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991.
992.
中国大陆地区沉积盆地的热状况、热历史和生烃史 总被引:1,自引:1,他引:0
1. Introduction The thermal regime or thermal background is an important tool for revealing the geodynamic processes of the continental lithosphere and establishing the onset of the generation of hydrocarbons from source rocks in sedimentary basins (Chapm… 相似文献
993.
并行操作系统的现状与发展趋势 总被引:5,自引:0,他引:5
本从操作系统的发展史,当前的发展状态,未来的发展趋势以及技术研究的几个热点等方面进行了阐述。 相似文献
994.
准噶尔盆地车排子地区油气成藏期次研究 总被引:2,自引:1,他引:1
车排子地区位于准噶尔盆地西部,在不同层位发现众多稠油及油气显示,并发现了具有工业价值的轻质油,因此,研究该区的油气成藏期次,对车排子地区的勘探突破具有重要的意义。该区原油按地化特征的差异可分为3类,油源分析表明它们分别来自中下侏罗统混合型烃源岩、中二叠统烃源岩以及中二叠统和中下侏罗统腐泥型烃源岩的混源。在油源分析和烃源岩生烃史模拟的基础上,结合准噶尔盆地及车排子地区构造发育史,将车排子地区油气充注分为4期,即侏罗纪至早白垩世来自中二叠统烃源岩的油气充注成藏、中晚白垩世以来早期形成的稠油发生再次运移形成次生稠油油藏、新近纪早期来自中下侏罗统烃源岩早期生成的少量油气在中生界、古近系和新近系地层充注成藏以及新近纪中晚期至第四纪来自中下侏罗统烃源岩中晚期生成的油气在新近系地层充注成藏。 相似文献
995.
Gustaf Östberg 《AI & Society》1989,3(3):220-228
During the last two decades considerable efforts have been made to develop computerized data systems for engineering materials. The results have not come up to the expectations of systems that can be used by designers for selecting of materials. Some factors have been recognized as responsible for the slow progress. It has proved difficult, however, for those involved in this development to make use of such information about the systems in question. Conflicts have occurred between different parties involved. It now seems that too little attention has been paid to the historical background of knowledge and systems related to civiliziation and society. A recently published review of world history from the point of view of the emergence of information technology has provided a basis for some considerations about the nature and roles of data systems. It can be shown that certain activities or features characterize each period of civilization and the development of computers and computerization should be considered as part of this sequence. The same is true for the world history of thinking and knowledge. In the present paper these historical considerations are combined with the observation that in their thinking and perception of ideas people appear to carry with them traditions from the past in varying degrees. Hence differences of opinion about the nature and roles of materials data systems may be explained by differences in the imprint of historical developments on people's ideas. In order to apply this lesson to the development of materials data systems, one has to learn also from the varying interpretations of world history that have been written through the ages. The best approach will probably be incremental and pragmatic rather than holistic and synoptic. 相似文献
996.
历代皇家园林的内容、规模及地位是有差别的,因之管理机构的设置也各有不同。反之,从管理机构的组织,又可以探索当时皇家园林的地位、内容和作用。 相似文献
997.
Reviews the book, Applications of personal construct theory edited by J. Adams-Webber and J. C. Mancuso (1983). The 24 chapters of this volume are a selection from papers presented at the Fourth International Congress on Personal Construct Psychology (PCP) held in 1981. The title of the volume is perhaps misleading, as there are three discernible motifs in this varied assortment of offerings. These can be identified as those papers dealing primarily with theoretical issues, those concerned with the history of the theory and the man who developed it (George Kelly), and those that focus on applications of the theory. It is clear that ten chapters are theoretical, including the first nine and Bannister's concluding chapter on the self. If I were to assume that these efforts are representative of the development of PCP, my judgment would be that little important change in Kelly's ideas has occurred over the years. It is not easy to say why this is so, although the fact that Kelly died before he might have revised aspects of his theory has to be considered. Overall, however, the conceptual advances have a pallid quality and the occasional adulatory echoing of the master is disconcerting. Of the 11 or so empirical and applied chapters, a number point in useful and interesting directions. Several papers deal with PCP in relation to schizophrenic thought disorder, depression, chronic illness, anorexia nervosa, and obsessive neurosis. Neimeyer's chapter on sociohistorical influences in the development of PCP affords an opportunity to reflect upon the past, present, and future of Kelly's ideas--including the trend toward integration with other schools of thought despite Kelly's well-known resistance to direct comparison with other kindred theories. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
D. I. H. Johnstone 《Journal of the Institute of Brewing》1986,92(6):529-536
The food can had its origins in the early nineteenth century and underwent continuous and substantial development prior to its introduction as a beer container in the nineteen thirties. Since then methods of manufacture have changed considerably, always with the aim of increasing efficiency and reducing cost. The modern beer can is a cheap, attractive and lightweight container requiring strict quality control to maintain the necessary high standards. 相似文献
999.
Tom Mulvey 《Journal of microscopy》1989,155(3):327-338
The unpredictable development of the electron microscope is reviewed in the context of the 150th Anniversary of the Royal Microscopical Society. Abbe convinced himself that an electron microscope could never be constructed. Later, J. J. Thomson established the minute corpuscular nature of the electron and Rutherford realized that such beams can reveal the nature of the atom; his student H. G. Moseley invented electron probe analysis, while looking for X-ray spectra, but the technique did not seem very practical. G. P. Thomson invented the electron diffraction camera, but it was of limited use without an electron lens. In 1931, Knoll and Ruska built a two-stage TEM with magnetic lenses and understood where Abbe went wrong. Although Ernst Ruska surpassed the resolving power of the light microscope in 1933, the first commercial TEM was manufactured in the U.K., leading to many further commercial developments. The realization of a digital computer with a stored program, now indispensible in microscopy, was also achieved first in the U.K. Gabor's electron beam holography, invented in Rugby in 1949, was not a challenge to the conventional TEM at first, but recently atomic resolution holography has been achieved in Abbe's native country, using a digital computer to process the hologram, ironically making use of the very principles laid down by Abbe in the last century for the light microscope. 相似文献
1000.
单一模型EnKF法更新油藏模型的探讨 总被引:2,自引:2,他引:0
近年来,人们开始利用集合卡尔曼滤波(EnKF)进行自动历史拟合,更新油藏模型。实验证明EnKF方法是一种有效的方法。EnKF方法要求一组初始实现,但是在实际应用中往往只有一个油藏或地质模型,这使得直接利用EnKF进行历史拟合,更新油藏模型比较困难。为此,提出了一种由一个模型派生出多个模型来满足EnKF基本要求的随机导航点方法,并试验在尽量少的模型条件下,利用EnKF更新油藏模型。模型实验表明,利用随机点抽样派生出多个模型,再利用EnKF可以实现单一模型更新,最终取得的模型与参考模型具有较好的一致性。 相似文献