Search Results

Advanced search parameters have been applied.
open access

What can HELIOS tell us on phase transition of nuclear matter

Description: Transverse energy (E/sub t/) distributions and P/sub t/ spectra of negative particles and photons measured by the HELIOS experiment in 200 GeVN and 60 GeVN oxygen-nucleus reactions are presented. The E/sub t/ distributions are compared to a geometrical parametrization and a Montereverse arrowCarlo calculation, particle spectra to the proton-nucleus reaction case. The comparisons show that yet the results can be understood without assuming quark-gluon plasma formation. A discussion is made based… more
Date: January 1, 1987
Creator: En'yo, H.
Partner: UNT Libraries Government Documents Department
open access

Price 1/sup 0/ x 2/sup 0/ NTMS area, Utah. Data report (abbreviated)

Description: Surface sediment samples were collected at 1444 sites, at a target sampling density of one site per 13 square kilometers. Ground water samples were collected at 137 sites. Neutron activation analysis results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water. Mass spectrometry results are given for helium in ground water. Field measurements and observations are reported for each site. Analytical data and field measurements are presente… more
Date: July 1, 1980
Creator: Cook, J. R.
Partner: UNT Libraries Government Documents Department
open access

Direct spectroscopic observation of charge-exchange recombination of medium-Z elements in the PLT tokamak

Description: We report the first observation of line emission resulting directly from charge-exchange recombination of medium-Z elements (Al, Sc) injected into a PLT discharge. Transitions due to the radiative cascade immediately following charge-exchange of He-like Al and Sc were observed by a VUV spectrograph and two air monochromators. In two cases, AlXI 3209 A and ScXIX 112.1 A, the observed transition had not previously been experimentally identified. Spatial scans provided information on the profile o… more
Date: March 1, 1984
Creator: Skinner, C. H.; Suckewer, S.; Cohen, S. A.; Schilling, G.; Wilson, R. & Stratton, B.
Partner: UNT Libraries Government Documents Department
open access

Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces

Description: We have measured the cross sections for x-ray photoelectron-induced desorption of hydrogen ions from beryllium, carbon, aluminum, tantalum, and gold surfaces. This report describes the results of the cross-section measurements, and discusses a time-of-flight technique that allows the determination of ionic-desorption cross sections as small as 10/sup -25/ cm/sup 2/ per photoelectron. 19 refs., 7 figs.
Date: September 20, 1985
Creator: Kinney, J. H.; Siekhaus, W. J. & Anderson, R. A.
Partner: UNT Libraries Government Documents Department
open access

Sensitivity of primary knock-on atom spectra and displacement per atom cross sections to different secondary neutron energy and angular distributions and ''in-group'' weighting schemes

Description: The sensitivity of primary knock-on atom (PKA) spectra and displacement per atom (DPA) cross sections to different secondary neutron energy and angular distributions and ''in-group'' weighting schemes is investigated. It is shown that the sensitivity of the PKA spectra and DPA cross sections for the (n,n' unresolved) and (n,2n) reactions in Fe to different angular distributions and the same secondary neutron spectrum is reasonably large (approximately 15%), whereas the … more
Date: January 1, 1978
Creator: Gabriel, T. A. & Bishop, B. L.
Partner: UNT Libraries Government Documents Department
open access

Assessment of the theory and hypotheses of the acidification of watersheds

Description: This report documents and critically assesses the evolution and status of the scientific understanding of the effects of acidic deposition on surface waters. The main conclusion is that the dominant theory of surface-water acidification fails to adequately incorporate many important factors and processes that influence surface water acidity. Some of these factors and processes are not well researched or recognized as being important by most scientists in the aquatic effects research area. 258 r… more
Date: April 1, 1989
Creator: Krug, E.C.
Partner: UNT Libraries Government Documents Department
open access

Fluidized-bed waste-heat recovery system development. Semiannual report, February 1, 1983-July 31, 1983

Description: A major energy loss in industry is the heat content of the flue gases from industrial process heaters. One effective way to utilize this energy, which is applicable to all processes, is to preheat the combustion air from the process heater. Although recuperators are available to preheat this air when the flue gases are clean, recuperators to recover the heat from dirty and corrosive flue gases do not exist. The Fluidized-Bed Waste-Heat Recovery (FBWHR) System is designed to preheat this combust… more
Date: August 1, 1983
Creator: Cole, W. E.; De Saro, R. & Joshi, C.
Partner: UNT Libraries Government Documents Department
open access

