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491.
Hiroshi Kominami Katutoshi Sumida Kazuto Yamamoto Nobuaki Kondo Keiji Hashimoto Yoshiya Kera 《Research on Chemical Intermediates》2008,34(5-7):587-601
Various metal chloride-modified titanium(IV) oxide (TiO2) (MCMT) samples were prepared by loading metal chloride on commercial TiO2 nanoparticles (Ishihara ST-01) having a large specific surface area and used for photoinduced oxidative removal of nitrogen oxides (NO x ) in air under irradiation of visible light and/or ultraviolet (UV) light. The NO x removal activity of MCMT samples under photoirradiation from a blue fluorescent lamp (BFL) with a UV cut filter decreased in the following order: RhCl3/ST-01>H2PtCl6/ST-01>RuCl3/ST-01>ST-01>IrCl4/ST-01>HAuCl4/ST-01, indicating that RhCl3. H2PtCl6 and RuCl3 fixed on TiO2 effectively worked as photosensitizers for NO x removal. NO x was almost quantitatively fixed as nitrate on RhCl3/ST-01 photoirradiated with BFL or blue light-emitting diodes. Under irradiation of both visible light and UV light from a white fluorescent lamp, RhCl3/ST-01 exhibited a higher level of removal of NO x and a much lower level of release of nitrogen dioxide than did bare ST-01, indicating that RhCl3/ST-01 effectively utilized both visible light and UV light and that two types of reaction (photosensitization by fixed RhCl3 and photocatalysis by TiO2) occurred over RhCl3/ST-01. 相似文献
492.
Katsumata M Takeuchi A Kazumura K Koike T 《Journal of photochemistry and photobiology. B, Biology》2008,90(3):152-162
A new method for measuring delayed luminescence (delayed fluorescence) employs preillumination and a dark waiting period before normal excitation. The preillumination results in a concavity and a convexity in the decay curve in delayed luminescence in the green alga Pseudokirchneriella subcapitata. Formation of the concavity and the convexity is not affected by excitation wavelength (680 nm and 700 nm). However, the concavity and the convexity progressively decrease as the dark waiting period increases after preillumination. The formation of the concavity and the convexity was inhibited by exposure to the electron transport inhibitors DBMIB (644 μg/L, 2.0 μM) and Antimycin A (55 μg/L, 0.1 μM). Samples exposed to DBMIB exhibited noticeable reduction in the concavity, whereas samples exposed to Antimycin A exhibited pronounced reduction in the convexity. There is a possibility that the formation and disappearance of the concavity and the convexity are due to the reduction–oxidation state of the plastoquinone pool and the cyclic electron transport. We expect this method being useful in evaluating the effects of chemicals (particularly toxic chemicals) on photosynthetic reactions, and the method may also help to resolve questions regarding the source of long delayed luminescence. 相似文献
493.
Hiroyuki Konno Yasuhiro Okuno Kazuto Nosaka Yoshinari Abe Kenichi Akaji 《Tetrahedron letters》2008,49(5):782-785
Total synthesis of cis-solamin A was accomplished without using protecting groups starting from (−)-muricatacin in 11 steps with an overall yield of 4.5%. The backbone of cis-solamin A was constructed by olefin cross-metathesis between the tetrahydrofuran moiety and γ-lactone moiety. An enzymatic kinetic transesterification procedure was successfully applied to the synthesis of an optically pure γ-lactone moiety. 相似文献
494.
The use of an inorganic layered compound as a pseudostationary phase (PSP) in EKC was investigated. A synthetic smectite, which is the most typical swellable clay mineral, with an average diameter of 130 nm was selected as the PSP. The retention characteristics of the smectite and on-line sample concentration by sweeping were examined for the analysis of polyoxyethylene mono phenyl ethers (PPEs) with different degrees of ethoxylation. The retention factor was increased with increase in the number of ethylene oxide groups and a good separation of the PPE homologs was achieved by smectite-EKC. The RSD of the migration time, plate number, and peak area were 0.60, 8.3, and 2.7% (n = 5), respectively. The developed method can be applied to the analysis of PPEs in commercially available consumer products without any sample pretreatments. In addition, ca. 100-fold sensitivity enhancements for the PPEs with high retention factors were obtained by sweeping. 相似文献
495.
496.
Joshi P Carpenter MP Fossan DB Koike T Paul ES Rainovski G Starosta K Vaman C Wadsworth R 《Physical review letters》2007,98(10):102501
A study of the nucleus 106Ag has revealed the presence of two strongly coupled negative-parity rotational bands up to the 19- and 20- states, respectively, which cross each other at spin I approximately 14. The data suggest that near the crossover point the bands correspond to different shapes, which is different to the behavior expected from a pair of chiral bands. Inspection of the properties of these bands indicates a triaxial and a planar nature of rotation for the two structures. Possible causes for this may be understood in terms of a shape transformation resulting from the large degree of gamma softness of 106Ag. These data, along with the systematics of the odd-odd structures in the mass 100 region, suggest that gamma softness has marked implications for the phenomenon of nuclear chirality. 相似文献
497.
498.
499.
Masato Nakano Shugo Atsuumi Yutaka Koike Hajime Morishima 《Journal of carbohydrate chemistry》2013,32(5):695-705
ABSTRACT A transition-state analogue of a renin inhibitor at the scissile site, a dihydroxyethylene isostere of cyclohexylalanine amide, (2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanediol(ACMP), was synthesized from 1,2:5,6-di-O-isopropylidene-α-D-allofuranose stereospecifically. 相似文献
500.
Takahiro Kurashima Koichi Sakuma Takayuki Arai Akihiro Tagaya Yasuhiro Koike 《Optical Review》2012,19(6):415-418
We have demonstrated a polarized laser backlight for liquid crystal displays and have investigated its basic polarization properties. To maintain the state of polarization of light propagating through the light-guide plate (LGP) of the backlight, we fabricated the LGP by injection molding of a zero-zero-birefringence polymer, poly(methyl methacrylate-co-2,2,2-trifluoroethyl methacrylate-co-benzyl methacrylate) (52: 42: 6 by mass) that is free of both orientational and photoelastic birefringence. The degree of polarization of light from the resulting backlight (average: 92.4%) was much higher than that from a backlight with a polycarbonate LGP (average: 8.0%) in the defined effective range of the backlight. A laser speckle pattern was observed but the speckle contrast on the output surface of the backlight was reduced from 68 to 10% by vibrating a diffuser sheet situated in front of the output surface of the LGP. We also manufactured a white surface light source [chromaticity (value: x, y) = (0:310, 0:314)] by mixing the outputs from three primary-color-emitting lasers in the backlight. 相似文献