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[HIV Health Services Planning Council] (open access)

[HIV Health Services Planning Council]

A reactive publication from the HIV Health Services Planning Council in response to the Ryan White C.A.R.E. Act of 1990.
Date: December 20, 1990
Creator: AIDS Arms Network, Inc.
Object Type: Text
System: The UNT Digital Library
Classification of hydrostratigraphic units at the Savannah River Site, South Carolina (open access)

Classification of hydrostratigraphic units at the Savannah River Site, South Carolina

A detailed synthesis of the hydrologic, geophysical and core data from wells penetrating the updip Mesozoic-Cenozoic Coastal Plain sequence at and near the Savannah River Site (SRS) was conducted to define and classify the hydrostratigraphic units. The purpose of the study was to give the SRS a single unified hydrostratigraphic classification that defines and addresses the hydrogeologic characteristics of the aquifers underlying the site. The characterization, areal distribution and classification of the aquifer and aquifer systems gives SRS the tools to evaluate ground water movement and contaminant transport in a comprehensive regional context. An alpha-numeric nomenclature has been temporarily adopted in this report for classifying the aquifers and aquifer systems at SRS. Formal geographic names for the aquifers and aquifer systems will be proposed in the near future but must be agreed upon and ratified by the South Carolina Hydrostratigraphic Subcommittee which was in part organized for the purpose. The classification utilizes a hierarchy of terms ranked at three levels: Aquifer Systems that transmit ground water regionally; Aquifer Units which are mappable units > 400 square miles in area; and Aquifer Zones that differentiate aquifers internally on the basis of locally significant characteristics.
Date: December 1, 1990
Creator: Aadland, R. K. & Bledsoe, H. W.
Object Type: Report
System: The UNT Digital Library
Classification of hydrostratigraphic units at the Savannah River Site, South Carolina (open access)

Classification of hydrostratigraphic units at the Savannah River Site, South Carolina

A detailed synthesis of the hydrologic, geophysical and core data from wells penetrating the updip Mesozoic-Cenozoic Coastal Plain sequence at and near the Savannah River Site (SRS) was conducted to define and classify the hydrostratigraphic units. The purpose of the study was to give the SRS a single unified hydrostratigraphic classification that defines and addresses the hydrogeologic characteristics of the aquifers underlying the site. The characterization, areal distribution and classification of the aquifer and aquifer systems gives SRS the tools to evaluate ground water movement and contaminant transport in a comprehensive regional context. An alpha-numeric nomenclature has been temporarily adopted in this report for classifying the aquifers and aquifer systems at SRS. Formal geographic names for the aquifers and aquifer systems will be proposed in the near future but must be agreed upon and ratified by the South Carolina Hydrostratigraphic Subcommittee which was in part organized for the purpose. The classification utilizes a hierarchy of terms ranked at three levels: Aquifer Systems that transmit ground water regionally; Aquifer Units which are mappable units > 400 square miles in area; and Aquifer Zones that differentiate aquifers internally on the basis of locally significant characteristics.
Date: December 1, 1990
Creator: Aadland, R. K. & Bledsoe, H. W.
Object Type: Report
System: The UNT Digital Library
First-Time Parenthood: Attachment, Family Variables, Emotional Reactions, and Task Responsibilities as Predictors Of Stress (open access)

First-Time Parenthood: Attachment, Family Variables, Emotional Reactions, and Task Responsibilities as Predictors Of Stress

The purpose of this study was to explore factors which are predictive of parenting stress for first-time parents. Based on attachment theory and empirical research, the factors investigated were the responsibility for child care and housework, the current and retrospective relationship with the family of origin, the change in emotions related to parenthood, the marital relationship, and attachment and individuation.
Date: December 1990
Creator: Abbott, Donna Christine
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Summary of beryllium specifications, current and historical (open access)

