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Federal Register, Volume 76, Number 99, May 23, 2011, Pages 29633-29988

Description: Daily publication of the U.S. Office of the Federal Register contains rules and regulations, proposed legislation and rule changes, and other notices, including "Presidential proclamations and Executive Orders, Federal agency documents having general applicability and legal effect, documents required to be published by act of Congress, and other Federal agency documents of public interest" (p. ii). Table of Contents starts on page iii.
Date: May 23, 2011
Creator: United States. Office of the Federal Register.
Partner: UNT Libraries Government Documents Department

EUV/soft x-ray spectra for low B neutron stars

Description: Recent ROSAT and EUVE detections of spin-powered neutron stars suggest that many emit ``thermal`` radiation, peaking in the EUV/soft X-ray band. These data constrain the neutron stars` thermal history, but interpretation requires comparison with model atmosphere computations, since emergent spectra depend strongly on the surface composition and magnetic field. As recent opacity computations show substantial change to absorption cross sections at neutron star photospheric conditions, we report here on new model atmosphere computations employing such data. The results are compared with magnetic atmosphere models and applied to PSR J0437-4715, a low field neutron star.
Date: May 23, 1995
Creator: Romani, R.W.; Rajagopal, M.; Rogers, F.J. & Iglesias, C.A.
Partner: UNT Libraries Government Documents Department

Atomic structure of highly-charged ions. Final report

Description: Atomic properties of multiply charged ions have been investigated using excitation of energetic heavy ion beams. Spectroscopy of excited atomic transitions has been applied from the visible to the extreme ultraviolet wavelength regions to provide accurate atomic structure and transition rate data in selected highly ionized atoms. High-resolution position-sensitive photon detection has been introduced for measurements in the ultraviolet region. The detailed structures of Rydberg states in highly charged beryllium-like ions have been measured as a test of long-range electron-ion interactions. The measurements are supported by multiconfiguration Dirac-Fock calculations and by many-body perturbation theory. The high-angular-momentum Rydberg transitions may be used to establish reference wavelengths and improve the accuracy of ionization energies in highly charged systems. Precision wavelength measurements in highly charged few-electron ions have been performed to test the most accurate relativistic atomic structure calculations for prominent low-lying excited states. Lifetime measurements for allowed and forbidden transitions in highly charged few-electron ions have been made to test theoretical transition matrix elements for simple atomic systems. Precision lifetime measurements in laser-excited alkali atoms have been initiated to establish the accuracy of relativistic atomic many-body theory in many-electron systems.
Date: May 23, 2002
Creator: Livingston, A. Eugene
Partner: UNT Libraries Government Documents Department

Thermal modification of microstructures and grain boundaries in silicon carbide

Description: Polycrystalline SiC samples hot-pressed with aluminum, boron, and carbon sintering additions (ABC-SiC) were characterized using transmission electron microscopy. The study focused on the effects of high temperature treatment on microstructure.
Date: May 23, 2003
Creator: Zhang, Xiao Feng & De Jonghe, Lutgard C.
Partner: UNT Libraries Government Documents Department

Final Report

Description: OAK B135 The formation of metastable crystalline phases in lithium disilicate glass has been a subject of controversy for decades. Here, one aspect of this problem relating to the stability of these non-equilibrium phases when glasses are heated for extended time periods in the nucleation regime is addressed. The results of a systematic experimental investigation on the persistence of metastable phases and the factors that may influence the appearance of such phases, e.g., water content, impurities, glass composition, and glass preparation procedure are presented. Growth rates of lithium disilicate crystals in lithium disilicate glass are measured as a function water concentration in the glass and of temperature in the deeply undercooled regime. The growth rate data obtained in this work are combined with data reported in the literature and used to assess the applicability of standard models of crystal growth for the description of experimental results over a very broad temperature range. The reduced growth rate versus undercooling graph is found to consist of three regimes. For undercoolings less than 140°C, the reduced growth rate curve is suggestive of either 2-D surface nucleation or screw dislocation growth. For undercoolings greater than 400°C, the reduced growth rate plot suggests the operative crystal growth mechanism is 2-D surface nucleation, but detailed calculations cast doubt upon this conclusion. In the intermediate undercooling range, there appears to be some sort of transitional behavior for which none of the standard models appear to be applicable. Further, it is observed that small differences in the viscosity data employed can produce enormous differences in the predicted growth rates at larger undercoolings. Results of the kinetic analyses conducted herein seem to indicate that the nature of the kinetic rate coefficient used in the standard growth models may be incorrect. Nucleation rates of sodium metasilicate crystals in a sodium ...
Date: May 23, 2003
Creator: Weinberg, Michael C.; Burgner, Lori L. & Simmons, Joseph H.
Partner: UNT Libraries Government Documents Department

