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0-G experiments with advanced ceramic fabric wick structures (open access)

0-G experiments with advanced ceramic fabric wick structures

Both Air Force and NASA future spacecraft thermal management needs span the temperature range from cryogenic to liquid metals. Many of these needs are changing and not well defined and will remain so until goals, technology, and missions converge. Nevertheless, it is certain that high-temperature (> 800 K) and medium-temperature (about 450 K) radiator systems will have to be developed that offer significant improvements over current designs. This paper discusses experiments performed in the lower temperature regime as part of a comprehensive advanced ceramic fabric (ACF) heat pipe development program. These experiments encompassed wicking tests with various ceramic fabric samples, and heat transfer tests with a 1-m long prototype ACF water heat pipe. A prototype ceramic fabric/titanium water heat pipe has been constructed and tested; it transported up to 60 W of power at about 390 K. Startup and operation both with and against gravity examined. Wick testing was begun to aid in the design and construction of an improved prototype heat pipe, with a 38-{mu}m stainless steel linear covered by a biaxially-braided Nextel (trademark of the 3M Co., St. Paul, Minnesota) sleeve that is approximately 300-{mu}m thick. Wick testing took place in 1-g; limited testing in 0-g was initiated, …
Date: July 1991
Creator: Antoniak, Z. I.; Webb, B. J.; Bates, J. M.; Cooper, M. F. & Pauley, K. A.
Object Type: Article
System: The UNT Digital Library
A 2-D imaging heat-flux gauge (open access)

A 2-D imaging heat-flux gauge

This report describes a new leadless two-dimensional imaging optical heat-flux gauge. The gauge is made by depositing arrays of thermorgraphic-phosphor (TP) spots onto the faces of a polymethylpentene is insulator. In the first section of the report, we describe several gauge configurations and their prototype realizations. A satisfactory configuration is an array of right triangles on each face that overlay to form squares when the gauge is viewed normal to the surface. The next section of the report treats the thermal conductivity of TPs. We set up an experiment using a comparative longitudinal heat-flow apparatus to measure the previously unknown thermal conductivity of these materials. The thermal conductivity of one TP, Y{sub 2}O{sub 3}:Eu, is 0.0137 W/cm{center dot}K over the temperature range from about 300 to 360 K. The theories underlying the time response of TP gauges and the imaging characteristics are discussed in the next section. Then we discuss several laboratory experiments to (1) demonstrate that the TP heat-flux gauge can be used in imaging applications; (2) obtain a quantum yield that enumerates what typical optical output signal amplitudes can be obtained from TP heat-flux gauges; and (3) determine whether LANL-designed intensified video cameras have sufficient sensitivity to acquire …
Date: July 1, 1991
Creator: Noel, B.W.; Borella, H.M. (Los Alamos National Lab., NM (United States)); Beshears, D.L.; Sartory, W.K.; Tobin, K.W.; Williams, R.K. (Oak Ridge National Lab., TN (United States)) et al.
Object Type: Report
System: The UNT Digital Library
9-1-1 Caller, Volume 3, Number 3, July/August 1991 (open access)

9-1-1 Caller, Volume 3, Number 3, July/August 1991

Bimonthly newsletter of the Texas Advisory Commission on State Emergency Communications discussing news and activities of the organization as well as other information related to 9-1-1 services and other emergency communication within Texas.
Date: July 1991
Creator: Texas. Advisory Commission on State Emergency Communications.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Adoption, Implementation and Enforcement of Commercial Building Energy Codes in New Mexico and Arizona (open access)

Adoption, Implementation and Enforcement of Commercial Building Energy Codes in New Mexico and Arizona

The US Department of Energy (DOE) is considering ways to encourage states to adopt energy efficiency standards for residential and commercial buildings in the private sector. Such standards are now mandatory for federal buildings, and for private buildings in 34 states; in the remaining 16 states, the standards serve as guidelines for voluntary compliance. In this study for DOE, Pacific Northwest Laboratory (PNL) assessed the process by which energy codes for commercial buildings were adopted and implemented in Arizona and New Mexico. Information was gathered primarily through a series of interviews with state officials, city building officials, architects and engineers, builders, and staff from utilities in the two states. Until other state processes are studied, the extent of the similarities and dissimilarities to the situation in New Mexico and Arizona are unknown. A more extensive study may show that at least some elements of the two state's experience have been paralleled in other parts of the country. General strategies to encourage the adoption of energy codes, assist implementation, and support enforcement were developed based on the research from Arizona and New Mexico and are presented in this report. 6 refs., 4 figs.
Date: July 1, 1991
Creator: Callaway, J. W.; Thurman, A G & Shankle, D L
Object Type: Report
System: The UNT Digital Library
Adsorption of chromate/organic-acid mixtures in aquifer materials (open access)

