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51.
Yoshihiro Kon Toshiyuki Yokoi Masato Yoshioka Shinji Tanaka Yumiko Uesaka Takehisa Mochizuki Kazuhiko Sato Takashi Tatsumi 《Tetrahedron》2014
Selective oxidation of sulfides to sulfoxides and sulfones with hydrogen peroxide under organic solvent-free conditions was demonstrated by the MWW-type titanosilicate zeolite catalyst. Sulfides were oxidized smoothly to give sulfoxides with good selectivities at ambient temperature using 1.0–1.2 equiv of hydrogen peroxide with the MWW-type titanosilicate zeolite catalyst. Especially, the Ti-MWW with an interlayer-expanded structure (Ti-IEZ-MWW) catalyst showed high activity with good chemoselectivity for the oxidation of various sulfides. The catalyst is recyclable for at least five cycles, and the only byproduct is water. Sulfides were directly oxidized to give sulfones in high yields by 2.5 equiv of hydrogen peroxide with the MWW-type titanosilicate zeolite catalyst under organic solvent-free conditions. 相似文献
52.
N. S. Takahashi Y. Hunyu E. Shibano N. Mochizuki S. Kurita 《Crystal Research and Technology》1993,28(5):711-716
The fabrication and characterization of double-heterostructure (DH) laser that utilizes an indium-tin oxide (Ito) transparent cladding and top contact layer. The first room-temperature lasing operation has been obtained form ITO/InGaAsP/AlGaAs DH laser diode at threshold current density of 12.1 kA/cm2. The interfacial recombination velocity of ITO/InGaAsP Interface was estimated to be 4.9 × 104 cm/s from a simple model to account for high threshold current, and optical measurements of spontaneous emission and lasing spectra from top stripe window and facet were done. 相似文献
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56.
Okuda K Abeta C Hirota T Mochizuki M Mashino T 《Chemical & pharmaceutical bulletin》2002,50(7):985-987
Water-soluble C60-porphyrin hybrid molecules were first synthesized toward their pharmaceutical applications. 相似文献
57.
Yoko Usami 《Journal of Graph Theory》1985,9(2):221-234
Suppose G is a graph of n vertices and diameter at most d having the property that, after deleting any vertex, the resulting subgraph has diameter at most 6. Then G contains at least max{n, (4n - 8)/3} edges if 4 ≤ d ≤ 6. 相似文献
58.
Suzuki Y Sarachik MP Chudnovsky EM McHugh S Gonzalez-Rubio R Avraham N Myasoedov Y Zeldov E Shtrikman H Chakov NE Christou G 《Physical review letters》2005,95(14):147201
Local time-resolved measurements of fast reversal of the magnetization of single crystals of Mn12-acetate indicate that the magnetization avalanche spreads as a narrow interface that propagates through the crystal at a constant velocity that is roughly 2 orders of magnitude smaller than the speed of sound. We argue that this phenomenon is closely analogous to the propagation of a flame front (deflagration) through a flammable chemical substance. 相似文献
59.
Hiraoka K Asakawa Y Kawashima Y Okazaki S Nakamura M Yamamoto Y Takamizawa A 《Rapid communications in mass spectrometry : RCM》2004,18(20):2437-2442
The effect of the presence of foreign salts (NaCl, aerosol OT, tetra-n-hexylammonium bromide, and CH3COONH4) on the formation of gaseous ions for electrospray (ES) and laser spray (LS) was studied in the positive and negative modes of operations. The ion signals for amino acids show sudden decrease with the concentration of foreign salts greater than 10(-5) M for both ES and LS. When the surface-active counter ions were added, the signal intensities showed a marked decrease for both ES and LS. This may be due to the enrichment of the surface-active counter ions on the surface of the charged droplets. When CH3COONH4 was added to an aqueous solution of 10(-6) M lysozyme chloride, an increase of the signal intensities for (lysozyme+nH)n+ and a decrease in the values of n were observed. The decrease in n may be due to the salt formation of (lysozyme+nH)n+ with the negative acetate ion leading to the reduction of positive charges. 相似文献
60.
An HPLC assay of hydroxyl radicals by the hydroxylation reaction of terephthalic acid 总被引:2,自引:0,他引:2
Linxiang L Abe Y Nagasawa Y Kudo R Usui N Imai K Mashino T Mochizuki M Miyata N 《Biomedical chromatography : BMC》2004,18(7):470-474
An HPLC assay for hydroxyl radicals is described. The hydroxyl radical was trapped by terephthalic acid (non-fluorescent), and 2-hydroxyl terephthalic acid (fluorescent) was quantitated by HPLC-fluorescence detection. At a terephthalic acid concentration of 4.25 mmol/L, the hydroxyl radical formed in the Fenton reaction was successfully assayed in the concentration range of hydrogen peroxide of 2.5-50 micro mol/L, where the concentration of Fe(II) was 50 micro mol/L. The fluorescence of 2-hydroxy terephthalate was stable at 24 h, and its detection limit by this method was 5 nmol/L (100 fmol). 相似文献