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991.
K M Cooper L Ribeiro P Alves V Vozikis S Tsitsamis G Alfredsson T L?vgren M Tuomola H Takalo A Iitia S S Sterk M Blokland D G Kennedy 《Food Additives & Contaminants》2003,20(9):804-812
Many zeranol immunoassay test kits cross-react with toxins formed by naturally occurring Fusarium spp. fungi, leading to false-positive screening results. This paper describes the evaluation and application of recently published, dry reagent time-resolved fluoroimmunoassays (TR-FIA) for zeranol and the toxin alpha-zearalenol. A ring test of bovine urine fortified with zeranol and/or alpha-zearalenol in four European Union National Reference Laboratories demonstrated that the TR-FIA tests were accurate and robust. The alpha-zearalenol TR-FIA satisfactorily quantified alpha-zearalenol in urine fortified at 10-30 ng ml(-1). The specificity-enhanced zeranol TR-FIA accurately quantified zeranol in the range 2-5 ng ml(-1) and gave no false-positive results in blank urine, even in the presence of 30 ng ml(-1) alpha-zearalenol. Zeranol TR-FIA specificity was demonstrated further by analysing incurred zeranol-free urine samples containing natural Fusarium spp. toxins. The TR-FIA yielded no false-positive results in the presence of up to 22 ng ml(-1) toxins. The performance of four commercially available zeranol immunoassay test kits was more variable. Three kits produced many false-positive results. One kit produced only one potential false-positive using a protocol that was longer than that of the TR-FIA. These TR-FIAs will be valuable tools to develop inspection criteria to distinguish illegal zeranol abuse from contamination arising from in vivo metabolism of Fusarium spp. toxins. 相似文献
992.
993.
994.
Thin-film nickel coatings on fiber materials 总被引:1,自引:0,他引:1
L. M. Lyn’kov V. A. Bogush E. A. Senkovets S. M. Zavadskii 《Technical Physics Letters》2003,29(8):641-642
Vacuum deposition of thin films onto fiber materials is a promising method of obtaining electromagnetic screens. We have studied the structure and the electromagnetic properties of machine-knitted fabric coated with nickel by means of magnetron sputtering. When the fabric is irradiated from the metal-coated side, the reflection coefficient is higher by a factor of 1.4 as compared to the case when the same source of electromagnetic radiation is situated on the opposite side (facing the uncoated surface), while the absorption coefficient in both cases is the same. 相似文献
995.
Turning software into a service 总被引:4,自引:0,他引:4
The software as a service model composes services dynamically, as needed, by binding several lower-level services-thus overcoming many limitations that constrain traditional software use, deployment, and evolution. 相似文献
996.
Three kinds of statistical distributions of DC microdischarges in homogeneous electric field are discussed. So far the exponential and streamer distributions have been considered as regular statistics describing microdischarge electron avalanches with low (n~<10/sup 5/) and high (n~>10/sup 8/) average carrier populations, respectively. The distributions of avalanches with intermediate populations n~/spl epsi/(10/sup 5/, 10/sup 8/) that exhibit peculiar convex shapes have not been considered as regular distributions so far. They have been regarded as an experimental artefacts causing deviations from the regular exponential law. On the basis of refined experiments we argue for a new interpretation of those peculiar distribution curves. They have proved to be independent of the remaining two regular statistics and manifest a new distribution law well approximated by the Pareto distribution. The basic physics underlying this separate statistical distribution is intimately related to the inner space charges formed inside the avalanches with higher carrier populations. The inner space charges that modify the local intensity of the electric field and result in redistribution of populations and manifestation of a new statistical behavior. 相似文献
997.
Embedding infrastructure IP to optimize chip-level manufacturing test and debugging has recently become common practice. However, adopting the same approach for boards and systems requires a different family of infrastructure IP. This article introduces such a family and discusses how it can optimize manufacturing test and debugging, as well as support configurability, especially in today's reconfigurable products. 相似文献
998.
A. J. Slifka T. Hall E. S. Boltz 《Journal of research of the National Institute of Standards and Technology》2003,108(2):151-156
A simple measurement system is described for evaluating damage to graphite-epoxy panels, such as those used in high-performance aircraft. The system uses a heating laser and infrared imaging system to measure thermal performance. Thermal conductivity or diffusivity is a sensitive indicator of damage in materials, allowing this thermal measurement to show various degrees of damage in graphite-epoxy composites. Our measurements track well with heat-flux damage to graphite epoxy panels. This measurement system, including analysis software, could easily be used in the field, such as on the deck of an aircraft carrier or at remote air strips. 相似文献
999.
Today, with the increasing popularity of multicore processors, one approach to optimizing the processor's performance is to reduce the execution times of individual applications running on each core by designing and implementing more powerful cores. Another approach, which is the polar opposite of the first, optimizes the processor's performance by running a larger number of applications on a correspondingly larger number of cores, albeit simpler ones. The difference between these two approaches is that the former focuses on reducing the latency of individual applications or threads (it optimizes the processor's single-threaded performance), whereas the latter focuses on reducing the latency of the applications' threads taken as a group (it optimizes the processor's multithreaded performance). The panel, from the 2007 Workshop on Computer Architecture Research Directions, discusses the relevant issues. 相似文献
1000.
The methods of X-ray photoelectron spectroscopy and Auger spectroscopy are used to study surface films formed on zinc and zinc-plated steel in the process of holding in aqueous extracts of mixtures of phosphate and calcium-containing pigments. It is shown that protective films formed mainly of zinc and calcium phosphates of different chemical structure are deposited in inhibited solutions on specimens of pure zinc and zinc-plated steel. The protective properties of these films are much better than the protective properties of the surface layers formed on the metal in the extracts of a single phosphate (or calcium-containing) pigment. The mixture of these pigments may serve as a promising substitution of chromate inhibitors in anticorrosive organic coatings. 相似文献