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81.
Ignition of the external combustible elements of a building is one of the key factors leading to house loss in bushfires. Timber elements contain moisture that migrates into and out from the timber surface, depending on the surrounding ambient conditions. In extreme hot and dry conditions, such as those associated with severe bushfire weather, the moisture contents (MCs) in building timbers can drop well below the normal levels. In this paper, we not only qualify a methodology to assess the likely MCs of timbers under typical bushfire conditions, but also quantify the low levels of moisture that can be expected for the climatic conditions experienced in Melbourne—one of Australia's bushfire‐prone regions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
82.
The monitoring of production line availability on a day-to-day basis and for continuous improvement is approached from a control charting point of view. Control limits are developed along with the length of time between monitoring periods to control accuracy. This provides a convenient way to monitor the availability measure at any desired level of accuracy. 相似文献
83.
Chan-Hee Park Tae-Hyung Kim Do-Hee Lee Leonard D. Tijing Mi-Hwa Yu Sang-Don Moon Cheol Sang Kim 《Metallurgical and Materials Transactions A》2012,43(9):3006-3010
We report here for the first time the use of magnetic polishing to improve the surface finish of titanium-nickel (TiNi) stents for better performance. We investigated the effects of polishing time and rotational speed on the average surface roughness, surface chemical contents, and push-out load of stents. The magnetically polished stents show a decrease of 2.3 to 17.9?pct in surface roughness and a lower push-out load for stent deployment from the catheter. 相似文献
84.
85.
Chiarello Christine; Welcome Suzanne E.; Halderman Laura K.; Towler Stephen; Julagay Janelle; Otto Ronald; Leonard Christiana M. 《Canadian Metallurgical Quarterly》2009,23(2):210
The authors report findings of a large-scale, multitask investigation of sex differences in both structural asymmetries and lateralization of word reading. Two hundred participants were tested in eight divided visual field lexical tasks, and each received a structural magnetic resonance imaging scan. The authors examined whether there was evidence for sex differences in overall measures of neuroanatomical and behavioral lateralization, in specific language tasks and brain regions, and in variation in asymmetry within and across tasks and brain regions. There was very little evidence for sex differences on any behavioral measure. The few indications of sex differences in the current report accounted for 2% or less of the individual variation in asymmetry and could not be replicated in independent subsamples. No sex differences were observed in the asymmetry of structures in Broca's and Wernicke's areas such as pars triangularis, pars opercularis, the planum temporale, planum parietale, or Heschl's gyrus. There were also no sex differences in the variability of neuroanatomical asymmetries within or between brain regions. However, a significant relationship between planum temporale and behavioral asymmetry was restricted to men. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Huizhen Li Ran Guo Yuhai Liu Shaoxuan Liu Edyta Proniewicz Leonard M. Proniewicz Ying Zhao Yizhuang Xu Jinguang Wu 《应用聚合物科学杂志》2015,132(35)
The effect of thermal treatment over a wide range of temperature (130–280°C) on the crystallization behavior of nylon 6 was studied by using DSC, FTIR, and polarized light microscope equipped with a hot stage. The crystallization and the subsequent melting behavior of the nylon 6 samples treated at different temperatures (Ts) were classified into four types. When Ts was higher than 236°C or lower than 213°C, the crystallization behavior of nylon 6 was insensitive to the variation of Ts. When Ts was in the range of 213–235°C, the crystallization behavior was sensitive to the change of Ts. The polarized light microscopic experiments have demonstrated that a large amount of tiny ordered nylon 6 segments/cluster persisted when nylon 6 film are heated to 231°C. Consequently, the fastest crystallization speed was observed. As Ts was between 214 and 223°C, both the Tm and the ΔHm were higher than those of the nylon 6 samples treated at other temperature. The polarized light microscopic investigations have also demonstrated that molten nylon 6 crystallizes by using the un‐molten nylon 6 crystals as nucleation center at 220°C. Crystallization at higher temperature produces nylon 6 with thicker crystalline lamella. The above results are helpful for rational design of thermal treatment procedure to obtain nylon 6 with different crystalline features. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42413. 相似文献
87.
Leonard Heumann 《Journal of the American Planning Association. American Planning Association》2013,79(2):252-253
A problem in applying benefit-cost analysis to planning issues is the difficulty of imputing values to public goods like water quality. During the past thirty years, the contingent valuation (CV) survey method has been institutionalized as a technique for valuing these types of goods. This article traces the development of the method and summarizes recent federal guidelines. Examples from three recent studies, involving willingness to pay for nonpoint-source pollution controls, are used to illustrate issues about the technique. Considerations for planners who must undertake or evaluate CV studies are discussed. 相似文献
88.
Leonard R. Bachman 《Building Research & Information》2013,41(6):752-760
Definitions and perceptions of professionalism are continually challenged and transformed by public need, government interaction and institutional organizations. When the goals of those three entities are focused on near-term results, this poses a significant threat to the integrity, value and relevance of professional services. When the individual and corporate professional's profit margin, corporate shareholder responsibility and news media sensationalism are factored in, this short-termism dynamic is greatly magnified. Built environment professions are seen as particularly vulnerable to this threat, given that investments in buildings and infrastructure have long-life and high-performance service expectations. This commentary responds to the Building Research & Information special issue entitled ‘New Professionalism’ (2013, volume 40, number 1) and situates the predicament of built environment professionals within an emerging historical transition: that of the post-industrial information society with its characteristic knowledge workers and cybernetic bases of production. Long-term virtues of the built environment mission such as sustainability, public good and evidence-based design are shown to be reflections of the transition from industrial era short-termism to post-industrial systemic foresight. This commentary supplements the special issue papers with a discussion on the broader academy's potential role in breaking the stranglehold of contemporary short-termism in the built environment professions. 相似文献
89.
Leonard K. Eaton 《The Journal of Architecture》2013,18(4):315-346
This paper traces the development of Frank Lloyd Wright's ideas on the place of the concrete column and slab in architecture. It deals with his first employment of the slab at Unity Temple (Oak Park, 1904) and his use of the form in residential projects during the next few years. It surveys American literature on concrete construction and briefly analyses the contribution of Claude A.P. Turner and the employment of the Turner system in two Chicago buildings that Wright would have known. It discusses his project for the San Francisco Call (1912) and the use of the Barton system in the Richland Center warehouse for A.D. German (1915). It further discusses his first probable knowledge of the more sophisticated concrete slabs of Maillart, published in 1926, and of Maillart's invention of a proto lily-pad capital. This capital is also to be seen in Wright's champagne glass designed for Leerdam (1930) and in his project for the Salem Capitol Journal of 1931. Finally it is argued that the much admired lily-pad columns at the Johnson Wax office building (Racine, 1937-39) are really a series of three-hinged bents rather than shell construction. 相似文献
90.
现代光学耦合器的核心是输入端的LED和输出端的光电探测器.它们被绝缘的光传导介质隔开. 相似文献