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Here, it was explored how europium ions affected the physical, structural, and optical properties of alkali lead borotellurite glasses. The glasses were made using the standard melt quenching technique, and their structural properties were investigated using X-ray diffraction and Raman spectroscopy techniques. The physical properties of ready glasses were evaluated by quantifying density variations using the Archimedes approach. Using the Davis-Mott approach, optical properties such as optical energy band gap and Urbach energy were identified. The analysis of the refractive index, dielectric constant, molar refraction, and molar polarizability are reported. According to the results, the recently studied alkali lead boro tellurite glasses have demonstrated potential uses in the fields of optical materials

The study of polarizability, optical basicity, and electric susceptibility carried out on the new and very rare set of bismuth - tellurite glasses doped with Ho3+ ions were fabricated by the conventional melt quenching process. The non-crystalline nature was confirmed by X-ray diffractometer measurements. Physical properties such as rare earth ion concentration, interionic distance, polaron radius, and average tellurium - tellurium separation were investigated by appropriate formulae. By UV absorption spectra, optical properties of Ho3+ ions doped glasses were found in the wavelength limit from 400 to 700 nm. The optical properties like optical dielectric constant, electronic polarizability, metallization criterion, electronegativity, optical basicity, and electric susceptibility were measured with appropriate mathematical relations. The impact of Ho3+ ions on nonlinearity in optical parameters discloses bismuth tellurite glass as a new applicant for holmium doped fiber amplifier applications.

The DC conductivity of Eu3+ ions embedded in lead boro-tellurite glasses has been accomplished as a function of temperature in the range of 343–483 K. The Cole-Cole (Impedance) plots of glasses contained only one perfect semicircle at different temperatures. This realizes the material's conductivity which presumes an ideal Debye type relaxation. In the Cole-Cole plot at 483 K, the semicircle is well defined and fitted into an equivalent parallel RC circuit. The DC conductivity exhibits the Arrhenius behavior and compositional dependence. The DC activation energy (Edc) was estimated for all samples by using linear regression analysis. The values range from 0.202 to 0.231 eV.

Six glass samples composes the (70-y) B2O3-15TeO2-10Na2O-5PbO-yEu2O3, where y = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5 mol%, have been synthesized by conventional melt quenching technique. The properties such as the structural, thermal and spectroscopic properties were studied by employing the suitable characterizations tools, such as X-ray diffraction, differential scanning calorimetry, Raman spectroscopy, fourier transform infrared spectroscopy, magic angle spinning nuclear resonance spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The XRD, SEM and EDS confirm non-crystalline nature, microstructural and homogeneous, absence of impurity of glass samples, respectively. The DSC data reveals the good thermal stability of glasses. The FT-IR and Raman studies reveal the contribution of boron and tellurium in the network of prepared glasses, the presence of BO3, and BO4, a small amount of six-member boroxol rings, TeO3 and TeO4 structural groups. The MAS-NMR studies reveal the presence of quadrupolar interaction of BO4 and quadrupolar broadening of BO3 in all glasses and it also discloses the fact that only a small amount of BO4 is converted into BO3 during structural evolution.

Lead boro-tellurite glasses activated with europium oxide were synthesized with the aid of conventional melt quenching mode. Physical properties such as density and molar volume as a function of Eu2O3 concentration were determined. Structural studies have been done through X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FTIR). Morphological and luminescent properties have been analysed with Scanning Electron Microscopy (SEM) and spectrofluorometer, respectively. Non-crystalline character was proved by XRD and the surface morphology by SEM technique. Five luminescence emission bands were observed at different wavelengths when excited by 394 nm. The most intensive emission peak was positioned at 612 nm (red) due to 5D0 →7F2 transition of Eu3+ ion. Judd-Ofelt (JO) theory was applied to estimate various radiative parameters and to decide the suitability of the glass for technological applications. JO and the CIE Chromaticity values reveal the investigated glasses are promising materials for electro-optic applications.

The glasses of composition 20TeO2-15Bi2O3-(65-x)V2O5-xLi2O (x=10,15,20 and 25 mol%) have been prepared using the conventional melt quenching technique and their thermal structural and electrical properties were investigated through differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) and Impedance spectroscopy, respectively. The glass transition temperature increases with Li2O content and their values ranging from 250 to 274°C. The difference between the crystallization temperature and the glass transition temperature, ΔT=Tc-Tg, have also been found that increasing with Li2O content. The increasing glass transition temperature and ΔT values are indicated that the increase of the thermal stability and rigidity of the glasses with increasing Li2O. The high temperature electrical conductivity has been analyzed using Mott’s small polaron hopping model and activation energy values were determined.The glasses of composition 20TeO2-15Bi2O3-(65-x)V2O5-xLi2O (x=10,15,20 and 25 mol%) have been prepared using the conventional melt quenching technique and their thermal structural and electrical properties were investigated through differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) and Impedance spectroscopy, respectively. The glass transition temperature increases with Li2O content and their values ranging from 250 to 274°C. The difference between the crystallization temperature and the glass transition temperature, ΔT=Tc-Tg, have also been found that increasing with Li2O content. The increasing glass transition temperature and ΔT values are indicated that the increase of the thermal stability and rigidity of the glasses with increasing Li2O. The high temperature electrical conductivity has been analyzed using Mott’s small polaron hopping model and activation energy values were determined.

