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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/SnS2 heterojunction photocatalyst is successfully designed and fabricated using a hydrothermal method and photodeposition process for photocatalytic tetracycline (TC) degradation. The optimal Pt/SnS2 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 SnS2, 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 SnS2, 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. [ABSTRACT FROM AUTHOR]

Thermoplastic nonwoven composites were produced with the air‐laying and foam‐forming processes from cellulosic and plastic fibers. The two raw material combinations were (1) PP/PE (fiber length 3 mm), PP/PE (12 mm), fluff pulp fibers (2 mm) and (2) PP/PE (3 mm), fluff pulp fibers, viscose (10 mm). After forming, the fibrous sheets (400 gsm) were bonded with heat pressing (145°C). The effect of the carrier medium, air or aqueous foam, on the tensile and impact properties and sheet structure was explored. The air‐laids differed from the foam‐laids by sheet anisotropy, density, and the lack of an additional bonding regime between wood fibers due to the dry forming process. The PP/PE bonding fibers gave the air‐laids a good capacity to elongate compared to the foam‐laids. The advantage was lost when nonbonding viscose was added. The impact strength was dependent on the PP/PE dosage and the sheet density, rather than the moisture‐induced bonding between wood fibers. The changing long/short fiber ratios caused gradual shifts in sheet properties, usually a reduction in a mechanical property as the share of short fiber increased in the mix. Economic analysis revealed that increasing fluff content can reduce raw material costs, providing a possibility for cost optimization in total production costs. [ABSTRACT FROM AUTHOR]

Ethyl 2-[(2-oxo-2H-chromen-6-yl)oxy]acetate, C13H12O5, a member of the pharmacologically important class of coumarins, crystallizes in the monoclinic C2/c space group in the form of sheets, within which molecules are related by inversion centers and 21 axes. Multiple C—H...O weak hydrogen-bonding interactions reinforce this pattern. The planes of these sheets are oriented in the approximate direction of the ac face diagonal. Intersheet interactions are a combination of coumarin system π–π stacking and additional C—H...O weak hydrogen bonds between ethyl acetoxy groups.

Ethyl 2-[(2-oxo-2H-chromen-6-yl)­oxy]acetate, C13H12O5, a member of the pharmacologically important class of coumarins, crystallizes in the monoclinic C2/c space group in the form of sheets, within which mol­ecules are related by inversion centers and 21 axes. Multiple C—H⋯O weak hydrogen-bonding inter­actions reinforce this pattern. The planes of these sheets are oriented in the approximate direction of the ac face diagonal. Inter­sheet inter­actions are a combination of coumarin system π–π stacking and additional C—H⋯O weak hydrogen bonds between ethyl acet­oxy groups. [ABSTRACT FROM AUTHOR]

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/SnS2 heterojunction photocatalyst is successfully designed and fabricated using a hydrothermal method and photodeposition process for photocatalytic tetracycline (TC) degradation. The optimal Pt/SnS2 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 SnS2, 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 SnS2, 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.

The photoreduction of CO2 to other products containing carbon through simulated photosynthesis is a promising area of research. However, given the complexity of the CO2 photocatalytic reduction reaction, it is crucial to adjust the structure of the photocatalysts. The focus of this study was on creating NaOH-modified Bi2WO6 nanosheet photocatalysts via a one-step hydrothermal route and using them to convert CO2 into CO through photocatalytic reduction under the condition of not using an electron sacrifice agent. The results of characterizations and activity data showed that adding an appropriate amount of NaOH significantly improved the photoreduction activity of CO2, as seen in the BWO-2 catalyst. The efficiency of photocatalysts could be improved by tuning the band structure through the addition of an appropriate amount of alkali. This adjustment improves the separation of photogenerated carriers and controls the concentration of oxygen vacancy to reduce recombination. As a result, the photocurrent activity is highly enhanced, leading to better reduction performance compared to unmodified photocatalysts. In experiments, the CO yield of the modified photocatalyst BWO-2 remained above 90 μmol/g after four trials, indicating its effectiveness in reducing CO2. This study offers insights into the regulation of band structure in bismuth-based photocatalysts for efficient CO2 reduction. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Pulp fiber airlaid nonwovens were bonded with three binder formulations in a spray and foam process. The binders were: a commercial acrylic dispersion binder, a commercial bio-containing acrylic binder; and a citric acid-carboxymethyl cellulose mixture (CACMC) (1:1 by-weight). The binder solutions were applied at same concentrations onto A4-size airlaid sheets (80 gsm) under a vacuum with 2-sided spraying and 1-sided foam coating. The sheet structure, dry and wet tensile properties, and total absorption capacity were compared. The foam application densified and bulk bonded the sheets, whereas the spray application induced surface bonding. These factors fundamentally influenced the measured sheet properties. The dry tensile strength was linearly correlated with the relatively low binder dosages. The CACMC binder exposed the differences in the binder application processes well, and lead to strong sheets with small elongation and highly application method-dependent absorption capacity compared to acrylic binders. [ABSTRACT FROM AUTHOR]

