Two thermal conductivity methods, a batch method and a continous flow method have been developed for the measurement of ortho (para) hydrogen concentration. Experimental studies of ortho-para conversion and ortho hydrogen enrichment by selective adsorption and desorption method are discussed.
Some observations of the quantum interference effects associated with Josephson junctions have been carried out. The final aim of this research is the development of a sensitive magnetometer and its application to the measurement of thermal expansion coefficient of metal at low temperatures, for which this is a preliminary study. A device with a periodicity to applied field of about 100μ gauss has been constructed. (This work has been done at physics department in the University of Toronto in Canada.)
Characteristics of superconducting point contact junctions are investigated both theoretically and experimentally. The dependence of the maximum zero-voltage current on contact pressure is measured with Nb-Nb superconducting point contact junctions. The experimental results are qualitatively consistent with those theories which were recently presented by several authors. There are also observed the characteristics which are not satisfactorily explained yet. The usefulness of the superconducting point contact junction as a far-infrared detector is examined theoretically for the future experiment.