98 Matching Results

Search Results

Results: 1 - 24 next
open access

Clinch River breeder reactor sodium fire protection system design and development

Description: To assure the protection of the public and plant equipment, improbable accidents were hypothesized to form the basis for the design of safety systems. One such accident is the postulated failure of the Intermediate Heat Transfer System (IHTS) piping within the Steam Generator Building (SGB), resulting in a large-scale sodium fire. This paper discusses the design and development of plant features to reduce the consequences of the accident to acceptable levels. Additional design solutions were ma… more
Date: April 13, 1984
Creator: Foster, K.W.; Boasso, C.J. & Kaushal, N.N.
Partner: UNT Libraries Government Documents Department
open access

Materials evaluation for geothermal applications: turbine materials

Description: A number of candidate turbine materials are being evaluated for their resistance to erosion, corrosion, and stress corrosion cracking (SCC) in geothermal brines. These materials include Fe-, Ni-, Co and Ti-base alloys, coatings and ceramics. Tapered wearblades, simulating the leading edge of a turbine blade, are exposed to the direct impact of a two-phase nozzle exhaust. Bent beam SCC specimens, which are constrained in fixtures attached to the wearblade holders, are also exposed to this exhaus… more
Date: April 13, 1977
Creator: Goldberg, A. & Garrison, R.E.
Partner: UNT Libraries Government Documents Department
open access

Multi-year search for a diffuse flxu of muon neutrinos with AMANDA-II

Description: A search for TeV-PeV muon neutrinos from unresolved sources was performed on AMANDA-II data collected between 2000 and 2003 with an equivalent livetime of 807 days. This diffuse analysis sought to find an extraterrestrial neutrino flux from sources with non-thermal components. The signal is expected to have a harder spectrum than the atmospheric muon and neutrino backgrounds. Since no excess of events was seen in the data over the expected background, an upper limit of E{sup 2}{Phi}{sub 90%C.L.… more
Date: April 13, 2008
Creator: Collaboration, IceCube; Klein, Spencer; Achterberg, A. & Collaboration, IceCube
Partner: UNT Libraries Government Documents Department
open access

The silicon microstrip sensors of the ATLAS semiconductor tracker

Description: This paper describes the AC-coupled, single-sided, p-in-n silicon microstrip sensors used in the Semiconductor Tracker (SCT) of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The sensor requirements, specifications and designs are discussed, together with the qualification and quality assurance procedures adopted for their production. The measured sensor performance is presented, both initially and after irradiation to the fluence anticipated after 10 years of LHC operation. The … more
Date: April 13, 2007
Creator: Collaboration, ATLAS SCT & Spieler, Helmuth G.
Partner: UNT Libraries Government Documents Department
open access

Shielding Calculations for NSLS-II Beamlines.

Description: Brookhaven National Laboratory is in the process of designing a new Electron Synchrotron for scientific research using synchrotron radiation. This facility, called the 'National Synchrotron Light Source II' (NSLS-II), will provide x-ray radiation of ultra-high brightness and exceptional spatial and energy resolution. It will also provide advanced insertion devices, optics, detectors, and robotics, and a suite of scientific instruments designed to maximize the scientific output of the facility. … more
Date: April 13, 2008
Creator: Job,P.K. & Casey, W.R.
Partner: UNT Libraries Government Documents Department
open access

Determination of absolute quantum efficiencies by photoacoustic spectroscopy

Description: A method is described whereby the absolute radiative quantum efficiency of paramagnetic ions in liquids or solids can be determined from photoacoustic measurements. 1 figure.
Date: April 13, 1979
Creator: Rosencwaig, A.; Weber, M. J. & Saroyan, R. A.
Partner: UNT Libraries Government Documents Department
open access

Regionalization of ground motion attenuation in the conterminous United States

Description: Attenuation results from geometric spreading and from absorption. The former is almost independent of crustal geology or physiographic region. The latter depends strongly on crustal geology and the state of the earth's upper mantle. Except for very high-frequency waves, absorption does not affect ground motion at distances less than 25 to 50 km. Thus, in the near-field zone, the attenuation in the eastern United States will be similar to that in the western United States. Most of the difference… more
Date: April 13, 1979
Creator: Chung, D.H. & Bernreuter, D.L.
Partner: UNT Libraries Government Documents Department
open access

Genetic algorithms for DNA sequence assembly

Description: This paper describes a genetic algorithm application to the DNA fragment assembly problems. The genetic algorithm uses a random key representation for representing the orderings of fragments. Two different fitness functions, both based on pairwise overlap strengths between fragments, were tested. The paper concludes that the genetic algorithm is a promising method for fragment assembly problems, achieving usable solutions quickly, but that the current fitness functions are flawed and that other… more
Date: April 13, 1993
Creator: Parsons, R.; Burks, C. (Los Alamos National Lab., NM (United States)) & Forrest, S. (New Mexico Univ., Albuquerque, NM (United States). Dept. of Computer Science)
Partner: UNT Libraries Government Documents Department
open access

