An instrument was developed to measure nondestructively the lithium content of target slugs for the SRP reactors. The slugs consist of cylindrical pieces of Li-Al alloy, approximately 0.8 inches in diameter and 12 inches in length, clad with aluminum. The instrument utilizes neutron transmission to determine the Li content in the range 3% to 7% Li.

This is the thirty-sixth progress report of the Laboratory for Nuclear Science at the Massachusetts Institute of Technology. Progress during the period of November 30, 1954 through February 28, 1955 is reported.

This report summarizes work completed during the Redox Plant shutdown in January 1955. An analysis of major difficulties encountered, improvements made during the shutdown, and building design deficiencies brought to light by the shutdown are discussed. (JL)

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In the light of Redox Plant performance since the start-up on 2-3-55, coupled with a review of the technological factors involved in the current flowsheet, a departure from the process program outlined in HW-34882 is herewith presented as an addendum to that document which will also serve to detail the corresponding items in the latest Redox Test Program, HW-35069. The purposes of this document are to: (1) Discuss the need for modifications of the program given in HW-34882, and (2) Present the details of the proposed revisions.

The new KW reactor was placed in operation on January 4, 1955, and had been running at relatively low power levels for only 17 hours when it was shut down because of a process tube water leak which appeared to be associated with a slug rupture. After several days of unrewarding effort to remove the slugs and tube by customary methods, it developed that considerable melting of the tube and slugs had taken place. It was then evident that removal of the stuck mass and repairs to the damaged tube channel would require unusual measures that were certain to extend the reactor outage for several weeks. This report documents the work and findings of the Committee which investigated the KW reactor incident. Its content represents unanimous agreement among the three Committee members.

This report covers the examination of nine process tubes, five tubes from B Pile and four from H Pile. Four of the tubes from B File were removed because they were leaking and the fifth was removed because it contained a stuck ruptured slug. Tube 2681-H was removed for graphite mining, tube 2852-H was removed under PT 313-105-14M ``In-Pile Evaluation of 63-S Aluminum Process Tubes,`` and two tubes were removed from channel 0961-H under PT 105-506-E, ``Recirculation of Pile Cooling Water.`` Visual inspection was made of the inside and outside surfaces of the tubes before and after cleaning with cold 10 per cent nitric acid. Samples varying from one to four inches in length were taken from each section and transferred to the 108-B Metallurgical Laboratory for close examination to determine depth of pitting, 72-S cladding thickness, and wall thickness. These determinations were made at specific points in each section on what appeared to be the area of severest attack. It is indicated on six of the tubes where the sample was taken on the circumference of the tube.

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Purpose of this report is to determine optimum tank size from evaluating the quantities of principal construction materials with prevailing unit costs for various tank sizes. The materials were concrete in-place, reinforcing steel in-place, wood framework, 3/8 in. C steel plate liner in-place, earthwork excavation and backfill (engineering, overhead, piping, condenser, vapor manifold costs not included). Costs of optimum tank are distributed as follows: dome 25%, walls 28%, foundation 6%, floor 2%, steel liner 20%, earthwork 19%. For a given tank capacity, there is a definite optimum tank size; as the capacity increases, the diameter increases, and the height increases but at a lesser rate. Each diameter has an optimum height, which is that height at which unit cost of storage space is minimum for a given tank diameter. Optimum unit cost is $0.136/gallons for diameters 75--130 ft; for diameters<75 ft, the optimum unit increases. Tank forms 241-S, 241-SX, and 241-A were used in this study; storage cost of the analyzed tank was $0.121 compared to $0.136/gallon for 241-SX and 241-A, and $0.152/gallon for 241-S. Assumed unit costs for concrete and steel plate tank liner were 10% less than those of 241-SX and 241-A, causing the lower unit costs. Tanks …

This document presents a summary of work and progress at the Hanford Engineer Works for January 1955. 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.

The magnetic susceptibility of artificial graphite was determined as a function of exposure in the MTR. Specimens were studied with exposures ranging from 0.07 to 82 {times} 10{sup18} nvt. Fluxes were determined by means of x-ray measurements and resistivity measurements. The dependence of the magnetic susceptibility on exposure in the MTR and also in a Hanford reactor are graphed, and an equivalence factor is calculated.

The overall process of photosynthesis involves a number of interconnected processes. These processes, which are cyclic with respect to both energy and material, are related at some points to well-known respiratory processes. The carbon-reduction cycle in photosynthesis is now known in detail. All enzymes involved in this cycle have been isolated and the sources of energy required for its operation have been identified in terms of reducing agents and 'high-energy' phosphate. These sources of energy a r e derived ultimately from absorbed light energy which brings about the photolysis of water. Possible mechanisms for this photolysis and for the transfer of energy from the photolysis products to the carbon-reduction cycle are discussed here. Experimental data, in the form of quantum efficiency measurements, are presented and partially confirm the theories proposed for the mechanisms of energy transfer. A diagram of the complete process of photosynthesis containing the several cycles and their relations is presented.

Heat transfer coefficients were determined for the eutectic mixture LiF- KF-NaF (Flinak) flowing in forced convection through circular tubes. Heat, electrically generated in the tube wall was transferred uniformly to the fluid during passage through small-diameter tubes of nickel, Inconel, and 316 stainless steel. The variables involved: Reynolds modulus (N/sub R//sub e/), 2300 to 9500; Prandtl modulus (N/sub P//sub r/, 1.6 to 4.0; average fluid temperatures, 980 to 1370 deg F; and heat flux, 9,000 to 192,000 Btu/hr-ft/sup 2/. Forced-convection heat transfer with Flinak can be represented by the general correlation for heat transfer with ordinary fluids (0.5 &lt; N /sub P//sub r/&lt; 100). The existence of an interfacial resistance in Flinak-Inconel systems was established and its composition determined. Preliminary measurements of thermal conductivity and thickness of film were made. The results verify the effect of the film on Flinak heat transfer in small-diameter Inconel tubes. Thermal entry lengths, determined from variations of local heat transfer coefficients in the entrance of the heated section, were correlated with the Peclet modulus. (auth)

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The design and economics of the Aqueous Homogeneous Reactor as basically under development at the Oak Ridge National Laboratory are presented. The reactor system utilizes thorium-U-233 fuel. Conditions accompanying reactor systems generating up to l080 mw of net electrical energy are covered. The study indicates that a generating station, with a net thermal efficiency of 28.l%, might be constructed for approximately 0/kw and 0/kw at the l80 mw and l080 mw electrical levels, respectively. These values result in capital expenses of approximately 4.72 and 2.86 milis/kwh. A major part of fuel cost is the expense of chemical processing. It is therefore advantageous 10 schedule fuel through a relatively large processing system since fixed charges are insensitive to chemical plant size. By handling fuel through a plant large enough for processing 200 kg of thorium per day, total fuel costa of about 1 mill/kwh result. This cost for fuel processing appears applicable to generating stations up to abeut 540 mw in size, decreasing to about 0.6 mills/kwh at the l080 mw level. Operating and maintenance expense, including heavy water cost on a lease basis, varies between l.34 and 0.89 mills/kwh for l80 and l080 megawatts respectively. If the purchase of heavy …