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Alphas5-casein was more sensitive to calcium than αs1-casein, requiring 2 mM calcium chloride for 80% protein precipitation as compared to 8 mM for αs1-casein. Ability of αs5-casein to interact with κ-casein forming micelles resistant to precipitation with calcium was less than that of αs1-casein.Molecular weights determined by the differential boundary method in an ultracentrifuge were 65,750 and 31,800 for αs5-casein and for reduced αs5-casein (the equimolar mixture of αs3- and αs4-caseins). Elution of αs5-casein at the second half of the κ-casein rich peak on Sephadex G-100 at pH 10.8 was ascribed to the molecular size of αs5-casein. 相似文献
53.
The spin-spin relaxation time, T2, for DCP-cured natural rubber with various crosslink densities, ve, has been measured under various deformation. T2 is separated into two components: one is the long T2 component, T2L, for the mobility of amorphous network chains, the other is the short one, T2S, for that of the strain-induced crystalline chains. T2L decreased exponentially with increasing extension ratio,α, and the decreasing rate was more remarkable with increasing ve. The α and ve dependence of T2L has been quantitatively explained by the equation experimentally derived by Nishi et al.T2L under various extension increased and became almost constant with increasing temperature, while the corrected fraction of T2S, T2S (%), gradually decreased. The apparent melting point, Tm, at which the corrected T2S (%) was zero under various deformation was determined. The α dependence of Tm, has been discussed by using Flory's equation. 相似文献
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Hidetoshi Fukuyama Takahiko Sasaki Ken Yokoyama Yasushi Ishikawa 《Journal of Low Temperature Physics》2002,126(3-4):1067-1080
The way how the Landau diamagnetism emerges in finite two-dimensional systems, disc and ring, has been clarified by examining both the field dependences of the magnetization and the spatial distribution of the persistent currents induced by the magnetic field. 相似文献
58.
Seiichiro Imamura Tohru Nakai Hiroyoshi Kanai Takeshi Shiono Kazunori Utani 《Catalysis Letters》1996,39(1-2):79-82
Titania-silica mixed oxide was prepared by hydrolyzing tetraethyl orthosilicate and tetraisopropyl titanate(IV) with a mixture of ethanol and 0.01 N aqueous acetic acid. Surface Ti content, BET surface area, and the number of acid sites increased with an increase in 0.01 N aqueous acetic acid. Thus hydrolysis of both alkoxides occurred simultaneously with a large amount of the acetic acid solution, and there was extensive interaction between TiO2 and SiO2 phases. With small amount of 0.01 N aqueous acetic acid, however, titanium hydroxide was first formed and, then, it was covered with the silica phase produced in a later stage of the hydrolysis. Increase in the acetic acid solution also led to the formation of a large amount of tetrahedral Ti species, which were active for the epoxidation of oct-1-ene usingt-butyl hydroperoxide as an oxidant. 相似文献
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Nakai M. Akui S. Seno K. Meguro T. Seki T. Kondo T. Hashiguchi A. Kawahara H. Kumano K. Shimura M. 《Solid-State Circuits, IEEE Journal of》2005,40(1):28-35
High-performance and low-power microprocessors are key to PDA applications. A dynamic voltage and frequency management (DVFM) scheme with leakage power compensation effect is introduced in a microprocessor with 128-bit wideband 64-Mb embedded DRAM. The DVFM scheme autonomously controls clock frequency from 8 to 123 MHz in steps of 0.5 MHz and also adaptively controls supply voltage from 0.9 to 1.6 V in steps of 5 mV, achieving 82% power reduction in personal information management scheduler application and 40% power reduction in MPEG4 movie playback. This low-power embedded microprocessor, fabricated with 0.18-/spl mu/m CMOS embedded DRAM technology, enables high-performance operations such as audio and video applications. As process technology shrinks, this adaptive leakage power compensation scheme will become more important in realizing high-performance and low-power mobile consumer applications. 相似文献