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4th-International Symposium on Ultrafast Surface Science - Final Report (open access)

4th-International Symposium on Ultrafast Surface Science - Final Report

The 4-th International Symposium on Ultrafast Surface Dynamics (UDS4) was held at the Telluride Summer Research Center on June 22-27, 2003. The International Organizing Committee consisting of Hrvoje Petek (USA), Xiaoyang Zhu (USA), Pedro Echenique (Spain) and Maki Kawai (Japan) brought together a total of 51 participants 16 of whom were from Europe, 10 from Japan, and 25 from the USA. The focus of the conference was on ultrafast electron or light induced processes at well-defined surfaces. Ultrafast surface dynamics concerns the transfer of charge and energy at solid surfaces on the femtosecond time scale. These processes govern rates of fundamental steps in surface reactions, interfacial electron transfer in molecular electronics, and relaxation in spin transport. Recent developments in femtosecond laser technology make it possible to measure by a variety of nonlinear optical techniques directly in the time domain the microscopic rates underlying these interfacial processes. Parallel progress in scanning probe microscopy makes it possible at a single molecular level to perform the vibrational and electronic spectroscopy measurements, to induce reactions with tunneling electrons, and to observe their outcome. There is no doubt that successful development in the field of ultrafast surface dynamics will contribute to many important disciplines.
Date: January 26, 2005
Creator: Petek, Hrvoje
Object Type: Report
System: The UNT Digital Library
An Agent that can Prohibit Microbial Development and Infection (open access)

An Agent that can Prohibit Microbial Development and Infection

We have developed a process that makes use of double-stranded DNA:RNA hybrids to inhibit specific, targeted genetic activity completely within a cell. This process can be used in both human and bacterial cells. The agent that produces this effect can be inserted into a cell and remain quiescent for a considerable period of time without affecting cellular processes, until the gene against which it is targeted is induced. At this time the agent becomes effective, silencing the genetic response without affecting the host cell in any other way. When given as an anti-infective, this process may have significant use as an anti-bacterial, anti-viral agent. Our objective with this proposal is to develop the siHybrid concept sufficiently that it can be used as both an antibiotic and an antiviral agent.
Date: January 26, 2005
Creator: Christian, A
Object Type: Report
System: The UNT Digital Library
THE BNL SUPER NEUTRINO BEAM PROJECT. (open access)

THE BNL SUPER NEUTRINO BEAM PROJECT.

BNL plans to create a very long base line super neutrino beam facility by upgrading the AGS from the current 0.14 MW to 1.0 MW and beyond. The proposed facility consists of three major components. First is a 1.5 GeV superconducting linac to replace the booster as injector for the AGS, second is the performance upgrade of the AGS itself for higher intensity and repetition rate, and finally is the target and horn system for the neutrino production. The major contribution for the higher power is from the increase of the repetition rate of the AGS from 0.3 Hz to 2.5 Hz, with moderate increase from the intensity. The accelerator design considerations to achieve high intensity and low losses for the new linac and the AGS will be presented. The target and horn design for high power operation and easy maintenance will also be covered.
Date: January 26, 2005
Creator: Raparia, D.
Object Type: Article
System: The UNT Digital Library
CO2 Capture by Absorption with Potassium Carbonate (open access)

CO2 Capture by Absorption with Potassium Carbonate

The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. In Campaign 3 of the pilot plant, the overall mass transfer coefficient for the stripper with 7 m MEA decreased from 0.06 to 0.01 mol/(m{sup 3}.s.kPa) as the rich loading increased from 0.45 to 0.6 mol CO{sub 2}/mol MEA. Anion chromatography has demonstrated that nitrate and nitrite are major degradation products of MEA and PZ with pure oxygen. In measurements with the high temperature FTIR in 7 m MEA the MEA vapor pressure varied from 2 to 20 Pa at 35 to 70 C. In 2.5 m PZ the PZ vapor pressure varied from 0.2 to 1 Pa from 37 to 70 C.
Date: January 26, 2005
Creator: Rochelle, Gary T.; Hilliard, Marcus; Chen, Eric; Oyenekan, Babatunde; Dugas, Ross; McLees, John et al.
Object Type: Report
System: The UNT Digital Library
Complete Solution of Elastica for a Clamped-Hinged Beam, and Its Applications to a Carbon Nanotube (open access)

