Assessment of groundwater contamination in a suburban area of Chennai,Tamil Nadu,India

Groundwater source is the major source of drinking water in most of the suburban areas of India. Groundwater quality was analyzed for pH, TDS, hardness, chloride, fluoride, nitrate, ammonia, phosphate, total coliform and E. coli for the period of January–December 2013. Samples were collected from 10 locations that include 10 shallow wells and 10 deep wells in each location. The quality variation between both shallow and deep wells during pre- and post-monsoon was analyzed. The improper disposal of solid waste and the distance of septic tank were pronounced on E. coli count. The analysis reveals that groundwater contamination is influenced by seasonal changes, environmental condition of the well and maintenance of the well. The high contamination was observed in the wells which are near to the Pallikaranai marsh, and during post-monsoon season, the total dissolved solids and nitrite parameters are slightly increased, whereas chloride increases during pre-monsoon season. Correlation analysis reveals that the chloride and nitrite have a significant relation. The results suggested that the groundwater immediately needs broader protection.     

A relationship between the natural radioactivity and mineralogical composition of the Ponnaiyar river sediments, India

The natural radiation level has been determined for the sediment samples of Ponnaiyar River, India with an aim of evaluating the radiation hazard. The average activity concentrations are within the world and Indian average values although some extreme values have been determined. The magnetic susceptibility measurement has been carried out to know the magnetization nature of the sediments. More downstream (mouth) of the river has quite higher magnetic susceptibility values. The mineralogical characterizations of the sediments have been carried out using Fourier Transform Infrared (FTIR) spectroscopic and XRD technique. The minerals such as quartz, microcline feldspar, orthoclase feldspar, kaolinite, calcite, gibbsite, montmorillonite, smectite, palygorskite and organic carbon are identified from FTIR analysis. Few minerals like zircon, monazite and hornblende are identified only in XRD analysis. The relative distribution of major minerals is determined by calculating extinction coefficient. The calculated values show that the amount of quartz is greater than microcline feldspar and very much greater than kaolinite in all the sites. The content of quartz and microcline feldspar is decreases, and kaolinite gradually increases towards the river mouth. Multivariate Statistical analyses were carried out between the parameters obtained from radioactivity analysis and other analyses to know the existing relations. Obtained results are discussed and suggested that the natural radioactivity level of the present sediments is mainly controlled by clay content and lesser extent to magnetic susceptibility.     

Review on phase change materials for solar energy storage applications

Environmental Science and Pollution Research - The energy storage application plays a vital role in the utilization of the solar energy technologies. There are various types of the energy storage...