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Accelerating scientific discovery : 2007 annual report. (open access)

Accelerating scientific discovery : 2007 annual report.

As a gateway for scientific discovery, the Argonne Leadership Computing Facility (ALCF) works hand in hand with the world's best computational scientists to advance research in a diverse span of scientific domains, ranging from chemistry, applied mathematics, and materials science to engineering physics and life sciences. Sponsored by the U.S. Department of Energy's (DOE) Office of Science, researchers are using the IBM Blue Gene/L supercomputer at the ALCF to study and explore key scientific problems that underlie important challenges facing our society. For instance, a research team at the University of California-San Diego/ SDSC is studying the molecular basis of Parkinson's disease. The researchers plan to use the knowledge they gain to discover new drugs to treat the disease and to identify risk factors for other diseases that are equally prevalent. Likewise, scientists from Pratt & Whitney are using the Blue Gene to understand the complex processes within aircraft engines. Expanding our understanding of jet engine combustors is the secret to improved fuel efficiency and reduced emissions. Lessons learned from the scientific simulations of jet engine combustors have already led Pratt & Whitney to newer designs with unprecedented reductions in emissions, noise, and cost of ownership. ALCF staff members provide …
Date: November 14, 2008
Creator: Beckman, P.; Dave, P. & Drugan, C.
Object Type: Report
System: The UNT Digital Library
Accessing tri-gluon correlations in the nucleon via the singlespin asymmetry in open charm production (open access)

Accessing tri-gluon correlations in the nucleon via the singlespin asymmetry in open charm production

We calculate the single transverse-spin asymmetry for open charm production in pp collisions within the QCD collinear factorization approach. We include contributions from both twist-three quark-gluon and tri-gluon correlation functions. We find that the quark-gluon correlation functions alone generate only a very small asymmetry for open charm production in the kinematic region of current interest at RHIC, so that the observation of any significant single-spin asymmetry would be a clear indication of the presence of tri-gluon correlations inside a polarized proton. We furthermore demonstrate that the tri-gluon contribution could be very different for the production of D and \bar{D} mesons. These features make the single spin asymmetry in open charm production in polarized pp collisions at RHIC an excellent probe of tri-gluon correlation functions.
Date: November 14, 2008
Creator: Kang, Zhong-Bo; Qiu, Jian-Wei; Vogelsang, Werner & Yuan, Feng
Object Type: Article
System: The UNT Digital Library
Active Damping of the E-P Instability at the LANL PSR (open access)

Active Damping of the E-P Instability at the LANL PSR

A prototype of an analog, transverse (vertical) feedback system for active damping of the two-stream (e-p) instability has been developed and successfully tested at the Los Alamos National Laboratory Proton Storage Ring (PSR). This system was able to improve the instability threshold by approximately 30% (as measured by the change in RF buncher voltage at instability threshold). Evidence obtained from these tests suggests that further improvement in performance is limited by beam leakage into the gap at lower RF buncher voltage and the onset of instability in the horizontal plane, which had no feedback. Here we describe the present system configuration, system optimization, results of several recent experimental tests, and results from studies of factors limiting its performance.
Date: November 14, 2007
Creator: McCrady, R.; Macek, R.J.; Zaugg, T.; Alamos, /Los; Assadi, S.; Deibele, C. et al.
Object Type: Article
System: The UNT Digital Library
Addition of Tropospheric Chemistry and Aerosols to the NCAR Community Climate System Model (open access)

Addition of Tropospheric Chemistry and Aerosols to the NCAR Community Climate System Model

Atmospheric chemistry and aerosols have several important roles in climate change. They affect the Earth's radiative balance directly: cooling the earth by scattering sunlight (aerosols) and warming the Earth by trapping the Earth's thermal radiation (methane, ozone, nitrous oxide, and CFCs are greenhouse gases). Atmospheric chemistry and aerosols also impact many other parts of the climate system: modifying cloud properties (aerosols can be cloud condensation nuclei), fertilizing the biosphere (nitrogen species and soil dust), and damaging the biosphere (acid rain and ozone damage). In order to understand and quantify the effects of atmospheric chemistry and aerosols on the climate and the biosphere in the future, it is necessary to incorporate atmospheric chemistry and aerosols into state-of-the-art climate system models. We have taken several important strides down that path. Working with the latest NCAR Community Climate System Model (CCSM), we have incorporated a state-of-the-art atmospheric chemistry model to simulate tropospheric ozone. Ozone is not just a greenhouse gas, it damages biological systems including lungs, tires, and crops. Ozone chemistry is also central to the oxidizing power of the atmosphere, which destroys a lot of pollutants in the atmosphere (which is a good thing). We have also implemented a fast chemical mechanism …
Date: November 14, 2005
Creator: Cameron-Smith, P.; Lamarque, J.; Connell, P.; Chuang, C.; Rotman, D. & Taylor, J.
Object Type: Report
System: The UNT Digital Library
Advanced diffusion studies with isotopically controlled materials (open access)

