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Component Leakage Testing in Residential Buildings (open access)

Component Leakage Testing in Residential Buildings

The common approach to leakage area measurements in residential housing through pressurization of an entire structure with a blower door. However, this technique does not provide quantitative measurements of the leakiness of individual building components. By pressurizing individual components, it is possible to determine the distribution of leakage within a structure. The studies described in this paper involved measurement of the leakage areas of fireplaces, bathroom and kitchen exhaust vents, electrical outlets and leakage in the ducts of forced air distribution systems. Component leakage measurements were made in a total of thirty-four houses in Atlanta, Georgia, Reno, Nevada and the San Francisco Bay area. Damperless fireplaces and ductwork were found to be the most significant sources of leakage in the western houses. In the Atlanta houses, where cooling loads dominate, the significant leakage area was in the ductwork of the distribution system for central air conditioning that passes through the unconditioned space in the attic and crawlspace.
Date: July 1, 1982
Creator: Dickerhoff, D. J.; Grimsrud, D. T. & Lipschutz, R. D.
System: The UNT Digital Library
Resource investigation of low- and moderate-temperature geothermal areas in San Bernardino, California (open access)

Resource investigation of low- and moderate-temperature geothermal areas in San Bernardino, California

The California Division of Mines and Geology (CDMG) selected the San Bernardino area for detailed geothermal resource investigation because the area was known to contain promising geothermal resource sites, the area contained a large population center, and the City of San Bernardino had expressed serious interest in developing the area's geothermal resource. Ninety-seven geothermal wells and springs were identified and plotted on a compiled geologic map of the 40-square-mile study area. These wells and springs were concentrated in three distinguishable resource areas: Arrowhead Hot Springs, South San Bernardino, and Harlem Hot Springs--in each of which detailed geophysical, geochemical, and geological surveys were conducted. The Arrowhead Hot Springs geothermal area lies just north of the City of San Bernardino in the San Bernardino Mountains astride a shear zone (offshoot of the San Andreas fault) in pre-Cambrian gneiss and schist. The Harlem Hot Springs geothermal area, on the east side of the City, and the South San Bernardino geothermal area, on the south side, have geothermal reservoirs in Quaternary alluvial material which overlies a moderately deep sedimentary basin bound on the southwest by the San Jacinto fault (a ground water barrier). Geothermometry calculations suggest that the Arrowhead Hot Springs geothermal area, with …
Date: July 1, 1982
Creator: Youngs, Leslie G.
System: The UNT Digital Library
An evaluation of the hydrothermal resources of North Dakota, the final phase (open access)

An evaluation of the hydrothermal resources of North Dakota, the final phase

Data relative to aquifer locations, temperature, and water quality for Pleistocene aquifers has been collected and preliminary interpretations of this data are presented here.
Date: July 1, 1982
Creator: Harris, Kenneth L.; Howell, Francis L. & Wartman, Brad L., Anderson, Sidney B.
System: The UNT Digital Library
Geothermal reconnaissance of a portion of the Escalante Valley, Utah (open access)

Geothermal reconnaissance of a portion of the Escalante Valley, Utah

The exploration techniques employed during the study included: (1) Temperature survey of selected wells and springs; (2) Chemical analysis of fluids from selected wells and springs; and (3) Temperature-depth measurements of selected holes of opportunity.
Date: July 1, 1982
Creator: Klauk, R. H.; Foreman, M. B. & Gourley, C.
System: The UNT Digital Library
Studies of injection into naturally fractured reservoirs (open access)

Studies of injection into naturally fractured reservoirs

A semi-analytical model for studies of cold water injectioninto naturally fractured reservoirs has been developed. The model can beused to design the flow rates and location of injection wells in suchsystems. The results obtained using the model show that initially thecold water will move very rapidly through the fracture system away fromthe well. Later on, conductive heat transfer from the rock matrix blockswill retard the advancement of the cold water front, and eventuallyuniform energy sweep conditions will prevail. Where uniform energy sweepconditions are reached the cold waer movement away from the injectionwell will be identical to that in a porous medium; consequently maximumenergy recovery from the rock matrix will be attained. The time ofuniform energy sweep and the radial distance from the injection wellwhere it occurs are greatly dependent upon the fracture spacing, butindependent of the fracture aperture.
Date: July 1, 1982
Creator: Bodvarsson, Gudmundur S. & Lai, Cheng Hsien
System: The UNT Digital Library
Studies of injection into naturally fractured reservoirs (open access)

