"Time of flight spectrometers for the study of neutrons emitted in charged particle reactions have become important in recent years, following the development of suitable photomultiplier tubes and electronic circuits for nanosecond (ns) timing measurements. The principle of operation is simple. The particles exciting the nuclear reactions in which the neutrons are produced fall on the target in bunches of the order of a nanosecond in width. the arrival of product neutrons at a organic scintillation counter (proton recoil) detector placed a few meters from the target gives signals which can be used to determine the flight time of the neutrons from target to detector. A time-reference pule corresponding to the arrival of beam pulses at the target is required."

"Rates of acetylene polymerization induced by Kr/sup 85/ in d-c fields were up to 15 times greater than those observed when no fields were imposed. Work to determine the relations between acetylene pressure, Kr/sup 85/ concentration, and the field intensity is continuing. In other activities, equipment is being designed to study the effects of megacycle electric fields on radioinduced chemical reactions."

"As presented in the original proposal the project consisted essentially of three parts: Phase I, Development and refinement of a radiochemical flow counting technique for the study of kinetics of reactions in solution ; Phase II, The application of this technique to the detailed study of the mechanism of solvolysis of sulfonium salts in mixed solvents ; Phase II, The further application of this kinetic technique, as a longer term aim, to other reacting systems of biochemical or other interest. This report covers the work of the contractual period 1 Sept. 1959 to 31 Aug. 1960."

This report describes the design, construction and operation of a sub-critical nuclear reactor, intended for college teaching of reactor physics and of nuclear phenomena.

"A specific feature of the finite difference scheme proposed is that in it the boundary condition and the differential equation are treated simultaneously. The scheme results from a variational principle of the original differential equation problem, simply by using the Ritz method employing piecewise linear approximation functions. Thus a rather uniform treatment of boundary condition and differential equation will result. The coefficients of the substitute boundary condition will be given as the areas of sections of triangles cut out by the boundary; they are therefore not sensitive to variations of the direction of the boundary. An advantage of the approach is that the mean convergence of the solutions of the difference equations (including first difference quotients) to that of the differential equation is implied by the general theory and requires no special proof. Whether or not the scheme is useful in actual computation is still to be seen. The scheme for the Neumann problem of Laplace's equation is first described; then its extension to systems of second order is discussed. A lower estimate is given for the eigenvalues of the matrix involved. The method for extending the scheme to the Dirichlet problem is indicated."

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.

"An investigation was carried out on the possibility of increasing the light output of single crystals by applying an electric field throughout the crystal lattice. Pulses of frequency 2.5 x 10/sup 5/ cps were used with a voltage gradient of 10/sup 4/ volts/cm, and gamma radiation from Cs/sup 1//sup 3// sup 7/ and Co/sup 6//sup 0/ was used to excite the crystals. Tests were run on many types of scintillators. The visible light output was found to be increased by electric pulses for many of the scintillators, the best results being obtained with ZnS(MnCl/sub 2/, AgCl) crystals."

" A reliable, efficient and economical method is needed to remove radioactive halogens such as iodine and bromine and particulates from air in many atomic energy installations. One method we have developed which is particularly suited to reactor containment vessels or other large confined areas is foam containment. In this method an ether lauryl sulfate foam containing an iodine reactant is generated, rapidly filling the entire containment volume. This provides a tremendous surface area to which the encapsulated gases and particles can diffuse and be removed."

...Development during this quarter have caused a shift in emphasis of the Pebble Bed Reactor Fuel Element Development Program from coatings on the sphere surface to coatings on individual fuel particles as the major deterrent to fission product leakage. In a high level irradiation test, cracks developed in the coatings of specimens coated with pyrolytic carbon and siliconized silicon carbide. In another high level irradiation test, a graphite sphere fueled with Al2O3 coated with UO2 particles is showing excellent fission product retention. The leakage factors (i.e. rate of release/rate of production) for long lived volatile fission products such as Kr85m, Kr87, Kr88, Xe133, Xe135 are ranging from 10 to the negative 9th to 10 to the negative 6th. If this degree of fission product retention is maintained in a large power reactor, it would result in essentially a "clean" primary loop.

Previous results from the Pebble Bed Reactor Fuel Element Development Program had shown the excellent promise of vapor-deposited Al2O3 doq5intw on UO2 particles as a low permeability high temperature fission product barrier. However, since the matrix material for the PBR fuel element is a graphite sphere, carbonaceous coatings on the dispersed fuel particles might be of more interest because of improved particle coating-matrix compatibility and no displacement of neutron moderating materials. Since a pyrolytic carbon coating also appeared to be low permeability higt temperature material, emphasis was placed on the development of pyrolytic carbon coated UC2 particles dispersed in a graphite sphere as the reference PBR fuel element.

"A kinetic study is made of a system of neutral particles which interact under gravitational forces. The Jeans instability is recaptured in the limit of long wavelengths where the growth rate assumes a characteristic maximum value. As the wavelength diminishes to a certain critical distance, the instability vanishes. This distance is consistent with thermal-gravitational estimates for the diameter of a star. Plasma oscillations are found in the central region of a one-component charged gas cloud."

"The canonical (hamiltonlan) formulation of a relativistic dynamical theory is outlined, and the existence and explicit construction of general hamiltonian theories of relativiatic interacting particles are discussed. These hamiltonian theories are shown to contain certain elements of arbitrariness which are eliminated in manifestly coveriant formulations."

