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AN ACTIVE FRACTURE MODEL FOR UNSATURATED FLOW AND TRANSPORT (open access)

AN ACTIVE FRACTURE MODEL FOR UNSATURATED FLOW AND TRANSPORT

Fracture/matrix (F/M) interaction is a key factor affecting flow and transport in unsaturated fractured rocks. In classic continuum approaches (Warren and Root, 1963), it is assumed that flow occurs through all the connected fractures and is uniformly distributed over the entire fracture area, which generally gives a relatively large F/M interaction. However, fractures seem to have limited interaction with the surrounding matrix at Yucca Mountain, Nevada, as suggested by geochemical nonequilibrium between the perched water (resulting mainly from fracture flow) and pore water in the rock matrix. Because of the importance of the F/M interaction and related issues, there is a critical need to develop new approaches to accurately consider the interaction reduction inferred from field data at the Yucca Mountain site. Motivated by this consideration, they have developed an active fracture model based on the hypothesis that not all connected fractures actively conduct water in unsaturated fractured rocks.
Date: September 15, 1999
Creator: HUI-HAI LIU, GUDMUNDUR S. BODVARSSON AND CHRISTINE DOUGHTY
Object Type: Report
System: The UNT Digital Library
ALPS - advanced limiter-divertor plasma-facing systems. (open access)

ALPS - advanced limiter-divertor plasma-facing systems.

The Advanced Limiter-divertor Plasma-facing Systems (ALPS) program was initiated in order to evaluate the potential for improved performance and lifetime for plasma-facing systems. The main goal of the program is to demonstrate the advantages of advanced limiter/divertor systems over conventional systems in terms of power density capability, component lifetime, and power conversion efficiency, while providing for safe operation and minimizing impurity concerns for the plasma. Most of the work to date has been applied to free surface liquids. A multi-disciplinary team from several institutions has been organized to address the key issues associated with these systems. The main performance goals for advanced limiters and diverters are a peak heat flux of >50 MW/m{sup 2},elimination of a lifetime limit for erosion, and the ability to extract useful heat at high power conversion efficiency ({approximately}40%). The evaluation of various options is being conducted through a combination of laboratory experiments, modeling of key processes, and conceptual design studies. The current emphasis for the work is on the effects of free surface liquids on plasma edge performance.
Date: September 15, 1999
Creator: Allain, J. P.; Bastasz, R.; Brooks, J. N.; Evans, T.; Hassanein, A.; Luckhardt, S. et al.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 100, No. 152, Ed. 1 Wednesday, September 15, 1999 (open access)

Altus Times (Altus, Okla.), Vol. 100, No. 152, Ed. 1 Wednesday, September 15, 1999

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: September 15, 1999
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, September 15, 1999 (open access)

The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, September 15, 1999

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: September 15, 1999
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 77, No. 274, Ed. 1 Wednesday, September 15, 1999 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 77, No. 274, Ed. 1 Wednesday, September 15, 1999

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: September 15, 1999
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
California's Proposition 187: A Brief Overview (open access)

California's Proposition 187: A Brief Overview

This report provides a brief overview of California's proposition 187, a 1994 ballot initiative to deny illegal aliens state benefits and to require reporting of illegal alien applicants for benefits to federal immigration officials.
Date: September 15, 1999
Creator: Eig, Larry M.
Object Type: Report
System: The UNT Digital Library
Characterization of Fracture Patterns in the Geysers Geothermal Reservoir by Shear-wave Splitting (open access)

Characterization of Fracture Patterns in the Geysers Geothermal Reservoir by Shear-wave Splitting

The authors have analyzed the splitting of shear waves from microearthquakes recorded by a 16-station three-component seismic network at the Northwest Geysers geothermal field, Geysers, California, to determine the preferred orientation of subsurface fractures and cracks. Average polarization crack directions with standard deviation were computed for each station. Also, graphical fracture characterizations in the form of equal-area projections and rose diagrams were created to depict the results. The main crack orientations within the steam field are predominantly in the N10{degree}E to N50{degree}E direction, consistent with expected fracture directions in a pull-apart basin created by sub-parallel right-lateral strike-slip faults related to the San Andreas fault system. Time delays range from 15--60 ms, similar to the time delays from previous studies at geothermal reservoirs. They have detected a significant increase in time delays between 1988 and 1994, which they attribute to widening of the cracks or filling of the cracks with fluid. Increase in production activities during this time also could have influenced this widening.
Date: September 15, 1999
Creator: Erten, D. & Rial, J. A.
Object Type: Report
System: The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 104, No. 74, Ed. 1 Wednesday, September 15, 1999 (open access)

The Clifton Record (Clifton, Tex.), Vol. 104, No. 74, Ed. 1 Wednesday, September 15, 1999

Semi-weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: September 15, 1999
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History
The Collegian (Hurst, Tex.), Vol. 12, No. 4, Ed. 1 Wednesday, September 15, 1999 (open access)

