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Solar Energy System Performance Evaluation: seasonal report for Wormser, Columbia, South Carolina (open access)

Solar Energy System Performance Evaluation: seasonal report for Wormser, Columbia, South Carolina

The Wormser Solar Energy System located in a four unit townhouse apartment (5400 square feet) in Columbia, South Carolina was designed to provide 50% of the hot water and 70% of the space heating by the Wormser Scientific Corporation, Stamford, Connecticut. The Solar Energy System consists of 266 ft/sup 2/ of pyramidal optics, flat-plate liquid collectors, a solar window area of 1152 ft/sup 2/, a 2500 gallon thermal water storage tank, an energy transport system (water), heat exchangers, pumps, controls and four domestic hot water (DHW) tanks. Electrical elements in each domestic hot water tank provide necessary auxiliary energy for hot water. Four multifunctional heat pumps, supplied with solar heated water provide space heating energy to the apartments, collector freeze protection is provided through the location of the collectors inside the attic. The system with six modes of operation became oprational in February 1978. The following topics are discussed: system description, performance assessment, operating energy, energy savings, maintenance, summary and conclusions.
Date: August 1, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Exact integrability in quantum field theory (open access)

Exact integrability in quantum field theory

The treatment of exactly integrable systems in various branches of two-dimensional classical and quantum physics has recently been placed in a unified framework by the development of the quantum inverse method. This method consolidates a broad range of developments in classical nonlinear wave (soliton) physics, statistical mechanics, and quantum field theory. The essential technique for analyzing exactly integrable quantum systems was invested by Bethe in 1931. The quantum-mechanical extension of the inverse scattering method and its relationship to the methods associated with Bethe's ansatz are examined here. (RWR)
Date: August 1, 1980
Creator: Thacker, H.B.
Object Type: Article
System: The UNT Digital Library
Implementation of a hidden line and surface algorithm (open access)

Implementation of a hidden line and surface algorithm

The implementation of a 3-dimensional hidden line and surface algorithm discussed by Hamlin and Gear (NASA Langley Research Report 77-1) is described, and its advantages and disadvantages are examined. This algorithm is organized so that data can be preprocessed to speed display computations and so that the display is generated in a form suitable for a raster scan, refresh display. The version of the program described here is a hidden-line program, but the underlying algorithm is the same for both. 11 figures, 3 tables.
Date: August 1, 1980
Creator: Schweitzer, M.L.
Object Type: Report
System: The UNT Digital Library
Time and space dependency of radiative transfer in magnesium (open access)

Time and space dependency of radiative transfer in magnesium

Radiative transfer in a magnesium vapor has been studied. The experimental cell was designed to provide stable density measurements with a ..delta..lambda/sup -2/ variation with respect to the magnesium resonance line, which indicated pure Rayleigh scattering and no evidence of impurities. Total intensity measurements show the radiation field to be highly anisotropic, although somewhat less at late times. 8 refs., 7 figs. (WRF).
Date: August 1, 1986
Creator: Cooper, J.
Object Type: Report
System: The UNT Digital Library
Accommodation project for physically restricted personnel. Phase II. Low back project (open access)

Accommodation project for physically restricted personnel. Phase II. Low back project

This report presents a course outline and its associated criteria for a Back Pain Prevention Program for Sandia National Laboratories.
Date: August 1, 1982
Creator: Young, L. L. & Mossman, P. B.
Object Type: Report
System: The UNT Digital Library
Energy from true in situ processing of Antrim Shale: extraction trials in an explosively fractured site (open access)

Energy from true in situ processing of Antrim Shale: extraction trials in an explosively fractured site

Three in situ energy extraction trials were conducted at The Dow Chemical Company's oil shale site, in Michigan's Sanilac County, near the town of Peck. Here the Antrim shale layer occurs between 1200 and 1400 feet underground. The trials began on October 14, 1979, and ended on April 1, 1980. The three trials, lasting 7, 60 and 17 days respectively, were conducted in a formation prepared by explosive fracturing. Ignition energy was generated with a methane burner. Some energy in the form of a dilute fuel gas (5 to 50 btu/scf) was recovered in each trial but upon ignition drastic decreases in flow communication occurred between injection and production wells. That problem prevented the planned exploration of techniques which would raise the energy value of the production gas. Upon cool down of the formation after each trial, air permeability tests showed inter-well communication levels returning to near preburn levels. Thermal expansion is the most likely cause of the reduced permeability experienced under retorting conditions.
Date: August 1, 1980
Creator: VanDerPloeg, M.L.; Peil, C.A.; Kinkel, C.G.; Pihlaja, R.K.; Murdick, D.A.; Frost, J.R. et al.
Object Type: Report
System: The UNT Digital Library
NDA technology for uranium resource evaluation. Progress report July 1-December 31, 1979. [Gamma spectra calculations; field prototype photoneutron logging probe] (open access)

