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11.
12.
Naoya Inazumi Shunzo Yamamoto Yoshimi Sueishi 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(1-2):33-39
The inclusion complexation of p-sulfonatocalix[6]arene (Calix-S6) with three kinds of phenothiazine dyes was studied spectrophotometrically in a mixture
of a room-temperature ionic liquid [bmim]BF4 (1-butyl-3-methylimidazolium tetrafluoroborate) and ethanol. We have determined the association constants of Calix-S6 with
phenothiazine dyes under external static pressure up to 767 bar in the [bmim]BF4-ethanol and alcohol-water mixtures. With increasing external pressure, the inclusion equilibrium in the alcohol-water mixtures
was shifted to the dissociation side. Conversely, the inclusion equilibrium of methylene blue (MB) and azure A (AA) in the
ionic liquid mixture was shifted to the association side. From the analysis of the pressure effects, the reaction volumes
ΔV for inclusion complexation were estimated as −7 to 9 cm3 mol−1 in the [bmim]BF4-ethanol mixture and 20–32 cm3 mol−1 in the alcohol-water mixtures. Based on the results, we have suggested that there is a competing complexation between the
included dye and [bmim]BF4 molecules in the ionic liquid. 相似文献
13.
Hiroyuki Ohno Yoshitaka Ogata Eishun Tsuchida 《Journal of polymer science. Part A, Polymer chemistry》1986,24(11):2959-2969
Small unilamellar liposomes were prepared in an aqueous medium by the sonication of phospholipids containing diene or triene groups in their hydrocarbon acyl chains. These liposomes were polymerized by gamma-ray irradiation. Conversion of polymerization was successively followed by UV spectrometry. Diene-type lipid liposomes were revealed for which a gamma-ray dose of 0.8 Mrad was required for complete polymerization and which were polymerized more easily than triene-type lipid liposomes. Triene-type lipids required 2.3 Mrad gamma ray to polymerize them completely. Contrary to UV-irradiation polymerization, there was no concentration dependence on the polymerization. Structure of the polymerized liposomes were confirmed by electron microscopy as small unilamellar liposomes. Study on the leakage of fluorescein from inner aqueous phase of the polymerized liposomes revealed that polymerized triene-type liposomes were relatively more stable than the polymerized diene-type liposomes. 相似文献
14.
Chiaki Azuma Takao Mitsuboshi Kohei Sanui Naoya Ogata 《Journal of polymer science. Part A, Polymer chemistry》1980,18(3):781-797
cis-1,4-Polybutadiene and polypentenamer having pendant functional groups such as formyl, aldoxime, hydroxymethyl, or cinnamoyloxymethyl groups have been prepared, and some of their properties were investigated in terms of structural effect on physical properties of these polymers. cis-1, 4-Polybutadiene and polypentenamer having a different content of formyl group were prepared by the hydroformylation reaction with rhodium catalyst under mild conditions. The pendant formyl group was reduced to a hydroxymethyl group by using various reducing agents such as sodium borohydride or sodium trimethoxyborohydride which were effective to avoid a crosslinking reaction among the formyl groups. Glass transition temperature of polypentenamer having hydroxymethyl groups increased with increasing the content of the hydroxymethyl groups in the polymer. Cinnamoyl group was introduced into the polypentenamer having hydroxymethyl groups by reacting with cinnamoyl chloride so as to prepare a photosensitive rubber. The relationships between the photosensitivity of the cinnamoylated polypentenamer and the mobility of polymer main chains have been elucidated. A linear relationship between the photodimerization rate constant and the difference between ultraviolet (UV) irradiation temperature and the glass transition temperature of the polymer was found. It has become apparent that the photosensitivity of cinnamoylated polypentenamer can be estimated by the glass transition temperature of the original polymer, UV irradiation temperature, activation energy of the dimerization, and γ, which is a coefficient of the relationship between the photosensitive group concentration and the glass transition temperature of the polymer. 相似文献
15.
Masaru Kurihara Naoya Yoda 《Journal of polymer science. Part A, Polymer chemistry》1967,5(7):1765-1781
Fully aromatic polyquinazolinediones of high molecular weight were prepared by the cyclopolycondensation reaction of 4,4′-diamino-3,3′-biphenyldicarboxylic acid with aromatic diisocyanates. The poly(phosphoric acid) solution polymerization techniques yielded tractable poly(urea acid), which was converted to polyquinazolinediones by thermal cyclodehydration at 300–400°C. under reduced pressure. The polyquinazolinediones thus obtained have excellent thermal stability both in nitrogen and in air. The poly(urea acid) is soluble in dimethyl sulfoxide, and films can be cast from the polymer solution of poly(urea acid) (ηinh = 0.8 to 1.8). The films are made tough by being heated in nitrogen or under reduced pressure at 300–400°C. The polymerization mechanism of the cyclopolycondensation reaction was studied, and it was established that the polymerization proceeded through the formation of tractable poly(urea acid), Structure (I), of high molecular weight, followed by cyclodehydration, yielding poly(1,2-dihydro-2-imino-4H-3,1-benzoxazin-4-one), Structure (II). On subsequently being heated this undergoes intramolecular rearrangement along the polymer chain, giving the thermodynamically stable polyquinazolinedione, Structure (III). 相似文献
16.
