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Analytical model for a vertical buoyant jet

Description: An analytical model for a round and two-dimensional turbulent buoyant jet which is discharged vertically into a stagnant ambient is developed. The buoyant jet is considered to have three separate zone models which are matched to form a complete solution. The velocity field is determined for the entire jet and plume regions by the use of an eddy viscosity which varies along the axis of the jet. The centerline decay of buoyancy is determined throughout and the results are compared to existing num… more
Date: October 1, 1980
Creator: Lee, D. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High-temperature of thermodynamic properties of sodium

Description: The set of high-temperature thermodynamic properties for sodium in the two-phase and subcooled-liquid regions which was previously recommended, has been modified to incorporate recent experimental data. In particular, replacement of the previously estimated critical constants with experimentally-determined values has resulted in substantial differences in the region of the critical point. The following thermodynamic properties were determined: pressure, density, enthalpy, entropy, internal ener… more
Date: January 1, 1977
Creator: Padilla, A. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanical properties of LX-10-1. Process Development Endeavor No. 105

Description: Two Holston lots of LX-10-1 were evaluated for mechanical properties. The average 21/sup 0/C tensile failure stress-strain values for Lot 711-1 and 711-2 were 2.32 MPa at 0.15% and 2.07 MPa at 0.18%, respectively. The failure stress range for both lots was approximately 0.4 MPa at 74 C to 5.6 MPa at -37C. Several additional pressing cycles were required to obtain a density of 1.865 Mg/m/sup 3/ for Lot 711-1 material. The additional cycles appear to have increased the tensile failure stress of L… more
Date: October 1, 1977
Creator: Johnson, H.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Celotex trademark charring depths in the DT-18 shipping container

Description: Celotex {trademark}, the insulating material used between the outer and inner containers of the DT-18 shipping package, undergoes decomposition, combustion, or both when heated to temperatures exceeding 150{degrees}C. Several DT-18 packages that had previously undergone hypothetical thermal accident testing were opened and Celotex {trademark} charring depths ranging from {1/2} to 1 {1/2} in. were recorded. The majority of char depth data taken was between 3/4 and 1 {1/4} in. One-dimensional HEA… more
Date: March 1, 1992
Creator: Anderson, J.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multi-transducer dummy unit evaluation of polystyrene bead foam as an encapsulant for electronic packages

Description: A dummy electronic assembly without electronic components was used to measure loadings and deflections caused by 0.2, 0.3, 0.4, 0.5 and 0.6 g/cm/sup 3/ densities of polystyrene bead foam during fusion and thermal cycling. Previously developed and proven transducers showed that the lower three densities caused low and safe loads and deflections, but that the highest two densities must be used with care for fragile electronic components.
Date: September 1, 1980
Creator: Swanson, G. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Uncertainty in the power distribution for a fast reactor burnup cycle

Description: Demonstration that advanced reactor designs satisfy safety and performance goals requires the analysis of uncertainties in calculated reactor characteristics. Two of the important performance characteristics of advanced liquid metal reactors (LMR) are the burnup reactivity swing and the local power peaking factor. Previous work reported a study of the uncertainty in the burnup reactivity swing attributable to nuclear data uncertainties for a typical advanced LMR design. The results are reported… more
Date: January 1, 1989
Creator: Downar, D.J.; Khalil, H. (Purdue Univ., Lafayette, IN (USA) & Argonne National Lab., IL (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Detection sensitivity of x-ray CT imaging for NDE of green-state ceramics

Description: Improved ceramic-processing methods that use pressure slip-casting and injection molding are being developed at Norton Advanced Ceramics, with a goal of producing reliable structural ceramics for advanced heat engines. Nondestructive evaluation (NDE) of ceramic parts at different stages of processing can provide useful diagnostic information to help improve processing techniques. For example, an evaluation of density gradients in as-cast green-body samples can be used to judge mold performance … more
Date: 1991~
Creator: Gopalsami, N.; Rizo, P.; Ellingson, W. A. & Tracey, D. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Particulate behavior in a controlled-profile pulverized coal-fired reactor: A study of coupled turbulent particle dispersion and thermal radiation transport

Description: This report describes recent progress in a fundamental, three-year investigation of the coupled problem of turbulent particle dispersion and thermal radiation transport. The project's objective is to make measurements of particle size, velocity, number density, temperature and wall radiant heat flux in a parametrically-controlled reactor presently existent at Brigham Young University (BYU). Although the study proposed here is primarily designed to provide experimental data not currently availab… more
Date: January 1, 1992
Creator: Queiroz, M. & Webb, B.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Economic impact of using nonmetallic materials in low to intermediate temperature geothermal well construction

Description: Four appendices are included. The first covers applications of low-temperature geothermal energy including industrial processes, agricultural and related processes, district heating and cooling, and miscellaneous. The second discusses hydrogeologic factors affecting the design and construction of low-temperature geothermal wells: water quality, withdrawal rate, water depth, water temperature, basic well designs, and hydrogeologic provinces. In the third appendix, properties of metallic and nonm… more
Date: December 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quantitative nondestructive density determinations of very low-density carbon foams

Description: The carbon density and the carbon distribution in low-density foams that were manufactured by a modified salt-replica process were determined by bulk measurements of weight and volume and by x-ray computed tomography (CT). When determining the carbon density, both methods yielded similar results, however, the high spatial resolution of CT was found to yield nondestructive quantitative information on the carbon distribution that was not available from bulk measurements. The highest and lowest fo… more
Date: January 1, 1991
Creator: Moddeman, W. E.; Kramer, D. P.; Firsich, D. W.; Trainer, P. D.; Back, P. S.; Smith, S. D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Predicted temperature/time histories resulting from the burial of nuclear waste canisters in bedded salt

