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31.
The efficiency of using lactic acid (LA) as a surface decontaminator for carcasses contaminated with spinal chord (SC) tissues was evaluated. Four representative places with surface area of 5 × 5 cm, were marked on the inner side of the porcine carcasses. 0.200 μl of 0.5% SC solution was applied to each marked area and separately washed in a specially designed spraying cabinet, which comprises 15 nozzles adjusted to spray 1% LA or tap water with a scatter pressure of 0.49 MPa. Samples were collected after washing for 15, 30, 60 and 90 s and analyzed by Ridascreen kit ELISA test. 1% LA reduces the SC materials to pre-contaminated levels while having negligible effect on the color of carcasses. Furthermore washing with LA insignificantly reduced the total microbial counts. Using very low concentration of LA (1%) in production lines of slaughter houses may help to decontaminate the carcasses to some extent without having adverse impact on quality attributes.  相似文献   
32.
The effect of purple potato flake on cholesterol metabolism was investigated in rats fed a high-cholesterol diet. The hypocholesterolemic action of dietary purple potato flake might be related with caecal fermentation and steroid excretion due to the phosphorus and polyphenols including anthocyanin.  相似文献   
33.
Nickel (Ni) nanoparticles were synthesized in micropores of zeolite by the adsorption and decomposition of a sublimated Ni organometallic compound, Ni(C5H5)2, to invent metallic catalysts with nanosize, which are smaller than 5 nm and keep the nanosize at high temperature. In the decomposition process, Ni species were partially decomposed by ultraviolet light irradiation and fixed in zeolite pores prior to thermal reduction under H2 flow. Note that the Ni nanoparticles showed an excellent thermal stability, because they kept the high dispersion with diameters smaller than 5 nm even after heating at 400 °C. On the other hand, the Ni particles supported on zeolite by a conventional method, which is an incipient wetness impregnation process, became larger than 10 nm after heating at the same temperature. The synthesized Ni nanoparticles acted as a metallic catalyst because they showed higher selectivity for H2 generation than C2H4 generation during ethanol steam reforming reaction.  相似文献   
34.
The effects of dietary conjugated linoleic acid (CLA) and linoleic acid (LA) on ketone body production and lipid secretion were compared in isolated perfused rat liver. After feeding the 1% CLA diet for 2 wk, the concentration of post-perfused liver cholesterol was significantly reduced by CLA feeding, whereas that of triacylglycerol remained unchanged. Livers from CLA-fed rats produced significantly more ketone bodies; and the ratio of β-hydroxybutyrate to acetoacetate, an index of mitochondrial redox potential, tended to be consistently higher in the liver perfusate. Conversely, cumulative secretions of triacylglycerol and cholesterol were consistently lower in the livers of rats fed CLA, and the reduction in the latter was statistically significant. Thus dietary CLA appeared to exert its hypolipidemic effect at least in part through an enhanced β-oxidation of fatty acids at the expense of esterification of fatty acid in the liver.  相似文献   
35.
Fucoxanthin (Fx) is a marine carotenoid with anti-inflammatory and anti-cancer properties in various animal models of carcinogenesis. However, there is currently no information on the effects of Fx in animal models of pancreatic cancer. We investigated the chemopreventive effects of Fx in C57BL/6J mice that received allogenic and orthotopic transplantations of cancer cells (KMPC44) derived from a pancreatic cancer murine model (Ptf1aCre/+; LSL-krasG12D/+). Using microarray, immunofluorescence, western blot, and siRNA analyses, alterations in cancer-related genes and protein expression were evaluated in pancreatic tumors of Fx-administered mice. Fx administration prevented the adenocarcinoma (ADC) development of pancreatic and parietal peritoneum tissues in a pancreatic cancer murine model, but not the incidence of ADC. Gene and protein expressions showed that the suppression of chemokine (C-C motif) ligand 21 (CCL21)/chemokine receptor 7 (CCR7) axis, its downstream of Rho A, B- and T-lymphocyte attenuator (BTLA), N-cadherin, αSMA, pFAK(Tyr397), and pPaxillin(Tyr31) were significantly suppressed in the pancreatic tumors of mice treated with Fx. In addition, Ccr7 knockdown significantly attenuated the growth of KMPC44 cells. These results suggest that Fx is a promising candidate for pancreatic cancer chemoprevention that mediates the suppression of the CCL21/CCR7 axis, BTLA, tumor microenvironment, epithelial mesenchymal transition, and adhesion.  相似文献   
36.
