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Defense Space Activities: National Security Space Strategy Needed to Guide Future DOD Space Efforts (open access)

Defense Space Activities: National Security Space Strategy Needed to Guide Future DOD Space Efforts

Correspondence issued by the Government Accountability Office with an abstract that begins "The United States depends on space assets to support national security activities as well as civil and commercial activities. The Department of Defense (DOD) depends on space assets to support a wide range of military missions to include intelligence collection; battlefield surveillance and management; global command, control, and communications; and navigation assistance. This operational dependence on space has placed new and increasing demands on current space systems and organizations to meet Joint Force Commanders' needs. Moreover, concerns have increased regarding emerging threats that could affect the United States' and other countries' access to the free use of space. GAO plans to issue a report regarding ORS acquisition issues by April 2008, and by July 2008 we will issue a report regarding how ORS is being developed to satisfy warfighter needs. However, GAO is providing Congress this letter because during the course of our work on how Operationally Responsive Space (ORS) is being developed to satisfy warfighter needs, GAO learned that the National Security Space Office developed a National Security Space Strategy in 2004, but it has not been issued. GAO is bringing this matter to Congress' attention because …
Date: March 27, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Separation of Yeast Cells from MS2 Viruses Using Acoustic Radiation Force (open access)

Separation of Yeast Cells from MS2 Viruses Using Acoustic Radiation Force

We report a rapid and robust separation of Saccharomyces cerevisiae and MS2 bacteriophage using acoustic focusing in a microfluidic device. A piezoelectric transducer (PZT) generates acoustic standing waves in the microchannel. These standing waves induce acoustic radiation force fields that direct microparticles towards the nodes (i.e., pressure minima) or the anti-nodes (i.e., pressure maxima) of the standing waves depending on the relative compressidensity between the particle and the suspending liquid.[1] For particles larger than 2 {micro}m, the transverse velocities generated by these force fields enable continuous, high throughput separation. Extensive work in the last decade [2-4] has demonstrated acoustic focusing for manipulating microparticles or biological samples in microfluidic devices. This prior work has primarily focused on experimental realization of acoustic focusing without modeling or with limited one-dimensional modeling estimates. We recently developed a finite element modeling tool to predict the two-dimensional acoustic radiation force field perpendicular to the flow direction in microfluidic devices.[1] Here we compare results from this model with experimental parametric studies including variations of the PZT driving frequencies and voltages as well as various particle sizes and compressidensities. These experimental parametric studies also provide insight into the development of an adjustable 'virtual' pore-size filter as well as …
Date: March 27, 2008
Creator: Jung, B.; Fisher, K.; Ness, K.; Rose, K. A. & Mariella, R. P., Jr.
Object Type: Article
System: The UNT Digital Library
Project Title: Nuclear Astrophysics Data from Radioactive Beam Facilities (open access)

Project Title: Nuclear Astrophysics Data from Radioactive Beam Facilities

The scientific aims of this project have been the evaluation and dissemination of key nuclear reactions in nuclear astrophysics, with a focus on ones to be studied at new radioactive beam facilities worldwide. These aims were maintained during the entire funding period from 2003 - 2006. In the following, a summary of the reactions evaluated during this period is provided. Year 1 (2003-04): {sup 21}Na(p,{gamma}){sup 22}Mg and {sup 18}Ne({alpha},p){sup 21}Na - The importance of the {sup 21}Na(p,{gamma}){sup 22}Mg and the {sup 18}Ne({alpha},p){sup 21}Na reactions in models of exploding stars has been well documented: the first is connected to the production of the radioisotope {sup 22}Na in nova nucleosynthesis, while the second is a key bridge between the Hot-CNO cycles and the rp-process in X-ray bursts. By the end of Summer 2004, our group had updated these reaction rates to include all published data up to September 2004, and cast the reaction rates into standard analytical and tabular formats with the assistance of Oak Ridge National Laboratory's computational infrastructure for reaction rates. Since September 2004, ongoing experiments on these two reactions have been completed, with our group's participation in both: {sup 21}Na(p,{gamma}){sup 22}Mg at the TRIUMF-ISAC laboratory (DRAGON collaboration), and 18Ne({alpha},p){sup …
Date: March 27, 2008
Creator: Chen, Alan A.
Object Type: Report
System: The UNT Digital Library
Least Squares Magnetic-Field Optimization for Portable Nuclear Magnetic Resonance Magnet Design (open access)

