Two arrangements of internal components of a freeze seal model were tested in order to determine the hydraulic characteristics. The internal configuration employing cylindrical knitted mesh packings in the connecting pipes proved the most suitable for the Na servicing freeze seal, because these packings are more easily fabricated. (auth)

Progress is reported on the following investigations: separation of Nb and Ta by solvent extraction; separation of Ti and Nb with TBP, and of Hf from Zr with methyl ethyl ketone; preparation of HfF/sub 4/, CeF/sub 3/, LaF/sub 3/, ThCl/ sub 4/, and V chlorides; preparation of Ce, La, V, Nb, anf Hf; phase studies of U- -Zr, U--Ag, U--Nb, V--Al, V--Ta, Th--Mg, Zr - Zn, and Ta alloys; corrosion of high-melting metals and alloys by liquid U-Cr and Mg--Th alloys; casting U into U- Zr alloy cans; coating and electroplating of U; reactions of U with Al-Si alloys at high temperatures; corrosion of U - Zr--Nb alloys in water; crystal structure of sodium tungsten bronze; physical properties of Dy; and phase studies of CaO- CaF/sub 2/ systems. (C.W.H.)