Cometary X-ray emission: theoretical cross sections following charge exchange by multiply charged ions of astrophysical interest (open access)

Cometary X-ray emission: theoretical cross sections following charge exchange by multiply charged ions of astrophysical interest

The CTMC method is used to calculate emission cross sections following charge exchange collisions involving highly charged ions of astrophysical interest and typical cometary targets. Comparison is made to experimental data obtained on the EBIT machine at Lawrence Livermore National Laboratory (LLNL) for O{sup 8+} projectiles impinging on different targets at a collision energy of 10 eV/amu. The theoretical cross sections are used together with ion abundances measured by the Advanced Composition Explorer as well as those obtained by a fitting procedure using laboratory emission cross sections in order to reproduce the x-ray spectrum of comet C/LINEAR S4 measured on July 14th 2001.
Date: February 13, 2007
Creator: Otranto, S; Olson, R E & Beiersdorfer, P
Object Type: Article
System: The UNT Digital Library
Morphological tranformation of calcite crystal growth by prismatic "acidic" polypeptide sequences. (open access)

Morphological tranformation of calcite crystal growth by prismatic "acidic" polypeptide sequences.

Many of the interesting mechanical and materials properties of the mollusk shell are thought to stem from the prismatic calcite crystal assemblies within this composite structure. It is now evident that proteins play a major role in the formation of these assemblies. Recently, a superfamily of 7 conserved prismatic layer-specific mollusk shell proteins, Asprich, were sequenced, and the 42 AA C-terminal sequence region of this protein superfamily was found to introduce surface voids or porosities on calcite crystals in vitro. Using AFM imaging techniques, we further investigate the effect that this 42 AA domain (Fragment-2) and its constituent subdomains, DEAD-17 and Acidic-2, have on the morphology and growth kinetics of calcite dislocation hillocks. We find that Fragment-2 adsorbs on terrace surfaces and pins acute steps, accelerates then decelerates the growth of obtuse steps, forms clusters and voids on terrace surfaces, and transforms calcite hillock morphology from a rhombohedral form to a rounded one. These results mirror yet are distinct from some of the earlier findings obtained for nacreous polypeptides. The subdomains Acidic-2 and DEAD-17 were found to accelerate then decelerate obtuse steps and induce oval rather than rounded hillock morphologies. Unlike DEAD-17, Acidic-2 does form clusters on terrace surfaces and …
Date: February 13, 2007
Creator: Kim, I; Giocondi, J L; Orme, C A; Collino, J & Evans, J S
Object Type: Article
System: The UNT Digital Library
The Nevada Test Site as a Lunar Analog Test Area (open access)

The Nevada Test Site as a Lunar Analog Test Area

The Nevada Test Site (NTS) is a large (1,350 square miles) secure site currently operated by National Security Technologies, LLC (NSTec), for the U.S. Department of Energy and was established in 1951 to provide a venue for testing nuclear weapons. Three areas with a variety of elevation and geological parameters were used for testing, but the largest number of tests was in Yucca Flat. The Yucca Flat area is approximately 5 miles wide and 20 miles long and approximately 460 subsidence craters resulted from testing in this area. The Sedan crater displaced approximately 12 million tons of earth and is the largest of these craters at 1,280 feet across and 320 feet deep. The profiles of Sedan and the other craters offer a wide variety of shapes and depths that are ideally suited for lunar analog testing.
Date: February 13, 2007
Creator: Freid, Sheldon
Object Type: Article
System: The UNT Digital Library
POINT 2007: A Temperature Dependent ENDF/.B-VII.0 Data Cross Section Library (open access)

