1. Clausthal Technical University Department of Mineral and Waste Processing Walther-Nernst-Straße 9 38678 Clausthal-Zellerfeld Germany
2. Qingdao University New Energy Vehicle Research Center 308 Ning Xia Road Qingdao China
3. Federal Institute for Geoscience and Natural Resources (BGR) Stillweg 2 30655 Hannover Germany