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Input Substitution in Irrigated Agriculture in the High Plains of Texas, 1970-80 (open access)

Input Substitution in Irrigated Agriculture in the High Plains of Texas, 1970-80

This article discusses input substitution in irrigated agriculture in the high plains of Texas.
Date: July 1988
Creator: Nieswiadomy, Michael L.
System: The UNT Digital Library
Solubility of Anthracene in Binary Solvent Mixtures Containing Dibutyl Ether (open access)

Solubility of Anthracene in Binary Solvent Mixtures Containing Dibutyl Ether

Article on the solubility of anthracene in binary solvent mixtures containing dibutyl ether.
Date: July 1987
Creator: Marthandan, Mary V. & Acree, William E. (William Eugene)
System: The UNT Digital Library
National Science Foundation Grants; Young Scholars Projects for High Ability and High Potential Secondary School Students; Guidelines for Proposal Submission (open access)

National Science Foundation Grants; Young Scholars Projects for High Ability and High Potential Secondary School Students; Guidelines for Proposal Submission

Article in the Federal Register, concerning Young Scholars projects, including project development, project environment, project design, activities, the selection of participants, participant costs, project staff, projects site, eligible organizations, budget, proposal preparation and submission, evaluation and selection of proposals, awards, grant administrations, inquiries, program assessment activities, and SST projects.
Date: July 5, 1987
Creator: unknown
System: The UNT Digital Library
[Partial Issue of The Gifted Child Today, July/August 1988] (open access)

[Partial Issue of The Gifted Child Today, July/August 1988]

Table of contents and an article on the Texas Academy of Mathematics and Science by Annetta Ramsey and Rogers Redding in a volume of The Gifted Child Today, with an emphasis on college programs for gifted youngsters.
Date: July 1988
Creator: Gold, Marvin J.
System: The UNT Digital Library
Polycyclic Aromatic Hydrocarbon Solute Probes. Part 6: Effect of Dissolved Oxygen and Halogenated Solvents on the Emission Spectra of Select Probe Molecules (open access)

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 6: Effect of Dissolved Oxygen and Halogenated Solvents on the Emission Spectra of Select Probe Molecules

Article on polycyclic aromatic hydrocarbon solute probes and the effect of dissolved oxygen and halogenated solvents on the emission spectra of select probe molecules.
Date: July 1, 1989
Creator: Tucker, Sheryl A. (Sheryl Ann); Cretella, Lisa E.; Waris, Riaz; Street, Kenneth W.; Acree, William E. (William Eugene) & Fetzer, John Charles, 1953-
System: The UNT Digital Library
Polycyclic Aromatic Hydrocarbon Solute Probes. Part 4: Effect of Solvent Polarity on the Fluorescence Emission Fine Structures of Select Pyrene and Pentaphene Derivatives (open access)

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 4: Effect of Solvent Polarity on the Fluorescence Emission Fine Structures of Select Pyrene and Pentaphene Derivatives

Article on polycyclic aromatic hydrocarbon solute probes and the effect of solvent polarity on the fluorescence emission fine structures of select pyrene and pentaphene derivatives.
Date: July 1, 1989
Creator: Waris, Riaz; Street, Kenneth W.; Acree, William E. (William Eugene) & Fetzer, John Charles, 1953-
System: The UNT Digital Library
Prototype Engineered Barrier System Field Tests; Progress report (open access)

Prototype Engineered Barrier System Field Tests; Progress report

This paper presents selected preliminary results obtained during the first 54 days of the Prototype Engineered Barrier System Field Tests (PEBSFT) that are being performed in G-Tunnel within the Nevada Test Site. The test described is a precursor to the Engineered Barrier Systems Field Tests (EBSFT). The EBSFT will consist of in situ tests of the geohydrologic and geochemical environment in the near field (within a few meters) of heaters emplaced in welded tuff to simulate the thermal effects of waste packages. The PEBSFTs are being conducted to evaluate the applicability of measurement techniques, numerical models, and procedures for future investigations that will be conducted in the Exploratory Shaft Facilities of the Yucca Mountain Project (YMP). The paper discusses the evolution of hydrothermal behavior during the prototype test, including rock temperatures, changes in rock moisture content, air permeability of fractures, gas pressures, and rock mass gas-phase humidity. 10 refs., 12 figs.
Date: July 26, 1989
Creator: Ramirez, A. L.; Beatty, J.; Buscheck, T. A.; Carlson, R.; Daily, W.; LaTorre, V. R. et al.
System: The UNT Digital Library
The influence of penetrating gamma radiation on the reaction of simulated nuclear waste glass in tuff groundwater (open access)

The influence of penetrating gamma radiation on the reaction of simulated nuclear waste glass in tuff groundwater

