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Space-charge compensation in high-intensity proton rings

Description: Recently, it was proposed to use negatively charged electron beams for compensation of beam-beam effects due to protons in the Tevatron collider. The authors show that a similar compensation is possible in space-charge dominated low energy proton beams. The idea has a potential of several-fold increase of the FNAL Booster beam brightness. Best results will be obtained using three electron lenses around the machine circumference, using co-moving electron beam with time structure and profile approximately matched to the proton beam. This technique, if feasible, will be more cost effective than the straightforward alternative of increasing the energy of the injection linac.
Date: September 21, 2000
Creator: A. Burov, G.W. Foster and V.D. Shiltsev
Partner: UNT Libraries Government Documents Department


Description: Melter feeds for high-level nuclear waste (HLW) typically contain a large number of constituents that evolve gas on heating, Multiple gas-evolving reactions are both successive and simultaneous, and include the release of chemically bonded water, reactions of nitrates with organics, and reactions of molten salts with solid silica. Consequently, when a sample of a HLW feed is subjected to thermogravimetric analysis (TGA), the rate of change of the sample mass reveals multiple overlapping peaks. In this study, a melter feed, formulated for a simulated high-alumina HLW to be vitrified in the Waste Treatment and Immobilization Plant, currently under construction at the Hanford Site in Washington State, USA, was subjected to TGA. In addition, a modified melter feed was prepared as an all-nitrate version of the baseline feed to test the effect of sucrose addition on the gas-evolving reactions. Activation energies for major reactions were determined using the Kissinger method. The ultimate aim of TGA studies is to obtain a kinetic model of the gas-evolving reactions for use in mathematical modeling of the cold cap as an element of the overall model of the waste-glass melter. In this study, we focused on computing the kinetic parameters of individual reactions without identifying their actual chemistry, The rough provisional model presented is based on the first-order kinetics.
Date: October 21, 2011
Partner: UNT Libraries Government Documents Department

Roles and Delegation of Authority (R/DA) System

Description: The processes of defining managerial roles and providing for delegation of authority are essential to any enterprise. At most large organizations, these processes are defined in policy manuals and through sets of standard operating procedures for many, if not all, business and administrative functions. Many of these staff-initiated, administrative functions require the routing of documents for approval to one or more levels of management. These employee-oriented, back office types of workflows tend to require more flexibility in determining to whom these documents should go to, while, at the same time, providing the responsible parties with the flexibility to delegate their approval authority or allow others to review their work. Although this practice is commonplace in manual, paper-based processes that exist in many organizations, it is difficult to provide the same flexibility in the more structured, electronic-based, workflow systems.
Date: October 21, 1999
Partner: UNT Libraries Government Documents Department

[Fax: Memorandum and News Story]

Description: A fax from the AIDS Services of Dallas to Scott Mackey at the Dallas Voice about an increase in funding for programs that assist persons with HIV/AIDS.
Date: December 21, 1994
Creator: AIDS Services of Dallas
Partner: UNT Libraries Special Collections

Monte Carlo Simulations of Phosphate Polyhedron Connectivity in Glasses

Description: Monte Carlo simulations of phosphate tetrahedron connectivity distributions in alkali and alkaline earth phosphate glasses are reported. By utilizing a discrete bond model, the distribution of next-nearest neighbor connectivities between phosphate polyhedron for random, alternating and clustering bonding scenarios was evaluated as a function of the relative bond energy difference. The simulated distributions are compared to experimentally observed connectivities reported for solid-state two-dimensional exchange and double-quantum NMR experiments of phosphate glasses. These Monte Carlo simulations demonstrate that the polyhedron connectivity is best described by a random distribution in lithium phosphate and calcium phosphate glasses.
Date: December 21, 1999
Creator: ALAM,TODD M.
Partner: UNT Libraries Government Documents Department


