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991.
Affect, generalization, and the perception of risk. 总被引:1,自引:0,他引:1
Investigated the role of affect in judgments of risk in 4 experiments. 557 Ss were recruited on college campuses and read paragraphs modeled after newspaper reports that described fatal or nonfatal accidents or (Exp III) positive events. Ss were later asked to estimate the chances of specific fatal or nonfatal accidents happening to them and/or to the population in general. Experimental manipulations of affect induced by report of a tragic event produced a pervasive increase in Ss' estimates of the frequency of many risks and other undesirable events. Contrary to expectation, the effect was independent of the similarity between the report and the estimated risk: An account of a fatal stabbing did not increase the frequency estimate of homicide more than the estimates of unrelated risks such as natural hazards. An account of a happy event that created positive affect produced a comparable global decrease in judged frequency of risks. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Eric Sheppard 《Papers in Regional Science》1983,52(1):175-186
Two sources of urban growth differentials that intimately stem from the interdependencies between cities are unequal gains from interurban commodity trade, and spatial differentials in corporate ownership. Each of these phenomena has the potential of redistributing the physical and monetary surplus accruing from production unevenly between cities. This study develops a theoretical model to examine these problems, taking as its starting point a Marxian model of reproduction, prices, profits and wages. An interurban model of production and trade for a capitalist society with production restricted to small enterprises is constructed. Some system-wide and local accounting relationships are formulated that reveal the flows of profits, investment income, and surplus value between cities as a result of the postulated trading patterns. These are used to demonstrate the difference between profit and surplus value movements among locations, and to mathematically formulate the classical problem of unequal exchange of labour values relative to monetary values. 相似文献
993.
Gate-level logic simulation takes up more CPU time as system complexity increases. A special-purpose system which can cut verification time by several orders of magnitude is described. The Yorktown Simulation Engine (YSE) is a highly parallel programmable machine which can simulate up to 1 M gates at a speed of over 2000M gate simulations per second. It is estimated that the IBM 3081 processor could have been simulated at over 1 000 instructions per second on YSE. Gate-level logic simulation is reviewed and the architecture and hardware implementation of the YSE is described. The software architecture, including compiler, linker and register-level language translator, Ysetran, architecture, are detailed. 相似文献
994.
995.
Soap manufacture from fatty acids is a well established precess with some advantages over continuous saponification of neutral fats. These include:
- Ability to use cheaper fats.
- Easier glycerol recovery.
- Better control over by-products.
- Versatility-fatty acids can be used to make other derivatives than soaps.
996.
997.
Effect of electrolyte concentration on the viscosity and voltammetry of supercritical solutions 总被引:1,自引:0,他引:1
The viscosity of a supercritical electrolyte solution is measured for the first time using a modified quartz crystal microbalance, and it is shown that ionic solvation leads to a significant structuring of the solvent and an appreciable increase in solution viscosity. Voltammetric investigations in the electrolyte solutions are used to confirm the magnitude of the viscosity changes, and these account for the appreciably lower than expected peak currents. 相似文献
998.
A uniform-field design approach can improve the performance of microanalytical, chip-based devices for a number of applications, including separations and sample preparation. The faceted prism paradigm allows the design of microfluidic devices possessing spatially uniform fields in electrokinetically driven flows. We present the first quantitative study of the velocity fields obtained using faceted interfaces between deep and shallow channel sections. Electrokinetic flows were generated in a series of wet-etch fabricated microfluidic channels. The resulting velocity fields were analyzed by particle image velocimetry and compared with simulations of the two-dimensional Laplace equation using both the designed channel geometry and the as-fabricated channel geometry. This analysis found localized differences between the designed and observed flow fields that were directly attributable to the limitations of isotropic substrate etching. Simulations using the as-fabricated channel geometry reproduced the experimental electrokinetic velocity field, quantitatively accounting for speed field variations due to the limits of the fabrication method. The electrokinetic speed fields were also compared to corresponding pressure-driven speed fields. 相似文献
999.
Distributed Monitoring of Concurrent and Asynchronous Systems* 总被引:1,自引:0,他引:1
Eric?Fabre Albert?BenvenisteEmail author Stefan?Haar Claude?Jard 《Discrete Event Dynamic Systems》2005,15(1):33-84
In this paper we study the diagnosis of distributed asynchronous systems with concurrency. Diagnosis is performed by a peer-to-peer distributed architecture of supervisors. Our approach relies on Petri net unfoldings and event structures, as means to manipulate trajectories of systems with concurrency. This article is an extended version of the paper with same title, which appeared as a plenary address in the Proceedings of CONCUR2003.*This work was supported by the RNRT project MAGDA2, funded by the Ministère de la Recherche; other partners of the project are France Telecom R&D, Alcatel, Ilog, and Paris- Nord University. 相似文献
1000.
Stutts J Feaganes J Reinfurt D Rodgman E Hamlett C Gish K Staplin L 《Accident; analysis and prevention》2005,37(6):602-1101
Unobtrusive video camera units were installed in the vehicles of 70 volunteer drivers over 1-week time periods to study drivers’ exposure to distractions. The video data were coded based on a detailed taxonomy of driver distractions along with important contextual variables and driving performance measures. Results show distractions to be a common component of everyday driving. In terms of overall event durations, the most common distractions were eating and drinking (including preparations to eat or drink), distractions inside the vehicle (reaching or looking for an object, manipulating vehicle controls, etc.), and distractions outside the vehicle (often unidentified). Distractions were frequently associated with decreased driving performance, as measured by higher levels of no hands on the steering wheel, eyes directed inside rather than outside the vehicle, and lane wanderings or encroachments. Naturalistic driving studies can provide a useful supplement to more controlled laboratory and field studies to further our understanding of the effects of all types of distractions on driving safety. 相似文献