Summary of beryllium specifications, current and historical

This report summarizes beryllium properties included in producer, Department of Energy, and government specifications. The specifications are divided into two major categories: current and historical. Within each category the data are arranged primarily according to increasing purity and secondarily by increasing tensile properties. Qualitative comments on formability and weldability are included. Also, short summaries of powder production and consolidation techniques are provided.
Date: December 28, 1990
Creator: Abeln, S.P. & Kyed, P.
Object Type: Report
System: The UNT Digital Library
A novel approach to highly dispersing catalytic materials in coal for gasification. Second quarterly report, January 1, 1990--March 31, 1990 (open access)

A novel approach to highly dispersing catalytic materials in coal for gasification. Second quarterly report, January 1, 1990--March 31, 1990

This project seeks to develop a technique, based on coal surface properties, for highly dispersing catalysts in coal for gasification and to investigate the potential of using potassium carbonate and calcium acetate mixtures as catalysts for coal gasification. The work is focused on the elucidation of coal-catalyst precursor interactions in solution and the variables which control the adsorption and dispersion of coal gasification metal catalysts. In order to optimize coal-metal ion interactions and hence maximize catalyst activity, the study examines the surface electrochemistry of a lignite, a subbituminous, and a bituminous coals and their demineralized and oxidized derivatives prior to loading with the catalytic materials. The surface electrical properties of the coals are investigated with the aid of electrophoresis, while the effects of the surface charge on the adsorption of K{sup +} and Ca{sup 2+} are studied by agitating the coals with aqueous solutions of potassium and calcium. Zeta potential studies show that the surfaces of the lignite are negatively charged between about pH2 to 11, the negative charge density increasing with increase in pH. Highly alkaline media promoted calcium adsorption due to high negative charge on the coal, while calcium uptake was inhibited in strongly acidic solutions.
Date: December 31, 1990
Creator: Abotsi, M. K. & Bota, K. B.
Object Type: Report
System: The UNT Digital Library
Someone to Talk to: Conversations Between Friends in a Junior High Lunch Room (open access)

Someone to Talk to: Conversations Between Friends in a Junior High Lunch Room

Quantitative studies dominate early adolescence research, a field which also lacks an understanding of communication behaviors between early adolescents. This study uses the qualitative methods of participant observation and informal interviews to observe conversations between girls in a junior high lunch room. Friendship characteristics and group socialization are discussed as they emerged from the field data. First, friendship hierarchies (best friend, close friend, and friend) may be adult-imposed structures. Hierarchies are not prominent in the minds of friends as they relate to each other in daily conversation. Second, friendship groups serve to socialize early adolescent girls.
Date: December 1990
Creator: Adams, Brenda Inglis
Object Type: Thesis or Dissertation
System: The UNT Digital Library
2DPUF: A sequential gaussian puff model (open access)

2DPUF: A sequential gaussian puff model

This report documents the Environmental Transport Section`s (ETS) two-dimensional, sequential gaussian puff transport and dispersion model for emergency response. The sequential puff scheme is described, and the dispersion equations are presented. The advantages of this model over the ETS`s PUFF/PLUME model are discussed. Options are calculating a two-dimensional wind field, interpolation procedures, and the wind field grid are described. The various grid systems for puff transport calculations and dose estimates are also described. A flow diagram for the modules comprising the 2DPUF code and a description of each module is presented.
Date: December 31, 1990
Creator: Addis, R. P. & O`Steen, B. L.
Object Type: Report
System: The UNT Digital Library
Removal of trichloroethylene contamination from the subsurface: A comparative evaluation of different remediation strategies by means of numerical simulation (open access)

Removal of trichloroethylene contamination from the subsurface: A comparative evaluation of different remediation strategies by means of numerical simulation