A stable formula using oil-in-water-in-oil (O/W/O) type multiple emulsions was investigated. The components consisted of hydrophilic nonionic surfactant (HCO-60), organophilic montmorillonite, and lipophilic nonionic surfactant (DIS-14). O/W/O emulsions were prepared by a double-step procedure in which an O/W emulsion was prepared in the first step, and then the O/W emulsion was “re-emulsified” in an oil phase with organophilic montmorillonite. The diameter of the innermost oil droplets decreased with increasing HCO-60 content (0.1–3%), while the viscosity showed a maximum at 1% of HCO-60, indicating that the yiel of re-emulsification is highest at this condition. Viscosity of the O/W/O emulsion increased with increasing organophilic montmorillonite and DIS-14. According to the results of a phase ratio study, viscosity and stability of the O/W/O emulsion decreased at high weight fraction of inner oil phase (0.4–0.5), indicating that the excess amount of inner oil phase is absorbed by the outer oil phase. These results revealed that the weight fraction of inner oil phase should be kept below 0.3 for a stable O/W/O emulsion. A similar study on the weight fraction of O/W phase [фO/W)/O] suggested that the O/W/O emulsion is stable at ϕ(O/W)/O=0.65–0.70.  相似文献   
37.
Discharge induction experiments were performed between a plate and a rod on a plate electrode configuration with a gap length of 1 m using a high‐power CO2 laser and a dc voltage generator. The electrodes are parallel planes. Each plate electrode consists of a central flat part having a diameter of 3 m with a circular edge on a cross section. The length of the rod is 10 cm. A chain of plasma beads of length 10 cm was created on the tip of the rod by the CO2 laser and used for artificial triggering of negative high‐voltage sparkover. The behavior of streamer, leader, and return stroke was observed by an image converter camera. It was found that a positive upward traveling leader can be triggered from the tip of the rod on the lower plane to the upper plane by the chain of plasma beads created by the CO2 laser. This apparatus is useful for study for realization of laser‐induced lightning. © 2000 Scripta Technica, Electr Eng Jpn, 132(4): 19–27, 2000  相似文献   
38.
A novel electrochemical route was developed for reduction of the superconducting Bi2Sr2CaCu2O8+δ compound (Bi-2212) in the over-hole-doped state, which was undertaken employing an electrolyte solution consisting of benzoic acid dissolved in acetone. The reduction gave rise to enhancement of the critical temperature ( TC ) of Bi-2212 up to 90 K. This reduction effect on TC corresponded to the effect of annealing at elevated temperatures in reducing atmospheres. It appears that protons from the benzoic acid carboxyl groups were responsible for the reduction of the Bi-2212. Structural stability of the electrochemically reduced Bi-2212 was different from that of Bi-2212 annealed in reducing atmospheres.  相似文献   
39.
Chemical artifact is a problem in the sampling of atmospheric organic species for a relatively long sampling period. In this study, we evaluated a technique for the removal of atmospheric oxidants with added NO during gas and aerosol sampling by theoretical approach using a Regional Atmospheric Chemistry Mechanism (RACM) model. The elimination of O3 in the sample air is regulated predominantly by the reaction of NO and O3 in all simulated cases. We found that, without any oxidant scavenger, OH and NO3 concentrations in the sampler can be kept high even when wall loss processes of radicals are taken into account The relatively high concentration of OH is mainly due to the production of HO(x) in the sample air via the decomposition of HO2NO2 and O3-olefin reactions, whereas NO3 is produced by the decomposition of N2O5. Addition of NO with appropriate concentrations was found to effectively reduce both OH and NO3 concentrations in the sampling devices. This study demonstrates that scavenging of OH and NO3 as well as O3 is important for the study of chemical speciation of organic compounds and that NO addition is a useful technique to eliminate these oxidants.  相似文献   
40.
A wavelength-switching method for tuning a self-injection-seeded Ti3+:sapphire laser that uses an electro-optic beam deflection technique is reported. A LiNbO3 prism was employed in a tuning arm of the dual-cavity Ti3+:sapphire laser, and wavelength tuning of approximately 94 pm was attained by altering the deflection angle with the application of an electric field of 10 kV/cm to the prism. The spectral characteristics of the output laser were mainly determined by the diffraction grating in the dual-cavity laser, and the electro-optic prism just behaved as a light-beam deflector for the wavelength tuning purpose. This configuration can allow a simple tuning approach where fast and stable electronic wavelength switching is required in a narrow tuning range, on an order between a few tens of picometers to nanometers, without involving any mechanical movement.  相似文献   
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