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21.
Synthesis and nitration of NH- and N-vinyl-4,5,7-trimethyl-4,5,6,7-tetrahydropyrrolo[3,2-c]pyridines
T. N. Borisova I. A. Stazharova A. É. Aliev N. S. Prostakov A. V. Varlamov 《Chemistry of Heterocyclic Compounds》1991,27(10):1105-1109
It has been shown that the most efficient catalysts for the synthesis of 4,5,7-trimethyl-4,5,6,7-tetrahydropyrrolo[3,2-c]pyridine from 1,2,5-trimethylpyridin-4-one and acetylene under Trofimov conditions are rubidium and potassium hydroxides. Use of Triton B or a mixture of trimethylbenzylammonium chloride with rubidium hydroxide as catalyst gives O-alkylated oxime. Their configurations and conformations were established through separation of the individual isomers of 1-vinyl-4,5,7-trimethyl-4,5,6,7-tetrahydropyrrolo[3,2-c]pyridines. Acetyl nitrate nitration of the cis isomer of this compound gave the 2- and 3-nitro derivatives. Similar nitration of 4,5,7-trimethyl-4,5,6,7-tetrahydropyrrolo[3,2-c]pyridine gave the 2-nitro-7-hydroxy derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1375–1380, October, 1991. 相似文献
22.
23.
In the quark-parton model we obtain an expression for the effective cross section of the process of direct photon generation in the annihilation of an antineutrino and an electron into hadrons (e + e + X). The angular and energy dependences of the photons are investigated. It is shown that for large photon energies, the contribution from hadronic radiation dominates that from leptonic radiation.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 98–103, November, 1987. 相似文献
24.
25.
V. V. Davydov B. E. Zaitsev M. G. Sarabia A. É. Aliev G. V. Sheban V. L. Savel'ev V. S. Troitskaya 《Chemistry of Heterocyclic Compounds》1990,26(11):1258-1264
The structure of the previously synthesized 1,2-dihydro-3-(2-hydroxyphenyl)-4-nitropyrazol-5(3H)-one (I) was studied by 1H and 13C NMR, IR, and electronic spectra. It was established that the NMR spectra of compound (I) do not contain signals for the H atom at position 4 and the C atoms of the carbonyl groups; in the crystalline state and in solutions the IR spectra do not contain vc=o bands, while the electronic spectra do not contain absorption in the region of 250 nm. On the basis of the foregoing it is concluded that compound (I) exists in the OH form. The distribution of -electron density in the molecule of (I) and the nature of the bands in its electronic absorption spectrum were studied by quantum-chemical methods in the PPP approximation.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1510–1516, November, 1990. 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.
Thiophenols add to 1-vinyl-4,5,6,7-tetrahydroindole and 1-vinyl-2-phenylpyrrole in the presence of azobisisobutyronitrile to form 1-(2-arylthioethyl)pyrroles. The major products in the absence of initiator are the isomeric 1-(1-arylthioethyl)pyrrole -adducts. NH-Pyrroles inhibit the radical process and form selectively the -adducts.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 750–752, June, 1990. 相似文献
28.
A new method for heat exchange between dispersed flows and a unit for continuous selective heating, comprising a heater and a mass-exchange apparatus, was proposed. A mathematical model of the unit was developed for the cases of direct-flow and counterflow heaters. Analytical solutions to the model equations were obtained. The parameters affecting the result of continuous selective heating of the dispersion medium in the unit were determined. 相似文献
29.
E. L. Gaidarova K. Rosher A. É. Aliev G. V. Grishina 《Chemistry of Heterocyclic Compounds》1992,28(10):1175-1178
Enantiomericalfy pure (–)-(10S)-6,10-dimethyl-6-am-1,9-octahydroquinoline, which has been obtained from optically pure (3S)-1,3-dimethyl-3-(2-cyanoethyl)piperid-4-one, is a chiral intermediate for the preparation of novel biologically active compounds and an analog of piperidine and decahydroquinoline alkaloids. The chiroptical properties of the synthesized 6-azaoctahydroquinoline are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1379–1383, October, 1992. 相似文献
30.
R. G. Aflyatunova N. A. Aliev Ch. Sh. Kadyrov M. R. Yagudaev 《Chemistry of Natural Compounds》1984,19(4):478-482
The reactions of benzoxazolinone and benzoxazolinethione with alkyl -chlorovinyl ketones have been studied. The reaction products are N-(-acylvinyl)benzoxazolinones and N-(-acylvinyl)benzoxazolinethiones. The reaction of alkali-metal salts of benzoxazolinone with alkyl -chlorovinyl ketones leads to the opening of the oxazolinone ring. The structures of the compounds synthesized have been studied by IR, mass, and PMR spectroscopy.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 507–511, July–August, 1983. 相似文献