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Novel Sorbent-Based Process for High Temperature Trace Metal Removal (open access)

Novel Sorbent-Based Process for High Temperature Trace Metal Removal

The objective of this project was to demonstrate the efficacy of a novel sorbent can effectively remove trace metal contaminants (Hg, As, Se and Cd) from actual coal-derived synthesis gas streams at high temperature (above the dew point of the gas). The performance of TDA's sorbent has been evaluated in several field demonstrations using synthesis gas generated by laboratory and pilot-scale coal gasifiers in a state-of-the-art test skid that houses the absorbent and all auxiliary equipment for monitoring and data logging of critical operating parameters. The test skid was originally designed to treat 10,000 SCFH gas at 250 psig and 350 C, however, because of the limited gas handling capabilities of the test sites, the capacity was downsized to 500 SCFH gas flow. As part of the test program, we carried out four demonstrations at two different sites using the synthesis gas generated by the gasification of various lignites and a bituminous coal. Two of these tests were conducted at the Power Systems Demonstration Facility (PSDF) in Wilsonville, Alabama; a Falkirk (North Dakota) lignite and a high sodium lignite (the PSDF operator Southern Company did not disclose the source of this lignite) were used as the feedstock. We also carried …
Date: September 30, 2008
Creator: Alptekin, Gokhan
Object Type: Report
System: The UNT Digital Library
Hybrid Combustion-Gasification Chemical Looping: Coal Power Development Phase III -- Final Report (open access)

Hybrid Combustion-Gasification Chemical Looping: Coal Power Development Phase III -- Final Report

For the past several years Alstom Power Inc. (Alstom), a leading world-wide power system manufacturer and supplier, has been in the initial stages of developing an entirely new, ultra-clean, low cost, high efficiency power plant for the global power market. This new power plant concept is based on a hybrid combustion-gasification process utilizing high temperature chemical and thermal looping technology The process consists of the oxidation, reduction, carbonation, and calcination of calcium-based compounds, which chemically react with coal, biomass, or opportunity fuels in two chemical loops and one thermal loop. The chemical and thermal looping technology can be alternatively configured as (i) a combustion-based steam power plant with CO{sub 2} capture, (ii) a hybrid combustion-gasification process producing a syngas for gas turbines or fuel cells, or (iii) an integrated hybrid combustion-gasification process producing hydrogen for gas turbines, fuel cells or other hydrogen based applications while also producing a separate stream of CO{sub 2} for use or sequestration. In its most advanced configuration, this new concept offers the promise to become the technology link from today's Rankine cycle steam power plants to tomorrow's advanced energy plants. The objective of this work is to develop and verify the high temperature chemical and …
Date: September 30, 2008
Creator: Andrus, Herbert; Burns, Gregory; Chiu, John; Lijedahl, Gregory; Stromberg, Peter & Thibeault, Paul
Object Type: Report
System: The UNT Digital Library
Demonstrating the Model Nature of the High-Temperature Superconductor HgBa2CuO4+d (open access)

Demonstrating the Model Nature of the High-Temperature Superconductor HgBa2CuO4+d

The compound HgBa{sub 2}CuO{sub 4+{delta}} (Hg1201) exhibits a simple tetragonal crystal structure and the highest superconducting transition temperature (T{sub c}) among all single Cu-O layer cuprates, with T{sub c} = 97 K (onset) at optimal doping. Due to a lack of sizable single crystals, experimental work on this very attractive system has been significantly limited. Thanks to a recent breakthrough in crystal growth, such crystals have now become available. Here, we demonstrate that it is possible to identify suitable heat treatment conditions to systematically and uniformly tune the hole concentration of Hg1201 crystals over a wide range, from very underdoped (T{sub c} = 47 K, hole concentration p {approx} 0.08) to overdoped (T{sub c} = 64 K, p {approx} 0.22). We then present quantitative magnetic susceptibility and DC charge transport results that reveal the very high-quality nature of the studied crystals. Using XPS on cleaved samples, we furthermore demonstrate that it is possible to obtain large surfaces of good quality. These characterization measurements demonstrate that Hg1201 should be viewed as a model high-temperature superconductor, and they provide the foundation for extensive future experimental work.
Date: September 30, 2008
Creator: Barisic, Neven; Li, Yuan; Zhao, Xudong; Cho, Yong-Chan; Chabot-Couture, Guillaume; Yu, Guichuan et al.
Object Type: Article
System: The UNT Digital Library
Evaluation of Phytoremediation of Coal Bed Methane Product Water and Waters of Quality Similar to that Associated with Coal Bed Methane Reserves of the Powder River Basin, Montana and Wyoming (open access)