Complete Solution of Elastica for a Clamped-Hinged Beam, and Its Applications to a Carbon Nanotube

This paper treats an exact elastica solution for a clamped-hinged beam, and its application to a carbon nanotube. Although the elastica has a long history, and the exact post-buckling solution for the Euler buckling problem has been known for at least 150 years, it seems that the elastica solution obtained in this paper constitutes an addition to the existing family of elastica solutions. As an application of the results, a post-buckling analysis of a single wall carbon nanotube is studied. Also, a potential use of the posting-buckling analysis of the carbon nanotube for the determination of its Young's modulus has been indicated.
Date: January 26, 2005
Creator: Mikata, Y
Object Type: Article
System: The UNT Digital Library
Detecting and Attributing External Influences on the Climate System: A Review of Recent Advances (open access)

Detecting and Attributing External Influences on the Climate System: A Review of Recent Advances

We review recent research that assesses evidence for the detection of anthropogenic and natural external influences on the climate. Externally driven climate change has been detected by a number of investigators in independent data covering many parts of the climate system, including surface temperature on global and large regional scales, ocean-heat content, atmospheric circulation, and variables of the free atmosphere, such as atmospheric temperature and tropopause height. The influence of external forcing is also clearly discernible in reconstructions of hemispheric scale temperature of the last millennium. These observed climate changes are very unlikely to be due only to natural internal climate variability, and they are consistent with the responses to anthropogenic and natural external forcing of the climate system that are simulated with climate models. The evidence indicates that natural drivers such as solar variability and volcanic activity are at most partially responsible for the large-scale temperature changes observed over the past century, and that a large fraction of the warming over the last 50 years can be attributed to greenhouse gas increases. Thus the recent research supports and strengthens the IPCC Third Assessment Report conclusion that ''most of the global warming over the past 50 years is likely due …
Date: January 26, 2005
Creator: Barnett, T.; Zwiers, F.; Hegerl, G.; Allen, M.; Crowley, T.; Gillett, N. et al.
Object Type: Article
System: The UNT Digital Library
Effect of Stress Mitigation on Precipitation Kinetics of Alloy 22 Welds (open access)

Effect of Stress Mitigation on Precipitation Kinetics of Alloy 22 Welds

Understanding the phase stability of Alloy 22 (N06022) is important since the precipitation of tetrahedrally close-packed (TCP) phases over time has been known to adversely affect corrosion and mechanical properties. Prior observations have shown that these phases precipitate during the welding process. After welding, residual stresses due to the solidification and cooling from temperature remain. When the weld cannot be stress-relieved by solution annealing, the application of commercially available stress-mitigation processes such as low plasticity burnishing (LPB) and laser shock peening (LSP) may be used to produce near-surface compressive stresses. This study involved examination of cross-sectional samples of aged 1.25 inch thick welds of Alloy 22 plates using electron backscatter diffraction (EBSD) for TCP identification and micrograph analysis for TCP quantification. Precipitation in both the as-welded and LSP weld was observed primarily in inter-dendritic regions whilst precipitation in the LPB weld was in both inter- and intra-dendritic regions.
Date: January 26, 2005
Creator: El-Dasher, B S & Torres, S G
Object Type: Article
System: The UNT Digital Library
Experimental Measurements of Delayed Fission Product Gamma-Ray Transmission Through Low Enriched UO2 Fuel Pin Lattices in Air (open access)

Experimental Measurements of Delayed Fission Product Gamma-Ray Transmission Through Low Enriched UO2 Fuel Pin Lattices in Air

Experimental measurements of delayed fission-product gamma-ray transmission through low-enriched UO{sub 2} fuel pin lattices in an air medium were conducted at the Rensselaer Polytechnic Institute Reactor Critical Facility (RCF). The RCF core consists of excess Special Power Excursion Reactor Test (SPERT) fuel pins, enriched to 4.81 weight percent {sup 235}U, clad in stainless steel. An experimental apparatus was constructed to hold various arrangements of fuel pin lattices. The arrangements consisted of a single activated source pin taken from the reactor core surrounded by inactive fuel pins in an air medium. A sodium-iodide detector and gamma-ray spectroscopy system was used to generate a pulse-height spectrum of the gamma-ray radiation for detector positions outside the lattice. The change in radiation intensity as the detector is rotated about the vertical axis of the lattice, the ''channeling effect,'' was measured. Experimental measurements of the channeling effect were performed for six arrangements; 3 x 3, 5 x 5, and 7 x 7 lattices, with both the comer position and center position containing the activated pin. The results of the measurements demonstrate that the gamma-ray radiation intensity can vary widely, as a function of angle, relative to the vertical axis of the lattice.
Date: January 26, 2005
Creator: Trumbull, T & Harris, D
Object Type: Article
System: The UNT Digital Library
Federal Procurement: International Agreements Result in Waivers of Some U.S. Domestic Source Restrictions (open access)

