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The melt quench approach is used to create a transition metal-doped glass material by adjusting the concentration of vanadium and lithium carbonate with a unique chemical composition. The main objectives of the present investigation are to identify basic structural units in the prepared samples, to investigate the impact of glass composition on structural changes, to relate the structural changes with the change in properties of glasses, and to find the suitability of the samples from the perspective of optical applications. The main novelty of these glasses is that the lithium carbonate is varied along with the V2O5 for optical applications. The highest dopant 1 mol percent material has a density of 3.6666 gm/cc and a refractive index of 1.56, indicating its suitability for optical applications. The glass melting temperature (Tg) of the test sample is 808.09 °C, and Hruby's criteria value (KH) is 0.2565, inferring that the glass material is stable. For loads of 50 g and 100 g, the Vickers micro-hardness improved when the dopant was increased, while for 200 g, the hardness value declined. As the stress on the material rose from 10 to 30 N, the coefficient of friction drops from 0.632 to 0.002, the specific wear rate increased from 6.64 × 10−5 to 39.06 × 10−5 mm3/N-m, and the specific wear energy decreased from 22.44 to 0.81 MJ/g. In the visible area, the material's optical absorption for the greatest dopant is 548 nm, and in the infrared region 738 nm. The direct and indirect band gaps of the current investigated material for the highest dopant are 2.03 eV and 1.88 eV, respectively, proposing that the sample is a semiconductor. Optical transmission measures find the material's suitability as a bandpass filter in the visible range at 415.33 nm and 417 nm, respectively, with FWHW of 0.35 nm and 1.22 nm for the highest dopant sample. [ABSTRACT FROM AUTHOR]

Green and efficient one-pot three-component synthesis of novel 2-(7-amino-2,2-dimethyl-4-oxo-5-phenyl-4,5-dihydropyrano[2,3- d][1,3]dioxin-6-ylcarbonyl)-2,3-dihydrophthalazine-1,4-diones have been developed by condensing 3-(1,4-dioxo-1,2,3,4-tetrahydrophthalazin-2-yl)-3-oxopropanenitrile with benzaldehydes and Meldrum's acid using L-proline as catalyst in ethanol at room temperature. The products have been isolated as pure compounds in good yields without using column chromatography. [ABSTRACT FROM AUTHOR]

A blue colored Cu-doped lead zinc phosphate glass in the system 10 PbO-30 ZnO-59.9 PO-0.1 CuO was prepared by quenching of the melt and spectral properties of these glasses were studied. Optical absorption and electron paramagnetic resonance spectra of Cu ion in these glasses were measured. Polarization produced by uneven distribution of d-electron density on the inner core of s-electron was studied. The estimated results showed that the g > g because Cu ions had tetragonally elongated distortion. Optical absorption studies also supported the same property. The variation in crystal field caused the change in bonding nature. The Fourier transform infrared spectra had elucidated the bonding system of the constituent atoms and groups that shed light on the expected structure. Raman spectra were used to get information about the depolymerization of phosphate chains in the glasses with successive replacement of alkali content. [ABSTRACT FROM AUTHOR]

X-Ray diffraction, energy dispersive X-ray, Fourier transform infrared, Raman spectroscopy, differential scanning calorimetry, UV-Visible spectroscopy and electron paramagnetic resonance spectroscopic studies have been carried out on alkali earth lead zinc phosphate glasses doped with 0.1 % chromium ions. The energy dispersive X-ray spectra reveal fundamental compositional information of the glasses. Infrared spectra indicate that phosphate network is depolymerized with progressive substitution of alkali earth content and inform the characteristic vibrations of PO units. Raman spectra suggest that these glasses are consisting of metaphosphate [Q] units along with some bands related to pyrophosphate [Q] and orthophosphate [Q] units. The crystal-field parameter and inter-electronic repulsion parameters have been evaluated from optical absorption spectral data. Electron spin resonance spectra of Cr systems indicate that g > g and Cr ions are located at sites with lower symmetry. It is obtained that the glass transition temperatures fall in region of 377-360 °C. Increase in density of the glass system brings changes in structure of the glasses on replacement of alkali earth content. [ABSTRACT FROM AUTHOR]

Investigation for high yielding water wells in the khondalitic terrain (graneti ferrous silliminite gnesiss) is mostly faced with the problem of identification of the extent of the depth of kaolinisation of the aquifer. The traditional Vertical Electrical Sounding survey, Seismic Refraction survey and Very Low Frequency Electromagnetic survey could not identify the kaolinisation of the aquifer in the present investigations. The Two Dimensional (2D) Resistivity and Induced Polarization (IP) Imaging surveys are attempted for the identification of kaolinised layer and depth of kaolinisation. Number of 2D Resistivity and IP Imaging profiles were conducted near Chipurupally in Vizianagaram district of Andhra Pradesh, India along successful and failed wells located within short distances. Resistivity and IP measurements were carried out using an ABEM SAS 4000 Terrameter. The resistivity and I.P. images have provided a clear view of the thickness of the highly weathered zone (kaolinised zone) at both successful and failed wells. The highly weathered zone is identified with the resistivity values below 25 ohm.m. The depth of highly weathered material at failed well is extended about 8-10 m more deeper than the successful wells at some places to as much as 20 m more deep at some other places. This extended deeper kaolinisation of the aquifer is responsible for failure of wells. Layers having resistivities between 25-65 Ohm.m are identified as aquifer layers which are composed of moderately weathered and fractured khondalitic suit of rocks (Garnti ferrous sillimanite/biotite gneiss). Layers with resistivities greater than 65 Ohm.m are interpreted to have basement characteristics belonging to the granite gneiss. Interestingly IP imaging has not provided any greater insights in delineating the kaolinistion of the aquifer when compared to resistivity Imaging, in fact resitivity imaging has shown greater depths of kaolinisation than IP Imaging. [ABSTRACT FROM AUTHOR]

This study discusses the impact of high-resolution winds on the coastal waves and analyses the effectiveness of the high-resolution winds in recreating the fine-scale features along the coastal regions during the pre-monsoon season (March–May). The influence of the diurnal variation of winds on waves is studied for the Tamil Nadu coastal region using wind fields from weather research and forecast (WRF) (3 km) and European Centre for Medium-Range Weather Forecasts (ECMWF) (27.5 km). The improvement in the coastal forecast is then quantified with wave rider buoy observations. The high-resolution wind fields simulated fine-scale features like land–sea breeze events and showed good agreement with observation results. The error in the wave height and period is reduced by 8% and 46%, respectively, with the use of high-resolution forcing winds WRF over ECMWF, although the overestimation of wave energy on high frequencies due to overestimated WRF winds remains as a challenge in forecasting. The analysis also shows the importance of accurate wave forecast during a short-duration sudden wind (~12 m/s) occurrence in southern Tamil Nadu near Rameswaram during the pre-monsoon period. Low pressure forms over Tamil Nadu due to the land surface heating, resulting in a sudden increase of winds. High winds and steep waves which cause damage to the property of the coastal community near Rameswaram also were well simulated in the high-resolution forecast system with WRF winds. [ABSTRACT FROM AUTHOR]