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71.
M. A. Khodorkovskii A. A. Belyaeva L. P. Rakcheeva P. Yu. Serdobintsev A. S. Melnikov I. A. Shevkunov N. A. Timofeev A. A. Pastor 《Optics and Spectroscopy》2012,112(5):679-695
Electronic spectra of the Xe2 molecules in the energy range of 77700?C89300 cm?1 are recorded. The method of resonance enhanced multiphoton ionization of molecules in a supersonic molecular beam was used, in which excitation of the molecules by three photons was followed by ionization caused by a fourth photon (the (3+1) REMPI method). Analysis of the vibrational structure of observed systems of bands yielded information about the dissociation energy and the molecular constants for ungerade states of molecules. On the basis of the Franck-Condon principle, the equilibrium distances for potential curves were estimated from the relative intensities in vibrational progressions. Data on 16 new electronic states of diatomic xenon molecules with the dissociation limits Xe 2 * ?? XE(5p 6 1 S 0) + Xe*(5p 56p,5d, 7s, 7p) were obtained. 相似文献
72.
Viacheslav I. Tsirelnikov Boris V. Lokshin Prof. Dr. Petr Melnikov Valter A. Nascimento 《无机化学与普通化学杂志》2012,638(14):2335-2339
The dependence of the gallium trichloride saturated and unsaturated vapor pressures on temperature was studied by the static method using a quartz membrane zero‐manometer and taking into account the volume of its working chamber and substance mass. Conclusions about the presence of a distinguishable amount of trimeric molecules along with dimeric and momomeric molecules in the vapor were drawn on the basis of the obtained data. The following rough thermodynamic characteristics of a gaseous trimer of gallium trichloride were calculated: ΔfH° (Ga3Cl9, gas, 298 K) = –1466 kJ · mol–1. S°(Ga3Cl9, gas, 298 K) = 654 J · mol–1 · K–1. These data were used to elucidate the composition of the gaseous phase at a total pressure of 1 atm in the temperature range of 400–750 K. The suggested existence of trimeric molecules was not contradicted by vibrational spectroscopic analysis of gallium trichloride saturated vapor. 相似文献
73.
Faustova M. R. Nikolskaya E. D. Zhunina O. A. Mollaev M. D. Yabbarov N. G. Lobanov A. V. Melnikov M. Ya. Severin E. S. 《Russian Chemical Bulletin》2018,67(2):359-365
Russian Chemical Bulletin - In order to study the possibility of using a metal complex of the porphyrin series, FeIIICl-tetraphenylporphyrin (FeClTPP), and its polymeric form as antitumor agents... 相似文献
74.
Paradezhenko G. V. Melnikov N. B. Reser B. I. 《Computational Mathematics and Mathematical Physics》2020,60(3):404-410
Computational Mathematics and Mathematical Physics - We propose a numerical continuation method for a nonlinear system that consists of scalar and functional equations. At each parameter step, we... 相似文献
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77.
S. V. Chervon V. N. Melnikov A. A. Starobinsky 《General Relativity and Gravitation》2004,36(7):1509-1511
78.
The three-body quantum scattering problem reduced by the expansion of the wavefunction over the specially constructed basis to a two-body problem is considered. The asymptotics of this basis, as well as the solutions of the effective two-body equations are derived. A total S-matrix for 2 (2, 3) processes is expressed in terms of adiabatic amplitudes and vice versa. 相似文献
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80.
Ring Opening of Donor–Acceptor Cyclopropanes with the Azide Ion: A Tool for Construction of N‐Heterocycles
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Konstantin L. Ivanov Dr. Elena V. Villemson Dr. Ekaterina M. Budynina Dr. Olga A. Ivanova Dr. Igor V. Trushkov Prof. Mikhail Ya. Melnikov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):4975-4987
A general method for ring opening of various donor–acceptor cyclopropanes with the azide ion through an SN2‐like reaction has been developed. This highly regioselective and stereospecific process proceeds through nucleophilic attack on the more‐substituted C2 atom of a cyclopropane with complete inversion of configuration at this center. Results of DFT calculations support the SN2 mechanism and demonstrate good qualitative correlation between the relative experimental reactivity of cyclopropanes and the calculated energy barriers. The reaction provides a straightforward approach to a variety of polyfunctional azides in up to 91 % yield. The high synthetic utility of these azides and the possibilities of their involvement in diversity‐oriented synthesis were demonstrated by the developed multipath strategy of their transformations into five‐, six‐, and seven‐membered N‐heterocycles, as well as complex annulated compounds, including natural products and medicines such as (?)‐nicotine and atorvastatin. 相似文献