A Pd (II)-catalyzed direct C3-(sp)-H alkenylation of heteroarenes using benzothiazole as a directing group was successfully achieved. A wide range of 2--alkylpyrroles undergo an oxidative coupling with a variety of acrylates to furnish highly regio- and chemoselective E-alkenylation products at the C3 position. An important intermediate complex has been isolated and characterized so as to have an insight into the mechanism.
View Article and Find Full Text PDFIn this study, we investigated the aggregation-induced delayed fluorescence (AIDF) properties of three luminogens - TN, TA, and TP. Our comprehensive theoretical analysis reveals a significant reduction in the Δ in their aggregated or solid-state, activating TADF, on a ∼μs time-scale. Additionally, these luminogens demonstrate two-photon excited anti-Stokes photoluminescence emission and improved photocurrent generation, attributed to their strong charge transfer characteristics and longer singlet exciton lifetimes.
View Article and Find Full Text PDFThe present study is an attempt to understand the level of PM pollution and its toxicity based on the oxidative potential (OP) during the winter-time pollution period over Kolkata, a megacity at the eastern most parts of Indo-Gangetic Plain (IGP) during the period of 2016-2023. We have assessed the effectiveness of the Government of India's national mission, the National Clean Air Program (NCAP) in PM reduction over this city, and the study revealed that the mission has been efficacious in lessening the PM load by 28 % from pre-NCAP (2016-2019) to post-NCAP (2021-2023) periods. Several policy interventions reduced the contributions from various anthropogenic sources; however, biomass/solid waste burning remained a major concern with no significant reduction.
View Article and Find Full Text PDFPathological activation of the Nod-like receptor family pyrin domain containing protein 3 (NLRP3) inflammasome signaling underlies many autoimmune and neuroinflammatory conditions. Here we report that, a rationally designed, novel, orally active, selective NLRP3 inflammasome inhibitor, Usnoflast (ZYIL1), showed potent inhibition of ATP, Nigericin and monosodium urate-mediated interleukin (IL)-1β release in THP-1 cells and human PBMC. In isolated microglia cells, the IC of ZYIL1 mediated inhibition of IL-1β was 43 nM.
View Article and Find Full Text PDFCrystalline materials exhibiting non-centrosymmetry and possessing substantial surface dipole moments play a critical role in piezoelectricity. Designing biocompatible self-assembled materials with these attributes is particularly challenging when compared to inorganic materials and ceramics. In this study, we elucidate the crystal conformations of novel cyclic peptides that exhibit self-assembly into tubular structures characterized by unidirectional hydrogen bonding and piezoelectric properties.
View Article and Find Full Text PDFThis work reports that ligand engineering can modulate the triplet harvesting mechanism in iodide-bridged rhombic CuI complexes. Complex-1, with a smaller Cu-Cu distance, exhibits phosphorescence from (M+X)LCT and CC states with 66% quantum yield, whereas an increased Cu-Cu distance in complex-2 results in a switch of the emission from phosphorescence to TADF, which occurs via (M+X)LCT states with 83% quantum yield. The TADF property of complex-2 has been utilized for the fabrication of a pc-LED emitting efficient warm white light.
View Article and Find Full Text PDFAdsorbed molecules on a catalyst almost always arrange themselves in a manner that is far from perfectly random, which gives rise to spatial correlations. These correlations are a result of the interactions between the adsorbed species (adspecies) as well as elementary processes such as diffusion and reaction events that shape the adspecies arrangements. Despite their importance, spatial correlations are usually ignored while writing species balance equations for the modeling of heterogeneous catalytic systems.
View Article and Find Full Text PDFIn multicomponent lattice problems, for example, in alloys and at crystalline surfaces and interfaces, atomic arrangements exhibit spatial correlations that dictate the kinetic and thermodynamic phase behavior. These correlations emerge from interparticle interactions and are frequently reported in terms of the short-range order (SRO) parameter. Expressed usually in terms of pair distributions and other cluster probabilities, the SRO parameter gives the likelihood of finding atoms/molecules of a particular type in the vicinity of other atoms.
View Article and Find Full Text PDFTo investigate the intrinsic relation between carbonic anhydrase inhibition and anticancer activity, we have prepared four sets of diaryl urea molecules and tested for the inhibition of hCA-IX and XII on two breast cancer cell lines. Among 21 compounds, compound J2 (with -SONH group) and J16 (without -SONH group) showed the best activity under normoxic and hypoxic conditions. The IC values of J16 for MDA-MB-231 and MCF-7 cells, under normoxic condition were 6.
View Article and Find Full Text PDFThis study attempts to examine the morphological, elemental and physical characteristics of PM over the Indian Himalayan Region (IHR) using FTIR and scanning electron microscopy-energy dispersive X-ray (SEM-EDX) analysis. The study aimed at source identification of PM by exploring the inorganic ions, organic functional groups, morphology and elemental characteristics. The pollution load of PM was estimated as 63 ± 22 μg m; 53 ± 16 μg m; 67 ± 26 μg m and 55 ± 11 μg m over Mohal-Kullu, Almora, Nainital and Darjeeling, respectively.
