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1.
In this note we give presentations, up to conjugacy, of all finite subgroups of the mapping class group of a closed surface of genus 2, using the Humphries generators. An application to homology representations is given. 相似文献
2.
We give a unified method to obtain the conservativeness of a class of Markov processes associated with lower bounded semi-Dirichlet forms on L 2(X;m), including symmetric diffusion processes, some non-symmetric diffusion processes and jump type Markov processes on X, where X is a locally compact separable metric space and m is a positive Radon measure on X with full topological support. Using the method, we give an example in each section, providing the conservativeness of the processes, that are given by the “increasingness of the volume of some sets(balls)” and “that of the coefficients on the sets” of the Markov processes. 相似文献
3.
N-Aryl-protecting groups were introduced in glucosamines to achieve β-selective glycosylation. Various N-aryl aminosugars were synthesized via Buchwald–Hartwig reaction. Glycosylation using glycosyl trichloroacetimidates of N-aryl aminosugars smoothly proceeded in the presence of trimethylsilyl trifluoromethanesulfonate. Use of a glycosyl donor comprising an electron-donating 2,4-dimethoxyphenyl (DMP) group led to the glycosylation proceeding with high β selectivity. This stereoselectivity seemed to be derived from the formation of an aziridine intermediate. The DMP-protecting group can be removed immediately by using ammonium hexanitratocerate (IV). 相似文献
4.
Nakayama Masanobu Nishimura Norimitsu Kondo Yuki Takeda Hayami Kasuga Toshihiro 《Journal of Solid State Electrochemistry》2017,21(4):1137-1143
Journal of Solid State Electrochemistry - We demonstrate the Laplace transform (LT) impedance technique for measuring electrochemical lithiation and delithiation in the two-phase system of spinel... 相似文献
5.
Circular autocorrelation of stationary circular Markov processes 总被引:1,自引:0,他引:1
Toshihiro Abe Hiroaki Ogata Takayuki Shiohama Hiroyuki Taniai 《Statistical Inference for Stochastic Processes》2017,20(3):275-290
The stationary Markov process is considered and its circular autocorrelation function is investigated. More specifically, the transition density of the stationary Markov circular process is defined by two circular distributions, and we elucidate the structure of the circular autocorrelation when one of these distributions is uniform and the other is arbitrary. The asymptotic properties of the natural estimator of the circular autocorrelation function are derived. Furthermore, we consider the bivariate process of trigonometric functions and provide the explicit form of its spectral density matrix. The validity of the model was assessed by applying it to a series of wind direction data. 相似文献
6.
Suenaga Yuma Kawano Hiroaki Takamatsu Toshihiro Matsumura Yuriko Ito Norihiko Iwasawa Atsuo Okino Akitoshi 《Plasma Chemistry and Plasma Processing》2022,42(3):575-586
Plasma Chemistry and Plasma Processing - Atmospheric low-temperature plasma has received attention for application in disinfection methods. In this study, we develop a plasma bubbling method as a... 相似文献
7.
Spatio-temporal velocity fields of an axisymmetric sudden expansion were measured using an ultrasonic velocity profiler and analyzed to investigate the transitional scheme of the spatial structure using two-dimensional Fourier transform and proper orthogonal decomposition techniques. The variation of the zero-crossing point, the fluctuation energy directed upstream and the eigenmode spectrum all have the same transitional scheme as a function of the Reynolds number. The transitional scheme can be classified Re d<1,000 for the laminar regime, Re d=1,000–3,000 for the transitional regime and Re d>3,000 for the turbulent regime. Especially, in the transitional regime, we found large changes in the flow structure at Re d=1,500 and 2,000. The jump at Re d=2,000 is caused by the change in the flow condition upstream. The jump at Re d=1,500 clearly shows a change in the spatial structure of the flow. 相似文献
8.
Kazukiyo Kobayashi Hiroshi Sumitomo Akira Kobayashi Toshihiro Akaike 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5-7):655-667
Polystyrene derivatives with lactose, glucose, maltose, maltotriose, maltopentaose, and maltoheptaose on each benzene ring were prepared by the radical polymerization of a new class of macromers synthesized by coupling the corresponding oligosaccharide lactones with p-vinylbenzylamine. These polymers consisting of amphiphilic structural units were water-soluble, and organic solutes were bound to hydrophobic microenvironments of the polymers in water. α-D-Glucopyranose-carrying polymers were recognized and precipitated by concanavalin A. Cultivation of liver cells (hepatocytes) was attempted using culture dishes whose surface was coated with lactose-, glucose-, maltose-, and maltotriose-carrying polystyrenes. It has been found that a lactose-carrying polystyrene (PVLA) is a useful surface material for hepatocyte culture. 1) Highly specific adhesion of hepatocytes was attained for PVLA-coated dishes with or without serum supplement. 2) The cell adhesion was a threshold phenomenon with respect to the PVLA concentration on the dish. 3) The cell adhesion was effectively inhibited when hepatocytes were treated with PVLA molecules in the medium prior to culture. 4) The adhesion was not inhibited by albumin, an adhesion-inhibitory protein in serum. These findings suggest that pendent galactose residues of a PLVA molecule functioned as a strong recognition determinant for hepatocytes. We assume that multi-antennary, high-density galactose residues of PVLA are attributed to the specific adhesion of hepatocytes. 相似文献
9.
10.
Toshihiro Kasezawa Hideyoshi Horimai Hiroshi Tabuchi Tsutomu Shimura 《Optical Review》2016,23(6):997-1003
A new photovoltaic generation unit based on the application of holographic technologies called a Holo-Window is proposed in this work. The basic principle and the optical configuration used for the basic experimental unit are described. Suitable fabrication technology for a hologram with the broadband spectrum required to provide the appropriate sunlight capture capability is then discussed. Finally, a laboratory-prototype Holo-Window unit was developed and its performance was evaluated. 相似文献