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USDA Crop Disaster Programs: Lessons Learned Can Improve Implementation of New Crop Assistance Program

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The U.S. Department of Agriculture's (USDA) Farm Service Agency (FSA) provides programs to help farmers recover financially from natural disasters. Congress has historically supplemented these programs with ad hoc programs that pay farmers who experienced crop losses. The 2008 farm bill established a program through 2011 to pay farmers who lose crops. To receive these payments, farmers must purchase cov… more
Date: June 4, 2010
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Novel Sorption Enhanced Reaction Process for Simultaneous Production of CO2 and H2 from Synthesis Gas Produced by Coal Gasification

Description: The goal of this project is to evaluate the extensive feasibility of a novel concept called Thermal Swing Sorption Enhanced Reaction (TSSER) process to simultaneously produce H{sub 2} and CO{sub 2} as a single unit operation in a sorber-reactor. The successful demonstration of the potential feasibility of the TSSER concept implies that it is worth pursuing further development of the idea. This can be done by more extensive evaluation of the basic sorptive properties of the CO{sub 2} chemisorben… more
Date: June 4, 2010
Creator: Sircar, Shivaji; Caram, Hugo S.; Jeong, Kwangkook; Beaver, Michael G.; Ni, Fan & Makebe, Agbor Tabi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High-throughput Accurate-wavelength Lens-based Visible Spectrometera

Description: A scanning visible spectrometer has been prototyped to complement fixed-wavelength transmission grating spectrometers for charge exchange recombination spectroscopy. Fast f/1.8 200 mm commercial lenses are used with a large 2160 mm-1 grating for high throughput. A stepping-motor controlled sine drive positions the grating, which is mounted on a precision rotary table. A high-resolution optical encoder on the grating stage allows the grating angle to be measured with an absolute accuracy of 0.07… more
Date: June 4, 2010
Creator: Bell, Ronald E. & Scoti, Filippo
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Evaluation of Reagent Emplacement Techniques for Phosphate-based Treatment of the Uranium Contamination Source in the 300 Area White Paper

Description: Persistent uranium contamination of groundwater under the 300 Area of the Hanford Site has been observed. The source of the uranium contamination resides in uranium deposits on sediments at the groundwater interface, and the contamination is mobilized when periodically wetted by fluctuations of Columbia River levels. Treatability work is ongoing to develop and apply phosphate-containing reagents to promote the formation of stable and insoluble uranium phosphate minerals (i.e., autunite) and oth… more
Date: June 4, 2010
Creator: Nimmons, Michael J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Telescope Guiding with a HyViSI H2RG Used in Guide Mode

Description: We report on long exposure results obtained with a Teledyne HyViSI H2RG detector operating in guide mode. The sensor simultaneously obtained nearly seeing-limited data while also guiding the Kitt Peak 2.1 m telescope. Results from unguided and guided operation are presented and used to place lower limits on flux/fluence values for accurate centroid measurements. We also report on significant noise reduction obtained in recent laboratory measurements that should further improve guiding capabilit… more
Date: June 4, 2010
Creator: Simms, Lance M.; Figerb, Donald F.; Hanold, Brandon J.; Kahn, Steven M. & Gilmore, D.Kirk
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The science case for 37Ar as a monitor for underground nuclear explosions

Description: A new calculation of the production of 37Ar from nuclear explosion neutron interactions on 40Ca in a suite of common sub-surface materials (rock, etc) is presented. Even in mineral structures that are relatively low in Ca, the resulting 37Ar signature is large enough for detection in cases of venting or gaseous diffusion driven by barometric pumping. Field and laboratory detection strategies and projected sensitivities are presented.
Date: June 4, 2010
Creator: Haas, Derek A.; Orrell, John L.; Bowyer, Ted W.; McIntyre, Justin I.; Miley, Harry S.; Aalseth, Craig E. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Impact of Theoretical Uncertainties in the Halo Mass Function and Halo

Description: We study the impact of theoretical uncertainty in the dark matter halo mass function and halo bias on dark energy constraints from imminent galaxy cluster surveys. We find that for an optical cluster survey like the Dark Energy Survey, the accuracy required on the predicted halo mass function to make it an insignificant source of error on dark energy parameters is {approx}1%. The analogous requirement on the predicted halo bias is less stringent ({approx}5%), particularly if the observable-mass… more
Date: June 4, 2010
Creator: Wu, Hao-Yi; Zentner, Andrew R. & Wechsler, Risa H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Benchmark Specifications and Data Requirements for Initial Modeling of the China Experimental Fast Reactor.

Description: A specification is proposed for an initial transient benchmark analysis of the China Experimental Fast Reactor design based on the analysis capabilities of the SAS4A/SASSYS-1 code. For the initial benchmark, a single-channel protected transient overpower accident is defined. Reactivity feedback coefficients will not be required and simplified material properties are recommended. This report also describes the data required for developing the modeling input. This data includes assembly geometry,… more
Date: June 4, 2010
Creator: Fanning, T. H. & Division, Nuclear Engineering
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Universal versus Material-Dependent Two-Gap Behaviors in the High-Tc Cuprates: Angle-Resolved Photoemission Study of La_2-xSr_xCuO_4

Description: We have investigated the doping and temperature dependences of the pseudogap/superconducting gap in the single-layer cuprate La{sub 2-x}Sr{sub x}CuO{sub 4} by angle-resolved photoemission spectroscopy. The results clearly exhibit two distinct energy and temperature scales, namely, the gap around ({pi}, 0) of magnitude {Delta}{asterisk} and the gap around the node characterized by the d-wave order parameter {delta}{sub 0}, like the double-layer cuprate Bi2212. In comparison with Bi2212 having hi… more
Date: June 4, 2010
Creator: Yoshida, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

