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Agriculture: A List of Websites (open access)

Agriculture: A List of Websites

This list provides a sampling of the rapidly proliferating number of agricultural resources available on the Internet. It is not intended to be exhaustive. It is divided into 24 main categories and 16 subcategories.
Date: August 15, 2002
Creator: Canada, Carol
Object Type: Report
System: The UNT Digital Library
INNOVATAIVE METHODOLOGY FOR DETECTION OF FRACTURE-CONTROLLED SWEET SPOTS IN THE NORTHERN APPALACHIAN BASIN (open access)

INNOVATAIVE METHODOLOGY FOR DETECTION OF FRACTURE-CONTROLLED SWEET SPOTS IN THE NORTHERN APPALACHIAN BASIN

In the structure task, for this reporting period, the authors also edited and revised the map that displays the modified rose diagrams for the data they collected and reduced along the east side of Seneca Lake. They also revised the N-S transect that displays the frequency of ENE-striking fractures, and constructed a new N-S transect that shows the frequency of E-striking fractures. This transect compliments the earlier transect they constructed for fracture frequency of ENE-striking fractures. Significantly, the fracture frequency transect for E-W fractures shows a spike in fracture frequency in the region of the E-striking Firtree anticline that is observed on seismic reflection sections. The ENE fracture set does not exhibit an unusually high fracture frequency in this area. In contrast, the fracture frequency of the ENE-striking set is anomalously high in the region of the Trenton/Black River grabens. They have nearly completed reducing the data they collected from a NNW-SSE transect on the west side of Cayuga Lake and they have constructed modified rose diagrams for most sites. Structure contour maps and isopach maps have been revised based on additional well log analyses. Except for the Glodes Corners Field, the well spacing generally remains insufficient to identify faults …
Date: June 30, 2002
Creator: Jacobi, Robert & Fountain, John
Object Type: Report
System: The UNT Digital Library
INNOVATIVE METHODOLOGY FOR DETECTION OF FRACTURE-CONTROLLED SWEET SPOTS IN THE NORTHERN APPALACHIAN BASIN (open access)

INNOVATIVE METHODOLOGY FOR DETECTION OF FRACTURE-CONTROLLED SWEET SPOTS IN THE NORTHERN APPALACHIAN BASIN

In the structure task, we completed reducing the data we had collected from a N-S transect on the east of Seneca Lake. We have calculated the fracture frequency for all the fracture sets at each site, and constructed modified rose diagrams that summarize the fracture attributes at each site. These data indicate a N-striking fault near the southeastern shore of Seneca Lake, and also indicate NE and ENE-trending FIDs and faults north of Valois. The orientation and existence of the ENE-striking FIDs and faults are thought to be guided by faults in the Precambrian basement; these basement faults apparently were sufficiently reactivated to cause faulting in the Paleozoic section. Other faults are thrust ramps above the Silurian salt section that were controlled by a far-field Alleghanian stress field. Structure contour maps and isopach maps have been revised based on additional well log analyses. Except for the Glodes Corners Field, the well spacing generally is insufficient to definitively identify faults. However, relatively sharp elevational changes east of Keuka Lake support the contention that faults occur along the east side of Keuka Lake. Outcrop stratigraphy along the east side of Seneca Lake indicates that faults and gentle folds can be inferred from …
Date: January 30, 2002
Creator: Jacobi, Robert & Fountain, John
Object Type: Report
System: The UNT Digital Library
Using FEP's List and a PA Methodology for Evaluating Suitable Areas for the LLW Repository in Italy (open access)

Using FEP's List and a PA Methodology for Evaluating Suitable Areas for the LLW Repository in Italy

