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951.
V. A. Dyachenko E. M. Kuramshin S. S. Zlotskii D. L. Rakhmankulov 《Reaction Kinetics and Catalysis Letters》1987,33(1):63-66
Liquid phase oxidation of cycloalkane diheteroanalogs catalyzed by compounds of Cu2+, Ni2+, Co2+, Cr3+, Fe3+ has been studied. It has been established that these catalysts can be applied to intensify, oxidize and increase the selectivity of this process.
: Cu2, Ni2+, Co2+, Cr3+, Fe3+. .相似文献
952.
L. V. Malysheva E. A. Paukshtis N. S. Kotsarenko 《Reaction Kinetics and Catalysis Letters》1984,24(1-2):91-95
Studies of the deamination of tert-, sec- and n-butylamines on several silicate and phosphate catalysts at 543–704 K have revealed that the reaction proceeds only with the participation of protonic cneters, its rate is independent of the strength of acidic centers and affected only by the amine structure. Butylammonium ion conversion is suggested to be the rate-determining step.
-, - - 543–703 . , . , . , .相似文献
953.
Summary The acid base properties of solochrome violet R.S. has been studied with the object of testing its use as an acid base indicator or as a colorimetric reagent. The pk values of 4.35, 7.4, and 9.45 corresponding to the three steps of ionisation of the free acid were evaluated by the aid of the relation between log (acid)/(salt) and ph values obtained during the course of the potentiometric titration of the free acid with a free base. The dye has proved to be a suitable indicator in titrating some mineral and organic acids as well as a colorimetric reagent for the microdetermination of vanadium. 相似文献
954.
V. I. Myagkikh V. M. Zaskulnikov V. A. Tolkachev 《Reaction Kinetics and Catalysis Letters》1980,14(1):73-76
The effect of matrix annealing on ethyl radical oxidation in excess oxygen has been studied by an ESR method. The annealing decelerates the nonstationary kinetics making it close to the exponential one. It has been shown that the nonstationarity cannot be attributed only to annealing.
. . , .相似文献
955.
H. Antropiusová K. Mach V. Hanu F. Tureek P. Sedmera 《Reaction Kinetics and Catalysis Letters》1979,10(4):297-300
The system Cp2TiCl2–LiAlH4, in the absence of ethereal solvents, catalyzes the intramolecular cyclization of Z,E,E-1,5,9-cyclododecatriene, yielding a mixture of C12 hydrocarbons consisting mainly of cis, anti, cis-and cis, syn, trans-tricyclo [7.3.0.02,6] dodec-7-ene and 5,6,7,8,9,10-hexahydrobenzocyclooctene.
Cp2TiCl2–LiAlH4, , Z,E,E,-1,5,9-, C12, , , - , , - [7.3.0.0.2,6] -7, 5,6,7,8,9,10-.相似文献
956.
IntroductionCatal}ticrcactionsaffcctcdb}'diffosionaIlimitationincatal}'stporcshavcbccnextensive1}dcaltx`ithinlit.rat.rcll~5I.Scvcraltcchniqucsonthcspccialcase0fFischcr-Tropschs}'nthcsis(FTS)t\crcapplicdtocxplorcthebchaviorofthiscatal}ticrcactionundercxpcrimcntalandopcrationaIconditionsI3~5l.It`"ouldbeofvaluctoindicatchcrcthatthcseinvcstigationsx"ercmainl}'bascdonthesimplcstkineticsofthcfirstordcrinH2proposedbyAndersonl6]attheearIystages.However-thesetboents,striCtlyspeaking,areinvalidfor… 相似文献
957.
T. P. Elango V. Ramakrishnan S. Vancheesan J. C. Kuriacose 《Journal of Chemical Sciences》1984,93(1):47-52
Rate constants for the reaction of carbonate radical with aniline and some parasubstituted anilines have been determined by
the flash photolysis technique. Using σ+ para values the rate constants at pH 8.5 correlate very well with the Hammett equation yielding ρ= − 1. The carbonate radical oxidises aniline giving the anilino radical. The products so formed have been identified through
studies under conditions of continuous irradiation. 相似文献
958.
相转移催化元素硫的歧化反应 总被引:1,自引:0,他引:1
本工作将相转移催化(PTC)应用于元素硫歧化反应,大大降低了反应温度,提高了反应速度。该反应被证实与熔态硫在水溶液中的歧化相同,即4S+6OH~-=2S~(2-)+S_2O_3~(2-)+3H_2O。比较了四乙基铵、四丁基铵、十六烷基三甲基铵和三辛基甲基铵四种相转移催化剂及四氯乙烯、二甲苯和四氯乙烷三种溶剂的影响。讨论了本体系相转移催化的证据。为改进以元素硫歧化反应为基础的提取冶金过程提供了依据。 相似文献
959.
叙述了用θ-2θ型X射线衍射仪精确测定电解质溶液结构的新实验技术。设计制作了具有恒温功能的超厚液体样品池,并建立了样品池窗口强度的校正方法。优化了液体X射线衍射数据和结构参数精细化的计算机程序,获得了非常令人满意的实验结果。由θ-2θ型X射线衍射仪精确测定的径向分布函数与θ-θ型衍射仪自由散射比较,表明DRF分辨率有所提高。 相似文献
960.
O. V. Bryanskii V. V. Tolstikhina S. V. Zinchenko A. A. Semenov 《Chemistry of Natural Compounds》1993,28(6):556-560
A sesquiterpene glucoside has been isolated from a tissue culture ofScorzonera hispanica, and its structure has been established by mass spectrometry and two-dimensional NMR as 6,9-dihydroxy-4,10,14,15-tetradehydroguaian-6,12-olide 9-O--D-glucopyranoside.Irkursk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 640–645, November–December, 1992. 相似文献