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Triphenylamine (TPA)‐based Schiff base chemosensors ((E)‐2‐((4‐(diphenylamino)benzylidene)amino)phenol [TPA‐AP], (E)‐5‐(diphenylamino)‐2‐(((2‐hydroxyphenyl)imino)methyl)phenol [HTPA‐AP], and (E)‐5‐(diphenylamino)‐2‐((phenylimino)methyl)phenol [HTPA‐A]) were synthesized and explored the role of metal chelating hydroxyl functionality position for heavy metal ion sensing. TPA‐AP and HTPA‐AP showed Cu2+ ion‐induced chemical transformation and produced oxazole derivatives with turn‐on fluorescence. In contrast, HTPA‐A exhibited metal chelation‐induced turn‐on fluorescence for Zn2+ ion. The reactive chemical sensing of TPA‐AP and HTPA‐AP led to high selectivity of Cu2+, and other ions did not show any interference. The concentration‐dependent studies of Cu2+ and Zn2+ indicated the limit of detection (LOD) up to 6.07 × 10−7 and 4.6 × 10−7 M, respectively. Further, Cr3+, Fe3+, and Fe2+ coordination with TPA‐AP and HTPA‐AP exhibited visible color change from colorless to yellow. However, the yellow color was disappeared and becomes colorless due to imine hydrolysis. Interestingly, all three metal ions showed different rate of hydrolysis and color disappearance. TPA‐AP with Fe3+ exhibited fast hydrolysis and immediate color change whereas Fe2+ and Cr3+ required longer time. But HTPA‐AP and HTPA‐A produced stable complexes with Cr3+, Fe2+, and Sn2+ and Fe3+ alone showed hydrolysis. Thus, the present studies provide structural insight for designing reactive fluorescence and colorimetric Schiff base chemosensor for heavy metal ions. [ABSTRACT FROM AUTHOR]

Oximes, belonging to imines with the general formula of RR'C=NOH, are produced by the nucleophilic addition reaction between hydroxylamine with ketones or aldehydes, yielding corresponding aldoxime and ketoxime. The presence of hydrogen bond acceptor and donor is the classical feature of oxime‐containing structural framework. This review presents a summary of the role of oximes and its structure activity relationships including antimicrobial, anticancer, anti‐inflammatory, antihyperglycemic, insecticidal agents, along with their involvement in the treatment of organophosphorus poisoning. The review also focused on the pharmacological profile of lead molecules of several classes of oxime‐containing compounds. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulation is an in silico method used in the biomolecular level of research to study how the protein interacts with the target with time. It provides a detailed information of the protein dynamics and ligand structure with the crucial amino acid interactions. Monoamine oxidase B (MAO−B) is a crucial isoenzyme responsible for the catalyses of oxidative deamination of various biogenic amines in the brain and peripheral tissues. The selective inhibitors of MAO−B are considered as the management of symptoms of neurodegenerative disorders like Alzheimer's disease(AD) and Parkinson disease(PD). Recently the structural scaffolds containing chalcones, coumarins and chromones derived candidates shown potent, selective, competitive and reversible type of MAO−B inhibitors. The structural similarities between the above scaffolds can produce almost similar type of interactions in the inhibitor binding cavity of MAO−B. Numerous molecular simulation reports were supported by the above mentioned fact. The current review focus on the last ten year molecular dynamics report of chalcones, coumarins and chromones towards MAO−B inhibition. The review also focuses on the software details used in the MD dynamics simulation and the structural requirement from each class of compound for the recognition of MAO−B inhibitory activity. [ABSTRACT FROM AUTHOR]

During the past few years, single‐atom catalysts (SACs) have attracted considerable attention in electrolysis due to their outstanding catalytic performance and efficient atomic utilization. SACs exhibit a simple structure, high catalytic activity, consistent scaling relationships for single sites, and low metal content but their practical applications are still limited. Dual single‐atom catalysts (DACs), which feature excellent selectivity, high atomic utilization efficiency, and remarkable stability, are emerging as new frontiers in heterogeneous electrocatalysis. They increase catalytic activity by promoting synergistic effects between metal‐active sites. In this paper, we present a comprehensive overview of the latest developments in dual‐atom catalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). In addition, we explore the differences between homonuclear and heteronuclear configurations, the emergence of single/dual‐site metal catalysts, and the methods currently used for their synthesis. Lastly, this review discusses several perspectives for advancing the development of dual‐atom catalysts for OER and ORR electrocatalysis. [ABSTRACT FROM AUTHOR]

The current study reports tailoring the electronic donor structures of organic dyes to modify their optical and nonlinear optical (NLO) response properties. Five (5) tri‐phenyl amine (TPA) based Donor‐π‐Acceptor (D‐π‐A) organic dyes with the codes ICAA1, ICAA2, ICAA3, ICAA4, and ICAA5 were designed and investigated for their optical and NLO properties using quantum chemical methods. Optical and NLO properties of these dyes were studied by CAM‐B3LYP method and 6‐311G* basis set. The focus has been on the impact of adding secondary donors and shifting their substitutions at ortho (o), meta (m) and para (p) positions. Among all designed compounds, ICAA4 showed the highest amplitude of average third‐order NLO polarizability <γ>, which is calculated to be 1316 × 10−36 esu. Time‐dependent Density Functional Theory (TD‐DFT) method was used to determine how a change in the position of the donor affected the excitation energy (Eg) and NLO response properties. The findings showed that changing the position of the secondary donor results in a red shift among absorption spectra as well as the increase in their NLO responses. Complete process of intramolecular charge transfer (ICT) has been investigated in terms of different optical parameters such as frontier molecular orbitals (FMOs), molecular electrostatic potentials (MEPs), transition density matrix (TDMs), density of states (DOS), electron density difference (EDD), and natural bond orbital (NBO) analysis. Our calculations for study of ICT process indicate that p‐position of methoxy group performs better among all other positions and even it has better NLO response properties than the compound with three collective methoxy groups. The calculated Voc values of all designed molecules range from 1.09 to 1.30, all of them are positive while their ΔGinject is found to be in the range of −0.87 to −1.79 eV indicating their decent potential for photovoltaic applications. The studied optical, NLO and photovoltaic parameters illustrated that ICAA1 to ICAA5 are appropriate molecules not only for NLO applications but also for efficient photovoltaic purposes. [ABSTRACT FROM AUTHOR]

