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71.
研究了激光二极管(LD)抽运的自拉曼Nd∶YVO4调Q激光器的特性。Nd∶YVO4晶体同时作为激光介质和拉曼晶体,通过声光调Q技术,产生了1176 nm的拉曼激光。测量了平均输出功率、脉冲宽度和单脉冲能量随抽运功率和脉冲重复率的变化。典型的1064 nm基频光和1176 nm拉曼光脉冲的脉冲宽度分别为26.3 ns和9.0 ns。在脉冲重复率为20 kHz,抽运功率为8.46 W时,产生了平均功率为0.384 W的1176 nm光的输出,光-光转换效率为4.54%。使用速率方程对自拉曼Nd∶YVO4调Q激光器特性进行了理论研究,把脉冲重复率为10 kHz,20 kHz,30 kHz时拉曼光单脉冲能量和脉冲宽度的实验值与理论值进行了比较,结果基本相符。 相似文献
72.
73.
对采用SBS调Q产生喇曼频移输出的激光器进行了理论分析,并对实验结果与染料调Q时的输出进行了对比,提出了改进该种激光器性能的方法。 相似文献
74.
The objective of this work is to develop and validate the basis of a novel laser modeling and design methodology that incorporates a global optimization approach. Classical modeling techniques typically involve design evaluations that are conducted at the laser's threshold injection current. This is the point where the laser is just turning on, and the (standard practice) numerical challenge is minimal. The fundamental difference offered by the proposed new methodology is the possibility of developing laser designs directly at the injection current (power level) of interest.The effectiveness of the new methodology is verified by considering the computationally difficult problem of maximizing a laser's internal (cavity) field flatness over a range of above-threshold injection currents, while also considering the boundary condition error of the laser's internal field solution. Global optimization is then used to find an optimally flat field solution in terms of the laser's structural design parameters. The favorable comparison between our results and the results obtained by the extrapolation of threshold designs to the same injection current indicate the self-consistency and fundamental capabilities of the new methodology. 相似文献
75.
Analysis of Thermal Effects in Laser Rod Pumped by Repetitively Pulsed Laser Diode Array 总被引:1,自引:0,他引:1
DAI Qin LI Xin-zhong WU Ri-na WANG Xi-jun 《半导体光子学与技术》2007,13(4):283-288
Based on some assumptions, the numerical model of thermal distribution in solid state laser crystal pumped by pulsed laser diode is set up due to the pumped intensity distribution. Taking into account the property of YAG materials that varies with temperature, the transient temperature distribution of the laser crystal is calculated using finite element method on condition that K is a constant and a function of temperature. Then, the influence of the pumping parameters on the thermal effect in laser crystal is also discussed. This study is helpful to optimize the design of the diode side pumped solid state lasers. 相似文献
76.
77.
Ryan P. Smith Peter A. Roos Jared K. Wahlstrand Jessica A. Pipis Maria Belmonte Rivas Steven T. Cundiff 《Journal of research of the National Institute of Standards and Technology》2007,112(6):289-296
We perform optical frequency metrology of an iodine-stabilized He-Ne laser using a mode-locked Ti:sapphire laser frequency comb that is stabilized using quantum interference of photocurrents in a semiconductor. Using this technique, we demonstrate carrier-envelope offset frequency fluctuations of less than 5 mHz using a 1 s gate time. With the resulting stable frequency comb, we measure the optical frequency of the iodine transition [127I2 R(127) 11-5 i component] to be 473 612 214 712.96 ± 0.66 kHz, well within the uncertainty of the CIPM recommended value. The stability of the quantum interference technique is high enough such that it does not limit the measurements. 相似文献
78.
Hirotaka SoHirofumi Watanabe Masayuki YahiroYu Yang Yuji OkiChihaya Adachi 《Optical Materials》2011,33(6):755-758
In this study, we synthesized the new spirobifluorene derivatives; hexylbiphenyl-spirobifluorene (HBP-Spiro) and triphenylamine-spirobifluorene (TPA-Spiro) and demonstrated the operation of a distributed-feedback polymer waveguide blue laser. In addition, we investigated the optical and lasing properties of spirobifluorene derivatives including photostability. The experimental slope efficiency and the energy threshold of a HBP-Spiro-doped waveguide laser were 3.6% and 1.9 μJ, respectively. An operation lifetime of 27,000 shots was obtained for a pump-pulse duration of 1.2 ns and energy of 3.0 μJ at a wavelength of 355 nm. 相似文献
79.
《Journal of Nuclear Science and Technology》2013,50(12):956-963
Optical trappings of ThO2 and UO2 particles have been first demonstrated in water using the radiation pressure of a TEM00-mode He-Ne laser beam of λ=633 nm. It was observed that a ThO2 particle was successfully trapped three-dimensionally in the focus region and transferred by moving the focus. On the other hand, for a UO2 particle of which a refractive index and an extinction coefficient are relatively large in the visible region, only two-dimensional trapping was observed when the beam focus was located near the bottom of the particle. One of the main difficulties in the optical trapping of nuclear fuel particles is attributed to their relatively large absorption coefficients in the visible region. Computational studies on three-dimensional optical trapping performances of absorbing particles were, therefore, perfomed with a simulation code based on geometrical optics. The present calculation can well predict the experimental results on the optical trapping characteristics for ThO2 and UO2 particles. 相似文献
80.
K. A. Soubbotin V. A. Smirnov S. V. Kovaliov H. J. Scheel E. V. Zharikov 《Optical Materials》2000,13(4):405-410
Single crystals of germanoeucryptite doped by chromium (IV) have been grown for the first time. Spectroscopic properties of grown crystals have been investigated. The intensive broadband fluorescence of Cr4+-ions in the range between 1070 and 1600 nm was observed with lifetime 10 μs. Preliminary investigations show that this material is promising for use as an active medium for new tunable solid-state laser of near IR-region. 相似文献