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TRITIUM MOVEMENT AND ACCUMULATION IN THE NGNP SYSTEM INTERFACE AND HYDROGEN PLANT (open access)

TRITIUM MOVEMENT AND ACCUMULATION IN THE NGNP SYSTEM INTERFACE AND HYDROGEN PLANT

Tritium movement and accumulation in the Next Generation Nuclear Plant (NGNP) employing either a high-temperature electrolysis (HTE) process or a thermochemical water-splitting Sulfur-Iodine (SI) process to produce hydrogen is estimated by a numerical code, THYTAN, as a function of design, operational and material parameters. Estimated tritium concentrations in the hydrogen product and in the process chemicals of the hydrogen plant using the HTE process are slightly higher than the limit in drinking water defined by the U.S. Environmental Protection Agency (EPA) and in effluent at the boundary of an unrestricted area defined by the U.S. Nuclear Regulatory Commission (NRC), respectively. Estimated tritium concentrations in the NGNP using the SI hydrogen production process are significantly higher, and are largely affected by undetermined parameters (i.e., tritium permeability of heat exchanger materials, hydrogen concentration in the helium energy transport fluids, equilibrium constant of the tritium isotope exchange reaction between HT and H{sub 2}SO{sub 4}). These parameters should be measured or estimated in the near future, as should the tritium generation and release rate from the NGNP nuclear reactor core. Decreasing the tritium permeation rate between the primary and secondary heat transport circuits is an effective measure to decrease the tritium concentrations in the …
Date: March 20, 2008
Creator: Sherman, S
Object Type: Article
System: The UNT Digital Library
Real time assessment of RF cardiac tissue ablation with optical spectroscopy (open access)

Real time assessment of RF cardiac tissue ablation with optical spectroscopy

An optical spectroscopy approach is demonstrated allowing for critical parameters during RF ablation of cardiac tissue to be evaluated in real time. The method is based on incorporating in a typical ablation catheter transmitting and receiving fibers that terminate at the tip of the catheter. By analyzing the spectral characteristics of the NIR diffusely reflected light, information is obtained on such parameters as, catheter-tissue proximity, lesion formation, depth of penetration of the lesion, formation of char during the ablation, formation of coagulum around the ablation site, differentiation of ablated from healthy tissue, and recognition of micro-bubble formation in the tissue.
Date: March 20, 2008
Creator: Demos, S G & Sharareh, S
Object Type: Article
System: The UNT Digital Library
Genomic Prospecting for Microbial Biodiesel Production (open access)

Genomic Prospecting for Microbial Biodiesel Production

Biodiesel is defined as fatty acid mono-alkylesters and is produced from triacylglycerols. In the current article we provide an overview of the structure, diversity and regulation of the metabolic pathways leading to intracellular fatty acid and triacylglycerol accumulation in three types of organisms (bacteria, algae and fungi) of potential biotechnological interest and discuss possible intervention points to increase the cellular lipid content. The key steps that regulate carbon allocation and distribution in lipids include the formation of malonyl-CoA, the synthesis of fatty acids and their attachment onto the glycerol backbone, and the formation of triacylglycerols. The lipid biosynthetic genes and pathways are largely known for select model organisms. Comparative genomics allows the examination of these pathways in organisms of biotechnological interest and reveals the evolution of divergent and yet uncharacterized regulatory mechanisms. Utilization of microbial systems for triacylglycerol and fatty acid production is in its infancy; however, genomic information and technologies combined with synthetic biology concepts provide the opportunity to further exploit microbes for the competitive production of biodiesel.
Date: March 20, 2008
Creator: Lykidis, Athanasios; Lykidis, Athanasios & Ivanova, Natalia
Object Type: Book
System: The UNT Digital Library
Corporate Functional Management Evaluation of the LLNL Radiation Safety Organization (open access)

Corporate Functional Management Evaluation of the LLNL Radiation Safety Organization

A Corporate Assess, Improve, and Modernize review was conducted at Lawrence Livermore National Laboratory (LLNL) to evaluate the LLNL Radiation Safety Program and recommend actions to address the conditions identified in the Internal Assessment conducted July 23-25, 2007. This review confirms the findings of the Internal Assessment of the Institutional Radiation Safety Program (RSP) including the noted deficiencies and vulnerabilities to be valid. The actions recommended are a result of interviews with about 35 individuals representing senior management through the technician level. The deficiencies identified in the LLNL Internal Assessment of the Institutional Radiation Safety Program were discussed with Radiation Safety personnel team leads, customers of Radiation Safety Program, DOE Livermore site office, and senior ES&H management. There are significant issues with the RSP. LLNL RSP is not an integrated, cohesive, consistently implemented program with a single authority that has the clear roll and responsibility and authority to assure radiological operations at LLNL are conducted in a safe and compliant manner. There is no institutional commitment to address the deficiencies that are identified in the internal assessment. Some of these deficiencies have been previously identified and corrective actions have not been taken or are ineffective in addressing the issues. Serious …
Date: March 20, 2008
Creator: Sygitowicz, L S
Object Type: Report
System: The UNT Digital Library
Mississippi State Biodiesel Production Project (open access)

