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Total charge transfer cross sections have been measured for the reactions of 0.6 to 3.0 keV O+(4S) and O+(2D) ions with Ar, H2, N2, O2, CO, NO, and CO2. Time-of-flight techniques have been used to measure the fast neutral O products from charge transfer reactions in which reactant O+ ion beams have been produced by controlled electron impact ionization of oxygen. Reactions have been examined as a function of the electron energy used to produce the reactant ions and reaction cross sections determined for ground O+(4S) and excited O+(2D) state ions. The cross sections for charge transfer reactions involving the excited O+(2D) ions are significantly larger than the corresponding reactions of ground state ions in each of the above systems with the exception of CO2 where the revserse situation occurs due to small energy defects and favorable vibrational overlaps for reactions of O+(4S) ions.

Mass spectra obtained using fast atom bombardment provided qualitative information about coagulation's effectiveness under various treatment conditions. Removal of natural aquatic dissolved organic matter (DOM) by conventional coagulation using ferric chloride was investigated. Reverse osmosis was used to isolate DOM from the Suwannee River in southern Georgia and from Lake Allatoona in northwestern Georgia. The two most significant differences between the source waters are pH and organic carbon concentration. Extensive jar‐testing identified regions of removal based on initial concentration of DOM, coagulant dosage, and pH conditions. Fast atom bombardment mass spectrometry was used to characterize the molecular‐weight distributions of DOM before and after coagulation. Trends in the shape of the mass spectra correlated well with data for DOM removal and suggested that the mechanism for DOM removal varies with the pH and coagulant dosage. At higher pH conditions and lower coagulant dosages, masses up to 1,000 daltons (D) were detected in the mass spectra after coagulation. At lower pH conditions and higher coagulant dosages, no masses above 750 D appeared in the mass spectra.

ALTHOUGH bacterial invasion of the developing ovum is known to occur (Haines, 1939), it is fairly clear that the microbial decomposition of eggs encountered in commercial handling is due, in the main, to the invasion of the egg by spoilage-producing micro-organisms after laying. This in turn depends on (a) the inherent porosity of the shell, and (b) the treatment the egg receives, e.g. washing. The present work is an attempt to gain information on these two factors.THE POROSITY OF THE SHELLThe porosity of the shell may be studied (1) by histological methods and (2) by measuring the rate of movement of liquids or gases through the shell under a given pressure gradient. Difficulties have been met in applying both these techniques. The first has given a useful picture not, however, amenable to quantitative interpretation, whilst the second has shown that porosity is a relative term, varying at different points on the shell and in successive eggs from the same hen.(1) Histology P1. IX, fig. 1 is a transverse section ( x 120), normal to the surface, of the eggshell. Four layers can be distinguished. These are: first, the cuticle, composed mainly of fibres of mucin (Moran & Hale, 1936); secondly, the spongy layer consisting of crystals of calcite more or less normal to the cuticle; thirdly, the mammillary layer, also consisting of crystals of calcite, which however do not appear to be definitely orientated; and fourthly, the inner shell membrane.P1. IX, fig. 2 shows a section of a shell, again normal to the surface ( x 100), in which pores or V-shaped openings can be seen stretching from the outside (cuticle not present) to the mammillary layer. It is evident that these pores do not pass right through the shell as has been claimed by Marshall & Cruickshank (1938). The diameter of one of these openings was 13 ,u at the top, 6 , at the bottom. P1. IX, fig. 3 is a section ( x 75), cut parallel with the surface of the shell, in the third or mammillary layer, near the inner shell membrane. The extreme irregularity of the structure is shown, with spaces of various sizes between the calcite crystals which possibly form canals or pores leading to the interior of the egg.