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Hydrodynamic Theory of the Reaction Zone in High Explosives
From introduction: "The first part deals with stationary detonation waves...the second part is concerned with the structure of detonation waves of finite age...the third part deals with the steady state motion attained by a detonation wave in certain cases of two-dimensional flow."
The Statistics of the Hypocritical Water Boiler
From introductory paragraph: "In a slightly hypocritical water boiler the introduction of a single neutron may give rise to a fairly large burst of neutrons which dies out slowly. As was shown some time ago by Frankel and Nelson with the help of A. Horn the statistics of this multiplication process can be treated in a simple way for the hypothetical case that the number of neutrons produced per fission is two."
The Preparation of Tungsten Hexafluoride
From introductory paragraph: "Because of the possibility that tungsten hexafluoride might occur as an impurity in uranium hexafluoride it seemed worthwhile to prepare some of the material in order to become familiar with its mode of preparation, reactions, etc."
The Production of Fluorocarbons by the Reaction of Fluorine With Silicone Carbide
This technical report details the production of fluorocarbon by reactions between fluorine and silicon carbide. The report contains two figures depicting aspects of the process.
Comparative Effectiveness and Additivity of Fission Neutrons Gamma Rays and Beta Rays of Drosphila Eggs
From abstract: "Some investigations have been made to ascertain the similarity of the mechanism of action of radiation which are different in their specific ionization. A suggested approach was to determine if the energies absorbed from the different types of radiation are additive in their lethal effects on biological objects. In an attempt to determine the additivity of ionizing radiation various dose combinations of fast neutrons, gamma rays and beta rays were administered to Drosophila eggs. These test objects were chosen because their dimensions are such that they tend to absorb these three radiations uniformly throughout their volume. Although the three radiations were found to vary in their biological effectiveness, per unit energy absorbed, all three were shown to be completely additive in their lethal effect on these organisms."
The Quantitative Estimation of the Activity of Beta Particle Emitters
From abstract: "In estimating the activities of β-emitting materials used in the Biology Section, most measurements were made with Geiger-Mueller counters, although Lauritsen electroscopes were used in early work. All samples were mounted on flat porcelain capsules."
The Preparation of Cerium by Electrolysis of Molten Salts
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."
Capture Cross Section of Pb208 for C Neutrons
From abstract: "Using the method of induced radioactivity, the capture cross section of Pb[^]208 for C neutrons is found to be .00045 ± .00015 x 10[^]-24 cm[^]2. This is definitely lower than the value of .001 x 10[^]-24 reported by Maurer and Ramm."
The Rate of Sublimation of Solids
From abstract: "A theory of the sublimation of solids is presented and compared with experimental data on UCl4."
Identification and Crystal Structure of Barium Hydrogen Phosphate
From abstract: "The report describes the complete structure of barium hydrogen phosphate, Ba HPO4, as determined by means of x-ray diffraction. The crystal is orthorhombic, with cell dimensions given by a=5.71 A b=7.05 A c=4.61 A. The calculated density is 4.15gm/cm[^]3 for two molecules in the unit cell. The space group is C[subscript]2v[superscript]7-pmn. The barium, phosphorus, and two sets of oxygen lie in the plane of symmetry. The third set of oxygens are in general positions. Parameters for these atoms have been found, and interatomic distances calculated. The positions of the hydrogens are indicated by the characteristics O-H-O distance (2.58A) between two oxygens."
Report on Determination of Densities of Several Uranium Compounds
This technical report details a process in order to determine the densities of several uranium compounds.
Report on Methods of Preparation of Inorganic Fluorides
From abstract: "Frequently it has been desirable to prepare pure anhydrous metal fluorides. Several general methods have proved satisfactory depending on the type of fluoride to be prepared."
Methods of Analysis of Fission Products in the Experimental Biology Section
From abstract: "This report describes methods used for radiochemical analysis of fission products most used in the Experimental Biology Section. The report includes methods of analysis of Sr89, Ba140-La140, Zr95-Cb95, Ce144-Pr144, and Y91 by standard chemical procedures. In addition, a method of analysis by use of an absorption curve is described in some detail for Zr95-Cb95 mixtures. The absorption curve method makes possible rapid determination of percentage composition of a mixture of isotopes with a minimum of chemical manipulation by utilizing the differences in absorption characteristics of the emitted rays."
Sid Magnet Model Test Results
From introduction: "These data were taken on a 1/16th scale model of the magnet shown on sketch no. FS-2. The object of these measurements was to get information that would determine the final design of the full scale magnet. The one main point to be settled was whether a tapered or a cylindrical pole piece would give the largest value of Hρ for a given power input into the magnet (the cylindrical pole piece is shown in dotted lines in sketch FS-2)."