Least Squares Magnetic-Field Optimization for Portable Nuclear Magnetic Resonance Magnet Design

Single-sided and mobile nuclear magnetic resonance (NMR) sensors have the advantages of portability, low cost, and low power consumption compared to conventional high-field NMR and magnetic resonance imaging (MRI) systems. We present fast, flexible, and easy-to-implement target field algorithms for mobile NMR and MRI magnet design. The optimization finds a global optimum ina cost function that minimizes the error in the target magnetic field in the sense of least squares. When the technique is tested on a ring array of permanent-magnet elements, the solution matches the classical dipole Halbach solution. For a single-sided handheld NMR sensor, the algorithm yields a 640 G field homogeneous to 16 100 ppm across a 1.9 cc volume located 1.5 cm above the top of the magnets and homogeneous to 32 200 ppm over a 7.6 cc volume. This regime is adequate for MRI applications. We demonstrate that the homogeneous region can be continuously moved away from the sensor by rotating magnet rod elements, opening the way for NMR sensors with adjustable"sensitive volumes."
Date: March 27, 2008
Creator: Paulsen, Jeffrey L; Franck, John; Demas, Vasiliki & Bouchard, Louis-S.
Object Type: Article
System: The UNT Digital Library
Argonne National Laboratory Summary Site Environmental Report for Calendar Year 2006. (open access)

Argonne National Laboratory Summary Site Environmental Report for Calendar Year 2006.

This booklet is designed to inform the public about what Argonne National Laboratory is doing to monitor its environment and to protect its employees and neighbors from any adverse environmental impacts from Argonne research. The Downers Grove South Biology II class was selected to write this booklet, which summarizes Argonne's environmental monitoring programs for 2006. Writing this booklet also satisfies the Illinois State Education Standard, which requires that students need to know and apply scientific concepts to graduate from high school. This project not only provides information to the public, it will help students become better learners. The Biology II class was assigned to condense Argonne's 300-page, highly technical Site Environmental Report into a 16-page plain-English booklet. The site assessment relates to the class because the primary focus of the Biology II class is ecology and the environment. Students developed better learning skills by working together cooperatively, writing and researching more effectively. Students used the Argonne Site Environmental Report, the Internet, text books and information from Argonne scientists to help with their research on their topics. The topics covered in this booklet are the history of Argonne, groundwater, habitat management, air quality, Argonne research, Argonne's environmental non-radiological program, radiation, and …
Date: March 27, 2008
Creator: Golchert, N. W. & Oversight, ESH /QA
Object Type: Report
System: The UNT Digital Library
SHIELDING ANALYSIS FOR X-RAY SOURCES GENERATED IN TARGET CHAMBER OF THE NATIONAL IGNITION FACILITY (open access)

