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1.
Yamashita Hiromi Ariyuki Masao Yoshizawa Katsuhiro Kida Keiko Ohshiro Satoshi Anpo Masakazu 《Research on Chemical Intermediates》2004,30(2):235-245
The photocatalytic reactivities of chromium-containing mesoporous silica molecular sieves (Cr-HMS) under visible light irradiation have been investigated. Cr-HMS involves tetrahedral chromium oxide (Cr-oxide) moieties which are highly dispersed and incorporated in the framework of molecular sieve with two terminal Cr=O groups. In the presence of propane with molecular oxygen, a partial oxidation proceeded under visible light irradiation to produce acetone and acrolein, with high selectivity, while a complete oxidation proceeded under UV light irradiation mainly to produce CO2. The charge-transfer excited state of the tetrahedral Cr-oxide moieties plays a significant role in the photocatalytic reactions. 相似文献
2.
Masato Matsugi Masakazu Hasegawa Sachina Okamoto Yoshimi Ikeya Yuji Mori 《Tetrahedron letters》2007,48(23):4147-4150
A modified light-fluorous Mukaiyama reagent bearing a C8F17 tag was prepared and examined in ester and amide forming condensation reactions. Following the reactions, the desired product was effectively separated from the fluorous pyridone by-product using a simple fluorous solid phase extraction. 相似文献
3.
Masakazu Muramatsu 《Mathematical Programming》1998,83(1-3):393-406
In this paper, we introduce an affine scaling algorithm for semidefinite programming (SDP), and give an example of a semidefinite
program such that the affine scaling algorithm converges to a non-optimal point. Both our program and its dual have interior
feasible solutions and unique optimal solutions which satisfy strict complementarity, and they are non-degenerate everywhere. 相似文献
4.
The Heat Kernel on Hyperbolic Space 总被引:1,自引:0,他引:1
The purpose of this note is to provide a new proof for the explicitformulas of the heat kernel on hyperbolic space. By definition,the hyperbolic space Hn is a (unique) simply connected completen-dimensional Riemannian manifold with a constant negative sectionalcurvature 1. 1991 Mathematics Subject Classification58G32, 58G11. 相似文献
5.
Hiroki Higuchi Hidetoshi Kawai Masakazu Ohkita Takanori Suzuki 《Tetrahedron letters》2004,45(15):3027-3030
The newly prepared tetracyanoanthraquinodimethane (TCNAQ) derivatives 1a,b with a chiral auxiliary are good electron acceptors and exhibit weak circular dichroism (CD) based on the absorption of TCNAQ. The twin-type electron acceptor 1c with two TCNAQ units shows larger ellipticity by exciton coupling. UV-vis, CD, and fluorescence spectra were changed drastically upon electrochemical reduction of 1c, which demonstrates the unprecedented three-way-output response system. 相似文献
6.
Preparation and characterization of nitrogen-doped TiO2 photocatalyst in different acid environments
Ye Cong Ling Xiao Jinlong Zhang Feng Chen Masakazu Anpo 《Research on Chemical Intermediates》2006,32(8):717-724
Nitrogen-doped TiO2 powders were successfully prepared by a wet method, i.e., a micro-emulsion-hydrothermal method, in different acid environments.
Several characterization techniques, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-visible diffuse
reflectance spectra, were combined to determine the crystal phase, concentration and chemical states of the nitrogen doped
in TiO2. The high photocatalytic activity of the nitrogen-doped TiO2 was evaluated through the decomposition of rhodanmine B under visible light irradiation. It was suggested that the doped
nitrogen formed oxynitride (NO) and produced impurity states at higher above the valence band of TiO2. Therefore, the nitrogen doping could enhance the response of photocatalyst to the visible light and improve the photocatalytic
activity because of the narrowing of band gap of TiO2. 相似文献
7.
Toshio Ogawa Masakazu Sakai Wataru Ishitobi 《Journal of polymer science. Part A, Polymer chemistry》1986,24(1):109-118
Molecular weight distribution of Nylon 12 was determined with hexafluoroisopropanol/toluene mixture as eluent by gel permeation chromatography. Calibration curve for Nylon 12 was easily obtained from that of polystyrene because the method of universal calibration was applicable among these polymers. The molecular weight distributions of Nylon 12 were always broader than expected by the theory of polymerization, i.e., most probable distribution. This result was not caused by broadening effect in gel permeation chromatography, but by polymerization itself. 相似文献
8.
The formation constants of the mono-adducts of α-acylcamphorato-copper(II) chelates such as (+)-Cu(facam)2, (?)-Cu(facam)2, (+)-Cu(hfbc)2 and (?)-Cu(hfbc)2 with some chiral Lewis bases were determined spectrophotometrically in benzene. In order to compare the adduct formation constants obtained with the (+)- and (?)-forms, some pairs of chiral Lewis bases such as 1-amino-2-propanol [(R)(?), (S)(+)], 1-(α-naphthyl)ethylamine [(R)(+), (S)(?)], α-phenyl ethylamine [(R)(+), (S)(?)] and also quinine and quinidine were examined as neutral ligands. Although not very pronounced, the effects of combinations obtained for (+)- or (?)-Cu(II) chelates and (+)- or (?)-ligands indicate that formation constants obtained by the formation of adducts with the ligands having different directions of the optical rotation seems to be superior to those with the same direction. 相似文献
9.
Jingye Li Kohei Sato Saneto Asano Minoru Iida Yoneho Tabata Masakazu Washio 《European Polymer Journal》2005,41(3):547-555
Crosslinked and non-crosslinked polytetrafluoroethylene films (RX-PTFE and V-PTFE films, respectively) were irradiated by γ-ray and then grafted with styrene in liquid phase. Microscope FT-IR spectroscopy, TGA, solid state 13C CP/MAS and high resolution HS/MAS NMR spectroscopy, wide-angle X-ray diffraction (WAXD) study were used to get the structural information of the styrene grafted RX-PTFE and V-PTFE films. From microscope FT-IR spectra of the grafted RX-PTFE films, the “grafting front mechanism” was proved. TGA analysis showed that the grafted films have a small degradation step and two main degradation steps. In the 13C CP/MAS NMR spectra of the non-grafted films, there are no signal due to the absence of the hydrogen atom. While in the spectra of the grafted films, there are signals attributed to the polystyrene grafts. In the 13C HS/MAS NMR spectra of the grafted films, the relative intensity of the peaks attributed to the polystyrene grafts increased while the relative intensity of the peak attributed to PTFE matrix decreased with the increase in the DOG. From WAXD patterns, the intensity of the crystalline peak decrease with the increase in the DOG. The grafted films were sulfonated by chlorosulfonic acid and the results of highest IEC value exceeded 3.0. Those results will be reported in the near future. 相似文献
10.
Jingye Li Fumihiro Muto Akihiro Oshima Masakazu Washio Shigetoshi Ikeda Yoneho Tabata Chihiro Matsuura 《European Polymer Journal》2006,42(6):1222-1228
New proton exchange membranes (PEMs) were prepared by pre-irradiation induced grafting of α-methylstyrene (AMS)/styrene (STY)/divinylbenzene (DVB) into the crosslinked polytetrafluoroethylene (RX-PTFE) films and successively sulfonated. The new PEMs showed the improved glass transition temperature and chemical stability as compared with the PEMs prepared by pre-irradiation induced grafting of STY/DVB. The balance of the cost, grafting kinetic, thermal properties and the properties of the resulted proton exchange membrane is the key point of this work. 相似文献