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Constructing highly efficient catalysts for the degradation of organic pollutants driven by solar light in aquatic environments is a promising and green strategy. In this study, a novel hexagonal sheet-like Pt/SnS 2 heterojunction photocatalyst is successfully designed and fabricated using a hydrothermal method and photodeposition process for photocatalytic tetracycline (TC) degradation. The optimal Pt/SnS 2 hybrid behaves with excellent photocatalytic performance, with a degradation efficiency of 91.27% after 120 min, a reaction rate constant of 0.0187 min -1 , and durability, which can be attributed to (i) the formation of a metal/semiconductor interface field caused by loading Pt nanoparticles (NPs) on the surface of SnS 2 , facilitating the separation of photo-induced charge carriers; (ii) the local surface plasmon resonance (LSPR) effect of Pt NPs, extending the light absorption range; and (iii) the sheet-like structure of SnS 2 , which can shorten the transmission distance of charge carriers, thereby allowing more electrons ( e - ) and holes ( h + ) to transfer to the surface of the catalyst. This work provides new insights with the utilization of sheet-like structured materials for highly active photocatalytic TC degradation in wastewater treatment and environmental remediation.

Ethyl 2-[(2-oxo-2 H -chromen-6-yl)-oxy]acetate, C 13 H 12 O 5 , a member of the pharmacologically important class of coumarins, crystallizes in the monoclinic C 2/ c space group in the form of sheets, within which mol-ecules are related by inversion centers and 2 1 axes. Multiple C-H⋯O weak hydrogen-bonding inter-actions reinforce this pattern. The planes of these sheets are oriented in the approximate direction of the ac face diagonal. Inter-sheet inter-actions are a combination of coumarin system π-π stacking and additional C-H⋯O weak hydrogen bonds between ethyl acet-oxy groups., (© Goyal et al. 2024.)

Introduction: Oil-based emulsion solution is a common pesticide formulation in agricultural spraying, and its spray characteristics are different from that of water spraying. The well understanding of its spray characteristics is the theoretical basis to improve the pesticide spraying technology. The objective of the present study is to deepen the understanding of the spray characteristics of oil-based emulsion., Method: In this paper, the spatial distribution characteristics of spray droplets of oil-based emulsion were captured visually using the high-speed photomicrography. On the basis of image processing method, the droplet size and distribution density of spray droplets at different spatial locations were analyzed quantitatively. The effects of nozzle configuration and emulsion concentration on spray structures and droplet spatial distribution were discussed., Results: Oil-based emulsion produced a special perforation atomization mechanism compared with water spray, which led to the increase of spray droplet size and distribution density. Nozzle configuration had a significant effect on oil-based emulsion spray, with the nozzle changed from ST110-01 to ST110-03 and ST110-05; the sheet lengths increased to 18 and 28 mm, respectively, whereas the volumetric median diameters increased to 51.19% and 76.00%, respectively. With emulsion concentration increased from 0.02% to 0.1% and 0.5%, the volumetric median diameters increased to 5.17% and 14.56%, respectively., Discussion: The spray droplet size of oil-based emulsion spray can be scaled by the equivalent diameter of discharge orifice of nozzles. The products of volumetric median diameters and corresponding surface tensions were nearly constant for the oil-based emulsion spray of different emulsion concentrations. It is expected that this research could provide theoretical support for improving the spraying technology of oil-based emulsion and increasing the utilization of pesticide., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Gong, Chen, Cui, Wang, Zhang, Zhou and Liu.)

Oil-based emulsion is a common herbicide formulation in agricultural spray, and its atomization mechanism is different from that of water spray. In this paper, a theoretical model based on the characteristics of spray sheets was proposed to predict the spray droplet size for oil-based emulsion spray. An image processing method was used to measure droplet size distributions for different spray pressures and nozzle configurations, and the measured results were used to validate the theoretical model. The results show that oil-based emulsion spray is characterized by the web structure constituted by perforations. The liquid originally occupied by spray sheets eventually gathers in these web structures. The proposed theoretical model is based on the size of the nozzle exit, the angle of spray sheets, and the perforation number in the web structure, which are relatively easy to obtain. The theoretical droplet size is in inverse proportion to the square root of the perforation number in the web structure while in proportion to the square root of the area of the nozzle exit. The captured images of spray sheets and the measured droplet size distribution show consistency with the theoretical prediction. The difference between theoretical results and measured volumetric median diameter is less than 10% for different spray pressures and nozzles., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Gong, Chen and Kang.)

