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In this study, we have conducted a comparative analysis of the structural ordering of short oligoetherimide chains (dimers) near the bounding surface, depending on the structure of that surface. In order to clarify the possibility of oligoetherimide ordering along the symmetry axes of graphene, two types of bounding surfaces were considered: graphene, with a regular discrete position of interaction centers (carbon atoms), and a smooth, structureless impermeable wall. The chemical structures of the considered dimers consist of two repeating units of BPDA-P3, ODPA-P3, or aBPDA-P3 thermoplastic polyetherimides. Using all-atom molecular dynamics simulations, the process of structural ordering of the dimers near the surface of the graphene or wall was established. The ODPA-P3 and BPDA-P3 dimers form an ordered state near the graphene surface, while the aBPDA-P3 dimers do not demonstrate structural ordering. The simulation results confirmed that the ordering direction of the BPDA-P3 and ODPA-P3 dimers near the graphene surface is chosen randomly. Comparison of the oligoetherimide structure formed near the attracting wall without a symmetrical location of the interaction centers shows the similarity of the ordering of dimers near the graphene surface and the wall. As in the case of the graphene surface, the ordering of oligoetherimide molecules near the structureless wall demonstrates one direction of ordering. Therefore, we confirmed that the key factor for the onset of ordering is the presence of a confining surface, rather than the symmetrical arrangement of interaction centers in the substrate structure. [ABSTRACT FROM AUTHOR]

Based upon global-minimum searches and first-principles electronic structural calculations, we present the perfectly planar B6O50/−/2− (1–3) systems. Notably, the C2v B6O50/− (1–2) clusters mark a groundbreaking advancement as the first boron oxide clusters to feature a five-membered ring. Both structures exhibit remarkable similarity, each characterized by a central B3O2 ring surrounded by three terminal BO groups. However, a notable difference lies in the bond lengths within the B3O2 core, which are uniform in the former but uneven in the latter. Detailed canonical molecular orbital and AdNDP analyses reveal the delocalized π bonds over the B3O2 ring, affirming the π aromaticity of B6O5−. The Cs B6O52− (3) cluster showcases a chain-like arrangement with three terminal BO groups and a typical OBO group linked to a B2 core, emphasizing the crucial role of electrons in shaping the structure. Detailed chemical bonding analyses reveal the presence of dual three-center four-electron (3c–4e) π hyperbonds in 3, shedding further light on its unique bonding characteristics. Moreover, this study comprehensively extends the B(BO)n0/− (n = 1–5) series and provides valuable perspectives on their structural evolution. [ABSTRACT FROM AUTHOR]

Zero-dimensional (0D) hybrid metal halides (HMHs) have emerged as a promising platform for exploring excitation-dependent multicolor luminescent materials owing to their diverse crystal structures and chemical compositions. Nevertheless, understanding the mechanism behind excitation-dependent emissions (EDEs) in 0D HMHs and achieving precise modulation remains challenging. In this work, the delicate regulations on the EDE of 0D (DMEDABr)4SnBr3I3 (DMEDA: N, N′-dimethylethylenediamine) with mixed halogens are achieved under low temperature and high pressure, respectively. The inhomogeneous halogen occupation at the atomic scale leads to the formation of Br-rich and I-rich SnX6 (X = Br, I) octahedra, which act as distinct luminescent centers upon photoexcitation. At low temperatures, the narrowed photoluminescence spectra could distinguish the individual emissions from different luminescent centers, resulting in a pronounced EDE of (DMEDABr)4SnBr3I3. In addition, the contraction and distortion of the luminescent SnX6 (X = Br, I) centers at high pressure further result in different degrees of emission shifts, giving rise to the gradual emergence and disappearance of EDE. This work elucidates the underlying mechanism of EDE in 0D HMHs and highlights the crucial role of halogens in determining the optical properties of metal halides. [ABSTRACT FROM AUTHOR]

QM/MM methods have been used to study electronic structure properties and chemical reactivity in complex molecular systems where direct electronic structure calculations are not feasible. In our previous work, we showed that non-polarizable force fields, by design, describe intermolecular interactions through pairwise interactions, overlooking many-body interactions involving three or more particles. In contrast, polarizable force fields account partially for many-body effects through polarization, but still handle van der Waals and permanent electrostatic interactions pairwise. We showed that despite those limitations, polarizable and non-polarizable force fields can reproduce relative cooperativity achieved using density functional theory due to error compensation mechanisms. In this contribution, we assess the performance of QM/MM methods in reproducing these phenomena. Our study highlights the significance of the QM region size and force field choice in QM/MM calculations, emphasizing the importance of parameter validation to obtain accurate interaction energy predictions. [ABSTRACT FROM AUTHOR]

The ionization energies (IEs) of RuC, RhC, OsC, IrC, and PtC are assigned by the measurement of their two-photon ionization thresholds. Although late transition metal–carbon bonds are of major importance in organometallic chemistry and catalysis, accurate and precise fundamental thermochemical data on these chemical bonds are mainly lacking in the literature. Based on their two-photon ionization thresholds, in this work, we assign IE(RuC) = 7.439(40) eV, IE(RhC) = 7.458(32) eV, IE(OsC) = 8.647(25) eV, IE(IrC) = 8.933(74) eV, and IE(PtC) = 9.397(32) eV. These experimentally derived IEs are further confirmed through quantum chemical calculations using coupled-cluster single double perturbative triple methods that are extrapolated to the complete basis set limit using a three-parameter mixed Gaussian/exponential extrapolation scheme and corrected for spin–orbit effects using a semiempirical method. The electronic structure and chemical bonding of these MC species are discussed in the context of these ionization energy measurements. The IEs of RuC, RhC, OsC, and IrC closely mirror the IEs of the corresponding transition metal atoms, suggesting that for these species, the (n + 1)s electrons of the transition metals are not significantly involved in chemical bonding. [ABSTRACT FROM AUTHOR]

Partially fluorinated dimyristoylphosphatidylcholines (DMPCs) involving double alkyl chains are employed to control the phonon generation in thin films, which is examined by infrared (IR) spectroscopy coupled with multiple-angle incidence resolution spectrometry (MAIRS). technique. Compounds having perfluoroalkyl (Rf) chains are known to exhibit phonon bands in IR spectra because of the strong dipole–dipole interactions. Since the phonon bands of an organic matter have a similar shape to the normal absorption bands, however, recognition of the phonon modes is difficult and confusing for IR spectroscopists. Here, we show that MAIRS works out for finding phonon modes in monolayers: the Berreman shift is readily captured by the MAIRS in-plane and out-of-plane (OP) spectra. By measuring the longitudinal-optic (LO) energy-loss function spectrum of a bulk sample, the degree of molecular aggregation in the monolayer is also revealed by comparing the OP spectrum of the monolayer to the LO one. In addition, partially fluorinated DMPC compounds having both hydrocarbon and Rf chains are prepared, and they are used to obstruct the self-aggregation of the Rf groups in the film. As a result, the phonon characteristics are mostly lost in the MAIRS spectra as expected. [ABSTRACT FROM AUTHOR]

