Report documenting ongoing experiments, designs, and tests undertaken by the Oak Ridge National Laboratory for the Molten-Salt Reactor Project.

Report containing reports from the Physics Division of the Oak Ridge National Laboratory that cover a wide variety of subjects.

Report containing ongoing research and development taking place at the Oak Ridge National Laboratory's Electronuclear Division.

Report containing ongoing research and experiments of the Oak Ridge National Laboratory's Instrumentation and Controls Division.

From foreword: "This is a documentation of the experiments performed and the data accumulated during the early period of the Experimental Gas-Cooled Reactor (EGCR) fuel element design."

Report documenting the problems, design, and operation of countercurrent liquid-foam columns.

Report issued by the Oak Ridge National Laboratory discussing revisions to previously issued conversion coefficient tables. The revised tables are presented. This report includes tables, and graphs.

Report issued by the Oak Ridge National Laboratory discussing the development of a closed-loop control system. As stated in the statement, "the purpose of this thesis was to design and build a closed-loop control system to be used as an indicator of the level of high temperature liquids contained in a tank" (p. 1). This report includes tables, illustrations, and photographs.

Report issued by the Oak Ridge National Laboratory discussing radiation corrosion studies. As stated in the introduction, "the purpose of this experiment was to compare the performance of a large number of materials under similar irradiation and exposure conditions" (p. 1). This report includes tables, illustrations, and photographs.

Report issued by the Oak Ridge National Laboratory discussing natural-circulation corrosion test loops. As stated in the abstract, "an investigation was undertaken to determine the compatibility of conventional nickel, iron, and cobalt-base high-temperature alloys with boiling potassium. The tests were designed to obtain quantitative information on the dissolution of the container alloys by condensing potassium and the subsequent deposition of solute in the subcooled liquid region of the test device" (p. 1). This report includes tables, illustrations, and illustrations.

Report containing experiments conducted at the Oak Ridge National Laboratory's Critical Experiments Facility. These experiments involved "determining the critical parameters of the assembly with varying amounts of neutron absorber in the D20 reflector, measuring the relative neutron flux distribution for various conditions of reflector poison and fissile solution concentration, determining the ratio of the absolute thermal-neutron flux in the center of the assembly to the power in the fissile solution , and determining the effect on reactivity of reducing the hydrogen density in the central region of the assembly" (p. 1).

In a sense, the whole process of differentiation is one of directed functional mosaicism. It is, however, the accidental or random juxtaposition in the same organism of cells having actually or effectively different genotypes that is generally thought of as true mosaicism. The study of this condition constitutes a perfect meeting place for the fields of genetics and developmental biology, providing, as it does, interrelated information on mutability, cell lineage (including the special problems of cell lineage of the germ line), and the effect of genotype on part of the organism versus the whole. The discovery in recent years that most or all of one X chromosome of the normal mammalian female become randomly inactivated early in development, an event that leads to functional mosaicism, provides us with a great potential tool for the study of gene action. The present paper will attempt to bring together results of diverse observations and experiments (many of them as yet unpublished) bearing on both genetic and functional mosaicism in the mouse.

A replica electron microscope study of as-polished and cathodically etched surfaces of pyrolytic carbon coating on fuel particles has been made in an attempt to characterize coatings that showed as much as a 30% difference in bult density. High and low density coating could be characterized by their polished surface textures; however, these features were not indicative of the true structure as seen by direct electron transmission. Microvoids detected by the transmission study of cleavage flakes exist on too fine a scale to be observed either optically or by electron microscope examination of replicas of the polished surface. Other features such as the effect of cathodic and chemical etching, coating delamination, and duplex coating interfaces have also been examined.

In some recent experiments the ion density in a plasma was measured as a function of radial distance from a d-c arc source of ions for the magnetic field intensities from 2500 to 14000 oersted. The diffusion coefficient appeared to very inversely as the square of the magnetic field strength, D~1/H2. The absolute value of D was shown to be approximately that which would be predicted by the collision diffusion theory when account is taken of the shorting effect of the end walls. The purpose of this report is to continue the examination of ion diffusion in a plasma and field experimentally the relation between the diffusion coefficient and the neutral gas pressure for a constant magnetic field.

This quarterly progress report of the Aircraft Nuclear Propulsion Project at ORNL records the technical progress of the research on circulating-fuel reactors and ether ANP research at the Laboratory under its Contract W-7405-eng-26. The report is divided into three major parts: I. Reactor Theory, Component Development, and Construction, II. Materials Research, and III. Shielding Research.

Continued work on the adsorbability of metal complexes from concentrated LiCl solutions and LiCl-HCl mixtures on a strong-base anion-exchange resin further demonstrated the much higher adsorbability of these complexes from LiCl solutions than from HCl solutions. The effect is believed to be due to the formation of less strongly adsorbed undissociated chloro-complex acids in the case of the HCl solutions.

