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sk in diabetes and suggests new targets for disease prevention and therapy.We report the development of low-cost triboelectric nanogenerators (TENGs) based on polypropylene (PP) fabrics formulated via an inexpensive melt-blowing process with an output voltage as high as 50 V. By disinfection methods such as exposure to steam, ethanol, and dry heat at 75 °C, the commercial medical masks and N95 filtering facepiece respirators (FFRs) can be reused to fabricate PP fiber based TENGs, which provide a novel regime for energy-harvesting devices based on reusable materials. As a power source, the output of one TENG can drive 15 serially connected light-emitting diodes (LEDs) or a commercial electric calculator. PP fabric TENGs can also work as self-powered sensors for the high-sensitivity detection of mechanical impact. We provide examples where the TENG is used to detect biomechanical motion such as that associated with the extension of an elbow, the touch of a finger, the impact of footsteps, and the bending of a knee without an external power supply. Most importantly, these PP fabrics for TENGs can be obtained from decontaminated medical masks that are generated as tremendous wastes every day, which provide a great potential as sustainable energy. These properties suggest that PP fabric based TENGs are promising for harvesting energy from biological systems and that they may facilitate the large-scale production of a new range of inexpensive self-powered multifunctional wearable sensors for applications in healthcare, security, and information networks.We describe a photocatalytic system that elicits potent photoreductant activity from conventional photocatalysts by leveraging radical anion intermediates generated in situ. The combination of an isophthalonitrile photocatalyst and sodium formate promotes diverse aryl radical coupling reactions from abundant but difficult to reduce aryl chloride substrates. Mechanistic studies reveal two parallel pathways for substrate reduction both enabled by a key terminal reductant byproduct, carbon dioxide radical anion.The correlation of the rotation about the Cα-C' bond and the pyramidalization of the sp2-hybridized carbon atom C' and its three bonding partners to a flattened tetrahedron in the substructure Cβ-CαH-C'(═O)-OMe of substituted methyl acetates revealed that the two processes are not independent of each other but parts of a common molecular motion, as outlined in the preceding back-to-back paper. In the present study, we generalized the substructure to Xβ-CαH-C'(═Y)-Z with X, Y, and Z = O, N, C, and S, extending the analysis to several hundred thousand structures of the type carboxylates, carboxamides, ketones, imines, olefins, peptides, lactates, carbothioates, and phenyl derivatives, retrieved from the Cambridge Structural Database. ψ/θ Scatter plots of the individual structure points and their averaging in ψ/θav curves result in wavelike patterns with three maxima and minima and inversion symmetry at ψ = 0° and ±180 for a 360° rotation of Cβ about the Cα-C' bond. The pyramidalization of the sp2-hybridized group CαCiCoCo', which is part of the aromatic system, even disturbs the planarity of phenyl rings. Density functional theory calculations confirm the results of the CSD search.Surfactants can significantly improve the oil recovery of spontaneous imbibition (SI) in unconventional oil reservoirs, but mathematical modeling of surfactant SI for displacing oil in a tight matrix is challenging because of its complex mechanism. Considering the mechanisms of surfactant diffusion and adsorption, the flow equation for the SI of surfactant solution into an oil-saturated capillary is derived, and the dynamic capillary pressure and surfactant concentration during the SI process are characterized. https://www.selleckchem.com/products/l-kynurenine.html Then, based on the pore size distribution of the pores in a tight matrix, a core-scale mathematical model for SI of surfactant solution into an oil-saturated tight matrix is developed and validated with experimental data from the literature. The results show that surfactant adsorption can increase the product of interfacial tension and the cosine of the contact angle, and the increased capillary pressure in pores leads to a faster imbibition rate. A surfactant with a high adsorption and desorption rate on the water-solid interface and diffusion ability will lead to a higher oil production rate by SI in unconventional oil reservoirs. The proposed model is beneficial for modeling the dynamic process of surfactant SI and screening suitable surfactants for enhanced oil recovery in unconventional reservoirs.In the past, various chiral isomers accompanied by electroactive units have been distinguished using electrochemical techniques, which can produce electrochemical signals by themselves. However, it is still difficult to use an electrochemical technique to detect nonelectroactive samples. To address this bottleneck, an electroactive chiral polymer (S,S)-p-CVB-Fc that contains one redox-active ferrocene unit was designed and synthesized in this study. The electroactive polymer can give electrochemical signals as an alternative to the tested chiral samples, regardless of whether the isomers have electroactive units. Then, it was fixed on the surface of a glassy carbon electrode as an electrochemical chiral sensor. When nonelectroactive amino acids including proline, threonine, and alanine were examined by the sensor, clear discrimination in the response of peak current could be observed toward l- and d-isomers at pH 6.5. The peak current ratios (IL/ID) for proline and alanine were 1.47 and 1.48, respectively. In contrast, for threonine, the d-isomer exhibited a higher peak