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Crosscutting Technology Development at the Center for Advanced Separation Technologies
The U.S. is the largest producer of mining products in the world. In 2003, U.S. mining operations produced $57 billion worth of raw materials that contributed a total of $564 billion to the nation's wealth. Despite these contributions, the mining industry has not been well supported with research and development funds as compared to mining industries in other countries. To overcome this problem, the Center for Advanced Separation Technologies (CAST) was established to develop technologies that can be used by the U.S. mining industry to create new products, reduce production costs, and meet environmental regulations. Originally set up by Virginia Tech and West Virginia University, this endeavor has been expanded into a seven-university consortium -- Virginia Tech, West Virginia University, University of Kentucky, University of Utah, Montana Tech, New Mexico Tech and University of Nevada, Reno - that is supported through U.S. DOE Cooperative Agreement No. DE-FC26-02NT41607: Crosscutting Technology Development at the Center for Advanced Separation Technologies. Much of the research to be conducted with Cooperative Agreement funds will be longer-term, high-risk, basic research and will be carried out in five broad areas: (1) Solid-solid separation; (2) Solid-liquid separation; (3) Chemical/biological extraction; (4) Modeling and control; and (5) Environmental control. …
Date:
October 31, 2009
Creator:
Hull, Christopher
Object Type:
Report
System:
The UNT Digital Library
Impacts of Biofilm Formation on Cellulose Fermentation
This project addressed four major areas of investigation: i) characterization of formation of Cellulomonas uda biofilms on cellulose; ii) characterization of Clostridium phytofermentans biofilm development; colonization of cellulose and its regulation; iii) characterization of Thermobifida fusca biofilm development; colonization of cellulose and its regulation; and iii) description of the architecture of mature C. uda, C. phytofermentans, and T. fusca biofilms. This research is aimed at advancing understanding of biofilm formation and other complex processes involved in the degradation of the abundant cellulosic biomass, and the biology of the microbes involved. Information obtained from these studies is invaluable in the development of practical applications, such as the single-step bioconversion of cellulose-containing residues to fuels and other bioproducts. Our results have clearly shown that cellulose-decomposing microbes rapidly colonize cellulose and form complex structures typical of biofilms. Furthermore, our observations suggest that, as cells multiply on nutritive surfaces during biofilms formation, dramatic cell morphological changes occur. We speculated that morphological changes, which involve a transition from rod-shaped cells to more rounded forms, might be more apparent in a filamentous microbe. In order to test this hypothesis, we included in our research a study of biofilm formation by T. fusca, a thermophilic cellulolytic actinomycete …
Date:
October 31, 2009
Creator:
Leschine, Susan
Object Type:
Report
System:
The UNT Digital Library
Microbial Fermentation of Abundant Biopolymers: Cellulose and Chitin
Our research has dealt with seven major areas of investigation: i) characterization of cellulolytic members of microbial consortia, with special attention recently given to Clostridium phytofermentans, a bacterium that decomposes cellulose and produces uncommonly large amounts of ethanol, ii) investigations of the chitinase system of Cellulomonas uda; including the purification and characterization of ChiA, the major component of this enzyme system, iii) molecular cloning, sequence and structural analysis of the gene that encodes ChiA in C. uda, iv) biofilm formation by C. uda on nutritive surfaces, v) investigations of the effects of humic substances on cellulose degradation by anaerobic cellulolytic microbes, vi) studies of nitrogen metabolism in cellulolytic anaerobes, and vii) understanding the molecular architecture of the multicomplex cellulase-xylanase system of Clostridium papyrosolvens. Also, progress toward completing the research of more recent projects is briefly summarized. Major accomplishments include: 1. Characterization of Clostridium phytofermentans, a cellulose-fermenting, ethanol-producing bacterium from forest soil. The characterization of a new cellulolytic species isolated from a cellulose-decomposing microbial consortium from forest soil was completed. This bacterium is remarkable for the high concentrations of ethanol produced during cellulose fermentation, typically more than twice the concentration produced by other species of cellulolytic clostridia. 2. Examination of the …
Date:
October 31, 2009
Creator:
Leschine, Susan
Object Type:
Report
System:
The UNT Digital Library
Phase I (CATTS Theory), Phase II (Milne Point), Phase III (Hydrate Ridge)
This study introduces a new type of âcumulative seismic attributeâ (CATT) which quantifies gas hydrates resources in Hydrate Ridge offshore Oregon. CATT is base on case-specific transforms that portray hydrated reservoir properties. In this study we used a theoretical rock physics model to correct measured velocity log data.