Advanced diffusion studies with isotopically controlled materials

The use of enriched stable isotopes combined with modern epitaxial deposition and depth profiling techniques enables the preparation of material heterostructures, highly appropriate for self- and foreign-atom diffusion experiments. Over the past decade we have performed diffusion studies with isotopically enriched elemental and compound semiconductors. In the present paper we highlight our recent results and demonstrate that the use of isotopically enriched materials ushered in a new era in the study of diffusion in solids which yields greater insight into the properties of native defects and their roles in diffusion. Our approach of studying atomic diffusion is not limited to semiconductors and can be applied also to other material systems. Current areas of our research concern the diffusion in the silicon-germanium alloys and glassy materials such as silicon dioxide and ion conducting silicate glasses.
Date: November 14, 2004
Creator: Bracht, Hartmut A.; Silvestri, Hughes H. & Haller, Eugene E.
Object Type: Article
System: The UNT Digital Library
Afghanistan: Government Formation and Performance (open access)

Afghanistan: Government Formation and Performance

This report discusses the current political state of Afghanistan, as well as the Afghan government. This report also discusses Afghanistan's relationship with the United States, particularly U.S. efforts to urge President Hamid Karzai to address corruption within the Afghan government.
Date: November 14, 2008
Creator: Katzman, Kenneth
Object Type: Report
System: The UNT Digital Library
AGN-Induced Cavities in NGC 1399 And NGC 4649 (open access)

AGN-Induced Cavities in NGC 1399 And NGC 4649

We present an analysis of archival Chandra and VLA observations of the E0 galaxy NGC1399 and the E2 galaxy NGC4649 in which we investigate cavities in the surrounding X-ray emitting medium caused by the central AGN. We calculate the jet power required for the AGN to evacuate these cavities and find values of {approx} 8x10{sup 41} erg s-1 and {approx} 14x10{sup 41} erg s{sup -1} for the lobes of NGC1399 and {approx} 7x10{sup 41} erg s{sup -1} and {approx} 6x1041 erg s{sup -1} for those of NGC4649. We also calculate the k/f values for each cavity, where k is the ratio of the total particle energy to that of electrons radiating in the range of 10 MHz to 10 GHz, and f is the volume filling factor of the plasma in the cavity. We find that the values of k/f for the lobes of NGC1399 are {approx} 93 and {approx} 190, and those of the lobes of NGC4649 are {approx} 15000 and {approx} 12000. We conclude that the assumed spectrum describes the electron distribution in the lobes of NGC1399 reasonably well, and that there are few entrained particles. For NGC4649, either there are many entrained particles or the model spectrum …
Date: November 14, 2007
Creator: Shurkin, K.; U., /New Mexico; Dunn, R. J. H.; U., /Southampton; Gentile, G.; Taylor, G. B. et al.
Object Type: Article
System: The UNT Digital Library

Air Cooling Technology for Power Electronics Thermal Control

Assessing potential for air cooling in power electronics is a critical factor in power electronics equipment. NREL aims to assess effective air cooling techniques for power electronics technologies.
Date: November 14, 2007
Creator: Bharathan, D.
Object Type: Presentation
System: The UNT Digital Library
Air Force presentation of methodology on original DoD recommendations - Cap Hill - 5/17/05 (open access)

Air Force presentation of methodology on original DoD recommendations - Cap Hill - 5/17/05

US Air Force presentation of recommendation and methodology of original DoD Secretary of Defense recommendations for closure and realignment(5/12/05). Includes questions from Commissioners to Witnesses.
Date: November 14, 2005
Creator: United States. Defense Base Closure and Realignment Commission.
Object Type: Text
System: The UNT Digital Library
Alternative Fuel News, Volume 4, Number 3 (open access)

Alternative Fuel News, Volume 4, Number 3

This issue of Alternative Fuel News focuses on transit buses and refuse haulers. Many transit agencies and waste management companies are investigating alternatives to traditional diesel buses and refuse haulers.
Date: November 14, 2000
Creator: Ficker, C.
Object Type: Book
System: The UNT Digital Library
Amtrak: Budget and Reauthorization (open access)