current than the l -isomer with a ratio of 2.59. In summary, the results ensure that the current work can enlarge the testing scope of chiral samples in the field of chiral electroanalysis using an electroactive sensor.The next generation of green insulation materials is being developed to provide safer and more sustainable alternatives to conventional materials. Bio-based cellulose nanofiber (CNF) aerogels offer excellent thermal insulation properties; however, their high flammability restricts their application. In this study, the design concept for the development of a multifunctional and non-toxic insulation material is inspired by the natural composition of seaweed, comprising both alginate and cellulose. The approach includes three steps first, CNFs were separated from alginate-rich seaweed to obtain a resource-efficient, fully bio-based, and inherently flame-retardant material; second, ice-templating, followed by freeze-drying, was employed to form an anisotropic aerogel for effective insulation; and finally, a simple crosslinking approach was applied to improve the flame-retardant behavior and stability. At a density of 0.015 g cm-3, the lightweight anisotropic aerogels displayed favorable mechanical properties, including a compressive modulus of 370 kPa, high thermal stability, low thermal conductivity (31.5 mW m-1 K-1), considerable flame retardancy (0.053 mm s-1), and self-extinguishing behavior, where the inherent characteristics were considerably improved by crosslinking. Different concentrations of the crosslinker altered the mechanical properties, while the anisotropic structure influenced the mechanical properties, combustion velocity, and to some extent thermal conductivity. Seaweed-derived aerogels possess intrinsic characteristics that could serve as a template for the future development of sustainable high-performance insulation materials.A series of β-ketoamino-based N,O-chelate half-sandwich iridium complexes with the general formula [Cp*IrClL] have been prepared in good yields. These air-insensitive iridium complexes showed desirable catalytic activity in an amide preparation under mild conditions. A number of amides with diverse substituted groups were furnished in a one-pot reaction with good-to-excellent yields through an amidation reaction of NH2OH·HCl with aldehydes in the presence of these iridium(III) precursors. The excellent catalytic activity, mild reaction conditions, and broad substrate scope gave this type of iridium catalyst potential for use in industry. All of the obtained iridium complexes were well characterized by different spectroscopy techniques. The exact molecular structure of complex 3 has been confirmed by single-crystal X-ray analysis.Gas molecules and interfaces with liquids and solids play a critical role in living organisms, sorption, catalysis, and the environment. Monitoring adsorption and heterogeneous interfaces remains difficult in experiments, and earlier models for molecular simulations lead to errors over 100% in fundamental molecular properties. We introduce conceptually new force field parameters for molecular oxygen, nitrogen, and hydrogen that reduce deviations to less then 5%. We employ a combination of a harmonic bond stretching potential and Lennard-Jones parameters with 12-6 and 9-6 options, leading to computed bond lengths, Raman peaks, liquid densities, vaporization enthalpies, and free energies of hydration in impressive agreement with experiments. Reliable free energies of hydration were obtained upon validation of density and vaporization energy without significant further parameter adjustments. We illustrate applications to O2 adsorption on Pt electrocatalysts and N2 adsorption in zeolites, showing less then 5% deviation in adsorption energies measured in experiments without additional fitting parameters. We discuss the chemical interpretation of all parameters and explain the reasons for discrepancies in earlier models. Compatibility with the Interface Force Field (IFF), CHARMM, AMBER, OPLS-AA, GROMOS, DREIDING, CVFF, PCFF, COMPASS, and QM/MM methods enables reliable simulations of gases and liquid/solid interfaces with biopolymers, minerals, and metals. The parametrization protocol can be applied to similar molecules.A highly stereoselective access to 3-sulfinyl-substituted isoindolinones has been achieved by a tandem organocatalytic addition/cyclization reaction of 2-carbobenzyloxy-N-tosylbenzylidenimine with thiols and succeeding diastereoselective oxidation with MCPBA. First, enantioenriched isoindolinone N,S-acetals have been obtained through a dynamic kinetic asymmetric transformation induced by a bifunctional chiral thiourea organocatalyst. In turn, the newly created carbon stereocenter enabled a high diastereocontrol in the subsequent sulfoxidation. Based on DFT calculations, a theoretical rationale for the stereoselectivity of the oxidation reaction is also provided.This article describes a concise synthesis of cardiotonic steroids oleandrigenin (7) and its subsequent elaboration into the natural product rhodexin B (2) from the readily available intermediate (8) that could be derived from the commercially available steroids testosterone or DHEA via three-step sequences. These studies feature an expedient installation of the β16-oxidation based on β14-hydroxyl-directed epoxidation and subsequent epoxide rearrangement. The following singlet oxygen oxidation of the C17 furan moiety provides access to oleandrigenin (7) in 12 steps (LLS) and a 3.1% overall yield from 8. The synthetic oleandrigenin (7) was successfully glycosylated with l-rhamnopyranoside-based donor 28 using a Pd(II)-catalyst, and the subsequent deprotection under acidic conditions provided cytotoxic natural product rhodexin B (2) in a 66% yield (two steps).