The development of several metallic fuei element systems for air-cooled reactors is reviewed, and the hightemperature properties of Type 310 stainless steel and Nichrome V clad fuel elements are discussed. Early work on cladding of Mo is reviewed, and recent developments in ferrous-base alloys and Cr-base alloys as hightemperature cladding materials are presented. (auth)

The use of self-supported fuel elements in ribless Zircaloy-2 tubes at C-Reactor requires some inlet nozzle modification to allow charging of the larger overall diameter fuel pieces. A new nozzle assembly has been developed (by Equipment Development Operation -- IPD) which will allow use of the new fuel pieces and at the same time increase the reliability of the header-to-tube piping and reduce pumping power losses. Flow test data were requested for the new assembly and the results of these tests are presented herein. This report also presents a comparison of the header to tube energy losses for the various reactor inlet nozzle assemblies which are currently used on the Hanford production reactors.

The synthesis of relatively complex organic molecules by ionizing and radical mechanisms (induced by high energy radiations, ultraviolet and electric discharge) from methane, ammonia, water, and hydrogen is described, both theoretically and experimentally. It is shown that the molecules which tend to be formed under such random conditions are the very ones which today are the common building blocks in the biological reconstruction of organic material. Such molecules are the amino acids, the simple carboxylic and hydroxy acids, purines, pyrimidines, etc. The appearance of order among such random molecules is induced by two forces, namely, autocatalysis and crystallization. The latter is particularly important in the appearance of highly efficient macromolecular structures and arrangements which are so characteristic of present-day living organisms. Points of contact of these theories with experiment are indicated, and where confirmation has been obtained it is described, and the areas of ignorance, requiring further experimentation, are defined. A first step in a possible test of these prebiotic organic syntheses on other astral bodies has been made by examining the organic material found in meteorites. The nature of the structures appearing therein is indicated.

The objective of this production test is to evaluate the behavior during irradiation of nominally 1.739 inch OD., 1.074 inch ID., Zircaloy-2 jacketed single tube fuel elements with brazed end closures at operating conditions somewhat more severe than those expected for N Reactor fuel element outer tubes. Enriched single tube elements with brazed end closures and modified fuel element supports are authorized for irradiation in the KEG loops to an exposure no higher than 4000 MWD/T. A typical loading and set of operating conditions are given; these may be modified, however, by obtaining appropriate approvals.