Mississippi State Biodiesel Production Project

Biodiesel is a renewable fuel conventionally generated from vegetable oils and animal fats that conforms to ASTM D6751. Depending on the free fatty acid content of the feedstock, biodiesel is produced via transesterification, esterification, or a combination of these processes. Currently the cost of the feedstock accounts for more than 80% of biodiesel production cost. The main goal of this project was to evaluate and develop non-conventional feedstocks and novel processes for producing biodiesel. One of the most novel and promising feedstocks evaluated involves the use of readily available microorganisms as a lipid source. Municipal wastewater treatment facilities (MWWTF) in the USA produce (dry basis) of microbial sludge annually. This sludge is composed of a variety of organisms, which consume organic matter in wastewater. The content of phospholipids in these cells have been estimated at 24% to 25% of dry mass. Since phospholipids can be transesterified they could serve as a ready source of biodiesel. Examination of the various transesterification methods shows that in situ conversion of lipids to FAMEs provides the highest overall yield of biodiesel. If one assumes a 7.0% overall yield of FAMEs from dry sewage sludge on a weight basis, the cost per gallon of extracted …
Date: March 20, 2008
Creator: Hernandez, Rafael; French, Todd; Fernando, Sandun; Li, Tingyu; Braasch, Dwane; Silva, Juan et al.
Object Type: Report
System: The UNT Digital Library
Temperature response of 129Xe depolarization transfer and its application for ultra-sensitive NMR detection (open access)

Temperature response of 129Xe depolarization transfer and its application for ultra-sensitive NMR detection

Temporary trapping of atomic xenon in functionalized cryptophane cages makes the high sensitivity of hyperpolarized (hp) 129Xe available for highly specific NMR detection of biomolecules like proteins in solution. Here, we study the signal transfer onto a reservoir of unbound hp xenon by gating the residence time of the nuclei in the cage through the temperature-dependent exchange rate. Temperature changes were detectable immediately as an altered reservoir signal and yielded a sensitivity of 0.6 K. The temperature response is adjustable with lower concentrations of caged xenon providing more sensitivity at higher temperatures and allows ultra-sensitive detection of such molecular cages at 310 K. Functionalized cryptophane could be detected at concentrations as low as 10nM which corresponds to a 4000-fold sensitivity enhancement compared to conventional detection. This sensitivity makes hp-NMR capable of detecting such constructs in concentrations far belowthe detection limit by UV-visible light absorbance.
Date: March 20, 2008
Creator: Schroeder, Leif; Schroder, Leif; Meldrum, Tyler; Smith, Monica; Lowery, Thomas J.; Wemmer, David E. et al.
Object Type: Article
System: The UNT Digital Library
Reconstruction from Uniformly Attenuated SPECT Projection Data Using the DBH Method (open access)

Reconstruction from Uniformly Attenuated SPECT Projection Data Using the DBH Method

An algorithm was developed for the two-dimensional (2D) reconstruction of truncated and non-truncated uniformly attenuated data acquired from single photon emission computed tomography (SPECT). The algorithm is able to reconstruct data from half-scan (180o) and short-scan (180?+fan angle) acquisitions for parallel- and fan-beam geometries, respectively, as well as data from full-scan (360o) acquisitions. The algorithm is a derivative, backprojection, and Hilbert transform (DBH) method, which involves the backprojection of differentiated projection data followed by an inversion of the finite weighted Hilbert transform. The kernel of the inverse weighted Hilbert transform is solved numerically using matrix inversion. Numerical simulations confirm that the DBH method provides accurate reconstructions from half-scan and short-scan data, even when there is truncation. However, as the attenuation increases, finer data sampling is required.
Date: March 20, 2008
Creator: Huang, Qiu; You, Jiangsheng; Zeng, Gengsheng L. & Gullberg, Grant T.
Object Type: Article
System: The UNT Digital Library
Cable Damage Detection Using Time Domain Reflectometry and Model-Based Algorithms (open access)

Cable Damage Detection Using Time Domain Reflectometry and Model-Based Algorithms

None
Date: March 20, 2008
Creator: Clark, G A
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 39, No. 80, Ed. 1 Thursday, March 20, 2008 (open access)

Greensheet (Houston, Tex.), Vol. 39, No. 80, Ed. 1 Thursday, March 20, 2008

Free weekly newspaper that includes business and classified advertising.
Date: March 20, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 39, No. 81, Ed. 1 Thursday, March 20, 2008 (open access)

Greensheet (Houston, Tex.), Vol. 39, No. 81, Ed. 1 Thursday, March 20, 2008

Free weekly newspaper that includes business and classified advertising.
Date: March 20, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Clean Air Permitting: Status of Implementation and Issues (open access)

