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991.
X. Portier C. Ternon F. Gourbilleau C. Dufour R. Rizk 《Physica E: Low-dimensional Systems and Nanostructures》2003,16(3-4):439
Photoluminescence spectroscopy, Fourier transform infrared spectroscopy, X-ray reflectometry and high resolution electron microscopy have been used to interpret the photoluminescence properties of annealed (3/19 nm) Si/SiO2 multilayers grown by reactive magnetron sputtering. The multilayers show an emission in the visible and near-infrared range after heat treatment from 900°C which tends to decrease from 1200°C. Three different origins for the photoluminescence activity have been found. An anneal temperature of 1200°C is necessary to optimise the silicon crystallisation within the silicon sublayers. 相似文献
992.
Synthesis and Molecular Structure of Two 1-Sila-3-alanata-cyclobutane Derivatives with Four-membered AlC2Si-Heterocycles The C? H acidic bis(trimethylsilyl)methyl compounds Me3C? AlR2 und Me3C? CH2? AlR2 (R ? CH(SiMe3)2) are deprotonated by treatment with the sterically high shielded base LiCH(SiMe3)2 in the presence of 1,3,5-trimethylhexahydrotriazinane. The deprotonation occurs at a methyl group of one of the element-organic substituents, and the formed carbanions are stabilized by coordination to the unsaturated Al atoms yielding four-membered heterocycles. Both products were characterized by a crystal structure determination each showing bent ring systems. 相似文献
993.
Using coaxial impact collision ion scattering spectroscopy, we have investigated Sn thin film growth on Si(1 1 1)√3×√3-Sn and hydrogen-terminated Si(1 1 1) surfaces at room temperature. Sn formed crystalline film with β-Sn structure on Si(1 1 1)√3×√3-Sn surface, but on the hydrogen-terminated Si(1 1 1) surface, the epitaxial growth of Sn thin film was disrupted, and Sn grew as a polycrystalline film. The growth orientational relationship of the Sn film grown on Si(1 1 1)√3×√3-Sn surface was found to be . In the works, we found that interface structure plays a decisive role for the growth mode, crystallinity, and growth orientation of the growth of thin film. 相似文献
994.
Electrical conductivities, Seebeck coefficients and thermal diffusivities were measured for Ru2Si3 samples with different densities prepared by spark plasma sintering method and an Rh-doped sample prepared by the floating
zone melting and spark plasma sintering methods. Electrical conductivities, Seebeck coefficients and thermal diffusivities
increased with sample density for undoped Ru2Si3. The thermoelectrical figure of merit also increased with sample density. Electrical conductivity of the 4% Rh-doped sample
was larger than that of our previous samples prepared by floating zone melting method. Values of Seebeck coefficients were
similar for samples prepared by either method.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
995.
We have investigated the growth mode and surface morphology of CaF2 film on Si(1 1 1)7×7 substrate by reflection high-energy electron diffraction (RHEED) using very weak electron beam and atomic force microscopy (AFM). It was found by RHEED intensity oscillation measurements and AFM observations that three-dimensional (3D) islands grow at RT; however, rather flat surface appears with two-dimensional (2D) islands around 300 °C. Especially, at high temperature of 700 °C, characteristic equilateral triangular terraces (or islands) with flat and wide shape grow with the tops directed toward [1 1 −2] of substrate Si(1 1 1). On the other hand, the desorption process of the CaF2 film due to electron stimulated desorption (ESD) was also examined. It was found that the ESD process at 300 °C forms characteristic equilateral triangular craters on the film surface with the tops (or corners) directed toward [−1 −1 2] of substrate Si(1 1 1), provided that the film was grown at 700 °C. 相似文献
996.
本文利用Auger分析技术和C-V测量方法,详细地研究了PECVDSi3N4/InP界面特性,Auger能谱分析表明热处理使界面面发生互扩散,同时InP的热分解导致P元素穿过Si3N4薄膜到达表面。C-V测量表明Ag/Si3N4/InPMIS结构可以实现载流子的堆积、耗尽和反型。 相似文献
997.
采用Nakatsuji提出的对称匹配耦合簇相互作用(SAC-CI)方法,计算了Si(CH3)2O双自由基分子的基态,单重三重激发态,阳离子二重态和阴离子二重态的激发能,光电子谱,电离能等.结果表明,SAC-CI方法比TDDFT有明显优势. 相似文献
998.
对nc-Si/SiO2薄膜中纳米硅(nc-Si)、Er3+和非辐射复合缺陷三者间的关系作了研究.在514.5 nm光激发下,nc-Si/SiO2薄膜在750nm和1.54μm处存在较强的发光,前者与薄膜中的nc-Si有关,后者对应于Er3+从第一激发态4I13/2到基态4I15/2的辐射跃迁.随薄膜中Er3+含量的提高,1.54μm处的发光强度明显增强,750 nm处的发光强度却降低.H处理可以明显增强薄膜的发光强度,但是对不同退火温度样品,处理效果却有所不同.根据以上实验结果,可得如下结
关键词:
Er3+
nc-Si
H处理 相似文献
999.
1 IntroductionWiththeonlyexceptionthatthesmallimpurityorminorityatomscanmovebytheinterstitialmechanism ,itismostlythevacancythatisheldresponsibleforthediffusionofatomsintheorderedalloys[1 ] .Itwasgenerallyconsideredthattheminorityatomsintheorderedalloys,s… 相似文献
1000.
利用x射线衍射和磁测量研究了不同稳定元素Co以及Ti,V和Cr替代对Nd3Fe29-x-yCoxMy(M=Ti,V,Cr)化合物结构和磁性的影响.研究发现:每一个稳定元素都有一替代量极限,在此极限以内所有化合物均为Nd3(Fe,Ti)29型结构,A2/m空间群.不同稳定元素的溶解极限不同.Co的替代量与稳定元素有关,当以Cr作为稳定元素时,Cr的替代量随着Co含量的提高而提高
关键词:
3(Fe')" href="#">Nd3(Fe
Co
29')" href="#">M)29
结构
磁性 相似文献