Introduction: "This is the ninth letter report on ARF Project C 127, entitled "Preliminary Studies of Scavenging Systems Related to Radioactive Fallout." This report covers the period from August 1 to October 1, 1959."

Judging scratch depth or surface roughness by unaided visual inspection under controlled conditions, while rapid and popular, is not quantitative. Comparison methods improve reproducibility but are generally not applicable to evaluation of depths of single widely spaced scratches. Stylus-type contour recorders yield valuable scratch contour data but may themselves plow through soft materials and fine details. Depth measuring microscopes are particularly applicable to measurement of pinhole depth but do not graphically reveal profiles and provide only a small field of view. The comparatively large field of view and graphic display of contour provided by profile microscopes make them particularly suitable for evaluation scratch depth as well as surface roughness. A HAPO-constructed instrument has demonstrated an accuracy of +/- 50 micro inches in the range of 50 to 15,000 micro-inches scratch depth. It is a pocket-sized, portable, and can be used on horizontal and vertical surfaces by untrained persons with only brief instruction.

The monocarbide and the mononitride of uranium are potentially useful ceramic nuclear fuel materials. This paper reports the results of exploratory investigations of the reactions of uranium monocarbide and uranium mononitride with boiling water. Uranium dioxide, chemically stable in deoxygenated boiling water, was used as a control.

Designing a dissolver safe for up to 5 per cent U.235 enriched NPF's and having a one a ton per day capacity is a fundamental problem of Hanford NPF Program. Two basic design concepts have so far evolved, both of which employ a recirculating system in which the fuel elements are placed in the critically safe geometry separated from the bulk of the solution in another vessel. In one concept the fuel elements are charged to a set of geometrically safe cylinders or tubes and solution is circulated through them/ In the other concept the fuel elements are placed on a flat tray while solution is sprayed over them. In the latter system, nuclear safety is obtained by avoiding submerged dissolution and the resulting neutron moderation by the solution.

Results of four experiemental runs in the Fluorox fluidized bed reactor system are reported. The engineering feasibility of UF6 production from UF4 by use of dry air of O2, 2UF4 + O2 = UF6 + UO2F2, in an Inconel fluidized bed reactor at 800-850°C was demonstrated in two experimental tests in which greater than 90% of the theoretical amount of UF6 was collected or measured. Two runs made with crude UF4 (produced from unpurified mill concentrate) as the feed material, showed that UF6 could be produced at 700-725°C but corrosion on Inconel was prohibitive.

At the present time, plants in the 100-500Mv size range are more numerous and carry the greatest portion (over 50%) of the total steam-electric plant load in the U.S. utilities industry. The contribution of plants of over 1,000-Mv capacity is increasing more rapidly than any other size clarification and at present represents about 10% of the total capacity. By 1962 the TVA will have six plants with capacities of over 1,000-Mv. The largest steam-electric plant in the U.S. is the TVA plant at Kingston, Tenn., with a nameplate capacity of 1,440-Mv. Turbine-generator units are also following a trend of ever-increasing size. In present construction, the 150-200 Mv size range for units is the most common and represents the greatest contribution to capacity. Two units of 500-Mv nameplate rating each, the largest in the U.S., are on order by the TVA, and an 800 Mv unit is contemplated.

Data obtained in test of Bureau of Mines electrocerium are presented. The cerium was subjected to spectrochemical analysis, x-ray diffraction analysis, thermal analysis, metallographic tests, and high-pressure experiments.