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Mathematics of Intermittent Irradiation
Initiation of reactions by intermittent irradiation is frequently encountered in physical, chemical, and biological systems. Mathematical expressions for transient and steady state concentrations of reactive species in these systems are useful for predicting performance and for research purposes. A general method of formulation of the intermittent irradiation problem is presented herein, and illustrative solutions are obtained for radioactive decay chains and for the rotating sector method.
Date:
March 12, 1963
Creator:
Hill, F. B.
Object Type:
Report
System:
The UNT Digital Library
Study of Low Frequency Molecular Motions in HF, KHF2, KH2F3 and NaH2F3
The spectra of KHF2, KH2F3, NaH2F3, liquid and solid HF were measured between 1200 and 30 cm-1 by the inelastic scattering of "cold neutrons" (0.005e.v.). The spectrum of KHF2 is in agreement with previous infrared measurements and shows a peak at 147 mV corresponding to a deformation frequency v2 of the F-H-F group and a broad peak at 13 mV due to a libration of this group. The observed spectra for KH2F3, NaH2F3 solid and liquid HF were compared with that for KHF2 considering the known results that the F-F distance increases, the position of the H atom between the two fluorines becomes more asymmetrical, and the strength of the hydrogen bond decreases in going from the HF2- ion to H2F3- ion to HF. In this comparison the known structure of the H2F3- ion is considered as being intermediate between that of HF2- and the zig-zag hydrogen bonded chains in solid HF. As a result, the lines observed at 112 mV and 67 mV in the H2F3- spectra and in HF respectively are associated with the deformation frequency v2 of the H-F-H group in these compounds. In addition the spectra of H2F3- ions show a peak at a 15 mV …
Date:
March 12, 1963
Creator:
Boutin, Henri & Safford, G. J.
Object Type:
Report
System:
The UNT Digital Library
Ytterbium and Terbium Dodecaborides
The synthesis of several rare earth dodecaborides, isomorphous with UB12 and ZrB12, and crystallographic data for these phases were reported recently. The unit cells are face centered cubic with four formula weights of MeB12 per unit cell; the structures may be visualized in terms of boron atoms linked in a rigid three-dimensional network, with the metal atoms in large cubo-octahedral holes.
Date:
March 12, 1963
Creator:
La Placa, Sam & Noonan, Daniel
Object Type:
Report
System:
The UNT Digital Library
Hot-Atom Chemistry of the Solid StateL its History, Current Status and Future Prospects viewed in Relation to the Planning of Chemical Research Programs for New Scientific Establishments Centered about a Research Reactor
The History, Current Significance and Status of the Field Hot atom chemistry, like many other fields of scientific research, can trace its origin to a single experiment, that of Szilard and Chalmers, performed in 1934. This is true even though recoil effects had been known and used for a long time. Almost immediately Szilard and Chalmers put their discovery to practical use: they employed the recoil effect in ethyl iodide as a neutron detector and observed the γ,n reaction in beryllium. The ingenuity of Fermi soon provided the correct explanation of the chemical separation observed by Szilard and Chalmers, and Fermi's co-workers, especially D'Agostino put the effect to a further practical use: the preparation of radioisotopes in high specific activity. These Roman scientists carried out the first Szilard-Chalmers studies in solids (sodium bromate, chlorate, iodate, and perchlorate, cacodylic acid and potassium permanganate) and reported some quantitative results: for example a quite accurate recoil yield of 80% of the Mn 56 in potassium permanganate. Perhaps the most striking practical result of a Szilard-Chalmers experiment lay in the discovery, by Kourtchatow and co-workers, of the important isotope Br 82 in extracts from neutron-irradiated ethyl bromide.
Date:
March 8, 1963
Creator:
Harbottle, Garman
Object Type:
Report
System:
The UNT Digital Library
Human Radiation Injury - a Correlation of Leukocyte Depression with Mortality in the Japanese Exposed to the Atomic Bombs
The method of collection and the subsequent analysis of the hematological data accumulated by the Joint Commission of the Investigation of the Early Effects of the Atomic Bomb in Japan, have been described. In the present investigations, an additional analysis of the hematological data was made to investigate a possible relationship between leukopenia and the mortality rate within the first nine weeks following the bombings. It has been frequently observed in laboratory animals exposed to ionizing radiation that the extent of the fall in the white blood count reflects the dose of radiation received. Smith et al have demonstrated that in mice survival can be related to the depression of the granulocyte count at various times following radiation. Cronkite and Brecher and Cronkite, Bond and Dunham inferred that the hematological response could be used as a biologic dosimeter for exposed human beings. This report is concerned with the study of the response of the white blood cells to ionizing radiation resulting from the atomic bomb detonation in Japan.
Date:
March 8, 1963
Creator:
Jacobs, George J.; Lynch, Francis X.; Cronkite, Eugene P. & Bond, Victor P.
