The coolant stream of all nuclear reactors caries some activity due to one or more of the following: a) neutron activation of coolant atoms, b) neutron activation of corrosion products carried by the coolant stream, c) fission recoil into the coolant stream, d) fission products leaking into the coolant stream. The Pebble Bed Reactor is not concerned with (1) and (b) since the helium working fluid, or coolant, has an activation cross-section which is essentially zero and its inert chemical nature effectively eliminates corrosion as a consideration. We are not concerned with (c) since developments to date, of fuel and particle coatings to reduce fission product leakage, will also prevent fission recoil into the coolant stream.

"The design, analysis, and selection of system components for functions related to secondary shielding and associated auxiliary systems for the Antarctic PM-3A Nuclear Power Plant are described. Backfill material characteristics, shielding and activation analyses, heat transfer analysis, backfill cooling system, water exclusion and removal system, and instrumentation and control are discussed."

"The natural exponential decay of a radioisotope used as a heat source for a thermoelectric generator makes the use of a power flattening'' device highly desirable, especially when the duration of the mission is large compared to the half-life of the radioisotope. Power-flattening devices are considered which either dump excess heat outside the thermoelectric generator or use the characteristics of the generator to absorb the excess heat and thereby regulate the hot junction temperature. A number of power-flattening devices were studied both analytically and experimentally with a view toward operability in space. The most promising concepts are (a) to utilize a secondary radiator of variable area; (b) to provide thermal shunts that are sequentially removed during the mission; (c) to use a secondary radiator coupled to the heat source through a slowly evaporating thermal connection."

"The lifetimes of approximately 6 million positive mesons have been measured using a crystal controlled oscillator as a clock. The resulting decay curve was analyzed on the IBM 650 digital computer and gave a mean life of 2,211 plus or minus 0.003 µsec. The mean life of negative mu mesons in carbon was also measured and found to be 2,043 plus or minus 0.003 µsec. The resulting nuclear capture rate is (0.373 plus or minus 0.011)x10 to the 5th/sec, assuming that the decay rate of a negative mu meson bound in carbon is equal to the decay rate of the positive meson."

"In our original proposal it was pointed out that we had obtained, b the successive treatment of adrenochrome with mineral acid and thiosemicarbazide, a black material which proved to be effective in preventing vascular damage cause by snake venom, radiation and thermal burns. Since the effectiveness of this preparation varied widely with different samples it was suspected that the product did not have a uniform composition. As a results of the inability of effect a separation or purification of the black product we decided to try some pure compounds related to adrenochrome. Some results obtained were reported in our proposal to renew contract AT(301\-1)-2242. Other results will be reported in the body of this report."

"Work accomplished in incorporating plutonium oxide in glass and glass fibers between July 1960 and March 1961 is summarized. The purpose of producing plutonium bearing glass and glass fibers was to eliminate or reduce the radiological and toxicological hazards associated with plutonium. Initial results using "wipe" tests showed no removable alpha contaminant in freshly prepared samples. Leaching studies were made using water, dilute HCl, and HNO/ sub 3/. The amount of PuO/sub 2/ leached from the glass can be greatly reduced by substituting Al/sub 2/O/sub 3/, CaO, and K/sub 2/O for much of the Na/sub 2/O component in the glass composition."

"Results of molecular studies showed that, depending on the chemical composition, polyphosphates are either linear or branched flexible chain molecules. The branch points were easily destroyed by hydrolysis. Hydrolytic stability studies showed that the rate constants are much smaller for the splitting of internal bonds than for the hydrolysis near the chain ends, where both monomeric and trimeric rings are formed. The kinetic study of the degradation of sodium pentaphosphate was continued. Preliminary results indicated that, in the absence of calcium, the formation of each trimeric ring is accompanied by the formation of two orthophosphate rather than one pyrophosphate molecule. The influence of different univalent cations on the behavior of polyphosphates was studied by electrophoresis, conductivity, membrane equilibrium, and viscosity measurements. The effects of divalent ions were also studied."

