Advanced Water-Gas Shift Membrane Reactor (open access)

Advanced Water-Gas Shift Membrane Reactor

The overall objectives for this project were: (1) to identify a suitable PdCu tri-metallic alloy membrane with high stability and commercially relevant hydrogen permeation in the presence of trace amounts of carbon monoxide and sulfur; and (2) to identify and synthesize a water gas shift catalyst with a high operating life that is sulfur and chlorine tolerant at low concentrations of these impurities. This work successfully achieved the first project objective to identify a suitable PdCu tri-metallic alloy membrane composition, Pd{sub 0.47}Cu{sub 0.52}G5{sub 0.01}, that was selected based on atomistic and thermodynamic modeling alone. The second objective was partially successful in that catalysts were identified and evaluated that can withstand sulfur in high concentrations and at high pressures, but a long operating life was not achieved at the end of the project. From the limited durability testing it appears that the best catalyst, Pt-Re/Ce{sub 0.333}Zr{sub 0.333}E4{sub 0.333}O{sub 2}, is unable to maintain a long operating life at space velocities of 200,000 h{sup -1}. The reasons for the low durability do not appear to be related to the high concentrations of H{sub 2}S, but rather due to the high operating pressure and the influence the pressure has on the WGS reaction …
Date: January 7, 2009
Creator: Emerson, Sean; Vanderspurt, Thomas; Opalka, Susanne; Radhakrishnan, Rakesh & Willigan, Rhonda
Object Type: Report
System: The UNT Digital Library
Final Technical Report - Commercially Important Carbohydrate Diacids - Building Blocks from Renewable Carbohydrates (open access)

Final Technical Report - Commercially Important Carbohydrate Diacids - Building Blocks from Renewable Carbohydrates

The primary objective of this project was to develop oxidation methods appropriate for the conversion of agriculturally derived simple sugars to their corresponding diacids (aldaric acids) for use as biobased chemical building blocks for new biodegradable polymers and other materials. Principal target diacids were D-glucaric, meso-xylaric, D-mannaric and L-arabinaric acid, each to be prepared by nitric acid oxidation of the naturally occurring precursor carbohydrates (monosaccharides) D-glucose, D-xylose, D-mannose and L-arabinose, respectively, all from hydrolysis of naturally abundant plant polysaccharides. These conversions were to be designed for scale up to a level suitable for transfer first to a pilot plant scale, and then to an industrial plant scale. The core of the project involved a comprehensive study of the title oxidation employing a computer controlled reactor. The plan of action involved defining experimental parameters to allow for control of the oxidations with considerable precision and reproducibility. The prototype oxidations were typically run using ca. 0.75 molar amounts of carbohydrate, with a goal of eventually doubling the reaction size when appropriate reaction parameters were established. During the course of the funding period for this grant, the fundamentals of reaction control were established for oxidation of D-glucose, a critical component of the project …
Date: January 7, 2009
Creator: Kiely, Donald E.
Object Type: Report
System: The UNT Digital Library
Weatherization Assistance Program Technical Assistance Center (open access)

Weatherization Assistance Program Technical Assistance Center

The following is a synopsis of the major achievements attributed to the operation of the Weatherization Assistance Program Technical Assistance Center (WAPTAC) by the National Association for State Community Services Programs (NASCSP). During the past five years, the WAPTAC has developed into the premier source for information related to operating the Weatherization Assistance Program (WAP) at the state and local levels. The services provide through WAPTAC include both virtual technical support as well as hands-on training and instruction in classroom and in the field. The WAPTAC achieved several important milestones during its operation including the establishment of a national Weatherization Day now celebrated in most states, the implementation of a comprehensive Public Information Campaign (PIC) to raise the awareness of the Program among policy makers and the public, the training of more than 150 new state managers and staff as they assume their duties in state offices around the country, and the creation and support of a major virtual information source on the Internet being accessed by thousands of staff each month. The Weatherization Assistance Program Technical Assistance Center serves the Department of Energy's (DOE) Office of Weatherization and Intergovernmental Program as a valuable training and technical assistance resource for …
Date: January 7, 2009
Creator: Adams, Robert
Object Type: Report
System: The UNT Digital Library
Technical Report on Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration (open access)

