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排序方式: 共有229条查询结果,搜索用时 296 毫秒
91.
92.
Naoki Osada 《Numerical Algorithms》1992,3(1):335-344
A fixed point sequence is singular if the Jacobian matrix at the limit has 1 as an eigenvalue. The asymptotic behaviour of some singular fixed point sequences in one dimension are extended toN dimensions. Three algorithms extrapolating singular fixed point sequences inN dimensions are given. Using numerical examples three algorithms are tested and compared. 相似文献
93.
94.
Mitsuyuki Shizuya Yuji Baba Takuro Nagai Minoru Osada Kosuke Kosuda Satoshi Takenouchi Yoshio Matsui Eiji Takayama-Muromachi 《Journal of solid state chemistry》2007,180(1):249-259
We synthesized a new cobalt oxide (CaOH)1.14CoO2 by utilizing a high-pressure technique. X-ray and electron diffraction studies revealed that the compound has a layered structure that consists of CdI2-type CoO2 layers and rock-salt-type double CaOH atomic layers. The two subcells have incommensurate periodicity along the a-axis, resulting in a misfit-layered structure. From resistivity and Seebeck coefficient measurements, we have shown that the two-dimensional (2-D) variable-range hopping (VRH) regime with hole conduction is dominant at low temperature for this compound. As temperature increases, the conduction mechanism undergoes crossover from the 2-D VRH regime to a thermal activation-energy-type regime. 相似文献
95.
Y. Osada 《Colloid and polymer science》1978,256(3):298
Ohne Zusammenfassung 相似文献
96.
Usui T Watanabe H Nakayama H Tada Y Kanoh N Kondoh M Asao T Takio K Watanabe H Nishikawa K Kitahara T Osada H 《Chemistry & biology》2004,11(6):799-806
Pironetin is a potent inhibitor of tubulin assembly and arrests cell cycle progression in M phase. Analyses of its structure-activity relationships suggested that pironetin covalently binds tubulin. To determine the binding site of pironetin, we synthesized biotinylated pironetin, which inhibited tubulin assembly both in vitro and in situ. The biotinylated pironetin selectively and covalently bound with tubulin. Partial digestion of biotinylated pironetin-treated tubulin by several proteases revealed that the binding site is the C-terminal portion of alpha-tubulin. By systematic alanine scanning, the pironetin binding site was determined to be Lys352 of alpha-tubulin. Lys352 is located at the entrance of a small pocket of alpha-tubulin, and this pocket faces the beta-tubulin of the next dimer. This is the first compound that covalently binds to the alpha subunit of tubulin and Lys352 of alpha-tubulin and inhibits the interaction of tubulin heterodimers. 相似文献
97.
98.
The cytochalasin class of fungal metabolites was analyzed by electrospray ionization tandem mass spectrometry (ESI-MS/MS) with the aim of developing a methodology for their rapid identification in microbial extracts. ESI-MS analyses of reference cytochalasins were performed and several product ions were produced in MS/MS experiments on parent ions that are structurally characteristic. A precursor ion search was performed to detect cytochalasins in an ethyl acetate extract of fungal strain RK97-F21. Three cytochalasins were detected and one of the components was identified as epoxycytochalasin H by comparing the tandem mass spectra of the product ions with those of reference compounds. This finding was further validated by LC/MS and LC/MS/MS experiments. 相似文献
99.
Hyuck Joon Kwon Kazuhiro Shikinaka Akira Kakugo Hidemitsu Furukawa Yoshihito Osada Jian Ping Gong 《高分子科学》2007,(1):47-55
F-actins are semi-flexible polyelectrolytes and can be assembled into large polymer-actin complex with polymorphism through electrostatic interaction with polycations. This study investigates the structural phase behavior and the growth of polymer-actin complexes in terms of its longitudinal and lateral sizes. Our results show that formation of polymer-actin complexes is cooperative, and morphology and growth of polymer-actin complexes depend on polycation species and concentrations of polycation and salt in a constant actin concentration. We found that the longitudinal growth and lateral growth of polymer-actin complexes are dominated by different factors. This induces the structural polymorphism of polymer-actin complexes. Major factors to influence the polymorphism of polymer-actin complexes in polyelectrolyte system have been discussed. Our results indicate that the semi-flexible polyelectrolyte nature of F-actins is important for controlling the morphology and growth of actin architectures in cell. 相似文献
100.
Liu Z Ma R Osada M Takada K Sasaki T 《Journal of the American Chemical Society》2005,127(40):13869-13874
We report on the controlled synthesis of single-crystal platelets of alpha- and beta-Co(OH)2 via homogeneous precipitation using hexamethylenetetramine as a hydrolysis agent. The alpha- and beta-Co(OH)2 hexagonal platelets of several micrometers in width and about 15 nm in thickness were reproducibly yielded in rather dilute CoCl2 solutions in the presence and absence of NaCl at 90 degrees C, respectively. The phase and size control of the products were achieved by varying both CoCl2 and NaCl concentrations. Polarized optical microscope observations revealed clear liquid crystallinity of colloidal suspensions of these high aspect-ratio platelets. The as-prepared alpha-Co(OH)2 containing interlayer chloride ions was intercalated with various inorganic or organic anions, keeping its high crystallinity and hexagonal platelike morphology. 相似文献