For photosensitive polyurethane systems, reactive diluents are indispensable components whose main role is to reduce the viscosity of the polyurethane prepolymer to meet the requirements of the photocurable 3D printing technology for high fluidity of the precursor solution. Generally, the reactive diluent would be involved in the photocuring reaction, which in turn has a remarkable impact on the mechanical, reaction kinetics, and thermodynamic characteristics of the photosensitive polyurethane system. However, this feature is usually neglected in the study of photosensitive urethane acrylate (PUA) systems, so there is a considerable necessity to investigate the mechanism of active diluents in the photocured reaction of PUA systems. In this work, the effects of α-methyl groups along the chains of diluent molecules on the photoreaction kinetics, photocurable 3D printing, mechanical and mechanical properties, and thermodynamic characteristics of PUAs were investigated employing hydroxyethyl methacrylate and hydroxyethyl acrylate as active diluents, respectively. The relationship between chemical structure and kinetics of PUA systems was also elucidated by using dynamic mechanical analysis tests. The results demonstrated that the α-methyl group blocks the migration of reactive radicals, reduces the efficiency of the photoreaction, and causes an increase in the rigidity and strength of the molecular chain. This study not only revealed the effect of α-methyl on the kinetic mechanical and thermal performance of PUA systems but also paves the way for the development of a new class of photosensitive PUA materials used for the photocurable 3D printing technology. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) is a mucopolysaccharide alternately linked by glucuronic acid and n‐acetylglucosamine, which is usually used as a moisturizer in cosmetics. In this study, HA derivative (FA‐HA) was prepared by modifying sodium hyaluronate with ferulic acid (FA). The chemical and morphological structure of FA‐HA were characterized by UV, FTIR, 1H‐NMR, DLS and TEM. The results showed that FA was grafted onto HA chains via ester bonds and self‐assembled into nanoparticles in aqueous solution. The introduction of FA endowed the nanoparticles with antioxidant function. The FRAP value of 10 mg/mL FA‐HA was 1.985 mM, and the clearance rate of O2−, DPPH+ and ABTS+ could reach 83.13%, 88.86% and 99.48% respectively. Moreover, FA‐HA can be used as Pickering emulsifiers to stabilize the emulsion. The results showed that the size of emulsion droplets decreased as the concentration of FA‐HA increased. When the mass ratio of oil to water was 7/3, the emulsion droplets were the smallest. The addition of sodium chloride will increase the size of emulsion droplets, destroying the stability of the emulsion. In addition, FA‐HA was also universal and was capable of emulsifying alkanes, esters, and natural oils, which was expected to be applied in the cosmetics and food fields. [ABSTRACT FROM AUTHOR]

The escalating concentration of carbon dioxide in the atmosphere is a pressing environmental concern, necessitating the development of efficient technologies for CO2 reduction and utilization. In this context, metal–organic frameworks (MOFs) emerge as promising catalysts due to their tunable structures and unique chemical properties. This study focuses on the synthesis, characterization, and evaluation of amino-functionalized MOFs with cobalt and nickel nodes for the electrochemical reduction of CO2. Electrochemical investigations reveal that a cobalt-based MOF primarily facilitates the production of methane, demonstrating high selectivity and efficiency under controlled conditions. In contrast, a nickel-based MOF exhibits a broader array of reduction products, including methane, CO, and ethanol, with a significant conversion efficiency. These differences underscore the impact of the central metal node on the catalytic activity and product distribution. This comprehensive study not only advances our understanding of MOF-based catalysts for CO2 reduction but also underscores the significance of molecular engineering in enhancing the selectivity and efficiency of these processes. By demonstrating the potential of amino-functionalized MOFs with specific metal nodes, we contribute to the development of sustainable solutions for carbon capture and utilization, aligning with global efforts to mitigate climate changes and foster a green chemical industry. [ABSTRACT FROM AUTHOR]

Twelve compounds, including eleven bisabolane-type sesquiterpenoids (1 − 11), and one bacillibactin (12) were identified from marine-derived fungus Aspergillus sydowii SCSIO 41041 isolated from Creseis acicula. The chemical structures were elucidated by the basis of spectroscopic evidences, including HRESIMS, NMR and optical rotation. Biologically, all compounds were evaluated for their acetyl cholin-esterase (AChE) enzyme, pancreatic lipase (PL) enzyme, neuraminidase (NA) and phosphodiesterase 4 (PDE4) inhibitory activities. Compound 12 displayed significant inhibitory activity against neuraminidase (NA) with an IC50 value of 24.0 μM, which was equivalent to the positive drug oseltamivir phosphate (IC50 value of 20.0 μM). And the NA inhibitory activity was confirmed by molecular docking analysis. [ABSTRACT FROM AUTHOR]

Heparosan (Hep), an unsulfated glycosaminoglycan (GAG), has a chemical structure closely resembling that of hyaluronic acid (HA). However, Hep has not been utilized in injectable dermal fillers as HA has been. In this article, injectable Hep crosslinked hydrogels were fabricated using 1,4-butanediol diglycidyl ether (BDDE) as the crosslinking agent. The physicochemical properties of the Hep crosslinked hydrogel, including pH and osmolality, were verified to be compatible with human physiology. The Hep crosslinked hydrogels exhibit higher viscoelasticity and a longer in vitro lifespan compared to HA crosslinked hydrogels. Furthermore, biocompatibility and safety assessments supported their potential use as injectable dermal fillers. [ABSTRACT FROM AUTHOR]

Diblock copolymers consisting of higher hydrophobic styrene and hydrophilic N-hydroxyethylacrylamide (HEAAm) segments were successfully synthesized via direct two-step atom transfer radical polymerization. Polystyrene (PS) homopolymers were synthesized using methyl 4-(bromo-methyl) benzoate initiator in N,N′- dimethylformamide (DMF) in the presence of Cu(I)Br/pentamethyldiethylene tetramine (PMDETA) catalyst system at 90 and 110 °C in nitrogen atmosphere. PS was used as macro-initiator for the synthesis of PS-b-PHEAAm polymer. Block copolymerizations were carried out in pure DMF in the presence of the same catalyst system at 110 °C while argon was used for deoxygenation and inert environment. Block copolymer was purified through dialysis into deionized water using a dialysis tubing (MWCO 3500, cellulose membrane). The number average molecular weight of PS polymers (Mn = 2240, 3250 and 10,800 Da) was determined by size exclusion chromatography using tetrahydrofuran (THF) as eluent. The chemical structures, functional groups and actual compositions of copolymer were determined using instrumental data, c.f. elemental analysis, attenuated total reflectance infra-red and proton—nuclear magnetic resonance (1H-NMR) spectroscopy analysis. Thermo-gravimetric analysis confirms that diblock copolymer has higher thermal stability than PS homopolymer. Co-solvent effect on particle formation was investigated by regulating dielectric constant. It is revealed that THF/DMF (9:1) provides susceptible environment for the formation of smallest size (13 ± 4 nm) particle. This synthetic route would establish a direct synthesis of diblock copolymer with antagonistic segments for advanced technological applications. [ABSTRACT FROM AUTHOR]