Technical Report on Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration

The Nature Conservancy participated in a Cooperative Agreement with the Department of Energy (DOE) National Energy Technology Laboratory (NETL) to explore the compatibility of carbon sequestration in terrestrial ecosystems and the conservation of biodiversity. The title of the research project was 'Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration'. The objectives of the project were to: (1) improve carbon offset estimates produced in both the planning and implementation phases of projects; (2) build valid and standardized approaches to estimate project carbon benefits at a reasonable cost; and (3) lay the groundwork for implementing cost-effective projects, providing new testing ground for biodiversity protection and restoration projects that store additional atmospheric carbon. This Final Technical Report discusses the results of the six tasks that The Nature Conservancy undertook to answer research needs while facilitating the development of real projects with measurable greenhouse gas reductions. The research described in this report occurred between July 1st 2001 and July 10th 2008. The specific tasks discussed include: Task 1: carbon inventory advancements; Task 2: emerging technologies for remote sensing of terrestrial carbon; Task 3: baseline method development; Task 4: third-party technical advisory panel meetings; Task 5: new project feasibility studies; and …
Date: January 7, 2009
Creator: Stanley, Bill; Brown, Sandra; Kant, Zoe & Gonzalez, Patrick
Object Type: Report
System: The UNT Digital Library
Using Biosurfactants Produced from Agriculture Process Waste Streams to Improve Oil Recovery in Fractured Carbonate Reservoirs (open access)

Using Biosurfactants Produced from Agriculture Process Waste Streams to Improve Oil Recovery in Fractured Carbonate Reservoirs

This report describes the progress of our research during the first 30 months (10/01/2004 to 03/31/2007) of the original three-year project cycle. The project was terminated early due to DOE budget cuts. This was a joint project between the Tertiary Oil Recovery Project (TORP) at the University of Kansas and the Idaho National Laboratory (INL). The objective was to evaluate the use of low-cost biosurfactants produced from agriculture process waste streams to improve oil recovery in fractured carbonate reservoirs through wettability mediation. Biosurfactant for this project was produced using Bacillus subtilis 21332 and purified potato starch as the growth medium. The INL team produced the biosurfactant and characterized it as surfactin. INL supplied surfactin as required for the tests at KU as well as providing other microbiological services. Interfacial tension (IFT) between Soltrol 130 and both potential benchmark chemical surfactants and crude surfactin was measured over a range of concentrations. The performance of the crude surfactin preparation in reducing IFT was greater than any of the synthetic compounds throughout the concentration range studied but at low concentrations, sodium laureth sulfate (SLS) was closest to the surfactin, and was used as the benchmark in subsequent studies. Core characterization was carried out …
Date: January 7, 2009
Creator: Johnson, Stephen; Salehi, Mehdi; Eisert, Karl & Fox, Sandra
Object Type: Report
System: The UNT Digital Library
Demontration of Integrated Optimization Software at the Baldwin Energy Complex (open access)