Federal Procurement: International Agreements Result in Waivers of Some U.S. Domestic Source Restrictions

A letter report issued by the Government Accountability Office with an abstract that begins "Over the years, Congress has enacted a variety of laws designed to encourage federal agencies to purchase U.S. supplies and services. These laws are commonly referred to as domestic preference laws or domestic source restrictions. Perhaps the best known of these laws is the Buy American Act, a 1933 law that established a statutory preference for U.S. supplies and construction materials. At the same time, Congress has approved a number of international agreements that open certain government procurements to goods and services from countries that are parties to those agreements. In addition, the Department of Defense (DOD) has entered into reciprocal procurement memoranda of understanding (MOUs) with some of its foreign counterparts, under which DOD may procure goods and services from those countries. Congress asked us to determine the effect of international agreements on the applicability of U.S. domestic source restrictions. In response, this report (1) identifies the current international trade agreements to which the U.S. is a party that contain government procurement provisions, as well as the reciprocal defense procurement MOUs, and (2) describes how these trade agreements and MOUs affect the applicability of selected …
Date: January 26, 2005
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Fruits, Vegetables, and Other Specialty Crops: A Primer on Government Programs (open access)

Fruits, Vegetables, and Other Specialty Crops: A Primer on Government Programs

U.S. farmers grow more than 250 types of fruit, vegetable, tree nut, flower, ornamental nursery, and turfgrass crops in addition to the major bulk commodity crops. Although specialty crops are ineligible for the federal commodity price and income support programs, they are eligible for other types of U.S. Department of Agriculture (USDA) support, such as crop insurance, disaster assistance, and, under certain conditions, ad hoc market loss assistance payments. This report describes the federal programs of importance to the specialty crop sector, and provides the most recent funding information available for them.
Date: January 26, 2005
Creator: Rawson, Jean M.
Object Type: Report
System: The UNT Digital Library
Gasoline Prices: New Legislation and Proposals (open access)

Gasoline Prices: New Legislation and Proposals

This report discusses policy options for Congress regarding gas prices. The high price of gasoline was an important consideration during the debate on major energy legislation, which ended August 8 as the President signed the Energy Policy Act of 2005, H.R. 6 (P.L. 109-58). However, prices continued to surge, spiking at the end of August when Hurricane Katrina shut down refining operations in the Gulf of Mexico. The continuing crisis renewed attention to some issues that were dropped or compromised in the debate over P.L. 109-58. A large number of factors combined to put pressure on gasoline prices, including increased world demand for crude oil and U.S. refinery capacity inadequate to supply gasoline to a recovering national economy. The war and continued violence in Iraq added uncertainty and a threat of supply disruption that added pressure particularly to the commodity futures markets.
Date: January 26, 2005
Creator: Behrens, Carl E. & Glover, Carol
Object Type: Report
System: The UNT Digital Library
The Groundwater Performance Assessment Project Quality Assurance Plan (open access)

The Groundwater Performance Assessment Project Quality Assurance Plan

This document provides the quality assurance guidelines that will be followed by the groundwater project.
Date: January 26, 2005
Creator: Walker, Thomas G.
Object Type: Report
System: The UNT Digital Library
Helium Pot System for Maintaining Sample Temperature after Cryocooler Deactivation (open access)

Helium Pot System for Maintaining Sample Temperature after Cryocooler Deactivation

