In this paper, we make a quantum mechanical treatment to Liquid Helium which is considered to boson assembly. By this treatment, we can obtain some thermal qualities of Liquid Helium, and show the possibility of superfluidity.
Dilatomic and pycnometric measurements of unfractionated polystyrene and polyvinylalcohol in liquid and solid states are presented over a certain temperature range and under various conditions. In case of polystyren solutions, the apparent specific volume almost coincides with what is obtained by extrapolating the specific volume of melt polystyrene to the same temperature. In contrast with polystyrene, the apparent specific volume of P.V.A. (in aquous solution) is smaller than the similar corresponding value, and it increases with concentration in comparative wide range. Density and thermal expansion coefficient of P.V.A. in bulk vary by stretching. These facts are explained qualitatively from the nature of molecular interactions. Especially, the transition of P.V.A. is seemed to occur in only amorphous phase. The density and expansion coefficient of P.V.A. crystallites are estimated as 1.36 (at 20°C) and 1.1±0.2×10-4deg-1