Examining the relationship between atmospheric pollutants and meteorological factors in Asansol city, West Bengal, India, using statistical modelling.

Meteorological conditions significantly impact ambient air quality in urban environments. This study focuses on Asansol, known as the "Coal City" and the "Industrial Heart of West Bengal," a notable hotspot for air pollution. Despite its significance, limited research has addressed the influence of meteorological factors on key air pollutants in this urban area. From January 2019 to December 2023, this investigation explores the relationships between meteorological parameters (including atmospheric temperature, relative humidity, rainfall, wind speed) and the concentrations of crucial air pollutants (PM2.5, PM10, NO2, SO2). Temporal trends in air pollutant concentrations are also analysed. The Spearman correlation method is used to establish associations between pollutant concentrations and meteorological variables, while multiple linear regression (MLR) models are employed to assess meteorological factors and potential impact on pollutant concentrations. The analysis reveals a decreasing trend in pollutant concentrations in Asansol. Temperature exhibits negative correlations with all pollutants in all seasons except for a positive correlation during the monsoon. Rainfall consistently displays significant negative correlations with pollutants in all seasons. Relative humidity is negatively correlated with pollutants in all seasons, and wind speed, except during the post-monsoon season, shows negative correlations with all pollutants. Linear models excel in predicting particulate matter concentrations but perform poorly in predicting gaseous contaminants. Accounting for seasonal fluctuations and meteorological parameters, this research enhances the accuracy of air pollution forecasting, contributing to a better understanding of air quality dynamics in Asansol and similar urban areas.

Mixed Stochastic-Deterministic Approach for Many-Body Perturbation Theory Calculations.

We present an approach for GW calculations of quasiparticle energies with quasiquadratic scaling by approximating high-energy contributions to the Green's function in its Lehmann representation with effective stochastic vectors. The method is easy to implement without altering the GW code, converges rapidly with stochastic parameters, and treats systems of various dimensionality and screening response. Our calculations on a 5.75° twisted MoS_{2} bilayer show how large-scale GW methods include geometry relaxations and electronic correlations on an equal basis in structurally nontrivial materials.

Electrochemistry-enabled residue-specific modification of peptides and proteins.

Selective chemical reactions at precise amino acid residues of peptides and proteins have become an exploding field of research in the last few decades. With the emerging utility of bioconjugated peptides and proteins as drug leads and therapeutic agents, the design of smart protocols to modulate and conjugate biomolecules has become necessary. During this modification, the most important concern of biochemists is to keep intact the structural integrity of the biomolecules. Hence, a soft and selective biocompatible reaction environment is necessary. Electrochemistry, a mild and elegant tunable reaction platform to synthesize complex molecules while avoiding harsh and toxic chemicals, can provide such a reaction condition. However, this strategy is yet to be fully exploited in the field of selective modification of polypeptides. With this possibility, the use of electrochemistry as a reaction toolbox in peptide and protein chemistry is flourishing day by day. Unfortunately, there is no suitable review article summarizing the residue-specific modification of biomolecules. The present review provides a comprehensive summary of the latest manifested electrochemical approaches for the modulation of five redox-active amino acid residues, namely cysteine, tyrosine, tryptophan, histidine and methionine, found in peptides and proteins. The article also highlights the incredible potential of electrochemistry for the regio- as well as chemoselective bioconjugation strategy of biomolecules.

Zinc oxide nano-flowers improve the growth and propagation of mulberry cuttings grown under different irrigation regimes by mitigating drought-related complications and enhancing zinc uptake.

