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21.
22.
N. K. Gusarova N. A. Chernysheva M. Ya. Khil'ko S. V. Yas'ko L. M. Sinegovskaya N. N. Chipanina N. A. Korchevin B. A. Trofimov 《Russian Journal of General Chemistry》2005,75(8):1247-1250
Selective monoaddition of carbonodithioate anions to divinyl sulfoxide gives rise to O-alkyl S-[2-(vinylsulfinyl)ethyl] carbonodithioates [ROC(S)SK, R = Et, Bu; 42–50°C, 6 h, NaHCO3, aqueous benzene]. 相似文献
23.
24.
L. V. Baikalova V. I. Sokol I. A. Zyryanova I. V. Fedyanin V. N. Khrustalev E. A. Zel’bst O. A. Tarasova V. S. Sergienko B. A. Trofimov 《Russian Journal of General Chemistry》2006,76(5):791-797
The crystal and molecular structures of bis(1-isopropenylimidazole)dichlorocobalt (C12H16Cl2·N4Co) [R 0.036 (R W 0.089) for 3229 unique reflections with I > 2σ(I)] and tetra(1-vinylimidazole)dichlorocobalt (C20H24Cl2N8Co) [R 0.031 (R W 0.072) for 1863 unique reflections with I > 2σ(I)] were determined. In these molecular complexes, the monodentate terminal 1-alkenylimidazole ligands coordinate to the metal via a “pyridine” nitrogen atom. In C12H16Cl2N4Co, the Co atom has a distorted tetrahedral 2N,2Cl coordination. The coordination polyhedron of cobalt in C20H24Cl2N8Co is a strongly elongated 4N,2Cl octahedron. The Co-N and Co-Cl bonds [Co-N 2.015(2) and 2.032(4) Å; Co-Cl 2.229(2) Å] in the tetrahedral complex C12H16Cl2N4Co are shorter than those in the octahedral complex C20H24Cl2N8Co [Co-N 2.134(2) and 2.157(2) Å; Co-Cl 2.518(1) Å]. In the structures of both complexes there are short contacts involving the Cl atoms. 相似文献
25.
V. I. Trofimov I. I. Chkheidze L. I. Belen'kii N. Ya. Buben 《Theoretical and Experimental Chemistry》1970,4(1):56-60
EPR has been used to measure the radiation yields of radicals (GR) in various classes of organic compounds containing heteroatoms: dialkyl disulfides, diphenyl- and dibenzyl disulfide, alkyl derivatives of thiophene, thiophenecarboxylic acids, halogen derivatives of thiophene, and saturated heterocyclic compounds containing nitrogen, oxygen, and sulfur atoms. It has been shown that 1) GR=0.2–1 per 100 eV in saturated disulfides and cyclic sulfides, while GR=3–8 per 100 eV in the corresponding hydrocarbons, alcohols, oxides, and alkyleneimines; 2) the introduction of a sulfur atom into aromatic compounds does not alter the radiation stability; 3) disturbance of the conjugation of halogen atoms and of the carboxyl group with the thiophene ring leads to a decrease in the radiation stability. It is suggested that the increased stability of sulfur-containing compounds may be due to the excitation of the electrons in the S atom at the d-orbitals, which lie appreciably lower in the sulfur atom than in the atoms of oxygen, nitrogen, and carbon, and the subsequent dissipation of the excitation energy. 相似文献
26.
Bzhezovskii V. M. Kalabin G. A. Aliev I. A. Donskikh V. I. Trofimov B. A. 《Russian Chemical Bulletin》1981,30(7):1225-1230
Conclusions We have examined the13C NMR spectra of para- and meta-substituted alkylthiobenzenes. Steric disruption of the p, -conjugation of sulfur with the aromatic fragment on increase in the size of the alkyl substituents is typical of all the series. The degree of p,-conjugation and the molecular conformation also depend on the electronic effects of the para and meta substituents.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1525–1531, July, 1981. 相似文献
27.
S. F. Malysheva N. K. Gusarova N. A. Belogorlova A. V. Afonin S. N. Arbuzova B. A. Trofimov 《Russian Chemical Bulletin》1997,46(10):1799-1801
Diorganylvinylphosphine oxides were synthesized in 31–38% yields on heating (50°C) diorganylphosphine oxides with vinyl sulfoxides
or divinyl sulfone in the presence of KOH.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1895–1896, October, 1997. 相似文献
28.
M. F. Shostakovskii A. S. Atavin E. P. Vyalykh B. A. Trofimov N. A. Vodhol'skaya V. V. Keiko 《Russian Chemical Bulletin》1966,15(7):1239-1240
Conclusions Cyclic alkoxysilanes — 1,3-dioxa-2-silacyclanes — and their oligomers are decomposed by organomagnesium compounds with the formation of the corresponding silanols (disiloxanes) and tetraalkylsilanols.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1283–1285, July, 1966. 相似文献
29.
V.V. Nosyreva A.G. Mal'kina O.A. Shemyakina E.I. Kositsyna A.I. Albanov B.A. Trofimov 《Russian Journal of Organic Chemistry》2005,41(8):1202-1207
Nucleophilic addition of tetrazole to 4-hydroxy-4-alkyl-2-alkynonitriles and to 3-phenyl-2-propynonitrile occurred regiospecifically and afforded E-, Z-4-hydroxy-4-methyl-3-tetrazolyl-2-alkenonitriles and 3-tetrazolyl-3-phenyl-2-propenonitrile [20–40°C, 13–50 h, 4–15 wt% MOH (M = Na, K), THF (or DMSO)] in up to 69% yield. The attempt to perform cyclization of the hydroxy-containing adducts into iminodihydrofurans (KOH, ethanol, 23-25°C) resulted in vinyl nucleophilic substitution of the tetrazole moiety by an ethoxy group. 相似文献
30.
B. A. Trofimov N. K. Gusarova S. F. Malysheva S. I. Shaikhudinova N. A. Belogorlova T. I. Kazantseva B. G. Sukhov G. V. Plotnikova 《Russian Journal of General Chemistry》2005,75(5):684-688
The major product of the reaction of benzyl chloride with red phosphorus in the system concentrated aqueous KOH-dioxane-phase-transfer catalyst (43–95°C, Ar) is tribenzylphosphine oxide (yield up to 61%). Under similar conditions, phosphorylation of benzyl chloride with white phosphorus occurs differently, yielding dibenzylphosphine oxide as major product. Conditions are found for preparative synthesis of dibenzylphosphine from phosphine and benzyl chloride in the system KOH-DMSO.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 5, 2005, pp. 724–728.Original Russian Text Copyright © 2005 by Trofimov, Gusarova, Malysheva, Shaikhudinova, Belogorlova, Kazantseva, Sukhov, Plotnikova. 相似文献