In Italy following a referendum held in 1987, nuclear energy has been phased out. Since 1998, a general site selection process covering the whole Italian territory has been under way. A GIS (Geographic Information System) methodology was implemented in three steps using the ESRI Arc/Info and Arc/View platforms. The screening identified approximately 0.8% of the Italian territory as suitable for locating the LLW Repository. 200 areas have been identified as suitable for the location of the LLW Repository, using a multiple exclusion criteria procedure (1:500,000), regional scale (1:100.000) and local scale (1:25,000-1:10,000). A methodology for evaluating these areas has been developed allowing, along with the evaluation of the long term efficiency of the engineered barrier system (EBS), the characterization of the selected areas in terms of physical and safety factors and planning factors. The first step was to identify, on a referenced FEPs list, a group of geomorphological, geological, hydrogeological, climatic and human behavior caused process and/or events, which were considered of importance for the site evaluation, taking into account the Italian situation. A site evaluation system was established ascribing weighted scores to each of these processes and events, which were identified as parameters of the new evaluation system. The …
Date: February 26, 2002
Creator: Risoluti, P.; Ciabatti, P. & Mingrone, G.
Object Type: Article
System: The UNT Digital Library
Determination of Importance Evaluation for Exploratory Studies Facility (ESF) Subsurface Testing Activities (open access)

Determination of Importance Evaluation for Exploratory Studies Facility (ESF) Subsurface Testing Activities

This Determination of Importance Evaluation (DIE) applies to the Subsurface Exploratory Studies Facility (ESF), encompassing the Topopah Spring (TS) Loop from Station 0+00 meters (m) at the North Portal to breakthrough at the South Portal (approximately 78+77 m), and ancillary test and operation support areas including the Enhanced Characterization of the Repository Block (ECRB) Cross Drift. This evaluation applies specifically to site characterization testing activities ongoing and planned in the Subsurface ESF. ESF site characterization activities are being performed to obtain the information necessary to determine whether the Yucca Mountain Site is suitable as a geologic repository for spent nuclear fuel and high-level radioactive waste. A more detailed description of these testing activities is provided in Section 6 of this DIE. Generally, the construction and operation of excavations associated with these testing activities are evaluated in the DIE for the Subsurface ESF (CRWMS M&O 1999a) and the DIE for the ESF ECRB Cross Drift (CRWMS M&O 2000a). The scope of this DIE also entails the proposed Unsaturated Zone (UZ) Transport Test at Busted Butte. Although, not a part of the TS Loop or ECRB Cross Drift, the associated testing activities are Subsurface testing activities. Busted Butte is located to the …
Date: July 22, 2002
Creator: Goodin, S.
Object Type: Report
System: The UNT Digital Library
Weapons of Mass Destruction: U.N. Confronts Significant Challenges in Implementing Sanctions against Iraq (open access)

Weapons of Mass Destruction: U.N. Confronts Significant Challenges in Implementing Sanctions against Iraq

A letter report issued by the General Accounting Office with an abstract that begins "United Nations sanctions were first imposed in August 1990 following Iraq's invasion of Kuwait. In 1991, the Security Council established sanctions to stop Iraq from acquiring or developing biological, chemical, and nuclear weapons. To achieve this, the Security Council prohibited all nations from buying Iraqi oil or selling the country any commodities except for food and medicine. It further established a weapons inspection regime to ensure that Iraq destroyed its weapons of mass destruction and stopped its weapons programs. Concerned about the humanitarian need of the Iraqi people, in 1995 the Security Council established a controls program for Iraq's oil sales that allows for the purchase of food, medicine, and essential civilian goods (the oil for food program). With international support for the sanctions eroding, in 2001 the Security Council passed a new sanctions resolution to address humanitarian concerns while keeping Iraq from rebuilding its weapons systems. Although the U.N. controlled $51 billion of Iraq's oil revenues from 1997 to 2001, Iraq earned an additional $6.6 billion in illegal revenue from oil smuggling and surcharges during the same time. Further, although the sanctions prohibit Iraq from …
Date: May 23, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
USDOE Top-of-Rail Lubricant Project (open access)