A hexaazatrinaphthylene [HAT] is a well‐known halogenated perylene diimide compound recognized for photochemical stability, high electron affinity, easy functionalization, and high conductivity. Based on density functional theory, optoelectronic and charge transport properties of HAT derivatives with electron‐donating, electron‐withdrawing, and push‐pull substituents, were investigated. The impact of substituting electron‐withdrawing groups (EWG), electron‐donating groups (EDG), and push‐pull substituents on various aspects, including molecular structure, frontier molecular orbitals, ionization energy, electron affinity, reorganization energy, crystal packing, and charge carrier mobility, is investigated. A crystal structure simulation method is employed to optimize potential arrangements of crystal packing for the molecules under examination. The presence of EWG, EDG, and push‐pull substitutions significantly affects the energy and distribution of electron density in the frontier molecular orbitals, leading to alterations in the absorption spectrum and charge transport properties. When adding various substituents to the core system, the different crystal packing motifs and varied intermolecular interactions of the examined molecules result in noticeably different transfer integrals. Due to higher hole reorganization energy and weak HOMO orbital overlapping, HAT derivative molecules exhibit better electron mobility. Among the studied molecules, HAT‐F and HAT‐F‐OCH3 molecules demonstrate better electron mobility with values of 0.49 and 2.36 cm2 V−1 s−1, respectively, and established the n‐channel characteristics. [ABSTRACT FROM AUTHOR]

For energy‐efficient and high‐power illumination systems, phosphor materials have attracted huge research attention over the recent decades. Herein, applying the first‐principles method, we investigate and predict the optoelectronic and structural properties of light‐harvesting phosphors Z2SiF6 (Z = K, Li, Na, Rb) as promising candidates for weight‐light‐emitting diodes w‐LEDs. The calculated direct energy band gaps are of order 1.56, 1.461, 1.479, and 1.585 eV for Z2SiF6 (Z = K, Li, Na, Rb), respectively, thus rendering the compound's semiconducting nature suitable for optoelectronic applications. Calculated structural properties show that Rb2SiF6 is the most stable compound among Z2SiF6 (Z = K, Li, Na, Rb). The optical properties in the energy range of 0–14 eV have been investigated using the well‐known (GGA) formulism available in the literature. Studied compounds are active optical materials as the value of their refractive index nω is between 1.0 and 2.0. Based on investigated optical parameters, we can say that Z2SiF6 (Z = K, Li, Na, Rb) are potential candidates for optoelectronic device applications like white LEDs (w‐LEDs). Thermodynamic parameters of Z2SiF6 (Z = K, Li, Na, Rb) are provided to establish the thermodynamic stability of these compounds. [ABSTRACT FROM AUTHOR]

Mamyshev oscillators (MOs) have attracted significant attention given their potential in yielding ultrafast lasers with high peak power. Based on step-like saturable absorbers and self-similar evolution in the gain fiber, MO technology features an advanced system capable of generating ultrastable femtosecond pulses with ultrahigh peak power. In this review, the principle of MO is presented in terms of their transmission function and tolerance to nonlinear phase shift and recent progress is reported in the advanced output performance of MO, manifested through high peak power, few-cycles, high repetition rate, and supercontinuum generation. MO with various operation wavelengths (1, 1.5, and 2 μm) are examined, and MO starting methods are fully discussed, followed by a detailed account of diverse potential applications in areas such as biomedical imaging and material processing. Based on current progress, the prospective challenges and future directions of MO are highlighted and discussed. [ABSTRACT FROM AUTHOR]

In recent decades, quantum dots (QDs) with tunable bandgap, large absorption coefficient, high quantum yield, multiexciton effect, and easy solution processing have unparalleled advantages in photoelectric conversion. Optoelectronic devices based on QDs of different composition have made great progress. However, there is still a lack of reviews on comparing the optoelectronic application level of semiconductor quantum dots (SQDs), perovskite quantum dots (PQDs), and carbon quantum dots (CDs), and also rarely providing a comprehensive summary of photocatalysis. First, this review almost completely summarizes advantages and disadvantages of common synthesis methods for QDs, especially pointing out the importance of optimization strategies for preparing high‐quality QDs such as ligand engineering, ion exchange, and purification separation. Then, compositions of SQD, PQD, CD, and corresponding optoelectronic properties are introduced, respectively. Next, the strengths and weaknesses of the four QDs structures are compared in detail. Finally, the flourishing development in various optoelectronic applications is separately demonstrated, and development degree of SQDs, PQDs, and CDs is compared to discover the most suitable application scenarios for each. On these bases, bottlenecks and opportunities are also put forwarded, hoping to stimulate more breakthroughs in this field. [ABSTRACT FROM AUTHOR]