POINT 2007: A Temperature Dependent ENDF/.B-VII.0 Data Cross Section Library

This report is one in the series of ''POINT'' reports that over the years have presented temperature dependent cross sections for the then current version of ENDF/B. In each case I have used publicly available nuclear data (the current ENDF/B data, available online at the National Nuclear Data Center, Brookhaven National Laboratory http://www.nndc.bnl.gov/) and publicly available computer codes (the current PREPRO codes, available on-line at the Nuclear Data Section, IAEA, Vienna, Austria http://wwwnds. iaea.or.at/ndspub/endf/prepro/). I have used these in combination to produce the temperature dependent cross sections used in applications and presented in this report. The preceding POINT 2004 report [R1] presented results for the now frozen last version of ENDF/B-VI, Release 8. The current POINT 2007 report is based on data from recently released ENDF/B-VII.0, which is the first release of ENDF/B-VII.
Date: February 13, 2007
Creator: Cullen, D E
Object Type: Report
System: The UNT Digital Library
FY06 LDRD Final Report Data Intensive Computing (open access)

FY06 LDRD Final Report Data Intensive Computing

The goal of the data intensive LDRD was to investigate the fundamental research issues underlying the application of High Performance Computing (HPC) resources to the challenges of data intensive computing. We explored these issues through four targeted case studies derived from growing LLNL programs: high speed text processing, massive semantic graph analysis, streaming image feature extraction, and processing of streaming sensor data. The ultimate goal of this analysis was to provide scalable data management algorithms to support the development of a predictive knowledge capability consistent with the direction of Aurora.
Date: February 13, 2007
Creator: Abdulla, G M
Object Type: Report
System: The UNT Digital Library
FLAMMABILITY AND CONSEQUENCE ANALYSIS FOR MCU WASTE TANKS (open access)

FLAMMABILITY AND CONSEQUENCE ANALYSIS FOR MCU WASTE TANKS

The Savannah River Site of Department of Energy will use the new Modular Caustic Side Solvent Extraction Unit (MCU) to process the waste stream by removing/reducing Cs-137 using Caustic Side Solvent Extraction (CSSX) technology. The CSSX technology utilizes multicomponent organic solvent and annular centrifugal contactors to extract Cs-137 from waste salt solution. Due to the radiolysis of the aqueous nuclear wastes, hydrogen generation is expected in the MCU holding tanks. The hydrogen from radiolysis and the vapor from the organic component of the solvent, Isopar-L, may form a composite flammable gas mixture, resulting in a shorter time to flammability than that of a pure hydrogen environment. It has been found that the time-to-Lower Flammability Limit (LFL) and stoichiometric concentration (SC) vary greatly from tank to tank, and could be decreased significantly by the presence of the Isopar-L. However, neither the deflagration nor the detonation event would challenge the Evaluation Guideline for any of the tanks at any liquid level.
Date: February 13, 2007
Creator: Knight, J & Mukesh Gupta, M
Object Type: Article
System: The UNT Digital Library
LQCD Phase 1 Runs with P4RHMC (open access)

LQCD Phase 1 Runs with P4RHMC

These results represent the first set of runs of 10 {beta} values ranging from 2000-7000 trajectories with the p4rhmc code. This initial run sequence spanned roughly 2-weeks in late January and Early February, 2007. To manage the submission of dependent jobs: subSet.pl--submits a set of dependent jobs for a single run; rmSet.pl--removes a set of dependent jobs in reverse order of submission; and statSet.pl--runs pstat command and prints parsed output along with directory contents. The results of running the statSet.pl command are printed for three different times during the start up the next sequence of runs using the milc code.
Date: February 13, 2007
Creator: Soltz, R. & Gupta, R.
Object Type: Report
System: The UNT Digital Library
Three Blind Men and the Elephant (open access)

