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101.
Yasuhiro Morisaki Keita Ohashi Hai‐Sub Na Yoshiki Chujo 《Journal of polymer science. Part A, Polymer chemistry》2006,44(16):4857-4863
We successfully synthesized the first conjugated polymer containing a bismuth atom in the conjugated main chain by incorporating a bismuth atom into the cyclopentadiene framework (bismole), which was constructed by a polymer reaction. A synthetic procedure and characterization of the obtained polymers were discussed. This bismole‐containing conjugated polymer exhibited moderate bluish green photoluminescence in solution. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4857–4863, 2006 相似文献
102.
Gakuse Hoshina Shigeru Ohba Naoko Tsuchiya Tetsuhiko Isobe Mamoru Senna 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e191-e192
The title mononuclear iron(II) complex, [Fe(C12H8N2)3](NCS)2·3H2O, has a slightly distorted octahedral coordination. One of the thiocyanate ions and one of the water molecules of crystallization show positional disorder. 相似文献
103.
104.
105.
Naoko Yoshie Mariko Watanabe Hitomi Araki Kazuki Ishida 《Polymer Degradation and Stability》2010,95(5):826-6079
Remending properties of a network polymer with reversible reactivity are described. The network structure is constructed by a Diels-Alder (DA) reaction between furyl-telechelic poly(ethylene adipate) (PEAF2) and a tris-maleimide, M3. When a film sample was cut into two pieces and the cut surfaces were kept in contact with each other at 60 °C, rejoining of the cut pieces was observed. This mending was induced by the reversible cross-linking reaction bridging the cut surfaces. At the cut front, the “weak” DA adducts are selectively dissociated sacrificially to release the stress so as to protect the chemical structure of the prepolymer and the linker against the scission or degradation. The dissociated furan and maleimide readily reconnect by forward DA reaction to mend the material. The remending was also observed for the samples kept at room temperature after melting at 60 °C. So, the PEAF2 network polymer is a thermo-responsive mendable material in which crack healing is induced by a prompt thermal stimulus. 相似文献
106.
Yuya Shinohara Naoko Yamamoto Hiroyuki Kishimoto Yoshiyuki Amemiya 《Journal of synchrotron radiation》2015,22(1):119-123
X‐ray photon correlation spectroscopy (XPCS) of swollen rubber containing spherical silica nanoparticles is reported. It is shown that irradiation by intense X‐rays leads to the breakdown of cross‐links, thereby inducing the local rearrangement of silica nanoparticles. This rearrangement process depends on the cross‐link density and is characterized by a compressed exponential relaxation with aging behaviour, which resembles a common feature of complex fluids observed with XPCS. 相似文献
107.
Sakai-Kato K Kato M Nakajima T Toyo'oka T Imai K Utsunomiya-Tate N 《Journal of chromatography. A》2006,1111(2):127-132
Positively charged starch derivatives were used to modify the inner surface of fused-silica capillaries by addition to running buffer, which were subsequently employed in capillary electrophoresis (CE). Capillaries coated with the cationic starch derivatives were shown to generate a stable, reversed electroosmotic flow (EOF) in the investigated pH range of 3-9. The presented coating procedure was fast, based on a simple rinsing protocol where the polymer created a physically adsorbed, cationic polymer layer. Among the additives studied, a quaternary ammonium starch derivative showed a fast EOF mobility and effectively suppressed the adsorption of proteins. The intra- and inter-day reproducibility of the coating referring to the EOF mobility were satisfactory with relative standard deviation (RSD) of 0.27 and 1.67%, respectively. The coating enabled separation of some protein mixtures including basic proteins within l3 min with efficiencies up to 280,000 plates/m. In addition, this cationic starch derivative possessed a good solubility (about 100mg/mL), and it does not significantly contribute to the background adsorption in the UV region of 190-400 nm. 相似文献
108.
Nakanishi T Miyashita N Michinobu T Wakayama Y Tsuruoka T Ariga K Kurth DG 《Journal of the American Chemical Society》2006,128(19):6328-6329
Fullerene derivatives bearing long alkyl chains epitaxially adsorb on the basal plane of graphite forming well-ordered one-dimensional lamellae. Within the lamellae, the C60 moieties are organized in a zigzag-type fashion. The ordering is mainly governed by the substitution pattern and chain length of the alkyl chains. The electrochemical activity of the C60 groups is fully maintained in the surface-confined assemblies. 相似文献
109.
Kobayashi S Shinohara H Tabata K Yamamoto N Miyai A 《Chemical & pharmaceutical bulletin》2006,54(12):1633-1638
The aim of this study was to elucidate the structure-activity relationship of bisphenol A (BPA) analogs using absolute hardness (eta) and absolute electronegativity (chi) (chemical hardness) and to design a non-estrogen active BPA. To determine the structure-activity relationships of BPA analogs, we investigated MCF-7 cell proliferation stimulated by BPA analogs and an eta-chi diagram based on the electronic structure of the BPA analogs. The results show that the actions of the environmental hormones BPA analogs have two chemical properties; (i) 'stereo structure-controlled' and (ii) 'electronic structure-controlled' estrogen-like chemical activities. Therefore, we designed and synthesized BPA analogs which do not possess these 2 characteristics, ((i) and (ii)), and demonstrate the non-estrogen activity of the analog. 相似文献
110.
Organocatalytic direct asymmetric aldol reactions in water 总被引:2,自引:0,他引:2
Mase N Nakai Y Ohara N Yoda H Takabe K Tanaka F Barbas CF 《Journal of the American Chemical Society》2006,128(3):734-735
We have developed direct asymmetric cross-aldol reactions that can be performed in water without addition of organic solvents. A bifunctional catalyst with a long hydrophobic alkyl chain efficiently catalyzed the reactions and afforded the desired aldol products in excellent yield with high enantiomeric excess, even when only an equal molar ratio of the donor and acceptor was used. These results reveal an effective design strategy for the development of aqueous organocatalytic systems. 相似文献