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2004 DOE Hydrogen, Fuel Cells & Infrastructure Technologies Program Review Presentation COST AND PERFORMANCE ENHANCEMENTS FOR A PEM FUEL CELL TURBOCOMPRESSOR

Description: The objective is to assist the Department of Energy in the development of a low cost, reliable and high performance air compressor/expander. Technical Objective 1: Perform a turbocompressor systems PEM fuel cell trade study to determine the enhanced turbocompressor approach. Technical Objective 2: Using the results from technical objective 1, an enhanced turbocompressor will be fabricated. The design may be modified to match the flow requirements of a selected fuel cell system developer. Technical Objective 3: Design a cost and performance enhanced compact motor and motor controller. Technical Objective 4: Turbocompressor/motor controller development.
Date: April 1, 2004
Creator: Gee, Mark K.

Development of chromium-tungsten alloys

Description: Cr alloys containing 0-30 weight % W were investigated for their high temperature strength and oxidation resistance. These experimental alloys are intended for use in elevated temperature applications. Alloys were melted in a water-cooled, copper-hearth arc furnace. Microstructure of the alloys was studied using X-ray diffraction, scanning electron microscopy, and light microscopy. Meyer and Vickers hardness tests were utilized for measuring room temperature strength. A hot hardness tester with a spherical ruby indenter was used to study the strength of these materials between 800ºC and 1200ºC. A parabolic relationship was observed between load and indent size at all temperatures. On the other hand, decrease in hardness of the alloys with temperature was linear up to 1200ºC.
Date: March 1, 2004
Creator: Dogan, Omer N.; Alman, David E. & Hawk, Jeffrey A.

Factors Controlling In Situ Uranium and Technetium Bioreductionat the NABIR Field Research Center

Description: This research hypotheses is: (1) Indigenous microorganisms in the shallow aquifer at the FRC have the capability to reduce U(VI) and Tc(VII) but rates are limited by--Scarce electron donor, Low pH and potentially toxic metals, and High nitrate. (2) U(VI) and Tc(VII) reduction rates can be increased by--Successive donor additions, Raising pH to precipitate toxic metals, and Adding humics to complex toxic metals and serve as electron shuttles.
Date: March 17, 2004
Creator: Istok, J.; Jones, J.; Park, M.; Sapp, M.; Selko, E.; Laughman, R. et al.

Geobacter Project

Description: Analysis of the Genetic Potential and Gene Expression of Microbial Communities Involved in the In Situ Bioremediation of Uranium and Harvesting Electrical Energy from Organic Matter The primary goal of this research is to develop conceptual and computational models that can describe the functioning of complex microbial communities involved in microbial processes of interest to the Department of Energy. Microbial Communities to be Investigated: (1) Microbial community associated with the in situ bioremediation of uranium-contaminated groundwater; and (2) Microbial community that is capable of harvesting energy from waste organic matter in the form of electricity.
Date: March 17, 2004
Creator: Lovley, Derek; Coppi, Maddalena; Ciufo, Stacy; Methe, Barbara; Pablo, Pomposiello; Sandler, Steve et al.

Influence of Reactive Transport on the Reduction of U(VI) in the Presence of Fe(III) and Nitrate: Implications for U(VI) Immobilization by Bioremidation/Biobarriers

Description: The purposes of this report are to: (1) to determine how flow and transport influence the distribution of U(VI) under field-relevant conditions and the transfer of reductive equivalents to the aqueous and solid phases by DMRB; and (2) to examine the solid-phase stability of bioreduced uranium phases--effects of mass transfer on reoxidation of U(IV) by O{sub 2} and other oxidants (e.g., NO{sub 3}{sup -}, denitrification products).
Date: March 17, 2004
Creator: Wood, Brian; Liu, Chongxuan & Zachara, John

NABIR Field Research Center Oak Ridge, Tennessee

Description: The objective of this report is to understand fundamental biogeochemical processes that would allow for the use of bioremediation approaches for cleaning up, managing, or understanding fate and transport at DOE's contaminated legacy waste sites.
Date: March 17, 2004
Creator: Watson, David

New Insights into the Mechanism of Bacterial Metal Respiration

Description: This project goal is to identify genes and gene products required for microbial metal reduction: reductive dissolution of iron; reductive dissolution of manganese; reductive precipitation of selenium; reductive precipitation of uranium; and reductive precipitation of technetium.
Date: April 17, 2004
Creator: DiChristina, Thomas J.

PNNL/Alabama/ORNL Project Activities and Results

Description: The hypothesis of this report is Mobile radionuclides in low-permeability porous matrix regions of fractured saprolite can be effectively isolated and immobilized by stimulating localized in-situ biological activity in highly-permeable fractured and microfractured zones within the saprolite.
Date: March 17, 2004
Creator: Scheibe, Timothy D.; Roden, Eric E.; Brooks, Scott C. & Zachara, John M.

Reaction-Based Reactive Transport Modeling of Biological Iron(III) Reduction

Description: The summary of this report is: (1) biogenic flux increases as hydrologic residence time decreases; (2) reaction-based reactive transport modeling can capture this effect; (3) solid-phase Fe(III) bioreduction can be sustained at long residence times in natural sediments; and (4) long-term coupled Fe(III)/U(VI) bioreduction can be sustained in natural sediments.
Date: March 17, 2004
Creator: Burgos, Bill

Reduction of U(VI) Complexes by Anthraquinone Disulfonate: Experiment and Molecular Modeling

Description: Past studies demonstrate that complexation will limit abiotic and biotic U(VI) reduction rates and the overall extent of reduction. However, the underlying basis for this behavior is not understood and presently unpredictable across species and ligand structure. The central tenets of these investigations are: (1) reduction of U(VI) follows the electron-transfer (ET) mechanism developed by Marcus; (2) the ET rate is the rate-limiting step in U(VI) reduction and is the step that is most affected by complexation; and (3) Marcus theory can be used to unify the apparently disparate U(VI) reduction rate data and as a computational tool to construct a predictive relationship.
Date: March 17, 2004
Creator: Ainsworth, C.C.; Wang, Z.; Rosso, K.M.; Wagnon, K. & Fredrickson, J.K.

Test Readiness Diagnostics

Description: No abstract prepared.
Date: April 30, 2004
Creator: Fittinghoff, David N.; May, Mark J. & Shepherd, Ronnie

Virtual Institute of Microbial Stress and Survival: Deduction of Stress Response Pathways in Metal and Radionuclide Reducing Microorganisms

Description: The projects application goals are to: (1) To understand bacterial stress-response to the unique stressors in metal/radionuclide contamination sites; (2) To turn this understanding into a quantitative, data-driven model for exploring policies for natural and biostimulatory bioremediation; (3) To implement proposed policies in the field and compare results to model predictions; and (4) Close the experimental/computation cycle by using discrepancies between models and predictions to drive new measurements and construction of new models. The projects science goals are to: (1) Compare physiological and molecular response of three target microorganisms to environmental perturbation; (2) Deduce the underlying regulatory pathways that control these responses through analysis of phenotype, functional genomic, and molecular interaction data; (3) Use differences in the cellular responses among the target organisms to understand niche specific adaptations of the stress and metal reduction pathways; (4) From this analysis derive an understanding of the mechanisms of pathway evolution in the environment; and (5) Ultimately, derive dynamical models for the control of these pathways to predict how natural stimulation can optimize growth and metal reduction efficiency at field sites.
Date: April 17, 2004