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991.
The UK Government has committed itself to reducing its carbon dioxide emissions. The challenge of successfully achieving a transition to a sustainable energy system, in the context of the UK's largely privately owned energy industry, rests on the ability of policy makers to encourage and enable the necessary changes or innovation at all levels of the energy system. This paper argues that the UK's current, dominant political paradigm or framework (the regulatory state paradigm (RSP)) and within it, the role of the economic regulator, Ofgem acts as a fundamental block to this challenge. 相似文献
992.
993.
Ann M. Ray James D. Barbour J. Steven McElfresh Jardel A. Moreira Ian Swift Ian M. Wright Alenka ?uni? Robert F. Mitchell Elizabeth E. Graham Ronald L. Alten Jocelyn G. Millar Lawrence M. Hanks 《Journal of chemical ecology》2012,38(9):1151-1158
Recent work suggests that closely related cerambycid species often share pheromone components, or even produce pheromone blends of identical composition. However, little is known of the pheromones of species in the subfamily Prioninae. During field bioassays in California, males of three species in the prionine genus Tragosoma were attracted to 2,3-hexanediols, common components of male-produced aggregation pheromones of beetles in the subfamily Cerambycinae. We report here that the female-produced sex pheromone of Tragosoma depsarium “sp. nov. Laplante” is (2R,3R)-2,3-hexanediol, and provide evidence from field bioassays and electroantennography that the female-produced pheromone of both Tragosoma pilosicorne Casey and T. depsarium “harrisi” LeConte may be (2S,3R)-2,3-hexanediol. Sexual dimorphism in the sculpting of the prothorax suggests that the pheromone glands are located in the prothorax of females. This is the second sex attractant pheromone structure identified from the subfamily Prioninae, and our results provide further evidence of pheromonal parsimony within the Cerambycidae, in this case extending across both subfamily and gender lines. 相似文献
994.
995.
Green C.D. Vaughan A.S. Mitchell G.R. Liu T. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2008,15(1):134-143
The influence of a montmorillonite (MMT) nanoclay, functionalized with dimethyl-di(hydrogenated tallow) quaternary amine, on structural evolution and electrical characteristics of a designed polyethylene system has been studied. Samples were prepared by mixing a polyethylene/MMT masterbatch into a matrix system containing 10% high density polyethylene and 90% low density polyethylene using an extruder; X-ray diffraction results suggest good dispersion and exfoliation, as no basal peak was observed. The introduction of this MMT system was found to result in little disruption of the polymer crystallization process and analysis of the crystallization kinetics of the matrix polymer suggests that it interacts only weakly with the incorporated MMT. This is in sharp contrast to our previous studies of a differently functionalized MMT system. Electrically, this combination of highly dispersed MMT within a weakly interacting polymer matrix results in a significant enhancement in short-term breakdown strength. However, this is accompanied by a massive increase in dielectric loss. 相似文献
996.
A robust finding in humans and animals is that intermixed exposure to 2 similar stimuli (AX/BX) results in better discriminability of those stimuli on test than does exposure to 2 equally similar stimuli in 2 separate blocks (CX_DX)--the intermixed-blocked effect. This intermixed-blocked effect may be an example of the superiority of spaced over massed practice; in the intermixed, but not the blocked exposure regime, each presentation of a given stimulus (e.g., AX) is separated from the next by the presentation of its partner (BX). Two experiments with human participants replicated the intermixed-blocked effect and showed that the effect was not due to the spacing of exposure trials. A mechanism for the intermixed-blocked effect is proposed, which combines theories from associative learning and memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
We show that smoothing of multiaffine surfaces that are generated by simulating a crosslinked polymer gel by a frustrated, triangular network of springs of random equilibrium lengths [G. M. Buendía, S. J. Mitchell, P. A. Rikvold, Phys. Rev. E, 66 (2002) 046119] changes the scaling behavior of the surfaces such that they become self-affine. The self-affine behavior is consistent with recent atomic force microscopy (AFM) studies of the surface structure of crosslinked polymer gels into which voids are introduced through templating by surfactant micelles [M. Chakrapani, S. J. Mitchell, D. H. Van Winkle, P. A. Rikvold, J. Colloid Interface Sci. 258 (2003) 186]. The smoothing process mimics the effect of the AFM tip that tends to flatten the soft gel surfaces. Both the experimental and the simulated surfaces have a non-trivial scaling behavior on small length scales, with a crossover to scale-independent behavior on large scales. 相似文献
998.
Pilotti Maura; Balota David A.; Sommers Mitchell; Khurshid Ayesha 《Canadian Metallurgical Quarterly》2000,15(2):313
In 3 experiments, auditory massed repetition was used to examine age-related differences in habituation by means of the verbal transformation paradigm. Participants heard 10 words (5 high frequency and 5 low frequency), each presented 180 times, and they reported perceived changes in the repeated words (verbal transformations). In these experiments, older adults reported fewer illusory percepts than young adults. Older adults' loss of auditory acuity and slowing of processing, stimulus degradation (in young adults), and instructions biasing the report of these illusory percepts did not account for the fewer illusory percepts reported by the older adults. These findings suggest that older adults' reduced susceptibility to habituation arises from centrally located declines in the transmission of information within the word recognition pathway. The discussion focuses on the implications that these age-related declines may have on word identification during on-line speech perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Brenda J. Little Patricia Wagner James S. Maki Marianne Walch Ralph Mitchell 《The Journal of Adhesion》2013,89(3):187-210
Starvation, growth phase, and carbon source influenced bacterial cell surface hydrophobicity. Both the number and kind of microorganisms that colonized metal surfaces depended on the type of metal and the presence of an imposed electrical potential. No significant differences in attachment and growth of a pure culture were observed when metal surfaces were dipped in an exogenous energy source. The chemical composition of naturally occurring adsorbed organic films on metal surfaces was shown to be independent of surface composition and polarization. 相似文献
1000.
Isothermal differential scanning calorimetry (DSC) was used to study the crystallization kinetics of amorphous lactose at 3 moisture contents. Each sample was heated to several temperatures between Tg and Tm. After subtraction of an induction time, the Avrami equation was used to model the data and a Lauritzen-Hoffman like expression used to fit the crystallization rates between Tg and Tm. The highest Tm/Tg ratio and crystallization rate were observed for the sample containing the most moisture. Conversely the lowest Tm/Tg ratio and crystallization rate were observed for the sample containing the least moisture. Evidence for multiple transitions was seen. The Avrami equation may not be the best way to model such data. 相似文献