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排序方式: 共有220条查询结果,搜索用时 187 毫秒
1.
D. Bisello G. Busetto A. Castro M. Nigro M. Penzo L. Pescara M. Posocco P. Sartori L. Stanco Z. Ajaltouni A. Falvard J. Jousset B. Michel J. C. Montret A. Antonelli R. Baldini A. Calcaterra G. Capon M. Schioppa J. -E. Augustin G. Cosme F. Couchot B. Dudelzak F. Fulda G. Grosdidier B. Jean-Marie S. Jullian D. Lalanne V. Lepeltier F. Manè C. Paulot R. Riskalla Ph. Roy G. Szklarz DM Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,39(1):13-19
Thee + e ?→K + K ? cross section has been measured from about 750 events in the energy interval \(1350 \leqq \sqrt s \leqq 2400 MeV\) with the DM2 detector at DCI. TheK ± form factor |F F ±| cannot be explained by the ρ, ω, ? and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment. 相似文献
2.
Reactions of 3-(ω-haloalkoxy)-2-hydroxypropyl sulfamates with amines or ammonia followed by acid hydrolysis give the corresponding
diaminohydroxyethers.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1663–1665, August, 1998. 相似文献
3.
4.
Smirnov O. Yu. Churakov A. M. Tyurin A. Yu. Strelenko Yu. A. Ioffe S. L. Tartakovsky V. A. 《Russian Chemical Bulletin》2002,51(10):1849-1856
Nucleophilic substitution in nitro- and bromobenzo-1,2,3,4-tetrazine 1,3-dioxides (BTDOs) was studied. In most cases, the bromo and nitro groups are replaced by methylamino, dimethylamino, azido, and methoxy groups without opening of the tetrazine ring. It was illustrated with the reactions of dibromo-BTDOs with sodium methoxide that the reactivity of positions 5 to 8 in their benzene ring as regards nucleophilic substitution changes in the following order: 6 > 8 > 7 > 5. The structures of the BTDOs obtained were confirmed by 1H, 13C, and 14N NMR data. 相似文献
5.
Alexander D Dilman Pavel A Belyakov Vladimir A Tartakovsky 《Tetrahedron letters》2004,45(19):3741-3744
Silyl enol ethers bearing three pentafluorophenyl groups at the silicon atom are described. These compounds undergo uncatalyzed aldol reactions with aliphatic, α,β-unsaturated, and aromatic aldehydes. The observed reactivity is analyzed in terms of the Lewis acidity of the silyl fragment. 相似文献
6.
A. M. Churakov A. Yu. Tyurin E. L. Goncharova S. L. Ioffe Yu. A. Strelenko V. A. Tartakovsky 《Russian Chemical Bulletin》1995,44(5):890-896
The addition of 1-aryl-2-bromodiazene 1-oxides to olefins yields 1-aryl-2-(2-bromoalkyl)diazene 1-oxides (4). A radical mechanism of the reaction has been suggested. Compounds4 decompose to give bromohydrazones of formaldehyde and aldehydes. The structural factors that affect the rate of this process are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 917–923, May, 1995.The work was carried out in the Scientific Educational Center of the Institute of Organic Chemistry of the RAS with financial support of the Russian Foundation for Basic Research (Project No. 93-03-18461). 相似文献
7.
A. Yu. Tyurin A. M. Churakov Yu. A. Strelenko M. O. Ratnikov V. A. Tartakovsky 《Russian Chemical Bulletin》2006,55(9):1648-1653
Thermolysis of o-diazidobenzotetrazine 1,3-dioxides was accompanied by cleavage of the C-C bond of the benzene ring to give nonannulated 1,2,3,4-tetrazine
1,3-dioxides. The structures of these first representatives of nonfused 1,2,3,4-tetrazines were confirmed by 13C and 14N NMR spectroscopy.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1589–1594, September, 2006. 相似文献
8.
Alexander D. Dilman Dmitry E. Arkhipov Valentine P. Ananikov Vladimir A. Tartakovsky 《Journal of organometallic chemistry》2005,690(16):3680-3689
A general method for the synthesis of carbon-centered tris(pentafluorophenyl)silyl derivatives (RSi(C6F5)3) by reaction of trichlorosilanes (RSiCl3) with pentafluorophenylmagnesium bromide was described. The crystal structures of obtained compounds were studied by X-ray diffraction analysis (7 structures). The peculiarities of crystal packing were analyzed by means of DFT calculations. 相似文献
9.
A. Yu. Tyurin A. M. Churakov S. L. Ioffe Yu. A. Strelenko V. A. Tartakovsky 《Russian Chemical Bulletin》1997,46(3):592-594
The reactions of 1-aryl-2-bromodiazene 1-oxides with HCl in nonaqueous media give aryldiazonium chlorides, while 1,3,3-substituted
triazenes-1 are formed in the reactions with secondary amines. Using 2-{15N} label, it was shown that the aryl group does not migrate in these reactions.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 613–615, March, 1997. 相似文献
10.
A. M. Churakov O. Yu. Smirnov S. L. Ioffe Yu. A. Strelenko V. A. Tartakovsky 《Russian Chemical Bulletin》1994,43(9):1532-1535
2-(tert-Butyl-NNO-azoxy)aniline was prepared by selective reduction of 2-(tert-butyl-NNO-azoxy)nitrobenzene. Its bromination yielded the correspondingpara-bromo- andortho, para-dibromoanilines (3a,b).meta-Bromoanilines (6a,b) were synthesized by selective replacement of theortho-bromine atoms in ortho,para-bromo(tert-butylazoxy)benzenes (5a,b) by ammonia in toluene under pressure.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1620–1623, September, 1994.This work was carried out with the financial support of the Russian Foundation for Basic Research (Project No. 93-03-18461). 相似文献