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51.
The wave functions of donor–acceptor pairs before and after electron transfer are written as a product of the electron-vibrational wave functions of the donor and acceptor with allowance for the change in the number of electrons on these particles by one after transition. In this approximation, the energy of the initial state is represented as a sum of the electron-vibrational levels of the donor and acceptor and that of the final state as a sum of donor cation and acceptor anion levels. Formulas for the electron transfer probability of symmetrical and nonsymmetrical donor–acceptor pairs have been derived that express the dependence of this process on the ionization potential difference of the donor and the electron affinity of the acceptor, on the vibrational frequencies of these particles, and on temperature. 相似文献
52.
S. V. Volkov S. V. Kutyakov A. N. Levov E. I. Polyakova Le Tuan An S. A. Soldatova P. B. Terentiev A. T. Soldatenkov 《Chemistry of Heterocyclic Compounds》2007,43(10):1260-1268
It has been established that on heating, 3-benzoyl-4-hydroxy-1-methyl-4-phenylpiperidine is ring-opened in the presence of
arylamines by a type of retroaldol reaction, with subsequent transamination of the intermediate Mannich base and the formation
of 3-arylamino-1-oxo-1-phenylpropanes. When using arylhydrazines this γ-piperidol is recyclized with the formation of 1,3-diarylpyrazoles
and their 4,5-dihydro derivatives. The mass spectral behavior of a series of 3-arylamino-substituted 1-phenylpropanones has
been studied.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1486–1495, October, 2007. 相似文献
53.
V. M. Govorun V. E. Tretiakov N. N. Tulyakov V. B. Fleurov A. I. Demin A. Yu. Volkov V. A. Batanov A. B. Kapitanov 《International Journal of Infrared and Millimeter Waves》1991,12(12):1469-1474
This paper describes the effect of far-infrared radiation on the activity and secondary structure of albumin, alcohol dehydrogenase, peroxidase and trypsin. For the first time the data obtained allowed a conclusion that enzymatic activity changes under the influence of radiation having the wavelength of 90 m. No disruptures of polypeptide chains or oligomerization of proteins were obtained. It has been shown that albumin secondary structure calculated from circular dichroism spectra changes lineary according to dose of laser emission.Abbreviations FIR
far-infarred radiation
- CD
circular dichroism
- ADG
alcohol dehydrohenase
- PXD
peroxidase
- ANS
1-anilinenaphalene-8-sulfonic acid 相似文献
54.
V. V. Volkov E. A. Iliinchik B. A. Kolesov V. N. Ikorskii O. V. Volkov 《Journal of Structural Chemistry》1996,37(6):897-905
The results of the spectral and magnetochemical studies of some salts of the “sandwich-like” paramagnetic anion {NiIII[η5-π-(3)-1,2-B9C2H11]2}– (I) with the Cs+, (CH3)4N+, and (C6H5)4P+ cations and the cation complex of Fe(II) and 1,10-phenanthroline, [FeIIPhen3]2+, are reported. The solid-phase IR, Raman, and X-ray photoelectron spectroscopy methods and optical spectroscopy of solutions
were used. The effective magnetic moments (μeff) of Ni(III) in anion (I) were measured by the Faraday technique and corrected for the diamagnetism of the aromatic cluster
ligands 1,2-B9C2H
11
2−
(II). It is established that μeff is weakly dependent on the nature of the cation. The problems concerned with the nature of the metal-ligand bonds in metal-carborane
systems like (I) are discussed. The hypothesis of the charge transfer from ligands (II) to the transition metal atoms is validated,
the donor ability rows of the π-ligands are introduced, and the cluster structure of the systems under study is attested.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 6, pp. 1060–1071, November–December, 1996.
Translated by I. Izvekova 相似文献
55.
Preparation and characterization of the first derivatives of the fused macropolyhedral anion [B22H22]2− are reported. The species [B22H21OH]2− (1) and [B22H21OEt]2− (2) are obtained from workup of the products of the reaction between HgBr2 and [NBzlEt3]2[B22H22]; a cluster involving the conjoining of a closo-B12 icosahedron with a nido-B10 cluster. Washing the products with ethanol followed by thin-layer chromatography allows the isolation of 1 and 2, reproducibly, in yields of 27 and 20%, respectively. The species were characterized by NMR spectroscopy, elemental analysis and X-ray diffraction studies. The crystal structure determinations of the two species identify novel features. Apparently the influence of the O atoms in the ions [B22H21OH]2− and [B22H21OEt]2− results in the lengthening of what was a gunwale B---B connection adjacent to the junction of the two cages such that the distances are 2.180 and 2.230 Å, respectively. These latter are longer than the corresponding distance in the parent species [B22H22]2−, which is 2.09 Å; quite long for a normal B---B distance. Thus it is assumed that these B atoms, in 1 and 2, one of which bears the substituent, are not bonded to each other. 相似文献
56.
M. I. Volkova-Gugeshashvili A. G. Volkov V. S. Markin 《Russian Journal of Electrochemistry》2006,42(10):1073-1078
The thermodynamics of adsorption of amphiphilic surface-active compounds at the interface between two immiscible liquids is
considered. At the interface, these molecules are supposed to replace a few of the adsorbed molecules of both solvents. Classical
isotherms of adsorption (Frumkin, Frumkin-Damaskin, Langmuir, Henry) were based on the model of non-penetrable interface,
where an adsorbate can substitute only molecules of one solvent. At the interface between two immiscible electrolytes, nonpolar
oil/water interfaces, and liquid membranes amphiphilic molecules can substitute molecules of both solvent and classic isotherms
cannot be used. The generalization of Frumkin isotherm for permeable and non-permeable interfaces, known as the Markin-Volkov
isotherm, gives the possibility to analyze adsorption in a general case. The adsorption isotherms of pentafluorobenzoic acid
at the octane/water interface at different pHs were measured by the drop-weight method. The thermodynamic parameters of pentafluorobenzoic
acid (PFBA) adsorption at octane/water interface were determined. From the measurements of PFBA adsorption, the structure
of the octane/water interface was determined. Substitution of one adsorbed octane molecule requires approximately three adsorbed
PFBA molecules. This result shows that the orientation of solvent molecules at the interface is different from the bulk. Adsorbed
octane molecules have a lateral orientation with respect to the interface. Gibbs free energy of adsorption equilibrium and
thermodynamic parameters of PFBA adsorption show that the adsorption of PFBA at the octane/water interface is accompanied
by a reduction in the attraction between adsorbed PFBA molecules as the pH decreases to the acidic region.
Published in Russian in Elektrokhimiya, 2006, Vol. 42, No. 10, pp. 1194–1200.
The text was submitted by the authors in English. 相似文献
57.
58.
E. Ardashev V. Avdeichikov V. Balandin G. Bogdanova V. Dunin O. Gavrishchuk V. Golovkin S. Golovnya S. Gorokhov A. Isupov A. Kazakov A. Kholodenko A. Kiryakov E. Kokoulina A. Kutov N. Kuzmin I. Lobanov V. Nikitin Yu. Petukhov G. Pokatashkin M. Polkovnikov V. Popov S. Reznikov V. Rogov V. Ronzhin I. A. Rufanov V. Ryadovikov Yu. Tsyupa V. Volkov A. Vorobiev N. Zhidkov L. Zolin 《The European Physical Journal A - Hadrons and Nuclei》2016,52(8):261
59.
Recent measurements of the conductivity of nanoperforated graphene are interpreted in terms of edges states existing near the edge of each nanohole. The perimetric quantization of edge states should result in the formation of a quasi-equidistant ladder of quasistationary energy levels. Dirac fermions filling this ladder rotate about each nanohole in the direction determined by the valley index. It is shown that the irradiation of this system by circularly polarized terahertz radiation leads to a resonance in absorption in one of the valleys. The magnitude of absorption at the resonance frequency can be controlled by means of gate voltage. 相似文献
60.