Date:
October 31, 2009
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Production of Seamless Superconducting Radio Frequency Cavities from Ultra-fine Grained Niobium, Phase II Final Report
The positron and electron linacs of the International Linear Collider (ILC) will require over 14,000, nine-cell, one meter length, superconducting radio frequency (SRF) cavities [ILC Reference Design Report, 2007]. Manufacturing on this scale will benefit from more efficient fabrication methods. The current methods of fabricating SRF cavities involve deep drawing of the halves of each of the elliptical cells and joining them by high-vacuum, electron beam welding, with at least 19 circumferential welds per cavity. The welding is costly and has undesirable effects on the cavity surfaces, including grain-scale surface roughening at the weld seams. Hydroforming of seamless tubes avoids welding, but hydroforming of coarse-grained seamless tubes results in strain-induced surface roughening. Surface roughness limits accelerating fields, because asperities prematurely exceed the critical magnetic field and become normal conducting. This project explored the technical and economic feasibility of an improved processing method for seamless tubes for hydroforming. Severe deformation of bulk material was first used to produce a fine structure, followed by extrusion and flow-forming methods of tube making. Extrusion of the randomly oriented, fine-grained bulk material proceeded under largely steady-state conditions, and resulted in a uniform structure, which was found to be finer and more crystallographically random than standard …
Date:
October 31, 2009
Creator:
Roy Crooks, Ph.D., P.E.
Object Type:
Report
System:
The UNT Digital Library
SPARTICUS: Small Particles in Cirrus Science and Operations Plan
From a mass-weighted perspective, cirrus clouds exert an enormous influence on the radiative energy budget of the earth’s climate system. Owing to their location in the cold upper troposphere, cirrus can significantly reduce the outgoing longwave radiation while, at the same time, remaining relatively transmissive to solar energy. Thus, cirrus clouds are the only cloud genre that can exert a direct radiative warming influence on the climate system (Ackerman et al. 1988). It is not surprising, therefore, that general circulation models (GCMs) are especially sensitive to the presence of cirrus in the model atmosphere. Lohmann and Roeckner (1995), for instance, show that the climate sensitivity can vary by as much as 40% due to the properties of cirrus varying between transparent and opaque limits. Lohmann and Roeckner (1995) also identify a key feedback by cirrus that is often overlooked; on longer time scales cloud heating in the upper troposphere can act to maintain and modulate the general circulation of the atmosphere through accelerating the subtropical and polar jet streams. Understanding these mechanisms and representing them in models is complicated by the fact that cirrus properties vary over an enormous dynamic range compared to most other clouds.
Date:
October 31, 2009
Creator:
J Mace, E Jensen, G McFarquhar, J Comstock, T Ackerman, D Mitchell, X Liu, T Garrett
Object Type:
Report
System:
The UNT Digital Library
Analysis of Voltage Signals from Superconducting Accelerator Magnets
We present two techniques used in the analysis of voltage tap data collected during recent tests of superconducting magnets developed by the Superconducting Magnet Program at Lawrence Berkeley National Laboratory. The first technique was used on a quadrupole to provide information about quench origins that could not be obtained using the time-of-flight method. The second technique illustrates the use of data from transient flux imbalances occurring during magnet ramping to diagnose changes in the current-temperature margin of a superconducting cable. In both cases, the results of this analysis contributed to make improvements on subsequent magnets.
Date:
October 30, 2009
Creator:
Lizarazo, J.; Caspi, S.; Ferracin, P.; Joseph, J.; Lietzke, A. F.; Sabbi, G. L. et al.
