Review on Carbon Dioxide Utilization for Cycloaddition of Epoxides by Ionic Liquid-Modified Hybrid Catalysts: Effect of Influential Parameters and Mechanisms Insight

The storage, utilization, and control of the greenhouse (CO2) gas is a topic of interest for researchers in academia and society. The present review article is dedicating to cover the overall role of ionic liquid-modified hybrid materials in cycloaddition reactions. Special emphasis is on the synthesis of various cyclic carbonate using ionic liquid-based modified catalysts. Catalytic activity studies have discussed with respect to process conditions and their effects on conversion and product selectivity for the reaction of cycloaddition of CO2 with styrene oxide. The reaction temperature and the partial pressure of CO2 have found to play a key role in cyclic carbonate formation. The role of other influential parameter (solvent effect) is also discussed for the conversion of cyclic/aromatic oxides to polycarbonate production. Our own research work that deals with ionic liquid-based halide-modified mesoporous catalyst (MCM-41 type) derived from rice husk waste has also been discussed. Finally, the role of carbon dioxide activation and ring-opening mechanisms involved in the cyclic carbonate product formation from CO2 have been discussed

Review on Carbon Nanotube Varieties for Healthcare Application: Effect of Preparation Methods and Mechanism Insight

Many potential uses of carbon nanotubes (CNT) in various sectors have created an urge to assess their diverse range of properties pertaining to various applications like catalysis, biosensor, and antimicrobial activity. Increasing studies on the biosensor and antibacterial activity of CNT have prompted tremendous interest in the utilization of the carbon-based nanostructured material as an alternative to currently existing antibiotics. However, the study of bactericidal aspects of this nanomaterial is relatively new and hence the deeper understanding of the various physicochemical characteristics and antimicrobial nature of CNT is extremely wanted. This review covers the effect of framework substitution and explains the understanding of membrane disintegration and oxidative stresses upon nanomaterials for antimicrobial activity. The present article has also reviewed effect of preparation nanoparticle deposition and framework modification on carbon nanotube structure. The recent research on graphene-modified nanomaterials for biosensor applications related to healthcare/clinical applications have also been discussed. Major physicochemical contributing factors such as size, functionalization, high surface area, and aggregation features of CNT assisting in the bacterial killing have nicely been outlined. Hence, the present review explains the supporting information related with Single and multi-walled carbon nanotube and summarized the advantages of functionalized carbon nanotube/graphene-based nanostructured carbon-based materials towards protection and reduction of bacterial/viral infections in the healthcare sector

Synthesis of New Hybrid Structured Magnetite Crosslinked Poly Ionic Liquid for Efficient Removal of Coomassie Brilliant Blue R-250 Dye in Aqueous Medium

In this work, new crosslinked pyridinium poly ionic liquid and its magnetite hybrid structured composite were prepared and applied to remove the toxic dye Coomassie Brilliant Blue (CBB-R250) from aqueous solutions. In this respect, vinyl pyridine, maleic anhydride, and dibromo nonane were used to prepare crosslinked quaternized vinyl pyridinium/maleic anhydride ionic liquid (CQVP-MA). Furthermore, a linear copolymer was prepared by the reaction of vinyl pyridine with bromo nonane followed by its copolymerization with maleic anhydride in order to use it as a capping agent for magnetite nanoparticles. The monodisperse MNPs were incorporated into the crosslinked PIL (CQVP-MA) by ultrasonication to prepare CQVP-MA/Fe3O4 composite to facilitate its recovery using an external magnetic field and enhance its adsorption capacity. The chemical structures, thermal stabilities, zeta potential, particle size, EDS, and SEM of the prepared CQVP-MA and CQVP-MA/Fe3O4 were investigated. Adsorption kinetics, isotherms, and mechanisms of CB-R250 elimination from aqueous solutions using CQVP-MA and CQVP-MA/Fe3O4 were also studied, and the results revealed that the pseudo second-order kinetic model and the Langmuir isotherm model were the most suitable to describe the CBB adsorption from an aqueous solution. The adsorption capacities of CQVP-MA and CQVP-MA/Fe3O4 were found to be 1040 and 1198, respectively, which are more than those for previously reported material in the literature with reasonable stability for five cycles

Rapid Multi-Residue Method for Simultaneous Determination of 1,3,5-Triazine Herbicides in Environmental Samples by Capillary GC-MS-EI Selective Ion Monitoring Method

