Abstract: This technical report describes the changes incurred in the PM-2A by the planned insertion of PM-2A Core II and the replacement of the startup and check sources. PM-2A Core II components were fabricated to specifications very nearly identical to those of PM-2A Core I. The essential difference in the cores is the boron loading which permits PM-2A Core II to meet a "one-stuck rod criteria" at beginning of life. This core has been subjected to a zero power experiment and loading procedures have been developed at the Alco Critical Facility. The nuclear and thermal and hydraulic characteristics are essentially identical to those of Core I and the replacement of the startup and check sources represent no increase in the potential for or magnitude of a hazardous situation.

From abstract: "The electronic spectra arising from the excitations of pi-electrons in homo-nuclear conjugated bond systems are calculated for 37 aromatic hydrocarbons. The theoretical approach used takes into account overlap effects between different a atoms, correlation between different electrons, variations in internuclear distances, and the influence of non-conjugated neighbors, hydrogen and carbon. Four types of approximations are carried trough for the molecules in order to obtain an estimate of the inadequacies of the theory. From the calculated transition energies and oscillator strengths, theoretical spectra are synthesized and compared with observed spectra. In order to help the interpretation, a decomposition of the transition dipoles into atomic contributions is introduced. The spectra of alternant molecules are succesfully predicted, but the limits of the underlying assumptions appear to be exceeded in the applications to non-alternant systems. The calculations are markedly successful for the peri-condensed systems, which had presented an obstacle to previous treatments. It is found that the calculated spectra are fairly sensitive to small variations in interatomic distances. calculations with exact atomic positions, where available, give considerably better agreement with experimental spectra. The calculations lead to an understanding of the general spectral pattern found in all aromatic hydrocarbons. On this basis the …

Report discussing wavelengths and estimated intensities in electrodeless lamp and spark sources presented for 15121 lines of ThI, ThII, ThIII, and ThIV in the spectral range from 2000 to 11550 A. Also contains tables of previously published interferometric values.

Report discussing how solids subjected to non-uniform temperature change develop internal stresses determined by, (1) the temperature distribution within the solid, and (2) certain physical constants of the material. For two varieties of heating, the equations determining stress have been put in convenient form for practical use, and tables of certain temperature functions show how to determine stresses in a slab, in a cylinder, or in a sphere subjected to either of two modes of heating. The temperature-distribution tables independently provide a useful means for the ready estimation of temperature gradients.

Reports discussing bands of common gases that have been tabulated and remeasured wherever necessary from 2 to 16 microns to obtain an accuracy of about 0.03 cm-1 throughout the region and to provide good calibrating points at frequent intervals. Some 600 rotation-vibration lines are illustrated in 20 spectrograms and wavenumbers are listed in companion tables with considerable intercomparison with worthy data obtained in other laboratories. The absorption bands were remeasured or calibrated by using either a precisely graduated grating circle or standard atomic lines with the fringe system formed by a Fabry-Perot interferometer. Characteristic features of the individual bands are discussed briefly and references to other publications are given. The substances used for calibration include H2O, CO2, CO, HCl, HBr, NH3, C2H2, CH4, N2O, and polystyrene film.