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121.
122.
Non-linear diffusion (ND) is an iterative difference equation used in several image processing applications such as denoising, segmentation, or compression. The number of iterations required to achieve optimal processing can be very high, making ND not suitable for real-time requirements. In this paper, we study how to reduce complexity of ND so as to achieve minimal number of iterations for real-time image denoising. To do this, we first study the relations between parameters of the iterative equation: the number of iterations, the time step, and the edge strength. We then proceed by estimating the minimally required number of iterations to achieve effective denoising. Then, we relate the edge strength to the number of iterations, to noise, and to the image structure. The resulted minimal iterativity ND is very fast, while still achieves similar or better noise reduction compared to related ND work. This paper also shows how the proposed spatial filter is suitable for structure-sensitive object segmentation and temporal noise reduction. 相似文献
123.
We study finitely generated and finite systems defined by linear partial difference equations with constant coefficients in a Noetherian ring. The two notions coincide for finite rings, and we show that all finite systems exhibit certain periodicity properties. For the particular case of systems over the ring of integers modulo m?>?1, which is important in coding theory, a method is given for determining the number of trajectories, using Gr?bner basis techniques. 相似文献
124.
Eva Hoch Christian Schuh Thomas Hirth Günter E. M. Tovar Kirsten Borchers 《Journal of materials science. Materials in medicine》2012,23(11):2607-2617
Gelatin is a very promising matrix material for in vitro cell culture and tissue engineering, e.g. due to its native RGD content. For the generation of medical soft tissue implants chemical modification of gelatin improves the mechanical properties of gelatin hydrogels and the viscous behavior of gelatin solutions for liquid handling. We present a systematic study on the influence of high degrees of methacrylation on the properties of gelatin solutions and photo-chemically crosslinked hydrogels. Changes from shear thinning to shear thickening behavior of gelatin solutions were observed depending on mass fraction and degree of methacrylation. Degrees of swelling of crosslinked hydrogels ranged from 194 to 770?% and storage moduli G′ from 368 to 5?kPa, comparable to various natural tissues including several types of cartilage. Crosslinked gels proofed to be cytocompatible according to extract testings based on DIN ISO 10933-5 and in contact with porcine chondrocytes. 相似文献
125.
Nam Seung-Hee Kim Young-Min Walsh Marie K. Yim Sun-Hee Eun Jong-Bang 《Food science and biotechnology》2016,25(1):31-39
This study was performed to characterize pear protease proteolytic activity and investigate the use of pear protease as a meat tenderizer. Pear protease was purified and stabilized by 5% dextrin during lyophilization (dry) or concentration (liquid). Pear protease was further characterized with respect to pH, thermodynamics, and enzyme kinetics. Pear protease was stable at a pH range of 5-8 with an optimum pH of 6.5. From Arrhenius plots, liquid protease showed higher temperature dependency (23.49 kJ/mol) than dry protease (18.62 kJ/mol) due to its higher activation energy. The kcat/Km, catalytic efficiency of enzyme, was similar with 2.9 and 2.7 µM/min with dry and liquid proteases. Pear protease was evaluated for its proteolytic activities with casein and beef myofibrillar proteins by individually and combination with fig and kiwifruit proteases. These result indicated that pear and kiwifruit proteases could be complementary to be a desirable product for meat tenderization. 相似文献
126.
A highly nonlinear increase in electrical conductivity and concomitant photoemission occurs not only during “flash sintering” but also in presintered, dense specimens. We report results from experiments with dense specimens that show a strong correspondence between the intensity of photoemission and electrical conductivity of specimens under a variety of conditions of the electrical parameters. It is proposed that both properties are related to the concentration of electron–hole pairs generated in such experiments. 相似文献
127.
John McDonald Rosalee Wolfe Jerry Schnepp Julie Hochgesang Diana Gorman Jamrozik Marie Stumbo Larwan Berke Melissa Bialek Farah Thomas 《Universal Access in the Information Society》2016,15(4):551-566
Generating sentences from a library of signs implemented through a sparse set of key frames derived from the segmental structure of a phonetic model of ASL has the advantage of flexibility and efficiency, but lacks the lifelike detail of motion capture. These difficulties are compounded when faced with real-time generation and display. This paper describes a technique for automatically adding realism without the expense of manually animating the requisite detail. The new technique layers transparently over and modifies the primary motions dictated by the segmental model and does so with very little computational cost, enabling real-time production and display. The paper also discusses avatar optimizations that can lower the rendering overhead in real-time displays. 相似文献
128.
129.
Miloš Skřivan Milan Marounek Michaela Englmaierová Eva Skřivanová 《Food chemistry》2012,130(3):660-664
Information on the combined effect of dietary vitamin C and Se on the composition and oxidative stability of meat of broilers is not available in the literature. In the present experiment, male broiler chickens were fed a maize–wheat–soya diet supplemented with vitamin C at 280 and 560 mg/kg of diet, and Se (sodium selenite or selenised yeast; Se) at 0.3 mg/kg for 5 weeks. After slaughter, samples of thigh meat were analysed. The supplementation of diets with vitamin C or Se increased the protein concentration of the meat at the expense of fat. Vitamin C supplementation increased the vitamin C content of the meat in a dose-dependent manner and decreased the vitamin A concentration in the meat of broilers fed diets with sodium selenite or without a Se supplement. In the meat of the broilers that were fed these diets, the vitamin C decreased the lipid oxidation in meat that was stored for 5 days. No sparing effect of vitamin C was apparent on the amount of vitamin E in the meat. Selenised yeast was more effective in the enrichment of meat with Se than was selenite. Both Se sources increased the activity of glutathione peroxidase and the oxidative stability of the meat. 相似文献
130.
Marie Hurtgen Antoine Debuigne Didier Gigmes Christine Jérôme Christophe Detrembleur 《Polymer》2012,53(20):4353-4358
The grafting mechanism of poly(vinyl acetate) macroradicals prepared by cobalt-mediated radical polymerization onto C60 is investigated. The experimental conditions directly impact the nature and stability of the PVAc/C60 adducts. In the presence of residual initiating radicals that can compete with PVAc° macroradicals for addition onto C60, mixtures of PVAc/C60 adducts having between one and eight polymer chains per C60 are formed. PVAc/C60 adducts prepared with low [PVAc]:[C60] ratios may contain weak C60–C60 bonds that further dissociate and account for the instability of the products. The formation of such dimers can be lessened by increasing the temperature from 30 °C to 100 °C. The temperature increase also allows a complete dissociation of the PVAc-Co dormant species into PVAc° macroradicals and an almost quantitative grafting of eight PVAc chains onto C60, leading to well-defined C60(PVAc)8 octa-adducts. These results might shed new light on the grafting onto C60 of macroradicals prepared by other CRP techniques. 相似文献