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41.
This paper describes an experimental investigation of the mechanical behavior of a paper-filled-phenolic laminate widely used
in the electronics industry. Uniaxial tensile tests in three directions, sandwich-beam bending tests to determine the compressive
behavior, and cylindrical-punch punchability tests were conducted. Interesting phenomena observed included difference in tensile
and compressive behavior, consistent crack branching in tension, and strain mismatch during punching.
Based upon a thesis submitted by the first author in partial fulfillment of the requirements for the M.S. degreee in Mechanical
Engineering at the University of Oklahoma, December 1976. 相似文献
42.
CoAPO-5 molecular sieves have been synthesized with glycerol and water as solvent in order to maximize the degree of isomorphous substitution of Co2+ ions in the AFI framework. These CoAPO-5 molecular sieves have been characterized with X-ray diffraction, inductively coupled plasma-atomic emission spectroscopy, scanning electron microscopy, electron microprobe microanalysis, N2 sorption, and UV-visible-NIR-diffuse reflectance spectroscopy techniques. Optimum conditions for the synthesis of Co-rich single-phase and highly crystalline CoAPO-5 molecular sieves were obtained by varying the [Co]:[Al] ratio in the synthesis gel and the synthesis time. It will be shown that highly crystalline hexagonal single-phase CoAPO-5 crystals with a size between 3 and 10 microns and a substitution degree of about 13% can be obtained from a 0.7CoO.0.65Al2O3.1P2O5.1(C2H5)3N.40HOCH2CHOHCH2OH gel at 190 degrees C after 14 days of synthesis. This substitution degree is substantially higher than that for CoAPO-5 materials synthesized in the presence of water (i.e., about 7.5%). 相似文献
43.
Berg Cynthia A.; Smith Timothy W.; Ko Kelly J.; Beveridge Ryan M.; Story Paul; Henry Nancy J. M.; Florsheim Paul; Pearce Gale; Uchino Bert N.; Skinner Michelle A.; Glazer Kelly 《Canadian Metallurgical Quarterly》2007,22(4):718
Reports an error in "Task control and cognitive abilities of self and spouse in collaboration in middle-aged and older couples" by Cynthia A. Berg, Timothy W. Smith, Kelly J. Ko, Nancy J. M. Henry, Paul Florsheim, Gale Pearce, Bert N. Uchino, Michelle A. Skinner, Ryan M. Beveridge, Nathan Story and Kelly Glazer (Psychology and Aging, 2007[Sep], Vol 22[3], 420-427). Due to an editing mistake, the order of authorship was incorrect. The correct order is as follows: Berg, Smith, Ko, Beveridge, Story, Henry, Florsheim, Pearce, Uchino, Skinner, & Glazer. (The following abstract of the original article appeared in record 2007-13103-002.) Collaborative problem solving may be used by older couples to optimize cognitive functioning, with some suggestion that older couples exhibit greater collaborative expertise. The study explored age differences in 2 aspects of collaborative expertise: spouses' knowledge of their own and their spouse's cognitive abilities and the ability to fit task control to these cognitive abilities. The participants were 300 middle-aged and older couples who completed a hypothetical errand task. The interactions were coded for control asserted by husbands and wives. Fluid intelligence was assessed, and spouses rated their own and their spouse's cognitive abilities. The results revealed no age differences in couple expertise, either in the ability to predict their own and their spouse's cognitive abilities or in the ability to fit task control to abilities. However, gender differences were found. Women fit task control to their own and their spouse's cognitive abilities; men only fit task control to their spouse's cognitive abilities. For women only, the fit between control and abilities was associated with better performance. The results indicate no age differences in couple expertise but point to gender as a factor in optimal collaboration. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Levin R. V. Nevedomskii V. N. Pushnyi B. V. Bert N. A. Mizerov M. N. 《Technical Physics Letters》2016,42(1):96-98
The possibility of fabricating InAs/GaSb strained-layer superlattices by metalorganic chemical vapor deposition has been experimentally demonstrated. The results of transmission electron microscopy and photoluminescence spectroscopy investigations showed that the obtained structures comprise an InAs?GaSb superlattice on a GaSb substrate consisting of 2-nm-thick InAs and 3.3-nm-thick GaSb layers.
相似文献45.
46.
Pradip Mainali Gauthier Lafruit Qiong Yang Bert Geelen Luc Van Gool Rudy Lauwereins 《International Journal of Computer Vision》2013,104(2):172-197
We present a new method to extract scale-invariant features from an image by using a Cosine Modulated Gaussian (CM-Gaussian) filter. Its balanced scale-space atom with minimal spread in scale and space leads to an outstanding scale-invariant feature detection quality, albeit at reduced planar rotational invariance. Both sharp and distributed features like corners and blobs are reliably detected, irrespective of various image artifacts and camera parameter variations, except for planar rotation. The CM-Gaussian filters are approximated with the sum of exponentials as a single, fixed-length filter and equal approximation error over all scales, providing constant-time, low-cost image filtering implementations. The approximation error of the corresponding digital signal processing is below the noise threshold. It is scalable with the filter order, providing many quality-complexity trade-off working points. We validate the efficiency of the proposed feature detection algorithm on image registration applications over a wide range of testbench conditions. 相似文献
47.
We analyze the class of surfaces which are equipped with rational support functions. Any rational support function can be decomposed into a symmetric (even) and an antisymmetric (odd) part. We analyze certain geometric properties of surfaces with odd and even rational support functions. In particular it is shown that odd rational support functions correspond to those rational surfaces which can be equipped with a linear field of normal vectors, which were discussed by Sampoli et al. (Sampoli, M.L., Peternell, M., Jüttler, B., 2006. Rational surfaces with linear normals and their convolutions with rational surfaces. Comput. Aided Geom. Design 23, 179–192). As shown recently, this class of surfaces includes non-developable quadratic triangular Bézier surface patches (Lávička, M., Bastl, B., 2007. Rational hypersurfaces with rational convolutions. Comput. Aided Geom. Design 24, 410–426; Peternell, M., Odehnal, B., 2008. Convolution surfaces of quadratic triangular Bézier surfaces. Comput. Aided Geom. Design 25, 116–129). 相似文献
48.
Careful combination of a metal compound,a ligand and an inorganic support material leads to supramolecular catalysts that mimic the structural, organizational and functional aspects of enzyme activity.After discussing essential features of metalloenzyme-catalyzed reactions and coordination chemistry in inorganic hosts, we present examples of supramolecular materials selected from our own work that eventually resulted in useful catalysts for organic transformations in the liquid phase. 相似文献
49.
Graphene sheets can be regarded as base structure of many carbon nanostructures, and atomic arrangements and variations in the atomic structure have a drastic impact on their unique properties. Using a single/double layer graphene model structure, we present a strategy to “see” single carbon atoms in 3-D. In high-resolution transmission electron microscopy, exit-wave images are essential to obtain and to understand 3-D atomic structure. Using electrons at 80 kV not only minimizes the knock-on damage, but also improves the detection sensitivity due to the higher scattering power of carbon at lower acceleration voltage of the electron. Using experiments and image simulations, positions of individual carbon atoms in a single/double layer structure in graphene have been identified. 相似文献
50.