Effects of quenching and annealing on ionic conductivity in lithium fluoride
Quenching and annealing effects on ionic conductivity of lithium fluoride crystals
Lee, J. K.↗
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Nighttime ionic composition and temperature over Arecibo.
Ionic composition and temperature of nighttime topside ionosphere from analysis of incoherent backscatter spectra, discussing solar activity effects
Prasad, S. S.↗
Theoretical and experimental three-body ionic recombination coefficients.
Low density limit to three body ionic recombination coefficients in various gases
Flannery, M. R.↗
Ionic and biradical mechanisms in thermal and photo cis-trans isomerizations.
Ionic and biradical mechanisms in thermal and photo cis-trans isomerizations elucidated by planar and twisted configurations of polyenes
Evleth, E. M.↗
Radiative mean lives of some electronic states in beam-foil excited atomic and ionic carbon
Radiative mean lives and transition probabilities of electronic states in beam foil excited atomic and ionic carbon
Chupp, E. L.↗
Electrical screening procedure for solid ionic conductors
An electrical screening method has been developed for preliminary evaluation of polycrystalline specimens of candidates for use as solid ionic conductive electrolytes in batteries. The procedure measures dielectric loss and capacitance, from which are calculated an ac conductivity attributed provisionally to ions and an activation energy for that conductivity. Electronic conductivity is directly measured. The screening procedure applied to sodium beta-alumina yielded acceptable values for conductivity and activation energy.
Kautz, H. E.↗
Ionic migration and weathering in frozen Antarctic soils
Soils of continental Antarctica are forming in one of the most severe terrestrial environments. Continuously low temperatures and the scarcity of water in the liquid state result in the development of desert-type soils. In an earlier experiment to determine the degree to which radioactive Na(Cl-36) would migrate from a shallow point source in permafrost, movement was observed. To confirm this result, a similar experiment involving (Na-22)Cl was conducted. Significantly less movement of the Na-22 ion was observed. Ionic movement in the unfrozen interfacial films at mineral surfaces in frozen ground is held to be important in chemical weathering in Antarctic soils.
Ugolini, F. C.↗
Propagation through a slab of irregularities in a magneto-ionic medium.
A theory is developed to describe the propagation of characteristic waves through an infinite slab of irregularities in a magneto-ionic medium. The theory makes use of the asymptotic Green's dyadic. The results show that mode conversion is possible through scattering from irregularities in an anisotropic background. Some special cases are discussed and an example is given.
Simonich, D. M.↗
Research on the properties and interactions of simple atomic and ionic systems
Simple ionic systems were studied, such as metastable autoionizing states of the negative He ion, two-photon decay spectrum of metastable He ion, optical excitation with low energy ions, and lifetime measurements of singly ionized Li and metastable He ion. Simple atomic systems were also investigated. Metastable autoionizing atomic energy levels in alkali elements were included, along with lifetime measurements of Cr-53, group 2A isotopes, and alkali metal atoms using level crossing and optical double resonance spectroscopy.
Novick, R.↗
High pressure far infrared spectroscopy of ionic solids
A high-pressure far-infrared cell operating at up to truly hydrostatic pressures of 8 kbar is described and used to determine the anharmonic self-energies associated with the transverse optic modes of ionic solids in which q approximately equals zero. The cell allows far-infrared studies in the spectral range below 120 reciprocal cm. The transverse optic modes were investigated to determine their mode Gruneisen constants and the pressure dependence of their inverse lifetimes in RbI, CsI, and TlCl.
Lowndes, R. P.↗
Study of the extra-ionic electron distributions in semi-metallic structures by nuclear quadrupole resonance techniques
A straightforward self-consistent method was developed to estimate solid state electrostatic potentials, fields and field gradients in ionic solids. The method is a direct practical application of basic electrostatics to solid state and also helps in the understanding of the principles of crystal structure. The necessary mathematical equations, derived from first principles, were presented and the systematic computational procedure developed to arrive at the solid state electrostatic field gradients values was given.
Murty, A. N.↗
Latitudinal properties of the solar wind from studies of ionic comet tails
A statistical analysis is presented of the orientations of ionic comet tails in the solar wind. The analysis indicates that the radial solar wind speed is not necessarily higher near the solar poles than near the equator. The results refer to a long-term, global flow pattern and do not refer to short-term variations of solar wind speed.