Static leaching experiments have been performed to determine the influence of penetrating gamma radiation on the reaction of simulated nuclear waste glass in tuff groundwater at 90{degree}C. Both the leachates and the reacted glass monoliths were analyzed to characterize the reaction. Radiation was seen to acidify the leachates, but the high bicarbonate content of the groundwater prevented the pHs from dropping below 6.4. The glass reaction tended to raise the pH. Glass based on SRL 165 black frit and PNL 76-68 glass compositions were leached. The SRL 165 type glasses were quite durable and unaffected by radiation [NL(B) {approximately}4 g/m{sup 2} after 278 days at all exposure rates]. The PNL 76-68 glasses were much less durable, with the durability decreasing as the exposure rate was increased [NL(B) was about 20 g/m{sup 2} after 278 days at 1 {times} 10{sup 3} R/h for both ATM-1c and ATM-8 glasses]. 8 refs., 5 figs.
Date: July 1989
Creator: Ebert, W. L.; Bates, J. K.; Abrajano, T. A., Jr. & Gerding, T. J.
System: The UNT Digital Library
The EQ3/6 software package for geochemical modeling: Current status (open access)

The EQ3/6 software package for geochemical modeling: Current status

EQ3/6 is a software package for modeling chemical and mineralogic interactions in aqueous geochemical systems. The major components of the package are EQ3NR (a speciation-solubility code), EQ6 (a reaction path code), EQLIB (a supporting library), and a supporting thermodynamic data base. EQ3NR calculates aqueous speciation and saturation indices from analytical data. It can also be used to calculate compositions of buffer solutions for use in laboratory experiments. EQ6 computes reaction path models of both equilibrium step processes and kinetic reaction processes. These models can be computed for closed systems and relatively simple open systems. EQ3/6 is useful in making purely theoretical calculations, in designing, interpreting, and extrapolating laboratory experiments, and in testing and developing submodels and supporting data used in these codes. The thermodynamic data base supports calculations over the range 0-300{degree}C. 60 refs., 2 figs.
Date: July 1, 1988
Creator: Wolery, T. J.; Jackson, K. J.; Bourcier, W. L.; Bruton, C. J.; Viani, B. E.; Knauss, K. G. et al.
System: The UNT Digital Library
Modeling of Zircaloy cladding degradation under repository conditions (open access)

Modeling of Zircaloy cladding degradation under repository conditions

Two potential degradation mechanisms, creep and stress corrosion cracking, of Zircaloy cladding during repository storage of spent nuclear fuel have been investigated. The deformation and fracture map methodology has been used to predict maximum allowable initial storage temperatures to achieve a thousand year life without rupture as a function of spent-fuel history. A stress analysis of fuel rods has been performed. Stresses in the outer zirconium oxide layer and the inner Zircaloy tube have been predicted for typical internal pressurization, oxide layer thickness, volume expansion from formation of the oxide layer and thermal expansion coefficients of the cladding and oxide. Stress relaxation occurring in-reactor has also been taken into account. The calculations indicate that for the anticipated storage conditions investigated, the outer zirconium oxide layer is in a state of compression thus making it unlikely that stress corrosion cracking of the exterior surface will occur. 20 refs., 6 figs., 9 tabs.
Date: July 1, 1989
Creator: Santanam, L.; Raghavan, S.; Chin, B. A. & Shaw, H.
System: The UNT Digital Library
Geology and hydrogeology of the proposed nuclear waste repository at Yucca Mountain, Nevada and the surrounding area (open access)

Geology and hydrogeology of the proposed nuclear waste repository at Yucca Mountain, Nevada and the surrounding area

In late 1987 Congress issued an amendment to the Nuclear Waste Policy Act of 1982 which directed the characterization of Yucca Mountain, Nevada as the only remaining potential site for the Nation`s first underground high-level radioactive waste repository. The evaluation of a potential underground repository is guided and regulated by policy established by the Department of Energy (DOE), Nuclear Regulatory Commission (NRC), Environmental Protection Agency (EPA), Department of Transportation (DOT), and the US Congress. The Yucca Mountain Project is the responsibility of the DOE. The purpose of this field trip is to introduce the present state of geologic and hydrologic knowledge concerning this site. This report describes the field trip. 108 refs., 6 figs., 1 tab.
Date: July 1989
Creator: Mattson, S. R.; Broxton, D. E.; Crowe, B. M.; Buono, A. & Orkild, P. P.
System: The UNT Digital Library
Current status of waste package designs for the Yucca Mountain Project (open access)