Demontration of Integrated Optimization Software at the Baldwin Energy Complex

This project encompassed the design, development, and demonstration of integrated online optimization systems at Dynegy Midwest Generation's Baldwin Energy Complex (BEC) located in Baldwin, Illinois. The overall project objective was to improve coal-based generation's emission profile, efficiency, maintenance requirements and plant asset life in order to enhance the long-term viability of the United States abundant coal resources. Five separate but integrated optimization products were developed, addressing combustion, sootblowing, SCR operations, overall unit thermal performance, and plant-wide availability optimization. Optimization results are inherently unit-specific and cannot be known for a particular generating unit in advance. However, NeuCo believed that the following were reasonable targets for the completed, integrated set of products: Furnace NOx reduction improvement by 5%, Heat rate improvement by 1.5%, Increase of annual Available MWh by 1.5%, Commensurate reductions in greenhouse gases, mercury, and particulates; and Commensurate increases in profitability from lower costs, improved reliability, and greater commercial availability. The goal during Phase I was to establish each system and demonstrate their integration in unified plant optimization. Efforts during Phase I focused on: (1) developing, deploying, integrating, and testing prototypes for each of the five products; (2) identifying and addressing issues required for the products to integrate with plant …
Date: January 7, 2009
Creator: James, Rob; McDermott, John; Patnaik, Sanjay & Piche`, Steve
Object Type: Report
System: The UNT Digital Library
A New Concept for the Fabrication of Hydrogen Selective Silica Membranes (open access)

A New Concept for the Fabrication of Hydrogen Selective Silica Membranes

It was proposed to investigate a new concept for the synthesis of molecular sieve hydrogen selective membranes. This concept is based on the use of exfoliated layered zeolite precursors in coating processes to make nanocomposite films with inorganic or polymeric matrices. We discovered that creating exfoliated zeolite layers was much more difficult than anticipated because the methods originally proposed (based on existing literature reports) were not successful in providing exfoliated layers while preserving their porous structure. Although the original goals of fabricating high-selectivity-high-flux membranes that are stable under conditions present in a water-gas-shift reactor and that are able to selectively permeate hydrogen over all other components of the mixtures present in these reactors were not accomplished fully, significant progress has been made as follows: (1) Proof-of-concept hydrogen-selective nanocomposite membranes have been fabricated; (2) Methods to exfoliate layered zeolite precursors preserving the layer structure were identified; and (3) Unexpectedly, membranes exhibiting high ideal selectivity for carbon dioxide over nitrogen at room temperature were produced. The findings listed above provide confidence that the proposed novel concept can eventually be realized.
Date: January 7, 2009
Creator: Tsapatsis, Michael
Object Type: Report
System: The UNT Digital Library
The Resilient Economy: Integrating Competitiveness and Security (open access)

The Resilient Economy: Integrating Competitiveness and Security

Globalization, technological complexity, interdependence, terrorism, climate and energy volatility, and pandemic potential are increasing the level of risk that societies and organizations now face. Risks also are increasingly interrelated; disruptions in one area can cascade in multiple directions. The ability to manage emerging risks, anticipate the interactions between different types of risk, and bounce back from disruption will be a competitive differentiator for companies and countries alike in the 21st century. What Policymakers Should Know The national objective is not just homeland protection, but economic resilience: the ability to mitigate and recover quickly from disruption. Businesses must root the case for investment in resilience strategies to manage a spectrum of risks, not just catastrophic ones. Making a business case for investment in defenses against low-probability events (even those with high impact) is difficult. However, making a business case for investments that assure business continuity and shareholder value is not a heavy lift. There are an infinite number of disruption scenarios, but only a finite number of outcomes. Leading organizations do not manage specific scenarios, rather they create the agility and flexibility to cope with turbulent situations. The investments and contingency plans these leading companies make to manage a spectrum of …
Date: January 7, 2009
Creator: van Opstal, Debbie
Object Type: Report
System: The UNT Digital Library
Field Testing of Activated Carbon Injection Options for Mercury Control at TXU's Big Brown Station (open access)

Field Testing of Activated Carbon Injection Options for Mercury Control at TXU's Big Brown Station

