[1]Department of Chemistry Faculty of Science Lubumbashi University Lubumbashi 1825 D.R. Congo;
[2]Department of Geography Faculty of Science Lubumbashi University Lubumbashi 1825 D.R. Congo;
[3]Department of Geology Faculty of Science Lubumbashi University Lubumbashi 1825 D.R. Congo;
[4]Department of Material Engineering Higher School of Industrial Engineers Lubumbashi University Lubumbashi 1825 D.R.Congo;
[5]Department of Management Faculty of Economics and Management Lubumbashi University Lubumbashi 1825 D.R. Congo;