Three Blind Men and the Elephant

Just like the blind men in the popular story of perceiving the elephant, the three major constituencies participating in the energy debate have greatly different perceptions of the problem. The constituency that is worried about climate change believes the energy problem is caused by profligate use of fossil fuel that has dramatically changed our atmosphere. The energy security group sees dangerous reliance on foreign sources of oil increasingly held by countries hostile to the US. The economic vitality group sees high energy prices and their effect on the economy and our life-style. Just like the blind men, each of the three constituencies perceives a different problem. And just as with the blind men, while each perspective is right as a piece of the elephant, it takes all the perspectives together to actually solve the problem. Environmentalists focus on solutions responding to the scientific consensus that greenhouse gases are creating rapid climate change. The tipping point has come: it is now a consensus position among scientists the global warming is being affected by anthropogenic activity to 90% certainty according to the last IPCC report. Although they still struggle with the prediction of how much global temperatures will rise if we do …
Date: February 13, 2007
Creator: Long, J S
Object Type: Article
System: The UNT Digital Library
Simulator for the Linear Collider (SLIC): a Tool for ILC Detector Simulations (open access)

Simulator for the Linear Collider (SLIC): a Tool for ILC Detector Simulations

The Simulator for the Linear Collider (SLIC) is a detector simulation program based on the GEANT4 toolkit. It is intended to enable end users to easily model detector concepts by providing the ability to fully describe detectors using plain text files read in by a common executable at runtime. The detector geometry, typically the most complex part of a detector simulation, is described at runtime using the Linear Collider Detector Description (LCDD). This system allows end users to create complex detector geometries in a standard XML format rather than procedural code such as C++. The LCDD system is based on the Geometry Description Markup Language (GDML) from the LHC Applications Group (LCG). The geometry system facilitates the study of different full detector design and their variations. SLIC uses the StdHep format to read input created by event generators and outputs events in the Linear Collider IO (LCIO) format. The SLIC package provides a binding to GEANT4 and many additional commands and features for the end user.
Date: February 13, 2007
Creator: Graf, N. & McCormick, J.
Object Type: Article
System: The UNT Digital Library
6H-SiC Photoconductive Switches Triggered at Below Bandgap Wavelengths (open access)

6H-SiC Photoconductive Switches Triggered at Below Bandgap Wavelengths

Semi-insulating silicon carbide (SiC) is an attractive material for application as high voltage, photoconductive semiconductor switches (PCSS) due to its large bandgap, high critical electric field strength, high electron saturation velocity and high thermal conductivity. The critical field strength of 300 MV/m for 6H-SiC makes it particularly attractive for compact, high voltage, fast switching applications. To realize the benefits of the high bulk electric field strength of SiC and diffuse switch current, carriers must be excited throughout the bulk of the photo switch. Photoconducting switches with opposing electrodes were fabricated on ''a'' plane, vanadium compensated, semiinsulating, 6H-SiC substrates. The PCSS devices were switched by optically exciting deep extrinsic levels lying within the 6H-SiC bandgap. The SiC photoswitches were tested up to a bias voltage of 11000 V with a corresponding peak current of 150 A. The 6H-SiC substrates withstood average electric fields up to 27 MV/m. Minimum PCCS dynamic resistances of 2 and 10 {Omega} were obtained with 13 mJ optical pulses at 532 and 1064 nm wavelengths, respectively.
Date: February 13, 2007
Creator: Sullivan, J S & Stanley, J R
Object Type: Article
System: The UNT Digital Library
Intelligent Detector Design (open access)

Intelligent Detector Design

At a future e+e- linear collider, precision measurements of jets will be required in order to understand physics at and beyond the electroweak scale. Calorimetry will be used with other detectors in an optimal way to reconstruct particle 4-vectors with unprecedented precision. This Particle Flow Algorithm (PFA) approach is seen as the best way to achieve particle mass resolutions from dijet measurements in the range of {approx} 30%/{radical}E, resulting in innovative methods for choosing the calorimeter technology and optimizing the detector design.
Date: February 13, 2007
Creator: Graf, N.; Cassell, R.; Johnson, T.; McCormick, J.; Magill, S. & Kuhlmann, S.
Object Type: Article
System: The UNT Digital Library
Measurement and Improved Understanding of Vertical Transport and the Evaluation of these Processes in Mesoscale Models (open access)

