Abstract: This technical report consists of series of drawings of the instrument with the following explanation. The modification of the Simpson Methane flow proportional counter consists of a means for inserting and replacing samples into the chamber through an air-lock device which avoids the introduction of even a small quantity of air into the active volume of the chamber. This is accompanied by sweeping out the small volume of the air-lock containing the sample with methane gas before the sample is introduced into the chamber -- this sweeping out requiring only a few seconds. The mechanical construction is somewhat simplified over that employed in the Simpson counter design, although the electrical and counting characteristics are essentially duplicates of those employed in the Simpson version. Voltage plateaus about 400 volts long, flat within 1% per 100 volts are obtained with the counter, with the operating point at about 2500 volts for methane at one atmosphere pressure. A plateau extending over a range of about 40% variation in amplification factor is obtained. Standard samples have been checked to standard deviation of +/-0.3% over a period of one year. The counter is rather gas-tight and is ready for use within about ten minutes …

Introduction. The main objective of the Metallurgical Project was the preparation of large quantities of plutonium 239, an isotope of element 94, by the interaction of neutrons and uranium. At the beginning, only predictions of its chemical and biological properties could be made since it is a new element. It was predicted that it would be toxic to tissue by virtue of its high atomic weight, and in addition, that it would be toxic by virtue of its radioactivity. Thus, the preparation and use of the element on a large scale meant the manipulation of, and possible exposure to, toxic quantities. It was, therefore, of practical importance to obtain data which would elaborate on the predicted toxicity. The objectives of the work reported here were to establish the acute toxicity of plutonium in experimental animals and to study the distribution of the element in the body after the administration of a wide range of doses. In the interest of economy of what was, at that time, a rare substance, and of animals and facilities, these two objectives were frequently pursued in the same experiment. The information obtained from the separate experiments is therefore frequently incomplete in one or another respect. …

Redux is a thermosetting synthetic resin manufactured by the Resinous Products & Chemical Co., Washington Square, Philadelphia 5, Pa. According to the manufacturer, it is intended for bonding metal to metal and metal to wood. It was apparently intended to replace rivets in aircraft structural parts and recent information indicates that a British airplane, the DeHaviland Dove, is in production using this resin. The adhesive was originally developed in England by Aero research Ltd. Experience at this laboratory has been confined to use of the resin for bonding electrical grade silicon steel laminations. Very strong bonds have been obtained under properly controlled conditions. The bond strength is sufficient to tear 29 gauge (.014") steel when attempting to peel off individual laminations. The bond is sufficiently homogeneous to prevent leaks parallel to the plane of the laminations into a high vacuum system. Experiments at the laboratory have been designed to test the adhesive for use in bonding the laminations which form the pole tips and vacuum chamber lids for the synchrontron magnet.

The emf of galvanic cells at high temperatures was measured using uranium metal in equilibrium with its chloride as one half of the cell, the other half of the cell being some reference electrode such as silver - silver chloride. Several designs of cells tried are described. A value of 2.83 volts/eq. at 1170[degree]K and also at 990[degree]K is considered as the most probably value for the potential of the uranium halide couple.

Abstract: Exposure of Sprague Dawley white rats to single doses of 900 kvp X radiation demonstrated a medium lethal dose of 600 r which was not markedly dependent upon sex, weight, or, in the case of females, stage of the estrous cycle at the time of irradiation. Deaths within 30 days were most frequent between the fourth and eighth, and between the tenth and fifteenth post- irradiation days, indicating the existence of at least two processes leading to death in the "acute" period.

Report describing results of experiments that involved injecting radioactive yttrium into animals: "The excretion, retention, and distribution of the yttrium was measured, and its effect on survival and growth was observed. The average total excretion of Y91 to the time of death (from 76 hours to 24 days) was a little less than 30 per cent of the injected dose" (p. 2).

