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11.
I. B. Rozentsveig Yu. A. Aizina K. A. Chernyshev L. V. Klyba E. R. Zhanchipova E. N. Sukhomazova L. B. Krivdin G. G. Levkovskaya 《Russian Journal of General Chemistry》2007,77(5):926-931
The mixtures of mono-and dihalothiophenesulfonyl chlorides, formed in the sulfochlorination reaction of 2,5-dichlorothiophene
and 2,5-dibromothiophene, were treated with aqueous ammonia and thus converted into mixtures of the corresponding stable thiophenesulfonamides.
The structure and composition of the latter were studied by physicochemical methods: GC-MS and 1H, 13C, 1H-13C HSQC, 1H-13C HMBC, and NOESY NMR spectroscopy. As a result of the above chemical transformations, 2,5-dichlorothiophene afforded a mixture
of 5-chlorothiophene-2-sulfonamide and 4,5-dichlorothiophene-3-sulfonamide in a roughly 70:30 ratio. In the case of 2,5-dibromothiophene,
a mixture of 5-bromothiophene-2-sulfonamide, 4,5-dibromothiophene-3-sulfonamide, and 3,5-dibromothiophene-2-sulfonamide (3:54:43)
was formed.
Original Russian Text I.B. Rozentsveig, Yu.A. Aizina, K.A. Chernyshev, L.V. Klyba, E.R. Zhanchipova, E.N. Sukhomazova, L.B.
Krivdin, G.G. Levkovskaya, 2007, published in Zhurnal Obshchei Khimii, 2007, Vol. 77, No. 5, pp. 831–836. 相似文献
12.
V. D. Sheludyakov Z. V. Belyakova V. M. Shevchenko E. A. Chernyshev 《Russian Chemical Bulletin》1997,46(5):997-1002
Novel dialkylaminocarbenium salts with metallocomplex counter ions were prepared by the reaction of phosgene with either DMF
or tetramethylurea in the presence of metal chlorides. Reactions of organosilicon amides with phosgene gave corresponding
carbenium salts, while organosilicon ureas yielded aminoiminocarbenium salts. Dialkylaminochlorocarbenium salts were reduced
with hydrosilanes to give dialkylaminocarbenium, salts and can be easily hydrolyzed to afford either amides or ureas. Pathways
of the reaction with water and alcohols depend on the nature of reagent and the reaction conditions.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1035–1040, May 1997. 相似文献
13.
E. A. Chernyshev T. L. Krasnova E. S. Abramova E. A. Abronin A. B. Petrunin A. P. Sergeev 《Russian Chemical Bulletin》1997,46(9):1582-1585
Pyrolysis of trichlorosilane (TCS) and copyrolysis of TCS with 1,3-butadiene were studied. The enthalpies and activation energies
for the reactions of the products of TCS pyrolysis were found by quantum-chemical calculations. A direct study of the pyrolysis
of TCS by mass spectrometry was carried out. Based on the thermochemical parameters found by quantum-chemical calculations
and on the results of GLC and mass spectrometry concerning the composition of the pyrolysis products, it was concluded that
the pyrolysis of TCS follows a scheme that includes formation of radicals and silylenes.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1659–1662, September, 1997. 相似文献
14.
V. N. Bochkarev A. V. Kisin V. G. Osipov N. P. Telegina N. G. Komalenkova A. N. Polivanov E. A. Chernyshev 《Chemistry of Heterocyclic Compounds》1978,14(1):17-18
Workup of the mixture of products of pyrolysis of cyclotetrasiloxane (Me2SiO)2(MePhSiO)2 yielded 1,3- (I) and 1,5-(o-phenylene)cyclosiloxane (II), the structures of which were established on the basis of data from their IR, PMR, and mass spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 24–25, January, 1978. 相似文献
15.
