This paper describes the measurement of control rod strength in the PCTR. The first section outlines the theory and method of such a measurement, and the second section presents the results of the measurement of the Experimental Gas Cooled Reactor (EGCR) control rod strength. The reactor parameter actually inferred is the difference in the infinitive multiplication factor for a control rod supercell with and without the control rod in place in the supercell. These measurements are, therefore, very closely related to the measurement of k∞ for an ordinary lattice cell.

High speed data handling and computing systems are coming into increasing use in the automatic control of complex industrial processes. One of the next significant developments in reactor design is believed to be the application of high speed data handling and control systems to nuclear reactors. This document is a study of such a system intended for use with the Plutonium Recycle Test Reactor.

This article presents data on the effects of gamma radiation on the physical properties of a number of different classes of plastics materials of construction which were screened to determine their capabilities and limitations for service in applications where ionizing radiation exists. The irradiations were carried out in air at ambient temperature at normal atmospheric pressure to various gamma radiation doses up to 1*10^9 r depending upon the stability of the materials to radiation exposure. The different classes of materials and materials within a class are compared.

The design of NPR shows large quantities of carbon steel pipe and fittings in the front and rear face areas. These are also the area where the most work must be done during an outage, and consequently lower radiation levels are needed here than elsewhere in the piping system. A single pass decontamination of the front and rear piping without going through the entire loop is desirable. Because of the quantities of chemicals and available down time, an effective shorty interval process is needed. This report gives some recent laboratory data on this subject.

The subject of this report is the generalized computer program written to solve problems involving steady fluid flow through heterogeneous, partially-saturated porous media.

In the past several years the use of neutron monitors for Pu concentration monitoring has been expanded in the Chemical Processing Department. Most of these monitors have been quite successful, and considerable effort is being made to improve the operation of both existing and future monitoring systems. One of the major improvements has been the development and use of a transistorized pre-amplifier or impedance matching circuits. This unit solves several problems associated with the use of boron trifluoride (BF3) neutron detectors in process monitoring; e.g., vacuum tube pre-amp failure because heat is not being conducted away.

The evaluation of the inductance of an electrical component is often important in understanding and operating an electrical circuit. Inductance is defined by several equations, the most common being e= -L d1/dt . This equation defines inductance as the constant which relates the back emf produced in an element to the time-rate-of-change of current.