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991.
Nakazawa T Azumi R Sakai H Abe M Matsumoto M 《Langmuir : the ACS journal of surfaces and colloids》2004,20(24):10583-10590
The structures and photoreactions of Langmuir and Langmuir-Blodgett (LB) films of an amphiphilic spiropyran, 1',3'-dihydro-3',3'-dimethyl-6-nitro-1'-octadecyl-8-(docosanoyloxymethyl)spiro[2H-1-benzopyran-2,2'-(2H)-indole] (SP), mixed with n-alkane are investigated. The mixing ratio was fixed at 1/2 for SP/n-alkane. The surface pressure-area isotherms of SP/octadecane are categorized into two regimes: a low-temperature regime where octadecane is packed with the alkyl chains of SP, and a high-temperature regime where the addition of octadecane does not influence the isotherms significantly. The temperature dividing the two regimes is related with the melting point of the n-alkane mixed with SP in the bulk. UV irradiation of the Langmuir film in the high-temperature regime gives rise to light-induced J-aggregation, whereas that in the low-temperature regime causes only the isomerization of SP to the corresponding merocyanine, indicating that J-aggregation is hindered by the presence of n-alkane in the low-temperature regime. IR external reflection spectroscopy of the Langmuir films shows that n-alkane is released from the film during J-aggregation. The structural changes of the mixed Langmuir and LB films during J-aggregation are almost the same with those of the films of pure SP. 相似文献
992.
993.
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995.
Hideki Sakurai Toshifumi Hirose Akira Hosomi 《Journal of organometallic chemistry》1975,86(2):197-203
The intramolecular hydrosilylation of (4-pentenyl)hydrosilanes with transition metal salt catalysts afforded five- and six-membered ring-closure products in high yields, with the former predominating. This has been rationalized in terms of a reaction scheme based on the Harrod—Chalk mechanism in which both Si-metal and C-metal bonds were involved. The seven-membered intermediate leading to the six-membered ring products is apparently less favorable than the six-membered intermediate. However, with dicobalt octacarbonyl, no ring closure occurred, and only izomerization was observed. 相似文献
996.
Molecular-dynamics studies of binary mixtures of Lennard-Jones fluids with differing component sizes
Molecular-dynamics calculations have been carried out for six pure liquids and three binary mixtures of Lennard-Jones fluids with differing component sizes and attractive interactions. Internal energies, radial-distribution functions, velocity autocorrelation functions and self-diffusion coefficients have been calculated and are discussed together with our previous results. The three mixtures obey the Lorentz-Berthelot rules and show endothermic mixing. The excess internal energy ΔUE of mixtures with equal-sized components is symmetrical with respect to the mole fraction, but those for mixtures of different-sized components become asymmetrical. A comparison is made between the present ΔUE data and those for real mixtures. 相似文献
997.
Hideki Fujiwara Kazufumi Okazaki Kunio Goto 《Journal of Polymer Science.Polymer Physics》1975,13(5):953-960
Mechanical degradation and mechanochemical polymerization in polystyrene–styrene–cyclohexanone mixtures have been studied by ultrasonic irradiation at 60°C. The number of fresh polymer chains after the degradation is 2 × 10?5 mole l?1 hr?1. The rate equations for mechanical scission and mechanochemical polymerization have been deduced. The rate equation for mechanical scission was found to be in agreement with the expression of a previous paper. In addition, the rate equation for mechanochemical polymerization is not essentially different from that for the general radical polymerization in the presence of solvents. The kinetic chain length for polymeric free radicals in the polymerization process has been calculated. The mechanochemical polymerization of styrene was initiated by only one of the two kinds of end radicals after mechanical scission of polystyrene. The molecular weight distributions of the samples after the degradation and the polymerization have been compared and discussed. 相似文献
998.
999.
Applications of the complex interpolation method to a von Neumann algebra: Non-commutative Lp-spaces
Hideki Kosaki 《Journal of Functional Analysis》1984,56(1):29-78
Non-commutative Lp-spaces, 1 < p < ∞, associated with a von Neumann algebra are considered. The paper consists of two parts. In part I, by making use of the complex interpolation method, non-commutative Lp-spaces are defined as interpolation spaces between the von Neumann algebra in question and its predual. Also, all expected properties (such as duality and uniform convexity) are proved in the frame of interpolaton theory and relative modular theory. In part II, these Lp-spaces are compared with Haagerup's Lp-spaces. Based on this comparison, a non-commutative analogue of the classical Stein-Weiss interpolation theorem is obtained. 相似文献
1000.
Hideki Kurose 《Journal of Functional Analysis》1981,43(2):193-201
The aim of this paper is to study the closed derivations in C(I) induced by non-atomic signed measures with support I and to give an example of a non quasi well-behaved closed derivation in C(I). 相似文献