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121.
122.
Bunichiro Yamada Masaki Itahashi Takayuki Otsu 《Journal of polymer science. Part A, Polymer chemistry》1978,16(7):1719-1733
To obtain the optimum values of the monomer reactivity ratios for the copolymerization systems with largely different reactivities between both monomers, a nonlinear least-squares procedure which took into account the weights of experimental data, was proposed and discussed. The weights of the data were treated for the errors arisen from the amounts of monomers charged, the densities of monomers, the weights of copolymer formed, and the composition of copolymer. The least-squares procedure with the consideration of the weights was applicable to both differentiated equation and integrated equation derived by Lewis and Mayo. This procedure was applied to radical copolymerizations of α-substituted crotonic esters with styrene, and reasonable monomer reactivity ratios were obtained. It was noted that errors from the copolymer composition were more important than those from the other factors and that the use of the integrated equation was recommended even when the copolymers were isolated at low conversions. 相似文献
123.
124.
Terao K Ohsawa A Mori Y Narita T Ichikawa K Dobashi T 《Colloids and surfaces. B, Biointerfaces》2004,37(3-4):129-132
Microcapsules having polyethyleneglycol-grafted poly(ureaurethane) (PUU) membrane and di-2ethylhexyl phthalate core have been prepared, and the structure when they were suspended in dispersing ethanol have been studied by means of single-particle light scattering method. The PUU membrane was synthesized from monomers with aromatic functional groups (microcapsule MC110) and hexamethylene functional groups (microcapsule MC160). Because the outer and inner solvent passed through the membrane easily, the outside and inside of the membrane were the same at the equilibrium state. The thickness of the wall membrane was significantly smaller than that calculated from the overall weight ratio of the wall-forming material and the core solvents. It was attributed to low affinity of PUU membranes and ethanol. 相似文献
125.
Takayuki?FurutaEmail author Jung?Il Bong Lambert?Alan 《Integral Equations and Operator Theory》2004,48(2):137-146
In this note we examine the relationships between p-hyponormal
operators and the operator inequality
. This leads to a method for
generating examples of p-hyponormal operators which are not q-hyponormal
for any
. Our methods are also shown to have implications for the class
of Furuta type inequalities. 相似文献
126.
We demonstrate that molecules with a moderate permanent dipole moment can be oriented with combined electrostatic and pulsed, nonresonant laser fields. We use OCS molecules as a sample. The degree of orientation can be increased by increasing the magnitude of electrostatic field and the peak intensity of the laser field or by decreasing the rotational temperature of the molecules. 相似文献
127.
We studied the antiphase self-pulsation in a globally coupled three-mode laser operating in different optical spectrum configurations. We observed locking of modal pulsation frequencies, quasiperiodicity, clustering behaviors, and chaos, resulting from the nonlinear interaction among modes. The robustness of [p:q:r] three-frequency locking states and quasiperiodic oscillations against residual noise has been examined by using joint time-frequency analysis of long-term experimental time series. Two sharply antithetical types of switching behaviors among different dynamic states were observed during temporal evolutions; noise-driven switching and self-induced switching, which manifests itself in chaotic itinerancy. The modal interplay behind observed behaviors was studied by using the statistical dynamic quantity of the information circulation. Well-organized information flows among modes, which correspond to the number of degeneracies of modal pulsation frequencies, were found to be established in accordance with the inherent antiphase dynamics. Observed locking behaviors, quasiperiodic motions, and chaotic itinerancy were reproduced by numerical simulation of the model equations. 相似文献
128.
Hidefumi Ohsugi Takayuki Hibi 《Proceedings of the American Mathematical Society》2001,129(9):2541-2546
A compressed polytope is an integral convex polytope any of whose reverse lexicographic initial ideals is squarefree. A sufficient condition for a -polytope to be compressed will be presented. One of its immediate consequences is that the class of compressed -polytopes includes (i) hypersimplices, (ii) order polytopes of finite partially ordered sets, and (iii) stable polytopes of perfect graphs.
129.
Yasutaka Takahashi Ayako Ohsugi Takeshi Arafuka Tomokazu Ohya Takayuki Ban Yutaka Ohya 《Journal of Sol-Gel Science and Technology》2000,17(3):227-238
The effects of several hydroxyketones such as acetol, actoin, -ketobutanol themselves and their combinations with monoethanolamine (MEA) or ethylenediamine (ED) on the stabilization of titanium tetraisopropoxide (TTIP) in isopropanol solution are examined. Acetoin itself and the imine derivatives of acetol and acetoin were found to show extraordinarily strong stabilizing effect for the alkoxide. The properties including the crystal modifications and refractive index of TiO2 films that were dip-coated using each stabilized solution are examined and discussed in comparison with those of the films obtained from the diethanolamine (DEA) systems. The effect of UV-light irradiation to the gel films on the crystallization of TiO2 is also examined and discussed. 相似文献
130.
By using the historical data from the Japanese banks’ database at “The Bankers Library” of Japanese Banker Association, we analyze the historical network of banks from 1868 to 2006. Firstly, we define a bank every year by a particle and draw a space-time evolution process of merger, division, establishment, and failure by a tree diagram structure. We found that the distribution of the tree basin size of real data and simulation result are mostly fitting well. Secondly, we analyze the raw data of financial statements of banks collected by the National Diet library. We confirm that the distributions of the amount of deposits have fat-tail every year, however, small deviations are observed relating to governmental policy. 相似文献