It has been proposed that Pu-238 be produced by irradiating neptunium solution in one or more loops in a reactor and then recovering the Pu-238 in a close-coupled separations plant. Such a scheme could replace the more conventional scheme of solid element fabrication, irradiation, and reprocessing for plutonium and neptunium recovery. This document presents the advantages of such a scheme from the standpoint of product purity and Pu-238 production.

The variations of size and density of aerosol particles were examined. Experiments were made with a wide variety of substances using a modification of Whytlaw-Gray and Patterson's methods in which freefall velocity was determined. The mass was estimated both by balancing the gravitational and electrostatic forces and from rising velocities under constant field strength. The results were compared with the shape and structure of the aerosols shown by electron microscopy. The variation of the Stokes' (or drag) diameters was found by combining the results with cascadeimpactor and microscope measurements. A modification of the Millikan oil drop apparatus was used. It was concluded that the free-fall velocity of an agglomerate is proportional to the two-thirds power of its mass, and when primary particles are not uniform in size and shape, wide variation in agglomerate densities occur. It was also noted that when primary particles have irregular shapes there is a difference in drag diameter of the agglomerate determined from the rising and falling velocities. This is a factor in electrical precipitation of such aerosols. (J.R.D.)

Methods are presented for the analysis of 41 refractory materials. An evaluation of the accuracy and the precision of these techniques are also given The materials studied are the borides of hafnium, molybdenum, niobiumL rhenium, tantalum, thorium, titanium, tungsten, uranium vanadium, and zirconium; the carbides of hafnium molybdenum, miobium, silicon, tantalum, thorium, titanium, tungsten, uranium, vanadium, and zircomium; the nitrides of boron, hafnium, niobium, silicon, tantalum, titanium, uranium, and zirconium; the silicides of molybdenum, rhenium, tantalum, titanium, tungsten, vanadium, and zirconium; and mixed carbides of uranium with hafnium, niobium, tantalum, or zirconium. (auth)

Tables of numerical values of all necessary functions and instructions on their use in the stress analysis of circular plates which have a linear thickness-radius relationship, and which are loaded axisymmetrically, are presented. The analysis is based on the classical smalldeflection theory. Emphasis is placed on plates whose thickness at the inner radius is greater than the thickness at the outer radius. However, a limited number of plates for which the opposite is true may also be analyzed by the procedure presented. The limitations on the dimensions of the latter type of plate are explained. (auth)

I. An adequate and conservative calculational method for evaluation of the heat generation distribution in the primary sodium system substructural areas was developed. The method was programed for the IBM 704 and the IBM 709. The results obtained from analysis of the gamma heat generation in the primary sodium pipe tunnels and in the intermediate heat exchanger cells are presented. Calculations are outlined, and gamma attenuation coefficients for concrete, sodium, and steel are given. II. Results obtained from analysis of the gamma heat generation in areas where the primary sodium system piping layout was changed from that of the previous analysis are presented. Major changes in magnitude of the hot spot heat generation due to the changes are pointed out. (auth)

Information relative to the performance and operation of silver reactors is presented. The information is given as answers to questions submitted in the USAECEurochemic Company cooperative program. The answers to 8 questions are presented along with the basis for comments. (J.R.D.)

Equipment and techniques for high-pressure high temperature solid-state studies were developed, and some preliminary results for the reaction of uranium oxides with other oxidcs were obtaincd. A new die design was evolved which appears suitable for any work currently contemplated. The maximum capabilities of this new die are as yet undetermined, but its theoretical pressure limit is in excess of 200,000 atm. The die differs from similar equipment in that internal heating of the sample is employed and maximum pressure and temperature can be maintained simultaneously. Most of the preliminary work on materials synthesis was performed at pressures up to 40,000 atm. and temperatures to 1000 deg C. No reactions were found in the system UO/sub 2/ and U/sub 3/O/sub 8/ with BeO while under pressure. However, a reaction between Sc/sub 2/O/sub 3/ was detected which was not detected at normal pressure. Sc/sub 2/O/sub 3/ reacted with U/sub 3/O/ sub 8/ under pressure as it does at ambient pressure. A new high-pressure high- temperature phase of U/sub 3/O/sub 8/ was produced. Preliminary study of the U/ sub 3/O/sub 8/ pressuretemperature phase diagram was made. The crystal structure of the new U/ sub 3/O/sub 8/ phase has not yet been determined. …

This program, using the lBM 650 electronic data processing machine, is used primarily as a tool in order to prepare input data for an lBM 704 code ATBAC. The code calculates steady state thermal characteris tics of a plate type fuel element for both a nominal and adverse chanael. (auth)

A method was developed for using an IBM-650 data processing machine to obtain detailed information concerning thermal and hydraulic conditions within a platetype reactor channel when the coolant in the channel is present in both vapor and liquid phases. (auth)

A simplified model for solids deposition in the pot calcination of waste was analyzed, and numerical calculations were made. In long calcination pots of 10 to 12 in. diameter, calcination times should not exceed 24 hours and might be as low as three hours if the pot is kept full. If the pots are fed at a constant rate, the cake might form with a steady state V'' when viewed in vertical section which would progress from bottom to top. Cake deposition rates appear to be independent of pot radius. Several advantages to using larger diameter pots are discussed. (auth)

Studies were made to determine the actual surface temperature of OMRE fuel elements if the thermocouple were not present. Chromel-alumel thermocouples are being attached to the fuel plate cladding of Type 304 stainless steel. These wires are in contact with the coolant stream. Heat transfer from the thermocouple junction, by conduction along the lead-wires and by forced convection to the coolant, produces a lowering of the surface temperature in the region of the junction which results in an error in surface temperature measurement. (W.L.H.)

