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This paper presents definitive values of the zero-pressure thermodynamic properties of the stable naturally occurring isotopes and the normal isotopic mixtures of the following monatomic gases: Hydrogen (H), helium (He), carbon (C), nitrogen (N), oxygen (O), fluorine (F), sulphur (S), chlorine (Cl), argon (A), bromine (Br), iodine (I), mercury (Hg). These values cover the range 100 to 5000 deg R at the intervals indicated by the numbers in parentheses: 100(5)130(10)240(20)500(50)1000(100)2000(200)5000. They have been computed by the methods of quantum statistical mechanics from present best values of the relevant (a) general physical constants, (b) isotopic weights and fractional abundances, (c) spectroscopic data. Computational accuracy well beyond present physical accuracy has been maintained for practical reasons, final results being given to seven significant figures. Present physical accuracy is indicated by charts of estimated uncertainties. For some of the monatomic gases here considered, accurate values of their zero-pressure thermodynamic properties hitherto have been unavailable; for others the data presented are the first based upon recent spectroscopic and other input data to be made available at temperatures sufficiently close for convenient practical application.

In this report are presented tables of the principal thermodynamic properties of carbon monoxide and of nitrogen along the zero-pressure isobar in the range 100 to 5000 deg R at the intervals indicated by the numbers in parentheses as follows: 100[5]130[10]240[20]500[50]1000[100]2000[200]5000. The data have been computed by the method of quantum statistical mechanics in the University of Pennsylvania Thermodynamics Research Laboratory under Project G-3. Computational accuracy well beyond present physical accuracy has been maintained for practical reasons. It is believed that the tables given herein should supersede all previous ones. The calculated values are in satisfactory agreement with those obtained from calorimetric and acoustic velocity measurements.

Cultures containing mixed flora from raw milk were heated at 62.8 C for 15, 20, 25, and 30 min. Dilutions were filtered through membrane filters, and the filters were incubated on Trypticase soy broth (TSB) and on TSB plus NaCl (TSBS). The TSB count indicated the total population which survived heating and included injured and uninjured cells. The colonies on TSBS indicated the uninjured cells and were marked by perforating the membrane near the colony. This membrane was then transferred to fresh TSB and incubated further. The injured organisms recovered and formed colonies which could be distinguished from previous colonies of uninjured organisms. Transfer counts on TSB were not substantially different from the initial TSB counts at 15, 20, 25, and 30 min of heating.

Several investigators have attempted to analyze the performance of the ejector on a one-dimensional basis. Some doubt exists whether such analyses can lead to a rational ejector design because of the questionable validity of certain necessary assumptions. Recently, consideration has been given to the two-dimensional aspects of the problem, and while a rational design has not yet been evolved, the results attained seem to point in the right direction. The theory of turbulent mixing in jets, developed by Tollmien is used as the basis of the study reported in this paper. Tollmien’s analysis of the mixing zone produced by a homogeneous air stream issuing into still air of the same pressure and density is reviewed. The authors then extend the theory to allow for the possibility that the driving and driven fluids may have widely different densities.

The gas-current method of measuring latent heat appears to possess important advantages over other calorimetric methods. Preliminary results have been derived from a co-operative investigation carried out by the American Society of Heating and Ventilating Engineers and the Towne Scientific School, University of Pennsylvania, in which sufficiently reliable values of the interaction constant for air-and-water-vapor mixtures have been determined to permit an adequate thermodynamic analysis of the gas-current method. The present paper is devoted to the development of this analysis and its application to the reduction of certain experimental data recently obtained by one of the authors. The apparatus and method of conducting the experiments are also described.