Nguyen NN. ENGINEERING THE NaYF4:Yb3+/Tm3+ UPCONVERSION NANOPARTICLE LUMINESCENCE ENERGY TRANSFER FOR A RATIOMETRIC pH INDICATOR. DLU JOS [Internet]. 2022 Nov. 24 [cited 2025 Nov. 16];13(1):71-82. Available from: https://tckh.dlu.edu.vn/index.php/tckhdhdl/article/view/1044