From the viewpoint of the temperature conductivity and the temperature uniformity, some heat and seal cutter for making bags is inserted a heat pipe in the horizontal direction. However, the effect of the heat pipe is on the heat and temperature characteristics of heat and seal cutter is not always clear. In this study, the heat and temperature characteristics of the heat and seal cutter that the heat pipe was inserted were investigated. As a result, the temperature recovery characteristics of the heat and seal cutter with the heat pipe were found to be better than that without the heat pipe.

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　　　In a previous study, the heat transfer enhancement of a drag-reducing surfactant solution flow mixed with fine bubbles was considered. The diameter of the fine bubbles was 100 μm or more. However, the flow characteristics of a flow mixed with even finer bubbles like microbubbles are unclear. This paper describes the flow and heat transfer characteristics of a drag-reducing surfactant solution-microbubble two-phase virtical flow. Microbubbles were generated in two ways for air injection in this experiment: mixing air through a porous metal and using a high-speed swirling flow-type generator. The volumetric flow rates of the microbubbles were 0.3% and 0.5%. In the experimental results, the diameter of the microbubbles generated with the swirling flow-type generator was about 70 μm regardless of the Reynolds number. With the surfactant solution-microbubble two-phase flow, the pipe friction factor was increased and the heat transfer coefficient was enhanced compared with the single-phase flow. The heat transfer enhancement of the drag reducing flow increased with the smaller microbubble diameter. The experimental results indicate that microbubble injection into the surfactant solution affects the micelle structure in the solution.

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　　　Aiming to develop simple strategies for the uniform droplet production, experimental investigations were made on the breakup of laminar liquid-jet injected downward into the atmosphere from a cylindrical nozzle which was oscillated sinusoidally. The breakup manner, the breakup time and the size distribution of generated droplets were examined for the cases of vertical, lateral and oblique oscillations. The inner diameter of nozzle was 0.9mm. The liquid-injection velocity was ranging mainly from 0.5 to 1.5m/s - the laminar jet regime, the frequency range of oscillation was 100-800Hz, and the amplitude range was 0.5-5μm. Detailed investigations were performed employing ethanol as test liquid, first. When the nozzle was oscillated obliquely, the liquid jet broke up rapidly in synchronization with the oscillation within the frequency range from the axisymmetric Rayleigh mode to the twice. The outstanding satellite droplets were seldom found and the size distribution of generated droplets was almost close to a mono- dispersed state, although the amplitude of oscillation was invisibly small. Experimental investigations were also performed employing water and 60wt% aqua-solution of propylene-glycol. Finally, it was found that the oblique oscillation of liquid-injection nozzle was suitable for the periodic breakup and the uniform droplet generation.

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　　　The stress measurement method using the fractal analysis of grown grains which occur in an electrodeposited copper foil was examined in this report. The electrodeposited copper foil was adhered to the titanium specimen and cyclic loading test was carried out under bending or torsion condition. Fractal property was observed in the microphotograph of grown grains which occurred by various repeated loading conditions and it became clear that the fractal dimension calculated by the box-counting method depends on the maximum shear stress and a number of cycles. The expression among maximum shearing stress, number of cycles and fractal dimension was proposed based on the experimental results. The combination of this expression and the traditional formula related to the grown grain density enables us to estimate the maximum shearing stress even if the number of cycles is unknown. Moreover, a unique relation was recognized between the grown grain density and the fractal dimension. This means that the fractal dimension can be estimated from the grown grain density. This result suggests that the maximum shearing stress can be obtained only by measuring the grown grain density.

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