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Keiki Kishikawa Yuki Furukawa Tomohiro Watanabe Michinari Kohri Tatsuo Taniguchi Shigeo Kohmoto 《Liquid crystals》2017,44(8):1332-1339
Blue phases (BPs) obtained by doping a commercially available liquid crystalline compound (4-butyl-N-(4-ethoxybenzylidene)aniline (EBBA)) with (2R,3R)-2,3-bis(4-octyloxyphenylbenzoyloxy)-N-(hydroxydecyl)succinimide (1) were highly stabilised by the addition of a small amount of alkane diols. Especially, addition of only 0.5 mol% of octane-1,8-diol increased the BP–Iso transition temperature by 10 K and widened the BP temperature range up to 35 K. A model stabilisation mechanism based on the construction of a hydrogen bond network in each disclination zone in BPs was proposed. 相似文献
3.
Wenting Bu Qiuju Guo Jian Zheng Shigeo Uchida 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(2):999-1005
Surface soil samples collected in the Jiuquan region in the downwind area of the Chinese nuclear test site (CNTs) were analyzed for Pu isotopes. The 239+240Pu activities ranged from 0.025 ± 0.009 to 0.89 ± 0.16 mBq g?1, varying significantly with different sampling sites. The Dunhuang city that is located in the southwestern part of the Jiuquan region received the heaviest Pu deposition (239+240Pu activities, 0.23–0.89 mBq g?1). Most of the 240Pu/239Pu isotopic ratios were similar with that of the global fallout. However, the low values (0.080–0.147) observed in three sampling sites further supported the finding of Pu originated from CNTs in that region. 相似文献
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Tatsuro Ouchi Toshio Banba Hiroshi Masuda Tatsuji Matsumoto Shigeo Suzuki Masuko Suzuki 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):959-975
In order to provide a macromolecular prodrug of 5-fluorouracil (5FU) reducing the side effects, having an affinity for tumor cells, and exhibiting strong antitumor activity, the covalent attachments of 5FUs to chitosan and chitosamino-oligosaccharide (COS) through hexamethylene spacer groups via urea, urea bonds were carried out. The effect of prolongation of life was tested in vivo against p388 lyrnphocytic leukemia in female CDF, mice by intra-peritoneal (i.p.) transplantation/i.p. injection and the growth-inhibitory effect on Meth-A fibrosarcoma or MH-134Y heputoma was evaluated in vivo in SPF-C3H/He scl male or Balb/c male mice by subcutaneous (s.c.) implantation/intravenous (i.v.) injection. The effects of the degree of polymerization of chitosan and 相似文献
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Abstract Novel poly(vinylsulfide)s were prepared by addition polymerization using 2,5-bis(2-thia-3-butenyl)-1,4-dithiane (TBD) with a radical initiator for an optical polymer having a high refractive index (nD) and Abbe number (v). Homopolymerization of TBD (72.9% conversion) and copolymerization with acrylonitrile or acrylates having nonpolar groups (50.4–81.3% conversion according to the comonomers used) in a limited composition range yielded hard and transparent polymers suitable for application in optics. The methacrylates used yielded no polymeric product as a result of the copolymerization. The obtained polymers had Tg, nD and v ranging between 41.0–124.0°C, 1.678–1.546 and 34.1–43.8, respectively, except that poly(TBD) did not exhibit Tg below 200°C, and it had the highest nD Most of the polymers have higher nD and v than those of other conventional optical polymers and moreover, their values are comparable to those of flint glasses. The copolymerizability of TBD and the group contribution to nD and v are discussed based on the Q-e scheme and on the Lorentz-Lorenz equation, respectively. This work shows that TBD serves as a useful material for the preparation of polymers having high nD and v along with a Tg of more than 100°C, and that the polymers thus obtained are promising optical materials. 相似文献
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Shigeo Iwayanagi Ikuko Sakurai Tosio Sakurai Tsuneo Seto 《Journal of Macromolecular Science: Physics》2013,52(2):163-177
The crystal structure of trans-1,4-polybutadiene has been reported by Natta et al. to be pseudo-hexagonal below its solid-phase transition temperature. In the present X-ray structure analysis, it is revealed that the crystal belongs to the monoclinic system with the space group P21/a. The unit cell, with the lattice constants a = 8.63 Å, b = 9.11 Å, c = 4.83 Å, and β = 114°, includes four molecular segments. 相似文献
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In the present communication we would like to describe a novel method for the preparation of p-chloromethylstyrene and some reactions of this compound. 相似文献
10.
Hyoe Hatakeyama Shigeo Hirose Tatsuko Hatakeyama Kunio Nakamura Ken Kobashigawa Noriyuki Morohoshi 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):743-750
Abstract Polyurethane (PU) sheets and foams having plant components in their network were prepared by using the following procedure. Polyethylene glycol (PEG) was mixed with one of the following; molasses, lignin, woodmeal, or coffee grounds. The mixture obtained was reacted with diphenylmethane diisocyanate (MDI) at room temperature, and precured PUs were prepared. The precured PUs were heat-pressed and PU sheets were obtained. In order to make PU foam, the above mixture was reacted with MDI after the addition of plasticizer, surfactant (silicone oil), catalyst (di-n-butyltin dilaurate), and droplets of water under vigorous stirring. The glass transition temperature, tensile and compression strengths, and Young's modulus of the PU sheets and foams increased with an increasing amount of plant components. This suggests that saccharide and lignin residues act as hard segments in PUs. It was found that the PUs obtained were biodegradable in soil. The rate of biodegradation of the PUs derived from molasses and coffee grounds was between that of cryptomeria (Cryptomeria japonica) and beech (Fagus sieboldi). 相似文献