The rate dependence of the saturation flow stress of Cu and 1100 Al

Description: The strain-rate dependence of the saturation flow stress of OFHC Cu and 1100 Al from 10{sup {minus}3}s{sup {minus}1} to nearly to 10{sup 12}s{sup {minus}1} is examined. The flow stress above 10{sup 9}s{sup {minus}1} is estimated using Wallace's theory of overdriven shocks in metals. A transition to the power-law behavior {Psi} {approximately} {tau}{sub s}{sup 5} occurs at a strain rate of order 10{sup 5}s{sup {minus}1}. 10 refs., 2 figs.
Date: January 1, 1991
Creator: Preston, D.L.; Tonks, D.L. & Wallace, D.C.
Partner: UNT Libraries Government Documents Department
open access

Radioactivities of Long Duration Exposure Facility (LDEF) materials: Baggage and bonanzas

Description: Radioactivities in materials onboard the returned Long Duration Exposure Facility (LDEF) satellite have been studied by a variety of techniques. Among the most powerful is low-background Ge-semiconductor detector gamma-ray spectrometry, illustrated here by results obtained at the Lawrence Berkeley Laboratory's (LBL) Low Bakground Facilities, in a multi-laboratory collaboration coordinated by Dr. Thomas Parnell's team at the Marshall Spacecraft Center, Huntsville, Alabama.
Date: August 1, 1991
Creator: Smith, A. R. & Hurley, D. L.
Partner: UNT Libraries Government Documents Department
open access

Wells 1/sup 0/ x 2/sup 0/ NTMS area, Nevada. Data report (abbreviated)

Description: Surface sediment samples were collected at 1336 sites, at a target sampling density of one site per 13 square kilometers. Ground water samples were collected at 112 sites. Neutron activation analysis results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water and surface water. Mass spectrometry results are given for helium in ground water. Field measurements and observations are reported for each site. Data from ground water and surfac… more
Date: July 1, 1980
Creator: Cook, J. R.
Partner: UNT Libraries Government Documents Department
open access

Improved tunnel resistance of silvered-polymer mirrors

Description: This report documents the research performed at the Solar Energy Research Institute during fiscal year (FY) 1991 to develop ways to prevent delamination failure (known as tunneling) of silvered-polymer reflector materials. Several promising approaches have been identified and demonstrated that substantially reduce such failures. These approaches include (1) use of Tedlar edge tape rather than the manufacturer-recommended ECP-244 tape, (2) thermal treatment of laminated reflector/substrate const… more
Date: October 1, 1991
Creator: Jorgensen, G.; Schissel, P.; Kennedy, C.; Shinton, Y.; Powell, D. & Siebarth, J.
Partner: UNT Libraries Government Documents Department
open access

Advanced photovoltaic concentrator system low-cost prototype module

Description: This report describes the continued development of an extruded lens and the development of a PV receiver, both of which will be used in the Solar Engineering Applications Corporation (SEA) 10X concentrator. These efforts were pare of a pre-Concentrator Initiative Program. The 10X concentrator consists of an inexpensive, extruded linear Fresnel lens which focuses on one-sun cells which are adhesive-bonded to an anodized aluminum heat sink. Module sides are planned to be molded along with the len… more
Date: September 1, 1991
Creator: Kaminar, N.R.; McEntee, J. & Curchod, D. (Solar Engineering Applications Corp., San Jose, CA (United States))
Partner: UNT Libraries Government Documents Department
open access

A numerical study of Rayleigh-Taylor instability in aluminum and steel plates

Description: The SCRAM code is applied to the study of Rayleigh-Taylor instability in metal plates, and comparisons of these computer results are made with experimental data for 1100-O aluminum, 6061-T6 aluminum and 304 stainless steel. Various models for the pressure, temperature, and strain-rate dependencies of the flow stress are compared in the computer calculations. The coefficients that are required in these models to give good agreement with the experimental results are generally close to values that… more
Date: March 1, 1988
Creator: Daly, B.J.
Partner: UNT Libraries Government Documents Department
open access

Energy use in Japan and the United States

Description: This comparative study was undertaken to explain in part the per capita differential between the two countries. In the introduction, the ratios of energy per capita and energy per dollar of Gross Domestic Product (GDP) are presented. The exchange rates utilized to convert GDP to a common currency are discussed in detail. Brief sections on the energy supply and electric generation situation in Japan are included for background information, followed by the body of the report devoted to the energy… more
Date: August 1, 1977
Creator: Doernberg, A
Partner: UNT Libraries Government Documents Department
open access

Solutions to heavy ion induced avalanche burnout in power devices

Description: Silicon power devices fall into two broad categories, bipolar and field effect. Transistors using both of these technologies are often used in satellite applications for power conversion. The present trend is toward integrating power transistors and control electronics on the same chip. In this case, it is the power portion of the chip that is most susceptible to burnout failures, because of it's high voltage operation. Hence, it is important to understand the operational limitations of power t… more
Date: January 1, 1991
Creator: Wrobel, T. F. & Beutler, D. E.
Partner: UNT Libraries Government Documents Department
open access

