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31.
Zitt Michel Ramanana-Rahary Suzy Bassecoulard Elise Laville Françoise 《Scientometrics》2003,57(2):295-320
This article depicts some features of the geography of science and technology outputs in the EU, with a particular attention
to regional “co-location” of these two pillars of the “knowledge-based society”. Economists have, for a decade, paid great
attention to local “spillovers” stating that industrial firms often draw advantages from the presence of nearby academic centres.
The presence in the same areas of strong academic and technological resources is both a condition and a result of science-technology
interactions. Concentrating on publications and patents as proxies of the science and technology level in regions, we built
a typology of regions according to their commitment to the two knowledge-base activities and then analysed the co-locations
of science and technology from several points of view. A fine-grain lattice, mainly based on standard Nuts3 level, was used.
Co-location, at the EU level, is not a general rule. A strong potential for spillover/ interaction does exist in the top-class
regions which concentrate a high proportion of European S and T output. But for regions with a small/medium level of S&T activity,
a divergence of orientations appears between a science-oriented family and a technology-oriented family, indicating an imbalance
between local S and T resources. If we look at the S-oriented regions, whilst controlling for underlying factors, such as
population and regional economic product, a significant geographic linkage between T and S appears. This suggests a trajectory
of science-based technological development. A careful examination of S&T thematic alignments and specialisation is necessary
to develop the hypothesis that fostering academic resources could increase the technological power along a growth path.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
32.
The main purpose of this study is to evaluate the computational efficiency of algorithms for calculating shortest paths when they are correctly coded by using the C programming language. The eight algorithms that we selected for this experiment are the most efficient, either measured in terms of worst-case bounds or marked as such from previous computational studies; they include the redistributive heap algorithm. We suggest computer implementations that use the full power of C. In particular, the network representation and the various data structures used to keep the scan eligible list may be managed by using only additions and no multiplications, while it is not possible with FORTRAN. These capabilities, unique to C, yield several interesting conclusions: one may expect to speed up a shortest path algorithm by a factor of 20%; in some cases, this factor may reach 30%. Interestingly, the level of programming difficulty required to achieve these benefits is not greater than that required by implementations using arrays. 相似文献
33.
Christophe Lombard Stephane Le Doze Eric Marencak Paul-Marie Marquaire David Le Noc Grégory Bertrand François Lapicque 《International Journal of Hydrogen Energy》2006
The paper reports the results of on-site regeneration catalytic bed of the natural gas reformer in a 5 kW PEM fuel cell system. The Ni catalyst previously poisoned by sulphur from the available natural gas, could be re-activated by injection of pure water steam, following the method developed for industrial reformers using the same metal catalyst: this method was shown to be perfectly efficient, provided no natural gas was fed during the operation. Results of the tests conducted are presented and discussed in relation to published data on S-sorption on Ni surfaces. 相似文献
34.
Sabri Boughorbel Jean-Philippe Tarel Fran?ois Fleuret Nozha Boujemaa 《The Journal of supercomputing》1988,2(4):449-450
Contributing authors 相似文献
35.
36.
We propose a method for non-uniform reconstruction of 3D scalar data. Typically, radial basis functions, trigonometric polynomials or shift-invariant functions are used in the functional approximation of 3D data. We adopt a variational approach for the reconstruction and rendering of 3D data. The principle idea is based on data fitting via thin-plate splines. An approximation by B-splines offers more compact support for fast reconstruction. We adopt this method for large datasets by introducing a block-based reconstruction approach. This makes the method practical for large datasets. Our reconstruction will be smooth across blocks. We give reconstruction measurements as error estimations based on different parameter settings and also an insight on the computational effort. We show that the block size used in reconstruction has a negligible effect on the reconstruction error. Finally we show rendering results to emphasize the quality of this 3D reconstruction technique. 相似文献
37.
Organo-functional silanes which were able to form chemical bonds with kaolinite and could also have an affinity to the materials of concern here, were studied by the sol-gel process. Polymethacrylate with trialkoxy silyl functional groups were prepared, hydrolysed and co-condensed with kaolinite. The progress of the hydrolysis, which proceeded very slowly, was followed by Karl-Fischer titration. Thermal behavior was investigated by differential thermal analysis. The extent of the reaction leading to network formation was qualitatively followed by Fourier transform-infrared spectroscopy and X-ray diffraction. Free-radical polymerization was carried out ultrasonically in the presence of a catalyst. Trimethoxy silane end-capped silane was found to be covalently bonded to kaolinite. The copolymers, with various amounts of kaolinite, were then hydrolysed and co-condensed in the presence of a catalyst to yield sol-gel materials which have a controllable combination of properties of both the polymer and kaolinite. 相似文献
38.
The effects of an elevated temperature and a 5 wt% silicon addition on the resultant microstructure and inherent phases of Stellite 6 were investigated by using room and high temperature optical microscopy, X-ray diffraction, scanning electron microscopy (SEM) and also bulk hardness and microhardness measurements. It has been observed that exposing Stellite 6 to heat treatments at 1000°C results in a characteristic textured structure and coarsening of interdendritic regions due to bulk diffusion. In addition, both dendritic and interdendritic hardness values increase due to texture formation and increased amounts of carbide and intermetallic phases, respectively. On the other hand, silicon addition to Stellite 6 causes the transformation of the original spongy dendritic microstructure in as-cast Stellite 6 to a eutectic dendritic and skeleton interdendritic structure. Also, when silicon added Stellite 6 was heat treated at 1000°C, particulates emanating from the interdendritic skeleton become irregularly dispersed in the dendritic region. In addition, similarly to Stellite 6; a high temperature heat treatment results in an increase in hardness values of silicon added Stellite 6 due to the presence of an Co2 Si intermetallic phase. 相似文献
39.
Messing Karen Lefrançois Mélanie Saint-Charles Johanne 《Computer Supported Cooperative Work (CSCW)》2021,30(2):215-249
Computer Supported Cooperative Work (CSCW) - Work activity ergonomics (sometimes called francophone ergonomics) draws heavily on observation in order to support transformation of work to arrive at... 相似文献
40.
Prof. Alessia Carocci Dr. Mariagrazia Roselli Prof. Roberta Budriesi Dr. Matteo Micucci Prof. Jean-François Desaphy Dr. Concetta Altamura Dr. Maria Maddalena Cavalluzzi Dr. Maddalena Toma Dr. Giovanna Ilaria Passeri Dr. Gualtiero Milani Dr. Angelo Lovece Prof. Alessia Catalano Dr. Claudio Bruno Dr. Annalisa De Palma Prof. Filomena Corbo Prof. Carlo Franchini Prof. Solomon Habtemariam Prof. Giovanni Lentini 《ChemMedChem》2021,16(3):578-588
Under the hypothesis that cardioprotective agents might benefit from synergism between antiarrhythmic activity and antioxidant properties, a small series of mexiletine analogues were coupled with the 2,2,5,5-tetramethylpyrroline moiety, known for its antioxidant effect, in order to obtain dual-acting drugs potentially useful in the protection of the heart against post-ischemic reperfusion injury. The pyrroline derivatives reported herein were found to be more potent as antiarrhythmic agents than mexiletine and displayed antioxidant activity. The most interesting tetramethylpyrroline congener, a tert-butyl-substituted analogue, was at least 100 times more active as an antiarrhythmic than mexiletine. 相似文献