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The intercalation of anthracene units into polythiophene backbone can significantly regulate the discoloration properties of polymers, but the high polymerization potential leads to poor film-forming quality and properties of polymers. In order to reduce the oxidation potential of monomers containing anthracene units, a monomer 9, 10-bis (2-thiophenyl) anthracene (Th-An-Th) was synthesized by Stille coupling reaction and electrochemically polymerized in polymerization solvent BFEE, BFEE + CF3COOH, LiClO4/ACN and LiClO4/PC, respectively. The results show that th an th is difficult to copolymerize by electrochemical reaction. However, it can be a good comonomer to obtain copolymers with other monomers such as thiophene (Th), 3-methylthiophene (MeTh), 3, 4-ethylenethiophene (EDOT) and selenophone (SePh) via electrochemical copolymerization. The copolymerized films are named as P1, P2, P3 and P4. Cyclic voltammetry and FTIR tests confirm the polymerization process and the characteristic structure of the copolymers. The spectroelectrochemical test results show that the series of copolymers have rich color conversion properties. P1, P3 and P4 films can change four colors under -0.6 V to 1.0 V scanning, and show good near-infrared discoloration ability. The copolymer film has fast switching response rate and good electrochemical stability. The bleaching and coloring response times of P4 film at 521 nm are 1.9 s and 3.4 s, respectively, and the optical contrast is 35.6%. After 210 switching cycles, the optical contrast of the copolymer is only lost by 2.3%, and the electrochemical activity of the copolymer remains 82% after 400 cycles.

Chemical vapor deposition of carbon precursors on Cu‐based substrates at temperatures exceeding 1000 °C is currently a typical route for the scalable synthesis of large‐area high‐quality single‐layer graphene (SLG) films. Using molecules with higher activities than CH4 may afford lower growth temperatures that might yield fold‐ and wrinkle‐free graphene. The kinetics of growth of graphene using hydrocarbons other than CH4 are of interest to the scientific and industrial communities. We measured the growth rates of graphene islands on Cu(111) foils by using C2H2, C2H4, C2H6 and CH4, respectively (each mixed with H2). From such kinetics data we obtain the activation enthalpy (ΔH≠) of graphene growth as shown in parentheses (C2H2 (0.93±0.09 eV); C2H4 (2.05±0.19 eV); C2H6 (2.50±0.11 eV); CH4 (4.59±0.26 eV)); C2Hy (y=2, 4, 6) show similar growth behavior but CH4 is different. Computational fluid dynamics and density functional theory simulations suggest that C2Hy differs from CH4 due to different values of adsorption energy and the lifetime of relevant carbon precursors on the Cu(111) surface. Combining experimental and simulation results, we find that the rate determining step (RDS) is the dissociation of the first C−H bond of CH4 molecules in the gas phase, while the RDS using C2Hy is the first dehydrogenation of adsorbed C2Hy that happens with assistance of H atoms adsorbed on the Cu(111) surface. By using C2H2 as the carbon precursor, high‐quality single‐crystal adlayer‐free SLG films are achieved on Cu(111) foils at 900 °C. [ABSTRACT FROM AUTHOR]

The United Nations Sustainable Development Goal 4 (SDG4) indicates that education for global citizenship and appreciation of cultural diversity should be embedded at all levels of curricula. In this paper, we share findings from an analysis of curriculum documents in Victoria, Australia and Québec, Canada that identified learning related to this goal and explored the potential depth of intercultural understanding (ICU) this may lead to. While we view ICU as linking directly to the SDG4 aim of developing learners' global citizenship, we also investigated the extent to which ICU transcends the appreciation of cultural diversity or 'other' cultures. Our findings suggest that in both contexts, ICU could be categorised into three key dimensions: a focus on similarities and differences, a focus on reflection and self, and a focus on transformation. In addition, there was little evidence of interculturality beyond the cultures of immigrants. Given the history in both contexts, we identify that interculturality must also involve more inclusion of Indigenous cultures within the curriculum for all students to ensure transformative intercultural outcomes are maximised. [ABSTRACT FROM AUTHOR]

