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EFFECT OF FUEL IMPURITIES ON FUEL CELL PERFORMANCE AND DURABILITY (open access)

EFFECT OF FUEL IMPURITIES ON FUEL CELL PERFORMANCE AND DURABILITY

A fuel cell is an electrochemical energy conversion device that produces electricity during the combination of hydrogen and oxygen to produce water. Proton exchange membranes fuel cells are favored for portable applications as well as stationary ones due to their high power density, low operating temperature, and low corrosion of components. In real life operation, the use of pure fuel and oxidant gases results in an impractical system. A more realistic and cost efficient approach is the use of air as an oxidant gas and hydrogen from hydrogen carriers (i.e., ammonia, hydrocarbons, hydrides). However, trace impurities arising from different hydrogen sources and production increases the degradation of the fuel cell. These impurities include carbon monoxide, ammonia, sulfur, hydrocarbons, and halogen compounds. The International Organization for Standardization (ISO) has set maximum limits for trace impurities in the hydrogen stream; however fuel cell data is needed to validate the assumption that at those levels the impurities will cause no degradation. This report summarizes the effect of selected contaminants tested at SRNL at ISO levels. Runs at ISO proposed concentration levels show that model hydrocarbon compound such as tetrahydrofuran can cause serious degradation. However, the degradation is only temporary as when the impurity …
Date: September 28, 2010
Creator: Colon-Mercado, H.
System: The UNT Digital Library
ARM Climate Research Facility Monthly Instrument Report August 2010 (open access)

ARM Climate Research Facility Monthly Instrument Report August 2010

The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.
Date: September 28, 2010
Creator: Voyles, J. W.
System: The UNT Digital Library
Final Technical Report for Phase I Award DE-SC0003559 (open access)

Final Technical Report for Phase I Award DE-SC0003559

The Smart Grid opens the door to the development of many companion technologies which will in turn enable the development of a variety of devices for household electricity-consuming appliances that can communicate with it; especially, many major appliance manufacturers (such as Whirlpool and General Electric) have made public commitments to design their appliances to be Smart Grid-compatible over the next several years. Yet during that same time period, customers will purchase many millions of long-lasting appliances which are not compatible with the Smart Grid. This research project's purpose is to bring significant Smart Grid compatibility to previously-installed appliances that were not specifically designed for any Smart Grid communications, in a way that is both economical and attractive for users who want to share in the energy cost savings and reduction of peak power demand opportunities provided by the evolving Smart Grid infrastructure. The focus of this effort is to identify and research smart control solutions which take advantage of the effective strategies of demand-response (DR) communications from utilities [including time-of-day (TOD) and peak-demand pricing options] and function apart from any need for operational changes to be designed into the non-smart appliances. Our Phase I concepts promote technological advancements for enabling …
Date: September 28, 2010
Creator: Blair, Jeff L. & Glenn, Lee J.
System: The UNT Digital Library
Neutronic/Thermalhydraulic Coupling Technigues for Sodium Cooled Fast Reactor Simulations (open access)

Neutronic/Thermalhydraulic Coupling Technigues for Sodium Cooled Fast Reactor Simulations

The objective of this project was to test new coupling algorithms and enable efficient and scalable multi-physics simulations of advanced nuclear reactors, with considerations regarding the implementation of such algorithms in massively parallel environments. Numerical tests were carried out to verify the proposed approach and the examples included some reactor transients. The project was directly related to the Sodium Fast Reactor program element of the Generation IV Nuclear Energy Systems Initiative and the Advanced Fuel cycle Initiative, and, supported the requirement of high-fidelity simulation as a mean of achieving the goals of the presidential Global Nuclear Energy Partnership (GNEP) vision.
Date: September 28, 2010
Creator: Ragusa, Jean; Siegel, Andrew & Ruggieri, Jean-Michel
System: The UNT Digital Library
Advances and Current Challenges in the Theory of Zonal-Flow Generation (open access)