Measurement and Improved Understanding of Vertical Transport and the Evaluation of these Processes in Mesoscale Models

The NCAR effort is primarily focused on the analysis of a diverse suite of measurements taken at the southern end of the Salt Lake City Valley within the Jordan Narrows. These measurements include wind profiler, surface, lidar, radiosonde, multi-layered tether-sonde and sodar measurements. We are also collaborating with other VTMX investigators through linking our measurements within the Jordan Narrows with their investigations. The instrumentation was provided to interested VTMX investigators and was used extensively. Thus the NCAR data set played a large role in the results of the overall experiment. Our work under this proposal includes analysis of the observations, mesoscale modeling efforts in support of our VTMX analysis and general instrumentation development aimed at improving the measurement of vertical transport and mixing under stable conditions. This report is subdivided by research objectives.
Date: February 13, 2007
Creator: Parsons, David; Pinto, James; Brown, William; Cohn, Stephen & Morley, Bruce
Object Type: Report
System: The UNT Digital Library

Battery Choices and Potential Requirements for Plug-In Hybrids

Plug-in Hybrid vehicles energy storage and drive cycle impacts presentation given at the 7th Advanced Automotive Battery Conference.
Date: February 13, 2007
Creator: Pesaran, A.
Object Type: Presentation
System: The UNT Digital Library
FACILITY UPGRADES FOR RECEIPT FROM ACTINIDE REMOVAL AND MODULAR CAUSTIC SIDE SOLVENT EXTRACTION PROCESSES AT THE SAVANNAH RIVER SITE (open access)

FACILITY UPGRADES FOR RECEIPT FROM ACTINIDE REMOVAL AND MODULAR CAUSTIC SIDE SOLVENT EXTRACTION PROCESSES AT THE SAVANNAH RIVER SITE

The Savannah River Site (SRS) is currently on an aggressive program to empty its High Level Waste (HLW) tanks and immobilize its radioactive waste into a durable borosilicate glass in the Defense Waste Processing Facility (DWPF). As a part of that program, two new processes will be brought on-line to assist in emptying the HLW tanks. These processes are in addition to the current sludge removal process and are called the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction (MCU) Process. In order to accept and process the streams generated from these two new processes, several facility modifications are required and are broken down into several projects. These projects are handling the facility modifications required for the Tank Farm (241-96H), and DWPF vitrification facility (221-S), and DWPF ancillary facilities (511-S, and 512-S). Additional modifications to the 221-S building were required to address the flammability concern from the solvent carryover from the MCU process. This paper will describe a summary of the modifications impacting the 511-S, 512-S, and the 221-S facilities in order to receive the new streams from the ARP and MCU processes at the DWPF.
Date: February 13, 2007
Creator: Fellinger, T; Stephen Phillips, S; Benjamin Culbertson, B; Beverly02 Davis, B & Aaron Staub, A
Object Type: Article
System: The UNT Digital Library
TECHNICAL BASIS DOCUMENT FOR CRITERIA AND PROCESSES FOR THE CERTIFICATION OF NON-RADIOACTIVE HAZARDOUS AND NON-HAZARDOUS WASTES (open access)

TECHNICAL BASIS DOCUMENT FOR CRITERIA AND PROCESSES FOR THE CERTIFICATION OF NON-RADIOACTIVE HAZARDOUS AND NON-HAZARDOUS WASTES

