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31.
Y. Akiyama F. Mizukami H. Izutsu M. Sato K. Maeda Y. Kiyozumi K. Sakaguchi 《Journal of Sol-Gel Science and Technology》1998,13(1-3):421-425
A novel organic-inorganic composite was prepared by a sol-gel process using hydrolysis and condensation of tetraethoxysilane (TEOS) reacted with a saccharide. During the process, ethoxy groups of the TEOS were replaced with hydroxyl groups of the saccharide and, consequently, saccharide molecules were combined with silica through their hydroxyl groups. Samples obtained under different reaction conditions were used for optical resolution of a metal chelate compound. The resolution ability of the composites was affected by the amount of water added for hydrolysis and of the saccharide. In particular, the amount of water drastically influenced the optical resolution performance. Composites obtained at the lower H2O/TEOS ratio gave the metal chelate compound a higher optical rotation. Three types of composites with the same composition were prepared by kneading, impregnation and by the sol-gel method, and were compared. The sol-gel composite showed the best optical resolution ability. It was concluded that the optical resolution ability was closely related to dispersibility of saccharide in the silica matrix. 相似文献
32.
33.
Beker H Boggild H Boissevain J Cherney M Dodd J Esumi S Fabjan CW Fields DE Franz A Hansen KH Holzer EB Humanic TJ Jacak BV Jayanti R Kalechofsky H Kobayashi T Kvatadze R Lee YY Leltchouk M Lörstad B Maeda N Medvedev A Miake Y Miyabayashi A Murray M Nagamiya S Nishimura S Noteboom E Pandey SU Piuz F Polychronakos V Potekhin M Poulard G Sakaguchi A Sarabura M Shigaki K Simon-Gillo J Sondheim W Sugitate T Sullivan JP Sumi Y van Hecke H Willis WJ Wolf K Xu N 《Physical review letters》1995,74(17):3340-3343
34.
W. K. A. Kumuduni Y. Nakata T. Okada M. Maeda 《Applied physics. B, Lasers and optics》1994,58(4):289-294
One-dimensional imaging laser-induced fluorescence spectroscopy has been used for in-situ measurements of spatial distributions of YO molecules produced during the ArF-laser ablation of YBa2 Cu3 O
7–x
in vacuum and oxygen gas environment. The time-integrated angular distribution of particles ejected in vacuum has a cos
n
form, where 11 <n < 13. When oxygen gas was introduced, YO molecules were confined in a smaller volume, and temporal changes of their spatial distribution were interpreted in terms of blast-wave formation. 相似文献
35.
Espy MA Dehnhard D Edwards CM Palarczyk M Langenbrunner JL Davis B Burleson GR Blanchard S Gibbs WR Lail B Nelson B Park BK Zhao Q Cummings WJ Delheij PP Jennings BK Henderson R Häusser O Thiessen D Brash E Jones MK Larson B Brinkmöller B Maeda K Morris CL O'Donnell JM Penttilä S Swenson D Tupa D Bennhold C Kamalov SS 《Physical review letters》1996,76(20):3667-3670
36.
37.
Viscous properties of partially hemolyzed erythrocyte suspensions were studied with a cone-plate viscometer. A Casson plot was successfully applied for analysis of the viscous properties. When the degree of hemolysis was increased, Casson viscosity (
c) of the partially hemolyzed erythrocyte suspensions increased, but the substitution of hemoglobin solution with the same O2-carrying capacity of hemolyzed fraction (containing ghost) reduced the
c remarkably. The yield stress (f
c) of the intact erythrocyte suspension increased with increasing hematocrit, but thef
c of partially hemolyzed erythrocyte suspension was dependent on both hematocrit and the degree of hemolysis. The apparent viscosity (
a) of erythrocyte suspension was drastically increased with the slight hemolysis, and became maximum at a certain degree of hemolysis which was dependent on both total hemoglobin concentration and shear rate. Such influence of hemolysis on the
a was also evident in the mixture of erythrocyte suspension and hemoglobin solution. These results suggest that the hemoglobin molecule plays a certain role in erythrocyte-erythrocyte interaction in their suspension, which modifies the viscosity. 相似文献
38.
39.
Cao B Wakahara T Tsuchiya T Kondo M Maeda Y Aminur Rahman GM Akasaka T Kobayashi K Nagase S Yamamoto K 《Journal of the American Chemical Society》2004,126(30):9164-9165
A new metallofullerene, La2@C78, has been synthesized by DC arc discharge method, isolated by high-performance liquid chromatography, and characterized by laser desorption time-of-flight mass spectrometry, UV-vis-NIR absorption, differential pulse voltammetry, 13C NMR spectroscopy, and theoretical calculations. The La2@C78/CS2 solution is dark violet and presents several characteristic absorption features at 647, 561, 533, and 386 nm, with an onset around 1000 nm. With respect to empty D3-C78, the capability of La2@C78 as an electron acceptor or donor is stronger. Addition of 1,1,2,2-tetrakis(2,4,6-trimethylphenyl)-1,2-disirane to La2@C78 photochemically, as well as thermally, affords bis- and mono-adducts. Theoretical studies and 13C NMR spectroscopic analysis of La2@C78 indicate that it possesses a D3h-C78 cage (78:5). 相似文献
40.
Sinomenine, an alkaloid of the Japanese plant Sinomenium acutum, was converted to the 4-phenylether by the Ullmann reaction in a good yield. The Clemmensen reduction of sinomenine-phenylether and of its derivatives gave (+)-3-methoxy-4-phenoxy-N-methyl-Δx-morphinan.
Hydrogenation and successive sodium-liquid ammonia reduction of (+)-3-methoxy-4-phenoxy-N-methyl-Δx-morphinan gave (+)-3-methoxy-N-methylmorphinan. 相似文献