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A complex investigation was performed for a polluted area using both experi-mental and computer modelling methods. Among the experimental methods the adsorption and desorption isotherms were measured to estimate the concentration dependent equilibrium in the soil-groundwater system. A new calculation method was worked out for determining the transport para-meters from results of laboratory tests. Heavy metal solution was leached through a soil column continuously. The effluent fluidum was collected, and the heavy metal concentration of the collected fractions was measured by atomic absorption spectrophotometer. As the result of the analytic process breakthrough curves were measured in laboratory scale. Due to the applied initial and boundary conditions the transport equation can be solved analytically. Using the Ogata and Banks (1961) solution of the transport equation a new curve fitting method was introduced. After several transformations of the equation a theoretical function was fitted to the measured concentration vs. time and to the concentration vs. effluent volume data. The parameters of the fitted curve could be used as the dispersion and retardation parameters of a transport model.  The water chemistry of the system controls the rate of adsorption and desorption of metals to and from sediment. Adsorption removes the metal from the water column and stores the metal in the substrate. Desorption returns the metal to the water column, where recirculation and bioassimilation may occur. Metals are probably desorbed from the soil if the salt concentration of the water increases, and in case of some metals decreases with the redox potential and with pH.  Parallel to determining the basic transport parameters of the system using the column study, the maximal equilibrium concentration of chromium-containing compounds with different oxidation states were calculated with the MINTEQ model with two variable functions (pH and redox potential). As a result of the calculations a non-liner relation was established, as at specific points the maximal equilibrium concentration of chromium increases with a high gradient. This means that there are combinations of pH and redox potential values in the case of which chromium has a high solubility. It is advisable to avoid these points in the pH-E h field if we want to stabilize the contaminant. This state is to be reached when the goal is the mobilization of the pollutant to make the soil cleaning process possible. With the introduced calculation method areas on the pH-redox potential field (at high pH and E h values) are found in which the concentration of pollutants may reach a critical value. The introduced calculation method is quick and gives results accurate enough for a pilot test.

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evaluated from the equation derived by Townsend and Tou for an adiabatic process [ 23 ] or by curve fitting method in CISP [ 19 ]. The kinetic parameters of 20 mass% MEKPO were measured by the latter one. Its values of ln( k o ), E a , n , Q parameters

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Yb 3+ ions. The luminescence decay curve of the undoped host crystal MgAl 2 Si 2 O 8 : Mn 4+ , Yb 3+ phosphor is are shown in Fig. 8 . Decay time can be calculated by a curve fitting method based on the following single exponential

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