Evaluation of Phytoremediation of Coal Bed Methane Product Water and Waters of Quality Similar to that Associated with Coal Bed Methane Reserves of the Powder River Basin, Montana and Wyoming

U.S. emphasis on domestic energy independence, along with advances in knowledge of vast biogenically sourced coalbed methane reserves at relatively shallow sub-surface depths with the Powder River Basin, has resulted in rapid expansion of the coalbed methane industry in Wyoming and Montana. Techniques have recently been developed which constitute relatively efficient drilling and methane gas recovery and extraction techniques. However, this relatively efficient recovery requires aggressive reduction of hydrostatic pressure within water-saturated coal formations where the methane is trapped. Water removed from the coal formation during pumping is typically moderately saline and sodium-bicarbonate rich, and managed as an industrial waste product. Current approaches to coalbed methane product water management include: surface spreading on rangeland landscapes, managed irrigation of agricultural crop lands, direct discharge to ephermeral channels, permitted discharge of treated and untreated water to perennial streams, evaporation, subsurface injection at either shallow or deep depths. A Department of Energy-National Energy Technology Laboratory funded research award involved the investigation and assessment of: (1) phytoremediation as a water management technique for waste water produced in association with coalbed methane gas extraction; (2) feasibility of commercial-scale, low-impact industrial water treatment technologies for the reduction of salinity and sodicity in coalbed methane gas extraction …
Date: September 30, 2008
Creator: Bauder, James
Object Type: Report
System: The UNT Digital Library
Horse Slaughter Prevention Bills and Issues (open access)

Horse Slaughter Prevention Bills and Issues

In 2006 two Texas plants and one in Illinois slaughtered nearly 105,000 horses for human food, mainly for European and Asian consumers. In 2007, court action effectively closed the Texas plants, and a new state ban in Illinois closed the plant. Meanwhile, activists have continued to press for legislative bans appropriated funds and user fees for inspection of horses for human food.
Date: September 30, 2008
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
Hydrogen-Assisted IC Engine Combustion as a Route to Hydrogen Implementation (open access)

Hydrogen-Assisted IC Engine Combustion as a Route to Hydrogen Implementation

The 'Freedom Car' Initiative announced by the Bush Administration has placed a significant emphasis on development of a hydrogen economy in the United States. While the hydrogen-fueled fuel-cell vehicle that is the focus of the 'Freedom Car' program would rely on electrochemical energy conversion, and despite the large amount of resources being devoted to its objectives, near-term implementation of hydrogen in the transportation sector is not likely to arise from fuel cell cars. Instead, fuel blending and ''hydrogen-assisted'' combustion are more realizable pathways for wide-scale hydrogen utilization within the next ten years. Thus, a large potential avenue for utilization of hydrogen in transportation applications is through blending with natural gas, since there is an existing market for natural-gas vehicles of various classes, and since hydrogen can provide a means of achieving even stricter emissions standards. Another potential avenue is through use of hydrogen to 'assist' diesel combustion to permit alternate combustion strategies that can achieve lower emissions and higher efficiency. This project focused on developing the underlying fundamental information to support technologies that will facilitate the introduction of coal-derived hydrogen into the market. Two paths were envisioned for hydrogen utilization in transportation applications. One is for hydrogen to be mixed …
Date: September 30, 2008
Creator: Boehman, Andre & Haworth, Daniel
Object Type: Report
System: The UNT Digital Library
Uranium Contamination in the 300 Area: Emergent Data and their Impact on the Source Term Conceptual Model (open access)

