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LLNL's Regional Model Calibration and Body-Wave Discrimination Research in the Former Soviet Union using Peaceful Nuclear Explosions (PNEs) (open access)

LLNL's Regional Model Calibration and Body-Wave Discrimination Research in the Former Soviet Union using Peaceful Nuclear Explosions (PNEs)

Long-range seismic profiles from Peaceful Nuclear Explosions (PNE) in the Former Soviet Union (FSU) provide a unique data set to investigate several important issues in regional Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring. The recording station spacing ({approx}15 km) allows for extremely dense sampling of the propagation from the source to {approx} 3300 km. This allows us to analyze the waveforms at local, near- and far-regional and teleseismic distances. These data are used to: (1) study the evolution of regional phases and phase amplitude ratios along the profile; (2) infer one-dimensional velocity structure along the profile; and (3) evaluate the spatial correlation of regional and teleseismic travel times and regional phase amplitude ratios. We analyzed waveform data from four PNE's (m{sub b} = 5.1-5.6) recorded along profile KRATON, which is an east-west trending profile located in northern Sibertil. Short-period regional discriminants, such as P/S amplitude ratios, will be essential for seismic monitoring of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) at small magnitudes (m{sub b} < 4.0). However, P/S amplitude ratios in the short-period band, 0.5-5.0 Hz, show some scatter. This scatter is primarily due to propagation and site effects, which arise from variability in the elastic and anelastic structure of the crustal waveguide. …
Date: July 14, 2000
Creator: Bhattacharyya, J.; Rodgers, A.; Swenson, J.; Schultz, C.; Walter, W.; Mooney, W. et al.
Object Type: Article
System: The UNT Digital Library
Marriage Tax Penalties: Legislative Proposals in the 106th Congress (open access)

Marriage Tax Penalties: Legislative Proposals in the 106th Congress

None
Date: July 14, 2000
Creator: Esenwein, Gregg A.
Object Type: Report
System: The UNT Digital Library
A Mechanistic Investigation of Gelation. The Sol-Gel Polymerization of Bridged Silsesquioxane Monomers (open access)

A Mechanistic Investigation of Gelation. The Sol-Gel Polymerization of Bridged Silsesquioxane Monomers

The study of a homologous series of silsesquioxane monomers has uncovered striking discontinuities in gelation behavior. An investigation of the chemistry during the early stages of the polymerization has provided a molecular basis for these observations. Monomers containing from one to four carbon atoms exhibit a pronounced tendency to undergo inter or intramolecular cyclization. The cyclic intermediates have been characterized by {sup 29}Si NMR, chemical ionization mass spectrometry and isolation from the reaction solution. These carbosiloxanes are local thermodynamic sinks that produce kinetic bottlenecks in the production of high molecular weight silsesquioxanes. The formation of cyclics results in slowing down or in some cases completely shutting down gelation. An additional finding is that the cyclic structures are incorporated intact into the final xerogel. Since cyclization alters the structure of the building block that eventually makes up the xerogel network, it is expected that this will contribute importantly to the bulk properties of the xerogel as well.
Date: July 14, 2000
Creator: SHEA,KENNETH J. & LOY,DOUGLAS A.
Object Type: Article
System: The UNT Digital Library
Military Health Care: Factors Affecting Contractors' Ability to Schedule Appointments (open access)

Military Health Care: Factors Affecting Contractors' Ability to Schedule Appointments

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on TRICARE centralized appointment scheduling, focusing on the: (1) proportion of appointments scheduled by TRICARE contractors for beneficiaries in the four TRICARE regions with centralized systems; and (2) factors that affect the contractors' ability to schedule appointments."
Date: July 14, 2000
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Mixing of Isotactic and Syndiotactic Polypropylenes in the Melt (open access)