Object Type:
Report
System:
The UNT Digital Library
Long Coil Measurements Satisfy Two-Dimensional Field Equations
The amount by which the field of a magnet bends the path of a charged particle is proportional to the integral of Btds along the trajectory. Instead of making tedious point by point measurements of B in magnets and performing the integrations numerically, it has been found useful to measure directly, by using a search coil whose winding consists of long and narrow turns extending through the magnet gap from z1 and z2 in the direction of the trajectory. It should be noted that the integral Iy is taken along a straight x=constant, y=constant lines and not along the actual curved trajectory path; for small curvature the difference is small.
Date:
March 8, 1963
Creator:
Beth, R. A.
Object Type:
Report
System:
The UNT Digital Library
Neutron Sources - Cross Sections and Angular Distributions
It is appropriate that a conference devoted to the interactions of fast neutrons with nuclei begin with a survey of the available sources of such neutrons. Since its discovery in 1932, the neutron has provided a highly useful tool in attempts to understand the nucleus, and the types of nuclear phenomenon which could be studied and the nature of the results obtained are very dependent on the sources available.
Date:
March 8, 1963
Creator:
Goldberg, Murrey D.
Object Type:
Report
System:
The UNT Digital Library
Numerical Solutions for Diffusion in a Sphere, Cylinder, and Plate
In calculating diffusion coefficients for gases diffusing from solids, the numerical solutions tabulated by Darken and Gurry, were found to lack the required precision, and the intervals between the arguments were too great to permit precise interpolations. Consequently the diffusion equation solutions of interest (diffusion from a sphere, cylinder, and plate, for the condition that the concentration of the diffusing species initially uniform) were re-evaluated. Computer programs for the three cases were written in FORTRAN for the IBM 7090. The solutions programmed are given in Crank. Values of the fractional completion were computed at approximately 0.01 increments, to the nearest 0.00001, and are tabulated in Table 1 to the nearest 0.0001. The table covers the fractional range from about 0.04 to 0.99. For smaller fractions satisfactory approximations are available. The table may be conveniently interpolated by plotting points about the region of interest and drawing a curve.
Date:
March 8, 1963
Creator:
Auskern, Allan
Object Type:
Report
System:
The UNT Digital Library
Personnel Dosimetry of Very High Energy Radiation
Before discussing personnel monitoring of high energy radiations, it is appropriate to comment briefly on two basic methods of dosimetry applicable to such situations. In the first of these methods, one measures the rad dose in air with a tissue-equivalent ionization chamber that is operated with enough voltage on the collecting electrode to insure saturation even when the radiation is concentrated in short pulses, as is frequently the case. The linear energy transfer (LET) spectrum of the radiation is then determined and an average value of relative biological effectiveness (RBE) is determined. An experimental evaluation of the depth dose situation completes the data necessary for a full evaluation of the biological hazards. The method is completely general but is most applicable to situations where a substantial proportion of high energy components is present in the mixed radiation. It should be noted that the detailed composition of the radiation need not be known. Thus, components of dosage to which an RBE of 1 is assigned may be due to X-rays, gamma rays, or the ionization tracks produced by protons in the Gev energy range as well as by many other types of radiation. This method is applied frequently to the situation …
Date:
March 8, 1963
Creator:
Cowan, Fredrick P.
Object Type:
Report
System:
The UNT Digital Library
Structure of HCrO2 and DCrO2
A neutron diffraction study of polycrystalline HCrO2 and DCrO2 (chromous acid) is described. Intensity data from the two substances were refined together by the least-squares method, with the constraint that the Cr-O distance be the same in the two substances. Estimates of individual contributions to multiple peaks were included in the least-squares refinement through the use of a non-diagonal weight matrix. The O-D-O bond is found to be asymmetric, O-D = 0.96 ± 0.04 A, O...O - 2.55 ± 0.02 A. The symmetry of the O-H-O bond cannot be determined, but agreement with observation is as good with a symmetric bond as with any other model. The O-H-O bond length is 2.49 ± 0.02 A. These results are consistent with those from previous studies of the HCrO2-DCrO2 system by nuclear magnetic resonance and infrared techniques.
Date:
March 8, 1963
Creator:
Hamilton, Walter C. & Ibers, James A.
Object Type:
Report
System:
The UNT Digital Library
Theoretical Analysis of the Exponential Experiment in Natural Uranium
Methods of calculating the "Snell Experiment" (the exponential experiment in natural uranium) are examined. It is found that integral transport theory is required for accurate predictions. The effect of spatial transients upon measured quantities is studied and it is found that experiments have not been done in a large enough mass of uranium to achieve an asymptotic neutron distribution. However deviations from the asymptotic values of integral quantities are not large and corrections are calculated and applied to recent experiments. It is shown that the use of recent cross section data improves the agreement between theory and experiment. The relaxation length and all spectral indices are in fairly good agreement except for Np237 to U238 average fission cross section ratio.