Yellow crystaline nanosheets of ZnCrO4 were synthesized by thermal assisted dissociation method at reflux temparature and at short period of time (30 Min.). XRD analysis, UV–VIS diffused reflection spectroscopy, FTIR instrumental anlalysis, fluroscence spectroscopy and SEM with EDAX techniques were utlitised for morphological characteristics of prepared composite material. The average size of ZnCrO4 nanosheets was found to be 80–100 nm, The ZnCrO4 nanosheets degraded nearly 90% methylene blue (MB) in aqueous medium of 70 min of visible light irradiation. ZnCrO4 nanosheets photocatalyzed degradation of MB in water matrices were found to be 30 times faster compare to Ag2ZrO4 while 43 times faster compared to well known P-25 titania photocatalyst. The ability of ZnCrO4 nanosheets towards the generation of radicals was studied by the scavenger study and confirmed that the hole and hydroxyl radicals are equally important for the degradation of MB dye. The cyclic stability of prepared ZnCrO4 nanosheets was thoroughly studied and found that no leaching of zinc ion in water and catalyst does not loss activity over the repeated experiments indicated its better safety and sustainability. The size of nanosheets are smaller possibly increases surface area of material and hence higher the activity.

Background: Age-related neurodegenerative diseases share a number of important pathological features, such as accumulation of misfolded proteins as amyloid oligomers and fibrils. Recent evidence suggests that soluble amyloid oligomers and not the insoluble amyloid fibrils may represent the primary pathological species of protein aggregates. Results: We have produced several monoclonal antibodies that specifically recognize prefibrillar oligomers and do not recognize amyloid fibrils, monomer or natively folded proteins. Like the polyclonal antisera, the individual monoclonals recognize generic epitopes that do not depend on a specific linear amino acid sequence, but they display distinct preferences for different subsets of prefibrillar oligomers. Immunological analysis of a number of different prefibrillar A beta oligomer preparations show that structural polymorphisms exist in A beta prefibrillar oligomers that can be distinguished on the basis of their reactivity with monoclonal antibodies. Western blot analysis demonstrates that the conformers defined by the monoclonal antibodies have distinct size distributions, indicating that oligomer structure varies with size. The different conformational types of A beta prefibrillar oligomers can serve as they serve as templates for monomer addition, indicating that they seed the conversion of A beta monomer into more prefibrillar oligomers of the same type. Conclusions: These results indicate that distinct structural variants or conformers of prefibrillar A beta oligomers exist that are capable of seeding their own replication. These conformers may be analogous to different strains of prions.

The crystal structures of hydrothermally synthesized aluminium dihydrogen arsenate(V) dihydrogen diarsenate(V), Al(H2AsO4)(H2As2O7), gallium dihydrogen arsenate(V) dihydrogen diarsenate(V), Ga(H2AsO4)(H2As2O7), and diindium bis[dihydrogen arsenate(V)] bis[dihydrogen diarsenate(V)], In2(H2AsO4)2(H2As2O7)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 M3+O6 octahedra ( M = Al, Ga, In) that are connected via one H2AsO4− and two H2As2O72− groups into chains, and further via H2As2O72− groups into layers. In Al/Ga(H2AsO4)(H2As2O7), these layers are interconnected by weak-to-medium-strong hydrogen bonds. In In2(H2AsO4)2(H2As2O7)2, the H2As2O72− 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 H2AsO4− and H2As2O72− groups. [ABSTRACT FROM AUTHOR]

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.)