Mixing of Isotactic and Syndiotactic Polypropylenes in the Melt

The miscibility of polypropylene (PP) melts in which the chains differ only in stereochemical composition has been investigated by two different procedures. One approach used detailed local information from a Monte Carlo simulation of a single chain, and the other approach takes this information from a rotational isomeric state model devised decades ago, for another purpose. The first approach uses PRISM theory to deduce the intermolecular packing in the polymer blend, while the second approach uses a Monte Carlo simulation of a coarse-grained representation of independent chains, expressed on a high-coordination lattice. Both approaches find a positive energy change upon mixing isotactic PP (iPP) and syndiotactic polypropylene (sPP) chains in the melt. This conclusion is qualitatively consistent with observations published recently by Muelhaupt and coworkers. The size of the energy chain on mixing is smaller in the MC/PRISM approach than in the RIS/MC simulation, with the smaller energy change being in better agreement with the experiment. The RIS/MC simulation finds no demixing for iPP and atactic polypropylene (aPP) in the melt, consistent with several experimental observations in the literature. The demixing of the iPP/sPP blend may arise from attractive interactions in the sPP melt that are disrupted when the sPP …
Date: July 14, 2000
Creator: CLANCY,THOMAS C.; PUTZ,MATHIAS; WEINHOLD,JEFFREY D.; CURRO,JOHN G. & MATTICE,WAYNE L.
Object Type: Article
System: The UNT Digital Library
A New Class of Octahedral Molecular Sieve Materials for the Selective Removal and Sequestration of {sup 90}Sr{sup 2+} (open access)

A New Class of Octahedral Molecular Sieve Materials for the Selective Removal and Sequestration of {sup 90}Sr{sup 2+}

The structure of Na{sub 16}Nb{sub 12.8}Ti{sub 3.2}O{sub 44.8}(OH){sub 3.2} {center_dot} 8H{sub 2}O, a member of a new family of Sandia Octahedral Molecular Sieves (SOMS) having a Nb/Na/M{sup IV} (M= Ti, Zr) oxide framework and exchangeable Na and water in open channels, was determined from Synchrotron X-ray data. The SOMS phases are isostructural with variable M{sup IV}:Nb(1:50--1:4) ratios. The SOMS are extremely selective for sorption of divalent cations, particularly Sr{sup 2+}. The ion-exchanged SOMS undergo direct thermal conversion to a perovskite-type phase, indicating this is a promising new method for removal and sequestration of radioactive Sr-90 from mixed nuclear wastes.
Date: July 14, 2000
Creator: Nyman, May D.; Nenoff, Tina M.; Tripathi, Akhilesh; Parise, John B.; Maxwell, Robert S. & Harrison, William T. A.
Object Type: Article
System: The UNT Digital Library
[News Clip: Tobacco Verdit] captions transcript

[News Clip: Tobacco Verdit]

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: July 14, 2000, 4:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 84, No. 168, Ed. 1 Friday, July 14, 2000 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 84, No. 168, Ed. 1 Friday, July 14, 2000

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: July 14, 2000
Creator: Jennings, Sarah
Object Type: Newspaper
System: The Gateway to Oklahoma History
Organically-Templated Zinc Hydrogen Phosphites: Syntheses, Structures and Properties of {alpha}- and {Beta}-ZnHOP{sub 3}{center_dot}N{sub 4}C{sub 2}H{sub 4} (open access)

Organically-Templated Zinc Hydrogen Phosphites: Syntheses, Structures and Properties of {alpha}- and {Beta}-ZnHOP{sub 3}{center_dot}N{sub 4}C{sub 2}H{sub 4}

The syntheses, crystal structures and some properties of {alpha}- and {beta}-ZnHPO{sub 3}{center_dot}N{sub 4}C{sub 2}H{sub 4} are reported. These two polymorphs are the first organically-templated hydrogen phosphites. They are built up from vertex-sharing HPO{sub 3} pseudo pyramids and ZnO{sub 3}N tetrahedra, where the Zn-N bond represents a direct link between zinc and the neutral 2-cyanoguanidine template. {alpha}-ZnHPO{sub 3}{center_dot}N{sub 4}C{sub 2}H{sub 4} is built up from infinite layers of vertex-sharing ZnO{sub 3}N and HPO{sub 3} groups forming 4-rings and 8-rings. {beta}-ZnHPO{sub 3}{center_dot}N{sub 4}C{sub 2}H{sub 4} has strong one-dimensional character, with the polyhedral building units forming 4-ring ladders. Similarities and differences to related zinc phosphates are discussed. Crystal data: {alpha}-ZnHPO{sub 3}{center_dot}N{sub 4}C{sub 2}H{sub 4}, M{sub r} = 229.44, monoclinic, P2{sub 1}/c, a = 9.7718 (5) {angstrom}, b = 8.2503 (4) {angstrom}, c = 9.2491 (5) {angstrom}, {beta} = 104.146 (1){sup 0}, V = 723.1 (1) {angstrom}{sup 3}, R(F) = 2.33%, wR(F) = 2.52%. {beta}-ZnHPO{sub 3}{center_dot}N{sub 4}C{sub 2}H{sub 4}, M{sub r} = 229.44, monoclinic, C2/c, a = 14.5092 (9) {angstrom}, b = 10.5464 (6) {angstrom}, c = 10.3342 (6) {angstrom}, {beta} = 114.290 (1){sup 0}, V = 1441.4 (3) {angstrom}{sup 3}, R(F) = 3.01%, wR(F) = 3.40%.
Date: July 14, 2000
Creator: HARRISON,WILLIAM T.A.; PHILLIPS,MARK L.F.; STANCHFIELD,JESSE & NENOFF,TINA M.
Object Type: Article
System: The UNT Digital Library
Overview of impurity control and wall conditioning in NSTX (open access)

