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111.
Environmentally friendly soft chemical processes, including solvothermal/hydrothermal process and mechanochemical process,for the synthesis of mixed anion type visible-lightinduced photocatalysts are introduced in this review paper. Titania and strontium titanate based anion doped photocatalysts can be effectively prepared at such low-temperature as below 200 ℃. Especially,the mechanochemical process is a useful method for the synthesis of various mixed ions doping functional materials at low temperatures. The mixed anion type photocatalytic compounds consisted of N/O, N/F/O, S/O, N/C/O, show excellent visible light absorption ability and photocatalytic activities, indicating the potential applications in environmental purifications. Full-spectra active long wavelength light induced photocatalyst, full-time active photocatalyst system and infrared radiation(IR) shielding multifunctional photocatalysts will be introduced also. 相似文献
112.
Anisotropic structure analyses for [CoOx]/-Al2O3 (0001) and [Co3O4]n /-Al2O3 (0001) which were derived from Co2(CO)8/-Al2O3 (0001) were performed by a polarized total-reflection fluorescence extended X-ray absorption fine structure (EXAFS) technique. Both s- and p-polarized EXAFS data revealed that the cobalt atoms of [CoOx] were located on three-fold hollow sites of -Al2O3 (0001) in a monomer form and that a thin spinel structure [Co3O4] grew with the (001) plane parallel to -Al2O3 (0001). 相似文献
113.
Kouichi Asakura Shuichi Matsumura Sadao Yoshikawa Kazuo Kawada Tsuyoshi Uchibori 《Journal of the American Oil Chemists' Society》1989,66(10):1450-1453
Some phenolic compounds containing both phenolic hydroxyl groups and sulfide groups in the molecules were prepared by Michael
addition and radical addition reactions of ethanethiol and ethanedithiol witho-, m- andp-vinylphenol. The antioxidant effect of these products on the autoxidation of lard was examined by an oven test at 60°C. The
antimicrobial activities of these products were evaluated by an agar dilution method. Three kinds of gram-positive and three
kinds of gram-negative bacterial strains, as well as six kinds of fungal strains were used for the test. It was found that
the Michael addition products showed considerably better antioxidant effects than BHT, whereas the radical addition products
did not show any antioxidant effect. The antioxidant effects of these compounds were influenced by the positions of the sulfide
groups in their molecules. The phenolic sulfides tested in this report showed good antimicrobial activities against bacteria
and fungi. 相似文献
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116.
Electrospinning is a good method to obtain nanoscale fibers from polymer solutions. In this paper, we successfully prepared non-woven nanofibers of Bombyx mori and Samia cynthia ricini silk fibroins, and of the recombinant hybrid fiber involving the crystalline domain of B. mori silk and non-crystalline domain of S. c. ricini silk from hexafluoroacetone (HFA) solution using electrospinning method. 13C cross polarization/magic angle spinning NMR spectroscopy was used to monitor the structural change of silk fibroins together with the detection of the residual HFA during the process of the fiber formation. Scanning electronic microscope was used to determine the diameters and their distributions of the fibers. 相似文献
117.
Seiji Akiyama Mamiko Nakabayashi Naoya Shibata Tsutomu Minegishi Yusuke Asakura Md. Abdulla‐Al‐Mamun Takashi Hisatomi Hiroshi Nishiyama Masao Katayama Taro Yamada Kazunari Domen 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(39):5468-5476
An improved variation of highly active/durable O2‐evolving LaTiO2N powder‐based photoelectrode has been fabricated by pre‐cleaning the powder with mild polysulfonic acid and by homogeneous deposition of CoOx co‐catalyst aided by microwave annealing. The treatment in aqueous solution of poly(4‐styrene sulfonic acid) results in removal of surface LaTiO2N layers, forming fine pores in the crystallites. The CoOx co‐catalyst by microwave deposition in Co(NH3)6Cl3/ethylene glycol homogeneously covers the particle surface. The LaTiO2N powder is fabricated into particle‐transferred electrodes on Ti thin film supported on solid substrate. The modified LaTiO2N grains on the electrode serve as a highly active O2‐evolving photoanode achieving 8.9 mA cm?2 of the photocurrent density at 1.23 V versus reversible hydrogen electrode (RHE) in 0.1 m NaOH (pH 13) under solar‐simulator irradiation Airmass 1.5 Global (AM 1.5G). The activity has been much improved, compared with conventional LaTiO2N treated in mineral acid or with CoOx deposited by impregnation. The new electrode also exhibits better durability in fixed‐potential chronoamperometric tests under AM 1.5G irradiation. 相似文献
118.
The aberration of a multipole Wien filter for energy-filtered x-ray photoemission electron microscopy was analyzed and the optimized Fourier components of the electric and magnetic fields for the third-order aperture aberration corrections were obtained. It was found that the third-order aperture aberration correction requires 12 electrodes and magnetic poles. 相似文献
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120.
Takahashi Y. Asakura Y. 《Electronics Packaging Manufacturing, IEEE Transactions on》2001,24(4):313-322
First, the light intensity (luminance) distributions reflected from quad flat package (QFP) gull wing lead solder fillets were calculated by a simple geometrical model, using a modified diffusion equation. The dependence of the microscope angle &thetas; (= incident angle of light) on the highlight distribution from specular surfaces was obtained. Luminance distributions from top to toe fillets were experimentally observed, using Sn-Pb eutectic solder and two kinds of Pb-free solder (Sn-Ag-Cu and Sn-Zn-Bi systems) and the characteristics were compared with the simulation results. As the Sn-Pb solder fillet has a specular (or smooth) surface, it is not so difficult to identify the profiles of Sn-Pb fillets by changing &thetas;. On the other hand, the luminance distributions for Pb-free solder were strongly affected by the surface roughness. However, it is not impossible to extract the characteristics of the fillet profile if wetting properties of Pb-free solder are taken into consideration. It was found for Pb-free solder that the fillet formation characteristics extraction becomes easy if elements of Bi and In are doped because the wetting properties were improved. In addition, some problems with characteristics extraction of fillet formation for Pb free solder are discussed from the viewpoint of an external feature inspection system 相似文献