Studies of injection into naturally fractured reservoirs

A semi-analytical model for studies of cold water injectioninto naturally fractured reservoirs has been developed. The model can beused to design the flow rates and location of injection wells in suchsystems. The results obtained using the model show that initially thecold water will move very rapidly through the fracture system away fromthe well. Later on, conductive heat transfer from the rock matrix blockswill retard the advancement of the cold water front, and eventuallyuniform energy sweep conditions will prevail. Where uniform energy sweepconditions are reached the cold waer movement away from the injectionwell will be identical to that in a porous medium; consequently maximumenergy recovery from the rock matrix will be attained. The time ofuniform energy sweep and the radial distance from the injection wellwhere it occurs are greatly dependent upon the fracture spacing, butindependent of the fracture aperture.
Date: July 1, 1982
Creator: Bodvarsson, Gudmundur S. & Lai, Cheng Hsien
System: The UNT Digital Library
Future engineering needs of mirror fusion reactors (open access)

Future engineering needs of mirror fusion reactors

Fusion research has matured during the last decade and significant insight into the future program needs has emerged. While some will properly note that the crystal ball is cloudy, it is equally important to note that the shape and outline of our course is discernable. In this short summary paper, I will draw upon the National Mirror Program Plan for mirror projects and on available design studies of these projects to put the specific needs of the mirror program in perspective.
Date: July 30, 1982
Creator: Thomassen, K.I.
System: The UNT Digital Library
Synchrotron x-ray study of physisorbed films of mixtures of Ar and Xe on graphite (open access)

Synchrotron x-ray study of physisorbed films of mixtures of Ar and Xe on graphite

Mixtures of Ar and Xe have been studied in most of the submonolayer region of the phase diagram (T,chi,rho), T = temperature, chi = chemical composition, rho = fraction of a monolayer. The basic feature is a large tendency to form ..sqrt.. 3 x ..sqrt.. 3 commensurate alloys (Kr-like structures), but none of the commensurate nor of the incommensurate structures form a chemically ordered alloy at 11 K. Thus the 2D solid can be thought of as a solid consisting of particles of an average size. This allows the study of commensurate-incommensurate phase transition driven by average particle size. The transition is indeed a sharp first order transition taking place through coexisting phases (tau/sub A/ = 1.64 A/sup -1/ and tau/sub B/ = 1.703 A/sup -1/), as was the case for the low temperature pure Kr-system. Another interesting feature is the existence of well correlated liquid-like structures which preserve their correlation over a temperature range of 5 Kelvin or more. This unusual behavior is for chemical compositions where there is coexistence of a commensurate and an incommensurate solid at high temperature.
Date: July 1, 1982
Creator: Bohr, J.; Nielsen, M.; McTague, J. P.; Als-Nielsen, J. & Kjaer, K.
System: The UNT Digital Library
Lawrence Livermore National Laboratory laser-fusion program (open access)

Lawrence Livermore National Laboratory laser-fusion program

The goals of the Laser-Fusion Program at Lawrence Livermore National Laboratory are to produce well-diagnosed, high-gain, laser-driven fusion explosions in the laboratory and to exploit this capability for both military applications and for civilian energy production. In the past year we have made significant progress both theoretically and experimentally in our understanding of the laser interaction with both directly coupled and radiation-driven implosion targets and their implosion dynamics. We have made significant developments in fabricating the target structures. Data from the target experiments are producing important near-term physics results. We have also continued to develop attractive reactor concepts which illustrate ICF's potential as an energy producer.
Date: July 12, 1982
Creator: Ahlstrom, H.G.
System: The UNT Digital Library
Bubble-chamber experiments on charmed-particle lifetimes (open access)