A system for maintaining a sample at a constant temperature below 10K after deactivating the cooling source is demonstrated. In this system, the cooling source is a GM cryocooler that is joined with the sample through an adaptor that consists of a helium pot and a resistive medium. Upon deactivating the cryocooler, the power applied to a heater located on the sample side of the resistive medium is decreased gradually to maintain an appropriate temperature rise across the resistive medium as the helium pot warms. The temperature is held constant in this manner without the use of solid or liquid cryogens and without mechanically disconnecting the sample from the cooler. Shutting off the cryocooler significantly reduces sample motion that results from vibration and expansion/contraction of the cold head housing. The reduction in motion permits certain processes that are very sensitive to sample position stability, but are not performed throughout the duration that the sample is at low-temperature. An apparatus was constructed to demonstrate this technique using a 4K GM cryocooler. Experimental and theoretical predictions indicate that when the helium pot is pressurized to the working pressure of the cryocooler's helium supply, a sample with continuous heat dissipation of several-hundred milliwatts …
Date: January 26, 2005
Creator: Haid, B J
Object Type: Article
System: The UNT Digital Library
Implications of the Vienna Convention on Consular Relations upon the Regulation of Consular Identification Cards (open access)

Implications of the Vienna Convention on Consular Relations upon the Regulation of Consular Identification Cards

This report discusses controversy surrounding the usage of consular identification cards within the United States. It identifies any potential implications that issuing these cards would have with regards to the Vienna Convention on Consular Relations.
Date: January 26, 2005
Creator: Elsea, Jennifer K. & Garcia, Michael John
Object Type: Report
System: The UNT Digital Library
Large Eddy Simulation of Stable Boundary Layer Turbulent Processes in Complex Terrain (open access)

Large Eddy Simulation of Stable Boundary Layer Turbulent Processes in Complex Terrain

Research was performed using a turbulence boundary layer model to study the behavior of cold, dense flows in regions of complex terrain. Results show that flows develop a balance between turbulent entrainment of warm ambient air and dense, cold air created by surface cooling. Flow depth and strength is a function of downslope distance, slope angle and angle changes, and the ambient air temperature.
Date: January 26, 2005
Creator: Skyllingstad, Eric D.
Object Type: Report
System: The UNT Digital Library
Lasers Aimed at Aircraft Cockpits: Background and Possible Options to Address the Threat to Aviation Safety and Security (open access)

Lasers Aimed at Aircraft Cockpits: Background and Possible Options to Address the Threat to Aviation Safety and Security

A recent rash of incidents involving lasers aimed at aircraft cockpits has raised concerns over the potential threat to aviation safety and security. While none of these incidents has been linked to terrorism, security officials have expressed concern that terrorists may seek to acquire and use higher-powered lasers to, among other things, incapacitate pilots. There is also growing concerned among aviation safety experts that the ubiquity and low cost of handheld laser devices could increase the number of incidents where pilots are distracted or temporarily incapacitated during critical phases of flight. Possible options to mitigate the threat of lasers include restricting the sale or use of certain laser devices; amending criminal statutes associated with interfering with flight operations; providing pilots with laser eye protection; expanding and enforcing laser free zones around airports; and educating the public regarding the risks of lasers to aviation safety. This report will be updated as needed.
Date: January 26, 2005
Creator: Elias, Bartholomew
Object Type: Report
System: The UNT Digital Library
Low-Temperature Agining Behavior of U-6 wt% Nb (open access)

Low-Temperature Agining Behavior of U-6 wt% Nb

Phase stability and aging mechanisms in a water-quenched (WQ) U-6wt% Nb (U-14at% Nb) alloy artificially aged at 200 C and naturally aged at ambient temperature for 15 years have been investigated and studied using Vickers-hardness measurement, X-ray diffraction (XRD) analysis, and transmission electron microscopy (TEM) techniques. Age hardening/softening phenomenon is recorded from the artificially aged samples based upon the microhardness measurement. The age hardening can be readily rationalized by the occurrence of fine-scaled Nb segregation, or spinodal decomposition, within the {alpha}'' domains, which results in the formation of a modulated structure containing nano-scaled Nb-rich and Nb-lean domains. Prolonged aging leads to age softening of the alloy by coarsening of the modulated structure. Chemical ordering, or disorder-order phase transformation, is found within the naturally aged alloy according to TEM observations of antiphase domain boundaries (APBs) and superlattice diffraction patterns. A possible superlattice structure for the ordered {alpha}'' phase observed in the naturally aged sample and underlying low-temperature aging mechanisms are proposed.
Date: January 26, 2005
Creator: Hsiung, L L
Object Type: Article
System: The UNT Digital Library
Middleware for Astronomical Data Analysis Pipelines (open access)

