Search Results

open access

Carbonic Acid Pretreatment of Biomass

Description: This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. 1) Solidify the theoretical understanding of the binary CO2/H2O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. 2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. 3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. 4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. 5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for the use of carbonic acid compared to …
Date: May 31, 2003
Creator: Walsum, G. Peter van; Jayawardhana, Kemantha; Yourchisin, Damon; McWilliams, Robert & Castleberry, Vanessa
Partner: UNT Libraries Government Documents Department
open access

Development of Alternative Fuels and Chemicals From Synthesis Gas

Description: This Final Report for Cooperative Agreement No. DE-FC22-95PC93052, the ''Development of Alternative Fuels and Chemicals from Synthesis Gas,'' was prepared by Air Products and Chemicals, Inc. (Air Products), and covers activities from 29 December 1994 through 31 July 2002. The overall objectives of this program were to investigate potential technologies for the conversion of synthesis gas (syngas), a mixture primarily of hydrogen (H{sub 2}) and carbon monoxide (CO), to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at the LaPorte, Texas Alternative Fuels Development Unit (AFDU). Laboratory work was performed by Air Products and a variety of subcontractors, and focused on the study of the kinetics of production of methanol and dimethyl ether (DME) from syngas, the production of DME using the Liquid Phase Dimethyl Ether (LPDME{trademark}) Process, the conversion of DME to fuels and chemicals, and the production of other higher value products from syngas. Four operating campaigns were performed at the AFDU during the performance period. Tests of the Liquid Phase Methanol (LPMEOH{trademark}) Process and the LPDME{trademark} Process were made to confirm results from the laboratory program and to allow for the study of the hydrodynamics of the slurry bubble column reactor (SBCR) at a significant engineering scale. Two campaigns demonstrated the conversion of syngas to hydrocarbon products via the slurry-phase Fischer-Tropsch (F-T) process. Other topics that were studied within this program include the economics of production of methyl tert-butyl ether (MTBE), the identification of trace components in coal-derived syngas and the means to economically remove these species, and the study of systems for separation of wax from catalyst in the F-T process. The work performed under this Cooperative Agreement has continued to promote the development of technologies that use clean syngas produced from any one of a variety of sources (including …
Date: May 31, 2003
Creator: Tijrn, Peter J.
Partner: UNT Libraries Government Documents Department
open access

Final Report, Distillation Column Flooding Predictor

Description: The Flooding Predictor is an advanced process control strategy comprising a patented pattern-recognition methodology that identifies pre-flood patterns discovered to precede flooding events in distillation columns. The grantee holds a U.S. patent on the modeling system. The technology was validated at the Separations Research Program, The University of Texas at Austin under a grant from the U. S. Department of Energy, Inventions & Innovation Program. Distillation tower flooding occurs at abnormally high vapor and/or liquid rates. The loss in tray efficiencies is attributed to unusual behavior of liquid inventories inside the column leading to conditions of flooding of the space in between trays with liquid. Depending on the severity of the flood condition, consequences range from off spec products to equipment damage and tower shutdown. This non-intrusive pattern recognition methodology, processes signal data obtained from existing column instrumentation. Once the pattern is identified empirically, it is modeled and coded into the plant's distributed control system. The control system is programmed to briefly "unload" the tower each time the pattern appears. The unloading takes the form of a momentary reduction in column severity, e.g., decrease bottom temperature, reflux or tower throughput. Unloading the tower briefly at the pre-flood state causes long-term column operation to become significantly more stable - allowing an increase in throughput and/or product purity. The technology provides a wide range of value between optimization and flooding. When a distillation column is not running at capacity, it should be run in such a way ("pushed") that optimal product purity is achieved. Additional benefits include low implementation and maintenance costs, and a high level of console operator acceptance. The previous commercial applications experienced 98% uptime over a four-year period. Further, the technology is unique in its ability to distinguish between different flooding mechanisms within the same tower, e.g., liquid and …
Date: May 31, 2003
Creator: Dzyacky, George E.
Partner: UNT Libraries Government Documents Department
open access

Geologic Controls of Hydrocarbon Occurrence in the Southern Appalachian Basin in Eastern Tennessee, Southwestern Virginia, Eastern Kentucky, and Southern West Virginia

