The major portion of this paper is devoted to a discussion of the design, ' fabrication, and post-operative tests and inspections of the 2000 kw Sodium Test b Facility which was constructed and operated at the Los Alamos Scientific Laboratory. Of special interest are (1) post-operative inspection of heat exchanger tubing, (2) the investigation of a rupture in a thermocouple well, and (3) the investigation of the thermal stress fatigue cracking of a pipe tee and adjacent piping. Discussed briefly are (1) operating experience with 17-4 PH stainless steel in the LAMPRE sodium system and (2) the results of corrosion tests of tantalum in cold-trapped and hot-trapped sodium .

By combining arc casting and electron beam melting, spectroscopically pure tantalum and alloys, suitable for containment of molten Pu-Fe alloys, were producedo The 0. 1% W alloy was used for the first LAMPRE loading.The effects of a large number of additives on the corrosion resistance of tantalum were tested^ Additions of up to 10% tungsten gave increasing endurance« Specimens of tantalum irradiated with neutrons until 3% converted to tungsten were still satisfactory in mechanical properties for reactor use.Either tungsten or the traces of yttrium remaining after arc melting can raise the one-hour recrystallization temperature of tantalum by 400'C, Effects of internal strain, critical strain and precipitation hardening in tantalum alloys were studied., High-temperature annealed tantalum had superior corrosion resistance, while impact extruded and ironed material was better than deep-drawn metal. Mechanical tests on tantalum with added interstitial elements showed that their presence to the extent expected in LAMPRE would be unlikely to weaken the tantalum. Evidence was found that oxygen promotes plutonium attack on tantalum. Small amounts of hydrogen, nitrogen and carbon had no effect on corrosion.

A kinetic study has been made to determine the optimum conditions for the palladiumcatalyzed hydrogenations of dinitrotoluene to toluenediamine and of rn-dinitrobenzene to m-phenylenediamine. The rate-determining step under the recommended conditions is the diffusion of hydrogen. The reaction rate is zero-order with respect to the nitro compound and first-order with respect t o the pressure of hydrogen. It increases, but not linearly, with increasing catalyst concentration, has a low temperature coefficient, and i s markedly dependent on the efficiency of agitation. Suitable solvents are alcohols and aromatic hydrocarbons.

No abstract

No abstract