Jarosite, a potassium (sodium) iron sulphate hydrated mineral, has recently been identified on the martian surface by the Opportunity rover. Using recent thermochemical data [Drouet and Navrotsky, 2003, Geochim. Cosmochim. Acta 67, 2063–2076; Forray et al., 2005, Geochim. Cosmochim. Acta, in press], we calculate the equilibrium decomposition curve of jarosite and show that it is thermodynamical...

producers in the Matanuska Valley today, it was considered appropriate to expand upon the previous work using current production practices. Potassium was supplied as KCl and K2SO4 to explore the need for additional S under local potato production conditions and to determine the effects of the chloride (Cl) and sulfate (SO4) anions on production and quality of potato tubers. In addition, Mg and ...

MALNIC, GERHARD, RUTH M. KLOSE, AND GERHARD GIEBISCH. Micropuncture study of renal potassium excretion in the rat: Am. J. Physiol. 206(4): 674-686. I g64.-Samples of proximal and distal tubular fluid were collected from rats maintained on a control, a low-K, or a high-K, low-Na diet. All animals received inulin-C 14. Plasma (P) and tubular fluid (TF) were analyzed for Na and K by dual-channel m...

Oxidation–reduction titrations and potentiometric methods provide a convenient experimental means to quantitatively determine compositions of unknown mixtures containing oxidizable/reducible species. Over the past decade, numerous titration methods have appeared in this Journal (1–6) and in standard laboratory manuals (7–10) involving common titrants such as potassium dichromate, iodine, potass...

Inhibition of purified AMP-deaminase from chicken breast muscle by phosphate esters and inorganic phosphate has been investigated. When tested at a concentration of 3 mM, in the presence of 0.15 M potassium chloride, the order of effectiveness as inhibitors of deaminase activity was: 2,3diphosphoglyceric acid, 3-phosphoglyceric acid, 2-phosphoglyceric acid, 2-phosphoenolpyruvate, fructose 1,6di...

In vitro studies of the secretory behavior of the parietovisceral ganglion in Aplysia californica were performed. The aim of these studies was to investigate the release of polypeptides in response to depolarizing stimuli, and, in particular, to determine if a specific polypeptide known to induce egg laying in the intact animal is secreted into the bathing medium. During continuous perfusion of...

In vitro studies of the secretory behavior of the parietovisceral ganglion in Aplysia californica were performed. The aim of these studies was to investigate the release of polypeptides in response to depolarizing stimuli, and, in particular, to determine if a specific polypeptide known to induce egg laying in the intact animal is secreted into the bathing medium. During continuous perfusion of...

Background and aim: The frequency of sensitization to contact allergens varies in different countries because of both genetic and, more importantly, allergen exposure variations. The objective is to determine the frequency of sensitization to contact allergens in Iranian patients with dermatitis.Materials and methods: Four hundreds and one patients with a clinical diagn...

This study was done to evaluate the effect of different planting arrangements (square, lozenge and rectangular) and various concentrations of potassium sulfate (K2SO4) fertilizer (0, 100, 200 and 300 kg/ha) on yield and essential oils quantitative of Calendula officinalis L., a medicinal and ornamental plant. The experiment was done as a factorial in randomized completely blocks design (R.C.B.D...