Description: This report summarizes the first-year accomplishments of a three-year program to investigate the geologic controls of hydrocarbon occurrence in the southern Appalachian basin in eastern Tennessee, southwestern Virginia, eastern Kentucky, and southern West Virginia. The project: (1) employs the petroleum system approach to understand the geologic controls of hydrocarbons; (2) attempts to characterize the T-P parameters driving petroleum evolution; (3) attempts to obtain more quantitative definitions of reservoir architecture and identify new traps; (4) is working with USGS and industry partners to develop new play concepts and geophysical log standards for subsurface correlation; and (5) is geochemically characterizing the hydrocarbons (cooperatively with USGS). First-year results include: (1) meeting specific milestones (determination of thrust movement vectors, fracture analysis, and communicating results at professional meetings and through publication). All milestones were met. Movement vectors for Valley and Ridge thrusts were confirmed to be west-directed and derived from pushing by the Blue Ridge thrust sheet, and fan about the Tennessee salient. Fracture systems developed during Paleozoic, Mesozoic, and Cenozoic to Holocene compressional and extensional tectonic events, and are more intense near faults. Presentations of first-year results were made at the Tennessee Oil and Gas Association meeting (invited) in June, 2003, at a workshop in August 2003 on geophysical logs in Ordovician rocks, and at the Eastern Section AAPG meeting in September 2003. Papers on thrust tectonics and a major prospect discovered during the first year are in press in an AAPG Memoir and published in the July 28, 2003, issue of the Oil and Gas Journal. (2) collaboration with industry and USGS partners. Several Middle Ordovician black shale samples were sent to USGS for organic carbon analysis. Mississippian and Middle Ordovician rock samples were collected by John Repetski (USGS) and RDH for conodont alteration index determination to better define regional P-T conditions. Efforts …
Date: May 31, 2003
Creator: Hatcher, Robert D.
Partner: UNT Libraries Government Documents Department
open access

Southern Fine Particulate Monitoring Project

Description: This final project report presents experimental details, results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the October, 2001-September, 2002 study period.The host site for these measurement activities is the North Birmingham PM monitoring station by the Jefferson County Health Department in Birmingham, AL.The continuous data include PM{sub 2.5} mass concentrations measured by TEOM, particle sulfate using the R&P 8400S monitor, particle size distributions measured by SMPS and APS monitors, and PM{sub 2.5} light scattering extinction coefficient as measured by nephelometer. During the course of the project, measurement intercomparison data were developed for these instruments and several complementary measurements at the site. The report details the instrument set and operating procedures and describes the resulting data. Report subsections present an overview summary of the data, followed by detailed description of the systematic time behavior of PM{sub 2.5} and other specific particulate size fractions. Specific subsections are included for particle size distribution, light scattering, and particle sulfate data. The final subsection addresses application of the measurements to the practical questions of fine PM generation and transport, source attribution, and PM{sub 2.5} management strategies.
Date: May 31, 2003
Creator: Williamson, Ashley
Partner: UNT Libraries Government Documents Department
open access

Biochemistry of Dissimilatory Sulfur Oxidation

Description: The long term goals of this research were to define the substrate oxidation pathways, the electron transport mechanisms, and the modes of energy conservation employed during the dissimilatory oxidation of sulfur practiced by various species of the thiobacilli. Specific adhesion of the thiobacilli to elemental sulfur was studied by electrical impedance, dynamic light scattering, laser Doppler velocimetry, and optical trapping methods. The conclusion is that the thiobacilli appear to express specific receptors that enable the bacteria to recognize and adhere to insoluble sulfur. The enzyme tetrathionate oxidase was purified from two species of the thiobacilli. Extensive structural and functional studies were conducted on adenosine 5'-phosphosulfate reductase purified from cell-free extracts of Thiobacillus denitrificans. The kinetic mechanism of rhodanese was studied.
Date: May 30, 2003
Creator: Blake II, R.
Partner: UNT Libraries Government Documents Department
open access

Bioenergy Crop Breeding and Production Research in the Southeast, Final Report for 1996 to 2001

