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Novel duplex vapor-electrochemical method for silicon solar cells. Quarterly progress report No. 7, August 1, 1977--October 31, 1977 (open access)

Novel duplex vapor-electrochemical method for silicon solar cells. Quarterly progress report No. 7, August 1, 1977--October 31, 1977

Silicon obtained by the SiF/sub 4/-Na reaction was analyzed by spark source mass spectrometry (SSMS). A partial listing of the results is given below. The concentration units in parentheses are ppM wt. B(0.1), Al(0.8), Ga(0.06), P(0.2), F(0.1), Na(1.0), V(0.04), Mo(0.3), Ti(2.0), Zr(2.0), Mn(0.1), Ni(2.0), Zn(0.01), Cu(20.0), Cr(11.0), Fe(55.0). An excellent starting material for silicon solar cells is obtained on the basis of the low levels of B, Al, Ga, P and As. The source of the Fe and Cr is suspected to be the stainless steel container for liquid sodium. An independent check for the phosphorus content in Sample 2-19 was made by a wet colorimetric method and was found to be 90 parts per billion (ppB), in reasonable agreement with the SSMS result of 20 ppB. Silicon samples prepared from induction melted powder were evaluated for electrical properties using four-point probe conductivity and thermoelectric methods. The solid silicon in Sample 2-19 was found to be p-type and ranged in resistivity between 0.1 and 0.5 ohm cm. A stainless steel reactor was designed and fabricated to perform the SiF/sub 4/-Na reaction under P/sub SiF/sub 4// greater than 1 atmosphere. The amount of silicon produced was increased from 25 g per …
Date: December 1, 1977
Creator: Kapur, V.K.; Nanis, L. & Sanjurjo, A.
System: The UNT Digital Library
Thermal performance measurements on ultimate heat sinks--cooling ponds (open access)

Thermal performance measurements on ultimate heat sinks--cooling ponds

The primary objective of the studies described is to obtain the requisite data, with respect to modeling requirements, to characterize thermal performance of heat sinks for nuclear facilities existing at elevated water temperatures in result of experiencing a genuinely large heat load and responding to meteorological influence. The data should reflect thermal performance for combinations leading to worst-case meteorological influence. A geothermal water retention basin has been chosen as the site for the first measurement program and data have been obtained in the first of several experiments scheduled to be performed there. These data illustrate the thermal and water budgets during episodes of cooling from an initially high pond water bulk temperature. Monitoring proceeded while the pond experienced only meteorological and seepage influence. The data are discussed and are presented as a data volume which may be used for calculation purposes. Suggestions for future measurement programs are stated with the intent to maintain and improve relevance to nuclear ultimate heat sinks while continuing to examine the performance of the analog geothermal pond. It is further suggested that the geothermal pond, with some modification, may be a suitable site for spray pond measurements.
Date: December 1, 1977
Creator: Hadlock, R.K. & Abbey, O.B.
System: The UNT Digital Library
Bose-Einstein correlations in e/sup +/e/sup -/ collisions (open access)

Bose-Einstein correlations in e/sup +/e/sup -/ collisions

The MARK II detector is used to study the Bose-Einstein correlation between pairs and triplets of charged pions produced in hadronic decays of the J)psi), the ..sqrt..s = 4 to 7 GeV continuum above the J)psi), two photon events at ..sqrt..s = 29 GeV, and e/sup )plus/)e/sup )minus/) annihilation events at ..sqrt..s = 29 GeV as a function of Q/sup 2/, the four-momentum transfer squared. After corrections for Coulomb effects and pion misidentification, we find a nearly full Bose-Einstein enhancement ..cap alpha.. in the J)psi) and the two photon data and about half the maximum value in the other two data sets. The radius parameter )tau)(an average over space and time) given by pion pair analyses lies within a band of +-0.10 fm around 0.73 fm and is the same, within errors, for all four data sets. Pion triplet analyses also give a consistent radius of approx. 0.54 fm. fits to two-dimensional distributions R(q/sub T//sup 2/, q/sub C//sup 2/) of invariant components of Q/sup 2/ = q/sub T//sup 2/ )plus) q/sub C//sup 2/ give )tau)/sub T/ approx. )tau)C approx. )tau), where q/sub T/ is the transverse three-momentum difference calculated with respect to the net pair three-momentum, and q/sub C/ is …
Date: December 1, 1987
Creator: Juricic, I.
System: The UNT Digital Library
HTGR fuel recycle program. Quarterly progress report for the period ending November 30, 1977 (open access)