A novel series of 4-aminopiperidin-3,4-dihyroquinazoline-2-uracil derivatives (9a-9 L) were logically designed and synthesized as potent DPP4 inhibitors as antidiabetic agents. Chemical structure of all new compounds were confirmed by different spectroscopic methods. The designed compounds were evaluated using a MAK 203 kit as DPP4 inhibitors in comparison with Sitagliptin. The biological evaluation revealed that compound 9i bearing chloro substitution on phenyl moiety of 6-bromo quinazoline ring had promising inhibitory activity with IC50 = 9.25 ± 0.57 µM. The toxicity test of all compounds confirmed safety profile of them. Kinetic studies showed that compound 9i exhibited a competitive-type inhibition with a Ki value of 12.01 µM. Computational approach supported the rationality of our design strategy, as 9i represented appropriate binding interactions with the active sites of DPP4 target. MD simulation outputs validated the stability of ligand 9i at DPP4 active site. Also, Density functional theory (DFT) including HOMO-LUMO energies, ESP map, thermochemical parameters, and theoretical IR spectrum was employed to study the reactivity descriptors of 9i and 9a as the most and least potent compounds respectively. Based on the DFT study, compound 9i was softer and, as a result, more reactive than 9a. Taken together, our results showed the potential of 4-aminopiperidin-3,4-dihyroquinazoline-2-uracil derivatives as promising candidates for developing some novel DPP4 inhibitors for managing of type 2 diabetes. [ABSTRACT FROM AUTHOR]

Background: The efficacy of mRNA-based vaccines and therapies relies on lipid nanoparticles (LNPs) as carriers to deliver mRNA into cells. The chemical structure of ionizable lipids (ILs) within LNPs is crucial in determining their delivery efficiency. Results: In this study, we synthesized 623 alkyne-bearing ionizable lipids using the A3 coupling reaction and assessed their effectiveness in mRNA delivery. ILs with specific structural features—18-carbon alkyl chains, a cis-double bond, and ethanolamine head groups—demonstrated superior mRNA delivery capabilities. Variations in saturation, double bond placement, and chain length correlated with decreased efficacy. Alkynes positioned adjacent to nitrogen atoms in ILs reduced the acid dissociation constant (pKa) of LNPs, thereby hindering mRNA delivery efficiency. Conversion of alkynes to alkanes significantly enhanced mRNA delivery of ILs both in vitro and in vivo. Moreover, combining optimized ILs with cKK-E12 yields synergistic LNPs that showed markedly augmented mRNA expression levels in vivo. Conclusions: Overall, our study provides insights into the structure–function relationships of ILs, providing a foundation for the rational design of ILs to enhance the efficacy of LNPs in mRNA delivery. [ABSTRACT FROM AUTHOR]

The present study aims to improve the mechanical strength of hydrogels via a simplified method, involving the creation of a nanocomposite hydrogel using polyvinyl alcohol (PVA) incorporated with un‐modified multiwalled carbon nanotubes (um‐MWCNTs). Departing from conventional freezing–thawing cycles, our research employs a facile approach, in which high‐shear mixing along with solvent exchange with deionized water was utilized. Morphological analysis unveiled a compact and dense microstructure within the nanocomposite hydrogel in correlation with MWCNT concentration. Attenuated total reflection‐Fourier transform infrared spectroscopy (ATR‐FTIR) elucidated the chemical structure of PVA/um‐MWCNTs hydrogel nanocomposite. Rheological studies on the viscoelastic properties indicated the formation of more "solid‐like" structure in the developed hydrogel nanocomposite. Broadband dielectric spectroscopy revealed alterations in dielectric properties of the fabricated PVA/um‐MWCNTs hydrogel nanocomposite corresponding to MWCNTs content in the PVA matrix. This comprehensive investigation highlights the impact of minimal MWCNTs concentration on the rheology, mechanical, and dielectric properties of developed PVA/um‐MWCNTs hydrogel nanocomposite. [ABSTRACT FROM AUTHOR]

To demonstrate the feasibility of obtaining low-molecular-weight organic films (below 200 Da) using non-solvent PVD processes, glucose layers were produced via pulsed laser deposition (PLD) and pulsed electron beam deposition (PED) methods. Glucose was chosen due to its fundamental role in various biological processes, and because this low-molecular-weight compound is a solid at room temperature, which is required for both techniques. The physical and chemical structures of the deposited glucose layers were characterized by optical, scanning electron, and atomic force microscopy, as well as by X-ray diffraction, X-ray photoelectron, and infrared spectroscopy. Both PLD and PED methods resulted in glucose layers with good chemical structure preservation (with minor oxidation observed in PED) while yielding films with distinct physical properties. This opens up the possibility of tailoring organic layers with specific characteristics depending on the application, by choosing the deposition method. [ABSTRACT FROM AUTHOR]

The application of wood-plastic composites (WPCs) in outdoor settings has led to growing emphasis on their aesthetics and weathering. Therefore, it is necessary to study the effect of inorganic pigments on the weathering behavior of WPCs. In order to reveal the effect of inorganic pigments on the aging process of composites, wheat straw fiber/polyvinyl chloride composites (WSFPs) incorporating inorganic pigments were prepared, and accelerated weathering tests of the different colored WSFPs were carried out, and the changes of chemical structure, color stability, three-dimensional morphology, mechanical properties and physical properties of composites during weathering were investigated. The results showed that WSFPs with inorganic pigment showed high color stability and weather resistance during accelerated weathering. After weathering for 480 h, the color change exhibited by WY was the least, only 13.00, and its tensile, flexural and impact properties decreased by 5.14%, 8.72% and 3.10%, respectively. This study demonstrates that inorganic pigments not only enhance the aesthetics of WSFPs through coloration, but also effectively improve their weather resistance. Inorganic pigments help maintain the vibrant color and structural integrity of the material during long-term use. [ABSTRACT FROM AUTHOR]

We established an efficient method using high-speed countercurrent chromatography (HSCCC) combined with preparative high-performance liquid chromatography (prep-HPLC) for isolating and purifying Gelsemium elegans (G. elegans) alkaloids. First, the two-phase solvent system composed of 1% triethylamine aqueous solution/n-hexane/ethyl acetate/ethanol (volume ratio 4:2:3:2) was employed to separate the crude extract (350 mg) using HSCCC. Subsequently, the mixture that resulted from HSCCC was further separated by Prep-HPLC, resulting in seven pure compounds including: 14-hydroxygelsenicine (1, 12.1 mg), sempervirine (2, 20.8 mg), 19-(R)-hydroxydihydrogelelsevirine (3, 10.1 mg), koumine (4, 50.5 mg), gelsemine (5, 32.2 mg), gelselvirine (6, 50.5 mg), and 11-hydroxyhumanmantenine (7, 12.5 mg). The purity of these seven compounds were 97.4, 98.9, 98.5, 99, 99.5, 96.8, and 85.5%, as determined by HPLC. The chemical structures of the seven compounds were analyzed and confirmed by electrospray ionization mass spectrometry (ESI-MS), 1H-nuclear magnetic resonance (1H NMR), and 13 C-nuclear magnetic resonance (13 C NMR) spectra. The results indicate that the HSCCC-prep-HPLC method can effectively separate the major alkaloids from the purified G. elegans, holding promising prospects for potential applications in the separation and identification of other traditional Chinese medicines. [ABSTRACT FROM AUTHOR]

The Tutte polynomial is a classical polynomial graph invariant that provides important information about the structure of a graph. In this study, we focus on the Tutte polynomials for typical silicate molecular networks and benzenoid systems, and derive exact formulas for the considered polycyclic chemical graphs. We also determine the explicit closed-form analytic expressions for the number of spanning trees, connected spanning subgraphs, spanning forests, and acyclic orientations of these chemical polycyclic graphs. Our approach employs a combinatorial decomposition technique, which is a general method that can be easily extended to other 2-connected chemical polycyclic networks. This research contributes to a better understanding of the topological properties of chemical structures and has potential applications in chemistry and materials science. [ABSTRACT FROM AUTHOR]