USDOE Top-of-Rail Lubricant Project

Lubrication of wheel/rail systems has been recognized for the last two decades as a very important issue for railroads. Energy savings and less friction and wear can be realized if a lubricant can be used at the wheel/rail interface. On the other hand, adverse influences are seen in operating and wear conditions if improper or excessive lubrication is used. Also, inefficiencies in lubrication need to be avoided for economic and environmental reasons. The top-of-rail (TOR) lubricant concept was developed by Texaco Corporation to lubricate wheels and rails effectively and efficiently. Tranergy Corporation has been developing its SENTRAEN 2000{trademark} lubrication system for the last ten years, and this revolutionary new high-tech on-board rail lubrication system promises to dramatically improve the energy efficiency, performance, safety, and track environment of railroads. The system is fully computer-controlled and ensures that all of the lubricant is consumed as the end of the train passes. Lubricant quantity dispensed is a function of grade, speed, curve, and axle load. Tranergy also has its LA4000{trademark} wheel and rail simulator, a lubrication and traction testing apparatus. The primary task of this project was collecting and analyzing the volatile and semivolatile compounds produced as the lubricant was used. The volatile …
Date: February 1, 2002
Creator: Alzoubi, Mohumad F.; Fenske, George R.; Erck, Robert A. & Boparai, Amrit S.
Object Type: Report
System: The UNT Digital Library
Export Controls: Processes for Determining Proper Control of Defense-Related Items Needs Improvement (open access)

Export Controls: Processes for Determining Proper Control of Defense-Related Items Needs Improvement

A letter report issued by the General Accounting Office with an abstract that begins "The U.S. government controls the export of defense-related items to minimize the risk such exports may pose to its interests. The U.S. export control system is primarily divided between two regulatory regimes, one managed by the Department of State for defense items and another managed by the Department of Commerce for dual-use items that have both military and commercial applications. Companies are responsible for determining which department to use and what requirements apply when exporting their items, but can obtain government assistance through two different processes. If companies have determined that their items are Commerce-controlled but are uncertain of export licensing requirements, they may request a classification from Commerce through the commodity classification process. Commerce can refer classification requests to State and the Department of Defense to confirm that the items are Commerce-controlled. However, if companies are unsure of which department has jurisdiction over their items, they can request a determination through the commodity jurisdiction process from State, which consults with Commerce and Defense. In implementing the commodity classification process, Commerce has improperly classified some State-controlled items as Commerce-controlled and has not adhered to regulatory time …
Date: September 20, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Final Technical Report: Response of Mediterranean-Type Ecosystems to Elevated Atmospheric CO2 and Associated Climate Change (open access)

Final Technical Report: Response of Mediterranean-Type Ecosystems to Elevated Atmospheric CO2 and Associated Climate Change

This research incorporated an integrated hierarchical approach in space, time, and levels of biological/ecological organization to help understand and predict ecosystem response to elevated CO{sub 2} and concomitant environmental change. The research utilized a number of different approaches, and collaboration of both PER and non-PER investigators to arrive at a comprehensive, integrative understanding. Central to the work were the CO{sub 2}-controlled, ambient Lit, Temperature controlled (CO{sub 2}LT) null-balance chambers originally developed in the arctic tundra, which were re-engineered for the chaparral with treatment CO{sub 2} concentrations of from 250 to 750 ppm CO{sub 2} in 100 ppm increments, replicated twice to allow for a regression analysis. Each chamber was 2 meters on a side and 2 meters tall, which were installed over an individual shrub reprouting after a fire. This manipulation allowed study of the response of native chaparral to varying levels of CO{sub 2}, while regenerating from an experimental burn. Results from these highly-controlled manipulations were compared against Free Air CO{sub 2} Enrichment (FACE) manipulations, in an area adjacent to the CO{sub 2}LT null balance greenhouses. These relatively short-term results (5-7 years) were compared to long-term results from Mediterranean-type ecosystems (MTEs) surrounding natural CO{sub 2} springs in northern Italy, …
Date: August 15, 2002
Creator: Oechel, Walter C
Object Type: Report
System: The UNT Digital Library
The Enhanced Plan for Features, Events, and Processes (FEPS) at Yucca Mountain (open access)