Object Type:
Article
System:
The UNT Digital Library
ATF2 Commissioning
ATF2 is a final-focus test beam line that aims to focus the low-emittance beam from the ATF damping ring to a beam size of about 37 nm, and at the same time to demonstrate nm beam stability, using numerous advanced beam diagnostics and feedback tools. The construction has been finished at the end of 2008 and the beam commissioning of ATF2 has started in December of 2008. ATF2 is constructed and commissioned by ATF international collaborations with strong US, Asian and European participation.
Date:
October 30, 2009
Creator:
Seryi, A.; Christian, G.; Parker, B.; Schulte, D.; Delahaye, J. -P.; Tomas, R. et al.
Object Type:
Article
System:
The UNT Digital Library
Aviation Safety: Information on the Safety Effects of Modifying the Age Standard for Commercial Pilots
Correspondence issued by the Government Accountability Office with an abstract that begins "The Fair Treatment for Experienced Pilots Act (the act) extended the federal age standard for pilots of large commercial aircraft from 60 to 65 years of age. The act also requires us to report--no later than 24 months after its enactment--on the effect, if any, of this change on aviation safety. This report responds to that requirement."
Date:
October 30, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Text
System:
The UNT Digital Library
Black Lung Benefits Program: Administrative and Structural Changes Could Improve Miners' Ability to Pursue Claims
A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Labor (DOL) Black Lung Benefits Program provides medical and income assistance to coal miners who suffer total disability or death due to lung disease caused by coal dust. To provide insight into DOL's administration of the Black Lung Benefits Program, GAO is reporting on (1) how long it takes to process and resolve black lung benefits claims; (2) at what rate and for what reasons black lung claims and appeals are denied by DOL; and (3) what barriers, if any, confront miners or their survivors in pursuing their claims. GAO collected and analyzed black lung claims and appeals data and interviewed officials at relevant federal agencies, national organizations, and selected local organizations at two sites."
Date:
October 30, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library
Branching fractions and charge asymmetries in charmless hadronic decays at BABAR
We present measurements of branching fraction, polarization and charge asymmetry in charmless hadronic B decays with {eta}, {eta}{prime}, {omega}, and b{sub 1} in the final state. All the results use the final BABAR dataset.
Date:
October 30, 2009
Creator:
Biassoni, Pietro
Object Type:
Article
System:
The UNT Digital Library
Coal Combustion Residue: Status of EPA's Efforts to Regulate Disposal
Correspondence issued by the Government Accountability Office with an abstract that begins "On December 22, 2008, a breach in a surface impoundment (or storage pond) dike at the Tennessee Valley Authority (TVA) Kingston Fossil Plant in Tennessee resulted in the release of 5.4 million cubic yards of coal ash--also referred to as coal combustion residue (CCR)--into the nearby Emory River. The spill covered more than 300 acres and made 3 homes uninhabitable; it damaged 23 other homes, plus roads, rail lines, and utilities. TVA estimated the cleanup will cost between $933 million and $1.2 billion and take 2 to 3 years to complete. In light of the spill in Kingston, Congress asked us to identify: (1) the number of surface impoundments for storing CCR in the United States and their location; (2) problems, if any, with the storage of coal ash, and how those problems are being addressed; and (3) the type of federal oversight that exists for CCR and what, if any, issues need to be resolved. We briefed your staffs on October 1, 2009, and September 28, 2009, respectively, on the results of this work. This report summarizes and transmits that briefing. The full briefing is reprinted in …
Date:
October 30, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Text
System:
The UNT Digital Library
A Concept of Plasma Wake Field Acceleration Linear Collider (PWFA-LC)
Plasma Wake-Field Acceleration (PWFA) has demonstrated acceleration gradients above 50 GeV/m. Simulations have shown drive/witness bunch configurations that yield small energy spreads in the accelerated witness bunch and high energy transfer efficiency from the drive bunch to the witness bunch, ranging from 30% for a Gaussian drive bunch to 95% for a shaped longitudinal profile. These results open the opportunity for a linear collider that could be compact, efficient and more cost effective that the present microwave technologies. A concept of a PWFA-based Linear Collider (PWFA-LC) has been developed and is described in this paper. The drive beam generation and distribution, requirements on the plasma cells, and optimization of the interaction region parameters are described in detail. The R&D steps needed for further development of the concept are also outlined.