A new multi-residue method using gas chromatography–mass spectrometry electron ionization selective ion monitoring mode (SIM) has been developed for the simultaneous determination of eight 1,3,5-triazine herbicides such as 1,3,5-triazine-2,4-diamine (atrazine), ametryn, prometryn, propazine, terbuthylazine, terbutryn, and simazine simetryn in water and soil samples. Quantification is done using lindane (gamma benzene hexachloride) as an internal standard. A specific Capillary DB-Wax column of 30 m length, 0.32 mm internal diameter, and 0.25 µm film thickness is used for the separation of eight 1,3,5-triazine-2,4-diamine. The method was applied for the determination of residues in groundwater and soil samples. The lowest detection limit by GC-MS-SIM (selective ion monitoring mode) is 0.1 pg/mL. Recovery in water samples is in the range of 93–103%, and in soil samples, 91–102% for different individual compounds. Forty-five groundwater and soil samples were collected in and around Kancheepuram district in Tamilnadu (India), and they were analyzed for the respective residues. A detailed discussion of the GC-MS analysis results has been presented

Green fabrication of chitosan from marine crustaceans and mushroom waste: Toward sustainable resource utilization

The exoskeletons of crabs, shrimp, and fish are major waste. These wastes contain chitin, an abundant natural polymer found next to cellulose. Thus, disposal of this waste becomes a huge problem for the environment; besides this, reutilization boosts the circular economy. Chitin is partially deacetylated to yield the economically useful product of chitosan and is a heteropolymer. The current study isolated chitosan from mushrooms and various marine crustaceans, i.e., crabs, shrimp, and fish. Chitosan was extracted from marine crustaceans by demineralization, deproteination, and deacetylation. Later, extracted chitosan was characterized by physicochemical characteristics like deacetylation degree, ash content, protein, color, fat-binding capacity (FBC), water-binding capacity (WBC), pH, and moisture content. The result showed that chitosan yield ranges from 13.0% to 17.0%, the degree of deacetylation range from 82.0% to 85.0%, ash content range from 0.8% to 3.0%, and protein content is below 1.0%. The FBC and WBC range between 320% and 444% and 535% and 602%, respectively. The pH and moisture content range from 7.4 to 8.0 and from 2.0% to 4.0%, respectively. Overall, results specified that crustacean waste was an exceptional chitosan source with availability and production consistency

Research Trends in Smart Cost-Effective Water Quality Monitoring and Modeling: Special Focus on Artificial Intelligence

Numerous conventional methods are available for analyzing various water quality parameters to determine the water quality index. However, ongoing surveillance is necessary for large bodies of water. A water quality monitoring system supports a robust surface and groundwater ecosystem. Various tactics are used to improve aquatic habitats: identification of the precise chemical pollutants released into the aquatic environment; advancements in assessing ecological effects; and working on ways to enhance water quality through informing the public, communities, businesses, etc. In order to save the marine ecosystem and those who entirely depend on these enormous bodies of water, it is also crucial to continuously handle many data sets of water quality metrics. To predict the water quality index, this review paper provides an overview of water quality monitoring, the modeling and numerous sensors employed, and various artificial intelligence approaches. Various water quality models were proposed to assess pH, a few components, and alkalinity. Additionally, handling raw information for surface and groundwater quality metrics was studied using artificial intelligence techniques like neural networks

Synergistic effect of Echinops flower-like Copper sulfide@Cadmium sulfide heterostructure for high-performance all-solid-state asymmetric supercapacitor

The fascinating properties of transition metal chalcogenides, including their distinctive morphologies, large surface areas, crystal structures, tunnel bandgaps, and structural stability, have led to a widespread acceptance of these compounds as ideal electrode materials for energy and environmental applications. Incorporating additional metal chalcogenides into metal chalcogenides to form a heterostructure can further enhance their electrical conductivity and provide them with more active sites. Herein, a simple hydrothermal method is used to synthesize a heterostructure CuS@CdS nanocomposite by integrating Copper sulphide and Cadmium sulphide. X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy were used to ascertain the phase formation and structural properties of the synthesized compounds. The electrochemical properties of the obtained materials were investigated. In a three-electrode configuration, a heterostructure CuS@CdS nanocomposite delivers high-specific capacitance (543.6 Fg−1 at 1 Ag−1) with excellent rate capability and outstanding cycling stability. A heterostructure CuS@CdS nanocomposite and activated carbon were employed as the negative electrode/positive electrode to construct an all-solid-state asymmetric supercapacitor device for real-world applications. This fabricated device exhibits a high energy density of up to 34.9 Wh.kg−1 and power density of 798.1 W.kg−1 and outstanding cyclic stability and retains up to 95.5 % over 3000 cycles. The outstanding results demonstrate that the CuS/CdS nanocomposite is an appropriate electrode material for a high-performance supercapacitor