The primary objective of the project was to evaluate the long-term feasibility of using activated carbon injection (ACI) options to effectively reduce mercury emissions from Texas electric generation plants in which a blend of lignite and subbituminous coal is fired. Field testing of ACI options was performed on one-quarter of Unit 2 at TXU's Big Brown Steam Electric Station. Unit 2 has a design output of 600 MW and burns a blend of 70% Texas Gulf Coast lignite and 30% subbituminous Powder River Basin coal. Big Brown employs a COHPAC configuration, i.e., high air-to-cloth baghouses following cold-side electrostatic precipitators (ESPs), for particulate control. When sorbent injection is added between the ESP and the baghouse, the combined technology is referred to as TOXECON{trademark} and is patented by the Electric Power Research Institute in the United States. Key benefits of the TOXECON configuration include better mass transfer characteristics of a fabric filter compared to an ESP for mercury capture and contamination of only a small percentage of the fly ash with AC. The field testing consisted of a baseline sampling period, a parametric screening of three sorbent injection options, and a month long test with a single mercury control technology. During the …
Date: January 7, 2009
Creator: Pavlish, John; Thompson, Jeffrey; Martin, Christopher; Musich, Mark & Hamre, Lucinda
Object Type: Report
System: The UNT Digital Library
Measurement of HOMs in the RHIC RF Cavities (open access)

Measurement of HOMs in the RHIC RF Cavities

The authors present results of Higher Order Modes (HOMs) measurements in the RHIC accelerating (28 MHz system) and storage (197 MHz system) cavities. The power of the excited HOMs deposited into the HOM damper is measured and compared with an analytical calculation of the HOMs power. The quality factors (Q) are also measured and compared to previous measurements.
Date: January 7, 2009
Creator: Abreu,N.P. & Choi, E. M.
Object Type: Report
System: The UNT Digital Library
Design of a rural water provision system to decrease arsenic exposure in Bangladesh (open access)

Design of a rural water provision system to decrease arsenic exposure in Bangladesh

Researchers at the Lawrence Berkeley National Laboratory have invented ARUBA (Arsenic Removal Using Bottom Ash) a material that effectively and affordably removes high concentrations of arsenic from contaminated groundwater. The technology is cost-effective because the substrate?bottom ash from coal fired power plants?is a waste material readily available in South Asia. During fieldwork in four sub-districts ofBangladesh, ARUBA reduced groundwater arsenic concentrations as high as 680 ppb to below the Bangladesh standard of 50 ppb. Key results from three trips in Bangladesh and one trip to Cambodia include (1) ARUBA removes more than half of the arsenic from contaminated water within the first five minutes of contact, andcontinues removing arsenic for 2-3 days; (2) ARUBA?s arsenic removal efficiency can be improved through fractionated dosing (adding a given amount of ARUBA in fractions versus all at once); (3) allowing water to first stand for two to three days followed by treatment with ARUBA produced final arsenic concentrations ten times lower than treating water directly out of the well; and (4) the amount of arsenic removed per gram of ARUBA is linearly related to the initial arsenic concentrationof the water. Through analysis of existing studies, observations, and informal interviews in Bangladesh, eight design …
Date: January 7, 2009
Creator: Mathieu, Johanna
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Mixed-Matric Membranes for CO2 and H2 Gas Separations Using Metal-Organic Framework and Mesoporus Hybrid Silicas (open access)

Mixed-Matric Membranes for CO2 and H2 Gas Separations Using Metal-Organic Framework and Mesoporus Hybrid Silicas