Stress control of seismicity patterns observed during hydraulic fracturing experiments at the Fenton Hill hot dry rock geothermal energy site, New Mexico

Description: Seismicity accompanying hydraulic injections into granitic rock is often diffuse rather than falling along a single plane. This diffuse zone of seismicity cannot be attributed to systematic errors in locations of the events. It has often been asserted that seismicity occurs along preexisting joints in the rock that are favorably aligned with the stress field so that slip can occur along them when effective stress is reduced by increasing pore fluid pressure. A new scheme for determining orienta… more
Date: April 13, 1987
Creator: Fehler, M. C.
Partner: UNT Libraries Government Documents Department
open access

['At the head of its class' article]

Description: A clipping of an article written by Janet Tyson for the Fort Worth Star-Telegram about Fort Worth school's art programs. It discusses the concerns for a lack of art-related courses in schools and points to Fort Worth as a leader in the initiative to bring them back with the help of NTIEVA and the Getty Center for Education in the Arts.
Date: April 13, 1989
Creator: Tyson, Janet
Partner: UNT Libraries Special Collections
open access

A Filter-Fluorescer Diagnostic System (FFLEX) for the National Ignition Facility (NIF)

Description: An early Filter-Fluorescer Diagnostic System (FFLEX) is being fielded at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) to measure the amount of hard x-rays (20 < hv < 150 keV) generated in laser fusion experiments. From these measurements we hope to quantify the number of hot (20 to 50 keV) electrons produced in laser fusion experiments. The Measurement of hot electron production is important for ignition experiments because these electrons can preh… more
Date: April 13, 2004
Creator: McDonald, J. W.; Kauffman, R. L.; Celeste, J. R.; Rhodes, M. A.; Lee, F. D.; Suter, L. J. et al.
Partner: UNT Libraries Government Documents Department
open access

Preliminary Performance Measurements for a Streak Camera with a Large-Format Direct-Coupled CCD Readout

Description: Livermore's ICF Program has a large inventory of optical streak cameras built in the 1970s and 1980s. The cameras are still very functional, but difficult to maintain because many of their parts are obsolete including the original streak tube and image-intensifier tube. The University of Rochester's Laboratory for Laser Energetics is leading an effort to develop a fully automated, large-format streak camera that incorporates modern technology. Preliminary characterization of a prototype camera … more
Date: April 13, 2004
Creator: Lerche, R. A.; McDonald, J. W.; Griffith, R. L.; de Dios, G. V.; Andrews, D. S.; Huey, A. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Collapsing Bubble in Metal for High Energy Density Physics Study

Description: This paper presents a new idea to produce matter in the high energy density physics (HEDP) regime in the laboratory using an intense ion beam. A gas bubble created inside a solid metal may collapse by driving it with an intense ion beam. The melted metal will compress the gas bubble and supply extra energy to it. Simulations show that the spherical implosion ratio can be about 5 and at the stagnation point, the maximum density, temperature and pressure inside the gas bubble can go up to nearly … more
Date: April 13, 2011
Creator: Ng, S. F.; Barnard, J. J.; Leung, P. T. & Yu, S. S.
Partner: UNT Libraries Government Documents Department
open access

Solar proton fluxes since 1956

Description: The fluxes of protons emitted during solar flares since 1956 were evaluated. The depth-versus-activity profiles of /sup 56/Co in several lunar rocks are consistent with the solar-proton fluxes detected by experiments on several satellites. Only about 20% of the solar-proton-induced activities of /sup 22/Na and /sup 55/Fe in lunar rocks from early Apollo missions were produced by protons emitted from the sun during solar cycle 20 (1965--1975). The depth-versus-activity data for these radionuclid… more
Date: April 13, 1977
Creator: Reedy, R. C.
Partner: UNT Libraries Government Documents Department
open access

Evolution of Static Physical Properties in Plutonium by Self-irradiation Damage

Description: The alpha-decay of plutonium leads to the age-related change in physical properties. This paper presents updated results of age-related effects on enriched and reference alloys measured from immersion density, dilatometry, and mechanical tests. After nearly 100 equivalent years of aging, both the immersion density and dilatometry show that the enriched alloys are decreasing in density by less than 0.02% per year and now exhibit a near linear density decrease, without void swelling. The tensile … more
Date: April 13, 2010
Creator: Chung, B W; Lema, K E & Hiromoto, D S
Partner: UNT Libraries Government Documents Department
open access

An Experimental and Theoretical Multi-Mbar Study of Ti-6Al-4V

Description: We report results from an experimental and theoretical study of the room temperature (RT) compression of the ternary alloy Ti-6Al-4V. In this work, we have extended knowledge of the equation of state (EOS) from 40 GPa to 221 GPa, and observed a different sequence of phase transitions to that reported previously for pure Ti.
Date: April 13, 2011
Creator: Tegner, B. E.; Macleod, S. G.; Cynn, H.; Proctor, J.; Evans, W. J.; McMahon, M. I. et al.
Partner: UNT Libraries Government Documents Department
open access

Opto-electrical characterization and X-ray mapping of large-volume cadmium zinc telluride radiation detectors

