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71.
In an attempt to develop a desirable resin formulation for spilled oil absorption, segmented polyurethanes of various types and lengths of hard and soft segments have been synthesized and tested for X‐ray diffraction, thermal, mechanical, and dynamic mechanical properties in addition to oil and water absorptions. Significant oil absorption was obtained with ether type polyol of high molecular weight, especially with short hard segments of long‐chain diamines. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2080–2087, 2005 相似文献
72.
KB Avraham T Hasson T Sobe B Balsara JR Testa AB Skvorak CC Morton NG Copeland NA Jenkins 《Canadian Metallurgical Quarterly》1997,6(8):1225-1231
Deafness is the most common form of sensory impairment in humans. Mutations in unconventional myosins have been found to cause deafness in humans and mice. The mouse recessive deafness mutation, Snell's waltzer, contains an intragenic deletion in an unconventional myosin, myosin VI (locus designation, Myo6). The requirement for Myo6 for proper hearing in mice makes this gene an excellent candidate for a human deafness disorder. Here we report the cloning and characterization of the human unconventional myosin VI (locus designation, MYO6) cDNA. The MYO6 gene maps to human chromosome 6q13. The isolation of the human gene makes it now possible to determine if mutations in MYO6 contribute to the pathogenesis of deafness in the human population. 相似文献
73.
74.
Field Tiffany; Healy Brian T.; Goldstein Sheri; Guthertz Moshe 《Canadian Metallurgical Quarterly》1990,26(1):7
Behavior-state matching and synchrony in interactions were assessed in 48 depressed and nondepressed mother–infant dyads when the infants were 3 months old. Attentive/affective behavior states were coded for the infants and mothers on a negative to positive scale. The depressed mothers and their infants matched negative behavior states more often and positive behavior states less often than did the nondepressed dyads. The total percentage of time spent in matching behavior states was less for the depressed than for the nondepressed dyads. Cross-spectral analyses of the mothers' and the infants' behavior-state time series suggested only a trend for greater coherence or synchrony in the interactions of the nondepressed dyads. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
We show that a moving-front solution in a cylindrical shell packed-bed catalyzing a first-order activated reaction may bifurcate into transversal patterns when PeC/PeT<ΔTad/ΔTm, i.e. when the ratio of the mass to heat Pe numbers is smaller than the ratio of the adiabatic to maximal temperature rises. This coincides with the previous condition of transversal patterns to emerge in stationary fronts [PeC/PeT<1 [Viswanathan, G., Bindal, A., Khinast, J., Luss, D., 2005. Stationary transversal hot zones in adiabatic packed-bed reactors. A.I.Ch.E. Journal 51, 3028-3038]] and extends the bifurcations condition to the case of moving fronts. The novel condition cannot be satisfied in a downstream propagating front (ΔTm/ΔTad>1), but for an upstream propagating front (toward the cold reactor inlet) ΔTm/ΔTad<1 and the symmetry breaking can be obtained within a feasible domain of operating conditions (PeC/PeT>1). It was also assumed that the axial and the transversal Pe numbers vary consistently, i.e. κC=PeC⊥/PeC=κT=PeT⊥/PeT. A similar condition was also obtained using a simplified model composed of two 1-D beds with heat and mass exchange between them.Bifurcation diagram showing domains of transversal patterns is constructed using a learning two-bed model. These predictions are verified by direct numerical simulations of the continuous 2-D cylindrical shell model showing various types of moving transversal patterns within a feasible domain of the state parameters with PeC>PeT. In the case of varying ratio (κC≠κT) the pattern domain can be significantly extended toward larger PeC/PeT. 相似文献
76.
A model to convert horizontal solar global radiation to that on a tilted surface is presented. It is based upon a relatively simple model proposed by [Olmo FJ, Vida J, Foyo I, Castro-Diez Y, Alados-Arboledas L. Prediction of global irradiance on inclined surfaces from horizontal global irradiance. Energy 24 (1999) 689–704]., which requires only measurements of horizontal solar radiation but was found to produce significant errors when tested with data from another site. The present model assumes the availability of databases for at least two of the three solar radiation types, viz., global, beam and diffuse. The horizontal global radiation is converted to that on a tilted surface by applying the Olmo model to the diffuse component, whereas the beam component is converted by using the geometrical relationship between the two surfaces. The original Olmo anisotropic radiation correction factor is now assumed to be a function of sky conditions. The solar radiation databases were converted to subsets corresponding to clear, partially cloudy and cloudy sky based upon clearness index values. The three anisotropic correction factors were determined by fitting to a 12-months database. The present model was then tested by applying it to a second database consisting of 24-months not involved in the model development. It was found to give better results than three highly regarded more complex models. 相似文献
77.
We present a simple distributed algorithm that resolves store-and-forward deadlocks in data communication networks. The basic idea of the algorithm is to detect cycles of nodes that may cause store-and-forward deadlocks, and to rotate packets along these cycles. The algorithm uses a fixed amount of storage in each node for its execution, and, under reasonable assumptions upon the routing and packet handling, it ensures that packets that enter the network arrive at their destinations in finite time.Part of this work was done while this author was on sabbatical leave with IBM, Thomas J. Watson Research Center, Yorktown Heights, NY 10598, USA. 相似文献
78.
Ethik in der Medizin - 相似文献
79.
This article includes four experiments in which four criteria for testing the automaticity of coding of temporal order information are examined. Results show that memory for temporal order information is affected by intention to learn, competing task loads, encoding strategy, and subjects' age. The results, which generally hold for memory for absolute, as well as for relative temporal order information, do clarify the somewhat mixed pattern of results in previous studies, which was due, at least in part, to inappropriate testing methodologies. Such results, which are similar to recent tests of automaticity of frequency of occurrence and spatial location information, are at odds with the claim made by several researchers that memory for temporal order information is exclusively mediated by automatic processes. The concept of automaticity and the appropriateness of the testing criteria for it are discussed in light of the current results. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Moshe Favelukis 《Chemical engineering science》2010,65(12):3808-3813
Steady and unsteady mass transfer in the continuous phase around slightly deformed oblate spheroidal drops at low (but not zero) Reynolds numbers was investigated theoretically. Asymptotic analytical solutions for short and long times, at large Peclet numbers, were obtained by the useful equations derived by Lochiel and Calderbank and by Favelukis and Mudunuri for axisymmetric drops of revolution, with the only requirements being the shape of the drop and the tangential velocity at the surface of the drop. As expected, the result, although complicated, represents a small correction to the classical problem of mass transfer around a spherical drop under creeping flow conditions, since the physical problem presented here requires both the Reynolds and the Weber number to be much smaller than one. 相似文献