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Understanding and exploring the existence of a recognizable boundary between the noncovalent tetrel bond (TtB) and the coordination or weakened covalent bond are important for the bonding characterization. We have developed a simple methodology for analysing the type of bonds based on comparison of the electrostatic and total static potentials along the bond line. For the typical σ-hole noncovalent bond formed by a Tt atom in a tetrahedral molecule, we have found that the space gap between positions of the maxima of the total static potential and the negative quantity of electrostatic potential is much wider than that for the coordination bonds in a trigonal bipyramid molecular system for the Cl-Tt/Cl⋅⋅⋅Tt and N-Tt/N⋅⋅⋅Tt (Tt=C, Si, Ge) bonds in molecules and molecular complexes. The distinction between the weakened covalent and strengthened noncovalent bonds is well reflected in behaviour of the Fermi hole along the bond line. Two-factor empirical rule based on the superposition of the electrostatic and total static potentials is suggested.

Long-chain bio-based polyamide has shown promising development prospects due to its excellent properties and green renewable characteristics; however, synthesizing inherently flame-retardant long-chain bio-based polyamide remains a big challenge due to the lack of effective knowledge of the key polymerization process. Herein, intrinsicly flame-retardant long-chain bio-based polyamide 512 (PA512) was synthesized in the presence of a reactive flame retardant with high thermal stability and good water solubility. The reaction conditions and existing problems in each stage of the copolymerization system have been clarified and optimized. By utilizing a two-step pre-polymerization approach, a series of intrinsicly flame-retardant PA512 (FRPA512) with large molecular weight, high phosphorus element content and good mechanical properties were obtained. More importantly, the prepared FRPA512 with 5 wt % flame retardant loading exhibited good flame retardancy, showing a limiting oxygen index (LOI) of 28.1 % and a vertical burning rating of V-0. This study provides a feasible solution to the common problem in the synthesis of flame-retardant polyamides, while also offering new insights for future modification of polyamide copolymerization.

Light-matter strong coupling, especially Vibrational Strong Coupling (VSC), has become a significant research focus due to its potential to alter materials' inherent physical and chemical properties. Remarkably, VSC operates even in the absence of light, harnessing subtle quantum fluctuations to influence material characteristics. Vibro-polaritonic states, which are half photonic and half material, are introduced in the molecular/material energy ladder under VSC conditions. Although the underlying mechanism remains elusive, it is proposed that these hybrid states may modify chemical reactivity and other properties by altering factors such as polarity, polarizability, and Van der Waals interactions. This evolving field, vibro-polaritonic chemistry, holds vast potential for deeper exploration, particularly within molecular sciences. This Review examines VSC's observed effects on non-bonding interactions, including hydrogen bonding and π-π interactions, typically governed by dispersive forces.

The development of integrated biorefineries and the greater utilization of biomass resources to reduce dependence on fossil fuel-derived products require research emphasis not just on conversion strategies but also on improving separations associated with biorefining. A significant roadblock towards developing biorefineries is the lack of effective separation techniques evidenced by the relative deficiency of literature in this area. Additionally, high conversion yields may only be realized if effective separations generate feedstock of sufficient purity - this makes research into biomass conversion strategies all the more critical. In this review, the challenges associated with biomass separations are discussed, followed by an overview of the most appropriate separation strategies for processing biomass. One of the unit operations most appealing for biorefining, membrane separations (MS), is then considered along with a review of the recent literature utilizing this technique in biomass processing.

Amidine-substituted allosteric receptors 2 a and 2 b for benzenediols were synthesized. Receptor 2 a with five-membered amidines exhibited greater allostericity than the amide-substituted receptor 1, while 2 b with six-membered amidines exhibited less allostericity. NMR titration experiments revealed that a significant enthalpic factor was involved in the allostericity of these receptors. X-ray and DFT optimized structures of 2 a and 2 b revealed that 2 a adopted a coplanar conformation with π-conjugation between the amidines and the phenylene ring of the hydrindacene framework, resulting in high allostericity due to inactivation of the initial binding.

