The present paper deals with the functionalization of psyllium with acrylamide under the influence of gamma radiation using hexamethylene tetramine as a crosslinker. The polymer synthesized was characterized using FTIR spectroscopy, scanning electron microscopy and thermogravimetric analysis. The superabsorbent was then used further for the selective absorption of water from different oil–water emulsions.

Fluorophosphate (PAKCLf: P$_2$O$_5$–Al$_2$O$_3$–K$_2$O–CaF$_2$–LiF) glasses with Dy$^{3+}$ concentration of 0.01, 0.05, 0.1, 0.5, 1.0, 2.0 and 3.0 mol% were fabricated by pouring the melt and sudden quenching process. The glass stability factor of 106°C was calculated by glass transition (563°C) and crystallite (669°C) temperatures. The energy bandgap (E$_g$) of Dy$^{3+}$:PAKCLf glasses is calculated for (${\alpha}$hm)$^2$ (direct) and (${\alpha}$hm)$^{1/2}$ (indirect) allowed transitions. From optical absorption, the oscillator strength and spectroscopic intensity (${\Omega}_{2,4,6}$) parameters by performing Judd–Ofelt calculations were estimated to evaluate the radiative transition properties of ${}^4$F$_{9/2}$ level in Dy$^{3+}$ ions. The emission spectra consist of two intense bands in blue (485 nm: ${}^4$F$_{9/2}$${\rightarrow}$${}^6$H$_{15/2}$) and yellow (576 nm: ${}^4$F$_{9/2}$${\rightarrow}$${}^6$H$_{13/2}$) regions by stimulating at 349 nm. The decay curves demonstrate the non-exponential nature from 0.5 to 3.0 mol% of Dy$^{3+}$ and fitted well to the Inokuti–Hirayama model. The findings of stimulated emission cross-section (5.20 ${\times}$ 10$^{–21}$ cm$^2$), optical gain (29.59 ${\times}$ 10$^{–25}$ cm$^2$s), and quantum efficiency (97%) for Dy$^{3+}$:PAKCLf glasses could be potentially utilized as optical devices. The photometric parameters like CIE colour coordinates and correlated colour temperatures (CCT:6300-6900 K) of Dy$^{3+}$:PAKCLf glasses reveal the application of white light-emitting diodes.