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21.
SOLIMAN A.Y. BAKEER H.M. ATTIA LA.Science Department Faculty of Teachers P.O.Box Alhasa Saudi Arabia Chemistry Department Faculty of Science Fayoum Cairo University EgyptFaculty of Engineering Ain Shames University Egypt 《中国化学》1996,14(6):532-540
3-(4-Phenyl) benzoyl propionic acid was used as the starting material for the synthesisof furanones (2), pyrrolinones (5), pyridazinones (7), benzoxazinones (8) and quinazolinones (9-11). The behaviour of the derivatives of furanones and benzoxazinones toward different nucleophiles is reported. 相似文献
22.
23.
Hsueh SY Muller D Tang J Winston R Zapalac G Swallow EC Berge JP Brenner AE Grafstrom P Jastrzembski E Lach J Marriner J Raja R Smith VJ McCliment E Newsom C Anderson EW Denisov AS Grachev VT Kulikov AV Schegelsky VA Seliverstov DM Smirnov NN Terentyev NK Tkatch II Vorobyov AA Cooper PS Razis P Teig LJ 《Physical review letters》1985,54(22):2399-2402
24.
S. I. Kulakovskaya A. V. Kulikov A. F. Shestakov 《Russian Journal of Electrochemistry》2007,43(10):1156-1163
The mechanism of oxidation of 2,5-dimethyl-, 2,3,5,6-tetramethyl-, 2,3-dimethyl-5,6-cyclohexa, and 3-phenyl-5,6-cyclohexapyrazine-di-N-oxides is studied by cyclic voltammetry, quantum chemical simulations, and ESR electrolysis. The studies are carried out on electrodes of glassy carbon and Pt in 0.1 M LiClO4 solutions in acetonitrile. ESR spectra of radical cations of substituted pyrazine-di-N-oxides are recorded. The effects of the temperature, oxygen, and the additions of water, pyridine, and acid on the shape of cyclic voltamograms and the intensity of ESR signals of pyrazine-di-N-oxides are studied. A quantum-chemical simulation of the reaction of pyrazine-di-N-oxide radical cations with acetonitrile is carried out. The oxidation of substituted pyrazine-di-N-oxides is described by the E1C1E2C2 mechanism, which includes the stage of the formation of a complex between the di-N-oxide radical cation and acetonitrile. 相似文献
25.
M. V. Kulikov 《Russian Chemical Bulletin》1998,47(12):2399-2403
The specific heat capacities of hexamethylphosphoric triamide, diethylpropionamide, their aqueous solutions, and mixtures
of hexamethylphosphoric triamide with formamide were measured in the temperature range from 288.15 to 318.15 K. The dependences
of the partial molar heat capacity of aqueous solutions of amides on the composition of the mixture have maxima in the region
of 0.02–0.04 molar fractions of amide. The maximum on a similar dependence for solutions of hexamethylphosphoric triamide
corresponds to the concentration of 0.01 molar fractions. The conclusion on the formation of solvates (hydrates) in the systems
studied was made. The heat capacity coefficients of pair and triple interactions were calculated in terms of the McMillan-Mayer
theory. A change in the heat capacity characteristics with the temperature change was analyzed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2479–2483, December, 1998. 相似文献
26.
MENG Jian REN Yu-Fang LI Xiao-GuangLaboratory of Rare Earth Chemistry Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin ChinaPopov V.V. Repin S.M. Smirnov LA. loffe Physicotechnical Institute Russian Academy of Sciences Saint Petersburg Russia 《中国化学》1994,12(5):419-424
YBa2Cu3-xVxO7-y(x=0, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) superconductors have been prepared. X-ray diffraction shows that the system remains orthorhombic for all compositions studied, but for x > 0.4 V2O5 was detected as an impurity phase. Substitution of V5+ for Cu2+ occurs in the Cu(2) sites on the Cu(2)-O planes. The introduction of the high valence element, vanadium, produces the extra free-electrons. These electrons recombine with the positive carrier of the system. It makes depression of the mobility and the Hall number of YBa2Cu3-xVxO7-v and also results in a depression of TC. 相似文献
27.
A. S. Kulikov M. A. Epishina I. V. Ovchinnikov N. N. Makhova 《Russian Chemical Bulletin》2007,56(8):1580-1587
The conditions for the thermolysis of furoxans annulated with differently strained five-membered carbocycles (cyclopentafuroxan
1, norbornenofuroxan 2, and acenaphthofuroxan 3) to bis(nitrile oxides) in the presence of various dipolarophiles (diethyl acetylenedicarboxylate, benzoylformonitrile, and
ethoxycarbonylformonitrile) were optimized. It was found that the reactivities of the above furoxans as sources of bis(nitrile
oxides) decrease in the order 2 > 1 > 3. Among the furoxans studied, only norbornenofuroxan 2 can be recommended as a possible cross-linking reagent for polymers. The formation of di-N-oxides of 3,4-bis(cyanopropyl)-, 3,4-bis(cyanocyclopentyl)-, and 3,4-bis(cyanonaphthyl)furoxans was detected. They resulted
from intermolecular cyclodimerization of bis(nitrile oxides) initially formed in the thermolysis of furoxans 1–3.
Dedicated to Academician V. A. Tartakovsky on the occasion of his 75th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1521–1528, August, 2007. 相似文献
28.
MARIAN ELBANOWSKI MARIA PAETZ JANUSZ SIAWINSKI LESZEK CIELA 《Photochemistry and photobiology》1988,47(3):463-466
Abstract— Chemiluminescence of the Eu(II)/Eu(III)-adenine nucleotide-H2 O2 system and fluorescence of the Eu(III)-adenosine triphosphate system have been investigated. The spectral distribution of the chemiluminescence emission has shown an occurrence of three main bands (Λ=470–480,590–620 and ca. 700 nm). The energy transfer process from the adenosine triphosphate molecules to the Eu(III) ions has been observed in the fluorescence spectrum. The examined chemiluminescence and fluorescence spectra show that these both kinds of emission originate from the 5 D *** τ7 F*** ( n =1–4) transitions in the Eu(III) ions. 相似文献
29.
V. I. Shitova M. A. Samartsev S. V. Kulikov N. V. Belyakov 《Chemistry of Natural Compounds》1981,17(3):288-293
The heat stability, substrate specificity, and the pH optima of activation and inhibition of an acid proteinase isolated from the industrial preparation amilorizin Pkh have been studied. The enzyme has been found active in the hydrolysis of chromophoric peptide substrates of the type of Dnp-Gly-Gly-X-Arg-OH, where X = Phe, Met, Trp. Inhibition of the enzymatic activity by pepstatin and covalent inhibitors of carboxylic proteinases show that this enzyme belongs to the proteinases of the pepsin type. 相似文献
30.
G. G. Saveliev N. F. Kulikov M. M. Mikhailov M. I. Dvoretskii 《Reaction Kinetics and Catalysis Letters》1984,26(3-4):269-272
The chemical action of atoms on solids can be due to both direct reactions with the structural units of solids and heterogeneous recombination energy transfer to the crystal lattice.
, .相似文献