The analysis of Berezin and Kiselev’s concept assuming linear association of molecules in a localised adsorption monolayer on the homogeneous surface of a solid adsorbent was carried out. An inconsistency due to the lack of consideration of equilibrium concentration of free adsorption sites in the formulation of the expression for the association constant has been pointed out. It was shown that the correct form of this function leads to the final adsorption equation being identical to the specific case of the Fowler-Guggenheim equation. The obtained result has been generalised to cases of branched adsorbateadsorbate associations. A new adsorption equation limiting the association to at most the dimers has been introduced. Critical conditions for the two-dimensional condensation of the adsorption layer were determined. By applying the formalism of canonical ensemble, full equivalence of the phenomenological and statistical methods was demonstrated in the description of the intermolecular interactions in the localised adsorption monolayer.
This paper characterises the concept of monolayer mobile gas adsorption on a homogeneous surface of a solid. The theoretical basis of the phenomenological variant of the description of adsorption equilibrium in the system in question are discussed. The essential features of the solutions to date are discussed, and the effect of the free surface of adsorbent on the form of the final adsorption equation is stressed.
An alternative concept of the free surface based on the modified two-dimensional analogue of Reiss, Frisch and Lebowitz equations is also presented. The obtained adsorption equation was tested for critical parameters of two-dimensional condensation of the adsorption layer, and then used to describe the experimental data available in literature. The verification carried out confirmed the correctness and usefulness of the proposed concept.
This paper presents an analysis of thermal and oxygen conditions of the Charzykowskie Lake in the years 2014-2016 in the period from May to August. The measurements were carried out once a month, at points representing three different basins in the lake, and the temperatures and oxygen content dissolved in the water were recorded every 1m from the surface to the bottom at the deepest point of each basin. The changes in temperatures and content of dissolved oxygen were analysed in each of the representative measurement points for particular parts of the lake. It has been shown that the deficit of oxygen dissolved in the bottom layers of the water starts occurring by the beginning of the summer stagnation period, whereas at its peak (August) the anaerobic zone includes hypolimnion and part of the metalimnion. The hypothesis that the thickness of the thermal layers varies within the lake basin was confirmed. It was also shown that the oxygen content curve at representative points, in all years of research, evolves to the form of a clinograde at the peak of summer stagnation, where the concentration of dissolved oxygen decreases with the depth.
The subsequent stages of the process of formulation of the equation for gas adsorption on a homogenous surface of a solid adsorbent were presented based on the general expression for the canonical ensemble of the mobile single-component adsorption monolayer. The method of formulating the configuration integral of the proposed model was discussed in detail where the role both of the attraction and repulsion between adsorbed molecules was emphasised. The expression for the probability of finding a molecule in a specified point on a surface of an adsorbent was modified by determining its magnitude by the adsorbent concentration. The expression for the so-called effective surface of the adsorbent was obtained by adapting a two-dimensional analogue equation of state hard spheres – Van der Waals equation (2D-vdW) and Reis-Frisch-Lebowitz equation accordingly (2D-RFL). As a result, two new adsorption equations were formulated which differ in detail concerning the adsorbate-adsorbate repulsion. On each of these equations theoretical analysis was performed in terms of two-dimensional phase transformation. In both cases it was proved that the proposed solution allows for the presence of two-phase transformations of the first type which is the gas-liquid condensation and solidification liquid-solid. The verification of the given approach was supplemented by the description of the experimental data given in reference literature and by obtaining a very good correlation between the theory and experiment.
Continuing the discussion on the description of adsorbate-adsorbate association on homogeneous surfaces of solids, an attempt was made to formulate an analytical form of adsorption equation for a multilayer adsorption phase. The validity of Berezin’s and Kiselev’s assumptions concerning the independence of adsorption in further layers from the model of the phenomenon in the first of them was discussed. The fundamental validity of this assumption has been demonstrated, simultaneously ridding it of its arbitrary character. The main aim of the study was to demonstrate the possibility of formulating a description assuming molecule association in the entire adsorption phase (and not only in the first layer). Theoretical considerations are confined to the case of dimerisation in the concentration range thus warranting the approximation characteristic of the Berezin and Kiselev model. The obtained final adsorption equation exhibits physically acceptable boundary properties; with adequate assumptions it amounts to the Brunauer, Emmett and Teller equation, the equation formulated earlier by one of the authors of this paper or the Langmuir equation.
This article is related thematically to two of our earlier publications, which demonstrated full equivalence of statistical and phenomenological methods in the description of physical gas adsorption on the surface of a solid body, and the fundamental possibility of analytical solution of adsorbate-adsorbate association problems in the entire multi-layer adsorption phase. The quasi-chemical scheme of secondary interactions leading to the formation of horizontal multimolecular adsorption complexes has been elaborated. A new adsorption equation was formulated taking into account the dimerisation of adsorbed molecules in the whole adsorption phase, as well as the influence of topography of the binding sites of adsorbent surfaces on the form of this solution.
This work is a preliminary pilot research aiming at defining the role of the Piechcin Diving Centre in the development of specialised tourism. Particular attention was paid to the various elements defining the quality of the services offered. The key aspects and reasons for which respondents visit the centre were also determined. Both the customer’s expectations of the organiser of this form of recreation were analysed, and research was made to help understand whether the time the customers spends at the centre facilitates a positive decision regarding the participation in diving trips in larger bodies of water, with particular consideration of the Baltic Sea. Different forms of cooperation between the centre and regional authorities in terms of promoting the region were also reviewed.