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X-Ray Line Measurements with High Efficiency Bragg Crystals

Description: We have studied the focusing properties of two highly oriented pyrolitic graphite (HOPG) spectrometers, which differ in the degree of the mosaic spread: ZYA with a low mosaic spread ({gamma}=0.4 degrees) and ZYH with a large mosaic spread ({gamma}=3.5 degrees). In order to assess the crystal performance for a variety of different experiments, various K{alpha} and K{beta} x-ray lines have been produced using a high-intensity ({approx}>10{sup 17} W/cm{sup 2}) short-pulse ({approx} 100 fs) lase… more
Date: April 1, 2004
Creator: Pak, A; Gregori, G; Knight, J; Campbell, K; Landen, O & Glenzer, S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Graphite Foam Heat Exchangers for Thermal Management

Description: Improved thermal management is needed to increase the power density of electronic and more effectively cool electronic enclosures that are envisioned in future aircraft, spacecraft and surface ships. Typically, heat exchanger cores must increase in size to more effectively dissipate increased heat loads, this would be impossible in many cases, thus improved heat exchanger cores will be required. In this Phase I investigation, MRi aimed to demonstrate improved thermal management using graphite f… more
Date: June 7, 2004
Creator: Klett, J.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Next Generation Nuclear Plant Materials Research and Development Program Plan

Description: The U.S Department of Energy (DOE) has selected the Very High Temperature Reactor (VHTR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production without greenhouse gas emissions. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed, thermal neutron spectrum reactor that will produce electricity and hydrogen in a state-of-the-art thermodynamically efficient manner. T… more
Date: September 1, 2004
Creator: Hayner, G. O. & Shaber, E.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Slurry Molding Technologies for Novel Carbon and Graphite Materials

Description: The Oak Ridge National Laboratory (ORNL) has developed a slurry molding technology for the manufacture of porous, high surface area, carbon fiber composites molecular sieves, and carbon-carbon composite preforms. Potentially, this technology could be applied to the manufacture of a host of novel carbon materials including porous adsorbent carbons, low-pressure drop adsorbent carbon composites, ultra-fine-grained graphite, and carbon fiber reinforced graphite. New opportunities for high surface … more
Date: June 30, 2004
Creator: Burchell, T.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrogen Storage in metal-modified single-walled carbon nanotubes

Description: It has been known for over thirty years that potassium-intercalated graphites can readily adsorb and desorb hydrogen at {approx}1 wt% at 77 K. These levels are much higher than can be attained in pure graphite, owing to a larger thermodynamic enthalpy of adsorption. This increased enthalpy may allow hydrogen sorption at higher temperatures. Potassium has other beneficial effects that enable the design of a new material: (a) Increased adsorption enthalpy in potassium-intercalated graphite compar… more
Date: April 30, 2004
Creator: Ahn, Dr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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3-D Thermal Evaluations for a Fueled Experiment in the Advanced Test Reactor

Description: The DOE Advanced Fuel Cycle Initiative and Generation IV reactor programs are developing new fuel types for use in the current Light Water Reactors and future advanced reactor concepts. The Advanced Gas Reactor program is planning to test fuel to be used in the Next Generation Nuclear Plant (NGNP) nuclear reactor. Preliminary information for assessing performance of the fuel will be obtained from irradiations performed in the Advanced Test Reactor large ''B'' experimental facility. A test confi… more
Date: October 6, 2004
Creator: Ambrosek, Richard G.; Chang, Gray S. & Utterbeck, Debby J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

NANOWIRE CATHODE MATERIAL FOR LITHIUM-ION BATTERIES

Description: This project involved the synthesis of nanowire ã-MnO2 and characterization as cathode material for high-power lithium-ion batteries for EV and HEV applications. The nanowire synthesis involved the edge site decoration nanowire synthesis developed by Dr. Reginald Penner at UC Irvine (a key collaborator in this project). Figure 1 is an SEM image showing ã-MnO2 nanowires electrodeposited on highly oriented pyrolytic graphite (HOPG) electrodes. This technique is unique to other nanowire template s… more
Date: July 21, 2004
Creator: John Olson, PhD
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermocatalytic CO2-Free Production of Hydrogen from Hydrocarbon Fuels

Description: The main objective of this project is the development of an economically viable thermocatalytic process for production of hydrogen and carbon from natural gas or other hydrocarbon fuels with minimal environmental impact. The three major technical goals of this project are: (1) to accomplish efficient production of hydrogen and carbon via sustainable catalytic decomposition of methane or other hydrocarbons using inexpensive and durable carbon catalysts, (2) to obviate the concurrent production o… more
Date: January 30, 2004
Creator: Florida, University of Central
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Industrial Analytics Corporation

