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981.
On Oxorhodates of Alkali Metals: β-LiRhO2 We prepared hitherto unknown β-LiRhO2 in form of black, cubic single crystals, O4–F4132, a = 841.27(6) pm, Z = 16. For a first time in case of such metal oxides we find one of the possible variants of order between the NaCl-type with random distribution and the complete ordered types like α-NaFeO2 as a single crystal (four-circle-diffractometer PW 1100, AgKα, 100 von 109 I0(hkl), R = 9.10%, Rw = 5.46%). The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, were calculated and discussed.  相似文献   
982.
The solid state reactions between TiO2 and Na2S2O8 or K2S2O8 have been investigated using TG, DTG, DTA, IR, and X-ray diffraction studies in the range of 20 to 1000°C.It has been shown that TiO2 reacts stoichiometrically (1 : 1) with Na2S2O8 in the range of 160 and 220°C forming the complex sodium monoperoxodisulfato—titanium(IV) as characterized by IR and X-ray analysis. The new complex then decomposes into the reactants above 190°C.An exothermic reaction has been observed between TiO2 and molten K2S2O7 at mole ratio 1:2 respectively and higher, in the range of 280 and 350°C. The IR and X-ray analyses have shown the formation of a complex namely, potassium tetrasulfato titanium(IV) for which the formula and structure have been proposed. This complex decomposes at higher temperatures into K2SO4 and a mixed sulfate of potassium and titanium. The mixed sulfate melts at 620°C and decomposes into K2SO4, TiO2, and the gaseous SO3.On the other hand, Na2S2O8 decomposes in a special mode producing a polymeric product of Na10S9O32. Decomposition of this species occurs after melting at 560°C into Na2SO4 and sulfur oxides. The decomposition reaction has been proved to be catalysed by TiO2 itself.  相似文献   
983.
2,5-Bis(perfluoro-n-heptyl)-, 2-perfluoroalkylether-5-perfluoro-n-heptyl-, and 2,5-bisperfluoroalkylether-1,3,4-oxadiazoles were synthesized and characterized. 2,5-Bis(perfluoro-n-heptyl)-1,3,4-oxadiazole was thermally and hydrolytically stable at 325°C; however, in the presence of air, degradation took place at 235°C. The perfluoroalkylether analogue exhibited thermal and hydrolytic stability at 325°C; it was found to be unaffected by Jet-A fuel and air at 235°C. At 325°C in air some degradation occured as evidenced by volatiles production, oxygen consumption, and 96% starting material recovery.  相似文献   
984.
Complexation of polymeric anion exchangers with transition metals was studied by polarographic and potentiometric titration techniques.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 10, 2004, pp. 1693–1698.Original Russian Text Copyright © 2004 by Ergozhin, Chalov, Kovrigina, Iskakova, Nikitina.  相似文献   
985.
A new scheme for the synthesis of dibenzodithiacrown ethers is proposed based on the use of substituted phenol derivatives as intermediates, prepared by aromatization of 2-alkylthio(arylthio)cyclohexanes during bromination. 1,7-Dithia-8,9,17,18-dibenzo-18-crown-6 and 1,10-dithia-11,12,20,21-dibenzo-21-crow-7 without isomers relative to position of the sulfur atoms have been synthesized, and also new thiadiazamacroheterocycles — 1,4,7-trioxa-10,19-dithia-13,16-diaza-12,17-dioxo-8,9,14,15,20,21-tribenzoheneicosane and 1,4,7,10-tetraoxa-13,22-dithia-16,19-diaza-15,20-dioxo-11,12,17,18,23,24-tribenzotetracosane.M. V. Lomonosov Moscow State University, Moscow 119899. M. V. Lomonosov Moscow State Academy for Fine Chemical Technology, Moscow 117571. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 121–127, January, 1997.  相似文献   
986.
Y. K. Sawa  N. Tsuji  S. Maeda 《Tetrahedron》1961,15(1-4):144-153
Sinomenine, an alkaloid of the Japanese plant Sinomenium acutum, was converted to the 4-phenylether by the Ullmann reaction in a good yield. The Clemmensen reduction of sinomenine-phenylether and of its derivatives gave (+)-3-methoxy-4-phenoxy-N-methyl-Δx-morphinan.