Description: The long-term prospects for fully exploring three-flavor mixing in the neutrino sector depend upon an ongoing and increased investment in the appropriate accelerator R&D. Two new concepts have been proposed that would revolutionize neutrino experiments, namely the Neutrino Factory and the Beta Beam facility. These new facilities would dramatically improve our ability to test the three-flavor mixing framework, measure CP violation in the lepton sector, and perhaps determine the neutrino mass hierarchy, and, if necessary, probe extremely small values of the mixing angle {theta}{sub 13}. The stunning sensitivity that could be achieved with a Neutrino Factory is described, together with our present understanding of the corresponding sensitivity that might be achieved with a Beta Beam facility. In the Beta Beam case, additional study is required to better understand the optimum Beta Beam energy, and the achievable sensitivity. Neither a Neutrino Factory nor a Beta Beam facility could be built without significant R&D. An impressive Neutrino Factory R&D effort has been ongoing in the U.S. and elsewhere over the last few years and significant progress has been made towards optimizing the design, developing and testing the required accelerator components, and significantly reducing the cost. The recent progress is described here. There has been no corresponding activity in the U.S. on Beta Beam facility design and, given the very limited resources, there is little prospect of starting a significant U.S. Beta Beam R&D effort in the near future. However, the Beta Beam concept is interesting, and progress on its development in Europe should be followed. The Neutrino Factory R&D program has reached a critical stage in which support is required for two crucial international experiments and a third-generation international design study. If this support is forthcoming, a Neutrino Factory could be added to the Neutrino Community's road map in about a decade.
Date: September 21, 2004
Creator: ALBRIGHT, C.; BERG, J. S.; FERNOW, R.; GALLARDO, J.; KAHN, S.; KIRK, H. et al.
Partner: UNT Libraries Government Documents Department

High-Resolution Transmission Electron Microscopy Calibration of Critical Dimension (CD) Reference Materials

Description: NIST and Sandia have developed a procedure for producing and calibrating critical dimension (CD), or linewidth, reference materials. These reference materials will be used to calibrate metrology instruments used in semiconductor manufacturing. The artifacts, with widths down to 100 nm, are produced in monocrystalline silicon with all feature edges aligned to specific crystal planes. A two-part calibration of these linewidths is used: the primary calibration, with accuracy to within a few lattice plane thicknesses, is accomplished by counting the lattice planes across the sample as-imaged through use of high-resolution transmission electron microscopy (HRTEM). The secondary calibration is the high-precision electrical CD technique. NIST and Sandia are developing critical dimension (CD), or linewidth, reference materials for use by the semiconductor industry. To meet the current requirements of this rapidly changing industry, the widths of the reference features must be at or below the widths of the finest features in production and/or development. Further, these features must produce consistent results no matter which metrology tool (e.g., scanning electron microscope, scanned probe microscope, electrical metrology) is used to make the measurement. This leads to a requirement for the samples to have planar surfaces, known sidewall angles, and uniform material composition. None of the production techniques in use in semiconductor manufacturing can produce features with all these characteristics. In addition, requirements specified in the National Technology Roadmap for Semiconductors indicate that the width of the feature must be accurately calibrated to approximately 1-2 nm, a value well beyond the current capabilities of the instruments used for semiconductor metrology.
Date: September 21, 1999
Partner: UNT Libraries Government Documents Department

Dissolution of low-enriched UO{sub 2}/Al dispersion plates in alkaline peroxide solution.

Description: Some conclusions from this report are: (1) A UO{sub 2}/Al dispersion target can be successfully dissolved in alkaline peroxide solutions; (2) after destruction of the peroxide recovery of the {sup 99}Mo would be nearly identical to existing processes using basic dissolution; (3) a low-enriched UO{sub 2}/Al dispersion targets could potentially be used for the production of {sup 99}Mo; and (4) punched cores from a UO{sub 2}/Al dispersion target will be irradiated to low-level burnup and effects of this LEU target on the recovery of {sup 99}Mo will be investigated. A commercial partner will be sought for full scale demonstrations.
Date: October 21, 1997
Creator: Aase, S.; Conner, C.; Landsberger, S.; Vandegrift, G. F.; Wu, D. & Wygmans, D. G.
Partner: UNT Libraries Government Documents Department