Date:
October 30, 2009
Creator:
Seryi, Andrei; Hogan, Mark; Pei, Shilun; Raubenheimer, Tor; Tenenbaum, Peter; Katsouleas, Tom et al.
Object Type:
Article
System:
The UNT Digital Library
Connecting Reionization to the Local Universe
We present results of combined N-body and three-dimensional reionization calculations to determine the relationship between reionization history and local environment in a volume 1 Gcp h$sup -1$ across and a resolution of about 1 Mpc. We achieve this by applying three dimensional simulations of reionization, based on the extended Press-Schechter formalism, to the same initial conditions as the N-body simulations. We resolve about 2 X 10$sup 6$ halos of mass greater than ~ 10$sup 12$M at z = 0, and determine the relationship between halo mass and reionization epoch for galaxies and clusters. For our fiducial reionization model, in which reionization begins at z ~ 15 and ends by z ~ 6, we find a strong bias for cluster-size halos to be in the regions which reionized first, at redshifts 10 < z < 15. Consequently, material in clusters was reionized within relatively small regious, on the order of a few Mpc, implying that all clusters in our calculation were reionized by their own progenitors. Milky Way mass halos were on average reionized later and by larger regions, with a distribution most similar to the global one, indicating that low mass halos are nearly uncorrelated with reionization when only halo …
Date:
October 30, 2009
Creator:
Alvarez, Marcelo
Object Type:
Article
System:
The UNT Digital Library
Constraining Emission Models of Luminous Blazar Sources
Many luminous blazars which are associated with quasar-type active galactic nuclei display broad-band spectra characterized by a large luminosity ratio of their high-energy ({gamma}-ray) and low-energy (synchrotron) spectral components. This large ratio, reaching values up to 100, challenges the standard synchrotron self-Compton models by means of substantial departures from the minimum power condition. Luminous blazars have also typically very hard X-ray spectra, and those in turn seem to challenge hadronic scenarios for the high energy blazar emission. As shown in this paper, no such problems are faced by the models which involve Comptonization of radiation provided by a broad-line-region, or dusty molecular torus. The lack or weakness of bulk Compton and Klein-Nishina features indicated by the presently available data favors production of {gamma}-rays via up-scattering of infrared photons from hot dust. This implies that the blazar emission zone is located at parsec-scale distances from the nucleus, and as such is possibly associated with the extended, quasi-stationary reconfinement shocks formed in relativistic outflows. This scenario predicts characteristic timescales for flux changes in luminous blazars to be days/weeks, consistent with the variability patterns observed in such systems at infrared, optical and {gamma}-ray frequencies. We also propose that the parsec-scale blazar activity can …
Date:
October 30, 2009
Creator:
Sikora, Marek; Stawarz, Lukasz; Moderski, Rafal; Nalewajko, Krzysztof & Madejski, Greg
Object Type:
Article
System:
The UNT Digital Library
Construction and Performance of the BaBar DIRC
The new type of ring-imaging Cherenkov detector technology called DIRC (an acronym for Detection of Internally Reflected Cherenkov (Light)) has been used successfully for hadronic particle identification in the BABAR experiment at the B Factory (PEP-II) located at the SLAC National Accelerator Laboratory. This paper describes the R&D for and the construction of the DIRC radiator bars and the performance of the DIRC during more than eight years of B Factory operation.
Date:
October 30, 2009
Creator:
Schwiening, Jochen
Object Type:
Article
System:
The UNT Digital Library
The Controlled Synthesis of Metastable Oxides Utilizing Epitaxy and Epitaxial Stabilization
The research enabled by this DOE grant led to 13 publications in leading refereed journals including Physical Review Letters and Applied Physics Letters as well as feature articles in the Journal of the American Ceramic Society and Physik Journal (the German equivalent of Physics Today distributed to all members of the German Physical Society) on the controlled synthesis of metastable oxides utilizing epitaxy and epitaxial stabilization. In total our results fill over 100 pages of archived journals and are attached.
