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261.
Ch. Muller D. Deleruyelle R. Müller M. Thomas A. Demolliens Ch. Turquat S. Spiga 《Solid-state electronics》2011,56(1):168-174
The present paper deals with the bipolar resistive switching of memory elements based on metal-organic complex CuTCNQ (copper-7,7’,8,8’-tetracyanoquinodimethane) nanowires grown on a dedicated HfO2 oxide switching layer. Switching characteristics are explored either at millimeter scale on pad-size devices or at nanoscale by using conductive atomic force microscopy. Whatever the investigation scales, the basic memory characteristics appear to be controlled by copper ionic transport within a switching layer. This latter corresponds to either HfO2 layer in pad-size devices or nanogap formed at nanoscale between the atomic force microscopy conductive tip and CuTCNQ surface. Depending upon the observation scale, the switching layer (either HfO2 oxide or nanogap) acts as a matrix in which copper conductive bridges are formed and dissolved thanks to redox processes controlled in alternating applied bias voltages. 相似文献
262.
263.
详细介绍了基于不同种类微纳光纤的光源、光耦合器、光开关和滤波器的结构、工作过程及性能参数,总结了基于微纳光纤的光纤通信器件的研究进展情况。指出微纳光纤器件的实用化是光纤通信器件的发展方向。 相似文献
264.
V. S. Pershenkov V. V. Belyakov S. V. Cherepko I. N. Shvetzov-Shilovsky V. V. Abramov 《Microelectronics Reliability》1999,39(1):133
The work is concerned with the properties of conventional MOSFET in bipolar mode of operation. It is shown that the base current can provide useful information about interface trap density at the Si–SiO2 interface. The new device characteristics are found promising for use in low-voltage low-power logic circuits. 相似文献
265.
G. MurugananthamK. Ravichandran K. SaravanakumarA.T. Ravichandran B. Sakthivel 《Superlattices and Microstructures》2011,50(6):722-733
Undoped and fluorine doped tin oxide films were deposited from starting solutions having different values of solvent volume (10-50 ml) by employing a low cost and simplified spray technique using perfume atomizer. X-ray diffraction studies showed that there was a change in the preferential orientation from (2 1 1) plane to (1 1 0) plane as the volume of the solvent was increased. The sheet resistance (Rsh) of undoped SnO2 film was found to be minimum (13.58 KΩ/□) when the solvent volume was lesser (10 ml) and there was a sharp increase in Rsh for higher values of solvent volume. Interestingly, it was observed that while the Rsh increases sharply with the increase in solvent volume for undoped SnO2 films, it decreases gradually in the case of fluorine doped SnO2 films. The quantitative analysis of EDAX confirmed that the electrical resistivity of the sprayed tin oxide film was mainly governed by the number of oxygen vacancies and the interstitial incorporation of Sn atoms which in turn was governed by the impinging flux on the hot substrate. The films were found to have good optical characteristics suitable for opto-electronic devices. 相似文献
266.
计量窃电智能化遥距侦测和取证的应用研究综合应用现行营销在线监控的各系统对用户,采用计量自动化遥距侦测并分析窃电行为,同时启动现场摄像机取证。降低了供电企业管理成本,并确保了整个社会和谐发展及电力安全和稳定供应。 相似文献
267.
Paula C. Barbosa Luísa C. Rodrigues Maria Manuela Silva Michael J. Smith Prudência B. Valente Alexandra Gonçalves Elvira Fortunato 《先进技术聚合物》2011,22(12):1753-1759
Solid polymer electrolyte (SPE) systems based on interpenetrating blends of poly(ethylene oxide‐co‐propylene oxide) and poly(methyl methacrylate) host matrices, with lithium perchlorate as guest salt, were prepared. These electrolytes were presented as free‐standing films, and their thermal and electrochemical properties were characterized by conductivity and electrochemical stability measurements. The properties of the interpenetrating blends of poly(ethylene oxide‐co‐propylene oxide) and poly(methyl methacrylate) host matrices as the electrolyte component of a solid‐state electrochromic device are reported and the results obtained suggest that this electrolyte provides an encouraging performance in this application. The most conducting electrolyte composition of this SPE system is the formulation designated as SPE2‐0PC (5.01 × 10?4 S cm?1 at about 57°C). The lowest decomposition temperature was registered with the SPE6‐15PC composition (233°C). The average transmittance in the visible region of the spectrum was above 41% for all the samples analyzed. After coloration the device assembled with 71 wt% PC presented an average transmittance of 15.71% and an optical density at 550 nm of 0.61. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
268.
Chirped fibre Bragg grating based multiplexer and demultiplexer for DWDM applications 总被引:1,自引:0,他引:1
R. Romero O. Frazo F. Floreani L. Zhang P.V.S. Marques H.M. Salgado 《Optics and Lasers in Engineering》2005,43(9):987-994
A multiplexer/demultiplexer for 100 GHz channel spacing based on chirped fibre Bragg gratings with different bandwidths and optical circulators is presented. The spectral characteristics, specifications and operation of these passive devices are described, showing its potential use in dense wavelength division multiplexing (DWDM) applications. 相似文献
269.
本文结合笔者的科研,论述了离子注入在Power MOS FET制作中的应用,并指出:由于离子注入较之扩散具有一系列优点,因此,离子注入不仅在制作Power MOS FET中作用巨大,而且在其他功率器件中的应用也将越来越广泛。 相似文献
270.
k 《Physica E: Low-dimensional Systems and Nanostructures》2005,25(4):238
The modified k·p method (which includes both stress and polarization effects) has been used to investigate recombination phenomena in nitride quantum-well (QW) devices. Within their volumes, both spontaneous and piezoelectric polarization have been found to have an essential influence on carriers behaviour. In particular, as a result of the quantum-confined Stark effect, energy of radiation emitted within the AlGaN/GaN/AlGaN QW has been found to decrease rapidly with an increase in the AlN mole fraction of the barrier material, which means—with an increase in mechanical stresses at the GaN/AlGaN heterojunctions. It should also be stressed that screening of polarization effects induced by free carriers at least partly reduced the above stress influence. So both effects, polarization and its screening, are equally important in exact modelling of an operation of nitride QW devices. 相似文献