HTGR fuel recycle program. Quarterly progress report for the period ending November 30, 1977

The work reported includes the development of unit processes and equipment for reprocessing of High-Temperature Gas-Cooled Reactor (HTGR) fuel, the design and development of an integrated pilot line to demonstrate the head end of HTGR reprocessing using unirradiated fuel materials, and design work in support of Hot Engineering Tests (HET). Work is also described on trade-off studies concerning the required design of facilities and equipment for the large-scale recycle of HTGR fuels in order to guide the development activities for HTGR fuel recycle.
Date: December 1, 1977
Creator: unknown
System: The UNT Digital Library
Procedures and instructions for fabrication, assembly, and test of PCP III multisection ionization chamber (Q-2633) for reactor control (open access)

Procedures and instructions for fabrication, assembly, and test of PCP III multisection ionization chamber (Q-2633) for reactor control

This document is a collection of procedures for fabrication, assembly, and testing of a PCP III multisection ionization chamber (Q-2633) for reactor control.
Date: December 1, 1977
Creator: Chiles, M. M.; Clay, W. T. & Fowler, C. E.
System: The UNT Digital Library
Rockwell Hanford Operations' 1978 radiological improvement program (open access)

Rockwell Hanford Operations' 1978 radiological improvement program

This document describes the radiological improvement program (RIP) to be undertaken by Rockwell Hanford Operations during calendar year 1978. Actions taken in each facility to reduce exposure and to implement the Company's policy to conduct operations in a manner that assures radiation exposures to employees are maintained at the lowest levels reasonably achievable.
Date: December 30, 1977
Creator: Cunningham, D. S.
System: The UNT Digital Library
Stabilization of the axisymmetric instability in the PDX tokamak (open access)

Stabilization of the axisymmetric instability in the PDX tokamak

Passive stabilization, associated with the mutual inductances of the field shaping coils with the plasma and with each other, can stabilize the axisymmetric magnetohydrodynamic instability in the Princeton Poloidal Divertor Experiment device that was observed in earlier numerical studies.
Date: December 1, 1977
Creator: Jardin, S. C.
System: The UNT Digital Library
Safeguards Material Control and Accounting Program. Quarterly report, April-June 1980 (open access)

Safeguards Material Control and Accounting Program. Quarterly report, April-June 1980

This report summarizes the April-June 1980 activities of the Safeguards Material and Accounting Program sponsored by the US Nuclear Regulatory Commission (NRC) at the Lawrence Livermore National Laboratory. Progress is described on the application and further development of computer-based methodologies for assessing the vulnerabilities of MC and A systems in nuclear fuel-cycle facilities. The application effort involved an assessment of a scrap processing facility with the Structured Assessment Approach (SAA) methodology. The development effort concentrated on making the SAA more user-oriented. Work continued in providing technical analyses to assist the NRC in its development of the forthcoming MC and A upgrade rule. The technical analyses have involved value-impact studies on the draft MC and A upgrade rule using the LLNL Aggregrated Systems Model; specifically, progress has been made on the development of five MC and A performance measures. Other work has included the development of four protection principles for protecting MC and A data from falsification. We also describe progress in analyzing the actual and potential value of an NRC interfacility material accounting system for detecting data falsification.
Date: December 1, 1980
Creator: Poggio, A. J. & Dunn, D. R.
System: The UNT Digital Library
Assessment of tritium breeding requirements for fusion power reactors (open access)

Assessment of tritium breeding requirements for fusion power reactors

This report presents an assessment of tritium-breeding requirements for fusion power reactors. The analysis is based on an evaluation of time-dependent tritium inventories in the reactor system. The method presented can be applied to any fusion systems in operation on a steady-state mode as well as on a pulsed mode. As an example, the UWMAK-I design was analyzed and it has been found that the startup inventory requirement calculated by the present method significantly differs from those previously calculated. The effect of reactor-parameter changes on the required tritium breeding ratio is also analyzed for a variety of reactor operation scenarios.
Date: December 1, 1983
Creator: Jung, J.
System: The UNT Digital Library
Distribution of naphthalene between commercial resins and water--methanol solutions (open access)