Tucker Wireline Open Hole Wireline Logging

Description: The Tucker Wireline unit ran a suite of open hole logs right behind the RMOTC logging contractor for comparison purposes. The tools included Dual Laterolog, Phased Induction, BHC Sonic, and Density-Porosity.
Date: May 23, 2002
Creator: Milliken, M.
Partner: UNT Libraries Government Documents Department

PRESENTATION OF SOLUBILITY DATA : UNITS AND APPLICATIONS.

Description: The solubility of gases in water and other aqueous media such as seawater and more concentrated solutions is central to the description of the uptake and reactions of these gases in aerosols, precipitation, surface water and other aqueous media such as the intracellular fluids of plants and animals. It is also pertinent to sampling of soluble atmospheric gases in aqueous medium for analytical purposes. This book presents evaluated summaries of data pertinent to the solubility of gases in aqueous media. This chapter introduces the terminology by which this solubility is described and the pertinent units and presents examples of applications pertinent to atmospheric chemistry. As is seen below, a variety of units have been and continue to be employed for gas solubility data, so some attention must be given to this subject. As this is an IUPAC publication, every effort is made to employ units that are consistent with the International System of Units (Systeme International, SI). However, in IUPAC publications of solubility data it is usual to publish data in the original units in addition to SI units. The consistency of SI makes this system of units convenient for application in atmospheric chemistry and related disciplines. However, as elaborated in the report, there are some departures from strict SI that persist in chemical thermodynamics that require special consideration.
Date: May 23, 2003
Creator: Schwartz, S.
Partner: UNT Libraries Government Documents Department

Characterization and Process Development of Cyanate Ester Resin Composites

Description: Cyanate ester resins offer advantages as composite matrices because of their high thermal stability, low outgassing, low water absorption, and radiation resistance. This paper describes the results of a processing study to develop a high-strength hoop-wound composite by the wet-filament winding method using Toray TI 000G carbon fiber and YLA RS- 14A cyanate ester resin as the constituent materials. The study shows that the cyanate ester resin has a broad process envelope but that an inert-atmosphere cure is essential for obtaining optimum resin and composite properties. Minimizing moisture exposure prior to and during cure is also crucial as it affects the glass transition temperature of the resin and composite. Composite cylinders wound and cured with these methods yielded excellent ring tensile strengths both at room and elevated temperature. A summary of the measured mechanical and thermal property data for these composites is presented. Potential applications for these materials include flywheeI energy storage systems for space and satellite structures.
Date: May 23, 1999
Creator: Frame, B.J.
Partner: UNT Libraries Government Documents Department

FY 1996 solid waste integrated life-cycle forecast characteristics summary. Volumes 1 and 2

