Military Housing: Opportunity for Reducing Planned Military Construction Costs for Barracks (open access)

Military Housing: Opportunity for Reducing Planned Military Construction Costs for Barracks

Correspondence issued by the General Accounting Office with an abstract that begins "We are reviewing the Department of Defense's (DOD) management of its unaccompanied enlisted permanent party housing, commonly referred to as barracks for unmarried servicemembers. We understand that over the next few years the services plan to eliminate barracks with gang latrines and provide private sleeping rooms (meet DOD's 1+1 barracks design standard) for all permanent party servicemembers. The Navy has an additional goal to provide barracks for sailors who currently live aboard ships when in homeport. To implement these goals, the services plan to spend about $6 billion over the next 7 years to construct new barracks. In addition to reviewing the services' plans and exploring opportunities for reducing costs, one of our objectives is to assess the consistency of and the rationale behind the services' barracks occupancy requirements. While we expect to complete our review of DOD's management of military barracks early in 2003, the purpose of this interim report is to bring to the attention Secretary of Defense the widely varying standards among the services regarding who should live in barracks, the effect this can have on program costs and quality of life, and the apparently …
Date: January 7, 2003
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Freight Transportation: National Policy and Strategies Can Help Improve Freight Mobility (open access)

Freight Transportation: National Policy and Strategies Can Help Improve Freight Mobility

A letter report issued by the Government Accountability Office with an abstract that begins "Continued development and efficient performance of the nation's freight transportation system is vital to maintaining a strong U.S. economy and sustaining our nation's competitive position in the global economy. Yet, increasing congestion on our nation's roads and rail lines threatens to undermine the efficiency of our freight transportation system. Although the Department of Transportation (DOT) has taken some steps to enhance freight mobility, there is growing concern that additional action is needed. To assist the Congress in enhancing national freight mobility, GAO reviewed (1) factors that contribute to constrained freight mobility and their effects in areas with nationally significant freight flows, and (2) approaches to address freight mobility in those areas and the challenges decision makers face in implementing those approaches. GAO analyzed freight transportation data and interviewed stakeholders in four areas with large freight flows."
Date: January 7, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
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
Single shot extreme ultraviolet laser imaging of nanostructures with wavelength resolution (open access)

Single shot extreme ultraviolet laser imaging of nanostructures with wavelength resolution

We have demonstrated near-wavelength resolution microscopy in the extreme ultraviolet. Images of 50 nm diameter nanotubes were obtained with a single {approx}1 ns duration pulse from a desk-top size 46.9 nm laser. We measured the modulation transfer function of the microscope for three different numerical aperture zone plate objectives, demonstrating that 54 nm half-period structures can be resolved. The combination of near-wavelength spatial resolution and high temporal resolution opens myriad opportunities in imaging, such as the ability to directly investigate dynamics of nanoscale structures.
Date: January 7, 2008
Creator: Jones, Juanita; Brewer, Courtney A.; Brizuela, Fernando; Wachulak, Przemyslaw; Martz, Dale H.; Chao, Weilun et al.
Object Type: Article
System: The UNT Digital Library
Microbiological, Geochemical and Hydrologic Processes Controlling Uranium Mobility: An Integrated Field-Scale Subsurface Research Challenge Site at Rifle, Colorado, Quality Assurance Project Plan (open access)

Microbiological, Geochemical and Hydrologic Processes Controlling Uranium Mobility: An Integrated Field-Scale Subsurface Research Challenge Site at Rifle, Colorado, Quality Assurance Project Plan

The U.S. Department of Energy (DOE) is cleaning up and/or monitoring large, dilute plumes contaminated by metals, such as uranium and chromium, whose mobility and solubility change with redox status. Field-scale experiments with acetate as the electron donor have stimulated metal-reducing bacteria to effectively remove uranium [U(VI)] from groundwater at the Uranium Mill Tailings Site in Rifle, Colorado. The Pacific Northwest National Laboratory and a multidisciplinary team of national laboratory and academic collaborators has embarked on a research proposed for the Rifle site, the object of which is to gain a comprehensive and mechanistic understanding of the microbial factors and associated geochemistry controlling uranium mobility so that DOE can confidently remediate uranium plumes as well as support stewardship of uranium-contaminated sites. This Quality Assurance Project Plan provides the quality assurance requirements and processes that will be followed by the Rifle Integrated Field-Scale Subsurface Research Challenge Project.
Date: January 7, 2008
Creator: Fix, N. J.
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
Reinforcement of Aluminum Castings with Dissimilar Metals (open access)

