From abstract: "Data obtained in laboratory studies of the 'fumelses dissolving' of irradiated uranium are presented. Procedures for handling dissolver off-gases are proposed."

Second and third tests were conducted on an expansion bellows and Zircaloy-stainless steel transition joint assembly, duplicating that used in the core-pressure vessel assembly of the HRT. The assembly was exposed for 1140 hours in the second test and and 167 hours in the third to a solution containing 0.04m UO2SO4, 0.02m H2SO4, and 0.005m CuSO4 in a 100A dynamic corrosion loop under conditions simulating reactor startup, shutdown, and steady-state operation. Results indicated that the transition joint assembly as tested was mechanically sound and leak-tight. Pit-type corrosion continued on the expansion bellows where the upper retaining tangent contacts the bellows. Results are included of specimens exposed to the circulation solution during transition joint and bellows test.

A third test of the mockup of the Zircaloy - stainless steel transition joint as used in the HRT reactor vessel was completed. No additional mechanical deflections of the bellows were made, but 12 additional thermal cycles of the unit were carried out. . The joint and bellows functioned properly and were leak-tight. Corrosion of stainless steel in 0.04 m UO2SO4 containing equimolar beryllium sulfate was not greater at 10-15 fps and much less at 15-75 fps, than in HRT solution at 200 and 225 C. Increasing the beryllium sulfate concentration to 0.08 m increased corrosion at 225 C and resulted in an unstable solution at 300 C.

Data are presented for all toroid runs which circulated aqueous thorium oxide slurries between Aug, 1054, and October, 1956. In addition, a tabulation of the properties of numerous thoria preparations is presented.

The distillation method (Argonne Sampler) for the analysis of sodium oxide in NaK was used to calibrate a plug indicator. The description of the equipment, procedure, and experiences with the Argonne Samplers are presented in great detail to aid future users of this method. Although this method is not very precise, it has been thoroughly checked out and is recommended as a standard means for sampling and analysis for oxide in liquid metal systems. (auth)

The assembly of a second thorium oxide slurry corrosion test facility, loop BS, has been completed and 2010 hr of operation on slurry have been logged. This second test loop has proved satisfactory from an .operational standpoint. Corrosion data and operational observations are given for six thorium oxide slurry runs made at 300 C in 100A pump loops BS and CS. A new development model of the rotator for an in-pile slurry toroid is described.