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101.
Naoko Asakuma Hiroshi Hirashima Hiroaki Imai Toshimi Fukui Motoyuki Toki 《Journal of Sol-Gel Science and Technology》2003,26(1-3):181-184
Structural changes in sol-gel films with photo-irradiation were investigated using zinc oxide (ZnO) derived from zinc acetate. The exposure of the films to an ultraviolet lamp induced hexagonal ZnO crystals in a relatively dense amorphous structure. On the other hand, the formation of zinc metal was found in a porous gel film. The photo-induced crystallization and reduction are ascribed to the electronic excitation in the metastable non-crystalline states. 相似文献
102.
T Ohmori K Tamura K Fukui G Kawanishi M Mitsuyama K Nomoto T Miyazaki 《Chemical & pharmaceutical bulletin》1989,37(4):1019-1022
A galactosaminoglycan moiety was obtained from an antitumor polysaccharide fraction (SN-C) isolated from Cordyceps ophioglossoides culture. SN-C was subjected to sonication, then a protein-bound galactosaminoglycan (CO-N) was isolated specifically by precipitation with 10% ammonium hydroxide. When given intraperitoneally to mice, CO-N inhibited the proliferation of sarcoma 180 cells inoculated into the peritoneal cavity and exhibited a marked life-prolonging effect against ascitic tumors such as Ehrlich carcinoma and IMC carcinoma. CO-N also showed an inhibitory effect against solid Ehrlich carcinoma when given intratumorally and significantly inhibited the growth of a syngeneic solid tumor (MM46 mammary carcinoma) upon intravenous administration at a low dose. CO-N showed a cytocidal effect against cultured cells of IMC and P388D1 in vitro. Flow cytometric analysis demonstrated that fluorescein isothiocyanate-CO-N binds to the surface of Ehrlich cells. 相似文献
103.
Y. Ohtsu H. Fukui T. Kanda K. Nakamura M. Nakano O. Nakata Y. Fujiyama 《Chromatographia》1987,24(1):380-384
Summary Silicone polymer-coated silica gels modified with octadecyl and octyl groups (S/S-C18, S/S-C8), or “capsule-type silica gels” were developed as packing materials for reversed-phase liquid chromatography. They were obtained
by coating the surface of totally porous silica gel with a homogeneous silicone polymer film, and thereafter modifying the
coating polymer with octadecyl or octyl groups. Retaining the advantages of silica-based packings, they show strong resistance
of alkali-like organic porous polymeric materials. 相似文献
104.
Minimum principles of chemical reaction coordinates are established. IRC (intrinsic reaction coordinate) draws the path of minimum distance from reactant to product. The distance is measured in the rigged configuration Riemannian space whose metric is determined by the distribution of the adiabatic potential energy. Moreover, minimum property of the intrinsic principle of least action is established for the intrinsic dynamism of chemical reaction. Minimum principle of the path connecting intercell boundary with cell is also discussed. 相似文献
105.
Differential geometry of chemically reacting systems 总被引:1,自引:0,他引:1
This paper is a detailed differential geometrical study of chemically reacting systems. In particular the following coordinate-free properties of chemically reacting systems are obtained: 1) the general solution of the intrinsic reaction coordinate (IRC) (henceforth referred to as meta-IRC), 2) extended definitions of the Hessian matrix and normal vibrations at any non-equilibrium point on the surface, and 3) clarification of the close connection between the geometry of meta-IRC and the geography of the surface at a transition point. The theory is elucidated using a model potential surface. 相似文献
106.
Abe F Amidei D Apollinari G Atac M Auchincloss P Baden AR Bamberger A Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge JP Bertolucci S Bhadra S Binkley M Blair R Blocker C Booth AW Brandenburg G Brown D Buckley E Byon A Byrum KL Campagnari C Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chiarelli G Chinowsky W Cihangir S Clark AG Connor D Contreras M Cooper J Cordelli M Crane D Curatolo M 《Physical review D: Particles and fields》1991,43(3):664-686
107.