The Collegian (Hurst, Tex.), Vol. 12, No. 4, Ed. 1 Wednesday, September 15, 1999

Weekly student newspaper published in Hurst, Texas and serving the Tarrant County College District that includes school news and information along with advertising.
Date: September 15, 1999
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Comparison of the Bioavailability of Waste Laden Soils Using ''In Vivo'' ''In Vitro'' Analytical Methodology and Bioaccessibility of Radionuclides for Refinement of Exposure/Dose Estimates (open access)

Comparison of the Bioavailability of Waste Laden Soils Using ''In Vivo'' ''In Vitro'' Analytical Methodology and Bioaccessibility of Radionuclides for Refinement of Exposure/Dose Estimates

The bioavailability of soil contaminants can be measured using in vitro or in vivo techniques. Since there was no standard method for intercomparison among laboratories, we compared two techniques for bioavailability estimation: in vitro dissolution and in vivo rat feeding model for a NIST-traceable soil material. Bioaccessibility was measured using a sequential soil extraction in synthetic analogues of human saliva, gastric and intestinal fluids. Bioavailability was measured in Sprague Dawley rats by determining metal levels in the major organs and urine, feces, and blood. Bioaccessibility was found to be a good indicator of relative metal bioavailability. Results are presented from bioaccessible experiments with Cesium in contaminated DOE soils, and total alpha and beta bioaccessibility. The results indicate that the modified methodology for bioaccessibility can be used for specific radionuclide analysis.
Date: September 15, 1999
Creator: Lioy, P. J.; Gallo, M.; Georgopoulos, P.; Tate, R. & Buckley, B.
Object Type: Report
System: The UNT Digital Library
Comparison of the crevice corrosion resistance of alloys 625 and 22 (open access)

Comparison of the crevice corrosion resistance of alloys 625 and 22

The Yucca Mountain Site Characterization Project is concerned with the corrosion resistance of candidate engineered waste package materials. A variety of waste package designs have been proposed for US and Canadian High Level Nuclear Waste Repositories. A common feature of each design is the possibility of utilizing a corrosion resistant material such as a nickel-based super alloy or titanium-based alloy. A suitable corrosion resistant material may provide (a) kinetic immunity if the combination of repository environmental conditions and alloy resistance assure both: (i) a passive condition with negligible chance of localized corrosion stabilization, as well as (ii) low enough passive dissolution rates to insure conventional corrosion allowance over geological times, (b) a second form of ''corrosion allowance,'' if it can be scientifically demonstrated that a mechanism for stifling (i.e., death) of localized corrosion propagation occurs well before waste canisters are penetrated, or (c) such a low probability of initiation and continued propagation that a tolerably low degree of penetration occurs. Unfortunately, a large database on the crevice corrosion properties of alloy 22 does not exist in comparison to alloy 625. Alloy screening tests in oxidizing acids containing FeCl3 indicate that alloy 22 is more resistant to crevice corrosion than 625 …
Date: September 15, 1999
Creator: Palmer, J.; Kehler, B.; Iloybare, G. O. & Scully, J. R.
Object Type: Article
System: The UNT Digital Library
[District of Columbia Courts/Criminal Justice Act] (open access)

[District of Columbia Courts/Criminal Justice Act]

Other written product issued by the General Accounting Office with an abstract that begins "GAO provided comments on whether the District of Columbia would violate the Antideficiency Act by: (1) approving vouchers for attorney's Criminal Justice Act (CJA) claims after the available fiscal year 1999 appropriations funds were exhausted; and (2) paying out CJA obligations exceeding the limitation contained in the 1999 District of Columbia Appropriations Act, GAO held that: (1) the Courts could not, upon submission of a CJA claim, delay the recognition of an obligation by withholding the voucher's approval; and (2) because attorney representation in CJA cases is a mandatory expense, obligations for this purpose may be incurred and may exceed the capped amount without violating the Antideficiency Act."
Date: September 15, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Electronic transport in extended systems: Application to carbon nanotubes (open access)

Electronic transport in extended systems: Application to carbon nanotubes

Article on electronic transport in extended systems and the application to carbon nanotubes.
Date: September 15, 1999
Creator: Buongiorno Nardelli, Marco
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, September 15, 1999 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, September 15, 1999

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: September 15, 1999
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Federal Reserve Banks: Areas for Improvement in Computer Controls (open access)

Federal Reserve Banks: Areas for Improvement in Computer Controls

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO: (1) followed-up on the status of the Federal Reserve Banks' (FRB) corrective actions to address vulnerabilities identified in GAO's fiscal year (FY) 1997 financial statement audit; and (2) reviewed the general and application controls that support key Financial Management Service (FMS) and Bureau of the Public Debt (BPD) automated financial systems maintained and operated by the FRBs."
Date: September 15, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
The Gayly Oklahoman (Oklahoma City, Okla.), Vol. 17, No. 18, Ed. 1 Wednesday, September 15, 1999 (open access)