Clean Air Permitting: Status of Implementation and Issues

This report describes the statutory background of the Title V program and the status of implementation, in terms of federal approval of state and local permitting authorities and permit issuance. It also discusses broad policy issues identified by various stakeholders, including program complexity and costs, and inconsistencies due to a lack of sufficient federal guidance.
Date: March 20, 2008
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Hydrogen and Fuel Cell Vehicle R&D: FreedomCAR and the President's Hydrogen Fuel Initiative (open access)

Hydrogen and Fuel Cell Vehicle R&D: FreedomCAR and the President's Hydrogen Fuel Initiative

This report discusses the organization, funding, and goals of the FreedomCAR and Fuel partnerships, and issues for Congress.
Date: March 20, 2008
Creator: Yacobucci, Brent D.
Object Type: Report
System: The UNT Digital Library
Texas Jewish Post (Fort Worth, Tex.), Vol. 62, No. 12, Ed. 1 Thursday, March 20, 2008 (open access)

Texas Jewish Post (Fort Worth, Tex.), Vol. 62, No. 12, Ed. 1 Thursday, March 20, 2008

Weekly Jewish newspaper from Fort Worth, Texas that includes local, state and national news along with extensive advertising.
Date: March 20, 2008
Creator: Wisch, Rene
Object Type: Newspaper
System: The Portal to Texas History
The Canadian Record (Canadian, Tex.), Vol. 118, No. 12, Ed. 1 Thursday, March 20, 2008 (open access)

The Canadian Record (Canadian, Tex.), Vol. 118, No. 12, Ed. 1 Thursday, March 20, 2008

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.
Date: March 20, 2008
Creator: Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
The Bastrop Advertiser (Bastrop, Tex.), Vol. 155, No. 7, Ed. 1 Thursday, March 20, 2008 (open access)

The Bastrop Advertiser (Bastrop, Tex.), Vol. 155, No. 7, Ed. 1 Thursday, March 20, 2008

Semi-weekly newspaper from Bastrop, Texas that includes local, state and national news along with advertising.
Date: March 20, 2008
Creator: McAuley, Davis
Object Type: Newspaper
System: The Portal to Texas History
TDNA eBulletin, Volume 1, Issue 3, March 20, 2008 (open access)

TDNA eBulletin, Volume 1, Issue 3, March 20, 2008

Monthly newsletter of the Texas Daily Newspaper Association (TDNA) describing the organization's news and activities as well as other information of interest to readers. This issue includes a summary of the TDNA annual meeting, and an announcement that at President's Dinner on March 10, New Braunfels HeraldZeitung Publisher Doug Toney was named the 2007 Taggart Award winner.
Date: March 20, 2008
Creator: Texas Daily Newspaper Association
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Texas Attorney General Opinion: GA-0610 (open access)

Texas Attorney General Opinion: GA-0610

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification: Whether a state agency must use an average of 100 Mcf per day of natural gas in order to qualify for the exemption provided by section 104.202 of the Utilities Code (RQ-0617-GA)
Date: March 20, 2008
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Stormwater Permits: Status of EPA’s Regulatory Program (open access)

Stormwater Permits: Status of EPA’s Regulatory Program

None
Date: March 20, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The Budget Reconciliation Process: The Senate’s “Byrd Rule” (open access)

The Budget Reconciliation Process: The Senate’s “Byrd Rule”

This report discusses the reconciliation under the congressional budget act of 1974 by which congress implements budget resolution policies affecting mainly permanent spending and revenue programs.
Date: March 20, 2008
Creator: Keith, Robert
Object Type: Report
System: The UNT Digital Library
Overview of the Congressional Budget Process (open access)

Overview of the Congressional Budget Process

None
Date: March 20, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library

[TDNA Linage Report "A," March 2008]

Linage report from March 2008 that details ad revenue from Texas Daily Newspaper Association members.
Date: March 20, 2008
Creator: Texas Daily Newspaper Association
Object Type: Dataset
System: The UNT Digital Library

[TDNA Linage Report "B," February 2008]

Linage report from February 2008 that details ad revenue from Texas Daily Newspaper Association members.
Date: March 20, 2008
Creator: Texas Daily Newspaper Association
Object Type: Dataset
System: The UNT Digital Library

[TDNA Linage Report "A," February 2008]

Linage report from February 2008 that details ad revenue from Texas Daily Newspaper Association members.
Date: March 20, 2008
Creator: Texas Daily Newspaper Association
Object Type: Dataset
System: The UNT Digital Library
Greensheet (Fort Worth, Tex.), Vol. 31, No. 348, Ed. 1 Thursday, March 20, 2008 (open access)

Greensheet (Fort Worth, Tex.), Vol. 31, No. 348, Ed. 1 Thursday, March 20, 2008

Free weekly newspaper that includes business and classified advertising.
Date: March 20, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History