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Development of odd-Z-projectile reactions for transactinide element synthesis

Description: The development of new odd-Z-projectile reactions leading to the production of transactinide elements is described. The cross section of the even-Z-projectile 208Pb(64Ni, n)271Ds reaction was measured at two new energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, seven decay chains attributable to 271Ds were observed. These data, combined with previous results, establish an excitation function for the production of 271Ds. The maximum cross section was 20 +15 -11 pb at a center-of-target energy of 311.5 MeV in the laboratory frame.The data from the 271Ds experiments were used to estimate the optimum beam energy for the new odd-Z-projectile 208Pb(65Cu, n)272-111 reaction using the Fusion by Diffusion theory proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski. A cross section for this reaction was measured for the first time, at a center-of-target energy of 321.1 MeV in the laboratory frame. The excitation energy f or compound nuclei formed at the target center was 13.2 MeV. One decay chain was observed, resulting in a measured cross section of 1.7 +3.9 -1.4 pb. This decay chain is in good agreement with previously published data on the decay of 272-111.The new odd-Z-projectile 208Pb(55Mn, n)262Bh reaction was studied at three different projectile energies, and 33 decay chains of 262Bh were observed. The existence of a previously reported alpha-decaying isomeric state in this nuclide was confirmed. Production of the ground state was preferred at all three beam energies. The maximum cross section was 540 +180 -150 pb at a projectile center-of-target energy of 264.0 MeV. This cross section is much larger than that previously reported for the even-Z-projectile 209Bi(54Cr, n)262Bh reaction, which may be because the 54Cr projectile energies in the latter reaction were too high for optimum production of the 1n product. At the highest projectile energy of 268.0 MeV in ...
Date: November 4, 2004
Creator: Folden III, Charles Marvin
Partner: UNT Libraries Government Documents Department

VUV Spectroscopy in DIII-D Divertor

Description: The research carried out on this grant was motivated by the high power emission from the CIV doublet at 155 nm in the DIII-D divertor and to study the characteristics of the radiative divertor. The radiative divertor is designed to reduce the heat load to the target plates of the divertor by reducing the energy in the divertor plasma using upstream scrape-off-layer (SOL) radiation. In some cases, particularly in Partially Detached Divertor (PDD) operations, this emission accounts for more than 50% of the total radiation from the divertor. In PDD operation, produced by neutral gas injection, the particle flow to the target plate and the divertor temperature are significantly reduced. A father motivation was to study the CIV emission distribution in the lower, open divertor and the upper baffled divertor. Two Vacuum Ultra Violet Tangential viewing Television cameras (VUV TTV) were constructed and installed in the upper, baffled and the lower, open divertor. The images recorded by these cameras were then inverted to produce two-dimensional distributions of CIV in the poloidal plane. Results obtained in the project are summarized in this report.
Date: November 4, 2004
Creator: Punjabi, Alkesh & Jalufka, Nelson
Partner: UNT Libraries Government Documents Department

Digestion of Crystalline Silicotitanate (CST)

Description: Researchers tested methods for chemically dissolving crystalline silicotitanate (CST) as a substitute for mechanical grinding to reduce particle size before vitrification. Testing used the commercially available form of CST, UOP IONSIV(R) IE-911. Reduction of the particle size to a range similar to that of the glass frit used by the Defense Waste Processing Facility (DWPF) could reduce problems with coupling cesium ion exchange to the vitrification process. This study found that IONSIV(R) IE-911 dissolves completely using a combination of acid, hydrogen peroxide, and fluoride ion. Neutralization of the resulting acidic solution precipitates components of the IONSIV(R) IE-911. Digestion requires extremely corrosive conditions. Also, large particles may reform during neutralization, and the initiation and rate of gas generation are unpredictable. Therefore, the method is not recommended as a substitute for mechanical grinding.
Date: November 4, 2004
Creator: DARREL, WALKER
Partner: UNT Libraries Government Documents Department

Present And Near-Term Potential In Applying Weather Information To Improve The Highway System: Position Papers

Description: This document contains positions papers of a policy forum for weather and highways developed by the Atmospheric Policy Program American Meteorological Society in coordination with the Federal Highway Administration (FHWA) with additional support from the National Science Foundation (NSF). In this document (Panel 1), panelists describe proposals to improve the U.S. Highway System with weather information.
Date: November 4, 2004
Creator: Atmospheric Policy Program American Meteorological Society
Partner: UNT Libraries

Controls of Net Ecosystem Exchange at an Old Field, a Pine Plantation, and a Hardwood Forest under Identical Climatic and Edaphic Conditions-Isotopic Studies