View Article and Find Full Text PDFTo investigate the acidity and the water-soluble oxidative potential of PM, during the continental biomass-burning plume transport, a three-year (2018-2020) winter-time campaign was conducted over a pristine island (21.35°N, 88.32°E) of Sundarban mangrove ecosystem situated at the shore of Bay of Bengal.
View Article and Find Full Text PDFProteins under physiological conditions are inherently mobile and sample a vast array of structures. Consequently, the need arises, on the one hand, at a local level to determine the independent moving parts and their associated conformations and kinetics, and on the other hand, at a global level, to quantify the disorder in the full protein molecule. We present an approach that provides these quantities in the form of local kinetic network models, which are constructed by analyzing the molecular dynamics (MD) trajectories of the protein molecule.
View Article and Find Full Text PDFThis research article explores the distinct TADF efficiency of three donor-acceptor based regio-isomers: DPAOCN (-isomer), DPAMCN (-isomer), and DPAPCN (-isomer). DPAPCN exhibits maximum TADF efficiency in both solution and solid-state with an impressive reverse inter-system crossing (RISC) rate of ∼10 s; the underlying cause being the minimum singlet-triplet splitting energy or Δ and maximum SOC (spin-orbit coupling) between the S & T states. Apart from TADF, differences in crystal packing of the regio-isomers result in intriguing bulk phase properties.
View Article and Find Full Text PDFA straightforward and practical method has been developed to access α-substituted glutaric diesters from acrylates and aldehydes using visible light, with Eosin Y facilitating hydrogen atom transfer (HAT) and subsequent Giese-type addition. Also, sunlight has been successfully used as an alternative sustainable light source. The method has also been explored to access substituted 4,5-dihydro-2H-pyridazinones, which have potential biological and industrial applications.
View Article and Find Full Text PDFLattice simulations are an important class of problems in crystalline solids, surface science, alloys, adsorption, absorption, separation, catalysis, to name a few. We describe a fast computational method for performing lattice thermodynamic calculations that is based on the use of the reverse Monte Carlo (RMC) technique and multiple short-range order (SRO) parameters. The approach is comparable in accuracy to the Metropolis Monte Carlo (MC) method.
View Article and Find Full Text PDFA year-long study (January-December 2019) on the chemical characterization and meteorological impact on PM was conducted over a semi-urban station, Shyamnagar, in the easternmost part of the Indo-Gangetic Plains (IGP). PM concentrations (Mean = 81.69 ± 66.
View Article and Find Full Text PDFHematohidrosis is an uncommon pathophysiological condition of sweating blood. A young lady with abrupt bleeding from the skin (since January 2017) was brought to the emergency. The bleeding was vanished after mopping with no site of injury, but it reappeared soon enough confirming its nature.
View Article and Find Full Text PDFSecond-generation bioenergy, a carbon neutral or negative renewable resource, is crucial to achieving India's net-zero emission targets. Crop residues are being targeted as a bioenergy resource as they are otherwise burned on-field, leading to significant pollutant emissions. But estimating their bioenergy potential is problematic because of broad assumptions about their surplus fractions.
View Article and Find Full Text PDFAlkaline leachate, dust generation, and foul smell during the stacking process of natural rubber biosludge (NRBS) can pollute surrounding water, soil, and air. In this study, natural rubber chemically activated carbon (NRCAC) has been synthesized for the first time from NRBS by pyrolysis using ZnCl at 700 °C for adsorptive removal of Cr(VI) and methylene blue (MB) from aqueous solutions. Both NRBS and NRCAC were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), Brunauer-Emmett-Teller (BET), and thermogravimetric analyzer (TGA).
View Article and Find Full Text PDFWe present a probabilistic microkinetic modeling (MKM) framework that incorporates the short-ranged order (SRO) evolution for adsorbed species (adspecies) on a catalyst surface. The resulting model consists of a system of ordinary differential equations. Adsorbate-adsorbate interactions, surface diffusion, adsorption, desorption, and catalytic reaction processes are included.
View Article and Find Full Text PDFDue to ultrabright and stable blue light emission, GaN has emerged as one of the most famous semiconductors of the modern era, useful for light-emitting diodes, power electronics, and optoelectronic applications. Extending GaN's optical resonance from visible to mid- and-far-infrared spectral ranges will enable novel applications in many emerging technologies. Here we show hexagonal honeycomb-shaped GaN nanowall networks and vertically standing nanorods exhibiting morphology-dependent Reststrahlen band and plasmon polaritons that could be harnessed for infrared nanophotonics.
View Article and Find Full Text PDFRange anxiety is a primary concern among present-day electric vehicle (EV) owners, which could be curtailed by maximizing the driving range per charge or reducing the charging time of the lithium-ion battery (LIB) pack. Maximizing the driving range is a multifaceted task as charging-discharging the LIB up to 100% of its nominal capacity is limited by the cell chemistry (voltage window) and cell operating conditions. Our studies on commercial LiFePO/graphite cells show that a cycle life of 4320 is achieved at 4C rate with 80% SOC-100% DOD combination (12 min charging time), which is the highest among the works reported with this cell chemistry.
View Article and Find Full Text PDFA year-long (March 2019-February 2020) study on the characterization of fine mode carbonaceous aerosols has been conducted over a high altitude urban atmosphere, Darjeeling (27.01°N, 88.15°E, 2200 m asl) in eastern Himalaya.
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