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Alkyl, hydride, and related bis(trimethylsilyl)-amide derivatines of the 4f- and 5f-block metals (open access)

Alkyl, hydride, and related bis(trimethylsilyl)-amide derivatines of the 4f- and 5f-block metals

Physical properties (magnetic susceptibility, NMR, crystal structure, etc.) are reviewed for trivalent lanthanide/actinide derivatives, divalent lanthanide derivatives, and tetravalent actinide derivatives. (DLC)
Date: December 1, 1979
Creator: Andersen, R. A.
System: The UNT Digital Library
Time projection spectrometer (open access)

Time projection spectrometer

The time projection chamber (TPC) is discussed. Its advantage is its ability to collect a great deal of information on multiparticle reactions from high-energy colliding beam experiments. The TPC makes it possible to reconstruct all the charged particles in the reaction, and it can be used for mass identification. (FS)
Date: December 1, 1979
Creator: Anderson, H.L.
System: The UNT Digital Library
Ion implantation and laser annealing of high T/sub c/ superconducting materials (open access)

Ion implantation and laser annealing of high T/sub c/ superconducting materials

The materials investigated consisted of thin films of Nb-Ge, V-Si, Nb-N, Nb-C-N and Nb-Ir prepared by evaporation, sputtering or CVD onto substrates of alumina, sapphire or polycrystalline Hastelloy B. Single crystals of Nb/sub 3/Ir, NbN, V/sub 3/Si and V/sub 3/Ge were also studied and some laser annealing results will be presented. Laser annealing was performed in air using a Q-switched, (15 x 10/sup -9/ sec duration), Ruby laser with energy densities ranging from 0.1 to 10 J/cm/sup 2/. Single, sometimes overlapping, pulses were used. The texture, microstructure and phase composition of the films were examined by x-ray diffraction. Ion scattering and nuclear reaction analysis were used to determine stoichiometries versus depth in the films. Near-surface melting was monitored from ion scattering measurements of the depth profiles of an ion implanted marker species before and after laser annealing. Surface topography was monitored with optical microscopy and SEM. Ion channeling analysis was utilized to determine lattice defect configurations and damage effects to the single crystal samples. These various analyses were correlated to measurements of superconducting transition temperatures, T/sub c/, before and after laser annealing.
Date: December 1, 1979
Creator: Appleton, B. R.; White, C. W.; Stritzker, B.; Meyer, O.; Gavaler, J. R.; Braginski, A. I. et al.
System: The UNT Digital Library
Effect of Grinding on the Stucture of Glassy Carbon (open access)

Effect of Grinding on the Stucture of Glassy Carbon

An earlier suggestion that various allotropic forms of carbon preexist as micron size crystallites in glassy carbon was investigated. Samples previously heated only to 1000 C and thinned by crushing (grinding) or by ion melting and observed using transmission electron diffraction and microscopy gave single crystal or spotty ring patterns for the former but only diffuse rings for the latter. Wide range X-ray diffraction, small angle X-ray scattering, density and surface area measurements of as received plate and ground material show that grinding flattens the internal pore structure of the material, decreasing the specific surface area by 25 percent and increasing the radius of gyration by about 8 percent, It is concluded that the spot patterns indicating crystalline forms result from strain relief during grinding.
Date: December 1, 1979
Creator: Baker, D. F.; Bragg, R. H. & Rao, A. S.
System: The UNT Digital Library
Status of tandem mirror theory (open access)

Status of tandem mirror theory

This report contains the text and slides used for the review talk on tandem mirror theory presented at the meeting of the Division of Plasma Physics, A.P.S., Boston, MA, November 12-16, 1979. Topics covered include classical confinement, equilibria, MHD- and micro-stability, radial transport, and thermal barriers.
Date: December 12, 1979
Creator: Baldwin, D.E.
System: The UNT Digital Library
Structure of High Angle Grain Boundaries in Metals and Ceramic Oxides (open access)

Structure of High Angle Grain Boundaries in Metals and Ceramic Oxides

A critical review is given of the state of our current knowledge of the structure of high angle grain boundaries in metals and in ceramic oxides. Particular attention is given to effects due to differences in the bonding and crystal structure in these solid types. The results of recent experimental work and efforts to model grain boundary structure using computer simulation methods are described. Important characteristic features of boundaries in these materials are discussed. Difficulties which are presently being encountered in efforts to determine their structure are pointed out.
Date: December 1, 1979
Creator: Balluffi, R.W.; Bristowe, P.D. & Sun, C.P.
System: The UNT Digital Library
Synthesis and characterization of Pa(IV), Np(IV), and Pu(IV) borohydrides (open access)