The global pandemic caused by the novel virus SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2), also known as COVID-19, is now a serious public health concern that has affected people worldwide. The condition has become worse due to a lack of adequate treatment. To combat the pandemic, several drugs are being investigated. A topological index (or molecular descriptor) is a numerical parameter that correlates the molecular structure of a chemical compound to its various physico-chemical properties and plays a significant role in the development of QSPR/QSAR (quantitative structure–property relationship/quantitative structure-activity relationship) models. In this study, we evaluate the degree-based topological indices (namely, the Nirmala index, first and second inverse Nirmala indices, geometric-quadratic and quadratic-geometric indices) of nine antiviral drugs (namely, Molnupiravir, Remdesivir, Chloroquine, Ritonavir, Theaflavin, Arbidol, Hydroxychloroquine, Thalidomide and Lopinavir) used in the remedy of COVID-19 patients, with the help of their respective M-polynomials. Also, we calculate the neighborhood degree sum-based indices of Molnupiravir by using its neighborhood M-polynomial (that is, NM-polynomial). In addition, we execute the correlation analysis among the topological indices and physico-chemical properties of these antiviral drugs. Furthermore, we demonstrate the QSPR models for strong correlation through the linear, quadratic and cubic regression analysis to appraise the effectiveness of the topological indices. And, the squared correlation coefficients obtained from the performed curvilinear regression models are compared with those acquired in the previous studies. The obtained topological indices and established QSPR models which may be helpful to predict the pharmacokinetic properties of these antiviral drugs and in the discovery of new drugs related to the medication for the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

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Plasma technology for generating activated water has garnered significant interest among researchers for its antimicrobial properties post-treatment. This study aimed to produce chitosan hydrogels incorporating various types and concentrations of plasma activated water (PAW) derived from tap water and purified water. Initially, the physicochemical properties of PAW, including pH, electrical conductivity (EC), and total dissolved solids (TDS), were assessed, revealing a notable decrease in pH and an increase in EC and TDS post-activation. Chitosan hydrogels were then synthesized using PAW and subjected to Fourier Transform Infrared Spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM) analyses. Results indicated a minimal impact on the chemical structure of the hydrogels post-PAW addition. TGA and DSC results revealed differences between tap water-based hydrogels and purified water-based hydrogels, indicating the presence of impurities or minerals in tap water. SEM observations depicted morphological alterations with increased plasma exposure, potentially enhancing antimicrobial activity. In degradation and swelling tests, the hydrogels exhibited pH sensitivity, maintaining integrity in neutral and alkaline media while dissolving in acidic conditions. Hemocompatibility and antimicrobial efficacy were confirmed through hemolysis tests and antibacterial/antifungal assays, particularly in hydrogels with prolonged water activation times, attributed to reactive species in PAW. These findings underscore the potential of these hydrogels as disinfectants in the biomedical field. [ABSTRACT FROM AUTHOR]

Flotation process is the most common beneficiation method of almost all types of minerals. The desirable result of the process is dependent on various factors. One of the most effective parameters in this regard is the particle size. Generally, acceptable results can be obtained by adjusting particle size in an optimum and specific range, and flotation of coarser or finer than this range is always intricate and problematic. Specifically, in the case of fine and ultra-fine particles, this complexity becomes more aggravated most importantly because of the massive specific area and the reduction of particle-bubble collision and attachment probabilities. There is a vast amount of literature on fine particles flotation using micro- and nanobubbles, intensified flotation machines, and different chemical reagents, however, the most promising procedure in this regard can be considered as the increment of particle sizes via agglomeration and flocculation techniques combined with flotation. This technique provides great opportunities for recovering fine and ultra-fine particles economically and increment of sustainable processing. However, there are some gaps and obscure points such as the exact mechanism of bubble-floc adsorption, interaction between flocs and reagents, pulp properties variations due to flocculation, and its effects on flotation behavior. This paper categorizes and describes diverse aspects of this combined novel technique in detail and provides a comprehensive source for readers to have a deeper insight into this intricate process. First of all, the physicochemical characteristics of the process have been described thoroughly from perspectives including the type and structure of applied chemicals, influential parameters, and involved adsorption mechanisms. It is followed by a detailed interpretation of different floc-flotation techniques as well as their cons and pros, effective parameters, and possible improvement and optimization approaches. Further, some similar techniques such as oil agglomeration, hydrophobic-hydrophilic Separation, and carrier flotation were described and compared with present technique of floc-flotation. Technological aspects of the process as well as an industrial case study of this technique were other areas which have been investigated in this paper and finally, scientific and technical gaps in this branch of flotation technology were extracted to open-up new horizon ahead of researchers active and/or interested in this field. [ABSTRACT FROM AUTHOR]

Photocatalytic reduction of 4-nitrophenol to 4-aminophenol has a broad development prospect and potential economic value. In this study, we prepared for the first time Co3O4-modified sulfur-doped polyimide (Co3O4/SPI) catalyst using a facile ion-exchange technique. The chemical structure, morphology and photoelectronic performance of the catalysts were analyzed by different characteristics. The results showed that Co3O4 displayed high dispersibility; increasing the specific surface area of SPI provided more reactive sites. Meanwhile, the Co3O4 modification successfully constructed a Co3O4/SPI type-II heterostructure with a suitable band gap, which significantly improved the absorption of visible light and the photogenerated electron–hole pair separation efficiency of SPI. These factors caused Co3O4/SPI to exhibit higher photocatalytic activity than pure SPI, which facilitated the photocatalytic reduction of 4-nitrophenol to 4-aminophenol by Co3O4/SPI. At 5 min of visible light irradiation, the conversion of 4-nitrophenol was 100%, while that of SPI was 23%. Moreover, the photocatalyst showed good stability after five cycles. Finally, the mechanism of photocatalytic reduction of 4-nitrophenol by Co3O4/SPI was also discussed. The Co3O4/SPI provides a new approach for the cost-effective reduction of 4-nitrophenol and obtains high-value-added 4-aminophenol. [ABSTRACT FROM AUTHOR]

Electrochemical nanoimprinting (ECNI) is a microstructure fabrication technique that combines metal-assisted chemical etching (MaCE) with nanoimprint lithography. A significant advantage of ECNI over traditional MaCE is the reusability of the stamp and excellent pattern consistency. This work studies the effects of various etchant components on etching results, discussing the associative parameters separately. Experimental results demonstrate that ECNI successfully fabricates bi-layer microstructures with flat surface morphology, where the second layer has a feature size of 40 μ m and a depth of 12.5 μ m. These findings highlight ECNI's potential as a scalable method for producing complex multi-layer structures, positioning it as a promising solution for large-scale microfabrication of semiconductors. [ABSTRACT FROM AUTHOR]

Anthocyanins, a type of phenolic compound, are found in plants. They are high-value food and pharmaceutical ingredients with improved health benefits and biological functions. However, there are certain drawbacks to using anthocyanins in the food and pharmaceutical industries, such as low stability and vulnerability to severe environmental conditions such as light, pH, temperature, and oxygen which could have a significant impact on the health-promoting properties. Encapsulation is one of the most preferred processing methods since it helps preserve the health benefits of anthocyanin. Choosing an appropriate strategy entails consideration of processing parameters, equipment availability, and application aims. Electrospun nanofibers were used as a novel platform for anthocyanin encapsulation. Because of their superior properties, they can improve the encapsulation efficiency, bioactivity, and bioaccessibility of anthocyanin. The current review examines the chemical structure of anthocyanin and the principles and advantages of electrospinning as an encapsulating method in depth. Finally, the current limitations and opportunities for advancing electrospinning in food packaging and medicine delivery are explored. [ABSTRACT FROM AUTHOR]