Fluidized-Bed Waste-Heat Recovery System development. Semiannual report, 1 August 1981-31 January 1982

Description: The Fluidized-Bed Waste-Heat Recovery (FBWHR) System is designed to preheat this combustion air using the heat available in dirty flue gas streams. In this system, a recirculating medium is heated by the flue gas in a fluidized bed. The hot medium is then removed from the bed and placed in a second fluidized bed where it is fluidized by the combustion air. Through this process, the combustion air is heated. The cooled medium is then returned to the first bed. Initial development of this concept… more
Date: February 1, 1982
Creator: Cole, W. E.; DeSaro, R. & Joshi, C.
Partner: UNT Libraries Government Documents Department
open access

Analytical model for the dynamic resistivity of electrically-exploded conductors

Description: A detailed model for the dynamic resistivity of an exploding conductor presents many difficulties. An electrically-exploded conductor undergoes significant hydrodynamic expansion as it is heated. Resistivity is a function of both the temperature and density of a conductor and realistic models for resistivity over the range of parameter space experienced by an exploding conductor are quite complex. See for example, the model of Lee and More (1984). Calculation of the hydrodynamic expansion of th… more
Date: October 10, 1986
Creator: Lee, R. S.
Partner: UNT Libraries Government Documents Department
open access

An assessment of the effects of radiation on permanent magnet material in the ALS (Advanced Light Source) insertion devices

Description: Electrons that are lost from the beam during normal operation of a synchrotron radiation source and during a beam dump at the end of a run produce both ionizing radiation and neutrons. This radiation has the potential for damaging sensitive materials, in particular those that need to be very close to the beam. The wigglers and undulators for the Advanced Light Source (ALS) at LBL will use magnetic materials such as the very high performance neodymium-iron-boron, which will be as close as 1 cm a… more
Date: August 1, 1989
Creator: Hassenzahl, W. V.; Jenkins, T. M.; Namito, Y.; Nelson, W. R. & Swanson, W. P.
Partner: UNT Libraries Government Documents Department
open access

Study of aluminum corrosion in aluminum solar heat collectors using aqueous glycol solution for heat transfer. Semiannual technical progress report, July 30, 1979-January 31, 1980

Description: The present work is addressed primarily to the study of the effects of glycol aging at elevated temperatures (above 100/sup 0/C). Glycols are known to be susceptible to thermal decomposition producing new product species which may be aggressive to aluminum. In addition, the possible breakdown of corrosion inhibitors due to long term exposure to high temperature are also investigated. Both uninhibited and inhibited ethylene (as well as propylene) glycols have been aged at temperatures up to 190/… more
Date: February 1, 1980
Creator: Wong, D.; Cocks, F.H. & Giner, J.
Partner: UNT Libraries Government Documents Department
open access

Spin forming development

Description: Bendix product applications require the capability of fabricating heavy gage, high strength materials. Five commercial sources have been identified that have the capability of spin forming metal thicknesses greater than 9.5 mm and four equiment manufacturers produce machines with this capability. Twelve assemblies selected as candidates for spin forming applications require spin forming of titanium, 250 maraging steel, 17-4 pH stainless steel, Nitronic 40 steel, 304 L stainless steel, and 6061 … more
Date: May 1, 1982
Creator: Gates, W.G.
Partner: UNT Libraries Government Documents Department
open access

Electroless nickel and ion-plated protective coatings for silvered glass mirrors

Description: A preliminary examination of two methods of protecting second surface silvered glass mirrors from environmental degradation is presented. One method employed silver mirrors overcoated with Al, Ni, 304 stainless steel, Cr, or an Al/Cu alloy prepared by ion-plating. The other method used conventional wet process silver mirrors protected with a thin electroless nickel coating. No attempt was made to optimize the coatings for either method. These experimental mirrors were compared with conventional… more
Date: April 1, 1982
Creator: Lind, M. A.; Chaudiere, D. A.; Dake, L. S. & Stewart, T. L.
Partner: UNT Libraries Government Documents Department
open access

Survey and analysis of materials research and development at selected federal laboratories

Description: This document presents the results of an effort to transfer existing, but relatively unknown, materials R and D from selected federal laboratories to industry. More specifically, recent materials-related work at seven federal laboratories potentially applicable to improving process energy efficiency and overall productiviy in six energy-intensive manufacturing industries was evaluated, catalogued, and distributed to industry representatives to gauge their reaction. Laboratories surveyed include… more
Date: April 1, 1984
Creator: Reed, J.E. & Fink, C.R.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen