The status of development studies being conducted on a pebble bed power reactor is outlined. The items discussed are fuel element manufacture, stability, and reprocessing, and component development. (D.L.C.)

A comprehensive survey of the literature was made in an effort to identify nonmetallic materials of possible usefulness as liquid coolants. Materials having maximum melting points of 1000 deg F and boiling points of l200 deg F were considered, but boiling points above 2200 deg F were preferred. Melting points, boiling points, densities, heat capacities, and thermal conductivities were tabulated. Approximately 190 materials appeared to have melting and boiling temperatures in a suitable range. A paucity of thermal- conductivty and heat-capacity data prevented further estimates of suitability of all but nine of these materials. Of these nine nonmetallics, only sodium hydroxide appeared to offer possibilities when considered according to the NEPA formula. (M.C.G.)

The positional tolerance method of dimensioning is described. The emphasis is placed on the elimination of ambiguities and increase in tolerances provided by this method as compared to the older, bilateral method. (auth)

Two new positron active isotopes, B{sup 8} and Na{sup 20}, have been found to decay to excited states of Be{sup 8} and Ne{sup 20}, which in turn decay 'instantaneously' by alpha emission. Their half-lives are 0.65 {+-} 0.1 sec. and 1/4 sec. respectively. N{sup 12} is also found to have a low energy positron group which leads to an {alpha}-unstable excited state in C{sup 12}. The masses of B{sup 8} and Na{sup 20} are 8.027 and 20.015 respectively. B{sup 8} decays by a 13.7 {+-} 0.3 Mev positron, through the same excited state of Be{sup 8} as does Li{sup 8}. Estimates of the energies of the excited state in C{sup 12} and Ne{sup 20} are made.

The lifetime for the decay of a {pi} meson into {mu} meson and neutral particle was first measured by Richardson and later by Martinelli and Panofsky. The method was the same in both cases: The fraction of {pi} mesons surviving various times of flight is measured by placing photographic detectors at various path lengths from the target. In the experiment reported here we observe the time lag between the two bursts of fluorescence due to mesons decaying in a scintillation crystal. The first burst is due to the stopping of the entering {pi} meson, the second to the {mu}-meson. As is shown in Fig. 1, a particle penetrating the first and into the second crystal starts the sweep (10{sup -8} sec/mm) of an oscilloscope. The pulses in the second crystal are delayed 0.5 x 10{sup -6} sec to allow the sweep to start and brighten and are then photographed. If the responsible particle is a {pi}{sup +} meson which stops in the crystal, it undergoes {pi}-{mu} decay and two pulses appear on the trace. The {mu}{sup +} meson has a range of only 2 mm in the crystal. If its decay electron is detected some time (.5-2.5 x 10{sup -6} …

The fission reaction has been observed with high energy accelerator projectiles for elements as light as tantalum but has not been reported for medium weight elements. The present note presents evidence for the occurrence of reactions which are probably most properly described by the term 'fission' and which seem to occur with very small yield throughout the region where this type of reaction is only slightly exoergic or even endoergic with respect to mass balance. In the course of detailed investigation of the spallation of copper and the variation of the product yields with energy of the bombarding particle the threshold for formation of radioactive Cl{sup 38} (38-minute half-life) from elemental studied. The energetically most economical way in which Cl{sup 38} might be spallation reactions is by emission from the bombarded copper nucleus of nucleons in groups such as alpha-particles instead of single nucleons 0 The energetic requirements for the reaction Cu{sup 63}(p,pn6a)Cl{sup 38}, in which the maximum number of alpha-particles are emitted, include (1) the mass difference between the reactants and the products and (2) the excitation energy which the alpha-particles must have in order to pass over the coulombic barrier, Since the reaction is endoergic with respect to …

The conceptual design of a nuclear ram jet-rocket missile is preserved. This missile is a modified, scaled-up AC-210 nuclear ram jet carrying ammonia in the space enclosed by the spike and inlet diffuser. The payload may be a 10,000 pound thermonuclear weapon or equivalent weight of reconnaissance equipment plus local shielding as in the AC-210 missile. The payload for a missile of body size equivalent to the AC-210 will be reduced by the weight of ammonia.

The Uranium Recovery Process (TBP Process) at Hanford extracts and decontaminates uranium from the Metal Waste produced in the Bismuth Phosphate Process. Aqueous waste, approximately equal in volume to that of the Metal Waste itself, results from the process. Although of several years' age, these wastes are still sufficiently radioactive that they must be returned to underground tanks for storage. For several years aqueous wastes of low radioactive content have been discharged to ground at Hanford. Polyvalent cations are strongly absorbed by the soil. Monovalent cations are poorly absorbed if present in solutions of high salt content. Ground waters migrate toward the Columbia River very slowly. These observations point out the desirability of removing, from wastes to be cribbed, those long-lived radioactive constituents which are poorly absorbed by soil. Cesium (Cs-137) and strontium (Sr-90) are the principal constituents of Hanford wastes which possess these characteristics. Strontium, while more hazardous biologically, is of somewhat less concern than cesium because it is better absorbed from high-salt solutions by soils. This report describes research done to develop on inexpensive process for the removal of fission products, especially cesium, from Uranium Recovery Process Wastes. 4 refs., 13 tabs.

In view of current work on the Columbia River by the Biology Division and Development Division of the Health Instrument Divisions and the contemplated studies of the US Public Health Service Group new at Hanford, it was suggested that the groups review their programs related to studies of the Columbia River. The work carried out by the Control Functions Section of the Health Instrument Division in this respect is reviewed in outline form. Some of the studies are jointly carried out by the Control Functions Section and the Methods Group of the Environmental Hazards Section. The principal purpose for monitoring the Columbia River is to evaluate any radiation hazards that might exist as the result of discharging radioactive effluent into the river from the Hanford pile areas. The miscellaneous special studies conducted so supplement the routine monitoring program are pointed at into the river to better understand the effects of this radioactive contamination on the environment of the river and/or any drinking water supplies using the Columbia river as a source of supply. 1 fig.

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In accordance with the policy that a centralized inventory shall be kept of all radioactive waste liquid discharged to ground, it is recommended that the volumes of condensate from the SX-farm, the dates or periods of discharge, and the activity densities of radioisotopes in the condensate discharged be determined by Separations Section and reported regularly to the Radiological Standards Unit. This paper is a description of the condensate system, with recommendations for sampling and analysis.

A common and useful assumption is that the front-to-rear power distribution is a shortened cosine curve. This fact led to the calculation of slug factors'' for the longer charges to be used at K-Pile. It is hoped that the publication of these numbers will save time and prevent duplication of effort by those concerned in any way with slug power, surface temperatures, reactivity effects, etc. For the sake of completeness, slug factors for the older piles are included. Another useful ideal is that tube power distributions can be approximated by the assumption of a cylindrical pile and a cosine distribution of power outside of a central flattened region. This led to another double set of numbers since the values for the 2004 tube piles were again included for completeness. 2 figs., 6 tabs.

An engineering flowsheet has been prepared for the conversion of an aqueous slurry of cesium-zinc-ferrocyanide into a dry cesium chloride product by the calcination process. Flowsheet No. 1 defines a six-step batch-type calcination operation for processing the slurry into a dry powder for offsite shipment in bulk containers. Some of the advantages to this process are as follows: Product losses are expected to be small, estimated to be less than 0.03 percent; the equipment required to process a given number of curies per batch appears to be relatively small, compact, and simple; the process does not impose severe requirements for materials of construction; and requirements for process control and instrumentation are expected to be simple. There are two disadvantages to this process. First, the cesium-zinc-ferrocyanide precipitate is not considered economically filterable, hence, the separation of solids from liquids is encumbered. Second, the process, as outlined, if potentially hazardous because of the possible nitrate carry-over with the influent slurry. This nitrate may cause a rapid reaction in the calcination step. It is concluded that this flowsheet offers a satisfactory scheme for isolating radiocesium if the process is modified to preclude the possibility of nitrates or other unwanted oxidants from reaching the …

The General Electric Company has prepared in past years numerous documents for the Atomic Energy Commission outlining in some detail its current and proposed programs at Hanford. Last year, at the request of the commission, program types of information were consolidated into one document, the HAPO Five Year Program. That document was well received and useful to an extent that the General Electric Company was requested by the Commission to prepare another covering the fiscal years 1959 through 1963. In outlining the five year program for the Hanford Atomic Products Operation, the General Electric Company has made assumptions regarding the US Atomic Energy Commission`s current and future programs and Hanford`s relationship to these programs. Two major objectives of the Commission were considered basic for future planning: first, to provide adequate atomic weapons for national defense; and second, to encourage and assist in the development of atomic energy for peaceful uses. The Hanford contributions to these objectives are conceived to include the acquisition and potential application of new technology in support of: (1) Increased production of plutonium, as nitrate solution, buttons, and as current and future shapes. (2) A program that will provide the technological capability to implement broad changes in …

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The purpose of this report is to present a basis for the application of slug corrosion rate data to corrosion limitations on pile power levels.

The objective of the production test described in this report is to provide the authority and mechanism to remove process tubes from the piles for inspection. The test is intended to provide a more positive tube inspection program than was previously provided under production test number 105-9-P, ``Corrosion of Slugs and Tubes``, document number 7-3928.

A knowledge of the mechanical and physical properties of uranium is important in understanding its pile behavior. The effects of irradiation on the properties of uranium will be dealt with in another chapter. However, it is important to know and understand the pre-irradiation properties of uranium prior to investigating the effects of irradiation. This chapter discusses the mechanical and physical properties of uranium.

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This document provides the required definitive scope design for dissolver equipment capable of nuclear safe processing by geometry of E-Metal and certain other fuels enriched to a maximum of one per cent U-235 equivalent. Using only a single dissolver installation of this design, it will be possible to process the current E-Metal monthly commitment in less than two weeks (five-day week). The proposed dissolver system is to incorporate design flexibility required to permit conversion to Zirflex processing of NPR fuels.

This is a progress report of the production reactors on the Hanford Reservation for the month of April 1951. This report takes each division (e.g., manufacturing, medical, accounting, occupational safety, security, reactor operations, etc.) of the site and summarizes its accomplishments and employee relations for that month.

Since the installation of Ball 3X equipment on the older reactors, several inadvertent ball drops have been experienced, many of which have required considerable recovery time. Furthermore, it is very probable that these recovery times be significantly increased subsequent to the proposed installation of air accelerated vertical safety rods. Because of this, interest has been expressed by reactor operations personnel toward provision of a ball recovery system which would substantially reduce these outages.

During the history of operation of the Hanford reactors, several methods have been utilized to establish an outlet water temperature or ``Panellit`` limit based on the stability of water flowing through the process tubes. These methods have been known as ``Excess Header Pressure Limits,`` ``Trip Before Boiling Limits,`` and the most recent, ``Trip Before Instability Limits.`` Each new concept vas accepted only after considerable experimental data had proved the new method to be safe and operationally feasible. It is anticipated that in the future other tube outlet water temperature limits will be developed based on new technology. The purpose of this document is to present, in simple terms, an understandable explanation of previous operating limits, to discuss the status of the present Instability Limits, and to outline the direction of future work in raising the outlet water temperature limits.

This document presents a summary of work and progress at the Hanford Engineer Works for April 1956. 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 summaries 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 Service departments have sections presenting their monthly statistics, work, progress, and summaries.