The Enhanced Plan for Features, Events, and Processes (FEPS) at Yucca Mountain

A performance assessment is required to demonstrate compliance with the post-closure performance objectives for the Yucca Mountain Project (YMP), as stated in 10 CFR Part 63.1 13 (66 FR 55732, p. 55807). A performance assessment is defined in 10 CFR 63.2 (66 FR 55732, p. 55794) as an analysis that: (1) identifies the features, events, and processes (FEPs) that might affect the potential geologic repository; (2) examines the effects of those FEPs upon the performance of the potential geologic repository; and (3) estimates the expected dose incurred by a specified reasonably maximally exposed individual as a result of releases caused by significant FEPs. The performance assessment must also provide the technical basis for inclusion or exclusion of specific FEPs in the performance assessment as stated in 10 CFR 63.114 (66 FR 55732, p. 55807). An initial approach for FEP development, in support of the Total System Performance Assessment for the Site Recommendation (TSPA-SR) (CRWMS M&O 2000e), was documented in Freeze et al. (2001). The development of a comprehensive list of FEPs potentially relevant to the post-closure performance of the potential Yucca Mountain repository is an ongoing, iterative process based on site-specific information, design, and regulations. Although comprehensiveness of the FEPs …
Date: March 25, 2002
Creator: Freeze, G.
Object Type: Report
System: The UNT Digital Library
Endangered Species Act of 1973 (open access)

Endangered Species Act of 1973

The Endangered Species Act (ESA) provides a program for the conservation of threatened and endangered plants and animals and the habitats in which they are found. The U.S. Fish and Wildlife Service (FWS) of the Department of the Interior maintains a worldwide list which, as of Feb. 20, 2008, included 1574 endangered species (599 are plants) and 351 threatened species (148 are plants). Species include birds, insects, fish, reptiles, mammals, crustaceans, flowers, grasses, and trees. Anyone can petition FWS to include a species on this list. The law requires federal agencies, in consultation with the U.S. Fish and Wildlife Service and/or the U.S. National Oceanic and Atmospheric Administration Fisheries Service, to ensure that actions they authorize, fund, or carry out are not likely to jeopardize the continued existence of any listed species or result in the destruction or adverse modification of designated critical habitat of such species. The law also prohibits any action that causes a "taking" of any listed species of endangered fish or wildlife. Likewise, import, export, interstate, and foreign commerce of listed species are all generally prohibited.
Date: January 24, 2002
Creator: United States. Congress. House.
Object Type: Text
System: The UNT Digital Library
Program Plan for Acquiring and Examining Naturally Aged Materials and Components from Nuclear Reactors (open access)

Program Plan for Acquiring and Examining Naturally Aged Materials and Components from Nuclear Reactors

This project was funded through the Nuclear Plant Optimization Program (NEPO)to develop an integrated plan to indentify aging issues that can be effectively addressed by investigating the condition of naturally aged components, materials,and structures (CMSs)from nuclear power plants (NPPs. As operating periods for the NPPs increase, there is a need to access selected CMSs for continuing assurance that aging issues are understood and effectively managed; also, that benchmarking of existing models is updated. A preliminary list of aging CMSs is provided for selection of candidates as NPPs are shut down or as opportunities arise to obtain CMS data from operating plants. The list is subject to revisions, based on consensus judgements regarding the most important aging issues. Further updates will arise as certain aging issues are resolved and as new issues may emerge.
Date: July 10, 2002
Creator: Johnson, A. Burton; Sundaram, S. K. & Garner, Francis A.
Object Type: Report
System: The UNT Digital Library
SEC Operations: Implications of Alternative Funding Structures (open access)