Distribution of naphthalene between commercial resins and water--methanol solutions

Several XAD resins, two of their chemically modified derivatives, and two carbon absorbents were evaluated by measurement of distribution coefficients using the batch method. Numerical comparison of distribution data and graphical interpretation of these resins were also presented. The distribution differences were explained in terms of resin structure and solvent compositions. Naphthalene was the solute for the study, and methanol the solvent. It was found that Spherocarb, a newly developed carbon adsorbent, had very large distribution coefficient. However, in the application for separation, desorption can conceivably be a problem. Distribution data collected can be a valuable aid in the choice of adsorbent, solvent composition and other operating conditions in separation work.
Date: December 1, 1977
Creator: Chu, F.K.C.
System: The UNT Digital Library
UNLV Information Science Research Institute quarterly progress report (open access)

UNLV Information Science Research Institute quarterly progress report

This report presents research on information systems, information retrieval, and optical character recognition. (CBS)
Date: December 31, 1991
Creator: Nartker, T.A.
System: The UNT Digital Library
ORNL TNS program: microwave start-up of tokamak plasmas near electron cyclotron and upper hybrid resonances (open access)

ORNL TNS program: microwave start-up of tokamak plasmas near electron cyclotron and upper hybrid resonances

The scenario of toroidal plasma start-up with microwave initiation and heating near the electron cyclotron frequency is suggested and examined here. We assume microwave irradiation from the high field side and an anomalously large absorption of the extraordinary waves near the upper hybrid resonance. The dominant electron energy losses are assumed to be due to magnetic field curvature and parallel drifts, ionization of neutrals, cooling by ions, and radiation by low Z impurities. It is shown by particle and energy balance considerations that electron temperatures around 250 eV and densities of 10/sup 12/ to 10/sup 13/ cm/sup -3/ can be maintained, at least in a narrow region near the upper hybrid resonance, with modest microwave powers in the Impurity Study Experiment (ISX) (120 kW at 28 GHz) and The Next Step (TNS) (0.57 MW at 120 GHz). The loop voltages required for start-up from these initial plasmas are also estimated. It is shown that the loop voltage can be reduced by a factor of five to ten from that for unassisted start-up without an increase in the resistive loss in volt-seconds. If this reduction in loop voltage is verified in the ISX experiments, substantial savings in the cost of power …
Date: December 1, 1977
Creator: Peng, Y. K. M. & Borowski, S. K.
System: The UNT Digital Library
Bond-Strength Studies for 1-Mil-Diameter Gold Wires Bonded to Hybrid Microcircuit Substrates (open access)

Bond-Strength Studies for 1-Mil-Diameter Gold Wires Bonded to Hybrid Microcircuit Substrates

Detailed studies of the failure probability for gold wires bonded to multiplexer substrates under severe acceleration in the W79 artillery shell environments were made. The studies included: the calculated resultant pull forces exerted on the bond joints due to the W79 acceleration environments; the suitability of the loop-hook pull tests and the use of the normal Gaussian distribution theory for statistical description of bond strengths; and the probability of failure for gold wires bonded to multiplexer substrates under artillery shell accelerations using fixed angle pull tests and a Weilbull distribution theory for the statistical description. Preliminary statistical analyses of the bond strength data obtained from the conventional loop-hook pull tests for a multiplexer substrate HMC, have shown that the ball bond is strong enough to withstand the 0.17 gram design limit load due to the W79 gun barrel environments with a very low probability of failure. For the wedge bond, however, the results of a statistical analysis for the bond strength agree with experience which shows that the wedge bonds are generally much weaker than ball bonds in multiplexer substrates, and the probability of failure may be high enough to cause a problem. The degradation of the wedge bond strength …
Date: December 1, 1981
Creator: Kan, Y.R. & Prantil, V.C.
System: The UNT Digital Library
Kinetic analysis of dynamic PET data (open access)