Synthesis and characterization of Pa(IV), Np(IV), and Pu(IV) borohydrides

The actinide borohydrides of Pa, Np, and Pu have been prepared and some of their physical and optical properties measured. X-ray powder diffraction photographs of Pa(BH/sub 4/)/sub 4/ have shown that it is isostructural to Th(BH/sub 4/)/sub 4/ and U(BH/sub 4/)/sub 4/. Np(BH/sub 4/)/sub 4/ and Pu(BH/sub 4/)/sub 4/ are much more volatile than the borohydrides of Th, Pa, and U and are liquids at room temperature. Results from low-temperature single-crystal x-ray diffraction investigation of Np(BH/sub 4/)/sub 4/ show that its structure is very similar to Zr(BH/sub 4/)/sub 4/. With the data from low-temperature infrared and Raman spectra, a normal coordinate analysis on Np(BH/sub 4/)/sub 4/ and Np(BD/sub 4/)/sub 4/ has been completed. EPR experiments on Np(BH/sub 4/)/sub 4//Zr(BH/sub 4/)/sub 4/ and Np(BD/sub 4/)/sub 4//Zr(BD/sub 4/)/sub 4/ have characterized the ground electronic state. 5 figures.
Date: December 1, 1979
Creator: Banks, R.H. & Edelstein, N.M.
System: The UNT Digital Library
Effect of Grain Size on the Acoustic Emission Generated During Plastic Deformation of Aluminum (open access)

Effect of Grain Size on the Acoustic Emission Generated During Plastic Deformation of Aluminum

Acoustic emission signals from polycrystalline Al 1100 samples during plastic deformation were analyzed with respect to the strain rate and grain size. A kinematic model is proposed to account for the observed behavior. An experimental acoustic emission parameter, equivalent to the average energy of the acoustic events, correlates satisfactorily with the computed energy of moving dislocations during the deformation process. Both energies attain a maximum value for a certain grain size, and are directly dependent on the strain rate.
Date: December 1, 1979
Creator: Baram, J. & Rosen, M.
System: The UNT Digital Library
Proceedings of the atmospheric tracers and tracer application workshop (open access)

Proceedings of the atmospheric tracers and tracer application workshop

In addition to presentations by participating members a general discussion was held in order to summarize and outline the goals and objectives of the workshop. A number of new low level background tracers such as heavy methanes, perfluorocarbons, multiply labeled isotopes such as /sup 13/C/sup 18/O/sub 2/, helium 3, in addition to sample collection techniques and analytical methods for various tracers were discussed. This report is a summary of discussions and papers presented at this workshop.
Date: December 1, 1979
Creator: Barr, S. & Gedayloo, T. (comps.)
System: The UNT Digital Library
Program for personnel protection from oxygen deficiency in a Fast Breeder Reactor Test Facility (FFTF) (open access)

Program for personnel protection from oxygen deficiency in a Fast Breeder Reactor Test Facility (FFTF)

The FFTF reactor is described. Procedures and equipment used to protect personnel from potential hazards of oxygen deficient environments are described.
Date: December 12, 1979
Creator: Bell, J.C.
System: The UNT Digital Library
FFTF auxiliary system testing program: results and overview (posters) (open access)

FFTF auxiliary system testing program: results and overview (posters)

The most important aspects of the Auxiliary System Testing Program to the overall startup of FFTF were in the areas of integrated testing of inerted cells, integrated leak rate testing of the containment building and testing of the waste gas processing systems for effluent cover gas and effluent cell atmosphere gases. The basic test methods and test results for these areas of the FFTF startup program are presented.
Date: December 1, 1979
Creator: Bliss, R. J. & Hunter, J. R.
System: The UNT Digital Library
Thermal aspects of waste emplacement in layered tuffs (open access)

Thermal aspects of waste emplacement in layered tuffs

The thermal response of layered tuffs in Yucca Mountain at NTS to radwaste emplacement at 711 m depth (Bullfrog tuff) was analyzed. Three in-situ boiling criteria were examined. No boiling is predicted for any burial depth with power densities up to 150 kW/acre. Allowable powerdensities are plotted vs depth below 711 m for both HLW and spent fuels. (DLC)
Date: December 31, 1979
Creator: Bulmer, B.M. & Lappin, A.R.
System: The UNT Digital Library
Design and operating experience of EBR-II intermediate heat exchanger (open access)