Description: Large-volume cadmium zinc telluride (CZT) radiation detectors would greatly improve radiation detection capabilities and, therefore, attract extensive scientific and commercial interests. CZT crystals with volumes as large as hundreds of centimeters can be achieved today due to improvements in the crystal growth technology. However, the poor performance of large-volume CZT detectors is still a challenging problem affecting the commercialization of CZT detectors and imaging arrays. We have emplo… more
Date: April 13, 2009
Creator: Yang, G.; Bolotnikov, A.E.; Camarda, G.S.; Cui, Y.; Hossain, A.; Yao, H.W. et al.
Partner: UNT Libraries Government Documents Department
open access

Genetic algorithms for DNA sequence assembly

Description: This paper describes a genetic algorithm application to the DNA fragment assembly problems. The genetic algorithm uses a random key representation for representing the orderings of fragments. Two different fitness functions, both based on pairwise overlap strengths between fragments, were tested. The paper concludes that the genetic algorithm is a promising method for fragment assembly problems, achieving usable solutions quickly, but that the current fitness functions are flawed and that other… more
Date: April 13, 1993
Creator: Parsons, R.; Burks, C. & Forrest, S.
Partner: UNT Libraries Government Documents Department
open access

Measurements of the Total Charge-Changing Cross Sections for Collisions of Fast Ions with Target Gas Using High Current Experiment

Description: The sum of ionization and charge-exchange cross sections of several gas targets (H2, N2, He, Ne, Kr, Xe, Ar, and water vapor) impacted by 1MeV K+ beam are measured. In a high current ion beam, the self-electric field of the beam is high enough that ions produced from the gas ionization or charge exchange by the ion beam are quickly swept to the sides of accelerator. The flux of the expelled ions is measured by a retarding field analyzer. This allows accurate measuring of the total charge-changi… more
Date: April 13, 2009
Creator: Covo, Michel Kireeff; Molvik, Arthur W.; Kaganovich, Igor D.; Shnidman, Ariel & Vujic, Jasmina L.
Partner: UNT Libraries Government Documents Department
open access

Search for b\to u Transitions in \Bz \to \Dz \Kstarz Decays

Description: We present a study of the decays B{sup 0} {yields} D{sup 0} K*{sup 0} and B{sup 0} {yields} {bar D}{sup 0} K*{sup 0} with K*{sup 0} {yields} K{sup +}{pi}{sup -}. The D{sup 0} and the {bar D}{sup 0} mesons are reconstructed in the final states f = K{sup +} {pi}{sup -}, K{sup +}{pi}{sup -}{pi}{sup 0}, K{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} and their charge conjugates. Using a sample of 465 million B{bar B} pairs collected with the BABAR detector at PEP-II asymmetric-energy e{sup +}e{sup -} col… more
Date: April 13, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Evidence for Nodal Superconductivity in LaFePO from Scanning SQUID Susceptometry

Description: We measure changes in the penetration depth {lambda} of the T{sub c} {approx} 6 K superconductor LaFePO. In the process scanning SQUID susceptometry is demonstrated as a technique for accurately measuring local temperature-dependent changes in {lambda}, making it ideal for studying early or difficult-to-grow materials. {lambda} of LaFePO is found to vary linearly with temperature from 0.36 to {approx} 2 K, with a slope of 143 {+-} 15 {angstrom}/K, suggesting line nodes in the superconducting or… more
Date: April 13, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; /Stanford U., Geballe Lab. /SLAC; Huber, Martin E.; /Colorado U., Denver; Analytis, James G. et al.
Partner: UNT Libraries Government Documents Department
open access

DEVELOPMENT OF ASME SECTION X CODE RULES FOR HIGH PRESSURE COMPOSITE HYDROGEN PRESSURE VESSELS WITH NON-LOAD SHARING LINERS

Description: The Boiler and Pressure Vessel Project Team on Hydrogen Tanks was formed in 2004 to develop Code rules to address the various needs that had been identified for the design and construction of up to 15000 psi hydrogen storage vessel. One of these needs was the development of Code rules for high pressure composite vessels with non-load sharing liners for stationary applications. In 2009, ASME approved new Appendix 8, for Section X Code which contains the rules for these vessels. These vessels are… more
Date: April 13, 2010
Creator: Rawls, G.; Newhouse, N.; Rana, M.; Shelley, B. & Gorman, M.
Partner: UNT Libraries Government Documents Department
open access

A DISCIPLINED APPROACH TO ACCIDENT ANALYSIS DEVELOPMENT AND CONTROL SELECTION

Description: The development and use of a Safety Input Review Committee (SIRC) process promotes consistent and disciplined Accident Analysis (AA) development to ensure that it accurately reflects facility design and operation; and that the credited controls are effective and implementable. Lessons learned from past efforts were reviewed and factored into the development of this new process. The implementation of the SIRC process has eliminated many of the problems previously encountered during Safety Basis … more
Date: April 13, 2007
Creator: Ortner, T & Mukesh Gupta, M
Partner: UNT Libraries Government Documents Department
Back to Top of Screen