A new kind of hydro-gelator antipyrine-cyclohexane carbonyl ester (substance 1) was introduced, which could gel in water at room temperature. The addition of a certain amount of water into the solution of 1 in alcohols could induce instant and in situ gelation. The organogelator combining antipyrine and methylcyclohexyl groups were obtained via organic synthesis method. The gelation properties were characterized by IR, XRD, SEM and TEM. The study shows that the compound 1 assembles into 0D vesicle with the lower content of water, while with the higher concentration, it aggregates into irregular 2D sheet structure, and gels the mixed solvents. [ABSTRACT FROM AUTHOR]

Occasional references to the relative tectonic instability of the Australian continent have been published over the last hundred years or so. Youthful tectonic forms were described from various parts of the continent throughout that period. Despite this, it was repeatedly claimed that the shield lands in particular were tectonically stable, and as recently as this century reference has been made to a concept embracing a tectonically inert continent. However, some 60 years ago, the accumulated evidence convinced E.S. Hills that in Australia all land surfaces, including the shield lands, and even recent alluvial plains, were tectonically disturbed. This conclusion was reinforced by analyses of seismicity and faulting; by regional geological mapping that revealed widely distributed tectonic forms and especially fault-related features, many of them of neotectonic age; by technological advances that allow faulting episodes to be closely dated; by the recognition of underprinting; and by the realization that many minor forms, previously unrecognized or attributed to other mechanisms or processes, are associated with crustal stress and are of tectonic origin. Thus, while Australia is a relatively stable continent, it is subject to widespread small-magnitude earth movements. Ironically, in view of earlier thinking, neotectonic forms may be better developed and preserved on the shields than elsewhere. [ABSTRACT FROM PUBLISHER]

Summary: The architecture of the heart remains controversial despite extensive effort and recent advances in imaging techniques. Several opposing and non-mutually compatible models have been proposed to explain cardiac structure, and these models, although limited, have advanced the study and understanding of heart structure, function and development. We describe key areas of similarity and difference, highlight areas of contention and point to the important limitations of these models. Recent research in animal models on the nature, geometry and interaction of cardiac sheet structure allows unification of some seemingly conflicting features of the structural models. Intriguingly, evidence points to significant inter-individual structural variability (within constrained limits) in the canine, leading to the concept of a continuum (or distribution) of cardiac structures. This variability in heart structure partly explains the ongoing debate on myocardial architecture. These developments are used to construct an integrated description of cardiac structure unifying features of fibre, sheet and band architecture that provides a basis for (i) explaining cardiac electromechanics, (ii) computational simulations of cardiac physiology and (iii) designing interventions. [Copyright &y& Elsevier]

Abstract: Self-assembly of C60-N, N′-dimethylpyrrolidinium iodide (C60-DMePyI) has been investigated in binary liquid mixtures. The C60-DMePyI molecules self-organized into nanosheets with a length of several microns and with a thickness of about 100 nm in a mixture of toluene and iodomethane. Scanning electron microscope observations indicated that a large number of nanorods having a diameter of about 20 nm were woven into the nanosheet. According to laser Raman spectroscopic and matrix assisted laser desorption ionization mass spectroscopic analyses, and X-ray diffraction study, the nanosheets involved chains of successive polyiodine units of the C60-DMePyI molecules. [Copyright &y& Elsevier]

Two new one-dimensional polymeric azido- and thiocyanato-bridged cadmium (II) complexes of 1-alkyl-2-(arylazo)imidazoles [RaaiR′ (where R = H (a), Me (b); R′ = Me (1/3/5), Et (2/4/6)] are described in this work. The 1D chain structures of these complexes have been confirmed by X-ray diffraction studies of [Cd(HaaiEt)(N3)2]n (4a) and [Cd(MeaaiEt)(SCN)2]n (6b). The azide (N3-) acts as end-on (μ-1,1; EO) and the thiocyanate (SCN-) as end-to-end (μ-1,3; EE) double bridging agents, respectively. The π–π interactions amongst inter-chain aromatic-heterocycles generate a uniform sheet. The coordination environment of the cadmium in all these complexes is distorted octahedral. The ligand, RaaiR′, is an unsymmetric N,N′-chelator and the distortion in the octahedral geometry is mainly due to the small chelate bite angle. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

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.