Description: During the past year we have submitted two manuscripts. 1. Mortazavi, B., J. Chanton, J.L. Prater, A.C. Oishi, R. Oren and G. Katul. Temporal variability in 13C of respired CO2 in a pine and a hardwood forest subject to similar climatic conditions (in Press). Oecologia 2. Mortazavi, B. and J. P. Chanton. Use of Keeling plots for determining sources of dissolved organic carbon in nearshore and open ocean systems (Published in Limnology and Oceanography (2004) Vol 49 pages 102-108). 3. Mortazavi, B., J. L. Prater, and J. P. Chanton (2004). A field-based method for simultaneous measurements of the 18O and 13C of soil CO2 efflux. Biogeosciences Vol 1:1-16 Most recent products delivered: Mortazavi, B. and J. P. Chanton. Abiotic and biotic controls on the 13C of respired CO2 in the southeastern US forest mosaics and a new technique for measuring the of soil CO2 efflux. Joint Biosphere Stable Isotope Network (US) and Stable Isotopes in Biosphere Atmosphere Exchange (EU) 2004 Meeting, Interlaken, Switzerland, March 31-April 4, 2004. Mortazavi, B., J. Chanton, J.L. Prater, A.C. Oishi, R. Oren and G. Katul. Temporal variability in 13C of respired CO2 in a pine and a hardwood forest subject to similar climatic conditions. American Geophysical Union Fall Meeting, San Francisco, USA, December 8-12, 2003. Prater, J., Mortazavi, B. and J. P. Chanton. Measurement of discrimination against 13C during photosynthesis and quantification of the short-term variability of 13C over a diurnal cycle. American Geophysical Union Fall Meeting, San Francisco, USA, December 8-12, 2003.
Date: November 4, 2004
Creator: Chanton, J. P. & Mortazavi, B.
Partner: UNT Libraries Government Documents Department

Social Security Disability: Improved Processes for Planning and Conducting Demonstrations May Help SSA More Effectively Use Its Demonstration Authority

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Since 1980, the Congress has required the Social Security Administration (SSA) to conduct demonstration projects to test the effectiveness of possible program changes that could encourage individuals to return to work and decrease their dependence on Disability Insurance (DI) benefits. To conduct these demonstrations, the Congress authorized SSA, on a temporary basis, to waive certain DI and Medicare program rules and to use Social Security Trust Funds. The Congress required GAO to review SSA's use of its DI demonstration authority and to make a recommendation as to whether this authority should be made permanent."
Date: November 4, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Highway Safety: Improved Monitoring and Oversight of Traffic Safety Data Program Are Needed

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Auto crashes kill or injure millions of people each year. Information about where and why such crashes occur is important in reducing this toll, both for identifying particular hazards and for planning safety efforts at the state and federal levels. Differences in the quality of state traffic data from state to state, however, affect the usability of data for these purposes. The National Highway Traffic Safety Administration (NHTSA) administers a grant program to help states improve the safety data systems that collect and analyze crash data from police and sheriff's offices and other agencies, and the Congress is considering whether to reauthorize and expand the program. The Senate Appropriations Committee directed GAO to study state systems and the grant program. Accordingly, GAO examined (1) the quality of state crash information, (2) the activities states undertook to improve their traffic records systems and any progress made, and (3) NHTSA's oversight of the grant program."
Date: November 4, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Minijet Deformation and Charge-independent Two-particleCorrelations on Momentum Subspace (eta,phi) In Au-Au Collisions atsqrt(sNN) = 130 GeV

Description: We present first measurements of charge-independent correlations on momentum-space difference variables {eta}{sub 1}-{eta}{sub 2} (pseudorapidity) and {phi}{sub 1}-{phi}{sub 2} (azimuth) for charged primary hadrons with transverse momentum within 0.15 {le} p{sub t} {le} 2 GeV/c and |{eta}| {le} 1.3 from Au-Au collisions at {radical}s{sub NN} = 130 GeV. We observe strong charge-independent correlations associated with minijets and elliptic flow. The width of the minijet peak on {eta}{sub 1}-{eta}{sub 2} increases by a factor 2.3 from peripheral to central collisions, suggesting strong coupling of partons to a longitudinally-expanding colored medium. New methods of jet analysis introduced here reveal nonperturbative medium effects in heavy ion collisions.
Date: November 4, 2004
Creator: Adams, J.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson,B.D.; Arkhipkin, D. et al.
Partner: UNT Libraries Government Documents Department

Meat and Poultry Inspection Issues

Description: This report discusses the responsibility of the U.S. Department of Agriculture’s (USDA’s) Food Safety and Inspection Service (FSIS) for inspecting most meat, poultry, and processed egg products for safety, wholesomeness, and proper labeling.
Date: November 4, 2004
Creator: Becker, Geoffrey S.
Partner: UNT Libraries Government Documents Department

HEAVY QUARK POTENTIALS AND QUARKONIA BINDING.

