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Improved Biomass Utilization Through Remote Flow Sensing (open access)

Improved Biomass Utilization Through Remote Flow Sensing

The growth of the livestock industry provides a valuable source of affordable, sustainable, and renewable bioenergy, while also requiring the safe disposal of the large quantities of animal wastes (manure) generated at dairy, swine, and poultry farms. If these biomass resources are mishandled and underutilized, major environmental problems will be created, such as surface and ground water contamination, odors, dust, ammonia leaching, and methane emission. Anaerobic digestion of animal wastes, in which microorganisms break down organic materials in the absence of oxygen, is one of the most promising waste treatment technologies. This process produces biogas typically containing {approx}65% methane and {approx}35% carbon dioxide. The production of biogas through anaerobic digestion from animal wastes, landfills, and municipal waste water treatment plants represents a large source of renewable and sustainable bio-fuel. Such bio-fuel can be combusted directly, used in internal combustion engines, converted into methanol, or partially oxidized to produce synthesis gas (a mixture of hydrogen and carbon monoxide) that can be converted to clean liquid fuels and chemicals via Fischer-Tropsch synthesis. Different design and mixing configurations of anaerobic digesters for treating cow manure have been utilized commercially and/or tested on a laboratory scale. These digesters include mechanically mixed, gas recirculation mixed, …
Date: March 26, 2007
Creator: Al-Dahhan, Muthanna; Varma, Rajneesh; Karim, Khursheed; Vesvikar, Mehul; Hoffman, Rebecca; Depaoli, David et al.
Object Type: Report
System: The UNT Digital Library
Evaluation of ITER MSE Viewing Optics (open access)

Evaluation of ITER MSE Viewing Optics

The Motional Stark Effect (MSE) diagnostic on ITER determines the local plasma current density by measuring the polarization angle of light resulting from the interaction of a high energy neutral heating beam and the tokamak plasma. This light signal has to be transmitted from the edge and core of the plasma to a polarization analyzer located in the port plug. The optical system should either preserve the polarization information, or it should be possible to reliably calibrate any changes induced by the optics. This LLNL Work for Others project for the US ITER Project Office (USIPO) is focused on the design of the viewing optics for both the edge and core MSE systems. Several design constraints were considered, including: image quality, lack of polarization aberrations, ease of construction and cost of mirrors, neutron shielding, and geometric layout in the equatorial port plugs. The edge MSE optics are located in ITER equatorial port 3 and view Heating Beam 5, and the core system is located in equatorial port 1 viewing heating beam 4. The current work is an extension of previous preliminary design work completed by the ITER central team (ITER resources were not available to complete a detailed optimization of …
Date: March 26, 2007
Creator: Allen, S.; Lerner, S.; Morris, K.; Jayakumar, J.; Holcomb, C.; Makowski, M. et al.
Object Type: Report
System: The UNT Digital Library
Validation of Reinforced Concrete Modeling Capabilities for Seismic Response (open access)

Validation of Reinforced Concrete Modeling Capabilities for Seismic Response

None
Date: September 26, 2007
Creator: Alves, S W & Noble, C R
Object Type: Report
System: The UNT Digital Library
Prospects for Electron Imaging with Ultrafast Time Resolution (open access)

Prospects for Electron Imaging with Ultrafast Time Resolution

Many pivotal aspects of material science, biomechanics, and chemistry would benefit from nanometer imaging with ultrafast time resolution. Here we demonstrate the feasibility of short-pulse electron imaging with t10 nanometer/10 picosecond spatio-temporal resolution, sufficient to characterize phenomena that propagate at the speed of sound in materials (1-10 kilometer/second) without smearing. We outline resolution-degrading effects that occur at high current density followed by strategies to mitigate these effects. Finally, we present a model electron imaging system that achieves 10 nanometer/10 picosecond spatio-temporal resolution.
Date: January 26, 2007
Creator: Armstrong, M R; Reed, B W; Torralva, B R & Browning, N D
Object Type: Article
System: The UNT Digital Library
Status of the Nif Power Conditioning System (open access)

