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101.
A Rh-doped SrTiO(3) (SrTiO(3):Rh) photocatalyst electrode that was readily prepared by pasting SrTiO(3):Rh powder onto a transparent indium tin oxide electrode gave a cathodic photocurrent under visible-light irradiation (λ > 420 nm), indicating that the SrTiO(3):Rh photocatalyst electrode possessed p-type semiconductor character. The cathodic photocurrent increased with an increase in the amount of doped Rh up to 7 atom %. The incident-photon-to-current efficiency at 420 nm was 0.18% under an applied potential of -0.7 V vs Ag/AgCl for the SrTiO(3):Rh(7 atom %) photocatalyst electrode. The photocurrent was confirmed to be due to water splitting by analyzing the evolved H(2) and O(2). The water splitting proceeded with the application of an external bias smaller than 1.23 V versus a Pt counter electrode under visible-light irradiation and also using a solar simulator, suggesting that solar energy conversion should be possible with the present photoelectrochemical water splitting. 相似文献
102.
Maehara S Ikeda M Haraguchi H Kitamura C Nagoe T Ohashi K Shibuya H 《Chemical & pharmaceutical bulletin》2011,59(8):1042-1044
We investigated the microbial conversion of curcumin (1) using endophytic fungi associated with the rhizome of Curcuma longa (Zingiberaceae). We found that Diaporthe sp., an endophytic filamentous fungus, converts curcumin (1) into four colorless derivatives, namely (3R,5R)-tetrahydrocurcumin (2), a novel (3R,5S)-hexahydrocurcumin (3) named neohexahydrocurcumin, (3S,5S)-octahydrocurcumin (4) and meso-octahydrocurcumin (5). 相似文献
103.
Mallik AK Qiu H Sawada T Takafuji M Ihara H 《Chemical communications (Cambridge, England)》2011,47(37):10341-10343
A molecular gel system was assembled on carrier particles and the integrated effect of weak interaction sites enabled highly efficient separation of the bioactive and shape-constrained isomers of tocopherols, β-carotene, and polycyclic aromatic hydrocarbons (PAHs) by multiple interaction mechanisms. 相似文献
104.
105.
M Shibasaki A Takahashi T Aoki H Sato S Yamada M Kudo K Kogi S Narita 《Chemical & pharmaceutical bulletin》1992,40(1):279-281
A synthesis of a novel and chemically stable homoisocarbacyclin analog, TY-11223 (3), has been accomplished. The analog (3), given intravenously or orally, showed potent and long-lasting activities in inhibiting platelet aggregation and, in addition, a good selectivity in biological activities. 相似文献
106.
Osamu Yamashita Kouji Satou Hirotaka Odahara Shoichi Tomiyoshi 《Journal of Physics and Chemistry of Solids》2005,66(7):1287-1293
The p-type (Bi0.25Sb0.75)2Te3 doped with 3-12 wt% excess Te alone and n-type Bi2(Te0.94Se0.06)3 codoped with 0.017-0.026 wt% Te and 0.068-0.102 wt% I were prepared by the Bridgman method, to produce intentionally polycrystalline. Some of the as-grown specimens were annealed, in order to prepare specimens with much different ρ. These polycrystalline specimens have almost the same degree of alignment of the c plane parallel to the freezing direction. The electrical rersistivity ρ and thermal conductivity κ were measured at 298 K along the freezing direction and κ was plotted as a function of ρ. As a result, the lattice components κph obtained by subtracting the electronic component κel from the observed κ were found to decrease almost linearly with a decrease of ρ in both p- and n-type specimens, where κel was calculated using Wiedemann-Franz law. This tendency is consistent with the conventional result that κph becomes negligible small in metals. The significant decrease in κph with decrease in ρ is considered to be caused predominantly by the phonon scattering due to dopants. The relationship between κph and ρ was first clarified in the intermediate region between the metal and insulator. 相似文献
107.
108.
Atsuomi Shundo Megumi Fukui Makoto Takafuji Kazuaki Akasaka Hiroshi Ohrui Dusan Berek Hirotaka Ihara 《Analytical sciences》2007,23(3):311-315
2-(2,3-anthracenedicarboximido)cyclohexane derivatives (AC) have been known as the evolutionary diastereomerizing reagents for enantiomer discrimination in HPLC with ODS. However, a substantial separation of diastereomers can be observed only at lower temperatures, such as -40 degrees C. Therefore, in this work, poly(octadecyl acrylate)-grafted silica, ODAn was applied as an alternative stationary phase to ODS for the separation of AC-derived diastereomers. As a result, complete separation was achieved even under the conventional condition: for example, methanol as the mobile phase and 0 degrees C as the column temperature. An investigation on the temperature dependency of the selectivity demonstrated that ODAn shows a remarkable increase in selectivity at temperatures below 30 degrees C, which almost agreed with the peak-top temperature of the endothermic peak in a DSC thermogram for ODA35 immersed in a mobile phase. The better separation would be derived from a highly ordered structure of ODAn and a carbonyl-pi interaction with AC-derived diastereomers. 相似文献
109.
Inelastic scattering of 80 MeV deuterons from 58Ni and 120Sn is analyzed in terms of an adiabatic coupled-channels Born approximation (ACCBA) method. The ACCBA method is a practical means to treat deuteron plus nucleus as a three-body system. Inclusion of the breakup modes significantly reduces the inelastic cross section. The significance of considering both the s-wave and d-wave breakup modes is pointed out. 相似文献
110.
The dechannelling cross section of a circular Frank dislocation loop of radius 19 Å, and of Burgers vector (a/3)(111) in gold crystal is calculated for (001) channeling of 2 MeV He+. The calculated value σc = 210 ± 10 Å2 is satisfactory compared with the experimental value σe = 235 Å2 by Merkel et al. 相似文献