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991.
V. A. Khitrov C. Panteleev A. M. Sukhovoj J. Honzátko I. Tomandl 《Physics of Atomic Nuclei》2004,67(10):1818-1822
Main properties of the excited states of 118Sn manifesting themselves in cascade γ decay of its compound state are studied. As in heavier nuclei studied earlier, qualitative interpretation of the whole set
of observed properties of the nucleus appears to be impossible without accounting for coexistence and interaction of quasiparticle
and collective nuclear excitations and their considerable influence on the main parameters of the process under study.
From Yadernaya Fizika, Vol. 67, No. 10, 2004, pp. 1845–1849.
Original English Text Copyright ? 2004 by Khitrov, Panteleev, Sukhovoj, Honzátko, Tomandl.
This article was submitted by the authors in English. 相似文献
992.
研究了非相干辐照对LiNbO3:Fe晶体中从自散焦到自聚焦的动态转换过程的影响和控制作用.无论是从前向还是从背向加入非相干辐照,都能加快自散焦、自聚焦过程以及从自散焦到自聚焦的转换过程,增大折射率的变化值.当非相干辐照以一定的时间间隔重复辐照在晶体上时,透射功率能迅速地上升和下降,具有明显的开关效应.这种在非相干辐照控制下折射率的迅速改变有望应用于全光学开关器件.
关键词:
非相干辐照
光伏效应
自散焦
自聚焦 相似文献
993.
994.
995.
V. K. Voronkova R. T. Galeev S. Shova G. Novitchi C. I. Turta A. Caneschi D. Gatteschi J. Lipkowski Yu. A. Simonov 《Applied magnetic resonance》2003,25(2):227-247
New compounds, [Cu3Ln2(ClCH2COO)12(H2O)8]·2H2O with Ln = Nd3+ (I), Sm3+ (II), Pr3+ (III), built up of pentanuclear clusters were synthesized and studied by means of X-ray analysis and electron paramagnetic
resonance (EPR). X-ray data show that all compounds are isostructural and the pentanuclear clusteres may be considered as
a linear system with alternating Cu(II) and Ln(III) ions: Cu(2)-L1-Ln-L2-Cu(1)-L2-Ln-L2-Cu(2) with L1 and L2 being bridging fragments and Cu(1) and Cu(2) being structurally nonequivalent copper complexes. EPR studies demonstrate that
in the temperature range of 100–293 K the signals due to only one type of the copper complexes are observed in the spectra
of I–III. AtT<100 K the spectral temperature dependence is nontrivial. AtT<30 K new signals are detected in the spectra of I and II. The temperature dependence of the EPR spectra is interpreted under
the assumption that the parameter of the exchange interaction Cu(2)-Ln considerably exceeds the parameter of the interaction
Cu(1)-Ln. EPR spectra are calculated for the fragments of five paramagnetic centers in the frames of the model taking into
account the nonequivalence of two copper complexes, short longitudinal and transverse paramagnetic relaxation times of the
rare-earth ions at room temperature and the change of the relaxation rates when the temperature decreases. The results of
the calculations show that it is possible to obtain information about the interactions in the system on the basis of the analysis
of the temperature dependence of the EPR spectra of the central copper complex. The parameter of the isotropic part of the
exchange interaction between copper and neodymium ions (for the interaction Cu(2)-Nd) is estimated as about 15 cm−1. A considerable rearrangement of the spin states when the temperature changes is found for all complexes. 相似文献
996.
We report on Raman scattering of VO2 films prepared by radio frequency magnetron sputtering under different conditions. Our investigations revealed that the dominated Raman peaks shift towards high frequency for both V-rich and O-rich VO2 films, compared with the stoichiometry VO2 films. The experimental evidence is presented and the cause for nonstoichiometry dependence of Raman spectra of VO2 films is discussed. 相似文献
997.
Hydrogenated amorphous GaP films have been prepared by reactive rf sputtering. Infrared spectroscopy, optical transmission and reflection, photothermal deflection spectroscopy and dc conductivity have been studied to investigate the local bonding configurations, the optical absorption edges and the temperature dependence of the conductivity as a function of hydrogen content. The results are discussed and compared with the effects of hydrogenation on amorphous Si. 相似文献
998.
设G是有限群,|G|-1∈R.本文证明了与强G-分次环R,R#k[G]*,非分次R-模和Re-模有关的两个Maschke-型定理. 相似文献
999.
1000.
采用PM 3半经验方法对肾上腺素和二甲亚砜与肾上腺素形成的 1∶1复合物的结构进行了几何优化 .在此基础上用密度泛函理论 (DFT)的B3LYP方法 ,分别在 6 31G、6 31G 、6 31+G 基组水平上进行了精确计算 ,并通过单点能计算考察了它们之间在形成各种复合物前后的能量和分子结构参数变化特点 .在各基组水平上所有物种的能量均进行零点振动能 (ZPVE)校正 .计算结果表明 ,二甲亚砜与肾上腺素能形成 6种稳定的复合物 ,在这些复合物中都具有较强的氢键作用 .计算结果能够解释有关实验现象 相似文献