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Climate Change: Agencies Should Develop Guidance for Addressing the Effects on Federal Land and Water Resources

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Climate change has implications for the vast land and water resources managed by the Bureau of Land Management (BLM), Forest Service (FS), U.S. Fish and Wildlife Service (FWS), National Oceanic and Atmospheric Administration (NOAA), and National Park Service (NPS). These resources generally occur within four ecosystem types: coasts and oceans, forests, fresh waters, and grasslands and shrublands. GAO ob… more
Date: August 7, 2007
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

X-ray spectroscopic study of the charge state and local orderingof room-temperature ferromagnetic Mn oped ZnO

Description: The charge state and local ordering of Mn doped into a pulsed laser deposited single-phase thin film of ZnO are investigated by using X-ray absorption spectroscopy at the O K-, Mn K- and L-edges, and X-ray emission spectroscopy at the O K- and Mn L-edge. This film is found to be ferromagnetic at room temperature. EXAFS measurement shows that Mn{sup 2+} replaces Zn site in tetrahedral symmetry, and there is no evidence for either metallic Mn or MnO in the film. Upon Mn doping, the top of O 2p va… more
Date: August 7, 2007
Creator: Guo, J.-H.; Gupta, Amita; Sharma, Parmanand; Rao, K.V.; Marcus,M.A.; Dong, C.L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

SERDP ER-1376 Enhancement of In Situ Bioremediation of Energetic Compounds by Coupled Abiotic/Biotic Processes:Final Report for 2004 - 2006

Description: This project was initiated by SERDP to quantify processes and determine the effectiveness of abiotic/biotic mineralization of energetics (RDX, HMX, TNT) in aquifer sediments by combinations of biostimulation (carbon, trace nutrient additions) and chemical reduction of sediment to create a reducing environment. Initially it was hypothesized that a balance of chemical reduction of sediment and biostimulation would increase the RDX, HMX, and TNT mineralization rate significantly (by a combination … more
Date: August 7, 2007
Creator: Szecsody, James E.; Comfort, Steve; Fredrickson, Herbert L.; Boparai, Hardiljeet K.; Devary, Brooks J.; Thompson, Karen T. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Proton hexality from an anomalous flavor U(1) and neutrino masses--Linking to the string scale

Description: We devise minimalistic gauged U(1)_X Froggatt-Nielsen models which at low-energy give rise to the recently suggested discrete gauge Z_6 symmetry, proton hexality, thus stabilizing the proton. Assuming three generations of right-handed neutrinos, with the proper choice of X-charges, we obtain viable neutrino masses. Furthermore, we find scenarios such that no X-charged hidden sector superfields are needed, which from a bottom-up perspective allows the calculation of g_string, g_X and G_SM's … more
Date: August 7, 2007
Creator: Murayama, Hitoshi; Dreiner, Herbi K.; Luhn, Christoph; Murayama, Hitoshi & Thormeiere, Marc
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

ANALYTICAL METHOD FOR MEASURING TOTAL PROTIUM AND TOTAL DEUTERIUM IN A GAS MIXTURE CONTAINING H2, D2,AND HD VIA GAS CHAROMATOGRAPHY

Description: The most common analytical method of identifying and quantifying non-radioactive isotopic species of hydrogen is mass spectrometry. A low mass, high resolution mass spectrometer with adequate sensitivity and stability to identify and quantify hydrogen isotopes in the low ppm range is an expensive, complex instrument. A new analytical technique has been developed that measures both total protium (H) and total deuterium (D) in a gas mixture containing H{sub 2}, D{sub 2}, and HD using an inexpensi… more
Date: August 7, 2007
Creator: Sessions, H
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

NMR structure of the N-terminal domain of the replication initiator protein DnaA

Description: DnaA is an essential component in the initiation of bacterial chromosomal replication. DnaA binds to a series of 9 base pair repeats leading to oligomerization, recruitment of the DnaBC helicase, and the assembly of the replication fork machinery. The structure of the N-terminal domain (residues 1-100) of DnaA from Mycoplasma genitalium was determined by NMR spectroscopy. The backbone r.m.s.d. for the first 86 residues was 0.6 +/- 0.2 Angstrom based on 742 NOE, 50 hydrogen bond, 46 backbone ang… more
Date: August 7, 2007
Creator: Wemmer, David E.; Lowery, Thomas J.; Pelton, Jeffrey G.; Chandonia, John-Marc; Kim, Rosalind; Yokota, Hisao et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Impact of Carbon Structure and Morphology on the ElectrochemicalPerformance of LiFePO4/C Composites

Description: The electrochemical performance of LiFePO{sub 4}/C composites in lithium cells is closely correlated to pressed pellet conductivities measured by AC impedance methods. These composite conductivities are a strong function not only of the amount of carbon, but of its structure and distribution. Ideally, the amount of carbon in composites should be minimal (less than about 2 wt. %) so as not to decrease the energy density unduly. This is particularly important for plug-in hybrid electric vehicle a… more
Date: August 7, 2007
Creator: Doeff, Marca M.; Wilcox, James D.; Yu, Rong; Aumentado, Albert; Marcinek, Marek & Kostecki, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Temporal Representation in Semantic Graphs