On The Origin of Light Dark Matter Species

Description: TeV-mass dark matter charged under a new GeV-scale gauge force can explain electronic cosmic-ray anomalies. We propose that the CoGeNT and DAMA direct detection experiments are observing scattering of light stable states 'GeV-Matter' that are charged under this force and constitute a small fraction of the dark matter halo. Dark higgsinos in a supersymmetric dark sector are natural candidates for GeV-Matter that scatter off protons with a universal cross-section of 5 x 10{sup -38} cm{sup 2} and … more
Date: June 4, 2010
Creator: Essig, Rouven.; Kaplan, Jared.; Schuster, Philip. & Toro, Natalia.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

On Nonlinear Self-interaction of Geodesic Acoustic Mode Driven by Energetic Particles

Description: It is shown that nonlinear self-interaction of energetic particle-driven Geodesic Acoustic Mode does not generate a second harmonic in radial electric field using the fluid model. However, kinetic effects of energetic particles can induce a second harmonic in the radial electric field. A formula for the second order plasma density perturbation is derived. It is shown that a second harmonic of plasma density perturbation is generated by the convective nonlinearity of both thermal plasma and ener… more
Date: June 4, 2010
Creator: Fu, G. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Measurement of Poloidal Velocity on the National Spherical Torus Experiment

Description: A diagnostic suite has been developed to measure impurity poloidal flow using charge exchange recombination spectroscopy on the National Spherical Torus Experiment. Toroidal and poloidal viewing systems measure all quantities required to determine the radial electric field. Two sets of up/down symmetric poloidal views are used to measure both active emission in the plane of the neutral heating beams and background emission in a radial plane away from the neutral beams. Differential velocity mea… more
Date: June 4, 2010
Creator: Bell, Ronald E. & Feder, Russell
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

IceCube: An Instrument for Neutrino Astronomy

Description: Neutrino astronomy beyond the Sun was first imagined in the late 1950s; by the 1970s, it was realized that kilometer-scale neutrino detectors were required. The first such instrument, IceCube, is near completion and taking data. The IceCube project transforms a cubic kilometer of deep and ultra-transparent Antarctic ice into a particle detector. A total of 5,160 optical sensors are embedded into a gigaton of Antarctic ice to detect the Cherenkov light emitted by secondary particles produced whe… more
Date: June 4, 2010
Creator: Collaboration, IceCube; Halzen, F. & Klein, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Strongly Dispersive Transient Bragg Grating for High Harmonics

Description: We create a transient Bragg grating in a high harmonic generation medium using two counterpropagating pulses. The Bragg grating disperses the harmonics in angle and can diffract a large bandwidth with temporal resolution limited only by the source size.
Date: June 4, 2010
Creator: Farrell, J.; Spector, L.S.; /SLAC, PULSE /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept.; Gaarde, M.B.; /SLAC, PULSE /Louisiana State U.; McFarland, B.K. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Two-Bunch Self-Seeding for Narrow-Bandwidth Hard X-Ray Free-Electron Lasers

Description: It is well-known that seeding can be used to produce narrow-bandwidth and fully-coherent x- ray free-electron lasers. Self-seeding, which uses an extra undulator to generate the seed pulse, is perhaps one of the most promising methods to accomplish this. In the hard x-ray regime with high- energy electrons, this method requires a large magnetic chicane to match the path length delay of the x-ray monochromator that selects a narrow bandwidth of radiation. Such a chicane not only takes large foot… more
Date: June 4, 2010
Creator: Ding, Yuantao; Huang, Zhirong & Ruth, Ronald D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Nigeria

Description: This report discusses the political climate, development challenges and reform in Nigeria. The report discusses Nigeria's most recent general elections, which the U.S. State Department called "deeply flawed," were held in April 2007.
Date: June 4, 2010
Creator: Ploch, Lauren
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Federal Chief Technology Officer in the Obama Administration: Options and Issues for Consideration

Description: In November 2007, Senator Barack Obama announced his intention, if elected President, to appoint a federal chief technology officer (CTO). On April 18, 2009, President Obama appointed Virginia Secretary of Technology, Aneesh P. Chopra, to serve as "America's Chief Technology Officer." This report presents President Obama's vision for the CTO position put forth during his campaign for the presidency and during the presidential transition. It also discusses the potential scope of duties and autho… more
Date: June 4, 2010
Creator: Sargent, John F., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Democratic Republic of Congo: Background and Current Developments

Description: This report discusses in brief the current political state of the Democratic Republic of the Congo, as well as the crisis situation in eastern Congo that has displaced more than 250,000 civilians. It also describes U.S., U.N., and other international efforts to aid in resolving the crisis.
Date: June 4, 2010
Creator: Dagne, Ted
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Study of High-Frequency Impedance of Small-Angle Tapers and Collimators

Description: Collimators and transitions in accelerator vacuum chambers often include small-angle tapering to lower the wakefields generated by the beam. While the low-frequency impedance is well described by Yokoya's formula (for axisymmetric geometry), much less is known about the behavior of the impedance in the high frequency limit. In this paper we develop an analytical approach to the highfrequency regime for round collimators and tapers. Our analytical results are compared with computer simulations u… more
Date: June 4, 2010
Creator: Stupakov, Gennady & Podobedov, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Three-Coordinate Terminal Imidoiron(III) Complexes: Structure, Spectroscopy, and Mechanism of Formation

Description: Article discussing three-coordinate terminal imidoiron(III) complexes and the structure, spectroscopy, and the mechanism of formation.
Date: June 4, 2010
Creator: Cowley, Ryan E.; DeYonker, Nathan J.; Eckert, Nathan A.; Cundari, Thomas R., 1964-; DeBeer, Serena 1973-; Bill, E. (Eckhard), 1953- et al.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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