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991.
Ackerman Mark S. Dong Tao Gifford Scott Kim Jungwoo Newman Mark W. Prakash Atul Qidwai Sarah Garcí a David Villegas Paulo Cadenas Alejandro S nchez-Esguevillas Antonio Aguiar Javier Carro Bel n Mailander Sean Schroeter Ronald Foth Marcus Bhattacharya Amiya Dasgupta Partha 《Pervasive Computing, IEEE》2009,8(4):28-32
This issue includes four works in process on issues and applications in location-aware computing: letting users set and control privacy policies when they use location-aware applications, cold-starting recommender systems for mobile location-aware services, aggregating contextual information for location-based applications, and applying location-based services to public transportation environments. The department also includes a report on lightweight virtualization of low-power wireless personal area networks. 相似文献
992.
Multimedia Tools and Applications - This paper describes a robust and accurate technique for iris center localization by combining supervised regression based approach and image gradients. The... 相似文献
993.
This study addresses the problem of determining the most reliable time-adaptive strategy on a stochastic and time-dependent transportation network. The reliability is measured as a conic combination of the mean and standard-deviation of travel time and is termed robust-cost. The stochastic time-dependent network is represented as a directed acyclic hypergraph, where the time-adaptive strategies correspond to the hyperpaths. This representation transforms the problem to that of determining the hyperpath with the least robust-cost on the constructed hypergraph. The minimum robust-cost strategy problem is difficult to solve because of the non-linear objective function. Consequently, the solution procedures commonly adopted in the literature —that are based on substrategy optimality and substrategy non-dominance —are not applicable to this problem. In this light, we propose a novel bounds-based iterative algorithm that determines the minimum robust-cost strategy on the stochastic and time-dependent networks. This algorithm needs to determine the least and K-best strategies in the second moment of travel time, for which an efficient procedure is also proposed. The algorithm is shown to be exact and exhibit parameterically polynomial behavior; computational tests were performed to demonstrate its efficiency. Further, tests showed that the minimum robust-cost strategy compromises little in terms of the mean travel time (0.2%–2.9%) —compared to least expected travel time strategy— with significant reduction in travel time variability (6.2%–29.8%). 相似文献
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A new finite-dosing cell for in vitro skin permeation studies was recently developed to overcome the deficiencies observed in the commercially available Franz diffusion cell and to accomplish the solution hydrodynamics and temperature control required in studying the rate profiles of skin permeation.
Results of comparative studies indicated that the improved diffusion cell, named Keshary-Chien diffusion cell, can achieve and maintain the target body temperature on the skin surface and in the receptor solution, which cannot be accomplished by the Franz diffusion cell. Solution mixing efficiency was substantially improved, so the drug distribution and concentration homogeneity could be achieved in the Keshary-Chien diffusion cell within a duration four times shorter than in the Franz diffusion cell; and a 3-fold reduction in the thickness of the hydrodynamic boundary layer was achieved, so the effect of mass transfer in the hydrodynamic boundary layer on the skin permeation rate profiles was minimized. 相似文献
Results of comparative studies indicated that the improved diffusion cell, named Keshary-Chien diffusion cell, can achieve and maintain the target body temperature on the skin surface and in the receptor solution, which cannot be accomplished by the Franz diffusion cell. Solution mixing efficiency was substantially improved, so the drug distribution and concentration homogeneity could be achieved in the Keshary-Chien diffusion cell within a duration four times shorter than in the Franz diffusion cell; and a 3-fold reduction in the thickness of the hydrodynamic boundary layer was achieved, so the effect of mass transfer in the hydrodynamic boundary layer on the skin permeation rate profiles was minimized. 相似文献
996.
Ping Yan Patrice Batamack G. K. Surya Prakash George A. Olah 《Catalysis Letters》2005,101(3-4):141-143
Gallium triflate catalyzed dehydration of aldoximes to nitriles is described in good to excellent yields. Good catalytic and dehydrating capabilities of gallium triflate are demonstrated through this dehydration reaction. 相似文献
997.
Balsalazide is a prodrug of mesalazine which has an inert carrier molecule instead of the sulfapyridine moiety of sulfasalazine. Balsalazide 6.75 g/day was more effective than mesalazine 2.4 g/day in at least 1 trial and as effective as sulfasalazine 3 g/day for inducing remission in patients with acute ulcerative colitis in 8- and 12-week trials. Moreover, complete symptom relief occurred more promptly with balsalizide 6.75 g/day than with mesalazine 2.4g/day. In long term studies, balsalazide 2 g/day was as effective as sulfasalazine 2 g/day and balsalazide 6 g/day was as effective as mesalazine 1.5 g/day, in maintaining remission in patients with ulcerative colitis. The tolerability profile of balsalazide is significantly better than that of sulfasalazine; 70% of sulfasalazine-intolerant patients were able to tolerate balsalazide. 相似文献
998.
Tricyclic antidepressants (TCAs) have been used successfully in the treatment of irritable bowel syndrome and unexplained chest pain. Little information is available regarding their use in other functional gastrointestinal disorders. Clinical charts were analyzed from 37 outpatients (mean age 45 +/- 2 years, 25 females/12 males) with chronic nausea and vomiting that could not be explained by any conventional organic disorder (mean duration of symptoms 28 +/- 8 months). Twenty-one (57%) had chronic persistent symptoms; 16 (43%) had intermittent relapsing symptoms; 13 (35%) also had pain as a dominant complaint. Each patient had been treated with TCAs specifically for the gastrointestinal symptoms (amitriptyline, desipramine, nortriptyline, doxepin, or imipramine), and the subject group was followed for 5.4 +/- 1.1 months. Response (at least moderate symptom reduction using a priori chart rating criteria) occurred in 31 patients (84%), and complete symptom remission occurred in 19 (51%)--in 41% with the first TCA trial. Dose at response averaged 50 mg/day, and outcome was unrelated to TCA used. Logistic regression analysis revealed that pain dominance interfered with remission (P = 0.03), but other clinical characteristics were not predictive of outcome. This uncontrolled clinical experience indicates that the open-label response rate of functional nausea and vomiting to low dosages of TCAs resembles that noted in irritable bowel syndrome. TCAs should be studied in controlled fashion for this and related dyspeptic syndromes, as the success of other treatments is limited. 相似文献
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1000.