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991.
992.
993.
Singular Integrals in Several Complex Variables (I)—Henkin
Integrals of Strictly Pseudoconvex Domain
对于多复变数强拟凸域的Henkin-Ramirez核或Stein-Kerzman核所定义的Cauchy型积分,本文指出:可以有多种形式的Plemelj公式,甚至Cauchy型积分的极限值可以等于某种Cauchy主值,这些都显示了多复变数函数与单复变数函数本质上的不同。 相似文献
994.
Gong Guanglu 《数学年刊B辑(英文版)》1982,3(6):803-812
For a differential operator
$\Omega u=\sum\limits_i,j=1^n \frac{\partial}{\partial x_i}(a_ij(x)\frac{\partial u}{\partial x_j})+\sum\limits_{i=1}^n b_i(x)\frac{\partial u}{\partial x_i}+c(x)u$
with unbounded coefficients in R^n, a standard continuous paths process with infinitesimal operator \Omega has been constructed in this paper, and the invariance of such process under a transformation group of phase space has been discussed. 相似文献
995.
We report a full-dimensional study of the classical dynamics of HCN-->HNC isomerization and of HCN rovibrational dissociation driven by a strong but nonionizing picosecond infrared laser field. The dynamics of the isolated molecule and of the molecule in liquid Ar have both been studied. Our theoretical and numerical results show that when all degrees of freedom are accounted for the field induced molecular dynamics can be totally different from what was found in previous studies, where the HCN molecule is restricted to a plane containing the external field. It is shown that as HCN is driven by an infrared laser field, the rotation of the H atom around the C-N bond provides an important and highly efficient energy absorption mechanism. In the presence of a monochromatic picosecond infrared laser field with an intensity of 10(13) W/cm(2), this energy absorption mechanism generates considerable HCN-->HNC isomerization yield or high rovibrational dissociation yield without molecular preorientation or prealignment. Our study of the field induced isomerization and dissociation dynamics of the same system in liquid Ar shows that the picosecond isomerization dynamics is insignificantly affected by the surrounding atomic liquid whereas the dissociation yield may be greatly suppressed in a high density liquid. The implications of this study for full-dimensional quantum dynamics of multiphoton rovibrational excitation and dissociation of triatomics are briefly discussed. 相似文献
996.
Yuan L Sanford AR Feng W Zhang A Zhu J Zeng H Yamato K Li M Ferguson JS Gong B 《The Journal of organic chemistry》2005,70(26):10660-10669
[structures: see text] This article describes the synthetic procedures for the preparation of crescent (and helical) aromatic oligoamides developed in recent years in our laboratory. The large-scale preparation of a variety of monomers derived from various tetrasubstituted benzenes is presented. Three different strategies for constructing various oligomers consisting of meta- and meta/para-linked benzene residues are discussed. Factors affecting coupling efficiency and yields are analyzed. The developed synthetic methods have provided the basis for the preparation of longer oligomers and for the development of solid-phase synthesis. 相似文献
997.
998.
999.
Chao‐Jian Chen Gong‐Yan Liu Ye‐Ting Shi Cong‐Shan Zhu Shao‐Peng Pang Xiang‐Sheng Liu Jian Ji 《Macromolecular rapid communications》2011,32(14):1077-1081
A novel comb‐like derivative CPEG‐g‐DNQ was prepared by incorporating light responsive 2‐diazo‐1,2‐naphthoquinone (DNQ) groups into the structure of comb‐like poly(ethylene glycol) (CPEG). DLS and TEM results showed that CPEG‐g‐DNQ self‐assembled into spherical micelles with an average size of about 135 nm in water. Upon exposure to light, the micelles could be disrupted because of the conversion of hydrophobic DNQ to hydrophilic 3‐indenecarboylic acid. Additionally, hydrophobic coumarin 102 was successfully loaded into the micelles and photo‐induced ON‐OFF release was demonstrated by fluorescence spectroscopy. MTT assay revealed that the micelles are biocompatible. These photo‐responsive micelles might have great potential for controlled release of hydrophobic drugs.
1000.
基于BV理论建立基片及其上方回转椭球粒子的复合散射模型,通过矢量球谐函数展开,对散射过程进行了分析,对散射场及微分散射截面详细求解,并给出了数值计算结果,与离散源方法做了比较,同时退化为球粒子与扩展Mie理论做了比较,说明了此方法的有效性。并详细讨论分析了微分散射截面随不同入射角,散射角,回转椭球粒子的尺寸、长短轴比例,距基片的距离,介电常数,粒子取向角的变化关系。结果表明:同一散射角下入射角越大,其微分散射截面越大;粒子尺寸越大,相互作用越大,其微分散射截面越大;长短轴比例越大,其微分散射截面越小;距离基片的距离越大,微分散射截面越大;微分散射截面的变化主要依赖于相对介电常数实部、虚部数值较大的一方,并且随粒子取向角的增大而增大。 相似文献