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I. The preparation and reactivity of active uranium. II. Computer programming, and electrochemistry and EPR interfacing. III. The design and construction of a gas chromatograph temperature programmer
Abstract
Very finely divided uranium and thorium metal powders have been prepared by reduction of UCl$\sb4$ and ThCl$\sb4$ in an argon atmosphere. These metals show exceptional chemical reactivity and have been used in a large variety of different types of chemical reactions. The oxophilicity of these active metals is so great that they react with the ethereal solvents ethylene glycol dimethyl ether (DME) and tetrahydrofuran, even at low temperatures. Active Uranium (prepared in DME) is an extremely active butadiene polymerization catalyst. Surface analyses of Active Uranium powders (prepared in DME) by ESCA, Auger, and SAM have been conducted. A method has been developed to prepare these highly reactive metal powders in hydrocarbon solvents via the hydrocarbon soluble reducing agent ((TMEDA)Li) $\sb2$ (Naphthalene) (TMEDA = N,N,N$\sp\prime$,N$\sp\prime$-Tetramethylethylenediamine). Large quantities of this complex can be made inexpensively and conveniently by sonicating Li, naphthalene, and TMEDA in toluene. A C-H bond in TMEDA is activated by active uranium to give a metal hydride which can be used for a variety of hydrogenation reactions. Active uranium can be used to reductively couple aromatic ketones to give either alkenes or alkanes. The stepwise reduction of alpha-diketones or acyloins has been shown to give alkynes, alkenes, and ultimately alkanes. Active uranium prepared in hydrocarbon solvents can be used for the polymerization or oligomerization of trans-stilbene and diphenylacetylene. Computer software has been written to interface many laboratory instruments to a Nicolet 1280 laboratory minicomputer. A Bruker ER-200 Electron Paramagnetic Resonance Spectrometer, as well as a variety of electrochemical equipment has been interfaced. A temperature programmer for gas chromatographs has been designed and constructed. This temperature programmer will work on any gas chromatograph which has a phase-controlled oven heater.
Subject Area
Chemistry|Computer science
Recommended Citation
Kahn, Bruce Edward, "I. The preparation and reactivity of active uranium. II. Computer programming, and electrochemistry and EPR interfacing. III. The design and construction of a gas chromatograph temperature programmer" (1987). ETD collection for University of Nebraska-Lincoln. AAI8806144.
https://digitalcommons.unl.edu/dissertations/AAI8806144