Summary: This study explores the potential of hydrothermal extraction as an innovative valorisation method for the simultaneous production of gelatin and fish oil from fish byproducts. It offers an environmentally friendly alternative to conventional solvent‐based techniques by minimising the use of chemical solvents and water. We researched various major commercial freshwater fish species: striped catfish, catfish, and tilapia, and achieved a gelatin product that reflects commercial standards in chemical structure, gel strength, and pH level. The striped catfish gelatin showed the highest gel strength and viscosity (66.01 ± 0.83 g bloom and 15.3 ± 0.1 cP), but was produced at a lower yield than the catfish gelatin. On the other hand, striped catfish produced the highest yield of fish oil (13.56 ± 0.21%) and has the highest omega 3 content (3.72 ± 0.02%) than other fish oil. This innovative study demonstrates the potential of hydrothermal extraction as a sustainable method for producing gelatin and fish oil, offering eco‐friendly and nutritional benefits across a range of applications. [ABSTRACT FROM AUTHOR]

Microbial pigments have extensive applications in the food, cosmetic, and biopharmaceutical industries. In this study, a pigment-rich actinomycete identified as Streptomyces tauricus was isolated from soil, and the solubility and stability of its were investigated. The pigment was separated and purified through thin-layer chromatography (TLC), column chromatography, and high performance liquid chromatography (HPLC) to determine its components. The chemical structure of the pigment was characterized through infrared (IR) spectroscopy, gas chromatography-mass spectrometry (GC–MS), tandem mass spectrometry (MS/MS–MS), and nuclear magnetic resonance (NMR). Additionally, the antioxidant properties and safety profile of the pigment were assessed. The S. tauricus pigment was bright, vivid brownish-red, intracellular, and fat-soluble; it exhibited considerable photothermal stability and maintained its color below pH 7. The presence of Cu2+, Fe2+, and Fe3+ ions markedly influenced the pigment's characteristics. The pigment comprised primarily purple and orange components. The purple component, which is relatively rare in microbial sources, was subjected to detailed study. The core structure of the purple component was identified as methylbenzanthracene dione, which has high antioxidant activity and no toxicity in brine shrimp assays. Due to its resilience to high temperatures and acidic environments, coupled with its bioactivity and lack of toxicity, this pigment may serve as a promising candidate for various industrial and food applications. [ABSTRACT FROM AUTHOR]

The genus Armadillo is represented by 26 species, three of which are recorded from Tunisia: the Mediterranean A. officinalis Duméril, 1816, and the endemic A. mayeti Simon, 1885 and A. pseudomayeti Mattern, 1999. In this paper, the endemic species A. mayeti is redescribed, its morphological diagnostic characters are illustrated, and its stridulation apparatus structure and biochemical composition are highlighted for the first time using optical and scanning electronic microscopy. The stridulation apparatus, visible dorsally on propodus of pereopods 4 and 5, is structured in a row of chain scales. Regarding its chemical composition, the scale contains numerous elements with a high carbon content (C = 58.71%) followed by calcium (Ca = 19.63%), oxygen (O = 13.98), aluminium (Al = 4.81), copper (Cu = 1.02), iron (Fe = 0.63), potassium (K = 0.43), and silicon (Si = 0.20). Its distribution is extended and its status on the International Union for Conservation of Nature (IUCN) Red List is reported. Armadillo mayeti is then compared with the widespread Mediterranean A. officinalis for diagnostic purposes on the bases of morphological features and the stridulation apparatus structure focusing on the chemical composition. The taxonomic status of A. pseudomayeti is discussed. [ABSTRACT FROM AUTHOR]

This paper presents the first example of the formation of acetonyl tridentate CˆNˆN complexes of arylbipyridines in the reaction of chloroplatinum complexes with acetone in the presence of alkali. The chemical structure of obtained substances was established by means of 1H,13C NMR, COSY, HSQC, and HMBC techniques. The attribution of all proton and carbon signals in NMR spectra was performed using 1D and 2D NMR experiments for the synthesized acetonyl cycloplatinated complexes. A comparative analysis of the values of the C‐Pt spin‐spin coupling constants of the same order was carried out, which showed a significant difference in bond lengths and valence angles inthe cyclic fragments of the arylbipyridine ligand. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) and poly(vinyl alcohol) (PVA) stand out among biodegradable polymers to be inserted in the food packaging sector; these can have their properties enhanced when mixed with each other or with the addition of additives (antioxidants). This work initiated a study with BC/PVA blends incorporated with antioxidant food complex (EXT), using concentrations of 0, 1.08, 2.14, and 4.30 g/L of EXT in the fermentation medium. Blends produced were evaluated for water retention capacity, chemical structure, morphology, crystallinity, thermal stability, antioxidant activity, and permeability to water vapor. Pure and incorporated blends did not show a significant difference in water retention capacity and morphology. However, incorporated blends showed alteration in the infrared spectrum, decreased crystallinity, thermal stability, permeability to water vapor, and increased antioxidant activity. These results confirm the incorporation of EXT and make the blends promising against moisture and oxidative reactions in the food packaging sector. [ABSTRACT FROM AUTHOR]

The end-of-life tyres (ELTs) are currently critical environmental and societal problems due to their large quantity and chemical structure. The thermochemical process has been acknowledged as a viable option for extracting material and energy from ELTs. This review outlines the cutting-edge thermochemical techniques for recycling tyres, encompassing gasification, pyrolysis, and incineration. Additionally, it delves into the primary by-products, including oil, gas, and char. The advantages and disadvantages of each process are discussed in terms of energy efficiency, product yield, and environmental impact. The optimal reaction conditions for each product yield and quality are identified and described. The correlation between process parameters and product composition, yield and quality is clarified. Products after further processing are illustrated with specific examples. Future research directions such as upgrade of char product using low-temperature partial-oxidation process are given. This review is novel in its comprehensive synthesis of the latest advancements in thermochemical techniques for recycling ELTs, highlighting recent innovations in gasification, pyrolysis, and incineration methods. It is also a timely review due to the urgent need for sustainable waste management solutions amidst growing environmental concerns and stringent regulations on tyre disposal. Highlights: • Thermochemical innovation — exploring cutting-edge gasification, pyrolysis, and incineration for recycling end-of-life tyres. • Product analysis — examining oil, gas, and char, evaluating their efficiency and environmental impact. • Optimal conditions — identifying the key factors that influence optimal yield and quality in tyre recycling processes. [ABSTRACT FROM AUTHOR]

