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41.
Xiaohui Duan Mina Zhang Huan Du Xiu Gu Caihong Bai Liuqiang Zhang Kaixian Chen Kaifeng Hu Yiming Li 《Molecules (Basel, Switzerland)》2022,27(15)
Scrophulariae Radix (SR) is one of the oldest and most frequently used Chinese herbs for oriental medicine in China. Before clinical use, the SR should be processed using different methods after harvest, such as steaming, “sweating”, and traditional fire-drying. In order to investigate the difference in chemical constituents using different processing methods, the two-dimensional (2D) 1H-13C heteronuclear single quantum correlation (1H-13C HSQC)-based metabolomics approach was applied to extensively characterize the difference in the chemical components in the extracts of SR processed using different processing methods. In total, 20 compounds were identified as potential chemical markers that changed significantly with different steaming durations. Seven compounds can be used as potential chemical markers to differentiate processing by sweating, hot-air drying, and steaming for 4 h. These findings could elucidate the change of chemical constituents of the processed SR and provide a guide for the processing. In addition, our protocol may represent a general approach to characterizing chemical compounds of traditional Chinese medicine (TCM) and therefore might be considered as a promising approach to exploring the scientific basis of traditional processing of TCM. 相似文献
42.
由于MATLAB/Simulink本身就是一款优秀的系统建模和算法仿真工具,Modelsim是国内最为常用的HDL仿真工具,利用Link for modelsim使Modelsim与Simulink协同工作,使得算法设计和验证在同一款软件中完成。避免了不同开发环境下的兼容性问题,极大地简化了设计的复杂度,加快了开发进程。提出利用基于模型的设计方法,可以将算法与硬件实现联合起来,对于算法的开发以及后期硬件实现都会带来极大的方便。详细介绍了Modelsim与MATLAB/Simulink联合仿真的接口技术、模型的搭建,以及通过利用16 QAM调制与解调的应用实例来验证系统的正确性。 相似文献
43.
Deformed Hartree-Fock calculations are performed for some light nuclei in a large configuration space consisting of first
four major shells. The interaction employed is the modified Skyrme interaction in which the deformed density is replaced by
the band averaged scalar density that makes the Hamiltonian rotationally invariant rendering the spectroscopic calculations
feasible. It is shown that the introduction of density dependence spreads out the energy spectra and that the Skyrme variant
SIV which has a weak density dependence gives best overall agreement for energy spectra and the available data for the electromagnetic
properties of the nuclei studied. It is found that the maximum contribution to the energy of any state in the low lying spectrum
comes from thes-state attractive ands-state repulsive parts of the Skyrme interaction. It is also shown that when two-body density dependent version of Skyrme
interaction is used, the Koopmans theorem no longer holds. 相似文献
44.
Alexey Sulimov Danil Kutov Ivan Ilin Yibei Xiao Sheng Jiang Vladimir Sulimov 《Molecules (Basel, Switzerland)》2022,27(9)
The COVID-19 pandemic is still affecting many people worldwide and causing a heavy burden to global health. To eliminate the disease, SARS-CoV-2, the virus responsible for the pandemic, can be targeted in several ways. One of them is to inhibit the 2′-O-methyltransferase (nsp16) enzyme that is crucial for effective translation of viral RNA and virus replication. For methylation of substrates, nsp16 utilizes S-adenosyl methionine (SAM). Binding of a small molecule in the protein site where SAM binds can disrupt the synthesis of viral proteins and, as a result, the replication of the virus. Here, we performed high-throughput docking into the SAM-binding site of nsp16 for almost 40 thousand structures, prepared for compounds from three libraries: Enamine Coronavirus Library, Enamine Nucleoside Mimetics Library, and Chemdiv Nucleoside Analogue Library. For the top scoring ligands, semi-empirical quantum-chemical calculations were performed, to better estimate protein–ligand binding enthalpy. Relying upon the calculated binding energies and predicted docking poses, we selected 21 compounds for experimental testing. 相似文献
45.
46.
Stephen D. Pastor David N. Rahni Nancy Khoury Stephen A. Koch 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1951-1956
The X-ray crystallographic analysis of 6,6-dimethyl-2,4,8,10-tetra-tert-octyl-dibenzo[d,f][1,3,2]dioxagermepin, 1 is reported. In the solid-state conformation of 1, the dihedral angle about the C─C sp2-sp 2 σ bond connecting the two aryl rings is 50.1°. The observed C2 symmetry in the solid-state conformation of 1 is consistent with the previously suggested solution conformation. 相似文献
47.
B.V. Rathish Kumar 《International Journal of Computational Fluid Dynamics》2013,27(2):101-111
In this study, parallel computation of unsteady incompressible flow in an asymmetrically constricted 3D vessel has been presented. A time accurate cell centered finite volume method (FVM) in conjunction with pseudo-compressibility technique and Roe's flux difference splitting of nonlinear terms has been employed for solving the Navier-Stokes (NS) equations on the multiple instruction multiple data (MIMD) machine VPP700. The influence of Reynolds' number ( Re ) and the Strouhal number ( St ) on flow dynamic factors like wall pressure (WP), wall shear stress (WSS), central axis velocity (CAV), etc., have been analyzed. Three-dimensional (3D) features in the formation and detachment of separation zones, which are sensitive to both Re and St have been noticed on the diverging wall of the constriction. 相似文献
48.
Michal Firstenberg Kammasandra Nanjunda Shivananda Irit Cohen Olga Solomeshch Vladislav Medvedev Nir Tessler Yoav Eichen 《Advanced functional materials》2011,21(4):634-643
Sequence‐independent or “click”‐type chemistry is applied for the preparation of novel π‐conjugated oligomers. A variety of bi‐functional monomers for Wittig–Horner olefination are developed and applied in a sequential protection–deprotection process for the preparation of structurally similar π‐conjugated oligomers. Selected oligomers are incorporated as the organic semiconductors in light‐emitting diodes and a field‐effect transistor, demonstrating the potential of the approach. 相似文献
49.
Ronald G. Larson 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2012,124(11):2596-2598
50.
在s波超导体绝缘层dx2-y2波超导体结(sId)中,考虑到结界面粗糙散射,运用BogoliubovdeGennes(BdG)方程和FurusakiTsukada(FT)电流公式,计算超导结中的准粒子传输系数和直流Josephson电流.结果表明:sId超导结的直流Josephson电流随温度以及结两侧的相位差变化的关系曲线强烈地依赖于d波超导体的晶轴方位;结界面的粗糙散射对Josephson电流有抑制作用
关键词:
s/I/d超导结
dx2-y2波超导体
直流Josephson电流 相似文献