Silkworm larvae mainly consume mulberry leaves; therefore, mulberry cultivation is important for the production of raw silk. Drought stress and micronutrient deficiency (Zn) are known to affect the propagation of mulberry cuttings. In this purview, the current investigation attempted to inspect the efficacy of different concentrations of zinc oxide nano-flower (ZnNFs) applied through both soil admixture and foliar spray on the propagation of mulberry cuttings grown under deficit irrigation regimes. The overall results demonstrated that the ZnNF-treated plant cuttings were well-adapted to drought stress and performed better in comparison to the control set. Out of the tested concentrations - ZnNF-10 (applied as 10 mg/kg soil and 10 ppm as foliar spray thrice) was found to be optimum, showing relatively better initial root establishment, the emergence of leaves, and survival and sprouting percentage. Further studies also confirmed an improvement in the accumulation of photosynthetic pigments, carbohydrates, and protein content even under extreme drought conditions. Most importantly, the ZnNF-10 treatment contributed to ROS detoxification and cell membrane protection by enhancing the pool of antioxidant enzymes. The study further demonstrated that ZnNF-10 application enhanced zinc content by 147.50%, 179.49%, and 171.99% in root, shoot, and leaves of the treated cuttings; thereby, improving the bioaccumulation factor of the plant parts. All of these interactive phenomena led to an increment in shoot height, biomass, leaf area, and leaf number of cuttings. These findings, therefore, indicated that ZnNFs can be developed as a promising nano-fertilizer for mulberry growth facilitating Zn uptake and mitigation of drought-induced complications.

Fe-Mn nanocomposites doped graphene quantum dots alleviate salt stress of Triticum aestivum through osmolyte accumulation and antioxidant defense.

An investigation was carried out to evaluate the effect of graphene quantum dots (GQD) and its nanocomposites on germination, growth, biochemical, histological, and major ROS detoxifying antioxidant enzyme activities involved in salinity stress tolerance of wheat. Seedlings were grown on nutrient-free sand and treatment solutions were applied through solid matrix priming and by foliar spray. Control seedlings under salinity stress exhibited a reduction in photosynthetic pigment, sugar content, growth, increased electrolyte leakage, and lipid peroxidation, whereas iron-manganese nanocomposites doped GQD (FM_GQD) treated seedlings were well adapted and performed better compared to control. Enzymatic antioxidants like catalase, peroxidase, glutathione reductase and NADPH oxidase were noted to increase by 40.5, 103.2, 130.19, and 141.23% respectively by application of FM_GQD. Histological evidence confirmed a lower extent of lipid peroxidation and safeguarding the plasma membrane integrity through osmolyte accumulation and redox homeostasis. All of these interactive phenomena lead to an increment in wheat seedling growth by 28.06% through FM_GQD application. These findings highlight that micronutrient like iron, manganese doped GQD can be a promising nano-fertilizer for plant growth and this article will serve as a reference as it is the very first report regarding the ameliorative role of GQD in salt stress mitigation.

Molecular dissection of cellular response of pancreatic islet cells to Bisphenol-A (BPA): A comprehensive review.

Bisphenol A (BPA) is an endocrine disrupting chemical which poses great concern because of its high proportionate industrial production, omnipresent human exposure and budding toxic consequences in human. A plethora of previous studies has connected BPA to a variety of negative health outcomes and diabetes mellitus is among the first bencher. However, there is disagreement over the degree of toxic effects generated by low and high doses of BPA and critical period of exposure. Furthermore, the safe level of BPA determined by classical toxicological studies does not protect pancreatic islet cells from low dose effects of BPA. Thus, the extremities of toxic effects on pancreatic islets associated with BPA exposure are complicated and contentious. In this review, we highlighted different cellular and molecular pathways targeted by BPA to mediate its action on pancreatic islets with consideration of both low and high dose effects. Besides estrogen receptor α and ß, BPA also uses non canonical membrane bound estrogen receptor and G-protein coupled estrogen receptor to confer its toxic effects. In doing so, BPA modulates ion channels, and transcription factors; causes aggregation of human islet amyloid polypeptide, endoplasmic reticulum and mitochondrial stress; and results in activation of NFκB in pancreatic ß cells. BPA also renders a major shift in ß to α cell ratio in islets causing deregulated glucagon secretion. Hence, understanding of various mechanisms of BPA action on the pancreatic islets will provide meaningful insights in recognizing the risk posed by exposure to low and high doses of BPA.

Dichlorophene activates aryl hydrocarbon receptor (AhR) and indoleamine 2, 3-dioxygenase 1 (IDO1) to mediate splenotoxicity in rat.

