SAHARMAN GEA Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara Indonesia
SRI RAHAYU Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara Indonesia
ANDRIAYANI ANDRIAYANI Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara Indonesia
AVERROES FAZLUR RAHMAN PILIANG Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara Indonesia
NONI OKTARI Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara Indonesia