Date:
March 8, 1963
Creator:
Michael, Paul
Object Type:
Report
System:
The UNT Digital Library
Radiation - Induced Mammary Gland Neoplasia in the Rat
In discussing this subject, data on radiation induced mammary gland neoplasia in the rat indicating that direct interaction between the radiation and target tissue is necessary for maximum neoplasia induction will be presented mainly. Other types of radiation induced neoplasia, in which little or no information on the mechanisms involved is available, will be discussed briefly. In particular, investigations on radiation induced mouse lymphoma will be reviewed, in which neoplasia appears to be an abscopal effect. Implications of these data will be discussed, particularly with regard to possible mechanisms involved, and extrapolation to man.
Date:
March 6, 1963
Creator:
Bond, V. P.; Cronkite, E. P.; Shellabarger, C. A. & Aponte, G.
Object Type:
Report
System:
The UNT Digital Library
The Radiation Processing Research and Development Program at Brookhaven National Laboratory
The generic term "chemonuclear" has been assigned to any chemical process system using nuclear energy as the prime energy source. The type of effect which induces the chemical change, or produces the chemical is of importance in classifying the type of chemonuclear process, or reactor involved. Four types of effects are identified for this classification. These are radiation, thermal, electrical, and photolytic effects. The radiation effects include the interaction with matter of high energy particles, or photons carrying energy in the range of a million electron volts (MEV) or higher, and causing primarily ionization effects. Thermal effects include transfer of thermal energy to matter and usually is directed towards producing a thermodynamic equilibrium in the system. Electrical effects are concerned with interaction with matter of particles carrying energy in the range of electron volts up to thousands of electron volts (EV to KEV). The photolytic effects utilize photon energy in the range of infrared through the visible to the ultraviolet radiation (IR, Visible, and UV). As is evident, this classification is somewhat arbitrary since it is primarily based on a division of the energy spectrum which is in reality continuous. It does, however, separate the more conventional methods of inducing …
Date:
March 6, 1963
Creator:
Steinber, Meyer & Manowitz
Object Type:
Report
System:
The UNT Digital Library
Secondary Tetanus Antitoxin Responses in Mice Elicited Prior to Irradiation
The pioneer study by Benjamin and Sluka in 1908 on inhibition of antibody formation by X-rays revealed the importance of the temporal relationship between exposure to radiation and injection of antigen. X-radiation delivered three days before injection of beef serum inhibited precipitin formation in rabbits. A similar exposure to X-rays delivered three days after injection of the antigen failed to repress production of specific antibody. These observations were partially confirmed in 1915 when Hektoen reported inhibition of hemolysin production in the rat when X-radiation was delivered either before or after injection of sheep red cells. Although an absolute difference in radiosensitivity was not evident, the depressant effect of radiation on antibody production appeared to be less effective when radiation was given after injection of the antigen.
Date:
March 6, 1963
Creator:
Hale, William M.
Object Type:
Report
System:
The UNT Digital Library
Joint National Institute for Health-Atomic Energy Commission Zonal Centrifuge Development Program, Semiannual Report for Period July 1 - December 31, 1962
This technical report describes development work done on zonal centrifuge systems at the Oak Ridge National Laboratory and the Oak Ridge Gaseous Diffusion Plant during the period July 1 to December 31, 1962 under the Joint National Institute for Health-Atomic Energy Commission Zonal Centrifuge Development Program. A basic purpose of this project is to develop new methods for isolating virus particles associated with cancerous cells and tissues. Three classes of rotor systems capable of separating particles ranging in size from whole animal or plant cells to protein or nucleic acid molecules on the basis of either sedimentation rate or density alone have been developed. Experiments with phage particles indicate the feasibility of large-scale virus isolation by continuous-flow centrifugation, followed by isopycnic banding in cesium chloride and velocity sedimentation in sucrose - all steps being carried out sequentially in the same rotor. Zonal rotors using the reorienting gradient principle for molecular separations have been tested to 141,000 rpm (formula). Previous work on zonal centrifugation and future plans for this program are discussed.
Date:
March 4, 1963
Creator:
Anderson, N. G.
Object Type:
Report
System:
The UNT Digital Library
Alternating Gradient Magnets
The angle by which a magnet deflects the trajectory of a particle in the x-z plane is proportional to the integral [integral not transcribed] taken over the trajectory wherever B≠0. Alternating gradient focusing is achieved by designing magnets so that I=I(x) varies linearly with x over a suitable x interval. Usually this is done by shaping the poles to give a linear variation of By with x while keeping the length of the magnet constant for different x. Certain advantaged may be gained by varying the effective length of the magnet with x and keeping By constant so that the integral varies properly with x. Figure 1 shows several such poles for which the trajectory length, and hence the integral (1), varies approximately from 2/3 to 4/3 of the mean value.