The Gayly Oklahoman (Oklahoma City, Okla.), Vol. 17, No. 18, Ed. 1 Wednesday, September 15, 1999

Semi-monthly newspaper from Oklahoma City, Oklahoma that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: September 15, 1999
Creator: Hawkins, Don
Object Type: Newspaper
System: The UNT Digital Library
HLW Canister and Can-In-Canister Drop Calculation (open access)

HLW Canister and Can-In-Canister Drop Calculation

The purpose of this calculation is to evaluate the structural response of the standard high-level waste (HLW) canister and the HLW canister containing the cans of immobilized plutonium (''can-in-canister'' throughout this document) to the drop event during the handling operation. The objective of the calculation is to provide the structure parameter information to support the canister design and the waste handling facility design. Finite element solution is performed using the commercially available ANSYS Version (V) 5.4 finite element code. Two-dimensional (2-D) axisymmetric and three-dimensional (3-D) finite element representations for the standard HLW canister and the can-in-canister are developed and analyzed using the dynamic solver.
Date: September 15, 1999
Creator: Marr, H.
Object Type: Report
System: The UNT Digital Library
Illustrated Paperboy (Cleveland, Tex.), Vol. 7, No. 25, Ed. 1 Wednesday, September 15, 1999 (open access)

Illustrated Paperboy (Cleveland, Tex.), Vol. 7, No. 25, Ed. 1 Wednesday, September 15, 1999

Weekly newspaper from Cleveland, Texas that includes local, county, and state news along with extensive advertising.
Date: September 15, 1999
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Immigration Fundamentals (open access)

Immigration Fundamentals

None
Date: September 15, 1999
Creator: Vialet, Joyce
Object Type: Report
System: The UNT Digital Library
Immigration Fundamentals (open access)

Immigration Fundamentals

Report explaining the fundamentals of immigration in the United States including key terms, statistics, limits, and more.
Date: September 15, 1999
Creator: Vialet, Joyce
Object Type: Report
System: The UNT Digital Library
Improved Estimates of Fault Dose Exterior to the PHENIX South Side Shield Configuration (open access)

Improved Estimates of Fault Dose Exterior to the PHENIX South Side Shield Configuration

None
Date: September 15, 1999
Creator: Stevens, A. J.
Object Type: Report
System: The UNT Digital Library
Increased Mercury Bioaccumulation Follows Water Quality Improvement (open access)

Increased Mercury Bioaccumulation Follows Water Quality Improvement

Changes in physical and chemical characteristics of aquatic habitats made to reduce or eliminate ecological risks can sometimes have unforeseen consequences. Environmental management activities on the U.S. Dept. of Energy reservation in Oak Ridge, Tennessee,have succeeded in improving water quality in streams impacted by discharges fi-om industrial facilities and waste disposal sites. The diversity and abundance of pollution-sensitive components of the benthic macroinvertebrate communities of three streams improved after new waste treatment systems or remedial actions reduced inputs of various toxic chemicals. Two of the streams were known to be mercury-contaminated from historical spills and waste disposal practices. Waterborne mercury concentrations in the third were typical of uncontaminated systems. In each case, concentrations of mercury in fish, or the apparent biological availability of mercury increased over the period during which ecological metrics indicated improved water quality. In the system where waterborne mercury concentrations were at background levels, increased mercury bioaccumulation was probably a result of reduced aqueous selenium concentrations; however, the mechanisms for increased mercury accumulation in the other two streams remain under investigation. In each of the three systems, reduced inputs of metals and inorganic anions was followed by improvements in the health of aquatic invertebrate communities. However, this …
Date: September 15, 1999
Creator: Bogle, M. A.; Peterson, M. J.; Smith, J. G. & Southworth, G. R.
Object Type: Article
System: The UNT Digital Library
Indian Self-Determination Contracting: Shortfalls in Contract Support Costs and Alternatives for Funding Them (open access)

Indian Self-Determination Contracting: Shortfalls in Contract Support Costs and Alternatives for Funding Them

Testimony issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO discussed issues surrounding Indian contract support costs, focusing on: (1) the different categories of contract support costs; (2) the extent of, and reasons for, increases in contract support costs over the last several years; and (3) four alternatives for funding these costs."
Date: September 15, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Intellectual Property Protection for Noncreative Databases (open access)

Intellectual Property Protection for Noncreative Databases

Copyright law protects works of authorship that exhibit original, creative expression, including creativity in the selection, arrangement, or coordination both of traditional printed and electronic databases. Noncreative databases are not subject to copyright protection, although some protection is available through a combination of contract law, trade secrecy law, and misappropriation doctrines of state law.
Date: September 15, 1999
Creator: Schrader, Dorothy & Jeweler, Robin
Object Type: Report
System: The UNT Digital Library