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Lead In Tap Water: CDC Public Health Communications Need Improvement (open access)

Lead In Tap Water: CDC Public Health Communications Need Improvement

A letter report issued by the Government Accountability Office with an abstract that begins "In February 2004, the Centers for Disease Control and Prevention (CDC) was asked to assess the effects of elevated lead levels in tap water on Washington, D.C., residents. In April 2004, CDC published the results. However, an inaccurate statement and incomplete descriptions of the limitations of the analyses resulted in confusion about CDC's intended message. GAO was asked to examine (1) CDC's actions to clarify its published results and communicate current knowledge about the contribution of lead in tap water to elevated blood lead levels (BLL) in children and (2) CDC's changes to its procedures to improve the clarity of the information in its public health communications. GAO reviewed CDC communication policies and procedures and interviewed CDC officials."
Date: March 14, 2011
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
The Marines' Expeditionary Fighting Vehicle (EFV): Background and Issues for Congress (open access)

The Marines' Expeditionary Fighting Vehicle (EFV): Background and Issues for Congress

This report discusses the Expeditionary Fighting Vehicle (EFV), which is an armored amphibious vehicle program that originated two decades ago to replace the 1970s-era Amphibious Assault Vehicle (AAV). The EFV has experienced a variety of developmental difficulties, which this report explores. This report also discusses potential related issues for Congress.
Date: March 14, 2011
Creator: Feickert, Andrew
Object Type: Report
System: The UNT Digital Library
U.S. Trade Deficit and the Impact of Changing Oil Prices (open access)

U.S. Trade Deficit and the Impact of Changing Oil Prices

This report provides an estimate of the initial impact of the changing oil prices on the United States' merchandise trade deficit.
Date: March 14, 2011
Creator: Jackson, James K.
Object Type: Report
System: The UNT Digital Library
Congressional Gold Medals, 1776-2010 (open access)

Congressional Gold Medals, 1776-2010

Members of Congress and their staff frequently ask questions concerning the nature, history, and contemporary application of the process for awarding Gold Medals. This report responds to congressional inquiries concerning this process, and includes a historical examination and chronological list of these awards. It is intended to assist Members of Congress and staff in their consideration of future Gold Medal proposals, and will be updated as Gold Medals are approved.
Date: March 14, 2011
Creator: Glassman, Matthew Eric
Object Type: Report
System: The UNT Digital Library
Federal Disaster Recovery Programs: Brief Summaries (open access)

Federal Disaster Recovery Programs: Brief Summaries

This report summarizes federal disaster assistance programs for use by Members of Congress and their staff in helping address the needs of constituents. This report includes a list of CRS reports on disaster assistance and assistance for victims of recent hurricanes. It also includes a list of federal agencies' websites that were established to provide information on disaster responses, updates on recovery efforts, and resources on federal assistance programs.
Date: March 14, 2011
Creator: Torsell, Carolyn V.
Object Type: Report
System: The UNT Digital Library
Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress (open access)

Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

This report discusses issues Congress faces regarding the Navy's proposed FY2012 budget, particularly as relating to destroyer procurement plans and programs.
Date: March 14, 2011
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
U.S. Trade Deficit and the Impact of Changing Oil Prices (open access)

U.S. Trade Deficit and the Impact of Changing Oil Prices

This report provides an estimate of the initial impact of the changing oil prices on the nation's merchandise trade deficit.
Date: March 14, 2011
Creator: Jackson, James K.
Object Type: Report
System: The UNT Digital Library
Multilateral Development Banks: How the United States Makes and Implements Policy (open access)

Multilateral Development Banks: How the United States Makes and Implements Policy

This report analyzes how the United States makes policy towards the multilateral development banks (MDBs) and identifies ways by which Congress can shape U.S. policy and influence the activities of the banks themselves.
Date: March 14, 2011
Creator: Nelson, Rebecca M. & Weiss, Martin A.
Object Type: Report
System: The UNT Digital Library
Texas Attorney General Opinion: GA-0848 (open access)

Texas Attorney General Opinion: GA-0848

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification: Whether the State Board of Education may contract to pay attorney fees out of the corpus of the Permanent School Fun without an appropriation specifically for that purpose (RQ-0920-GA)
Date: March 14, 2011
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
U.S. Tsunami Programs: A Brief Overview (open access)

U.S. Tsunami Programs: A Brief Overview

None
Date: March 14, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Performance of "Moth Eye" Anti-Reflective Coatings for Solar Cell Applications (open access)

