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Nitrogen-doped titania nanoparticles consisted of pure anatase, rutile and brookite phases were successfully prepared by a solvothermal process in TiCl3-HMT (hexamethylenetetramine, C6H12N4)-alcohol mixed solution. The powders were yellow or beige and showed excellent visible light absorption and photocatalytic ability for the oxidative destruction of nitrogen monoxide under irradiation of visible light of wavelength >510 nm.  相似文献   
104.
Despite a large interest in plasma-assisted catalytic technology (PACT), very little has been reported about the catalytic effects of different dielectric barriers on a dielectric barrier discharge (DBD) reaction. In the present study, Ca0.8Sr0.2TiO3, that possesses a high permittivity, was prepared by liquid phase sintering and used as a dielectric barrier in a DBD reactor to break CO2. The mechanical and dielectric properties of Ca0.8Sr0.2TiO3 were greatly enhanced by adding 0.5 wt.% Li2Si2O5. A DBD plasma was successfully generated by using this Ca0.8Sr0.2TiO3 as a dielectric barrier and 18.8% CO2 conversion was achieved with the residence time of 0.17 s at the frequency of 8 kHz, which was much higher than with those using an alumina or a silica glass barrier. It was found that the plasma power increased with the increasing of the permittivity, and finally very dense and strong microdischarges were initiated to decompose CO2.  相似文献   
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An improved vacuum nebulizing interface with a very short counter nozzle was developed for direct coupling of a micro-LC and a quadrupole MS with CI-chamber. With the LC-MS system using the nebulizing interface, it became possible to take mass fragmentograms for various less volatile compounds such as glutamic acid, steroids, aromatic amines and chlorine-containing insecticides.  相似文献   
107.
A novel photocatalytic material (Pt,Cd0.8Zn0.2S)/HLaNb2O7 was fabricated by successive intercalation and exchange reactions. The (Pt,Cd0.8Zn0.2S)/HLaNb2O7 possessed a gallery height less than 0.5 nm and showed a broad absorption with wavelength over 370-500 nm. Using (Pt,Cd0.8Zn0.2S)/HLaNb2O7 as catalyst, the photocatalytic H2 evolution was more than 160 cm3·h-1·g-1 in the presence of Na2S as a sacrificial agent under irradiation with wavelength more than 290 nm from a 100-W mercury lamp. Furthermore, the catalyst showed photocatalytic activity even under visible light irradiation.  相似文献   
108.
The degree of atomization, β, is measured for an electrothermal atomizer by comparing the emission lines of copper atoms and CuCl molecules. Hydrogen increases the β value. The determined β value of CuCl is used as a standard for the determination of β values of other elements (nickel, chromium, tin and lead).  相似文献   
109.
A major problem in gel permeation chromatography (GPC) or size exclusion chromatography is non-specific binding of applied proteins to the column matrix (stationary phase). We have tested an aqueous arginine solution as the GPC mobile phase on silica-based and polymer-based columns, using mouse monoclonal antibody and recombinant human activin, interleukin-6, basic fibroblast growth factor, and interferon-gamma as model proteins. We observed that addition of arginine to the mobile phase improves separation of the proteins and their soluble aggregates from the GPC columns, which suggests that arginine is an effective additive for the GPC mobile phase.  相似文献   
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Novel pyrimidinyl pyrazole derivatives were synthesized and examined for cytotoxic and antitumor activity. Mannich reaction was employed to construct this scaffold. Among the compounds synthesized, a series of propene derivatives exhibited a potent cytotoxic activity against some tumor cell lines including multidrug resistant cell lines due to the overexpression of P-glycoprotein. The vinyl bond moiety in the scaffold was believed to be required for the cytotoxic activity. Among them, compound 14 g, when administered intraperitoneally, showed potent antitumor activity against the malignant ascites caused by intraperitoneal inoculation of P388 cells in mice. This compound also showed high activity against a solid tumor Meth A mouse fibrosarcoma when administered both intraperitoneally and orally.  相似文献   
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