Status of the Nif Power Conditioning System

The NIF Power Conditioning System provides the pulsed excitation required to drive flashlamps in the laser's optical amplifiers. Modular in design, each of the 192 Main Energy Storage Modules (MESMs) storage up to 2.2 MJ of electrical energy in its capacitor bank before delivering the energy to 20 pairs of flashlamps in a 400 {micro}s pulse (10% power points). The peak current of each MESM discharge is 0.5 MA. Production, installation, commissioning and operation of the NIF Power Conditioning continue to progress rapidly, with the goals of completing accelerated production in late 2007 and finishing commissioning by early 2008, all the while maintaining an aggressive operations schedule. To date, more than 80% of the required modules have been assembled, shipped and installed in the facility, representing more that 240 MJ of stored energy available for driving NIF flashlamps. The MESMs have displayed outstanding reliability during daily, multiple-shift operations.
Date: July 26, 2007
Creator: Arnold, P.; Hulsey, S.; Ullery, G.; Petersen, D.; Pendleton, D.; Ollis, C. et al.
Object Type: Article
System: The UNT Digital Library
Reactive Membrane Barriers for Containment of Subsurface Contamination (open access)

Reactive Membrane Barriers for Containment of Subsurface Contamination

The overall goal of this project was to develop reactive membrane barriers--a new and flexible technique to contain and stabilize subsurface contaminants. Polymer membranes will leak once a contaminant is able to diffuse through the membrane. By incorporating a reactive material in the polymer, however, the contaminant is degraded or immobilized within the membrane. These processes increase the time for contaminants to breakthrough the barrier (i.e. the lag time) and can dramatically extend barrier lifetimes. In this work, reactive barrier membranes containing zero-valent iron (Fe{sup 0}) or crystalline silicotitanate (CST) were developed to prevent the migration of chlorinated solvents and cesium-137, respectively. These studies were complemented by the development of models quantifying the leakage/kill time of reactive membranes and describing the behavior of products produced via the reactions within the membranes. First, poly(vinyl alcohol) (PVA) membranes containing Fe{sup 0} and CST were prepared and tested. Although PVA is not useful in practical applications, it allows experiments to be performed rapidly and the results to be compared to theory. For copper ions (Cu{sup 2+}) and carbon tetrachloride, the barrier was effective, increasing the time to breakthrough over 300 times. Even better performance was expected, and the percentage of the iron used …
Date: February 26, 2007
Creator: Arnold, William A. & Cussler, Edward L.
Object Type: Report
System: The UNT Digital Library
A Search for B+ to tau+ nu (open access)

A Search for B+ to tau+ nu

The authors present a search for the decay B{sup +} {yields} {tau}{sup +}{nu} using 383 x 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. A sample of events with one reconstructed semileptonic B decay (B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}X) is selected, and in the recoil a search for B{sup +} {yields} {tau}{sup +}{nu} is performed. The {tau} is identified in the following channels: {tau}{sup +} {yields} e{sup +}{nu}{bar {nu}}, {tau}{sup +} {yields} {mu}{sup +}{nu}{bar {nu}}, {tau}{sup +} {yields} {pi}{sup +} {bar {nu}} and {tau}{sup +} {yields} {pi}{sup +}{pi}{sup 0}{bar {nu}}. They measure a branching fraction of {Beta}(B{sup +} {yields} {tau}{sup +}{nu}) = (0.9 {+-} 0.6(stat.) {+-} 0.1(syst.)) x 10{sup -4}. In the absence of a significant signal, we calculate an upper limit at the 90% confidence level of {Beta}(B{sup +} {yields} {tau}{sup +}{nu}) < 1.7 x 10{sup -4}. They calculate the product of the B meson decay constant f{sub B} and |V{sub ub}| to be f{sub B} {center_dot} |V{sub ub}| = (7.2{sub -2.8}{sup +2.0}(stat.) {+-} 0.2(syst.)) x 10{sup -4} GeV.
Date: June 26, 2007
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
ELECTRICAL SAFETY IMPROVEMENT PROJECT A COMPLEX WIDE TEAMING INITIATIVE (open access)