Performance of "Moth Eye" Anti-Reflective Coatings for Solar Cell Applications

An inexpensive, effective anti-reflective coating (ARC) has been developed at the University of Florida to significantly enhance the absorption of light by silicon in solar cells. This coating has nano-scale features, and its microstructure mimics that of various night active insects (e.g. a moth's eye). It is a square array of pillars, each about 700 nm high and having a diameter of about 300 nm. Samples of silicon having this coating were exposed either to various combinations of either elevated temperature and humidity or to gamma irradiation ({sup 60}Co) at the Savannah River National Laboratory, or to a broad spectrum ultraviolet light and to a 532 nm laser light at the University of Florida. The anti-reflective properties of the coatings were unaffected by any of these environmental stresses, and the microstructure of the coating was also unaffected. In fact, the reflectivity of the gamma irradiated ARC became lower (advantageous for solar cell applications) at wavelengths between 400 and 1000 nm. These results show that this coating is robust and should be tested in actual systems exposed to either weather or a space environment. Structural details of the ARCs were studied to optimize their performance. Square arrays performed better than hexagonal …
Date: March 14, 2011
Creator: Clark, E.; Kane, M. & Jiang, P.
Object Type: Report
System: The UNT Digital Library
Phylogeny and comparative genome analysis of a Basidiomycete fungi (open access)

Phylogeny and comparative genome analysis of a Basidiomycete fungi

Fungi of the phylum Basidiomycota, make up some 37percent of the described fungi, and are important from the perspectives of forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, plant pathogenic rusts and smuts, and some human pathogens. To better understand these important fungi, we have undertaken a comparative genomic analysis of the Basidiomycetes with available sequenced genomes. We report a phylogeny that sheds light on previously unclear evolutionary relationships among the Basidiomycetes. We also define a `core proteome? based on protein families conserved in all Basidiomycetes. We identify key expansions and contractions in protein families that may be responsible for the degradation of plant biomass such as cellulose, hemicellulose, and lignin. Finally, we speculate as to the genomic changes that drove such expansions and contractions.
Date: March 14, 2011
Creator: Riley, Robert W.; Salamov, Asaf; Grigoriev, Igor & Hibbett, David
Object Type: Article
System: The UNT Digital Library
Quarkonium production in high energyproton-proton and proton-nucleus collisions (open access)

Quarkonium production in high energyproton-proton and proton-nucleus collisions

We present a brief overview of the most relevant current issues related to quarkonium production in high energy proton-proton and proton-nucleus collisions along with some perspectives. After reviewing recent experimental and theoretical results on quarkonium production in pp and pA collisions, we discuss the emerging field of polarization studies. Afterwards, we report on issues related to heavy-quark production, both in pp and pA collisions, complemented by AA collisions. To put the work in broader perpectives, we emphasize the need for new observables to investigate the quarkonium production mechanisms and reiterate the qualities that make quarkonia a unique tool for many investigations in particle and nuclear physics.
Date: March 14, 2011
Creator: del Valle, Z. C.; Corcella, G.; Fleuret, F.; Ferreiro, E. G.; Kartvelishvili, V.; Kopeliovich, B. et al.
Object Type: Article
System: The UNT Digital Library
VERIFICATION OF THE DEFENSE WASTE PROCESSING FACILITY'S (DWPF) PROCESS DIGESTION METHOD FOR THE SLUDGE BATCH 7A QUALIFICATION SAMPLE (open access)

VERIFICATION OF THE DEFENSE WASTE PROCESSING FACILITY'S (DWPF) PROCESS DIGESTION METHOD FOR THE SLUDGE BATCH 7A QUALIFICATION SAMPLE

For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs confirmation of the applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples. DWPF SRAT samples are typically dissolved using a room temperature HF-HNO{sub 3} acid dissolution (i.e., DWPF Cold Chem Method, see DWPF Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICP-AES). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestions of Sludge Batch 7a (SB7a) SRAT Receipt and SB7a SRAT Product samples. The SB7a SRAT Receipt and SB7a SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constituates the SB7a Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 6 (SB6), to form the Sb7a Blend composition.
Date: March 14, 2011
Creator: Click, D.; Edwards, T.; Jones, M. & Wiedenman, B.
Object Type: Report
System: The UNT Digital Library
Low-Energy Run of Fermilab Electron Cooler's Beam Generation System (open access)