Description: For the past six years, a waste volume forecast has been collected annually from onsite and offsite generators that currently ship or are planning to ship solid waste to the Westinghouse Hanford Company`s Central Waste Complex (CWC). This document provides a description of the physical waste forms, hazardous waste constituents, and radionuclides of the waste expected to be shipped to the CWC from 1996 through the remaining life cycle of the Hanford Site (assumed to extend to 2070). In previous years, forecast data has been reported for a 30-year time period; however, the life-cycle approach was adopted this year to maintain consistency with FY 1996 Multi-Year Program Plans. This document is a companion report to two previous reports: the more detailed report on waste volumes, WHC-EP-0900, FY1996 Solid Waste Integrated Life-Cycle Forecast Volume Summary and the report on expected containers, WHC-EP-0903, FY1996 Solid Waste Integrated Life-Cycle Forecast Container Summary. All three documents are based on data gathered during the FY 1995 data call and verified as of January, 1996. These documents are intended to be used in conjunction with other solid waste planning documents as references for short and long-term planning of the WHC Solid Waste Disposal Division`s treatment, storage, and disposal activities over the next several decades. This document focuses on two main characteristics: the physical waste forms and hazardous waste constituents of low-level mixed waste (LLMW) and transuranic waste (both non-mixed and mixed) (TRU(M)). The major generators for each waste category and waste characteristic are also discussed. The characteristics of low-level waste (LLW) are described in Appendix A. In addition, information on radionuclides present in the waste is provided in Appendix B. The FY 1996 forecast data indicate that about 100,900 cubic meters of LLMW and TRU(M) waste is expected to be received at the CWC over the ...
Date: May 23, 1996
Creator: Templeton, K. J.
Partner: UNT Libraries Government Documents Department

X-Ray Scattering Applications Using Pulsed X-Ray Sources

Description: Pulsed x-ray sources have been used in transient structural phenomena investigations for over fifty years; however, until the advent of synchrotrons sources and the development of table-top picosecond lasers, general access to ligh temporal resolution x-ray diffraction was relatively limited. Advances in diffraction techniques, sample excitation schemes, and detector systems, in addition to IncEased access to pulsed sources, have ld tO what is now a diverse and growing array of pulsed-source measurement applications. A survey of time-resolved investigations using pulsed x-ray sources is presented and research opportunities using both present and planned pulsed x-ray sources are discussed.
Date: May 23, 1999
Creator: Larson, B.C.
Partner: UNT Libraries Government Documents Department

A review of ELMs in divertor tokamaks

Description: This paper reviews what is known about edge localized modes (ELMs), with an emphasis on their effect on the scrape-off layer and divertor plasmas. ELM effects have been measured in the ASDEX-U, C-Mod, COMPASS-D, DIII-D, JET, JFT-2M,JT-60U, and TCV tokamaks and are reported here. At least three types of ELMs have been identified and their salient features determined. Type-1 giant ELMs can cause the sudden loss of up to 10-15% of the plasma stored energy but their amplitude ({Delta}W/W) does not increase with increasing power. Type- 3 ELMs are observed near the H-mode power threshold and produce small energy dumps (1-3% of the stored energy). All ELMs increase the scrape- off layer plasma and produce particle fluxes on the divertor targets which are as much as ten times larger that the quiescent phase between ELMs. The divertor heat pulse is largest on the inner target, unlike that of L-Mode or quiescent H-mode; some tokamaks report radial structure in the heat flux profile which is suggestive of islands or helical structures. The power scaling of Type-1 ELM amplitude and frequency have been measured in several tokamaks and has recently been applied to predictions of the ELM Size in ITER. Concern over the expected ELM amplitude has led to a number of experiments aimed at demonstrating active control of ELMs. Impurity gas injection with feedback control on the radiation loss in ASDEX-U suggests that a promising mode of operation (the CDH-mode) with a very small type-3 ELMs can be maintained with heating power sell above the H-mode threshold, where giant type-1 ELMs can be maintained with heating power well above the H-mode threshold, where Giant type-1 ELMs are normally observed. While ELMs have many potential negative effects, the beneficial effect of ELMs in providing density control and limiting the core plasma impurity ...
Date: May 23, 1996
Creator: Hill, D.N.
Partner: UNT Libraries Government Documents Department