Reinforcement of Aluminum Castings with Dissimilar Metals

The project ''Reinforcement of Aluminum Casting with Dissimilar Metal'' was a Cooperative Research and Development Agreements (CRADAs) between Oak Ridge National Laboratory (ORNL) and Cummins Inc. This project, technologies have been developed to reinforce aluminum castings with steel insert. Defect-free bond between the steel insert and the aluminum casting has been consistently obtained. The push-out experiment indicated that the bond strength is higher than that of the Al-Fin method. Two patents have been granted to the project team that is comprised of Cummins Inc. and ORNL. This report contains four sections: the coating of the steel pins, the cast-in method, microstructure characterization, and the bond strength. The section of the coating of the steel pins contains coating material selection, electro-plating technique for plating Cu and Ni on steel, and diffusion bonding of the coatings to the steel. The section of cast-in method deals with factors that affecting the quality of the metallurgical bond between the coated steel and the aluminum castings. The results of microstructure characteristics of the bonding are presented in the microstructure characterization section. A push-out experiment and the results obtained using this method is described in the section of bond strength/mechanical property.
Date: January 7, 2004
Creator: Han, Q
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
Progress in Large Period Multilayer Coatings for High Harmonic and Solar Applications (open access)

Progress in Large Period Multilayer Coatings for High Harmonic and Solar Applications

Multilayer coatings for normal incidence optics designed for the long wavelength region (25 nm < {lambda} < 50 nm) are particularly challenging due to the few number of layers that can be utilized in the reflection. Recently, Mg/SiC multilayers have been fabricated with normal incidence reflectivity in the vicinity of 40% for wavelengths near the He-II line at 30.4 nm. Motivated by this success we have investigated the use of a tri-band multilayer to increase the bandwidth while maintaining the reflectivity. The multilayers were deposited by conventional magnetron sputtering. Using Mg/SiC bilayers a reflectivity of 45% was achieved at 27 to 32 nm at an angle of 5 deg from normal. The Mg/Sc/SiC multilayer systems have also been investigated. It obtained a near normal incidence reflectivity of 35% while increasing the bandwidth by a factor of 2. These results are very encouraging for the possibility of more widespread applications of normal incidence optics in high harmonic applications.
Date: January 7, 2008
Creator: Jones, Juanita; Aquila, Andrew; Salmassi, Farhad & Gullikson, Eric
Object Type: Article
System: The UNT Digital Library
Decoding sequential vs non-sequential two-photon double ionizationof helium using nuclear recoil (open access)

Decoding sequential vs non-sequential two-photon double ionizationof helium using nuclear recoil

Above 54.4 eV, two-photon double ionization of helium isdominated by a sequential absorption process, producing characteristicbehavior in the single and triple differential cross sections. We showthat the signature of this process is visible in the nuclear recoil crosssection, integrated over all energy sharings of the ejected electrons,even below the threshold for the sequential process. Since nuclear recoilmomentum imaging does not require coincident photoelectron measurement,the predicted images present a viable target for future experiments withnew short-pulse VUV and soft X-ray sources.
Date: January 7, 2008
Creator: Horner, Daniel A.; Rescigno, Thomas N. & McCurdy, C. William
Object Type: Article
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
Simple de Sitter Solutions (open access)

Simple de Sitter Solutions

We present a framework for de Sitter model building in type IIA string theory, illustrated with specific examples. We find metastable dS minima of the potential for moduli obtained from a compactification on a product of two Nil three-manifolds (which have negative scalar curvature) combined with orientifolds, branes, fractional Chern-Simons forms, and fluxes. As a discrete quantum number is taken large, the curvature, field strengths, inverse volume, and four dimensional string coupling become parametrically small, and the de Sitter Hubble scale can be tuned parametrically smaller than the scales of the moduli, KK, and winding mode masses. A subtle point in the construction is that although the curvature remains consistently weak, the circle fibers of the nilmanifolds become very small in this limit (though this is avoided in illustrative solutions at modest values of the parameters). In the simplest version of the construction, the heaviest moduli masses are parametrically of the same order as the lightest KK and winding masses. However, we provide a method for separating these marginally overlapping scales, and more generally the underlying supersymmetry of the model protects against large corrections to the low-energy moduli potential.
Date: January 7, 2008
Creator: Silverstein, Eva
Object Type: Report
System: The UNT Digital Library
Averaging of Stochastic Equations for Flow and Transport in PorousMedia (open access)

