The indicated methods for determining the following constituents of Diban, which is an aqueous solution of dibasic aluminum nitrate, Al(OH)2NO3, were evaluated statistically: 1aluminum by gravimetric, volumetric, and spectrophotometric procedures, 2. basicity (hydroxyl value) by formation of an aluminum complex and titration of the free acid with standard alkali solution, 3. total nitrogen by the Kjeldahl method, 4. ammonia by the Kjeldahl method, and 5. nitrates by means of a cation-exchange resin and titration of the liberated acid with standard alkali solution. Recommendations are made regarding the preferred methods of determining the constituents in dibasic aluminum nitrate and regarding means of minimizing errors in these analyses.

Several plates of 98.7% Th - 1.2% U 235 (clad in aluminum) were irradiated in the MTR for an integrated flux of 2.6 x 10 21 neutrons/cm2. Although these samples represent an early development in bonding of aluminum to thorium and there are better methods at present, the bond proved to be quite strong and both clad and core were dimensionally stable under irradiation. The production of uranium 233 was as much as theory would indicate and the total amount of fissionable material material after irradiation and after decay of the protactinium 233 was greater than before irradiation. A fuel element of this nature appears to offer excellent potentialities from the standpoint of radiation stability.

This report presents data obtained from processing 33 Clementine Reactor fuel elements in the ORNL Metal Recovery Plant to recover approximately 15 kg of plutonium and 0.16 g of americium.

Diffusion in an arc plasma across a magnetic field is investigated. The geometry is similar to that reported in ORNL-1890 but with the addition of magnetic mirrors on the ends of the arc chamber. It is shown that mirrors do not eliminate the "short circuit" effect. Comparison of the e-folding length, rₒ, of the radial ion density with and without mirrors, affords a direct measurement of ℓ/λ where ℓ is the arc length and λ the mean-free-path. In addition rₒ is independent of gas pressure with mirrors and varies as √p without mirrors. The condition for the elimination of the "short circuit" effect is discussed, as well as the case in which the "short circuit" is still present but the ions diffuse (rather than stream) to the end walls. In this case rₒ is directly proportional to the gas pressure. These effects are compared to some experimental results of Neidigh

Progress report of the Oak Ridge National Laboratory Aircraft Nuclear Propulsion Project providing updates on various projects, experiments, and other work. This report includes summaries of project activities in: aircraft reactor test design, ART physics, ART instruments and controls, component development and testing, procurement and construction, ART, ETU, and in-pile loop operations, phase equilibrium studies, chemical reactions in molten salts, physical properties of molten materials, production of fuels, compatibility of materials at high temperatures, chemistry, analytical chemistry, metallurgy, dynamic corrosion studies, general corrosion studies, fabrication research, welding and brazing investigations, mechanical properties studies, ceramic research, nondestructive testing studies, heat transfer and physical properties, radiation damage, fuel recovery and reprocessing, critical experiments.

This report presents a summary of certain physical properties that have been determined experimentally on the fluoride mixture that have been formulated at ORNL (Rers. 1, 2). These properties include the density, enthalpy, heat capacity, heat of fusion, thermal conductivity, viscosity, Prandtl number, electrical conductivity and surface tension. In addition to the experimental data, values have been predicted for the heat capacity and density of the other mixtures from the correlations of these properties. Estimates of the viscosity have also been made for a number of the mixtures on which no experimental data were available.

A satisfactory ion-exchange-polarographic method was developed for the determination of either chromium(VI) or total chromium in Homogeneous Reactor fuels. Total chromium is determined as chromium (VI) , i.e., chromate, and in the same way as is chromium(VI), after chromium in the lower valence states is oxidized to chromate by potassium permanganate. Chromate is separated from all interfering metal ions in the fuel by ion exchange on a Dowex 50 resin column. The Chromate in the effluent is determined polarographically in approximately 0.75 M sodium hydroxide solution as supporting electrolyte. A well polarographic wave is obtained for the chromium (VI) chromium (III) reduction at a half-wave potential of -0.85 volt vs. the S.C.E. The relative standard deviation of the data for 2 μg of chromium (VI) per ml was 2%; for 4 μg of total chromium per ml, it was 3%. An ion-exchange-polarographic method was developed also for the determination of chromium(III). Chromium (III) is separated from all interfering ions in the fuel by ion exchange on a Dowex 1 resin column. The chromium (III) in the effluent is determined polarographically in a 1M ammonia-1M ammonium chloride supporting electrolyte. The wave obtained at a half-wave potential of -1.42 volt vs. the …

The ORNL Graphite Reactor operated very well during 1955. The downtime was low, only 8.6%. The fuel in the bonded slugs did not perform as well in 1955 as in 1954. Much of the trouble was undoubtedly due to growth of slugs which were not beta-transformed. It is known that some slugs had grown over 1/2 in. The automatic central system installed in 1954 continued to operate satisfactorily. The cooling system gave minor trouble when one of the 900-hp fan meters had to be replaced because of shorts in the rotor. The high radiation in the canal was the largest source of trouble. Approximately 55 tons of slugs discharged from the reactor in 1952 was sent to the Metal Recovery Plant. Enough slugs had raptured, due to their long exposure in the canal and reactor, to badly contaminate of water. Most of the contamination was removed by the end of the year, but the radioactivity which had soaked into the canal wells was enough to give high radiation fields. A solution to this problem was being sought at the end of the year. A study is under way on the possibility of increasing the flux of the ORNL Graphite Reactor …

Progress report of the Oak Ridge National Laboratory Aircraft Nuclear Propulsion Project providing updates on various projects, experiments, and other work. This report includes summaries of project activities in: aircraft reactor test design, ART physics, ART instruments and controls, component development and testing, procurement and construction, ART, ETU, and in-pile loop operations, phase equilibrium studies, chemical reactions in molten salts, physical properties of molten materials, production of fuels, compatibility of materials at high temperatures, chemistry, analytical chemistry, metallurgy, dynamic corrosion studies, general corrosion studies, fabrication research, welding and brazing investigations, mechanical properties studies, ceramic research, nondestructive testing studies, heat transfer and physical properties, radiation damage, fuel recovery and reprocessing, critical experiments.