Nuclear processes are random in character, and, accordingly, are amenable to statistical treatment. In 1905, shortly after the discover of natural radioactivity, E. Von Schweldler showed that the analytical description of the decay distribution of radioactive substances followed from probability considerations regardless of the mechanism involved in the process of atomic disintegration.

"This report describes two experiments performed in an effort to supply evidence for the universality of the V-A theory in weak interactions and for the law of conservation of leptons. In this first part the production rate of B to the 12th by the absorption of negative mu mesons in carbon was measured. From the amplitudes of the muon decay curve and the boron decay curve the rate was calculated to be (5.8 plus or minus 1.3) x 10 to the 3rd sec -1, in agreement with the hypothesis of a universal V_A theory. In the second part an attempt was made to measure the helicity of negative mu mesons by stopping longitudinally polarized muons in a carbon target and observing the electron asymmetry in the β-decay of the spin-1 B to the 12th. The results of this part were inconclusive, a consequence attributed to a short boron thermal relaxation time."

"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 1935, Yukawa proposed that a field must exist, analogous to the electromagnetic field but different in nature, which is responsible for the attraction between a proton and a neutron in a nucleus. He was led to the prediction of the existence of particles, quanta of this field, with mass intermediate between that of the electron and proton. In 1947, using photographic plates, the Bristol group led by Powell confirmed the existence of these particles, meons."

"The design of the nuclear track intensifier was further analyzed to compare performance with design objectives. A preliminary analysis of the electron optics showed that the tube design suffers a small degree of astigmatism, which is increased in actual tabes by misalignment of parts, One tube was successfully completed and tested. Transit time of electrons from cathode to screen was determined to be 2.5 x 10/sup -8/ sec, 0.5 x 10/sup -8/ sec. Decay characteristics of several standard phosphors were measured. In the phosphor development phase, a latin square test was designed to evaluate combinations of thallium-activated rubidium iodide and cesium iodide phosphors under various evaporating conditions. Data were taken on various tests and analyzed statistically. On target samples submitted for tube evaluation, a reaction, which reduced light output, occurred between the aluminum and phosphor during vacuum bake. Oue image tube prepared with an alkali iodide mixture showed 10 to 25% improvement in screen resolution as compared to a P-11 screen."

"Development of a nuclear track image intensifier which is to have a cathode dia. of 83 in. and an output screen dia. of 1 in. is reported. Spherical faceplates for the intensifier which were etched to a thickness of 0.025 in. over a dia. of 80 in. withstood a pressure differential of 2 atm. Techniques were developed to measure spectral energy distribution, phosphor burn characteristics, phosphor efficiency, and phosphor persistence. Thallium- activated RbI and CsI were evaluated for use in the first stage of the image intensifier system. A color shift toward the yellow was accomplished in rubidium iodide phosphor by increasing the mole % of Th activator. Burn varied widely in different samples."

"Design and fabrication techniques were improved so that the large area image intensifier now performs well in image intensifier systems for photographing nuclear tracks. Two successful samples meeting most of the objectives were completed and started in circulation among members of the AEC Image Intensifier Committee for evaluation in systems to record nuclear tracks. Except for a reported long decay in the P-15 phosphor performance was quite good. Resolution, gain, and background requirements were met. Magnification was still high (1/6.5 compared to a design objective of 1/8) but can be lowered to 1/8 by a straightforward mechanical change. Evaporated layers of thallium activated rubidium and cesium iodide were improved and further evaluated. Improved control of color and persistence was obtained. Efficiency as high as 1/3 that of P-11 phosphor was obtained in some samples. The current test series confirmed earlier results that an increase in cesium iodide content shifts the emission spectrum towards the yellow. Burn-resistance and light output was poorer for the cesium enriched phosphors while decay time was decreased.

"The grafting of methacrylic acid, styrene (2: 1 mole ratio) co-monomer mixture on polypropylene film and fabric, was studied to compare electron accelerators and isotopes as sources of radiation. An aluminum block that contalns i/8-in.-deep pockets covered with Mylar film for holding sample and monomer during mutual irradiatlon was developed. A preliminary comparison was made in post grafting polypropylene film and fabric preirradiated with Cow and with an electron accelerator source. It was found that post grafting was rapid at 80 ts C but slow at room temperature. Monomer equilibration before irradiation increased the grafting rate. Higher grafts were obtained when samples were irradiated in sparged and sealed containers. The grafting rate increased as dose rate decreased."

"A finite difference approximation to a non-linear set of parabolic differential equations arising in shallow water theory is given. These difference equations were used to determine the shape and rate of propagation of a hum of fluid down a channel of constant depth. The hump of fluid was found to spread instead of steepen, as is the case in the usual shallow water theory."

