List of Articles Solid phase extraction Open Access Article Abstract Page Full-Text 1 - Trace Analysis of Pharmaceutical Residues in Wastewater Treatment Plants in Rio de Janeiro, Brazil Aldo Pacheco Ferreira 10.22034/jchr.2018.544050 Open Access Article Abstract Page Full-Text 2 - Selective Dispersive Solid Phase Extraction of Ser-traline Using Surface Molecularly Imprinted Polymer Grafted on SiO2/Graphene Oxide Faezeh Khalilian Feloria Khajoie Kermani 10.22034/jchr.2017.544164 Open Access Article Abstract Page Full-Text 3 - Preparation of Modified Magnetic Nanocomposites Dithiooxamide/Fe3O4 for Preconcentration and Determination of Trace Amounts of Cobalt Ions in Food and Natural Water Samples Ali Mirabi Nafiseh Aliakbari 10.22034/jchr.2016.544156 Open Access Article Abstract Page Full-Text 4 - Perconcentration of Mercury (II) from Natural Water by Activated Charcol -loaded Schiff’s Base 2-Propylpiperidine-1-Carbodithioate (PPCD) Phases A. Moghimi 10.22034/jchr.2012.543977