Search Results

Advanced search parameters have been applied.
open access

ANHARMONIC POTENTIAL CONSTANTS AND THEIR DEPENDENCE UPON BOND LENGTH

Description: Empirical study of cubic and quartic vibrational force constants for diatomic molecules shows them to be approximately exponential functions of internuclear distance. A family of curves is obtained, determined by the location of the bonded atoms in rows of the periodic table. Displacements between successive curves correspond closely to those in Badger's rule for quadratic force constants (for which the parameters are redetermined to accord with all data now available). Constants for excited el… more
Date: August 1, 1961
Creator: Herschbach, D.R. & Laurie, V.W.
Partner: UNT Libraries Government Documents Department
open access

Impulsive ion acceleration in earth's outer magnetosphere

Description: Considerable observational evidence is found that ions are accelerated to high energies in the outer magnetosphere during geomagnetic disturbances. The acceleration often appears to be quite impulsive causing temporally brief (10's of seconds), very intense bursts of ions in the distant plasma sheet as well as in the near-tail region. These ion bursts extend in energy from 10's of keV to over 1 MeV and are closely associated with substorm expansive phase onsets. Although the very energetic ions… more
Date: January 1, 1985
Creator: Baker, D.N. & Belian, R.D.
Partner: UNT Libraries Government Documents Department
open access

Relativistic effects in the atomic and nuclear few-body problems

Description: Relativistic effects in the atomic and nuclear few-body systems are classified and discussed with the emphasis on electromagnetic transitions. The size of relativistic corrections, calculational techniques and ambiguities, and comparison of theory and experiment are considered. 8 figures.
Date: January 1, 1980
Creator: Friar, J.L.
Partner: UNT Libraries Government Documents Department
open access

Applications of induction linac technology to heavy ion fusion

Description: Evaluation of the application of heavy ion accelerators to ignite d-t pellets in a thermonuclear reactor is discussed. Accelerator design requirements considered include transport-limited current, beam injection conditions, and pulse bunching and focusing characteristics. The desirability of resonant and non-resonant accelerating structures is comparatively examined. The required power system switch tubes are discussed. It is concluded that heavy ion accelerators could offer a promising solutio… more
Date: July 1, 1977
Creator: Faltens, A. & Keefe, D.
Partner: UNT Libraries Government Documents Department
open access

Damage nucleation in Si during ion irradiation

Description: Damage nucleation in single crystals of silicon during ion irradiation is investigated. Experimental results and mechanisms for damage nucleation during both room and liquid nitrogen temperature irradiation with different mass ions are discussed. It is shown that the accumulation of damage during room temperature irradiation depends on the rate of implantation. These dose rate effects are found to decrease in magnitude as the mass of the ions is increased. The significance of dose rate effects … more
Date: January 1, 1984
Creator: Holland, O.W.; Fathy, D. & Narayan, J.
Partner: UNT Libraries Government Documents Department
open access

Alignment and orientation in ion/endash/atom collisions

Description: Recent progress in the theoretical study of alignment and orientation in atom-atom and ion-atom collisions at intermediate energies is reviewed. Recent systematic studies of the alignment and orientation of electronic charge cloud distributions of excited states resulting from such collisions clearly have provided more detailed information about the underlying collision dynamics. However, since accurate determination of these parameters is quite difficult, both theoretically and experimentally,… more
Date: January 1, 1987
Creator: Kimura, M. & Lane, N.F.
Partner: UNT Libraries Government Documents Department
open access

Acceleration of beam ions during major radius compression in TFTR

Description: Tangentially co-injected deuterium beam ions were accelerated from 82 keV up to 150 keV during a major radius compression experiment in TFTR. The ion energy spectra and the variation in fusion yield were in good agreement with Fokker-Planck code simulations. In addition, the plasma rotation velocity was observed to rise during compression.
Date: September 1, 1985
Creator: Wong, K. L.; Bitter, M.; Hammett, G. W.; Heidbrink, W.; Hendel, H.; Kaita, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Calorimetric and optical beam diagnostics on the LBL 120-keV neutral beam test facility

Description: The 120-keV Neutral Beam Test Facility at LBL is fitted with several types of instrumentation to determine the properties of the 10- to 15-A hydrogen and deuterium beams produced in this facility. These include a neutral particle dump for measuring the temperature profile generated by the beam, and a fixed and a moveable ion dump to measure the temperature profiles generated by the various ion components after they have been swept out of the neutral beam by a bending magnet. These several dumps… more
Date: October 1, 1977
Creator: Burrell, C. F.; Cooper, W. S.; Steele, W. F. & Smith, R. R.
Partner: UNT Libraries Government Documents Department
open access