Uranium Contamination in the 300 Area: Emergent Data and their Impact on the Source Term Conceptual Model

The primary objectives of this characterization activity were to: 1) determine the extent of uranium contamination in the sediments, 2) quantify the leachable (labile) concentration of uranium in the sediments, and 3) create a data set that could be used to correlate the present data to existing 300 Area data. In order to meet these objectives, sediments collected from wells 399-2-5 (C5708), 299-3-22 (C5706) and 299-4-14 (C5707) were analyzed for moisture content, 1:1 sediment:water extracts (which provide soil pH, electrical conductivity [EC], cation, and anion data), total carbon and inorganic carbon content, 8 M nitric acid extracts (which provide a measure of the total leachable sediment content of the contaminants), microwave-assisted digestion (which results in total digestion of the sediment), and carbonate leaches (which provide an assessment of the concentration of labile uranium present in the sediments). Additionally, pore waters present in select samples were extracted using ultracentrifugation. The mobility characteristics of uranium vary within the multiple subsurface zones that contain residual contaminant uranium. Principal subsurface zones include 1) the vadose zone, 2) a zone through which the water table rises and falls, 3) the aquifer, and 4) a zone where groundwater and river water interact beneath the river shoreline. …
Date: September 30, 2008
Creator: Brown, Christopher F.; Um, Wooyong & Serne, R. Jeffrey
Object Type: Report
System: The UNT Digital Library
Perry Daily Journal (Perry, Okla.), Vol. 116, No. 193, Ed. 1 Tuesday, September 30, 2008 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 116, No. 193, Ed. 1 Tuesday, September 30, 2008

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: September 30, 2008
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
U.S. Building-Sector Energy Efficiency Potential (open access)

U.S. Building-Sector Energy Efficiency Potential

This paper presents an estimate of the potential for energy efficiency improvements in the U.S. building sector by 2030. The analysis uses the Energy Information Administration's AEO 2007 Reference Case as a business-as-usual (BAU) scenario, and applies percentage savings estimates by end use drawn from several prior efficiency potential studies. These prior studies include the U.S. Department of Energy's Scenarios for a Clean Energy Future (CEF) study and a recent study of natural gas savings potential in New York state. For a few end uses for which savings estimates are not readily available, the LBNL study team compiled technical data to estimate savings percentages and costs of conserved energy. The analysis shows that for electricity use in buildings, approximately one-third of the BAU consumption can be saved at a cost of conserved energy of 2.7 cents/kWh (all values in 2007 dollars), while for natural gas approximately the same percentage savings is possible at a cost of between 2.5 and 6.9 $/million Btu. This cost-effective level of savings results in national annual energy bill savings in 2030 of nearly $170 billion. To achieve these savings, the cumulative capital investment needed between 2010 and 2030 is about $440 billion, which translates to …
Date: September 30, 2008
Creator: Brown, Rich; Borgeson, Sam; Koomey, Jon & Biermayer, Peter
Object Type: Report
System: The UNT Digital Library
Mechanistic Understanding of Microbial Plugging for Improved Sweep Efficiency (open access)