ELECTRICAL SAFETY IMPROVEMENT PROJECT A COMPLEX WIDE TEAMING INITIATIVE

This paper describes the results of a year-long project, sponsored by the Energy Facility Contractors Group (EFCOG) and designed to improve overall electrical safety performance throughout Department of Energy (DOE)-owned sites and laboratories. As evidenced by focused metrics, the Project was successful primarily due to the joint commitment of contractor and DOE electrical safety experts, as well as significant support from DOE and contractor senior management. The effort was managed by an assigned project manager, using classical project-management principles that included execution of key deliverables and regular status reports to the Project sponsor. At the conclusion of the Project, the DOE not only realized measurable improvement in the safety of their workers, but also had access to valuable resources that will enable them to do the following: evaluate and improve electrical safety programs; analyze and trend electrical safety events; increase electrical safety awareness for both electrical and non-electrical workers; and participate in ongoing processes dedicated to continued improvement.
Date: November 26, 2007
Creator: BJ, GRAY
Object Type: Article
System: The UNT Digital Library
DETAILED ANALYSIS OF THE MOST PROMISING ALTERNATIVES TO USING GRANULAR ACTIVATED CARBON TO TREAT 200-ZP-1 GROUNDWATER AND 200-PW-1 SOIL VAPOR (open access)

DETAILED ANALYSIS OF THE MOST PROMISING ALTERNATIVES TO USING GRANULAR ACTIVATED CARBON TO TREAT 200-ZP-1 GROUNDWATER AND 200-PW-1 SOIL VAPOR

This document presents a detailed evaluation of selected alternative treatment options to granular activated carbon (GAC) for removing carbon tetrachloride generated from the groundwater pump-and-treat system at the 200-ZP-I Operable Unit (OU) in the 200 West Area of the Hanford Site. This evaluation of alternative treatment options to GAC is also applicable to the vadose zone soil vapor extraction (SVE) system at the 200-PW-l OU, which is also located in the Hanford Site's 200 West Area.
Date: November 26, 2007
Creator: BYRNES ME, KALMAR JA
Object Type: Report
System: The UNT Digital Library
Mission Need Statement: Calcine Disposition Project Major Systems Acquisition Project (open access)

Mission Need Statement: Calcine Disposition Project Major Systems Acquisition Project

This document identifies the need to establish the Calcine Disposition Project to determine and implement the final disposition of calcine including characterization, retrieval, treatment (if necessary), packaging, loading, onsite interim storage pending shipment to a repository or interim storage facility, and disposition of related facilities.
Date: April 26, 2007
Creator: Beck, J. T.
Object Type: Report
System: The UNT Digital Library
Animal Identification: Overview and Issues (open access)

Animal Identification: Overview and Issues

Livestock industry groups, animal health officials, and the U.S. Department of Agriculture have been working to establish a nationwide identification system capable of quickly tracking animals from birth to slaughter, in order to combat a serious animal disease and/or to satisfy foreign market specifications. Some consumer groups are among those who believe animal identification also would be useful for food safety or retail labeling purposes. Some producers oppose new programs, fearing they will be costly and intrusive. In the 110th Congress as of 2007, one related bill (H.R. 1018) had been introduced; it would prohibit a mandatory program. Lawmakers could be asked to consider this or other measures on the topic, possibly as part of a 2007 farm bill.
Date: April 26, 2007
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
Country-of-Origin Labeling for Foods (open access)

Country-of-Origin Labeling for Foods

This report details the information related to Country-of-Origin labeling for foods.
Date: April 26, 2007
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
[The International Space Station and the Space Shuttle, April 26, 2007] (open access)

[The International Space Station and the Space Shuttle, April 26, 2007]