Low-Energy Run of Fermilab Electron Cooler's Beam Generation System

In the context of the evaluation of possibly using the Fermilab Electron Cooler for the proposed low-energy RHIC run at BNL, operating the cooler at 1.6 MeV electron beam energy was tested in a short beam line configuration. The main conclusion of this feasibility study is that the cooler's beam generation system is suitable for BNL needs. The beam recirculation was stable for all tested parameters. In particular, a beam current of 0.38 A was achieved with the cathode magnetic field up to the maximum value presently available of 250 G. The energy ripple was measured to be 40 eV. A striking difference with running the 4.3 MeV beam (nominal for operation at FNAL) is that no unprovoked beam recirculation interruptions were observed. Electron cooling proposed to increase the luminosity of the RHIC collider for heavy ion beam energies below 10 GeV/nucleon [1] needs a good quality, 0.9-5 MeV electron beam. Preliminary design studies indicate that the scheme of the Recycler's electron cooler at FNAL is suitable for low-energy RHIC cooling and most parts of the cooler can be re-used after the end of the Tevatron Run II. To analyze issues related to the generation of the electron beam in …
Date: March 14, 2011
Creator: Prost, L. R.; Shemyakin, A.; Fedotov, A. & Kewisch, J.
Object Type: Article
System: The UNT Digital Library
2010 Dry and 2009 - 2010 Wet Season Branchiopod Survey Report, Site 300 (open access)

2010 Dry and 2009 - 2010 Wet Season Branchiopod Survey Report, Site 300

Lawrence Livermore National Laboratory (LLNL) requested that Condor Country Consulting, Inc. (CCCI) perform wet season surveys and manage the dry season sampling for listed branchiopods in two ponded locations within the Site 300 Experimental Test Site. Site 300 is located in Alameda and San Joaquin Counties, located between the Cities of Livermore and Tracy. The two pool locations have been identified for possible amphibian enhancement activities in support of the Compensation Plan for impacts tied to the Building 850 soil clean-up project. The Building 850 project design resulted in formal consultation with the U.S. Fish and Wildlife Service (USFWS) as an amendment (File 81420-2009-F-0235) to the site-wide Biological Opinion (BO) (File 1-1-02-F-0062) in the spring of 2009 and requires mitigation for the California tiger salamander (AMCA, Ambystoma californiense) and California red-legged frog (CRLF, Rana draytonii) habitat loss. Both pools contain breeding AMCA, but do not produce metamorphs due to limited hydroperiod. The pool to the southeast (Pool BC-FS-2) is the preferred site for amphibian enhancement activities, and the wetland to northwest (Pool OA-FS-1) is the alternate location for enhancement. However, prior to enhancement, LLNL has been directed by USFWS (BO Conservation Measure 17 iii) to 'conduct USFWS protocol-level branchiopod surveys …
Date: March 14, 2011
Creator: Dexter, W.
Object Type: Report
System: The UNT Digital Library
Calibration of the modulation transfer function of surface profilometers with binary pseudo-random test standards: expanding the application range (open access)

Calibration of the modulation transfer function of surface profilometers with binary pseudo-random test standards: expanding the application range

A modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays [Proc. SPIE 7077-7 (2007), Opt. Eng. 47, 073602 (2008)] has been proven to be an effective MTF calibration method for a number of interferometric microscopes and a scatterometer [Nucl. Instr. and Meth. A616, 172 (2010)]. Here we report on a further expansion of the application range of the method. We describe the MTF calibration of a 6 inch phase shifting Fizeau interferometer. Beyond providing a direct measurement of the interferometer's MTF, tests with a BPR array surface have revealed an asymmetry in the instrument's data processing algorithm that fundamentally limits its bandwidth. Moreover, the tests have illustrated the effects of the instrument's detrending and filtering procedures on power spectral density measurements. The details of the development of a BPR test sample suitable for calibration of scanning and transmission electron microscopes are also presented. Such a test sample is realized as a multilayer structure with the layer thicknesses of two materials corresponding to BPR sequence. The investigations confirm the universal character of the method that makes it applicable to a large variety of metrology instrumentation with spatial wavelength bandwidths from a few nanometers to hundreds of …
Date: March 14, 2011
Creator: Yashchuk, Valeriy V.; Anderson, Erik H.; Barber, Samuel K.; Bouet, Nathalie; Cambie, Rossana; Conley, Raymond et al.
Object Type: Article
System: The UNT Digital Library
Technical Data to Justify Full Burnup Credit in Criticality Safety Licensing Analysis (open access)

Technical Data to Justify Full Burnup Credit in Criticality Safety Licensing Analysis