Current status of waste package designs for the Yucca Mountain Project

Conceptual designs for waste packages containing spent fuel or high-level waste glass have been developed for use in a repository at Yucca Mountain. The basis for these designs reflects the unique nature of the expected service environment associated with disposal in welded tuff in the unsaturated zone. In addition to a set of reference designs, alternative design concepts are being considered that would contain and isolate the waste radionuclides in a more aggressive service environment. Consideration is also being given to the feasibility of a concept known as ``heat tailoring`` that employs the thermal energy released by the wasteforms to enhance and extend the performance of the containers. 5 refs., 3 figs.
Date: July 1, 1989
Creator: Ballou, L. B.
System: The UNT Digital Library
Reflections on the Constitution (open access)

Reflections on the Constitution

Article written by Barbara Jordan for The Houston Lawyer regarding
Date: July 14, 1987
Creator: Jordan, Barbara, 1936-1996
System: The Portal to Texas History
The search for high level parallelism for the iterative solution of large sparse linear systems (open access)

The search for high level parallelism for the iterative solution of large sparse linear systems

In this paper the author is concerned with the numerical solution, based on iterative methods, of large sparse systems of linear algebraic equations of the type which arise in the numerical solution of elliptic and parabolic partial differential equations by finite difference or finite element methods. He considers linear systems of the form Au = b where A is a given N x N matrix which is large and sparse and where b is a given N x 1 column vector. He will assumes that A is symmetric and positive definite (SPD). He considers iterative algorithms which consist of a basic iterative method, such as the Richardson, Jacobi, SSOR or incomplete Cholesky method, combined with an acceleration procedure such as Chebyshev acceleration or conjugate gradient acceleration. The object of this paper is, however, to examine some high-level methods for achieving parallelism. Such techniques involve only matrix/vector operations and do not involve working with blocks of the matrix, subdividing the region, or using different meshes. It is expected that if effective high-level methods could be developed, they could be combined with block and domain decomposition methods, and related methods, to obtain even greater speedups. It is also expected that by working …
Date: July 1, 1988
Creator: Young, D.M.
System: The UNT Digital Library
Glass Making Technology for High-Level Nuclear Waste (open access)

Glass Making Technology for High-Level Nuclear Waste

This paper addresses specific and unique chemical engineering aspects of the Defense Waste Processing Facility (DWPF) at the Savannah River Plant. This paper also addresses the glass melter and those processes that are directly coupled to it. A somewhat disproportionate emphasis is given to sludge pretreatment, for the sake of completeness in this session. We have attempted to focus on those features of the DWPF that may be of general interest or even useful to the practicing chemical engineer.
Date: July 10, 1986
Creator: Boersma, M. D. & Mahoney, J. L.
System: The UNT Digital Library
The Savannah River Site and the Processing Facility Being Built to Prepare its Radioactive Waste for Permanent Disposal (open access)

The Savannah River Site and the Processing Facility Being Built to Prepare its Radioactive Waste for Permanent Disposal

This presentation provides an appreciation for the tremendous chemical processing challenges met in the development of the Defense Waste Process Facility (DWPF) process. The DWPF is presently under construction and is due for completion in 1989. Before radioactive waste is introduced to the DWPF in late 1989, the remote operation of all equipment and all process steps must be demonstrated.
Date: July 10, 1986
Creator: Knight, J. R.
System: The UNT Digital Library
1987 Gordon Research Conference on Physical Metallurgy. (open access)

1987 Gordon Research Conference on Physical Metallurgy.

None
Date: July 24, 1987
Creator: unknown
System: The UNT Digital Library
Material Selection for Defense Waste Processing Facility (open access)

Material Selection for Defense Waste Processing Facility

Construction has started on a facility to immobilize high-level radioactive waste in borosilicate glass at the Department of Energy's Savannah River Plant. Type 304L stainless steel is generally sufficient for supply tankage and service lines. It is used as the reference material in chemical reprocessing of reactor target and fuel tubes. Type 304L, however, has unacceptable stress corrosion cracking resistance in solutions containing formic acid and chloride. Scouting tests were performed on twelve commercial nickel-based alloys in simulated process solutions containing halides, sulfates, nitrates, mercury and formic acid. Mercuric ions and halides interact in acidic environments to increase pitting and crevice attack. Alloys with combined chromium plus molybdenum contents greater than 30 percent, that also contain greater than 9 percent molybdenum, were most resistant to pitting and crevice corrosion. Based on this testing, Alloy C-276 has been selected as the reference process equipment material, with Inconel 690 and ALLCORR selected for specialty areas.
Date: July 17, 1985
Creator: Bickford, D.F.
System: The UNT Digital Library
Comment on "Thermochemical Investigations of Associated Solutions: Calculation of Solute-Solvent Equilibrium Constants from Solubility Measurements" (open access)