Recently, the growing demand for a renewable and sustainable fuel alternative is contingent on fuel cell technologies. Even though it is regarded as an environmentally sustainable method of generating fuel for immediate concerns, it must be enhanced to make it extraordinarily affordable, and environmentally sustainable. Hydrogen (H2) synthesis by electrochemical water splitting (ECWS) is considered one of the foremost potential prospective methods for renewable energy output and H2 society implementation. Existing massive H2 output is mostly reliant on the steaming reformation of carbon fuels that yield CO2 together with H2 and is a finite resource. ECWS is a viable, efficient, and contamination‐free method for H2 evolution. Consequently, developing reliable and cost‐effective technology for ECWS was a top priority for scientists around the globe. Utilizing renewable technologies to decrease total fuel utilization is crucial for H2 evolution. Capturing and transforming the fuel from the ambient through various renewable solutions for water splitting (WS) could effectively reduce the need for additional electricity. ECWS is among the foremost potential prospective methods for renewable energy output and the achievement of a H2‐based economy. For the overall water splitting (OWS), several transition‐metal‐based polyfunctional metal catalysts for both cathode and anode have been synthesized. Furthermore, the essential to the widespread adoption of such technology is the development of reduced‐price, super functional electrocatalysts to substitute those, depending on metals. Many metal‐premised electrocatalysts for both the anode and cathode have been designed for the WS process. The attributes of H2 and oxygen (O2) dynamics interactions on the electrodes of water electrolysis cells and the fundamental techniques for evaluating the achievement of electrocatalysts are outlined in this paper. Special emphasis is paid to their fabrication, electrocatalytic performance, durability, and measures for enhancing their efficiency. In addition, prospective ideas on metal‐based WS electrocatalysts based on existing problems are presented. It is anticipated that this review will offer a straight direction toward the engineering and construction of novel polyfunctional electrocatalysts encompassing superior efficiency in a suitable WS technique. [ABSTRACT FROM AUTHOR]

The increasing demand for searching highly efficient and robust technologies in the context of sustainable energy production totally rely onto the cost‐effective energy efficient production technologies. Solar power technology in this regard will perceived to be extensively employed in a variety of ways in the future ahead, in terms of the combustion of petroleum‐based pollutants, CO2 reduction, heterogeneous photocatalysis, as well as the formation of unlimited and sustainable hydrogen gas production. Semiconductor‐based photocatalysis is regarded as potentially sustainable solution in this context. g‐C3N4 is classified as non‐metallic semiconductor to overcome this energy demand and enviromental challenges, because of its superior electronic configuration, which has a median band energy of around 2.7 eV, strong photocatalytic stability, and higher light performance. The photocatalytic performance of g‐C3N4 is perceived to be inadequate, owing to its small surface area along with high rate of charge recombination. However, various synthetic strategies were applied in order to incorporate g‐C3N4 with different guest materials to increase photocatalytic performance. After these fabrication approaches, the photocatalytic activity was enhanced owing to generation of photoinduced electrons and holes, by improving light absorption ability, and boosting surface area, which provides more space for photocatalytic reaction. In this review, various metals, non‐metals, metals oxide, sulfides, and ferrites have been integrated with g‐C3N4 to form mono, bimetallic, heterojunction, Z‐scheme, and S‐scheme‐based materials for boosting performance. Also, different varieties of g‐C3N4 were utilized for different aspects of photocatalytic application i. e., water reduction, water oxidation, CO2 reduction, and photodegradation of dye pollutants, etc. As a consequence, we have assembled a summary of the latest g‐C3N4 based materials, their uses in solar energy adaption, and proper management of the environment. This research will further well explain the detail of the mechanism of all these photocatalytic processes for the next steps, as well as the age number of new insights in order to overcome the current challenges. [ABSTRACT FROM AUTHOR]

Use of MXenes (Ti3C2Tx), which belongs to the family of two‐dimensional transition metal nitrides and carbides by encompassing unique combination of metallic conductivity and hydrophilicity, is receiving tremendous attention, since its discovery as energy material in 2011. Owing to its precursor selective chemical etching, and unique intrinsic characteristics, the MXene surface properties are further classified into highly chemically active compound, which further produced different surface functional groups i. e., oxygen, fluorine or hydroxyl groups. However, the role of surface functional groups doesn't not only have a significant impact onto its electrochemical and hydrophilic characteristics (i. e., ion adsorption/diffusion), but also imparting a noteworthy effect onto its conductivity, work function, electronic structure and properties. Henceforth, such kind of inherent chemical nature, robust electrochemistry and high hydrophilicity ultimately increasing the MXene application as a most propitious material for overall environment‐remediation, electrocatalytic sensors, energy conversion and storage application. Moreover, it is well documented that the role of MXenes in all kinds of research fields is still on a progress stage for their further improvement, which is not sufficiently summarized in literature till now. The present review article is intended to critically discuss the different chemical aptitudes and the diversity of MXenes and its derivates (i. e., hybrid composites) in all aforesaid application with special emphasis onto the improvement of its surface characteristics for the multidimensional application. However, this review article is anticipated to endorse MXenes and its derivates hybrid configuration, which is discussed in detail for emerging environmental decontamination, electrochemical use, and pollutant detection via electrocatalytic sensors, photocatalysis, along with membrane distillation and the adsorption application. Finally, it is expected, that this review article will open up new window for the effective use of MXene in a broad range of environmental remediation, energy conversion and storage application as a novel, robust, multidimensional and more proficient materials. [ABSTRACT FROM AUTHOR]

The current study involves the synthesis of two azomethine compounds, (E)‐2‐((6‐nitrobenzo[d][1,3]dioxol‐5‐yl)methylene)amino)phenol (2AP6NO) and (E)‐2‐((4‐ethylbenzylidene)amino)phenol (2AP4ETH), as well as their theoretical investigations. The synthesized azomethine compounds were then characterized by combustion analysis (CHN), FT‐IR, NMR (1H and 13C), and single crystal X‐ray diffraction (SC‐XRD) analysis. The SC‐XRD study confirmed the enol tautomeric form of 2AP6NO as well as 2AP4ETH. The strong and comparatively weak intermolecular interactions were elaborated by Hirshfeld surface analysis. For both compounds, intermolecular interaction energies between the pair of molecules, energy framework, and void analysis were calculated to visualize the three‐dimensional topology of the crystal packing. Additionally, quantum chemical computations were also utilized to study the optical and nonlinear optical (NLO) response. The molecular geometries were optimized at the M06‐2X/6‐311G* method and equated to their respective experimental counterparts. The third‐order NLO polarizabilities were also calculated at the same level of theory. The calculated average third‐order NLO polarizabilities were 62.55×10−36 esu and 55.08×10−36 esu, respectively, predicting the modest behavior of the above compounds when displaying NLO properties. [ABSTRACT FROM AUTHOR]

