Removal of Cd(II), Pb(II), Hg(II), Mn(II), Ni(II) and Zn(II) by chemically (Na2S) treated granular activated carbon (GAC)has been found to be concentration, pH, contact time, adsorbent dose and temperature dependent. Adsorption isotherm studiesindicated that adsorptive behaviour of metal ions on chemically treated GAC satisfies Langmuir assumptions.

In the present study, samples of ground and wastewater were collected from Pali, Rajasthan and analysed for relevant parameters. The results of the analysis of ground and wastewater showed the high range of toxic heavy metals and other parameters in the ground used for potable purposes.

The author brings out that the scientific evidence is now overwhelming: climate change presents very serious global risks, and it demands an urgent global response. The range of climatic changes anticipated - will have real impacts on the natural environment as well as man-made infrastructure and their ability to contribute to economic activity and quality of life.

Hydrogen is a new, highly versatile energy carrier which is a clean, safe and cheap fuel choice and when combined with super-efficient fuel cell vehicles, enables a profitable transition from the present hydrocarbon based fuel economy.