Middleware for Astronomical Data Analysis Pipelines

In this paper the authors describe the approach to research, develop, and evaluate prototype middleware tools and architectures. The developed tools can be used by scientists to compose astronomical data analysis pipelines easily. They use the SuperMacho data pipelines as example applications to test the framework. they describe their experience from scheduling and running these analysis pipelines on massive parallel processing machines. they use MCR a Linux cluster machine with 1152 nodes and Luster parallel file system as the hardware test-bed to test and enhance the scalability of the tools.
Date: January 26, 2005
Creator: Abdulla, G.; Liu, D.; Garlick, J.; Miller, M.; Nikolaev, S.; Cook, K. et al.
Object Type: Article
System: The UNT Digital Library
Military Medical Care Services: Questions and Answers (open access)

Military Medical Care Services: Questions and Answers

This report attempts to answer basic questions about the Military Health Services System (MHSS), its beneficiary population, the medical services it provides, its costs, and major changes that are underway or have been proposed. Citations are made to more detailed CRS studies where appropriate.
Date: January 26, 2005
Creator: Best, Richard A., Jr.
Object Type: Report
System: The UNT Digital Library
[Minutes: Intelligence Joint Cross-Service Group, January 26, 2005] (open access)

[Minutes: Intelligence Joint Cross-Service Group, January 26, 2005]

BRAC 2005 Intelligence Joint Cross-Service Group Meeting Minutes of January 26, 2005. The document is redacted, and the meeting minutes were withheld as classified information.
Date: January 26, 2005
Creator: United States. Department of Defense.
Object Type: Text
System: The UNT Digital Library
Monitoring Gene Expression In Vivo with Nucleic Acid Molecular Switches (open access)

Monitoring Gene Expression In Vivo with Nucleic Acid Molecular Switches

The overall objectives of this project were (1) to develop allosteric ribozymes capable of acting as molecular switches for monitoring the levels of both wild-type and mutant mRNA species in living cells and whole animals and (2) to develop highly efficient reagents to deliver nucleic acid molecular switches into living cells, tissues and animals with the ultimate goal of expression profiling specific mRNAs of diagnostic or prognostic value within tumors in animals. During the past year, we have moved our laboratory to Nevada and in the moving process we have lost electronic and paper copies of prior progress reports concerning the construction and biological properties of the molecular switches. Since there was minimal progress during the last year on molecular switches, we are relying on past project reports to provide a summary of our data on this facet of the grant. Here we are summarizing the work done on the delivery reagents and their application to inducing mutations in living cells, which will include work done during the no cost extension.
Date: January 26, 2005
Creator: Ward, David C. & Bray-Ward, Patricia
Object Type: Report
System: The UNT Digital Library
PHASE II CALDERON PROCESS TO PRODUCE DIRECT REDUCED IRON RESEARCH AND DEVELOPMENT PROJECT (open access)

PHASE II CALDERON PROCESS TO PRODUCE DIRECT REDUCED IRON RESEARCH AND DEVELOPMENT PROJECT

This project was initially targeted to the making of coke for blast furnaces by using proprietary technology of Calderon in a phased approach, and Phase I was successfully completed. The project was then re-directed to the making of iron units. In 2000, U.S. Steel teamed up with Calderon for a joint effort which will last 42 months to produce directly reduced iron with the potential of converting it into molten iron or steel consistent with the Roadmap recommendations of 1998 prepared by the Steel Industry in cooperation with the Department of Energy by using iron ore concentrate and coal as raw materials, both materials being appreciably lower in cost than using iron pellets and coke.
Date: January 26, 2005
Creator: Calderon, Albert
Object Type: Report
System: The UNT Digital Library
POWs and MIAs: Status and Accounting Issues (open access)

POWs and MIAs: Status and Accounting Issues

None
Date: January 26, 2005
Creator: Goldich, Robert L.
Object Type: Report
System: The UNT Digital Library
Presidential Appointments to Full-Time Positions on Regulatory and Other Collegial Boards and Commissions, 108th Congress (open access)

Presidential Appointments to Full-Time Positions on Regulatory and Other Collegial Boards and Commissions, 108th Congress

None
Date: January 26, 2005
Creator: unknown
Object Type: Report
System: The UNT Digital Library