Volatile organic compounds such as petroleum hydrocarbons and halogenated hydrocarbon solvents are common contaminants of the subsurface environment. Although immiscible with water, many of these organics have large enough aqueous phase solubilities to significantly degrade the quality of groundwater with which they come in contact. In addition, many of these substances exhibit high vapor pressures, causing them to partition strongly into the gas phase in their surroundings. Because of these properties, a volatile organic compound (VOC), once introduced into the subsurface may be transported as a solute, a vapor, or as a constituent in a non- aqueous phase liquid (NAPL). This implies that at some sits, an adequate description of the migration of these contaminants in the subsurface would necessarily involve three phases, -- gas, aqueous and NAPL. For example, to design an effective aquifer remediation scheme for a site where NAPL is present, it would be wrong to focus solely on the aqueous phase while ignoring either the gas phase or the NAPL phase. In the present work, we use a simulator developed by Falta et al. (1990a), known as STMVOC,'' which models true three-phase flow in which NAPL, gas and aqueous phases can move in response to pressure, …
Date: December 1, 1990
Creator: Adenekan, A.E.; Pruess, K. & Falta, R.W.
Object Type: Report
System: The UNT Digital Library
Anomalous Behavior in the Rotational Spectra of the v₈=2 and the v₈=3 Vibrations for the ¹³C and ¹⁵N Tagged Isotopes of the CH₃CN Molecule in the Frequency Range 17-95 GHz (open access)

Anomalous Behavior in the Rotational Spectra of the v₈=2 and the v₈=3 Vibrations for the ¹³C and ¹⁵N Tagged Isotopes of the CH₃CN Molecule in the Frequency Range 17-95 GHz

The rotational microwave spectra of the three isotopes (^13CH_3^12C^15N, ^12CH_3^13C^15N, and ^13CH_3^13C^15N) of the methyl cyanide molecule in the v_8=3, v_8=2, v_7=1 and v_4=1 vibrational energy levels for the rotational components 1£J£5 (for a range of frequency 17-95 GHz.) were experimentally and theoretically examined. Rotational components in each vibration were measured to determine the mutual interactions in each vibration between any of the vibrational levels investigated. The method of isotopic substitution was employed for internal tuning of each vibrational level by single and double substitution of ^13C in the two sites of the molecule. It was found that relative frequencies within each vibration with respect to another vibration were shifted in a systematic way. The results given in this work were interpreted on the basis of these energy shifts. Large departure between experimentally measured and theoretically predicted frequency for the quantum sets (J, K=±l, ϑ=±1), Kϑ-l in the v_8=3 vibrational states for the ^13c and ^15N tagged isotopes of CH_3CN showed anomalous behavior which was explained as being due to Fermi resonance. Accidently strong resonances (ASR) were introduced to account for some departures which were not explained by Fermi resonance.
Date: December 1990
Creator: Al-Share, Mohammad A. (Mohammad Abdel)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Hot nuclei -- Landau theory, thermal fluctuations and dissipation (open access)

Hot nuclei -- Landau theory, thermal fluctuations and dissipation

The basic ideas and theoretical methods used in the description of hot nuclei are reviewed. In particular, a macroscopic approach to shape transitions is discussed in the framework of the Landau theory in which the quadrupole shape degrees of freedom play the role of the order parameters. This theory describes the universal features of the nuclear shape evolution with temperature and spin. A unified description of fluctuations in all five quadrupole degrees of freedom is introduced and plays an important role in the calculation of physical observables. A macroscopic approach to the giant dipole resonance (GDR) in hot nuclei is developed. With all parameters fixed by the zero temperature nuclear properties, the theory predicts both the GDR cross-section and angular anisotropy of the {gamma}-rays in very good agreement with recent experiments. The intrinsic shape fluctuations are the main cause for the resonance broadening at higher temperatures, while the orientation fluctuations are responsible for the observed attenuation in the angular anisotropy. Dissipation at finite temperature is discussed in the framework of a Langevin-like equation describing the time-dependent shape fluctuations. Non-adiabatic effects may cause motional narrowing of the resonance.
Date: December 31, 1990
Creator: Alhassid, Y.
Object Type: Article
System: The UNT Digital Library
Uniqueness of Positive Solutions for Elliptic Dirichlet Problems (open access)