The use of a scalloped cross-sectional coolant channel has been suggested as possible solution of the fuel-element bowing problem inherent in the septafoil type of geometry. Using simplified assumptions, a method has been developed for calculating the rod spacing and scallop size necessary to produce equal average fuel-element surface temperatures in the central and peripheral regions of the coolant flow channel at the mid-section of each fuel-rod cluster under a given set of reactor flow conditions. Since the extent of row-bowing is related to the surface temperature distribution, this requirement should minimize fuel-element deflection.

In conjunction with Gas-Cooled Reactor heat-transfer studies, local and mean heat-transfer factors are predicted from the heat transfer-mass transfer analogy using subliming naphthalene in air. Experimentation was conducted on 1-in.-dis septafoil rods in a 4-in. -dis flow channel with rod center-to center spacings of 1.10, 1.25, and 1.40 in. at a Reynolds modulus of approximately 60,000. Ratios of local mass transfer to mean mass transfer for a given rod vary as much as from 0.7 to 1.3 (outer rod, 1.10-in. spacings). Mean values of the mass-transfer factor are, in general, above that predicted by the correlation j-0.023 NRe^-0.2; as much as 46% got the outer rod t 1.25-in. spacing. The data indicate that for maximum mass transfer and minimum variation of the mass-transfer factor, an optimum rod spacing exists; the best observes is at 1.40-in.

This report supersedes ORNL CF-57-2-1, which was an extension and revision of ORNL CF-54-6-72. Details concerning a recommended system of flow-plan symbols and drawing are given. The system is designed to identify the function of all major instrument components and to show schematically the operation of the instrument relative to the particular process. The system is used for identification and designation. The system is a modification of the Instrument Society of American Recommended Practice (RP 5.1).

The new and as yet unsolved problems introduced by the production of large quantities of fission products and radioactive isotopes from fission or neutron capture present mankind a most complex technical, economic, and political problem. On one hand, the possibility of using the fission process to produce energy from an unexploited and abundant natural source is emerging from large programs of research and development. We are also beginning to see the promise of use of particulate and electromagnetic radiation for the good of man. On the other hand, we are presented with the problem of controlling the dangerous products of fission for periods of time measured in terms of many hundreds of years, periods longer than the effective tenure of any political state in history. We must not only devise ways of protecting ourselves in the present and for our lifetime but, in addition, we must establish the basic technical, social, and administrative control of vast quantities of artificial radioactivity that must remain effective for at least ten to twenty lifetimes.

The general Wigner-Eisenbud theory is used to develop a method of analysis for the cross sections of fissionable nuclei. The method is employed in giving a reasonable description of the low energy cross sections in U/sup 235/. The single level fit for U/sup 235/ is known to be unreasonable. Many level expressions for the cross sections are derived--the only approximation to the general theory being the neglect of all but a small group of resonances. It is shown that regardless of the number or definition of the fission channels the many-level expressions require few level parameters: the E/sub lambda /, GAMMA / sub lambda n/, GAMMA /sub lambda gamma / and GAMMA /sub lambda F/ of the single level theory for each resonance and a few additional parameters pertinent to the interference between levels. The interference terms are described and shown to be important. The shape and size of the U/sup 235/ cross sections below 2 ev are fitied to within one per cent using (a) only one negative energy resonance of smaller size than in the single level fits (b) no additional levels to fit the shape other than the observed levels at positive energies (c) three interference parameters …

The Eyewash program, written by James H. Alexander and Nancy D. Given, provides solutions of reactor criticality problems in spherical geometry by means of the group diffusion method. It employs thirty lethargy groups (plus one thermal group) in nine regions. The input consists principally of specifying the geometrical scaling factor, boundaries and compositions of the various regions, and temperature level. The output includes the value of vc that would render the system critical, the relative fission density distribution, fissions, absorptions, and leakages in each lethargy group in each region, and, if desired, an edit of the flux at each space point, each lethargy, and an edit of the macroscopic cross sections for each lethargy, each region. OCUSOL-A is a minor modification and extension of Eyewash. It provides for the computation and editing, on the supervisory control typewriter, of the total absorptions in selected nuclides in the various regions. This information is useful in the computation of breeding ratios and the preparation of detailed neutron balances, and in the estimation of flux-averaged cross sections for use in estimating the rate of change of concentration of the various nuclides with burn-up. The program also provides for saving and transferring the final fission …

Test work was completed on development of a stripping method for the amine extraction (Amex) process which produces a concentrated uranyl nitrate solution for shipment to the refinery. This procedure offers potential cost savings by simplifying the overall mill-refinery flowsheet. The process involves treatment of the amine extract with calcium nitrate solution to convert the uranium in the solvent to a nitrate complex, stripping the uranium with water or dilute nitric acid, and recovery of nitrate from the solvent for recycle by contact with a lime slurry.

The OCUSOL-A program (ORNL-CF-57-6-4) for Univac is a modification of the Eyewash (ORNL-1925) multi-group, multi-region reactor code. The group=energy-lethargy-temperature relationship are given in Table A. The element code numbers are given in Table B. The cross sections now on the sigma-tape are given in tables in the Appendix numbered with the element code number. This technical report explains the bases for choosing the cross sections.