Nanomaterials with remarkable optical, mechanical, and electrical properties have shed new light on various fields including optoelectronics, sensors, biomedicine, and ultrafast photonics. Particularly, owing to their nonlinear optical properties, fast recovery time, and broadband operation, nanomaterials are well qualified as saturable absorbers in ultrafast pulsed lasers. Over the development of the past decades, various nanomaterials have been developed as saturable absorbers, which contribute to a diversity of lasers with excellent performance. Therefore, it is important for researchers to provide a landmark of the applications of nanomaterials in ultrafast photonics concerning cutting‐edge development. Herein, the integration and applications of nanomaterials in ultrafast photonics are reviewed. First, end‐face, lateral, as well as photonic crystal fibers padding integration methods are introduced along with their process and characteristics. Then the ultrafast applications of nanomaterials including carbon‐based (carbon nanotubes and graphene), typical 2D (topological insulators, transition metal dichalcogenides, black phosphorus, and MXenes), and metal‐based nanomaterials (gold, silver, copper, and metal oxides) are summarized. Major parameters of ultrafast lasers and features of each nanomaterial are presented simultaneously. Finally, the perspectives of nanomaterials for further development in ultrafast photonics are discussed. [ABSTRACT FROM AUTHOR]

Being one of the foremost enticing and intriguing innovations, heterogeneous photocatalysis has also been used to effectively gather, transform, and conserve sustainable sun's radiation for the production of efficient and clean fossil energy as well as a wide range of ecological implications. The generation of solar fuel‐based water splitting and CO2 photoreduction is excellent for generating alternative resources and reducing global warming. Developing an inexpensive photocatalyst can effectively split water into hydrogen (H2), oxygen (O2) sources, and carbon dioxide (CO2) into fuel sources, which is a crucial problem in photocatalysis. The metal‐free g‐C3N4 photocatalyst has a high solar fuel generation potential. This review covers the most recent advancements in g‐C3N4 preparation, including innovative design concepts and new synthesis methods, and novel ideas for expanding the light absorption of pure g‐C3N4 for photocatalytic application. Similarly, the main issue concerning research and prospects in photocatalysts based g‐C3N4 was also discussed. The current dissertation provides an overview of comprehensive understanding of the exploitation of the extraordinary systemic and characteristics, as well as the fabrication processes and uses of g‐C3N4. [ABSTRACT FROM AUTHOR]

Magnetically guided drug transportation is a technique in which magnetic pharmaceutical transporters in organisms are controlled by applied magnetic forces to deliver drugs to the desired location. Different magnetic drug delivery systems (MDDSs) are developed to treat a variety of illnesses, particularly cancer and neurological disorders. However, a unique magnetic setup is required in each application for an effective magnetically guided drug aiming to direct the drug‐carrying nanocarriers to the intended area. The current and future perspectives of MDDS are investigated in this study by considering their biological functions, deliverable efficiency, complexity, and the nature of the externally applied magnetic field. Despite the fact that MDDSs have low cytotoxicity, regulated magneto reactivity, extended circulation lifespan, and high surface stability, very few clinical studies have been conducted to date in order to achieve optimized therapeutic efficacy before entering the market. In recent studies, the development of novel magnetic medication transporting carriers is preferred over direct magnetic medication administration. Better functional magnetic targeting technologies are required for such breakthroughs to enter clinical trials. Because MDDSs are unlikely to work in all clinical situations, more focused research is needed to replace or improve the strategy for treating multiple illnesses. [ABSTRACT FROM AUTHOR]

The current study was designed to investigate the effects of expandable graphite (EG) on fire protection properties of intumescent fire‐retardant coating for steel structures. Several formulations of intumescent coating were prepared and tested according to ISO 834 for char expansion. The chars were found without cracks and bonded with the steel substrate. The results showed that the coating slowly degraded during the test and char remained in contact with vertically tested coated substrate. The coated substrates were also tested for weather resistance using humid and ultraviolet environment. The char was characterized by using FESEM, XRD, FTIR, TGA, and XPS analysis. FESEM examined char morphology of the coatings after furnace fire test. XRD and FTIR showed the presence of graphite, borophosphate; boron oxide and sassolite in the char. TGA and DTGA results disclosed that EG improved the residual mass of coating. XPS analysis showed the percentages of carbon and oxygen are 48.50 and 43.45 in char of formulation with 12.8% EG. The results of weathering test coatings showed decreased in char expansion because of a humidity and UV light. The formulation with 9.8% EG showed the maximum char expansion and high residual mass among the formulations investigated in this study. The weathering tested coated samples showed their capability of fire protection. [ABSTRACT FROM AUTHOR]

In the last few years, Monoamine oxidase (MAO) have emerged as a target for the treatment of many neurodegenerative diseases including anxiety, depression, Alzheimer's, and Parkinson's diseases. The MAO inhibitors especially selective and reversible inhibitors of either of the isoenzymes (MAO‐A & MAO‐B) have been given more attention as both the form have different therapeutic properties and hence can be used for different neurological disorders. The lack of selective and reversible inhibitors available for both the enzymes and severity of the neuronal disorder in society have opened a new door to the researchers to carry out large and dedicated researches in this field. Among the several classes of the molecule as the inhibitors, coumarins hold a rank as a potent scaffold with its ease of synthesis, high therapeutic potential, and reversibility in inhibiting MAOs. The current review is an update of the research in the field that covers the works during the last six years (2014–2020) with a major focus on the SAR of the coumarin derivatives including synthetic, natural, and hybrids of coumarins with FDA‐approved drugs. [ABSTRACT FROM AUTHOR]