Kinetic analysis of dynamic PET data

Our goal is to quantify regional physiological processes such as blood flow and metabolism by means of tracer kinetic modeling and positron emission tomography (PET). Compartmental models are one way of characterizing the behavior of tracers in physiological systems. This paper describes a general method of estimating compartmental model rate constants from measurements of the concentration of tracers in blood and tissue, taken at multiple time intervals. A computer program which applies the method is described, and examples are shown for simulated and actual data acquired from the Donner 280-Crystal Positron Tomograph.
Date: December 1, 1983
Creator: Knittel, B.
System: The UNT Digital Library
Evaluation of the /sup 232/Th neutron capture cross section above 3 keV (open access)

Evaluation of the /sup 232/Th neutron capture cross section above 3 keV

This memo describes an evaluation of the /sup 232/Th neutron capture cross section in the neutron energy range from 3 keV to 20 MeV. Most existing differential measurements are reviewed, and some data are renormalized to current values of the standards. Several experimentally determined sets of average resonance parameters are also discussed. From 3 to 50 keV the evaluated cross section is described by a set of average statistical resonance parameters. Above 50 keV the evaluated capture cross section is a smooth curve which follows the trend of the most recent measurements. The evaluated capture cross section is compared with many measurements and uncertainty estimates are given.
Date: December 1, 1977
Creator: de Saussure, G. & Macklin, R.L.
System: The UNT Digital Library
EBT-P gamma-ray shielding system (open access)

EBT-P gamma-ray shielding system

An elaborate study was carried out for the coil and biological shield of the ELMO Bumpy Torus proof-of-principle (EBT-P) device. A three-dimensional scoping study for the coil shield was performed for four different shielding options to define the heat load for each component and check the compliance with the design criterion of 10 watts maximum heat per coil from the gamma ray sources. Also, a detailed biological dose survey was performed which included: (a) the dose equivalent inside and outside the building, (b) the dose equivalent from the two mazes of the machine room, and (c) the skyshine contribution to the dose equivalent.
Date: December 1, 1981
Creator: Gohar, Y.
System: The UNT Digital Library
Heat Transfer With Laminar Flow in Concentric Annuli With Constant and Arbitrary Variable Axial Wall Temperature (open access)

Heat Transfer With Laminar Flow in Concentric Annuli With Constant and Arbitrary Variable Axial Wall Temperature

An analysis has been performed to determine the heat transfer characteristics for laminar forced-convection flow in a concentric annulus with prescribed surface temperatures. Three distinct problems were considered: (a) wall temperature prescribed at both the inside and outside wall; (b) inside wall temperature prescribed and the outside wall insulated; and (c) inside wall insulated and outside wall temperature prescribed. The solution for temperature distribution was similar to that obtained by Graetz for laminar heat convection in a pipe with uniform wall temperature. Expressions are presented for heat flux, mixing cup temperature, and Nusselt number as a function of downstream position. Eigenvalues and eigenfunctions were computed for values of the ratio of the inside to the outside radii for the boundary conditions. Mixing cup temperatures, local and fully developed Nusselt numbers, and thermal entry lengths are presented graphically. The solution of Problem (a) was extended to the situation in which the temperatures of the inside and outside walls of the annulus are not equal. By utilizing the method of superposition and the solutions already obtained for Problem (a), the temperature distributions were determined. By way of illustration, heat fluxes were calculated for several values of the temperature ratio (T/sub wi/-T/sub 0/)/(T …
Date: December 1, 1961
Creator: Viskanta, R.
System: The UNT Digital Library
FUELS, MATERIALS, COOLANT CHEMISTRY, AND FUEL HANDLING PROGRAMS. Quarterly Technical Progress Report, October--December 1971 (open access)
LMFBR safety program. Annual technical progress report. Government fiscal year, 1977 (open access)

LMFBR safety program. Annual technical progress report. Government fiscal year, 1977

Information is presented concerning the development of the SOMIX-1 computer code for sodium drop burning analysis; experimental analysis of burning sodium drops; aerosol leakage from containment buildings; high-temperature-concentration aerosols; aerosol source term from vaporized fuel; properties of high-temperature fuel mixtures; and development of the COMRADEX computer code for analysis of radiological doses in the environment from LMFBR accidents.
Date: December 15, 1977
Creator: unknown
System: The UNT Digital Library
Zircaloy-Clad UO2 Fuel Rod Evaluation Program. Quarterly Progress Report Nos. 6 and 7, February--July 1969 (open access)

