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81.
有机薄膜器件负电阻特性的影响因素 总被引:1,自引:1,他引:0
研究了影响有机染料掺杂聚合物薄膜器件负电阻特性的因素,为探索有机负电阻的机理提供实验依据。实验中制备了多种有机染料掺杂聚合物薄膜器件,研究了有机小分子染料、聚合物基体、薄膜组成及厚度、ITO和聚苯胺阳极等对有机染料掺杂聚合物薄膜器件负电阻特性的影响。在室温、大气环境下,所制备的多种有机染料掺杂聚合物器件在所加电压为3~4V时,观察到明显的负电阻特性,电流峰谷比最大约为8。负电阻现象及峰谷比的大小受膜厚和器件的结构、制备工艺等影响。提出用负电阻和二极管并联组成的等效电路模型解释影响负电阻特性的因素,认为负电阻特性与载流子的不平衡注入有关。在此基础上设计、合成了主链含唔二唑电子传输基团的可溶性聚对苯撑乙烯衍生物,该聚合物兼具空穴和电子传输功能,在空气中具有较稳定的N型负电阻特性。进一步控制相关材料和工艺条件,有可能得到易于控制的负阻效应,开发出新型的有机负电阻器件。 相似文献
82.
C. Bréchignac Ph. Cahuzac F. Carlier C. Colliex M. de Frutos N. Kébaïli J. Le Roux A. Masson B. Yoon 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):265-268
We studied shape relaxation of nano-fractal islands,
during annealing, after their growth from antimony cluster
deposition on graphite surface. Annealing at
180°C shows evidence of an increase
of the fractal branch width with time followed by branch
fragmentation, without changing the fractal dimension. The time
evolution of the width of the arm suggests the surface
self-diffusion mechanism as the main relaxation process. With
Monte Carlo simulations, we confirmed the observed behavior.
Comparison is done with our previous results on fragmentation of
nano-fractal silver islands when impurity added to the incident
cluster promotes rapid fragmentation by surface self-diffusion
enhancement [1]. 相似文献
83.
E. S. Dy H. Kasai 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(2):241-245
We study the interaction between tin(II) porphyrin (SnPor) with platinum and
non-precious Group 8B metals (iron, cobalt and nickel) by density functional
theory and discuss the electronic properties of the resulting products. We
also model the interaction of the resulting compounds with water where
applicable. Our studies indicate that, SnPor-Ni possesses electronic
properties similar to SnPor-Pt, suggesting that it may possess similar
photocatalytic properties for reduction reactions, such as converting water
to hydrogen gas. 相似文献
84.
85.
This work reports a new synthetic approach for single‐phase TiO2 nanomaterials by solvothermal treatment of titanium tetrachloride in acetone at 80–110 °C. Small, uniform, and yet size‐tunable (5–10 nm) anatase titania nanocrystallites were obtained using a low concentration of TiCl4 in acetone (i.e., at molar ratios of TiCl4/acetone ≤ 1:15) in the temperature range of 80–110 °C, while rutile nanofibers were synthesized using a high concentration of TiCl4 (e.g., TiCl4/acetone = 1:10) at 110 °C. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
86.
在研究排队网络的文献中,G-网络(即推广的排队网络)最近受到了国际学者广泛的关注,它的研究在一定程度上丰富了排队网络的内容.正因为有很多学者投入到此项研究中,新的结果是层出不穷的.本文简短地介绍G-网络近年来的发展. 相似文献
87.
88.
Effects of Nb2O5 on thermal stability and optical properties of Er3+-doped tellurite glasses
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Er3+-doped tellurite glasses with molar compositions of
xNb2O5-(14.7-x)Na2O--10ZnO--5K2O--10GeO2--
60TeO2--0.3Er2O3
(x=0, 3, 5, 7 and 9) have been investigated for developing 1.5~μm
fibre and planar amplifiers. The effects of Nb2O5 on the thermal stability
and optical properties of Er3+-doped tellurite glasses have been discussed.
It is noted that the incorporation of Nb2O5 (x=5) increases the thermal
stability of tellurite glasses significantly. Er3+-doped niobium tellurite
glasses exhibit a large stimulated emission cross-section (7.2\times 10-21-
10.7×10-21~cm2 and the gain bandwidth, FWHM×\sigmae^{\rm peak} (274\times 10-28 - 480×10-28~cm3), which are
significantly higher than that of silicate and phosphate glasses. In addition, the
intensity of upconversion luminescence of the Er3+-doped niobium tellurite
glasses decreases rapidly with increasing Nb2O5 content. As a result,
Er3+-doped niobium tellurite glasses might be a potential candidate for
developing laser or optical amplifier devices. 相似文献
89.
All-electron full-potential linearized augmented plane-wave calculations of the surface energy, work function, and interlayer spacings of close-packed metal surfaces are presented, in particular, for the free-electron-like metal surfaces, Mg(0 0 0 1) and Al(1 1 1), and for the transition metal surfaces, Ti(0 0 0 1), Cu(1 1 1), Pd(1 1 1), and Pt(1 1 1). We investigate the convergence of the surface energy as a function of the number of layers in the slab, using the Cu(1 1 1) surface as an example. The results show that the surface energy, as obtained using total energies of the slab and bulk from separate calculations, converges well with respect to the number of layers in the slab. Obviously, it is necessary that bulk and surface calculations are performed with the same high accuracy. Furthermore, we discuss the performance of the local-density and generalized gradient approximations for the exchange-correlation functional in describing the various surface properties. 相似文献
90.
用射频磁控溅射结合传统退火的方法制备LiCo0.8M0.2O2 (M=Ni,Zr)阴极薄膜.X射线衍射、拉曼光谱、扫描电子显微镜等手段表征了不同掺杂的LiCo0.8M0.2O2薄膜.结果显示,700℃退火的LiCo0.8M0.2O2薄膜具有类似α-NaFeO2的层状结构.通过对不同掺杂锂钴氧阴极的全固态薄膜锂电池Li/LiPON/LiCo0.8M0.2O2的电化学性能研究表明,电化学活性元素Ni的掺杂使全固态电池具有更大的放电容量(56μAh/cm2μm),而非电化学活性元素Zr的掺杂使全固态电池具有更好的循环稳定性. 相似文献