Strategy for resolution of the flammable gas safety issue

Description: This document provides a strategy for resolution of the Flammable Gas Safety Issue. It defines the key elements required for the following: Closing the Flammable Gas Unreviewed Safety Question (USQ); Providing the administrative basis for resolving the safety issue; Defining the data needed to support these activities; and Providing the technical and administrative path for removing tanks from the Watch List.
Date: May 23, 1997
Creator: Johnson, G.D.
Partner: UNT Libraries Government Documents Department

Accelerator modeling at SPEAR

Description: The response matrix, consisting of the closed orbit change at each beam position monitor (BPM) due to corrector magnet excitations, was measured and analyzed in order to calibrate a linear optics model of SPEAR. The model calibration was accomplished by varying model parameters to minimize the chi-square difference between the measured and the model response matrices. The singular value decomposition (SVD) matrix inversion method was used to solve the simultaneous equations. The calibrated model was then used to calculate corrections to the operational lattice. The results of the calibration and correction procedures are presented.
Date: May 23, 1997
Creator: LeBlanc, G. & Corbett, W.J.
Partner: UNT Libraries Government Documents Department

Accurate atomistic simulations of the Peierls barrier and kink-pair formation energy for {lt}111{gt} screw dislocations in bcc-Mo

Description: Using multi-ion MGPT interatomic potentials derived from first- principles generalized pseudopotential theory, we have performed accurate atomistic simulations on the energetic of dislocation motion in the bcc transition metal Mo. Our calculated results include the (110) and (211) generalized stacking fault ({gamma}) energy surfaces, the Peierls stress required to move an ideal straight <111> screw dislocation, and the kink-pair formation energy for nonstraight screw dislocations. Many-body angular forces, which are accounted for in the present theory through explicit three- and four-ion potentials, are quantitatively important to such properties for the bcc transition metals. This is demonstrated explicitly through the calculated {gamma} surfaces, which are found to be 10-50% higher in energy than those obtained with pure radial-force models. The Peierls stress for an applied <111>/{l_brace}112{r_brace} shear is computed to be about 0.025{mu}, where {mu} is the bulk shear modulus. For zero applied stress, stable kink pairs are predicted to form for kink lengths greater than 4b, where b is the magnitude of the Burgers vector. For long kinks greater than 15b, the calculated asymptotic value of the kink-pair formation energy is 2.0 eV.
Date: May 23, 1997
Creator: Xu, W. & Moriarty, J.A.
Partner: UNT Libraries Government Documents Department

Advanced ceramics for land-based gas turbine applications. Final report

Description: In order to increase the efficiency of land-based gas turbines, inlet gas temperatures have to be increased, and the amount of air which cools the turbine vanes has to be reduced, to the maximum extent possible. Presently, thermal barrier coatings (TBC`s) are the state of the art in achieving these goals. However, since TBC`s are very thin (typically 100 {mu}m), they have clearly limitations. Since all-ceramic turbine vanes would be a very large and risky development step, Westinghouse is considering to protect the leading edges of turbine vanes with high-performance ceramics. This might be done by either replacing the leading edge with a suitably shaped ceramic part, or by modifying the vanes such that they can accommodate ceramic inserts. Among the most important criteria for the success of ceramics in such applications are (a) thermodynamic compatibility with the turbine vane alloy, (b) sufficient thermal shock resistance to survive the thermal cycling during operation and in particular during emergency shut-down, and a design considering the thermal expansion mismatch of the metallic and ceramic components. This paper presents results of work performed on SiC, SiN, and aluminas.
Date: May 23, 1997
Creator: Schneibel, J.H.; Ludeman, E. & Sabol, S.M.
Partner: UNT Libraries Government Documents Department

Quarterly coal report, October--December 1994

Description: The Quarterly Coal Report (QCR) provides comprehensive information about US coal production, distribution, exports, imports, receipts, prices, consumption, and stocks to a wide audience, including Congress, Federal and State agencies, the coal industry, and the general public. Coke production, consumption, distribution, imports, and exports data are also provided. The data presented in the QCR are collected and published by the Energy Information Administration (EIA) to fulfill data collection and dissemination responsibilities as specified in the Federal Energy Administration Act of 1974 (Public Law 93-275), as amended. This report presents detailed quarterly data for October through December 1994 and aggregated quarterly historical data for 1986 through the third quarter of 1994. Appendix A displays, from 1986 on, detailed quarterly historical coal imports data, as specified in Section 202 of the Energy Policy and Conservation Amendments Act of 1985 (Public Law 99-58). Appendix B gives selected quarterly tables converted to metric tons.
Date: May 23, 1995
Partner: UNT Libraries Government Documents Department