Overview of impurity control and wall conditioning in NSTX

The National Spherical Torus Experiment (NSTX) started plasma operations i n February 1999. In the first extended period of experiments, NSTX achieved high current, inner wall limited, double null, and single null plasma discharges, initial Coaxial Helicity Injection, and High Harmonic Fast Wave results. As expected, discharge reproducibility and performance were strongly affected by wall conditions. In this paper, the authors describe the internal geometry, and initial plasma discharge, impurity control, wall conditioning, erosion, and deposition results.
Date: July 14, 2000
Creator: Kugel, H. W.; Maingi, R.; Wampler, W.; Barry, R. E.; Bell, M.; Blanchard, W. et al.
Object Type: Report
System: The UNT Digital Library
Perry Daily Journal (Perry, Okla.), Vol. 107, No. 138, Ed. 1 Friday, July 14, 2000 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 107, No. 138, Ed. 1 Friday, July 14, 2000

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
Regional Model Calibration for Improving Seismic Location (open access)

Regional Model Calibration for Improving Seismic Location

Accurate seismic event location is integral to the effective monitoring of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), as well as being a fundamental component of earthquake source characterization. To account for the effects of crustal and mantle structure on seismic travel times, and to improve seismic event location in the Middle East and North Africa (MENA), we are developing a set of radially heterogeneous and azimuthally invariant travel-time models of the crust and upper mantle for each MENA seismic station. We begin by developing an average one-dimensional velocity model that minimizes the P-phase travel-time residuals from regional through teleseismic distance at each station. To do this we (1) generate a suite of 1-D velocity models of the earth, (2) compute travel times through the 1-D models using a tau-p formulation to produce standard travel-time tables, and (3) minimize the root-mean-square (rms) residuals between the P-phase arrivals predicted by each model and a groomed set of ISC P-phase arrival times (Engdahl et al., 1991). Once we have an average one-dimensional velocity model that minimizes the P-phase travel-time residuals for all distances, we repeat steps 1 through 3, systematically perturbing the travel-time model and using a grid search procedure to optimize models within …
Date: July 14, 2000
Creator: Swenson, J. L.; Schultz, C. A. & Myers, S. C.
Object Type: Article
System: The UNT Digital Library
Results of the Independent Radiological Verification Survey of Remediation at Building 14, Former Linde Urnaium Refinery, Tonawanda, New York (LI001V) (open access)

Results of the Independent Radiological Verification Survey of Remediation at Building 14, Former Linde Urnaium Refinery, Tonawanda, New York (LI001V)

None
Date: July 14, 2000
Creator: McKenzie, S. P.
Object Type: Report
System: The UNT Digital Library
Safety Evaluation for Packaging (onsite) T Plant Canyon Items (open access)

Safety Evaluation for Packaging (onsite) T Plant Canyon Items

This safety evaluation for packaging (SEP) evaluates and documents the ability to safely ship mostly unique inventories of miscellaneous T Plant canyon waste items (T-P Items) encountered during the canyon deck clean off campaign. In addition, this SEP addresses contaminated items and material that may be shipped in a strong tight package (STP). The shipments meet the criteria for onsite shipments as specified by Fluor Hanford in HNF-PRO-154, Responsibilities and Procedures for all Hazardous Material Shipments.
Date: July 14, 2000
Creator: O'Brien, J. H.
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 264, Ed. 1 Friday, July 14, 2000 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 264, Ed. 1 Friday, July 14, 2000