Waterproof-breathable (WB) materials with outstanding waterproofness, breathability, and mechanical performance are critical in diverse consumer applications. Electrospun nanofibrous membranes with thin fiber diameters, small pore sizes, and high porosity have attracted significant attention in the WB fabric field. Hot-press treatment technology can induce the formation of inter-fiber fusion structures and hence improve the waterproofness and mechanical performance. By combining electrospinning and hot-press treatment technology, polyurethane/fluorinated polyurethane/thermoplastic polyurethane/alkylsilane-functionalized graphene (PU/FPU/TPU/FG) nanofiber WB fabric was fabricated. Subsequently, the morphologies, porous structure, hydrostatic pressure, water vapor transmission rate (WVTR), and stress-strain behavior of the nanofiber WB fabric were systematically investigated. The introduction of the hydrophobic FG sheet structure and the formation of the inter-fiber fusion structure greatly improved not only the waterproofness but also the mechanical performance of the nanofiber WB fabric. The optimized PU/FPU/TPU-50/FG-1.5 WB fabric exhibited an excellent comprehensive performance: a high hydrostatic pressure of 80.4 kPa, a modest WVTR of 7.6 kg m -2 d -1 , and a robust tensile stress of 127.59 MPa, which could be used to achieve various applications. This work not only highlights the preparation of materials, but also provides a high-performance nanofiber WB fabric with huge potential application prospects in various fields.

The crystal structures of hydrothermally synthesized aluminium dihydrogen arsenate(V) dihydrogen diarsenate(V), Al(H 2 AsO 4 )(H 2 As 2 O 7 ), gallium dihydrogen arsenate(V) dihydrogen diarsenate(V), Ga(H 2 AsO 4 )(H 2 As 2 O 7 ), and diindium bis[dihydrogen arsenate(V)] bis[dihydrogen diarsenate(V)], In 2 (H 2 AsO 4 ) 2 (H 2 As 2 O 7 ) 2 , were determined from single-crystal X-ray diffraction data collected at room temperature. The first two compounds are representatives of a novel sheet structure type, whereas the third compound crystallizes in a novel framework structure. In all three structures, the basic building units are M 3+ O 6 octahedra (M = Al, Ga, In) that are connected via one H 2 AsO 4 - and two H 2 As 2 O 7 2- groups into chains, and further via H 2 As 2 O 7 2- groups into layers. In Al/Ga(H 2 AsO 4 )(H 2 As 2 O 7 ), these layers are interconnected by weak-to-medium-strong hydrogen bonds. In In 2 (H 2 AsO 4 ) 2 (H 2 As 2 O 7 ) 2 , the H 2 As 2 O 7 2- groups link the chains in three dimensions, thus creating a framework topology, which is reinforced by weak-to-medium-strong hydrogen bonds. The three title arsenates represent the first compounds containing both H 2 AsO 4 - and H 2 As 2 O 7 2- groups.

Tautomeric state of histidine is one of the factors that influence the structural and aggregation properties of amyloid β (Aβ)-peptide in neutral state. It is worth it to uncover the monomeric properties of Aβ(1-42) peptide in comparison with Aβ(1-40) peptide. Our replica-exchange molecular dynamics simulations results show that the sheet content of each tautomeric isomer in Aβ(1-42) monomer is slightly higher than that in Aβ(1-40) monomer except His6(δ)-His13(δ)-His14(δ) (δδδ) isomer, implying higher aggregation tendency in Aβ(1-42), which is in agreement with previous experimental and theoretical studies. Further analysis indicates that (εεε), (εδε), (εδδ), and (δδε) isomers prefer sheet conformation although they are in nondominating states. Particularly, it is confirmed that antiparallel β-sheets of (εδδ) were formed at K16-E22 (22.0-43.9%), N27-A30 except G29 (21.9-40.2%), and M35-I41 except G37 (24.1-43.4%). Furthermore, (εδδ) may be the easiest one to overcome structural transformation due to nonobstructing interactions between K16 and/or L17 and histidine residues. The current study will help to understand the tautomeric effect of Aβ(1-42) peptide to overcome Alzheimer's disease.