Abe K Amako K Arai Y Asano Y Chiba M Chiba Y Daigo M Emura T Endo I Fukawa M Fukui T Fukushima Y Haba J Haidt D Hayashibara I Hemmi Y Higuchi M Hirose T Hojyo Y Homma Y Hoshi Y Ikegami Y Ishihara N Kamitani T Kanematsu N Kanzaki J Kikuchi R Kondo T Koseki T Kubo K Kurashige H Matsui T Minami M Miyake K Mori S Nagashima Y Nakamura T Nakano I Odaka S Ogawa K Ohama T Ohsugi T Ono A Osabe H Saito H Sakae H Sakamoto H Sakamoto S Sakano M Sakuda M Sasao N Sato M Shioden M Shirai J Suekane F 《Physical review letters》1988,61(8):915-918
108.
Singly and Doubly 1,2‐Phenylene‐Inserted Porphyrin Arch‐Tape Dimers: Synthesis and Highly Contorted Structures
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Norihito Fukui Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2018,57(21):6304-6308
Singly and doubly 1,2‐phenylene‐inserted NiII porphyrin arch‐tape dimers 3 and 9 were synthesized from the corresponding β‐to‐β 1,2‐phenylene‐bridged NiII porphyrin dimers 5 and 11 via Ni0‐mediated reductive cyclization and DDQ/Sc(OTf)3‐promoted oxidative cyclization as key steps, respectively. Owing to the fused eight‐membered ring(s), 3 showed a more contorted structure than those of previously reported arch‐tape dimers 2 a and 2 b possessing a fused seven‐membered ring. Furthermore, 9 displayed much larger molecular contortion. As the molecular contortion increases, the Q band of the absorption spectrum becomes more red‐shifted and the electrochemcial HOMO–LUMO gap becomes smaller, reaching at 1294 nm and 0.77 eV in 9 , respectively. The effect of molecular contortion on the electronic properties was studied by means of DFT calculations. 相似文献
109.
Bimetallic Ag‐Pt Sub‐nanometer Supported Clusters as Highly Efficient and Robust Oxidation Catalysts
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Dr. Fabio R. Negreiros Dr. Avik Halder Dr. Chunrong Yin Dr. Akansha Singh Dr. Giovanni Barcaro Dr. Luca Sementa Dr. Eric C. Tyo Dr. Michael J. Pellin Dr. Stephan Bartling Dr. Karl‐Heinz Meiwes‐Broer Dr. Sönke Seifert Dr. Prasenjit Sen Dr. Sandeep Nigam Dr. Chiranjib Majumder Dr. Nobuyuki Fukui Dr. Hisato Yasumatsu Dr. Stefan Vajda Dr. Alessandro Fortunelli 《Angewandte Chemie (International ed. in English)》2018,57(5):1209-1213
A combined experimental and theoretical investigation of Ag‐Pt sub‐nanometer clusters as heterogeneous catalysts in the CO→CO2 reaction (COox) is presented. Ag9Pt2 and Ag9Pt3 clusters are size‐selected in the gas phase, deposited on an ultrathin amorphous alumina support, and tested as catalysts experimentally under realistic conditions and by first‐principles simulations at realistic coverage. In situ GISAXS/TPRx demonstrates that the clusters do not sinter or deactivate even after prolonged exposure to reactants at high temperature, and present comparable, extremely high COox catalytic efficiency. Such high activity and stability are ascribed to a synergic role of Ag and Pt in ultranano‐aggregates, in which Pt anchors the clusters to the support and binds and activates two CO molecules, while Ag binds and activates O2, and Ag/Pt surface proximity disfavors poisoning by CO or oxidized species. 相似文献
110.
Hisayoshi Kobayashi Satohiro Yoshida Kenichi Fukui Kimio Tarama Hiroshi Kato 《Chemical physics letters》1978,53(3):457-461
The periodic model of finite surfaces has been employed to investigate the localizability of the chemisorption interaction and to examine the validity of the cluster model. The adsorbate—surface interaction is estimated by the usual perturbation method. The model is applied to chemisorption of hydrogen molecule on a Ni(100) surface. As for the present calculations, the period model is shown to be advantageous over the cluster model in representing both the adsorbate-free surface state and the adsorbate—surface interaction. 相似文献