A5003407818- Luminescence Properties of Advanced Materials
- Advanced Combustion Engine Technologies
- Biodiesel Production and Applications
- Multiferroics and related materials
- Ferroelectric and Piezoelectric Materials
- Thermal Expansion and Ionic Conductivity
- Catalytic Processes in Materials Science
- Vehicle emissions and performance
- Quantum Dots Synthesis And Properties
- Thermochemical Biomass Conversion Processes
- Advanced Condensed Matter Physics
- Rare-earth and actinide compounds
- Dielectric properties of ceramics
- Forest Biomass Utilization and Management
- Iron-based superconductors research
- nanoparticles nucleation surface interactions
- Energy and Environment Impacts
- ZnO doping and properties
- Magnetic and transport properties of perovskites and related materials
- Nuclear materials and radiation effects
- Anaerobic Digestion and Biogas Production
- High-pressure geophysics and materials
- Microwave Dielectric Ceramics Synthesis
- Polymer Foaming and Composites
- Topological Materials and Phenomena
Siksha O Anusandhan University
2021-2023
Vellore Institute of Technology University
2023
Bhabha Atomic Research Centre
2011-2019
Lawrence Berkeley National Laboratory
2015
UGC DAE Consortium for Scientific Research
2013
Indian Institute of Technology Kharagpur
2009
University of Twente
1994
Deen Dayal Upadhyaya Gorakhpur University
1990-1991
We report on high-pressure powder synchrotron x-ray diffraction studies $M$Fe${}_{2}$As${}_{2}$ ($M$$=$Ba, Ca) over a range of temperatures and pressures up to about 56 GPa using membrane diamond-anvil cell. Our data indicate phase transition collapsed tetragonal in both compounds upon compression. The at 300 K are measured pressure-increasing -decreasing cycles. measurements show that the Ba compound, occurs 27 GPa, which is much higher than pressure 1.7 Ca compound. At low temperature, we...
Chromium-doped multiferroic bismuth ferrite BiFe1-xCrxO3 (x = 0.00, 0.01, 0.03, 0.05 and 0.07) nanoparticles (NPs) were synthesized by an ethylene glycol-based sol-gel technique annealed at relatively low temperature of 550 °C. X-ray diffraction (XRD) confirmed the phase purity pristine BiFeO3 1% Cr-doped NPs. However, a slight impurity started to appear in 3% BFO which became significant 5% 7% samples. The crystallite sizes as determined Scherrer equation found be 46 nm, 44 39 37 34 nm...
In this communication, we report details of structural, magnetic, and dielectric properties multiferroic Bi7Fe3Ti3O21 at cryogenic temperatures. The low temperature impedance spectroscopic studies showed a relaxor-like anomaly which follows Vogel-Fulcher relation with freezing (TVF) 33 K. Temperature field dependent magnetization indicate the onset possible antiferromagnetic ordering below 150 Variable powder neutron diffraction no structural change down to 22 appearance along evidence...
Optical emission spectra of nanocrystalline zinc gallate (ZnGa2O4) and trivalent chromium ion doped (ZnGa2O4:Cr3+) are reported for different concentrations the dopant ion. The measurements have been carried out over temperature range between 77 296 K. spectrum ZnGa2O4 shows two broad peaks. intensity variation in these peaks, with temperature, is indicative effect symmetry breaking electronic band structure samples. In addition, we find that relative intensities sharp spectral lines Cr3+...
Herein we report the structure, magnetic and dielectric properties of Y 2 CoMnO 6 ( YCMO ) NiMnO YNMO prepared under various conditions. On annealing in inert atmosphere, sample shows a partial decomposition while remains unaffected. Both samples show paramagnetic to ferromagnetic transition around 80 K, but only depend on preparation antiferromagnetic ground state zero field metamagnetic at relatively low (~2 T). Differences environment do not destroy initial antiparallel spin order ,...
In order to identify and quantitatively analyze the anharmonicity of phonons relevant anomalous thermal expansion in $\mathrm{I}h$ phase ice, we performed neutron inelastic scattering measurements study phonon spectrum as a function pressure up 1 kbar at 225 K deuterated ice (${\mathrm{D}}_{2}\mathrm{O}$), temperature over 10--225 ambient both ${\mathrm{H}}_{2}\mathrm{O}$ ${\mathrm{D}}_{2}\mathrm{O}$ ice. We also density functional theory calculations lattice dynamics. The is reproduced from...
We have carried out high temperature Raman spectroscopy studies on a technologically important material Li0.12Na0.88NbO3 (LNN12) in wide range from 298 K to 1073 K. The variations of mode frequencies and full width at half maximum point towards various structural transitions this range. A new which appears around 650 cm−1 473 has been found anomalous dependence. Furthermore, the symmetric stretching asymmetric modes opposite dependence some ranges. At highest (in cubic phase), there are two...
The photo and electro properties of luminescence in ZnS:Pr ZnS:(Cu,Pr) phosphors are studied. voltage frequency variation EL brightness agreement with acceleration-collision mechanism Schottky barrier at the metal semiconductor interface. Photoluminescence (PL) electroluminescence (EL) spectra have been recorded results discussed light existing models.
We present a high-resolution single crystal x-ray diffraction study of Kagome superconductor \cvs, exploring its response to variations in pressure and temperature. discover that at low temperatures, the structural modulations electronic superlattice, commonly associated with charge density wave order, undergo transformation around $p \sim$ 0.7 GPa from familiar $2\times2$ pattern long-range ordered modulation wavevector $q=(0, 3/8, 1/2)$. Our observations align inferred changes CDW prior...
Knowledge of the symmetry and distribution atoms in unit cell bonding between is key point for understanding, designing manipulating chemical behavior or physical prope...
There is a wide range of biomass feedstock readily accessible for harvesting energy in the form solid, liquid, and gaseous fuels that are used thermal power production approaches.
We have prepared ZnSe (luminescent grade) phosphor doped with Sn and (Sn,Pr) varying concentration in an inert atmosphere a silica tubular furnace at temperature of (780 ± 20) °C for 1 hr to obtain ZnSe:Sn ZnSe: phosphors. The photo luminescence (PL) electroluminescence (EL) spectra these phosphors been studied room results were discussed the light existing models. Dependence EL emission on voltage frequency has also carried out. It is found that plot between integrated intensity versus...
This article is devoted to the status of electroweak theory on eve experimentation at CERN's Large Hadron Collider (LHC). A compact summary logic and structure precedes an examination what experimental tests ... Read More
Gaseous biofuels have emerged as a substitute for fossil fuels in the current scenario of energy requirement. These low sulphur and nitrogen content. Because carbon-neutral qualities, they possess lower pollution tendency compared to fuels. Hence it is essential characterize biomasses identify their potential suitability small-scale power generation using gasifiers. In this study, five readily available namely, wood chips, coconut shells, cotton stalk, paddy straw, banana leaves been...
We study the skyrmion structure in Cu2OSeO3 using resonant x-ray spectroscopy. The shows long range fluctuations of ferrimagnetic ordering, and above-gap optical excitation reduces magnetic ordering on a 40 picosecond timescale.