Mechanistic Understanding of Microbial Plugging for Improved Sweep Efficiency

Microbial plugging has been proposed as an effective low cost method of permeability reduction. Yet there is a dearth of information on the fundamental processes of microbial growth in porous media, and there are no suitable data to model the process of microbial plugging as it relates to sweep efficiency. To optimize the field implementation, better mechanistic and volumetric understanding of biofilm growth within a porous medium is needed. In particular, the engineering design hinges upon a quantitative relationship between amount of nutrient consumption, amount of growth, and degree of permeability reduction. In this project experiments were conducted to obtain new data to elucidate this relationship. Experiments in heterogeneous (layered) beadpacks showed that microbes could grow preferentially in the high permeability layer. Ultimately this caused flow to be equally divided between high and low permeability layers, precisely the behavior needed for MEOR. Remarkably, classical models of microbial nutrient uptake in batch experiments do not explain the nutrient consumption by the same microbes in flow experiments. We propose a simple extension of classical kinetics to account for the self-limiting consumption of nutrient observed in our experiments, and we outline a modeling approach based on architecture and behavior of biofilms. Such a …
Date: September 30, 2008
Creator: Bryant, Steven & Britton, Larry
Object Type: Report
System: The UNT Digital Library
Origin of Scale-Dependent Dispersivity and Its Implications For Miscible Gas Flooding (open access)

Origin of Scale-Dependent Dispersivity and Its Implications For Miscible Gas Flooding

Dispersive mixing has an important impact on the effectiveness of miscible floods. Simulations routinely assume Fickian dispersion, yet it is well established that dispersivity depends on the scale of measurement. This is one of the main reasons that a satisfactory method for design of field-scale miscible displacement processes is still not available. The main objective of this project was to improve the understanding of the fundamental mechanisms of dispersion and mixing, particularly at the pore scale. To this end, microsensors were developed and used in the laboratory to measure directly the solute concentrations at the scale of individual pores; the origin of hydrodynamic dispersion was evaluated from first principles of laminar flow and diffusion at the grain scale in simple but geometrically completely defined porous media; techniques to use flow reversal to distinguish the contribution to dispersion of convective spreading from that of true mixing; and the field scale impact of permeability heterogeneity on hydrodynamic dispersion was evaluated numerically. This project solved a long-standing problem in solute transport in porous media by quantifying the physical basis for the scaling of dispersion coefficient with the 1.2 power of flow velocity. The researchers also demonstrated that flow reversal uniquely enables a crucial …
Date: September 30, 2008
Creator: Bryant, Steven; Johns, Russ; Lake, Larry & Harmon, Thomas
Object Type: Report
System: The UNT Digital Library
FINAL TECHNICAL REPORT FOR DE-FG02-05ER64097 Systems and Methods for Injecting Helium Beams into a Synchrotron Accelerator (open access)

FINAL TECHNICAL REPORT FOR DE-FG02-05ER64097 Systems and Methods for Injecting Helium Beams into a Synchrotron Accelerator

A research grant was approved to fund development of requirements and concepts for extracting a helium-ion beam at the LLUMC proton accelerator facility, thus enabling the facility to better simulate the deep space environment via beams sufficient to study biological effects of accelerated helium ions in living tissues. A biologically meaningful helium-ion beam will be accomplished by implementing enhancements to increase the accelerator’s maximum proton beam energy output from 250MeV to 300MeV. Additional benefits anticipated from the increased energy include the capability to compare possible benefits from helium-beam radiation treatment with proton-beam treatment, and to provide a platform for developing a future proton computed tomography imaging system.
Date: September 30, 2008
Creator: Bush, David A
Object Type: Report
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 110, No. 49, Ed. 1 Tuesday, September 30, 2008 (open access)

The Altus Times (Altus, Okla.), Vol. 110, No. 49, Ed. 1 Tuesday, September 30, 2008

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: September 30, 2008
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Magnetic domains and surface effects in hollow maghemite nanoparticles (open access)