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: July 14, 2000
Creator: Quinnelly, Lorrie J.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Soluble, High Molecular Weight Polysilsesquioxanes with Carboxylate Functionalities (open access)

Soluble, High Molecular Weight Polysilsesquioxanes with Carboxylate Functionalities

Trialkoxysilyl-containing monomers of the type (RO){sub 3}Si(CH{sub 2}){sub 3}C(O)OtBu (R = Me, Et) were prepared by hydrosilation of the corresponding vinylic tert-butyl esters CH{sub 3}CHCH{sub 2}C(O)OtBu. Acid- or base-catalyzed polymerization of the monomers leads to very high molecular weight polymers with relatively narrow polydispersities. The polymerization results in complete condensation of the alkoxy groups while the tert-butyl ester functionality remains fully intact. Partial or full deprotection of the tert-butyl group can easily be achieved to yield the corresponding carboxylic acid polymers. The ester and carboxylic acid functionalities of these new materials allow for their potential use in a variety of applications such as scavenging of heavy metals.
Date: July 14, 2000
Creator: Rahimian, Kamyar; Loy, Douglas A. & Wheeler, David R.
Object Type: Article
System: The UNT Digital Library
Solvent Influences on the Molecular Aggregation of Magnesium Aryloxides (open access)

Solvent Influences on the Molecular Aggregation of Magnesium Aryloxides

Magnesium aryloxides were prepared in a variety of solvents through the reaction of dibutyl magnesium with sterically varied aryl alcohols: 2,6-dimethylphenol (H-DMP), 2,6-diisopropylphenol (H-DIP), and 2,4,6-trichlorophenol (H-TCP). Upon using a sufficiently strong Lewis-basic solvent, the monomeric species Mg(DMP){sub 2}(py){sub 3} (1, py = pyridine), Mg(DIP){sub 2}(THF){sub 3}, (2a, THF = tetrahydrofuran) Mg(TCP){sub 2}(THF){sub 3} (3) were isolated. Each of these complexes possesses a five-coordinate magnesium that adopts a trigonal bipyramidal geometry. In the absence of a Lewis base, the reaction with H-DIP yields a soluble trinuclear complex, [Mg(DIP){sub 2}]{sub 3} (2b). The Mg metal centers in 2b adopt a linear arrangement with a four-coordinate central metal while the outer metal centers are reduced to just three-coordinate. Solution spectroscopic methods suggest that while 2b remains intact, the monomeric species (1, 2a, and 3) are involved in equilibria, which facilitate intermolecular ligand transfer.
Date: July 14, 2000
Creator: Zechmann, Cecilia A.; Boyle, Timothy J.; Rodriguez, Mark A. & Kemp, Richard A.
Object Type: Article
System: The UNT Digital Library
The structure and dynamics of amorphous and crystalline phases of ice (open access)

The structure and dynamics of amorphous and crystalline phases of ice

The structures of the high and low-density amorphous phases of ice are studied using several techniques. The diffraction patterns of high and low density amorphous ice are analyzed using reverse Monte Carlo methods and compared with molecular dynamics simulations of these phases. The spectra of crystalline and amorphous phases of ice obtained by Raman and incoherent inelastic neutron scattering are analyzed to yield structural features for comparison with the results of molecular dynamics and Reverse Monte Carlo analysis. The structural details obtained indicate that there are significant differences between the structure of liquid water and the amorphous phases of ice.
Date: July 14, 2000
Creator: Klug, D. D.; Tse, J. S.; Tulk, C. A.; Svensson, E. C.; Swainson, I. & Loong, C.-K.
Object Type: Article
System: The UNT Digital Library
Summary of Model Toxics Control Act (MTCA) Potential Impacts Related to Hanford Cleanup and the Tri-Party Agreement (TPA) (open access)

Summary of Model Toxics Control Act (MTCA) Potential Impacts Related to Hanford Cleanup and the Tri-Party Agreement (TPA)

