Fuel cycle problems of fusion reactors evolve around the breeding, recovery, containment, and recycling of tritium. These processes are described, and their implications and alternatives are discussed. Technically, fuel cycle problems are solvable; economically, their feasibility is not yet known. (auth)

The evolution of this particular blanket concept is described. The geometry of the mirror reactor blanket and the replacement methods that are employed are described. The sub-module design and its thermal-hydraulic considerations, the nuclear model geometry and compositions, and the nuclear calculational method are described. A brief reference is made to calculational vs. experimental results.

The incentive for high density operation of a tokamak reactor was discussed. It is found that high density permits ignition in a relatively small, moderately elongated plasma with a moderate magnetic field strength. Under these conditions, neutron wall loadings approximately 4 MW/m/sup 2/ must be tolerated. The sensitivity analysis with respect to impurity effects shows that impurity control will most likely be necessary to achieve the desired plasma conditions. The charge exchange sputtered impurities are found to have an important effect so that maintaining a low neutral density in the plasma is critical. If it is assumed that neutral beams will be used to heat the plasma to ignition, high energy injection is required (approximately 250 keV) when heating is accompished at full density. A scenario is outlined where the ignition temperature is established at low density and then the fueling rate is increased to attain ignition. This approach may permit beams with energies being developed for use in TFTR to be successfully used to heat a high density device of the type described here to ignition.

A brief outline of existing medical heavy-ion facilities is given. The beam specifications for future dedicated medical ion accelerators are discussed. Machines capable of delivering dose rates of approximately 1 krad/min in volumes of a few liters are shown to represent existing technology. A cost and performance analysis shows the synchrotrons to be the most economical source for the heavier ions while conventional cyclotrons seem optimal for an exclusive proton facility. It is seen that the incorporation of additional capabilities such as neutron generation or radioisotope production can be achieved at modest incremental costs. In addition to the accelerators, feasible layouts of hypothetical facilities are discussed, and three-dimensional beam scanning is shown to allow the irradiation of large volumes without sacrificing the precise dose localization capabilities of heavy-ion beams. Concepts of quality-controlled engineering and modern computer technology are introduced as a means to obtain the desired high degree of reliability and ease of operation and maintenance.

Applications of x-ray photoemission spectroscopy (XPS) to the study of actinide materials are reviewed. Examples discussed here include the band structures of thorium and uranium metal, the multiplet structure associated with the 5f electron states in oxides of the transuranium elements, the test for temporal configurations in NpO/sub 2/, crystal field splitting of the U 6p/sub /sup 3///sub 2// level in a series of uranyl compounds, mixed oxidation states in Cf/sub 7/O/sub 12/, and a test for the participation of 5f electrons in bonding in a series of uranium compounds.

A measurement system for transuranic aerosols has been designed that will be able to withstand the corrosive nature of stack effluents and yet have extremely high sensitivity. It will be capable of measuring 1 maximum permissible concentration (MPC) of plutonium or americium in 30 minutes with a fractional standard deviation of less than 0.33. Background resulting from /sup 218/Po is eliminated by alpha energy discrimination and a decay scheme analysis. A microprocessor controls all data acquisition, data reduction, and instrument calibration.