Magnetic domains and surface effects in hollow maghemite nanoparticles

In the present work, we investigate the magnetic properties of ferrimagnetic and non-interacting maghemite hollow nanoparticles obtained by the Kirkendall effect. From the experimental characterization of their magnetic behavior, we find that polycrystalline hollow maghemite nanoparticles exhibit low blocked-to-superparamagnetic transition temperatures, small magnetic moments, significant coercivities and irreversibility fields, and no magnetic saturation on external magnetic fields up to 5 T. These results are interpreted in terms of the microstructural parameters characterizing the maghemite shells by means of atomistic Monte Carlo simulations of an individual spherical shell. The model comprises strongly interacting crystallographic domains arranged in a spherical shell with random orientations and anisotropy axis. The Monte Carlo simulation allows discernment between the influence of the polycrystalline structure and its hollow geometry, while revealing the magnetic domain arranggement in the different temperataure regimes.
Date: September 30, 2008
Creator: Cabot, Andreu; Alivisatos, A. Paul; Puntes, Victor; Balcells, Lluis; Iglesias, Oscar & Labarta, Amilcar
Object Type: Article
System: The UNT Digital Library
The Boerne Star (Boerne, Tex.), Vol. 102, No. 79, Ed. 1 Tuesday, September 30, 2008 (open access)

The Boerne Star (Boerne, Tex.), Vol. 102, No. 79, Ed. 1 Tuesday, September 30, 2008

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: September 30, 2008
Creator: Cartwright, Brian
Object Type: Newspaper
System: The Portal to Texas History
The Mississippian Leadville Limestone Exploration Play, Utah and Colorado-Exploration Techniques and Studies for Independents (open access)

The Mississippian Leadville Limestone Exploration Play, Utah and Colorado-Exploration Techniques and Studies for Independents

The Mississippian (late Kinderhookian to early Meramecian) Leadville Limestone is a shallow, open-marine, carbonate-shelf deposit. The Leadville has produced over 53 million barrels (8.4 million m{sup 3}) of oil/condensate from seven fields in the Paradox fold and fault belt of the Paradox Basin, Utah and Colorado. The environmentally sensitive, 7500-square-mile (19,400 km{sup 2}) area that makes up the fold and fault belt is relatively unexplored. Only independent producers operate and continue to hunt for Leadville oil targets in the region. The overall goal of this study is to assist these independents by (1) developing and demonstrating techniques and exploration methods never tried on the Leadville Limestone, (2) targeting areas for exploration, (3) increasing deliverability from new and old Leadville fields through detailed reservoir characterization, (4) reducing exploration costs and risk especially in environmentally sensitive areas, and (5) adding new oil discoveries and reserves. The final results will hopefully reduce exploration costs and risks, especially in environmentally sensitive areas, and add new oil discoveries and reserves. The study consists of three sections: (1) description of lithofacies and diagenetic history of the Leadville at Lisbon field, San Juan County, Utah, (2) methodology and results of a surface geochemical survey conducted over the …
Date: September 30, 2008
Creator: Chidsey, Thomas
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 88, No. 272, Ed. 1 Tuesday, September 30, 2008 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 88, No. 272, Ed. 1 Tuesday, September 30, 2008

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: September 30, 2008
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Top quark physics expectations at the LHC (open access)

Top quark physics expectations at the LHC

The top quark will be produced copiously at the LHC. This will make possible detailed physics studies, and also the use of top quark decays for detector calibration. This talk reviews plans and prospects for top physics activities in ATLAS and CMS experiments.
Date: September 30, 2008
Creator: Collaboration, ATLAS; Collaboration, CMS & Gaponenko, Andrei
Object Type: Article
System: The UNT Digital Library
Engage States on Energy Assurance and Energy Security (open access)

Engage States on Energy Assurance and Energy Security

The NGA Center's 'Engaging States on Energy Security and Energy Assurance' has been successful in achieving the stated project purposes and objectives both in the initial proposal as well as in subsequent revisions to it. Our activities, which involve the NGA Center for Best Practices (The NGA Center) Homeland Security and Technology Division, included conducting tabletop exercises to help federal and state homeland security and energy officials determine roles and actions for various emergency scenarios. This included efforts to education state official on developing an energy assurance plan, harmonizing approaches to controlling price volatility, implementing reliability standards, understanding short and long-term energy outlooks and fuel diversification, and capitalizing on DOE's research and development activities. Regarding our work on energy efficiency and renewable energy, the NGA Center's Environment, Energy and Natural Resources Division hosted three workshops which engaged states on the clean energy and alternative transportation fuel and also produced several reports on related topics. In addition, we convened 18 meetings, via conference call, of the Energy Working Group. Finally, through the NGA Center's Front and Center newsletter articles, the NGA Center disseminated promising practices to a wide audience of state policymakers. The NGA Center also hosted a number of workshops …
Date: September 30, 2008
Creator: Colton, Kara; Ratliff, John; Gander, Sue; Springer, Darren & Dierkers, Greg
Object Type: Report
System: The UNT Digital Library
Assessment of Technetium Leachability in Cement Stabilized Basin 43 Groundwater Brine (open access)

