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101.
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Akimi Serizawa Isao Kataoka Itaru Michiyoshi 《International Journal of Multiphase Flow》1975,2(3):247-259
An experimental study of heat and bubble transport in turbulent air-water bubbly flow was carried out by means of tracer techniques. Helium tracer gas concentration data and temperature distributions were used to extract bubble and heat diffusivity information. The results indicated that the turbulent velocity components of the liquid phase play a predominant role in the turbulent transport process. A systematic increase of diffusivity of heat, ?H, with quality and water velocity was observed. An empirical correlation for the diffusivity ratio ?H,TP/?H,SP is presented. The Péclet number, u′covbar|dφ, for bubble dispersion can be approximated by 2.0, independent of the flow variables. The bubble-to-heat diffusivity ratio, φ/?H, approaches unity with increasing quality and water velocity. Momentum transport is also discussed, based on a mixing length theory. 相似文献
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Summary The mechanical and the dynamic properties of various membranes were studied by the ultrasonic-resonance method. The compressibility
of the membranes was in the range from 2.5·10−11 to 5·10−11 cm2/dyn and influenced by several factors such as phase transition, incorporation of cholesterol or proteins and configuration
of proteins. The ultrasonic relaxation was measured for two membrane systems, dipalmitoylphosphatidylcholine bilayer and sarcoplasmic-reticulum
membrane. The results indicated that the ultrasonic measurements are very sensitive to the co-operative transition in lipid
bilayers as well as the relaxation of biological membranes containing intrinsic proteins.
Paper presented at the ?Meeting on Lyotropics and Related Fields?, held in Rende, Cosenza, September 13–18, 1982. 相似文献
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Mikio Hori Tadashi Kataoka Hiroshi Shimizu Kiminori Tomimatsu 《Tetrahedron letters》1982,23(8):901-904
The isolates cis- and trans-9phenylselenoxanthene-N-arylsulfonylselenilimines were not interconverted thermally. cis-Isomers were converted to trans-isomers by chloramine-T or -B in a fashion of SN2 type substitution. cis-Isomers did not rearrange but trans-isomers rearranged thermally to 9-arylsulfonamido-9-phenylselenoxanthenes, whereas both isomers underwent the base-catalyzed intermolecular rearrangement. 相似文献
110.
Non-stereospecific ring expansions of 3-acetylbenzothiazoline sulfoxides to benzothiazines from the reaction with acetic anhydride are reported. 相似文献