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101.
102.
Effects of Annealing on Schottky Characteristics in A1GaN/GaN HEMT with Transparent Gate Electrode 下载免费PDF全文
A1GaN/GaN heterostructure transistors are promising for power and switching applications. In addition, the transparent wide band-gap A1GaN/GaN heterostructure systems have received considerable attention to transparent electronics. Nowdays, Al-doped ZnO (AZO) thin film plays an increas- ingly important role in various fields of transparent electronics.The AZO-gated A1GaN/GaN HEMT with good dc characteristics and frequency character- istics has been reported. Annealing is widely used to improve the electri- cal characteristics of A1GaN/GaN HEMTs. It is re- ported that the Schottky leakage current can be re- duced by over four orders of magnitude by annealing in an A1GaN/GaN heterostructure with ITO/Ni/Au electrode. Pei et al. reported that the transparency of Ni/ITO gates of A1GaN/GaN HEMTs has been sig- nificantly improved after annealing. However, the evaluation of Schottky C V characteristics was ab- sent. Up to now, few results are reported on the Schot- tky annealing characteristics of AZO in A1GaN/GaN HEMT. Thus the effects of annealing on the leakage current, transparency and interface states character- istics need further study. 相似文献
103.
The nitrogen doping of ZnO film deposited by the magnetron sputtering method is subsequently realized by the hydrothermal synthesis method.The nitrogen-doped ZnO film is preferably(002) oriented.With the increase of hexamethylenetetramine(HMT) solution concentration,the average grain size of the film along the 002 direction almost immediately decreases and then monotonously increases,conversely,the lattice strain first increases and then decreases.The structural evolution of the film surface from compact and even to sparse and rough is attributed to the enhanced nitrogen doping content in the hydrothermal process.The transmission and photoluminescence properties of the film are closely related to grain size,lattice strain,and nitrogen-related defect arising from the enhanced nitrogen doping content with HMT concentration increasing. 相似文献
104.
为了降低光学表面的菲涅耳反射,提出了一种制备仿生减反结构的方法.利用银镜反应并结合退火处理在硬性材质基底表面制备银纳米粒子,经反应离子刻蚀工艺,在基底表面形成一层纳米蛾眼减反结构.分析了周期分布和随机分布纳米蛾眼的光学特性,实验研究了退火参量和刻蚀参量对银纳米颗粒直径、密度以及高度的影响,并在硅和石英基底上分别制备了随机减反结构.测试结果表明:硅基平均反射率小于4.5%,双面石英基透过率达98.1%.理论和实验均表明:随机分布的纳米仿生蛾眼结构具有宽光谱、广视角和高减反特性,所提出的制备方法具有简便易行、低成本、大幅面等优点,在光电器件中具有良好的潜在应用前景. 相似文献
105.
106.
Nanocrystalline Cu film with a mirror surface finishing is prepared by the electric brush-plating technique. The as- prepared Cu film exhibits a superhydrophilic behavior with an apparent water contact angle smaller than 10°. A subsequent increase in the water contact angle and a final wetting transition from inherent hydrophilicity with water contact angle smaller than 90° to apparent hydrophobicity with water contact angle larger than 90° are observed when the Cu film is subjected to natural aging. Analysis based on the measurement of hardness with nanoindentation and the theory of the bond-order-length-strength correlation reveals that this wetting variation on the Cu film is attributed to the relaxation of residual stress generated during brush-plating deposition and a surface hydrophobization role associated with the broken bond polarization induced by surface nanostructure. 相似文献
107.
Phase transition and thermal expansion property of Cr_(2-x)Zr_(0.5x)Mg_(0.5x)Mo_3O_(12) solid solution 下载免费PDF全文
Compounds with the formula Cr2-xZr0.5xMg0.5xMo3O12(x = 0.0, 0.3, 0.5, 0.9, 1.3, 1.5, 1.7, 1.9) are synthesized, and the effects of Zr4+ and Mg2+ co-incorporation on the phase transition, thermal expansion, and Raman mode are investigated. It is found that Cr2-xZr0.5xMg0.5xMo3O12 crystallize into monoclinic structures for x 〈 1.3 and orthorhombic structures for x _〉 1.5 at room temperature. The phase transition temperature from a monoclinic to an orthorhombic structure of Cr2Mo3O12 can be reduced by the partial substitution of (ZrMg)6+ for Cr3+. The overall linear thermal expansion coefficient decreases with the increase of the (ZrMg)6+ content in an orthorhombic structure sample. The co-incorporation of Zr4+ and Mg2+ in the lattice results in the occurrence of new Raman modes and the hardening of the symmetric vibrational modes, which are attributed to the MoO4 tetrahedra sharing comers with ZrO6/MgO6 octahedra and to the strengthening of Mo-O bonds due to less electronegativities of Zr4+ and Mg2+ than Cr3+, respectively. 相似文献
108.
正声学成像是一种用来检测物质结构和成分的重要方法,其分辨率受限于衍射极限(diffraction limit)。为了获取更高的分辨率,往往需要测量高空间频率的声倏逝波(acoustic evanescent wave)。倏逝波带有物体的细节特征信息,离开天然材料物体后的衰减特性满足指数关系。近年来,科学家利用结构声学超常材料(structured acoustic metamaterials,AMM)克服衍射极限,通过增强倏逝波 相似文献
109.
110.
Transport properties and anomalous fatigue effect of Ag/Bi0.9La0.lFeO3/La0.7Sr0.3MnO3 heterostructures 下载免费PDF全文
The transport properties and fatigue effect of Ag/Bi0.9La0.lFeO3/La0.7Sr0.3MnO3 heterostructures are described. By examining the I-V curves, an anomalous fatigue effect was found and its influences on resistive states were studied. I-V curves combined with C-f spectra were used to directly analyze the transport properties and fatigue effect. Compared to the first I-V cycle state, this structure shows more than one order increase of resistance after 100 cycles of "I-V curve training". The redistribution of oxygen vacancies in the depletion layer of Ag/Bi0.9La0.lFeO3 is believed to be responsible for the different resistance mechanisms and tenfold magnitude drop in resistance. The resistive switching is understood to be caused by electric field-induced carrier trapping and detrapping, which changes the depletion layer thickness at the Ag/Bi0.9La0.lFeO3 interface. 相似文献