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131.
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
132.
Masakatsu Kasuya Tatsuo Taniguchi Ryuhei Motokawa Michinari Kohri Keiki Kishikawa Takayuki Nakahira 《Journal of polymer science. Part A, Polymer chemistry》2013,51(19):4042-4051
We developed a novel fluorescence labeling technique for quantification of surface densities of atom transfer radical polymerization (ATRP) initiators on polymer particles. The cationic P(St‐CPEM‐C4DMAEMA) and anionic P(St‐CPEM) polymer latex particles carrying ATRP‐initiating chlorine groups were prepared by emulsifier‐free emulsion polymerization of styrene (St), 2‐(2‐chloropropionyloxy)ethyl methacrylate (CPEM), and N‐n‐butyl‐N,N‐dimethyl‐N‐(2‐methacryloyloxy)ethylammonium bromide (C4DMAEMA). ATRP initiators on the surface of polymer particles were converted into azide groups by sodium azide, followed by fluorescent labeling with 5‐(N,N‐dimethylamino)‐N′‐(prop‐2‐yn‐1‐yl)naphthalene‐1‐sulfonamide (Dansyl‐alkyne) by copper‐catalyzed azide‐alkyne cycloaddition (CuAAC). The reaction time required for both azidation of ATRP‐initiating groups and successive fluorescence labeling of azide groups with Dansyl‐alkyne by CuAAC were investigated in detail by FTIR and fluorescence spectral measurement, respectively. The ATRP initiator densities on the cationic P(St‐CPEM‐C4DMAEMA) and anionic P(St‐CPEM) particle surfaces were estimated to be 0.21 and 0.15 molecules nm?2, respectively, which gave close agreement with values previously determined by a conductometric titration method. The fluorescence labeling through click chemistry proposed herein is a versatile technique to quantify the surface ATRP initiator density both on anionic and cationic polymer particles. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4042–4051 相似文献
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135.
Tsuneyuki Sato Tsuyoshi Yamamoto Tetsuo Ogawa Takayuki Otsu 《Journal of polymer science. Part A, Polymer chemistry》1986,24(7):1519-1528
Poly[acryloyl-L-valine (ALV)] microspheres containing peroxy ester groups were prepared by radical copolymerization of ALV with a small amount of di-tert-butyl peroxyfumarate. When the microspheres were irradiated in the presence of second vinyl monomers, long-lived propagating radicals of the second monomers were formed in the microspheres by the reaction of microsphere polymer radicals with the monomers. The presence of a minute quantity of ethyl alcohol served to soften the microspheres and made the polymer radicals more mobile in the microspheres. As a result, sharper ESR spectra of the propagating radicals were observed although their lifetimes became shorter. This microsphere method also yielded easily the stable propagating radicals of a-methylstyrene and 1,1-diphenylethylene which have no homopolymerizability in usual radical polymerization. When N-n-propyldimethacroylamide and N,N′-dimethyl-N,N′-dimethacroylhydrazine, which undergo cyclopolymerization, were used as second monomer, uncyclized polymer radicals were only observed. Some discussions were given on the propagation mechanism of the cyclopolymerization. 相似文献
136.
Masahiro Yoshida Tsutomu Matsui Yasuo Hatate Takayuki Takei Koichiro Shiomori Shiro Kiyoyama 《Journal of polymer science. Part A, Polymer chemistry》2008,46(5):1749-1757
Nylon‐polystyrene microcapsules with immobilized ferroelectric liquid crystalline segments were prepared, and permeability control of an encapsulated core material was investigated under an external electric field. A ferroelectric liquid crystal monomer possessing both mesogenicity and chirality responded effectively to the external electrical field. Permeation of the material (oxprenolol) contained in the inner aqueous core of the microcapsules was enhanced under a weak electric field (2 V). Furthermore, the permeability of oxprenolol did not depend on the external electric field in the absence of the ferroelectric liquid crystal segments. To clarify the controlled‐release mechanism of the core material, the light transmittance of the polymer membranes was quantitatively evaluated under an external electric field using a handmade polarized light transmittance apparatus. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1749–1757, 2008 相似文献
137.
Triarylboranes bearing two thiophene, dimethylthiophene, or benzothiophene units were synthesized. X-ray crystallographic analysis revealed the planar structure around the boron atom and non-bonding S-S interaction of the thiophene. They exhibited several intense absorption bands in the UV region. They were stable in the air for months and showed extremely strong Lewis acidities. 相似文献
138.
Nobuyuki Takeyasu Takayuki Deguchi Manami Tsutsumikawa Junichi Matsumoto Totaro Imasaka 《Analytical sciences》2002,18(3):243-246
A distributed-feedback dye laser with a quenching cavity was designed and constructed for generating a tunable picosecond pulse with a narrow spectral linewidth. This nearly transform-limited pulse was succeedingly amplified by a triple-pass off-axis amplifier. The pulse duration and the spectral linewidth were 60 ps and 9.4 pm, respectively. The amplified pulse was frequency-doubled by second-harmonic generation, producing a 0.5-mJ pulse with no background emission. The potential advantage of this laser in the analysis of dioxin based on supersonic jet/resonance-enhanced multiphoton ionization/mass spectrometry is discussed. 相似文献
139.
Takayuki Ikehara Hideo Kurihara Toshiyuki Kataoka 《Journal of Polymer Science.Polymer Physics》2009,47(5):539-547
The effects of the lamellar growth direction, extinction rings, and spherulitic boundaries of poly(butylene succinate) (PBSU) on the spherulitic growth of poly(ethylene oxide) (PEO) were investigated in miscible blends of the two crystalline polymers. In the crystallization process from a homogeneous melt, PBSU first developed volume‐filling spherulites, and then PEO spherulites nucleated and grew inside the PBSU spherulites. The lamellar growth direction of PEO was identical with that of PBSU even when the PBSU content was about 5 wt %. PEO, which intrinsically does not exhibit banded spherulites, showed apparent extinction rings inside the banded spherulites of PBSU. The growth rate of a PEO spherulite, GPEO, was influenced not only by the blend composition and the crystallization temperature of PEO, but also by the growth direction with respect to PBSU lamellae, the boundaries of PBSU spherulites, and the crystallization temperature of PBSU, TPBSU. The value of GPEO first increased with decreasing TPBSU when a PEO spherulite grew inside a single PBSU spherulite. Then, GPEO decreased when TPBSU was further decreased and a PEO spherulite grew through many tiny PBSU spherulites. This behavior was discussed based on the aforementioned factors affecting GPEO. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 539–547, 2009 相似文献
140.
Naoki Fujita Takayuki Makino Yasuhiro Sakoishi Katsuya Asano Masanobu Kusunoki 《Crystal Research and Technology》2016,51(3):215-219
The relation between O2 pressure and composition in the pulsed‐laser deposition of fluoroapatite was investigated using both on‐axis and off‐axis methods to determine the optimal conditions for obtaining a pure fluoroapatite film without OH groups. Through this, it was found that an O2 pressure of 10 Pa, combined with an off‐axis method, results in P/Ca and F/Ca values (0.6 and 0.2, respectively) that match closely with a stoichiometric composition of Ca10(PO4)6F2. Fourier transform infrared spectroscopy analysis confirmed that this optimized film was almost pure fluoroapatite, with no evidence of any OH groups originating from hydroxyapatite. X‐ray diffraction also revealed that this fluoroapatite film crystallizes with a c‐axis orientation perpendicular to its surface. 相似文献