Adsorption of chromate/organic-acid mixtures in aquifer materials

The overall objective of this project is to develop a fuller understanding of the interactions of mixtures of anionic co-contaminants with oxide-mineral surfaces. Our specific focus is on the competitive interactions of chromate and oxalic acid on ferric oxyhydroxide and on natural aquifer materials. Chromate and oxalate are of practical interest as widespread contaminants at many DOE facilities. However, these anions also are excellent model adsorbates for elucidating fundamental aspects of ionic adsorption processes, particularly with respect to organic acids.
Date: July 15, 1991
Creator: Fish, W. & Palmer, C.D.
Object Type: Report
System: The UNT Digital Library
Adsorption of chromate/organic-acid mixtures in aquifer materials. Technical progress report, 1 July 1990--30 June 1991 (open access)

Adsorption of chromate/organic-acid mixtures in aquifer materials. Technical progress report, 1 July 1990--30 June 1991

The overall objective of this project is to develop a fuller understanding of the interactions of mixtures of anionic co-contaminants with oxide-mineral surfaces. Our specific focus is on the competitive interactions of chromate and oxalic acid on ferric oxyhydroxide and on natural aquifer materials. Chromate and oxalate are of practical interest as widespread contaminants at many DOE facilities. However, these anions also are excellent model adsorbates for elucidating fundamental aspects of ionic adsorption processes, particularly with respect to organic acids.
Date: July 15, 1991
Creator: Fish, W. & Palmer, C. D.
Object Type: Report
System: The UNT Digital Library
Advanced Coal Conversion Process Demonstration (Project) (open access)

Advanced Coal Conversion Process Demonstration (Project)

This report contains a description of technical progress made on the Advanced Coal Conversion Process Demonstration Project (ACCP). The project is a US Department of Energy Innovative Clean Coal Technology Project. The cooperative agreement defining the project is between DOE and the Rosebud SynCoal Partnership RSCP. The RSCP is a partnership between Western Energy Company (WECo), a subsidiary of Entech, Montana Power's non-utility group, and NRG, a subsidiary of Northern States Power. The ACCP is a method of upgrading low ranked coals by reducing the moisture and sulfur content and increasing the heating value. The facility is being constructed at WECo's Rosebud No. 6 coal mine, west of Colstrip, Montana. This report contains both a history of the process development and a report of technical progress made since the beginning of the Clean Coal 1 cooperative agreement.
Date: July 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advanced coal-fueled industrial cogeneration gas turbine system (open access)

Advanced coal-fueled industrial cogeneration gas turbine system

Advances in coal-fueled gas turbine technology over the past few years, together with recent DOE-METC sponsored studies, have served to provide new optimism that the problems demonstrated in the past can be economically resolved and that the coal-fueled gas turbine can ultimately be the preferred system in appropriate market application sectors. The objective of the Solar/METC program is to prove the technical, economic, and environmental feasibility of a coal-fired gas turbine for cogeneration applications through tests of a Centaur Type H engine system operated on coal fuel throughout the engine design operating range. The five-year program consists of three phases, namely: (1) system description; (2) component development; (3) prototype system verification. A successful conclusion to the program will initiate a continuation of the commercialization plan through extended field demonstration runs.
Date: July 1, 1991
Creator: LeCren, R. T.; Cowell, L. H.; Galica, M. A.; Stephenson, M. D. & Wen, C. S.
Object Type: Report
System: The UNT Digital Library
Advanced coal-fueled industrial cogeneration gas turbine system. Annual report, June 1990--June 1991 (open access)

Advanced coal-fueled industrial cogeneration gas turbine system. Annual report, June 1990--June 1991

Advances in coal-fueled gas turbine technology over the past few years, together with recent DOE-METC sponsored studies, have served to provide new optimism that the problems demonstrated in the past can be economically resolved and that the coal-fueled gas turbine can ultimately be the preferred system in appropriate market application sectors. The objective of the Solar/METC program is to prove the technical, economic, and environmental feasibility of a coal-fired gas turbine for cogeneration applications through tests of a Centaur Type H engine system operated on coal fuel throughout the engine design operating range. The five-year program consists of three phases, namely: (1) system description; (2) component development; (3) prototype system verification. A successful conclusion to the program will initiate a continuation of the commercialization plan through extended field demonstration runs.
Date: July 1, 1991
Creator: LeCren, R. T.; Cowell, L. H.; Galica, M. A.; Stephenson, M. D. & Wen, C. S.
Object Type: Report
System: The UNT Digital Library
Advanced nuclear reactor public opinion project (open access)