SHIELDING ANALYSIS FOR X-RAY SOURCES GENERATED IN TARGET CHAMBER OF THE NATIONAL IGNITION FACILITY

Prompt doses from x-rays generated as result of laser beam interaction with target material are calculated at different locations inside the National Ignition Facility (NIF). The maximum dose outside a Target Chamber diagnostic port is {approx} 1 rem for a shot utilizing the 192 laser beams and 1.8 MJ of laser energy. The dose during a single bundle shot (8 laser beams) drops to {approx} 40 mrem. Doses calculated outside the Target Bay doors and inside the Switchyards (except for the 17 ft.-6 in. level) range from a fraction of mrem to about 11 mrem for 192 beams, and scales down proportionally with smaller number of beams. At the 17ft.-6 in. level, two diagnostic ports are directly facing two of the Target Bay doors and the maximum doses outside the doors are 51 and 15.5 mrem, respectively. Shielding each of the two Target Bay doors with 1/4 in. Pb reduces the dose by factor of fifty. One or two bundle shots (8 to 16 laser beams) present a small hazard to personnel in the Switchyards.
Date: March 27, 2008
Creator: Khater, H Y; Brereton, S J & Singh, M S
Object Type: Article
System: The UNT Digital Library
TECHNICAL EVALUATION OF ELECTRICAL RESISTIVITY METHODS AT THE DEPARTMENT OF ENERGY HANFORD SITE (open access)

TECHNICAL EVALUATION OF ELECTRICAL RESISTIVITY METHODS AT THE DEPARTMENT OF ENERGY HANFORD SITE

None
Date: March 27, 2008
Creator: SW, PETERSEN
Object Type: Report
System: The UNT Digital Library
S-102 Transfer Pump Restriction Modeling Results (open access)

S-102 Transfer Pump Restriction Modeling Results

It was determined that a radioactive waste leak in the Hanford S Farm in the vicinity of the S-102 retrieval pump discharge occurred because of over-pressurization and failure of the S-102 dilution water supply hose while operating the retrieval pump in reverse with an obstructed suction cavity and an unobstructed flow path to the dilution water supply hose. This report describes efforts to identify plausible scenarios for the waste leak to occur.
Date: March 27, 2008
Creator: Wells, Beric E.; Johnson, Kenneth I.; Rector, David R. & Trent, Donald S.
Object Type: Report
System: The UNT Digital Library
HYDROGEN EFFECTS ON THE BURST PROPERTIES OF TYPE 304L STAINLESS STEEL FLAWED VESSELS (open access)

HYDROGEN EFFECTS ON THE BURST PROPERTIES OF TYPE 304L STAINLESS STEEL FLAWED VESSELS

The effect of hydrogen on the burst properties Type 304L stainless steel vessels was investigated. The purpose of the study was to compare the burst properties of hydrogen-exposed stainless steel vessels burst with different media: water, helium gas, or deuterium gas. A second purpose of the tests was to provide data for the development of a predictive finite-element model. The burst tests were conducted on hydrogen-exposed and unexposed axially-flawed cylindrical vessels. The results indicate that samples burst pneumatically had lower volume ductility than those tested hydraulically. Deuterium gas tests had slightly lower ductility than helium gas tests. Burst pressures were not affected by burst media. Hydrogen-charged samples had lower volume ductility and slightly higher burst pressures than uncharged samples. Samples burst with deuterium gas fractured by quasi-cleavage near the inside wall. The results of the tests were used to improve a previously developed predictive finite-element model. The results show that predicting burst behavior requires as a material input the effect of hydrogen on the plastic strain to fracture from tensile tests. The burst test model shows that a reduction in the plastic strain to fracture of the material will result in lower volume ductility without a reduction in burst pressure …
Date: March 27, 2008
Creator: Morgan, M; Monica Hall, M; Ps Lam, P & Dean Thompson, D
Object Type: Article
System: The UNT Digital Library
Improved Bacterial and Viral Recoveries from 'Complex' Samples using Electrophoretically Assisted Acoustic Focusing (open access)

Improved Bacterial and Viral Recoveries from 'Complex' Samples using Electrophoretically Assisted Acoustic Focusing