Design and operating experience of EBR-II intermediate heat exchanger

Experimental Breeder Reactor II (EBR-II) has operated for over 15 years at the Idaho National Engineering Laboratory near Idaho Falls. EBR-II has served the nation in providing information on fuels, materials, and components under conditions approaching those expected for commercial power plants. In addition, EBR-II is a power plant generating electricity with an availability of about 70%. A key component, the Intermediate Heat Exchanger (IHX), of any Liquid Metal Fast Breeder Reactor (LMFBR) must perform with a high degree of reliability for successful commercialization. The design and operating experience gained from EBR-II demonstrates that the IHX can be built and operated with confidence that its performance and reliability will be satisfactory.
Date: December 1979
Creator: Buschman, H. W.; Koenig, J. F. & Stone, C. C.
System: The UNT Digital Library
DETERMINATION OF CARBON IN ATMOSPHERIC AEROSOLS BY DEUTERON-INDUCED NUCLEAR REACTIONS (open access)

DETERMINATION OF CARBON IN ATMOSPHERIC AEROSOLS BY DEUTERON-INDUCED NUCLEAR REACTIONS

Nuclear reactions induced by 7.6-MeV deuterons are used to determine total carbon in atmospheric aerosols. The {sup 12}C(d,n){sup 13}N reaction produces the radionuclide {sup 13}N, a 10.0-min positron emitter, which is detected by its 0.511-MeV annihilation radiation. The detection system is a Ge(Li) {gamma}-ray spectrometer. The method is nondestructive of the sample, permitting the sample to be studied by additional methods. Comparison of carbon found by deuteron activation analysis with that found by independent but destructive combustion methods shows a standard deviation of 10% for 15 samples analyzed over a wide range of carbon contents. The detection limit is estimated to be 0.5 {micro}g/cm{sup 2}, corresponding to a carbon concentration of 0.2% in a sample of total thickness 250 {micro}g/cm{sup 2}.
Date: December 1, 1979
Creator: Clemenson, Mark; Novakov, Tihomir & Markowitz, Samuel S.
System: The UNT Digital Library
Wind characteristics for design of wind turbines: research in the USA (open access)

Wind characteristics for design of wind turbines: research in the USA

The Pacific Northwest Laboratory (PNL) of the United States Department of Energy has the primary responsibility for providing information on wind characteristics for design and for evaluation of performance of wind energy conversion systems (WECS). The objectives of the whole program are, broadly, to develop technical wind information which is relevant to the design of WECS, to determine suitable methods of measuring and analyzing the wind for evaluating WECS performance, and to communicate the information usefully to WECS designers.
Date: December 1, 1979
Creator: Connell, J.R.
System: The UNT Digital Library
Search for direct photon production at Fermilab energies and comparison with direct photon measurements at ISR energies (open access)

Search for direct photon production at Fermilab energies and comparison with direct photon measurements at ISR energies

A search for direct photon production has been performed at Fermilab in 200 and 300 GeV/c proton-Be interactions over a wide range of X/sub F/ and P/sub perpendicular to/. An excess of photons has been detected which when interpreted as single photon production yields a ..gamma../..pi../sup 0/ ratio which averages .070 +- .025 in the region 1.5 < p/sub perpendicular to/ < 4.0 GeV/c and -.7 < X/sub F/ < .0. This measurement is discussed and a comparison of this result with the ISR measurements of the ..gamma../..pi../sup 0/ ratio has been made in an attempt to infer the energy dependence of direct photon production.
Date: December 1, 1979
Creator: Cox, B.
System: The UNT Digital Library
Seismic transient analysis of a containment vessel with penetrations. [HVAC valves] (open access)

Seismic transient analysis of a containment vessel with penetrations. [HVAC valves]

A linear transient analysis of the FFTF containment vessel was conducted with STAGS to justify the load levels used for the seismic qualification testing of the heating and ventiliation valve operators. The modeling consists of a thin axisymmetric shell for the containment vessel with four penetrations characterized by linear and rotational inertias as well as attachment characteristics to the shell. Motions considered are horizontal, rocking and vertical input to the base, and the solution is carried out by direct integration. Results show that the test levels and the approximate analyses considered are conservative. Response spectra for some containment vessel penetrations applicable to the model are presented.
Date: December 1, 1979
Creator: Dahlke, H. J. & Weiner, E. O.
System: The UNT Digital Library
APPLICATION OF THE IMAGINARY TIME STEP METHOD TO THE SOLUTION OF THE STATIC HARTREE-FOCK PROBLEM (open access)