Assessment of Technetium Leachability in Cement Stabilized Basin 43 Groundwater Brine

This report is an initial report on the laboratory effort executed under RPP-PLAN-33338, Test Plan for the Assessment of Technetium Leachability in Cement-Stabilized Basin 43 Groundwater Brine. This report delineates preliminary data obtained under subcontract 21065, release 30, from the RJ Lee Group, Inc., Center for Laboratory Sciences. The report is predicated on CLS RPT-816, Draft Report: Assessment of Technetium Leachability in Cement Stabilized Basin 43 Groundwater Brine. This document will be revised on receipt of the final RJ Lee Group, Inc., Center for Laboratory Sciences report, which will contain data subjected to quality control and quality assurance criteria.
Date: September 30, 2008
Creator: Cooke, G. A.; Duncan, J. B. & Lockrem, L. L.
Object Type: Report
System: The UNT Digital Library
Air Quality Issues and Animal Agriculture: EPA’s Air Compliance Agreement (open access)

Air Quality Issues and Animal Agriculture: EPA’s Air Compliance Agreement

This report discusses a plan announced by EPA in January 2005, called the Air Compliance Agreement, intended to produce air quality monitoring data on animal agriculture emissions from a small number of farms, while at the same time protecting all participants (including farms where no monitoring takes place) through a “safe harbor” from liability under certain provisions of federal environmental laws.
Date: September 30, 2008
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Animal Waste and Hazardous Substances: Current Laws and Legislative Issues (open access)

Animal Waste and Hazardous Substances: Current Laws and Legislative Issues

This report is about the animal sector of agriculture and rise of concerns over the management of animal wastes and potential impacts on environmental quality.
Date: September 30, 2008
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
The Federal Workforce: Characteristics and Trends (open access)

The Federal Workforce: Characteristics and Trends

This report discusses the federal workforce, which is also expected by some to reflect the gender, racial, and ethnic diversity of the country as a whole. In addition, understanding recent changes in the overall size and composition of the federal workforce can indicate what changes may lie in the future.
Date: September 30, 2008
Creator: Copeland, Curtis W.
Object Type: Report
System: The UNT Digital Library
Advanced Energy Efficient Roof System (open access)

Advanced Energy Efficient Roof System

Energy consumption in buildings represents 40 percent of primary U.S. energy consumption, split almost equally between residential (22%) and commercial (18%) buildings.1 Space heating (31%) and cooling (12%) account for approximately 9 quadrillion Btu. Improvements in the building envelope can have a significant impact on reducing energy consumption. Thermal losses (or gains) from the roof make up 14 percent of the building component energy load. Infiltration through the building envelope, including the roof, accounts for an additional 28 percent of the heating loads and 16 percent of the cooling loads. These figures provide a strong incentive to develop and implement more energy efficient roof systems. The roof is perhaps the most challenging component of the building envelope to change for many reasons. The engineered roof truss, which has been around since 1956, is relatively low cost and is the industry standard. The roof has multiple functions. A typical wood frame home lasts a long time. Building codes vary across the country. Customer and trade acceptance of new building products and materials may impede market penetration. The energy savings of a new roof system must be balanced with other requirements such as first and life-cycle costs, durability, appearance, and ease of …
Date: September 30, 2008
Creator: Davidson, Jane
Object Type: Report
System: The UNT Digital Library