Development of New Technique for the Continuous Monitoring Of Chlorine in Drinking Water

ABSTRACT: It is necessary to measure the chlorine level in the water before its use for the drinking purpose.An automated method for routine measurement of chlorine level in water has been developed using photovoltaic detector coupled with a monochromatic pink colored light emitting diode as a source of light. The detected signal has further conditioned and processed by the operational amplifier and ARM processor respectively. The software has been developed for the functions-adjustment of 100% transmittance for reference, measurement of transmitted light intensity and its conversion into absorbance, look-up table of optical densitiesof standard solutions, and finally estimation of unknown concentration. Conventional colorimetric method were simplified for this technique. The technique has the advantage of continuous monitoring and low detection limit. Theanalyzer based on thepresent technique has been successfully used for the monitoring of chlorine level. The analyzeris handheld and suitable for the field work

The effect of hydration on the molecular charge distribution of cations: an ab initio SCRF study

A theoretical study of the changes in the charge distribution of a series of small cations due to the polarization effect of water is presented. The results, which are obtained from high-level ab initio self-consistent reaction field calculations, show the complexity of the solvent effect on the electron distribution of cations. The polarization effect of water on the charge redistribution for cations is smaller than that for anions and neutral molecules, but it is still significant for some systems

In-Vitro Antioxidant Activity, Acute Oral Toxicity Studies and Preliminary Phytochemical Characterization of the Bark Extract of Terminalia arjuna (L.)

The free radicals and the reactive oxygen species (ROS) are known to induce oxidative stress and it has been implicated in the pathology of cardiovascular diseases, inflammatory conditions, cancer and ageing. The activities associated with ROS can bedelayed, prevented or removedby antioxidant compounds (natural or synthetic). The use of synthetic antioxidants restricted because of their known side effects such as liver damage and carcinogenesis. The aim of this study to evaluate in vitro antioxidant and acute oral toxicity of Terminalia arjuna extracts. The present finding reveals that the purified fraction at100 µg/ml, showed maximum (91.32 ± 0.10 %,) DPPH radical scavenging effect in comparison with standard ascorbic acid (79.46 ± 0.10%) at the 10 µg/ml concentration. The reducing power of the purified extract was found to be dose dependent. Food and water intake of the animals in test and control groups was found normal during the 14 day acute oral toxicity studies and no apparent changes were observed in the internal organs of both, the test and control groups, after gross necropsy. The preliminary phytochemical screening of the crude acetone extract revealed dominant presence steroids, terpenoids, polyphenols, alkaloids and tannins. TLC profile of the purified fraction revealed a single band of Rf 0.38, a characteristic feature of triterpenoids. The UV absorption maximum of the purified fraction was recorded at 194nm. The FT-IR spectrum indicated presence of aromatic rings 3421 (COOH), 2957 (alkanes, CH2 and CH3), 1726 (carbonyl), 1599 (carboxylic acid), and region between 1000-1300 stretching of C-O, ester and ether carboxylic group. Thus, the isolated bioactive phytoconstituents form the bark extract of Terminalia arjuna could be used as natural anti-oxidants.