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941.
Synthesis of {100} Facet Dominant Anatase TiO2 Nanobelts and the Origin of Facet‐Dependent Photoreactivity
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Dr. Feng Pan Prof. Kai Wu Prof. Hexing Li Prof. Guoqin Xu Prof. Wei Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(46):15095-15101
Sword‐like anatase TiO2 nanobelts exposed with 78 % clean {100} facets were synthesized and the facet‐dependent photoreactivity of anatase TiO2 was investigated. By quantitative comparison with the reference {001} facets, the {100} facets possessed about ten‐times higher active sites density than that on {001} facets, resulting in higher photoreaction efficiency. After the active sites density normalization, the {100} and {001} facets exhibited distinct wavelength‐dependent photocatalytic performance, attributed to the anisotropic electronic structures in TiO2 crystals. 相似文献
942.
943.
Structural and electrical properties of SrTiO3 thin films as insulator of metal-ferroelectric-insulator-semiconductor (MFIS) structures
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SrTiO3 (STO) thin films were deposited on p-Si(100) substrates at various substrate temperatures from 300℃ to 700℃ by radio frequency (RF) magnetron sputtering technique. Their structure and electrical properties were investigated. It was found that the transition from
amorphous phase to polycrystalline phase occurred at the substrate temperatures 300--400℃. Their crystallinity became better when the substrate temperatures further increased. The dielectric and leakage current measurements were carried out by using the Si/STO/Pt metal--insulator--semiconductor (MIS) structures at room temperature. It was found that the fixed charge density decreased and both the interface trap density and the dielectric constant increased when the substrate temperatures were increased. The leakage current mechanisms for STO MIS structures with STO films prepared at 700℃ followed the space charge limited current (SCLC) under the low applied electric field and the Poole--Frenkel emission under the high one. In addition, the resistivity for films prepared at 700℃ was higher than 1011\Omega \cdot cm under the voltage lower than 10V (corresponding to the electric field of 1.54\times 103kV\cdotcm-1). It suggested that the STO films prepared at 700℃ were suitable for acting as the insulator of metal--ferroelectric--insulator--semiconductor (MFIS) structures. 相似文献
944.
Y. H. Cheng H. Kupfer F. Richter Andreea Maria Paraian 《Applied Surface Science》2002,200(1-4):117-124
MgO films were deposited by pulsed mid-frequency magnetron sputtering from metallic targets in the mixture of Ar and O2 gas. The surface morphology, crystalline structure, and optical properties were characterized by using atomic force microscopy (AFM), X-ray diffraction (XRD), and spectroscopic ellipsometry, respectively. The secondary electron emission coefficients of MgO films were measured by using a self-made apparatus in He gas. A pronounced hysteresis phenomenon of target voltage, current, and deposition rate with increasing and decreasing O2 flow rate was observed. The structure of films deposited at a metallic mode changes from Mg phase to the mixed Mg and MgO phase, and the films have a very rough surface. All the films deposited at oxide mode have high transparency and smooth surface, and show (2 2 0) preferred orientation growth. The refractive index and extinction coefficient at a wavelength of 670 nm for MgO films deposited at oxide mode with a O2 flow rate of 3 sccm are 1.698 and 1.16×10−4, respectively. The secondary emission coefficient at a E/p of 57.8 V/(cm Torr) for MgO films deposited at a O2 flow rate of 3 sccm is 0.16, which is higher than that of MgO films deposited by e-beam evaporation. 相似文献
945.
由Bogoliubov-de Gennes方程得到铁磁超导共存态(FS)的自洽方程,利用推广的Furusaki-Tsukada的电流公式计算了铁磁超导态/绝缘层/自旋三重态p波超导体(FS/I/p)结的直流Josephson电流随结的温度、相位差以及FS中磁交换能、结界面的势垒散射强度的变化关系.研究表明:FS中磁交换能、结界面的势垒散射均抑制FS/I/p结的直流Josephson电流.当自旋三重态超导体具有px波配对势时,自旋三重态超导体结的直流Josephson电流随结两侧相位差的振荡周期是π.
