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101.
Three‐Dimensional Multilayer Assemblies of MoS2/Reduced Graphene Oxide for High‐Performance Lithium Ion Batteries 下载免费PDF全文
Geng Liu Yiyu Feng Yu Li Mengmeng Qin Haoran An Wenping Hu Wei Feng 《Particle & Particle Systems Characterization》2015,32(4):489-497
Three‐dimensional (3D) multilayer molybdenum disulfide (MoS2)/reduced graphene oxide (RGO) nanocomposites are prepared by a solution‐processed self‐assembly based on the interaction using different sizes of MoS2 and GO nanosheets followed by in situ chemical reduction. 3D multilayer assemblies with MoS2 wrapped by large RGO nanosheets and good interface are observed by transmission electron microscopy. The interaction of Na+ ions with oxygen‐containing groups of GO is also investigated. The measurement of lithium ion batteries (LIBs) shows that MoS2/RGO anode nanocomposite with a weight ratio of MoS2 to GO of 3:1 exhibits an excellent rate performance of 750 mAh g?1 at 3 A g?1 outperforming many previous studies and a high reversible capacity up to ≈1180 mAh g?1 after 80 cycles at 100 mA g?1. Good rate performance and high capacity of MoS2/RGO with 3D unique layered‐structures are attributed to the combined effects of continuous conductive networks of RGO, good interface facilitating charge transfer, and strong RGO sheets preventing the volume expansion. Results indicate that 3D multilayer MoS2/RGO prepared by a facile solution‐processed assembly can be developed to be an excellent nanoarchitecture for high‐performance LIBs. 相似文献
102.
Wireless Networks - In this paper, we investigate the impacts of mobility on the characterization of energy consumption in wireless networks. Considering a linear wireless network deployed for an... 相似文献
103.
Xiao Qi Feng Jinrong Feng Mengmeng Li Jiawen Liu Yi Wang Dan Huang Shan 《Mikrochimica acta》2019,186(7):1-9
Microchimica Acta - A self-sacrificing catalytic method is described for the preparation of magnetic core/dual-functional-shell nanocomposites composed of magnetite, gold and Prussian blue (type... 相似文献
104.
以PbCl2为介质, 采用无电沉积方法制备了掺钯碳纳米管, 并对其形貌和结构进行了表征. 结果表明, 掺入的钯纳米粒子分布均匀、 粒径均一, 掺杂量与粒径尺寸适中; 所掺入的纳米粒子的成分为0价态的钯, 且掺杂类型为p型. 电接触性能测试结果表明, 掺钯碳纳米管与金电极间的接触电阻得到了明显改善, 阻值平均降幅高达近71.09%. 相似文献
105.
Pin Gao Yanfang Zhang Guangsu Huang Mengmeng Chen Jing Zheng 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):142-147
The multi-hydroxymethyl structure of resol makes it suitable for connecting two or more polyacrylamide chains as a crosslinker in oil recovery applications, but control of the structure and composition of the resol, whether in practice or theory, is still a controversial problem. In the present research, a series of resol prepolymers synthesized with different amounts and types of catalysts, formaldehyde to phenol molar ratio, reaction temperature and charging steps were characterized by high-performance liquid chromatography. It is found that the compositions of the resols barely changed with almost all the varying conditions, but the contents of each component were greatly affected by the variation of reaction conditions. Finally, the best conditions for preparing resol crosslinker were obtained. 相似文献
106.
107.
Andrei V. Churakov Elmira Kh. Lermontova Kirill V. Zaitsev Mengmeng Huang Sergey S. Karlov Galina S. Zaitseva Judith A. K. Howard 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(11):o587-o592
Four distinct hydrogen‐bonding topologies were observed in the structures of six diethanolamine ligands. These compounds are (1R*,2R*)‐2‐[(2‐hydroxyethyl)(methyl)amino]‐1,2‐diphenylethanol, C17H21NO2, (I), 1‐[(2S)‐2‐(hydroxydiphenylmethyl)pyrrolidin‐1‐yl]‐2‐methylpropan‐2‐ol, C21H27NO2, (II), 2‐[(2‐hydroxyethyl)(methyl)amino]‐1,1‐diphenylethanol, C17H21NO2, (III), 1‐{(2‐hydroxy‐2‐methylpropyl)[(1S)‐1‐phenylethyl]amino}‐2‐methylpropan‐2‐ol, C16H27NO2, (IV), 1‐{[(2R)‐2‐hydroxy‐2‐phenylethyl][(1S)‐1‐phenylethyl]amino}‐2‐methylpropan‐2‐ol, C20H27NO2, (V), and (1R*,2S*)‐2‐[(2‐hydroxyethyl)(methyl)amino]‐1,2‐diphenylethanol, C17H21NO2, (VI). In each compound, all `active' hydroxy H atoms are engaged in hydrogen bonding, but the N atoms are not involved in intermolecular hydrogen bonding. In the structures of (I), (II) and (IV)–(VI), molecules are linked into chains by intermolecular O—H...O interactions. These chains are organized in such a way as to hide the hydrophilic groups inside, and so the outer surfaces of the chains are hydrophobic. The structure of (VI) contains two distinct non‐equivalent systems of intermolecular O—H...O hydrogen bonds formed by disordered hydroxy H atoms. 相似文献
108.
109.
AbstractIn Dedekind-finite ring, we present the group inverse of sum of two group invertible elements under different conditions. Then, the core inverse of a sum of two core invertible elements is investigated. Furthermore, the core inverse of the difference of two core invertible elements is presented. These results generalized the corresponding results of complex matrices. 相似文献
110.
H. Mengmeng S. S. Karlov M. V. Zabalov K. V. Zaitsev D. A. Lemenovskii G. S. Zaitseva 《Russian Chemical Bulletin》2009,58(8):1576-1580
Geometries of 20 germylenes and 18 stannylenes based on dialkanolamines, diethylenetriamines, and related compounds were optimized
by the DFT method. It was found that the most of the germylenes and stannylenes studied are more stable as dimeric structures
of different types. The dimerization is possible due to either additional Ge-O(N) interactions or Ge-Ge bonding. The factors
leading to the stabilzation of one or another isomer are examined. 相似文献