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Vectorial electron transfer in spatially ordered arrays. Progress report, January 1991--December 1991

Description: Progress has been made in four areas: the synthesis of new materials for directional electron; the preparation and characterization of anisotropic composites bearing organic and inorganic components; the elaboration of mechanisms of electrocatalysis; and the development of new methods for surface modification of metals and semiconductors.
Date: January 1, 1992
Creator: Fox, M. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Realtime structural electrochemistry of platinum clusters using dispersive XAFS

Description: Chemical reference tables state that the standard potential for the reaction of Pt with water, Pt + 2H{sub 2}O {r_arrow} Pt(OH){sub 2} + 2H{sup +} + 2e{sup {minus}}, is 0.98 V, and electrochemical studies propose that this reaction may occur at potentials as low as 0.8 V. Using dispersive x-ray absorption fine-structure (XAFS) spectroscopy, the authors have directly probed the structural evolution of a Pt catalyst operating in-situ in a polymer electrolyte fuel cell during cyclic voltammetry. T… more
Date: December 31, 1993
Creator: Allen, P. G.; Conradson, S. D.; Wilson, M. S.; Gottesfeld, S. & Raistrick, I. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A study of the electrochemical behavior in tungsten and caustic solutions and platinum/iridium in chloride solutions, informal report

Description: Platinum/iridium and tungsten wires were electronically etched in chloride and caustic solution, respectively, to produce tips with high aspect ratio. A direct relationship between the meniscus and the aspect ratio of etched tips was established. Scanning electron micrographs indicated that higher aspect ratios were obtained by changing the geometry of the meniscus during the etch either by an increase in the applied a.c. voltage or with the addition of a nonpolar layer above the electrolytic s… more
Date: November 22, 1994
Creator: Vitus, C. M.; Isaacs, H. S. & Schroeder, V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Reaction kinetics and product distributions in photoelectrochemical cells. Report on research activities, March 15, 1991--March 14, 1994

Description: Semiconductor/liquid junction solar cells, also called photoelectrochemical cells (PEC), represent a versatile way to use solar energy. Photon energy can be used to make electricity and chemical fuels or can be used as an alternative to thermal activation energy in photocatalytic cells. Two fundamental processes associated with photoelectrochemical solar energy conversion were investigated experimentally: (i) Reactions of `hot` electrons, and (ii) Electrode kinetics at 2-dimensional materials.
Date: September 1, 1993
Creator: Koval, C. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Dynamic structural effects and ultrafast biomolecular kinetics in photoinduced charge transfer reactions. Progress report, September 15, 1990--March 14, 1992

Description: During the first budget significant progress was made in three areas: (1) assessment of dynamic structural effects accompanying charge transfer, (2) electrochemical assessment of site-to-site electronic coupling in simple inorganic systems, and (3) direct observation of intramolecular electron transfer kinetics in mixed-valence systems. In area 1 the most significant finding was that Franck-Condon parameters for electron transfer (i.e. normal coordinate displacements, vibrational frequencies, a… more
Date: January 1, 1992
Creator: Hupp, J. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Characterization of electrochemically modified polycrystalline platinum surfaces

Description: The characterization of electrochemically modified polycrystalline platinum surfaces has been accomplished through the use of four major electrochemical techniques. These were chronoamperometry, chronopotentiommetry, cyclic voltammetry, and linear sweep voltammetry. A systematic study on the under-potential deposition of several transition metals has been performed. The most interesting of these were: Ag, Cu, Cd, and Pb. It was determined, by subjecting the platinum electrode surface to a singl… more
Date: December 1, 1991
Creator: Krebs, L. C. & Ishida, Takanobu
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Engineering scaleup of electrical soil heating for soil decontamination

Description: The objective of PNL`s efforts in electrically based methods for environmental restoration is to provide new and cost-effective means for removing hazardous organic contaminants from soils, and to detoxify those contaminants after they are removed. Recent work has concentrated on two areas: electrical soil heating to remove volatile and semivolatile compounds from soils, and in situ oxidation via a form of low-temperature plasma to decompose nonvolatile and bound contaminants. This paper covers… more
Date: August 1, 1992
Creator: Heath, W. O.; Roberts, J. S.; Lessor, D. E. & Bergsman, T. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Simulations of metal dissolution and corrosion. Final report, January 1993-June 1994

Description: There has been considerable interest in microscopic aspects of material removal processes in fields such as corrosion, erosion, evaporation, battery technology, electropolishing, and semiconductor etching. Reports of theoretical work related to many of these problems can be found in the literature although metal dissolution is a noticeable exception. Critical issues common to all dissolution reactions include the relationship between the surface morphology and the driving term (e.g. potential, … more
Date: March 1, 1995
Creator: Searson, P. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Semiconductor electrochemistry of coal pyrite. Quarterly technical progress report, July--September 1993

