Mechanically polished zirconium electrodes were potentiodynamically polarized in phosphate buffer solutions of various pH values and in 0.5 lvl NaOH. The results show that the shape of the I-E curves is independent of the solution pH. At relatively low scan rates, oxygen gas evolution was observed. The oxide film thickness was calculated from the values of the charge consumed in the anodic process assuming 100% current efficiency for oxide formation below oxygen evolution (lower values for the current efficiency are assumed for potentials above oxygen evolution). Capacitance measurements, together with the calculated oxide thickness, were used to estimate values for the dielectric constant of the oxide. Two different values of the dielectric constant were obtained for the oxides formed in the range of potential below and above oxygen evolution. Also, higher dielectric constant values were obtained with increasing solution pH. Anion incorporation was assumed to increase the conductivity of the oxide films and, hence, decrease the dielectric constant. A two-layer structure is proposed for the anodically formed oxide on zirconium in aqueous solutions; an anion-free layer near the metal and an outer layer containing the incorporated anions.

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capozide was administered in a dose of 1.012 mg/200g rat body weight once a day for 4 weeks to normal and diabetic rats. It had no effects on serum potassium urea or creatinine. No increase in lipid concentration to negate its beneficial hypotensive effect, was noted. Form oral glucose tolerance test, it was calculated that the drug improved glucose tolerance concomitant with the increased beta cell function and peripheral insulin response.
The interaction between the two components of capozide, captopril an angiotensin converting enzyme inhibitor, and hydrochlorothiazide, a diuretic, is discussed in regards to carbohydrate and lipid homeostasis.

The electron transfer kinetics of the Fe3+/Fe2+ redox couple on the oxide covered Ti electrodes were investigated as a function of the film thickness, film stabilization, and concentration of the redox species. The oxides were formed potentiodynamically in acidic solution of pH=3 (Na2SO4+H2SO4) at a scan rate of 1 mV s−1. The cathodic and anodic Tafel lines were also measured at the same scan rate.

The logarithm of the exchange current density i0 shows an exponential decrease with the oxide film thickness. Direct tunnelling may explain the kinetics of the reaction across thin Ti02 (oxide formed at the potential region before the O2-evolution). Values of the cathodic and anodic transfer coefficients are tabulated. It was found that, the stabilization of the oxide could possibly increase its conductivity. The electron transfer reaction showed a first order dependence on the redox species concentration, independent of the conditions of oxide film formation.

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