INTERNATIONAL JOURNAL OF CHEMICAL AND PHYSICAL SCIENCES

1-18

Authors: JADHAO R. K. * DAWANDE S. D.

The major reason of this study was to examine the effect of HRT and SRT on parameters such as chemical oxygen demand (COD), soluble COD (Sol.COD), biochemical oxygen demand (BOD), nitrogen (ammonia NH4, nitrate NO3) contents and phosphorus contents (Phosphate PO4), total suspended solids (TSS) and volatile suspended solids (VSS), soluble microbial products (SMP), proteins, carbohydrates, acetate and alkalinity (ALK) for hospital wastewater and residential quarter wastewater. The experiments have been carried out on laboratory-scale hollow fiber submerged membrane bioreactor (MBR) for summer season. The results have shown a high removal efficiency of COD, BOD and ammonia which ranged between 92.51 to 97.95 %, 93.10 to 97.63 % and 97.70 to 98.67 %, respectively. While, for TSS and VSS, the removals were found to reach almost 100 %. Comparatively, the phosphorus removal efficiency (54.50 to 57.95 %) was found inferior than other parameters.

26-35

Authors: RATHORE V.

This Paper gives the connection between the polarization of ions and the repulsive force between them. We have investigated the phonon dynamics of Polarizable Materials in NaCl phase using Rigid Shell Model with pair wise interionic interaction potential. The potential consist of the long -range Coulomb and three-body interactions and the short -range van der Waals interaction and the Hafemeister and Flygare type overlap repulsion extended up to the second neighbor ions. The present model basically includes the effect of charge transfer caused by the electron-shell deformation of the overlapping ions in the frame work of both ions polarizable. this takes account of the polarizability of ions for vibrations of all wavelengths. There is generally good agreement between the measured dispersion relations and the dispersion relations calculated on the simple version of the shell model-Coulomb forces between ions of unit charge with the iodine atoms polarizable and central repulsive forces between first neighbors only, acting through the iodine shell. The elastic constants obtained from the model have been used to calculate the phonon dispersion relation in the symmetry direction .