Background: Accurate prediction of compound-protein interaction (CPI) plays a crucial role in drug discovery. Existing data-driven methods aim to learn from the chemical structures of compounds and proteins yet ignore the conceptual knowledge that is the interrelationships among the fundamental elements in the biomedical knowledge graph (KG). Knowledge graphs provide a comprehensive view of entities and relationships beyond individual compounds and proteins. They encompass a wealth of information like pathways, diseases, and biological processes, offering a richer context for CPI prediction. This contextual information can be used to identify indirect interactions, infer potential relationships, and improve prediction accuracy. In real-world applications, the prevalence of knowledge-missing compounds and proteins is a critical barrier for injecting knowledge into data-driven models. Results: Here, we propose BEACON, a data and knowledge dual-driven framework that bridges chemical structure and conceptual knowledge for CPI prediction. The proposed BEACON learns the consistent representations by maximizing the mutual information between chemical structure and conceptual knowledge and predicts the missing representations by minimizing their conditional entropy. BEACON achieves state-of-the-art performance on multiple datasets compared to competing methods, notably with 5.1% and 6.6% performance gain on the BIOSNAP and DrugBank datasets, respectively. Moreover, BEACON is the only approach capable of effectively predicting knowledge representations for knowledge-lacking compounds and proteins. Conclusions: Overall, our work provides a general approach for directly injecting conceptual knowledge to enhance the performance of CPI prediction. [ABSTRACT FROM AUTHOR]

Oxybutynin (Ditropan), a widely distributed muscarinic antagonist for treating the overactive bladder, has been awaiting a definitive crystal structure for ≈50 years due to the sample and technique limitations. Past reports used powder X‐ray diffraction (PXRD) to shed light on the possible packing of the molecule however their model showed some inconsistencies when compared with the 2D chemical structure. These are largely attributed to X‐ray‐induced photoreduction. Here microcrystal electron diffraction (MicroED) is used to successfully unveil the experimental 3D structure of oxybutynin hydrochloride showing marked improvement over the reported PXRD structure. Using the improved model, molecular docking is applied to investigate the binding mechanism between M3 muscarinic receptor (M3R) and (R)‐oxybutynin, revealing essential contacts/residues and conformational changes within the protein pocket. A possible universal conformation is proposed for M3R antagonists, which is valuable for future drug development and optimization. This study underscores the immense potential of MicroED as a complementary technique for elucidating unknown pharmaceutical structures, as well as for protein‐drug interactions. [ABSTRACT FROM AUTHOR]

Background: The main aim of the current study is to develop, synthesize, in silico, in vitro and in vivo potentials of N-[5-(1,3,4,5-tetrahydroxycyclohexyl)-1,3,4-thiadiazole-2-yl] benzamide derivatives for a possible anticancer drug to improve their efficiency and selectivity against cancer cells, computational approaches aided in the rational design of these chemicals. Spectroscopic methods verified the chemical structures of the target compounds. The structures of the synthesized analogs were determined by elemental analysis, IR, 1H NMR, 13C NMR and MS. Structure shows the presence of 1,3,4, thiadiazole also responsible for anticancer activity. The 10 analogs were synthesized and showed encouraging anticancer efficacy in preliminary biological evaluation, suggesting they might be suitable lead candidates for more optimization and preclinical exploration. Result: N-[5-(1,3,4,5-tetrahydroxycyclohexyl)-1,3,4-thiadiazole-2-yl] benzamide derivatives were synthesized (5a-5j) showed an optimum IC50 value in in vitro activity by SRB assay using MCF-7 as a strain, and the few selected analogs 5b,5 g & 5 h were subjected for in vivo anticancer activity by DMBA induction of tumors in mice. Conclusion: Through a computational and experimental approach, this study results a way for newer derivatives for the class of anticancer drugs. [ABSTRACT FROM AUTHOR]

The utilization of biologically active metal complexes in medicine is gaining recognition as an alternative approach to traditional biologically active organic molecules, which often exhibit undesirable side effects. This study focuses on the synthesis and characterization of a Co(II) complex derived from the (E)‐2‐((2‐hydroxybenzylidene)amino)‐5‐methylbenzonitrile ligand system (HL) and cobalt(II) acetate tetrahydrate in a dichloromethane/methanol solution. A comprehensive characterization strategy was employed, involving proton and carbon nuclear magnetic resonance, infrared, electronic spectra, PXRD, SEM‐EDX, and mass spectroscopies, as well as elemental analysis (CHN and Co), TGA, and molar conductance, to confirm the chemical structures of the ligand and its complex. The infrared spectral data revealed the ligand as a bidentate ligand, chelating the Co(II) ion through the oxygen and nitrogen atoms of the phenolate and imine groups. Additionally, PXRD and SEM analyses indicated crystalline and amorphous properties for the ligand and complex, respectively. Assessment of antimicrobial potential using a modified disc diffusion method, with streptomycin as the positive control, demonstrated the complex's enhanced antibacterial activity compared to the ligand against all tested bacteria, showing a concentration‐dependent response. Similarly, antioxidant studies revealed promising results, with the complex exhibiting superior DPPH radical scavenging activity (IC50 values: ligand 64.5 μg.mL−1, complex 43.1 μg.mL−1). Theoretical analysis through DFT calculations and molecular docking provided insights into the electronic properties and binding affinity of the ligand and complex, supporting the experimental findings and affirming the biological activities exhibited by the compounds. Overall, this research showcases the synthesis, characterization, and biological evaluation of a promising Co(II) complex, highlighting its potential as an effective antimicrobial and antioxidant agent. [ABSTRACT FROM AUTHOR]

Cancer is prevailing around the world and so does its mortality rates. Conventionally used therapies have some adverse effects as they are not entirely accurate, leading researchers and investigators to explore new ways and materials. They are constantly looking into ways that can effectively cure this malicious disease and in this effort, they came across new smart materials labeled as nanoparticles (NPs). In between various sorts of nanoparticles, only graphene‐based nanomaterials (GBNMs) shine because of their particular chemical structure and properties. They have high drug loading capacity, can easily target specific tissues, and can be easily functionalized according to the stage and other factors for a patient. Several researches and trials have been executed on animal models to check the potency of these nanoparticles proving them revolutionary in the medical domain, especially for combating cancer. Through this review, we evaluate the experiments conducted by scientists in an effort to devise a platform based on graphene nanoparticles for curing cancer efficiently by using single or multiple therapeutic approaches. [ABSTRACT FROM AUTHOR]

Porous polymer show great potential for CO2 capture owing to its high specific surface area, adjustable porous structure and chemical structure. Herein, a novel CO2 adsorption materials ALP−M (M: Cu2+, Mg2+, Ni2+) were prepared through coordination between azo‐linked porous polymer (ALP) synthesized by oxidative coupling polymerization of tris(4‐aminophenyl)amine and metal ions. The structures and morphology of as‐prepared materials were demonstrated by FT‐IR, XRD, XPS, BET and SEM, the CO2 capture performance and mechanism of ALP−M were also investigated through static adsorption and column adsorption experments, the results show that metal ions can enhance the CO2 adsorption and desorption performance of ALPs by coordination adsorption. ALP−M showed a highest static CO2 adsorption capacity of 2.67 mmol g−1 at 273 K (1 bar), which is 35.5 % higher than that of ALP. The metal ions served as Lewis acid sites can enhance the affinity of adsorbent for CO2. In column adsorption experiments, the ALP−M showed a higher saturated adsorption capacity 4.99 mmol g−1 at 273 K (1 bar) than that of static adsorption, and excellent cycling stability after 500 adsorption and desorption cycles, the adsorption capacity retention rate of ALP−M for CO2 can reach 98 %. [ABSTRACT FROM AUTHOR]

