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201.
E. J. O'Brien, M. L. Rizzella, J. E. Albrecht, and J. G. Halleran (1998) demonstrated that, consistent with the memory-based text processing view, outdated or incorrect information can be reactivated through a passive resonance process. Once reactivated, this outdated information can still influence comprehension. R. A. Zwaan and C. J. Madden (2004) suggested that the O'Brien et al. findings resulted from problems with the materials used. The present authors show that the possible "problems" identified by Zwaan and Madden do not adequately explain the findings of O'Brien et al. and that Zwaan and Madden's Experiment 3 lacks sufficient control or power to support their alternative interpretation of O'Brien et al. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
202.
Errors in the refractive and absorptive indices derived from reflectance measurements on relatively low-absorbing organic substances in two media are discussed, with particular reference to coal macerals and cokes. Variation of errors in refractive and absorptive indices at different levels of reflectance, and the effect of different combinations of sign and magnitude of reflectance error on the two parameters, are presented in both tabulated form and as diagrams. The errors in the refractive and absorptive indices vary in relation to reflectance level, the reflectance difference between standard and unknown, the difference between the refractive indices of the unknown and the immersion oil and the wavelength of reflectance measurement within the visible spectrum. Despite the variation, it is possible to obtain useful values for the parameters within the low-absorbing range. If the absorption is negligible, it may not be possible to obtain realistic values for absorptive index, but even where this is the case, satisfactory values for refractive index can still be obtained. Suggestions are made on how to minimize reflectance errors and to increase the accuracy of dispersion curves for derived refractive and absorptive indices within the visible spectrum.  相似文献   
203.
A custom, low-cost force measurement system for manufacturing is presented that exploits robotic link deflection for measurement purposes instead of utilizing a commercially purchased load cell. Force measurement can be an important aspect to many manufacturing processes, as it can allow for force feedback control or other process-planning related operations, such as tool-workpiece autozero or through-the-tool joint tracking. This system is demonstrated on a machine that is used for Friction Stir Welding research, and a Finite Element Analysis is also conducted on the robotic link that is used for axial force measurement purposes. This system may be particularly attractive to small businesses or low-volume manufacturers whose smaller operating budgets may normally prohibit them from implementing force measurement systems.  相似文献   
204.
The potential for community-led local sustainability initiatives to play a key role in a transition towards a low-carbon economy has been acknowledged by both policymakers and researchers. To date, such initiatives have predominantly been established through the efforts of volunteers, resulting in a scattered uptake across towns, cities and other communities in the UK and further afield. In a context where local and national Government are increasingly seeking to deliver local action on climate change in partnership with community organisations, is it possible or desirable for Government and other publicly funded bodies to successfully set up these grassroots initiatives “from the outside” where none exist already? This paper describes a project which explored this question through the provision of a 2-year programme of support for local action on climate change in a sub-region of the UK. Community development strategies were employed with a view to establishing new grassroots climate change initiatives in a range of different communities. The results indicate some potential for the strategy to meet with success, with several new groups and small-scale projects being established as a result. However, the short lifespan of many of the organisations set up and the relatively low impact on carbon emission reduction of their activities raises questions about the effectiveness of grassroots initiatives and how support of their activities can be delivered most effectively to maximise impact and improve cost effectiveness.  相似文献   
205.
206.
The use of self‐assembling, pre‐polymer materials in 3D printing is rare, due to difficulties of facilitating printing with low molecular weight species and preserving their reactivity and/or functions on the macroscale. Akin to 3D printing of small molecules, examples of extrusion‐based printing of pre‐polymer thermosets are uncommon, arising from their limited rheological tuneability and slow reactions kinetics. The direct ink write (DIW) 3D printing of a two‐part resin, Epon 828 and Jeffamine D230, using a self‐assembly approach is reported. Through the addition of self‐assembling, ureidopyrimidinone‐modified Jeffamine D230 and nanoclay filler, suitable viscoelastic properties are obtained, enabling 3D printing of the epoxy–amine pre‐polymer resin. A significant increase in viscosity is observed, with an infinite shear rate viscosity of approximately two orders of magnitude higher than control resins, in addition to, an increase in yield strength and thixotropic behavior. Printing of simple geometries is demonstrated with parts showing excellent interlayer adhesion, unachievable using control resins.  相似文献   
207.
