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Studies on the Mechanism of the Antimony Pentachloride Intercalation in Graphite The SbCl5 intercalation in graphite in liquid media (immersion in SbCl5 and in SbCl5/CCl4-mixtures, respectively) reveals an induction period ranging from 0,25 up to 8 hours. Graphite intercalation by liquid SbCl4F, SbCl2F3 and SbF5 does not exhibit any induction period. The induction time of synthetic graphites is shorter than that of natural graphites. The decrease of graphite particle sizes as well as the increase of SbCl5 concentration in CCl4 solution and the presence of co-reagents (e.g. SbCl3) reduce the induction time. Increasing the SbCl5 concentration in CCl4, an increase of SbCl5 quantity in graphite and of identity period along c-axis in stage 2 have been found. Gase phase intercalation of SbCl5 is a reaction of successive lowering of the stage index without any induction period. Using EPMA investigations it have been stated that nucleation at the prismatic edges (opening of galleries) controls the intercalation kinetics. An explanation of induction period and ?autocatalytic”? reaction after the induction period is given on basis of interaction of electrostatic forces, connected with adsorption of guest molecules, and elastic forces, resulting from dilatation during intercalation. Formation of complexes between SbCl5 and co-reagents (e. g. SbCl3) strengthens the electrostatic effect.  相似文献   

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Zusammenfassung Die Kondensation von Rhodanin und seinen 3-Äthyl-, Allyl-, Carboxymethyl-und Phenylderivaten mit Indol-3-aldehyd und 5-Bromindol-3-aldehyd wurde in saurem Medium untersucht und die Reaktionsfähigkeit der einzelnen Aldehyde bei dieser Reaktion miteinander verglichen und diskutiert. Zehn in dieser Weise dargestellte Indolmethylenrhodanine sollen auf ihre fungiciden und antibakteriellen Eigenschaften geprüft werden.An den Zuschriften zu richten sind.  相似文献   

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Studies on the Reactivity of Antimony Pentachloride. III. The Reaction of Antimony(V) Chloride and Methylisocyanate Methylisocyanate CH3NCO reacts with SbCl5 in boiling CCl4 by an insertion-reaction to a product of the formula C5H6Cl9N2O2Sb I, which has the chlorformamidinium-structure (Cl? C(O)? N(CH3)? CCl? N(CH3)? C(O)? Cl)⊕SbCl6?. Hydrolysis of I yields the heterocycle C5H6N2O4 II. The reaction with methanol gives (CH3? NH? CCl? NH? CH3)⊕SbCl6? III and (CH3? NH? CCl? N(CH3)? C(O)? OCH3)⊕SbCl6? IV. The i.r. and Raman spectra of the compounds I, III and IV are discussed.  相似文献   

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G. Beck 《Mikrochimica acta》1937,2(4):287-290
Zusammenfassung Morin liefert mit Aluminium-, Gallium-, Scandium- und Indiumsalzen grün fluoreszierende Verbindungen von verschiedener Beständigkeit. Durch Einhaltung bestimmter Versuchsbedingungen (Zusatz von Alkalifluorid, Ammoncarbonat, Ammontartrat oder Schwefelwasserstoff) ist es möglich, die genannten Elemente auch nebeneinander durch eine Reaktion mit Morin zu erkennen. Die Erfassungsgrenze für den Indiumnachweis im ultravioletten Licht beträgt 0,02 In.Es wird gezeigt, daß die Reduktion von Kakothelin außer durch Zinn(II)-Salze noch durch Titan(III)-, Uran(III)-, Rhenium(III)-Salze, durch niedere Molybdän- und Wolframoxyde sowie durch Niob(III)-Chlorid herbeigeführt wird, wobei die Erfassungsgrenzen etwa 1 des betreffenden Metalles betragen.
Summary Morine reacts with aluminium, sodium, gallium, scandium, and indium salts, thus forming compounds of a green fluorescence colour and different stability. It is possible to recognize the elements mentioned, even in the presence of each other, by a morine reaction carried out under defined experimental conditions (i. e. addition of alkali fluoride, ammonium carbonate, ammonium tartrate, or sulphide of hydrogen). The limit of identification of indium in ultra-violet light is 0,02 In.It is shown that reduction of cacothelin is effected not only by tin (II) salts but also by titanium (III), uranium (IV), rhenium (III) salts, low oxydes of molybdene and tungsten, and by columbium (III) chloride, the limits of identification being about 1 of the metal in question.

Rèsume La morine fournit avec des sels d'aluminium, de gallium, de scandium et d'indium des combinaisons à fluorescence verte, différemment stables. En observant exactement certaines conditions de travail (addition de fluoride d'alcali, de carbonate d'ammonium, de tartrate d'ammonium ou d'hydrogène sulfuré), il est même possible, de reconnaître les éléments mentionnés, l'un à côté de l'autre à l'aide d'une réaction de morine. Dans la lumière ultraviolette, il est possible, de déceler jusqu'à 0,02 d'indium.L'auteur montre, que la réduction de la cacothéline peut être amenée, de même que par les sels d'étain, par le titane (III), l'urane (III), le rhénium (III), ainsi que par des oxydes de molybdène et de tungstène et par le chlorure de niobium. On peut déceler jusqu'à 1 du métal cherché.
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Pyridylthioureas were prepared by hydrolysis and decarboxylation of the corresponding N-ethoxycarbonyl-N-pyridylthioureas. Pyridylthioureas reacted with esters of acetylene dicarboxylic acid to form derivatives of thiazolinone (6).  相似文献   

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