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101.
The optical characteristics of transparent lead magnesium niobate titanate (PMNT) electro-optic ceramic, including the electro-optic phase modulation, electric hysteresis property and thermo-optic coefficient, are investigated in detail. Based on this novel ceramic, a polarization independent electro-optic switch by using fiber Sagnac interferometer (FSI) structure is realized. An initial π-shift is introduced into the Sagnac loop to eliminate the effect of the polarization orientation of the incident light on the switch performance. Then an electrically controllable PMNT phase retarder is used to switch the optical signal between the reflection and transmission ports. Some theoretical analyses are given and the switch performances are also discussed, including the thermal characteristic and different switching frequency response. 相似文献
102.
L LinHui Ye YanLin Jiang DongXing Hua Hui Zheng Tao Li ZhiHuan Ge YuCheng Li XiangQing Lou JianLing Cao ZhongXin Song YuShou Xiao Jun Li QiTe Qiao Rui You HaiBo Chen RuiJiu Xu HuShan Wang JianSong Guo ZhongYan Zhang XueYing Li Chen Hu ZhengGuo Chen RuoFu Wang Meng Xu ZhiGuo Yue Ke Tang Bin Zang YongDong Zhang XueHeng Yao XiangWu Chen JinDa Bai Zhen 《中国科学:物理学 力学 天文学(英文版)》2011,54(1):136-140
Knockout reaction experiment was carried out by using the 6He beams at 61.2 MeV/u impinging on a CH2 target. The α core fragments at forward angles were detected in coincidence with the recoiled protons at larger angles. From this exclusive measurement the valence nucleon knockout mechanism and the core knockout mechanism can be distinguished by the relation between the polar angles of the core fragments and the recoiled protons, respectively. It is demonstrated that the core knockout mechanism may result in some strong contamination to the real invariant mass spectrum.
相似文献103.
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Hong Wang Rui LiuWei Qiao Jiang Jun ZhuJian Zhi Feng Gui Fu DingXiaolin Zhao 《Applied Surface Science》2011,257(6):2203-2207
Adhesion performance of MEMS materials is increasingly important with the widely use of miniaturized devices. This paper proposed a novel method for improving adhesion performance between electrodeposited Ni multi-layers. The new method is to treat the Ni substrate in nickel chloride plating solution by pulse reverse current technique before electrodeposition. The dense oxide film of Ni substrate can be removed effectively by this electrochemical method, meanwhile, the proper roughness of Ni substrate is in favor of epitaxial growth during electrodeposition. Moreover, the Ni film is electrodeposited by the new method with low stress and coarse crystal grain. Consequently, the adhesion performance of Ni films is improved dramatically. The experimental results show that the adhesion performance of Ni film electrodeposited by the new method is about 3 times that of by traditional method. 相似文献
106.
基于有效介质理论研究了石墨烯/介质周期结构的电磁性质, 研究发现这种复合结构的等频面在太赫兹和远红外波段为双曲线, 可用来实现石墨烯基双曲色散特异材料. 通过改变石墨烯的费米能级、介质层厚度和单元结构中石墨烯的层数, 可很容易地调节双曲色散存在的频段. 由于等频面的双曲色散特性, 石墨烯基双曲色散特异材料在远低于截止频率的范围内, 对斜入射的电磁波具有负的能量折射率和正的相位折射率, 并支持局域体等离子体模式. 基于衰减全反射结构, 研究了体等离子体的激发, 探索了体等离子体在可调的光学反射调制器中的应用. 相似文献
107.
Characteristics and properties of metal aluminum thin film prepared by electron cyclotron resonance plasma-assisted atomic layer deposition technology 下载免费PDF全文
Metal aluminum (Al) thin films are prepared by 2450-MHz electron cyclotron resonance plasma-assisted atomic layer deposition on glass and p-Si substrates using trimethylaluminum as the precursor and hydrogen as the reductive gas. We focus our attention on the plasma source for thin-film preparation and annealing of as-deposited films related to the surface square resistivity. The square resistivity of as-deposited Al film is greatly reduced after annealing and almost reaches the value of bulk metal. Through chemical and structure analysis we conclude that the square resistivity is determined by neither contaminant concentration nor surface morphology, but by both crystallinity and crystal size in this process. 相似文献
108.
A dynamical equation for quantum information density (QID) in curved spacetime is presented. The related fluctuation of QID with quantum Einstein equation is also discussed, which reveals the measuring of the dynamical mutual information condition using a Gaussian quantum channel. 相似文献
109.
Baowei Qiao Jie Feng Yun Ling Ting’ao Tang Bomy Chen 《Applied Surface Science》2006,252(24):8404-8409
The effects of Si doping on the structural and electrical properties of Ge2Sb2Te5 film are studied in detail. Electrical properties and thermal stability can be improved by doping small amount of Si in the Ge2Sb2Te5 film. The addition of Si in the Ge2Sb2Te5 film results in the increase of both crystallization temperature and phase-transition temperature from face-centered cubic (fcc) phase to hexagonal (hex) phase, however, decreases the melting point slightly. The crystallization activation energy reaches a maximum at 4.1 at.% and then decreases with increasing dopant concentration. The electrical conduction activation energy increases with the dopant concentration, which may be attributed to the increase of strong covalent bonds in the film. The resistivity of Ge2Sb2Te5 film shows a significant increase with Si doping. When doping 11.8 at.% of Si in the film, the resistivity after 460 °C annealing increases from 1 to 11 mΩ cm compared to the undoped Ge2Sb2Te5 film. Current-voltage (I-V) characteristics show Si doping may increase the dynamic resistance, which is helpful to writing current reduction of phase-change random access memory. 相似文献
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