Uniqueness of Positive Solutions for Elliptic Dirichlet Problems

In this paper we consider the question of uniqueness of positive solutions for Dirichlet problems of the form - Δ u(x)= g(λ,u(x)) in B, u(x) = 0 on ϑB, where A is the Laplace operator, B is the unit ball in RˆN, and A>0. We show that if g(λ,u)=uˆ(N+2)/(N-2) + λ, that is g has "critical growth", then large positive solutions are unique. We also prove uniqueness of large solutions when g(λ,u)=A f(u) with f(0) < 0, f "superlinear" and monotone. We use a number of methods from nonlinear functional analysis such as variational identities, Sturm comparison theorems and methods of order. We also present a regularity result on linear elliptic equation where a coefficient has critical growth.
Date: December 1990
Creator: Ali, Ismail, 1961-
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Phosphazene polymer containing composites and method for making phosphazene polymer containing composites (open access)

Phosphazene polymer containing composites and method for making phosphazene polymer containing composites

The object of the invention is to provide a composite material comprised of phosphazene polymer. A feature of phosphazene-containing composites is their superior stiffness, thermal stability, and hardness which is lacking in more typical composite constituents. An advantage of using phosphazene composites is a wider range of applications, including uses in harsh environments. Another object of the present invention provides a method for producing phosphazene-containing composite materials through a pultrusion process. In brief, these and other objects are achieved by a composite produced by first coating a reinforcing material with an inorganic phosphazene compound and then polymerizing the phosphazene compound so as to confer superior thermal, physical and chemical resistance qualities to the composite. 2 figs., 6 tabs.
Date: December 31, 1990
Creator: Allen, C. A.; Grey, A. E.; McCaffrey, R. R.; Simpson, B. M. & Stone, M. L.
Object Type: Patent
System: The UNT Digital Library
Establishment of a viable population of red-cockaded woodpeckers at the Savannah River Site. Annual report, FY 1990 (open access)

Establishment of a viable population of red-cockaded woodpeckers at the Savannah River Site. Annual report, FY 1990

In 1985 the Southeastern Forest Experiment Station (SEFES) in cooperation with the Department of Energy, the Savannah River Forest Station (SRFS) and the Savannah River Ecology Laboratory (SREL) initiated a research/management program to restore a viable population of red-cockaded woodpeckers (RCW) to the Savannah River Site (SRS). We managed to stabilize the population in the first couple of years through an intensive flying squirrel removal project as well as augmentation of female RCW`s to the SRS population. We are now in the expansion phase of the project. In 1990 we have focused our efforts on: (1) developing a cavity excavation method and excavating cavities in suitable habitat; (2) flying squirrel control; (3) translocation of RCW`s; (4) monitoring clan composition and reproduction; (5) identification of old-growth stands with the potential of providing new nesting habitat to support population expansion; and (6) surveying lands near SRS where RCW`s were thought to exist. This report summarizes activities for FY 1990 and plans for FY 1991.
Date: December 31, 1990
Creator: Allen, D. H.
Object Type: Report
System: The UNT Digital Library
Trace multielement analysis of reactor moderator water: Simultaneous determination of copper, gold, silver, and mercury using differential pulse stripping voltammetry (open access)

Trace multielement analysis of reactor moderator water: Simultaneous determination of copper, gold, silver, and mercury using differential pulse stripping voltammetry

