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91.
Manjunatha H  Srinivasan K 《Lipids》2007,42(12):1133-1142
Health beneficial hypolipidemic and antioxidant influences of dietary spice principles—curcumin, capsaicin alone and in combination included in the diet for 8 weeks were evaluated in induced hypercholesterolemic rats, in order to verify if there is any additive or synergistic effect of these two bioactive compounds. Dietary curcumin (0.2%), capsaicin (0.015%) or their combination significantly countered the hypercholesterolemia brought about by high cholesterol feeding. Hepatic cholesterol was lowered by dietary spice principles only in normal rats. Liver triglyceride levels were lowered in both normal and hypercholesterolemic rats by capsaicin. Curcumin and capsaicin lowered hepatic and blood lipid peroxides in hypercholesterolemic rats, while the effect in blood was additive with their combination. Hepatic ascorbic acid was enhanced by dietary spice principles in normal rats; glutathione was enhanced by their combination only in hypercholesterolemic rats. Activities of serum glutathione reductase, glutathione transferase and catalase and hepatic glutathione reductase in normal rats and serum glutathione peroxidase in hypercholesterolemic rats were enhanced by dietary spice principles. While dietary curcumin and capsaicin normalized the changes in the levels of antioxidant molecules and activities of antioxidant enzymes to a significant extent, this effect was not generally additive when given in combination, and was higher than the individual effects only in a few instances.  相似文献   
92.
We have proposed a pocket formula for mass attenuation coefficient(μ/ρ), mass energy absorption coefficient(μ_(en)/ρ), and effective atomic number(Z_(eff)) in different tissues of human organs. We have also assigned a new chemical formula for all studied tissues based on their composition. We have introduced a new parameter called effective composition index(C_(eff)). Based on this, we have introduced a new method to compute the effective atomic number. The evaluated photon interaction parameters are graphically represented. The evaluated average, maximum,minimum, and standard deviations of effective atomic number are tabulated. The proposed formula produces a mass attenuation coefficient, mass energy absorption coefficient, and effective atomic number from their composition  相似文献   
93.
AgBr acts as a good sensitizer for titanium oxide, hence TiO2–AgBr nanoparticles exhibit high photocatalytic activity which helps decompose methyl orange under visible light irradiation. Methyl orange is a chemical compound that is hard to degrade and has high stability. It is photoreactive and can capture photons from the sun and is highly used as a light harvester in solar cells, hence, it is used in solar applications. In view of this, the present article deals with the analysis of heat transfer in a multilayer flow of two immiscible nanofluids in a vertical channel that finds application in the fields of solar reactors, electronic cooling, and so on. The mathematical model involving the effect of thermal radiation and the presence of heat source is in the form of a system of ordinary differential equations. This system of equations is simplified using the differential transform method-Padé approximant and the resulting equations are solved algebraically. It is observed that the temperature of the coolant does not reach its saturation point faster due to the presence of different base fluids that differ in their thermal conductivity. This helps in maintaining the optimum temperature of the system.  相似文献   
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A new donor–acceptor-type poly[3-{5-[3,4-didodecyloxy-5-(1,3,4-oxadiazol- 2-yl)thiophen-2-yl]-1,3,4-oxadiazol-2-yl}-9-dodecyl-9H-carbazole] (P) has been synthesized through multistep reactions. The new polymer P exhibited good thermal stability and film-forming behavior. The electrochemical band gap is estimated to be 2.15 eV. The polymer emits intense green fluorescence in the solid state. Third-order nonlinear optical (NLO) studies showed that the strong absorptive nonlinearity observed for the polymer is of the optical limiting type, which is due to an “effective” three-photon absorption (3PA) process. This 3PA process can have potential applications in photonic devices. The studies revealed that the new polymer P is a promising material for development of efficient optoelectronic devices.  相似文献   
96.
Convective heat transfer plays a central role in the numerous industrial devices because it perturbs the mechanical behavior of a system along with its thermodynamics. Keeping such applications in mind, analysis of heat transportation in three‐dimensional tangent hyperbolic fluid flow is investigated here. Convective heat transportation at the boundaries is considered. Rosseland's approximation has been used for the radiation effects. Closed form analytical solutions for the governing equations are difficult to obtain even after the use of similarity transformations. Therefore, the numerical solutions are presented through the Runge‐Kutta‐Fehlberg forth‐fifth method. Graphical analysis of the numerical results has been carried out. Roles of sundry constraints on flow are studied. It is also noted that the rates of heat transportation and skin‐friction are higher in the presence of convective heat transfer near the boundary.  相似文献   
97.
Nanosized particles have become the focus of attention of researchers due to their outstanding optical properties as compared to those of bulk materials. The optical properties can be tuned or tailored if these nanocrystals of right materials are grown on a suitable host matrix. In this paper, a novel method of incorporating inorganic/organic crystals in a polymer matrix and the study of their optical properties are presented. By controlling the level of saturation of the solution and the rate of evaporation, an attempt has been made to incorporate nanocrystals in the host polymer. Inorganic material Potassium di-hydrogen phosphate (KDP) has been chosen because of its versatile properties and applications. Polyvinyl alcohol (PVA) is the host matrix since it has good aqueous solubility and exceptional transparency. The prepared samples, thin nanocrys-tals in a polymer sheet, have been characterised by various spectroscopic techniques such as X-ray diffraction (XRD), UV-vis spectrometer, Fourier Transform Infrared Spectroscopy (FT-IR) and scanning electron microscopy (SEM).  相似文献   
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Camptothecin (CPT), a monoterpene indole alkaloid, is a potent inhibitor of eukaryotic topoisomerase I (Top 1). Because of this property, several derivatives of CPT are widely used as chemotherapeutic agents. The compound is produced by several plant species, including Nothapodytes nimmoniana (Family: Icacinaceae) presumably as a deterrent to insect pests. Here, we report, a lepidopteran larva, Lymantria sp. of Lymantriidae family which feeds voraciously on the leaves of N. nimmoniana, without any adverse consequences. Larval body weight and molting period were unaffected despite captive feeding of the larva with CPT enriched leaves. Mass spectrometric analysis indicated that nearly 46% of the ingested CPT was excreted while the rest was sequestered predominantly in the exuviae and setae (~35%). Although most of the CPT was in the parental form as found in the plant, traces of inactive, sulfated forms of CPT were recovered from the larva. Compared to that in plant, there were no critical mutations at the CPT binding domain of the insect’s Top 1. The gut pH of the larva was alkaline (pH 10.0). The alkaline gut environment converts CPT from its active, lactone form to inactive, carboxylate form. It is likely that such conversion might help the larva to reduce the overall burden of CPT in its gut. We discuss the results in the context of the mechanisms of resistance adapted by insects to plant toxins.  相似文献   
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