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111.
Hirofusa Shirai Kenji Hanabusa Toshiki Koyama Hisanaga Tsuiki Etsuko Masuda 《Macromolecular Symposia》1992,59(1):155-162
The oxidation of HO-CH2-CH2-SH (RSH) by molecular oxygen and Fe(III)- as well as Co(II)-multicarboxyphthalocyanine and the mechanism in homogeneous aqueous system were investigated. As application to enzyme-like heterogeneous catalysts, Fe(III)-as well as Co(II)-octacarboxyphthalocyanine were supported on amorphous enriched rayon staple fiber and their enzyme-like activities were estimated. These fibers were applicated to new odor-removers acting as artificial enzyme systems. 相似文献
112.
Ying An Masahiro Suzuki Toshiki Koyama Kenji Hanabusa Hirofusa Shirai Mei-Yu Huang Ying-Jan Jiang 《先进技术聚合物》1996,7(8):652-656
The palladium cluster protected by silica-supported, crosslinking, partially phosphorylated poly(vinyl alcohol) (P-PVA) was prepared from a crosslinking P-PVA–Pd(II) complex by reduction in alcohol. The P-PVA–Pd complex and the palladium cluster protected by P-PVA were analyzed by electron spectroscopy, X-ray photoelectron spectrometry and transmission electron microscopy. The complex formation between the Pd(II) ion and phosphoric acid groups in P-PVA was important in the formation of a fine palladium cluster. Palladium clusters protected by silica-supported crosslinking P-PVA were used as catalysts for the hydrogenation of nitrobenzene or acrylic acid at 30°C under atmospheric pressure. The palladium cluster protected by crosslinking P-PVA supported on silica was the most active catalyst, was stable and had no by-products, compared with the palladium cluster protected by silica-supported noncrosslinking P-PVA or PVA. 相似文献
113.
Yasushi Koyama Ichiro Takatsuka Munetaka Nakata Mitsuo Tasumi 《Journal of Raman spectroscopy : JRS》1988,19(1):37-49
Raman and infrared spectra in the region of 1800-150 cm−1 were recorded for a set of cis-trans isomers of d̃-carotene, i.e. the all-trans, 7-cis, 9-cis, 13-cis and 15-cis isomers. Spectral comparison revealed Raman and infrared key bands which (1) distinguish stretched or terminal-bent configurations (all-trans, 7-cis and 9-cis) from central-bent configurations (13-cis and 15-cis), and (2) distinguish unmethylated 7-cis and 15-cis configuratios. Keybands (1) include Raman bands at 1160 and 1140 cm−1 and infrared bands at 825 and 775 cm−1 (the intensity varies with the position of the cis-bend) Key bands (2) include Raman bands at 1274 and 962 cm−1 and an infrared band at 741 cm−1 (characteristic of the 7-cis configuration), and also a Raman band at 1247 cm−1 and an infrared band at 775 cm−1 (characteristic of the 15-cis configuration). The normal modes for the key bands were determined by a set of normal coordinate calculations for the isomeric configurations of a simplified model of d̃-carotene. The key bands were mainly related to the C H in-plane bendings, coupled with the CC or C C stretching, or to the C H out-of-plane wagging vibrations, some of which coupled with the CC torsion. 相似文献
114.
Mengxing Cui Ryuichi Murase Yongbing Shen Tetsu Sato Shohei Koyama Kaiji Uchida Tappei Tanabe Shinya Takaishi Masahiro Yamashita Hiroaki Iguchi 《Chemical science》2022,13(17):4902
Electrical conduction among metallocycles has been unexplored because of the difficulty in creating electronic transport pathways. In this work, we present an electrocrystallization strategy for synthesizing an intrinsically electron-conductive metallocycle, [Ni6(NDI-Hpz)6(dma)12(NO3)6]·5DMA·nH2O (PMC-hexagon) (NDI-Hpz = N,N′-di(1H-pyrazol-4-yl)-1,4,5,8-naphthalenetetracarboxdiimide). The hexagonal metallocycle units are assembled into a densely packed ABCABC… sequence (like the fcc geometry) to construct one-dimensional (1D) helical π-stacked columns and 1D pore channels, which were maintained under the liberation of H2O molecules. The NDI cores were partially reduced to form radicals as charge carriers, resulting in a room-temperature conductivity of (1.2–2.1) × 10−4 S cm−1 (pressed pellet), which is superior to that of most NDI-based conductors including metal–organic frameworks and organic crystals. These findings open up the use of metallocycles as building blocks for fabricating conductive porous molecular materials.Intrinsically electron-conductive metallocycle was synthesized. π-Radicals play a key role in constructing π-stacked columns among molecular hexagons and achieving high electrical conductivity over 10−4 S cm−1 in polycrystalline pellet. 相似文献
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118.
Sato S Ogura Y Miyanaga A Sugimoto T Tanaka K Moriyama H 《Journal of chromatography. A》2002,956(1-2):53-58
Ion chromatography (IC) has been a powerful tool for measuring ionic species in environmental samples such as tap, river and drain waters. Suppressor modules (membrane and disposable column types) have been used for reducing the background of a baseline. A new type of suppressor device, which has a suppressor resin and switching valve was developed. Fresh ionic resin is introduced into a groove for each analysis to perform the suppression of the working eluent. The eluent composition for obtaining higher sensitivity and better resolutions among ionic species and carbonate ion was also investigated. Although carbonate buffers are used for ion separation in general, the separation of carbonate ion from other ions was not achieved. A borate eluent resulted in good resolutions and higher sensitivity. A new column was also developed for obtaining higher column efficiency and resolution. The optimization of anion separation using a new IC system (IC-2001) that consists of a new suppressor device, an anion-exchange column (TSKgel SuperIC-Anion, 150x4.6 mm), an autosampler, a conductivity cell and a pump in a compact module is described. 相似文献
119.
Exposure of tertiary thioamides to (E)-1-hexenyl(phenyl)-lambda 3-iodane results in vinylic SN2 reaction to give the inverted (Z)-S-vinylthioimidonium salts, which under alkaline hydrolysis (Na2CO3 or K2CO3) selectively afford amides, while (Z)-S-vinyl thioesters are obtained in high yields via the hydrolysis under acidic conditions (HCl). 相似文献
120.
Periodic mesoporous benzene-silicas with large pores of 6.0 to 7.4 nm in diameter are synthesized using triblock copolymer as a template. These mesoporous materials have a well-defined hexagonal rod morphology and high thermal stability up to 823 K in air. 相似文献