Dichlorophene (DCP) is a halogenated phenolic compound, widely used as fungicide, bactericide and antiprotozoan and also exhibit therapeutic application in several pathological conditions. Taking account of broad use of DCP, its possible effect on spleen (an important immune organ) was investigated in this study. Male albino rats were treated with graded doses of DCP (10%, 20% and 30% of LD50) and spleen and blood were obtained at 24, 48 and 72 hours post treatment. Oxidative stress parameters, proinflammatory cytokines and protein expression of aryl hydrocarbon receptor (AhR), indoleamine-2, 3-Dioxygenase 1 (IDO1) and nuclear factor erythroid 2-related factor 2 (Nrf2) were measured along with histopathological evaluation of spleen. In the present study, DCP perturbs redox status of splenocytes of rats as evidenced by excess ROS generation, lipid peroxidation and nitric oxide production simultaneously with reduction of antioxidant level [glutathione (GSH)] and inhibition of antioxidative enzymes [superoxide dismutase (SOD) and catalase (CAT)]. Two important proinflammatory cytokines, IL-6 and TNF-α were found to be elevated upon DCP treatment. Moreover, DCP also caused activation of AhR and IDO1 with simultaneous down regulation of Nrf2. All these effects of DCP were found to be dose and duration dependent. DCP also affects the spleen micro-architecture in the present study and these alterations were more prominent in high dose group at 72 hours post treatment. Taken together, all these results suggested that DCP induces oxidative stress and also increases proinflammatory cytokine levels to mount its toxic effect on spleen.

Population analysis with Wannier orbitals.

We formulate Wannier orbital overlap population and Wannier orbital Hamilton population to describe the contribution of different orbitals to electron distribution and their interactions. These methods, which are analogous to the well-known crystal orbital overlap population and crystal orbital Hamilton population, provide insight into the distribution of electrons at various atom centers and their contributions to bonding. We apply this formalism in the context of a plane-wave density functional theory calculation. This method provides a means to connect the non-local plane-wave basis to a localized basis by projecting the wave functions from a plane-wave density functional theory calculation to a localized Wannier orbital basis. The main advantage of this formulation is that the spilling factor is strictly zero for insulators and can systematically be made small for metals. We use our proposed method to study and obtain bonding and electron localization insights in five different materials.

Correction: Strongly coupled Mn3O4-porous organic polymer hybrid: a robust, durable and potential nanocatalyst for alcohol oxidation reactions.

[This corrects the article DOI: 10.1039/C6RA07200C.].

Nanofibrils of a CuII-Thiophenyltriazine-Based Porous Polymer: A Diverse Heterogeneous Nanocatalyst.

Herein, we report knitting of a thiophenyltriazine-based porous organic polymer (TTPOP) with high surface area and high abundance of nitrogen and sulfur sites, synthesized through a simple one-step Friedel-Crafts reaction of 2,4,6-tri(thiophen-2-yl)-1,3,5-triazine and formaldehyde dimethyl acetal in the presence of anhydrous FeCl3, and thereafter grafting of Cu(OAc)2·H2O in the porous polymer framework to achieve the potential catalyst (CuII-TTPOP). TTPOP and CuII-TTPOP were characterized thoroughly utilizing solid-state 13C-CP MAS NMR, Fourier transform infrared, wide-angle powder X-ray diffraction, thermogravimetric analysis, and X-ray photoelectron spectroscopy and surface imaging by transmission electron microscopy and field emission scanning electron microscopy. The porosity of the nanomaterials was observed in the surface imaging and verified through conducting N2 gas adsorption techniques. Keeping in mind the tremendous importance of C-C and C-N coupling and cyclization processes, the newly synthesized CuII-TTPOP was employed successfully for a wide range of organic catalytic transformations under mild conditions to afford directly valuable diindolylmethanes and spiro-analogues, phthalimidines, propargyl amines, and their sugar-based chiral compounds with high yields using readily available substrates. The highly stable new heterogeneous catalyst showed outstanding sustainability, robustness, simple separation, and recyclability.

Role of Surface Phenolic-OH Groups in N-Rich Porous Organic Polymers for Enhancing the CO2 Uptake and CO2/N2 Selectivity: Experimental and Computational Studies.