Among the N‐containing heterocyclic compounds, quinazoline‐4‐(3H)‐one derivatives have been the center of attraction of medicinal and synthetic chemists due to their excellent versatility in biological activities that are witnessed by many approved drugs available in the market which contains quinazoline as main pharmacophore unit. This review mainly focuses the recent and current progresses in quinazoline derivatives as an acetylcholinesterase (AChE) and monoamine oxidase (MAO)‐B inhibitors. The review has leanings towards the molecular determinants and structure‐activity relationships (SAR) of quinazoline derivatives on AChE and MAO inhibitory potencies. [ABSTRACT FROM AUTHOR]

Studies on copper zinc tin sulpher selenide (CZTSSe) thin‐film material and its applications as a base material are intensively being researched since it is an earth‐abundant, inexpensive, flexible, and interesting material for next‐generation optoelectronic technologies. Apropos, this study explores and reports the synthesis of CZTSSe thin films and their key optoelectronics characteristics. The reported films are fabricated on a soda‐lime glass substrate by using a physical vapor deposition technique, and then annealed from 250 to 450 °C. From the X‐ray diffraction analysis, the structure of the as‐deposited thin films is found to be amorphous in nature. Annealed thin films of CZTSSe exhibit polycrystalline nature with an average crystallite size of 46.3 nm in tetragonal structure. To determine the bandgap energy, as well as optical properties, the visible spectrophotometer, and four‐probe techniques, are used. From the measurements, the bandgap energy of the annealed film is found to be 1.64 eV at 450 °C which is in the optimal range as an absorber layer for solar cell devices. Similarly, by employing the four‐probe technique, I–V characteristics for the as‐deposited thin films, the material shows non‐ohmic behavior whereas the annealed film demonstrates partially ohmic with a resistance of 670 ohms. [ABSTRACT FROM AUTHOR]

A significant amount of glycerol has been generated by the epidemic increment in several biodiesel industries globally, which should be utilized for the biodiversity of biodiesel. The synthesis of Solketal‐acetone glycerol as a possible fuel additive is one of the most crucial glycerol recovery paths. State‐of‐the‐art reviews on batch and continuous processes to produce Solketal and possible reaction mechanisms are presented. The design of reactors and catalysts is taken into consideration and the factors influencing the yield of the Solketal process are discussed in detail. Finally, conclusions with future recommendations are reported. The utility of glycerol for acetals and ketals is of current importance for scientists seeking to find the best working conditions by testing the different catalysts, reactants, temperatures, and reactor designs. [ABSTRACT FROM AUTHOR]

This research aims to study the effect of ammonium polyphosphate and expandable graphite on the intumescent coating formulations (ICF). The coating presented in this research article is based on carbon source expandable graphite (EG), blowing agent melamine, acid source ammonium polyphosphate (APP), epoxy resin as a binder with polyamide amine. The stability of the developed coating was verified at 950°C for 1‐hour fire test. The results showed that the coating is stable and well bond with the steel substrate. The char was characterized by using FESEM, XRD, FTIR, DTA, TGA, XPS, Py‐GCMS and Weathering Test. The morphology of the char was studied by SEM of the coating after furnace fire test. XRD and FTIR show the presence of graphite, borophosphate; boron oxide and sassolite in the residual char. TGA and DTG disclosed that EG improved the residual mass of coating. XPS analysis showed the char residue of IF5‐APP‐EG contains carbon and oxygen contents 47.50 and 40.70, respectively. Py‐GCMS analysis described that the IF5‐APP‐EG released less gaseous compounds. The weathering test illustrated that's the char expansion of coatings samples was decreased due to the presence of a humid environment and UV light. The IF5‐APP‐EG showed the maximum char expansion, lower substrate temperature and high residual weight among the studied formulations. [ABSTRACT FROM AUTHOR]

The present investigation uses a dual approach to study the copper (II) complex [Cu(phen)3]. (ClO4)2.HL.CH3CN (1) and its cationic complex‐ [Cu(II)(phen)3]2+ (1 a), where, HL = 4‐Bromo‐2((Z) ‐(naphthalene‐4‐ylimino)methyl)phenol, phen=1,10‐phenanthroline. The complex (1) crystallized in the triclinic system of the space group P‐1 with two molecules in the unit cell and reveals a distorted octahedral geometry. Inspiring by recent developments to find a potential inhibitor for the COVID‐19 virus, we have also performed molecular docking study of [Cu(phen)3]+2 to see if our novel complex shows an affinity for the main protease (Mpro) of COVID‐19 spike protein. Interestingly, the results are found quite encouraging where the binding affinity and inhibition constant were found to be −8.400 kcal/mol and 0.661 μM, respectively, for the best‐docked confirmation of [Cu(II)(Phen)3]+2 complex with Mpro protein. This binding affinity is reasonably well as compared to recently known antiviral drugs. For instance, the binding affinity of [Cu(II)(Phen)3]+2 complex is found to be better than recently docking results of chloroquine (−6.293 kcal/mol), hydroxychloroquine (−5.573 kcal/mol) and remdesivir (−6.352 kcal/mol) with Mpro protein. Thus, we believe the broad‐spectrum functional properties of our complex will provoke not only the interest of material chemists in materials designing but also incite the drug designing community. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 coronavirus has been recognized the causative agent of the recent and ongoing pandemic. Effective and specific antiviral agents or vaccines are still missing, despite a large plethora of compounds have been proposed and tested worldwide. New compounds are requested urgently and virtual screening can offer fast and robust predictions to investigate. Moreover, natural compounds were shown to exert antiviral effects and can be endowed with limited side effects and wide availability. Our approach consisted in the validation of a docking protocol able to refine the most suitable candidates, within the 31000 natural compounds of the natural product activity and species source (NPASS) library, interacting with the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) spike glycoprotein. After the refinement process two natural compounds, castanospermine and karuquinone B, were shown to be the best‐in‐class derivatives in silico able to target an essential structure of the virus and to act in the early stage of infection. [ABSTRACT FROM AUTHOR]