In the United Kingdom, blanket antibiotic dry cow therapy (BDCT) is commonly prescribed. An alternate strategy is selective dry cow therapy (SDCT) whereby a teat sealant is given instead of an antibiotic to cows with a low probability of infection. Switching from BDCT to SDCT can significantly reduce antibiotic use. The aims of this study were to explore how veterinarians (vets) rationalized their prescribing decisions for mammary treatments at drying off, and the barriers and motivators they perceived to implementing SDCT. Face-to-face interviews were conducted with 20 purposively recruited vets from 6 practices in England, United Kingdom. The data were analyzed qualitatively using an inductive thematic analysis. The majority of participants stated a personal preference for SDCT because it constitutes more responsible antibiotic use. On the majority of farms, the prescribing decision was taken by a senior veterinarian and BDCT was prescribed. Less experienced vets expressed a desire to be more involved in the decision-making process. The first theme, prioritizing responsible antimicrobial prescribing, encapsulated the difficulties vets expressed engaging with farmers, conflicts of interest, and vets’ determination to take action. The second theme, the effect of a vet's experience on their ability to influence farmers, focused on the specific challenges faced by less experienced vets and the importance of vets being both trusted by farmers and being knowledgeable. The third theme, vets’ perceptions about the risk and complexity of implementing SDCT, revealed markedly different levels of concern and fears about adverse outcomes with teat sealants versus antibiotics. The results also showed differences in perceptions about how difficult SDCT is to implement in practice. The last theme, vets’ suggestions for facilitating the introduction of SDCT, was wide ranging and provided useful insight from a veterinary perspective into ways to facilitate SDCT. Initiatives that seek to alter vets’ perceptions of the risks associated with switching to using SDCT are likely to prove useful in facilitating change. Our results also suggest that it is vital for senior vets to take a leading role in facilitating farms to implement SDCT. Less experienced colleagues may benefit from more help from senior vets to gain the trust of farmers and to become involved more quickly in herd-level preventive medicine. Vets must work together and take a united approach to reduce antimicrobial use.  相似文献   
208.
The strengths of four brittle materials―cordierite glass ceramic, fused silica, silicon, and polycrystalline alumina were measured after exposure to weakly corrosive water and moderately corrosive buffered HF (BHF) solution. Exposure to water did not alter the strengths in subsequent inert strength tests and decreased the strengths in reactive strength tests. Exposure to BHF increased the strengths in both tests, but only after an incubation exposure time. Prior to the incubation time, the BHF had the same effect as water, suggesting that the bond rupture kinetics were unaffected. Examination of strength‐controlling indentation flaws after the incubation time showed clear corrosive effects on the flaw geometry indicative of reductions in the indentation residual stress fields. The implication is that moderately corrosive environments increase the strength or lifetime of a brittle component by reducing the crack driving force via flaw alteration and do not, as perhaps expected, decrease the strength or lifetime through enhanced chemical reactivity.  相似文献   
209.
We describe a reduction from temporal property verification to a program analysis problem. First we present a proof system that, unlike the standard formulation, is more amenable to reasoning about infinite-state systems: disjunction is treated by partitioning, rather than enumerating, the state space and temporal operators are characterized with special sets of states called frontiers. We then describe a transformation that, with the use of procedures and nondeterminism, enables off-the-shelf program analysis tools to naturally perform the reasoning necessary for proving temporal properties (e.g. backtracking, eventuality checking, tree counterexamples for branching-time properties, abstraction refinement, etc.). Using examples drawn from the PostgreSQL database server, Apache web server, and Windows OS kernel, we demonstrate the practical viability of our work.  相似文献   
210.
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