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The phase separation temperatures of dilute solutions of 4He in liquid 3He in the Fermi-liquid region have been measured by detecting the 4He film formation sensitively. From the obtained solubility curve, the effective mass of 4He atom and the difference in binding energy of 4He in liquid 4He and in liquid 3He are proposed.

Boiling behavior of liquid 3He below 1 K was visualized as shadowgraph image. A light source and a video camera (or still camera) were arranged at room temperature. The light was guided to the 3He cell by an optical fiber, and the shadowgraph image was transferred to the camera by an image fiber. The 3He bubble formed on the heated copper surface was spheroid-like due to the low surface tension. The size at departure from the surface and the relative bubble formation rate were measured as a function of heat flux. The previously obtained heat transfer curve could be explained qualitatively by this boiling behavior.

Polymerization of MMA with R3P-R3′Al in toluene at low temperatures was reinvestigated and was found to give highly syndiotactic PMMA. Among the initiators examined Ph3P-Et3Al gave the PMMA with highest syndiotacticity and the polymerization at −93°C yielded PMMA with rr content of 95%. PMMAs prepared with Et3P-Et3Al and Ph3P-Et3Al contained the structural unit comprised of the phosphine components at the chain end as evidenced by 31P and 1H NMR analyses. The results clearly indicate that R3P takes an important role in the initiation process, though R3P alone does not polymerize MMA. Methacrylic acid esters of primary and secondary alcohols were also polymerized by these initiators to give highly syndiotactic polymers. Block and random copolymers of MMA with several methacrylates were also obtained. The effect of syndiotacticity on the glass transition temperature (Tg) of PMMA was examined and Tg for 100% syndiotactic PMMA with infinite molecular weight was estimated to be 141°C.

The depinning temperatures in YBa2Cu3O7−δ ceramics and grains have been studied at magnetic field up to 4 T and various amplitudes of vibration. For ceramics sample, large amplitude dependence of depinning temperature TD was observed, which indicate the decoupling of grains. In the case of a suspension sample (grain), TD was much lower than that of ceramics.