In recent years, nitrogen‐based ruthenium complexes have become an important material for dye‐sensitized solar cells and photo‐catalytic H2O and CO2 reduction research and applications, thanks to their charge transfer feature from the metal to the ligand. The electronic and spectral properties of such materials can be easily modified by changing the substituents and ligands. In this study, a new ruthenium (II) complex with N‐functionalized pyrrole derivative ([Ru(bpy)2(bpyCONHArPy)]+2 complex) was successfully synthesized and characterized. Its optical and electrochemical properties were studied by means of fluorescence, UV‐vis spectrometry, FTIR spectroscopy and cyclic voltammetry. These results were compared with that of its components (4‐(1H‐pyrrol‐1‐yl) aniline, N4,N4′‐bis(4‐(1H‐pyrrol‐1‐yl)phenyl)‐[2,2′‐bipyridine]‐4,4′‐dicarboxamide and ligand [Ru(bpy)3]+2). Related theoretical studies were also studied to find energy levels of complex. The present work is carried out to understand what chemical changes bring when combination of all the pieces of the puzzle into a chemical structure step by step. [ABSTRACT FROM AUTHOR]

A crucial mechanism for controlling the actions of proteins is allostery. Allosteric modulators have the potential to provide many benefits compared to orthosteric ligands, such as increased selectivity and saturability of their effect. The identification of new allosteric sites presents prospects for the creation of innovative medications and enhances our comprehension of fundamental biological mechanisms. Allosteric sites are increasingly found in different protein families through various techniques, such as machine learning applications, which opens up possibilities for creating completely novel medications with a diverse variety of chemical structures. Machine learning methods, such as PASSer, exhibit limited efficacy in accurately finding allosteric binding sites when relying solely on 3D structural information. Scientific Contribution Prior to conducting feature selection for allosteric binding site identification, integration of supporting amino-acid–based information to 3D structural knowledge is advantageous. This approach can enhance performance by ensuring accuracy and robustness. Therefore, we have developed an accurate and robust model called Multimodel Ensemble Feature Selection for Allosteric Site Identification (MEF-AlloSite) after collecting 9460 relevant and diverse features from the literature to characterise pockets. The model employs an accurate and robust multimodal feature selection technique for the small training set size of only 90 proteins to improve predictive performance. This state-of-the-art technique increased the performance in allosteric binding site identification by selecting promising features from 9460 features. Also, the relationship between selected features and allosteric binding sites enlightened the understanding of complex allostery for proteins by analysing selected features. MEF-AlloSite and state-of-the-art allosteric site identification methods such as PASSer2.0 and PASSerRank have been tested on three test cases 51 times with a different split of the training set. The Student's t test and Cohen's D value have been used to evaluate the average precision and ROC AUC score distribution. On three test cases, most of the p-values ( < 0.05 ) and the majority of Cohen's D values ( > 0.5 ) showed that MEF-AlloSite's 1–6% higher mean of average precision and ROC AUC than state-of-the-art allosteric site identification methods are statistically significant. [ABSTRACT FROM AUTHOR]

Debondable pressure‐sensitive adhesives (PSAs) promise access to recyclability in microelectronics in the transition toward a circular economy. Two PSAs were synthesized from a tetravalent thiol star‐polyester forming thiol‐catechol‐connectivities (TCC) with either the biorelated DiDopa‐bisquinone (BY*Q) or the fossil‐based bisquinone A (BQA). The PSAs enable debonding by oxidation of TCC‐catechols to quinones. The extent of debonding efficiency depends on the interaction modes, which are determined by the chemical structure differences of both TCC‐motifs. BY*Q‐TCC‐PSA debonds with exceptional loss of 99 % of its approx. 2 MPa shear strength in glass‐on‐glass junctions. For BQA‐TCC‐PSA, a debonding efficiency of only approx. 60 % was found, irrespective of its initial shear strength, which could be tuned up to approx. 7 MPa. The efficiency of debonding for BY*Q‐TCC‐PSA after TCC‐oxidation is linked to the loss of synergistic interactions without strongly affecting the bulk glue properties, outperforming the purely catechol‐based BQA‐analogue. [ABSTRACT FROM AUTHOR]

Electrocatalytic carbon dioxide reduction reaction (CO2RR) is an effective way of converting CO2 into value‐added products using renewable energy, whose activity and selectivity can be in principle maneuvered by tuning the microenvironment near catalytic sites. Here, we demonstrate a strategy for tuning the microenvironment of CO2RR by learning from the natural chlorophyll and heme. Specifically, the conductive covalent organic frameworks (COFs) linked by piperazine serve as versatile supports for single‐atom catalysts (SACs), and the pendant groups modified on the COFs can be readily tailored to offer different push‐pull electronic effects for tunable microenvironment. As a result, while all the COFs exhibit high chemical structure stability under harsh conditions and good conductivity, the addition of −CH2NH2 can greatly enhance the activity and selectivity of CO2RR. As proven by experimental characterization and theoretical simulation, the electron‐donating group (−CH2NH2) not only reduces the surface work function of COF, but also improves the adsorption energy of the key intermediate *COOH, compared with the COFs with electron‐withdrawing groups (−CN, −COOH) near the active sites. This work provides insights into the microenvironment modulation of CO2RR electrocatalysts at the molecular level. [ABSTRACT FROM AUTHOR]

Electrocatalytic carbon dioxide reduction reaction (CO2RR) is an effective way of converting CO2 into value‐added products using renewable energy, whose activity and selectivity can be in principle maneuvered by tuning the microenvironment near catalytic sites. Here, we demonstrate a strategy for tuning the microenvironment of CO2RR by learning from the natural chlorophyll and heme. Specifically, the conductive covalent organic frameworks (COFs) linked by piperazine serve as versatile supports for single‐atom catalysts (SACs), and the pendant groups modified on the COFs can be readily tailored to offer different push‐pull electronic effects for tunable microenvironment. As a result, while all the COFs exhibit high chemical structure stability under harsh conditions and good conductivity, the addition of −CH2NH2 can greatly enhance the activity and selectivity of CO2RR. As proven by experimental characterization and theoretical simulation, the electron‐donating group (−CH2NH2) not only reduces the surface work function of COF, but also improves the adsorption energy of the key intermediate *COOH, compared with the COFs with electron‐withdrawing groups (−CN, −COOH) near the active sites. This work provides insights into the microenvironment modulation of CO2RR electrocatalysts at the molecular level. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) based on non-fused ring electron acceptors (NFREAs) have shown significant potential for practical application owing to their easily tunable chemical structures and short synthesis routes. The merging of side-chain engineering and terminal-group halogenation has facilitated the optimization of NFREAs properties. Thus, in this study, we developed four NFREAs using a naphthalenediimide (NDI) unit with different alkyl side-chains (–C6C10 or –C8C12) as the building block and two different electron-withdrawing groups 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile (IC) and chlorinated IC (IC-2Cl) as the terminal groups. These NFREAs were designated as NDI610-H, NDI610-Cl, NDI812-H, and NDI812-Cl, respectively. All four NFREAs exhibited similar optical bandgaps and molecular conformations. Under the synergistic effects of side-chain modification and terminal-group halogenation, the NFREAs-based active-layer morphologies were significantly different. The NDI610-Cl-based blended film demonstrated favorable phase-separation morphology, facilitating exciton dissociation and charge transport in the corresponding OSCs. Thus, the PM6:NDI610-Cl-based OSCs achieved a maximum power conversion efficiency (PCE) of 8.35%. Moreover, using D18 as the polymer donor further enhanced the device performance, with the D18:NDI610-Cl-based device yielding a higher PCE of 10.25% due to improved short-circuit current and fill factor. Our findings indicate that selecting an NDI unit as the building block and combining tailored alkyl side-chains with altered terminal groups are promising strategies for constructing highly efficient NFREAs. [ABSTRACT FROM AUTHOR]

In this article, site‐specific functionalized keratoprosthesis (KPro) was accomplished to meet epithelial on‐growth on the anterior optical surface, inhibit cell adhesion on the posterior optic surface, and promote cell ingrowth at the peripheral tissue‐haptic‐flange interface toward tissue integration. Gelatin immobilization on PC4 hydrogel surfaces was achieved through acid hydrolysis followed by EDC/NHS chemistry, and polyethylene glycol‐diacrylate (PEGDA)‐modified inter‐penetrating network (IPN) surfaces were prepared using photo‐polymerization of ethylene glycol‐diacrylate (EGDA) for enhancing and inhibiting cellular growth, respectively. The surface chemical structures of modified hydrogels were characterized using attenuated total reflectance‐infrared (ATR‐IR) spectroscopy and a bicinchoninic acid (BCA) protein adsorption assay. Further, suitable differentially functionalized surfaces were prepared and characterized using the universal testing machine (UTM), refractometer, atomic force microscopy (AFM), and contact angle measurements to understand mechanical, optical, surface morphological, and wettability properties, respectively. Finally, in vitro site‐specific cell adhesion, cell inhibition, and cell ingrowth functionalities were tested using isolated goat corneal limbal epithelial stem cells and corneal stromal fibroblast cells, respectively. Overall, the two connective articles represent a successful endeavor to develop a more esthetically pleasing, mechanically stable, tissue‐free hydrogel KPro with site‐specific surface functionality nearly mimicking the cornea's functionality. A further pre‐clinical investigation is necessary to advance this functional novel KPro to reality, especially the tissue integration aspect. [ABSTRACT FROM AUTHOR]

Sustainable synthesis of novel Calcium magnesium ferrite nanomaterial was carried out in this work using aloe vera plant extract as a fuel for the combustion method. Structural characterizations of the synthesized material shows the crystallite size∼ 14 nm with cubic structure and chemical bonds between Ca−O and Fe−O. Porous nature and agglomerated particles were observed in morphological analysis. Modified carbon paste, glassy carbon and screen printed electrodes were prepared using the synthesized nanomaterial for biomolecules sensing using cyclic voltammetry technique. Therefore, the present green synthesized CMF nanoparticles modified carbon paste electrode shows significantly high sensitivity and hence it can be used as a sensor for biomedical application. Employing the agar disc diffusion technique, the antimicrobial activity of the synthesized nanoparticles was ascertained. C against the pathogens like Pseudomonas spp., E coli, and Staphylococcus spp. [ABSTRACT FROM AUTHOR]

Fructose injection is occasionally used to dilute ademetionine 1,4-butanedisulfonate injection for patients who cannot receive glucose or sodium chloride injections in clinical settings. Since our PIVAS staff reported that discoloration occurred after ademetionine 1,4-butanedisulfonate dissolved with fructose injection, this study aims to investigate the stability of ademetionine 1,4-butanedisulfonate in fructose and glucose solutions. Ademetionine 1,4-butanedisulfonate was purchased and diluted with fructose or glucose injection for compatibility testing. The solutions were maintained under various conditions for different periods of time, after which the concentration of ademetionine 1,4-butanedisulfonate and other impurities was analyzed. The chemical structures of unknown impurities were further investigated by liquid chromatography-tandem mass spectrometry. The analytical method was validated and was deemed to be suitable for the analyses in this study. Compatibility tests indicated that ademetionine 1,4-butanedisulfonate is sensitive to temperature, illumination, and pH. When diluted with fructose or glucose, the concentration of ademetionine 1,4-butanedisulfonate decreased over time. The contents of impurities increased accordingly. Additionally, an unknown impurity was identified, speculated to be a hydroxyl oxidation product of ademetionine based on the LC-MS/MS results. Both fructose and glucose injections can be used as diluents for ademetionine 1,4-butanedisulfonate, and the resulting mixture remains stable for up to 8 h after preparation. [ABSTRACT FROM AUTHOR]

Aviation in Europe is required to use fuels containing up to 2 wt. % of sustainable aviation fuels (SAFs). A better understanding of the impact of SAFs on the combustion process will be helpful in solving problems that may arise from the widespread use of these kinds of fuels. It was assumed that the reactivity coefficient α i and the activation energy could be a criteria for assessing the impact of SAFs on the combustion process. Based on DGEN engine tests, the following activation energy values of C O 2 and C O formation reactions were obtained—Jet A-1: E a C O 2 / R = 3480 and E a C O / R = 982 ; A30: E a C O 2 / R = 3705 and E a C O / R = 2903 ; and H30: E a C O 2 / R = 3637 and E a C O / R = 2843 . These results indicate differences in the structure of combustion reaction chains involved by the SAF addition to Jet A-1 fuel. The same conclusion has been formulated on the basis of the reactivity coefficient αi. The values of maximum cylinder pressure (Pmax) obtained during indicator RCCM (rapid compression combustion machine) tests correlated with both the activation energy and coefficients of reactivity. This suggests that the influence of SAF addition to Jet A-1 fuel on the structure of chemical reactions chain during RCCM tests is similar to the influence during DGEN 380 tests. The assumption stated above was confirmed. This indicates the possibility of the preliminary forecasting of C O 2 and C O emissions from the DGEN 380 engine based on the test at the RCCM stand. [ABSTRACT FROM AUTHOR]

Activated carbons were prepared from kenaf (Hibiscus cannabinus L.). Carbonization was carried out at 600 °C for 2 h, and activation was performed using air at 600 °C and using CO2 at 750 °C. The activated carbons obtained were treated with HNO3 and H2SO4. The samples were characterized by their chemical and physical structure. The activated carbons obtained were mainly macroporous, and their structure underwent major changes with the activation method and acid treatment. Activated carbons were alkaline and acid-treated carbons were neutral. They were used for phenol adsorption and a kinetic and mechanistic study of adsorption was carried out. The fit to the pseudo-second order and Elovich models was predominant. The rate-limiting step of the process was determined to be diffusion within the pores, as the experimental data fit the Bangham model. DFT simulation showed that the preferred adsorption position involves π-π stacking and that oxidation enhances this interaction. Furthermore, the simulation showed that the interaction of phenol with oxygenated functional groups depends on the type of functional group. [ABSTRACT FROM AUTHOR]

This study introduces a deep learning framework based on SMILES representations of chemical structures to predict drug–drug interactions (DDIs). The model extracts Morgan fingerprints and key molecular descriptors, transforming them into raw graphical features for input into a modified ResNet18 architecture. The deep residual network, enhanced with regularization techniques, efficiently addresses training issues such as gradient vanishing and exploding, resulting in superior predictive performance. Experimental results show that StructNet-DDI achieved an AUC of 99.7%, an accuracy of 94.4%, and an AUPR of 99.9%, demonstrating the model's effectiveness and reliability. These findings highlight that StructNet-DDI can effectively extract crucial features from molecular structures, offering a simple yet robust tool for DDI prediction. [ABSTRACT FROM AUTHOR]