Design and successful synthesis of phenolic-OH and amine-functionalized porous organic polymers as adsorbent for postcombustion CO2 uptake from flue gas mixtures along with high CO2/N2 selectivity is a very demanding research area in the context of developing a suitable adsorbent to mitigate greenhouse gases. Herein, we report three triazine-based porous organic polymers TrzPOP-1, -2, and -3 through the polycondensation of two triazine rings containing tetraamine and three dialdehydes. These porous organic polymers possess high Brunauer-Emmett-Teller (BET) surface areas of 995, 868, and 772 m2 g-1, respectively. Out of the three materials, TrzPOP-2 and TrzPOP-3 contain additional phenolic-OH groups along with triazine moiety and secondary amine linkages. At 273 K, TrzPOP-1, -2, and -3 displayed CO2 uptake capacities of 6.19, 7.51, and 8.54 mmol g-1, respectively, up to 1 bar pressure, which are considerably high among all porous polymers reported till date. Despite the lower BET surface area, TrzPOP-2 and TrzPOP-3 containing phenolic-OH groups showed higher CO2 uptakes. To understand the CO2 adsorption mechanism, we have further performed the quantum chemical studies to analyze noncovalent interactions between CO2 molecules and different polar functionalities present in these porous polymers. TrzPOP-1, -2, and -3 have the capability of selective CO2 uptake over that of N2 at 273 K with the selectivity of 61:1, 117:1, and 142:1 by using the initial slope comparing method, along with 108.4, 140.6, and 167.4 by using ideal adsorbed solution theory (IAST) method, respectively. On the other hand, at 298 K, the calculated CO2/N2 selectivities in the initial slope comparing method for TrzPOP-1, -2, and -3 are 27:1, 72:1, and 96:1, whereas those using IAST method are 42.1, 75.7, and 94.5, respectively. Cost effective and scalable synthesis of these porous polymeric materials reported herein for selective CO2 capture has a very promising future for environmental clean-up.

A facile approach for the synthesis of hydroxyl-rich microporous organic networks for efficient CO2 capture and H2 storage.

A new series of porous organic networks (PONs) internally decorated with several free -OH functional groups has been synthesized through acid catalyzed condensation reaction of terephthalaldehyde and nucleophilic aromatic compounds. These materials possess high Brunauer-Emmett-Teller specific surface areas (592-865 m2 g-1) and showed maximum CO2 adsorption capacity of 4.31 mmol g-1 and H2 uptake of 8.23 mmol g-1 at 273 and 77 K, respectively, under 1 bar.

MnFe2 O4 Nanocrystals Wrapped in a Porous Organic Polymer: A Designed Architecture for Water-Splitting Photocatalysis.

A novel MnFe2 O4 -porous organic polymer (POP) nanocomposite was synthesized by a facile hydrothermal method and using the highly cross-linked N-rich benzene-benzylamine POP. The nanocomposite presented highly efficient photocatalytic performance in the hydrogen evolution reaction (HER) from pure water without addition of any sacrificial agent under one AM 1.5 G sunlight illumination. A photocatalytic activity of 6.12 mmol h-1 g-1 was achieved in the absence of any noble metal cocatalyst, which is the highest H2 production rate reported for nonprecious metal catalysts. The photocatalytic performance of MnFe2 O4 -POP could be attributed to the intrinsic synergistic effects of manganese ferrite (MnFe2 O4 ) nanoclusters interacting with the nitrogen dopant POP with a unique mesoporous nanoarchitecture and spatially confined growth of MnFe2 O4 in the interconnected POP network, leading to high visible-light absorption with fast electron transport.

Silver nanoparticles embedded over porous metal organic frameworks for carbon dioxide fixation via carboxylation of terminal alkynes at ambient pressure.