Software quality assurance in the 1996 performance assessment for the Waste Isolation Pilot Plant

Description: The US Department of Energy (DOE) Waste Isolation Pilot Plant (WIPP), located in southeast New Mexico, is a deep geologic repository for the permanent disposal of transuranic waste generated by DOE defense-related activities. Sandia National Laboratories (SNL), in its role as scientific advisor to the DOE, is responsible for evaluating the long-term performance of the WIPP. This risk-based Performance Assessment (PA) is accomplished in part through the use of numerous scientific modeling codes, which rely for some of their inputs on data gathered during characterization of the site. The PA is subject to formal requirements set forth in federal regulations. In particular, the components of the calculation fall under the configuration management and software quality assurance aegis of the American Society of Mechanical Engineers(ASME) Nuclear Quality Assurance (NQA) requirements. This paper describes SNL's implementation of the NQA requirements regarding software quality assurance (SQA). The description of the implementation of SQA for a PA calculation addresses not only the interpretation of the NQA requirements, it also discusses roles, deliverables, and the resources necessary for effective implementation. Finally, examples are given which illustrate the effectiveness of SNL's SQA program, followed by a detailed discussion of lessons learned.
Date: May 23, 2000
Creator: FROEHLICH,GARY K.; OGDEN,HARVEY C. & BYLE,KATHLEEN A.
Partner: UNT Libraries Government Documents Department

Commodity multi-processor systems in the ATLAS level-2 trigger

Description: Low cost SMP (Symmetric Multi-Processor) systems provide substantial CPU and I/O capacity. These features together with the ease of system integration make them an attractive and cost effective solution for a number of real-time applications in event selection. In ATLAS the authors consider them as intelligent input buffers (active ROB complex), as event flow supervisors or as powerful processing nodes. Measurements of the performance of one off-the-shelf commercial 4-processor PC with two PCI buses, equipped with commercial FPGA based data source cards (microEnable) and running commercial software are presented and mapped on such applications together with a long-term program of work. The SMP systems may be considered as an important building block in future data acquisition systems.
Date: May 23, 2000
Creator: Abolins, M.; Blair, R.; Bock, R.; Bogaerts, A.; Dawson, J.; Ermoline, Y. et al.
Partner: UNT Libraries Government Documents Department

GaInNAs laser gain

Description: The optical gain spectra for GaInNAs/GaAs quantum wells are computed using a microscopic laser theory. From these spectra, the peak gain and carrier radiative decay rate as functions of carrier density are determined. These dependences allow the study of the lasing threshold current density of GaInNAs/GaAs quantum well structures.
Date: May 23, 2000
Creator: CHOW,WENG W.; JONES,ERIC D.; MODINE,NORMAND A.; KURTZ,STEVEN R. & ALLERMAN,ANDREW A.
Partner: UNT Libraries Government Documents Department

Neutrons and antimony neutronic evaluations

Description: The new experimental results and recent extensive model development discussed in the companion report ANL/NDM-149 [Smi00], the new resonance parameterization of ref. [Mug99] and experimental results and models available in the literature, are used to construct neutronic evaluations for {sup 121}Sb and {sup 123}Sb in the ENDF/B-6 formats. These are comprehensive evaluations extending from thermal energies to 30 MeV, and include all reactions and processes commonly used in applied neutronic calculations. Comparisons are made with ENDF/B-6 MAT 5125 and 5131 files [ENDF].
Date: May 23, 2000
Creator: Smith, A. B. & Fessler, A.
Partner: UNT Libraries Government Documents Department