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981.
分析比较了一栋高层办公大楼采用常规空调和冰蓄冷空调方案的技术可行性,造价,运行电费诸方面,认为在峰谷电价比为2:1的情况下由于电费的节省冰蓄冷空调超出常规空调的造价部分回收期为3a。 相似文献
982.
冰蓄冷研究的现状与展望 总被引:15,自引:2,他引:13
对冰蓄冷技术的研究和开发现状作了综述,讨论了其中尚未解决的一些问题及技术难点,展望了近期冰蓄冷研究和开发的走向。 相似文献
983.
K. Huemer G. Wolf A. Sormann G. Frank 《BHM Berg- und Hüttenm?nnische Monatshefte》2005,150(7):237-242
The treatment of liquid steel with calcium is an often used practice, if the melt has been killed with aluminium. Thus high melting aluminium oxides are being modified to calcium aluminates with a lower melting point. This improves the castability in the continuous casting process. Therefore experiments have been carried out at Voestalpine Stahl Donawitz to determine the effects of a calcium treatment on the inclusion composition and morphology Tests of the steel purity and SEM/EDX-analyses of nonmetallic inclusions have been carried out. Main interest of the investigations were the influence of a high sulphur content in the melt and bigger amounts of calcium. By means of the results, the formation of inclusions (calcium aluminates, calcium sulphides) could be reproduced and influences on the steel purity could be shown. 相似文献
984.
The neuronal mechanism of associative learning and memory storage operating in the central nervous system of the terrestrial mollusc Limax maximus has been modeled as a computer simulation called LIMAX (A. Gelperin et al [1985]). One test of the LIMAX model is to determine whether Limax can learn to avoid a compound stimulus composed of the mixture of two innately attractive odors without simultaneously learning an aversion to the individual odors comprising the mixture. We found that Limax can learn a strong aversion to odor A?+?B while odor A and odor B remain strongly attractive when presented individually. This result led us to reexamine the sensory coding scheme used in the LIMAX model to represent stimulus mixtures, and it suggests neurophysiological experiments to examine the actual chemosensory coding scheme used by Limax. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
985.
Alan M. Allgeier Denise Andersen Michael D. Bartberger Emilio E. Bunel Robert D. Larsen Pingli Liu Thomas Storz Jason S. Tedrow 《Topics in Catalysis》2014,57(17-20):1335-1341
To overcome stability issues associated with the use of an aldehyde in a catalytic reductive amination reaction, a cyclic ketolactol (ω-hydroxylactone) was employed as an aldehyde surrogate to form a γ-aminoacid. The reaction proceeded most favorably over a Pt/C catalyst. The thermodynamics of each step were evaluated using density functional theory calculations, which correctly predicted the dominance of the ring-closed lactol reactant, yet suggested a preference for a ring-opened iminium intermediate upon the initial, slightly endoergic addition of amine substrate. Exoergic hydrogenation of this intermediate provided the thermodynamic driving force for the overall transformation. During development, the reaction was observed to depend significantly on the volumetric gas to liquid mass transfer coefficient (kLa) and this parameter was optimized to ensure successful scale up in a 400 L stirred tank reactor. 相似文献
986.
Alexandru I. Petrisor Sandra Szyjka Tomohiro Kawaguchi Pieter T. Visscher Robert Sean Norman Alan W. Decho 《International journal of molecular sciences》2014,15(1):850-877
Microspatial arrangements of sulfate-reducing microorganisms (SRM) in surface microbial mats (~1.5 mm) forming open marine stromatolites were investigated. Previous research revealed three different mat types associated with these stromatolites, each with a unique petrographic signature. Here we focused on comparing “non-lithifying” (Type-1) and “lithifying” (Type-2) mats. Our results revealed three major trends: (1) Molecular typing using the dsrA probe revealed a shift in the SRM community composition between Type-1 and Type-2 mats. Fluorescence in-situ hybridization (FISH) coupled to confocal scanning-laser microscopy (CSLM)-based image analyses, and 35SO4
2−-silver foil patterns showed that SRM were present in surfaces of both mat types, but in significantly (p < 0.05) higher abundances in Type-2 mats. Over 85% of SRM cells in the top 0.5 mm of Type-2 mats were contained in a dense 130 μm thick horizontal layer comprised of clusters of varying sizes; (2) Microspatial mapping revealed that locations of SRM and CaCO3 precipitation were significantly correlated (p < 0.05); (3) Extracts from Type-2 mats contained acylhomoserine-lactones (C4-, C6-, oxo-C6 C7-, C8-, C10-, C12-, C14-AHLs) involved in cell-cell communication. Similar AHLs were produced by SRM mat-isolates. These trends suggest that development of a microspatially-organized SRM community is closely-associated with the hallmark transition of stromatolite surface mats from a non-lithifying to a lithifying state. 相似文献
987.
Serving regional demand in facility location 总被引:1,自引:0,他引:1
Location modelling is employed in urban and regional planning to site facilities that provide services of some sort. Issues to be considered usually include the number of facilities to locate, where to site those facilities and how demand is to be served. Given the geographic nature of location problems, a key issue is how to represent facilities and demand in geographic space. Traditionally, spatial abstraction as discrete demand is assumed as it simplifies model formulation and reduces computational complexity. However, errors in derived solutions are likely not negligible, especially when demand varies continuously across a region. This paper discusses a single facility location problem that considers demand to be continuously distributed and allows a facility to be located anywhere in space, the continuous Weber problem. An approach for dealing with continuous demand is proposed that is integrated through geographical information system (GIS) functionality. Empirical results highlight the advantages of the developed approach and the importance of solution integration with GIS. 相似文献
988.
989.
In recent years, the Triple Helix model has identified feasible approaches to measuring relations among universities, industries, and governments. Results have been extended to different databases, regions, and perspectives. This paper explores how bibliometrics and text mining can inform Triple Helix analyses. It engages Competitive Technical Intelligence concepts and methods for studies of Newly Emerging Science & Technology (NEST) in support of technology management and policy. A semantic TRIZ approach is used to assess NEST innovation patterns by associating topics (using noun phrases to address subjects and objects) and actions (via verbs). We then classify these innovation patterns by the dominant categories of origination: Academy, Industry, or Government. We then use TRIZ tags and benchmarks to locate NEST progress using Technology Roadmapping. Triple Helix inferences can then be related to the visualized patterns. We demonstrate these analyses via a case study for dye-sensitized solar cells. 相似文献
990.
Research that integrates the social and natural sciences is vital to address many societal challenges, yet is difficult to arrange, conduct, and disseminate. This paper compares diffusion of the research supported by a unique U.S. National Science Foundation program on Human and Social Dynamics (“HSD”) with a matched group of heavily cited papers. We offer a measure of the distance of cites between the Web of Science Category (“WoSC”) in which a publication appears and the WoSC of the journal citing it, and find that HSD publications are cited more distantly than are comparison publications. We provide another measure—citation velocity—finding that HSD publications are cited with similar lag times as are the comparison papers. These basic citation distance and velocity measures enrich analyses of research knowledge diffusion patterns. 相似文献