"Test results indicated that graphite is not suitable for seal face material. A program to evaluate various materials and seal face geometries was initiated. A seal run using nucerite-bearium combination was carried on for six hours."

"The full size seal (5 1/2" shaft diameter) was redesigned to incorporate the latest seal geometry which was developed as a result of the model seal test program. A number of compatible seal face material combinations, which performed satisfactorily during the model seal test program, was also selected for evaluation in the full size seal. All the detail drawings of the seal and test stand were completed. A test program for the full size seal was prepared and approved."

"The model seal test program was continued throughout the period covered by this report. Of notable mention, a test, 507 hours in duration, was conducted at 2000 psig and 2.75 GPH leakage. Examination of the seal faces after the test showed that there was no measurable wear within the limits of an optical inspection. The full size seal (5-1/2" shaft diameter) and the related test strand are in the manufacturing phase. The instrumentation and associated equipment for the full size seal test are on order."

"The model seal test program was concluded during this Quarterly Report. The final test, 1014 hours in duration, was conducted at a sea1ing pressure of between 2100 to 2300 psig and at a leakage rate of 2.14 gph. The seal face materials evaluated were an aluminum oxide rotor running against a stator face made of tungsten carbide for the high pressure seal and Graphitiar 39 for the low pressure element. Optical examination of the faces after the test showed no measurable wear. Nine unscheduled shutdowns were made during the test without damaging the seal faces or affecting the performance of the seal after each startup. The shutdowns were automatically accomplished in a predetermined sequence through a control system which was calibrated to monitor the test and stop it in the advent of equipment failure. The manufacture of the full size seal (51/2-inch shaft diameter) is 50% complete. All of the test equipment and instrumentation for the full size test rig has been received and assembled. The full size seal is scheduled for assembly by mid August 1963."

"The ion source used for hydrogen and deuterium ions in the variable energy cyclotron at the University of Rochester is of the hooded arc type. For the past year it has been operating with a new feature which has greatly improved its performance. The new feature is a magnetic mirror built into the upper end of the arc hood by a simple insertion of a steel bearing ball 1/8" in diameter. The magnetic field gradient near the ball provides a magnetic mirror action on electrons moving up the arc channel toward the ball, reflecting may of them."

"The hyperon-nucleon scattering is calculated for LAMBDA laboratory energies to 315 Mev. The potentials used were those linear combinations of the nucleon-nucleon potentials as prescribed by global symmetry. The mass difference between the LAMBDA - and SIGMA -hyperon was taken into account in the kinematics. The mass differences between the SIGMA -hyperons and between the nucleons are neglected. Angular distributions and total cross sections are given for all the possible hyperon-nucleon scattering reactions."

"The understanding of interactions between the elementary particles, which no number thirty, and range from the massless neutrino to the Е with a mass of approximately 1320 Mev, in a prerequisite to the knowledge of the structure of matter. Although the complex aggregate of elementary particles which constitute matter displays properties different from those of the basic building blocks, nevertheless it is impossible to gain a firm knowledge of the behavior of matter without first ascertaining in the intrinsic properties of elementary particles, as well as the dynamics of their interactions. The present work is concerned with inelastic proton-proton scattering at 1.35 Bev, where single pion production predominates."

"The previously found maximum in the cosmic radiation energy spectrum is discussed, and the possibility that it arises in part from a misinterpretation of the data due to oversimplifying assumptions about the composition of the beam is examined. The importance that lack of recognition of isotopic composition may have is pointed out, and it is clear that this importance is strongly dependent on the measurements made and on the cut-off rigidity."

"The properties of solutions of KI, AgNO/sub 3/, CoCl/sub 2/, and CoBr/ sub 2/ in anhydrous acetonitrile were studied by means of measurements of electric conductance, density, viscosity, and spectrophotometry. The data are examined in the light of theoretical concepts of electrolytes. The properties of acetonitrile as an ionizing solvent are discussed briefly, and a summary of existing information for inorganic salts in this solvent is presented."

"The interactions of 141 plus/minus 8 Nev n minus mesons with deuterium were studied using a 15 cm deuterium bubble chamber. The elastic differential cross section was measured by examining the angular correlation, range of positive recoil, and coplanarity of those scatterings which resulted in two outgoing charged particles. The accuracy of the measurement sin the backward hemisphere was on the order of 10-15 percent. This elastic differential cross section was compared to the results of impulse approximation calculations and they were found not to agree for backward scattering."

"Progress is reported in an evaluation of fission product concentration in rain as a function of time, location, and meteorological setting. Data on rainfall collected at Westwood, N. J., were analyzed for information on the mechanisms of fallout deposition, seasonal variations in fallout, the stratospheric residence time of W/sup 185/ resulting from Operation Hardtack, and the accuracy of pot samplers for sample collection. Data from other collection stations were also analyzed for consistency with Westwood data."

"A series of high urania-content glasses were fiberized and examined for high-temperature strength properties. One glass, RX360 containing 60% U/sub 3/O/ sub 8/ by weight, had better high-temperature tensile properties than any glass previously reported. It was observed that many of the glasses studied separated into immiscible phases and that the fiberizable glass phase had lower U/sub 3/O/ sub 8/ content than the base compositions. A physical analysis of crystal structures of the devitrification products from the nuclear fuel glasses indicated that most of the crystals consisted of uranium oxide in a reduced state. By adding O/sub 2/ to molten glass, it was possible to eliminate most of this devitrification. By elimination of crystals, the fiberizing of the glass was more uniform and the glasses produced had more consistent physical properties."