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261.
J.M. Veenstra A.M. Duncan C.N. Cryne B.R. Deschambault J.I. Boye M. Benali M. Marcotte S.M. Tosh E.R. Farnworth A.J. Wright 《Food research international (Ottawa, Ont.)》2010,43(2):553-559
Despite their demonstrated health benefits, consumption of pulses in Western societies has traditionally been low. This is, in part, due to the perception that pulses cause flatulence and gastrointestinal upset. This randomized, double-blind placebo-controlled, cross-over study assessed the impact of 28 consecutive days consumption of 100 g dry weight Kabuli chickpeas, green Laird lentils, and green peas, in comparison to a potato control, on perceived flatulence, abdominal comfort, bowel movements and overall gastrointestinal function using a questionnaire with yes/no and visual analog rankings, in 21 healthy males between the ages of 19–40. Questionnaires were completed during three phases (PRE, EARLY, LATE) of each treatment period. Chi-square (occurrence) and Wilcoxon test (severity rank) analyses revealed minor changes in occurrence and/or severity of flatulence and abdominal comfort, but no changes in overall gastrointestinal function. These results demonstrate that pulses containing oligosaccharides are well tolerated with negligible perceived changes in flatulence and overall gastrointestinal function when incorporated into the diet of healthy adult males. 相似文献
262.
W. Guo J. D. Wright S. B. Cahn J. A. Nikkel D. N. McKinsey 《Journal of Low Temperature Physics》2010,158(1-2):346-352
We demonstrate that metastable helium molecules can be used as tracers to visualize the flow of the normal fluid in superfluid 4He using a laser-induced-fluorescence technique. The flow pattern of a normal-fluid jet impinging on the center of a copper disc is imaged. A ring-shaped circulation structure of the normal fluid is observed as the jet passes across the disc surface. The fluorescence signal for the molecules trapped in the circulation structure is measured as a function of time after we turn off the molecule source. The radiative lifetime and density of the molecules can be determined by fitting the measured data using a simple analytic model. We also discuss a proposed experiment on using a previously developed molecule tagging-imaging technique to visualize the normal-fluid velocity profile during the transition of quantum turbulence in a thermal counterflow channel. 相似文献
263.
An efficient video-on-demand model 总被引:1,自引:0,他引:1
An efficient video-on-demand system uses a practical, technologically sophisticated model to serve the viewing needs of a wide audience, including meeting the peak demand for popular, newly released films 相似文献
264.
It is generally assumed when using Bayesian inference methods for neural networks that the input data contains no noise or corruption. For real-world (errors in variable) problems this is clearly an unsafe assumption. This paper presents a Bayesian neural-network framework which allows for input noise provided that some model of the noise process exists. In the limit where the noise process is small and symmetric it is shown, using the Laplace approximation, that this method gives an additional term to the usual Bayesian error bar which depends on the variance of the input noise process. Further, by treating the true (noiseless) input as a hidden variable and sampling this jointly with the network weights using a Markov chain Monte Carlo method, it is demonstrated that it is possible to infer the regression over the noiseless input. 相似文献
265.
Kenji Takizawa Creighton Moorman Samuel Wright Jason Christopher Tayfun E. Tezduyar 《Computational Mechanics》2010,46(1):31-41
The stabilized space–time fluid–structure interaction (SSTFSI) technique was applied to arterial FSI problems soon after its
development by the Team for Advanced Flow Simulation and Modeling. The SSTFSI technique is based on the Deforming-Spatial-Domain/Stabilized
Space–Time (DSD/SST) formulation and is supplemented with a number of special techniques developed for arterial FSI. The special
techniques developed in the recent past include a recipe for pre-FSI computations that improve the convergence of the FSI
computations, using an estimated zero-pressure arterial geometry, Sequentially Coupled Arterial FSI technique, using layers
of refined fluid mechanics mesh near the arterial walls, and a special mapping technique for specifying the velocity profile
at inflow boundaries with non-circular shape. In this paper we introduce some additional special techniques, related to the
projection of fluid–structure interface stresses, calculation of the wall shear stress (WSS), and calculation of the oscillatory
shear index. In the test computations reported here, we focus on WSS calculations in FSI modeling of a patient-specific middle
cerebral artery segment with aneurysm. Two different structural mechanics meshes and three different fluid mechanics meshes
are tested to investigate the influence of mesh refinement on the WSS calculations. 相似文献
266.
Philip M. Delaforce Julie A. Yeomans Neil C. Filkin Gary J. Wright Rachel C. Thomson 《Journal of the American Ceramic Society》2007,90(3):918-924
Nickel oxide (NiO) was screen printed onto the surfaces of 3 and 8 mol% yttria-stabilized zirconia (YSZ) dense pre-fired substrates and then heat treated at temperatures from 1350° to 1550°C. The effect of NiO was dependent on the yttria content of the substrate. In 3 mol% YSZ, it was found to alter the phase composition from predominantly tetragonal with a small amount of cubic phase to one consisting of approximately equal amounts of cubic and monoclinic phase. The cubic grains were much larger than the monoclinic ones and contained more nickel. Furthermore, nickel was observed to migrate through the thickness of the tile, a distance of approximately 200 μm. In the 8 mol% YSZ substrates, the phase composition was unaltered, although large grains developed under the printed NiO layer and the nickel migration was confined to the extent of these large grains. 相似文献
267.
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269.
A review of several publications of the Oak Ridge National Laboratory's Biofuels Feedstock Development Program and final reports from the herbaceous crop screening trials show that technology, environmental, and funding issues influenced the decision to focus on a single herbaceous “model” crop species. Screening trials funded by the U.S. Department of Energy in the late 1980s to early 1990s assessed thirty-four herbaceous species on a wide range of soil types at thirty-one different sites spread over seven states in crop producing regions of the U.S. Several species, including sorghums, reed canarygrass, wheatgrasses, and other crops, were identified as having merit for further development. Six of the seven institutions performing the screening included switchgrass among the species recommended for further development in their region and all recommended that perennial grasses be given high research priority. Reasons for the selection of switchgrass included demonstration of relatively high, reliable productivity across a wide geographical range, suitability for marginal quality land, low water and nutrient requirements, and other positive environmental attributes. Crop screening results, economic and environmental assessments by the Biofuels Feedstock Development Program staff, and Department of Energy funding limitations all contributed to the decision to further develop only switchgrass as a “model” or “prototype” species in 1991. The following ten year focus on development of switchgrass as a bioenergy crop proved the value of focusing on a single “model” herbaceous crop. The advancements and attention gained were sufficient to give government leaders, policymakers, farmers, and biofuel industry developers the confidence that lignocellulosic crops could support an economically viable and environmentally sustainable biofuel industry in the U.S. 相似文献
270.
Five model compounds representing part of the structure of polystyrylpy-ridines have been studied using differential scanning calorimetry (DSC) and pyrolysis-gas chromatography-mass spectrometry (P-GC-MS). Cured resin samples have also been examined by pyrolysis-gas chromatography-mass spectrometry and thermogravimetry. DSC showed that, with one exception, all the model compounds were crystalline as supplied and recrystallisation occurred readily on melting and cooling. The breakdown products in P-GC-MS, with the exception of 1-methyleneindene (produced from three of the model compounds), could all be explained on the basis of general bond scission followed by H or C6H5 transfer. Thermogravimetry indicated the minimum cure cycle necessary to give optimum thermal stability on a weight loss basis. 相似文献