governance that they may necessitate. I then assess and critique these theories in light of historical and other data. I suggest that our very concept of the corporation will be transformed by the Information Age. I also offer my own view as to the optimal forms of corporate governance that can equip American corporations with sufficient tools to win the accelerating competition anticipated for the next century. …

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Fundamentally Flawed: Extension Administrative Practice Part 1, Thomas F. Patterson Jr Dec 1997

Fundamentally Flawed: Extension Administrative Practice Part 1, Thomas F. Patterson Jr

Journal of Extension

The first of a two-part series addressing Extension administration, this commentary challenges traditional Extension administrative practice, arguing that current techniques are fundamentally flawed and inappropriate in the modern work place. The classical school of management is defined, and its underlying foundational assumptions are examined and ultimately rejected.

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4-H Classroom Science Programs Enriching The Learning Environment, Robert L. Horton, Joseph Konen Dec 1997

4-H Classroom Science Programs Enriching The Learning Environment, Robert L. Horton, Joseph Konen

Journal of Extension

This study addresses the role of 4-H Classroom Science Programs as a catalyst for enriching the learning environment of students. Convinced that 4-H could have an impact on the quality of science education in the classroom, researchers from The National Center for Science Teaching and Learning and the National 4-H Network for Action in Science and Technology set out to establish a model approach for the delivery of 4-H classroom science programs. The model put forth in this program shows great promise in guiding the science enrichment efforts of 4-H professionals across the country. Clearly, 4-H can play a role …

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Deafdigest: Vol. 2, No. 17 November 30, 1997, Barry Strassler Nov 1997

Deafdigest: Vol. 2, No. 17 November 30, 1997, Barry Strassler

DeafDigest 1997

No abstract provided.

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A 110,000‐Year History Of Change In Continental Biogenic Emissions And Related Atmospheric Circulation Inferred From The Greenland Ice Sheet Project Ice Core, L. David Meeker, Paul A. Mayewski, Mark S. Twickler, Sallie I. Whitlow, Debra A. Meese Nov 1997

A 110,000‐Year History Of Change In Continental Biogenic Emissions And Related Atmospheric Circulation Inferred From The Greenland Ice Sheet Project Ice Core, L. David Meeker, Paul A. Mayewski, Mark S. Twickler, Sallie I. Whitlow, Debra A. Meese

Faculty Publications

The 110,000‐year record of ammonium concentrations from the Greenland Ice Sheet Project 2 (GISP2) ice core provides the basis for an analysis of terrestrial biological production and atmospheric circulation patterns involved in the transport of biologically produced ammonium to the Greenland atmosphere. The directly measured concentration series was selected for analysis, rather than that of estimated ammonium flux, after a detailed analysis of the relationship among ice core glaciochemical concentrations and a high‐resolution simultaneous record of snow accumulation from the GISP2 core. Analysis of the ammonium concentration series shows that maxima in background levels of ammonium in the Greenland atmosphere …

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Wright State University Vs. Ohio University Basketball Program 1997-1998, Wright State University Athletics Nov 1997

Wright State University Vs. Ohio University Basketball Program 1997-1998, Wright State University Athletics

Athletics Publications

A eighty-four page program for the 1997 Wright State versus Ohio University men's basketball game. This program includes photographs, player stats, records and more.

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November 29, 1997 (Pages 6169-6314), Pennsylvania Legislative Reference Bureau Nov 1997

November 29, 1997 (Pages 6169-6314), Pennsylvania Legislative Reference Bureau

Volume 27 (1997)

No abstract provided.

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The Weekly Challenger, November 29, 1997, The Weekly Challenger, Et Al Nov 1997

The Weekly Challenger, November 29, 1997, The Weekly Challenger, Et Al

Weekly Challenger Newspaper Collection

The November 29, 1997, issue of The Weekly Challenger.

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The Murray Ledger And Times, November 29, 1997, The Murray Ledger And Times Nov 1997

The Murray Ledger And Times, November 29, 1997, The Murray Ledger And Times

The Murray Ledger & Times

No abstract provided.

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Miracle On 34th Street: The Musical, Center For Performing Arts Nov 1997

Miracle On 34th Street: The Musical, Center For Performing Arts

Center for Performing Arts Memorabilia

Playbill insert for the November 28, 1997 performance of Miracle on 34th Street.

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Preparation Of High Rate Discharge Foamed Ni-Cd Battery, Yuming Wang, Jinsheng Chen Nov 1997

Preparation Of High Rate Discharge Foamed Ni-Cd Battery, Yuming Wang, Jinsheng Chen

Journal of Electrochemistry

A novel device of SC type foamed NiCd battery is presented, in which, the innerresistance of battery is appeared to be reduced, and the electrode performance is gained to very improved, and so, this battery can be suited to using of the powerdrive pistol drill.