APPLICATION OF THE IMAGINARY TIME STEP METHOD TO THE SOLUTION OF THE STATIC HARTREE-FOCK PROBLEM

A method of solution of the static Hartree-Fock problem is proposed. The method, based upon the extension of the method of solution of the time-dependent Hartree-Fock problem to imaginary time, promises to be more efficient, and applicable to more complex systems than previously proposed numerical methods.
Date: December 1, 1979
Creator: Davies, K.T.R.; Flocard, H.; Krieger, S.; Weiss, M.S.; Flocard, H.; Krieger, S. et al.
System: The UNT Digital Library
New developments in gamma-ray continuum spectroscopy (open access)

New developments in gamma-ray continuum spectroscopy

Much information on states of high spin (30 to 60h-bar) comes from ..gamma..-ray spectroscopy of their numerous de-excitation cascades. In such studies selection of particular (high) spin regions are made through use of multiplicity filters and total-energy spectrometers. The nuclei investigated so far, whether initially near-spherical or deformed, all appear to become deformed rotors at high spin, and effective moments of inertia can be obtained. A new technique of determining energy correlations among coincident transitions in the cascade offers great promise for the future. 9 figures.
Date: December 1, 1979
Creator: Diamond, R. M.
System: The UNT Digital Library
Wind direction variations in strong winds (open access)

Wind direction variations in strong winds

Significant differences exist between the angular fluctuations experienced at a fixed point, averaged over a disk of rotation, and those felt by a blade element rotating about a horizontal axis. The static and dynamic descriptions of these fluctuations are an important aspect in design considerations and in the development of tracking strategies. Several methods of description and interpretation have been presented here, but further development is clearly required for a comprehensive picture of wind direction fluctuations.
Date: December 1, 1979
Creator: Doran, J. C.
System: The UNT Digital Library
Meteorological and topographical indicators of wind energy for regional assessments (open access)

Meteorological and topographical indicators of wind energy for regional assessments

Techniques using meteorological and topographical indicators of wind energy, developed by PNL and applied to the Northwest wind resource assessment, improved the reliability of the analysis of the geographical distribution of wind energy. The identification and application of these indicators led to an improved understanding of the conditions associated with high and low wind energy. Furthermore, these indicators are especially useful in complex terrain and wind-data-sparse areas for obtaining a somewhat realistic estimate of the wind energy resource.
Date: December 1, 1979
Creator: Elliott, D. L.
System: The UNT Digital Library
LARGE CORRECTIONS TO HIGH p{sub T} HADRON-HADRON SCATTERING IN QCD (open access)

LARGE CORRECTIONS TO HIGH p{sub T} HADRON-HADRON SCATTERING IN QCD

We have eomputed the first non-trivial QCD corrections to the quark-quark scattering process which contributes to the production of hadrons at large p{sub T} in hadron-hadron collisions. Using quark distribution functions defined in deep inelastic scattering and fragmentation functions defined in one particle inclusive e{sup +}e{sup -} annihilation, we find that the corrections are large. This implies that QCD perturbation theory may not be reliable for large p{sub T} hadron physics.
Date: December 1, 1979
Creator: Ellis, R. K.; Furman, M. A.; Haber, H. E. & Hinchliffe, I.
System: The UNT Digital Library
Parameters affecting radionuclide migration in geologic media (open access)

Parameters affecting radionuclide migration in geologic media

Adsorption of several nuclides (Sr, Tc, Cs, Ba, Ce, Eu) on tuff, monzonite, and argillite was studied experimentally. 3 tables. (DLC)
Date: December 31, 1979
Creator: Erdal, B.R.; Bayhurst, B.P. & Daniels, W.R.
System: The UNT Digital Library
Structural and microstructural design in brittle materials (open access)

Structural and microstructural design in brittle materials

Structural design with brittle materials requires that the stress level in the component correspond to a material survival probability that exceeds the minimum survival probability permitted in that application. This can be achieved by developing failure models that fully account for the probability of fracture from defects within the material (including considerations of fracture statistics, fracture mechanics and stress analysis) coupled with non-destructive techniques that determine the size of the large extreme of critical defects. Approaches for obtaining the requisite information are described. The results provide implications for the microstructural design of failure resistant brittle materials by reducing the size of deleterious defects and enhancing the fracture toughness.
Date: December 1, 1979
Creator: Evans, A.G.
System: The UNT Digital Library