Hybrid nanostructures of amorphous cobalt oxide (Co3O4) and crystalline gold nanoparticles (AuNPs) showed strongly enhanced OER activity compared to pure amorphous Co3O4. Particularly, gold nanorods (Au NRs) integrated amorphous Co3O4 nanostructures (aCo3O4/Au NRs) required significantly low overpotential (225 mV) to produce geometric current density and needed 336 and 398 mV for achieving current density of 100 and 400 mA/cm2, respectively. Further, aCo3O4/Au NRs displayed good stability over 40 h at 336 mV. [ABSTRACT FROM AUTHOR]

The synthesis of a nanofluid from multiwalled carbon nanotubes (MWCNTs) and Kapok seed oil by a one‐step method is reported. The nanofluid showed excellent stability of nanoparticle dispersion in the base fluid. Furthermore, this study deals with the prediction of the thermal conductivity of the MWCNTs‐kapok seed oil nanofluid. To improve the prediction of the thermal conductivity of the nanofluid, the artificial neural network (ANN) computing approach was used with different algorithms including the back‐propagation, Levenberg‐Marquardt, and genetic algorithm (GA). Finally, the ANN‐GA model is recommended for the prediction of thermal conductivity with higher accuracy. [ABSTRACT FROM AUTHOR]

Schiff base molecules of 1–4 ((E)‐N′‐benzylidene‐2‐hydroxybenzohydrazide derivatives) showed structure controlled solid state fluorescence tuning, reversible stimuli induced fluorescence switching and highly selective Co2+ sensing. The strong intramolecular H‐bonding between imine and amine facilitates excited state intramolecular proton transfer (ESIPT) and large red shifted solid state fluorescence. Positional isomers and substitutional change tuned the solid state fluorescence (460 to 605 nm). The substituents and positions control stimuli‐induced fluorescence switching. ESIPT fluorophores showed strong fluorescence in DMF (Φf=0.057 to 0.35 compared to quinine sulphate). ESIPT fluorophores (2–4) exhibited highly selective fluorescence sensing of Co2+ ions without significant interference from other metal ions. Concentration dependent studies of fluorophores show the detection limit (LOD) of 54 nM that is much lower than the Environmental Protection Agency (EPA) guideline value (1.7 μM) in drinking water. Solid state fluorescence of ESIPT fluorophores have been made use to fabricate solid fluorescence assay (PVA polymer composite thin films) and demonstrated highly selective fluorescence sensing of Co2+ upon dipping into aqueous metal ions solution. Thus, the present studies demonstrate the versatility of Schiff base molecules for developing ESIPT fluorophores for stimuli responsive materials and highly selective fluorescence sensing both in solution and solid state. [ABSTRACT FROM AUTHOR]

Herein, we reported the imino phosphonate compounds: (4‐methoxy‐benzylidene‐amino‐phenyl‐methyl‐phosphonic acid diethyl ester (MBPDE), 4‐hydroxy‐benzylidene‐amino‐phenyl‐methyl‐phosphonic acid diethyl ester (HBPDE) and 4‐hydroxy‐3‐methoxy‐benzylidene‐amino‐phenyl‐methyl‐phosphonic acid diethyl ester (HMBPD) form the chemical reaction of diethyl (α‐amino benzyl)phosphonate hydrochloride and substituted benzaldehyde. These compounds were characterized by various spectroscopic techniques: FT‐IR, Mass, UV–VIS, 1H NMR and 13 C NMR. Additionally, the optimized molecular structures, FT‐IR, natural bond orbitals (NBOs), frontier molecular orbitals (FMOs), non‐linear optical (NLO) properties were calculated by the density functional theory (DFT) using the B3LYP functional with the 6–311+G(d,p) basis set. Moreover, UV–Visible spectrum of MBPDE, HBPDE and HMBPD were predicted in different solvents using the time dependent TD‐DFT [B3LYP/6‐311+G(d,p)] method using Polarizable Continuum Model (PCM). The non‐linear optical (NLO) properties were calculated by M06 functional with the 6–311+G(d,p) basis set. A synergistic relationship is observed between the experimental and theoretical findings. NBO analysis provided insights about the stability and charge delocalization of the entitled molecules. The global reactivity descriptors were achieved through HOMO‐LUMO energies. The efficiency of the entitled molecules concerning charge transfer and participation in diverse chemical reactivities were figured out perceptibly by applying the frontier molecular orbitals (FMOs) analysis. The average polarizability <α> values: 277.184, 261.332 and 280.254 a.u. of the MBPDE, HBPDE and HMBPD were determined respectively. The total first hyperpolarizability (βtot) values of the MBPDE, HBPDE and HMBPD were also obtained to be 992.900, 781.527 and 1107.526 a.u. respectively. The compound HMBPD comprising of higher magnitude of average polarizability and the total first hyperpolarizability (βtot) values than MBPDE and HBPDE molecules. Moreover, NLO properties of urea molecule were found smaller in comparison to the MBPDE, HBPDE and HMBPD. The medicinal importances of these novel compounds as well as its contribution towards nonlinear optical field are our future targets. [ABSTRACT FROM AUTHOR]

Bioactive glass was first synthesized by L. Hench in 1971. There are many studies on the properties of several metals and metal ions dopants used in the SiO2‐CaO‐P2O5 system of bioglasses, such as Ag, Cu, Zn, and Fe. A number of authors have carried out research related to the influence of silver oxide on the properties of bioglasses. However, publications on the properties of elastomer‐based composites containing bioactive glasses are relatively scarce. We have not found in the literature studies discussing how silver oxide concentration in bioglasses of the CaO‐SiO2‐P2O5‐Ag2O system affects the significant properties of a natural rubber biocomposite. In this regard, the purpose of the present work is to investigate the aforementioned influence on the properties of this type of composites, namely, vulcanization, physicomechanical, thermal, dynamic, dielectric, electric, and thermoconductive characteristics. We have established those parameters of the composites to be impacted considerably by both degree of filling with bioglass and the silver oxide content in the latter. The improvement in the composites thermostability and some of their physicomechanical performance is the most significant. The volume resistance decreases, and the thermal conductivity coefficients increase. Results from scanning electron microscopy and energy‐dispersive X‐ray (EDX) analyses have confirmed the influence of silver oxide initially on the phase composition of the bioglass, hence on the properties of the biocomposites through changes in the bioglass used as filler. The dielectric characteristics of some of the biocomposites suggest that they can be used as substrates and insulating layers in flexible antennas for short‐range wireless communications. [ABSTRACT FROM AUTHOR]