Amtrak: Budget and Reauthorization

This report is on Amtrak: Budget and Reauthorization.
Date: November 14, 2007
Creator: Frittelli, John & Peterman, David Randall
Object Type: Report
System: The UNT Digital Library
Analysis of Cost-Effective Off-Board Hydrogen Storage and Refueling Stations (open access)

Analysis of Cost-Effective Off-Board Hydrogen Storage and Refueling Stations

This report highlights design and component selection considerations for compressed gas hydrogen fueling stations operating at 5000 psig or 350 bar. The primary focus is on options for compression and storage – in terms of practical equipment options as well as various system configurations and how they influence delivery performance and station economics.
Date: November 14, 2008
Creator: Barnes, Ted & Liss, William
Object Type: Report
System: The UNT Digital Library
Apalachicola-Chattahoochee-Flint (ACF) Drought: Federal Reservoir and Species Management (open access)

Apalachicola-Chattahoochee-Flint (ACF) Drought: Federal Reservoir and Species Management

This report describes the Federal Reservoir and Species Management of Apalachicola-Chattahoochee-Flint (ACF) Drought.
Date: November 14, 2007
Creator: Carter, Nicole T.; Corn, M. Lynne; Abel, Amy; Kaplan, Stan Mark; Buck, Eugene H.; Folger, Peter et al.
Object Type: Report
System: The UNT Digital Library
Applying Agreed-Upon Procedures: Federal Unemployment Taxes (open access)

Applying Agreed-Upon Procedures: Federal Unemployment Taxes

Correspondence issued by the General Accounting Office with an abstract that begins "We have performed the procedures contained in the enclosure to this report, which we agreed to perform, solely to assist the Department of Labor in ascertaining whether the net federal unemployment tax (FUTA) revenue distributed to the Unemployment Trust Fund (UTF) for the fiscal year ended September 30, 2003, is supported by the underlying records. As agreed with the Inspector General, we evaluated fiscal year 2003 activity affecting distributions to the UTF."
Date: November 14, 2003
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Argonne's contribution to regional development : successful examples. (open access)

Argonne's contribution to regional development : successful examples.

Argonne National Laboratory's mission is basic research and technology development to meet national goals in scientific leadership, energy technology, and environmental quality. In addition to its core missions as a national research and development center, Argonne has exerted a positive impact on its regional economic development, has carried out outstanding educational programs not only for college/graduate students but also for pre-college students and teachers, and has fostered partnerships with universities for research collaboration and with industry for shaping the new technological frontiers.
Date: November 14, 2000
Creator: Chang, Y. I.
Object Type: Article
System: The UNT Digital Library
Armenia-Azerbaijan Conflict (open access)

Armenia-Azerbaijan Conflict

This report presents an overview of the Armenia-Azerbaijan conflict. This is a clash between the principles of territorial integrity and self-determination that is occurring in the Caucasus, creating the longest inter-ethnic dispute in the former Soviet Union. The report includes the background and analysis of history, warfare and peace process in the region. The report discusses the Armenian and Azerbaijani perspective, the role and views of others (Iran, Turkey, Russia), as well as the U.S. policy regarding the conflict.
Date: November 14, 2002
Creator: Migdalovitz, Carol
Object Type: Report
System: The UNT Digital Library
Army Aviation: The RAH-66 Comanche Helicopter Issue (open access)

Army Aviation: The RAH-66 Comanche Helicopter Issue

Although it has been a high priority Army program, a number of factors have complicated the RAH-66 Comanche program. Since its inception, the program has been restructured several times–postponing the initial operational capability (IOC) and increasing overall program costs. Presently, there is debate within the Army regarding whether the program should be reduced significantly to make funds available to pursue other modernization priorities.
Date: November 14, 2002
Creator: Bolkcom, Christopher
Object Type: Report
System: The UNT Digital Library
Atomic Scale coexistence of Periodic and quasiperiodic order in a2-fold A1-Ni-Co decagonal quasicrystal surface (open access)

Atomic Scale coexistence of Periodic and quasiperiodic order in a2-fold A1-Ni-Co decagonal quasicrystal surface

