Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1993: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1992: ¥1,600,000 (Direct Cost: ¥1,600,000)
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Research Abstract |
Behaviors of conduction electrons were investigated near the critical point of two liquid phase separation in liquid Bi-Ga alloys. The resistivity, rho, of liquid Bi-Ga alloys decreases moderately with the decrease of temperature, T,far above the ctitical temperature, T_c. However, with the approach to T_c the rho decreases abruptly particularly in the supercooling temperature range of homogeneous liquid, that is in the T range below the binodal line. This is considered to reflect the growth of concentration fluctuations up to the onset of the two phase separations. In addition it is to be noted that the T range of this supercooling is minimum at the critical composition X_c and larger around X_c. This indicates that the onset of two phase separations may be initiated by the spinodal decomposition. Based on these experimental facts the rho of liquid Bi-Ga alloys were investigsated under the microgravity, which was realized by the launch of rocket. It was found that under the micrograviuty, the decrease of rho on cooling process begins at 15K higher temperature than the the binodal temperature. This indicates that the microgravity condition is very effective to surpress the convection effects on the growth process of concentration fluctuations and provides the appropriate experimental circumstances for the study of true feature of two liquid phase separations. In addition it was found that the degree of supercooling is far larger under microgravity than under 1 g condition. This also indicates that microgravity conditions are very effective to study the supercooling or non equilibrium properties.
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