Description: Pyrite (FeS{sub 2}) synthesis was studied in aqueous solution at room temperature and pressure using ferric chloride (FeCl{sub 3}) and sodium hydrosulfide (NaHS) as reactants, and sodium hexametaphosphate ((NaPO{sub 3}){sub 6}) as dispersant, which was added in the system to control the particle size of pyrite. The effects of the reaction pH and the concentrations of the reactants and the dispersant on the characterization of pyrite were studied. The pH of the reaction determines the products o… more
Date: December 31, 1993
Creator: Osseo-Asare, K. & Wei, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The effect of gamma radiation on reference electrodes and platinum and carbon steel bare metal electrodes in a simulated waste solution

Description: Electrochemical potential measurements of materials in waste tanks are important in determining if the materials have a propensity for stress corrosion cracking and pitting. Potential measurement requires a reference electrode, but the effect of radiation on the potential generated by the reference electrode has been an unknown quantity. To determine the significance of the radiation effect, Pacific Northwest Laboratory conducted studies of five types of electrodes under gamma radiation at room… more
Date: March 1, 1994
Creator: Danielson, M. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Reference electrodes for solid polymer electrolytes

Description: Electrochemical experiments were conducted on a binary metallic lithium-tin alloy that may be suitable as a reference electrode of the first kind in studies of lithium-polymer batteries. Two types of tin electrodes were tested: bulk tin foil and tin thin films deposited on a stainless steel substrate. Electrochemical test cells were fabricated, with tin, metallic lithium, poly(ethylene oxide), and lithium trifluoromethanesulfonate as electrodes and polymer electrolyte material. To form the allo… more
Date: December 31, 1993
Creator: Johnson, C. S. & Dees, D. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Anodic oxidation of tetrasodium ethylenediaminetetraacetic acid in alkaine solutions

Description: Electrochemical oxidation is being increasingly considered in recent years as a technique to destroy organic compounds in industrial waste. Johnson studied the anodic oxidation of HEDTA on platinum in acid sulfate solutions. Polarizations relationships were obtained and numerous reactions products were identified that indicated a sequential removal of acetate groups from the EDTA. The initial decarboxylation was followed by a reverse Schiff-type reaction which produced formaldehyde and the corr… more
Date: February 1, 1995
Creator: Pakalapati, S. N. R.; Popov, B. N.; White, R. E. & Hobbs, D. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Semiconductor electrochemistry of coal pyrite. Technical progress report, July--September 1993

Description: Pyrite (FeS{sub 2}) synthesis was studied in aqueous solution at room temperature and atmospheric pressure using ferric chloride (FeCl{sub 3}) and sodium hydrosulfide (NaHS) as reactants, and sodium hexametaphosphate ((NaPO{sub 3}){sub 6}) as dispersant and crystal growth modifier (to control the particle size of pyrite). The effects of the reaction pH and the concentrations of the reactants and the dispersant on the product characteristics were studied. The pH of the reaction system determines… more
Date: November 1, 1993
Creator: Osseo-Asare, K. & Wei, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

[Photoinduced charge separation in solid-state and molecular systems: Year three progress report]

Description: Our goal is to understand the role of intrinsic cyanometalate overlayers in modulating interfacial photoinduced charge transfer processes occurring at the cadmium chalconide/aqueous ferri-ferrocyanide interface. To accomplish this goal, detailed structural and charge transfer studies of [CdFe(CN){sub 6}]{sup 2-/1-} overlayers generated either intrinsically via photoelectrochemistry at the illuminated CdX/[Fe(CN){sub 6}]{sup 4-/32} (X=S or Se) interface, or synthesized as chemical modification l… more
Date: December 31, 1991
Creator: Bocarsly, A. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Control of high level radioactive waste-glass melters. Part 6, Noble metal catalyzed formic acid decomposition, and formic acid/denitration

Description: A necessary step in Defense Waste Processing Facility (DWPF) melter feed preparation for the immobilization of High Level Radioactive Waste (HLW) is reduction of Hg(II) to Hg(0), permitting steam stripping of the Hg. Denitrition and associated NOx evolution is a secondary effect of the use of formic acid as the mercury-reducing agent. Under certain conditions the presence of transition or noble metals can result in significant formic acid decomposition, with associated CO{sub 2} and H{sub 2} ev… more
Date: December 31, 1990
Creator: Bickford, D. F.; Coleman, C. J.; Hsu, C. L. W. & Eibling, R. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Electrocatalysts for Oxygen Electrodes. Final Report

