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51.
52.
Chlorophenols including monochlorophenol, dichlorophenol, trichlorophenol, tetrachlorophenol, and pentachlorophenol in water were extracted into dialkylated cationic surfactant-silica gel admicelles. The dialkylated cationic surfactants such as didecyldimethylammonium bromide (DC10) and didodedyldimethylammonium bromide (DC12) sorbed on silica gel surfaces to form admicelles at pH 9. Approximately 200mg of DC10 was quantitatively sorbed on 1g of silica gel. The sorption further increased by further addition of DC10. This is in contrast to the fact that the maximum sorption of mono-alkylated cetyltrimethyammonium chloride (CTAC) was only ca. 100mg. Based on the fluorescent spectra of a molecular probe, N-phenyl-1-naphthylamine, DC10- and DC12-silica gel admicelles were more hydrophobic than CTAC-silica gel admicelles. The extents of the extraction of chlorophenols into DC10-silica gel admicelles were greater than those into CTAC-silica gel admicelles. However, the extractions to DC12-silica gel admicelles were insufficient due to leakage of DC12 vesicles. Consequently, DC10-silica gel admicelles were the most adequate for concentrating chlorophenols in water. An admicelle column was prepared by passing aqueous buffer solution of DC10 through a Bond Elut Jr. silica gel solid-phase extraction cartridge. It was successfully applied to the 500-fold concentration of chlorophenols including hydrophilic mono-substituted chlorophenol in water samples prior to their HPLC analysis. 相似文献
53.
Nana Kinoshita Chikako Nagasato Taizo Motomura 《Photochemistry and photobiology》2017,93(5):1216-1223
Brown algal swarmers usually exhibit positive or negative phototaxis. Such behaviors influence the increasing or decreasing dispersal distance or colonization on the new substratum. We confirmed that the sign of phototaxis (negative or positive) in male gametes of Mutimo cylindricus was affected by extracellular Ca2+ influx through Ca2+ channels. Under the control condition (10?2 m [Ca2+]), male gametes swimming with a helical rotation of their cell body mostly showed positive phototaxis. At 10?3 m [Ca2+], more than half of the male gametes showed positive phototaxis, whereas the others showed negative phototaxis. From 10?4–10?5 m [Ca2+], the phototactic sign changed to negative. When these negative phototactic gametes were transferred back to the control condition, the phototactic sign reverted to positive. At 10?6 m [Ca2+], some of male gametes showed negative phototaxis, but most showed no phototaxis or flagellar beating. Lanthanum, a Ca2+ channel blocker, affected the sign of phototaxis at 10?4 m [La3+] under 10?2 m [Ca2+], and male gametes mostly showed negative phototaxis. A further increase in [La3+] inhibited phototaxis and flagellar beating. These results pointed out the involvement of Ca2+ channels that were blocked by La3+ in phototaxis and flagellar beating. 相似文献
54.
Katsuhiko Ariga Joshua A. Jackman Nam‐Joon Cho Shan‐hui Hsu Lok Kumar Shrestha Taizo Mori Jun Takeya 《Chemical record (New York, N.Y.)》2019,19(9):1891-1912
The challenges of pollution, environmental science, and energy consumption have become global issues of broad societal importance. In order to address these challenges, novel functional systems and advanced materials are needed to achieve high efficiency, low emission, and environmentally friendly performance. A promising approach involves nanostructure‐level controls of functional material design through a novel concept, nanoarchitectonics. In this account article, we summarize nanoarchitectonic approaches to create nanoscale platform structures that are potentially useful for environmentally green and bioprocessing applications. The introduced platforms are roughly classified into (i) membrane platforms and (ii) nanostructured platforms. The examples are discussed together with the relevant chemical processes, environmental sensing, bio‐related interaction analyses, materials for environmental remediation, non‐precious metal catalysts, and facile separation for biomedical uses. 相似文献
55.
Hajime?Muta Susumu?Kawauchi Mitsuru?SatohEmail author 《Colloid and polymer science》2003,282(2):149-155
The ion-specific swelling behavior of poly(acrylic acid) (PAA) gel prepared by -ray irradiation was investigated as a function of salt concentration in the presence of 0.01 M HCl. The anion specificity for the swelling ratio was similar to that for many kinds of hydrogels, i.e., Cl–<Br–<NO3
–<I–, while the cation specificity proved to be rather unusual, i.e., Mg2+<Ca2+<Li+<Na+<K+<Cs+. In order to find any differences in the hydration of uncharged PAA from that of other polymers having typical polar groups, the hydrogen-bonding hydrations on the relevant polar groups were compared for small molecule analogues with an ab initio molecular orbital calculation. According to the results, the marked deswelling of PAA gel in the presence of strongly hydrated cations was ascribed to the unfavorable hydration to the acidic proton of PAA due to the reduced availability of water oxygen as well as to the destabilization of hydrophobic hydration developing around the uncharged PAA. 相似文献
56.