Averaging of Stochastic Equations for Flow and Transport in PorousMedia

It is well known that at present exact averaging of theequations of flow and transport in random porous media have been realizedfor only a small number of special fields. Moreover, the approximateaveraging methods are not yet fully understood. For example, theconvergence behavior and the accuracy of truncated perturbation seriesare not well known; and in addition, the calculation of the high-orderperturbations is very complicated. These problems for a long time havestimulated attempts to find the answer for the question: Are there inexistence some exact general and sufficiently universal forms of averagedequations? If the answer is positive, there arises the problem of theconstruction of these equations and analyzing them. There are manypublications on different applications of this problem to various fields,including: Hydrodynamics, flow and transport in porous media, theory ofelasticity, acoustic and electromagnetic waves in random fields, etc.Here, we present a method of finding some general form of exactlyaveraged equations for flow and transport in random fields by using (1)some general properties of the Green s functions for appropriatestochastic problems, and (2) some basic information about the randomfields of the conductivity, porosity and flow velocity. We presentgeneral forms of exactly averaged non-local equations for the followingcases: (1) steady-state flow with sources in …
Date: January 7, 2005
Creator: Shvidler, Mark & Karasaki, Kenzi
Object Type: Article
System: The UNT Digital Library
D and Ds Hadronic Branching Fractions at B Factories (open access)

D and Ds Hadronic Branching Fractions at B Factories

Recent measurements of hadronic branching fractions of D and D{sub s} mesons, performed by the BABAR and Belle experiments at the asymmetric e{sup +}e{sup -} B factories colliders PEP II and KEKB, are reviewed.
Date: January 7, 2008
Creator: Pappagallo, Marco
Object Type: Article
System: The UNT Digital Library
A Korarchael Genome Reveals Insights into the Evolution of the Archaea (open access)

A Korarchael Genome Reveals Insights into the Evolution of the Archaea

The candidate division Korarchaeota comprises a group of uncultivated microorganisms that, by their small subunit rRNA phylogeny, may have diverged early from the major archaeal phyla Crenarchaeota and Euryarchaeota. Here, we report the initial characterization of a member of the Korarchaeota with the proposed name, ?Candidatus Korarchaeum cryptofilum,? which exhibits an ultrathin filamentous morphology. To investigate possible ancestral relationships between deep-branching Korarchaeota and other phyla, we used whole-genome shotgun sequencing to construct a complete composite korarchaeal genome from enriched cells. The genome was assembled into a single contig 1.59 Mb in length with a G + C content of 49percent. Of the 1,617 predicted protein-coding genes, 1,382 (85percent) could be assigned to a revised set of archaeal Clusters of Orthologous Groups (COGs). The predicted gene functions suggest that the organism relies on a simple mode of peptide fermentation for carbon and energy and lacks the ability to synthesize de novo purines, CoA, and several other cofactors. Phylogenetic analyses based on conserved single genes and concatenated protein sequences positioned the korarchaeote as a deep archaeal lineage with an apparent affinity to the Crenarchaeota. However, the predicted gene content revealed that several conserved cellular systems, such as cell division, DNA replication, and …
Date: January 7, 2008
Creator: Lapidus, Alla; Elkins, James G.; Podar, Mircea; Graham, David E.; Makarova, Kira S.; Wolf, Yuri et al.
Object Type: Article
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
LESSONS LEARNED IN OPERATING THE HOSE-IN-HOSE SYSTEM FOR TRANSFSERRING SLUDGE AT HANFORDS K-BASINS (open access)

LESSONS LEARNED IN OPERATING THE HOSE-IN-HOSE SYSTEM FOR TRANSFSERRING SLUDGE AT HANFORDS K-BASINS

In May 2007, the Department of Energy and the Fluor Hanford K Basin Closure Project completed transferring sludge from the K East Basin to new containers in the K West Basin using a Hose-in-Hose system. This project presented a number of complex and unique technical, operational, and management challenges that had to be resolved to complete the required transfers and satisfy project milestones. The project team (including DOE; regulators; and Fluor management, operations, maintenance, engineering and all other support organizations) found innovative solutions to each challenge. This paper records lessons learned during the operational phase of the sludge transfer via the Hose-In-Hose system. The subject is limited to the operational phase and does not cover design, development, testing or turnover. A discussion of the situation or problem encountered is provided, along with the lesson learned as applicable to a future program or project.
Date: January 7, 2008
Creator: MW, PERES
Object Type: Article
System: The UNT Digital Library
Geochemical Characterization Data Package for the Vadose Zone in the Single-Shell Tank Waste Management Areas at the Hanford Site (open access)

Geochemical Characterization Data Package for the Vadose Zone in the Single-Shell Tank Waste Management Areas at the Hanford Site

This data package discusses the geochemistry of vadose zone sediments beneath the single-shell tank (SST) farms at the U.S. Department of Energy’s (DOE’s) Hanford Site. The purpose of the report is to provide a review of the most recent and relevant geochemical information available for the vadose zone beneath the SST farms and the Integrated Disposal Facility (IDF).
Date: January 7, 2008
Creator: Cantrell, Kirk J.; Brown, Christopher F.; Serne, R. Jeffrey & Krupka, Kenneth M.
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