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111.
Nakata K Sakamoto M Taguchi S Yoshida N Shimazu K 《Journal of colloid and interface science》2005,288(2):634-637
The water-insoluble poly-beta-cyclodextrin (poly-CD)/Nafion composite film was easily prepared by casting a mixed solution of poly-CD and Nafion onto substrate plates. FT-IR measurements showed that the 50/50 wt% poly-CD/Nafion composite film remained stable on the glass and quartz substrates after immersion in water for more than 3 h, while a pure poly-CD film was almost completely dissolved by immersion within 1 h. The film stability was also evaluated from the amount of p-nitrophenol (p-NP) inclusion in the film, which was determined from the decrease in UV-vis absorbance of the p-NP solution into which the film was immersed. The composition dependence of the inclusion amount showed that the film was stable up to 50 wt% CD, but became less stable with further increase in the CD concentration in the film. From the isotherms for the inclusion of p-NP and 1-naphthoate (1-Naph) into the film, the inclusion (stability) constants were determined to be 3.7x10(3) M(-1) and 1.9x10(2) M(-1), respectively. These results show that the selective inclusion of CD is retained after preparation of the composite film. 相似文献
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114.
Shinji Nishitani Nobuyuki Kurata Yoshiteru Sakata Soichi Misumi Masahito Migita Tadashi Okada Noboru Mataga 《Tetrahedron letters》1981,22(22):2099-2102
To clarify the primary process of photosynthesis, a series of model compounds, in which an octaethylporphyrin and a benzoquinone ring are connected with different lengths of a polymethylene chain, were synthesized and their photophysical properties were investigated. 相似文献
115.
The energy transfer process to guest molecule5 m poly(N-vinylcarbJZole) films WJS directly nir.isurcd In (lie film con- taining pciylencihc sandwich excimer site opcralcs as an cncrEy donor, while the evciple't si-itc composed ofthccaiba2olc- dirnettiyl IcrcphtliaJate pair is fornied by trapping tlie migrating monomer fluorescent state. 相似文献
116.
In the radiolysis of water vapor containing small concentrations of cyclohexane, the principal products which account for about 98% of all end products are found to be hydrogen, cyclohexene, and bicyclohexyl. Cyclohexene and bicyclohexyl yields were determined over a range of temperatures (70–200°C), total pressures (50–2400 torr), and total doses (0.15–2.0 Mrad). The disproportionation–combination ratio k/k for c-C6H11 radicals could be determined as 0.56 ± 0.01 from the ratio of cyclohexene to bicyclohexyl yield. By using c-C6D12, the ratio k/k for c-C6D11 radicals is found to be 0.38 ± 0.01. Comparison of the reactivity pattern of C6H11 and C6D11 radicals leads to (k)/(k)/(k/k) = 1.47 ± 0.02. The corresponding values for the reactions of c-C6H11 with c-C6D11 were also determined. 相似文献
117.
Nomura A Uyeda TQ Yumoto N Tatsu Y 《Chemical communications (Cambridge, England)》2006,(34):3588-3590
To design a nanoscale biodevice that can be controlled by an external stimulus, we have introduced photochemical switching peptides derived from the kinesin C-terminus domain into the kinesin-microtubule in vitro motility system. 相似文献
118.
Spectroscopic and thermodynamic investigations on complexation of naphthalene-appended amino-beta-cyclodextrins 1 and 2 with cyclic alcohols (cyclohexanol and cycloheptanol) and acyclic alcohols (1-pentanol, 2-pentanol, 1-hexanol, and 1-heptanol) have been carried out. Host 1 exhibits a drastic fluorescent enhanced-signal change in the presence of alcohol guests in aqueous solution. [structure: see text] 相似文献
119.
Noboru Sato Yuichi Funato Yasuyuki Fukushima Takeshi Momose Mitsuo Koshi Yukihiro Shimogaki 《国际化学动力学杂志》2020,52(6):359-367
We established a gas-phase, elementary reaction model for chemical vapor deposition of silicon carbide from methyltrichlorosilane (MTS) and H2, based on the model developed at Iowa State University (ISU). The ISU model did not reproduce our experimental results, decomposition behavior of MTS in the gas phase in an environment with H2. Therefore, we made several modifications to the ISU model. Of the reactions included in existing models, 236 were lacking in the ISU model, and thus were added to the model. In addition, we modified the rate constants of the unimolecular reactions and the recombination reactions, which were treated as a high-pressure limit in the ISU model, into pressure-dependent rate expressions based on the previous reports (to yield the ISU+ model), for example, H2(+M) → H + H(+M), but decomposition behavior remained poorly reproducible. To incorporate the pressure dependencies of unimolecular decomposition rate constants, and to increase the accuracies of these constants, we recalculated the rate constants of five unimolecular decomposition reactions of MTS using the Rice-Ramsperger-Kassel-Marcus method at the CBS-QB3 level. These chemistries were added to the ISU+ model to yield the UT2014 model. The UT2014 model reproduced overall MTS decomposition. From the results of our model, we confirmed that MTS mainly decomposes into CH3 and SiCl3 at the temperature around 1000°C as reported in the several studies. 相似文献
120.
Noboru Tohge Atsunori Matsuda Tsutomu Minami Yoshihiro Matsuno Shinya Katayama Yoshirou Ikeda 《Journal of Non》1988,100(1-3):501-505
A novel process has been developed to form fine patterns on glass substrates. The process consists of the following steps: (1) coating of gel film on a substrate, (2) patterning on the gel film, and (3) heat-treatment. The key point in this process is the control of hardening of the gel films by the addition of organic polymers such as polyethylene glycol (PEG). The addition of PEG increased the viscosity of the coating solutions and delayed the gelation time, but had little effect on the optical properties of the resultant heat-treated glass films. The newly developed process is expected to be applicable to the formation of the optical devices such as diffraction gratings and pre-groovesof optical memory disks. 相似文献