Comment on "Thermochemical Investigations of Associated Solutions: Calculation of Solute-Solvent Equilibrium Constants from Solubility Measurements"

This article provides comments on "Thermochemical Investigations of Associated Solutions: Calculation of Solute-Solvent Equilibrium Constants from Solubility Measurements," published in the Journal of Pharmaceutical Sciences in 1983.
Date: July 1, 1987
Creator: Acree, William E. (William Eugene)
System: The UNT Digital Library
Thermochemical Investigations of Associated Solutions: 5. Calculation of Solute-Solvent Equilibrium Constants from Solubility in Mixtures Containing Two Complexing Solvents (open access)

Thermochemical Investigations of Associated Solutions: 5. Calculation of Solute-Solvent Equilibrium Constants from Solubility in Mixtures Containing Two Complexing Solvents

Article on thermochemical investigations of associated solutions and the calculation of solute-solvent equilibrium constants from solubility in mixtures containing two complexing solvents.
Date: July 1, 1987
Creator: Acree, William E. (William Eugene) & McCargar, James W.
System: The UNT Digital Library
Thermochemical Investigations of Associated Solutions: 4. Calculation of Carbazole-Dibutyl Ether Association Constants from Measured Solubility in Binary Solvent Mixtures (open access)

Thermochemical Investigations of Associated Solutions: 4. Calculation of Carbazole-Dibutyl Ether Association Constants from Measured Solubility in Binary Solvent Mixtures

Article on thermochemical investigations of associated solutions and calculation of carbazole-dibutyl ether association constants from measured solubility in binary solvent mixtures.
Date: July 1, 1987
Creator: McCargar, James W.
System: The UNT Digital Library
FINGERPRINTING INORGANIC ARSENIC AND ORGANOARSENIC COMPOUNDS IN IN SITU OIL SHALE RETORT AND PROCESS VOTERS USING A LIQUID CHROMATOGRAPH COUPLED WITH AN ATOMIC ABSORPTION SPECTROMETER AS A DETECTOR (open access)

FINGERPRINTING INORGANIC ARSENIC AND ORGANOARSENIC COMPOUNDS IN IN SITU OIL SHALE RETORT AND PROCESS VOTERS USING A LIQUID CHROMATOGRAPH COUPLED WITH AN ATOMIC ABSORPTION SPECTROMETER AS A DETECTOR

Inorganic arsenic and organoarsenic compounds were speciated in seven oil shale retort and process waters, including samples from simulated, true and modified in situ processes, using a high performance liquid chromatograph automatically coupled to a graphite furnace atomic absorption detector. The molecular forms of arsenic at ppm levels (({micro}g/mL) in these waters are identified for the first time, and shown to include arsenate, methylarsonic acid and phenylarsonic acid. An arsenic-specific fingerprint chromatogram of each retort or process water studied has significant impliestions regarding those arsenical species found and those marginally detected, such as dimethylarsinic acid and the suspected carcinogen arsenite. The method demonstrated suggests future means for quantifying environmental impacts of bioactive organometal species involved in oil shale retorting technology.
Date: July 1, 1981
Creator: Fish, Richard H.; Brinckman, Frederick E. & Jewett, Kenneth L.
System: The UNT Digital Library
FINITE-TEMPERATURE HFB THEORY (open access)

FINITE-TEMPERATURE HFB THEORY

The finite-temperature Hartree-Fock-Bogoliubov (FTHFB) equations are derived. For the pairing Hamiltonian FTHFB simplifies to finite-temperature BCS (FTBCS), The solution of the FTBCS equations for the degenerate model displays a temperature-dependent pairing "phase transition."
Date: July 1, 1980
Creator: Goodman, Alan L.
System: The UNT Digital Library
OBSERVATION OF THE {eta}{sub c} (2980) PRODUCED IN THE RADIATIVE DECAY OF THE {psi}' (3684) (open access)

OBSERVATION OF THE {eta}{sub c} (2980) PRODUCED IN THE RADIATIVE DECAY OF THE {psi}' (3684)

In a study of {psi}'(3684) radiative decays with the Mark II detector at SPEAR, we observe the decay sequence {psi}' {yields} {gamma}{eta}{sub c}(2980), with the {eta}{sub c}(2980) decaying into several completely reconstructed hadronic modes. We obtain a mass M = 2980 ± 8 MeV / c{sup 2} and a width {Gamma} < 40 MeV / c{sup 2} (90% confidence level), and present estimates of some of the decay branching ratios.
Date: July 1, 1980
Creator: Himel, T. M.; Trilling, G. H.; Abrams, G. S.; Alam, M. S.; Blocker, C. A.; Blondel, A. P. et al.
System: The UNT Digital Library