Description: The lost foam casting process is sensitive to the properties of the EPS patterns used for the casting operation. In this project Industrial Analytics Corporation (IAC) has developed a new low voltage x-ray instrument for x-ray radiography of very low mass EPS patterns. IAC has also developed a transmitted visible light method for characterizing the properties of EPS patterns. The systems developed are also applicable to other low density materials including graphite foams.
Date: January 30, 2004
Creator: Corporation, Industrial Analytics
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Dissolution of Plutonium Scrub Alloy and Anode Heel Materials in H-Canyon

Description: H-Canyon has a ''gap'' in dissolver operations during the last three months of FY03. One group of material to be processed during the gap is pre-existing scrub alloy material. There are 14 cans of material containing approximately 3.8 kilograms of plutonium. Of the 14 cans, it was anticipated that four cans contain salts, two cans contain anode heel materials, and eight cans contain scrub alloy buttons. H-Canyon desires to process the materials using a flowsheet similar to the SS and C (sand, s… more
Date: April 12, 2004
Creator: Pierce, Robert A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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X-ray photoelectron spectroscopy of negative electrodes from high-power lithium-ion cells showing various levels of power fade

Description: High-power lithium-ion cells for transportation applications are being developed and studied at Argonne National Laboratory. The current generation of cells containing LiNi{sub 0.8}Co{sub 0.15}Al{sub 0.05}O{sub 2}-based cathodes, graphite-based anodes, and LiPF6-based electrolytes show loss of capacity and power during accelerated testing at elevated temperatures. Negative electrode samples harvested from some cells that showed varying degrees of power and capacity fade were examined by X-ray p… more
Date: February 28, 2004
Creator: Herstedt, Marie; Abraham, Daniel P. & Kerr, John B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Gating of Permanent Molds for Aluminum Casting

Description: This report summarizes a two-year project, DE-FC07-011D13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was to determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are prefe… more
Date: January 1, 2004
Creator: Schwam, David; Wallace, John F.; Engle, Tom & Chang, Qingming
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The effect of compression on natural graphite anode performance and matrix conductivity

Description: Anodes for lithium-ion cells were constructed from three types of natural graphite, two coated spherical and one flaky. Anode samples were compressed from 0 to 300 kg/cm2 and studied in half-cells to study the relations between anode density, SEI formation and anode cyclability. The C/25 formation of the SEI layer was found to depend on the nature of the graphite and the anode density. Compression of the uncoated graphite lead to an increased conductivity, but only slight improvements in the ef… more
Date: March 11, 2004
Creator: Striebel, K.A.; Sierra, A.; Shim, J.; Wang, C.-W. & Sastry, A.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

PRODUCTION OF FOAMS, FIBERS AND PITCHES USING A COAL EXTRACTION PROCESS

Description: This Department of Energy National Energy Technology Laboratory sponsored project developed processes for converting coal feedstocks to carbon products, including coal-derived pitch, coke foams and fibers based on solvent extraction processes. A key technology is the use of hydrogenation accomplished at elevated temperatures and pressures to obtain a synthetic coal pitch. Hydrogenation, or partial direct liquefaction of coal, is used to modify the properties of raw coal such that a molten synth… more
Date: June 20, 2004
Creator: Chen, Chong; Kennel, Elliot B.; Magean, Liviu; Stansberry, Pete G.; Stiller, Alfred H. & Zondlo, John W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Design, Construction, and Operation of a Laboratory Scale Reactorfor the Production of High-Purity, Isotopically Enriched Bulksilicon

Description: The design and operation of a recirculating flow reactor designed to convert isotopically enriched silane to polycrystalline Si with high efficiency and chemical purity is described. The starting material is SiF{sub 4}, which is enriched in the desired isotope by a centrifuge method and subsequently converted to silane. In the reactor, the silane is decomposed to silicon on the surface of a graphite starter rod (3 mm diameter) heated to 700-750 C. Flow and gas composition (0.3-0.5% silane in hy… more
Date: December 20, 2004
Creator: Ager, J. W., III; Beeman, J. W.; Hansen, W. L. & Haller, E. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Inverse Process Analysis for the Acquisition of Thermophysical Data

Description: One of the main barriers in the analysis and design of materials processing and industrial applications is the lack of accurate experimental data on the thermophysical properties of materials. To date, the measurement of most of these high-temperature thermophysical properties has often been plagued by temperature lags that are inherent in measurement techniques. These lags can be accounted for with the appropriate mathematical models, reflecting the experimental apparatus and sample region, in… more
Date: October 31, 2004
Creator: Frankel, Jay & Sabau, Adrian
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Formation of Carbon Nanostructures in Cobalt- and Nickel-Doped Carbon Aerogels