Fluoride Volatilization Separations Process. Work has continued on the development of fluoride volatilization processes for recovery of U and Pu from spent power-reactor fuels. Results are reported on the fluorination rates of U and Pu oxides and fluorides. The conversion rate of UO/sub 2/F/sub 2/ to UF/sub 6/ by elemental fluorine was determined as a function of temperature. Uranium trioxide is fiuorinated at a slower rate than the other U compounds investigated. On exposure to fluorine PuO/sub 2/ appears to form the PuF/sub 4/, which, in turn, is converted to PuF/sub 6/. The product of the thermal deconmposition ofPuF/sub 6/ is PuF/sub 4/. The fluorination of Ni at 600 to 800 C produces films of a higher density than that of crystalline NiF/sub 2/. Flourination studies on Ti, Pt, Au, and Ag indicated that none of these netals is suitable for use with fluorine at temperatures much above 100 C. Development work continued on a high-temperature fusedsalt process for the recovery of enriched U from Zrdissolver-hydrofluornator made of graphite is nearly Reactor (LMFR) core fluid by a floride volatility process is being investigated. Fluidization Studies. Investigaition of the effect of process variables on the fluidion steps of the ADF d …

This report for February 1959, from the Chemical Processing Department at HAPO, discusses the following: Production operation; Purex and Redox operation; Finished products operation; maintenance: Financial operations; facilities engineering; research; and employee relations.

In order to establish the feasibility of using two colorimetric met;iods for the determination of uranium interchangeably, according to the interferences encountered in a particular sampte. results were obtained by each of the methods and compared. The dibenzoyl methane method and the ethyl acetate-ammonium thiocyanate procedure were compared on the basis of values secured on the same day. on different days, on an analysis of the variance. and on an analysis of the residual error for the methods on different days. On the basis of the findings of these tests. it is concluded that the two methods can be used interchangeably to determine the uranium content of the ethyl acetate extracts of samples. Since the interferences in the two methods are different. the uranium content of a variety of materials can be determined without additional separations being required. (auth)

Experimental extrusions were prepared from mixtures of atomized aluminum alloy and several powdered additives, including SiO/sub 2/, AlPO/sub 4/, and Al/ sub 2/O/sub 3/. Some of the extrusions failed during corrosion testing in water at 290 and 350 C. Others corroded in approximately the same fashion as wrought X8001 alloy. The ultimate tensile strengths of these extrusions at 316 C were approximately two and one-half times greater than that of wrought X8001 alloy. (auth)

Data on critical assemblies of fissionable uranium metals are summarized. Empirical studies are made for spccific reflectors and gcometrics to determine the fcasibility of extrapolating these data for conditions concerning nuclcear safcty problems. Also included are the influencs on critical systems by various reficctors, U-235 isotopic enrichment, density, and small metal pieces homogcncously distributed in water. (auth)

Dimensions for the circular fuel element which allow for thermal growth, swelling due to irradiation, and estimates for practical manufacturing tolerances are determined. (W.L.H.)

The objective of this test is to determine the quality and erosion resistance of cape and cans produced from cast X-8001 alloy blanks through fabrication and irradiation of limited quantities in accordance with the testing procedure herein defined. Components which were fabricated from X-8001 alloy cast blanks have been subjected to rigorous out-of-reactor tests and have indicated equivalence or possible superiority to standard X-8001 alloy components. It is, therefore, proposed that; (1) six enriched charges of (0.94% U235) test material alternated with standard control material be irradiated; two to 500 MWD/T, and four to 800 MWD/T goal exposures in an old reactor, to compare corrosion resistance and (2) up to 240 charges of test enriched fuel elements be irradiated to normal variable goal exposure for enriched I&E in the same reactor, to further evaluate the performance of the components fabricated from cast blanks.

The casting procedures, mechanical working characteristics, composite fuel plate fabrication, and fuel element assembly methods for a nominal 48 wt.% U- 3 wt.% Si -AP alloy are examined. It was found that localized clad thinning, resulting from dogboning'' of the fuel alloy, is essentially eliminated in composite Plates when this alloy is used in combination with 5154 Al frames and 1100 Al covers. However, fuel component dimensions are difficult to maintain within commonly accepted tolersnces in the brazing prccess because of the marked differences in the thermal expansion of the fuel alloy and the containment materials. The mechanical properties, irradiation studies, corrosfon testing, pneumatic pressure testing, and chemical reprocessing of the Si-modified alloy are also discussed. (auth)

Data on the effects of nuclear fuel burnup on dissolution rates and U losses of a few fuel types are summarized. Burnup to the 40% level produced very little effect on the rate of solution of stainless steel-UO/sub 2/ fuel elements in solutions of the Darex type. Beyond passivation, burnup to the 250 Mwd/T level did not produce a large effect on the rate of decladding nor on the U losses in the Sulfex process. Bunnup to the 15% or 4300 Mwd/T level produced little or no effect on the rate of decladding, U losses, or Pu losses in the Zirflex process. Two other effects, air oxidation of irradiated UO/sub 2/ and prolonged contact of this oxide with Sulfex solutions in the absence of actively dissolving stainless steel appeared to be much more serious sources of loss of U. (auth)

Data are presented from a study of the effects of indoleacetic acid and kinetin on the growth of Amoeba proteus, Escherichia coli, and two species of yeast. Data are tabulated and reaction mechanisms are discussed. 95 references. (C.H.)

None

An estimate was made of the fast effect in the lid tank source plate. The number of fast fissions per thermal fission is 0.019. (auth)

Information related to the performance and operation of the Idaho Chemical Processing Plant is presented. The information is presented as answers to questions posed for Eurochemic assistance program. (J.R.D.)