Advanced nuclear reactor public opinion project

This Interim Report summarizes the findings of our first twenty in-depth interviews in the Advanced Nuclear Reactor Public Opinion Project. We interviewed 6 industry trade association officials, 3 industry attorneys, 6 environmentalists/nuclear critics, 3 state officials, and 3 independent analysts. In addition, we have had numerous shorter discussions with various individuals concerned about nuclear power. The report is organized into the four categories proposed at our April, 1991, Advisory Group meeting: safety, cost-benefit analysis, science education, and communications. Within each category, some change of focus from that of the Advisory Group has been required, to reflect the findings of our interviews. This report limits itself to describing our findings. An accompanying memo draws some tentative conclusions.
Date: July 25, 1991
Creator: Benson, B.
Object Type: Report
System: The UNT Digital Library
Advanced nuclear reactor public opinion project. Interim report (open access)

Advanced nuclear reactor public opinion project. Interim report

This Interim Report summarizes the findings of our first twenty in-depth interviews in the Advanced Nuclear Reactor Public Opinion Project. We interviewed 6 industry trade association officials, 3 industry attorneys, 6 environmentalists/nuclear critics, 3 state officials, and 3 independent analysts. In addition, we have had numerous shorter discussions with various individuals concerned about nuclear power. The report is organized into the four categories proposed at our April, 1991, Advisory Group meeting: safety, cost-benefit analysis, science education, and communications. Within each category, some change of focus from that of the Advisory Group has been required, to reflect the findings of our interviews. This report limits itself to describing our findings. An accompanying memo draws some tentative conclusions.
Date: July 25, 1991
Creator: Benson, B.
Object Type: Report
System: The UNT Digital Library
Advanced photon source proposal for upgrading the radiation safety of x-ray labs (open access)

Advanced photon source proposal for upgrading the radiation safety of x-ray labs

There are two adjacent x-ray labs in building 360, each having two entrance doors. Lab A240 has two x-ray machines and lab A248 has one. All machines are equipped with sliding safety windows and microswitches to monitor the state of the windows - open or closed. Two modes of operation are possible. (1) Secure Mode in which all safety windows are closed as indicated by the microswitches. This satisfies the interlock system, allowing the high voltage power supply to be turned on. (2) Bypass Mode in which the interlock system is overridden by a key-controlled selector switch and high voltage can be turned on with machine hutch window(s) open. The bypass mode is potentially unsafe because it is possible for an operator to leave a running instrument unattended while the windows are open. Thus, it is possible for someone entering the lab to expose themselves to x-rays.
Date: July 1, 1991
Creator: Friedman, N.
Object Type: Report
System: The UNT Digital Library
Agitation within Mk-42 insert caused by air sparge (open access)

Agitation within Mk-42 insert caused by air sparge

Dissolution of Rocky Flats Pu alloys and Pu metal using a nested insert'' configuration (One Well Insert (S-3352) inside the Mk-42 Insert) will require a Nuclear Safety Study, a major assumption of which will be that the annular dissolver is well-mixed. The well-mixed'' assumption was theoretically and experimentally supported for alloy dissolution using the Three Well Insert, but the present situation differs significantly. In the former case, the insert was directly exposed to the agitation induced by air sparging; in the case under consideration, the One Well Insert would be shielded by the Mk-42 Insert. In an effort to determine if the nested insert'' approach should be pursued, the past studies and technical literature have been surveyed and an attempt made to predict the extent of mixing and bulk circulation for a nested insert'' configuration in the presence of air sparging.
Date: July 12, 1991
Creator: Ramsey, C.J.
Object Type: Report
System: The UNT Digital Library
Agitation within Mk-42 insert caused by air sparge (open access)

Agitation within Mk-42 insert caused by air sparge

Dissolution of Rocky Flats Pu alloys and Pu metal using a ``nested insert`` configuration (One Well Insert (S-3352) inside the Mk-42 Insert) will require a Nuclear Safety Study, a major assumption of which will be that the annular dissolver is well-mixed. The ``well-mixed`` assumption was theoretically and experimentally supported for alloy dissolution using the Three Well Insert, but the present situation differs significantly. In the former case, the insert was directly exposed to the agitation induced by air sparging; in the case under consideration, the One Well Insert would be shielded by the Mk-42 Insert. In an effort to determine if the ``nested insert`` approach should be pursued, the past studies and technical literature have been surveyed and an attempt made to predict the extent of mixing and bulk circulation for a ``nested insert`` configuration in the presence of air sparging.
Date: July 12, 1991
Creator: Ramsey, C. J.
Object Type: Report
System: The UNT Digital Library
Air Pathway Report: Phase I of the Hanford Environmental Dose Reconstruction Project (open access)