A. I. V'yugin E. V. Antina D. V. Chernyshev G. A. Krestov 《Russian Chemical Bulletin》1992,41(7):1190-1192
Features of the solvation of zinctetraphenylporphyrin (ZnTPP) in benzene, toluene,ortho-, meta-, andpara-xylenes were studied by a thermogravimetric method. The temperature ranges of the stability and the compositions of the corresponding specific - complexes were determined from the results of the thermogravimetric investigation of the crystallosolvates of the metalloporphyrin with the solvent molecules, and the energy characteristics of the intermolecular metalloporphyrin—solvent interactions were calculated.Institute of the Chemistry of Nonaqueous Solutions, Russian Academy of Sciences, 153018 Ivanovo. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1545–1548, July, 1992. 相似文献
16.
Kirilin A. D. Belova L. O. Zhvakina L. A. Chernyshev E. A. 《Russian Journal of General Chemistry》2003,73(10):1539-1542
The reaction of chloro(chlorodimethyl)dimethylsilane and hexamethyldisilazane with O-silylurethanes and nicotinic hydrazide gives rise to products whose structure is determined by the composition, structure, and basicity of intermediate compounds. The reaction allowed synthesis of previously unknown linear and heterocyclic compounds. 相似文献
17.
Spectroscopic characterization of mineral crystals produced by the bacterium Azospirillum brasilense
Kamnev AA Antonyuk LP Chernyshev AV Ignatov VV De Vargas MC 《Analytical and bioanalytical chemistry》1996,355(5-6):739-741
The results of spectroscopic structural and trace elemental analyses of mineral crystals produced by the soil nitrogen-fixing bacterium Azospirillum brasilense cultivated in a synthetic medium are presented and discussed. The mineral formed is shown to have a structure close to struvite (MgNH(4)PO(4) x 6H(2)O; ASTM file No. 15-762) with some differences which may be attributed to the presence of isomorphic admixtures of other cations (struvite is known to have a variety of forms). AAS/AES and ion chromatography analyses for a number of biologically important microelements and their role in the formation of the crystal structure, as well as some questions related to biomineralization are also discussed. 相似文献
18.
19.
E. A. Chernyshev O. V. Kuz'min A. V. Lebedev V. G. Zaikin A. I. Mikaya 《Russian Chemical Bulletin》1986,35(4):821-824
Conclusions The main products of the pyrolysis of 8,8-dimethyl-8-sila-2,3,4,5-tetrathiabicycIo-[4.3.0]nonane at 400 are 1,1-dimethylsilacyclopent-3-ene and 1,1-dimethyl-1-sila-2-thiacyclo-hexa-3, 5-diene, and at 600 carbon disulfide and thiophene; silacyclopentene is the sole reaction product, characteristic for the mass-spectrometric decomposition of the initial tetrasulfide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No, 4, pp. 902–905, April, 1986. 相似文献
20.
Reactions of organochlorosilanes with chloro-and organogermanes in the presence of aluminum chloride
V. I. Zhun’ I. V. Sbitneva A. N. Polivanov E. A. Chernyshev 《Russian Journal of General Chemistry》2006,76(10):1564-1570
The effect of substituents at the silicon and germanium atoms in reactions of organochlorosilanes with chloro-and organogermanes in the presence of aluminum chloride was studied. The only occurring process is the exchange of the chlorine atoms at Ge for the phenyl groups from Si; an increase in the number of methyl groups or chlorine atoms at Si promotes formation of phenyltrichlorogermane, and an increase in the number of phenyl groups or replacement of the chlorine atom at the Si atom by hydrogen leads to the formation of di-and triphenylchlorogermanes. Neither phenyl nor other radicals are transferred back from Ge to Si in the course of reactions of phenylgermanes with methylchlorosilanes in the presence of aluminum chloride; the only occurring processes are the exchange of the phenyl or methyl radicals bonded to Ge for the Cl atom bonded to Al and the disproportionation of phenylchlorogermanes. 相似文献