Enercon Services, Inc. (ENERCON) was requested under Task Order No.2 to identify scientific and technical data needed to benchmark and justify Full Burnup Credit, which adds 16 fission products and 4 minor actinides1 to Actinide-Only burnup credit. The historical perspective for Full Burnup Credit is discussed, and interviews of organizations participating in burnup credit activities are summarized as a basis for identifying additional data needs and making recommendation. Input from burnup credit participants representing two segments of the commercial nuclear industry is provided. First, the Electric Power Research Institute (EPRI) has been very active in the development of Full Burnup Credit, representing the interests of nuclear utilities in achieving capacity gains for storage and transport casks. EPRI and its utility customers are interested in a swift resolution of the validation issues that are delaying the implementation of Full Burnup Credit [EPRI 2010b]. Second, used nuclear fuel storage and transportation Cask Vendors favor improving burnup credit beyond Actinide-Only burnup credit, although their discussion of specific burnup credit achievements and data needs was limited citing business sensitive and technical proprietary concerns. While Cask Vendor proprietary items are not specifically identified in this report, the needs of all nuclear industry participants are reflected …
Date: March 14, 2011
Creator: Enercon Services, Inc.
Object Type: Report
System: The UNT Digital Library
Hydrogen Production by Water Dissociation Using Ceramic Membranes - Annual Report for FY 2010. (open access)

Hydrogen Production by Water Dissociation Using Ceramic Membranes - Annual Report for FY 2010.

The objective of this project is to develop dense ceramic membranes that can produce hydrogen via coal/coal gas-assisted water dissociation without using an external power supply or circuitry. This project grew from an effort to develop a dense ceramic membrane for separating hydrogen from gas mixtures such as those generated during coal gasification, methane partial oxidation, and water-gas shift reactions. That effort led to the development of various cermet (i.e., ceramic/metal composite) membranes that enable hydrogen production by two methods. In one method, a hydrogen transport membrane (HTM) selectively removes hydrogen from a gas mixture by transporting it through either a mixed protonic/electronic conductor or a hydrogen transport metal. In the other method, an oxygen transport membrane (OTM) generates hydrogen mixed with steam by removing oxygen that is generated through water splitting. This project focuses on the development of OTMs that efficiently produce hydrogen via the dissociation of water. Supercritical boilers offer very high-pressure steam that can be decomposed to provide pure hydrogen using OTMs. Oxygen resulting from the dissociation of steam can be used for coal gasification, enriched combustion, or synthesis gas production. Hydrogen and sequestration-ready CO{sub 2} can be produced from coal and steam by using the membrane …
Date: March 14, 2011
Creator: Balachandran, U.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Lu, Y.; Park, C. Y. et al.
Object Type: Report
System: The UNT Digital Library
Literature Review on the Effects of Prescription Fire on theEcology of Site 300 (open access)

Literature Review on the Effects of Prescription Fire on theEcology of Site 300

Lawrence Livermore National Laboratory has historically conducted prescription burns across approximately 2,000 acres of Site 300 on an annual basis to safeguard test facilities and operations from the risk of wildfire encroachment. Prescription burns began in 1960, and although fire frequency varies among the designated burn areas, all have been burned at least once. A patchwork of native perennial grassland communities and associated special-status plant and animal populations occur onsite in many areas that have been receiving these treatments. Because the size and locations of prescription burns may shift in coming years, an evaluation is warranted to determine how these shifts may affect listed biota, including rare plants, and the distinct ecological conditions present on the site. This report presents the results of a literature review conducted by ICF International (ICF) to collect basic information on native perennial grasslands in California, the influence of fire on these grasslands, and management tools for restoring and maintaining them. The objective of this study was to review the scientific literature on California native grasslands and summarize the current state of knowledge pertaining to the possible effects -- both beneficial and detrimental -- of prescribed fire on the ecology of Site 300. The results …
Date: March 14, 2011
Creator: Preston, R
Object Type: Report
System: The UNT Digital Library
HYDROGEN CONCENTRATIONS DURING STORAGE OF 3013 OXIDE SAMPLES (open access)

HYDROGEN CONCENTRATIONS DURING STORAGE OF 3013 OXIDE SAMPLES

As part of a surveillance program intended to ensure the safe storage of plutonium bearing nuclear materials in the Savannah River Site (SRS) K-Area Materials Storage (KAMS), samples of these materials are shipped to Savannah River National Laboratory (SRNL) for analysis. These samples are in the form of solids or powders which will have absorbed moisture. Potentially flammable hydrogen gas is generated due to radiolysis of the moisture. The samples are shipped for processing after chemical analysis. To preclude the possibility of a hydrogen deflagration or detonation inside the shipping containers, the shipping times are limited to ensure that hydrogen concentration in the vapor space of every layer of confinement is below the lower flammability limit of 4 volume percent (vol%). This study presents an analysis of the rate of hydrogen accumulation due to radiolysis and calculation of allowable shipping times for typical KAMS materials.
Date: March 14, 2011
Creator: Hensel, S.; Askew, N. & Laurinat, J.
Object Type: Article
System: The UNT Digital Library
High-Resolution Spore Coat Architecture and Assembly of Bacillus Spores (open access)