Bubble-chamber experiments on charmed-particle lifetimes

The three current bubble-chamber experiments on charmed-particle lifetimes are compared. Their most recently released results are discussed.
Date: July 1, 1982
Creator: Field, R.C.
System: The UNT Digital Library
Double-mode pulsation (open access)

Double-mode pulsation

Double mode pulsation is a very pervasive phenomenon in stars all over the Hertzsprung-Russell diagram. In order of increasing radius, examples are: ZZ Ceti stars, the sun, the delta Scuti stars, RR Lyrae variables, the ..beta.. Cephei variables and those related to them, Cepheids, and maybe even the Mira stars. These many modes have been interpreted as both radial and nonradial modes, but in many cases the actual mode has not been clearly identified. Yellow giants seem to be the most simple pulsators with a large majority of the RR Lyrae variables and Cepheids showing only one pulsation period. We limit this review to those very few cases for classical Cepheids and RR Lyrae variables which display two modes. For these we know many facts about these stars, but the actual cause of the pulsation in two modes simultaneously remains unknown.
Date: July 30, 1982
Creator: Cox, A. N.
System: The UNT Digital Library
Collision of fast highly charged ions in gas targets: ionization, recoil-ion production, and charge transfer (open access)

Collision of fast highly charged ions in gas targets: ionization, recoil-ion production, and charge transfer

Electron-capture, ionization, and recoil-ion-production cross sections are measured and calculated for fast highly charged projectiles in hydrogen and rare-gas targets. Recoil-ion-production cross sections are found to be large; the low energy and high charge states of the recoil ions make them useful for subsequent collision studies.
Date: July 1, 1982
Creator: Schalchter, A.S.; Berkner, K.H. & Beyer, H.F.
System: The UNT Digital Library
Formation and characterization of fission-product aerosols under postulated HTGR accident conditions (open access)

Formation and characterization of fission-product aerosols under postulated HTGR accident conditions

The paper presents the results of an experimental investigation on the formation mechanism and physical characterization of simulated nuclear aerosols that could likely be released during an HTGR core heat-up accident. Experiments were carried out in a high-temperature flow system consisting essentially of an inductively heated release source, a vapor deposition tube, and a filter assembly for collecting particulate matter. Simulated fission products Sr and Ba as oxides are separately impregnated in H451 graphite wafers and released at elevated temperatures into a dry helium flow. In the presence of graphite, the oxides are quantitatively reduced to metals, which subsequently vaporize at temperatures much lower than required for the oxides alone to vaporize in the absence of graphite. A substantial fraction of the released material is associated with particulate matter, which is collected on filters located downstream at ambient temperature. The release and transport of simulated fission product Ag as metal are also investigated.
Date: July 1, 1982
Creator: Tang, I.N. & Munkelwitz, H.R.
System: The UNT Digital Library
GUTs, SUSY GUTs and SUPER GUTs (open access)

GUTs, SUSY GUTs and SUPER GUTs

We review the motivations for extending grand unified theories with particular emphasis on supersymmetry and its phenomenological and cosmological fallout, and comment on the relevance of quantum gravity. 67 references.
Date: July 1, 1982
Creator: Gaillard, M. K.
System: The UNT Digital Library
Behavior of nuclei at high angular momentum (open access)

Behavior of nuclei at high angular momentum

The present report begins with a brief overview of nuclear shapes and level structures at high-spin values. The new spectroscopy associated with angular-momentum alignments is described, and some of the exciting possibilities of this spectroscopy are explored. Nuclear moments of inertia are discussed and a somewhat different one is defined, together with a method for measuring it and some early results. Finally a few comments on the future prospects for high-spin physics are offered.
Date: July 1, 1982
Creator: Stephens, F.S.
System: The UNT Digital Library
TMX tandem-mirror experiments and thermal-barrier theoretical studies (open access)

