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PROPOSAL FOR A SILICON VERTEX TRACKER (VTX) FOR THE PHENIX EXPERIMENT.

Description: We propose the construction of a Silicon Vertex Tracker (VTX) for the PHENIX experiment at RHIC. The VTX will substantially enhance the physics capabilities of the PHENIX central arm spectrometers. Our prime motivation is to provide precision measurements of heavy-quark production (charm and beauty) in A+A, p(d)+A, and polarized p+p collisions. These are key measurements for the future RHIC program, both for the heavy ion program as it moves from the discovery phase towards detailed investigati… more
Date: March 30, 2004
Creator: AKIBA,Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Electricity: The Road Toward Restructuring

Description: The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a subs… more
Date: September 30, 2004
Creator: Abel, Amy & Parker, Larry
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analysis of Premixed Charge Compression Ignition Combustion with a Sequential Fluid Mechanics-Multizone Chemical Kinetics Model

Description: We have developed a methodology for analysis of PCCI engines that applies to conditions in which there is some stratification in the air-fuel distribution inside the cylinder at the time of combustion. Our analysis methodology consists of two stages: first, a fluid mechanics code is used to determine temperature and equivalence ratio distributions as a function of crank angle, assuming motored conditions. The distribution information is then used for grouping the mass in the cylinder into a two… more
Date: September 30, 2004
Creator: Aceves, S. M.; Flowers, D. L.; Espinosa-Loza, F.; Babajimopoulos, A. & Assanis, D. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Analysis of Homogeneous Charge Compression Ignition (HCCI) Engines for Cogeneration Applications

Description: This paper presents an evaluation of the applicability of Homogeneous Charge Compression Ignition Engines (HCCI) for small-scale cogeneration (less than 1 MWe) in comparison to five previously analyzed prime movers. The five comparator prime movers include stoichiometric spark-ignited (SI) engines, lean burn SI engines, diesel engines, microturbines and fuel cells. The investigated option, HCCI engines, is a relatively new type of engine that has some fundamental differences with respect to oth… more
Date: April 30, 2004
Creator: Aceves, S; Martinez-Frias, J & Reistad, G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Atmospheric Radiation Measurement Program Science Plan Current Status and Future Directions of the ARM Science Program

Description: The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years t… more
Date: October 30, 2004
Creator: Ackerman, TP; Genio, AD Del; Ellingson, RG; Ferrare, RA; Klein, SA; McFarquhar, GM et al.
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
open access

Fabrication of Mo/Cu Multilayer and Bilayer Transition Edge Sensors

Description: We are developing cryogenic high-resolution x-ray, {gamma}-ray and neutron spectrometers based on superconducting Mo/Cu transition edge sensors. Here we discuss the sensor design for different applications, present the photolithographic fabrication techniques, and outline future detector development to increase spectrometer sensitivity.
Date: September 30, 2004
Creator: Ali, Z. A.; Drury, O. B.; Cunningham, M. F.; Chesser, J. M.; Barbee, T. W., Jr. & Friedrich, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Thermodynamics and Structure of Plutonium Alloys

Description: The goal of this project was to investigate the chemical and structural effects of gallium and impurity elements, iron and nickel, on the phase behavior and crystallography of Pu-Ga alloys. This was done utilizing a theoretical chemical approach to predict binary and ternary alloy energetics, phase stability, and transformations. The modeling results were validated with experimental data derived from the synthesis of selected alloys and advanced characterization tools. The ultimate goal of this… more
Date: January 30, 2004
Creator: Allen, P G; Turchi, P A & Gallegos, G F
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Hydrologic-Geophysical Method for Characterizing Flow and Transport Processes within the Vadose Zone

Description: The research objective of this project is to analyze the resolution of two different geophysical imaging techniques (electrical resistivity tomography and cross-borehole ground penetrating radar) for monitoring subsurface flow and transport processes within the vadose zone. This is being accomplished through a coupled approach involving large scale unsaturated flow modeling, petrophysical conversion of the resulting hydrologic properties to a geophysical property model and generation of synthet… more
Date: June 30, 2004
Creator: Alumbaugh, David L. & Brainard, James R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Extractor Configurations for a Heavy Ion Fusion Volume Source

Description: In order for volume sources to deliver the current (e.g., 0.8 A of Ar{sup +} per module) and brightness necessary for heavy ion fusion (HIF), they must operate at high current density. Conventional extractor designs for 1 to 2 MeV run into voltage breakdown limitations and cannot easily produce the required current rise time (about one microsecond). We discuss two systems that can overcome these volume-extraction problems. Each uses multichannel preaccelerators followed by a single channel main… more
Date: August 30, 2004
Creator: Anderson, O. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Advanced Monitoring to Improve Combustion Turbine/Combined Cycle CT/(CC) Reliability, Availability and Maintainability (RAM)

Description: Power generators are concerned with the maintenance costs associated with the advanced turbines that they are purchasing. Since these machines do not have fully established operation and maintenance (O&M) track records, power generators face financial risk due to uncertain future maintenance costs. This risk is of particular concern, as the electricity industry transitions to a competitive business environment in which unexpected O&M costs cannot be passed through to consumers. These co… more
Date: September 30, 2004
Creator: Angello, Leonard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrogen Storage Properties of Magnesium Base Nanostructured Composite Materials

Description: In this work, nanostructured composite materials have been synthesized using the mechanical alloying process. The new materials produced have been investigated by X-ray diffraction (XRD), transition electron microscope (TEM), scanning electron microscope (SEM) and electron energy dispersion spectrum (EDS) for their phase compositions, crystal structure, grain size, particle morphology and the distribution of catalyst element. Hydrogen storage capacities and the hydriding-dehydriding kinetics of… more
Date: April 30, 2004
Creator: Au, Ming
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Concepts of Model Verification and Validation

Description: Model verification and validation (V&V) is an enabling methodology for the development of computational models that can be used to make engineering predictions with quantified confidence. Model V&V procedures are needed by government and industry to reduce the time, cost, and risk associated with full-scale testing of products, materials, and weapon systems. Quantifying the confidence and predictive accuracy of model calculations provides the decision-maker with the information necessar… more
Date: October 30, 2004
Creator: B.H.Thacker; S.W.Doebling; F.M.Hemez; Anderson, M.C.; Pepin, J.E. & Rodriguez, E.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Gas Turbine Reheat Using In-Situ Combustion

Description: Gas turbine reheat is a well-known technique for increasing the power output of gas turbine, as well as the efficiency in combined cycle operation with higher heat recovery inlet temperatures. The technique also could allow development of an advanced high efficiency turbine with an additional stage, but without a higher inlet temperature. A novel reheat approach, with fuel added via internal passages in turbine airfoils, has been proposed [1]. This avoids the bulky and possible high-NOx discret… more
Date: April 30, 2004
Creator: Bachovchin, D. M. & Lippert, T. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ten Problems in Experimental Mathematics

Description: This article was stimulated by the recent SIAM ''100 DigitChallenge'' of Nick Trefethen, beautifully described in a recent book. Indeed, these ten numeric challenge problems are also listed in a recent book by two of present authors, where they are followed by the ten symbolic/numeric challenge problems that are discussed in this article. Our intent was to present ten problems that are characteristic of the sorts of problems that commonly arise in ''experimental mathematics''. The challenge in … more
Date: September 30, 2004
Creator: Bailey, David H.; Borwein, Jonathan M.; Kapoor, Vishaal & Weisstein, Eric
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Midwest Regional Carbon Sequestration Partnership (MRCSP)

Description: This is the first semiannual report for Phase I of the Midwest Carbon Sequestration Partnership (MRCSP). The project consists of nine tasks to be conducted over a two year period that started in October 2003. The makeup of the MRCSP and objectives are described. Progress on each of the active Tasks is also described and where possible, for those Tasks at some point of completion, a summary of results is presented.
Date: April 30, 2004
Creator: Ball, David; Bradbury, Judith; Lal, Rattan; Wickstrom, Larry; Gupta, Neeraj; Burns, Robert et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effects of Ammonium Molybdophosphate (AMP) on Strontium, Actinides, and RCRA Metals in SRS Simulated Waste

Description: High Level Waste samples contain elevated concentrations of radioactive cesium requiring marked dilution of the waste to facilitate handling in non-shielded facilities. The authors developed a sample treatment protocol, using ammonium molybdophosphate (AMP) to remove sufficient cesium to allow handling of the samples with minimal dilution. The sample treatment protocol includes the following steps: pH adjust the sample to the range of 0.01 to 1.0 M acidity; mix 30 mL of acidified sample with 40… more
Date: April 30, 2004
Creator: Barnes, Mark J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Operation of Solid Oxide Fuel Cell Anodes With Practical Hydrocarbon Fuels

Description: This work was carried out to achieve a better understanding of how SOFC anodes work with real fuels. The motivation was to improve the fuel flexibility of SOFC anodes, thereby allowing simplification and cost reduction of SOFC power plants. The work was based on prior results indicating that Ni-YSZ anode-supported SOFCs can be operated directly on methane and natural gas, while SOFCs with novel anode compositions can work with higher hydrocarbons. While these results were promising, more work w… more
Date: July 30, 2004
Creator: Barnett, Scott A.; Liu, Jiang & Lin, Yuanbo
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Developing State Policies Supportive of Bioenergy Development

Description: Working within the context of the Southern States Biobased Alliance (SSBA) and with officials in each state, the Southern States Energy Board (SSEB) is identifying bioenergy-related policies and programs within each state to determine their impact on the development, deployment or use of bioenergy. In addition, SSEB will determine which policies have impacted industry's efforts to develop, deploy or use biobased technologies or products. As a result, SSEB will work with the Southern States Biob… more
Date: April 30, 2004
Creator: Baskin, Kathryn
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Foreign Intelligence Surveillance Act: Selected Legislation from the 108th Congress

Description: The Foreign Intelligence Surveillance Act, as passed in 1978, provided a statutory framework for the use of electronic surveillance in the context of foreign intelligence gathering. In doing so, Congress sought to strike a balance between national security interests and personal privacy rights. Subsequent legislation expanded federal laws dealing with foreign intelligence gathering to address physical searches, pen registers and trap and trace devices, and access to certain business records.
Date: September 30, 2004
Creator: Bazan, Elizabeth B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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