NDA technology for uranium resource evaluation. Progress report July 1-December 31, 1979. [Gamma spectra calculations; field prototype photoneutron logging probe]

This report describes work performed during the time period from July 1, 1979 to December 31, 1979, on the contract for Nondestructive Nuclear Analysis (NDA) Technology for Uranium Resource Evaluation in Group Q-1. Calculational effort was focused on improving the accuracy with which detector response function maps can be generated for subsequent enfolding with ONETRAN angular flux data. Experimental effort was highlighted by a field test of the prototype photoneutron logging probe at the Grand Junction DOE calibration facility. The probe demonstrated adequate durability in the field and sufficient sensitivity to uranium to function at competitive logging speeds.
Date: August 1, 1980
Creator: Evans, M.L.
Object Type: Report
System: The UNT Digital Library
Site insolation and wind power characteristics: technical report western region (north section) (open access)

Site insolation and wind power characteristics: technical report western region (north section)

This phase of the Site Insolation and Wind Power Characteristics Study was performed to provide statistical information on the expected future availability of solar and wind power at various sites in the Western Region (North Section) of the US Historic data (SOLMET), at 21 National Weather Service stations with hourly solar insolation and collateral meteorological information, were interrogated to provide an estimate of future trends. Solar data are global radiation incident on a horizontal surface, and wind data represent wind power normal to the air flow. Selected insolation and wind power conditions were investigated for their occurrence and persistence, for defined periods of time, on a monthly basis. Global horizontal insolation is related to inclined surfaces at each site. Ratios are provided, monthly, for multiplying global insolation to obtain insolation estimates on south-facing surfaces inclined at different angles with respect to the horizontal. Also, joint probability distribution tables are constructed showing the number of occurrences, out of a finite sample size, of daily average solar and wind power within selected intervals, by month. Information of this nature is intended as an aid to preliminary planning activities for the design and operation of solar and wind energy utilization and conversion systems.
Date: August 1, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Photoemission from solids: the transition from solid-state to atomic physics (open access)

Photoemission from solids: the transition from solid-state to atomic physics

As the photon energy is increased, photoemission from solids undergoes a slow transition from solid-state to atomic behavior. However, throughout the energy range h..nu.. = 10 to 1000 eV or higher both types of phenomena are present. Thus angle-resolved photoemission can only be understood quantitatively if each experimenter recognizes the presence of band-structure, photoelectron diffraction, and photoelectron asymmetry effects. The quest for this understanding will build some interesting bridges between solid-state and atomic physics and should also yield important new insights about the phenomena associated with photoemission.
Date: August 1, 1980
Creator: Shirley, D.A.
Object Type: Article
System: The UNT Digital Library
Site insolation and wind power characteristics: technical report western region (south section) (open access)

Site insolation and wind power characteristics: technical report western region (south section)

This phase of the Site Insolation and Wind Power Characteristics Study was performed to provide statistical information on the expected future availability of solar and wind power at various sites in the Western Region (South Section) of the US Historic data (SOLMET), at 22 National Weather Service stations with hourly solar insolation and collateral meteorological information, were interrogated to provide an estimate of future trends. Solar data are global radiation incident on a horizontal surface, and wind data represent wind power normal to the air flow. Selected insolation and wind power conditions were investigated for their occurrence and persistence, for defined periods of time, on a monthly basis. Global horizontal insolation is related to inclined surfaces at each site. Ratios are provided, monthly, for multiplying global insolation to obtain insolation estimates on south-facing surfaces inclined at different angles with respect to the horizontal. Also, joint probability distribution tables are constructed showing the number of occurrences, out of a finite sample size, of daily average solar and wind power within selected intervals, by month. Information of this nature is intended as an aid to preliminary planning activities for the design and operation of solar and wind energy utilization and conversion systems.
Date: August 1, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Measurement of Inclusive Eta Production in e/sup +/e/sup -/ Interactions Near Charm Threshold (open access)

