Different Performances of H2O2 to Oxidise Aldicarb and Hexazinone in the Advanced Oxidation Process of Ozone/Hydrogen Peroxide

The degradations of hexazinone and aldicarb by direct ozonation combined an advanced oxidation process（ AOP） of O3/H2O2 were investigated in this study focusing on the oxidation mechanism by identifying the hydrogen peroxide consumption during the oxidation process of the two chemicals. The results showed that H2O2 could enhance the removal rate of the triazine herbicide hexazinone,and it was consumed along with the variation of removal rate in the light of different pH levels. The addition of H2O2 contributed little to the removal of the thiocarbamate herbicide aldicarb and H2O2 content kept constantly throughout the degradation process. Tert-butyl alcohol（ TBA） effectively scavenged the ·OH radical for hexazinone,but had no effect on the removal rate of aldicarb. Aldicarb removal was mainly attributed to direct ozonation molecule in both O3（ 97.00%） and O3/H2O2（ 96.76%）systems. Moreover,sole O3 could hardly oxidize hexazinone whereas·OH radicals contribute respective 74.70% and 97.50% of removal in O3 system and O3/H2O2 AOP. All of these findings suggest that the mechanism of ·OH radical generation and the chain reaction in O3/H2O2 AOP should be further discussed.     

ENVIRONMENTAL CHALLENGES FACING INDIA

INTRODUCTION India is among one of the ten most industrialized nations in the world. Increase in population has raised the urbar industrial, transport and agriculture demands which are major reasons for the degradation of the environmel condition. For India besides land and soil degradation, deforestation, low accessibility of water, ,industrial pollution and urban congestion are the major environmental issues of priority. The industries that generate huge quantities of waste are thermal power station, Iron and Steel Plants, Sugar, Paper and Fertilizer Industries.     

High mutation rate and predominance of insertions in the Caenorhabditis elegans nuclear genome

Mutations have pivotal functions in the onset of genetic diseases and are the fundamental substrate for evolution. However, present estimates of the spontaneous mutation rate and spectrum are derived from indirect and biased measurements. For instance, mutation rate estimates for Caenorhabditis elegans are extrapolated from observations on a few genetic loci with visible phenotypes and vary over an order of magnitude. Alternative approaches in mammals, relying on phylogenetic comparisons of pseudogene loci and fourfold degenerate codon positions, suffer from uncertainties in the actual number of generations separating the compared species and the inability to exclude biases associated with natural selection. Here we provide a direct and unbiased estimate of the nuclear mutation rate and its molecular spectrum with a set of C. elegans mutation-accumulation lines that reveal a mutation rate about tenfold higher than previous indirect estimates and an excess of insertions over deletions. Because deletions dominate patterns of C. elegans pseudogene variation, our observations indicate that natural selection might be significant in promoting small genome size, and challenge the prevalent assumption that pseudogene divergence accurately reflects the spontaneous mutation spectrum.