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961.
The vibrational distribution of CO produced from the following two electronic-to-vibrational energy transfer reactions:
have been determined by means of infrared resonance absorption measurements employing a cw CO laser. The CO molecules formed in both reactions were found to be vibrationally excited up to the limits of available electronic energies carried by the excited atoms. A similar result was also observed in the Br(42P12) + CO reaction, in which absorption occurred only in the 1 → 2 band. For the O* + CO reaction the efficiency of E → V energy transfer was determined to be 16%. Our present results were found to be inconsistent with the impulsive (half-collision) model.  相似文献   
962.
The arylation of fluorobenzene with pentafluorophenyl radicals obtained by the reaction of the corresponding aniline with pentyl nitrite is described. The reaction involves attact at the 2t?-,3t?-and 4t?-positions. The composition of the mixture and the nature of its components were determined by 19F NMR spectroscopy and were confirmed by gas-liquid chromatography.  相似文献   
963.
The thermal reactions of pure metal(11) 4,4′,4″,4′″-phthalocyanine-tetracarboxylic acids of copper, cobalt, and nickel at 350–400°C in vacuum have been studied using Fourier transform infrared spectrometry, gas chromatography, and mass spectrometry. Based on these observations, novel in situ reactions for the synthesis of heat-resistant phthalocyanine “sheet” polymers are described. The poly(metal phthalocyanine) polymers of copper, cobalt, and nickel so synthesized have been characterized by elemental analysis, infrared spectroscopy, and dynamic thermogravimetric analysis. The most noteworthy property of these polymers is their extreme resistance to heat in an anaerobic atmosphere and their high char yields (89–93%) at 800°C in a nitrogen atmosphere.  相似文献   
964.
The reaction of indoles (1) with superoxide ion resulted in ring cleavage to give o-formyl and o-acylaminoketones (6) or N-acylanthranilic acid (8) and ring expansion yielding 2-quinolones (7). All reactions are chemiluminescent except that of 2-methylindole (lh), which gave a coupled product (9).  相似文献   
965.
Summary Three cardiac glycosides have been synthesized from gitoxigenin and D-glucose: gitoxigenin 3-O--D-glucopyranoside, gitoxigenin 16 -O- -D-glucopyranoside, and gitoxigenin 3, 16-di-O- -D-glucoside. The first glycoside, obtained with a yield of 49% on the weight of the initial aglycone, possesses a fairly high biological activity (0.25 mg/kg), while the other two, formed in a yield of about 0.3%, do not possess the action on the heart that is specific for the cardenolides.Khar'kov Chemical and Pharmaceutical Scientific-Research Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 45–49, January, 1971.  相似文献   
966.
The selective degradation of polyethylene crystals with fuming nitric acid has been used to prepare a C100 chain with terminal functional groups. After treating this product with concentrated sulphuric acid, it is shown by average molecular weight, titration and infra-red spectroscopy measurements that each molecule contains two carboxylic acid groups. This C100 dicarboxylic acid is chain extended with several low molecular weight difunctional coupling agents. Block copolymers of this acid and poly(propylene glycol) have been prepared.  相似文献   
967.
Electrical Conductivity of Molten Strontium Chloride-Alkali Chloride Salt Mixtures The temperature and concentration dependence of the specific electrical conductivity is measured for binary fused mixtures SrCl2–MeCl (Me = Li, Na, K, Rb, Cs). Minima of the conductivity are found at the concentration x · 0.5 in the systems SrCl2–(KCl, RbCl, CsCl).  相似文献   
968.
Zusammenfassung Die Methode von Bonsels u. Linnemann [1] zur Bestimmung von FeII und MnIII lieferte bei der Überprüfung falsche Ergebnisse. Die Ursache liegt darin, daß sich der Blindwert des Azides in Gegenwart von Mn-Ionen erheblich erhöht und in der Siedehitze eine Reaktion zwischen MnIII und CrIII abläuft. Da eine Auflösung selbst fein pulverisierter Ferrite in dem mitgeteilten Lösungsgemisch nur in der Siedehitze erfolgt, ist eine Bestimmung von FeII und MnIII in Ferriten nach dieser Methode nicht möglich.
Summary The method for the determination of FeII and MnIII in manganese ferrites by Bonsels and Linnemann [1] was examined. It was found that the consumption of NaN3, used for the reduction of MnIII and effecting in a second (not wanted) reaction the reduction of Cr2O7 2–, is essentially increased by the presence of MnII and causes an error in the determination of FeII. The second error is the reaction between MnIII and CrIII at boiling temperature. On account of the necessity to dissolve the ferrites with the acid mixture at boiling temperature the determination of MnIII and FeII is not possible.


Herrn Dr. P. Kleinert vom Institut für Magnetische Werkstoffe danken wir an dieser Stelle für wertvolle Diskussionsbeiträge und das bei der Durchführung der Arbeit gezeigte Interesse.  相似文献   
969.
Résumé Les monophénols sont isolés des condensats de fumées de cigarette par chromatographie sur couche mince de Kieselgel G avec un mélange (31) de cyclohexane et d'acétate d'éthyle extraits du support, puis séparé et dosés par chromatographie en phase gazeuse sur colonne capillaire. Le rendement de l;opération est de 80±2% pour le triméthyl 3,4,5 phénol, de 65% pour le triméthyl 2,3,5 phénol. Les teneurs obtenues sont de 8g de phénol, 3g de (para + méta) crésol et 0,5 g de diméthyl 2,6 phénol par mg de condensat. De nombreux autres alkylphénols ont été identifiés.
Analysis of the monophenolic fraction of tobacco smoke condensates by a combination of chromatographic methods
Summary Monophenols are separated from tobacco smoke condensates by thin-layer chromatography on Kieselgel G using a 31 mixture of cyclohexane and ethylacetate. The monophenolic fraction is recovered from the support and analyzed by GC on a capillary column. The yield is 80±2% for 3,4,5 trimethylphenol and 65% for 2,3,5 trimethylphenol. The concentration determined for phenol, (para+meta) cresol and 2,6 dimethylphenol are 8,3 and 0.5 g per mg of condensate respectively. Numerous other alkyl phenols have been identified.
  相似文献   
970.
Conclusions Both the nucleophilic and the free radical addition of n-butyl mercaptan to acetylenic-hydroxy ketones (1,1-disubstituted derivatives of 2-pentyn-1-ol-4-one) lead to the formation of the corresponding 1,1-disubstituted derivatives of 2-butylthio-2-penten-1-ol-4-one in 41–65% yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1669–1670, July, 1973.  相似文献   
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