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Advanced Thermal Barrier Coating System Development. Technical progress report (open access)

Advanced Thermal Barrier Coating System Development. Technical progress report

The objectives of the program are to provide an improved TBC system with increased temperature capability and improved reliability relative to current state of the art TBC systems. The development of such a coating system is essential to the ATS engine meeting its objectives. The base program consists of three phases: Phase I: Program Planning - Complete; Phase II: Development - Complete; and Phase III: Selected Specimen - Bench Test. Work was performed on the Phase II final report and on III of the program during the reporting period.
Date: July 14, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 101, No. 107, Ed. 1 Friday, July 14, 2000 (open access)

Altus Times (Altus, Okla.), Vol. 101, No. 107, Ed. 1 Friday, July 14, 2000

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 78, No. 231, Ed. 1 Friday, July 14, 2000 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 78, No. 231, Ed. 1 Friday, July 14, 2000

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Boehmite Sorbs Perrhenate and Pertechnetate (open access)

Boehmite Sorbs Perrhenate and Pertechnetate

None
Date: July 14, 2000
Creator: Zhang, Pengchu; Krumhansl, James L. & Brady, Patrick v.
Object Type: Article
System: The UNT Digital Library
The Boerne Star (Boerne, Tex.), Vol. 95, No. 56, Ed. 1 Friday, July 14, 2000 (open access)

The Boerne Star (Boerne, Tex.), Vol. 95, No. 56, Ed. 1 Friday, July 14, 2000

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Keasling, Edna & Fierro, Jennifer
Object Type: Newspaper
System: The Portal to Texas History
Brady Standard-Herald and Heart O' Texas News (Brady, Tex.), Ed. 1 Friday, July 14, 2000 (open access)

Brady Standard-Herald and Heart O' Texas News (Brady, Tex.), Ed. 1 Friday, July 14, 2000

Semiweekly newspaper from Brady, Texas that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Stewart, James E.
Object Type: Newspaper
System: The Portal to Texas History
Circuit Model for Gun Driven Spheromaks (open access)

Circuit Model for Gun Driven Spheromaks

In this note we derive circuit equations for sustained spheromaks, in the phase after a spheromak is detached from the gun and sustained in a flux conserver. The impedance of the spheromak during the formation and ''bubble burst'' phase has been discussed by Barnes et. al. We assume here that the spheromak is formed and helicity is being delivered to it from the gun, currents are above the threshold current, and the {lambda}-gradients are outward ({lambda} decreasing inward). We follow an open field line that begins and ends at the gun electrodes, encircling the closed flux surfaces of the spheromak, and apply power and helicity balance equations for this gun-driven system. In addition to these equations one will need to know the initial conditions (currents, stored energies) after the ''bubble burst'' in order to project forward in time.
Date: July 14, 2000
Creator: Thomassen, K I
Object Type: Report
System: The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 105, No. 56, Ed. 1 Friday, July 14, 2000 (open access)

The Clifton Record (Clifton, Tex.), Vol. 105, No. 56, Ed. 1 Friday, July 14, 2000

Semi-weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History
Comparative Plutonium-239 Dose Assessment for Three Desert Sites: Maralinga, Australia; Palomares, Spain; and the Nevada Test Site, USA - Before and After Remedial Action (open access)

Comparative Plutonium-239 Dose Assessment for Three Desert Sites: Maralinga, Australia; Palomares, Spain; and the Nevada Test Site, USA - Before and After Remedial Action

As a result of nuclear weapons testing and accidents, plutonium has been distributed into the environment. The areas close to the sites of these tests and accidental dispersions contain plutonium deposition of such a magnitude that health authorities and responsible officials have mandated that the contaminated areas be protected, generally through isolation or removal of the contaminated areas. In recent years remedial actions have taken place at all these sites. For reasons not entirely clear, the public perceives radiation exposure risk to be much greater than the evidence would suggest [1]. This perception seems to be particularly true for plutonium, which has often been ''demonized'' in various publications as the ''most hazardous substance known to man'' [2]. As the position statement adapted by the Health Physics Society explains, ''Plutonium's demonization is an example of how the public has been misled about radiation's environmental and health threats generally, and in cases like plutonium, how it has developed a warped ''risk perception'' that does not reflect reality'' [3]. As a result of this risk perception and ongoing debate surrounding environmental plutonium contamination, remedial action criteria are difficult to establish. By examining the data available before and after remedial actions taken at the …
Date: July 14, 2000
Creator: Church, B. W.; Shinn, J.; Williams, G. A.; Martin, L. J.; O'Brien, R. S. & Adams, S. R.
Object Type: Article
System: The UNT Digital Library
Dallas Voice (Dallas, Tex.), Vol. 17, No. 11, Ed. 1 Friday, July 14, 2000 (open access)

