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ZnO added to the system Portland cement -water changes the kinetics of the hydration process substantially. Amorphous zinc hydroxide is formed and inhibits the reaction of tricalcium silicate with water, resulting in an induction period prolongation. This effect depends on the amount of ZnO added to the hydrated paste. The transformation of zinc hydroxide into calcium hydrozincate provokes the further hydration.

Depending on the calcium:phosphorus molar ratio of the initial precipitates determined by precipitation conditions (calcium:phosphorus molar ratio of reactants and pH of reaction environment), after sintering at 1250°C, monophase, biphase, or triphase ceramics consisting of hydroxyapatite, β‐tricalcium phosphate, α‐tricalcium phosphate, and calcium oxide were obtained. The phase composition and properties—i.e., density, shrinkage, hardness, bending strength, and roughness—of the fractured surfaces of the isostatically re‐pressed sinters were determined.

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The paper features a description of a sensitive adsorptive stripping voltammetric protocol for the palladium(II) determination in the presence of dimethylglyoxime (DMG) at an amalgam film electrode (Hg(Ag)FE) of prolonged analytical applicability. The procedure is based on the adsorptive preconcentration of the Pd(II)-dimethylglyoxime complex onto the (Hg(Ag)FE) at À 0.45 V, followed by a negatively going square-wave voltammetric scan. Factors affecting the stripping performance, such as the composition of the supporting electrolyte, including different ligands, DMG concentration, pH, potential and time of preconcentration, and SW frequency have been investigated and optimized. The optimized procedure yields favorable and highly stable stripping responses with good precision (RSD ¼ 3% for a Pd concentration of 2 mg/L), low detection limit (0.15 mg/L Pd(II)), and good linearity (from 1.0 mg/L up to 50 mg/L, R 2 ¼ 0.998) with a deposition time of 60 s. Possible interferences from coexisting ions and surface active substances were studied.