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Analysis of Paraho oil shale products and effluents: an example of the multi-technique approach

Description: Inorganic analysis of solid, liquid and gaseous samples from the Paraho Semiworks Retort was completed using a multitechnique approach. The data were statistically analyzed to determine both the precision of each method and to see how closely the various techniques compared. The data were also used to determine the redistribution of 31 trace and major elements in the various effluents, including the offgas for the Paraho Retort operating in the direct mode. The computed mass balances show that … more
Date: June 10, 1979
Creator: Fruchter, J. S.; Wilkerson, C. L.; Evans, J. C. & Sanders, R. W.
Partner: UNT Libraries Government Documents Department
open access

Analytical model for the dynamic resistivity of electrically-exploded conductors

Description: A detailed model for the dynamic resistivity of an exploding conductor presents many difficulties. An electrically-exploded conductor undergoes significant hydrodynamic expansion as it is heated. Resistivity is a function of both the temperature and density of a conductor and realistic models for resistivity over the range of parameter space experienced by an exploding conductor are quite complex. See for example, the model of Lee and More (1984). Calculation of the hydrodynamic expansion of th… more
Date: October 10, 1986
Creator: Lee, R. S.
Partner: UNT Libraries Government Documents Department
open access

Time series analysis of reactor thermocouple data. [LMFBR]

Description: Time-series analysis techniques are applied to nuclear reactor thermocouple data to investigate coolant temperatures measured within the fueled test assembly. The coolant temperature distribution within a fuel assembly affects the length of time a fuel assembly may be operated in a power reactor and, therefore, is an important economic consideration in the design of reactor fuel systems. Frequency-domain signal conditioning techniques were used to reveal the smoothly varying thermocouple signal… more
Date: April 10, 1980
Creator: Devary, J.L.
Partner: UNT Libraries Government Documents Department
open access

Benchmark field study of deep neutron penetration

Description: A unique benchmark neutron field has been established at the Lawrence Livermore National Laboratory (LLNL) to study deep penetration neutron transport. At LLNL, a tandem accelerator is used to generate a monoenergetic neutron source that permits investigation of deep neutron penetration under conditions that are virtually ideal to model, namely the transport of mono-energetic neutrons through a single material in a simple geometry. General features of the Lawrence Tandem (LATAN) benchmark field… more
Date: June 10, 1991
Creator: Morgan, J. F.; Sale, K. (Lawrence Livermore National Lab., CA (USA) ); Gold, R.; Roberts, J. H. & Preston, C. C. (Metrology Control Corp., Richland, WA (USA) )
Partner: UNT Libraries Government Documents Department
open access

Electron energies in metals

Description: The modern era of electron-electron interactions began a decade ago. Plummer's group initiated a program of using angular resolved photoemission to examine the band structure of the simple metals. Beginning with aluminum, and carrying on to sodium and potassium, they always found that the occupied energy bands were much narrower than expected. For example, the compressed energy bands for metallic potassium suggest a band effective mass of m* = 1.33m{sub e}. This should be compared to the band m… more
Date: July 10, 1991
Creator: Mahan, G.D. (Oak Ridge National Lab., TN (United States) Tennessee Univ., Knoxville, TN (United States). Dept. of Physics and Astronomy)
Partner: UNT Libraries Government Documents Department
open access

Scaling of current density, total current, emittance, and brightness for hydrogen negative ion sources

Description: The atomic and molecular processes that play a principal role in negative ion formation in a hydrogen negative ion discharge are discussed. The collisions of energetic electrons with gas molecules within the discharge lead to vibrationally excited molecules. Thermal electrons in turn attach to these excited molecules and generate negative ions via the dissociative attachment process. A system geometry chosen to optimize these collision processes is discussed that consists of a high-power discha… more
Date: July 10, 1986
Creator: Hiskes, J.R.
Partner: UNT Libraries Government Documents Department
open access

Transposable elements and genetic instabilities in crop plants

Description: Transposable elements have long been associated with certain unstable loci in maize and have been intensively studied by McClintock and others. It is known that a transposable element can control the expression of the structural genes at the locus where it resides. These controlling elements in maize are now beginning to be studied at the molecular level. Using recombinant molecular probes we have been able to describe the changes induced by the controlling element Ds at the shrunken locus. Ds … more
Date: April 10, 1981
Creator: Burr, B. & Burr, F.
Partner: UNT Libraries Government Documents Department
open access

Investigation into the repetition-rate limitations of magnetic switches

Description: The use of magnetic switches to generate high power pulses has opened up a whole new spectrum of possibilities. Here we describe an investigation into the maximum repetition rates possible with these devices.
Date: February 10, 1982
Creator: Birx, D. L.; Reginato, L. L. & Schmidt, J. A.
Partner: UNT Libraries Government Documents Department
open access