In this work, we have investigated the separation performance of polymer-based mixed-matrix membranes containing metal-organic frameworks and mesoporous hybrid silicas. The MOF/Matrimid{reg_sign} and MOP-18/Matrimid{reg_sign} membranes exhibited improved dispersion and mechanical strength that allowed high additive loadings with reduced aggregation, as is the case of the 80 wt% MOP-18/Matrimid{reg_sign} and the 80% (w/w) Cu-MOF/Matrimid{reg_sign} membranes. Membranes with up to 60% (w/w) ZIF-8 content exhibited similar mechanical strength and improved dispersion. The H{sub 2}/CO{sub 2} separation properties of MOF/Matrimid{reg_sign} mixed-matrix membranes was improved by either keeping the selectivity constant and increasing the permeability (MOF-5, Cu-MOF) or by improving both selectivity and permeability (ZIF-8). In the case of MOF-5/Matrimid{reg_sign} mixed-matrix membranes, the H{sub 2}/CO{sub 2} selectivity was kept at 2.6 and the H{sub 2} permeability increased from 24.4 to 53.8 Barrers. For the Cu-MOF/Matrimid{reg_sign} mixed-matrix membranes, the H{sub 2}/CO{sub 2} selectivity was kept at 2.05 and the H{sub 2} permeability increased from 17.1 to 158 Barrers. These two materials introduced porosity and uniform paths that enhanced the gas transport in the membranes. When ZIF-8/Matrimid{reg_sign} mixed-matrix membranes were studied, the H{sub 2}/CO{sub 2} selectivity increased from 2.9 to 4.4 and the permeability of H{sub 2} increased from 26.5 to 35.8 Barrers. The increased H{sub …
Date: January 7, 2009
Creator: Musselman, Inga; Kenneth Balkus, Jr. & Ferraris, John
Object Type: Report
System: The UNT Digital Library
Causticizing for Black Liquor Gasifiers (open access)

Causticizing for Black Liquor Gasifiers

The cost-benefit outlook of black liquor gasification (BLG) could be greatly improved if the smelt causticization step could be achieved in situ during the gasification step. Or, at a minimum, the increase in causticizing load associated with BLG could be mitigated. A number of chemistries have been proven successful during black liquor combustion. In this project, three in situ causticizing processes (titanate, manganate, and borate) were evaluated under conditions suitable for high temperature entrained flow BLG, and low temperature steam reforming of black liquor. The evaluation included both thermodynamic modeling and lab experimentation. Titanate and manganate were tested for complete direct causticizing (to thus eliminate the lime cycle), and borates were evaluated for partial causticizing (to mitigate the load increase associated with BLG). Criteria included high carbonate conversion, corresponding hydroxide recovery upon hydrolysis, non process element (NPE) removal, and economics. Of the six cases (three chemistries at two BLG conditions), only two were found to be industrially viable: titanates for complete causticizing during high temperature BLG, and borates for partial causticizing during high temperature BLG. These two cases were evaluated for integration into a gasification-based recovery island. The Larsen [28] BLG cost-benefit study was used as a reference case for …
Date: January 7, 2009
Creator: Sinquefeld, Scott; Cantrell, James; Zeng, Xiaoyan; Ball, Alan & Empie, Jeff
Object Type: Report
System: The UNT Digital Library
Health Effects of Subchronic Inhalation of Simulated Downwind Coal Combustion Emissions (open access)

Health Effects of Subchronic Inhalation of Simulated Downwind Coal Combustion Emissions

The purpose of this project was to conduct a comprehensive laboratory-based evaluation of selected respiratory and cardiac health hazards of subchronic (up to 6 months) inhalation of simulated key components of 'downwind plume' emissions of coal combustion. This project was performed as an integral part of a joint government-industry program termed the 'National Environmental Respiratory Center' (NERC), which is aimed at disentangling the roles of different physical-chemical air pollutants and their sources in the health effects associated statistically with air pollution. The characterization of the exposure atmosphere and the health assays were identical to those employed in the NERC protocols used to evaluate other pollution source emissions, such as diesel, gasoline, and wood combustion. The project had two phases, each encompassing multiple tasks. Guidelines for the composition of the exposure atmosphere were set by consensus of an expert workshop. Development of the capability to generate the exposure atmosphere and pilot studies of the comparative exposure composition using two coal types were accomplished in Phase 1. In Phase 2, the toxicological study was conducted using Powder River Basin Sub-bituminous coal. NETL provided 50% support for the work in Phase 1 and had intended to provide 20% support for the work in …
Date: January 7, 2009
Creator: Mauderly, Joe
Object Type: Report
System: The UNT Digital Library
Research and Development of a New Field Enhanced Low Temperature Thermionic Cathode that Enables Fluorescent Dimming and Loan Shedding without Auxiliary Cathode Heating (open access)

