The ORIC (Oak Ridge Relativistic Isochronous Cyclotron) radiofrequency system for which Model III represents the resonator is the third system which has received enough consideration to warrant construction of a model. The purpose of the model is to check the calculations for the frequency range and excitation power of the resonator. After an introductory description of the r-f system and model, the detailed calculations of the properties of the model will be given followed by the data from measurements of the model characteristics.

The feasibility of using electroless nickel, a chemical deposit containing about 10 wt% phosphorous in nickel, as the brazing alloy for assembling tubular stainless steel fuel elements of the type specified in Core I of the N. S. Savannah was investigated. This material was nelected primarily because of the case of braze-metal preplacement by chemical deposition of the alloy on type 304 stainless steel ferrule spacers, prior to fuel-bundle assembly. Brazed joints produced by this method were generally characterized by a relatively ductile solid-solution region at the thinnest portions of the fillet. This ductile zone should minimize the possibility of complete propagation of hairline cracks, which form in the brittle, eutectic regions of fillet.

By using a large central fuel and blanket reprocessing facility, slurry-fueled aqueous homogeneous reactors can attain an estimated minimum fuel cycle cost of 1.4-1.6 mills/kwh; with solution-fueled two-region reactors, a doubling time of 14 years may be obtained at a fuel cycle cost of 2.0 mills/kwh. On-site processing appears desirable only for large power stations made up of reactors designed for short doubling times. For instance, a solution-fueled two-region reactor can attain a 12-year doubling time at an estimated fuel cycle cost of 1.5 mills/kwh at a 2000 Mw electricity station with an on-site processing plant.

A method was developed for the spectrophotometric determination of 30 to 100 ug of osmium as OSO4 is extracted with CHCl3 and diphenylcarbazide is then added to the organic extract. A blue-violet reaction product is formed, the absorbancy of which is measured at 560 mu. A suitable reagent concentration is from 3 to 5 ml of 0.2% diphenylcarbazide in a volume of 25 ml and the preferred solvent for the reagent is ethanol. Beer's law is followed over a range of 8 to 130 ug of osmium with a coefficient of variation of about 4%. After a 2-hour color-development period the molar absorbancy in less than 2 hours were unsuccessful. A study was made of the effects of foreign elements and only Ru(VIII) was found to interfere.

The 300A and loop were operated for 2862 hr with thorium oxide slurry at 1500 psi and 280ºC to determine the effects vane inlet and exit geometries on impeller wear, the wear rate of aluminum oxide bearings in this size pump, and the operating characteristics of the loop. The thoris, a 1600*C-fired oxide, had a mean particle size of approximately 2 u. Average circulating slurry concentration was approximately 450 grams of thorium per kilogram of water and average flow rate was approximately 300 gpm.