TMX tandem-mirror experiments and thermal-barrier theoretical studies

This paper describes recent analysis of energy confinement in the Tandem Mirror Experiment (TMX). TMX data also indicates that warm plasma limits the amplitude of the anisotropy driven Alfven ion cyclotron (AIC) mode. Theoretical calculations show strong AIC stabilization with off-normal beam injection as planned in TMX-U and MFTF-B. This paper reports results of theoretical analysis of hot electrons in thermal barriers including electron heating calculations by Monte Carlo and Fokker-Planck codes and analysis of hot electron MHD and microinstability. Initial results from the TMX-U experiment are presented which show the presence of sloshing ions.
Date: July 29, 1982
Creator: Simonen, T. C.; Baldwin, D. E. & Allen, S. L.
System: The UNT Digital Library
TMX tandem-mirror experiments and thermal-barrier theoretical studies (open access)

TMX tandem-mirror experiments and thermal-barrier theoretical studies

This paper describes recent analysis of energy confinement in the Tandem Mirror Experiment (TMX). TMX data also indicates that warm plasma limits the amplitude of the anisotropy driven Alfven ion cyclotron (AIC) mode. Theoretical calculations show strong AIC stabilization with off-normal beam injection as planned in TMX-U and MFTF-B. This paper reports results of theoretical analysis of hot electrons in thermal barriers including electron heating calculations by Monte Carlo and Fokker-Planck codes and analysis of hot electron MHD and microinstability. Initial results from the TMX-U experiment are presented which show the presence of sloshing ions.
Date: July 29, 1982
Creator: Simonen, T. C.; Baldwin, D. E. & Allen, S. L.
System: The UNT Digital Library
Theory and simulation of laser plasma coupling-II (open access)

Theory and simulation of laser plasma coupling-II

In previous lectures at the 1979 Scottish Universities' Summer School in Physics, we presented an introduction to the theory and simulation of laser plasma interactions. A representative mix of coupling processes was discussed. In this update lecture for the 1982 school, we will emphasize two specific topics which have received increased attention in the last few years: stimulated Raman scatter and the wavelength scaling of laser plasma coupling.
Date: July 29, 1982
Creator: Kruer, W.L.
System: The UNT Digital Library
Workshop on environmental assessment. [Regulation of applications of nuclear energy and related ancillary systems] (open access)

Workshop on environmental assessment. [Regulation of applications of nuclear energy and related ancillary systems]

Objectives of the workshop were: to review and evaluate the state-of-the-art of environmental impact assessments as applied to the regulation of applications of nuclear energy and related ancillary systems; to identify areas where existing technology allows establishing acceptable methods or standard practices that will meet the requirements of the NRC regulations, standards and guides for both normal operations and off-standard conditions including accident considerations; to illuminate topics where existing models or analytical methods are deficient because of unverified assumptions, a paucity of empirical data, conflicting results reported in the literature or a need for observation of operation systems; to compile, analyze and synthesize a prioritized set of research needs to advance the state-of-the-art to the level which will meet all of the requirements of the Commission's regulations, standards and guides; and to develop bases for maintaining the core of regulatory guidance at the optimum level balancing technical capabilities with practical considerations of cost and value to the regulatory process. The discussion held in small group sessions on aquatic, atmospheric, and terrestrial pathways are presented. The following research needs were identified as common to all three groups: validation of models; characterization of source terms; development of screening techniques; basis for de …
Date: July 1, 1982
Creator: Watson, E.C. (comp.)
System: The UNT Digital Library
Microspectroscopy (open access)

Microspectroscopy

The boom in electron and ion microbeam methods, with its overwhelming proliferation of new methods (and acronyms) and eager exploitation of every available technological advance, has tended to obscure the very wide usage of the corresponding optical methods. These outgrowths of the enormous field of visual optical microscopy are, however, quite alive and kicking, and their unique capabilities are becoming more appreciated as more and more advanced optical technology is being applied to the field. This review of optical microprobe techniques includes uv-VIS absorption techniques, fluorescence microspectroscopy, Raman measurements, and other microprobes such as the infrared ones, scatter, and the various partially optical methods. Also discussed are technological advances that may impact these fields. The natural place of microspectroscopy is shown to be as a higher discrimination, lower resolution companion of electron and ion beam microprobes.
Date: July 1, 1982
Creator: Hirschfeld, T.
System: The UNT Digital Library
Application of Two-time Methods in Stellar Pulsations (open access)

