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

"The laboratory experiments and field testing which were carried out in the development of a homogeneous gas labeling device are described. Detailed drawings of the injector and its most critical components are included. Recommendations are made for a production model of the device along with estimated costs of construction."

"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 APPR-1 is a pressurized water reactor having a low specific heat fuel and a water primary coolant. The primary coolant loop delivers heat from the reactor to the steam generator. The secondary water in the steam generator is converted to steam and then taken to the turbine to drive an electrical generator. The simulation of this system is broken down into three primary areas: the neutron kinetics in the reactor which are necessary to generate the primary power function, the heat transfer in the reactor, and the heat transfer in the steam generator.

"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 probability of accidents to tractor semitrailers is developed through analysis of accident frequency data in relation to season; geographical factors; road type, traffic, and population density; and type of carrier business. Maximum likelihood rates are developed for the potential carriers of radioactivity. Impact characteristics of accidents are studied through the analysis of mass, speed, and energy relations, and the effect of these on vehicle and cargo damages is explored."

"Mixed Fission Products (MFP) for use as a heat source for thermoelectric generators will become increasingly available in the coming years. The Atomic Energy Commission sponsored program on solidification of nuclear wastes is now entering the hot-bench scale test phase. During this phase approximately 5000 thermal watts of two year old MFP could be produced monthly. Two different types of hot calcination pilot plants are planned for installation at the Hanford National Laboratories in the 1964 to 1966 time period. Each of these plants should be able to produce 160,000 thermal watts of two year MFP and 16,000 thermal watts of ten year MFP on a monthly basis. A full scale plant for a 15,000 Mw(e) nuclear economy is estimated to produce four to five times as much MFP as either of the pilot plants. Costs will be dependent upon AEC policy in effect at the time the plant is operating."

"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."

"Results of the continuing stratospheric flight test evaluation program for the Del Model I Electrostatic Precipitator Sampler and the Del Electrical Discharge Altimeter are described and discussed. Only one of four balloon launches reached floating altitude. The altimeter obtained an altitude recording consistent with concurrent aneroid barocoder readings. The reported gross gamma concentration for the precipitator sampler was approximates 25 and 80% higher than those of the two simultaneous direct flow filter samples. The completion of the design and construction of two prototype units of the Del Electrical Discharge Altimeter and their laboratory evaluation are described. A preliminary design concept is presented for an operational high volume electrostatic precipitator sampler to operate with high collection efficiency at an ambient flowrate of 500 cfm throughout the altitude range 100,000 to 150,000 ft."

"The state-of-the-art of heat exchangers for gas-cooled reactor primary circuits is established by describing steam generators, primary heat exchangers, recuperators, and coolers of a number of gas-cooled nuclear projects, and by listing plant and exchanger main characteristics in three summery tables. Information is based in part on references indicated and in par+ on data from manufacturers. The availability of suitable heat exchangers is represented in the form of 35 Data Sheets submitted by manufacturers in response to our request. A list of manufacturers and their addresses is appended."

"An investigation was made into the various processes for the fixation of mixed fission products as solids in order to determine the extent they could be utilized as heat sources for thermoelectric generators. Generators of up to ten watts can be designed and built with state-of-art'' thermoelectric materials and mixed fission products soon to be available from the ldaho Falls calcination pilot plant. Mixed fission products from other processes and plants to be on stream'' in this decade will be capable of fueling practical generators into the kilowatt range using thermoelectric materials available in the same time period. A survey was made on current research and development efforts on waste fixation processes. Studies showed that a wide range of power densities (from 0.002 to 0.2 watts per cubic centimeter) will be available from calcined fission product wasted. An experimental program for the consolidation of low density, Idaho Chemical Processing Plant alumina type wastes is reviewed. Preliminary results indicated that densification factors of three to four are readily obtainable for such wastes."

"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."

In 1947 Bauer, and later independently Huntley (1948), pointed out that the helium content of iron meteorites as measured by Paneth and coworkers could be accounted for by the accumulation through cosmic-ray production rather then the decay of uranium and thorium. Bauer (1947) also predicted that the meteroitic helium should contain a significant proportion of He3. I was realized that by studying the effects of cosmic radiation on meteorites much could be learned about the history of meteorite and cosmic radiation. Chemical and instrumental techniques have been developed for the isolation, purification, and measurement of cosmic-ray-induced C14 in both stone and iron meteorites. The isolation of carbon from the silicate materials is done by fusion in an oxidizing flux in a vacuum system. From the iron meteorites the carbon is recovered by the decomposition of the metal in nitric acid in a closed system.

"The potential of closed-cycle gas turbines for producing a highly efficient nuclear power plant is discussed. Such turbines are being developed for three applications: the HTRE program (Heat Transfer Reactor Experiment) for nuclear aircraft propulsion, the MGCR program (Marine Gas Cooled Reactor) for nuclear marine propulsion, and the ML-1 (Mobile Low-Power Gas-Cooled Nuclear Power Plant) for nuclear electric power generation in an Army mobile power plant as part of the Army Gas-Cooled Reactor Systems Program (AGCRSP). Some characteristics of several non-nuclear gas turbines as well as gas turbine prime movers of 18 U.S. gas-cooled nuclear power plant projects were examined. Turbine and compressor performance, performance improvement, full-load and part load operation, maintenance, component life, and reliability are discussed. Consideration is given to factors affecting structural integrity of turbomachinery, such as choice of proper materials, vibrations, cooling, and construction features. The material reported is based on information obtained in part from the 155 references included and in part from the data requested from some 60 manufacturers."