关键词:
铁磁超导态
自旋三重态超导体
p波超导体
直流Josephson电流 相似文献
946.
An automated system for controlling oxygen flow in vacuum-plasma magnetron deposition of oxides with simultaneous monitoring
of gas impurities in a vacuum chamber is proposed. Features of using compact spectrometers in such a system are considered.
The precision of controlling the flow of metal and oxygen particles during deposition of Ti and Al oxides is determined. The
sensitivity to impurity content is estimated. The effect of sputtered metal and type of coating (metal or oxide) on the sensitivity
to impurities of air, water vapor, and oil in the vacuum chamber is found.
__________
Translated from Zhurnal Prikladnoi Spektroskopii Vol. 74, No. 3, pp. 412–416, May–June, 2007. 相似文献
947.
近年来,磁控溅射已成为重要的薄膜沉积技术之一。我国于1982年研制成功第一台磁控溅射镀膜机,比国外只晚几年。随后生产出各种中、小型磁控溅射镀膜机,主要用于制镜和美术陶瓷工艺品装饰性镀膜。 目前,国外发达国家已由装饰性镀膜过渡到功能膜,诸如电磁、光学、机械、防潮和 相似文献
948.
949.
E. T. W. M. Schipper O. Sindt T. Hamaide P. Lacroix-Desmazes B. Müller A. Guyot M. J. W. A. van den Enden F. Vidal J. J. G. S. van Es A. L. German A. Montaya Goñi D. C. Sherrington H. A. S. Schoonbrood J. M. Asua M. Sjöberg 《Colloid and polymer science》1998,276(5):402-411
A variety of nonionic reactive surfactants have been prepared from block copolymer precursors. These precursors are formed
from a commercially available polyoxyethylene glycol monomethylether as the hydrophilic sequence of the surfactant; this product
is used as initiator of ring opening anionic polymerization of butylene oxide. Finally the reactive surfactants are obtained
after proper functionalization of the precursor. The reactive surfactants are an inisurf with an asymmetric azo compound,
a transurf with a thiol group, and a few surfmers with acrylic, methacrylic, styrenic and α-methyl styrenic reactive groups.
These compounds have been engaged in styrene emulsion or dispersion polymerization. Several of them have been found to be
useful for preparing stable latices.
Received: 22 July 1997 Accepted: 11 December 1997 相似文献
950.
Simone Knaus Alexander Liska Peter Sulek 《Journal of polymer science. Part A, Polymer chemistry》2003,41(21):3400-3413
Several chelating monomers with methacrylate and maleimide residues as polymerizable groups and diketone and aspartic acid residues as metal‐bonding groups were synthesized. A long‐chain aliphatic spacer was introduced to increase the solubility of the monomers in the polymer melt and to enhance the compatibility of grafted side chains and homopolymers with polypropylene (PP). PP was functionalized by melt free‐radical grafting, and some properties of the modified polymer were investigated. The grafting of a chelating methacrylic ester by injection molding afforded grafting yields of 30–50%. A comparison with products obtained by the grafting of commercially available acetoacetoxy methyl methacrylate showed the beneficial effect of the aliphatic spacer with respect to the grafting yield as well as the tensile strength and flexural modulus. The grafting of an aspartic acid based maleimide in an extruder afforded grafting yields of 80–95% and a significant increase in the surface wettability, as shown by contact‐angle measurements. A comparative study using samples obtained by the grafting of maleimidobenzoic acid indicated that the homogeneity‐increasing effect of the spacer was neutralized by the detrimental effect of the dicarboxylic chelating group. Nevertheless, the results showed that the maleimides were well suited for grafting by reactive extrusion because of their low susceptibility to homopolymerization under melt‐processing conditions. Preliminary metalization experiments showed the feasibility of plating without the use of corrosive etchants. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3400–3413, 2003 相似文献