Synthesis of Ferromagnetic Nanocomposites from Nanocrystalline Cellulose and Characterization as an Adsorbent to Remove Lead in the Water oleh Bao Tran Pham Ngoc, Ngoc Han Tran Thi, Thanh Son Dinh, Nhan Tu Le Tan, Nguyen Phuc Thien Le, Thanh Phong Mai, Dinh Quan Nguyen