Advances and Current Challenges in the Theory of Zonal-Flow Generation

Some remarks are made about the use of modern statistical formalism in the calculation of the zonal-flow growth rate and the backreaction of zonal flows on drift waves.
Date: September 28, 2010
Creator: Krommes, John E.
System: The UNT Digital Library
PRELIMINARY EVALUATION OF DWPF IMPACTS OF BORIC ACID USE IN CESIUM STRIP FOR SWPF AND MCU (open access)

PRELIMINARY EVALUATION OF DWPF IMPACTS OF BORIC ACID USE IN CESIUM STRIP FOR SWPF AND MCU

A new solvent system is being evaluated for use in the Modular Caustic-Side Solvent Extraction Unit (MCU) and in the Salt Waste Processing Facility (SWPF). The new system includes the option to replace the current dilute nitric acid strip solution with boric acid. To support this effort, the impact of using 0.01M, 0.1M, 0.25M and 0.5M boric acid in place of 0.001M nitric acid was evaluated for impacts on the DWPF facility. The evaluation only covered the impacts of boric acid in the strip effluent and does not address the other changes in solvents (i.e., the new extractant, called MaxCalix, or the new suppressor, guanidine). Boric acid additions may lead to increased hydrogen generation during the SRAT and SME cycles as well as change the rheological properties of the feed. The boron in the strip effluent will impact glass composition and could require each SME batch to be trimmed with boric acid to account for any changes in the boron from strip effluent additions. Addition of boron with the strip effluent will require changes in the frit composition and could lead to changes in melt behavior. The severity of the impacts from the boric acid additions is dependent on the …
Date: September 28, 2010
Creator: Stone, M.
System: The UNT Digital Library
Implicit Methods for the Magnetohydrodynamic Description of Magnetically Confined Plasmas (open access)

Implicit Methods for the Magnetohydrodynamic Description of Magnetically Confined Plasmas

Implicit algorithms are essential for predicting the slow growth and saturation of global instabilities in today’s magnetically confined fusion plasma experiments. Present day algorithms for obtaining implicit solutions to the magnetohydrodynamic (MHD) equations for highly magnetized plasma have their roots in algorithms used in the 1960s and 1970s. However, today’s computers and modern linear and non‐linear solver techniques make practical much more comprehensive implicit algorithms than were previously possible. Combining these advanced implicit algorithms with highly accurate spatial representations of the vector fields describing the plasma flow and magnetic fields and with improved methods of calculating anisotropic thermal conduction now makes possible simulations of fusion experiments using realistic values of plasma parameters and actual configuration geometry.
Date: September 28, 2010
Creator: Jardin, S. C.
System: The UNT Digital Library
Thermodynamic Data for Geochemical Modeling of Carbonate Reactions Associated with CO2 Sequestration – Literature Review (open access)

Thermodynamic Data for Geochemical Modeling of Carbonate Reactions Associated with CO2 Sequestration – Literature Review

Permanent storage of anthropogenic CO2 in deep geologic formations is being considered as a means to reduce the concentration of atmospheric CO2 and thus its contribution to global climate change. To ensure safe and effective geologic sequestration, numerous studies have been completed of the extent to which the CO2 migrates within geologic formations and what physical and geochemical changes occur in these formations when CO2 is injected. Sophisticated, computerized reservoir simulations are used as part of field site and laboratory CO2 sequestration studies. These simulations use coupled multiphase flow-reactive chemical transport models and/or standalone (i.e., no coupled fluid transport) geochemical models to calculate gas solubility, aqueous complexation, reduction/oxidation (redox), and/or mineral solubility reactions related to CO2 injection and sequestration. Thermodynamic data are critical inputs to modeling geochemical processes. The adequacy of thermodynamic data for carbonate compounds has been identified as an important data requirement for the successful application of these geochemical reaction models to CO2 sequestration. A review of thermodynamic data for CO2 gas and carbonate aqueous species and minerals present in published data compilations and databases used in geochemical reaction models was therefore completed. Published studies that describe mineralogical analyses from CO2 sequestration field and natural analogue sites and …
Date: September 28, 2010
Creator: Krupka, Kenneth M.; Cantrell, Kirk J. & McGrail, B. Peter
System: The UNT Digital Library
Assessment of the Use of Nitrogen Trifluoride for Purifying Coolant and Heat Transfer Salts in the Fluoride Salt-Cooled High-Temperature Reactor (open access)

