The branching ratio of the two modes of decay of Fm'", i.e. , E.C. /n, was found to be about 8.5which gives 89.5% decay by electron capture and 10.5% by alpha emission. It was not possible to measure the cross section for the Cf'"(n, 3n)Fm'" reaction because Fm'" could also be produced from other californium isotopes in the target. A previous publication4 on a possible identification of the Fm'" gave the values of 6.85&0.04 Mev for the alpha-particle energy, and a half-life &10 days. It is a pleasure to thank the crew of the 60-inch cyclotron for their extremely careful and skillful operation of the machine during the bombardment. We wish to thank Professor Glenn T. Seaborg for his continued interest.

No abstract

No abstract

The International Temperature Scale of 1990, ITS-90, came into effect on 1 January 1990, replacing the International Practical Temperature Scale of 1968, IPTS-68, and the "Echelle Provisoire de Température de 1976 entre 0,5 K et 30 K", EPT-76. The present paper reviews the various experimental measurements of thermodynamic temperature T (often expressed as differences (T - T68)) in the range 0,65 K to 1 357,77 K, which were available prior to September 1989, and on the basis of which values of temperature were adopted in the ITS-90. Estimates are given for the uncertainties in the derivation of these values.