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991.
992.
An experimental study of two-phase flow in a 180° pipe bends with 0.016, 0.022 and 0.03 m and the curvature radii of 0.11, 0.154, 0.21 m, respectively have been carried out. The experiments were conducted under the input superficial phase velocity: air from 0.038 to 5.4 m s−1, water from 0.018 to 0.92 m s−1 and oil from 0.014 to 0.92 m s−1. The conducted research involved the observation of the forming flow patterns and determination of average volumetric in situ gas fraction. On the basis of the results of experimental flow map was created for gas–liquid flow and a method of calculating gas fractions was established. 相似文献
993.
深入分析了目前城市滨湖地区发展中存在的主要问题,结合岳阳中航·翡翠湾规划设计实例,提出了一种基于国情较为合理的滨湖住区形态,改善了人居环境,使滨湖景观更加完美。 相似文献
994.
以鄂尔多斯盆地靖边气田A井区为例,采用单因素相关分析和数值模拟方法,对比研究了井网控制程度、储层物性及地层废弃压力对气藏采收率影响及其主次关系。结果表明,井网控制程度是影响采收率的首要因素,井网控制程度每增加10%,采收率提高8.5%;渗透率是影响采收率的重要因素,渗透率每增加10%,采收率平均增加6%;废弃压力对采收率亦有较大影响,废弃压力每降低10%,采收率可提高1.6%。三者对采收率影响综合排序为:井网控制程度>储层物性>废弃压力。分析认为,渗透率是储层固有属性,很难从根本改变;而废弃压力受井口外输压力和增压开采成本制约,降低幅度有限。因此,优化井网及增加井网控制程度是提高气藏采收率的有效途径。研究成果具有实践意义,可为改进气田开发方式和提高气藏采收率提供参考。 相似文献
995.
In view of the importance of gas-liquid two-phase spiral flow and the few research reports at home and abroad,the gas-liquid two-phase spiral flow patterns have been researched in a horizontal pipe with different parameters investigated by means of observation and a high-speed camera.Since the appearance of spiral flow makes the distribution of twophase flow more complicated,the flow patterns appearing in the experiments were divided into the Spiral Wavy Stratified Flow(SWS),the Spiral Bubble Flow(SB),the Spiral Slug Flow(SS),the Spiral Linear Flow(SL),the Spiral Axial Flow(SA),and the Spiral Dispersed Flow(SD) by the observations and with reference to the predecessors’ research achievements.A flow pattern map has been drawn up.The influence of velocity,vane angle and vane area on flow pattern conversion boundary and pressure drop has been studied,with a solid foundation laid for the future research work. 相似文献
996.
Yu Duan Minghui Li Zhaodong Niu Peiliang Jing Zengping Chen 《Journal of Modern Optics》2018,65(1):85-97
In most large field of view (FOV) observations, the distortion problem is inevitably and significantly more serious than in small FOV ones. In the circumstances, many traditional star identification approaches are not able to efficiently identify stars any more. In order to deal with this problem, we put forward a star identification method that is less sensitive to distortion. The method first processes stars in the central area of the image, using traditional identification logic, and then applies the region growing strategy to enlarge the identified regions iteratively until the entire image is covered. The performance of the new scheme is analysed in the presence of both simulated data and real data. The results show that the proposed algorithm has the advantage of speed, and the strategy of regional extension can efficiently identify stars in large FOV images compared with other existing algorithms. 相似文献
997.
为了避免装饰工程施工中因排砖方法不正确影响工程观感效果,对外墙面砖、室内地板砖、卫生间地板砖的排砖方法进行阐述,以供装饰工程施工人员参考借鉴。 相似文献
998.
江南园林昆曲观演空间是园林空间与昆曲艺术长期相互作用的产物,具有极高的文化、艺术和研究价值。文章选择苏州留园内的三处昆曲观演空间,利用文献阅读、实地测绘、场景复原等方法,从尺度意境、空间组合、视线组织和昆曲活动等方面进行分析和解读,探索了园林空间与昆曲活动的具体作用机制。留园内三处昆曲观演空间的物理特征与昆曲活动各有特色,呈现出不同的相互作用关系;昆曲活动和三处昆曲观演空间都具有极高的匹配度,通过长期的磨合形成一致的风格趋向,构成了具有鲜明时代特征的昆曲观演空间。 相似文献
999.
Emmanouil D. Protonotarios Buzz Baum Alan Johnston Ginger L. Hunter Lewis D. Griffin 《Journal of the Royal Society Interface》2014,11(99)
Human observers readily make judgements about the degree of order in planar arrangements of points (point patterns). Here, based on pairwise ranking of 20 point patterns by degree of order, we have been able to show that judgements of order are highly consistent across individuals and the dimension of order has an interval scale structure spanning roughly 10 just-notable-differences (jnd) between disorder and order. We describe a geometric algorithm that estimates order to an accuracy of half a jnd by quantifying the variability of the size and shape of spaces between points. The algorithm is 70% more accurate than the best available measures. By anchoring the output of the algorithm so that Poisson point processes score on average 0, perfect lattices score 10 and unit steps correspond closely to jnds, we construct an absolute interval scale of order. We demonstrate its utility in biology by using this scale to quantify order during the development of the pattern of bristles on the dorsal thorax of the fruit fly. 相似文献
1000.
Internal preference mapping (IPM) and Landscape Segmentation Analysis® (LSA) are two techniques broadly used to unfold consumers’ overall product liking ratings and create spatial maps that will provide further insights on consumers’ preferences. IPM is based on a vector model while LSA involves an ideal point model. Through a simulation and the analysis of 27 market research data sets, it is shown that IPM consistently creates a hedonic dimension that prevents the identification of satiety prone attributes (intensities higher or lower than a optimal level being disliked by the consumers) on that dimension. As a result, subsequent steps taken upon generating an IPM map such as the investigation of drivers of liking, population segmentation and the estimation of optimal product profiles have also a strong likelihood of resulting in distorted results, the level of distortion being dependent on the actual configuration of the underlying structure that IPM tried to uncover. It is also shown that a technique based on ideal points such as LSA does not exhibit this systematic artifact when unfolding liking data. Consequently, sensory scientists and market researchers should use caution when interpreting and using results issued from an internal preference mapping analysis. 相似文献