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31.
32.
[reaction: see text] This paper describes the selective formation of a cyclic tetramer from a readily synthesized metalloporphyrin with two self-complementary quadruple hydrogen-bonding units. The extremely strong quadruple hydrogen-bonding unit, 2-ureido-4[1H]-pyrimidinone, enabled the formation of a stable cyclic tetramer based on a tetraphenylporphyrin derivative over a wide concentration range. This hydrogen-bonded tetramer is a new functional unit for use in a higher-ordered architecture of a supramolecular porphyrin assembly. 相似文献
33.
A non‐volatile, bistable, and rewritable organic memory device was successfully fabricated with the layers of poly(2,2,6,6‐tetramethylpiperidine‐1‐oxyl methacrylate) (PTMA) and poly(methyl methacrylate) (PMMA) containing silver salt. The PTMA layer was employed as a p‐dopable material, while the silver salt‐dispersed PMMA layer acted as an n‐dopable material. The ON–OFF ratio between low‐conductivity and high‐conductivity states amounted to more than four orders of magnitude, and the retention time was longer than 103 sec. The device was characterized by excellent rewritability. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
34.
Inukai J Miyatake K Ishigami Y Watanabe M Hyakutake T Nishide H Nagumo Y Watanabe M Tanaka A 《Chemical communications (Cambridge, England)》2008,(15):1750-1752
A luminescent porphyrin dye film has been coated onto a transparent separator on the cathode side of a direct methanol fuel cell (DMFC) to visualise clearly oxygen distribution under operating conditions by analysing emission from the dye. 相似文献
35.
Oyaizu K Ando Y Konishi H Nishide H 《Journal of the American Chemical Society》2008,130(44):14459-14461
Redox polymer layers with 2,2,6,6-tetramethylpiperidin-1-oxyl-4-yl (TEMPO) groups showed nernstian adsorbate-like electrochemical behaviors up to submicrometer thicknesses, based on a fast charge propagation within the bulk layer and persistency in electrolyte solutions. 相似文献
36.
Moreno-Villoslada I González F Rivera L Hess S Rivas BL Shibue T Nishide H 《The journal of physical chemistry. B》2007,111(22):6146-6150
Aromatic-aromatic interactions are found between the cationic molecule 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) and the molecule poly(sodium 4-styrenesulfonate) (PSS) which makes the overall interaction of TTC with PSS more intense than the interaction with other polyanions containing sulfonate groups and produces a decrease on the redox ability of TTC. Diafiltration was used to compare the binding of TTC to PSS, poly(sodium vinylsulfonate) (PVS), and the more hydrophobic poly(sodium 2-(N-acrylamido)-2-methyl-propanesulfonate) (PAMPS). The UV-vis spectrum of TTC is changed in the presence of the aromatic polyanion. The 1H NMR signals of TTC are broadened and shifted in the presence of PSS, suggesting the occurrence of pi-pi interactions. Moreover, nuclear Overhauser effects (NOE) between the TTC and PSS protons are found. Possible structures for the complex are proposed. 相似文献
37.
Sung Ick Park Hiromi Sakai Shinji Takeoka Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1997,8(6):366-370
A polymer composite film of hemoglobin (Hb–polymer film) was prepared by the casting of an Hb–polymer mixed solution (weight ratio of Hb to polymer is 1 to 1). The percentages of O2 and CO saturation of the Hb–dextran film were 46% and 70%, respectively. In the Hb solution, 100% saturation was observed for both ligands, and a humidified Hb–dextran film also showed 100% saturation. Water molecules would provide flexibility to the matrix polymer and promote a structural change in the Hb from a tense state (T) to a relaxed state (R). Thus the ligand binding to the Hb in the polymer films was strongly affected by the degree of interaction of Hb with the matrix polymers and the physical properties of the polymers. Inositol hexaphosphate (IHP) worked as an allosteric effector even in the solid polymer film and lowered the oxygen affinity of Hb. The O2 transport through an Hb–polyethyleneimine (PEI) film with IHP showed the facilitated O2 transport in comparison with the film without IHP because of the high dissociation rate of O2 from Hb with IHP. © 1997 John Wiley & Sons, Ltd. 相似文献
38.
Hiroyuki Nishide Makoto Miyasaka Eishun Tsuchida 《Angewandte Chemie (International ed. in English)》1998,37(17):2400-2402
An average spin quantum number of 7/2 is displayed by the star-shaped, π-conjugated polyradical 1 , even with a spin concentration of 0.8 per monomer unit. Polymer 1 is stable at room temperature, and it is a powerful candidate for the synthesis of a feasible polymer with very high spin. 相似文献
39.
Kimura H Fujiwara T Katoh T Nishide K Kajimoto T Node M 《Chemical & pharmaceutical bulletin》2006,54(3):399-402
(-)-Epibatidine, an excellent candidate of non-opioidal anesthesia, was formally synthesized in short steps from di-(l)-menthyl (R)-allene-1,3-dicarboxylate that was facilely prepared as a single isomer by means of crystallization-induced asymmetric transformation from a diastereomer mixture of (R)- and (S)-allene-1,3-dicarboxylates. Taking advantage of the chiral synthesis, derivatives of (-)-epibatidine were also prepared for targeting diagnostic agents that could bind nicotinic acetylcholine receptors (nAChRs) in the mammalian central nerve system. 相似文献
40.
Hiromi Shinohara Hirokazu Shibata Dieter Whrle Hiroyuki Nishide 《Macromolecular rapid communications》2005,26(6):467-470
Summary: A membrane of a cobalt tetraazaporphyrin polymer complex was prepared with a nanometer thickness and used as an oxygen‐facilitated transport membrane. Rapid and reversible oxygen binding to the cobalt tetraazaporphyrin complex with a polymeric imidazole ligand was observed at low temperature. Oxygen transport through the membrane was facilitated and a high (oxygen/nitrogen) permselectivity of 28 was obtained.