this paper presents an inventory model for deteriorating items in which shortages are allowed. it is assumed that the production rate is proportional to the demand rate and greater than demand rate. the inventory model is developed by considering four different circumstances. the optimal of the problem is obtained with the help of mathematica 7 software. numerical examples are given to illustra...

The purpose of this study was to investigate the photocatalytic oxidation of a reactive azo dye and determine the improvement in the biodegradability when photocatalytic oxidation was used as a pretreatment step prior to biological treatment. The results obtained from the experiments adding H2O2/TiO2 show that the highest decolorisation rate is provided by the combination of (UV+TiO2+H2O2). The...

degradation of o,o-dimethyl -o-4-nitrophenylphosphorothioate (methylparathion) by ozonation in aqueous solution was studied in a batch reactor under constant ozone dosage and variable ph conditions. the effectiveness of the process was estimated based on the degree of cod (chemical oxygen demand) reduction and conversion of methylparathion. it was observed that ozonation is more effective at a...