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1.
Repeated administration of highly purified eicosapentaenoic acid (as ethyl ester) resulted in a decrease in plasma triglycerides and high density lipoprotein (HDL) cholesterol. This was accompanied by a stimulation in the activities of carnitine palmitoyltransferase, fatty acyl-CoA oxidase and peroxisomal β-oxidation in the liver. The results suggest that the triglyceride-lowering effect observed with eicosapentaenoic acid may be due to a reduced supply of fatty acids for hepatic triglyceride synthesis because of increased fatty acid oxidation. Eicosapentaenoic acid feeding marginally affected the triglyceride content of heart and mitochondrial and peroxisomal enzyme activities.  相似文献   
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Abstract

We discuss sequential estimation of AR(p) models from the viewpoint of information geometry.  相似文献   
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The cloud index is an important component of the Heliosat algorithm, which estimates solar radiation components from Meteosat High Resolution Visible images. The cloud index quantifies the reflective properties of the atmosphere, and varies from 0 at clear conditions to 1 at overcast. The algorithm is semi-empirical in the way that it includes several constants that need to be tuned. Some of these were removed in the Heliosat-II algorithm where the Meteosat calibration constant was introduced to replace the “pseudo-reflectivity” with a “real reflectivity”. This approach is followed here, and two additional changes are made: (1) An analytical expression is introduced to correct for backscattered radiation from air molecules. (2) A correction is made for non-lambertian reflectivity, removing the time consuming need for determining the ground reflectivity for each month and each slot. The new cloud index is used to calculate global irradiances which are validated against hourly measurements from five European ground stations. The average root mean square deviation is 15.5% for a six-month spring/summer period, of comparable accuracy as using the more time consuming traditional algorithm used in the EU project Satel-Light.  相似文献   
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This paper presents a triac converter which can replace two thyristor bridges normally used for regenerative dc motor drives. The most important characteristics of the triac are outlined and specific problems are discussed. Performance specifications for the control electronics are given. An experimental drive is presented and some run measurements are shown.  相似文献   
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A cellular automaton (CA)-finite element (FE) model and a phase field (PF)-FE model were used to simulate equiaxed dendritic growth during the solidification of hexagonal metals.In the CA-FE model,the conservation equations of mass and energy were solved in order to calculate the temperature field,solute concentration,and the dendritic growth morphology.CA-FE simulation results showed reasonable agreement with the previously reported experimental data on secondary dendrite arm spacing (SDAS) vs cooling rate.In the PF model,a PF variable was used to distinguish solid and liquid phases similar to the conventional PF models for solidification of pure materials.Another PF variable was considered to determine the evolution of solute concentration.Validation of both models was performed by comparing the simulation results with the analytical model developed by Lipton-Glicksman-Kurz (LGK),showing quantitatively good agreement in the tip growth velocity at a given melt undercooling.Application to magnesium alloy AZ91 (approximated with the binary Mg-8.9 wt% Al) illustrates the difficulty of modeling dendrite growth in hexagonal systems using CA-FE regarding mesh-induced anisotropy and a better performance of PF-FE in modeling multiple arbitrarily-oriented dendrites growth.  相似文献   
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From available tables simple formulas are developed for the Rayleigh downward-scattering ratio, and for the atmospheric Rayleigh reflectance to isotropic diffuse irradiance.  相似文献   
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Mechanical properties of yttria-stabilized tetragonal zirconia (YSTZ) bicrystals under compressive loading are investigated by atomistic simulations. Previous studies on deformation of single-crystal YSTZ showed that some specific orientations promote dislocation emission, tetragonal to monoclinic phase transformation, or both. In this work, nanograins with different orientations are selectively combined to generate bicrystals with various grain boundaries (GBs). Simulation results show that regardless of orientation of nanograins, the strength of YSTZ bicrystals is higher when the GB plane is parallel to the loading direction, and in the case of [011]/\( \left[ {01\bar{1}} \right] \)-oriented YSTZ bicrystal, the strength even exceeds that of the single crystal. Independent plastic deformation of individual grains and their interactions at the GB plane are believed to be responsible for the observed increase in strength. GB plane inhibits the volume expansion of transformed monoclinic phase and therefore serves as a source of strengthening. In contrast, YSTZ bicrystal displays softer behavior when GB plane is perpendicular to the loading direction. GB plane acts as the source of softening by initiating local amorphous phase formation.  相似文献   
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A phase-field model was used to investigate the simultaneous effects of grain boundary energy anisotropy and the presence of second-phase particles on grain growth in polycrystalline materials. The system of grains with anisotropic grain boundary energies was constructed by considering models of low and high misorientation angles between adjacent grains. Systems without particles reached a steady state grain growth rate, and this rate decreased by including the grain boundary energy anisotropy. In addition, the presence of particles significantly altered the microstructures during grain growth. This study showed that for systems including particles, the critical average grain size to stop grain growth depends not only on the volume fraction and size of particles, but also on the grain boundary energy anisotropy.  相似文献   
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