A rapid, inexpensive trace multi-element analysis of reactor moderator heavy water is described. Samples were analyzed for copper, silver, gold, and mercury at the low ppb level using Differential Pulse Stripping Voltametry (DPSV). These ions are kept below 25 ppb to avoid possible vessel corrosion. A high concentration of aluminum and iron in the samples prevented analysis by ICP spectroscopy. The DPSV method also avoided volatizing highly tritiated samples. Differential Pulse Stripping Voltametry is a commonly used electroanalytical technique for determining trace levels of metals in aqueous solutions. However, application of this method for routine analytical support in a plant laboratory environment was limited due to the method`s sensitivity to interferences. This paper describes a DPSV method which is rugged enough to be used for routine analytical support and addresses method interferences.
Date: December 31, 1990
Creator: Almon, A. C.
Object Type: Article
System: The UNT Digital Library
Electrochemical oxidation of organic waste (open access)

Electrochemical oxidation of organic waste

Both silver catalyzed and direct electrochemical oxidation of organic species are examined in analytical detail. This paper describes the mechanisms, reaction rates, products, intermediates, capabilities, limitations, and optimal reaction conditions of the electrochemical destruction of organic waste. A small bench-top electrocell being tested for the treatment of small quantities of laboratory waste is described. The 200-mL electrochemical cell used has a processing capacity of 50 mL per day, and can treat both radioactive and nonradioactive waste. In the silver catalyzed process, Ag(I) is electrochemically oxidized to Ag(II), which attacks organic species such as tributylphosphate (TBP), tetraphenylborate (TPB), and benzene. In direct electrochemical oxidation, the organic species are destroyed at the surface of the working electrode without the use of silver as an electron transfer agent. This paper focuses on the destruction of tributylphosphate (TBP), although several organic species have been destroyed using this process. The organic species are converted to carbon dioxide, water, and inorganic acids.
Date: December 31, 1990
Creator: Almon, A. C. & Buchanan, B. R.
Object Type: Article
System: The UNT Digital Library
A Search for Massive Compact Halo Objects in Our Galaxy (open access)

A Search for Massive Compact Halo Objects in Our Galaxy

MAssive Compact Halo Objects such as brown dwarfs, Jupiters, and black holes are prime candidates to comprise the dark halo of our galaxy. Paczynski noted that these objects (dubbed MACHOs) can be detected via gravitational microlensing of stars in the Magellanic Clouds with the caveat that only about one in 10{sup 6} stars will be lensed at any given time. Our group is currently involved in constructing a dedicated observing system at the Mount Stromlo Observatory in Australia. We will use a refurbished 1.27 meter telescope and an innovative two-color CCD camera with 3.4 {times} 10{sup 7} pixels to monitor 10{sup 6} {minus} 10{sup 7} stars in the Magellanic Clouds. During the first year of operation (1991--1992), we hope to detect (or rule out) objects in the mass range 0.001M{sub {circle dot}} {le} M {le} 0.1M{sub {circle dot}}, and after five years, we hope to have covered the range 10{sup {minus}6}M{sub {circle dot}} < M {approx lt} 100M{sub {circle dot}}. 4 refs.
Date: December 19, 1990
Creator: Alock, C.; Axelrod, T.; Cook, K.; Park, H. (Lawrence Livermore National Lab., CA (USA)); Griest, K.; Stubbs, C. (California Univ., Berkeley, CA (USA). Center for Particle Astrophysics) et al.
Object Type: Article
System: The UNT Digital Library
Southwest Retort, Volume 44, Number [9], December 1990 (open access)

Southwest Retort, Volume 44, Number [9], December 1990

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: December 1990
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Status and Future Prospects for Supersymmetry at the Tevatron (open access)

Status and Future Prospects for Supersymmetry at the Tevatron

We investigate the potential for discovery of super-symmetry during the next Tevatron Collider run in the light of new results fro LEP and CDF.
Date: December 31, 1990
Creator: Amos, N.; De, K.; White, A. & Yamin, P.
Object Type: Article
System: The UNT Digital Library
Prospects for photosensitive dopants in liquid argon (open access)

