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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
作为智能交通系统中的重要组成部分,最优路径选择直接决定着智能交通系统的用户体验。该文使用GIS数据模型,将道路抽象为由点和线组成的图,并根据图论理论构建出交通网络模型。在此基础上研究智能交通系统的最优路径选择的问题,同时考虑到交通系统中的实际问题,改进了Dijkstra算法,从而缩短最优路径搜索时间,提高系统效率。 相似文献
992.
993.
GENG Jun-bao JIN Jia-shan ZHANG Jun College of Naval Architecture Power Naval University of Engineering Wuhan P.R. China 《国际设备工程与管理》2010,(1)
Reliability, maintainability, supportability (RMS) are the important performance indexes of equipment, which affect not only the availability, but also the life cycle cost (LCC) of the equipment. First discussed is the qualitative relation between reliability and LCC and the costs which may be used to enhance the reliability. Secondly, the factors that affect the maintainability are summarized, and if maintainability is advanced, the trend of the LCC is depicted. Thirdly, the qualitative relation between th... 相似文献
994.
995.
芦长椿 《高科技纤维与应用》2013,38(4):46-51
综述了已投入商业化运营的纳米碳纤维(CNF)生产工艺,诸如化学汽相沉积法(CVD)、静电纺丝法技术状况以及相关的生命周期分析数据。表明纳米尺度的碳纤维及其复合材料是一种多功能材料,具有优良的导电性、力学增强性和热性能。在纳米复合材料、贮氢和催化载体领域显示出了市场潜力。 相似文献
996.
Paul Centore 《Color research and application》2013,38(2):110-119
This article demonstrates that the CIE XYZ colour solid is a zonoid. An approximating zonohedral colour solid is constructed explicitly from a set of generating vectors, which are integrals of colour‐matching functions over narrow intervals of the visible spectrum. The zonohedral approach yields an intuitive, constructive proof of the Optimal Colour Theorem: the reflectance function of an optimal colour takes on only the values 0 or 1, with at most two transition wavelengths. In addition, zonohedral techniques can simplify computations: for example, optimal colours can be found without calculating transition wavelengths. Finally, zonohedra provide a simple, unified approach to colour space and eliminate much of the confusion arising from chromaticity diagrams. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2013 相似文献
997.
The environmental performance of hydrogen production via indirect gasification of poplar biomass was evaluated following a Life Cycle Assessment approach. Foreground data for the study were provided mainly from process simulation. The main subsystems and processes that contribute to the environmental impacts were identified. Thus, poplar production and direct emissions to air from the processing plant were found to be the main sources of environmental impact. Furthermore, a favourable (positive) life-cycle energy balance was estimated for the gasification-based system. 相似文献
998.
F. Haglind 《Energy》2010
The part-load performance of gas and steam turbine combined cycles intended for naval use is of great importance, and it is influenced by the gas turbine configuration and load control strategy. This paper is aimed at quantifying the effects of variable geometry on the gas turbine part-load performance. Subsequently, in another paper, the effects of variable geometry on the part-load performance for combined cycles used for ship propulsion will be presented. Moreover, this paper is aimed at developing methodologies and deriving models for part-load simulations suitable for energy system analysis of various components within gas turbines. Two different gas turbine configurations are studied, a two-shaft aero-derivative configuration and a single-shaft industrial configuration. When both gas turbine configurations are running in part-load using fuel flow control, the results indicate better part-load performance for the two-shaft gas turbine. Reducing the load this way is accompanied by a much larger decrease in exhaust gas temperature for the single-shaft gas turbine than for the two-shaft configuration. As used here, the results suggest that variable geometry generally deteriorates the gas turbine part-load performance. 相似文献
999.
Arne Sloth Jensen 《Drying Technology》2013,31(5-7):1377-1393
ABSTRACT Drying in superheated steam under pressure gives possibilities for pollution free drying, energy recovery. reduced drying time and a very compact drying equipment. Products are dried i n a pressurized cellular fluid bed by super heated steam blown through the cells. Above the fluid bed dust is separated before the steam is reheated and recirculated to the cells by a fan. The evaporated water leaves the dryer as usable steam at e.g. 3 bar g, and full energy recovery is obtained. Today 14 plants have been builtor are under construction, with capacities from 2 to 40t / h water evaporation. This technology is suited for drying of beet pulp, residues from starch production of corn or wheat. sludge. spent grain. brown coal. wood chips and bark. The technology shows great options for integration in steam systems in various industries, whereby drying is possible without using primary energy and pollution is avoided. 相似文献
1000.
The simulation model of a transcritical CO2 heat pump dryer presented in Part 1 has been first validated with available experimental data in this part and then used to simulate the heat pump dryer to study the variation of performance parameters such as heating COP, moisture extraction rate, and specific moisture extraction rate. The validation with experimental data shows that the model slightly over predicts the system performance. The possible reasons for the difference between experimental and numerical results are explained. Simulation results show the effect of key operating parameters such as bypass air ratio, re-circulation air ratio, dryer efficiency, ambient condition (temperature and relative humidity), and air mass flow rate. Results show that unlike bypass air ratio and ambient relative humidity, the effect of dryer efficiency, recirculation air ratio, ambient temperature, and air mass flow rate are very significant as far as the system performance is concerned. 相似文献