Assessment of the Use of Nitrogen Trifluoride for Purifying Coolant and Heat Transfer Salts in the Fluoride Salt-Cooled High-Temperature Reactor

This report provides an assessment of the use of nitrogen trifluoride for removing oxide and water-caused contaminants in the fluoride salts that will be used as coolants in a molten salt cooled reactor.
Date: September 28, 2010
Creator: Scheele, Randall D. & Casella, Andrew M.
System: The UNT Digital Library
International Clean Energy Coalition (open access)

International Clean Energy Coalition

In 2003, the National Association of Regulatory Utility Commissioners (NARUC) and National Energy Technology Laboratories (NETL) collaboratively established the International Clean Energy Coalition (ICEC). The coalition consisting of energy policy-makers, technologists, and financial institutions was designed to assist developing countries in forming and supporting local approaches to greenhouse gas mitigation within the energy sector. ICEC's work focused on capacity building and clean energy deployment in countries that rely heavily on fossil-based electric generation. Under ICEC, the coalition formed a steering committee consisting of NARUC members and held a series of meetings to develop and manage the workplan and define successful outcomes for the projects. ICEC identified India as a target country for their work and completed a country assessment that helped ICEC build a framework for discussion with Indian energy decisionmakers including two follow-on in-country workshops. As of the conclusion of the project in 2010, ICEC had also conducted outreach activities conducted during United Nations Framework Convention on Climate Change (UNFCCC) Ninth Conference of Parties (COP 9) and COP 10. The broad goal of this project was to develop a coalition of decision-makers, technologists, and financial institutions to assist developing countries in implementing affordable, effective and resource appropriate technology and …
Date: September 28, 2010
Creator: Skootsky, Erin; Gardner, Matt & Flansburgh, Bevan
System: The UNT Digital Library
Physical Property Analysis and Report for Sediments at 100-BC-5 Operable Unit, Boreholes C7505, C7506, C7507, and C7665 (open access)

Physical Property Analysis and Report for Sediments at 100-BC-5 Operable Unit, Boreholes C7505, C7506, C7507, and C7665

Between October 14, 2009 and February 22, 2010 sediment samples were received from 100-BC Decision Unit for geochemical studies. This is an analytical data report for sediments received from CHPRC at the 100 BC 5 OU. The analyses for this project were performed at the 325 building located in the 300 Area of the Hanford Site. The analyses were performed according to Pacific Northwest National Laboratory (PNNL) approved procedures and/or nationally recognized test procedures. The data sets include the sample identification numbers, analytical results, estimated quantification limits (EQL), and quality control data. The preparatory and analytical quality control requirements, calibration requirements, acceptance criteria, and failure actions are defined in the on-line QA plan 'Conducting Analytical Work in Support of Regulatory Programs' (CAW). This QA plan implements the Hanford Analytical Services Quality Assurance Requirements Documents (HASQARD) for PNNL.
Date: September 28, 2010
Creator: Lindberg, Michael J.
System: The UNT Digital Library
Field Summary Report for Remedial Investigation of Hanford Site Releases to the Columbia River, Hanford Site, Washington (open access)

Field Summary Report for Remedial Investigation of Hanford Site Releases to the Columbia River, Hanford Site, Washington

This report documents field activity associated with the collection, preparation, and shipment of fish samples. The purpose of the report is to describe the sampling locations, identify samples collected, and describe any modifications and additions made to the sampling and analysis plan.
Date: September 28, 2010
Creator: Hulstrom, L. C.
System: The UNT Digital Library
Rare Plant Restoration and Monitoring at Lawrence Livermore National Laboratory, Site 300, Project Progress Report, Fiscal Year 2005 and 2006. (open access)

Rare Plant Restoration and Monitoring at Lawrence Livermore National Laboratory, Site 300, Project Progress Report, Fiscal Year 2005 and 2006.