This report discusses the International Space Station (ISS) and efforts to improve shuttles and space exploration after the Columbia failure in 2003. Efforts include new policy from President Bush and funding for National Aeronautics and Space Administration (NASA). Updated April 26, 2007.
Date: April 26, 2007
Creator: Behrens, Carl E.
Object Type: Report
System: The UNT Digital Library
Gasoline Prices: Issues for the 110th Congress (open access)

Gasoline Prices: Issues for the 110th Congress

This report discusses the high prices of Gasoline and issues for the 110th Congress.
Date: April 26, 2007
Creator: Behrens, Carl E. & Glover, Carol
Object Type: Report
System: The UNT Digital Library
The European Union’s Energy Security Challenges (open access)

The European Union’s Energy Security Challenges

This report examines some of Europe's critical energy challenges and EU efforts to coordinate a common European energy strategy. It also includes an overview of broader transatlantic energy security cooperation.
Date: January 26, 2007
Creator: Belkin, Paul & Morelli, Vince L.
Object Type: Report
System: The UNT Digital Library
Superconducting Photoinjector (open access)

Superconducting Photoinjector

One of the frontiers in FEL science is that of high power. In order to reach power in the megawatt range, one requires a current of the order of one ampere with a reasonably good emittance. The superconducting laser-photocathode RF gun with a high quantum efficiency photocathode is the most natural candidate to provide this performance. The development of a 1/2 cell superconducting photoinjector designed to operate at up to a current of 0.5 amperes and beam energy of 2 MeV and its photocathode system are the subjects covered in this paper. The main issues are the photocathode and its insertion mechanism, the power coupling and High Order Mode damping. This technology is being developed at BNL for DOE nuclear physics applications such as electron cooling at high energy and electron ion colliders..
Date: August 26, 2007
Creator: Ben-Zvi,I.; Burrill, A.; Calaga, R.; Chang, X.; Grover, R.; Gupta, R. et al.
Object Type: Article
System: The UNT Digital Library
The Super Flavor Factory (open access)

The Super Flavor Factory

The main physics goals of a high luminosity e{sup +}e{sup -} flavor factory are discussed, including the possibilities to perform detailed studies of the CKM mechanism of quark mixing, and constrain virtual Higgs and Non-Standard Model particle contributions to the dynamics of rare B{sub u,d,s} decays. The large samples of D mesons and {tau} leptons produced at a flavor factory will result in improved sensitivities on D mixing and lepton flavor violation searches, respectively. One can also test fundamental concepts such as lepton universality to much greater precision than existing constraints and improve the precision on tests of CPT from B meson decays. Recent developments in accelerator physics have demonstrated the feasibility to build an accelerator that can achieve luminosities of {Omicron}(10{sup 36} cm{sup -2} s{sup -1}).
Date: January 26, 2007
Creator: Bevan, A.J. & /Queen Mary, U. of London
Object Type: Article
System: The UNT Digital Library
Hanford Site Environmental Surveillance Data Report for Calendar Year 2006 (open access)

Hanford Site Environmental Surveillance Data Report for Calendar Year 2006

This document includes tables of analytical data for Hanford Site environmental surveillance samples collected in 2006.
Date: September 26, 2007
Creator: Bisping, Lynn E.
Object Type: Report
System: The UNT Digital Library
A review of ground-based heavy-ion radiobiology relevant to space radiation risk assessment: Part II. Cardiovascular and immunological effects (open access)

A review of ground-based heavy-ion radiobiology relevant to space radiation risk assessment: Part II. Cardiovascular and immunological effects

The future of manned space flight depends on an analysis of the numerous potential risks of travel into deep space. Currently no radiation dose limits have been established for these exploratory missions. To set these standards more information is needed about potential acute and late effects on human physiology from appropriate radiation exposure scenarios, including pertinent radiation types and dose rates. Cancer risks have long been considered the most serious late effect from chronic daily relatively low-dose exposures to the complex space radiation environment. However, other late effects from space radiation exposure scenarios are under study in ground-based accelerator facilities and have revealed some unique particle radiation effects not observed with conventional radiations. A comprehensive review of pertinent literature that considers tissue effects of radiation leading to functional detriments in specific organ systems has recently been published (NCRP National Council on Radiation Protection and Measurements, Information Needed to Make Radiation Protection Recommendations for Space Missions Beyond Low-Earth Orbit, Report 153, Bethesda, MD, 2006). This paper highlights the review of two non-cancer concerns from this report: cardiovascular and immunological effects.
Date: February 26, 2007
Creator: Blakely, Eleanor A. & Chang, Polly Y.
Object Type: Article
System: The UNT Digital Library
Iraq: Oil and Gas Legislation, Revenue Sharing, and U.S. Policy (open access)