The room temperature and task‐specific ionic liquids nowadays have been investigated widely for the removal of sulfur compounds from the natural gas streams. However, the major challenge is the recovery of the desulfurized ionic liquids, which need some significant developments. In this study, two magnetic ionic liquids including the 1‐butyl‐3‐methylimidazolium tetrachloroferrate [Bmim][FeCl4] and 1‐butyl‐3‐methylimidazolium thiocyanate [Bmim][SCN] were investigated for their interaction with the sulfur‐rich compound, that is, dibenzothiophene. The ionic liquids samples were desulfurized and then regenerated with the co‐solvent hexane. The samples were characterized and investigated with the analytical techniques including the Fourier‐transform infrared spectroscopy, ultraviolet–visible absorption analysis, thermogravimetric analysis, and detailed analysis by Raman spectroscopy. The desulfurization results demonstrated that there is no significant influence of the dibenzothiophene molecules on the basic structures of ionic liquids. The regeneration results revealed that the high polarity of the co‐solvent hexane successfully dissolve the dibenzothiophene and efficiently separated from the ionic liquids. Hence, the work present here in this study could be applied for the extractive removal of sulfur compounds from ionic liquids for their regeneration using high polarity co‐solvent hexane. [ABSTRACT FROM AUTHOR]

Lithium–oxygen (Li–O2) batteries have received much attention due to the superior theoretical energy density. However, commercialization is still hindered by several challenges including the high charge overpotential and poor cycling stability. Herein, small particle‐stacked TiO2 microspheres are successfully synthesized through a facile hydrolysis and hydrothermal method. Such unique architectures provide 3D framework with more catalytically active sites and rich porosity for the storage of discharge products and oxygen diffusion. Li–O2 batteries utilizing the TiO2 microspheres electrode show a much higher specific capacity and a lower overpotential than those with pure carbon nanotube (CNT) electrodes. Moreover, they exhibit an enhanced cycling stability and TiO2 microspheres show great potential as a promising catalyst for Li–O2 batteries. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries have attracted a lot of attention in recent years due to their high theoretical capacity of 1675 mAh g−1 and low cost. However, the shuttle effect caused by the dissolution and migration of polysulfides and the destruction of cathode particles due to volume expansion during lithiation are key issues for their practical application. Herein, a one‐pot hydrothermal preparation of a VS2@S composite as a cathode for lithium–sulfur batteries is reported. The VS2@S composite shows uniform and flowerlike aggregates of nanoparticles of sizes around 50–80 nm. The porous structure among VS2@S nanoparticles can accommodate the volumetric expansion occurring during sulfur lithiation. Adsorption capability testing proves a strong interaction between VS2 and polysulfides. Therefore, the as‐prepared VS2@S composite exhibits good electrochemical performance, with a discharge capacity of 413 mAh g−1 after 200 cycles at a 1 C rate. After various rate cyclings from 0.1 to 2 C, the VS2@S electrode delivers a reversible capacity of 884 mAh g−1 when the current density switches to 0.1 C, demonstrating a notable improvement compared with pure sulfur electrodes. [ABSTRACT FROM AUTHOR]

The new aminocoumarin derivatives 3‐[1‐(3‐hydroxyanilino)ethylidene]‐3H‐chromene‐2,4‐dione, (1), 3‐[1‐(4‐hydroxyanilino)ethylidene]‐3H‐chromene‐2,4‐dione, (2), and 3‐[1‐(2‐hydroxyanilino)ethylidene]‐3H‐chromene‐2,4‐dione, (3), all C17H13NO4, were synthesized by reacting an equimolar amount of 3‐acetyl‐4‐hydroxycoumarin and the corresponding aminophenol in absolute ethanol. Structural and spectroscopic analysis of these phases revealed that derivatives (1) and (2) are isomers of previously reported (3) [Brahmia et al. (2013). Acta Cryst. E69, o1296]. The crystal structures of meta derivative (1) and para derivative (2) were ab initio determined from powder X‐ray diffraction data using the direct‐space approach. Both (1) and (2) adopt the orthorhombic space group P212121. These isomers show hydrogen bonds and rich π–π stacking, together with π...H interactions, which are built by conjugated systems of coumarin and phenol rings. In the crystalline lattice, the packing of (1) and (3) are mainly stabilized through O—H...O hydrogen bonding between neighbouring coumarin molecules, while hydrogen bonds between coumarin and water molecules build the stable crystal structure of derivative (2). A big similarity in the skeletons of the IR spectra of these isomers was noticed. Derivative (2) exhibits two weak bands which were not present in the spectra of the other two derivatives, at 2370 and 2948 cm−1, which can be assigned to the O—H vibrations of the solvent (H2O) trapped in the structure of (2). These aminocoumarin derivatives display absorption maxima in the visible region, attributed to π–π delocalization involving the whole electronic system of the compounds with a considerable charge‐transfer character originating from the aminophenyl ring and pointing towards the coumarin system which is characterized by a high electron‐accepting character. Additionally, the isolated molecular ground‐state geometries were optimized at the PBE0/TZP level and the electronic properties, molecular electrostatic potential and Hirshfeld charges were determined. [ABSTRACT FROM AUTHOR]