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Date: September 28, 2010
Creator: Paterson, L E; Carlsen, T M; Afaro, T M & Espeland, E
System: The UNT Digital Library
Soil Water Retention and Relative Permeability for Full Range of Saturation (open access)

Soil Water Retention and Relative Permeability for Full Range of Saturation

Common conceptual models for unsaturated flow often rely on the oversimplified representation of medium pores as a bundle of cylindrical capillaries and assume that the matric potential is attributed to capillary forces only. The adsorptive surface forces are ignored. It is often assumed that aqueous flow is negligible when a soil is near or at the residual water content. These models are successful at high and medium water contents but often give poor results at low water contents. These models do not apply to conditions at which water content is less than the residual water content. We extend the lower bound of existing water-retention functions and conductivity models from residual water content to the oven-dry condition (i.e., zero water content) by defining a state-dependent, residual-water content for a soil drier than a critical value. Furthermore, a hydraulic conductivity model for smooth uniform spheres was modified by introducing a correction factor to describe the film flow-induced hydraulic conductivity for natural porous media. The total unsaturated hydraulic conductivity is the sum of those due to capillary and film flow. The extended retention and conductivity models were verified with six datasets from the literature. Results show that, when the soil is at high …
Date: September 28, 2010
Creator: Zhang, Z. F.
System: The UNT Digital Library
Y-12 81-10 Area Site Characterization Report 5095-SR-01-1 (open access)

Y-12 81-10 Area Site Characterization Report 5095-SR-01-1

5095-SR-01-1 Y-12 81-10 Area Site Characterization Report
Date: September 28, 2010
Creator: King, D. A.
System: The UNT Digital Library
Final Technical Summary: Center for Fundamental and Applied Research in Nanostructured and Lightweight Materials (open access)

Final Technical Summary: Center for Fundamental and Applied Research in Nanostructured and Lightweight Materials

The core projects for this DOE-sponsored Center at Michigan Tech have focused on several of the materials problems identified by the NAS. These include: new electrode materials, enhanced PEM materials, lighter and more effective bipolar plates, and improvement of the carbon used as a current carrier. This project involved fundamental and applied research in the development and testing of lightweight and nanostructured materials to be used in fuel cell applications and for chemical synthesis. The advent of new classes of materials engineered at the nanometer level can produce materials that are lightweight and have unique physical and chemical properties. The grant was used to obtain and improve the equipment infrastructure to support this research and also served to fund seven research projects. These included: 1. Development of lightweight, thermally conductive bipolar plates for improved thermal management in fuel cells; 2. Exploration of pseudomorphic nanoscale overlayer bimetallic catalysts for fuel cells; 3. Development of hybrid inorganic/organic polymer nanocomposites with improved ionic and electronic properties; 4. Development of oriented polymeric materials for membrane applications; 5. Preparation of a graphitic carbon foam current collectors; 6. The development of lightweight carbon electrodes using graphitic carbon foams for battery and fuel cell applications; and 7. …
Date: September 28, 2010
Creator: Mullins, Michael; Rogers, Tony; King, Julia; Keith, Jason; Corilsen, Bahne; Allen, Jeffrey et al.
System: The UNT Digital Library
Child Well-Being and Noncustodial Fathers (open access)

Child Well-Being and Noncustodial Fathers

The structure of a family plays an important role in children's well-being. A contributing factor to the high rates of child poverty over the long-term, and the increase in child poverty during the period from 2001-2007, was the increasing likelihood of children living in families headed by a single female. This report covers information on the background including social and economic trends, selected federal programs, federal policy options, and related information.
Date: September 28, 2010
Creator: Solomon-Fears, Carmen; Falk, Gene & Fernandes-Alcantara, Adrienne L.
System: The UNT Digital Library
Individual Development Accounts (IDAs): Background and Current Legislation for Federal Grant Programs to Help Low-Income Families Save (open access)

Individual Development Accounts (IDAs): Background and Current Legislation for Federal Grant Programs to Help Low-Income Families Save

