Adsorption of copper using groundnut seed cake power, sesame seed cake powder and coconut cake powders as bioadsorbents was optimized at a pH of 5, temperature of 40 °C, initial metal concentration of 10 mg/L, contact time of 30 min and adsorbent dosage 0.75 g for groundnut seed cake powder and 1.0 g of sesame seed cake powder and coconut cake powder. From the results of kinetic studies, it was concluded that the adsorption process followed pseudo-second-order kinetics. Langmuir adsorption isotherm fit perfect for the adsorption of Cu(II) using the three adsorbents. Maximum adsorption capacity was found to be 4.24 mg/g. Artificial neural network modeling which was adopted for the predication of adsorption of Cu(II) using groundnut seed cake powder, sesame seed cake powder and coconut cake powder was carried out by using back-propagation algorithm. Correlation plot drawn for the experimental and ANN predicted values showed a strong correlation coefficient of 0.989, indicating that the network trained fit apt for the prediction of adsorption process.

The author's present study was carried out for a period of 3 years from 2010 to 2013 to itemize the various physico-chemical parameters, irrigation water quality parameters and heavy metals in Champavathi River waters at Andra reservoir and Denkada anicut. Water samples were collected from the chosen sampling stations of the two reservoirs for every 4 months and analyzed as per APHA standard methods. The results obtained were compared with IS 10500 standards and found to be well within the prescribed values. Though the obtained values were well within the prescribed standard values, it was found that the water quality index, concentration of certain parameters such as calcium, magnesium, sodium and potassium of the waters of Andra reservoir are higher than that of the Denkada anicut, and the concentration of nitrite was found to be higher in the water sample analyzed from Denkada anicut. Except silicon, all the other metals were found to be below the detection limits in the two reservoir waters. The reasons for the same were probed by the authors in the presented study. From the analysis reports, it was found that the water analyzed from the two reservoirs was fit for irrigation, agriculture, industrial and domestic purposes. Keywords Water quality index Á Physico-chemical characterization Á Andra reservoir Á Denkada anicut Á Vizianagaram Á Irrigation projects

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The present work of the authors is aimed at the assessment of water quality with special reference to fluoride contamination in the two selected villages Mulagada and Yeduruvanipalem. These two villages are situated in the industrial area of Visakhapatnam district of Andhra Pradesh, India. These two villages are surrounded by industries like BHPV, HPCL, Zinc smelter and Coromondel fertilizers. During a preliminary survey in the two villages it was found that the residents of the two villages were suffering from dental flourisis. In view of this, the authors carried out experiments on the determination of physico-chemical characterization. The results were compared with BIS standards. In the two villages, concentration of fluoride was found to be in the range 1.432-2.944 mg/L. Water quality index (WQI) for the two villages was found to be 101.1 for the village Mulagada and 87.5 for the village Yeduruvanipalem. A strong correlation between phosphate and fluoride in the water of the village Mulagada was observed. From the results obtained it was inferred that the water of the two villages is unfit for human consumption.