Measurement of Inclusive Eta Production in e/sup +/e/sup -/ Interactions Near Charm Threshold

The inclusive cross section for eta production in e/sup +/e/sup -/ interactions near charm threshold was measured by use of the Crystal Ball detector at SPEAR. By comparison of the inclusive eta production above and below charm threshold the following limits were obtained: R(e/sup +/e/sup -/ ..-->.. F anti FX)BR(F ..-->.. eta x) < 0.3 (90% C.L., E/sub cm/ < 4.5 GeV); BR(D ..-->.. eta x) < 0.13 (90% C.L., averaged over charged and neutral D components of the psi''). 4 figures, 1 table.
Date: August 1, 1980
Creator: Porter, F. C.
Object Type: Article
System: The UNT Digital Library
Multilayer optical elements for generation and analysis of circularly polarized x-rays (open access)

Multilayer optical elements for generation and analysis of circularly polarized x-rays

Calculations of the relative phase changes of {sigma} and {pi} electric field components on Bragg reflection from and transmission through multilayers are presented. Large relative phase changes can be calculated in certain cases, which may lead to utility of multilayers as quarter-wave plates for generation and analysis of circularly polarized soft x-radiation. Similar behavior may be expected for perfect crystals in the hard x-ray range. 24 refs., 4 figs.
Date: August 1, 1989
Creator: Kortright, J.B. & Underwood, J.H.
Object Type: Article
System: The UNT Digital Library
Environmental radiation safety: source term modification by soil aerosols. Interim report (open access)

Environmental radiation safety: source term modification by soil aerosols. Interim report

The goal of this project is to provide information useful in estimating hazards related to the use of a pure refractory oxide of /sup 238/Pu as a power source in some of the space vehicles to be launched during the next few years. Although the sources are designed and built to withstand re-entry into the earth's atmosphere, and to impact with the earth's surface without releasing any plutonium, the possibility that such an event might produce aerosols composed of soil and /sup 238/PuO/sub 2/ cannot be absolutely excluded. This report presents the results of our most recent efforts to measure the degree to which the plutonium aerosol source term might be modified in a terrestrial environment. The five experiments described represent our best effort to use the original experimental design to study the change in the size distribution and concentration of a /sup 238/PuO/sub 2/ aerosol due to coagulation with an aerosol of clay or sandy loam soil.
Date: August 1, 1980
Creator: Moss, O.R.; Allen, M.D.; Rossignol, E.J. & Cannon, W.C.
Object Type: Report
System: The UNT Digital Library
Thin film cadmium telluride solar cells. Final technical report, July 1, 1979-August 31, 1980 (open access)

Thin film cadmium telluride solar cells. Final technical report, July 1, 1979-August 31, 1980

Efforts during this program have been directed to the construction of apparatus for the chemical vapor deposition of cadmium telluride films, the selection and preparation of substrates, the deposition and characterization of cadmium telluride films, and the fabrication and characterization of solar cells. Cadmium telluride films have been deposited on a number of substrates by the direct combination of cadmium and tellurium on the substrate surface at 500/sup 0/C or higher at rates of up to 0.6 ..mu..m/min. The structural, crystallographic, and electrical properties of cadmium telluride films deposited over a wide range of conditions have been evaluated. A series of doping experiments have been carried out using iodine and indium as the n-type dopant, and phosphorus, arsenic, and antimony as the p-type dopant. Low resistivity films have not been produced thus far. In/W/graphite substrates have been used for the deposition of n-type films with an ohmic interface. However, no suitable substrates have been found to form an ohmic interface with p-type films. Solar cells prepared from these films exhibit relatively good short-circuit current density, up to 15 mA/cm/sup 2/, but their conversion efficiencies are severely limited by the high series resistance of the devices. It is believed that low …
Date: August 1, 1980
Creator: Chu, T. L.
Object Type: Report
System: The UNT Digital Library
Volume dependence of computed grain boundary energy (open access)

