Rivers can absorb certain amounts of contamination relying on different factors such as: river discharge, the primary conditions of the river, the river depth, discharge and the river viscosity of the offloaded wastes in the river. From parameters of water quality point of view, it is recom-mended to determine some parts of the river which are lower than the standard level in order to find out ...

A polypropylene hollow fiber membrane module is used for separating dissolved gases which contain dissolved oxygen from water. These dissolved gases can be used for underwater breathing. To be used for a human, the minimum amount of oxygen is essential. To increase separation of dissolved gases, much water and high surface area of hollow fibers are requested. For efficient separation system, pe...

A model of the concentrations of suspended solids (SS) in the aeration tanks and in the effluent from these during Aeration tank settling (ATS) operation is established. The model is based on simple SS mass balances, a model of the sludge settling and a simple model of how the SS concentration in the effluent from the aeration tanks depends on the actual concentrations in the tanks and the slud...

TODOR MISHONOV, STEFAN-LUDWIG DRECHSLER and EVGENI PENEV † Laboratorium voor Vaste-Stoffysica en Magnetisme, Katholieke Universiteit Leuven Celestijnenlaan 200 D, B-3001 Leuven, Belgium Department of Theoretical Physics, Faculty of Physics, Sofia University “St. Kliment Ohridski” 5 J. Bourchier Blvd., 1164 Sofia, Bulgaria Institut für Festkörperund Werkstofforshung Dresden, D-001171 Dresden, Ge...

Anaerobic bioreactors have been developed to remove perchlorate from water, but backwashing and operational interruptions can expose biofilms to oxygen. While it is well known that oxygen is a preferential electron acceptor to perchlorate for perchlorate-respiring bacteria, little is known about the effect of oxygen exposure or redox potentials on perchlorate reduction. Four different dissolved...

Enzymatic oxidation of 3,4-dihydroxyphenyl-L-alanine (L-DOPA) with laccase from Trametes versicolor was investigated. The highest enzyme activity at pH 5.4 and at 25 °C was found. The reaction kinetics and the effect of dissolved oxygen concentration on the reaction rate were evaluated. A mathematical model, comprised of double-substrate Michaelis-Menten kinetics and mass balances for L-DOPA an...

Robust statistical tools were applied on the water quality datasets with the aim of determining the most significance parameters and their contribution towards temporal water quality variation. Surface water samples were collected from four different sampling points during dry and wet seasons and analyzed for their physicochemical constituents. Discriminant analysis (DA) provided better results...