Automated front-end sample preparation technologies can significantly enhance the sensitivity and reliability of biodetection assays [1]. We are developing advanced sample preparation technologies for biowarfare detection and medical point-of-care diagnostics using microfluidic systems with continuous sample processing capabilities. Here we report an electrophoretically assisted acoustic focusing technique to rapidly extract and enrich viral and bacterial loads from 'complex samples', applied in this case to human nasopharyngeal samples as well as simplified surrogates. The acoustic forces capture and remove large particles (> 2 {micro}m) such as host cells, debris, dust, and pollen from the sample. We simultaneously apply an electric field transverse to the flow direction to transport small ({le} 2 {micro}m), negatively-charged analytes into a separate purified recovery fluid using a modified H-filter configuration [Micronics US Patent 5,716,852]. Hunter and O'Brien combined transverse electrophoresis and acoustic focusing to measure the surface charge on large particles, [2] but to our knowledge, our work is the first demonstration combining these two techniques in a continuous flow device. Marina et al. demonstrated superimposed dielectrophoresis (DEP) and acoustic focusing for enhanced separations [3], but these devices have limited throughput due to the rapid decay of DEP forces. Both acoustic standing waves and electric fields …
Date: March 27, 2008
Creator: Ness, K.; Rose, K.; Jung, B.; Fisher, K. & Mariella, R. P., Jr.
Object Type: Article
System: The UNT Digital Library
2006 Lawrence Livermore National Laboratory Annual Illness and Injury Surveillance Report (open access)

2006 Lawrence Livermore National Laboratory Annual Illness and Injury Surveillance Report

The U.S. Department of Energy’s (DOE) commitment to assuring the health and safety of its workers includes the conduct of illness and injury surveillance activities that provide an early warning system to detect health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: March 27, 2008
Creator: United States. Department of Energy. Office of Health, Safety, and Security.
Object Type: Report
System: The UNT Digital Library
L-Shell Spectroscopy of Au as a Temperature Diagnostic Tool (open access)

L-Shell Spectroscopy of Au as a Temperature Diagnostic Tool

In order to develop plasma diagnostic for reduced-size hot hohlraums under laser irradiation, they have studied the L-shell emission from highly charged gold ions in the SuperEBIT electron beam ion trap. The resolving power necessary to identify emission features from individual charge states in a picket fence pattern has been estimated, and the observed radiation features have been compared with atomic structure calculations. They find that the strong 3d{sub 5/2} {yields} 2p{sub 3/2} emission features are particularly useful in determining the charge state distribution and average ion charge <Z>, which are strongly sensitive to the electron temperature.
Date: March 27, 2008
Creator: Trabert, E; Hansen, S B; Beiersdorfer, P; Brown, G V; Widmann, K & Chung, H K
Object Type: Article
System: The UNT Digital Library

Renewable Energy Financing: The Role of Policy and Economics

Renewable portfolio standards (RPS) have rapidly developed momentum in certain sections of the United States and throughout the world, primarily in response to climate and energy security concerns. This presentation at the RPS Symposium, sponsored by the Electric Utility Consultants Inc., will discuss renewable energy financing and the economics of such policies.
Date: March 27, 2008
Creator: Cory, K.
Object Type: Presentation
System: The UNT Digital Library
Resonant Auger Effect at High X-Ray Intensity (open access)

Resonant Auger Effect at High X-Ray Intensity

The resonant Auger effect of atomic neon exposed to high-intensity x-ray radiation in resonance with the 1s {yields} 3p transition is discussed. High intensity here means that the x-ray peak intensity is sufficient ({approx} 10{sup 18} W/cm{sup 2}) to induce Rabi oscillations between the neon ground state and the 1s{sup -1}3p ({sup 1}P) state within the relaxation lifetime of the inner-shell vacancy. For the numerical analysis presented, an effective two-level model, including a description of the resonant Auger decay process, is employed. Both coherent and chaotic x-ray pulses are treated. The latter are used to simulate radiation from x-ray free-electron lasers based on the principle of self-amplified spontaneous emission. Observing x-ray-driven atomic population dynamics in the time domain is challenging for chaotic pulse ensembles. A more practical option for experiments using x-ray free-electron lasers is to measure the line profiles in the kinetic energy distribution of the resonant Auger electron. This provides information on both atomic population dynamics and x-ray pulse properties.
Date: March 27, 2008
Creator: Rohringer, N & Santra, R
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 39, No. 92, Ed. 1 Thursday, March 27, 2008 (open access)