Air Pathway Report: Phase I of the Hanford Environmental Dose Reconstruction Project

Phase 1 of the air-pathway portion of the Hanford Environmental Dose Reconstruction (HEDR) Project sought to determine whether dose estimates could be calculated for populations in the 10 counties nearest the Hanford Site from atmospheric releases of iodine-131 from the site from 1944--1947. Phase 1 demonstrated the following: HEDR-calculated source-term estimates of iodine-131 releases to the atmosphere were within 20% of previously published estimates; calculated vegetation concentrations of iodine-131 agree well with previously published measurements; the highest of the Phase 1 preliminary dose estimates to the thyroid are consistent with independent, previously published estimates of doses to maximally exposed individuals; and, relatively crude, previously published measurements of thyroid burdens for Hanford workers are in the range of average burdens that the HEDR model estimated for similar reference individuals for the period 1944--1947. Preliminary median dose estimates summed over the year 1945--1947 for the primary pathway, air-pasture-cow-milk-thyroid, ranged from low median values of 0.006 rad for upwind adults who obtained milk from backyard cows not on pasture to high median values of 68.0 rad for downwind infants who drank milk from pasture-fed cows. Extremes of the estimated range are a low of essentially zero to upwind adults and a high of …
Date: July 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Algebraic calculation of stroboscopic maps of ordinary, nonlinear differential equations (open access)

Algebraic calculation of stroboscopic maps of ordinary, nonlinear differential equations

The relation between the parameters of a differential equation and corresponding discrete maps are becoming increasingly important in the study of nonlinear dynamical systems. Maps are well adopted for numerical computation and several universal properties of them are known. Therefore some perturbation methods have been proposed to deduce them for physical systems, which can be modeled by an ordinary differential equation (ODE) with a small nonlinearity. A new iterative, rigorous algebraic method for the calculation of the coefficients of a Taylor expansion of a stroboscopic map from ODE's with not necessarily small nonlinearities is presented. It is shown analytically that most of the coefficients are small for a small integration time and grow slowly in the course of time if the flow vector field of the ODE is polynomial and if the ODE has fixed point in the origin. Approximations of different orders respectively of the rest term are investigated for several nonlinear systems. 31 refs., 16 figs.
Date: July 25, 1991
Creator: Wackerbauer, R. (Max-Planck-Institut fuer Extraterrestrische Physik, Garching (Germany)); Huebler, A. (Illinois Univ., Urbana, IL (United States). Center for Complex Systems Research) & Mayer-Kress, G. (Los Alamos National Lab., NM (United States) California Univ., Santa Cruz, CA (United States). Dept. of Mathematics)
Object Type: Article
System: The UNT Digital Library
Algebraic modelling of components and computer simulation of refrigerator steady-state operation (open access)

Algebraic modelling of components and computer simulation of refrigerator steady-state operation

Because manufacturers of household refrigerators are facing two important problems, the replacement of refrigerant R12 and the need to improve efficiency, there is a need to develop a model of the refrigerator which greatly reduces the computer time required to evaluate the refrigeration cycle. This paper describes a refrigerator model where all equations are reduced to algebraic form. The model has the following features: (1) each component of the refrigerator is modelled separately, (2) all differential equations are reduced to algebraic equations, and (3) the transport properties of new refrigerants are not needed. The model can be used to: (1) evaluate new refrigerants as drop-in refrigerants, (2) study different refrigeration cycles and (3) optimize the refrigerator for each new refrigerant. This paper describes the development of the model and, where possible, the results of the model are compared to experimental data. 12 refs., 7 figs.
Date: July 1, 1991
Creator: Rogers, S. & Tree, D.
Object Type: Article
System: The UNT Digital Library
Amorphous silicon based radiation detectors (open access)

Amorphous silicon based radiation detectors

We describe the characteristics of thin(1 {mu}m) and thick (>30{mu}m) hydrogenated amorphous silicon p-i-n diodes which are optimized for detecting and recording the spatial distribution of charged particles, x-rays and {gamma} rays. For x-ray, {gamma} ray, and charged particle detection we can use thin p-i-n photosensitive diode arrays coupled to evaporated layers of suitable scintillators. For direct detection of charged particles with high resistance to radiation damage, we use the thick p-i-n diode arrays. 13 refs., 7 figs.
Date: July 1, 1991
Creator: Perez-Mendez, V.; Cho, G.; Drewery, J.; Jing, T.; Kaplan, S. N.; Qureshi, S. et al.
Object Type: Article
System: The UNT Digital Library
Analog synthesized fast-variable linear load (open access)