Research and Development of a New Field Enhanced Low Temperature Thermionic Cathode that Enables Fluorescent Dimming and Loan Shedding without Auxiliary Cathode Heating

This is the final report for project entitled 'Research and development of a new field enhanced low temperature thermionic cathode that enables fluorescent dimming and load shedding without auxiliary cathode heating', under Agreement Number: DE-FC26-04NT-42329. Under this project, a highly efficient CNT based thermionic cathode was demonstrated. This cathode is capable of emitting electron at a current density two order of magnitude stronger then a typical fluorescent cathode at same temperatures, or capable of emitting at same current density but at temperature about 300 C lower than that of a fluorescent cathode. Detailed fabrication techniques were developed including CVD growth of CNTs and sputter deposition of oxide thin films on CNTs. These are mature technologies that have been widely used in industry for large scale materials processing and device fabrications, thus, with further development work, the techniques developed in this project can be scaled-up in manufacturing environment. The prototype cathodes developed in this project were tested in lighting plasma discharge environment. In many cases, they not only lit and sustain the plasma, but also out perform the fluorescent cathodes in key parameters such like cathode fall voltages. More work will be needed to further evaluate more detailed and longer term …
Date: January 7, 2009
Creator: Jin, Feng
Object Type: Report
System: The UNT Digital Library
UTILIZING INNOVATIVE TECHNOLOGIES FOR ENVIRONMENTAL CLEAN-UP, SAVAHHAH RIVER SITE (open access)

UTILIZING INNOVATIVE TECHNOLOGIES FOR ENVIRONMENTAL CLEAN-UP, SAVAHHAH RIVER SITE

The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River near Aiken, South Carolina. During operations, which started in 1951, hazardous substances (chemicals and radionuclides) were released to the environment. The releases occurred as a result of inadvertent spills and waste disposal in unlined pits and basins which was common practice before environmental regulations existed. The hazardous substances have migrated to the vadose zone and groundwater in many areas of the SRS, resulting in 515 waste units and facilities that are required by environmental regulations, to undergo characterization and, if needed, remediation. In the initial years of the SRS environmental cleanup program (early 1990s), the focus was to use common technologies (such as pump and treat, air stripping, excavation and removal) that actively and tangibly removed contamination. Exclusive use of these technologies required continued and significant funding while often failing to meet acceptable clean-up goals and objectives. Recognizing that a more cost-effective approach was needed, SRS implemented new and complementary remediation methods focused on active and passive technologies targeted to solve specific remediation problems. Today, SRS uses technologies such as chemical/pH-adjusting injection, phytoremediation, underground cutoff walls, dynamic underground stripping, soil …
Date: January 7, 2009
Creator: Bergren, C
Object Type: Article
System: The UNT Digital Library
Combined Theoretical and Experimental Investigation and Design of H2S Tolerant Anode for Solid Oxide Fuel Cells (open access)

Combined Theoretical and Experimental Investigation and Design of H2S Tolerant Anode for Solid Oxide Fuel Cells

A solid oxide fuel cell (SOFC) is a high temperature fuel cell and it normally operates in the range of 850 to 1000 C. Coal syngas has been considered for use in SOFC systems to produce electric power, due to its high temperature and high hydrogen and carbon monoxide content. However, coal syngas also has contaminants like carbon dioxide (CO{sub 2}) and hydrogen sulfide (H{sub 2}S). Among these contaminants, H{sub 2}S is detrimental to electrode material in SOFC. Commonly used anode material in SOFC system is nickel-yttria stabilized zirconia (Ni-YSZ). The presence of H{sub 2}S in the hydrogen stream will damage the Ni anode and hinder the performance of SOFC. In the present study, an attempt was made to understand the mechanism of anode (Ni-YSZ) deterioration by H{sub 2}S. The study used computation methods such as quantum chemistry calculations and molecular dynamics to predict the model for anode destruction by H{sub 2}S. This was done using binding energies to predict the thermodynamics and Raman spectroscopy to predict molecular vibrations and surface interactions. On the experimental side, a test stand has been built with the ability to analyze button cells at high temperature under syngas conditions.
Date: January 7, 2009
Creator: Botte, Gerardine G.; Daramola, Damilola & Muthuvel, Madhivanan
Object Type: Report
System: The UNT Digital Library
Radiosensitivity profiles from a panel of ovarian cancer cell lines exhibiting genetic alterations in p53 and disparate DNA-dependent protein kinase activities (open access)