SEC Operations: Implications of Alternative Funding Structures

A letter report issued by the General Accounting Office with an abstract that begins "GAO studied the implications of converting the Securities and Exchange Commission (SEC) to a self-funded entity. Congress has created a range of self-funding structures, or other sources of funding, other than appropriations for the Department of the Treasury's general fund. The variations among these agencies depend on how and when Congress makes the fees available to an agency and how much flexibility Congress gives an agency in using its collected fees without further legislative action. Moving SEC to a more self-controlled funding structure has implications for two important areas. First, SEC would have more control over its own budget and funding level, which some SEC and industry officials believe may better enable SEC to address its increasing workload and some of its human capital challenges, such as its ability to recruit and retain quality staff. The second result would be a loss of checks and balances currently provided by the federal budget and appropriations processes. Moving SEC to a self-controlled funding structure would diminish congressional and executive branch oversight. On the other hand, the congressional authorizing committees would maintain or else could choose to increase their …
Date: July 16, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
High Temperature Materials Laboratory Fourteenth Annual Report: October 2000 through September 2001 (open access)

High Temperature Materials Laboratory Fourteenth Annual Report: October 2000 through September 2001

The HTML User Program continued to work with industrial, academic, and governmental users this year, accepting 92 new projects and developing 48 new user agreements. Table 1 presents the breakdown of these statistics. Figure 1 depicts the continued growth in user agreements and user projects. You will note that the total number of HTML proposals has now exceeded 1000. Also, the large number of new agreements bodes well for the future. At the end of the report, we present a list of proposals to the HTML and a list of agreements between HTML and universities and industries, broken down by state. Program highlights this year included several outstanding user projects (some of which are highlighted in later sections), the annual meeting of the HTML Programs Senior Advisory Committee, and approval by ORNL for the construction of a building to house our new aberration-corrected electron microscope (ACEM) and several other sensitive electron and optical instruments.
Date: May 16, 2002
Creator: Pasto, A.E.
Object Type: Report
System: The UNT Digital Library
Photovoltaic Manufacturing Cost and Throughput Improvements for Thin Film CIGS-Based Modules: Final Technical Report, July 1998 -- September 2001 (open access)

Photovoltaic Manufacturing Cost and Throughput Improvements for Thin Film CIGS-Based Modules: Final Technical Report, July 1998 -- September 2001

This report describes the marked improvements made of the production line under the PVMaT program: successfully developed a high-speed, all-laser, monolithic integration process for CIGS-based modules on polyimide substrates; exceeded PVMaT goals for scribing rate and total interconnect width; developed robust, well-controlled techniques for selective scribing; improved CIGS evaporation sources to allow uniform, controllable delivery; completed foundation required to integrate higher CIGS deposition rates into the production line; developed well-controlled Se delivery system to minimize Se consumption; successfully integrated the parallel-detector spectroscope ellipsometer (PDSE) into a production CIGS deposition chamber; collected useful, in-situ data with PDSE; validated the performance of the X-ray fluorescometry (XRF) sensor in the production CIGS deposition chamber; and successfully incorporated the XRF sensor into the control architecture of the production CIGS deposition chamber .
Date: April 1, 2002
Creator: Britt, J.
Object Type: Report
System: The UNT Digital Library
Noncontiguous I/O through PVFS. (open access)

Noncontiguous I/O through PVFS.

With the tremendous advances in processor and memory technology, I/O has risen to become the bottleneck in high-performance computing for many applications. The development of parallel file systems has helped to ease the performance gap, but I/O still remains an area needing significant performance improvement. Research has found that noncontiguous I/O access patterns in scientific applications combined with current file system methods to perform these accesses lead to unacceptable performance for large data sets. To enhance performance of noncontiguous I/O, we have created list I/O, a native version of noncontiguous I/O. We have used the Parallel Virtual File System (PVFS) to implement our ideas. Our research and experimentation shows that list I/O outperforms current noncontiguous I/O access methods in most I/O situations and can substantially enhance the performance of real-world scientific applications.
Date: August 12, 2002
Creator: Ching, A.; Choudhary, A.; Liao, W.-K.; Ross, R. & Gropp, W.
Object Type: Article
System: The UNT Digital Library
Defense Trade: Lessons to Be Learned from the Country Export Exemption (open access)