The Geochemistry of Columbium and Tantalum
From abstract: "This is a review, with annotated bibliography, of the mode of occurrence of the elements columbium and tantalum. It is not a list of specific ore deposits, but a summary of the types of minerals and rocks in which these elements have been reported to occur. In addition, the unpublished spectrographic studies of the Geological Survey are summarized, best sources for columbium and tantalum are indicated, and suggestions are made for further investigation."
Geochemistry of Germanium
From abstract: "This is a review, with annotated bibliography, of the mode of occurrence of the element germanium. It is not a list of specific ore deposits, but a summary of the types of minerals and rocks in which germanium has been reported to occur. Best sources for germanium are indicated, based on the data in the literature and on the unpublished spectrographic studies of the Geological Survey on mill and smelter products. Suggestions are made for further investigations."
The Metabolism of Thorium, Protoactinium, and Neptunium in the Rat
From abstract: "The distribution of carrier-free thorium, protoactinium and neptunium in the rat following intramuscular and oral administration has been studied. Oral adsorption for all three is negligible. Following parenteral administration, the skeleton is the organ showing the highest degree of prolonged and selective localization."
Capture of Fast Neutrons by Pb208
From abstract: "Comparison of the activity produced by fast neutrons on lead with other activations corroborates the assignment of the 3.2 hr. activity as Pb209, and the assignment of the reaction as capture of fast neutrons. Two different measurements show that the neutrons captured have energies greater than 100 KEV. This average capture cross section for primary neutrons from 7.5 MEV deuterons on a thick target of beryllium is measured as 10[^]-27 ca[^]2."
Electrolytic Reduction of Uranyl Ion
From introduction: "Due to the hydrogen overvoltage at the surface of a mercury cathode, uranium solutions is hydrochloric acid may be reduced not only to the tetravalent state, but until considerable trivalent uranium is formed. Other metallic ions act as oxidation-reduction catalysts as well as being reduced themselves. The following paper is a study of the various reactions taking place in solution and at the surface of the cathode."
Infrared Spectrum of Benzene
From abstract: "Benzene shows weak absorption bands in the 3 aliphatic C-Z region of the spectrum. The peaks of these bands are at 3.439, 3.459, 3.504, and 3.545."
The Crystal Structure of Ba3(PO4)2 and Sr3(PO4)2
From introduction: "This article gives an account of the determination of the complete crystal structures of the normal orthophosphates of barium and strontium."
Metabolism and Distribution of Inhaled Plutonium in Rats
From abstract: "Several different techniques were used to introduce tracer quantities of plutonium into the lungs of rats. When aerosols were produced by atomizing aqueous solutions of the nitrates it was found that approximately 20 per cent of the dose was absorbed and deposited in the skelton [sic] with tetra-, hexa-, and trivalent plutonium. Thus with these compounds, the lungs represent a more dangerous portal of entry than either oral (0.05 per cent) or intramuscular (13 per cent) administration. Tetravalent Pu was eliminated most slowly from the lung, the average half-time during the first month being 15 days. But when citrate was added to complex the Pu, over 70 per cent was eliminated within 1 day. This was accompanied by a deposition of over 30 per cent in the skelton [sic] and over 20 per cent in the liver. Presumably citrate breaks up the insoluble colloid in which Pu exists in the lungs. Complexing with cupferron which, unlike citrate, produces a "fat soluble" compound, greatly diminished the extent of absorption from the lungs. Plutonium oxide smokes which were produced at high temperatures were eliminated more slowly from the lungs (average half time of 30 days during the first month) and were deposited in the skeleton to a much lesser extent (6.2 per cent) than was the case with the nitrates."
Argonne National Laboratory Biology Division Quarterly Report: August to October, 1946
From introductory paragraph: "This is the first quarterly report of the Biology Division of the Argonne National Laboratory. During the three-month period covered by this report, a large share of the time of many investigators has been spent in collating work done under the Biology Section of the Metallurgical laboratory for publication in the Plutonium Project Record. The large amount of work done under wartime pressure has made this, as in other divisions and projects, an important part of the transition to the post-war period."
The Chemical Effects of Nuclear Transformations
This technical report is divided into two sections addressing two different chemical effects of nuclear transformations. The first section discusses the beta decay of lanthanum to cerium. The second section discusses the beta decay of selenium to bromine.
The Effects of Fast Neutrons on the Ability of Mice to Take Forced Exercise
From abstract: "In an attempt to gain some insight into the physiological condition of mice surviving massive doses of radiation, a study of their vitality was undertaken. It was assured that the ability of these animals to do forced work would be a measure of their vitality, Stimulating exposed animals to run in exercise wheels to their fullest capacity, has resulted in a demonstration of a striking vitality less during a post-irradiative period, when no other effects are demonstrable by gross examination. Mice subjected to a medium-lethal dose of fast neutrons show a continuous vitality loss over a 300 day period following exposure. Control animals show no appreciable loss of vitality up to about 8 months of age, after which a gradual loss can be noted, probably due to a normal gereologic process."