Masayoshi Watanabe Tadashi Iida Kohei Sanui Naoya Ogata Tadahiko Kobayashi Zentaro Ohtaki 《Journal of polymer science. Part A, Polymer chemistry》1984,22(6):1299-1307
Novel polyamides that contain tetrathiafulvalene (TTF) moieties were synthesized by direct polycondensation of Δ2,2′ -bi-1,3-dithiole-4,4′(5′)-dicarboxylic acid with aromatic diamines in the presence of triphenylphosphine, hexachloroethane, and pyridine. Complexes of these polyamides with bromine were TTF cation radical () salts which resulted from the charge transfer of TTF moieties to bromine. The electrical conductivity of undoped polyamides increased with a decrease in diamine length. By doping the bromine the conductivity of the polyamides was enhanced by 3–5 orders of magnitude and reached 10?5–;10?9S cm?1. Maximum conductivity was observed at the doping ratio of [Br]/[repeat unit] < 1. The electrical conduction in the bromine complexes may be attributed to the hopping of odd electrons of between TTF moieties. 相似文献
17.
Radioprotective effect has been observed in mice which have subcutaneously received a single dose of abundant inorganic zinc or manganese 24 hours before gamma-ray irradiation with a sublethal dose. Mechanism of the radioprotection has been suggested to be an abundant production of metallothionein (MT) induced by the metals. But process of the protection might be more complicated because immunological and hematopoietic functions are remarkably inhibited by the irradiation and many zinc binding-compounds with biological functions are known at present. Furthermore, the effect of these metals has been observed by the administration only before the irradiation. Radioprotective effect was shown in mice which were administered with not only zinc and manganese, but also magnesium. It seems that mechanism of the radioprotection of magnesium is different from that of zinc or manganese since magnesium is not known to induce MT production. It was observed that the relative concentration ratio of radioactivity in tissues and organs at 7th day (after injection of 65Zn) showed a marked difference between in irradiated and non-irradiated mice. 相似文献
18.
Kenjiro Hattori Tomoko Takeuchi Mika Ogata Ayumi Takanohashi Katsuhiko Mikuni Katsuyoshi Nakanishi Hideo Imata 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):339-342
We obtained the association constants Ka of estrogen (E2) and environmental chemicals by the surface plasmon resonance (SPR) assay using the immobilized mono-6-O-α-maltosyl-β-CD (G2βCD) compared with the immobilized β-CD and the immobilized estrogen receptor (ER). The association behavior of G2βCD was shown as a ER model compound. The calibration curve was determined by the initial rate of association depending on
the various concentrations, and the minimum detectable concentrations in the order of parts per billion were calculated. The
SPR assay has advantages that the pre-treatment of the sample is not necessary and the immobilized ligand is stable and useful
for the repeated measurement. 相似文献
19.
Yumi Arai Masayoshi Watanabe Kohei Sanui Naoya Ogata 《Journal of polymer science. Part A, Polymer chemistry》1985,23(12):3081-3093
Polycondensation methods greatly influence the molecular weight distribution of poly(hexamethylene sebacamide) (nylon 610) as determined by gel permeation chromatography (GPC). The ratio of weight average molecular weight to number average molecular weight (Mw/Mn) was used as a measure for estimating the molecular weight distribution. The Mw/Mn ratios of nylon 610 obtained from melt, solid phase, and high temperature polycondensation methods were 2 to 3.5, which were expected values for the most probable distribution. However, those for polymers obtained from the direct polycondensation in the presence of triphenylphosphine, interfacial polycondensation and low temperature polycondensation using an acid chloride varied over a wide range from 3.5 to 8.5. The effect of the kind of organic solvents in the interfacial method on the Mw/Mn ratios was especially large, and the molecular weight distribution could be controlled to some extent by selecting an appropriate solvent. 相似文献
20.
Yuko Ogata Pamela M. Quizon Nancy S. Nightlinger Pongkwan Sitasuwan Casey Snodgrass L. Andrew Lee Jeffrey D. Meyer Richard S. Rogers 《Rapid communications in mass spectrometry : RCM》2022,36(3):e9222