Volume dependence of computed grain boundary energy

Over the past five years there have been numerous studies of grain boundary structure using the method of computer molecular statics which assume pairwise central potentials for the interatomic interaction. Emphasis is usually placed on relative grain boundary energies but these may be inaccurate due to various, but related, approximations and constraints implicity imposed on the calculation-namely central forces, finite model size, fixed border conditions and volume dependent contributions to the energy of the system. It is the purpose of this work to clarify how these particular properties of the model can affect the computed grain boundary energy and demonstrate instances in which the quoted energy has strictly been inaccurate. The implication of these results, especially on how they affect the method of relaxation and the resulting grain boundary structure is discussed.
Date: August 1, 1980
Creator: Bristowe, P.D. & Brokman, A.
Object Type: Report
System: The UNT Digital Library
Deburring small intersecting holes (open access)

Deburring small intersecting holes

Deburring intersecting holes is one of the most difficult deburring tasks faced by many industries. Only 14 of the 37 major deburring processes are applicable to most intersecting hole applications. Only five of these are normally applicable to small or miniature holes. Basic process capabilities and techniques used as a function of hole sizes and intersection depths are summarized.
Date: August 1, 1980
Creator: Gillespie, LaRoux K.
Object Type: Report
System: The UNT Digital Library
Fermilab Tevatron and Pbar source status report (open access)

Fermilab Tevatron and Pbar source status report

The antiproton production cycle is enumerated, and the commissioning of the antiproton source is described, giving milestones and major obstacles. The Tevatron collider operation is described, including procedure to load the Tevatron with three bunches of protons and three bunches of antiprotons. Commissioning of the Main Ring and Tevatron for collider operation is described. Development and accelerator studies in four areas were necessary: main ring RF manipulations; controls and applications software support; Tevatron storage and low-beta squeeze sequence; and study of various beam transfers, storage steps, and sequences. Final tests are described. A long range upgrade program is presently under evaluation to accomplish these goals: luminosity increase to 5 x 10/sup 31/ cm/sup -2/sec/sup -1/, production rates up to 4 x 10/sup 11/ antiprotons/hr, and intensity increase for fixed target operation. Beam quality is to be improved by the injector and main ring upgrades, and the luminosity goal is addressed by the Collider upgrade. (LEW)
Date: August 1, 1986
Creator: Edwards, H.
Object Type: Article
System: The UNT Digital Library
Raman microprobe investigation of molecular structure and organization in the native state of woody tissue (open access)

Raman microprobe investigation of molecular structure and organization in the native state of woody tissue

Although the primary emphasis of our program has remained with the application of Raman spectroscopy to the study of native tissue, the scope of the work has been expanded to include a number of complementary approaches. These have included Solid State 13C NMR, autoradiography of radiolabeled woody tissue sections, and the generation of biomimetic tertiary aggregates which simulate states of aggregation characteristic of cell walls. Our Raman spectroscopic studies have resulted in progress in the areas of interpretation of the spectral features, and confirmation of the variability of the patterns of orientation of lignin reported earlier. We have assembled and made operational our new microprobe and spectrometer systems acquired under the DOE-URIP program. We have also demonstrated that, operating with gated detection and pulsed laser excitation, we can discriminate against the laser-excited fluorescence characteristic of most woody tissue. Our studies of celluloses, which combine Raman spectroscopy and 13C NMR have shown that all native celluloses are composites of two forms which have the same secondary structure but different tertiary structures.
Date: August 1, 1989
Creator: Atalla, R.H.
Object Type: Report
System: The UNT Digital Library
Physics at hadron colliders: Experimental view (open access)

Physics at hadron colliders: Experimental view

The physics of the hadron-hadron collider experiment is considered from an experimental point of view. The problems encountered in determination of how well the standard model describes collider results are discussed. 53 refs., 58 figs.
Date: August 1, 1987
Creator: Siegrist, J.L.
Object Type: Article
System: The UNT Digital Library
Study of federal microwave standards (open access)

Study of federal microwave standards

Present and future federal regulatory processes which may impact the permissible levels of microwave radiation emitted by the SPS Microwave Power Transmission (MPTS) were studied. An historical development of US occupational and public microwave standards includes an overview of Western and East European philosophies of environmental protection and neurophysiology which have led to the current widely differing maximum permissible exposure limits to microwaves. The possible convergence of microwave standards is characterized by a lowering of Western exposure levels while Eastern countries consider standard relaxation. A trend toward stricter controls on activities perceived as harmful to public health is under way as is interest in improving the federal regulatory process. Particularly relevant to SPS is the initiation of long-term, low-level microwave exposure programs. Coupled with new developments in instrumentation and dosimetry, the results from chronic exposure program and population exposure studies could be expected within the next five to ten years. Also discussed is the increasing public concern that rf energy is yet another hazardous environmental agent.
Date: August 1, 1980
Creator: David, L.
Object Type: Report
System: The UNT Digital Library
Laser cutting plastic materials (open access)

