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排序方式: 共有292条查询结果,搜索用时 6 毫秒
1.
N. S. Prostakov B. Kh. Sisimbina S. A. Soldatova V. P. Shalimov K. G. Montenegro N. I. Leonova L. A. Murugova 《Chemistry of Heterocyclic Compounds》1982,18(12):1290-1294
Isomeric (with respect to the position of the nitrogen atom) azafluorenes were cyanoethylated. The resulting 9,9-bis(-cyanoethyl) derivatives were converted to the corresponding dibasic acids and their diesters. The latter were subjected to the Dieckmann reaction to obtain spiro compounds with azafluorene and cyclohexene fragments. The analogous spirans with 1,3-dioxalane and 1,3-dioxane rings were obtained from 3-methyl-2-azafluorenone.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1668–1672, December, 1982. 相似文献
2.
The behavior of electrochemical cells Pt(sponge)/Na5TbSi412/Na0.65Co2(cell I) and Pt(sponge)/Na5TbSi412/Pt(sponge) (cell II) is studied by, respectively, potentiometric and impedance methods in oxygen and argon atmospheres at 50–300°C. Dependence of potential of cell I on the oxygen concentration is affected by the grain size of platinum sponge and the temperature. At 50–200°C the coarse-grained platinum electrode in contact with solid electrolyte Na5TbSi412 exhibits an oxygen function characterized by the potential-determining reaction 2(g) + 2 + 2 = –
2 + –. An impedance method shows the triple-phase boundary 2, Pt(sponge)/Na5TbSi412 to be reversible with respect to oxygen. The reversibility is realized by minority charge carriers in the solid electrolyte, i.e. by oxygen ions. 相似文献
3.
A.N. Nesmeyanov E.V. Leonova N.S. Kochetkova A.I. Malkova 《Journal of organometallic chemistry》1975,96(2):271-274
A method is described for the preparation of 1,2-diacetylferrocene, in which ferrocene is acetylated with acetyl chloride in the presence of AlCl3 in methylene chloride. Addition of the ferrocene to an excess of the acetylation mixture over a prolonged period was found to be most favourable. The 1,2-diacetylferrocene formed proved to be free of the 1,3-isomer. It was reduced with LiAlH4/AlCl3 to 1,2-diethylferrocene. 相似文献
4.
L.O. Atovmyan O.S. Filipenko V.I. Ponomarev L.S. Leonova E.A. Ukshe 《Solid State Ionics》1984,14(2):137-142
Conductivity measurements of the crystals of the N5RESi4O12 family, where RE=Sm→Lu, have been made. A reversible phase transition R32Rc has been established. The conductive channels have been determined using a high temperature X-ray structural analysis of the Na5RESi4O12 crystals, as well as the ion exchanged Ag phase. 相似文献
5.
Larionov S. V. Leonova T. G. Glinskaya L. A. Klevtsova R. F. Platonov V. E. Maksimov A. M. Fadeeva V. P. Batrachenko N. I. 《Russian Journal of Coordination Chemistry》2000,26(12):861-865
Compounds (CH3)2Sn(C12F9S)2 (I), (CH3)2Sn(C10F7S)2 (II), and (C2H5)2Sn(C10F7S)2 (III) were synthesized. Single crystals of Iwere grown and structurally characterized using X-ray diffraction analysis (1590 reflections, R = 0.0209). The crystals are orthorhombic, a = 40.848(8) Å, b = 6.058(1) Å, c = 11.183(2) Å, V = 2767(1) Å3, (calcd.) = 2.024 g/cm3, space group Pbcn, Z = 4. The structure is built from monomeric molecules. The coordination polyhedron of the Sn atom (the SnC2S2 core) is a distorted tetrahedron. Compounds I–III are volatile when heated in vacuo. Thermolysis of these compounds results in SnO2 (in air) or SnS2 (in argon). 相似文献
6.
L. A. Frolova L. S. Leonova A. A. Arslanova Yu. A. Dobrovol’skii 《Russian Journal of Electrochemistry》2013,49(8):822-826
Effective catalytic systems based on Pt/CeO2-C were prepared. The use of a cerium oxide addition in the substrate stabilized the platinum catalysts against their poisoning with carbon monoxide at room temperature. 相似文献
7.
Zhanna A. Krasnaya Vladimir A. Kuz’min Lyubov V. Litvinkova Evgeniya O. Dorofeeva Sergei G. Zlotin 《Mendeleev Communications》2013,23(4):212-214
New bischromophoric dyes (thiacarbocyanine and thiadicarbocyanine) containing coumarin moieties at each of the two benzothiazole systems, as well as monomethinecyanine containing coumarin moiety at only one heterocyclic system, manifest significant batho-chromic shift compared to relative coumarin-free dyes. 相似文献
8.
M. V. Leonova M. Yu. Skomorokhov I. K. Moiseev Yu. N. Klimochkin 《Russian Journal of Organic Chemistry》2015,51(12):1703-1709
A one-pot procedure has been proposed for the synthesis of amines directly from cage hydrocarbons. A number of cage amines have been synthesized by treatment of adamantane, its homologs, and structurally related cage hydrocarbons with nitric acid in acetic acid and subsequent addition of urea and heating. 相似文献
9.
A. A. Bel’mesov A. V. Levchenko T. A. Palankoev L. S. Leonova A. E. Ukshe A. I. Chikin N. G. Bukun 《Russian Journal of Electrochemistry》2013,49(8):831-835
Electrocatalysts based on platinized titania modified with ruthenia (0–9 mol %) were studied. The synthesized materials were investigated as working electrodes in potentiometric sensors sensitive to hydrogen and carbon monoxide. All electrocatalysts showed reproducible behavior at pure gas concentrations from 400 to 4000 ppm. In CO-H2 mixtures with comparable concentrations of both gases, the sensors were selective toward hydrogen at ≥0.05 mol % Ru, but not selective to hydrogen or CO at less than 0.05 mol % Ru in the substrate. 相似文献
10.
A. A. Sokolov M. A. Syroeshkin V. N. Solkan T. V. Shebunina R. S. Begunov L. V. Mikhal’chenko M. Yu. Leonova V. P. Gultyai 《Russian Chemical Bulletin》2014,63(2):372-380
Electrochemical reduction of N-(2-nitroaryl)pyridinium chlorides in alcohol—dilute HCl mixtures gave pyrido[1,2-a]benzimidazoles in high yields in both divided and undivided cells. According to cyclic voltammetry measurements and DFT calculations (B3LYP/6-31+G(d)), the reaction involves intermediate formation of the corresponding hydroxylamine derivative followed by its heterocyclization. 相似文献