Description: The objectives of the research were: to develop further understanding of the factors controlling O{sub 2} reduction and generation on various electrocatalysts, including transition metal macrocycles and oxides: to use this understanding to identify and develop much higher activity catalysts, both monofunction and bifunction; and to establish how catalytic activity for a given O{sub 2} electrocatalyst depends on catalyst-support interactions and to identify stable catalyst supports for bifunctio… more
Date: October 1, 1991
Creator: Yeager, E. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Testing of CFC replacement fluids for arc-induced toxic by-products

Description: The authors have developed a unique test-stand for quantifying the generation of perfluoroisobutylene (PFIB) in chlorofluorocarbon (CFC) replacement fluids when they are subjected to high electrical stress/breakdown environments. PFIB is an extremely toxic gas with a threshold limit value of 10 ppbv as set by the American Conference of Governmental Industrial Hygienists. They have tested several new fluids from various manufacturers for their potential to generate PFIB. Their goal is to determi… more
Date: June 1, 1993
Creator: Cravey, W. R.; Goerz, D. A. & Hawley-Fedder, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pyrochemical treatment of Idaho Chemical Processing Plant high-level waste calcine

Description: The Idaho Chemical Processing Plant (ICPP), located at the Idaho National Engineering Laboratory (INEL), has reprocessed irradiated nuclear fuels for the US Department of Energy (DOE) since 1951 to recover uranium, krypton-85, and isolated fission products for interim treatment and immobilization. The acidic radioactive high-level liquid waste (HLLW) is routinely stored in stainless steel tanks and then, since 1963, calcined to form a dry granular solid. The resulting high-level waste (HLW) cal… more
Date: June 1, 1993
Creator: Todd, T. A.; DelDebbio, J. A.; Nelson, L. O. & Sharpsten, M. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Surface electrochemical control for fine coal and pyrite separation. Technical progress report, January 1, 1990--March 31, 1990

Description: Ongoing work includes the characterization of coal pyrites, the floatability evaluation of typical US coal samples, the flotation behavior of coal pyrites, the electrochemical measurement of the surface properties of coal pyrites, and the characterization of species produced at pyrite surfaces.
Date: December 31, 1990
Creator: Chen, Wanxiong; Hu, Weibai; Wann, Jyi-Perng; Zhu, Ximeng; Bodily, David M. & Wadsworth, Milton E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Surface electrochemical control for fine coal and pyrite separation. Technical progress report, April 1, 1990--June 30, 1990

Description: Ongoing work includes the characterization of coal pyrites, the floatability evaluation typical US coal samples, the flotation behavior of coal pyrites, the electrochemical measurement of the surface properties of coal pyrites, and the characterization of species produced at pyrite surfaces.
Date: December 31, 1990
Creator: Hu, Weibai; Zhu, Ximeng; Bodily, D. M. & Wadsworth, M. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Semiconductor electrochemistry of coal pyrite. Technical progress report, October--December 1993

Description: The effects of the semiconductor properties of pyrite on its electrochemical behavior have been explored with the aid of energy level diagram which illustrate the relationship between the energy levels of the solid land the equilibrium potentials of the redox couples in the aqueous solution. A novel approach to the study of pyrite electrochemistry was initiated. This approach is based on pyrite microelectrodes synthesized via aqueous phase precipitation. Preliminary results show that photocurre… more
Date: March 1, 1994
Creator: Osseo-Asare, K. & Wei, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Energy Conversion and Storage Program. 1990 annual report

Description: The Energy Conversion and Storage Program applies chemistry and materials science principles to solve problems in (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes, and (5) application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetic… more
Date: March 1, 1992
Creator: Cairns, E. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Energy Conversion and Storage Program: 1992 Annual report

Description: This report is the 1992 annual progress report for the Energy Conversion and Storage Program, a part of the Energy and Environment Division of the Lawrence Berkeley Laboratory. Work described falls into three broad areas: electrochemistry; chemical applications; and materials applications. The Energy Conversion and Storage Program applies principles of chemistry and materials science to solve problems in several areas: (1) production of new synthetic fuels, (2) development of high-performance r… more
Date: June 1, 1993
Creator: Cairns, E. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Surface electrochemical control for the fine coal and pyrite separation. Technical progress report, July 21, 1989--September 30, 1989

Description: Ongoing work includes the characterization of coal pyrites, the floatability evaluation of typical US coal samples, the flotation behavior of coal pyrites, the electrochemical measurement of the surface properties of coal pyrites, and the characterization of species produced at pyrite surfaces.
Date: December 31, 1989
Creator: Chen, Wanxiong; Hu, Weibai; Wann, Jyi-Perng; Zhu, Ximeng & Wadsworth, Milton E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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