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

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

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 approximately 1% or greater fractions of the As, Co, Hg, N, Ni, S and Se are released during retorting and redistributed to the product shale oil, retort water or product offgas. The fraction for these seven elements ranged from almost 1% for Co and Ni to 50 to 60% for Hg and N. Approximately 20% of the S and 5% of the As and Se are released. The mass balance redistribution during retorting for Al, Fe, Mg, V and Zn was observed to be no greater than .05%. These redistribution figures are generally in agreement with previous mass balance studies made for a limited number of elements on laboratory or smaller scale pilot retorts. 7 tables.
Date: June 10, 1979
Creator: Fruchter, J. S.; Wilkerson, C. L.; Evans, J. C. & Sanders, R. W.
System: The UNT Digital Library
Proceedings of the symposium on experiments using enriched antiproton, polarized proton, and polarized antiproton beams at Fermilab energies (open access)

Proceedings of the symposium on experiments using enriched antiproton, polarized proton, and polarized antiproton beams at Fermilab energies

The conference included 10 papers, one of which appeared previously under conference number Conf: 770675-1. Separate abstracts were prepared for the remaining nine papers. (JFP)
Date: June 10, 1977
Creator: Yokosawa, A. (ed.)
System: The UNT Digital Library
Analytical model for the dynamic resistivity of electrically-exploded conductors (open access)

Analytical model for the dynamic resistivity of electrically-exploded conductors

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 the conductor during and subsequent to the explosion is likewise dependent on detailed knowledge of the equation of state for the conductor in a range where few experimental data exist. A further complication is the strong magnetic field which couples the hydrodynamic expansion to the currents flowing in the expanding material. In spite of the difficulties, progress is being made on detailed modeling of fuses and exploding conductors (Lidemuth and co-workers, 1985). A simpler approach has proved to be quite useful for modeling the electrical behavior of exploding bridgewire and slapper detonators and for modeling the explosionss of large conductors exploded with large capacitor banks. In the work described here, a simple, empirical model was developed which can be expressed as a closed-form algebraic expression involving four …
Date: October 10, 1986
Creator: Lee, R. S.
System: The UNT Digital Library
Time series analysis of reactor thermocouple data. [LMFBR] (open access)

Time series analysis of reactor thermocouple data. [LMFBR]

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 signals from the noisy digital data. Examination of the cross-correlation function for thermocouple pairs suggested an alternate surging and ebbing of coolant flow within certain zones of the fuel assembly. These zones corresponded to thermocouples which experienced higher or lower than predicted coolant temperatures. This time series analysis contributed greatly toward the understanding of fuel assembly thermal hydraulics.
Date: April 10, 1980
Creator: Devary, J.L.
System: The UNT Digital Library
Microearthquakes in geothermal prospecting (open access)

Microearthquakes in geothermal prospecting

None
Date: December 10, 1974
Creator: Lange, A.L.
System: The UNT Digital Library
Benchmark field study of deep neutron penetration (open access)

Benchmark field study of deep neutron penetration

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 are described with emphasis on neutron source characteristics and room return background. The single material chosen for the first benchmark, LATAN-1, is a steel representative of Light Water Reactor (LWR) Pressure Vessels (PV). Also included is a brief description of the Little Boy replica, a critical reactor assembly designed to mimic the radiation doses from the atomic bomb dropped on Hiroshima, and its us in neutron spectrometry. 18 refs.
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) )
System: The UNT Digital Library
The Structures of NiZr$sub 2$, NiZr and Their Hafnium Analogs (open access)

The Structures of NiZr$sub 2$, NiZr and Their Hafnium Analogs

None
Date: March 10, 1962
Creator: Kikpatrick, M. E.; Bailey, D. M. & Smith, J. F.
System: The UNT Digital Library
Electron energies in metals (open access)

