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排序方式: 共有483条查询结果,搜索用时 15 毫秒
91.
Masaaki Kitano Kazuhiro Iyatani Ebrahimi Afsin Yu Horiuchi Masato Takeuchi So-Hye Cho Masaya Matsuoka Masakazu Anpo 《Research on Chemical Intermediates》2012,38(6):1249-1259
Visible light-responsive TiO2 (Vis-TiO2) thin films able to absorb UV and visible light in wavelength regions of 250–600 nm were successfully developed by applying
a radio-frequency magnetron sputtering deposition method. These Vis-TiO2 thin films exhibited high activity for the photocatalytic oxidation of 2-propanol diluted in water even under visible light
irradiation (λ ≥ 450 nm). The photocatalytic activity of Vis-TiO2 thin films was dramatically enhanced by the deposition of Pt particles on the surface. Secondary ion mass spectrometry measurements
revealed that Pt particles are distributed from the top surface to the deep bulk of Vis-TiO2 thin films with a columnar structure. The unique columnar structure of Vis-TiO2 thin films plays an important role in the high photocatalytic performance. 相似文献
92.
93.
Prof. Takahisa Omata Aman Sharma Prof. Issei Suzuki Tomohiro Ishiyama Shinji Kohara Koji Ohara Prof. Madoka Ono Prof. Yang Ren Khurelbaatar Zagarzusem Prof. Masaya Fujioka Prof. Gaoyang Zhao Prof. Junji Nishii 《Chemphyschem》2022,23(3):e202100840
Anhydrous silicophosphoric acid glass with an approximate composition of H5Si2P9O29 was synthesized and its thermal and proton-conducting properties were characterized. Despite exhibiting a glass transition at 192 °C, the supercooled liquid could be handled as a solid up to 280 °C owing to its high viscosity. The glass and its melt exhibited proton conduction with a proton transport number of ∼1. Although covalent O−H bonds were weakened by relatively strong hydrogen bonding, the proton conductivity (4×10−4 S cm−1 at 276 °C) was considerably lower than that of phosphoric acid. The high viscosity of the melt was due to the tight cross-linking of phosphate ion chains by six-fold-coordinated Si atoms. The low proton conductivity was attributed to the trapping of positively charged proton carriers around anionic SiO6 units (expressed as (SiO6/2)2−) to compensate for the negative charges. 相似文献
94.
Yasutaka Ishii Toshimitsu Noda Masakazu Kawahara Masaya Ogawa 《Magnetic resonance in chemistry : MRC》1984,22(7):416-418
The 13C NMR spectra of tricyclo[4.2.1.02,5]nonanes and tetracyclo[5.4.1.02,6.08,11]dodecanes and their dimethyl derivatives were measured to demonstrate the four-membered ring annelation effects on the bicyclo[2.2.1]heptane skeleton, and the steric δ-syn effects of the methyl groups attached to the four-membered ring on the bridge carbons in these systems. 相似文献
95.
Dong-Feng Gu Alex M. Jamieson Myong-Soo Lee Masaya Kawasumi Virgil Percec 《Liquid crystals》1992,12(6):961-971
The light scattering technique was used to investigate the viscoelastic parameters characterizing director twist distortions in miscible nematic mixtures of 5CB (pentacyanobiphenyl) with two side chain liquid crystal polymers and a main chain liquid crystal polymer. By applying an AC electric field to homeotropically-aligned nematic monodomains of the mixtures, the field-dependent scattering intensities and director orientation fluctuation relaxation rates yield, respectively, the twist elastic constant K22 and viscosity coefficient γ1. The results directly demonstrate that the addition of liquid crystal polymers causes substantial decreases of the relaxation rates for dynamic light scattering from the twist mode and these changes are due to small decreases in K22 coupled with large increases in γ1. The decrements in K22 are comparable for both side chain and main chain liquid crystal polymers. The relative increase in the twist viscosity for the side chain liquid crystal polymers is much smaller than those of main chain polymers. A theoretical model is used to qualitatively interpret the difference between the viscous behaviour of the twist mode for both side chain and main chain liquid crystal polymers in a nematic solvent. 相似文献
96.
Masaya Nagai Hiroyuki Yada Takashi Arikawa Koichiro Tanaka 《International Journal of Infrared and Millimeter Waves》2006,27(4):505-515
We demonstrate time-domain attenuated total reflection spectroscopy in terahertz frequency region. Geometry of the reflection
measurement is well optimized to obtain accurate optical constants of water or aqueous biomolecular system. We determine the
dielectric constants of distilled water and sucrose solutions with this technique. This technique will open new aspects in
the research field of biological systems in water. 相似文献
97.
Isao Akiyama Masaya Ogawa Keiichi Takase Toshiyuki Takamuku Toshio Yamaguchi Norikazu Ohtori 《Journal of solution chemistry》2004,33(6-7):797-809
Molecular dynamics (MD) simulations and X-ray scattering experiments have been carried out on liquid 1-propanol. The radial distribution functions obtained from these two methods were in good agreement with each other. On the basis of the hydrogen-bond number and the angular correlation functions of the four sequentially hydrogen-bonded O atoms derived from the MD calculation, it was found that the hydrogen-bonded O atoms preferentially form a planar zigzag chain structure, but that the plane undulates like a wave. 相似文献
98.
Toray's ionic-type photosensitive polyimide, “Photoneece”, is widely used as an interdielectric and as a protection layer for microelectronics, because of its properties, such as the removal of photoreactive groups at low temperature, excellent thermal, mechanical and electrical film properties and excellent adhesion to various substrates. Toray has developed a new type of “Photoneece”, UR-5100, which is a low-stress photosensitive polyimide. In addition to a low thermal expansion coefficient (25 ppm/°C), “Photoneece” UR-5100 also features high resolution with an aspect ratio of more than 2.0 in 40 μm imaged film, and excellent mechanical properties in the cured film such as high elongation (>20%) and tensile strength (>200 MPa), even after 60 hr heat treatment at 350°C. “Photoneece” UR-5100 can be applied in multichip modules (MCMs), hybrid circuits, ICs and LSIs. In this paper the characterization and processing of this “Photoneece” UR-5100 are described. 相似文献
99.
Takahiro Uno Masaya Minari Masataka Kubo Takahito Itoh 《Journal of polymer science. Part A, Polymer chemistry》2004,42(18):4548-4555
Asymmetric anionic polymerizations of 2,6-dimethyl-7-phenyl-1,4-benzoquinone methide ( 1 ) were performed with various chiral anionic initiators, and the specific rotations of the obtained polymers were investigated. Optically active poly( 1 )s with configurational chirality were obtained with all the initiators, and a complex of fluorenyllithium (FlLi) with (−)-sparteine [(−)-Sp] produced poly( 1 ) with the largest negative specific rotation ([α]435 = −26.8°). The specific rotations of poly( 1 )s obtained with FlLi/(−)-Sp depended on the initiator concentration and the solvent polarity. The maximum specific rotations were obtained at an almost constant initiator concentration (ca. 0.03 mol/L), regardless of the monomer concentration, in toluene, whereas a higher initiator concentration was required in more polar solvents. These results suggested that the aggregation state of the propagating chain end significantly affected the specific rotation of poly( 1 ). © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4548–4555, 2004 相似文献
100.
Akira Higashibata Mari Imamizo-Sato Masaya Seki Takashi Yamazaki Noriaki Ishioka 《BMC biochemistry》2006,7(1):19-9