Prospects for photosensitive dopants in liquid argon

Evidence is presented that the addition of a few ppM of a photosensitive dopant to a U/liquid argon or Pb/liquid argon calorimeter will make a substantial reduction in the e/{pi} ratio. Previous results indicating high voltage problems and no change in the e/{pi} ratio in tests of photosensitive dopants with the Fermilab D0 experiment's U/liquid argon tests calorimeter are also explained. 13 refs., 3 figs.
Date: December 1, 1990
Creator: Anderson, D.F.
Object Type: Article
System: The UNT Digital Library
ORNL `90 (open access)

ORNL `90

This overview of research conducted at ORNL in 1991 presents information on the subjects of biology, physics, and the environment. Specific topics include gene mutations in kidney disease, technology assessments in thermonuclear fusion, submarine hunting technology, ozone-safe refrigerants, optical data storage via surface enhanced raman spectroscopy, and waste mitigating microbes. (GHH)
Date: December 31, 1990
Creator: Anderson, T.; Barnes, D. & Jefferson, J.
Object Type: Report
System: The UNT Digital Library
CeCu{sub 4}A{ell} and CeCu{sub 2}Zn{sub 2}A{ell}: Very heavy fermion systems in high magnetic fields (open access)

CeCu{sub 4}A{ell} and CeCu{sub 2}Zn{sub 2}A{ell}: Very heavy fermion systems in high magnetic fields

CeCu{sub 4}A{ell} and CeCu{sub 2}Zn{sub 2}A{ell} are heavy fermion systems with extremely enhanced C/T (specific heat divided by temperature) values of 2.3 and 1.8 J/K{sup 2} respectively as T {yields} 0 K. The field dependence of the low temperature specific heat is also extreme; 11 T reduces C of CeCu{sub 4}A{ell} by more than a factor of five, 12.5 T suppresses C of CeCu{sub 2}Zn{sub 2}A{ell} about seven times. Magnetic field caused changes of the specific heat of CeCu{sub 4}A{ell} are consistent with a single ion Kondo model. Magnetic correlations are at least partially responsible for the enhanced low temperature specific heat of CeCu{sub 2}Zn{sub 2}A{ell}.
Date: December 31, 1990
Creator: Andraka, B.; Kim, J. S.; Stewart, G. R. & Fisk, Z.
Object Type: Report
System: The UNT Digital Library
Modeling pCO sub 2 in the upper ocean (open access)

Modeling pCO sub 2 in the upper ocean

This report summarizes our current understanding of the physical, chemical, and biological processes that control the natural cycling of carbon dioxide (CO{sub 2}) in the surface ocean. Because the physics of mixing at the ocean surface creates the essential framework for the chemistry and biology, and because the literature on surface ocean mixing is extensive, a major focus of the report is to review existing mixed layer models for the upper ocean and their implementation in global ocean circulation models. Three families of mixed layer models have been developed. The integrated turbulent kinetic energy'' (TKE) models construct a budget for surface ocean TKE, using the wind stress as source and dissipation as sink for TKE. The shear instability'' models maintain profiles of current velocity resulting from the wind stress. Turbulence closure'' models are the most general and the most complicated of the three types, and are based on laboratory studies of fluid turbulence. This paper explores behavioral distinctions between the three types of models, and summarizes previously published comparisons of the generality, accuracy, and computational requirements of the three models. The application of mixed layer models to treatment of sea ice is also reviewed. 101 refs., 7 figs., 1 tab.
Date: December 1, 1990
Creator: Archer, D.
Object Type: Report
System: The UNT Digital Library
A miniature inexpensive, oxygen sensing element (open access)

A miniature inexpensive, oxygen sensing element

Current progress on the development of the oxygen sensor is reviewed. During this quarter the sensor seal and heating element was redesigned and prototypes were tested. A combustor experiment will be performed in the next one to two quarters. Related information on lean sensors is also reviewed. Additional testing was done on multilayer sensors pulled from storage. (SM)
Date: December 31, 1990
Creator: Arenz, R.W.
Object Type: Report
System: The UNT Digital Library