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11.
Photoconversion of lutetium diphthalocyanine and interpretation of its electronic absorption spectra
V. G. Maslov T. P. Prokof'eva A. N. Sidorov 《Theoretical and Experimental Chemistry》1990,25(5):564-568
When frozen solutions of lutetium diphthalocyanine (LuPC2) in a mixture of methylene chloride with trichloroethylene are irradiated by UV light, monocations of LuPC2 form. The photoreaction is slowed and ceases in an early stage apparently due to the reversibility of the photoconversion in this system. The reduced form of LuPC2 (its monoanions) are completely converted into the neutral form of LuPC2 during irradiation. When this photoconversion is carried out in a frozen solution, the electronic absorption bands in the spectrum of the LuPC2 formed are displaced in comparison to the bands of the original substance under the same conditions, posibly due to the difference between the structures of the solvation shells. An interpretation of the electronic absorption spectrum of LuPC2 in the 300–1600-nm region has been given on the basis of the scheme of the molecular orbitals of sandwich phthalocyanine dimer with one -electronic vacancy.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 5, pp. 614–618, September–October, 1989.We express our thanks to P. N. Moskalev for supplying the preparations of MIIIPC2. 相似文献
12.
K. A. Andrianov V. I. Sidorov M. G. Zaitseva L. M. Khananashvili 《Chemistry of Heterocyclic Compounds》1967,3(1):23-24
1,3-Dimethyl-3-vinyl-1,3-dichlorosiloxane is prepared by partial cohydrolysis of methylvinyldichlorosilane and methyldichlorosilane, and its cohydrolysis with sym-tetra-methyldichlorodisiloxane gives 1-hydro-3-vinylhexamethyl-cyclotetrasiloxane. A study is made of the kinetics of the polymerization of the latter in CCL4 in the presence of H2PtCl6 · 6H2O 相似文献
13.
Talismanova M. O. Sidorov A. A. Aleksandrov G. G. Oprunenko Yu. F. Eremenko I. L. Moiseev I. I. 《Russian Chemical Bulletin》2004,53(7):1507-1510
The new dinuclear palladium complex Pd2(-S,N-SC7H5N2)4 with a Chinese-lantern structure was synthesized by the reaction of K2PdCl4 with 2-mercaptobenzimidazole and structurally characterized by X-ray diffraction analysis. 相似文献
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15.
V. N. Charushin G. M. Petrova G. G. Aleksandrov L. G. Egorova A. I. Chernishev E. O. Sidorov N. A. Klyuev O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1987,23(4):426-435
Dibenzo[d,k]-1,3,6,10-tetraazatetracyclo[7.3.1.02,7.06,13]trideca-4,11-dienes undergo addition reactions at the C(2) carbon atom with alcohols and thiols, accompanied by cleavage of the C-N bond of the imidazoline ring, to generate diquinoxalino[1,2-a2,3-d]pyrrole derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 513–522, April, 1987. 相似文献
16.
V. A. Bakulev E. F. Dankova V. S. Mokrushin E. O. Sidorov A. T. Lebedev 《Chemistry of Heterocyclic Compounds》1987,23(6):698-701
5-Amino-1,2,3-thiadiazole-4-carbothioamides were obtained in the reaction of carbonyl derivatives of diazoacetonitrile with P4S10 and the Lawesson reagent. A novel recyclization of 1,2,3-thiadiazole-4-carbothioamides was observed.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 845–849, June, 1987. 相似文献
17.
In the interaction of ethioporphyrin and of several of its metal derivatives with negative ions of pyridine and anthracene in tetrahydrofuran solutions, an electron transfer takes place which results in the conversion of the pyridine and anthracene ions into neutral molecules, whereas the molecules of the pigment are first transformed into monovalent anions and subsequently into the di-, tri-, tetra-, and sometimes even into the hexavalent anions. In the first stage of this interaction, ferriethioporphyrin is reduced to ferro-ethioporphyrin, whereas the unmetallized pigment and its copper complex are transformed into the disodium derivative of ethioporphyrin. When the temperature is lowered, the rate of the electron transfer from pyridine ions to zinc-ethioporphyrin is decreased, and illumination leads to a substantial rate increase. The photochemical sensitivity of this system is possibly linked to the formation of stable complexes between pigment molecules and pyridine ions. 相似文献
18.
An. A. Kist A. G. Kist A. A. Kim A. N. Idrisova V. N. Sidorov Yu. Ya. Kit 《Journal of Radioanalytical and Nuclear Chemistry》1995,195(1):219-225
A general method for tritium labeling of organic compounds by the use of thermal activation of tritium is described. It allows obtaining uniformly tritium-labeled organic compounds with high specific activity (up to 50 Ci/mmol) which permits tracing the majority of the biodegradation products of compounds studied. More than 40 compounds were labeled using this simple, rapid and inexpensive method. Separation of the biodegradation products is performed by thin layer chromatography. Quantification is performed by direct measurement of the radioactivity by liquid scintillation counting after transfer of the layer from TLC plates into scintillation vials, or by densitometry of autoradiographs. The technique is useful for a wide range of organic compounds, including ones with unknown structure, and can be applied to various in vivo and in vitro studies. 相似文献
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20.
Tanskanen H Khriachtchev L Räsänen M Feldman VI Sukhov FF Orlov AY Tyurin DA 《The Journal of chemical physics》2005,123(6):64318
Vinyl radicals produced by annealing-induced reaction of mobilized hydrogen atoms with acetylene molecules in solid noble-gas matrices (Ar, Kr, and Xe) were characterized by Fourier transform infrared and electron paramagnetic resonance (EPR) spectroscopies. The hydrogen atoms were generated from acetylene by UV photolysis or fast electron irradiation. Two vibrational modes of the vinyl radical (nu7 and nu5) were assigned in IR absorption studies. The assignment is based on data for various isotopic substitutions (D and 13C) and confirmed by comparison with the EPR measurements and density-functional theory calculations. The data on the nu7 mode is in agreement with previous experimental and theoretical results whereas the nu5 frequency agrees well with the computational data but conflicts with the gas-phase IR emission results. 相似文献