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51.
J. Steven Rutt Morihiko Matsumoto Toshihiro Ichino Shiro Nishi 《Journal of polymer science. Part A, Polymer chemistry》1994,32(4):779-787
Latex films composed of fused polybutadiene (PB) and poly (vinyl pyrrolidone) (PVP) particles that contain no ionic, hydroxyl, or amino groups were swelled with lithium salt solutions to yield new polymer electrolyte materials. The latex particle consists of a nonpolar, rubbery core that contains the PB component and a polar, glassy shell that contains the PVP component. The particle core-shell morphology was retained in the solid state, after the latex dispersion medium was removed and the films dried at high temperatures, due to the high Tg of the PVP shell. The films swelled when immersed in lithium salt solutions, and ionic conductivity of swollen films was greater than 10-3 S/cm. Swelling and ionic conduction occurred only in the polar PVP component. Extraction of PVP occurred with extended swelling. © 1994 John Wiley & Sons, Inc. 相似文献
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J. Steven Rutt Toshihiro Ichino Morihiko Matsumoto Shiro Nishi 《Journal of polymer science. Part A, Polymer chemistry》1994,32(4):767-777
The synthesis of polybutadiene (PB) by emulsion polymerization with use of poly (vinyl pyrrolidone) (PVP) stabilizer was investigated. The goal was to prepare flexible latex films that clearly retain particle morphology in the solid state after heat treatment and contain no ionic, hydroxyl, or (primary, secondary) amino groups. The latex particle core composed of PB was nonpolar and rubbery, while the particle shell composed of PVP was polar and glassy. Average particle diameter was measured by the dynamic light scattering technique, and particles were imaged by scanning and transmission electron microscopic analyses. Dialysis of the latices resulted in successful exchange of the dispersion medium without precipitation. © 1994 John Wiley & Sons, Inc. 相似文献
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Koichi Sakano Tsutomu Nakagawa Masahiko Iyoda Masazumi Nakagawa 《Tetrahedron letters》1981,22(28):2655-2658
Tetrakisdehydro[16]annuleno consisting of trisdehydro[16]annulene and bisdehydro[18] annulene has been synthesized. Induction of para- and diamagnetic ring currents in 16- and 18-membered rings, respectively, was clearly recognized by the 1H NMR spectroscopy. A marked suppresion of the diatropicity in the 18π moiety was observed in the same trend as observed in tetrakisdehydro[14]annuleno[16]annulene. 相似文献
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Auger Ionization Beats Photo‐Oxidation of Semiconductor Quantum Dots: Extended Stability of Single‐Molecule Photoluminescence 下载免费PDF全文
Shin‐ichi Yamashita Morihiko Hamada Prof. Shunsuke Nakanishi Hironobu Saito Prof. Yoshio Nosaka Dr. Shin‐ichi Wakida Dr. Vasudevanpillai Biju 《Angewandte Chemie (International ed. in English)》2015,54(13):3892-3896
Despite the bright and tuneable photoluminescence (PL) of semiconductor quantum dots (QDs), the PL instability induced by Auger recombination and oxidation poses a major challenge in single‐molecule applications of QDs. The incomplete information about Auger recombination and oxidation is an obstacle in the resolution of this challenge. Here, we report for the first time that Auger‐ionized QDs beat self‐sensitized oxidation and the non‐digitized PL intensity loss. Although high‐intensity photoactivation insistently induces PL blinking, the transient escape of QDs into the ultrafast Auger recombination cycle prevents generation of singlet oxygen (1O2) and preserves the PL intensity. By the detection of the NIR phosphorescence of 1O2 and evaluation of the photostability of single QDs in aerobic, anaerobic, and 1O2 scavenger‐enriched environments, we disclose relations of Auger ionization and 1O2‐mediated oxidation to the PL stability of single QDs, which will be useful during the formulation of QD‐based single‐molecule imaging tools and single‐photon devices. 相似文献
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Saiki Hasegawa Makoto Sone Masao Tanabiki Morihiko Sato Akihiro Yano 《Journal of polymer science. Part A, Polymer chemistry》2000,38(Z1):4641-4648
Copolymerizations of ethylene and α‐olefin with various zirconocene compounds at a high temperature were carried out to study the relationship between the ligand structure of zirconocene compounds and the copolymerization behavior. All of the indenyl‐based zirconocene compounds in combination with dimethylanilinium tetrakis(pentafluorophenyl)borate/triisobutylaluminum produced only low molecular weight copolymers at a high temperature, regardless of the substituents and bridged structures of the zirconocene compounds. However, zirconocene compounds with a fluorenyl ligand gave rise to a significant increase in the activity and molecular weight of the copolymers by the selection of a diphenylmethylene bridge structure even at a high temperature. Ethylene/1‐hexene copolymers obtained with the fluorenyl‐based catalysts contained inner double bonds accompanied by the generation of hydrogen, presumably because of a C H bond activation mechanism. The contents of the inner double bonds were significantly influenced by the polymerization conditions, including the 1‐hexene feed content, polymerization temperature, and ethylene pressure. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4641–4648, 2000 相似文献
56.
Morihiko Saito 《Selecta Mathematica, New Series》2016,22(4):2017-2057
We show that the Bernstein–Sato polynomial (that is, the b-function) of a hyperplane arrangement with a reduced equation is calculable by combining a generalization of Malgrange’s formula with the theory of Aomoto complexes due to Esnault, Schechtman, Terao, Varchenko, and Viehweg in certain cases. We prove in general that the roots are greater than \(-2\) and the multiplicity of the root \(-1\) is equal to the (effective) dimension of the ambient space. We also give an estimate of the multiplicities of the roots in terms of the multiplicities of the arrangement at the dense edges, and provide a method to calculate the Bernstein–Sato polynomial at least in the case of 3 variables with degree at most 7 and generic multiplicities at most 3. Using our argument, we can terminate the proof of a conjecture of Denef and Loeser on the relation between the topological zeta function and the Bernstein–Sato polynomial of a reduced hyperplane arrangement in the 3 variable case. 相似文献
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We give three new proofs of a theorem of C. Sabbah asserting that the weight filtration of the limit mixed Hodge structure at infinity of cohomologically tame polynomials coincides with the monodromy filtration up to a certain shift depending on the unipotent or non-unipotent monodromy part. 相似文献
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Abe K Amako K Arai Y Asano Y Chiba M Chiba Y Daigo M Emura T Endo I Fukawa M Fukui T Fukushima Y Haba J Haidt D Hayashibara I Hemmi Y Higuchi M Hirose T Hojo Y Homma Y Hoshi Y Ikegami Y Ishihara N Kamitani T Kanematsu N Kanzaki J Kikuchi R Kondo T Koseki T Kurashige H Matsui T Minami M Miyake K Mori S Nagashima Y Nakamura T Nakano I Narita Y Odaka S Ogawa K Ohama T Ohsugi T Okamoto A Ono A Osabe H Oyama T Saito H Sakae H Sakamoto H Sakamoto S Sakano M Sakuda M Sasao N Sato M Shioden M Shirai J 《Physical review letters》1989,63(17):1776-1779