Radiosensitivity profiles from a panel of ovarian cancer cell lines exhibiting genetic alterations in p53 and disparate DNA-dependent protein kinase activities

The variability of radiation responses in ovarian tumors and tumor-derived cell lines is poorly understood. Since both DNA repair capacity and p53 status can significantly alter radiation sensitivity, we evaluated these factors along with radiation sensitivity in a panel of sporadic human ovarian carcinoma cell lines. We observed a gradation of radiation sensitivity among these sixteen lines, with a five-fold difference in the LD50 between the most radiosensitive and the most radioresistant cells. The DNA-dependent protein kinase (DNA-PK) is essential for the repair of radiation induced DNA double-strand breaks in human somatic cells. Therefore, we measured gene copy number, expression levels, protein abundance, genomic copy and kinase activity for DNA-PK in all of our cell lines. While there were detectable differences in DNA-PK between the cell lines, there was no clear correlation with any of these differences and radiation sensitivity. In contrast, p53 function as determined by two independent methods, correlated well with radiation sensitivity, indicating p53 mutant ovarian cancer cells are typically radioresistant relative to p53 wild-type lines. These data suggest that the activity of regulatory molecules such as p53 may be better indicators of radiation sensitivity than DNA repair enzymes such as DNAPK in ovarian cancer.
Date: September 7, 2009
Creator: Langland, Gregory T.; Yannone, Steven M.; Langland, Rachel A.; Nakao, Aki; Guan, Yinghui; Long, Sydney B.T. et al.
Object Type: Article
System: The UNT Digital Library
Materials Science and Physics at Micro/Nano-Scales. FINAL REPORT (open access)

Materials Science and Physics at Micro/Nano-Scales. FINAL REPORT

The scope of this project is to study nanostructures of semiconductors and superconductors, which have been regarded as promising building blocks for nanoelectronic and nanoelectric devices. The emphasis of this project is on developing novel synthesis approaches for fabrication of nanostructures with desired physical properties. The ultimate goal is to achieve a full control of the nanostructure growth at microscopic scales. The major experimental achievements obtained are summarized
Date: September 7, 2009
Creator: Wu, Judy Z.
Object Type: Report
System: The UNT Digital Library
13.2 nm Table-Top Inspection Microscope for Extreme Ultraviolet Lithography Mask Defect Characterization (open access)

13.2 nm Table-Top Inspection Microscope for Extreme Ultraviolet Lithography Mask Defect Characterization

We report on a reflection microscope that operates at 13.2-nm wavelength with a spatial resolution of 55{+-}3 nm. The microscope uses a table-top EUV laser to acquire images of photolithography masks in 20 seconds.
Date: April 7, 2009
Creator: Brizuela, F.; Wang, Y.; Brewer, C.; Pedaci, F.; Chao, W.; Anderson, E. et al.
Object Type: Article
System: The UNT Digital Library
Toward Photochemical Water Splitting Using Band-Gap-Narrowed Semiconductors and Transition-Metal Based Molecular Catalysts (open access)

Toward Photochemical Water Splitting Using Band-Gap-Narrowed Semiconductors and Transition-Metal Based Molecular Catalysts

