To investigate the relationship between the pseudogap and superconductivity, we measured both the in-plane (ρ ab ) and out-of-plane (ρ c ) resistivity for oxygen-controlled Bi 2 Sr 2 CaCu 2 O 8+δ single crystals subject to magnetic fields (parallel to the c axis) of up to 17.5 T. The onset temperature for the superconductive fluctuation, T sc f , is determined by the large positive in-plane magnetoresistance (MR) and negative out-of-plane MR observed near T c , whereas the pseudogap opening temperature T * is determined by the semiconductive upturn of the zero-field ρ c . T sc f was found to scale roughly as T c , with a decreasing temperature interval between them upon doping. On the other hand, T * starts out much higher than T sc f but decreases monotonically upon doping; finally, at a heavily overdoped state, it is not observed above T sc f . These results imply that the pseudogap is not a simple precursor of superconductivity, but that further study is needed to determine whether or not T * exists below T sc f in the heavily overdoped state.

Cold model experiments were conducted to investigate the dripping behavior of molten iron in the coke packed bed filled with molten slag. The dripping behavior or dripping rate of pseudo-iron droplets in packed beds filled with immiscible liquid was described well by three comparatively simple mathematical models. KEY WORDS: iron and slag flow; immiscible liquid; blast furnace hearth; ironmaking; packed coke bed. Fig. 1. Schematic diagram of experimental apparatus.

Coarse-grained picture of Brownian motion in water: Role of size and interaction distance range on the nature of randomness

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Measurement of flexoelectric coefficients has been oneof the most difficult research subjects of liquid crystals (LCs). As described in the first literature published by R. B. Mayer 1) , flexoelectric polarization is emerged by orientational deformation called splay and bend 2) . Like piezoelectric polarization in crystals, flexoelectric polarization had seemed to be easily measurable bulk polarization. Up to today, various measurement methods have been proposed. For example, T. Takahashi et al. 3) and S. A. Jewell et al. 4) separately reported experimental measurement results of flexoelectric coefficients based on their original optical methods, where the obtained the sum of the splay and bend flexoelectric coefficients (e p = e11 + e33) were the order of 10 -11 C/m. However, it is known that even measurement results for de facto standard LC material such as 5CB (4'-pentyl-4biphenylcarbonitrile), reported flexoelectric coefficients obtained by different past measurement methods have not coincide its sign, to say nothing of its values 2) . There seems to be two major causes; one is that the induced polarization is sealed by ionic impurities. The other is due to the indirect electro-optical measurement induced by the inverse flexoelectric effect. With regard to the former cause, there are some reports that the flexoelectric coefficients can be measured by avoiding the influence of impurities contained in the liquid crystal 5,6) .Solving the latter cause is inherently more complicated.Because, in general, flexoelectric coefficients is indirectly estimated through the electro-optical response due to the change of LC director distribution throughout the LC cell, which is seriously affected not only by flexoelectric effect but also by interfacial factors such as surface anchoring energy and pretilt angle. In other words, flexoelectric coefficients can be estimated by a numerical simulation based on the continuum theory that also considered the surface anchoring effect. That is, in order to discuss the correctness of the estimation of flexoelectric coefficients, it is necessary to reexamine surface anchoring energy and pretilt angle at the orientational surface as well as bulk physical parameters such as dielectric constant and elastic constant.Previously, our group demonstrated unique measurement method to determine surface anchoring energy, pretilt angle, dielectric anisotropy and reduced elastic constant simultaneously by means of the symmetric oblique incident transmission ellipsometry (SOITE) 7, 8) . As an application of SOITE method, we also tried to estimate the flexoelectric coefficients 9, 10) . However, it seemed that the expected accuracy and reproducibility have not been obtained so far because of Abstract Improvement of the flexoelectric coefficients estimating procedure by means of the transmission phase difference measurement was demonstrated. It was found that the sign of the sum of two flexoelectric coefficients for splay and bend deformation can be determined from the DC applied voltage dependence cu...

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Synopsis :Cold model experiments were conducted to investigate the dripping behavior of molten iron in the coke packed bed filled with molten slag.The dripping behavior or dripping rate of pseudo-iron droplets in packed beds filled with immiscible liquid was described well by three comparatively simple mathematical models. Key words : iron and slag flow; immiscible liquid; blast furnace hearth; ironmaking; packed coke bed.