"Mathematical methods are being developed for calculations in fluid dynamics. The work to date on the Mach reflection calculation is summarized. In the flow, there are two curved shocks, a slip surface, a plane shock, and rigid walls. The desired solution of the fluid-dynamics equations is stationary in similarity variables; approximate initial data are therefore assumed, with the expectation that the flow will settle down to the desired one asymptotically. The Eulerian equations for the smooth parts of the flow are coupled to the jump and boundary conditions on the various surfaces. Two-dimensional fitting procedures were devised to apply the jump and boundary conditions. All parts of the code now appear to operate satisfactorily except for the treatment of the slip surface, which showed instabilities after about 50-70 cycles. The main problem was temporarily discontinued, in order to concentrate on the slip surface. A simplified problem of a nearly plane slip surface between parallel walls and with periodicity conditions along the surface is described. This problem uses all the machinery of the main code except for the parts having to do with the shocks, and it has additional subroutines for computing an analytic solution based on the linearized theory of …

"The long wavelength modes of excitation of a two component plasma in a steady magnetic field are examined. Two linearized Boltzmann equations are given with collision terms which are coupled through the difference in temperatures and difference in velocities of the two gases. A formal means of classification of phenomena is described in terms of the nature of the roots about k = 0. Two types of behavior are uncovered: MHD, magnetohydrodynamics, which include finite phase speed phenomena near k = 0; and PEM, plasma electromagnetics, which includes infinite phase speed phenomena near k = 0. The dissipative effects of collisions are included. In the limit of vanishing collision frequency, roots previously obtained are recaptured. The relevance of the pertinent domains are discussed and the complex interplay between the fast and Alfven modes of MHD and the plasma- magnetic modes of PEM is demonstrated. Equations macroscopic in appearance are derived which include the effects of the initial configuration. In the limit of large collision frequency the equations reduce to standard forms. The dispersion of the Nth order Larmor resonance is given which includes the effect of the mass ratio. A discussion of the transfer equations of a plasma is included."

"As a part of a program to determine the p-p scattering matrix at 213 Mev, the triple scattering parameters R and A were measured at 30, 40, 50, 60, 70, 80. and 90 deg in the center-of-msss system. The results are compared with a phase shift analysis by MacGregor and Moravcsik and with the predictions of the boundary condition model of Saylor, Bryan and Marshak."

"The study of the single channel scattering problem was extended to include the multi-channel case. The scattering problem was formulated in a mathematically rigorous way which reflects the time-independent point of view but is not limited by any dependence on a configuration space representation. Wave operators were defined by an integral representation. When the conditions necessary for the time-dependent formulation are valid these wave operators will be identical to those defined by the asymptotic limits and will provide a solution of the scattering problem. But these conditions are stronger than those which are sufficient for a solution, so there should exist a class of Hamiltonian operators for which a solution of the scattering problem exists but for which the asymptotic conditions are not valid."

"The study of the toxicity of Ra and MsTh(Ra/sup 228/) in humans was continued. Several Thorotrast cases were also examined. Physical and clinical studies were made on 151 persons. In all cases possible gamma ray measurements were made of Ra and MsTh decay products retained in the body, alpha -ray measurements of Rn and Rn/sup 220/ in breath, a complete medical history was taken, a complete x-ray examination was made of the skeleton, and urinalysis, hematological, and blood chemistry studies were made."

"The study of the toxicity of Ra and MsTh(Ra/sup 228/) in humans was continued. Several Thorotrast cases were also examined. Physical and clinical studies were made on 151 persons. In all cases possible gamma ray measurements were made of Ra and MsTh decay products retained in the body, alpha -ray measurements of Rn and Rn/sup 220/ in breath, a complete medical history was taken, a complete x-ray examination was made of the skeleton, and urinalysis, hematological, and blood chemistry studies were made."

"A new 350 KV power supply was installed, and major modifications of the accelerator were completed. The changes include the installation of new focusing and extractor supplies, an extension of the accelerator column, and the replacement of the isolation transformer by a motor generator set. Improved performance at voltages up to 200 KV was obtained, but a modification of the electrostatic lens system will be required for operation at 350 KV. The results of an investigation of the C/sup 12/(n, alpha )Be/sup 9/ reaction and a search for an excited state in He/sup 5/ are discussed. Work in progress includes: N/sup 14/ and O/sup 16/ (n, alpha ) angular distribution measurements with counters; studies of I/sup 127/ (n,d)Te/sup 126/ using counters and I/sup 127/(n,p)Te/sup 127/ using emulsions; and the development of an E x dE/dx pulse height multiplier."

