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B. I. Shapiro V. M. Kazakova Ya. K. Syrkin V. M. Khutoretskii L. V. Okhlobystina 《Russian Chemical Bulletin》1969,18(2):405-407
Conclusions It was deduced that fluorine is in a -combined state in the anion radicals we studied; this was based on an analysis of the EPR spectra of a series of fluoronitroalkane anion radicals.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 458–460, February, 1969.In conclusion, the authors express their appreciation to A. A. Fainzil'berg for his interest in our work. 相似文献
14.
Dimethyl bromomethylmalonate (IV) reacts with vitamin B12s in aqueous solution yielding a relatively unstable carbon-cobalt bonded adduct V, which shows visible spectra in good accord with expectation. The adduct V was allowed to decompose in water, in the dark, at room temperature and at physiological pH. Three products: succinic acid (VI), methylmalonic acid (VIII) and malonic acid (VII) were formed in 3, 18, and 13% yields respectively. Isolation of the succinic acid rearrangement product provides support for the intermediacy of the carbon-cobalt bond in the coenzyme B12 dependent enzymic carbon-skeleton rearrangement of methylmalonyl-SCoA to succinyl-SCoA. 相似文献
15.
N. A. Turovskii S. Yu. Tselinskii I. A. Opeida Yu. E. Shapiro 《Theoretical and Experimental Chemistry》1993,28(4):254-257
A kinetic study has been made of the interaction of benzoyl peroxide with a number of chloride salts of amines. It is shown that a change of the cation in quaternary ammonium salts does not have any significant effect on the kinetic parameters of the reaction. By means of NMR spectroscopy it has been determined that the structure of the NR4
+ cation does not change during the course of the reaction. The role of the cation in the process of activation of a diacyl peroxide by chloride salts of amines has been investigated by means of MNDO calculations.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 28, No. 4, pp. 324–328, July–August, 1992. 相似文献
16.
Computationally tractable formulae for one particle differential cross sections and for coincidence cross sections for atom— diatom collision induced dissociation (CID) are obtained within the framework of first order multiple scattering theory. The first order formulation is then used to analyze the simple “knockout circle” model for CID and to derive a more reliable multiple scattering spectator model. Finally, differential and coincidence cross sections are computed for Li+ + H2 at 2O eV and are compared with experiment. The qualitative insight afforded by coincidence studies of CID is clearly demonstrated. 相似文献
17.
An increase is found in the reactivity of organomercury and organothallium nitroxyl mono- and biradicals of the imidazoline type in comparison with the analogous compounds without organometallic fragments. This is explained by the formation of coordination bonds NHg, NTl, and NOHg.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 224–226, January, 1993. 相似文献
18.
M. V. Antonova S. K. Moiseev V. N. Kalinin I. O. Shapiro 《Russian Chemical Bulletin》1989,38(11):2256-2259
Kinetic acidities of aryl and benzyl CH-bonds for complexes of benzene and its methoxy and alkyl derivatives with tricarbonylchromium are determined in a solution of lithium tert-butoxide in N,N-dimethylacetamide. Complexation of alkyl-aromatic compounds to the Cr(CO)3 group increases the lability of the aryl CH-bond by 107–109 times and that of the benzyl bond by 5·104–5·105 times. The Cr(CO)3 group in arene complexes neutralizes the effect of other substituents regardless of their nature and position in the molecule.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2458–2461, November, 1989. 相似文献
19.
Summary We show that the set
of equivalence classes of synchronously automatic structures on a geometrically finite hyperbolic groupG is dense in the product of the sets
over all maximal parabolic subgroupsP. The set
of equivalence classes of biautomatic structures onG is isomorphic to the product of the sets
over the cusps (conjugacy classes of maximal parabolic subgroups) ofG. Each maximal parabolicP is a virtually abelian group, so
and
were computed in [NS1].We show that any geometrically finite hyperbolic group has a generating set for which the full language of geodesics forG is regular. Moreover, the growth function ofG with respect to this generating set is rational. We also determine which automatic structures on such a group are equivalent to geodesic ones. Not all are, though all biautomatic structures are.Oblatum 14-VI-1993 & 4-I-1994Both authors acknowledge support from the NSF for this research. 相似文献
20.