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111.
Sonochemical treatment of natural ground water at different high frequencies: preliminary results 总被引:5,自引:0,他引:5
Naturally occurring ground water polluted by highly volatile chlorinated compounds, with 1,2-dichloroethane as the main contaminant, was sonicated with high frequency ultrasound (361, 620 and 1086 kHz) in order to investigate if results from studies performed with single model compounds in water can be applied to a natural ground water. It was shown that the treated highly volatile halogenated hydrocarbons are almost completely destroyed by ultrasound in natural ground water within 60 min. It also transpired that the naturally occurring inorganic components and gases in the ground water play an important role. 相似文献
112.
Justin Peters 《Journal of Functional Analysis》1984,59(3):498-534
Given a C1-algebra and endomorphim α, there is an associated nonselfadjoint operator algebra + Xα, called the semi-crossed product of with α. If α is an automorphim, + Xα can be identified with a subalgebra of the C1-crossed product + Xα. If is commutative and α is an automorphim satisfying certain conditions, + Xα is an operator algebra of the type studied by Arveson and Josephson. Suppose S is a locally compact Hausdorff space, φ: S → S is a continuous and proper map, and α is the endomorphim of U=C0(S) given by α(?) = ? ō φ. Necessary and sufficient conditions on the map φ are given to insure that the semi-crossed product Z+XαC0(S) is (i) semiprime; (ii) semisimple; (ii) strongly semisimple. 相似文献
113.
114.
Contributions to the Chemistry of Silicon-Sulphur Compounds. 53. Structure of 1,3-Dimethyl-1,1,3,3-tetraphenyldisilthiane 1,3-Dimethyl-1,1,3,3-tetraphenyldisilthiane was obtained by an insertion reaction of sulphur with Ph2 MeSiH. The compound crystallizes triclinically (P1 ; a = 1166.7; b = 1231.1; c = 988.6 pm; α = 113.23; β = 90.34; γ = 112.43°; Z = 2). The X-ray structure analysis shows a bent configuration of the molecule with Si? S? Si = 108.7°. The results are discussed together with the structures of hexaphenyldisilthiane and dimethyltetraphenyldisiloxane. 相似文献
115.
Experimental results of fluid multiphase equilibria occurring in ternary mixtures of near-critical carbon dioxide, certain n-alkanols and tetradecane are presented. The following n-alkanols were used in this investigation: decanol, octanol, heptanol, hexanol and pentanol. In the ternary systems with decanol, octanol or heptanol a closed loop liquid-vapor two-phase region in the three-phase surface liquid-liquid-vapor was found. As far as the ternary system with decanol is concerned, this phenomenon is in agreement with an earlier and unexpected finding of Patton et al. (1993). In addition, it was also found in this study that the phase diagrams of the ternary mixtures with hexanol or pentanol as the n-alkanol show further complications. 相似文献
116.
Ziegler Erich Wittmann Helga Peters Karl 《Monatshefte für Chemie / Chemical Monthly》1983,114(6-7):783-787
Monatshefte für Chemie - Chemical Monthly - The crystal structure of1 was determined by X-ray structure analysis. Some further chemical reactions are presented which are in full accord with... 相似文献
117.
We present Doppler resolution limited spectra of the P(J) and R(J) multiplets for J ≦ 10 of the 10-μm CO stretch band of 12CD316OH using a tunable diode laser. Relative frequencies within the multiplets accurate to ±0.0002–0.0005 cm?1 are obtained, but no absolute frequencies are given. We are able to assign most of the hindered rotation and K substructure in these multiplets. The assignments are based on analyses of Stark-difference spectra combined with the ground-state microwave data and the intensity variations which are expected theoretically. The ground and excited state A, K = 1 asymmetry splitting parameters are measured to be δ1″ = (8.5450 ± 0.0080) × 10?3cm?1 and δ1′ = (9.7706 ± 0.0080) × 10?3cm?1, respectively. The ground-state value agrees well with the microwave results. A rapid-scan system for recording data and a computer-aided technique for calibrating and plotting the spectra are described. 相似文献
118.
119.
G. Peters 《Fresenius' Journal of Analytical Chemistry》1967,232(2):132
Ohne Zusammenfassung 相似文献
120.