TiO₂ and Nb:TiO₂ films with 300 nm-thickness were deposited on quartz glass substrates heated at 110°C by dc magnetron sputtering using reduced TiO_2-x and Nb:TiO_2-x targets with Nb concentrations of 3.7 and 9.5 at.%, and then post-annealed under vacuum at 600°C. In order to measure the thermal diffusivity, Mo/(TiO₂ or Nb:TiO₂)/Mo three-layered films, were prepared on quartz glass substrates. Thermal diffusivity was measured by ‘rear heating/front detection type’ nanosecond thermoreflectance system. As Nb concentration of the films increases, thermal diffusivity of the film decreased from 2.1×10^-6 to 1.2×10^-6 m²s^-1. Mechanism of this decrease is attributed to enhancement of scattering of phonon induced by Nb atoms which is heavier than Ti.

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The rate of freezing bread dough is one of the main correlates that determine whether the dough will sustain damage from freezing. The purpose of this research is to determine the best way to freeze bread dough by defining the effects of freezing on product quality. Internal changes in bread dough following the freezing process were numerically calculated from measurements of the effective thermal conductivities and specific heat.
Bread dough was frozen at a regulated freezing rate, and then it was baked into breads and buns. Measurements were then made of the bore area of the crumb cells, the specific volume, and the hardness of the baked products. Reductions in the freezing rate were associated with a decline in bread quality as evaluated by the internal phase, size, shape, and texture of the baked bread.

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Lowering of the minimum temperature achieved during the process of bread dough freezing decreases the activity of yeast used in bread making. In addition, the devitalized yeast causes secondary destruction of the dough structure due to leakage of reducing substances from the yeasts themselves. The purpose of this research is to determine the best way to freeze bread dough by defining the effects of freezing on product quality. The internal state changes occurring in the dough during the freezing process were estimated by numerical calculations.
Frozen dough subjected to controlled minimum freezing temperatures was baked into breads and buns. The CO2 production during the fermentation process confirmed the deactivation of the yeast. Under conditions where the minimum achieved temperature fell below the deactivation temperature for yeast, declines in bread quality, evaluated as changes in internal phase, size, and shape of the baked product, were observed.

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In this study, in order to use waste heat in middle temperature region (100℃〜250℃) from factories, it is investigated about fundamental melting characteristic of erythritol, mannitol, and their mixtures as phase change materials (PCMs), which are applicable for latent heat thermal energy system. The melting point of erythritol and mannitol, melting peak temperature of their mixtures, and latent heat were measured by differential scanning calorimetry (DSC). The melting behavior of these PCMs put in the test tube was observed by the digital camera. The acquired conclusions are; 1) In the DSC measurement, it was found that at mannitol content from 10 to 40mass% and from 70 to 90mass%, these mixtures have one and two melting peak temperature, respectively, and at mannitol content from 50 to 65mass%, it have three melting peak temperature. 2) In fundamental melting behavior of mixtures, it was confirmed that the melting behavior with repeated solidification and melting process does not change, and the density difference of solid phase and liquid phase affects the melting behavior.

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Flow characteristics of phase change slurries were experimentally investigated. Ice slurry and tetra-n-butyl ammonium bromide (TBAB) hydrate slurry were used as the phase change slurries. Reynolds number, the diameter of the tubes and the solid fraction were varied as the experimental parameters, and the coefficients of pipe friction were calculated from the pressure drop. For low Reynolds number region flow, it was found that the coefficients of pipe friction increased with the solid fraction, and the tendencies of the coefficients of pipe friction were significantly dependent on the solid fraction for high Reynolds number region. Moreover, it was presumed that the phase change slurry can be treated as pseudoplastic fluid, and the laminarization condition was clarified using the apparent Reynolds number. The method to predict the pipe friction coefficients were considered.

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