Recent developments in the use of heterogeneous semiconductor photocatalyst based materials for a visible-light-inducedwater-splitting system-a brief review

金沢大学先端科学・社会共創推進機構Visible-light-driven photoelectrochemical (PEC) and photocatalytic water splitting systems featuring heterogeneous semiconductor photocatalysts (oxynitrides, oxysulfides, organophotocatalysts) signify an environmentally friendly and promising approach for the manufacturing of renewable hydrogen fuel. Semiconducting electrode materials as the main constituents in the PEC water splitting system have substantial effects on the device’s solar-to-hydrogen (STH) conversion efficiency. Given the complication of the photocatalysis and photoelectrolysis methods, it is indispensable to include the different electrocatalytic materials for advancing visible-light-driven water splitting, considered a difficult challenge. Heterogeneous semiconductor-based materials with narrower bandgaps (2.5 to 1.9 eV), equivalent to the theoretical STH efficiencies ranging from 9.3% to 20.9%, are recognized as new types of photoabsorbents to engage as photoelectrodes for PEC water oxidation and have fascinated much consideration. Herein, we spotlight mainly on heterogenous semiconductor-based photoanode materials for PEC water splitting. Different heterogeneous photocatalysts based materials are emphasized in different groups, such as oxynitrides, oxysulfides, and organic solids. Lastly, the design approach and future developments regarding heterogeneous photocatalysts oxide electrodes for PEC applications and photocatalytic applications are also discussed. © 2021 by the authors

Anti-Methanogenic Effect of Phytochemicals on Methyl-Coenzyme M Reductase—Potential: In Silico and Molecular Docking Studies for Environmental Protection

Methane is a greenhouse gas which poses a great threat to life on earth as its emissions directly contribute to global warming and methane has a 28-fold higher warming potential over that of carbon dioxide. Ruminants have been identified as a major source of methane emission as a result of methanogenesis by their respective gut microbiomes. Various plants produce highly bioactive compounds which can be investigated to find a potential inhibitor of methyl-coenzyme M reductase (the target protein for methanogenesis). To speed up the process and to limit the use of laboratory resources, the present study uses an in-silico molecular docking approach to explore the anti-methanogenic properties of phytochemicals from Cymbopogon citratus, Origanum vulgare, Lavandula officinalis, Cinnamomum zeylanicum, Piper betle, Cuminum cyminum, Ocimum gratissimum, Salvia sclarea, Allium sativum, Rosmarinus officinalis and Thymus vulgaris. A total of 168 compounds from 11 plants were virtually screened. Finally, 25 scrutinized compounds were evaluated against methyl-coenzyme M reductase (MCR) protein using the AutoDock 4.0 program. In conclusion, the study identified 21 out of 25 compounds against inhibition of the MCR protein. Particularly, five compounds: rosmarinic acid (−10.71 kcal/mol), biotin (−9.38 kcal/mol), α-cadinol (−8.16 kcal/mol), (3R,3aS,6R,6aR)-3-(2H-1,3-benzodioxol-4-yl)-6-(2H-1,3-benzodioxol-5-yl)-hexahydrofuro[3,4-c]furan-1-one (−12.21 kcal/mol), and 2,4,7,9-tetramethyl-5decyn4,7diol (−9.02 kcal/mol) showed higher binding energy towards the MCR protein. In turn, these compounds have potential utility as rumen methanogenic inhibitors in the proposed methane inhibitor program. Ultimately, molecular dynamics simulations of rosmarinic acid and (3R,3aS,6R,6aR)-3-(2H-1,3-benzodioxol-4-yl)-6-(2H-1,3-benzodioxol-5-yl)-hexahydrofuro[3,4-c]furan-1-one yielded the best possible interaction and stability with the active site of 5A8K protein for 20 ns