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101.
Comments on a prior discussion of animal rights (see record 2009-05603-005) by Gordon G. Gallup, Jr. Gallup asserted that there are no inherent rights; they are inventions of the human mind. Thus, animals only have rights to the extent that we say they do. In this comment, Andrew N. Rowan posits that there is more universal agreement as to why some beings have certain rights (e.g. the right to life, or the weaker right not to be caused unnecessary suffering) than Gallup credits. However, even though philosophers have attempted to develop consistent arguments to underpin a "rights" theory, there are still many problems. Some of these problems are briefly touched upon here. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
W.R. Dixon R.S. Storey W.F. Davidson 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1985,12(2):304-310
Tritium implanted Si(Li) detectors suffer from the effects of radiation damage during the implantation. These effects are manifested as a pulse height defect and as a broadening of the response function, and thus cause problems in the determination of the tritium beta end-point energy and in the determination of the electron antineutrino mass from the shape of the spectrum near the end point. We use simple models of the trapping of charge carriers to illustrate some of these problems. 相似文献
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Although database design tools have been developed that attempt to automate (or semiautomate) the design process, these tools do not have the capability to capture common sense knowledge about business applications and store it in a context-specific manner. As a result, they rely on the user to provide a great deal of "trivial" details and do not function as well as a human designer who usually has some general knowledge of how an application might work based on his or her common sense knowledge of the real world. Common sense knowledge could be used by a database design system to validate and improve the quality of an existing design or even generate new designs. This requires that context-specific information about different database design applications be stored and generalized into information about specific application domains (e.g., pharmacy, daycare, hospital, university, manufacturing). Such information should be stored at the appropriate level of generality in a hierarchically structured knowledge base so that it can be inherited by the subdomains below. For this to occur, two types of learning must take place. First, knowledge about a particular application domain that is acquired from specific applications within that domain are generalized into a domain node (e.g., entities, relationships, and attributes from various hospital applications are generalized to a hospital node). This is referred to as within domain learning. Second, the information common to two (or more) related application domain nodes is generalized to a higher-level node; for example, knowledge from the car rental and video rental domains may be generalized to a rental node. This is called across domain learning. This paper presents a methodology for learning across different application domains based on a distance measure. The parameters used in this methodology were refined by testing on a set of representative cases; empirical testing provided further validation 相似文献
106.
JS Magnussen P Chicco AW Palmer DW Mackey M Magee IP Murray G Bautovich K Allman G Storey H van der Wall 《Canadian Metallurgical Quarterly》1997,38(12):1987-1991
Accurate and reproducible reporting of lung scintigraphy is predicated on a sound knowledge of the segmental anatomy of the lungs. A limited amount of hard data exists about the true segmental anatomy of the lungs. A virtual model of human lungs was created using a CT-based dataset and a Monte Carlo simulation technique to examine the optimal projections for the visualization of each segment in the lungs. METHODS: Segmental anatomy of the lungs was modeled using CT, cadaveric lungs and standard anatomical texts. The emission, scatter and attenuation of photons was modeled within these virtual lungs and the surrounding tissues. Single segmental lesions were created in eight projections and submitted for blinded reporting to four experienced nuclear medicine physicians to obtain the best views for each segment. RESULTS: The anterior and posterior oblique projections yielded the best views for 10 of 18 segments, with the laterals contributing four views, the anterior contributing two views and the posterior contributing one view. The majority of basal segments (six of nine) were best seen in the anterior and posterior oblique projections. CONCLUSION: This model overcomes the major problems associated with experimentation in the normal human and has the potential to provide answers to the major problems of scatter, attenuation and "shine-through" in lung scintigraphy. 相似文献
107.
Daryl D. Rowan Jenny J. Dymock Margaret A. Brimble 《Journal of chemical ecology》1990,16(5):1683-1695
Peramine, a pyrrolopyrazine alkaloid produced by the fungal endophyte of perennial ryegrassAcremonium lolii, deterred the feeding of both adults and larvae of the graminacious herbivore, the Argentine stem weevil (Listronotus bonariensis), at 0.1 g/g and 10 g/g, respectively. In a no-choice test fewer stem weevil larvae fed and developed on diet containing as little as 2 g/g peramine. The proportion of larvae which did not develop beyond the first instar was higher on diet containing peramine and appeared to be due to a higher proportion of larvae which did not feed. For larvae which fed on the peramine-containing diet, feeding scores and times to pupation were not significantly different from those of controls. A number of simple peramine analogues showed feeding-deterrent activity against adult weevils, indicating the importance of the pyrrolopyrazine ring system of peramine in determining feeding-deterrent activity. 相似文献
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Yousef Mohajer Dinesh Tyagi Garth L. Wilkes Robson F. Storey Joseph P. Kennedy 《Polymer Bulletin》1982,8(2-4):47-54
Three-arm star polyisobutylene ionomers (¯Mn=8800) with terminal SO3
M (M=K or Ca2) groups were synthesized and their mechanical properties investigated. Compression molded films displayed high elongations, i.e., -1000% for Ca2 ionomers with lower values for the K counterions. Strain induced crystallinity was observed at higher elongations. Mechanical properties in general compared favorably with conventional covalently linked rubbery networks and were comparable and in some cases superior to EPDM-based ionomers carrying randomly distributed SO3
M groups.For the first two parts see Proceedings, 28th IUPAC Macromolecular Symposium, Amherst, MA, July 11–16, 1982, p. 905 and 906 相似文献