The following report focuses on the study of electrostatic classification of submicron aerosols, with emphasis on particles below 0.1 micron. During the period this work was concerned with detailed studies of the ARF charger, the Whitby ionizer used as a charger or neutralizer, and the high-volume classifier.

Introduction: "This study is concerned with the classification of submicron aerosols by electrostatic means. The controlled charging of the particles without undue aerosol losses is of principal interest. We are investigating means of eliminating the interference due to the deposition of small and large particles in the same area. The sampler is to be developed to classify atmospheric dust particles at a rate approaching 1 cfm. During the period covered by this report, work was concerned with the charger and with bringing the high-volume classifier into routing operation. Further tests were made on the classification of atmospheric dust."

Introduction: "This project is a study of eletrostatic classification of submicron aerosols with emphasis on particles below 0.1[mu]. Previous work has shown that classification of particles between 0.1 to 1.0[mu] is feasible by this process. Further improvements along this line include the elimination of interference from initial aerosol charge and increase in sampling rate. The effect of heavy deposits on collection have to be established. More information is desired on the charging regime below 0.1[mu]. Also the overlap of the smallest particles with the larger ones has to be eliminated. It is also of interest to study the possibility of measuring the current due to the precipitating particles. This would make it possible to automate the device. During this period project work was initiated again. There was some delay in finalizing the contract and the laboratory work was not started until early in March."

Introduction: "This project is a study of electrostatic classification of submicron aerosols, with emphasis on particles smaller than 0.1 micron. The overlap of the smallest particles with the larger ones is of principal concern. Also, a faster sampling rate is desired, i.e., heavier deposits in a shorter time are necessary. During the period covered by this report, work was concerned with studies of charging by corona and diffusion, neutralization of initial charge, and classification of various types if aerosols."

Introduction: "One of the major objectives of this study is to develop a routine charger that has no aerosol losses. Also, the interference due to deposition of small and large particles in the same area must be overcome. During this period efforts were concentrated on the former problem, which is the key to practical application of this device."

From abstract: "This document constitutes ARF Report No. 1207-6, and is a quarterly report on research on the preparation of high specific activity radioisotopes".

A report about obtaining low energy neutron capture gamma-ray spectra of a suitable quality for inclusion in the Atlas. It analyzes several low energy spectra obtained from many sources.

A report which intends to make a compilation of neutron capture gamma ray spectra of naturally occurring elements, covering both the low and the high energy spectral region, using NaI(TI) scintillation detectors.

A report which describes the how the low energy neutron capture gamma ray spectra has been obtained for inclusion in the atlas along with many ores. In addition to gaining this spectra, tests were conducted with the 5'' by 4'' NaI(TI) crystal in the present detector system.

A report which determines the effect of polarizing magnetic field intensities on the fraction of nuclear resonant absorption using a simple electromagnet.

A report about the absorption of gamma rays. Absorption measurements were made using pressures up to 40,000 psi, but no measurable changes were found over this range. Experiments were carried out to determine whether there was any change in the fraction of recoil free emissions of gamma rays.

A report about 3 tasks which are undergone in this project. These tasks pertain to preparing computer codes for calculations of wave transmission in layered composites of materials, the performance of gas shock impingement experiments, and analyzing previously obtained experimental data using a liquid driven shock tube.

Report discussing the progress made on various research programs at the Armour Research Foundation during the period from May to June 1962.

A report that aims to resolve three problem areas. These solutions involve extending the incremental method to apply to the solution of cylinders with a rigid base and a hemispherical head, investigating shield-structure interaction, and the determination of the dynamic response of vessels with various end conditions.

A report about analyzing the responses of containment vessels, the effect of openings on the strength of containment vessels, bulging experiments on pressurized cylinders of finite length, and the development of the containment handbook.

A report about a project which aims to resolve three problem areas. The first problem pertains to a solution for a rigid-strain hardening material obeying the Mises yield condition, the second area relates to preparing the FORTRAN program for a solution of the simplified shield structure model, and the third area relates to computer programs for the response of spheres and infinite cylinders have been rewritten in FORTRAN.

A report intending to determine optimum beta-excited x-ray source designs which will demonstrate practical uses of the isotopic sources for medical and dental radiography, inspection of missile and airplane structures, and other nondestructive testing problems.

Abstract: "The purpose of this investigation is to determine the extent to which zirconium exhibits delayed failure (static fatigue) as caused by a combination of absorbed hydrogen and applied stress. Both notched and unnotched specimens of unalloyed zirconium and Zircaloy-2 are being initially hydrogenated to 200 ppm by means of a modified Sieverts apparatus, and delayed failure studies are proceeding at room-temperature. Thus far only preliminary data on unnotched, unalloyed zirconium are available; at the 200 ppm hydrogen level, this material appears to be relatively insensitive to delayed failure at room-temperature."

From introduction: "A detector system with the advantages of a liquid counter, but without the severe requirements on sample preparations, has been devised and is the basis of the present experimental investigation."

The following report is the first semi-annual report of a literature survey designed to investigate the uses and technology of radioisotopes in the countries of the world from 1955 to the present. This survey includes two phases: 1) involves the direct comparison of radioisotopic work in all fields in various countries as demonstrated at international conferences. 2) involves a more detailed examination and evaluation of the individual fields of interest selected previously (Phase II is also expected to comprise the bulk of the remainder of this investigation).

Quarterly report describing the progress and development of improved zirconium alloys for service in superheated water and steam. This report covers the period between October 1 to December 31, 1961 and was conducted by the United States and the European Atomic Energy Community (EURATOM).

Report discussing a study of various neutron image detector systems and their characteristics, and opal glass diffusers in an optical image synthesis apparatus. A five inch diameter neutron beam exposure facility is also discussed.

Annual technical report describing the progress and development of improved zirconium alloys for service in superheated water and steam. This report covers the period between February 1, 1961 to February 28, 1962 and was conducted by the United States and the European Atomic Energy Community (EURATOM).

Abstract: "The purpose of this investigation is to determine the extent to which zirconium and zirconium alloys exhibit delayed failure (static fatigue) as caused by a combination of absorbed hydrogen and applied stress. Both notched and unnotched specimens of unalloyed zirconium and Zircaloy-2 have been hydrogenated to 200 ppm by means of a modified Sieverts apparatus; specimens were evaluated at room temperature. Thus far, no time-dependent fracture has been observed which can be attributed to the delayed failure phenomenon; it appears that these materials are relatively insensitive to static fatigue. The effects of grain size, temperature, cold deformation, and superheated water and steam corrosion on susceptibility to delayed failure are being determined."