Tests in the variable-density wind tunnel of the NACA 23012 airfoil with plain and split flaps

Description: From Summary: "Section characteristics for use in wing design are presented for the NACA 23012 airfoil with plain and split flaps of 20 percent wing chord at a value of the effective Reynolds number of about 8,000,000. The flap deflections covered a range from 60 degrees upward to 75 degrees downward for the plain flap and from neutral to 90 degrees downward for the split flap. The split flap was aerodynamically superior to the plain flap in producing high maximum lift coefficients and in having lower profile-drag coefficients at high lift coefficients."
Date: January 21, 1938
Creator: Abbott, Ira H. & Greenberg, Harry
Partner: UNT Libraries Government Documents Department

Electric Utility Regulatory Reform: Issues for the 109th Congress

Description: This report discusses regulation issues affecting electricity today. Comprehensive electricity legislation may involve several components: Public Utility Holding Company Act (PUHCA) reform, PURPA's requirement that utilities purchase power from qualifying facilities (QFs), and reliability.
Date: April 21, 2005
Creator: Abel, Amy
Partner: UNT Libraries Government Documents Department

[RE: Outline of Valsin Marmillion's Public Relations Speech Given At April 28, 1989 Meeting, Sarasota, Florida]

Description: A memo from Julie Able, program associate, Getty Center for Education in the Arts, to the Regional Institute Directors. The memo is in regards to an attached outline of Valsin Marmillion's public relations speech, that was accidentally left out of the notes from the April 28, 1989 director's meeting.
Date: August 21, 1989
Creator: Abel, Julie
Partner: UNT Libraries Special Collections

[RE: Phase II Regional Institute Directors' Travel Fund]

Description: Photocopy of a letter from Julie Abel, Program Associate, Getty Center for Education in the Arts, to RIG Directors. The letter is in regards to the FY96 RIG Travel Fund and how the directors should take advantage of it for this fiscal year as the Center may not budget for it next year. The Center will be accepting proposals at any time until April 1, 1996 for travel prior to July 31, 1996.
Date: September 21, 1995
Creator: Abel, Julie
Partner: UNT Libraries Special Collections

[RE: RIG Brochures for FY96 Center Exhibits]

Description: Photocopy of a letter from Julie Able, Program Associate, Getty Center for Education in the Arts, to the Regional Institute Directors saying that the Center will no longer be exhibiting at the November 1 - 4, 1995 convention of the National Middle School Association. Therefore the directors brochures will no longer be necessary for distribution until February 1996.
Date: September 21, 1995
Creator: Abel, Julie
Partner: UNT Libraries Special Collections

Drying Results of K-Basin Damaged/Corroded SNF Internal Sludge and Surface Coating

Description: Experiments were performed using a thermogravimetric analysis (TGA) system by Pacific Northwest National Laboratory (PNNL)to study the drying behavior of the K-Basin spent nuclear fuel (SNF) internal sludge and two different surface coatings of SNF elements. These measurements were conducted in support of the safety and process analyses of the proposed Integrated Process Strategy (IPS) to move the N-Reactor fuel stored at K-Basin to an interim storage facility. These limited experiments on the corrosion products of K-Basin SNF material were part of the broad studies performed to ascertain the bounding pressurization of the Multi-Canister Overpack (MCO). Seven SNF internal sludge samples taken from different damage regions of three damaged/corroded outer K-Basin SNF elements were dried. Additionally, two surface coating samples taken from two SNF elements stored at K-West were tested. All the tests were performed in a vacuum atmosphere with the same temperature ramp rate of about 0.4 C/ min. Each TGA test sample was weighed before and after the test on a balance located in the Shielded Analytical Laboratory hot cell. The test samples were vacuum dried in the TGA system for about 24 hours prior to heating them at the rate of 0.4 C/min. The observations from the weight change data are summarized below.
Date: September 21, 2000
Creator: Abrefah, J.; Alexander, D.L. & Marschman, S.C.
Partner: UNT Libraries Government Documents Department