High-Resolution Spore Coat Architecture and Assembly of Bacillus Spores

Elucidating the molecular architecture of bacterial and cellular surfaces and its structural dynamics is essential to understanding mechanisms of pathogenesis, immune response, physicochemical interactions, environmental resistance, and provide the means for identifying spore formulation and processing attributes. I will discuss the application of in vitro atomic force microscopy (AFM) for studies of high-resolution coat architecture and assembly of several Bacillus spore species. We have demonstrated that bacterial spore coat structures are phylogenetically and growth medium determined. We have proposed that strikingly different species-dependent coat structures of bacterial spore species are a consequence of sporulation media-dependent nucleation and crystallization mechanisms that regulate the assembly of the outer spore coat. Spore coat layers were found to exhibit screw dislocations and two-dimensional nuclei typically observed on inorganic and macromolecular crystals. This presents the first case of non-mineral crystal growth patterns being revealed for a biological organism, which provides an unexpected example of nature exploiting fundamental materials science mechanisms for the morphogenetic control of biological ultrastructures. We have discovered and validated, distinctive formulation-specific high-resolution structural spore coat and dimensional signatures of B. anthracis spores (Sterne strain) grown in different formulation condition. We further demonstrated that measurement of the dimensional characteristics of B. anthracis spores …
Date: March 14, 2011
Creator: Malkin, A J; Elhadj, S & Plomp, M
Object Type: Article
System: The UNT Digital Library
Research, Development and Demonstration of Micro-CHP Systems for Residential Applications - Phase I (open access)

Research, Development and Demonstration of Micro-CHP Systems for Residential Applications - Phase I

The objective of the Micro-CHP Phase I effort was to develop a conceptual design for a Micro-CHP system including: Defining market potential; Assessing proposed technology; Developing a proof-of-principle design; and Developing a commercialization strategy. TIAX LLC assembled a team to develop a Micro-CHP system that will provide electricity and heating. TIAX, the contractor and major cost-share provider, provided proven expertise in project management, prime-mover design and development, appliance development and commercialization, analysis of residential energy loads, technology assessment, and market analysis. Kohler Company, the manufacturing partner, is a highly regarded manufacturer of standby power systems and other residential products. Kohler provides a compellingly strong brand, along with the capabilities in product development, design, manufacture, distribution, sales, support, service, and marketing that only a manufacturer of Kohler's status can provide. GAMA, an association of appliance and equipment manufacturers, provided a critical understanding of appliance commercialization issues, including regulatory requirements, large-scale market acceptance issues, and commercialization strategies. The Propane Education & Research Council, a cost-share partner, provided cost share and aided in ensuring the fuel flexibility of the conceptual design. Micro-CHP systems being commercialized in Europe and Japan are generally designed to follow the household thermal load, and generate electricity opportunistically. In …
Date: March 14, 2011
Creator: Zogg, Robert A.
Object Type: Report
System: The UNT Digital Library
Laser System for Livermore's Mono Energetic Gamma-Ray Source (open access)

Laser System for Livermore's Mono Energetic Gamma-Ray Source

A Mono-energetic Gamma-ray (MEGa-ray) source, based on Compton scattering of a high-intensity laser beam off a highly relativistic electron beam, requires highly specialized laser systems. To minimize the bandwidth of the {gamma}-ray beam, the scattering laser must have minimal bandwidth, but also match the electron beam depth of focus in length. This requires a {approx}1 J, 10 ps, fourier-transform-limited laser system. Also required is a high-brightness electron beam, best provided by a photoinjector. This electron source requires a second laser system with stringent requirements on the beam including flat transverse and longitudinal profiles and fast rise times. Furthermore, these systems must be synchronized to each other with ps-scale accuracy. Using a novel hyper-dispersion compressor configuration and advanced fiber amplifiers and diode-pumped Nd:YAG amplifiers, we have designed laser systems that meet these challenges for the X-band photoinjector and Compton-scattering source being built at Lawrence Livermore National Laboratory.
Date: March 14, 2011
Creator: Gibson, D.; Albert, F.; Bayramian, A.; Marsh, R.; Messerly, M.; Ebbers, C. et al.
Object Type: Article
System: The UNT Digital Library