Abstract: Force, moment, and center of pressure information are presented for four models of the Hi-Lo configuration.

This course on reactor controls is for the purpose of acquainting the student with some of the elementary considerations involved in setting up a control and safety system for a nuclear reactor. This material is the outgrowth of the notes prepared for the lectures on Reactor Controls given in the Oak Ridge School of Reactor Technologu. The lectures given by T. E. Cole in 1953-1955 are the basis of portions of the subject matter on reactor kinetics. Many suggestions and ideas contributed by E. R. Mann are included throughout almost every section. In addition, several members of the Oak Ridge National Laboratory, and of the Reactor Controls Department in particular, have provided information which has been included in these lectures notes.

The results of a parametric study on a gas cooled reactor are reported on herein. The system considered was a helium cooled, UO2 fueled arrangement with the fuel assemblies consisting of clusters of long cylindrical elements, each element covered b a stainless steel jacket. The axial power distribution was assumed to be a "chopped cosine" having an axial peak-to-average power 1.32.

Relatively frequent agitator failures in HAPO Separations Plants have interfered with process continuity, contributed to process difficulties, and resulted in considerable maintenance expense. Predominantly the failures have been because of gear-reduction drive unit break-down or because of metallic fatigue and degeneration of the shaft-paddle assemblies. A simplified, slow-speed, direct drive agitator, previously described in HW-52755, proved to be quite durable and satisfactory during extended testing, operating without incident for over 10,000 hours. Subsequent operation of the agitator in the Redox Plant has been equally smooth. Total operating time (combined test and production use) is now in excess of 21,000 hours. Since the slow speed agitation principle has been adequately demonstrated at Redox and Purex canyon applications. This report describes the development and testing of such a "universal" agitator.

The referenced memo asked several questions on the operation of the Purex Plant which are of interest to the Eurochemic personnel. These questions are answered below. 1. A qualitative description of the nitric acid recovery systems is desired -- flow of materials, number of pieces of equipment, etc.

From Abstract: "This report is one of a sequence of quarterly reports, each designed to up-date its predecessor beginning with HASL-42, "Environmental Contamination from Weapon Tests." Herein are reported data which have accrued since HASL-51. In particular, the levels of strontium 90 in fallout, milk, tap water, vegetation, and foods are given, based on data available from November 1, 1958 to January 30, 1959."

Report documenting ongoing research and development carried out by the Instrumentation and Controls Division of the Oak Ridge National Laboratory.

Report documenting the ongoing research and developments of the Oak Ridge National Laboratory's Homogeneous Reactor Project.

The processing of spent fuels from nuclear power and propulsion reactors is planned by Hanford Atomic Products Operation as part of the Atomic Energy Commission's interim processing scheme. The spent nuclear fuels have cores of UO2, U, or alloys of U-Mb, U-Al, or U-Zr clad in either stainless steel, aluminum, or Zircaloy. This report discusses only the Zircaloy-clad fuels and the applications of the Zirflex Process for dissolution. Zirflex chemical flow sheets are presented as developed by pilot plant operations.

Examination of Al- 1.65w/o Pu and Al- 12 w/o Si- 1.65 w/o Pu capsules irradiated 55- 60% burnout of the plutonium atoms revealed a 1.4% volume increase and no apparent microstructural changes. A four rod cluster containing Al-8 w/o Pu and Al-12 w/o Si-8 w/o Pu alloy cores is currently under irradiation in Loop 3 of KE Reactor at a water temperature of approximately 230C. A second cluster has been fabricated an is scheduled for charging late in 1958. Two seven-rod clusters for irradiation in KER are also being fabricated.

This report is a summary of work done for system development on the NPR ball safety backup for the horizontal rods. This phase of the system development is limited to discussion of the horizontal rod counting circuitry utilizing a direct current bridge network.

This document presents preliminary chemical flowsheets for cladding and core dissolution of zircaloy-clad uranium dioxide and stainless steel-clad uranium-molybdenum non-production fuels. These preliminary flowsheets together with existing process flowsheets should be adequate for process development in the currently forecast non-production fuels dissolution facility.

Since the start of E-metal processing in December, 1958, critical mass control in the Redox dissolvers has been provided by a combination of administrative controls, revised dissolver charging procedures, and new dissolving processes and operation control procedures. These were all based on a maximum allowable charge of E-Metal to the dissolvers which was equivalent to 45 percent of the minimum critical mass.

In the field of nondestructive testing the ultrasonic test method is used extensively. In this method ultrasonic energy generated by a transducer is caused to enter the test specimen. The effect on the transducer is cause to enter the test specimen. The effect on the transmission or reflection of the ultrasonic energy by differing test specimen structure is used as an indirect measure of test specimen characteristics.