Faculty Publications
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Item Colorimetric anion sensors based on positional effect of nitro group for recognition of biologically relevant anions in organic and aqueous medium, insight real-life application and DFT studies(Elsevier B.V., 2018) Singh, A.; Sahoo, S.K.; Trivedi, D.R.A new six colorimetric receptors A1-A6 were designed and synthesized, characterized by typical common spectroscopic techniques like FT-IR, UV–Visible, 1H NMR, 13C NMR and ESI-MS. The receptor A1 and A2 exhibit a significant naked-eye response towards F? and AcO? ions in DMSO. Due to presences of the NO2 group at para and ortho position with extended ?-conjugation of naphthyl group carrying –OH as a binding site. Compared to receptor A2, A1 is extremely capable of detecting F? and AcO? ions present in the form of sodium salts in an aqueous medium. This is owed to the occurrence of –NO2 group at para position induced in increasing the acidity of –OH proton. Consequently, it easily gets deprotonated in aqueous media. The detection limit of receptor A1 was turned out to be 0.40 and 0.35 ppm for F? and AcO? ions which is beneath WHO permission level (1.0 ppm). Receptor A1 shows a solitary property of solvatochromism in different aprotic solvents in presence of AcO? ion. Receptor A1 depicts high selectivity towards AcO? ion in DMSO: HEPES buffer (9:1, v/v). Receptor A1 proved itself for real life application by detecting anion in solution and solid state. The binding mechanism of receptor A1 with AcO? and F? ions was monitored from 1HNMR titration and DFT study. © 2017 Elsevier B.V.Item Hg 2+ induced hydrolysis of thiazole amine based Schiff base: Colorimetric and fluorogenic chemodosimeter for Hg 2+ ions in an aqueous medium(Elsevier B.V., 2019) Tekuri, V.; Sahoo, S.K.; Trivedi, D.Simple pyrene-based chemosensors 1 to 3, were synthesized from pyrene-1-carboxaldehyde and they were characterized using various spectroscopic techniques like UV–Vis, FT-IR, Mass, 1 H NMR and 13 C NMR. Among synthesized receptors, the receptor 1 shows high selectivity towards Hg 2+ ions. Further, the high selectivity of receptor 1 towards Hg 2+ ions in the presence of various other interfering metal ions like Ni 2+ , Zn 2+ , Mn 2+ , Co 2+ , Cu 2+ , Cr 3+ , Fe 3+ , Al 3+ , Ag + , Fe 2+ , Cd 2+ , Mg 2+ , Pb 2+ , Ca 2+ , Na + , K + was confirmed by UV–Vis and fluorescence methods. The detection limit for Hg 2+ ions was found to be 0.270 ?M. The chemodosimetric irreversible hydrolysis of the receptor 1 in the presence of Hg 2+ was studied by UV/Vis, fluorescence, FT-IR, LC-MS, 1 H NMR and theoretical DFT study. Further, the real life applications of receptor 1 for the determination of Hg 2+ ions were demonstrated by UV–Vis method. © 2019 Elsevier B.V.Item Generation of microholes on GFRP composite using ES-µ-ECDM system(Elsevier Ltd, 2022) Bhargav, K.V.J.; Shanthan, P.; Balaji, P.S.; Sahu, R.K.; Sahoo, S.K.Microfeatures fabrication on FRPs is very essential nowadays because of its growing demand in various industries like aerospace, automobile, space, marine, etc. Glass fiber reinforced plastic (GFRP) composite is one among the FRPs that has many potential applications with extraordinary physical, chemical and mechanical properties. Generation of microholes on GFRP composite has gained its pace in recent years because of its applications in circuit boards and filters in biomedical applications. This study focuses on the generation of microholes in GFRP composite using an in-house developed electrolyte-sonicated micro-electrochemical discharge machining (ES-µ-ECDM) system. The process parameters voltage (V), concentration (wt%), and feed rate (µm/s) are selected at three levels for performing experiments using FCC-RSM modeling. The machining responses material removal rate (MRR) and overcut (OC) are analyzed. A RSM-based regression model is developed, and a multi-objective optimization using the MOJAYA algorithm is employed to obtain a set of non-dominated Pareto optimal solutions. The Pareto optimal solution set showed a feed rate of 5 µm/s should be employed for better MRR and OC. The SEM micrographs have shown a feed rate of 5 µm/s produced smooth surfaces at voltages and concentrations less than 55 V and 17.5 wt%, respectively. © 2022 Elsevier LtdItem Establishing high temperature tribological performance and wear mechanism map of engineered in-situ TiB2 reinforced Mg-RE metal matrix composites(Elsevier Ltd, 2025) Sahoo, S.K.; Ramesh, M.R.; Panigrahi, S.K.The high temperature sliding wear behavior of microstructurally engineering in-situ sub-micron sized TiB2 reinforced ZE41 composite was studied and compared with it's base counterpart at varying loading conditions. The wear mechanism maps were constructed by correlating the microstructures of worn surfaces with different test parameters. The severe and catastrophic wear mechanisms like delamination and melt wear were wider in base and composite, while in the case of engineered composite, these zones are significantly narrow down. Due to the presence of thermally stable in-situ TiB2 particles and bimodal precipitates in engineered composite, the material showed sufficient resistance against wear induced deformation. Furthermore, the study established scientific knowhow on high-temperature wear induced deformation behavior by analyzing microstructural evolution in wear subsurface zone. © 2024