Application of Two-time Methods in Stellar Pulsations

The method of two-time expansions is extended to include the effects of the outer, non-adiabatic layers in stellar pulsation. The evolution of pulsating stellar models can be examined, including the approach to limit cycle behavior. The method is demonstrated by a calculation of the eigenvectors for a ..beta.. Cepheid model. It is argued that the method is promising as a practical tool for treating the approach to limiting oscillations, as well as resonant and multimode behavior.
Date: July 28, 1982
Creator: Pesnell, W. Dean; Regev, Oded & Buchler, J. Robert
System: The UNT Digital Library
Some preliminary views of plasma interaction: electromagnetic-launch systems (open access)

Some preliminary views of plasma interaction: electromagnetic-launch systems

This discussion outlines a few areas of fundamental research which appear vital for progress in developing advanced propulsion concepts using dc railgun thrusters. We have placed emphasis on the following: (1) dense plasma and high current density influences on changes in microstructure and properties of conventional rail conductors such as Cu, Al, and W alloys or composites; (2) the influences described in (1) on more advanced high temperature, microstrain resistant, materials such as amorphous tungsten; (3) location, description and temporal evolution of current, magnetic field, and losses during intense plasma-current field interactions with conductors; and (4) composite materials and sequentially sectioned structures for more efficient EM dc launcher configuration.
Date: July 14, 1982
Creator: Buckingham, Alfred C. & Hawke, Ronald S.
System: The UNT Digital Library
Investigation of other operating points for the RCA streak tube in the Lawrence Livermore National Laboratory streak camera (open access)

Investigation of other operating points for the RCA streak tube in the Lawrence Livermore National Laboratory streak camera

The soft x-ray streak camera uses the RCA C73435 streak tube body fitted with a removable x-ray cathode. The front of the streak tube is exposed to the vacuum of an experimental chamber, which is not entirely under the control of a streak camera operator. Occasionally, the vacuum becomes poor enough to cause corona and arcing from the cathode to the chamber wall. The corona problem is more difficult because the dimensions of the x-ray camera body are smaller than for the optical camera body. Therefore, we investigated the effects on camera performance of decreasing the accelerating voltage at the cathode from the customary 17 kV. Several operating points were evaluated and 12 kV cathode-to-anode with 5 kV cathode-to-grid were selected for more detailed investigation. Transverse spatial resolution and dynamic range were found to be essentially the same as at our normal operating point of 17 kV for the cathode and 2500 V on the grid. Magnification, sweep linearity and absolute sensitivity changed as expected. In the course of the investigation, we measured the dynamic range with our CCD readout system. The effect of Coulomb repulsion at the crossover point was also measured and found not to affect dynamic range.
Date: July 1, 1982
Creator: Thomas, S. W.; Peterson, R. L. & Griffith, R. L.
System: The UNT Digital Library
Investigations of glass structure using fluorescence line narrowing and moleuclar dynamics simulations (open access)

Investigations of glass structure using fluorescence line narrowing and moleuclar dynamics simulations

The local structure at individual ion sites in simple and multicomponent glasses is simulated using methods of molecular dynamics. Computer simulations of fluoroberyllate glasses predict a range of ion separations and coordination numbers that increases with increasing complexity of the glass composition. This occurs at both glass forming and glass modifying cation sites. Laser-induced fluorescence line-narrowing techniques provide a unique probe of the local environments of selected subsets of ions and are used to measure site to site variations in the electronic energy levels and transition probabilities of rare earth ions. These and additional results from EXAFS, neutron and x-ray diffraction, and NMR experiments are compared with simulated glass structures.
Date: July 2, 1982
Creator: Weber, M. J. & Brawer, S. A.
System: The UNT Digital Library