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Item Synthesis, phase confirmation and electrical properties of (1 ? x)KNNS?xBNZSH lead-free ceramics(Springer, 2022-02-02T00:00:00) Kumar, Amit; Kumari, Sapna; Kumar, V.; Kumar, Prashant; Thakur, Vikas N.; Kumar, Ashok; Goyal, P.K.; Arya, Anil; Sharma, A.L.In the present work, lead-free piezoelectric ceramics (Rx)(K0.5Na0.5)(Nb0.96Sb0.04O3)?x(Bi0.5Na0.5)(Zr0.8Sn0.1Hf0.1)O3 [abb. as (Rx)KNNS?xBNZSH, 0 ? x ? 0.04] were prepared via solid-state sintering technique. The thermal behavior of mixed powders has been investigated for x = 0, 0.02, and 0.04 using TGA-DSC analysis to estimate the calcination temperature. The structural, morphological, dielectric, ferroelectric and piezoelectric properties are analyzed through the appropriate characterization techniques. The X-ray diffraction (XRD) patterns demonstrate a pure perovskite phase structure for all the sintered samples. Further, the coexistence of rhombohedral to orthorhombic (R-O) phase is observed in ceramic sample with x = 0.02. The morphology of all the sintered samples exhibits an inhomogeneous, dense microstructure with the rectangular grain, while for x = 0.02, a relatively homogeneous distribution of grains is observed. BNZSH doping decreases the average grain size from 2.22 to 0.33�?m for x = 0 to x = 0.04, respectively. Owing to the presence of multiple-phase coexistence as well as the improved microstructure and enhanced dielectric properties (dielectric constant ?r = 1080, ?max = 5301; Curie temperature - TC ~ 317��C; dielectric loss - tan? ~ 6%) the ceramics with x = 0.02 has been found to have a large piezoelectric coefficient (d33) of ~180 pC/N, remnant polarization (Pr) ~ 16.7 �C/cm2 and coercive field (Ec) ~ 10.7�kV/cm. We believe it will expand the range of applications for KNN-based ceramics. � 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Item Growth, characterizations, and the structural elucidation of diethyl-2-(3-oxoiso-1,3-dihydrobenzofuran-1-ylidene)malonate crystalline specimen for dielectric and electronic filters, thermal, optical, mechanical, and biomedical applications using conventional experimental and theoretical practices(Springer, 2021-08-18T00:00:00) Rajkumar, M.; Maalmarugan, J.; Flora, G.; Surendarnath, S.; Christy, S.; Periyathambi, P.; Kumar, Shashank; Patel, R.P.; Lobo, F. Dayana; Singh, Atul Kumar; Vimalan, M.; SenthilKannan, K.The single crystals of diethyl-2-(3-oxoiso-1,3-dihydrobenzofuran-1-ylidene) malonate (D23DYM) were grown successfully and efficiently by the standard slow evaporation method. The lattice cell parameters by XRD analysis also confirmed that the crystal system is Triclinic with the space group of P?. The FTIR spectrum portrays the presence of major and active functional groups in D23DYM. The thermal studies explained the two major weight losses between 107 and 153��C and 153 and 800��C for D23DYM have been observed. It is very clear that the hardness profile of D23DYM increases with increase in load which confirms reverse indentation size effect (RISE), and the work-hardening coefficient 'n' was observed as 2.936. The negative photoconductive nature as the predominant property and the dielectric constant and dielectric loss are perfectly and accurately measured and properly reported. The structural properties by theoretical manner confirm the elucidation as well as the confirmation for XRD data and the computational way of identifying the lattice bond length and bond angles using software. Diabetes mellitus is the commonly occurring disease associated with lifestyle and feeding behavior of D23DYM�organic crystals are tested by the use of molecular docking. The binding affinity values for the standard inhibitor A74DME and investigational compound D23DYM were ? 8.1�kJ/mole and ? 8.3�kJ/mole, respectively, and in future may get proceeded for in vivo animal analysis as well as anti-cancer work as the benzofuran is present in the crystal and is better diabetic- and cancer-opposing agent. � 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Item Zirconia nanoparticles/ferroelectric liquid crystal composites for ionic impurity-free memory applications(2013) Chandran, A.; Prakash, J.; Ganguly, P.; Biradar, A.M.We observed an ionic impurity-free memory effect using a zirconia nanoparticles (ZNPs)/ferroelectric liquid crystal (FLC) composite. The pure and ZNPs doped FLC cells have been analyzed by means of dielectric spectroscopy, polarizing optical microscopy and electrical resistance/conductivity measurements. The memory behavior in ZNPs/FLC composite was confirmed by dielectric dispersion, electrical, and optical studies, whereas dielectric loss spectra confirmed the disappearance of the low-frequency relaxation peak, which appears due to the presence of ionic impurities in FLC materials. The observed memory effect has been attributed to minimization of the depolarization field and ionic charges, whereas the reduction of ionic effects has been attributed to the strong adsorption of ionic impurities on the surface of ZNPs. The ZNPs dispersed in FLCs may play a role in trapping the impurity ions (minimize the depolarization fields) under applied voltage and cause a better memory effect in ZNPs doped FLC material. Moreover, the ion adsorption capability of ZNPs is found to be almost independent of temperature as the value of resistance did not change remarkably on increasing the temperature. The reduction of ionic impurities of FLCs by doping ZNPs did not show degradation over time, as we repeated the experiments on the same sample cells after many days and did not find ionic effects in the ZNPs doped FLC materials. These studies would be helpful to provide an idea for designing ionic impurity-free memory devices. ? 2013 The Royal Society of Chemistry.