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The reacting flow fields in reactive miscible viscous fingering in a Hele‐Shaw cell studied by Nagatsu and Ueda had not been completely elucidated, mainly because one cannot exactly recognize where and when the reaction takes place in the reactive fingering pattern. We developed a novel experimental method that allowed us to identify the reaction region in the fingering pattern employed in the previous studies. The novel method involves switching of the less‐viscous liquid injected in both the nonreactive and reactive experiments. By using the novel method, we succeeded in showing how the reaction region in the fingering pattern was affected by the initial reactant concentrations, the Péclet number, and time. We propose physical models of the reacting flow field in the cell's gap direction that can explain the obtained experimental results. © 2009 American Institute of Chemical Engineers AIChE J, 2009  相似文献   
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The levels of 90Sr and 137Cs in human placenta, fetus and diet were determined by radiochemical methods during the period from March 1966 to December 1968. The possible effects of these radionuclides on the pregnant woman and the fetus were discussed. The metabolic characteristics of both 90Sr and 137Cs were also discussed on the basis of estimates of discrimination factors and observed ratios of these radionuclides.

As a result of the analyses, the dose rate to the human placenta resulting from deposition of 90Sr in the organ was estimated at about 0.003 mrem/month and that of 137Cs at about 0.013 mrem/month. The dose rate to the total body resulting from the body burden of these radionuclides in the mother was estimated at about 0.012 mrem/ month. These values are much smaller than the monthly dose from 40K normally existing in the body.

It was rather difficult to draw definitive conclusions concerning the possible correlation between the 90Sr fallout and the annual changes of infant mortality rates in Japan.  相似文献   
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A new architecture with a six-dimensional mesh/torus topology achieves highly scalable and fault-tolerant interconnection networks for large-scale supercomputers that can exceed 10 petaflops.  相似文献   
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Aromatic polyimide film composed of biphenyl tetracarboxylic acid dianhydride (BPDA) and p‐phenylene diamine (PDA) is a very stable polymer at high temperatures and very useful for the electronics industry. Bonding properties were improved by corona discharge treatment of this film. The chemical modification method was applied for generated functional groups, that is, carboxylic, hydroxyl, and amino groups in the gas phase, and the quantity of these functional groups was determined by X‐ray photoelectron spectroscopy. The functional groups increased with corona energy, leveling off at a specific corona energy. The bond strength of the copper foil/adhesive/polyimide film was determined. The relationship between bond strength and functional group content was analyzed by multivariate analysis. Bond strength could be sufficiently correlated with functional group quantity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3403–3408, 2006  相似文献   
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Copolymers containing hydantoin- and imide-groups were prepared using purified materials and applied to the surface of MOSFET (Metal Oxide Semiconductor Field Effect Transistor) in order to amplify the influence of copolymers on semiconductor devices. The influence of the polymers on the residual current of the device was analyzed with respect to impurity content, softening temperature of the polymers, composition ratios etc. It was found that the residual current increases with increasing flowing temperature of the polymer containing only imide groups, and with increasing content of hydantoin groups.  相似文献   
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Abstract— Quick, stable transition from splay‐to‐bend alignment in optically compensated bend (OCB) mode is crucial for practical use. This has been achieved by surface treating part of a pixel with a chiral dopant to induce a twist alignment while controlling the twist direction. The effectiveness of this new method was confirmed in a prototype TFT‐LCD panel.  相似文献   
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The thermal and mechanical behavior of fuel rods is significantly influenced by the extent of their relocation and by compliance of the cracked pellets. Movement of the cracked pellet pieces towards the cladding results in softer pellets with crack voids which accommodate some fraction of the thermoelastic pellet deformation and make the pellet more compliant under the restraint of the cladding. It is difficult to model such a pellet compliance independently of experimental observations because the cracked pellet behavior is uncertain by nature.Electrically heated simulation of pellet-cladding mechanical interaction (PCMI) facilitates much quicker and more flexible experimentation than actual in-pile tests. Testing apparatus consists of the simulated fuel rod with hollow UO2 pellets and a tungsten rod in the center, and a diameter measuring device including three pairs of diameter sensors. Test parameters include the pellet-cladding gap and the cladding thickness. Results show that rods with a smaller gap have a larger increasing rate of cladding diameter. This suggests that a group of cracked pellet pieces induced by thermal stress has an apparent compliance which increases with pellet-cladding gap. Results also show more sensitivity to cladding thickness than those calculated assuming pellets having intrinsic stiffness. This also suggests the compliant nature of cracked pellets.Such a compliant nature can almost be described by reducing the elasticity of the pellet. A simple pellet compliance model was obtained by fitting calculations with measurements to describe a cracked pellet as a uniform axisymmetric body with apparent elasticity.  相似文献   
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