Fig. 4
From: Photonics and Nanophotonics and Information and Communication Technologies in Modern Food Packaging

Influence of molar mass of PVP on the intensity of luminescence of films. 1 M(PVP) = 10,000 g/mol, 2 M(PVP) = 40,000 g/mol, 3 M(PVP) = 360,000 g/mol, a Samples without ZnO. b [ZnO] = 2 · 10−2 mol/L, λ ex. = 330 nm