Description: This report provides computed thermal mappings for bedded salt surrounding canisters containing nuclear waste. This information can be used to study the possible migration of fluids within bedded salt under the influence of thermal gradients created by the heat-generating nuclear waste. The results presented were obtained from CINDA thermal models. Three different drift/canister configurations were modeled. The thermal conductivity of the salt was assumed to be temperature dependent while both … more
Date: July 1, 1980
Creator: George, O.L. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phase Transformations in Alumina. Technical Report, May to December 1961

Description: e transformation studies showed that synthetic aluminas produced in the laboratory were not transformed to alpha alumina at 400 to 700' deg n the presence of nitric acid and water vapor. Amorphous aluminn produced in the pilot plant was transformed to alpha alumina. This indicated that the amorphous alumina produced in the pilot plant is structurally predisposed to form alpha alumina. Most additives did not appear to have any special effects. Lithium formed zeta alumina, LiAl/sub 5/O/sub 8/. Ph… more
Date: December 1, 1961
Creator: Eding, H J; Huggins, M L & Brown, A G
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Freely expanding detonation products: Scaling of rate processes

Description: Using the Los Alamos reactive hydrodynamics code KIVA, calculations have been made to simulate the free expansion of cylinders of detonation products into a high vacuum. The emphasis of this paper is on the scaling of rate processes with cylinder size and initial conditions as a function of position in the expanding mass. The processes considered include diffusion, unimolecular decomposition, biomolecular radical reactions, and vibrational relaxation. The calculations also give time-dependent v… more
Date: January 1, 1988
Creator: Greiner, N. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characterization of Oil and Gas Reservoir Heterogeneity

Description: The ultimate objective of this cooperative research project is to characterize Alaskan petroleum reservoirs in terms of their reserves, physical and chemical properties, geologic configuration in relation to lithofacies and structure, and development potential. The project has two tasks: Task 1 is a geological description of the reservoirs including petrophysical properties, i.e., porosity, permeability, permeability variation, formation depth, temperature, and net pay, facies changes and reser… more
Date: January 1, 1992
Creator: Sharma, G. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characteristics of chars produced by pyrolysis following rapid heating of pulverized coal. [104 references]

Description: A 5.08-cm id pyrolysis furnace has been used to study pyrolysis following rapid heating of size graded pulverized coal particles as a function of isothermal pyrolysis time (0.018 to 1.025 second), particle size (50 to 181 ..mu..m), and parent coal (three lignites). The following experimental conditions were kept constant: Coal feed rate approximately equal to 0.5 g/min; volumetric flow rate of nitrogen temperature = 808/sup 0/C, and pressure = atmospheric. Under these conditions the heating rat… more
Date: February 1, 1977
Creator: Nsakala, N.; Walker, Jr., P. L. & Essenhigh, R. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Survey of Nonmetallic Liquid Coolants for Nuclear-Power Piles

Description: A comprehensive survey of the literature was made in an effort to identify nonmetallic materials of possible usefulness as liquid coolants. Materials having maximum melting points of 1000 deg F and boiling points of l200 deg F were considered, but boiling points above 2200 deg F were preferred. Melting points, boiling points, densities, heat capacities, and thermal conductivities were tabulated. Approximately 190 materials appeared to have melting and boiling temperatures in a suitable range. A… more
Date: May 26, 1950
Creator: Shaw, H.L. & Boulger, F.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electronic properties of silicon grain boundaries

Description: Polycrystalline silicon is a clean and relatively simple prototype of electronic ceramics. The theory of the electrostatic barriers which form at silicon grain boundaries will be discussed. The use of experimental conductance and capacitance measurements to obtain the barrier height and energy density of grain boundary states will be illustrated.
Date: January 1, 1980
Creator: Pike, G. E. & Seager, C. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Band structure and density of states of. beta. -silicon nitride

Description: The electronic energy band structure of ..beta..-Si/sub 3/N/sub 4/ has been calculated using the first principles LCAO method. The bottom of the Conduction Band (CB) is at GAMMA and the top of the valence band (VB) is located along GAMMAA line. The very flat top VB along GAMMAA accounts for a large hole effective mass. The indirect band gap obtained is very close to the experimental value of 5.2 eV. The density of states (DOS) and partial DOS are also obtained and are in good agreement with pho… more
Date: January 1, 1980
Creator: Ren, S.Y. & Ching, W.Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Errors in measuring level and density with purged dip tubes

Description: Measurement of liquid level and density and dip-tube sensors was evaluated by analysis and experiment. A model was developed to predict the characteristic error caused by the purge-gas bubble (dip-tube bias). Experimental results are presented to support these predictions and are also compared with data reported in the literature. It was shown that properly designed and calibrated dip tubes do not make significant contributions to the error in dip-tube level and density-measurement systems.
Date: November 1, 1977
Creator: Bradley, N.C.; Murray, W.P. & Googe, J.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Presupernova evolution of massive stars

Description: Population I stars of 15 M/sub mass/ and 25 M/sub mass/ have been evolved from the zero-age main sequence through iron core collapse utilizing a numerical model that incorporates both implicit hydrodynamics and a detailed treatment of nuclear reactions. The stars end their presupernova evolution as red supergiants with photospheric radii of 3.9 x 10/sup 13/ cm and 6.7 x 10/sup 13/ cm, respectively, and density structures similar to those invoked to explain Type II supernova light curves on a st… more
Date: December 15, 1977
Creator: Weaver, T. A.; Zimmerman, G. B. & Woosley, S. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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