Date:
October 30, 2009
Creator:
Schlom, Dr. Darrell G.
Object Type:
Report
System:
The UNT Digital Library
Coupling Sorption to Soil Weathering During Reactive Transport: Impacts of Mineral Transformation and Sorbent Aging on Contaminant Speciation and Mobility
This project aimed for a predictive-mechanistic understanding of the coupling between mineral weathering and contaminant (Cs, Sr, I) transport/fate in caustic waste-impacted sediments. Based on our prior studies of model clay mineral systems, we postulated that contaminant uptake to Hanford sediments would reflect concurrent adsorption and co-precipitation effects. Our specific objectives were: (1) to assess the molecular-scale mechanisms responsible for time-dependent sequestration of contaminants (Cs, Sr and I) during penetration of waste-induced weathering fronts; (2) to determine the rate and extent of contaminant release from the sorbed state; (3) to develop a reactive transport model based on molecular mechanisms and macroscopic flow experiments [(1) and (2)] that simulates adsorption, aging, and desorption dynamics. Progress toward achieving each of these objectives is discussed below. We observed unique molecular mechanisms for sequestration of Sr, Cs and I during native silicate weathering in caustic waste. Product solids, which included poorly crystalline aluminosilicates and well-crystallized zeolites and feldspathoids, accumulate contaminant species during crystal growth.
Date:
October 30, 2009
Creator:
Chorover, J.; Mueller, K. T.; O'Day, P. A.; Serne, R. J. & Steefel, C. I.
Object Type:
Report
System:
The UNT Digital Library
Facility for Advanced Accelerator Experimental Tests at SLAC (FACET) Conceptual Design Report
This Conceptual Design Report (CDR) describes the design of FACET. It will be updated to stay current with the developing design of the facility. This CDR begins as the baseline conceptual design and will evolve into an 'as-built' manual for the completed facility. The Executive Summary, Chapter 1, gives an introduction to the FACET project and describes the salient features of its design. Chapter 2 gives an overview of FACET. It describes the general parameters of the machine and the basic approaches to implementation. The FACET project does not include the implementation of specific scientific experiments either for plasma wake-field acceleration for other applications. Nonetheless, enough work has been done to define potential experiments to assure that the facility can meet the requirements of the experimental community. Chapter 3, Scientific Case, describes the planned plasma wakefield and other experiments. Chapter 4, Technical Description of FACET, describes the parameters and design of all technical systems of FACET. FACET uses the first two thirds of the existing SLAC linac to accelerate the beam to about 20GeV, and compress it with the aid of two chicanes, located in Sector 10 and Sector 20. The Sector 20 area will include a focusing system, the …
Date:
October 30, 2009
Creator:
Amann, J. & Bane, K.