Electron energies in metals

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 mass found from optical conductivity m*/m{sub e} = 1.01 {plus minus} 0.01. The discrepancy between these results is startling. It was this great difference which started my group doing calculations. Our program was two-fold. On one hand, we reanalyzed the experimental data, in order to see if Plummer's result was an experimental artifact. On the other hand, we completely redid the electron-electron self-energy calculations for simple metals, using the most modern choices of local-field corrections and vertex corrections. Our results will be reported in these lectures. They can be summarized as following: Our calculations give the same effective masses as the older calculations, so the theory is relatively unchanged; Our analysis of the experiments suggests that the recent measurements of band narrowing …
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)
System: The UNT Digital Library
Scaling of current density, total current, emittance, and brightness for hydrogen negative ion sources (open access)

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

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 discharge in tandem with a low electron temperature bath, the two regions separated by a magnetic filter. The current density extracted from such a system is found to scale inversely with the system scale length provided the gas density and electron density are also increased inversely with scale length. If a system is scaled downward in size to provide a new beamlet but one with increased current density, and these beamlets are packed to fill the original dimension, the new total extracted current will exceed the original total current by the scale factor. The emittance, epsilon, of the new system remains unchanged. The brightness, J/epsilon/sup 2/, of the new system will also be increased in proportion to the scale factor. 4 refs., 2 figs.
Date: July 10, 1986
Creator: Hiskes, J.R.
System: The UNT Digital Library
Transposable elements and genetic instabilities in crop plants (open access)

Transposable elements and genetic instabilities in crop plants

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 elements appear to be large and dissimilar insertions into the wild-type locus - two elements actually map within the transcribed region of the gene. Genetic instabilities have been described in other economically important plants but the bases for these phenomena have not been understood. We believe that it is likely that some of these instabilities are the result of transposable element activity much as in the case of maize.
Date: April 10, 1981
Creator: Burr, B. & Burr, F.
System: The UNT Digital Library
Investigation into the repetition-rate limitations of magnetic switches (open access)

Investigation into the repetition-rate limitations of magnetic switches

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.
System: The UNT Digital Library
Energy generation in convective shells of low mass, low metallicity stars (open access)

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

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 convective shell boundaries, and, hence, how the {sup 13}C is ingested into the convective shell. Also, the duration of the pulse itself is reduced by the additional energy input. The nucleosynthetic consequences are discussed for these evolutionary changes. 17 refs., 5 figs.
Date: November 10, 1989
Creator: Bazan, G. (Illinois Univ., Urbana, IL (USA). Dept. of Astronomy) & Lattanzio, J.C. (Lawrence Livermore National Lab., CA (USA))
System: The UNT Digital Library
Remote servicing features of two new mirror fusion reactors (open access)

Remote servicing features of two new mirror fusion reactors

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.
System: The UNT Digital Library
Longitudinal spin fluctuations in nickel (open access)

Longitudinal spin fluctuations in nickel

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 {sub {chi}L}(q, E) resemble the paramagnetic scattering above {Tc}, i.e., the linewidth is roughly proportional to q{sup 2.5} and the integrated intensity I(q) is proportional to (q{sup 2} + {kappa}{sub z}{sup 2}){sup -1}. 8 refs., 3 figs.
Date: October 10, 1989
Creator: Boeni, P.; Martinez, J. L. & Tranquada, J. M.
System: The UNT Digital Library
O(N) real-space method for ab initio quantum transport calculations: Application to carbon nanotube - metal contacts (open access)

O(N) real-space method for ab initio quantum transport calculations: Application to carbon nanotube - metal contacts

Article on O(N) real-space method for ab initio quantum transport calculations and application to carbon nanotube-metal contacts.
Date: December 10, 2001
Creator: Buongiorno Nardelli, Marco; Fattebert, Jean-luc & Bernholc, Jerry
System: The UNT Digital Library
Spontaneous polarization and piezoelectricity in boron nitride nanotubes (open access)