Defense Trade: Lessons to Be Learned from the Country Export Exemption

A letter report issued by the General Accounting Office with an abstract that begins "To control the export of defense items, the U.S. government requires exporters to obtain a license from the State Department. A license is not required to export many defense items to Canada, currently the only country-specific exemption to the licensing requirement. In May 2000, the U.S. government announced the Defense Trade Security Initiative, which included a proposal to grant Canadian-like export licensing exemptions to other qualified countries. Since the initiative was announced, the State Department has been negotiating such exemptions with the United Kingdom and Australia. Exporters have been implementing the Canadian exemption inconsistently. Moreover, some exporters are interpreting reporting requirements about the use of the exemption differently. The U.S. government has mechanisms in place to reduce the risk of defense items being inappropriately exported, but there are associated limitations. U.S. Customs officials attributed these enforcement weaknesses to a lack of information and resources, including inspectors to staff ports. In addition, there are competing demands on the agency, which include the prevention of terrorism, and the interdiction of illicit drugs, illegal currency, and stolen vehicles. Experience with the Canadian exemption shows that three areas need to …
Date: March 29, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Steady-State Simulation of Steam Reforming of INEEL Tank Farm Waste (open access)

Steady-State Simulation of Steam Reforming of INEEL Tank Farm Waste

A steady-state model of the Sodium-Bearing Waste steam reforming process at the Idaho National Engineering and Environmental Laboratory has been performed using the commercial ASPEN Plus process simulator. The preliminary process configuration and its representation in ASPEN are described. As assessment of the capability of the model to mechanistically predict product stream compositions was made, and fidelity gaps and opportunities for model enhancement were identified, resulting in the following conclusions: 1) Appreciable benefit is derived from using an activity coefficient model for electrolyte solution thermodynamics rather than assuming ideality (unity assumed for all activity coefficients). The concentrations of fifteen percent of the species present in the primary output stream were changed by more than 50%, relative to Electrolyte NRTL, when ideality was assumed; 2) The current baseline model provides a good start for estimating mass balances and performing integrated process optimization because it contains several key species, uses a mechanistic electrolyte thermodynamic model, and is based on a reasonable process configuration; and 3) Appreciable improvement to model fidelity can be realized by expanding the species list and the list of chemical and phase transformations. A path forward is proposed focusing on the use of an improved electrolyte thermodynamic property method, …
Date: August 1, 2002
Creator: Nichols, Todd Travis; Taylor, Dean Dalton; Wood, Richard Arthur & Barnes, Charles Marshall
Object Type: Report
System: The UNT Digital Library
Steady-State Simulation of Steam Reforming of INEEL Tank Farm Waste (open access)

Steady-State Simulation of Steam Reforming of INEEL Tank Farm Waste

A steady-state model of the Sodium-Bearing Waste steam reforming process at the Idaho National Engineering and Environmental Laboratory has been performed using the commercial ASPEN Plus process simulator. The preliminary process configuration and its representation in ASPEN are described. As assessment of the capability of the model to mechanistically predict product stream compositions was made, and fidelity gaps and opportunities for model enhancement were identified, resulting in the following conclusions: (1) Appreciable benefit is derived from using an activity coefficient model for electrolyte solution thermodynamics rather than assuming ideality (unity assumed for all activity coefficients). The concentrations of fifteen percent of the species present in the primary output stream were changed by more than 50%, relative to Electrolyte NRTL, when ideality was assumed; (2) The current baseline model provides a good start for estimating mass balances and performing integrated process optimization because it contains several key species, uses a mechanistic electrolyte thermodynamic model, and is based on a reasonable process configuration; and (3) Appreciable improvement to model fidelity can be realized by expanding the species list and the list of chemical and phase transformations. A path forward is proposed focusing on the use of an improved electrolyte thermodynamic property method, …
Date: August 15, 2002
Creator: Nichols, T. T.; Taylor, D. D.; Wood, R. A. & Barnes, C. M.
Object Type: Report
System: The UNT Digital Library
Export Controls: Department of Commerce Controls over Transfers of Technology to Foreign Nationals Need Improvement (open access)

Export Controls: Department of Commerce Controls over Transfers of Technology to Foreign Nationals Need Improvement

