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51.
We present an approach to similarity‐based retrieval from knowledge bases that takes into account both the structure and semantics of knowledge base fragments. Those fragments, or analogues, are represented as sparse binary vectors that allow a computationally efficient estimation of structural and semantic similarity by the vector dot product. We present the representation scheme and experimental results for the knowledge base that was previously used for testing of leading analogical retrieval models MAC/FAC and ARCS. The experiments show that the proposed single‐stage approach provides results compatible with or better than the results of two‐stage models MAC/FAC and ARCS in terms of recall and precision. We argue that the proposed representation scheme is useful for large‐scale knowledge bases and free‐structured database applications. 相似文献
52.
G. K. Kostyuk M. M. Sergeev M. A. Girsova E. B. Yakovlev I. N. Anfimova T. V. Antropova 《Glass Physics and Chemistry》2014,40(4):415-420
The principles of the formation of modified areas of a spherical shape and complex structure in porous glass plates doped by silver and copper halides under the continuous radiation of a fiber laser focused inside the plate have been formulated. The results of the study of the obtained modified areas are given. 相似文献
53.
S. S. Voznesenskiy A. A. Sergeev A. Yu. Mironenko S. Yu. Bratskaya V. A. Kolchinskiy 《Technical Physics Letters》2012,38(3):228-230
We have measured the optical characteristics of thin films based on various ion forms of chitosan and studied their mutual
correlation. Using the spectral ellipsometry and mode spectroscopy techniques, it has been established that the optical characteristics
of chitosan depend on the relative humidity (RH) of the ambient medium. All samples are characterized by threshold RH values, at which the optical characteristics exhibit a change. The obtained data allow chitosan to be classified as a promising
sensor material with the optical properties controlled by relative humidity of the ambient medium. 相似文献
54.
Dirk J. A. Senden Tom A. P. Engels Serge H. M. S?ntjens Leon E. Govaert 《Journal of Materials Science》2012,47(16):6043-6046
Polycarbonate is known to suffer from dramatic reductions in ductility upon exposure to hot, humid environments, such as during steam sterilization. Two phenomena have been proposed to be the main causes of this embrittlement: hydrolysis and microcavity formation. The present study focuses on a third phenomenon, whose contribution to the embrittlement has until now been considered insignificant: (physical) aging. By studying the influence of steam sterilization on the tensile deformation behavior of polycarbonate, it is shown that aging actually is one of the dominant factors in the embrittlement. 相似文献
55.
56.
Emmanuel Creusé Patrick Dular Serge Nicaise 《Computers & Mathematics with Applications》2019,77(6):1563-1582
In this paper, we deal with some magnetostatic models considered in vector potential formulations and solved by a Finite Element solver. In order to ensure the uniqueness of the solution, a gauge condition has to be imposed, and several possibilities occur. Moreover, the source term has to be correctly defined to ensure a physically admissible solution. We show the equivalence between some of these choices for several kinds of boundary conditions. Moreover, we highlight their characteristic behaviors on some numerical benchmarks to illustrate our theoretical results. 相似文献
57.
58.
Serge Maillard 《钟表》2018,(3)
正为了充分认识中国当前翻天覆地的变化对制表业所产生的深远影响,我们不妨先退一步,来了解一下中国正在进行深层次的改革。不难发现,钟表购买行为正受到一股爱国浪潮的影响。我们先来看一组数据:今年全球前10大集装箱港口,中国就占了七席;而中国政府还计划在未来5年内对新「丝绸之路」沿线国家投资9000亿美元。在北京邻省,一个新的科技和经济中心正在兴起;而在中国最富有的广东省,也有不少城市搭上了这趟高速发展的快车。 相似文献
59.
60.
Amélie Deglaire Caroline Méjean Katia Castetbon Emmanuelle Kesse-Guyot Christine Urbano Serge Hercberg Pascal Schlich 《Food quality and preference》2012,23(2):110-124
Liking for a sweet, salty or fatty diet may induce overconsumption of simple carbohydrates, sodium or lipids. Measuring overall liking of the corresponding sensory sensations contributes to understanding the determinants of dietary behaviours. However, no standardized validated questionnaire assaying these sensations is currently available. In the present study, we developed a web-based questionnaire, “PrefQuest”, which measures recalled liking for the following four sensations: salt, fat and salt, sweet, fat and sweet. PrefQuest included four types of items: (1) liking for sweet, fatty-sweet and fatty-salty foods, (2) preferences in the level of seasoning by adding salt, sweeteners, or fat, (3) preferences for types of dishes in a restaurant menu and (4) overall questions about sweet-, salt- and fat-related behaviours. A development study (n = 198) demonstrated that PrefQuest was feasible, well-perceived, only lasted about 20 min and that items were repeatable (overall mean intra-class correlation coefficient: 0.77, SD 0.08). Construct validity was then evaluated on a larger population sample (n = 47 803). The underlying structure within each of the four sensations was determined by exploratory factor analysis and then internally validated by confirmatory factor analysis. After a selection of the most relevant items, the salt, fat-and-salt, sweet, and fat-and-sweet scales exhibited a theoretically meaningful factor structure, unidimensional for the salt scale and with interrelated sub-dimensions for the sweet, fat-and-salt, and fat-and-sweet scales. Based on the fat-and-sweet and fat-and-salt scales, a fat model was also unveiled. For each factor, internal consistency as well as convergent and divergent validities were demonstrated. Overall, PrefQuest is an internally valid and original tool that can be used to assay recalled liking for sweet, salt, and fat considered altogether or separately as fat and salt or fat and sweet, and can be applied to large population surveys. 相似文献