This Technical Basis Document (TBD) identifies how the values presented in the ''Criteria and Processes for the Certification of Non-Radioactive Hazardous and Non-Hazardous Wastes'' were derived. The original moratorium document (UCRL-AR-109662) applied only to hazardous wastes generated in Radioactive Materials Management Areas (RMMAs) that were destined for off-site Treatment, Storage, and Disposal Facilities (TSDFs) that did not possess a radioactive materials license. Since its inception, the original moratorium document has become the de facto free-release procedure for potentially volumetrically contaminated materials of all varieties. This was promulgated in a February 4, 1992 memo from Jyle Lytle, Deputy Assistant Secretary for Waste Management, entitled ''Update: Moratorium on Shipment of Potentially Radioactive Hazardous and Toxic Wastes''. In this memo, Ms. Lytle states, ''While the moratorium does not apply to non-hazardous/non-TSCA solid wastes and non-waste materials, the same release criteria apply''. Over the past few years, a considerable quantity of data and operating experience has been developed, which has shown the limitations of UCRL-AR-109662. The original Moratorium is out of date, and many of the organizations and procedures that it references are no longer in existence. In addition, the original document lacked sufficient detail to be used as an LLNL-wide procedure for free …
Date: February 13, 2007
Creator: Dominick, J & Gaylord, R
Object Type: Report
System: The UNT Digital Library
FY2008 Budget Documents: Internet Access and GPO Availability (open access)

FY2008 Budget Documents: Internet Access and GPO Availability

This report provides brief descriptions of the budget volumes and related documents, together with internet addresses Government Printing Office stock number, and prices to obtain the publications for FY 2008.
Date: February 13, 2007
Creator: Teefy, Jennifer
Object Type: Report
System: The UNT Digital Library
China’s Currency: A Summary of the Economic Issues (open access)

China’s Currency: A Summary of the Economic Issues

This report summarizes the information related to China's Currency, Economic issues, and options for the U.S. trade policies
Date: February 13, 2007
Creator: Morrison, Wayne M. & Labonte, Marc
Object Type: Report
System: The UNT Digital Library
Malaysia: Political, Security, Economic, and Trade Issues Considered (open access)

Malaysia: Political, Security, Economic, and Trade Issues Considered

None
Date: February 13, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The Quasi Government: Hybrid Organizations with Both Government and Private Sector Legal Characteristics (open access)

The Quasi Government: Hybrid Organizations with Both Government and Private Sector Legal Characteristics

None
Date: February 13, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Excessive CEO Pay: Background and Policy Approaches (open access)

Excessive CEO Pay: Background and Policy Approaches

This report provides Background and Policy Approaches about Excessive CEO Pay where average pay for non-management workers has stagnated after adjustment for inflation, falling slightly since the early 1970's.
Date: February 13, 2007
Creator: Shorter, Gary; Jickling, Mark & Raab, Alison
Object Type: Report
System: The UNT Digital Library
Sharing Law Enforcement and Intelligence Information: The Congressional Role (open access)

Sharing Law Enforcement and Intelligence Information: The Congressional Role

None
Date: February 13, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Bovine Spongiform Encephalopathy (BSE, or “Mad Cow Disease”): Current and Proposed Safeguards (open access)

Bovine Spongiform Encephalopathy (BSE, or “Mad Cow Disease”): Current and Proposed Safeguards

Through mid-Februray 2007, the United States had confirmed three cases of bovine spongiform encephalopathy (or "Mad Cow Disease"): the first in December 2003 in a Canadian-born cow found in Washington state, the second in June 2005 in cow in Texas, and the third in March 2006 in a cow in Alabama. This report contains information on the general issue, trade restrictions, the livestock 'feed ban', surveillance and testing in cattle, prevention in slaughter and processing, and related issues.
Date: February 13, 2007
Creator: Lister, Sarah A. & Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
India-U.S. Relations (open access)

India-U.S. Relations

This report briefs the context of India - U.S relations and also discusses its bilateral issues
Date: February 13, 2007
Creator: Kronstadt, K. Alan
Object Type: Report
System: The UNT Digital Library
Amber Alert Program Technology (open access)

Amber Alert Program Technology

This report discusses Amber Alerts (also referred to as AMBER plans), which use technology to disseminate information about child abductions in a timely manner.
Date: February 13, 2007
Creator: Moore, Linda K.
Object Type: Report
System: The UNT Digital Library