Description: A wide range of knowledge discovery and analysis applications, ranging from business to biological, make use of semantic graphs when modeling relationships and concepts. Most of the semantic graphs used in these applications are assumed to be static pieces of information, meaning temporal evolution of concepts and relationships are not taken into account. Guided by the need for more advanced semantic graph queries involving temporal concepts, this paper surveys the existing work involving tempo… more
Date: August 7, 2007
Creator: Levandoski, J J & Abdulla, G M
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Preliminary Report: Results of Computed Tracer Concentrations over Eastern China, South Korea, and Japan for 01 March to 30 May 2007 Daily Simulated Releases from Taiyuan, China

Description: In order to prepare for a proposed long range tracer experiment in China for the spring of 2008 time period, NARAC computed hypothetical PMCH concentrations over Eastern China, South Korea and Japan for simulated releases from Taiyuan, China. Normalized 1 kg of PMCH source strength releases were made twice a day, with wind input from global forecast weather model. We used 6-hour analysis fields valid at the start of each model run, resulting in four wind fields per day. The selected domain enco… more
Date: August 7, 2007
Creator: Vogt, P
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Digital Television: An Overview

Description: This report details the information related to Digital Television service, policy issues, and activities in the 108th, activities, and issues in 109th Congress, and, issues in the 110th congress
Date: August 7, 2007
Creator: Kruger, Lennard G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

LANGEVIN DYNAMICS OF THE TWO STAGE MELTING TRANSITION OF VORTEX MATTER IN Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} IN THE PRESENCE OF STRAIGHT AND OF TILTED COLUMNAR DEFECTS

Description: In this paper we use London Langevin molecular dynamics simulations to investigate the vortex matter melting transition in the highly anisotropic high-temperature superconductor material Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}#14; in the presence of low concentration of columnar defects (CDs). We reproduce with further details our previous results obtained by using Multilevel Monte Carlo simulations that showed that the melting of the nanocrystalline vortex matter occurs in two stages: a … more
Date: August 7, 2007
Creator: Goldschmidt, Yadin Y. & Liu, Jin-Tao
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

Ozone Air Quality Standards: EPA's 2007 Proposed Changes

Description: This report provides background on the National Ambient Air Quality Standard (NAAQS), the process used to establish them, the existing ozone standard, and EPA's proposal, as well as information regarding the potential effects of any revision to the standard.
Date: August 7, 2007
Creator: McCarthy, James E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Scalability of the natural convection shutdown heat removal test facility (NSTF) data to VHTR/NGNP RCCS designs.

Description: Passive safety in the Very High Temperature Reactor (VHTR) is strongly dependent on the thermal performance of the Reactor Cavity Cooling System (RCCS). Scaled experiments performed in the Natural Shutdown Test Facility (NSTF) are to provide data for assessing and/or improving computer code models for RCCS phenomena. Design studies and safety analyses that are to support licensing of the VHTR will rely on these models to achieve a high degree of certainty in predicted design heat removal rate. … more
Date: August 7, 2007
Creator: Vilim, R .B. & Feldman, E. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Strontium Isotopic Composition of Paleozoic Carbonate Rocks in the Nevada Test Site Vicinity, Clark, Lincoln, and Nye Counties, Nevada and Inyo County, California.

Description: Ground water moving through permeable Paleozoic carbonate rocks represents the most likely pathway for migration of radioactive contaminants from nuclear weapons testing at the Nevada Test Site, Nye County, Nevada. The strontium isotopic composition (87Sr/86Sr) of ground water offers a useful means of testing hydrochemical models of regional flow involving advection and reaction. However, reaction models require knowledge of 87Sr/86Sr data for carbonate rock in the Nevada Test Site vicinity, wh… more
Date: August 7, 2007
Creator: Paces, James B.; Peterman, Zell E.; Futa, Kiyoto; Oliver, Thomas A. & Marshall., and Brian D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

NEST-GENERATION TCAP HYDROGEN ISOTOPE SEPARATION PROCESS

Description: A thermal cycling absorption process (TCAP) for hydrogen isotope separation has been in operation at Savannah River Site since 1994. The process uses a hot/cold nitrogen system to cycle the temperature of the separation column. The hot/cold nitrogen system requires the use of large compressors, heat exchanges, valves and piping that is bulky and maintenance intensive. A new compact thermal cycling (CTC) design has recently been developed. This new design uses liquid nitrogen tubes and electric … more
Date: August 7, 2007
Creator: Heung, L; Henry Sessions, H; Anita Poore, A; William Jacobs, W & Christopher Williams, C
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

REMOTE ANALYSIS OF HIGH-TRITIUM-CONTENT WATER

Description: Systems to safely analyze for tritium in moisture collected from glovebox atmospheres are being developed for use at Savannah River Site (SRS) tritium facilities. Analysis results will guide whether the material contains sufficient tritium for economical recovery, or whether it should be stabilized for disposal as waste. In order to minimize potential radiation exposures that could occur in handling and diluting high-tritium-content water, SRS sought alternatives to the process laboratory's rou… more
Date: August 7, 2007
Creator: Diprete, D; Raymond Sigg, R; Leah Arrigo, L & Donald Pak, D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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