Laser cutting plastic materials

A 1000-watt CO/sub 2/ laser has been demonstrated as a reliable production machine tool for cutting of plastics, high strength reinforced composites, and other nonmetals. More than 40 different plastics have been laser cut, and the results are tabulated. Applications for laser cutting described include fiberglass-reinforced laminates, Kevlar/epoxy composites, fiberglass-reinforced phenolics, nylon/epoxy laminates, ceramics, and disposable tooling made from acrylic.
Date: August 1, 1980
Creator: Van Cleave, R.A.
Object Type: Report
System: The UNT Digital Library
Physicochemical basis of the Na-K-Ca geothermometer (open access)

Physicochemical basis of the Na-K-Ca geothermometer

Regular changes in solution composition were observed experimentally during granite reaction with dilute NaCl (+CaCl/sub 2/) solutions; these changes closely follow the empirical Na-K-Ca geothermometer relationship. Initial minerals forming the granite (quartz, plagioclase, K-feldspar, and biotite) were etched by the reactions. Alteration phases formed include calcium-zeolite at <300/sup 0/C, feldspar overgrowths at >300/sup 0/C, and minor amounts of clay and calcsilicate at all temperatures. Amphibole overgrowths were also found at 340/sup 0/C. Quartz is near saturation in all experiments, and preliminary calculations of aqueous species distributions and mineral affinities indicate that the solutions achieve super-saturation with feldspars as the temperature increase. A consistent variation attributable to pH differences was observed in the empirical geothermometer relationship for all experimental data. At 340/sup 0/C, the experimental solutions appear to have deviated slightly from the empirical Na-K-Ca relationship. Such deviations may also be found in natural systems that attain such temperatures.
Date: August 1, 1986
Creator: Janecky, D. R.; Charles, R. W.; Bayhurst, Gregory K. & Benjamin, T. M.
Object Type: Report
System: The UNT Digital Library
An assessment of the effects of radiation on permanent magnet material in the ALS (Advanced Light Source) insertion devices (open access)

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

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 away from the electron beam during operation. This material, which is preferred because of its high remanence, is known to be more sensitive to radiation than some other magnetic materials. Simple energy loss estimates and the EGS4 code were used to estimate the radiation levels in the ALS insertion devices in the regions of the magnetic materials. The radiation levels were estimated for both aluminum and stainless steel vacuum chambers to determine if one would provide significantly better shielding. We conclude that Nd-Fe-B can be used in the ALS insertion devices and that there is little difference in the radiation levels for aluminum and stainless vacuum vessels. 8 refs., 7 figs., 1 tab.
Date: August 1, 1989
Creator: Hassenzahl, W. V.; Jenkins, T. M.; Namito, Y.; Nelson, W. R. & Swanson, W. P.
Object Type: Article
System: The UNT Digital Library
Convective heat transport in geothermal systems (open access)

Convective heat transport in geothermal systems

Most geothermal systems under exploitation for direct use or electrical power production are of the hydrothermal type, where heat is transferred essentially by convection in the reservoir, conduction being secondary. In geothermal systems, buoyancy effects are generally important, but often the fluid and heat flow patterns are largely controlled by geologic features (e.g., faults, fractures, continuity of layers) and location of recharge and discharge zones. During exploitation, these flow patterns can drastically change in response to pressure and temperature declines, and changes in recharge/discharge patterns. Convective circulation models of several geothermal systems, before and after start of fluid production, are described, with emphasis on different characteristics of the systems and the effects of exploitation on their evolution. Convective heat transport in geothermal fields is discussed, taking into consideration (1) major geologic features; (2) temperature-dependent rock and fluid properties; (3) fracture- versus porous-medium characteristics; (4) single- versus two-phase reservoir systems; and (5) the presence of noncondensible gases.
Date: August 1, 1986
Creator: Lippmann, M.J. & Bodvarsson, G.S.
Object Type: Article
System: The UNT Digital Library