Summary: The use of dimensionless-parameter frequency response diagrams to determine accuracies of lumped-parameter approximations is demonstrated by two examples: calculation of the heat flux at the surface of a semi-infinite solid due to temperature fluctuations of an adjacent fluid; and the response of a counterflow heat exchanger to inlet fluid temperature perturbations. Dimensionless system parameters make it possible to use general-purpose plots to find the error in particular approximations as a function of the frequency of perturbation. Such plots are directly applicable to control-system stability problems, where the highest frequency of interest is usually apparent.

This manual gives a description, operating instructions, circuit diagram and parts list of Transistorised Temperature Controller type 30 designed in the laboratories of the Australian Atomic Energy Commission.

Abstract: The use of a high energy proton or electron beam, directed vertically to act as a probe for the study of atmospheric processes is proposed. An outstanding feature of such an atmospheric probe is its capability to ionize a column of air repeatedly in a few microseconds and in approximately the same place. Characteristics of a vertical proton beam which may be generated by the Zero Gradient Synchrotron at the Argonne National Laboratory are discussed and calculations are presented to provide an estimate of the ion concentration as a function of height in the atmosphere. The potential uses of an atmospheric ionized column for meteorological research are discussed such investigations include the artificial initiation of lightning, the production of atmospheric ozone resulting from lightning, and the line spectra associated wit the lightning channel. Also presented is a method whereby a combination of the igh energy particle beam and infrared techniques may be used to determine the air circulation within a thunderstorm. Brief mention is made of the possible uses of a high energy particle beam for aerospace sciences, such as the study of whistlers and elecro-magnetic radiation phenomenon associated with the aurora and airglow.

Abstract: (1) Grain growth in UO2 pellets was studies between 100 C and 2600 C. The pellets were encapsulated in small vacuum-tight tungsten containers in an argon atmosphere. (2) The grain size-time relationship could be expressed by an equation. A low exponent, m>_ 1/3, was found in those experiments and is related to the type of UO2 investigated. An activation energy of 65 kcal/mole was obtained for the grain growth process. The time exponent, m, increased with increasing temperature if the pellets were not contained in closed capsules bu heated under an argon pressure of 1.5 atm. (3) An interaction between tungsten and UO2 could be observed at a a temperature of 2600 C after prolonged heat treatment.

Summary: The Mixed Spectrum Superheater (MSSR) is an integral superheater reactor in which boiling occurs in an annular Boiling Water Reactor section and steam in superheated in an unmoderated fast section in the center. A Mixed Spectrum Critical Assembly (MSCA) to be operated at the Vallecitos Atomic Laboratory has been designed to mock up a 75-150 MWe prototype MSSR. The principal experimental measurements aimed at proving the feasibility of the MSSR concept include power distribution, Doppler effect, flooding effects, distribution of reactivity, control rod worths, and the effect of the control system on the power distribution.

From introduction: "This is the sixteenth in a series of quarterly reports which cover the progress and results from the conceptual designs, economic evaluations and research and development work performed by the General Electric Company as part of Contract AT(01-3)-189, Project Agreement No. 13."

Introduction: The purpose of this technical report is to review the water chemistry methods and equipment developed for use with the Maritime Loop Irradiation Program conducted in the General Electric Test Reactor (GETR) from December 2, 1960 to July 19, 1962. Special emphasis is given to areas having general application to other high purity water systems. The Appendix includes a discussion of specific conductivity and pH in high purity water systems. A major section of this report is devoted to a review of gross activity levels on coupons of two different surface finishes exposed in the loop coolant system for various time intervals. A major objective of the chemistry program was to select or develop analytical methods such that the analyses could be performed at the loop location by technical personnel who normally operate the loop. By this means, frequent samples were obtained and analyzed directly thus providing close monitoring and control of the loop water chemistry at minimum expense.

Abstract. Some diffusion parameters of water are computed with various thermal-neutron scattering laws. It is found that the diffusion cooling coefficient, in particular, is reasonably sensitive to the scattering law, but that the diffusion cooling coefficients predicted by the Radkowsky and Nelkin kernels are in fortuitious agreement. The coefficients computed for the Nelkin kernel, when treated in a manner consistent with the way in which experimental data are treated, are in reasonable agreement with the results of a recent experiment.

Abstract. A brief review of the development of the subject of lattice defects in solids is given. The relation of this problem to field theory methodology is discussed; the defect is regarded as a particle imbedded in the phonon field. One may then discuss scattering states in the field, or “dressed” states of the particle. Specific application is then made to a defect in a simple cubic crystal including interactions between the defect site and its six nearest neighbors. Scattering solutions and scattering cross-sections are calculated and show that vacancies can cause strong resonant scattering, or pseudo-localized modes, at frequencies well below the Debye frequency. Applications to thermal conductivity and other experiments are discussed briefly.

FLOSS III is a third-generation version of a digital computer program which solves a one-dimensional difference representation of the momentum, energy, continuity, and state equations for turbulent, compressible gas flow in equivalent hydraulic channels. Extensive use of this program has been employed in the design and performance analyses of Pluto-type nuclear heat exchangers, and in the specific case of the Tory II-A test series, agreement was obtained to better than 5% for all experimentally measured parameters. The NOMAC and DASH-N programs combine the effects of up to thirty varieties of channels with the dependent boundary conditions imposed by a common inlet diffuser and exit nozzle. The resulting calculations yield performance information for blow-down facility and ramjet flight condition application of the heat exchanger.

A summary of the available literature on the development of the various processes for the separation of uranium and thorium from aqueous nitrate solutions is presented. Flowsheets are given corresponding to the various stages in the development of the Thorex processes.

Modifications to the A.A.E.C.'s Siemens Diffractometer are described which enable precision lattice parameter determinations on single crystals. Analysis of the errors and consideration of results suggest that accuracies of about 1--2 parts in 10/sup 5/ are obtained on small beryllium oxide crystals. Details of alignment and measurement procedure are included.

The results of unclassified experiments on the irradiation behaviour of BeO fueled with UO2 and (U,Th)O2 are summarized and discussed. The overall picture is still somewhat confused owing to the different experimental conditions used by different workers. A serious deficiency in most of the work is the failure to quote the energies of the irradiation neutrons and it is not clear whether the observed changes are due to fission fragment or fast neutron bombardment. The irradiation behaviour, in general, appears to be good up to fission doses of at least 5 x 10(20) fissions cm-3 of dispersion.