Spontaneous polarization and piezoelectricity in boron nitride nanotubes

Article on spontaneous polarization and piezoelectricity in boron nitride nanotubes.
Date: June 10, 2003
Creator: Nakhmanson, Serge M.; Calzolari, Arrigo; Meunier, Vincent; Bernholc, Jerry & Buongiorno Nardelli, Marco
System: The UNT Digital Library
Understanding and accepting fusion as an alternative energy source (open access)

Understanding and accepting fusion as an alternative energy source

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 power, and recent experimental results and technological progress have made the scientific feasibility of fusion a virtual certainty. With this knowledge and confidence, the emphasis can now shift toward developing power plants that are practical and economical. Although the necessary technology is not in hand today, the extension to an energy producing system in 20 years is just as attainable as was putting a man on the moon. In the next few decades, the world's population will likely double while the demand for energy will nearly quadruple. Realistic projections show that within the next generation a significant fraction of our electric power must come from alternative energy sources. Increasing environmental concerns may further accelerate this timetable in which new energy sources must be introduced. …
Date: December 10, 1987
Creator: Goerz, D.A.
System: The UNT Digital Library
Characterization of cell suspensions from solid tumors (open access)

Characterization of cell suspensions from solid tumors

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 different degrees of clonogenicity, as well as altered biochemical features, such as loss of cellular proteins, surface antigens, nucleotide pools, etc. The quality of the cell suspension can be judged by the degree of cell clumping and level of cellular debris, both of which impact on flow cytometric measurements and studies in which the number of cells be known accurately. Finally, if the data measured on the cells in suspension are to be extrapolated to phenomena occurring in the tumor in situ, it is desirable that the cells in suspension are representative of those in the solid tumor in vivo. This report compares characteristics of tumor cell suspensions obtained by different types of selected disaggregation methods. 33 refs., 2 figs., 4 tabs.
Date: July 10, 1985
Creator: Pallavicini, M.
System: The UNT Digital Library
Nuclear power high technology colloquium: proceedings (open access)

Nuclear power high technology colloquium: proceedings

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
Creator: unknown
System: The UNT Digital Library
Giant resonance phenomena in the electron impact ionization of heavy atoms and ions (open access)

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

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 double well nature of the scattering potential and have recently been identified in the cross sections for the electron impact ionization of several xenon-like ions. The results of calculations showing effects for a variety of other ions are summarized. 7 refs., 4 figs.
Date: June 10, 1986
Creator: Younger, S.M.
System: The UNT Digital Library
Use of single-cutter data in the analysis of PDC bit designs (open access)

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

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. Experimental data are presented to establish the effects of cutter size and wearflat area on the forces that develop during rock cutting. Waterjet assistance is shown to significantly reduce cutting forces, thereby extending bit life and reducing WOB and torque requirements in hard rock. The effects of bit profile, cutter placement density, bit rotary speed, and wear mode on bit life and drilling performance are investigated. 21 refs., 34 figs., 4 tabs.
Date: October 10, 1986
Creator: Glowka, D.A.
System: The UNT Digital Library
Doppler-shifted resonance absorption by hot electrons (open access)

Doppler-shifted resonance absorption by hot electrons

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 incident from the high-field side in the parallel direction. In this model, less than 1% of the electrons absorb more than 90% of the wave energy for the case of 30-keV maximum parallel electron energy, 28-GHz microwaves, and a 1-m magnetic field scale length. The effect should be included in power balance models and Fokker-Planck velocity distribution calculations. The Doppler shift also appears for a variety of ray-tracing code calculations in the MFTF-B thermal barrier region.
Date: November 10, 1981
Creator: Shearer, J.W.
System: The UNT Digital Library
Chasing the x sub f dependence of J/. Psi. production (open access)

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

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.
System: The UNT Digital Library
Future impact of the experimental results from the Argonne ZGS (open access)

Future impact of the experimental results from the Argonne ZGS

Experimental programs at Argonne ZGS are reviewed with emphasis on experiments using polarized beams.
Date: January 10, 1980
Creator: Yokosawa, A.
System: The UNT Digital Library