University Research Institute for Analytical Chemistry P.O.Box 666,Hadley,MA 01035-0666

<正>The University Research Institute for Analytical Chemistry(URIAC),the research and laboratory division of ICP Information Newsletter,Inc.,located in Amherst near the University of Massachusetts,provides consulting,chemical research,analysis, testing,and training and is the home of analytical experts performing non-routine,specialty chemical analyses for academic labo-     

High pressure since P. W. Bridgman - A personal view

Abstract

In this paper an attempt is made to review high pressure research over the past three or four decades from a personal viewpoint. Focus is first on two technical developments; the introduction of shock wave techniques in solids, and the extension of the static pressure range by a factor of 20–30.

The major emphasis is on the introduction of high pressure into the mainstream of modern science through the concept that pressure is a powerful, indeed an essential tool in understanding molecular and electronic properties of matter. These properties are classified under the headings (q) structure (x-rays) (b) molecular dynamics (c) pressure tuning spectroscopy (d) chemical and electronic rate phenomena (e) chemical synthesis.     

Etude R.P.E. des anions paramagnétiques SnH4 - et SiF4 -

The E.S.R. spectra of the radicals SnH₄ ^- and SiF₄ ^- are described, and their spectral parameters compared with those of PH₄ and PF₄ respectively.     

Elements of Mechanics,by P.F. Kelly

Applications of optogalvanic spectroscopy developed since the resurgence of interest in optogalvanic detection are reviewed. The optogalvanic effect is a change in the electrical properties of a discharge caused by illuminating the discharge with radiation having a wavelength corresponding to an atomic or molecular transition in the discharge. The general scheme of optogalvanic spectroscopy is presented, followed by a discussion of the gas discharge physics of the optogalvanic effect. Applications of optogalvanic detection in moderate resolution spectroscopy, in Doppler-free spectroscopy, and in analytic studies are discussed.