A series of CuCo bimetallic catalysts were prepared via the co-precipitation method for the catalytic transformation of biomass-derived 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylic acid (FDCA). FDCA acts as a precursor for biodegradable biopolymer polyethylene furanoate production, thereby achieving a carbon-neutral approach. Out of all the synthesized catalysts, CuCo(1 : 1) showed remarkable catalytic activity and yielded 70.67 % FDCA while achieving 100 % HMF conversion in 5 minutes at 50 °C temperature in the presence of tert-butyl hydroperoxide as an oxidant. Synergistic effects of the catalyst, such as adsorbed oxygen, relative oxygen vacancy, lesser pore size, and pore volume, were key factors attributed to the catalyst's excellent activity. The synthesized catalyst showed good recyclability with a minimal decrease in FDCA yield up to 5 cycles. Pre and post-characterization of catalysts such as BET, TEM, FE-SEM, XRD, H₂-TPR, CO₂ TPD, ICP-OES, and XPS were done to correlate the catalyst's properties with its activity. In addition, the effect of reaction parameters such as stirring speed, temperature reaction time, catalyst weight, base, and oxidant were studied to achieve optimum reaction conditions. The reaction products were analyzed quantitatively and qualitatively using HPLC and HR-MS.

Lattice strain engineering represents a cutting-edge approach capable of delivering enhanced performance across various applications. The lattice strain can affect the performance of electrochemical catalysts by changing the binding energy between the surface-active sites and intermediates. In this work, lattice strain is regulated through a homo/heterogeneous atomic interface merging. The strong lattice strain and electronic interactions between Ni and Mo facilitated the reaction kinetic of HER. The prepared NiMo@SSM exhibits excellent HER catalytic performance with 70 mV overpotential at the current density of 10 mA cm^-2 and long-term stability. The method of controlling lattice strain through hetero/homo atom interface merging provides a new strategy for designing high-performance alkaline HER electrocatalysts.

Molybdenum-based nanoparticles are often used as oil additives to enhance a material's tribological performance. Here, we present a highly efficient synthetic route for the bulk production of two types of MoS₂ nanostructures: multi-wall nanotubes and fullerene-like nanostructures. The presented two-step synthesis involves the transformation of ammonium heptamolybdate tetrahydrate and aniline into precursor nanowires, which are later transformed into MoS₂ through heating in a H₂S, H₂, and argon atmosphere to approximately 800 °C. Depending on the heating rate, we successfully grew MoS₂ layered compounds in various shapes and sizes. The resulting structures and compositions were characterised by X-ray powder diffraction, Raman spectroscopy, energy-dispersive X-ray spectroscopy, and electron microscopy. To assess the application potential of these MoS₂ compounds, they were dispersed in polyalphaolefin (PAO 6) oil. Improved tribological properties were observed compared to typically used transition metal dichalcogenides.

Quercetin, a natural flavonoid with antioxidant, anti-inflammatory, and anticancer properties, faces limitations in clinical application due to its poor solubility and bioavailability. This study presents a novel delivery system utilizing a combination of polyoxyethylene (100) stearyl ether and folic acid to enhance quercetin's effectiveness. We developed folate-conjugated polyoxyethylene (100) stearyl ether-coated liposomes (FA-Brij-LPs) to leverage the unique properties of polyoxyethylene (100) stearyl ether in conjunction with folic acid for targeted delivery. The FA-Brij-LPs were prepared using the thin-film hydration method and characterized for their physicochemical properties, including size, zeta potential, and drug loading capacity. The optimized FA-Brij-LPs exhibited a mean particle size of 147.57 nm, a zeta potential of 32.20 mV, and a drug loading capacity of 9.33 %. In vitro studies demonstrated sustained quercetin release and significantly enhanced cellular uptake compared to free quercetin. The Resazurin cell viability assay further revealed superior anticancer efficacy of FA-Brij-LPs. This innovative approach underscores the effectiveness of combining polyoxyethylene (100) stearyl ether with folic acid in enhancing quercetin delivery and its potential applications in cancer therapy.

5,15-bis(perfluorophenyl)-10-(4-carboxyphenyl) corrole and its Co(III), Mn(III), and Cu(III) corrole complexes were synthesized. The electrocatalytic hydrogen evolution reaction (HER) of these metal corrole complexes was investigated using different proton sources (AcOH, trifluoroacetic acid, and TsOH) in an organic dimethylformamide solvent. The electrocatalytic HER may proceed through EECC, EECEC, or EEECEC pathways (where E represents electron transfer and C represents proton binding) depending on the acidity and concentration of the proton source used. The Co corrole complex exhibits remarkable hydrogen production performance, achieving a turnover frequency of 201 s^-1 and a catalytic efficiency of 1.00. The examined metal corrole complexes also exhibit good HER activity in aqueous solution, with their catalytic activity following an order of 1-Co>1-Cu>1-Mn in both organic and aqueous phases.