Energy generation in convective shells of low mass, low metallicity stars

Description: We report on the non-negligible energy generation from the {sup 13}C neutron source and neutron capture reactions in low mass, low metallicity AGB stars. About 10{sup 4} L{sub {circle dot}} are generated within the thermal pulse convective shell by the combination of the {sup 13}C({alpha}, n){sup 16}O rate and the sum of the Y(Z,A)(n,{gamma})Y(Z,A + 1) reactions and beta decays. The inclusion of this energy source in an AGB thermal pulse evolution is shown to alter the evolution of the convecti… more
Date: November 10, 1989
Creator: Bazan, G. (Illinois Univ., Urbana, IL (USA). Dept. of Astronomy) & Lattanzio, J.C. (Lawrence Livermore National Lab., CA (USA))
Partner: UNT Libraries Government Documents Department
open access

Remote servicing features of two new mirror fusion reactors

Description: Some general approaches to remote blanket change and servicing operations are briefly outlined for the LLL Field Reversed Mirror and Tandem Mirror Fusion reactors. Remote servicing system design requirements are briefly discussed. (RME)
Date: June 10, 1977
Creator: Neef, W.S.
Partner: UNT Libraries Government Documents Department
open access

Longitudinal spin fluctuations in nickel

Description: The longitudinal and transverse spin fluctuations in Ni have been measured below {Tc} by means of polarized neutron scattering in the momentum range 0.06 < q < 0.18 {angstrom}{sup -1}. In transverse scans spin wave peaks at E{sub q} = Dq{sup 2} appear as expected from early measurements performed with unpolarized neutrons. The longitudinal magnetic scattering {sub {chi}L}(q, E), on the other hand, is quasielastic without any signature of inelastic peaks near E{sub q}. The q and T dependences of… more
Date: October 10, 1989
Creator: Boeni, P.; Martinez, J. L. & Tranquada, J. M.
Partner: UNT Libraries Government Documents Department
open access

Understanding and accepting fusion as an alternative energy source

Description: Fusion, the process that powers our sun, has long promised to be a virtually inexhaustible source of energy for mankind. No other alternative energy source holds such bright promise, and none has ever presentd such formidable scientific and engineering challenges. Serious research efforts have continued for over 30 years in an attempt to harness and control fusion here on earth. Scientists have made considerable progress in the last decade toward achieving the conditions required for fusion pow… more
Date: December 10, 1987
Creator: Goerz, D.A.
Partner: UNT Libraries Government Documents Department
open access

Characterization of cell suspensions from solid tumors

Description: The desirable features of cells in suspension will necessarily be dependent upon the use for which the cells were prepared. Adequate cell yield or recovery is defined by the measurement to be performed. Retention of cellular morphology is important for microscopic identification of cell types in a heterogenous cell suspension, and may be used to determine whether the cells in suspension are representative of those in the tumor in situ. Different dispersal protocols may yield cells with differen… more
Date: July 10, 1985
Creator: Pallavicini, M.
Partner: UNT Libraries Government Documents Department
open access

Nuclear power high technology colloquium: proceedings

Description: Reports presenting information on technology advancements in the nuclear industry and nuclear power plant functions have been abstracted and are available on the energy data base.
Date: December 10, 1984
Partner: UNT Libraries Government Documents Department
open access

Giant resonance phenomena in the electron impact ionization of heavy atoms and ions

Description: Heavy atoms and ions offer an interesting opportunity to study atomic physics in a region where the atomic structure is dominated by the interelectronic interactions. One illustration of this is the profound term dependence of atomic orbitals for certain configurations of heavy atoms and ions. The appearance of giant scattering resonances in the cross sections for ionization of heavy atoms by electron impact is a manifestation of resonance behavior. Such resonant structures arise from the doubl… more
Date: June 10, 1986
Creator: Younger, S.M.
Partner: UNT Libraries Government Documents Department
open access

Use of single-cutter data in the analysis of PDC bit designs

Description: A method is developed for predicting cutter forces, temperatures, and wear on PDC bits as well as integrated bit performance parameters such as weight-on-bit (WOB), drilling torque, and bit imbalance. A computer code called PDCWEAR has been developed to make this method available as a tool for general bit design. The method uses single-cutter data to provide a measure of rock drillability and employs theoretical considerations to account for interaction among closely spaced cutters on the bit. … more
Date: October 10, 1986
Creator: Glowka, D.A.
Partner: UNT Libraries Government Documents Department
open access

Doppler-shifted resonance absorption by hot electrons

Description: When the large Doppler shifts of hot-electron-ring ECRH absorption are taken into account, the spatial location of the bulk of the energy absorption can be significantly shifted from the cold-plasma resonance region. The high parallel velocity electrons absorb most of the wave energy, thereby shielding the bulk of the electron distribution from the heating source. A simple one-dimensional model of this process has been formulated, based on a right-hand circularly polarized wave which is inciden… more
Date: November 10, 1981
Creator: Shearer, J.W.
Partner: UNT Libraries Government Documents Department
open access

Chasing the x sub f dependence of J/. Psi. production

Description: We discuss the combined effects of hard scattering processes and intrinsic heavy-quark components in the hadron wavefunction on the x{sub f} dependence of J/{psi} production. The A dependence arises from nuclear absorption, comover interactions, shadowing of parton distributions, and intrinsic heavy quarks. 9 refs., 1 fig.
Date: June 10, 1991
Creator: Vogt, R.
Partner: UNT Libraries Government Documents Department
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