This white paper provides an initial assessment of the potential impacts of the Model Toxics Control Act (MTCA) regulations (and proposed revisions) on the Hanford site cleanup and addresses concerns that MTCA might impose inappropriate or unachievable clean-up levels and drive clean-up costs higher. The white paper and supporting documentation (Appendices A and B) provide DOE with a concise and up-to-date review of potential MTCA impacts to cost and schedule for the Hanford site activities. MTCA, Chapter 70.105D RCW, is the State of Washington's risk based law governing clean-up of contaminated sites and is implemented by The Washington Department of Ecology (Ecology) under the MTCA Clean-up Regulations, Chapter 173-340 WAC. Hanford cleanup is subject to the MTCA requirements as Applicable, Relevant and Appropriate Requirements (ARARs) for those areas of Hanford being managed under the authority of the Federal Resource Conservation and Recovery Act (RCRA), Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), and the state Dangerous Waste Regulations. MTCA provides Ecology with authority to implement site clean-up actions under both the federal RCRA and CERCLA regulations as well as the state regulations. Most of the Hanford clean-up actions are being implemented under the CERCLA program, however, there is a trend …
Date: July 14, 2000
Creator: IWATATE, D.F.
Object Type: Report
System: The UNT Digital Library
Surfactant Templated Mesoporous Hybrid Thin Films (open access)

Surfactant Templated Mesoporous Hybrid Thin Films

None
Date: July 14, 2000
Creator: Fan, Hongyou; Lu, Yunfeng; Assink, Roger A.; Lopez, Gabriel & Brinker, C. Jeffrey
Object Type: Article
System: The UNT Digital Library
Surplus Federal Property (open access)

Surplus Federal Property

The Federal Property and Administrative Services Act of 1949 created new procurement procedures for federal civilian agencies and established the General Services Administration as a central procurement agent.1 Since that time, this enabling law has evolved through amendments to provide GSA with an integrated system of administrative procedures to carry out its federal procurement and supply activities.
Date: July 14, 2000
Creator: Smith, Stephanie
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 25, Number 28, Pages 6619-6860, July 14, 2000 (open access)

Texas Register, Volume 25, Number 28, Pages 6619-6860, July 14, 2000

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: July 14, 2000
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Top-of-Rail lubricant (open access)

Top-of-Rail lubricant

Analysis of the volatile and semivolatile fractions collected after use of the TOR lubricant indicated that other than contaminants in the collection laboratory, no compounds on the EPA's Target Compound Lists (Tables 2 and 5) were detected in these fractions. The data of these qualitative analyses, given in the various tables in the text, indicate only the relative amounts of the tentatively identified compounds. The authors recommend that quantitative analysis be performed on the volatile and semivolatile fractions to allow confirmation of the tentatively identified compounds and to obtain absolute amounts of the detected compounds. Additionally, the semivolatile fraction should be analyzed by liquid chromatography/mass spectrometry to identify compounds that are not chromatographable under the temperature program used for determination of semivolatile compounds. Introducing the top-of-rail (TOR) lubricant into the wheel/rail interface results in a reduction of almost 60% of lateral friction force over the forces encountered under dry conditions. This reveals good potential for energy savings, as well as wear reduction, for railroad companies. In TOR lubrication, an increase in the angle of attack and axle load results in increased lateral friction and rate of lubricant consumption. The most efficient TOR lubricant quantity to be used in the wheel/rail …
Date: July 14, 2000
Creator: Alzoubi, M. F.; Fenske, G. R.; Erck, R. A. & Boparai, A. S.
Object Type: Report
System: The UNT Digital Library
Totally Integrated Munitions Enterprise ''Affordable Munitions Production for the 21st Century'' (open access)

Totally Integrated Munitions Enterprise ''Affordable Munitions Production for the 21st Century''

The U.S. Army faces several munitions manufacturing issues: downsizing of the organic production base, timely fielding of affordable smart munitions, and munitions replenishment during national emergencies. TIME is addressing these complex issues via the development and demonstration of an integrated enterprise. The enterprise will include the tools, network, and open modular architecture controller to enable accelerated acquisition, shortened concept to volume production, lower life cycle costs, capture of critical manufacturing processes, and communication of process parameters between remote sites to rapidly spin-off production for replenishment by commercial sources. TIME addresses the enterprise as a system, integrating design, engineering, manufacturing, administration, and logistics.
Date: July 14, 2000
Creator: Burleson, R. R.; Poggio, M. E.; Rosenberg, S. J. & McWilliams, T.
Object Type: Report
System: The UNT Digital Library