INTRODUCTION Arsenic is a chemical element that has the symbol As. Arsenic is widely distributed in nature and is associated with the ores of metals such as gold, lead, and copper. Arsenic also enters the environment through human activities, as arsenic is often used in pesticides, dyes, and chemical weapons. The arsenic compound chromated copper arsenate (CCA) has also been used as a wood pres...

The drinking, borewell and sewage water in the Sanmugasikamani Nadar (S.N) street, Naivatti Nadar (N.N) street and Thiruthangal area of Sivakasi has been studied. The various constituents monitored include the physicochemical characters like pH, total solids, total dissolved solids, total suspended solids; chemical parameters like total alkalinity acidity free CO2, dissolved oxygen, total hardn...

background: the presence of lead in natural waters has become an important issue around the world. lead has been identified as a highly toxic metal that can cause severe environmental and public health problems and its decontamination is of utmost importance. the aim of this work was to evaluate the adsorption of lead (pb(ii)) on waste tea leaves as a cheap purification method. methods: in this...

Djendjen River is one of the largest rivers in the region of Jijel (Algeria). Human activities such as urban discharges, industrial, agricultural, and livestock have significant effects on the quality of water. The present study attempts to evaluate the quality of water along the banks of the Djendjen River at different sampling sites, using physico-chemical and bacteriological methods. The col...

Water quality has an high impact on human health. Chemical mixtures deployed in the environment can lead to multilevel contamination, going from groundwater through surface water, crops, vegetables, livestocks and, finally, humans. Groundwater can be contaminated by the percolation of chemical compounds due to various management errors, which can be mainly re-conducted to vulnerability of the g...

various physico chemical characteristics of the river ganga in varanasi were studied in the oct 2005 to nov 2006. ecological parameters like dissolved oxygen(do), ph, nitrate(no3-), po43- and bacterial population were analyzed and compared with standard permissible limits to assess the best designated use of the river water for various purposes. study revealed that the water quality at varanasi...

Unsafe drinking water is one of the main concerns in developing countries. In order to deal with this problem, a cooperation project was set up by the ACRA Foundation in the Logone valley (Chad-Cameroon). Water supplies were sampled throughout the villages of this area mostly from boreholes, open wells, rivers and lakes as well as some piped waters. The samples were analysed for their physical-...

This work addresses the short-term scheduling of one of the most critical stages in the semiconductor industry, the automated wet-etch station (AWS). An efficient MILPbased computer-aided tool is developed in order to achieve a proper synchronization between the activities of sequential chemical and water baths and limited automated wafer’s lot transfer devices. The major goal is to find the op...

OBJECTIVES To perform a pilot study on bacterial contamination in some dental surgeries (n=51) in a local health unit in Brescia (Lombardy Region, Italy) and to evaluate the procedures to control cross infection used by the personnel to reduce the risk of infection in dental practice. METHODS A survey was carried out by interviewing 133 dental personnel with a questionnaire on the procedures ...