Description: We have prepared carbon aerogels (CAs) doped with cobalt or nickel through sol-gel polymerization of formaldehyde with the potassium salt of 2,4-dihydroxybenzoic acid, followed by ion-exchange with M(NO{sub 3}){sub 2} (where M = Co{sup 2+} or Ni{sup 2+}), supercritical drying with liquid CO{sub 2} and carbonization at temperatures between 400 C and 1050 C under an N{sub 2} atmosphere. The nanostructures of these metal-doped carbon aerogels were characterized by elemental analysis, nitrogen adso… more
Date: November 9, 2004
Creator: Fu, R.; Baumann, T. F.; Cronin, S.; Dresselhaus, G.; Dresselhaus, M. & Satcher, J. H. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Ags-Based Super Neutrino Beam Facility Conceptual Design Report

Description: After more than 40 years of operation, the AGS is still at the heart of the Brookhaven hadron accelerator complex. This system of accelerators presently comprises a 200 MeV linac for the pre-acceleration of high intensity and polarized protons, two Tandem Van der Graaffs for the pre-acceleration of heavy ion beams, a versatile Booster that allows for efficient injection of all three types of beams into the AGS and, most recently, the two RHIC collider rings that produce high luminosity heavy io… more
Date: October 8, 2004
Creator: Weng, W. T.; Diwan, M. & Raparia, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Graphite Isotope Ratio Method: A Primer on Estimating Plutonium Production in Graphite Moderated Reactors

Description: The Graphite Isotope Ratio Method (GIRM) is a technique used to estimate the total plutonium production in a graphite-moderated reactor. The cumulative plutonium production in that reactor can be accurately determined by measuring neutron irradiation induced isotopic ratio changes in certain impurity elements within the graphite moderator. The method does not require detailed knowledge of a reactor's operating history, although that knowledge can decrease the uncertainty of the production estim… more
Date: March 25, 2004
Creator: Gesh, Christopher J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Soft X-ray emission spectroscopy of liquids and lithium batterymaterials

Description: Lithium ion insertion into electrode materials is commonly used in rechargeable battery technology. The insertion implies changes in both the crystal structure and the electronic structure of the electrode material. Side-reactions may occur on the surface of the electrode which is exposed to the electrolyte and form a solid electrolyte interface (SEI). The understanding of these processes is of great importance for improving battery performance. The chemical and physical properties of water and… more
Date: October 27, 2004
Creator: Augustsson, Andreas
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Layered Nickel Oxide-Based Cathodes for Lithium Cells: Analysis ofPerformance Loss Mechanisms

Description: Spectroscopic and electrochemical diagnostic measurements are reported for the cell components of a Generation 2 (Gen 2) Li-Ion cell from the US Department of Energy's Advanced Technology Development (ATD) project. The cells are composed of LiNi{sub 0.8}Co{sub 0.15}Al{sub 0.05}O{sub 2} positive electrodes (cathode), carbon graphite anodes and electrolyte consisting of 1.2 M LiPF{sub 6} in EC:EMC 3:7. Fluorophosphates were observed by {sup 19}F and {sup 31}P NMR in the electrolyte obtained from … more
Date: October 1, 2004
Creator: Kerlau, Marie; Reimer, Jeffrey A. & Cairns, Elton J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Diagnostic evaluation of power fade phenomena and calendar lifereduction in high-power lithium-ion batteries

Description: High-power Li-ion cells with graphite anodes and LiNi{sub 0.8}Co{sub 0.15}Al{sub 0.05}O{sub 2} cathodes that were cycled and stored at elevated temperatures showed a significant impedance rise and capacity fade, which were associated primarily with the LiNi{sub 0.8}Co{sub 0.15}Al{sub 0.05}O{sub 2} cathode. A combination of electrochemical, physical, and chemical diagnostic techniques, including Raman, SEM, and current-sensing AFM, was used to characterize the cathodes from these cells in order … more
Date: May 1, 2004
Creator: Kostecki, Robert & McLarnon, Frank
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

3-D Thermal Evaluations for a Fueled Experiment in the Advanced Test Reactor

Description: The DOE Advanced Fuel Cycle Initiative and Generation IV reactor programs are developing new fuel types for use in the current Light Water Reactors and future advanced reactor concepts. The Advanced Gas Reactor program is planning to test fuel to be used in the Next Generation Nuclear Plant (NGNP) nuclear reactor. Preliminary information for assessing performance of the fuel will be obtained from irradiations performed in the Advanced Test Reactor large “B” experimental facility. A test configu… more
Date: October 1, 2004
Creator: Ambrosek, Richard; Chang, Gray & Utterbeck, Debra
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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