Tsutomu Kagiya Shizuo Narisawa Taizo Ichida Kenichi Fukui Hisao Yokota 《Journal of polymer science. Part A, Polymer chemistry》1966,4(9):2171-2178
The influence of the addition of ethylene on the γ-ray-induced alternating copolymerization of ethylenimine and carbon monoxide was investigated. A mixture of ethylenimine, carbon monoxide, and ethylene was irradiated to produce a polymer containing these monomeric units. The infrared spectrum of the copolymer showed the characteristic absorption peaks of the secondary amide and ketone bond and was different from that of the reaction product of polyketone with ethylenimine and that of the γ-ray irradiation product of ethylene and poly-ß-alanine. The x-ray diffraction diagram of the copolymer was different from those of poly-ß-alanine and polyketone and exhibited an amorphous structure. Paper chromatographic analysis showed that the hydrolysis product of the copolymer contained ß-alanine and δ-aminovaleric acid. These results indicate that terpolymerization of ethylenimine, carbon monoxide, and ethylene took place under γ-ray irradiation and gave an amorphous polymer containing the units \documentclass{article}\pagestyle{empty}\begin{document}$ \rlap{} ({\rm CH}_{\rm 2} {\rm CH}_{\rm 2} {\rm NHCO}\rlap{}),\rlap{} ({\rm CH}_{\rm 2} {\rm CH}_{\rm 2} {\rm CO}\rlap{}),{\rm and}\rlap{} ({\rm CH}_{\rm 2} {\rm CH}_{\rm 2} {\rm CH}_{\rm 2} {\rm CH}_{\rm 2} {\rm NHCO}\rlap{}) $\end{document} 相似文献
57.
Youichiro Naito Yoshihisa Inoue Taizo Ono Yoshio Arakawa Chikara Fukaya Kazumasa Yokoyama Yoshiro Kobayashi Kouichi Yamanouchi 《Journal of fluorine chemistry》1984,26(4):485-497
Electrochemical fluorination of N-methyldecahydroquinoline afforded mainly a mixture of and N-(F-methyl)-F-decahydroquinoline, their rearranged isomers and F-propyl-F-cyclohexane arising from the cleavage at carbon-nitrogen bonds, in a ratio of approximately 2:4:6:3. N-Methyldecahydroisoquinoline was also fluorinated electrochemically to give a mixture of and N-(F-methyl)-F-decahydroisoquinoline, their rearranged isomers and 1-(F-ethyl)-2-(F-methyl)-F-cyclohexane in a ratio of approximately 4:4:6:1. No correlation was found between the and ratio of starting materials and that of the corresponding perfluorinated amines. Fluorination of N-methyl-1,2,3,4-tetrahydroquinoline gave much lower yields. 相似文献
58.
Shinsuke Yamanaka Hiroaki Muta Shin-ichi Kobayashi 《Journal of solid state chemistry》2004,177(10):3484-3489
Polycrystalline samples of strontium series perovskite type oxides, SrHfO3 and SrRuO3 were prepared and the thermophysical properties were measured. The average linear thermal expansion coefficients are 1.13×10−5 K−1 for SrHfO3 and 1.03×10−5 K−1 for SrRuO3 in the temperature range between 423 and 1073 K. The melting temperatures Tm of SrHfO3 and SrRuO3 are 3200 and 2575 K, respectively. The longitudinal and shear sound velocities were measured by an ultrasonic pulse-echo method at room temperature in air, which enables to evaluate the elastic moduli and Debye temperature. The heat capacity was measured by using a differential scanning calorimeter, DSC in high-purity argon atmosphere. The thermal diffusivity was measured by a laser flash method in vacuum. The thermal conductivities of SrHfO3 and SrRuO3 at room temperature are 5.20 and 5.97 W m−1 K−1, respectively. 相似文献
59.
Taizo?KawauchiEmail author Naoki?Nagatsuka Katsuyuki?Fukutani 《Hyperfine Interactions》2016,237(1):73
Electronic excitation of materials is of fundamental and technological importance and interest in terms of photoinduced phase transition, photovoltaics, and photocatalysis. In the present study, photoexcitation of Fe2 O 3 epitaxially grown on rutile TiO2(100) was investigated with conversion electron Mössbauer spectroscopy (CEMS) under dominantly visible-light irradiation. 57Fe was deposited on the substrate at a substrate temperature of 973 K, and the resulting film was characterized by RHEED and XPS. After deposition of Fe on TiO2(100), it was found that Fe was oxidized to Fe 3+, and the structure was analyzed to be the rhombohedral phase of Fe2 O 3. While the CEMS spectrum without light irradiation showed a quadrupole splitting of 0.80 mm/s with an isomer shift of +0.25 mm/s, an additional component with a quadrupole splitting of 0.85 and an isomer shift of +0.67 mm/s was observed under light irradiation. The latter component corresponds to a reduced state of Fe at the octahedral site surrounded by oxygen atoms. The lifetime of this photoexcited state is discussed. 相似文献
60.