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This article describes the synthesis of 1-(((4-nitrophenyl)imino)methyl)naphthalen-2-ol Schiff base (H4NA) and its organyltellurium(IV) complexes and characterization via numerous physical and spectral techniques like MS, FT-IR, UV–Vis, 1H-NMR, 13C-NMR, EDX, Powder XRD, TG-DTG and molar conductance measurements. The characterization results indicate that the Schiff base is bidentate in nature and the complexes adopt distorted square pyramidal geometry. In vitro antioxidant and antimicrobial evaluations indicate that the biological efficacy of the Schiff base was enhanced on chelation. Complexes 4b, 4d and 4f exhibited the highest scavenging efficacy with the lowest IC50 value. While, the antimicrobial examination indicated the more inhibitory property of 4b, 4c and 4e complexes against all the screened microbial organisms. The molecular docking analysis of compounds on the catalytic site of Pseudomonas aeruginosa (2UV0) reveals favorable interactions and supports the good biological response against 2UV0. Further, to support the experimental findings, the molecules were theoretically examined using quantum chemical calculations. The FMO studies was performed on B3LYP/6-31G*, to validate the increased bioactivity of the complexes as compared to the Schiff base. MESP of the compounds identified their highly reactive regions. The hyper-conjugative interactions and second-order perturbation interaction energy of the compounds have been calculated with the help of NBO analysis. The anticipated ADMET characteristics of the compounds were consistent with Lipinski's and other restrictive rules indicating that they can function as effective inhibitors. [ABSTRACT FROM AUTHOR]

The present paper reports the synthesis, photoluminescence (PL), and thermoluminescence (TL) studies of Eu-doped yttrium oxide (YO) phosphor using inorganic materials like YO, flux calcium fluoride, and europium oxide. The sample was prepared by the modified solid state reaction method, which is the most suitable for large-scale production. The prepared phosphor sample was characterized using powder X-ray diffraction, field emission gun scanning electron microscopy, high resolution transmission electron microscopy, Fourier transform infrared spectroscopy , PL, TL, and Commission Internationale de I'Eclairage techniques. The PL emission was observed in the range 417-632 nm ranges all visible regions for the YO phosphor doped with Eu. Excitation spectrum found at 254 nm. Sharp intense peaks found around 467, 534, 594, 612, and 632 nm with high intensity. From the XRD data, using the Scherer's formula, the calculated average crystallite size of Eu-doped YO phosphor is around 45 nm. TL study was carried out for the phosphor with UV irradiation. The present phosphor can act as single host for white light emission in display devices. [ABSTRACT FROM AUTHOR]

In this paper we review the luminescence properties of Pr-doped CaTiO phosphors, the different methods of sample preparation, and characterization of the materials by use of different techniques, for example X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermo-gravimetric analysis, and atomic force microscopy. Solid-state, sol-gel (SG), and combustion methods are most often used for preparation. The high calcining temperature of the solid-state method can be reduced by addition of rare earth oxides (lanthanide series) LnO and LuO. By use of tetra- n-butyl titanates and calcium nitrates as raw material in the modified solid-state method the luminous properties of samples can be optimized at lower sintering temperatures (600 °C) in less time. SG procedures lead to substantial reinforcement of red photoluminescence intensity so can be regarded as the best technique for phosphor preparation. [ABSTRACT FROM AUTHOR]

The present paper reports the thermoluminescence (TL) glow curve of Eu-activated SrAlO phosphor with different UV exposure times. Evaluation of kinetic parameters was done by the peak shape method. The recorded glow curve shifts towards lower temperatures with respect to increasing UV exposure time. The peaks were found at 146.76, 141.34 and 140.37 °C, respectively, for 5, 10 and 15 min of UV exposure using the heating rate of 3°C s. The glow peak shows the second-order kinetics. Different kinetic parameters, i.e. trap depth, order of kinetics, activation energy, and frequency factor are also calculated. The XRD pattern of the sample is compared with reported XRD using the software match. [ABSTRACT FROM AUTHOR]