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41.
In the previous paper, we reported the stand growth of slash pine (Pinus elliottii) during the first 11.5 years of plantation in response to (1) initial fertilization at plantation establishment with P rates of 11, 22, 45 and 90 kg P ha–1 which were either banded or broadcast in the presence or absence of basal fertilizers containing 50 kg N ha–1, 50 kg K ha–1 and 5 kg Cu ha–1 and (2) application of additional 40 kg P ha–1 at age 10 years. Here we present the responses in foliar nutrient concentrations of slash pine in the first 11.5 years to the initial fertilization and the additional P applied at age 10 years.Foliar N and K concentrations in the first 9.6 years of plantation decreased with the initial P rate. Application of the basal fertilizers improved foliar Cu concentration. Foliar Ca and Mg concentrations increased linearly with the initial P rate. The initial fertilization did not affect foliar Mn concentration in the first 9.6 years. Foliar P concentration increased quadratically with the initial P rate, which accounted for 77–86% of the variation in foliar P concentration. Most of the explained variation in foliar nutrient concentrations was attributable to the plantation age except for foliar P concentration. In the case of foliar P concentration, 53% was explained by the initial P rate, 31% by the plantation age and 2% by the positive interaction between the initial P rate and the plantation age. Foliar P concentration of slash pine at age 11.5 years increased quadratically with the initial P rate and linearly with the additional 40 kg P ha–1 applied at age 10 years, accounting for 81% of the variation in the foliar P concentration. Foliar nutrient analysis indicated that P was the major limiting nutrient affecting the stand growth of slash pine in the first 11.5 years. 相似文献
42.
Kathy A. Northcott Ian Snape Peter J. Scales Geoff W. Stevens 《Chemical engineering science》2005,60(24):6835-6843
Sludge reduction and dewatering is an important aspect of water and waste water treatment. This is especially true in the case of Australia's Antarctic contaminated site remediation program, where the reduction in volume of wastes to be returned to Australia can lead to significant transport and handling cost savings. The dewatering characterisation of water treatment sludges from an Antarctic contaminated site was conducted using a theory of suspension dewatering developed by Buscall, Landman and White. This theory uses fundamental material properties of compressibility and permeability to determine the diffusivity of a suspension. Diffusivity is a useful property that can be used to directly compare the dewaterability of various sludges. In this investigation, several water treatment sludges were collected and characterised in the field to determine the impact of temperature and additives on compressibility, permeability and diffusivity. The Antarctic sludges were found to be less compressible and less permeable than materials such as mineral suspensions and alum water treatment sludges. Compressibility was found to decrease with the addition of powdered coagulation aids such as bentonite and chitosan. 相似文献
43.
Geoff E. Fair Ming Y. He Robert M. McMeeking F. F. Lange 《Journal of the American Ceramic Society》2005,88(7):1879-1885
Finite element modeling and linear elastic fracture mechanics are used to model the residual stresses and failure stress of ceramic composites consisting of polyhedral alumina cores surrounded by thin alumina/mullite layers in residual compression. This type of composite architecture is expected to exhibit isotropic threshold strength behavior, in which the strength of the composite for a particular assumed flaw will be constant and independent of the orientation of tensile loading. The results of the modeling indicate that the strengths of such architectures will be higher than those of laminates of similar architectural dimensions that were previously found to exhibit threshold strength behavior for a particular flaw type. Flexural testing of the polyhedral architectures reveals that failure is dominated by processing defects found at junctions between the polyhedra. Fractography revealed the interaction of these defects with the residual stresses in the compressive layers that separate the polyhedra. 相似文献
44.
