Optical microscopic examination of air- and rain-borne dust shows most of the particles to be less than one micron in diameter. Electron microscopic examination of the same dust shows predominantly clusters of particles whose individual diameters are in the range 200 to 1000 A. The residue obtained by filtering rain water through a millipore filter is found to be slightly radioactive in more than half the cases observed.

During an experiment involving alpha phase annealing (at 610 to 655 deg C for 5 and 10 min) of beta-quenched uranium, it was determined that the relatively coarse, irregular shaped grains (0.08 to 0.150 mm in diameter) in the beta-quenched structure, were replaced by fine equiaxed grains (0.04 to 0.09 mm in diameter). (auth)

In the most general sense, an accelerator is any device designed to give kinetic energy to ions or electrons. According to this definition the earliest cathode ray and canal ray tubes, made before the turn of the century were accelerators, the same principle is used in the x-ray tube, the cathode ray oscilloscope, the mass spectrograph, the electron microscope, and many other modern devices. However, we shall limit this discussion to those accelerators made for the particular purpose of inducing nuclear reactions, and to a few others that may be of interest in this connection, although they were originally designed for other purposes, such as high-voltage x-ray tubes intended for deep therapy or the radiography of metals. Although much work related to accelerators is thus omitted, it must not be forgotten that the principles learned and the practical experience gained by this work were of great importance in the development of the machiens now used in nuclear physics.

In view of contamination difficulties within the Redox operation, number of items are being considered to improve this situation. It is the objective of this document to list and describe seven times which it is felt would contribute most toward improvement. It is also an objective to present for RDS-D-12 Group consideration the recommendations of representatives from Manufacturing, Technical, and Design in these matters with the expectation that a project proposal written in general terms for overall contamination improvement would be prepared.

This report discusses two methods which have been considered to reduce the rear face activity. The first involves the use of a solids purge to scour out the activity, and the second employs the use of a chromic acid purge to put the activity into solution. Solids purging is found to be ineffective in reducing rear face activity levels. A chromic acid purge conducted at 60 C for 1/2 hour can be expected to reduce the Zn{sup 65} activity level about five fold without injuring the reactor or causing any harmful aftereffects.

It is the purpose of this document to review and up-date the previously presented scope basis for the activated silica installations in light of the existence of the Phase I portion and the present expected water flow requirements of Project CG-558. It is the further purpose to outline the recommended scope bases for the sulfuric acid addition system for pH correction at all areas.

The program of the Pile Graphite Studies Unit for the past two years has been directed toward relaxed graphite specifications. The main emphasis in these studies has been on the feasibility of higher permissible maximum graphite temperatures and higher percentages of helium in the gas systems. The success of this program is evidenced by the potential pile power levels permitted by present process specifications. The present graphite Process Specifications will not permit heat generation associated with tube powers above 800 KW at, B{sub 9} D{sub 9} and F Piles. Therefore, further relaxation is necessary if tube powers of 1000--1200 KW anticipated after completion of the water plant expansion program are to be realized. In extending the present program to permit these anticipated tube powers, production tests authorizing full pile tests for raising permissible maximum graphite temperatures and increasing the percentage of helium are necessary. A production test authorizing the operation of D Pile at sufficient constant power level to attain graphite temperatures of 460--500 C with 60{plus_minus}5 percent helium has been agreed upon and is now circulating for final approval. A production test has been prepared to evaluate graphite burnout, rates at maximum temperature of 600 C with localized regions …

This document presents a summary of work and progress at the Hanford Engineer Works for December 1954. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Real Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.

Undesirably high radiation dosage rates are being encountered in the discharge areas during reactor outages. This is costly to operations in terms of burn-out time, extra work crews, and extended outages require to complete scheduled work. Significant savings in operating costs would be realized if the rear face radiation levels could be reduced during shutdowns. As a first step towards this some measurements have been made to identify and locate the major sources of this radiation. These results are given in this report. It is suggested that this information may be of use in devising a water treatment or purge technique which could reduce the rear face contamination problem encountered during outages.

The object of the production test described in this report is to obtain full pile high temperature graphite burn-out data. In addition, the test will supply valuable data on the postulated influence of neutron temperature on plutonium purity.

None

None

During the summer months of 1954, the spare 190-C process pump unit was required to be placed in service for extended periods of time due to the motor winding temperatures exceeding the manufacturers recommended maximum operating limits. With nine unit operation each pump was required to supply approximately 9800 gpm to maintain the established power level of the 105-C Reactor. An operating condition requiring all process pump units to be in service simultaneously is-not desirable. Such a condition not only subjects the Reactor Unit to a possible unscheduled outage should trouble develop in any component of a pump assembly but in all probability would delay a startup of the Reactor Unit until arrangements could be completed to operate at reduced pressure in order to eliminate sustained over-heating of the pump drive motors. The purpose of this report is to summarize the activities undertaken during this investigation in order to arrive at satisfactory conclusions and recommendations for eliminate the over-heating of the related motor windings under present and proposed operating conditions.

The theory of isotope separation by countercurrent chemical exchange is worked out in detail using the continuous transfer concept. A comparison is made with discrete stagewise processes such as gaseous diffusion and with various general concepts of solvent extraction. The effects of a cell structure in the flow system is also worked out. An elementary design procedure is included both for the no-loss case and the case where the losses are small. In addition, a method of estimating stage lengths or transfer rate constants from small scale batch experiments is presented.

None

None

None

None

An analysis of the self-limitation of power excursions by steam production in heterogeneous water-moderated reactors using MTR- type fuel elements seems to give excellent agreement with Borax data on both fuel plate temperature rise and total energy for excursions in which the reactor is initially at saturation temperature. A simple model for steam production is developed from thermodynamic and heat diffusion considerations. In those cases for which the reactor is substantially sub-cooled, it appears that for MTR fuel elements, at least, all the water in the coolant channels at the hottest part of the reactor must be heated to saturation temperature before steam is produced. The theory is used to discuss the safety merits of research reactors which differ in neutron generation time, steam void coefficients and hydrodynamic characteristics. It is shown that D/sub 2/O reactors of the CP-5 type, because of their long neutron lifetime, can safely selflimit power excursions resulting from much larger reactivities than can the H/sub 2/O reactors of the swimming pool type. On the other hand, the response of the two reactor types to equivalent accidents, such as the addition of a given amount of fissionsble material, is practically the same. (auth)

None

Some of the principal problems faced in the mechanical and thermal design of the Shippingport Pressorized Water Reactor core are discussed. The interplay of these problems with the requirements of other technologies is discussed, and areas which need more work are outlined. (M.H.R.)

None

None

None