Effects of lasering upon the electron gas and excited-state populations in xenon discharges.
Lasering effect on electron gas and excited state populations in xenon discharges
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Lasering effect on electron gas and excited state populations in xenon discharges
We demonstrate a minimally invasive nuclear magnetic resonance (NMR) technique that enables determination of the surface-area-to-volume ratio (S/V) of soft porous materials from measurements of the diffusive exchange of laser-polarized 129Xe between gas in the pore space and 129Xe dissolved in the solid phase. We apply this NMR technique to porous polymer samples and find approximate agreement with destructive stereological measurements of S/V obtained with optical confocal microscopy. Potential applications of laser-polarized xenon interphase exchange NMR include measurements of in vivo lung function in humans and characterization of gas chromatography columns.
Several biocompatible carrier agents, in which xenon is highly soluble and has a long T(1), were tested, and injected in living rats. These included saline, Intralipid suspension, perfluorocarbon emulsion and (129)Xe gas-filled liposomes. The T(1) of (129)Xe in these compounds ranged from 47 to 116 s. Vascular injection of these carrier agents was tolerated well, encouraging their use for further experiments in live animals. In vivo spectra, obtained from gas-filled liposomes and perfluorocarbon solutions, suggest that these carrier agents have potential for use in angiography and perfusion imaging. Copyright 2000 John Wiley & Sons, Ltd.
Sputter yields have been measured for polycrystalline diamond, single crystal diamond, a carbon-carbon composite, and molybdenum subject to bombardment with xenon. The tests were performed using a 3 cm Kaufman ion source to produce incident ions with energy in the range of 150 - 750 eV and profilometry based technique to measure the amount of sputtered material.
After having been in development for many years at Glenn Research Center, the NASA design 30 cm ring-cusp xenon ion engine was launched on the DS1 spacecraft on 24 October 1998 from the Kennedy Space Center in Florida.
A survey of low energy xenon ion impact sputter yields was conducted to provide a more coherent baseline set of sputter yield data and accompanying fits for electric propulsion integration. Data uncertainties are discussed and different available curve fit formulas are assessed for their general suitability. A Bayesian parameter fitting approach is used with a Markov chain Monte Carlo method to provide estimates for the fitting parameters while characterizing the uncertainties for the resulting yield curves.
Measurement of photoionization cross section between 400 to 600 angstroms for new autoionized energy levels in krypton, argon and xenon
Gas pressure and tube diameter effect on optical gain operating characteristics of xenon laser amplifier
Spectral energy distribution analyses for mercury- xenon arc, and carbon arc solar simulation tests on spacecraft
Xenon fluorides permit the controlled addition of fluorine across an olefinic double bond. They provide a series of fluorinating agents that permit ready separation from the product at a high purity. The reactions may be carried out in the vapor phase.
Xenon laser effect on interaction between electron gas and excited atoms in plasma
Current-voltage characteristics of xenon filled nuclear irradiated thermionic diodes
Electrical properties of xenon filled thermionic diodes in nuclear reactor radiation field
Excited xenon ion charge transfer efficiencies in Xe and oxygen, discussing Xe ion formation in electron impact monitoring
Helium and xenon electrical conductivity ratios approximations convergence in chemical equilibrium using Sonine polynomial
Spectral emission of xenon arc measured for IR absorption, noting relation of continuum spectral radiance to arc temperature and pressure
Microwave cavity fields perturbations by time varying xenon laser discharges
Excited states of xenon nuclei formed in beta decay of iodine and cesium isotopes