A letter report issued by the General Accounting Office with an abstract that begins "To protect its national security and foreign policy interests, the United States controls exports of civilian technologies that have military uses. U.S. firms may be required to obtain a license from the Department of Commerce before exporting these "dual-use" technologies from the United States to many other countries, including countries of concern. Since Commerce regulations also deem domestic transfers of controlled dual-use technologies to citizens of these countries to be exports, Commerce may require firms that employ foreign nationals working with these technologies in this country to obtain "deemed" export licenses. The firms should, in many cases, hold a deemed export license, and the foreign nationals should have an appropriate visa classification, such as an H-1B specialized employment classification. Commerce issues deemed export licenses to firms that employ or sponsor foreign nationals after consulting the Departments of Defense, State, and Energy. Deemed export licenses are generally valid for 2 years and comprise almost 10 percent of all export licenses approved by Commerce. In fiscal year 2001, Commerce approved 822 deemed export license applications and rejected 3. Most of the approved licenses allowed foreign nationals from countries …
Date: September 6, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Investigation of Lead Hydrolytic Polymerization and Interactions with Organic Ligands in the Soil/Sediment-Water Environment (open access)

Investigation of Lead Hydrolytic Polymerization and Interactions with Organic Ligands in the Soil/Sediment-Water Environment

The objective of this research was to investigate lead speciation in the soil/sediment-water environment and to better understand how the species affect lead mobility under different environmental conditions. The research involved both field soil and sediment samples as well as standard lead solutions. Field samples were fully characterized and extracted by aqueous and organic solvents. The results were compared and evaluated with the metal speciation model, MINTEQA2. Hydrolytic polymerization and organic complexation studies were conducted with standard lead solutions under controlled experimental conditions. Results of the field samples showed that pH, dissolved cations, ionic strength, dissolved organic matter, and nature of the soil/sediment matrix play major roles in the distribution and mobility of lead (Pb) from contaminated sites. In the aqueous equilibration experiment, the magnitude of Pb2+ solubilization was in the order of pH4>pH7>pH9. The results were in good agreement with MINTEQA2 predictions. An important finding of the research is the detection of Pb polymerization species under controlled experimental conditions. At pH 5.22, Pb polymeric species were formed at rate of 0.03 per day. The role of Pb complexation with organic matter was evaluated in both field and standard samples. Different methodologies showed three types of organically bound Pb. A …
Date: December 2002
Creator: Sanmanee, Natdhera
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Concentrations 41: Anri Sala (open access)

Concentrations 41: Anri Sala

Catalog of the exhibition, "Concentrations 41: Anri Sala", January 27 - May 19, 2002, held at the Dallas Museum of Art. Includes: list of works in the exhibition, essay, images, and biography of the artist.
Date: 2002-01-27/2002-05-19
Creator: Dallas Museum of Fine Arts
Object Type: Pamphlet
System: The Portal to Texas History
Disadvantaged Businesses: A Review of Federal Assistance (open access)

Disadvantaged Businesses: A Review of Federal Assistance

It is the policy of the federal government to encourage the development of small disadvantaged businesses (SDBs) owned by minorities and women. SDBs are statutorily defined as small businesses that are owned and controlled by socially and economically disadvantaged individuals who have been subjected to racial or ethnic prejudice or cultural bias and who have limited capital and credit opportunities. This report presents an overview of the major federal programs now in existence and indicates where interested persons can obtain further information about specific programs.
Date: January 14, 2002
Creator: Fauntroy, Michael K.
Object Type: Report
System: The UNT Digital Library
Acronyms, Initialisms, and Abbreviations (open access)

Acronyms, Initialisms, and Abbreviations

This document contains an updated list of common acronyms, initialisms, and abbreviations used at Sandia. It will be published in an electronic format only. It can be retrieved from HTTPS://wfsprod01.sandia.gov/groups/srn-uscitizens/documents/document/wfs048643.pdf.
Date: July 1, 2002
Creator: JOHNSON, DEBRA M.
Object Type: Report
System: The UNT Digital Library