Description: The author reviews recent progress in studying in-medium modification of inter-quark forces at finite temperature in lattice QCD. Some applications to the problem of quarkonium binding in potential models is also discussed.
Date: November 4, 2004
Creator: PETRECZKY,P.
Partner: UNT Libraries Government Documents Department

The South Pole Telescope

Description: A new 10 meter diameter telescope is being constructed for deployment at the NSF South Pole research station. The telescope is designed for conducting large-area millimeter and sub-millimeter wave surveys of faint, low contrast emission, as required to map primary and secondary anisotropies in the cosmic microwave background. To achieve the required sensitivity and resolution, the telescope design employs an off-axis primary with a 10 m diameter clear aperture. The full aperture and the associated optics will have a combined surface accuracy of better than 20 microns rms to allow precision operation in the submillimeter atmospheric windows. The telescope will be surrounded with a large reflecting ground screen to reduce sensitivity to thermal emission from the ground and local interference. The optics of the telescope will support a square degree field of view at 2mm wavelength and will feed a new 1000-element micro-lithographed planar bolometric array with superconducting transition-edge sensors and frequency-multiplexed readouts. The first key project will be to conduct a survey over 4000 degrees for galaxy clusters using the Sunyaev-Zeldovich Effect. This survey should find many thousands of clusters with a mass selection criteria that is remarkably uniform with redshift. Armed with redshifts obtained from optical and infrared follow-up observations, it is expected that the survey will enable significant constraints to be placed on the equation of state of the dark energy.
Date: November 4, 2004
Creator: Ruhl, J.E.; Ade, P.A.R.; Carlstrom, J.E.; Cho, H.M.; Crawford,T.; Dobbs, M. et al.
Partner: UNT Libraries Government Documents Department

Automobile and Light Truck Fuel Economy: The CAFE Standards

Description: This report discusses energy legislation pertaining to fuel standards. The current corporate average fuel economy standard (CAFE) is 27.5 miles per gallon (mpg) for passenger automobiles and 20.7 mpg for light trucks (scheduled to increase to 22.2 mpg in model year [MY] 2007), a classification that also includes sport utility vehicles (SUVs). Congress had included language in the FY1996-FY2001 Transportation Appropriations prohibiting the use of appropriated funds for any rulemaking on CAFE, effectively freezing the standards.
Date: November 4, 2004
Creator: Bamberger, Robert
Partner: UNT Libraries Government Documents Department

Processing Tritiated Water at the Savannah Rivver Site: A Production Scale Demonstration

Description: The Palladium Membrane Reactor (PMR) process was installed in the Tritium Facilities at the Savannah River Site to perform a production-scale demonstration for the recovery of tritium from tritiated water adsorbed on molecular sieve (zeolite). Unlike the current recovery process that utilizes magnesium, the PMR offers a means to process tritiated water in a more cost effective and environmentally friendly manner. The design and installation of the large-scale PMR process was part of a collaborative effort between the Savannah River Site and Los Alamos National Laboratory. The PMR process operated at the Savannah River Site between May 2001 and April 2003. During the initial phase of operation the PMR processed thirty-four kilograms of tritiated water from the Princeton Plasma Physics Laboratory. The water was processed in fifteen separate batches to yield approximately 34,400 liters (STP) of hydrogen isotopes. Each batch consisted of round-the-clock operations for approximately nine days. In April 2003 the reactor's palladium-silver membrane ruptured resulting in the shutdown of the PMR process. Reactor performance, process performance and operating experiences have been evaluated and documented. A performance comparison between PMR and current magnesium process is also documented.
Date: November 4, 2004
Creator: Sessions, K
Partner: UNT Libraries Government Documents Department

Updates to the ORIGEN-S Cross-Section Libraries Using ENDF-VI, EAF-99, and FENDL-2.0

Description: The standard cross-section library for light-water reactor (LWR) analyses used by the ORIGEN-S depletion and decay code has been extensively updated. This work entailed the development of broad multigroup neutron cross sections for ORIGEN-S from several sources of pointwise continuous-energy cross-section evaluations, including the U.S. Evaluated Nuclear Data Files ENDF/B-VI Release 7, the Fusion Evaluated Nuclear Data Library FENDL-2.0, and the European Activation File EAF-99. The pointwise cross sections were collapsed to a three-group structure using a continuous-energy neutron flux spectrum representative of the typical neutronic conditions of typical LWR fuel and formatted for use by ORIGEN-S. In addition, the fission-product library has been expanded to include ENDF/B-VI fission yield data for 30 fissionable actinides. The processing codes and procedures are explained. Preliminary verification studies using the updated libraries were performed using the modules of the SCALE (Standardized Computer Analyses for Licensing Evaluation) system. Comparisons between the previous basic ORIGEN-S libraries and the updated libraries developed in this work are presented.
Date: November 4, 2004
Creator: Murphy, B.D.
Partner: UNT Libraries Government Documents Department