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排序方式: 共有2180条查询结果,搜索用时 11 毫秒
71.
介绍了太赫兹波的发展现状及主要特性。重点介绍太赫兹波在军事、航天领域里的应用。尤其是在卫星通信、卫星成像与探测、空间态势感知和导弹防御等方面,太赫兹波有着很好的发展前景。本文给出太赫兹技术在军事和航天领域的最新进展,特别是在武器装备测试方面,太赫兹技术有着广泛的应用前景。文章可为太赫兹技术在军事领域的进一步应用提供技术参考。 相似文献
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73.
A new lunar highland soil simulant, NAO-1, has been created in National Astronomical Observatories (NAO), Chinese Academy of Sciences. This simulant was produced by gabbro, which includes large quantity of feldspar (An>90). The simulant’s chemical composition, mineralogy, particle-size distribution, density, angle of internal friction, and cohesion have been analyzed and results demonstrated that most characteristics of NAO-1 are similar with lunar highland soil samples. NAO-1 will benefit the scientific and engineering research of lunar soil. 相似文献
74.
Bo Lai Qingqing Ji Yue Yuan Donghai Yuan Yuexi Zhou Juling Wang 《Korean Journal of Chemical Engineering》2016,33(1):207-215
To investigate the degradation of high concentration pollutant by Fe/Cu bimetallic system at a high operating temperature, 10,000mg/L acid orange 7 (AO7) aqueous solution was treated by Fe/Cu bimetallic system at 80 oC. First, the effect of the operating temperature (30-80 °C) on the reactivity of Fe/Cu bimetallic particles was investigated thoroughly. Then, the studies on the effect of theoretical Cu mass loading, Fe/Cu dosage, stirring speed and initial pH on the reactivity of Fe/Cu bimetallic particles at a high temperature (i.e., 80 °C) were carried out, respectively. The degradation and transformation process of AO7 was studied by using COD, TOC and UV-Vis spectra. The results indicate that high concentration pollutant could be removed effectively by Fe/Cu bimetallic system at a high operating temperature. And the removal efficiencies of AO7 by Fe/Cu bimetallic system were in accordance with the pseudofirst- order model. Finally, it was observed that the high temperature could accelerate mass transport rate and overcome the high activation energy barrier to significantly improve the reactivity of Fe/Cu bimetallic particles. Therefore, the higher removal efficiency could be obtained by Fe/Cu system at a high operating temperature. Thus, the high operating temperature played a leading role in the degradation of high concentration pollutant. 相似文献
75.
76.
《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1988,30(1):105-109
We analyze the proposed Karlsruhe electron storage ring for X-ray in-depth lithography using the 3rd order charged particle beam transport code MARYLIE 3.0. The ring features four 90° superconducting bending magnets. A numerical calculation of their field provides the longitudinal dependence of the multipole expansion coefficients. These are used by the code SCB to compute the Lie algebraic transfer map. Subsequent particle tracking with MARYLIE is employed to find dynamic apertures. Two different magnet designs which both lead to satisfactory dynamic apertures are presented. 相似文献
77.
78.
LI Tianshu YANG Yanhua LI Xiaoyan HU Zhihua 《核技术(英文版)》2007,18(4):252-256
A series of experiments of the premixing stage of fuel-coolant interactions (FCI), namely the particles falling into water, were carried out. The force on the particles during the course of falling has been studied. The dropping character of hot particle was influenced by three main parameters, i.e., particle temperature, particle diameter and coolant subcooling that varied over a wide range. A high-speed camera recorded the falling speed of the particle and the moving curves were obtained. The experimental results showed that for the film boiling on the surface of particle and water, the temperature increase of either particle or coolant would slow down the particle falling velocity. The falling velocity of particle in small diameter is lower than that of the bigger particle. The present work can provide an experimental foundation for further investigation of high-speed transient evaporation heat transfer. 相似文献
79.
《Materials Chemistry and Physics》1987,17(3):293-300
An attempt to evaluate the surface area of hematite and rutile occupied by an adsorbed molecule of polyvinyl alcohol(PVA) was made. The surface area occupied by a PVA molecule was evaluated from the changes of surface charge density of the oxides before and after PVA addition in the presence of Cs+, Mg2+, and Ca2+ ions. The desorption of an inorganic ion caused by PVA adsorption was taken into account. The configuration of the PVA chain at the solid — liquid interface is also discussed in the light of the results obtained. 相似文献
80.
超高速FFT处理器的设计与实现 总被引:2,自引:1,他引:2
为了满足精密检测系统的需要,设计高速FFT是系统的核心问题,而并行流水线技术是实现大规模高速FFT运算的基本技术。该FFT处理器主要基于现场可编程门阵列芯片(FPGA), 采用并行处理和SDF(Single—path Delay Feedback)流水线技术,内存资源较并行结构有所减少,运算速度较单独的SDF流水线结构有所提高。建立了处理器的算法和设计模型,并根据模型对处理器组成模块进行了优化设计,在保证处理器速度的同时,大大减小了资源消耗,其工作频率可以达到150MHz,数据率超过600Msps,其FPGA仿真结果和实验室平台测试验证了设计的可行性。 相似文献