W pracy przedstawiono wyniki pomiarów jonów metali ciężkich w glebach poboczy dróg znajdujących się na terenach chronionych oraz ich analizę statystyczną.
EN
The paper presents results of the measurements and the statistical analysis of the concentrations of selected heavy metals ions in the wayside soil of the nature reserve area.
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W związku z trudnościami w opracowaniu strukturalnego opisu, który wyjaśniłby dynamiczne zachowanie czystej wody, w konsekwencji muszą pojawiać się również problemy w opisaniu jej struktury w obecności kationów i anionów. Stopień uporządkowania struktury wody wokół poszczególnych jonów badano wielokrotnie i to różnymi metodami. Jednakże, jak to zostanie przedstawione w dalszej części niniejszego artykułu, wyniki owych prowadzonych niezależnie od siebie badań nie zawsze są ze sobą zgodne. \między innymi może to być wynikiem braku jednoznacznego opisu strukturalnego wody.
EN
The aim of this work was to present and compare various methods of the determination of the influence of ions on the water structure. The reasons of the discrepancies between the results obtained by different workers and methods are explained. We have presented the model of the hydrated ion proposed by Marcus, who used this model to describe the hydration process and its conceptual stages. In the model of 'fluctuating icebergs' proposed by Frank and Evans, solutes were considered to order water molecules around themselves. Ordering of water ('iceberg formation') was believed to occur by the formation of interconnected networks of hydrogen bonds. Solutes which imposed order (i.e. promoted iceberg formation) were considered to be structure makers. Similarly, solutes which decreased order were said to be structure breakers. The influence of ions on the water structure can be determined by means of: 1) comparison of the interaction energies among water molecules around the ion with those in pure water; 2) the viscosity B-coefficients of the Dole-Jones equation, the average number of hydrogen bonds in which a water molecule participates (DGHB), a residual entropy (Sstr) and heat capacity of hydration (Cpstr) due to the change in the structure of the water ; 3) analyzing the laser-Raman spectra of water in the region of OH stretching vibration. We have compared the results of investigations of structure-making and structure-breaking properties of the ions. The observed discrepancies between the results obtained by different workers and methods can be caused by: 1) a different interpretation of the influence of the hydrated ion on the water structure, 2) experimental results depend on the phase of water: bulk or interfacial region, in which the measurements were performed (different properties and structure of both water phases, 3) different definitions of the hydration sphere implying a confusion in the concept of the ion hydration structure, 4) different sensitivity and accuracy of the measurement methods used, 5) different models, assumptions and simplifications, 6) the different orientation of water dipoles around cations and anions has not been taken into account in models and calculations.
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