"The modified accelerator performed well at voltages up to 200 kv, and construction of a 350-kv acceleration tube was initiated. An all-solid-state telescope was completed, and a (dE/dx x E) pulse multiplier was almost finished. These instruments will be used with a new analyzer to permit simultaneous recording of (n,p), (n,d), and (n,t) spectra. An analysis of previous data on LiT/sup 7/d, alpha) He/sup 5*/ yields alpha + n showed that the first He/sup 5/ excited state is at 2.6 plus or minus 0.4 Mev with a width of 4.0 plus or minus 1.0 Mev. The intensity of the excited state relative to that of the ground state was found to be 1.45 plus or minus 0.50. Preliminary angular distributions for the N/sup 14/ (n, alpha) B/sup 11/ and O/sup 16/ (n, alpha) C/sup 13/ reactions were obtained Modifications were made to the counters for these experiments, and electronic equipment associated with the counters and detectors was constructed. (D.C.W.) Aluminum targets evaporated under a variety of conditions all showed a Lewis peak on the thick-target gamma-ray yield curves over the Al/sup 27/(p, gamma) Si resonance reaction at 992 kev. The peaks of all targets prepared at pressures below 4 x …

"The problems discussed are those encountered in assigning unequivocal emf values to electrode systems. Three electrodes which meet the requirements for reference electrodes most adequately are considered in some detail: these are the hydrogen, silver-silver chloride, and mercury-mercurous chloride (calomel) electrodes. An assessment is presented for electrode systems for aqueous solutions, organic solvents, fused slats and biological systems."

"A method for extracting information on Regge trajectories from experimental data in the analysis of highenergy, small-angle elastic scattering is outlined."

"This approach to the problem of radiation damage was reported. A comparison of haploid males and diploid females with respect to their radio-sensitivity was made at various stages of embryonic and post-embryonic development. Differences in sensitivity were observed and taken to indicate that genetic damage is involved in the effects of x-rays upon development in Habrobracon juglandis."

"The problem of explaining the lack of radiative muon decay in an intermediate charged vector meson theory is discussed. A possible way of introducing the charged vector meson to the theory of weak interactions is outlined in which renormalization is retained. However, if this way is used, the anomalous magnetic moment is calculated to be large, which is in contradiction with expectation."

"Properly designed and fitted respirators have been effective devices for reducing the inhalation of toxic aerosols. The degree of protection afforded by these devices has not been quantitatively measured under actual work conditions except by bioassay or other elaborate techniques. This report describes a new quantitative technique for evaluating over-all respiratory performance under conditions comparable to exposure to highly toxic radioactive materials such as plutonium and non-radioactive materials such as beryllium."

"Dust and gas masks and respirators have been an effective method under certain environmental conditions to reduce the inhalation of toxic aerosols. Under many conditions, however, their efficacy has been seriously questioned. It is the purpose of this study to evaluation over-all respirator performance on fine aerosols and to develop equipment whereby a greater degree of respiratory protection may be assured with reliability for highly toxic atmospheres."

"An experiment in which a nuclear emulsion stack of 25 Ilford G-5 emulsion pellicles were exposed to 925-Mev He^4 nuclei is described. The tracks of the He nuclei entering the stack were followed in the stack until they interacted or stopped. From the data the scattering constants for He^4 and He^3 were calculated."

The objective of the study which is being carried out under contract AT(30-1)-2477 is the exploration of all aspects of research in water resources and supply to determine the potential for using radioisotope technology in this research. Problem areas in the application of tracers in this research are being investigated through the evaluation of past experimentation with radioisotopic techniques and through discussions with those who are active in this work. A series of suggestions relating to these techniques will de drawn up to indicate which techniques should be developed further in order that more extensive applications may be found for them.

Room temperature tensile properties are given for a series of slip cast APPR-type UO2 stainless steel fuel plates. Properties of conventionally fabricated type SM-1 dispersion plates were determined for comparison. Slip cast fuel plates sintered to 90% density, hot or cold rolled approximately 30% and annealed 1 hour at 1120% showed ultimate tensile strengths equal to those of the conventional plates, slightly lower yield strengths, and tripled ductility.