Abstract: In the Biology Division, the maintenance of animals containing radioactive materials posed many problems. In addition to routine care of the animals, protection had to be provided for the personnel who worked with the contaminated animals. Frequent air changed in the room in which the animals were caged were necessary: farm workers were required to wear masks; animal cages were checked regularly for radiation; acid was used on the sawdust in the excrete pens; and a new, more efficient type of cage was designed. The most import feature of the new cage was that the support for the screen floor was outside the confines of the cage. Stainless steel was the preferred metal for case construction. Photographs and working drawings of cages for mice, rats, guinea pigs, rabbits, and goats, and several types of metabolism cases are included in this paper. Cage decontamination was accomplished with the aid of complexing agents such as citric acid or sodium tartrate. Under certain conditions, nitric acid was used.

From abstract: "Electrolysis of cerium chloride or fluoride in the potassium chloride-lithium chloride eutectic mixture, or of cerium chloride in the calcium fluoride-lithium fluoride eutectic at 850° to 1000°C produces cerium metal in clean ingots in up to 80 per cent yield. Losses are chiefly due to oxyhalide formation in the presence of oxygen."

From abstract: "A theory of the sublimation of solids is presented and compared with experimental data on UCl4."

The document consists of two photographs and ten drawing of an electrolysis assembly for electroplating radioactive samples and one drawing of a thin-window Beta-counter. Included are a cell support, an electrolysis cell, electrolysis cell cathode, cell rack, Geiger counter absorber slide, carrier for electrolysis cell cathodes, and a cover for electrolysis cell cathode carrier.

Abstract: Most of the acute deaths among rabbits after single total-body x radiation occur in the first two days or at 10-15 days after irradiation. Signs of clinical depression are seen in survivors of sub lethal doses during each of these periods, termed the initial shock period and the principal acute radiation period.

Description of a velocity analyzer (with diagrams) is given. It is a device for measuring the velocities of charged particles which comprises pairs of spaced electrodes, a collector for charged particles, and means for propelling charged particles in a direction so as to pass between the pairs of electrodes. The pairs of electrodes and the collector are so arranged to permit passage of the charged particles between them to the collector plate. Means are provided for applying an alternating substantially square wave potential of known frequency to the pairs of electrodes so that adjacent pairs are opposite in phase and so that one half-cycle of the wave appears as zero potential between the pairs of electrodes.

Abstract: The output signal of a linear accelerator may have a rise time of 1-2 x 10[minus]7 seconds. Therefore, the output of a pulse height selector operating on this signal has a variation of delay from the original signal of about this amount. In the instrument to be described in this technical report this difficulty is largely resolved.

Abstract: Although we are generally interested in nuclear resonance levels, our measurements on Mn55 (naturally occurring Mn is 100 percent Mn55) were undertaken in order to corroborate Goldhaber's discovery of an extremely large scattering by this element.

Abstract: Equations are given to calculate at least approximately the heating in solid and hollow cylinders, slabs and spheres. Short and long cylinders are treated as well as short and long solenoids. The complicated mathematics used to derive the equations given will be omitted as they may be found in the original references. Heating with a spark gap converter is covered. Equations are given which together with some experimental data should enable the reader to predict the efficiency, heating, or temperature to be expected as the charge or coil is changed. Units and conversion factors are mentioned briefly.

This report proposes a method by which the amount of carbon in organic compounds containing fluorine can be analyzed and determined. The report includes a description of the apparatus and reagents necessary and a description of the procedure as well as a discussion of the results.

From foreword: "Construction of some typical ionization detectors and their operation, with most developed at the Los Alamos Laboratory and a few at other projects connected with the development of the atomic bomb." This report includes chapters 8-16 and an appendix to the second part.

Abstract: In order to calculate the difference between the number of neutrons which cross the x = o plane before and after the channel has been introduced we consider the number of neutrons which cross an element of cylinder wall at a height x1 and in a direction between (see Figure 5).