Description: Switchgrass (Panicum virgatum L.) is a native grass species to much of the US. It has shown great potential for use in production of fuel ethanol from cellulosic biomass (Lynd et al., 1991). Work in Alabama demonstrated very high dry matter yields can be achieved with switchgrass (Maposse et al. 1995) in the southeastern US. Therefore, this region is thought to be an excellent choice for development of a switchgrass cropping system where farmers can produce the grass for either biomass or forage. Another report has shown success with selection and breeding to develop high yielding germplasm from adapted cultivars and ecotypes of switchgrass (Moser and Vogel 1995). In the mid 1990s, however, there was little plant breeding effort for switchgrass with a potential for developing a cultivar for the southeast region. The main goal of the project was to develop adaptive, high-yielding switchgrass cultivars for use in cropping systems for bioenergy production in the southeastern US. A secondary objective was to assess the potential of alternate herbaceous species such as bermudagrass (Cynodon dactylon L.), bahiagrass (Paspalum notatum Flugge.), and napiergrass (Pennisetum purpureum Schumach.) that may compete with switchgrass for herbaceous bioenergy production in the southeast. During the conduct of the project, another goal of developing molecular markers useful for genetic mapping was added. The ''lowland'' cultivars, Alamo and Kanlow, were found to be the highest yielding switchgrass cultivars. Although most summers during the project period were hot and dry, their annual dry matter yield continue to outperform the best ''upland'' cultivars such as Cave-in-Rock, Shawnee, NE Late, and Trailblazer. The use of a breeding procedure based on the ''honeycomb design'' and multi-location progeny testing, coupled with the solid heritability and genetic gain estimates for dry matter yield in lowland type switchgrass germplasm, indicated excellent potential to isolate parental genotypes …
Date: May 30, 2003
Creator: Bouton, J. H.
Partner: UNT Libraries Government Documents Department
open access

Bioterrorism: Information Technology Strategy Could Strengthen Federal Agencies' Abilities to Respond to Public Health Emergencies

Description: A letter report issued by the General Accounting Office with an abstract that begins "The October 2001 anthrax attacks, the recent outbreak of the virulent Severe Acute Respiratory Syndrome (SARS), and increased awareness that terrorist groups may be capable of releasing life-threatening biological agents have prompted efforts to improve our nation's preparedness for, and response to, public health emergencies--including bioterrorism. GAO was asked, among other things, to identify federal agencies information technology (IT) initiatives to support our nation's readiness to deal with bioterrorism. Specifically, we compiled an inventory of such activities, determined the range of these coordination activities with other agencies, and identified the use of health care standards in these efforts."
Date: May 30, 2003
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department
open access

Defense Trade: Report and Recommendations of the Defense Offsets Commission Still Pending

Description: A letter report issued by the General Accounting Office with an abstract that begins "Export sales of defense-related products often include "offsets"-- industrial and commercial benefits, such as technology transfer, which U.S. companies provide to foreign governments as incentives or conditions for purchasing military goods and services. Over the past decade, offsets have increased and in 1998, they totaled about $3 billion per year. In December 2000, GAO reported that countries are becoming increasingly sophisticated in their use of offsets to achieve regional industrial and employment goals. In 1999, Congress established a National Commission to report on the extent and nature of offsets in international defense trade by October 2001. The Director of the Office of Management and Budget (OMB) was designated chair of the Commission. Congress also required the President to report, within 90 days after the Commission's final report, on the feasibility and desirability of seeking a multilateral treaty with international trading partners on standards for use of defense offsets. GAO's report responds to the congressional mandate for GAO to monitor and periodically report on the President's progress in reaching a multilateral treaty."
Date: May 30, 2003
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department
open access

Effects of Self Irradiation from 238Pu on Candidate Ceramics for Plutonium Immobilization

Description: In this document, we describe the results of radiation damage testing and characterization for specimens that were resintered to re-establish crystallinity. The phases in these specimens have become amorphous from radiation induced damage over the 8 months since sintering.
Date: May 30, 2003
Creator: Strachan, Denis M.; Scheele, Randall D.; Kozelisky, Anne E. & Sell, Rachel L.
Partner: UNT Libraries Government Documents Department
open access

Elderly Housing: Project Funding and Other Factors Delay Assistance to Needy Households

Description: A letter report issued by the General Accounting Office with an abstract that begins "According to the Department of Housing and Urban Development (HUD), the most widespread and urgent housing problem facing elderly households is affordability. About 3.3 million elderly renter households in the United States have very low incomes (50 percent or less of median area income). The Section 202 Supportive Housing for the Elderly Program provides capital advances (grants) to nonprofit organizations to develop affordable rental housing exclusively for these households. GAO was asked to determine the role of the Section 202 program in addressing the need for affordable elderly housing and the factors affecting the timeliness of approving and constructing new projects."
Date: May 30, 2003
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department
open access