Slowing Down of Neutrons
From introduction: "The Boltzmann equation expressing conversation of particles in phase space is set up."
Drawings of an Electrolysis Assembly
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.
Physiological Observations on Rabbits Exposed to Single Doses of X-Rays
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.
Velocity Analyzer
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.
The Beta-Gamma Hand and Foot Counters
Abstract: This is basically a counting rate meter, with an alarm circuit, operating from four GM tubes as the detecting elements. The Hand Counter comprises four logarithmic counting rate meters working from four GM tubes mounted individually, with associated electronic circuits, in suitable shields with a metal mesh type of window. Both sides of both hands are sampled simultaneously. In the Foot Counter, two GM tubes are separately and mounted in a suitable mesh window shielded with the electronic circuit; the foot counter uses only two counting rate meters, and both feet are sampled simultaneously. Each circuit is built in two parts; two tubes are in the shield and the balance of the circuit is in the electronic unit which is a standard 17" x 13" chassis. Circuit diagrams are included.
Test Results on Bias Setting for the Chicago Scaler Offner Models
Abstract: The counting accuracy of the Chicago Scalers, Models 961A and 961B, is a function of the bias setting of the limiter (V2). this report gives quantitative data supporting this thesis. A method of making bias settings is suggested. These tests were run at the suggestion of Mr. V. C. Hanson.
Physical Properties of Uranyl Sulfate Solutions
Abstract: Measurements are reported of the solubility of uranyl sulfate in water at several temperatures, of the density of uranyl sulfate solutions as a function of concentration, of the variation of density of uranyl sulfate solutions of three different concentrations over a temperature range from 0[degree]C. to about 93[degree]C., and of the pH of uranyl sulfate solutions as a function of concentration as well as of temperature. The pH measurements were taken on uranyl sulfate samples prepared in several different ways and some conclusions are drawn as to the purity of theses samples.
Test Results on Clinton Alpha Amplifier Used with an Offner Columbia Scaler
Technical report describing development of the Clinton alpha amplifier. The circuit for the Clinton alpha amplifier which is used with an Offner scaler is shown attached to the report. It consists of a pre-amplifier mounted in a cylindrical alpha chamber, followed by a three state amplifier and a pulse height selector in a separate cabinet. Pulses are fed from the pulse height selector in the amplifier to the input tube of the Offner scaler. Through the third stage of the amplifier, this circuit is exactly the same as the California circuit now used by the chemical section for alpha counting. A type 961 Offner scaler was used for these tests. None of the latest Offner scalers type961A, were available to us when the tests were made. Method of testing is given, results are tabulated, computations are made, and eight graphs are given. it appears that the Clinton amplifiers used with a Offner scaler will give substantially the same performance as that given by the California circuit.
Manufacturing Specifications for the Higinbotham Scaler
Technical report which includes a description of scaling action in a Higinbotham circuit, of operation of the output circuit, of operation of the regulated high voltage supply. Acceptance and performance specifications are given. also included are cuts showing the bottom and top view of a scaler of this type. The scaling circuit diagram and major parts list is attached. To facilitate testing, the circuit of a satisfactory pulse generator is included together with a cathode - follower.
A Fast Coincidence Circuit with Pulse Height Selection
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.
Resonance Scattering of Neutrons by Mn55
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.
High Frequency Induction Heating
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.
The Spatial Distribution of Neutrons Slowed Down by Elastic Collisions
Technical report discussion of the complicated problem of the spatial distribution of slowed down neutrons. The introduction covers the current research on the topic. The following chapters cover the topics: (1) approximate treatment and its limitations, (2) age-velocity distribution, (3) general scheme of treatment based on transport equation, (4) Fermi's one-dimensional model, (5) moments, (6) remarks about the distribution function, and (7) point source.
Nucleonics and the Chemical Engineering Curriculum
This report discusses the field of nucleonics in the wake of the development of the atomic bomb, ruminating on the training and curriculum necessary for the next generation of chemical and nuclear engineers.
