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Wpływ metod analiz na niepewność oznaczeń chlorowców w wodach powierzchniowych zlewni górnej Odry i w wodach kopalnianych do niej odprowadzanych

Dwornik M., Kmiecik E., Bebek M.

Przegląd Geologiczny

2015

Vol. 63, nr 10/1

705--709

In this paper the total uncertainty and its components (geochemical, sampling and analytical) were assessed with use of the empirical approach. For uncertainty estimation there were used results from analyses of normal and control (duplicate) samples, which were collected within monitoring of Upper Odra River Basin surface water and coalmine water inducted to it. Moreover, the influence of analyses method on the measurement uncertainty was examined. Results of ICP-MS, IC and titration methods were compared. The assessment of total uncertainty and its components was shown on the example of halogens (Cl −, Br − and I −) results delivered from normal and duplicate samples analyses.

Theoretical study on the kinetics and mechanism of reactions of halogen atoms with trifluoromethanol

Brudnik K., Jodkowski J. T., Ratajczak E.

Bulletin of the Polish Academy of Sciences. Chemistry

2003

Vol. 51, No. 2

77-91

Quantum mechanical ab initio calculations have been performed at various levels of theory to study kinetics of the reactions of fluorine, chlorine and bromine atoms with trifluoromethanol. Total energies were improved by using Gaussian-2 (G2) methodology. It is shown that the considered reactions proceed with formation of intermediate complexes. The mechanism of the reactions studied appears to be more complex and may consist of three elementary steps. The heights of the calculated energy barriers explain the differences of the reactivity of F, C1 and Br atoms towards CFsOH. The rate constants and their temperature dependence for the reactions CFsOH + X (fcx) and CFaO + HX (kfix) were calculated. The derived analytical expressions [chemical formulas] allow the description of the kinetics of the reactions under investigation. This is of considerable importance for the chemical modelling studies because of the lack of experimental measurements.