Dallas Voice (Dallas, Tex.), Vol. 17, No. 11, Ed. 1 Friday, July 14, 2000

Weekly newspaper from Dallas, Texas that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: July 14, 2000
Creator: Vercher, Dennis
Object Type: Newspaper
System: The UNT Digital Library
Development of New Hybrid Organic-Inorganic Materials for Hydrogen Separation Membranes at Sandia National Laboratories (open access)

Development of New Hybrid Organic-Inorganic Materials for Hydrogen Separation Membranes at Sandia National Laboratories

None
Date: July 14, 2000
Creator: LOY,DOUGLAS A.
Object Type: Article
System: The UNT Digital Library
Direct Measurement of the Combined Effects of Lichen, Rainfall, and Temperature On silicate Weathering (open access)

Direct Measurement of the Combined Effects of Lichen, Rainfall, and Temperature On silicate Weathering

A key uncertainty in models of the global carbonate-silicate cycle and long-term climate is the way that silicates weather under different climatologic conditions, and in the presence or absence of organic activity. Digital imaging of basalts in Hawaii resolves the coupling between temperature, rainfall, and weathering in the presence and absence of lichens. Activation energies for abiotic dissolution of plagioclase (23.1{+-} 2.5 kcal/mol) and olivine (21.3 {+-} 2.7 kcal/mol) are similar to those measured in the laboratory, and are roughly double those measured from samples taken underneath lichen. Abiotic weathering rates appear to be proportional to rainfall. Dissolution of plagioclase and olivine underneath lichen is far more sensitive to rainfall.
Date: July 14, 2000
Creator: Brady, Patrick V.; Dorn, Ronald I.; Brazel, Anthony J.; Clark, James; Moore, Richard B. & Glidewell, Tiffany
Object Type: Article
System: The UNT Digital Library
Executive and Independent Agency Publications: Where to Get Official Documents (open access)

Executive and Independent Agency Publications: Where to Get Official Documents

This is a directory of telephone numbers and addresses that congressional offices may use to obtain publications from the Executive Office of the President, the executive departments, and the independent agencies and commissions of the federal government. Electronic sources are included for locating copies of government publications on the Internet. The information for each agency was provided by the agency itself.
Date: July 14, 2000
Creator: Campos, Jesus
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Friday, July 14, 2000 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Friday, July 14, 2000

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Fe Oxidizing Bacteria and the Weathering of Fe Silicate Minerals (open access)

Fe Oxidizing Bacteria and the Weathering of Fe Silicate Minerals

None
Date: July 14, 2000
Creator: Santelli, Cara M.; Welch, Susan A.; Westrich, Henry R. & Banfield, Jillian F.
Object Type: Article
System: The UNT Digital Library
Formation of Chloropyromorphite in a Lead-Contaminated Soil Amended with Hydroxyapatite (open access)

Formation of Chloropyromorphite in a Lead-Contaminated Soil Amended with Hydroxyapatite