Emission in the 50-80 A region from highly ionized silver in PLT tokamak plasmas

Description: The spectrum of silver emitted by Princeton Large Torus (PLT) tokamak plasmas has been recorded in the 25 to 150 A region by a multichannel time-resolving grazing-incidence spectrometer. Silver atoms have been introduced in the tokamak plasma using the laser blow-off technique. For the first time, lines emitted within the 3p-3d transitions of Ag XXIX, Ag XXX, and Ag XXXI ions, between 50 and 80 A, have been identified.
Date: September 1, 1985
Creator: Schwob, J.L.; Wouters, A.; Suckewer, S.; Cohen, S.A. & Finkenthal, M.
Partner: UNT Libraries Government Documents Department
open access

Modeling studies on the precipitation of Kr after implantation into metals

Description: A rate-theory approach is applied to interpreting observations on the precipitation of Kr injected into Ni at temperatures between 25 and 560/degree/C. At temperatures of 400/degree/C or higher, the implanted Kr precipitates evolve into a bi-modal size distribution containing small solid precipitates and an additional population of larger, faceted bubbles. The calculations explore the dependence of the observed bi-modal distribution on the maximum size of the solid Kr precipitates and the effec… more
Date: February 1, 1988
Creator: Rest, J.
Partner: UNT Libraries Government Documents Department
open access

D/sup -/ production by multiple charge-transfer collisions of low-energy D ions and atoms in cesium vapor

Description: The production of D/sup -/ by multiple charge-transfer collisions of a D/sup +/ beam in a cesium-vapor target is considered for D/sup +/ energies above 300 eV. The cross sections relevant to D/sup -/ formation are obtained by a least-squares fit of three-charge-state differential equations to experimental yield curves. Implications for production of intense negative-ion beams are discussed, and speculations are made about extrapolation to lower engeries.
Date: January 22, 1978
Creator: Hooper, E. B. Jr.; Willmann, P. A. & Schlachter, A. S.
Partner: UNT Libraries Government Documents Department
open access

Neutron scattering from solutions: the hydration of lanthanide and actinide ions

Description: The neutron scattering difference method is described and applied to investigations of the aqua rare-earth ions, Nd/sup 3 +/ and Dy/sup 3 +/. Metal-water distances and hydration numbers have been unambiguously determined for these ions' inner coordination spheres. The values of the hydration number, n, of 8.5 +- 0.2 for Nd/sup 3 +/ and 7.4 +- 0.5 for Dy/sup 3 +/, directly support the claim of Spedding et al. that n decreases by one unit across the lanthanide series. The possible application of … more
Date: January 1, 1985
Creator: Hahn, R.L.; Narten, A.H. & Annis, B.K.
Partner: UNT Libraries Government Documents Department
open access

Efficiencies of gas neutralizers for multi-MeV beams of light negative ions

Description: Measurements are reported of the neutral and charged particle fractions produced by running beams of Li/sup -/, C/sup -/, O/sup -/, and Si/sup -/ at energies up to 7 MeV through gas cells of N/sub 2/, Ar, or CO/sub 2/. We discuss the implications of these measurements for the design of neutralizers to produce high energy light atom beams for heating or current drive in tokamaks.
Date: November 1, 1981
Creator: Grisham, L. R.; Post, D. E.; Johnson, B. M.; Jones, K. W.; Barette, J.; Kruse, T. H. et al.
Partner: UNT Libraries Government Documents Department
open access

General multi-configuration Hartree--Fock program: MCHF77. [In FORTRAN (double precision) for IBM 360 and 370]

Description: This technical report contains a listing of a general program for multi-configuration Hartree--Fock (MCHF) calculations, including its documentation. Several examples are given showing how the program may be used. Typical output for several cases is also presented. This program has been tested over an extended period of time for a large variety of cases. This program is written for the IBM 360 or 370 in double-precision arithmetic.
Date: November 1, 1977
Creator: Fischer, C F
Partner: UNT Libraries Government Documents Department
open access

Dependence of secondary ion emission from organic material on the energy loss of the impacting heavy ion

Description: Samples of the amino acid valine were irradiated by 2.5 MeV-Ar, 0.8 MeV-Kr and 1.0 MeV Xe beams from the Argonne Dynamitron accelerator in order to study the energy distributions of ejected secondary ions. For Kr and Xe the nuclear stopping power exceeded the electronic stopping power by a factor 2 or 3, respectively, but the functional shape of the energy distributions and the mean ejection energies (0.9--1.4 eV) indicated that the molecular ions (M{plus minus}H){sup {plus minus}} are desorbed… more
Date: January 1, 1991
Creator: Hunt, J.E. (Argonne National Lab., IL (United States)) & Wien, K. (Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik)
Partner: UNT Libraries Government Documents Department
open access

