The reactions of potassium ethyl xanthate (KEtX) and its oxidation product diethyl dixanthogen (EtX)₂ were studied in neutral and mildly alkaline aqueous solution. Dissolved oxygen-was shown to be ineffective in oxidizing KEtX in homogeneous systems (solution), but (EtX)₂ was produced electrochemically at a platinum electrode by application of a small anodic overpotential. A slow hydrolysis reaction was proposed for the alkaline decomposition of aqueous ethyl xanthate in which carbon disulfide and ethyl alcohol were the decomposition products. The first order rate constant k₁ = 7.6 ± 1.0 x 10⁻⁴ hr⁻¹ (22°C) was independent of pH in the region pH 7 to 11. Low concentrations of (EtX)₂ (10⁻⁵ to 10⁻⁷ moles liter⁻¹) were determined by a new method based on extraction of the aqueous (EtX)₂ by hexane followed by ultraviolet spectrophotometric determination of the (EtX)₂ in the hexane extract. A sensitive technique for measuring saturation of (EtX)₂ in water using light scattering photometry; was also developed. The solubility of (EtX)₂ in water was found to be 1.27 x 10⁻⁵ moles/liter at 22°C from pH 2 to 8.5. At pH > 8.5, aqueous (EtX)₂ was shown to react with hydroxyl ion by a bimolecular displacement (SN[subscript omitted]2) mechanism which resulted in the formation of one mole of ethyl xanthate and one mole of an intermediate ethyl xanthate sulfenic acid. Decomposition of the intermediate compound resulted in carbon disulfide and other reaction products. The second order rate constant (k₂ = 13.5±0.5 liter mole⁻¹min⁻¹ at 22°C) was determined. Rest potential measurements using a platinum electrode in potassium ethyl xanthate-diethyl dixanthogen solutions showed that the Nernst equation for a one electron reaction was obeyed over a wide range of both KEtX and (EtX)₂ concentrations. Dissolved oxygen was found to generate mixed potentials to which no overall reaction could be assigned. It is expected that the rapid oxidation of ethyl xanthate to diethyl dixanthogen observed in mineral systems proceeds by a catalytic oxidation or electrochemical reaction at or near the mineral surface. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

Two experiments are described. One is the successful observation of the resonant deflection of a beam of neutral potassium atoms at a frequency of 7.2 Mhz, in agreement with the predictions of the theory of the Transverse Stern-Gerlach (TGS) experiment. The other is a proposal for a charged particle Stern-Gerlach experiment, which is based on an extension of the TSG experiment to time independent, inhomogeneous magnetic fields having the form [formula omitted] If the field B₁(r) is well chosen, the charged particle trajectories are confined in a stable beam by the resulting Lorentz forces for motion generally along the z axis. This is, in fact, the principle of strong focusing which is now widely used in accelerator design. But in such a system it is also possible to satisfy the criterion for a TSG experiment, since in a frame of reference moving with a particle in the z direction, the field B₁(r) is rotating in time. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

Potassium i.s one of the major constituents of the human body but its role in metabolism is not clearly defined. One reason for this is the predominant intracellular distribution of the ion and the attendant difficulties in the detection of deficiency states. Serum potassium levels are of little value as over 95% of the potassium in the body is intracellular. Balance studies and the analysis of biopsy material have been used. However, they are so time consuming that they are only of use in establishing the diagnosis retrospectively and give very little indication of the severity of the deficit. Exchangeable potassium measurements do give an indication of the severity of the deficit. However, they involve the administration of an isotope which is not always available because of its short half-life. The development of the whole body counter has overcome most of these problems.

Indiana University-Purdue University Indianapolis (IUPUI) / Excessive sodium retention is thought to be the main culprit for hypertension. The modern American diet provides an excess of sodium and not sufficient amount of sodium. In this research, we examined the relations among urinary sodium and potassium excretion, and plasma levels of aldosterone, a mineralocorticoid hormone that has been linked to incidence hypertension, in a cohort of healthy children and young adults. We found that higher plasma aldosterone level was associated with lower sodium excretion in the urine, in blacks and whites, suggesting that aldosterone plays a critical role in retaining the sodium from dietary sources. The study highlights the importance of dietary sodium restriction.

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