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Study On The Oxygen Electrodes Of Alkaline Fuel Cells Effect Of Dopant On The Activity Of Ag/C Catalyst, Jiawei Teng, Linhua Jin, Luncheng Tang Nov 1997

Study On The Oxygen Electrodes Of Alkaline Fuel Cells Effect Of Dopant On The Activity Of Ag/C Catalyst, Jiawei Teng, Linhua Jin, Luncheng Tang

Journal of Electrochemistry

A new kind of nonnoble catalyst for the oxygen electrodes of Alkaline Fuel Cells was investigated. The AgNiBiHg/C catalyst, which was prepared by chemical reduction, was active for the cathodic reduction of oxygen in alkaline fuel cells. It was found that the catalytic activity was improved by adding Ni, Bi, Hg to Ag/C catalyst, and the maximum activity was observed at Ag50%-Ni2%-Bi3%-Hg3%-C42%(wt%). XRD inconjunction with SEM indicated that the crystalline silver turned into amorphous in the presence of doping agents and the grain size of silver was reduced. No dramatic deactivation of the catalyst occured after 5200 hours of service.

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Advances In Solid Polymer Electrolytes, Liming Ding, Shaojun Dong, Erkang Wang Nov 1997

Advances In Solid Polymer Electrolytes, Liming Ding, Shaojun Dong, Erkang Wang

Journal of Electrochemistry

The formation, classification, applications and ion-transport mechanism studies of solid polymer electrolytes were reviewed. While the recent SPE reports on the preparation of novel materials, the full structure determinations of PEO/salt complexes, the exploration of ion-transport mechanism and the applications in electrochemical devices being introduced, some prospects on the future SPE research were suggested.

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Li/Α-Sn(Hpo4)2 Cell And Its Reaction Mechanism, Yuan Lin, Runliang Cai, Haoqing Wu Nov 1997

Li/Α-Sn(Hpo4)2 Cell And Its Reaction Mechanism, Yuan Lin, Runliang Cai, Haoqing Wu

Journal of Electrochemistry

The discharge mechanism of Li/α-Sn(HPO4)2 cell has been investigated by means of X-ray diffraction, XPS and cyclic voltammetry methodes. It has been shown that the electrochemical intercalation reation exists in the cathode material. There is a new phase after some degree of intercalation. With potential step and galvanostatic techniques, the chemical diffusion cofficients of Li+ in LixSn(HPO4)2 is estimated to be 10-12～10-13 cm2·s-1.

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Mechanism Of Electrodeposition Of Cu/Co Multilayer Thin Films, Jiangyun Xue, Jixun Wu, Dejun Yang Nov 1997

Mechanism Of Electrodeposition Of Cu/Co Multilayer Thin Films, Jiangyun Xue, Jixun Wu, Dejun Yang

Journal of Electrochemistry

The mechanism of electrodeposition of Cu/Co multilayer thin films has been studied by means of potentodynamic sweep, cyclic voltammetry sweep and AC impendance. The results indicated that the copper deposition is mass transfer controlled process and the cobalt deposition is related to the absorbed intermediate species such as Co(OH)ads. The cobalt ions first form Co(OH)ads, then was deoxygenated to cobalt on the electrode surface.

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Study On Perchlorate Produced By Electrolysis With Oxygen Cathode, Zhigang Shao, Baolian Yi, Naichao Li, Ming Han Nov 1997

Study On Perchlorate Produced By Electrolysis With Oxygen Cathode, Zhigang Shao, Baolian Yi, Naichao Li, Ming Han

Journal of Electrochemistry

A new method of measuring the flow capacity of cell gas in the perchlorate cell process equipped with an oxygen cathode is applided to investigate the influence of changes in the concentration of solution (chloride, chlorate, perchlorate and metal ion) and changes in the operation parameters (current density, temperature and pH) on perchlorate current efficiency. The main abstacle that the oxygen cathode is used in the perchlorate cell process is put forward and a method is provided to resolve it.

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The Effect Of Solution Composition On The Corrosion Behavior Of Electrodeposited Zinc Powder, Qingwen Li, Qin Yang, Xi Xia Nov 1997

The Effect Of Solution Composition On The Corrosion Behavior Of Electrodeposited Zinc Powder, Qingwen Li, Qin Yang, Xi Xia

Journal of Electrochemistry

Zinc powder as a widely anode material can be electrowon from ZnCl2 or ZnO+KOH media. The properties of zinc powder are likely to be modified with electrolytic conditions such as the composition of bath solution, electrolysis manner, current density and additives etc.. In this paper, we have discussed the effect of the compositions of bath solution on the microstructure and corrosion resistance of zinc powder.

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The Activity Of Alloy Cu-Ni Electrode In Electroreduction Of Aromatic Nitro-Compounds, Chunan Ma, Shaoping Tong, Xiaojun Cheng, Hui Wang Nov 1997

The Activity Of Alloy Cu-Ni Electrode In Electroreduction Of Aromatic Nitro-Compounds, Chunan Ma, Shaoping Tong, Xiaojun Cheng, Hui Wang

Journal of Electrochemistry

Cu-Ni alloy on the basis of copper at different ratio Cu/Ni are prepared by codepostion. The cathode activtiy of film are studied by steady-state polarization for electroreduction nitro-benzene (NB) and 1,5-dinitroanthraquinone (1,5-DNA) to p-aminophenol and 1,5-diamino-4,8-dihydroanthraquinone respectly. The results show that the alloy cathodes at different ratio Cu/Ni have different exchange current density (io) and apparent activition energy (EA). The alloy (CN-30) has maximal io and minimal EA by codeposition at the following conditions: electrolyte: 0.05 mol/L CuSO4·5H2O+0.6 mol/L NiSO4·6H2O+0.25 mol/L Na3Cit·2H2O; …