Recent US target-physics-related research in heavy-ion inertial fusion: simulations for tamped targets and for disk experiments in accelerator test facilities

Description: Within the last few years, there have also appeared in the Heavy-Ion Fusion literature several studies of targets which have outer tampers. One-dimensional simulations indicate higher target gains with a judicious amount of tamping. But for these targets, a full investigation has not been carried through in regards to conservative criteria for fluid instabilities as well as reasonable imperfections in target fabrication and illumination symmetry which all affect target ignition and burn. Compar… more
Date: June 24, 1982
Creator: Mark, J.W.K.
Partner: UNT Libraries Government Documents Department
open access

Emission Characteristics of Tantalum, Tungsten, Rhenium, and Iridium in Plasma Diodes

Description: Experimental determinations of the ionic and electronic emission characteristics of Ta, W, Re, and lr cathodes in vapor thermionic converters are compared. It is shown that Ta provides superior thermal ionization qualities at high pressure compared with W, Re, and Lr. High electronic current densities may be obtained from Cs on Re and Cs on Ir at much lower Cs vapor pressures than from Ta or W. An over-all efficiency of 19% was achieved with a Re cathode at 2440 deg K. (auth)
Date: March 15, 1962
Creator: Gust, W. H.
Partner: UNT Libraries Government Documents Department
open access

Collisionally excited few-electron systems: theoretical introduction and survey. [2-200 keV]

Description: We consider excitation, ionization, and charge transfer in collisions of protons (and antiprotons) with the single-electron targets H, He/sup +/, and Li/sup 2 +/. These collisions are first compared to other types of ion-atom collisions. A brief review of our own theoretical method is given; in particular we describe how we allow for both large charge transfer and ionization probabilities while retaining the computational efficiency that allows us to consider a variety of collision partners and… more
Date: January 1, 1982
Creator: Ford, A.L.; Reading, J.F. & Becker, R.L.
Partner: UNT Libraries Government Documents Department
open access

Conversion rates in power plant plumes based on filter pack data. Part I. Coal-fired Cumberland plume

Description: The TVA Cumberland Steam Plant plume was monitored during the August 1978 Tennessee Plume Study of Project STATE. Samples were obtained by employing a triple screen high-volume assembly which contained: (1) a quartz filter for collecting particulate SO/sub 4//sup 2 -/, NO/sub 3//sup -/ and NH/sub 4//sup +/, (2) two NaCl-impregnated cellulose filters for collecting gaseous nitrate, and (3) two K/sub 2/CO/sub 3/-impregnated cellulose filters for collecting SO/sub 2/. Formation rates of sulfate an… more
Date: January 1, 1980
Creator: Forrest, J; Garber, R W & Newman, L
Partner: UNT Libraries Government Documents Department
open access

Anion-exchange resin-based desulfurization process

Description: Under DOE Grant No. FG22-90PC90309, the University of Tennessee Space Institute (UTSI) is contracted to further develop its anion-exchange, resin-based desulfurization concept to desulfurize alkali metal sulfates. From environmental as well as economic viewpoints, it is necessary to remove soluble sulfates from the wastes created by flue gas desulfurization systems. In order to do this economically, a low-cost desulfurization process for spent sorbents is necessary. UTSI's anion-exchange resin-… more
Date: January 1, 1992
Creator: Sheth, A.C.; Strevel, S.D. & Dharmapurikar, R.
Partner: UNT Libraries Government Documents Department
open access

Capillary liquid chromatography using laser-based and mass spectrometric detection

Description: The research performed during the past year has mainly focused on investigating and minimizing the problems listed below that limit the practical utility of these capillary electrokinetic separation techniques in chemical analysis. (1) Analyses are hindered by poor reproducibility. This is largely a result of complicated and irreproducible capillary wall-solute interactions that often result in adsorption and mobility changes. (2) While the Micellar Electrokinetic Capillary Chromatography techn… more
Date: January 1, 1991
Creator: Sepaniak, M.J. & Cook, K.D.
Partner: UNT Libraries Government Documents Department
open access

Cationically polymerizable monomers derived from renewable sources

Description: The objective of this project is to make use of products obtained from renewable plant sources as monomers for the direct production of polymers which can be used for a wide range of plastic applications. In this report is described progress in the synthesis and polymerization of cationically polymerizable monomers and oligomers derived from botanical oils, terpenes, natural rubber, and lignin. Nine different botanical oils were obtained from various sources, characterized and then epoxidized. … more
Date: October 1, 1991
Creator: Crivello, J. V.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen