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31.
Yury L. Karavaev Alexander A. Kilin Anton V. Klekovkin 《Regular and Chaotic Dynamics》2016,21(7-8):918-926
In this paper we describe the results of experimental investigations of the motion of a screwless underwater robot controlled by rotating internal rotors. We present the results of comparison of the trajectories obtained with the results of numerical simulation using the model of an ideal fluid. 相似文献
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Shou-Xin Wang Zhen Fang Zhi-Jin Fan Dun Wang Yue-Dong Li Xiao-Tian Ji Xue-Wen Hua Yun Huang Tatiana A. Kalinina Vasiliy A. Bakulev Yury Yu. Morzherin 《中国化学快报》2013,24(10):889-892
A series of novel tetrazole containing 1,2,3-thiadiazole derivatives were designed and synthesized via Ugi reaction. Their structures were confirmed by melting points, IR, 1H NMR, and HRMS (ESI). Preliminary bioassay indicated that most target compounds exhibited very good direct anti-TMV activity at 100 μg/mL, which was equal to or higher than that of ribavirin. Among them, compounds 4b, 4c and 4i also showed equivalent protection effect to ribavirin in vivo at 100 μg/mL. 相似文献
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Russian Journal of Applied Chemistry - xWO3–(100–x)P2O5 (70 mol % ≤ x ≤ 82 mol %) glasses were obtained by melt quenching. Their thermal properties were studied by the DTA... 相似文献
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On the long‐range relativistic effects in the 15N NMR chemical shifts of halogenated azines
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Dmitry O. Samultsev Yury Yu. Rusakov Leonid B. Krivdin 《Magnetic resonance in chemistry : MRC》2017,55(11):990-995
Long‐range β‐ and γ‐relativistic effects of halogens in 15N NMR chemical shifts of 20 halogenated azines (pyridines, pyrimidines, pyrazines, and 1,3,5‐triazines) are shown to be unessential for fluoro‐, chloro‐, and bromo‐derivatives (1–2 ppm in average). However, for iodocontaining compounds, β‐ and γ‐relativistic effects are important contributors to the accuracy of the 15N calculation. Taking into account long‐range relativistic effects slightly improves the agreement of calculation with experiment. Thus, mean average errors (MAE) of 15N NMR chemical shifts of the title compounds calculated at the non‐relativistic and full 4‐component relativistic levels in gas phase are accordingly 7.8 and 5.5 ppm for the range of about 150 ppm. Taking into account solvent effects within the polarizable continuum model scheme marginally improves agreement of computational results with experiment decreasing MAEs from 7.8 to 7.4 ppm and from 5.5 to 5.3 ppm at the non‐relativistic and relativistic levels, respectively. The best result (MAE: 5.3 ppm) is achieved at the 4‐component relativistic level using Keal and Tozer's KT3 functional used in combination with Dyall's relativistic basis set dyall.av3z with taking into account solvent effects within the polarizable continuum solvation model. The long‐range relativistic effects play a major role (of up to dozen of parts per million) in 15N NMR chemical shifts of halogenated nitrogen‐containing heterocycles, which is especially crucial for iodine derivatives. This effect should apparently be taken into account for practical purposes. 相似文献
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I. D. Zakir’yanova I. V. Korzun V. A. Khokhlov V. N. Dokutovich E. V. Nikolaeva B. D. Antonov 《Russian Journal of Applied Chemistry》2016,89(7):1066-1071
Data on reactivities of α- and γ-Al2O3 finely dispersed powders in a melted carbonate eutectic (Li2CO3–Na2CO3–K2CO3)eut and carbonate-chloride mixture 0.72(Li2CO3–Na2CO3–K2CO3)eut–0.28NaCl were obtained. The methods of synchronous thermal and X-ray phase analyses and Raman spectroscopy confirmed that, in contrast to γ-Al2O3, α-Al2O3 does not chemically interact with the melted carbonate eutectic and carbonate-chloride mixture (Li2CO3–Na2CO3–K2CO3)eut–NaCl can be recommended as a thickening agent for a carbonate fuel cell. 相似文献
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Yury Yu. Rusakov Irina L. Rusakova Leonid B. Krivdin 《Magnetic resonance in chemistry : MRC》2014,52(5):214-221
Four‐component relativistic calculations of 77Se–13C spin–spin coupling constants have been performed in the series of selenium heterocycles and their parent open‐chain selenides. It has been found that relativistic effects play an essential role in the selenium–carbon coupling mechanism and could result in a contribution of as much as 15–25% of the total values of the one‐bond selenium–carbon spin‐spin coupling constants. In the overall contribution of the relativistic effects to the total values of 1J(Se,C), the scalar relativistic corrections (negative in sign) by far dominate over the spin‐orbit ones (positive in sign), the latter being of less than 5%, as compared to the former (ca 20%). A combination of nonrelativistic second‐order polarization propagator approach (CC2) with the four‐component relativistic density functional theory scheme is recommended as a versatile tool for the calculation of 1J(Se,C). Solvent effects in the values of 1J(Se,C) calculated within the polarizable continuum model for the solvents with different dielectric constants (ε 2.2–78.4) are next to negligible decreasing negative 1J(Se,C) in absolute value by only about 1 Hz. The use of the locally dense basis set approach applied herewith for the calculation of 77Se–13C spin‐spin coupling constants is fully justified resulting in a dramatic decrease in computational cost with only 0.1–0.2‐Hz loss of accuracy. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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V. F. Kablov N. A. Keibal V. G. Kochetkov A. O. Motchenko Yu. M. Antonov 《Russian Journal of Applied Chemistry》2018,91(7):1160-1164
The influence of carbon microfiber on the physicomechanical, thermophysical, and fireproof characteristics of elastomeric compositions based on ethylene propylene diene rubber is considered. Microfibrous filler contributes to the manifestation of the effect of “micro-reinforcement,” which leads to an increase in the heatprotective properties of the material due to the increase in the strength of coke. The correction of microfibers with a phosphorus-boron-containing oligomer enhances the carbonization of the material, which leads to an increase in the warming-up time of the unheated sample surface by 8–10% and a decrease in the linear combustion rate by 10–15% compared to known analogues. 相似文献