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Photoluminescence Of Photoelectrochemically Etched N+-Si, Guozheng Li, Chengqian Zhang, Xiumei Yang Nov 1997

Photoluminescence Of Photoelectrochemically Etched N+-Si, Guozheng Li, Chengqian Zhang, Xiumei Yang

Journal of Electrochemistry

PS layer on n+-Si with (111) orientation prepered by means of photoelectrochemically etched has photo-luminescent (PL) ability like PS layer on usual n-Si. The data of PL spectra and quenching are given.

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Volume 35, Number 15: November 28, 1997, University Of North Dakota Nov 1997

Volume 35, Number 15: November 28, 1997, University Of North Dakota

University Letter Archive

No abstract provided.

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Volume 35, Number 15: November 28, 1997, University Of North Dakota Nov 1997

Volume 35, Number 15: November 28, 1997, University Of North Dakota

University Letter Archive

No abstract provided.

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The Initial Process Of Amophous Electroless Nickel, Yi Chi, Lei Zhang, Yijan Wang, Maoyuan Ma Nov 1997

The Initial Process Of Amophous Electroless Nickel, Yi Chi, Lei Zhang, Yijan Wang, Maoyuan Ma

Journal of Electrochemistry

The initial process and mophology of electroless nickel played a domination role in adhesive strenghth of EN coating. The structure of initial deposits on certain matrixes was observed by TEM analysis. The deposition of a extremaly fine grain film depended on relative contrast between a coating and a matrix in crystal lattice parameters. When the coating and matrix had similar srystal lattice parameters. A extremely fine grain film was obtained. On the contrary, when the crystal lattice parameters were very different, a amorphous structure was observed.

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Development Of A New Type Ni-S Evolution Hydrogen Electrode For Water Electrolysis, Xiaoyou Yuan, Jinyu Wang Nov 1997

Development Of A New Type Ni-S Evolution Hydrogen Electrode For Water Electrolysis, Xiaoyou Yuan, Jinyu Wang

Journal of Electrochemistry

A new type evolution hydrogen electrode NiS(N) has been made from nickel plating electrode in NiSO4CS(NH2)2 bath by electrodeposition. It is analyzed by SEM and X-ray energy spectrum. The NiS(N) electrode is different from the NiS(O) electrode (which is used in plant at present time) in surface metallograph configuration and surfer content. The results of measurement polarization curves and water electrolysis 480 hours at 5 000 A·m-2 show that the evolution hydrogen overpotential of NiS(N) electrode is decreased at least 160 mV relative to NiS(O) electrode and the stablisum of NiS(N) electrode is better …

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Molten Carbonate Fuel Cell Materials And Technology, Naichao Li, Baolian Yi Nov 1997

Molten Carbonate Fuel Cell Materials And Technology, Naichao Li, Baolian Yi

Journal of Electrochemistry

Molten Carbonate Fuel Cell materials are reviewed, and the technology of Molten Carbonate Fuel Cell are discussed.

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The Effect Of Bismuth On Microstructure Of The Cathodic Copper Deposition Of Copper Electrorefining, Daorong Lu, Jianxing Lin Nov 1997

The Effect Of Bismuth On Microstructure Of The Cathodic Copper Deposition Of Copper Electrorefining, Daorong Lu, Jianxing Lin

Journal of Electrochemistry

The electrocrystal formation, crystal orientation and the chemical composition of the cathodic copper deposition in the presence of Bi3+ in the electrolyte of acidified CuSO4 are studies by scanning electron microscopy, X-ray diffraction, atomic absorption and EDAM. The results indicate that the Bi could′t deposit on cathode when copper electrolysed at common current density i=200 A·mol/L-2 and t=60 ℃. Bi3+ scarcely effected on the crystal orientation (220) of copper deposition. High concentration Bi3+ in the electrolyte promoted (220) growth and inhibited the other crystal orientation growth. Bi3+ effected on electrocrystal formation and the cell …

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Observation Of Scaling Violations In Scaled Momentum Distributions At Hera, J. Breitweg, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti Nov 1997

Observation Of Scaling Violations In Scaled Momentum Distributions At Hera, J. Breitweg, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

Charged particle production has been measured in deep inelastic scattering (DIS) events over a large range of x and Q2 using the ZEUS detector. The evolution of the scaled momentum, xp, with Q2, in the range 10 to 1280 GeV2, has been investigated in the current fragmentation region of the Breit frame. The results show clear evidence, in a single experiment, for scaling violations in scaled momenta as a function of Q2. © 1997 Elsevier Science B.V.

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The Ticker, November 26, 1997 Nov 1997

The Ticker, November 26, 1997

The Ticker

The Ticker is the student newspaper of Baruch College. It has been published continuously since 1932, when the Baruch College campus was the School of Business and Civic Administration of the City College of New York.

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