To confirm conversion of soil Pb to pyromorphite [Pb{sub 5}(PO{sub 4}){sub 3}Cl], a Pb contaminated soil collected adjacent to a historical smelter was reacted with hydroxyapatite in slurries of soil and hydroxyapatite separated by a dialysis membrane and incubated. A crystalline precipitate formed on the dialysis membrane in the slurry systems was identified as chloropyromorphite. Soluble species measured in the soil slurry indicated that dissolution of solid-phase soil Pb was the rate-limiting step for pyromorphite formation. Additionally samples reacted with hydroxyapatite were incubated at field-capacity moisture content. The sequential chemical extraction used to identify species in the field-moist soil incubation experiment showed that hydroxyapatite treatment reduced the first four fractions of extractable Pb and correspondingly increased the recalcitrant extraction residue fraction by 35% of total Pb at 0 d incubation and by 45% after 240 d incubation. the increase in the extraction residue fraction in the 240 d incubation as compared to the 0 d incubation implies that the reaction occurs in the soil but the increase in the hydroxyapatite amended 0 d incubated soil as compared to the control soil illustrates the chemical extraction procedure caused changes in the extractability. Thus, the chemical extraction procedure cannot easily be utilized …
Date: July 14, 2000
Creator: Ryan, James A.; Zhang, Pengchu; Hesterberg, Dean; Zhou, Weiqing & Sayers, Dale E.
Object Type: Article
System: The UNT Digital Library
Grandview Tribune (Grandview, Tex.), Vol. 105, No. 46, Ed. 1 Friday, July 14, 2000 (open access)

Grandview Tribune (Grandview, Tex.), Vol. 105, No. 46, Ed. 1 Friday, July 14, 2000

Weekly newspaper from Grandview, Texas that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Bosher, Casey & Marten, Donna K.
Object Type: Newspaper
System: The Portal to Texas History
Historical Relationship Between Performance Assessment for Radioactive Waste Disposal and Other Types of Risk Assessment in the United States (open access)

Historical Relationship Between Performance Assessment for Radioactive Waste Disposal and Other Types of Risk Assessment in the United States

This paper describes the evolution of the process for assessing the hazards of a geologic disposal system for radioactive waste and, similarly, nuclear power reactors, and the relationship of this process with other assessments of risk, particularly assessments of hazards from manufactured carcinogenic chemicals during use and disposal. This perspective reviews the common history of scientific concepts for risk assessment developed to the 1950s. Computational tools and techniques developed in the late 1950s and early 1960s to analyze the reliability of nuclear weapon delivery systems were adopted in the early 1970s for probabilistic risk assessment of nuclear power reactors, a technology for which behavior was unknown. In turn, these analyses became an important foundation for performance assessment of nuclear waste disposal in the late 1970s. The evaluation of risk to human health and the environment from chemical hazards is built upon methods for assessing the dose response of radionuclides in the 1950s. Despite a shared background, however, societal events, often in the form of legislation, have affected the development path for risk assessment for human health, producing dissimilarities between these risk assessments and those for nuclear facilities. An important difference is the regulator's interest in accounting for uncertainty and the …
Date: July 14, 2000
Creator: RECHARD,ROBERT P.
Object Type: Article
System: The UNT Digital Library
The Hopkins County Echo (Sulphur Springs, Tex.), Vol. 205, No. 24, Ed. 1 Friday, July 14, 2000 (open access)

The Hopkins County Echo (Sulphur Springs, Tex.), Vol. 205, No. 24, Ed. 1 Friday, July 14, 2000

Weekly newspaper from Sulphur Springs, Texas that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Keys, Scott & Lamb, Bill
Object Type: Newspaper
System: The Portal to Texas History
Hudspeth County Herald and Dell Valley Review (Dell City, Tex.), Vol. 43, No. 45, Ed. 1 Friday, July 14, 2000 (open access)

Hudspeth County Herald and Dell Valley Review (Dell City, Tex.), Vol. 43, No. 45, Ed. 1 Friday, July 14, 2000

Weekly newspaper from Dell City, Texas that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Lynch, Mary Louise
Object Type: Newspaper
System: The Portal to Texas History
Innovation Approaches to Development and Ground Testing of Advanced Bimodal Space Power and Propulsion Systems (open access)

Innovation Approaches to Development and Ground Testing of Advanced Bimodal Space Power and Propulsion Systems

