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The effects of pear vinegar (PV), which was specially brewed for enhanced galacturonic acid content, on the DSS-induced ulcerative colitis (UC) mouse model were evaluated. PV improved clinical symptoms, colon inflammation, and histological tissue injury in the DSS-induced acute UC mouse model. Moreover, PV suppressed inflammation due to acute UC by suppressing the myeloperoxidase (MPO)-mediated activation of inflammatory cells such as leukocytes and decreasing the serum concentration of IL-6. Our results demonstrated the protective action of PV in the DSS-induced acute UC mouse model. On the other hand, commercial apple vinegar did not show a protective effect in the DSS-induced acute UC mouse model. Our findings indicate that PV may act as a new functional food for inflammatory bowel disease patients.  相似文献   
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Multiply charged ion beam transmission through insulating capillaries is today a very active field of research. Thanks to the work of several groups during the last five years, several features of this unexpected process have been evidenced. The open challenge is to understand and control the self-organized charging-up of the capillary walls, which leads finally to the ion transmission. Up to now, the specific charge distribution on the inner surface, as well as the dynamics of the build-up, are still to be understood. While capillaries usually studied are microscopic pore networks etched in different materials, our concern is in macroscopic single capillaries made of glass. With a length of several centimeters and a diameter of a few micrometers at the exit, these capillaries have nevertheless the same aspect ratio as the etched pores (length/diameter ≈ 100). One of the leading goals of this research on single capillaries is to produce multi-charged ion beams with diameters smaller than a micrometer (nano-beams). These glass capillaries offer the opportunity to be used as an ion funnel due to their amazing properties of guiding and focusing highly charged ion beams without altering neither their initial charge state nor the beam emittance (<10−3 π mm mrad). However, the understanding of the underlying process is not complete and relies on models assuming charge patches distributed along the capillary and which still need to be tested. We present the first observation imaging the dynamics of the charging-up process in single glass capillaries. During the build-up of the self-organized charge deposition on the capillary walls, the 230 keV Xe23+ transmitted beam is deflected back and forth several times as the outgoing current increases. This is in agreement with the picture of charge patches created sequentially along the capillary and thus deflecting the beam until a stationary state is reached.  相似文献   
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The plane thermoelastic problems of a stationary heat source in an infinite plane with an elliptic rigid inclusion and an elliptic hole are analyzed under thermally adiabatic and isothermal boundary conditions. The problems of an elliptic rigid inclusion are derived for the following cases: (1) the case that there are rigid-body displacement and rotation; and (2) the case that there is no rigid-body displacement or rotation. To analyze these problems, the following three fundamental solutions are derived: Problem A, in which a point heat source exists within an infinite domain; Problem B, in which the inclusion has a small amount of rotation; and Problem C, in which the inclusion is subjected to concentrated loads. Two cases can be obtained by superimposing these fundamental solutions. For the hole problem, the fundamental solution (Green's function) is also derived. In analysis, the complex stress functions, the mapping function, and the thermal dislocation method are used. The complex stress functions are obtained as a closed form. For analytic examples, the stress distributions are shown under thermally adiabatic and isothermal boundary conditions. For the crack problem, the stress intensity factors are shown for the location of the heat source.  相似文献   
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Most anti-cancer drug screening assays are currently performed in two dimensions, on flat, rigid surfaces. However, there are increasing indications that three-dimensional (3D) platforms provide a more realistic setting to investigate accurate morphology, growth, and sensitivity of tumor cells to chemical factors. Moreover, interstitial flow plays a pivotal role in tumor growth. Here, we present a microfluidic 3D platform to investigate behaviors of tumor cells in flow conditions with anti-migratory compounds. Our results show that interstitial flow and its direction have significant impact on migration and growth of hepatocellular carcinoma cell lines such as HepG2 and HLE. In particular, HepG2/HLE cells tend to migrate against interstitial flow, and their growth increases in interstitial flow conditions regardless of the flow direction. Furthermore, this migratory activity of HepG2 cells is enhanced when they are co-cultured with human umbilical vein endothelial cells. We also found that migration activity of HepG2 cells attenuates under hypoxic conditions. In addition, the effect of Artemisinin, an anti-migratory compound, on HepG2 cells was quantitatively analyzed. The microfluidic 3D platform described here is useful to investigate more accurately the effect of anti-migratory drugs on tumor cells and the critical influence of interstitial flow than 2D culture models.  相似文献   
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Abstract

Possibility of the previously proposed hinge-opened product 2 of [2+2] C60, dimer 1 transforming itself into IPR C120 fullerenes by a series of generalized Stone-Wales (GSW) rearrangements has been tested by seeking all topologically acceptable pathways with the help of a graphical search program. the first IPR isomer 4 appeared after 20 GSW steps from the wide-bridged dumb-bell shaped precursor 3. More than 1,000 C120 fullerene structures were generated during subsequent ten GSW steps, but the outstanding T d C120 global minimum 5 was not reached. Semiempirical vibrational calculations predict characteristic transition in the vibrational spectra in the course of rearrangement pathway.  相似文献   
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In order to better understand the interactions between cements and superplasticizers (high-range water reducers), various analytical methods have traditionally been applied, but some of these methods can introduce significant errors. In this paper the fundamental interaction mechanisms are reviewed and appropriate methods and sample preparation conditions are explained in detail. For superplasticizer adsorption measurements, analysis by size exclusion chromatography is useful in order to avoid the effect of other organic compounds released from cement by the action of the superplasticizer. For BET specific surface area measurements it is important to avoid pre-drying at over 60 °C, as otherwise ettringite can decompose and strongly increase the surface area. In order to evaluate pore solution chemistry correctly the aqueous phase must be extracted without dilution. In addition, the fluidity performance of many cements in superplasticized concretes can be changed simply by passage through a storage silo, for reasons which are not yet understood.  相似文献   
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This paper describes an attempt to correlate the nature of polar-polar interaction between the reinforcement and matrix in a polymer composite with the boundary phase structure formed in contact with the reinforcement. It is shown by analyzing the mechanical dispersion data that the reinforcement-matrix interaction of Kevlar fiber reinforced poly(hydroxypropyl ether of bisphenol A) (P) is increased by blending poly(ethylene oxide) (E) or poly(ethylene adipate) (A) as a part of matrix, and that E is more efficient than A for the increase of the interaction. These results can be supported at the molecular level from the inspection of the Fourier transform infrared spectra on the Kevlar fiber coated with matrix polymers and the mixture of matrix polymers with benzanilide, which is used as a model compound of Kevlar fiber. It can be shown from the electron spectroscopy for chemical analysis on the films of PIE and P/A blend polymers formed on nylon 6 substrate (N), which is also used as a model material for the reinforcement, that A concentrates on the N-facing side for P/A film and that E concentrates on the air-facing side for PIE film. This result indicates the different susceptibility between P/A and PIE blends to the surface force from N, and hence, it likewise indicates the different interaction with the reinforcement in each blend, as shown by the mechanical dispersion data.  相似文献   
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