Analog synthesized fast-variable linear load

A several kilowatt power level, fast-variable linear resistor has been synthesized by using analog components to control the conductance of power MOSFETs. Risetimes observed have been as short as 500 ns with respect to the control signal and 1 to 2 {mu}s with respect to the power source voltage. A variant configuration of this load that dissipates a constant power set by a control signal is indicated. Replacement of the MOSFETs by SITs to increase power handling, speed and radiation hardness is discussed.
Date: July 1, 1991
Creator: Niedra, J. M.
Object Type: Report
System: The UNT Digital Library
Analogous behavior in the quantum hall effect, anyon superconductivity, and the standard model (open access)

Analogous behavior in the quantum hall effect, anyon superconductivity, and the standard model

Similarities between physical behavior known to occur, or suspected of occurring, in simple condensed matter systems and behavior postulated by the standard model are identified and discussed. Particular emphasis is given to quantum number fractionalization, spontaneous occurrence of gauge forces, spontaneous violation of P and T, and anomaly cancellation. 46 refs.
Date: July 1, 1991
Creator: Laughlin, R.B. (Stanford Univ., CA (United States). Dept. of Physics) & Libby, S.B. (Lawrence Livermore National Lab., CA (United States))
Object Type: Article
System: The UNT Digital Library
An analysis of grazing incidence metal mirrors in a laser ICF reactor driver (open access)

An analysis of grazing incidence metal mirrors in a laser ICF reactor driver

Grazing incidence metal mirrors (GIMMs) are examined to replace dielectric mirrors for the final elements in a laser beam line for an inertial confinement fusion reactor. For a laser driver with a wavelength from 250 to 500 nm in a 10-ms pulse, irradiated mirrors made of Al, Al alloys, or Mg were found to have calculated laser damage limits of 0.3--2.3 J/cm{sup 2} of beam energy and neutron lifetime fluence limits of over 5 {times} 10{sup 20} 14 MeV n/cm{sup 2} when used at grazing incidence and operated at room temperature or at 77 K. A final focusing system including mirrors made of Al alloy 7475 at room temperature or at liquid nitrogen temperatures used with a driver which delivers 5 MJ of beam energy in 32 beams would require 32 mirrors of roughly 10 m{sup 2} each. This chapter includes calculations of damage limits for GIMMs and discusses critical issues relevant to the integrity and lifetime of such mirrors in a reactor environment. The reflectivities of various metals are calculated from measured optical constants at room temperature and at cryogenic temperatures for 250- to 500-nm light at both normal and grazing incidence. Then, for the mirrors in a representative …
Date: July 12, 1991
Creator: Bieri, R. & Guinan, M.
Object Type: Report
System: The UNT Digital Library
Analysis of solvent evaporation effects in spin coating of colloidal oxide suspensions (open access)

Analysis of solvent evaporation effects in spin coating of colloidal oxide suspensions

The goal of our research this past year was to develop a theory for spin coating that accounts for solvent evaporation, film hydrodynamics, and the rheology of the colloidal suspension being coated. This report briefly discusses work toward this goal during the 1989 to 1990 funding year. (JL)
Date: July 23, 1991
Creator: Rehg, T. J. & Higgins, B. G.
Object Type: Report
System: The UNT Digital Library
Analysis, Volume 12, Number 7, July 1991 (open access)

Analysis, Volume 12, Number 7, July 1991

Periodic newsletter discussing information related to legislation, state finance, and other topics related to Texas government. This issue focuses on low SAT scores in Texas, including potential reasons, solutions, and more.
Date: July 1991
Creator: Texas Research League
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Ancillary operations in coal preparation instrumentation on-line low cost sulfur and ash analyzer (open access)

Ancillary operations in coal preparation instrumentation on-line low cost sulfur and ash analyzer

The purpose of this document is to define the testing to be performed on field collected coal slurry samples by ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectroscopy). A total of 20 samples (8 from an Upper Freeport coal and 12 from an Oklahoma coal) are to be analyzed in triplicate for the elements S, Si, Al, Fe, Ca, and Mg. For each of the two coal slurry types (Upper Freeport and Oklahoma), a container of slurry labeled calibration'' has been prepared. These calibration slurries may be used to get the system tuned'' (note that the volume of the field collected slurries is relatively small and cannot be used to tune'' the system). The calibration slurries were made from the slurry collected from the drain from the second sampling stage during the field testing.
Date: July 1, 1991
Creator: Malito, M. L.
Object Type: Report
System: The UNT Digital Library