Pile Kinetics
From abstract: "A pile will run steadily at an arbitrary level if it is just critical. For a pile not at equilibrium, equations of motion can be set up that contain as variables the pile power, the number of delayed neutron emitters and, in case it is of importance, also the pile temperature. The coefficients will depend on the average lifetime of the neutrons in the pile, the fractions and periods of delayed neutrons, temperature coefficients of resistivity and similar quantities. For a definite 'excess resistivity', which may be positive or negative, the power level will change exponentially with time with periods determined by the so-called 'labour' relation. For control and safety problems the transient behavior of the pile under reactivity changes has to be investigated. A number of limiting cases can be solved explicitly. A general method for the solution of the pile equations is available for small deviations from a steady state. In this case a pile impedance can be defined in close analogy to electric circuit theory."
Theory of Pile Control Rods
From abstract: "A control rod absorbs neutrons and increases the leakage of neutrons from the pile through the depression of the neutron density in its vicinity. To determine the effect of controls on critical conditions for a pile the absorber may be considered, as in the electrical analogue, to produce a singularity in neutron density at its position. The strength of such a singularity is determined by the boundary conditions which must be satisfied at the surface of the black or non-black absorber and the order of the singularity is determined by the geometry of the problem. The general solution of the pile equations can then be expressed by a sum of a regular solution plus the solution containing the proper singularities and this total solution can be adjusted to satisfy the boundary conditions. By this means the effect of control rods of various sizes and positions on pile reactivity and neutron distribution and the effects of mutual control rod shading have been investigated both by a thermal and by a two group theory."
A Mass Spectrograph for the Analysis of Fission Product Mixtures
From introduction: "The analysis of mixtures of fission products with a mass spectrograph offers certain advantages. A chemical separation of the fission products found in the solution at Hanford is not necessary with the mass spectrograph technique. A sample of the mixtures can be placed on the sample holder and then the sample holder is mounted in the mass spectrograph. This reduces the amount of handling of the active solutions to one relatively simple and short operation. The health hazards involved in the analysis can be further reduced by increasing the efficiency of the spectrograph as much as possible, thus making possible an analysis of a sample of lower total activity. The mass spectrograph described here is an attempt to realize the advantages pointed out above. Particular attention has been given to increasing the increasing the efficiency of the instrument."
Determination of Carbon in Halohydrocarbons Containing Fluorine
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.
A Colorimetric Method
From abstract: "This paper gives a method for determining Uranium using sodium cresotate as a colorimetric reagent. A precision is obtained of better than 2%. In carrying out analyses for Uranium in corrosion products by existing methods such as ignition to the oxide, silver reductor, or titration with ceric sulfate, it became apparent that a rapid, fairly accurate method for determining uranyl ion would be of great value. Such a method is described in this paper. The most logical color to use is that given by the ferrocyanide complex, but upon studying this, it proved to be unsatisfactory. Sodium salycilate also gives a color which has been used with some success, but its color appears to fade and is not very sensitive. A similar compound, sodium cresotate, was found to give an orange-red color and is the reagent used in the method to be described."
Measurement of Density of Liquid UF6
This report describes a method and apparatus used to determine the density of liquid sodium hexafluoride. The report includes a drawing of the density cell used in the experiment.
The Thermal Conductivity of Liquid UF6
From introduction: "The measurement of the thermal conductivity of liquid TF6 presented unusual difficulties because of two of its properties which necessitated working with a closed system. The properties were (1) the liquid can exist as such only above 64.05°C. at which temperature its saturated vapor pressure is 1140 mm. of mercury, and (2) the compound reacts rapidly with moist air. Also because of the liquid's extremely corrosive nature, it was necessary to design a cell of special corrosion resistant materials."
Process Monitor, Mark 10, Model 20
This report describes a specific apparatus used to monitor the intensity of gamma radiation. The report includes a diagram of the apparatus.
Range of U235 Fission Fragments in Photographic Emulsion
From abstract: "A fine-grain emulsion has been found which is sensitive only to the densely ionizing fission fragments. This emulsion was soaked in uranyl acetate and exposed to slow neutrons. The ranges in the emulsion of about four-hundred fission fragments were measured. The resulting distribution shows a sharp maximum at 23 microns of emulsion. No ternary fissions or large-angle scattering of fragments were observed."
Measurement of Weak Neutron Intensities by Szilard-Chalmers Reaction in Calcium Permanganate Solution
From abstract: "A sensitive method for measuring the intensity of weak neutron sources by measuring induced Mn56 beta activity after concentration by a Szilard-Chalmers process has been developed. The practical detection efficiency for Ra-Be neutron is 7.8%; the procedure is capable of detecting a neutron intensity of about one neutron per second."
Inorganic Separations Using Ion Exchange
From summary: "In previous project work, dilute mixtures of inorganic cations in aqueous solution have been concentrated by adsorption of the cations on a synthetic resin and they have been fractionated by selective desorption of the cations from the resin. In this report..the general procedure used in chemical separation, the equipment used, and the theory of the exchange equilibria and of the reaction rates are presented."
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