Hydrogenation and successive sodium-liquid ammonia reduction of (+)-3-methoxy-4-phenoxy-N-methyl-Δx-morphinan gave (+)-3-methoxy-N-methylmorphinan.  相似文献   

987.
J. Tsuji  M. Hara  K. Ohno 《Tetrahedron》1974,30(14):2143-2146
Palladium compounds and metallic palladium combined with phosphine are active catalysts of selective hydrosilylation of terminal olefins. Butadiene and trichlorosilane give a 1:1 adduct and trimethylsilane affords a 1:2 adduct. Special features of the palladium catalyzed hydrosilylation reactions are presented.  相似文献   
988.
Summary In the present investigations, the standardization of vanadium(II) solution against ferric and cupric salts has been described and a few visual indicators have been shown to be applicable in the above titrations. When iron(III) solution is added to vanadium(II) solution neutral red marks the end point for VII to VIII change. This change is also noted when vanadium(II) solution is added to ferric solution in the presence of excess of concentrated hydrochloric acid at an elevated temperature and neutral red and phenosafranine as visual indicators. Under the same conditions, the end point with eupric solution also corresponds to this change.When vanadium(II) solution is added to ferric solution at an elevated temperature in the presence of methylene blue or gallocyanine as visual indicators, the end point marks VII to VIV change. A mixture of iron and copper has also been titrated successfully with the help of visual indicators.
Zusammenfassung Zur Einstellung von Vanadium(II)-lösungen mit Eisen(III)- oder Kupfer(II)-salzen werden als visuelle Indicatoren Neutralrot, Phenosafranin, Methylenblau oder Gallocyanin benutzt. Bei Zugabe von Eisen(III)-lösung zur Vanadium(II)-lösung zeigt Neutralrot den Übergang VII VIII an. Dieser Übergang wird ebenfalls von Neutralrot und Phenosafranin angezeigt, wenn Vanadium(II)-lösung in Gegenwart von überschüssiger konz. Salzsäure bei erhöhter Temperatur zu Eisen(III)- oder Kupfer(II)-lösung gegeben wird. Der Übergang VII VIV wird von Methylenblau oder Gallocyanin angezeigt, wenn Eisen(III)-lösung bei erhöhter Temperatur mit Vanadium(II)-lösung titriert wird. Die Titration eines Gemisches von Eisen(III) und Kupfer(II) wird ebenfalls ausgeführt.


Thanks of the authors are due to the C.S.I.R. authorities for providing a Junior Research Fellowship to one of them (R.K.M.).  相似文献   
989.
Hydrated iron oxide or amorphous-Fe2O3·3.5 H2O (HFeO), hydrated titanium oxide (HTiO) and hydrated thorium oxide (HThO) were synthesized and their applicability for the decontamination of intermediate level liquid wastes (ILLW) was tested. The sorption of a few actinides like plutonium and americium on HFeO, 137Cs and 106Ru on HTiO and 90Sr on HThO was investigated as a function of pH, time and loading capacity of the hydrous oxide with metal ions. The influence of the total dissolved salt content was also monitored. Some of these parameters influenced the sorption behavior significantly. The radiation stability of these inorganic sorbents were studied by irradiating them up to 48 Mrad. Adsorbed actinides and fission products were successfully eluted from HFeO and from the mix-bed of HTiO and HThO by 0.5M nitric acid.The authors wish to thank Shri R. D. Changarani, Chief Superintendent NRG Facilities and Shri P. K. Dey, Head FRD for their valuable advice and constant support.  相似文献   
990.
Standard papers regulating the quality of waters of different types are considered. Procedures for determining water quality indexes are briefly reviewed.__________Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 8, 2005, pp. 886–893.Original Russian Text Copyright © 2005 by Kutseva, Kartashova, Tchamaev.  相似文献   
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