We are carrying out coordinated theoretical and experimental studies of toward photochemical water splitting using band-gap-narrowed semiconductors (BGNSCs) with attached multi-electron molecular water oxidation and hydrogen production catalysts. We focus on the coupling between the materials properties and the H{sub 2}O redox chemistry, with an emphasis on attaining a fundamental understanding of the individual elementary steps in the following four processes: (1) Light-harvesting and charge-separation of stable oxide or oxide-derived semiconductors for solar-driven water splitting, including the discovery and characterization of the behavior of such materials at the aqueous interface; (2) The catalysis of the four-electron water oxidation by dinuclear hydroxo transition-metal complexes with quinonoid ligands, and the rational search for improved catalysts; (3) Transfer of the design principles learned from the elucidation of the DuBois-type hydrogenase model catalysts in acetonitrile to the rational design of two-electron hydrogen production catalysts for aqueous solution; (4) Combining these three elements to examine the function of oxidation catalysts on BGNSC photoanode surfaces and hydrogen production catalysts on cathode surfaces at the aqueous interface to understand the challenges to the efficient coupling of the materials functions.
Date: June 7, 2009
Creator: Muckerman, J. T.; Rodriguez, J. A. & Fujita, E.
Object Type: Article
System: The UNT Digital Library
Surveillance of Site A and Plot M, Report for 2008. (open access)

Surveillance of Site A and Plot M, Report for 2008.

The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for Calendar Year 2008 are presented. Based on the results of the 1976-1978 radiological characterization of the site, a determination was made that a surveillance program be established. The characterization study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby hand pumped picnic wells. The current surveillance program began in 1980 and consists of sample collection and analysis of surface and subsurface water. The results of the analyses are used to (1) monitor the migration pathway of hydrogen-3 contaminated water from the burial ground (Plot M) to the hand-pumped picnic wells, (2) establish if other buried radionuclides have migrated, and (3) monitor for the presence of radioactive materials in the environment of the area. Hydrogen-3 in the Red Gate Woods picnic wells was still detected this year, but the average and maximum concentrations were significantly less than found earlier. Hydrogen-3 continues to be detected in a number of wells, boreholes, dolomite holes, and a surface stream. Analyses since 1984 have indicated the presence of low levels of strontium-90 in …
Date: May 7, 2009
Creator: Golchert, N. W.
Object Type: Report
System: The UNT Digital Library
Measurements of CKM angles beta/phi_1 and alpha/phi_2 at the Babar and Belle experiments. (open access)

Measurements of CKM angles beta/phi_1 and alpha/phi_2 at the Babar and Belle experiments.

We report measurements of the CKM angles {beta}/{phi}{sub 1} and {alpha}/{phi}{sub 2} done by the BABAR and Belle experiments. Both experiments have collected large data samples, corresponding to a total of more than 1 billion of B{bar B} pairs, at the e{sup +}e{sup -} asymmetric-energy colliders PEP-II (SLAC) and KEK-B (KEK), respectively.
Date: May 7, 2009
Creator: Lazzaro, A.
Object Type: Article
System: The UNT Digital Library
"Data Acquisition Systems" (open access)

"Data Acquisition Systems"

This project involved support for Lou Costrell and myself in the development of IEEE and IEC standards for nuclear counting and data acquisition systems. Over the years, as a result of this support, Lou and I were able to attend standards meetings of IEEE and IEC, which led directly to the publication of many standards for NIM systems, FastBus and CAMAC. We also chaired several writing committees as well as ANSI N42 (Nuclear instrumentation), IEEE NIM (NIM standard), IEEE NID (NPSS nuclear instruments and detector) and IEC TC45 WG9 (Nuclear instrumentation). Through this support we were able to assure that the interests of the US and DOE were expressed and implemented in the various standards.
Date: July 7, 2009
Creator: Unterweger, Michael & Costrell, Louis deceased
Object Type: Report
System: The UNT Digital Library