Greensheet (Houston, Tex.), Vol. 39, No. 92, Ed. 1 Thursday, March 27, 2008

Free weekly newspaper that includes business and classified advertising.
Date: March 27, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 39, No. 93, Ed. 1 Thursday, March 27, 2008 (open access)

Greensheet (Houston, Tex.), Vol. 39, No. 93, Ed. 1 Thursday, March 27, 2008

Free weekly newspaper that includes business and classified advertising.
Date: March 27, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Russian Energy Policy Toward Neighboring Countries (open access)

Russian Energy Policy Toward Neighboring Countries

This report begins with a brief discussion of the Russian oil and gas industries, including their efforts to purchase energy infrastructure in central and Eastern Europe and reduce energy subsidies to neighboring countries. A second section deals with the impact of recent Russian energy policy on neighboring countries, all of them formerly part of the Soviet Union, de facto or de jure, and all heavily dependent on Russian energy imports.
Date: March 27, 2008
Creator: Woehrel, Steven
Object Type: Report
System: The UNT Digital Library
Nuclear Fuel Reprocessing: U.S. Policy Development (open access)

Nuclear Fuel Reprocessing: U.S. Policy Development

This report discusses the reprocessing of nuclear fuel that refers to the chemical separation of fissionable uranium and plutonium from irradiated nuclear fuel.
Date: March 27, 2008
Creator: Andrews, Anthony
Object Type: Report
System: The UNT Digital Library
North Texas Daily (Denton, Tex.), Vol. 91, No. 39, Ed. 1 Thursday, March 27, 2008 (open access)

North Texas Daily (Denton, Tex.), Vol. 91, No. 39, Ed. 1 Thursday, March 27, 2008

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: March 27, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Texas Jewish Post (Fort Worth, Tex.), Vol. 62, No. 13, Ed. 1 Thursday, March 27, 2008 (open access)

Texas Jewish Post (Fort Worth, Tex.), Vol. 62, No. 13, Ed. 1 Thursday, March 27, 2008

Weekly Jewish newspaper from Fort Worth, Texas that includes local, state and national news along with extensive advertising.
Date: March 27, 2008
Creator: Wisch, Rene
Object Type: Newspaper
System: The Portal to Texas History
The Bastrop Advertiser (Bastrop, Tex.), Vol. 155, No. 9, Ed. 1 Thursday, March 27, 2008 (open access)

The Bastrop Advertiser (Bastrop, Tex.), Vol. 155, No. 9, Ed. 1 Thursday, March 27, 2008

Semi-weekly newspaper from Bastrop, Texas that includes local, state and national news along with advertising.
Date: March 27, 2008
Creator: McAuley, Davis
Object Type: Newspaper
System: The Portal to Texas History
The Canadian Record (Canadian, Tex.), Vol. 118, No. 13, Ed. 1 Thursday, March 27, 2008 (open access)

The Canadian Record (Canadian, Tex.), Vol. 118, No. 13, Ed. 1 Thursday, March 27, 2008

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.
Date: March 27, 2008
Creator: Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
Older Americans Act: FY2008 Funding and FY2009 Budget Request (open access)

Older Americans Act: FY2008 Funding and FY2009 Budget Request

None
Date: March 27, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Fischer-Tropsch Fuels from Coal, Natural Gas, and Biomass: Background and Policy (open access)

Fischer-Tropsch Fuels from Coal, Natural Gas, and Biomass: Background and Policy

This report provides background information and policy analysis regarding the ways to develop that directly and indirectly convert coal into liquid fuel.
Date: March 27, 2008
Creator: Andrews, Anthony & Logan, Jeffrey
Object Type: Report
System: The UNT Digital Library