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51.
FRAN´OIS SAUVAGEOT 《Compositio Mathematica》1997,108(2):151-184
The main goal of this Letter is to give a new proof of a result conjectured by D. De George and N. Wallach and proved by P. Deborne and to extend it to the S-arithmetic setting. The proof is based on a density principle. 相似文献
52.
The bimetallic complexes [M(bipy)nS2M′X2], where M=FeII, RuII, NiII or CoII; bipy=2,2′-bipyridine; n=1 or 2; M′=MoVI or WVI
and X=O or S, were synthesized using tetrathiometallates and dithiometallates as bidentate ligands. The characterization of
the new bimetallic complexes was carried out by standard techniques. The complexes were tested as catalysts in acetonitrile
hydrolysis. The reaction products are acetamide and acetic acid, formed by hydrolysis of acetamide. The most active catalysts
in the acetonitrile hydrolysis are [Fe(bipy)2S2MoS2], [Ru(bipy)2S2MoS2] and [Co(bipy)2S2WS2], whereas the lowest activity
is shown by the nickel complexes. However, the latter exhibit the highest selectivity in acetamide formation.
ZINDO semi-empirical calculations were performed in order to explain some of the properties of the complexes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
53.
The efficient performance of two-dimensional surface-emitting laser arrays is analysed with the aid of a comprehensive fully
self-consistent three-dimensional thermal–electrical model. Maximal available output of the closely packed arrays is considered
as a function of their spacing and the emitter size. The superior thermal behaviour of arrays composed of small-size emitters
is found to be questionable.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
54.
55.
56.
E. A. Burakova I. V. Saranina N. V. Tikunova V. N. Sil´nikov 《Russian Chemical Bulletin》2015,64(6):1400-1405
Antibacterial activity of tetracationic compounds based on 1,4-diazabicyclo[2.2.2]octane (DABCO) bis-quaternary salts with dodecyl substituents bound by linker groups containing four carbon atoms was studied. All the compounds exhibited activity against the test-strains under study. The gram-positive culture S. aureus was found to be the most sensitive to the influence of compounds in question. The highest activity against S. aureus was exhibited by the compounds containing a but-2-yne or a butane linker; their efficiency exceeded that of the reference compound, antibiotic Ciprofloxacin. For the gram-negative culture P. aeruginosa, the highest activity was exhibited by the compound containing a but-2-yne linker. The compounds with a but-2-yne or a butane linker are stable in the presence of nitrogen-containing nucleophiles, which makes them promising for further studies. 相似文献
57.
L. I. Belen´kii M. Kh. Mamarakhmonov A. N. Subbotin N. D. Chuvylkin 《Russian Chemical Bulletin》2015,64(5):1032-1038
Density functional theory quantum chemical calculations of thermodynamic stabilities in the gas phase and in water were carried out for 1,3,4-oxadiazole and 1,3,4-thiadiazole, 1,2,4-1H-triazole and 1,2,4-4H-triazole, 1,2,3,4-1H-tetrazole and 1,2,3,4-2H-tetrazole molecules, and for cationic and bipolar (carbenoid) intermediates formed by these molecules in electrophilic substitution reactions (with proton as model electrophile) and the results obtained are compared. Differences in the chemical behavior of pairs of isomeric 1H- and 4H-1,2,4-triazoles and 1H- and 2H-tetrazoles are analyzed. 相似文献
58.
O. A. Luk´yanov G. V. Pokhvisneva T. V. Ternikova G. A. Smirnov 《Russian Chemical Bulletin》2015,64(5):1062-1064
Chlorides and anhydrides of carboxylic (including dicarboxylic) acids react with salts of 1-methoxy-3-methyl-1-triazene 2-oxides to give the corresponding 3-acyl-1-methoxy-3-methyl-1-triazene 2-oxides. 相似文献
59.
Rozhkov A. V. Basova G. V. Korshunov A. O. Bochkarev L. N. Glukhova T. A. Il´ichev V. A. 《Russian Chemical Bulletin》2015,64(8):1949-1954
Russian Chemical Bulletin - New norbornene monomer, viz., 5-[(bicyclo[2.2.1]hept-5-en-2-ylmethoxy)methyl]-8-[(dimesitylboryl)oxy]quinoline (1), was synthesized. The copolymers based on monomer 1... 相似文献
60.
Khisamutdinov G. Kh. Karpychev Yu. V. Zhbanova Yu. S. Kondyukov I. Z. Kashaev V. A. Il´in V. P. 《Russian Chemical Bulletin》2015,64(8):1967-1970
Known methods for the synthesis of 2,3-bis(nitroxymethyl)-2,3-dinitrobutane-1,4-diol dinitrate and its intermediates were investigated. New procedures were developed for the preparation of these compounds. 2,3-Bis(nitroxymethyl)-2,3-dinitrobutane-1,4-diol dinitrate was studied by X-ray diffraction.
相似文献