Object Type:
Report
System:
The UNT Digital Library
Federal Energy Management: Agencies Are Taking Steps to Meet High-Performance Federal Building Requirements, but Face Challenges
A letter report issued by the Government Accountability Office with an abstract that begins "The federal government is the nation's largest energy consumer. The Energy Independence and Security Act of 2007 (EISA) establishes high-performance federal building requirements that include reducing energy use and managing storm water runoff. The Department of Energy (DOE), General Services Administration (GSA), Office of Management and Budget (OMB), and Environmental Protection Agency (EPA) are implementing and, in turn, helping other agencies to implement EISA requirements. The American Recovery and Reinvestment Act of 2009 (Recovery Act) provides funding that some agencies can use to carry out EISA high-performance federal building requirements. This report, required by EISA, addresses (1) what implementing agencies are doing to direct and assist other agencies in meeting key EISA high-performance federal building requirements, (2) how implementing agencies are planning to use Recovery Act funds to meet key requirements, and (3) what challenges implementing and other agencies might face. To do this, GAO reviewed legal materials, guidance, draft energy data, and other documents and interviewed agency officials and stakeholders. DOE and GSA generally agreed with the report's findings and conclusions and provided written comments. OMB neither agreed nor disagreed with the report and provided …
Date:
October 30, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library
Final Report: Migration Mechanisms for Large-scale Parallel Applications
Process migration is the ability to transfer a process from one machine to another. It is a useful facility in distributed computing environments, especially as computing devices become more pervasive and Internet access becomes more ubiquitous. The potential benefits of process migration, among others, are fault resilience by migrating processes off of faulty hosts, data access locality by migrating processes closer to the data, better system response time by migrating processes closer to users, dynamic load balancing by migrating processes to less loaded hosts, and improved service availability and administration by migrating processes before host maintenance so that applications can continue to run with minimal downtime. Although process migration provides substantial potential benefits and many approaches have been considered, achieving transparent process migration functionality has been difficult in practice. To address this problem, our work has designed, implemented, and evaluated new and powerful transparent process checkpoint-restart and migration mechanisms for desktop, server, and parallel applications that operate across heterogeneous cluster and mobile computing environments. A key aspect of this work has been to introduce lightweight operating system virtualization to provide processes with private, virtual namespaces that decouple and isolate processes from dependencies on the host operating system instance. This decoupling …
Date:
October 30, 2009
Creator:
Nieh, Jason
Object Type:
Report
System:
The UNT Digital Library
Fire Grants: FEMA Has Met Most Requirements for Awarding Fire Grants, but Additional Actions Would Improve Its Grant Process
A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Homeland Security, through the Federal Emergency Management Agency (FEMA), awards grants to fire departments and other organizations for equipment, staffing, and other needs. As of July 2009, FEMA had received about 25,000 and 22,000 applications for its fiscal years 2007 and 2008 fire grant programs, respectively, and had awarded more than 5,000 grants in both years. GAO was congressionally directed to review the application and award process for these grants. This report addresses the (1) extent to which FEMA has met statutory and program requirements for distributing the grant funds; (2) actions FEMA has taken to provide assistance to grant applicants and involve the fire service community in the grant process; and (3) extent to which FEMA has ensured that its grant process is accessible, clear, and consistent with requirements, including its grant guidance. GAO analyzed relevant laws and interviewed 36 randomly selected grant applicants to obtain their views, but the results are not generalizable."
Date:
October 30, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library
Free Electron Laser for Gamma-Gamma Collider at a Low-Energy Option of International Linear Collider
Different scenarios of a start-up with International Linear Collider (ILC) are under discussion at the moment in the framework of the Global Design Effort (GDE). One of them assumes construction of the ILC in stages from some minimum CM energy up to final target of 500 GeV CM energy. Gamma-gamma collider with CM energy of 180GeV is considered as a candidate for the first stage of the facility. In this report we present conceptual design of a free electron laser as a source of primary photons for the first stage of ILC.
Date:
October 30, 2009
Creator:
Saldin, Evgeny; Schneidmiller, Evgeny; Yurkov, Mikhail & Seryi, Andrei
Object Type:
Article
System:
The UNT Digital Library
Household Goods Moving Industry: Progress Has Been Made in Enforcement, but Increased Focus on Consumer Protection Is Needed
A letter report issued by the Government Accountability Office with an abstract that begins "Each year, the Federal Motor Carrier Safety Administration (FMCSA) within the Department of Transportation (DOT) receives about 3,000 consumer complaints regarding interstate moving companies: some involve egregious offenses, such as holding goods hostage. Over the years, Congress and GAO have raised concerns about the adequacy of FMCSA's oversight of the industry. As requested, GAO reviewed the (1) extent to which states have used authority in the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) to take federal enforcement action against interstate movers and challenges in using that authority; (2) extent and timeliness of FMCSA's progress in its consumer protection efforts; and (3) advantages and disadvantages of options for enhancing consumer protection in the industry. GAO analyzed applicable laws and regulations; interviewed government, moving industry, and consumer protection officials; surveyed state regulatory agencies and state attorneys general; and analyzed consumer protection models."
Date:
October 30, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library