Decagonal quasicrystals are made of pairs of atomic planes with pentagonal symmetry periodically stacked along a 10-fold axis. We have investigated the atomic structure of the 2-fold surface of a decagonal Al-Ni-Co quasicrystal using scanning tunneling microscopy (STM). The surface consists of terraces separated by steps of heights 1.9, 4.7, 7.8, and 12.6{angstrom} containing rows of atoms parallel to the 10-fold direction with an internal periodicity of 4{angstrom}. The rows are arranged aperiodically, with separations that follow a Fibonacci sequence and inflation symmetry. The results indicate that the surfaces are preferentially Al-terminated and in general agreement with bulk models.
Date: November 14, 2005
Creator: Park, Jeong Young; Ogletree, D. F.; Salmeron, M.; Ribeiro, R. A.; Canfield, P. C.; Jenks, C. J. et al.
Object Type: Article
System: The UNT Digital Library
Bankruptcy Relief and Natural Disaster Victims (open access)

Bankruptcy Relief and Natural Disaster Victims

This report considers whether bankruptcy law in general, and the BAPCPA in particular, may present unique challenges to financial recovery for those whose life, livelihood, and/or home have been damaged or destroyed.
Date: November 14, 2005
Creator: Jeweler, Robin
Object Type: Report
System: The UNT Digital Library
Benefits for the Aged and the Federal Budget: Short- and Long-Term Projections (open access)

Benefits for the Aged and the Federal Budget: Short- and Long-Term Projections

As the 108th Congress addresses short-term budget decisions, it may also want to consider the long-run impacts of those decisions and the major shifts in budget composition that are underway. Congress may be pressed to add new benefits in response to population aging, such as improved support for long-term care and broader Medicare drug coverage.
Date: November 14, 2002
Creator: Storey, James R.
Object Type: Report
System: The UNT Digital Library
Biological Treatment of Petroleum in Radiologically Contaminated Soil (open access)

Biological Treatment of Petroleum in Radiologically Contaminated Soil

This chapter describes ex situ bioremediation of the petroleum portion of radiologically co-contaminated soils using microorganisms isolated from a waste site and innovative bioreactor technology. Microorganisms first isolated and screened in the laboratory for bioremediation of petroleum were eventually used to treat soils in a bioreactor. The bioreactor treated soils contaminated with over 20,000 mg/kg total petroleum hydrocarbon and reduced the levels to less than 100 mg/kg in 22 months. After treatment, the soils were permanently disposed as low-level radiological waste. The petroleum and radiologically contaminated soil (PRCS) bioreactor operated using bioventing to control the supply of oxygen (air) to the soil being treated. The system treated 3.67 tons of PCRS amended with weathered compost, ammonium nitrate, fertilizer, and water. In addition, a consortium of microbes (patent pending) isolated at the Savannah River National Laboratory from a petroleum-contaminated site was added to the PRCS system. During operation, degradation of petroleum waste was accounted for through monitoring of carbon dioxide levels in the system effluent. The project demonstrated that co-contaminated soils could be successfully treated through bioventing and bioaugmentation to remove petroleum contamination to levels below 100 mg/kg while protecting workers and the environment from radiological contamination.
Date: November 14, 2005
Creator: BERRY, CHRISTOPHER
Object Type: Book
System: The UNT Digital Library
Bolivia: Political and Economic Developments and Relations with the United States (open access)

Bolivia: Political and Economic Developments and Relations with the United States

This report includes background information on Bolivia's political unrest, particularly regarding instability in shifting leaderships, economic situation, and relations with the United States.
Date: November 14, 2008
Creator: Seelke, Clare Ribando
Object Type: Report
System: The UNT Digital Library
Bosnia: Overview of Issues Ten Years After Dayton (open access)

Bosnia: Overview of Issues Ten Years After Dayton

On November 21-22, 2005, the United States will host a meeting with Bosnia’s collective leadership to commemorate the 10th anniversary of the Dayton accords, an agreement brokered under U.S. leadership that ended the 1992-1995 conflict in Bosnia- Herzegovina. Since early 2005, the Bush Administration has given renewed emphasis to “unfinished business” in the western Balkan region, such as the unresolved status of Kosovo, a U.N.-run province of Serbia. The United States also seeks to bolster Bosnia’s further development as a unified, democratic, and stable state on the path toward Euro- Atlantic integration, including major constitutional reforms. This report provides an overview of prominent current issues concerning Bosnia and will be updated after the 10th anniversary meeting in Washington.
Date: November 14, 2005
Creator: Kim, Julie
Object Type: Report
System: The UNT Digital Library
The Budget for Fiscal Year 2002 (open access)

The Budget for Fiscal Year 2002

The report is categorized into seven categories: (I) Background and Analysis, (II) Budget Totals, (III) Budget Action, (IV) Outlays, (V) Receipts, (VI) Surpluses or Deficits, and (VII) The Budget and The Economy.
Date: November 14, 2002
Creator: Winters, Philip D.
Object Type: Report
System: The UNT Digital Library