This report describes IDA programs funded by two major federal grants: the Assets for Independence (AFI) Act of 1998 and the Temporary Assistance for Needy Families (TANF) program created in the 1996 welfare reform law.
Date: September 28, 2010
Creator: Falk, Gene
System: The UNT Digital Library
The Endangered Species Act (ESA) in the 111th Congress: Conflicting Values and Difficult Choices (open access)

The Endangered Species Act (ESA) in the 111th Congress: Conflicting Values and Difficult Choices

This report discusses oversight issues and legislation introduced in the 111th Congress to address Endangered Species Act (ESA) implementation and management of endangered and threatened species.
Date: September 28, 2010
Creator: Buck, Eugene H.; Corn, M. Lynne; Sheikh, Pervaze A.; Meltz, Robert & Alexander, Kristina
System: The UNT Digital Library
Head Start: Undercover Testing Finds Fraud and Abuse at Selected Head Start Centers (open access)

Head Start: Undercover Testing Finds Fraud and Abuse at Selected Head Start Centers

A letter report issued by the Government Accountability Office with an abstract that begins "The Head Start program provides child development services primarily to low-income families and their children. Federal law allows up to 10 percent of families to have incomes above 130 percent of the poverty line--GAO refers to them as over-income families. Families with incomes below 130 percent of the poverty line, or that meet certain other criteria, are referred to as under-income families. Nearly 1 million children a year participate in Head Start, and the American Recovery and Reinvestment Act provided an additional $2.1 billion. GAO received hotline tips alleging fraud by grantees. In response, GAO investigated the allegations, conducted undercover tests to determine if other centers were committing fraud, and documented instances where potentially eligible children were put on Head Start wait lists. On May 18, 2010 GAO testified on the preliminary results of the ongoing investigation. This report reiterates the findings disclosed in GAO's May testimony, and discusses new findings related to specific fraud allegations at two Head Start grantees. Since GAO's May testimony, HHS has taken a number of actions to address identified weaknesses, such as implementing a fraud hotline. HHS also indicated that …
Date: September 28, 2010
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Taiwan: Major U.S. Arms Sales Since 1990 (open access)

Taiwan: Major U.S. Arms Sales Since 1990

This CRS Report discusses U.S. security assistance for Taiwan, formally called the Republic of China (ROC), particularly policy issues for Congress. It also lists sales of major defense articles and services to Taiwan, as approved by the President and notified to Congress since 1990. This report uses a variety of unclassified consultations and citations in the United States and Taiwan.
Date: September 28, 2010
Creator: Kan, Shirley A.
System: The UNT Digital Library
Waste, Fraud, and Abuse in Agency Travel Card Programs (open access)

Waste, Fraud, and Abuse in Agency Travel Card Programs

The Travel and Transportation Reform Act of 1998 required federal employees to use travel charge cards to pay for the expenses of official government travel. The dollar volume of travel card transaction has nearly doubled from FY1999 to FY2009. This report discusses card misuse committed by federal employees, and Congress's response, which has included hearings and legislation intended to enhance travel card management and oversight.
Date: September 28, 2010
Creator: Hatch, Garrett
System: The UNT Digital Library
Beginning and End of the Terms of United States Senators Chosen to Fill Senate Vacancies (open access)

Beginning and End of the Terms of United States Senators Chosen to Fill Senate Vacancies

This report discusses the procedures for when a Senator is chosen to fill a Senate vacancy during a session of Congress, i.e., when the appointed Senator can begin his or her term of office, and how long the Senator remains in office (until the new "Senator-elect" is sworn in and seated by the Senate).
Date: September 28, 2010
Creator: Maskell, Jack
System: The UNT Digital Library
Navy Ford (CVN-78) Class Aircraft Carrier Program: Background and Issues for Congress (open access)

Navy Ford (CVN-78) Class Aircraft Carrier Program: Background and Issues for Congress

CVN-78, CVN-79, and CVN-80 are the first three ships in the Navy's new Gerald R. Ford (CVN-78) class of nuclear-powered aircraft carriers (CVNs). This report the procurement schedules, budgets, and funding for each of these ships, as well as potential oversight issues for Congress.
Date: September 28, 2010
Creator: O'Rourke, Ronald
System: The UNT Digital Library