Thermal stress failure of square type surface mount device (SMD) such as ceramic capacitor has been evaluated in surface mounting process on metal base printed wiring board (PWB). For the evaluation, a series of transient thermal stress analyses with FEM model and thermal stress failure experiments for the surface mount assembly were carried out with complementary relation. As a result, thermal stress failure probability of the capacitor is estimated by utilizing the distribution function of three-point bending strength and the maximum value of major principal stress in the vicinity of failure initiation point. Additionally, influence of deformation properties of solder and insulation layer, which is formed on the surface of the PWB, on the failure probability is also evaluated quantitatively by introducing two parameters E_tg and σ_ys. E_tg is related to glass transition temperature and Young's modulus of the layer and σ_ys indicates yield stress of the solder at ambient temperature. Consequently, the present evaluation has led us to appropriate choice of the solder and the layer in order to prevent the capacitor from the thermal stress failure in the surface mounting process of square type SMD on metal base PWB.

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An experimental study on enhancement of nucleate pool boiling heat tranfer by placing a sponge metal close to a plain heated surface was conducted in order to improve the heat transfer performance of the high temperature generator of absorption chiller/heater. The sponge metal has three dimensional porous mesh framework like sponge.
Boiling curves of water under the atmospheric pressure were compared with those of lithium bromide aqueous solution of mass concentration 55 to 58%. Heat transfer characteristics were improved by 2 to3 times both for water and lithium bromide aqueous solution when the sponge metal was placed on the heated surface with and without cleareance.
Three kinds of sponge metals were used for lithium bromide aqueous solution under the reduced pressure (24 kPa). At lower heat fluxes,#6 sponge metal which has the finest mesh and the lowest porosity shows excellent results. At high heat fluxes, however,it causes deterioration of heat transfer. Over the wide range of heat fluxes,# 4 sponge metal was found to be most suitable and the optimal clearence was determined as 0.5 mm.
The sponge metal is of good practical use as a device to enhance the boiling, since no special manufacturing is required for placing it on the heated surface.

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NiO/Y₂O₃-stabilized ZrO₂ (YSZ) composite particles for solid oxide fuel cell (SOFC) anode was fabricated by an advanced mechanical method using an attrition type particle composing machine in dry ambient. In this study, two sets of composite particles with different mixing time were prepared. Structure of the composite particles was markedly influenced by the mixing time since the morphology of the resultant Ni/YSZ cermet anode changed with the mixing time. Then, the relationship between the structure of composite particles and the properties of the Ni/YSZ cermet anode were examined. When the composite particles processed with mixing time of 5min were used, the cermet anode showed lower electrical performance at both 800°C and 1000°C. On the other hand, the longer processed composite particles (30min) resulted in higher electrical performance. The difference of anode performances was explained by the change in cermet morphology associated with the mechanical processing time. These results suggested that the mechanical processing for NiO/YSZ composite particles significantly influenced SOFC anode performance.

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　To elucidate the physico-chemical properties of the juice and the fruit as a whole for pomegranates harvested in the Yamanashi prefecture in Japan compared to that of the imported ones, following analysis were conducted. ① On average, the domestic fruit weight was approximately 150g per fruit, while the aril and juice ratios to the fruit weight were about 60% and 42%, respectively. The juice ratio to the aril weight was approximately 70%. These ratios were lower than those calculated for the imported fruit (approximately 400g per fruit), and not dependent on the fruit size. ② The brix measurement of pomegranate juice from domestic fruit was 17 and the sugar was glucose and fructose, while both ratios were nearly equivalent, it was slightly high in fructose. The same results were obtained for imported fruits. Titratable acidity in the imported fruit was much higher than that in the domestic fruit, which mainly composed of 0.7% oxalic acid. However the organic acid content in the imported fruit was 1.5% citric acid with a small amount of malic acid. ③ The dominant free-amino acids in the juices listed in order of high to low concentration were glutamine, glutamic acid, aspartic acid and serine. There were no significant differences between the juices from domestic And the imported fruit. Small quantities of sarcosine were detected in both juices. ④ Total polyphenol content in the juices was approximately 100mg% and 200mg% in the domestic and imported fruit, respectively. The HPLC analysis of the polyphenol revealed that punicalin and punicalagin were detected in the juices from the domestic fruit and not the imported fruit.

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