To investigate the structural consequences of Eu3+ ions on alkali boro tellurite glasses, the set of six glass samples of (70-x) B2O3-15TeO2-10Na2O-5PbO-xEu2O3 with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol% glasses were prepared by conventional melt quenching method and X-ray diffraction characterization of the glasses admits the amorphous structure. Also their structural properties were studied by the help of FTIR and Raman spectra. FTIR measurements revealed that the bond structure of the prepared glasses is based on BO3 and BO4 units sitting in different structural groups and also interlinked by TeO3 and TeO4 groups. By Raman spectra, it is clear that the prepared glass samples possessing the boroxol rings and also found that slight variations in glass network of the system is discussed with the variation of Eu3+ ions.To investigate the structural consequences of Eu3+ ions on alkali boro tellurite glasses, the set of six glass samples of (70-x) B2O3-15TeO2-10Na2O-5PbO-xEu2O3 with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol% glasses were prepared by conventional melt quenching method and X-ray diffraction characterization of the glasses admits the amorphous structure. Also their structural properties were studied by the help of FTIR and Raman spectra. FTIR measurements revealed that the bond structure of the prepared glasses is based on BO3 and BO4 units sitting in different structural groups and also interlinked by TeO3 and TeO4 groups. By Raman spectra, it is clear that the prepared glass samples possessing the boroxol rings and also found that slight variations in glass network of the system is discussed with the variation of Eu3+ ions.

Holmium doped bismuth-Tellurite glasses of composition 85TeO2 - (15- x Bi2O3) - x Ho2O3, (x=0.1, 0.2, 0.3, 0.4 and 0.5 mol %) were prepared using the conventional melt quenching method. For the optical applications, it is very important and essential to find the optical and physical properties of prepared glasses. The influence of Ho3+ ions on the optical properties of Bismuth - Tellurite glasses was studied through UV absorption spectra. In the UV-visible region of wavelength 200-1100 nm, absorption spectra were recorded at the room temperature. The physical properties such as refractive index, molar refraction and polarizability of prepared set of glass have been calculated by using Lorentz–Lorentz relations. By the absorption edge studies, the values of optical bandgap energies have been evaluated. With respect to small variation of holmium (Ho3+) ion concentration the non-linear variations of the above optical parameters were discussed.

The influence of Eu3+ ions on the Optical properties of Boro Tellurite Glasses of (70-x) B2O3−15TeO2−10Na2O− 5PbO-xEu2O3 with x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol% glasses were prepared by conventional melt quenching method and their physical and optical properties were investigated by using UV absorption spectra, which was recorded at room temperature in the UV-visible region of wavelength 200-1100 nm. By the absorption edge studies, the values of optical bandgap energies have been evaluated. The direct and indirect bandgap values ranges between 3.362 to 3.650 eV and 2.011 to 2.863 eV respectively. The refractive index, molar refraction and polarizability of oxide ions have been calculated by using Lorentz–Lorentz relations. The refractive index and molar refraction values were ranges from 2.241 to 2.358 and 76.147 to 79.915 cm3 respectively. The non-linear variations of the above optical parameters were discussed with respect to small variation of europium (Eu3+) ion concentration.The influence of Eu3+ ions on the Optical properties of Boro Tellurite Glasses of (70-x) B2O3−15TeO2−10Na2O− 5PbO-xEu2O3 with x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol% glasses were prepared by conventional melt quenching method and their physical and optical properties were investigated by using UV absorption spectra, which was recorded at room temperature in the UV-visible region of wavelength 200-1100 nm. By the absorption edge studies, the values of optical bandgap energies have been evaluated. The direct and indirect bandgap values ranges between 3.362 to 3.650 eV and 2.011 to 2.863 eV respectively. The refractive index, molar refraction and polarizability of oxide ions have been calculated by using Lorentz–Lorentz relations. The refractive index and molar refraction values were ranges from 2.241 to 2.358 and 76.147 to 79.915 cm3 respectively. The non-linear variations of the above optical parameters were discussed with respect to small variation of europium (Eu3+) ion concentration.

Glasses of the composition xPr6O11- (35-x)TeO2-65B2O3 (x=0, 0.1 to 0.5 mol %) have been prepared using the melt quenching method. The ac and dc conductivity of glass have been measured over a wide range of frequencies and temperatures. Experimental results indicate that the ac conductivity depend on temperature, frequency and Praseodymium content. The conductivity as a function of frequency exhibited two components: dc conductivity (σdc), and ac conductivity (σac). The activation energies are estimated and found to be decreases with composition. The impedance plot at each temperature appeared as a semicircle passes through the origin.

The relationship between the catch of male Spodoptera litura (F.) moths in sex pheromone‐baited traps and the number of egg‐masses in groundnut crop at the International Crops Research Institute for Semi‐Arid Tropics Centre Patancheru, India was examined during the post‐rainy season of 1983. Significant positive correlations were found between the number of egg‐masses and the total number of male moths caught during the 7 days preceding the egg‐mass count. 75% of the variance in the egg‐mass counts and pheromone trap catches could be accounted for by the regression.