Inorganic membranes can operate under harsh conditions. However, successful synthesis of inorganic membranes is still challenging, and its performance depends on many factors. This work reports the effect of dip‐coating duration, inlet pressure, and inlet flow rate on the flux, permeability, and selectivity of silica membranes. A silica membrane was prepared by the deposition of silica sol onto porous alumina support. The permeability test was conducted at 100 °C using a single gas of CO2 and CH4. The highest flux was observed at the maximum inlet pressure and inlet flow rate for the membrane prepared at the minimum dip‐coating duration. The neural network modeling of the membrane predicted permeabilities showed a considerably high validity regression (R ≈ 0.99) of the predicted data linked to the experimental sets. The separation factor (α) was the highest at the maximum dip‐coating duration. The synthesized silica membrane has potential for CO2/CH4 separation under harsh operating conditions. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this study, a new pressure drop method has been used to investigate the kinetics of carbon dioxide reaction with aqueous blend of 2‐amino‐2‐ethyl‐1,3‐propanediol (AEPD) with piperazine (PZ). The blending of a small amount of PZ with AEPD has a significant effect on the observed rate constant, kobs. It was observed that kobs values of the blend increased more than twice than the summation of kobs values of individual alkanolamines. The reaction kinetics in this study were modeled by assuming a termolecular mechanism. The addition of 0.1 mol/L of PZ to 1 mol/L AEPD exhibited an observed rate constant, kobs of 8824.1 s−1, which is comparable to other alkanolamine mixtures. Hence, PZ/AEPD mixtures can be potentially used for rapid carbon dioxide capture. [ABSTRACT FROM AUTHOR]

Abstract: Polystyrene‐poly(N‐isopropylmethacrylamide‐acrylic acid) [pSty‐p(NIpmam‐AC)] core shell microgels loaded with silver nanoparticles (NPs) as a recyclable catalyst for rapid reduction of Congo Red (CR) dye in aqueous medium is reported for the first time. Catalytic activity of Ag‐pSty‐p(NIpmam‐AC) core shell composite microgels is measured by adopting the reduction of CR as a benchmark reaction. Restriction of Ag NPs in single layered p(NIpmam‐AC) shell of Ag‐pSty‐p(NIpmam‐AC) core shell composite microgels enhances the diffusion of reactants to access the Ag NPs, surface during reaction with respect to previously reported core shell and homogenous composite microgels, and thus enhances the rate of CR reduction. The solid nonresponsive pSty core induces easy recyclability in core shell composite microgel catalysts. The effect of different reaction parameters such as amount of catalyst, concentration of NaBH4 and CR on the reaction completion time for CR reduction, as well as on the value of apparent rate constant (kapp), is also studied by keeping all other parameters constant, separately. Reduction efficiency of Ag‐pSty‐p(NIpmam‐AC) catalyst is also measured under different reaction conditions for the reduction of CR. A slight decrease in the percentage activity of Ag‐pSty‐p(NIpmam‐AC) catalyst is observed for up to four cycles for CR reduction. The reported Ag‐pSty‐p(NIpmam‐AC) composite microgel catalysts can be used to degrade other pollutants. [ABSTRACT FROM AUTHOR]

In this paper, we present the design of five new derivatives of triphenylamine dyes with variable thiophene rings (0-5) and shed light on their electrooptical and charge-injection properties. Computational techniques are used to study the effect of the thiophene moieties on the properties of interest, i.e., how the number of thiophene rings in π-conjugated systems influence the absorption spectra and electron injection of the dyes. The results show that the absorption spectra gradually became broad and red-shifted (384-542 nm) with the number of thiophene units. The effect of thiophene units on the performance of sensitizers in dye-sensitized solar cells is also determined. During theoretical examination, the electron injection efficiency (Φinject) and light harvesting efficiency ( LHE) are determined. Results indicate that the selection of appropriate lengths of conjugated bridges in the dye sensitizer is very important in designing high-efficiency dyes. [ABSTRACT FROM AUTHOR]

This study spotlights the fundamental insights about the structure and static first hyperpolarizability ( β) of a series of 2,4-dinitrophenol derivatives (1-5), which are designed by novel bridging core modifications. The central bridging core modifications show noteworthy effects to modulate the optical and nonlinear optical properties in these derivatives. The derivative systems show significantly large amplitudes of first hyperpolarizability as compared to parent system 1, which are 4, 46, 66, and 90% larger for systems 2, 3, 4, and 5, respectively, at Moller-Plesset (MP2)/6-31G* level of theory. The static first hyperpolarizability and frequency dependent coupled-perturbed Kohn-Sham first hyperpolarizability are calculated by means of MP2 and density functional theory methods and compared with respective experimental values wherever possible. Using two-level model with full-set of parameters dependence of transition energy (Δ Ε), transition dipole moment ( μ0) as well as change in dipole moment from ground to excited state (Δ μ), the origin of increase in β amplitudes is traced from the change in dipole moment from ground to excited state. The causes of change in dipole moments are further discovered through sum of Mulliken atomic charges and intermolecular charge transfer spotted in frontier molecular orbitals analysis. Additionally, analysis of conformational isomers and UV-Visible spectra has been also performed for all designed derivatives. Thus, our present investigation provides novel and explanatory insights on the chemical nature and origin of intrinsic nonlinear optical (NLO) properties of 2,4-dinitrophenol derivatives. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The development of electrochemically active and stable anode catalysts for the photoelectrochemical splitting of water molecules via biophotovoltaic cells (BPVs) utilizing microalgae receives a prime importance in green energy sector. Herein, we report the ruthenium oxide (RuO2)/tungsten oxide (WO3) composite nanofibers based photoanode for the application of high performance and durable BPV. The sequential arrangement of 6 nm sized RuO2/WO3 spherical particles constitutes the nanofibrous morphology and a number of surface active sites and structural integrity of nanofibers demonstrate the excellent and stable photo‐oxidation currents. Under the light regime, RuO2/WO3/carbon cloth photoanode exhibits the substantial BPV power and current densities with an excellent durability. Thus this systematic study evokes the fundamental understanding on the electron generation and transference mechanisms, which offers new dimensions in the development of high performance and durable BPVs. [ABSTRACT FROM AUTHOR]