Ag nanoparticles (NPs) has been supported over a porous Co(II)-salicylate metal-organic framework to yield a new nanocatalyst AgNPs/Co-MOF and it has been thoroughly characterized by powder X-ray diffraction (XRD), thermogravimetric analysis (TGA), energy dispersive X-ray spectrometry (EDX), high-resolution transmission electron microscopy (HR-TEM), UV-vis diffuse reflection spectroscopy (DRS) and N2 adsorption/desorption analysis. The AgNPs/Co-MOF material showed high catalytic activity in the carboxylation of terminal alkynes via CO2 fixation reaction to yield alkynyl carboxylic acids under very mild conditions. Due to the presence of highly reactive AgNPs bound at the porous MOF framework the reaction proceeded smoothly at 1atm CO2 pressure. Moreover, the catalyst is very convenient to handle and it can be reused for several reaction cycles without appreciable loss of catalytic activity in this CO2 fixation reaction, which suggested a promising future of AgNPs/Co-MOF nanocatalyst.

Mesoporous polyacrylic acid supported silver nanoparticles as an efficient catalyst for reductive coupling of nitrobenzenes and alcohols using glycerol as hydrogen source.

Silver nanoparticle immobilized mesoporous cross-linked polyacrylic acid (Ag-MCP-1) has been synthesized via aqueous-phase polymerization of acrylic acid followed by the surface immobilization with silver nanoparticles. The nanocomposite material has been characterized by different spectroscopic techniques. Powder X-ray diffraction patterns revealed the formation of silver nanoparticles, while transmission electron microscope image showed that Ag nanoparticles are formed and uniformly dispersed in the mesoporous polyacrylic acid. The Ag-MCP-1 nanocomposite can be used as an efficient heterogeneous catalyst in the reductive coupling of nitrobenzenes and alcohols using glycerol as hydrogen source. This nanocomposite can be reused more than five times without any significant decrease in its catalytic activity.

Ag@polypyrrole: A highly efficient nanocatalyst for the N-alkylation of amines using alcohols.

We have synthesized Ag@polypyrrole nanomaterial by dispersing ultrafine silver nanoparticles (Ag NPs) over the organic polymer polypyrrole. The Ag@polypyrrole material has been characterized by powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), Fourier transform infrared (FT-IR), ultraviolet-visible absorption (UV-vis) and atomic adsorption spectroscopy (AAS), and thermogravimetric analysis (TGA). The XRD pattern suggested the cubic crystalline phase of Ag NPs in Ag@polypyrrole. TEM image analysis revealed that silver nanoparticles are highly dispersed in the polymer matrix. The Ag@polypyrrole acts as an efficient and versatile heterogeneous nanocatalyst in the N-alkylation of amines using alcohols. The catalyst can be easily prepared, highly robust and reused several times without decrease in its catalytic activity.

Morphology evolution of single-crystalline hematite nanocrystals: magnetically recoverable nanocatalysts for enhanced facet-driven photoredox activity.

We have developed a new green chemical approach for the shape-controlled synthesis of single-crystalline hematite nanocrystals in aqueous medium. FESEM, HRTEM and SAED techniques were used to determine the morphology and crystallographic orientations of each nanocrystal and its exposed facets. PXRD and HRTEM techniques revealed that the nanocrystals are single crystalline in nature; twins and stacking faults were not detected in these nanocrystals. The structural, vibrational, and electronic spectra of these nanocrystals were highly dependent on their shape. Different shaped hematite nanocrystals with distinct crystallographic planes have been synthesized under similar reaction conditions, which can be desired as a model for the purpose of properties comparison with the nanocrystals prepared under different reaction conditions. Here we investigated the photocatalytic performance of these different shaped-nanocrystals for methyl orange degradation in the presence of white light (λ > 420 nm). In this study, we found that the density of surface Fe(3+) ions in particular facets was the key factor for the photocatalytic activity and was higher on the bitruncated-dodecahedron shape nanocrystals by coexposed {104}, {100} and {001} facets, attributing to higher catalytic activity. The catalytic activity of different exposed facet nanocrystals were as follows: {104} + {100} + {001} (bitruncated-dodecahedron) > {101} + {001} (bitruncated-octahedron) > {001} + {110} (nanorods) > {012} (nanocuboid) which provided the direct evidence of exposed facet-driven photocatalytic activity. The nanocrystals were easily recoverable using an external magnet and reused at least six times without significant loss of its catalytic activity.