Zircaloy-Clad UO2 Fuel Rod Evaluation Program. Quarterly Progress Report Nos. 6 and 7, February--July 1969

None
Date: December 31, 1969
Creator: Megerth, F. H.
System: The UNT Digital Library
Reactor containment analysis for BWR suppression systems. Progress report, April--October 1977 (open access)

Reactor containment analysis for BWR suppression systems. Progress report, April--October 1977

Work during the period included analytic studies of vent clearing and jet-slug dynamics and computer simulations (HEMP and CHAMP codes) of pressure suppression experiments.
Date: December 14, 1977
Creator: Edwards, L.L.
System: The UNT Digital Library
Revised Users Manual, Pulverized Coal Gasification or Combustion: 2-Dimensional (87-PCGC-2): Final Report, Volume 2. [87-PCGC-2] (open access)

Revised Users Manual, Pulverized Coal Gasification or Combustion: 2-Dimensional (87-PCGC-2): Final Report, Volume 2. [87-PCGC-2]

A two-dimensional, steady-state model for describing a variety of reactive and non-reactive flows, including pulverized coal combustion and gasification, is presented. Recent code revisions and additions are described. The model, referred to as 87-PCGC-2, is applicable to cylindrical axi-symmetric systems. Turbulence is accounted for in both the fluid mechanics equations and the combustion scheme. Radiation from gases, walls, and particles is taken into account using either a flux method or discrete ordinates method. The particle phase is modeled in a Lagrangian framework, such that mean paths of particle groups are followed. Several multi-step coal devolatilization schemes are included along with a heterogeneous reaction scheme that allows for both diffusion and chemical reaction. Major gas-phase reactions are modeled assuming local instantaneous equilibrium, and thus the reaction rates are limited by the turbulent rate mixing. A NO/sub x/ finite rate chemistry submodel is included which integrates chemical kinetics and the statistics of the turbulence. The gas phase is described by elliptic partial differential equations that are solved by an iterative line-by-line technique. Under-relaxation is used to achieve numerical stability. The generalized nature of the model allows for calculation of isothermal fluid mechanicsgaseous combustion, droplet combustion, particulate combustion and various mixtures of the …
Date: December 1, 1987
Creator: Smith, P. J.; Smoot, L. D. & Brewster, B. S.
System: The UNT Digital Library
DEVELOPMENT OF RING-JOINT FLANGES FOR USE IN THE HRE-2 (open access)

DEVELOPMENT OF RING-JOINT FLANGES FOR USE IN THE HRE-2

Ring-joint flanges were studied in thermal-cycle tests as part of the development work associated with Homogeneous Reactor Experiment No. 2 (HRE-2). The purpose of this study was to provide criteria for design, installation, and operation of joints that would remain leaktight under reactor operating temperatures and pressures. Joints ranging from 1/2 in., l500 lb to 4 in., 2500 lb and with various initial bolt loadings were cycled between room temperature and 636 deg F. It was demonstrated that when joints were made up to HRE-2 standards and specifications, leak rates of less than 0.25 x 10/sup -3/ g of water per day per inch of gasket pitch diameter could be routinely- attained. Undamaged gaskets could be reinstalled or new gaskets used with equal probability of achieving acceptable leak rates. The system installed in HRE-2 was provided with a high-pressure buffer system to ensure that the small amount of leakage to the cell would be nonradioactive. (auth)
Date: December 21, 1961
Creator: Robinson, J. N.; Lundin, M. I. & Spiewak, I.
System: The UNT Digital Library
A Summary of Industrial Accidents in USAEC Facilities (open access)

A Summary of Industrial Accidents in USAEC Facilities

The summary includes descriptions of serious accidents for l959 and 1960, AEC industrial injury frequency rates, criticality accidents, radiation exposures, accidents involving radioactive materials in AEC activities during 1959 and 1960, and accidents involving fatalities in AEC activities during l959 and 1960. (B.O.G.)
Date: December 1961
Creator: unknown
System: The UNT Digital Library