The last major development effort for nuclear power and propulsion systems ended in 1993. Currently, there is not an initiative at either the National Aeronautical and Space Administration (NASA) or the U.S. Department of Energy (DOE) that requires the development of new nuclear power and propulsion systems. Studies continue to show nuclear technology as a strong technical candidate to lead the way toward human exploration of adjacent planets or provide power for deep space missions, particularly a 15,000 lbf bimodal nuclear system with 115 kW power capability. The development of nuclear technology for space applications would require technology development in some areas and a major flight qualification program. The last major ground test facility considered for nuclear propulsion qualification was the U.S. Air Force/DOE Space Nuclear Thermal Propulsion Project. Seven years have passed since that effort, and the questions remain the same, how to qualify nuclear power and propulsion systems for future space flight. It can be reasonably assumed that much of the nuclear testing required to qualify a nuclear system for space application will be performed at DOE facilities as demonstrated by the Nuclear Rocket Engine Reactor Experiment (NERVA) and Space Nuclear Thermal Propulsion (SNTP) programs. The nuclear infrastructure …
Date: July 14, 2000
Creator: Hill, T.; Noble, C.; Martinell, J. (INEEL) & Borowski, S. (NASA Glenn Research Center)
Object Type: Article
System: The UNT Digital Library
An Integrated Inventory Information Management System (open access)

An Integrated Inventory Information Management System

None
Date: July 14, 2000
Creator: Thompson, Grace E.; Andrews, Nicole S.; Deland, Sharon M.; Chambers, William B.; Peterson, Marge & Bray, Olin H.
Object Type: Article
System: The UNT Digital Library
LLNL Middle East and North Africa and Former Soviet Union Research Database (open access)

LLNL Middle East and North Africa and Former Soviet Union Research Database

The Lawrence Livermore National Laboratory (LLNL) Ground-Based Nuclear Explosion Monitoring (GNEM) R and D program has made significant progress populating a comprehensive Seismic Research knowledge Base (SRKB) and deriving calibration parameters for the Middle East and North Africa (ME/NA) and Former Soviet Union (FSU) regions. The LLNL SRKB provides not only a coherent framework in which to store and organize very large volumes of collected seismic waveforms, associated event parameter information, and spatial contextual data, but also provides an efficient data processing/research environment for deriving location and discrimination correction surfaces. The SRKB is a flexible and extensible framework consisting of a relational database (RDB), Geographical Information System (GIS), and associated product/data visualization and data management tools. This SRKB framework is designed to accommodate large volumes of data (over 2 million waveforms from 20,000 events) in diverse formats from many sources in addition to maintaining detailed quality control and metadata. Using the SRKB framework, they are combining travel-time observations, event characterization studies, and regional tectonic models to assemble a library of ground truth information and phenomenology correction surfaces required for support of the ME/NA and FSU regionalization program. Corrections and parameters distilled from the LLNL SRKB provide needed contributions to the …
Date: July 14, 2000
Creator: O'Boyle, J.L.; Ruppert, S.D.; Hauk, T. F.; Dodge, D. & Firpo, M.
Object Type: Article
System: The UNT Digital Library
LLNL's 3-D A Priori Model Constraints and Uncertainties for Improving Seismic Location (open access)

LLNL's 3-D A Priori Model Constraints and Uncertainties for Improving Seismic Location

Accurate seismic event location is key to monitoring the Comprehensive Nuclear-Test-Ban Treaty (CTBT) and is largely dependent on our understanding of the crust and mantle velocity structure. This is particularly challenging in aseismic regions, devoid of calibration data, which leads us to rely on a priori constraints on the velocities. We investigate our ability to improve seismic event location in the Middle East, North Africa, and the Former Soviet Union (ME/NA/FSU) by using a priori three-dimensional (3-D) velocity models in lieu of more commonly used one dimensional (1-D) models. Event locations based on 1-D models are often biased, as they do not account for significant travel-time variations that result from heterogeneous crust and mantle; it follows that 3-D velocity models have the potential to reduce this bias. Here, we develop a composite 3-D model for the ME/NA/FSU regions. This fully 3-D model is an amalgamation of studies ranging from seismic reflection to geophysical analogy. Our a priori model specifies geographic boundaries and velocity structures based on geology, tectonics, and seismicity and information taken from published literature, namely a global sediment thickness map of 1{sup o} resolution (Laske and Masters, 1997), a regionalized crustal model based on geology and tectonics (Sweeney …
Date: July 14, 2000
Creator: Flanagan, M P; Myers, S C; Schultz, C A; Pasyanos, M E & Bhattacharyya, J
Object Type: Article
System: The UNT Digital Library