"The loss of particles through a cusp of a particular containment geometry utilizing cusped magnetic field lies is considered. A velocity space loss criterion analogous to the loss cone in the mirror machine is derived. The effect of a uniform longitudinal magnetic field perpendicular to the containing field is considered and a loss criterion is derived. The effect of the longitudinal field is to decrease cusp losses.

"One of the fundamental concepts of macroscopic physics is that of a homogeneous system. The state of such a system is completely described by a set of intensive parameters which make no reference at all to the size or shape of the system, and by the total number of particles, N (unless otherwise specified we deal with one-component fluid). In actual systems, there are always inhomogeneities due to boundaries and to gravitational body forces."

"A comparison of the grafting of a 2:1 molar mixture of methacrylic acid and styrene to both polypropylene film and fabric using CO60 source and electron accelerator as sources of ionizing radiation is made on the basis of mutual or simultaneous grafting and post-irradiation grafting.

"A comparison of grafting to two thicknesses of polypropylene film is made using isotope and electron accelerator initiation. The results indicate that the grafting of methacrylic acid: styrene to polypropylene is mainly a surface reaction."

"Graft polymers were made by Co60 mutual irradiation of mixtures of styrene and methyl acrylate in contact Teflon. These graft copolymers were analyzed by infra-red absorption and their composition determined. The composition of the graft copolymer formed from styrene and methyl acrylate was different from that which is predicted by the copolymer composition equation."

"A brief examination of the post irradiation grafting of machine irradiated polyethylene film with acrylic acid monomer was made. Evidence of postgrafting was detected in samples that had been irradiated to a total dose of 10 Mrads at a dose rate of 0.01 Mrad/sec. and then exposed to a 25% purified acrylic acid solution in benzene for periods of 1 to 4 days."

"The influence of compressive creep on the self-diffusivity of α-iron has been measured in the temperature range of 742-885°C. the diffusivity is enchanced in proportion to the strain rate, but this dependence decreases with increasing temperature. The magnitude of the strain is relatively unimportant in this connection. Strain rates from 0 to -2 x 10¯³ sec¯¹ were investigated with a corresponding increase in diffusivity up to 3 x 10³ times. The results are analyzed in terms of vacancy diffusion and the excess vacancies introduced during deformation. It is concluded that grain boundaries are the main vacancy sinks in polycrystalline iron and that the vacancy lifetime is therefore dependent on the grain size."

COOLBALL is an IBM 650 machine program designed to calculate local gas and ball temperatures, gas flow, and pressure loses as induced by non-uniform power generation and voidage within an axial flow Pebble Bed Reactor core. This code has been used extensively to study the thermal characteristics of Pebble Bed Reactor cores in support of a broad program for the development of the PBR concept.

"The purposes of the program being conducted under the present contract are: 1) To determine the feasibility of cladding zirconium on uranium by a direct casting process. 2) To investigate the diffusion of liquid metals in the fusion zone."

"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."

"The problems of sequencing jobs through machines are discussed in a linear graph framework. The construction of feasible schedules from given technological orderings is related to the construction of transitive graphs from given component graphs. Methods of constructing transitive graphs are given and bounds on the number of different transitive graphs constructed from given components are determined. A recursive convex function defined on the transitive graphs-the job operation completion time and schedule time-is studied. Bounds on the number of different values that the schedule time can attain is obtained. Examples of multiprogramming, flow shop and machine shop scheduling are studied."

"Short-range order coefficients were measured at 300 and 400°C for iron-aluminum alloys containing 14.8, 18.2, and 20.0 atomic per cent aluminum. These alloys exhibited a strong preference for unlike near neighbors. The short-range order was greater at the lower temperature and increased as the Fe 3Al composition was approached."

"Theoretical calculations have been carried our for the two ordering phases which occur in the FeAl system. The statistical treatment involves first and second neighbor interaction parameters as well as a magnetic interaction between first neighbor iron atoms. The phase diagram and the amount and type of long range order for slowly cooled alloys are calculated. Further calculations include short range order for the disordered phase at three compositions and two temperatures. As expected, the short range order increases as a critical temperature is approached either in composition of in temperature."

"Equations for the heat-transfer coefficient existing at the interface of two metals in contact are discussed. The results of applying the equations (with a graphical determination of the geometric parameters) to an iron--aluminum contact are presented. A method is given for performing the graphical analysis by means of a general purpose analog computer. Data are included that were obtained by applying this method to Blanchard ground stainless steel surfaces in contact. Statistical analysis was applied to surfaces to determine the geometric properties of the contact as a function of root-mean-square roughness and method of surface preparation."

"An algorithm for the generation of feasible schedules and the computation of the completion times of the job operations of feasible schedule is presented. Using this algorithm, the distribution of schedule times over the set of feasible schedule—or a subset of feasible schedules—was determined for technological orderings that could occur in a general machine shop. These distributions are found to be approximately normal. Biasing techniques corresponding to “first come first serve,” random choice of jobs ready at each machine and combinations of these two extremes were used to compute distributions of schedule times."