Iraq: Oil and Gas Legislation, Revenue Sharing, and U.S. Policy

This report reviews policy proposals and interim contracts, analyzes the positions of various Iraqi political actors, and discusses potential implications for U.S. foreign policy goals in Iraq.
Date: June 26, 2007
Creator: Blanchard, Christopher M.
Object Type: Report
System: The UNT Digital Library
Iraq: Foreign Contributions to Stabilization and Reconstruction. December 2007 (open access)

Iraq: Foreign Contributions to Stabilization and Reconstruction. December 2007

This report characterizes foreign contributions to Iraq in terms of personnel and resources, including trends over time, based on best-available information.
Date: December 26, 2007
Creator: Blanchard, Christopher M. & Dale, Catherine Marie
Object Type: Report
System: The UNT Digital Library
Magnetic Fields above the Surface of aSuperconductor with Internal Magnetism (open access)

Magnetic Fields above the Surface of aSuperconductor with Internal Magnetism

The author presents a method for calculating the magnetic fields near a planar surface of a superconductor with a given intrinsic magnetization in the London limit. He computes solutions for various magnetic domain boundary configurations and derives relations between the spectral densities of the magnetization and the resulting field in the vacuum half space, which are useful if the magnetization can be considered as a statistical quantity and its features are too small to be resolved individually. The results are useful for analyzing and designing magnetic scanning experiments. Application to existing data from such experiments on Sr{sub 2}RuO{sub 4} show that a domain wall would have been detectable, but the magnetic field of randomly oriented small domains and small defects may have been smaller than the experimental noise level.
Date: June 26, 2007
Creator: Bluhm, Hendrik & /Stanford U., Phys. Dept. /SLAC, SSRl
Object Type: Article
System: The UNT Digital Library
Effectiveness of Electrostatic Shielding and Electronic Subtraction to Correct for the Hole Trapping in Cdznte Semiconductor Detectors. (open access)

Effectiveness of Electrostatic Shielding and Electronic Subtraction to Correct for the Hole Trapping in Cdznte Semiconductor Detectors.

CdZnTe (CZT) is a very promising material for nuclear-radiation detectors. CZT detectors operate at ambient temperatures and offer high detection efficiency and excellent energy resolution, placing them ahead of high-purity Ge for those applications where cryogenic cooling is problematic. The progress achieved in CZT detectors over the past decade is founded on the developments of robust detector designs and readout electronics, both of which helped to overcome the effects of carrier trapping. Because the holes have low mobility, only electrons can be used to generate signals in thick CZT detectors, so one must account for the variation of the output signal versus the locations of the interaction points. To obtain high spectral resolution, the detector's design should provide a means to eliminate this dependence throughout the entire volume of the device. In reality, the sensitive volume of any ionization detector invariably has two regions. In the first, adjacent to the collecting electrode, the amplitude of the output signal rapidly increases almost to its maximum as the interaction point is located farther from the anode; in the rest of the volume, the output signal remains nearly constant. Thus, the quality of CZT detector designs can be characterized based on the magnitude …
Date: August 26, 2007
Creator: Bolotnikov, A. E.; Camarda, G. S.; Hossain, A.; Cui, Y. & James, R. B.
Object Type: Article
System: The UNT Digital Library
The Consumer Price Index: A Brief Overview (open access)

The Consumer Price Index: A Brief Overview

None
Date: February 26, 2007
Creator: Brain W. Cashell
Object Type: Report
System: The UNT Digital Library