Studies on Nanostructure, Magnetic Behavior, Optical Properties, and Magnetic Field Sensor Co0.2Fe2.8O4 NanofluidYoni Nur Lutfiyah, Arif Hidayat, Ahmad Taufiq, Ainun Nikmah and ST. Ulfawanti Intan SubadraBIO Web Conf., 183 (2025) 01011DOI: https://doi.org/10.1051/bioconf/202518301011