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11.
Ir.H.E.M. Stassen 《Renewable Energy》1994,5(5-8)
Within the European Community, the interest in energy generation from biomass and waste is increasing. A brief overview is given of several thermal conversion technologies, of biomass production and waste availability in the Netherlands. Based on this, the possibilities for energy generation from biomass and waste in the Netherlands are evaluated. 相似文献
12.
The influence of irreversibility of finite-rate heat transfer on the performance of an absorption refrigerator is investigated using an endoreversible cycle model with continuous flow. The cooling rate is adopted as an objective function for refrigerator optimization. The maximum cooling rate and the corresponding coefficient of performance are derived. The optimal performance with respect to heat transfer areas of the refrigerator is analysed. In addition, certain significant conclusions are reached. 相似文献
13.
A framework is presented for examining the effectiveness of limiting and modelling arguments used in the analysis of fluid
flows. It consists of examining the consequences of the arguments on the flow problem as a whole and breaking down the limiting/modelling
process into a sequence of steps and associated sequence of flow problems, termed here as ‘lidels’. The notion of validity
of lidels is given. Several examples are given to explain the present approach.
Invited general lecture at 3rd ACFM, Tokyo, September 1986 相似文献
14.
J G De Nobel F M Klis A Ram H Van Unen J Priem T Munnik H Van Den Ende 《Yeast (Chichester, England)》1991,7(6):589-598
To study cell-cycle-related variations in wall permeability of Saccharomyces cerevisiae, two approaches were used. First, an asynchronous culture was fractionated by centrifugal elutriation into subpopulations containing cells of increasing size. The subpopulations represented different stages of the cell cycle as judged by light microscopy. Cell wall porosity increased when these subpopulations became enriched with budded cells. Secondly, synchronous cultures were obtained by releasing MATa cells from alpha-factor induced G1-arrest. These cultures grew synchronously for at least two generations. The cell wall porosity increased sharply in these cultures, shortly before buds became visible and was maximal during the initial stages of bud growth. It decreased in cells which had completed nuclear migration and before abscission of the bud had occurred. The porosity reached its lowest value during abscission and in unbudded cells. We examined the incorporation of mannoproteins into the wall during the cell cycle. SDS-extractable mannoproteins were incorporated continuously. However, the incorporation of glucanase-extractable mannoproteins, which are known to affect cell wall porosity, showed cyclic oscillations and reached its maximum after nuclear migration. This coincided with a rapid decrease in cell wall porosity, indicating that glucanase-extractable mannoproteins might contribute to this decrease. 相似文献
15.
Stefan Kasapis 《International Journal of Food Science & Technology》2002,37(4):403-413
The structural properties of mixtures of pectin, oxidized starch and glucose syrup were investigated using small deformation dynamic oscillation. In the absence of added calcium, preparations of low methoxy pectin with glucose syrup formed viscous solutions, which remained crystal-free at subzero temperatures. Samples of oxidized starch and glucose syrup, on the other hand, exhibited solid-like behaviour because of the crystalline nature of the amylose-like helices. Mixtures of the two polysaccharides with the co-solute clearly showed phase inversion from liquid to solid-like behaviour with increasing amounts of starch in the formulation. The transformation was reflected in the textural properties of samples, which varied from thick solutions to firm gels. The viscoelasticity of the system was modified further by the introduction of high methoxy pectin. Preparations of high methoxy pectin and glucose syrup formed rubbery gels whose amorphous nature underwent a glass transition during cooling. 相似文献
16.
17.
陈海 《中国海上油气(工程)》2002,(4)
海上无人驻守简易平台设计是降低原油成本的重要手段之一,密闭循环涡轮发电机组(Closed Cycle Vapor Turbogenerator)是海上无人驻守平台上应用最可靠且低维护的远程发电系统。介绍CCVT这种发电机组,并讨论了在海上工程设计中需要考虑的问题,为今后简易平台上电站的选择设计提供参考。 相似文献
18.
通过改变激光器的相对激发,观察到了氩离子激光器振荡频率的演变特性。用模竞争效应对实验现象进行了理论解释。 相似文献
19.
An open‐cycle ocean thermal energy conversion (OC‐OTEC) system is one of the energy conversion methods used to generate electricity from ocean thermal energy. For the OC‐OTEC system, steam evaporated from the surface seawater due to flash evaporation drives the turbine. At that time, dissolved gas such as air is introduced into the low‐pressure system (OC‐OTEC system) as the noncondensable gas, which degrades the performance of condensation heat transfer. In this paper, a small‐scale OC‐OTEC experimental unit experimentally investigates the effect of noncondensable gas on the heat transfer performance in a condenser. The experimental results are discussed in comparison with theoretical estimation by the Sparrow–in method. It is shown that the condensation is occupied by heat and mass transfer near a condensation surface and that the condensation efficiency is affected by exhaust quantity of noncondensable gas at a relatively high concentration ratio of condensable gas. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(1): 29–35, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20179 相似文献
20.
高分辨率层序地层学克服了岩性地层对比穿时的缺点.高分辨率层序地层对比是等时的高精度的地层对比,它满足了勘探开发中地层对比等时性和高分辨率的要求.测井资料的纵向分辨率较高,是高分辨率层序地层研究的重要资料.提出了利用测井相分析技术,从测井资料上识别出单井岩性和沉积微相剖面,结合测井曲线特征,划分单井基准面旋回,并进行连井地层等时对比,这为定量地进行高分辨率层序地层分析提供了一种方法.通过研究区实际资料的处理,验证了该方法的有效性. 相似文献