Date:
March 3, 1963
Creator:
Beth, R. A.
Object Type:
Report
System:
The UNT Digital Library
Aeroradioactivity Survey and Areal Geology of the National Reactor Testing Station Area, Idaho (ARMS-I)
Report regarding an airborne radioactivity survey that took place in the 10,000 square mile area surrounding the National Reactor Testing Station in Idaho Falls, Idaho. Topics include the types of bedrock noted in the area as well as their levels of radioactivity.
Date:
March 1963
Creator:
Bates, Robert G.
Object Type:
Report
System:
The UNT Digital Library
Analog Computer Studies of the ML-1 Power Plant
From introduction: The main objective of the AGCRSP is to develop plans and specifications for a mobile nuclear power plant suitable for military field use.
Date:
March 1963
Creator:
Calamore, D. V.; Crimmins, D. H. & Tobey, E.
Object Type:
Report
System:
The UNT Digital Library
Crystalline Field Splittings in Holmium and Dysprosium Ethylsulfates
From report : "It has become apparent that pragmatic resonance data alone are insufficient to correctly evaluate crystal field parameters for rare-earth ethylsulfates, and that heat capacity data above 20°K are a useful aid in determining whether low lying levels obtained by absorption spectroscopy have been correctly identified."
Date:
March 1963
Creator:
Spedding, F. H.; Gerstein, B. C.; Haas, W. J.; Phillips, E. & Sutherland, W. L.
Object Type:
Report
System:
The UNT Digital Library
EVESR Nuclear Superheat Fuel Development Project: Third Quarterly Report, December 1962-February 1963
Quarterly report describing progress on the EVESR Nuclear Superheat Fuel Development Project.
Date:
March 1, 1963
Creator:
Pennington, R. T.
Object Type:
Report
System:
The UNT Digital Library
Gamma Activities in Irradiated Beryllium Oxide
The major long lived activity induced in irradiated Pechiney and Brush BeO specimens is due to Se-46 arising from scandium present to the extent of about 1 p.p.m. The Brush specimens showed additional activities due to Fe-59 and Co-60 and to Cr-51. The levels of Cr-51 found are considerably higher than would be expected on the basis of stated chromium impurity levels suggesting that the chromium is introduced during handling of the samples on site. Approximate values of the dose rate are included.
Date:
March 1963
Creator:
Green, R. M.
Object Type:
Report
System:
The UNT Digital Library
Grinding Studies on Beryllium Oxide Powder
Inhomogeneities in Brush UOX beryllium oxide observed in the powder and in cold pressed and sintered specimens have been removed by grinding the powder prior to fabrication, all grinding procedures reduced the densities obtained under standard sintering conditions, but some grain refinement was noted on sintering after short grinding periods. These effects are related to the introduction of alumina and silica impurities during ball milling. There is some indication that short grinding periods improve the strength of sintered specimens.
Date:
March 1963
Creator:
Reeve, K. D. & Ramm, E. J.
Object Type:
Report
System:
The UNT Digital Library
High Temperature Short-Time, Uranium Carbide-Metal Reactions
Report investigating the compatibility of uranium carbide with tungsten, tantalum, molybdenum, Zircaloy-2, AISI 304L SS, Inconel, Hastelloy F, niobium-1% Zr, and niobium-33% Ta-1% Zr. These pairs were heated together at 1000 C and above for ten minutes.
Date:
March 1963
Creator:
Christensen, J. A.
Object Type:
Report
System:
The UNT Digital Library
The Hydrolysis of Orosomucoid with Trypsin
In recent years a good deal of understanding about the structure of the α-acid glycoprotein of human plasma (orosomucoid) has been obtained. Since the isolation of the protein in an apparently pure state, it has been shown to have a molecular weight of approximately 45000 and to be made up of about 40% carbohydrate and 60% polypeptide. The latter apparently is in the form of a single polypeptide chain. The carbohydrate, on the other hand, has been shown to have at least 16 non-reducing chain ends terminating in sialic acid, and may also have 1-3 further chains with fucose on the non-reducing end. At least in those chains terminating in sialic acid, galactose is in the next position followed by N-acetyl glucosamine. The recent report of the isolation, from a partial acid hydrolysate of the α-glycoprotein, of an octasaccharide containing 2 residues each of galactose and mannose, and 4 residues of N-acetylglucosamine, indicates that at least part of the carbohydrate in the protein is the form of units no smaller than this. However, the number and nature of the firm covalent linkages between carbohydrate and protein remain uncertain, and it was for this reason that the present study was undertaken.
Date:
March 1963
Creator:
Popenoe, Edwin A. & Mendelsohn, Naomi
Object Type:
Report
System:
The UNT Digital Library