It has previously been determined that (13S,9Z,11E)-13-hydroperoxy-9,11-octadecadienoic acid was mainly converted into (13S,9Z,11E)-13-hydroxy-9,11-octadecadienoic acid by 5 N KHO with preservation of the stereochemistry of the reactant [Simpson, T.D.,
and Gardner, H.W. (1993)Lipids 28, 325–330]. In addition, about 20–25% of the reactant was converted into several unknown by-products. In the present work
it was confirmed that the stereochemistry was conserved during the hydroperoxy-diene to hydroxydiene transformation, but also,
novel by-products were identified. It was found that after only 40 min reaction (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid accumulated to as much as 7% of the total. Later, (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid began to disappear, and several other compounds continued to increase in yield. Two of these
compounds, 2-butyl-3,5-tetradecadienedioic acid and 2-butyl-4-hydroxy-5-tetradecenedioic acid, were shown to originate from
(9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid, and they accumulated up to 2–3% each after 4 to 6 h. Some other lesser products included
11-hydroxy-9,12-heptadecadienoic acid, 3-hydroxy-4-tridecenedioic acid, 13-oxo-9,11-octadecadienoic acid and 12,13-epoxy-11-hydroxy-9-octadecenoic
acid. Except for the latter two, most or all of the compounds could have originated from Favorskii rearrangement of the early
product, (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid, through a cyclopropanone intermediate. 相似文献
45.
Although experiments in rodents and human population-based studies have demonstrated the efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) such as sulindac in colorectal cancer (CRC) prevention, a detailed knowledge of the underlying mechanism of action of this drug is limited. To better understand the chemopreventitive effects of sulindac, especially early sulindac-induced apoptotic events, we used the CRC cell line LIM1215 as an experimental model, focusing on proteins secreted into the LIM1215 culture medium - i.e., the secretome. This subproteome comprises both soluble-secreted proteins and exosomes (30-100?nm diameter membrane vesicles released by several cell types). Selected secretome proteins whose expression levels were dysregulated by 1?mM sulindac treatment over 16?h were analyzed using 2-D DIGE, cytokine array, Western blotting, and MS. Overall, 150 secreted proteins were identified, many of which are implicated in molecular and cellular functions such as cell proliferation, differentiation, adhesion, invasion, angiogenesis, metastasis, and apoptosis. Our secretome-based proteomic studies have identified several secreted modulators of sulindac-induced apoptosis action (e.g., Mac-2 binding protein, Alix, 14-3-3 isoforms, profilin-1, calumenin/Cab45 precursors, and the angiogenic/tumor growth factors interleukin 8 (IL-8) and growth related oncogene (GRO-α)) that are likely to improve our understanding of the chemopreventitive action of this NSAID in CRC. 相似文献
46.
Introduction of a data schema to support a design repository 总被引:1,自引:0,他引:1
47.
Oblate drops of water illuminated perpendicular to their symmetry axis exhibit catastrophe patterns near the primary-rainbow scattering angle. Previous patterns include the hyperbolic umbilic focal section and separate lips events [see, e.g., H. J. Simpson and P. L. Marston, Appl. Opt. 30, 3468 (1991)]. The present observations concern a much higher-order singularity analyzed by J. F. Nye [Proc. R. Soc. London Ser. A 438, 397 (1992)], the E(6) or symbolic umbilic, in the scattering by levitated drops with monochromatic and collimated white-light illumination. Photographs show the colors produced when the drop is illuminated by white light. The E(6) occurs when the Gaussian curvature of the scattered wave front vanishes in both principal directions, resulting in a high degree of directional focusing. This type of focusing, although only slightly explored, is applicable to the more general problem of scattering from penetrable spheroids. 相似文献
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Privacy‐preserving targeted mobile advertising: requirements,design and a prototype implementation
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With the continued proliferation of mobile devices, the collection of information associated with such devices and their users—such as location, installed applications and cookies associated with built‐in browsers—has become increasingly straightforward. By analysing such information, organisations are often able to deliver more relevant and better focused advertisements. Of course, such targeted mobile advertising gives rise to a number of concerns, with privacy‐related concerns being prominent. In this paper, we discuss the necessary balance that needs to be struck between privacy and utility in this emerging area and propose privacy‐preserving targeted mobile advertising as a solution that tries to achieve that balance. Our aim is to develop a solution that can be deployed by users but is also palatable to businesses that operate in this space. This paper focuses on the requirements and design of privacy‐preserving targeted mobile advertising and also describes an initial prototype. We also discuss how more detailed technical aspects and a complete evaluation will underpin our future work in this area. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献