Electronic Banking: The Check Truncation Issue

Description: If all checks were replaced by electronic transactions, the exact cost savings would still be unknown, because estimates of the cost of using a check and the number of checks written each year remain in dispute. Consequently, estimates of cost savings range from $1.4 billion annually for truncation alone to $68 billion for replacing checks with electronic payments. A significant part of the savings comes from eliminating the handling, sorting, and physically transporting of checks to the paying bank. To clear checks electronically, banks must negotiate processing agreements thatmake it unnecessary to physically present the paper check. Since the benefits are not uniformly dispersed among the participants, banks have found it difficult to obtain these agreements, thus constraining the widespread adoption of electronic check clearing.
Date: May 30, 2003
Creator: Eubanks, Walter W.
Partner: UNT Libraries Government Documents Department
open access

The Endangered Species Act (ESA), Migratory Bird Treaty Act (MBTA), and Department of Defense (DOD) Readiness Activities: Current Law and Legislative Proposals

Description: This report provides a brief overview of how the Endangered Species Act (ESA)1 and the Migratory Bird Treaty Act (MBTA)2 and their relevant regulations may apply to military training and readiness activities of the Department of Defense (DOD). Military activities may “take” protected creatures directly (e.g,. killing with ordnance during rifle, gunnery or assault drills), or might destroy habitat (e.g., artillery or bombing practices), even if these results are not the purpose of the activities. The applicability of the MBTA and ESA to military readiness activities has been controversial recently and legislation has been enacted in both the 107th and 108th Congresses on these topics.
Date: May 30, 2003
Creator: Baldwin, Pamela
Partner: UNT Libraries Government Documents Department
open access

Energy Policy: The Continuing Debate

Description: On April 10, 2003, the House passed comprehensive energy legislation, H.R. 6 (247- 175). The bill was a composite of four measures – H.R. 39, reported from the House Committee on Resources, H.R. 238, marked up by the House Science Committee, H.R. 1531, reported from Ways and Means, and an unnumbered bill reported out of the Energy and Commerce Committee. Unlike comprehensive energy legislation (H.R. 4) debated in the 107th Congress, H.R. 6 includes a section on electricity which has stirred some controversy. H.R. 6 would provide authorization for exploration and development of the Arctic National Wildlife Refuge (ANWR).
Date: May 30, 2003
Creator: Bamberger, Robert L.
Partner: UNT Libraries Government Documents Department
open access

Environmental Streamlining Provisions in the Transportation Equity Act for the 21st Century: Status of Implementation

Description: At the state and local level, many observers have expressed long-standing concerns over delays, duplication of effort, and additional costs frequently associated with the environmental review process for highway projects that must be completed under the National Environmental Policy Act of 1969 (NEPA, P.L. 91-190). To address these concerns, the Transportation Equity Act for the 21st Century (TEA21, P.L. 105-178), enacted in 1998, requires the Federal Highway Administration(FHWA) to streamline the environmental review process for highway projects.
Date: May 30, 2003
Creator: Luther, Linda G. & Bearden, David M.
Partner: UNT Libraries Government Documents Department
open access

Final Report: California water resources research and applicationscenter

Description: The California Water Resources RESAC objectives were toutilize NASA data to provide state-of-the-art real-time and forecastinformation (observation and simulation) on hydroclimate, water quantityand quality, and runoff related hazards to water resources managers(e.g., NWS, CA Dept. of Water Resources, USBR), the insurance industry,emergency response agencies, policy decision-makers, and the generalpublic. In addition, the RESAC acts as an umbrella organization fosteringgrowing collaborations and partnerships. It was built on the foundationestablished through the U.S. Global Change Research Program and theNational and California Assessments. It is designed to support theongoing regional and national assessment process by improving ourunderstanding of specific regional features of the climate system and itsimpacts, and facilitating the dissemination of these results throughdata, publications, and outreach.The California Water Resources RESACproduces three types of regional climate products that are enhanced byincorporation of NASA satellite data: (1) short-term (2-3 day) weatherand streamflow forecasts, (2) seasonal hydroclimate, and (3) long-termclimate change scenarios and hydrologic impacts. Our team has built anexcellent record in providing quantitative precipitation and streamflowforecasts to the water resources and weather prediction communities. Wehave been working with scientists from various University of Californiainstitutions and government agencies to improve weather and streamflowpredictions and studies of regional hydroclimate, and its impacts onwater resources, the environment, and the economy.
Date: May 30, 2003
Creator: Miller, Norman L.
Partner: UNT Libraries Government Documents Department
open access