Fabrication of Ruthenium Nanoparticles in Porous Organic Polymers: Towards Advanced Heterogeneous Catalytic Nanoreactors.

A novel strategy has been adopted for the construction of a copolymer of benzene-benzylamine-1 (BBA-1), which is a porous organic polymer (POP) with a high BET surface area, through Friedel-Crafts alkylation of benzylamine and benzene by using formaldehyde dimethyl acetal as a cross-linker and anhydrous FeCl3 as a promoter. Ruthenium nanoparticles (Ru NPs) were successfully distributed in the interior cavities of polymers through NaBH4, ethylene glycol, and hydrothermal reduction routes, which delivered Ru-A, Ru-B, and Ru-C materials, respectively, and avoided aggregation of metal NPs. Homogeneous dispersion, the nanoconfinement effect of the polymer, and the oxidation state of Ru NPs were verified by employing TEM, energy-dispersive X-ray spectroscopy mapping, cross polarization magic-angle spinning (13)C NMR spectroscopy, and X-ray photoelectron spectroscopy analytical tools. These three new Ru-based POP materials exhibited excellent catalytic performance in the hydrogenation of nitroarenes at RT (with a reaction time of only ≈ 30 min), with high conversion, selectivity, stability, and recyclability for several catalytic cycles, compared with other traditional materials, such as Ru@C, Ru@SiO2, and Ru@TiO2, but no clear agglomeration or loss of catalytic activity was observed. The high catalytic performance of the ruthenium-based POP materials is due to the synergetic effect of nanoconfinement and electron donation offered by the 3D POP network. DFT calculations showed that hydrogenation of nitrobenzene over the Ru (0001) catalyst surface through a direct reaction pathway is more favorable than that through an indirect reaction pathway.

A ruthenium-grafted triazine functionalized mesoporous polymer: a highly efficient and multifunctional catalyst for transfer hydrogenation and the Suzuki-Miyaura cross-coupling reactions.

A new ruthenium-grafted mesoporous organic polymer Ru-MPTAT-1 has been synthesized via simple and facile in situ radical polymerization of 2,4,6-triallyloxy-1,3,5-triazine (TAT) in aqueous medium in the presence of an anionic surfactant (sodium dodecyl sulfate) as a template, followed by grafting of Ru(II) onto its surface. Ru-MPTAT-1 has been characterized by elemental analysis, powder XRD, HRTEM, FT-IR, UV-vis DRS, TG-DTA, FESEM and XPS characterization tools. The Ru-MPTAT-1 material showed very good catalytic activity in the Suzuki-Miyaura cross-coupling reaction for aryl halides and transfer hydrogenation reaction for a series of carbonyl compounds. The catalyst is easily recoverable from the reaction mixture and can be reused several times without appreciable loss of catalytic activity in the above reactions. Highly dispersed and strongly bound Ru(II) sites at the mesoporous polymer surface could be responsible for the observed high activity of the Ru-MPTAT-1 catalyst in these reactions.

Tungstic acid functionalized mesoporous SBA-15: a novel heterogeneous catalyst for facile one-pot synthesis of 2-amino-4H-chromenes in aqueous medium.

A new highly ordered mesoporous tungstic acid functionalized SBA-15, TAFMC-1 has been synthesized via post-synthesis modification of mesoporous SBA-15 with (3-chloropropyl) triethoxysilane followed by substitution reaction of chlorine atom of the 3-chloropropyl group by tungstic acid group under refluxing conditions in n-hexane. The tungstic acid functionalized mesoporous silica material has been characterized by using small angle powder X-ray diffraction, N2 sorption, HR-TEM, FE-SEM, FT-IR and solid state MAS NMR studies. TAFMC-1 catalyzes the facile one-pot catalytic three-component condensation reaction of resorcinol, aromatic aldehyde and malononitrile for the synthesis of a diverse range of 2-amino-4H-chromenes in aqueous medium. This heterogeneous catalyst can be recycled very efficiently for six consecutive reaction cycles without significant loss of catalytic activity.