Brandt, J. C.↗
Satellite measurements of ionic concentrations applied to low altitude incoherent scatter interpretations
The determination of ion and electron temperatures and electron density from incoherent scatter radar data has in the past involved assumptions concerning the ionospheric composition below 250 km. Using a very large data base of measurements of O(+), O2(+), NO(+), and N2(+) made by the Atmosphere Explorer C satellite, a model has been developed of the ionic concentration between 130 and 300 km as a function of solar zenith angle. As the effect of the new model is to increase the radar determinations of the temperature, this may explain previous discrepancies between Langmuir probe and incoherent scatter temperatures, where the comparisons have been made at these low altitudes
Torr, M. R.↗
Review of rate coefficients of ionic reactions determined from measurements made by the atmosphere explorer satellites
The large data base of aeronomic parameters measured by the Atmosphere Explorer C, D, and E satellites since December 1973 has been used to determine a number of reaction rate coefficients highly relevant to our understanding of thermospheric chemistry. In this paper the results are reviewed for ionic rate coefficients for recombination of NO(+), O2(+), for reactions of O(+) + N2, N2(+) + O, and O(++) + O, and for various reactions involving O(+)(2D) and O(+)(2P) ions with O and N2.
Torr, D. G.↗
About the influence of electron temperature and relative ionic composition on ion depletion in the wake of the AE-C satellite
Data from the cylindrical electrostatic probe and from the Bennett ion mass spectrometer on board the AE-C satellite were examined in order to determine the influence of electron temperature (Te) and ion composition on the amount of ion depletion in the wake of an ionospheric satellite. It is observed that both electron temperature and ionic composition significantly influence the amount of ion depletion in the near wake zone, as measured by the ion current collected by the cylindrical probe mounted about 32 cm from the surface of the satellite. The ion current in the wake in an O(+) dominated plasma decreases with respect to ambient by about two orders of magnitude at a Te of about 1000 K and by a factor of about 30 at a Te of about 3000 K. For a plasma where the O(+) density equals the H(+) density, the ion current decreases by a factor of 6 in the wake at a Te of about 1000 K and by a factor of 2.3 at 3000 K.
Samir, U.↗
Ionic bond effects on the mean excitation energy for stopping power
Molecular mean excitation energies for ionic bonded molecules calculated according to the local plasma approximation are compared to the Bragg rule. Adjustments of 15% are calculated for LiF in agreement with experiments while 6% adjustments are predicted for HF and 3% for LiH.
Wilson, J. W.↗
Ionic charge state distribution of helium, carbon, oxygen, and iron in an energetic storm particle enhancement
An analysis is presented of the ionic charge state distribution of He, C, O and Fe in the energetic storm particle event of September 28-29, 1978. Data were obtained with the ULEZEQ electrostatic analyzer-proportional counter on board the ISEE 3 spacecraft. The He(+)/He(++) ratio between 0.4 and 1 MeV/n is shown to be significantly lower during the energetic storm particle event than during the preceding period of solar flare particle enhancement, with a temporal evolution similar to that of the Fe/He ratio as reported by Klecker et al. (1981). Increases in the mean charge state for oxygen by about 3% and for iron by about 16% are also noted. The temporal variations in charge states are accounted for in terms of first-order Fermi acceleration of the pre-existing solar flare particles by a propagating interplanetary shock wave.
Hovestadt, D.↗
Ionic composition of the earth's radiation belts
Several different ion species have been positively identified in the earth's radiation belts. Besides protons, there are substantial fluxes of helium, carbon and oxygen ions, and there are measurable quantities of even heavier ions. European, American and Soviet space experimenters have reported ion composition measurements over wide ranges of energies: at tens of keV (ring-current energies) and below, and at hundreds of keV and above. There is still a gap in the energy coverage from several tens to several hundreds of keV where little observational data are available. In this review emphasis is placed on the radiation belt ionic structure above 100 keV. Both quiet time conditions and geomagnetic storm periods are considered, and comparison of the available space observations is made with theoretical analysis of geomagnetically trapped ion spatial, energy and charge state distributions.
Spjeldvik, W. N.↗