Synthesis and characterization studies of pure and Ni doped CuO nanoparticles by hydrothermal method oleh M. Chandrasekar, M. Subash, S. Logambal, G. Udhayakumar, R. Uthrakumar, C. Inmozhi, Wedad A. Al-Onazi, Amal M. Al-Mohaimeed, Tse-Wei Chen, K. Kanimozhi