Human Capital: Opportunities to Improve Executive Agencies' Hiring Processes

Description: A letter report issued by the General Accounting Office with an abstract that begins "Improving the federal hiring process is critical, as the number of new hires is expected to increase substantially. Federal agencies are responsible for their hiring processes, but must generally comply with applicable Office of Personnel Management (OPM) rules and regulations. Congressional requesters asked GAO to identify federal hiring obstacles, provide examples of innovative hiring practices, and identify opportunities for improvement. To address these issues, GAO interviewed the human resources directors in 24 largest departments and agencies, analyzed the hiring practices of five federal executive branch agencies, and reviewed OPM's role in the hiring process."
Date: May 30, 2003
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department
open access

Improved Miscible Nitrogen Flood Performance Utilizing Advanced Reservoir Characterization and Horizontal Laterals in a Class I Reservoir - East Binger (Marchand) Unit Quarterly Report

Description: Implementation of the work program of Budget Period 2 of the East Binger Unit (''EBU'') DOE Project continues. Significant advances with the reservoir simulation model have led to changes in the program. One planned horizontal well location, EBU 44-3H, has been eliminated from the program, and another, EBU 45-3H, has been deferred, and may be replaced by a vertical well or completely eliminated at a future date. A new horizontal well location, EBU 63-2H, has been added. EBU 74G-2, the one new injection well planned for the project, was completed and brought on production. It will be produced for a period of time before converting it to injection. Performance is exceeding expectations. Work also continued on projects aimed at increasing injection in the pilot area. EBU 65-1 was converted to injection service. The project to add compression and increase injection capacity at the nitrogen management facility is nearing completion. Additional producer-to-injector conversions will follow.
Date: May 30, 2003
Creator: Sinner, Joe
Partner: UNT Libraries Government Documents Department
open access

The Influence of MSI (Metal-Support Interactions) and the Solvent in Liquid-Phase Reactions

Description: Results were repeatedly obtained that were consistent with a hypothesis proposed at the beginning of this program, i.e., due to Metal-Support Interactions (MSI), unique active sites can be created in the metal-support interfacial region to enhance activity and improve selectivity in certain types of reactions, especially those involving the hydrogenation of carbonyl and unsaturated C=C bonds. Higher turnover frequencies (TOF-molecule/s/site) and increased selectivity for C=O bond versus C=C bond hydrogenation was established in the hydrogenation reactions of: acetone, crotonaldehyde, acetophenone, phenylethanol, acetylcyclohexane, benzaldehyde, benzyl alcohol, phenylacetaldehyde and citral over Pt/TiO{sub 2} MSI catalysts. Higher rates of hydrogenation benzene, toluene and xylene could be obtained over certain supported Pt and Pd catalysts. Au/TiO{sub 2} catalysts were developed that were active for CO hydrogenation at subambient temperatures. The influence of support and metal crystallite size were established for the adsorption of H{sub 2}, CO and O{sub 2} on families of Pt and Pd catalysts.
Date: May 30, 2003
Creator: Vannice, M. A.
Partner: UNT Libraries Government Documents Department
open access

Information Security: Progress Made, but Weaknesses at the Internal Revenue Service Continue to Pose Risks

Description: A letter report issued by the General Accounting Office with an abstract that begins "As part of its annual audits of IRS's financial statements, GAO assessed the effectiveness of information security controls at certain IRS facilities and over certain specific applications--controls meant to protect IRS's information systems and taxpayer data. Because the detailed reports that followed these reviews contained sensitive information and could be detrimental to the government if released to the public, they were issued only to IRS and congressional requesters. This public report is based on 18 such reports issued during the 3-year period ending July 31, 2002. Although it does not identify specific IRS facilities or applications, the report does provide GAO's assessment of the overall effectiveness of IRS's information security."
Date: May 30, 2003
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen