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71.
L. D. Smirnov K. M. Dyumaev N. I. Shuikin I. F. Bel'skii 《Russian Chemical Bulletin》1962,11(12):2148-2149
Summary A new method was proposed for the synthesis of 2,4,6-trialky1-3-hydroxypyridines by the reactions of 3,5-dialkyl-2-acylfurans with ammonia. 相似文献
72.
Yu. M. Smirnov 《High Energy Chemistry》2003,37(3):129-135
The dissociative excitation of MnII spectral lines and MnCl spectral bands upon e–MnCl2 collisions was experimentally studied. Dissociative excitation is most effective for the low-lying 5
P° and 7
P° levels of MnII. Two sequences = 0 in the – systems of the MnCl molecule were detected. Possible pathways of dissociative excitation of MnII are discussed. 相似文献
73.
A. D. Smirnov 《Journal of Structural Chemistry》2003,44(5):757-762
The vibrational, rotational, and centrifugal constants have been calculated for the ground electronic states of KRb and RbCs molecules. The calculation is performed using the semiempirical potential curves constructed in a wide range of internuclear distances. The estimated spectroscopic constants are compared with experimental data. 相似文献
74.
V. G. Solomonik A. N. Smirnov M. A. Mileyev 《Russian Journal of Coordination Chemistry》2005,31(3):203-212
Molecular structure and properties of La and Lu tetrahalide ions LnX
4
–
) are studied by the configuration interaction singles-and-doubles method augmented with quadruple excitation correction (CISD+Q) and by the fourth-order Möller-Plesset perturbation theory with account for single, double, triple, and quadruple excitations (SDTQ-MP4). The atomic inner shells are described by Stevens relativistic effective core potentials. Valence basis sets are augmented with diffuse s-, p-, and polarization d-, f-, and g-functions. The equilibrium configuration of nuclei in LnX
4
–
ions was found to be tetrahedral. The equilibrium internuclear distances, quadratic force constants, vibrational frequencies, and IR intensities of LnX
4
–
ions are compared with the corresponding parameters of La and Lu trihalide molecules (LnX3), calculated within the same approximations. Regularities in the behavior of molecular parameters on going along the LnF
4
–
LnCl
4
–
LnBr
4
–
LnI
4
–
series and from La compounds to Lu compounds are revealed. Heights of the energy barriers to the LnX
4
–
inversion through the square planar structures (T
d
D
4h
T
d
) are evaluated: 100–110 and 130–150 kJ/mol for LaX
4
–
and LuX
4
–
, respectively. Enthalpies of dissociation reactions LnX
4
–
LnX3+X– are calculated and the results obtained are compared with the available experimental data.Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 3, 2005, pp. 218–228.Original Russian Text Copyright © 2005 by Solomonik, Smirnov, Mileyev.This revised version was published online in April 2005 with a corrected cover date.This revised version was published online in April 2005 with a corrected cover date. 相似文献
75.
A. M. Churakov O. Yu. Smirnov S. L. Ioffe Yu. A. Strelenko V. A. Tartakovsky 《Russian Chemical Bulletin》1994,43(9):1532-1535
2-(tert-Butyl-NNO-azoxy)aniline was prepared by selective reduction of 2-(tert-butyl-NNO-azoxy)nitrobenzene. Its bromination yielded the correspondingpara-bromo- andortho, para-dibromoanilines (3a,b).meta-Bromoanilines (6a,b) were synthesized by selective replacement of theortho-bromine atoms in ortho,para-bromo(tert-butylazoxy)benzenes (5a,b) by ammonia in toluene under pressure.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1620–1623, September, 1994.This work was carried out with the financial support of the Russian Foundation for Basic Research (Project No. 93-03-18461). 相似文献
76.
The triplet nature of rare long-lived states of d0 metallocenes formed upon ligand-to-metal energy transfer was confirmed by studies of triplet-triplet charge transfer in biscyclopentadienyl
complexes Cp2MCl2 (M = Zr (1), Hf (2)). The interaction between precatalysts and substrates of catalytic polymerization systems, viz., complexes 1 and 2 and unsaturated hydrocarbons (alkenes and dienes), was studied in the region of concentrations close to catalytic values.
For organometallic π-complexes, it has been shown for the first time that, in the case of the unsaturated hydrocarbons, the
efficiency of energy transfer obeys the Perrin equation. The process occurs at distances R
0 close to the diameter of the interacting molecules and is well described by the exchange-resonant mechanism of interaction.
In the case of the cyclopentadiene-Cp2MCl2 (M = Zr, Hf) systems, R
0 = 14.6 Å. A linear relationship between the critical radius of the quenching sphere R
0 and the number of carbon atoms in a linear α-olefin has been revealed for the first time and evidences the formation of a
π-complex between the precatalyst and substrate molecules.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 35–39, January, 2007. 相似文献
77.
The method of competing reactions is used to measure the isotope effect in styrene phenylation by iodobenzene. The kinetics of styrene, methyl acrylate, and methyl methacrylate phenylation is studied. Experimental data suggest that the step of alkene insertion is relatively fast, while the subsequent step that involves C–H bond dissociation is rate-limiting. The kinetic parameters of the process point to the dependence of the rate-limiting step of the catalytic cycle on the concentrations of base and alkene. These results are consistent with the existing hypothesis that the step of -elimination of palladium hydride is present in the mechanism. 相似文献
78.
B. S. Fedorov N. I. Golovina L. S. Barinova V. V. Arakcheeva G. V. Lagodzinskaya M. V. Loginova R. F. Trofimova V. Z. Laishev V. F. Lazarev S. P. Smirnov I. Sh. Abdrakhmanov A. I. Firkin L. O. Atovmyan 《Russian Chemical Bulletin》1992,41(12):2185-2188
1,1,4,4-Tetranitrobutane-2,3-diol reacts with formaldehyde, forming 2,2-dinitropropane-1,3-diol or a cyclic ether — 4,4-dinitro-2,3-dihydroxytetrahydrofuran — as a function of the reaction conditions.Institute of Chemical Physics, Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2755–2759, December, 1992. 相似文献
79.
Z. I. Zelikman G. N. Soltovets V. G. Kul'nevich V. A. Smirnov 《Chemistry of Heterocyclic Compounds》1971,7(4):410-411
A method was developed for the preparation of amino derivatives of 1,3-dioxanes of the furan series by amalgam reduction of the corresponding nitro compounds. This method makes it possible to obtain amino compounds without destruction of the furan and dioxane rings. 2--Aminofuryl-5-alkyl-5-methylol- and 5--aminofuryl-5,5-bis(chloromethyl)-1,3-dioxanes and their azomethines were synthesized for the first time.See [5] for communication III.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 440–442, April, 1971. 相似文献
80.
B. E. Zaitsev K. M. Dyumaev V. I. Kuz'min L. D. Smirnov 《Chemistry of Heterocyclic Compounds》1972,8(2):167-170
The IR spectra of methyl, chloro, and phenyl derivatives of 3-hydroxypyridines in CCl4 solutions and in the crystalline state were studied. A comparison of the frequencies, half widths, and integral intensities of the bands of the stretching vibrations of the hydroxyl groups in the spectra of solutions of the 3-hydroxypyridine derivatives in CCl4 with the characteristic OH bands in the spectra of phenols demonstrates that 3-hydroxypyridines exist practically completely in the hydroxy form in dilute CCl4 solutions. The shift in the OH bands in the spectra of 2-phenyl-3-hydroxypyridine derivatives indicates that the OH group forms a -hydrogen bond with the phenyl ring. The presence also of a band of a free OH group is evidence for the existence of s-cis and s-trans conformers relative to the C-O bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 187–190, February, 1972. 相似文献