Author(s): Meihui Wang [sup.1] [sup.2] , Ming Huang [sup.1] [sup.5] , Da Luo [sup.1] , Yunqing Li [sup.1] [sup.3] , Myeonggi Choe [sup.1] [sup.3] , Won Kyung Seong [sup.1] , [...], Chemical vapour deposition of carbon-containing precursors on metal substrates is currently the most promising route for the scalable synthesis of large-area, high-quality graphene films.sup.1. However, there are usually some imperfections present in the resulting films: grain boundaries, regions with additional layers (adlayers), and wrinkles or folds, all of which can degrade the performance of graphene in various applications.sup.2-7. There have been numerous studies on ways to eliminate grain boundaries.sup.8,9 and adlayers.sup.10-12, but graphene folds have been less investigated. Here we explore the wrinkling/folding process for graphene films grown from an ethylene precursor on single-crystal Cu-Ni(111) foils. We identify a critical growth temperature (1,030 kelvin) above which folds will naturally form during the subsequent cooling process. Specifically, the compressive stress that builds up owing to thermal contraction during cooling is released by the abrupt onset of step bunching in the foil at about 1,030 kelvin, triggering the formation of graphene folds perpendicular to the step edge direction. By restricting the initial growth temperature to between 1,000 kelvin and 1,030 kelvin, we can produce large areas of single-crystal monolayer graphene films that are high-quality and fold-free. The resulting films show highly uniform transport properties: field-effect transistors prepared from these films exhibit average room-temperature carrier mobilities of around (7.0 [plus or minus] 1.0) × 10.sup.3 centimetres squared per volt per second for both holes and electrons. The process is also scalable, permitting simultaneous growth of graphene of the same quality on multiple foils stacked in parallel. After electrochemical transfer of the graphene films from the foils, the foils themselves can be reused essentially indefinitely for further graphene growth. Restricting the initial growth temperatures used for chemical vapour deposition of graphene on metal foils produces optimum conditions for growing large areas of fold-free, single-crystal graphene.

Simple Summary: Wood vinegar is a waste liquid recovered from the pyrolysis of wood to produce charcoal and a complex mixture. It is an environmentally friendly, high-quality product that can bring additional economic benefits to the plant. It is due to the diversity of its composition in agricultural practices that wood vinegar is a natural antimicrobial agent, but no study has yet investigated its antimicrobial mechanism. In this work, we evaluate the effects of wood vinegar on Escherichia coli (E. coli) in vitro, including inhibiting the growth curve of E. coli, disrupting the cellular morphology of E. coli, and crumpling E. coli cell membranes. In addition, the hypothesis that wood vinegar may inhibit biofilm formation in E. coli by suppressing the expression of malE, which in turn initiates a series of inhibitory effects, is also proposed in this study through transcriptome sequencing results. It provides a theoretical basis for the mechanism of wood vinegar as a natural antibacterial agent. To solve the problem of large-scale growth of wetland reeds, wood vinegar, a by-product of pyrolysed reed wood vinegar, can be used as a natural antimicrobial agent. In this study, we compare the changes in growth and bacterial morphology of Escherichia coli (E. coli) treated with reed wood vinegar at different pyrolysis temperatures (300 °C, 500 °C and 700 °C) and reveal the bacterial inhibition mechanism of reed wood vinegar by RNA-Seq. The results of bacteria inhibitory activity showed that 1/2MIC 500 °C wood vinegar had the most prominent bacteria inhibitory activity. qPCR results showed that reed wood vinegar was able to significantly inhibit the expression of E. coli biofilm and genes related to the cell membrane transporter proteins. Electron microscopy observed that the wood vinegar disrupted the cellular morphology of E. coli, resulting in the crumpling of E. coli cell membranes. RNA-Seq showed the multifaceted antimicrobial effects of wood vinegar and demonstrated that the inhibitory effect of wood vinegar on E. coli was mainly realized through the inhibition of the expression of malE, which is an ATP-binding cassette (ABC) transporter complex of E. coli. In conclusion, our study provides an effective method and a theoretical basis for the mechanism of reed wood vinegar as a natural antimicrobial agent and its pathway of bacterial inhibition. [ABSTRACT FROM AUTHOR]

Epitaxy is the cornerstone of semiconductor technology, enabling the fabrication of single-crystal film. Recent advancements in van der Waals (vdW) epitaxy have opened new avenues for producing wafer-scale single-crystal 2D atomic crystals. However, when it comes to molecular crystals, the overall weak vdW force means that it is a significant challenge for small molecules to form a well-ordered structure during epitaxy. Here we demonstrate that the vdW epitaxy of Sb2O3 molecular crystal, where the whole growth process is governed by vdW interactions, can be precisely controlled. The nucleation is deterministically modulated by epilayer–substrate interactions and unidirectional nuclei are realized through designing the lattice and symmetry matching between epilayer and substrate. Moreover, the growth and coalescence of nuclei as well as the layer-by-layer growth mode are kinetically realized via tackling the Schwoebel-Ehrlich barrier. Such precise control of vdW epitaxy enables the growth of single-crystal Sb2O3 molecular film with desirable thickness. Using the ultrathin highly oriented Sb2O3 film as a gate dielectric, we fabricated MoS2-based field-effect transistors that exhibit superior device performance. The results substantiate the viability of precisely managing molecule alignment in vdW epitaxy, paving the way for large-scale synthesis of single-crystal 2D molecular crystals. [ABSTRACT FROM AUTHOR]

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The existence of dead broilers in flat broiler houses poses significant challenges to large-scale and welfare-oriented broiler breeding. To ensure the timely identification and removal of dead broilers, a mobile device based on visual technology for grasping them was meticulously designed in this study. Among the multiple recognition models explored, the YOLOv6 model was selected due to its exceptional performance, attaining an impressive 86.1% accuracy in identification. This model, when integrated with a specially designed robotic arm, forms a potent combination for effectively handling the task of grasping dead broilers. Extensive experiments were conducted to validate the efficacy of the device. The results reveal that the device achieved an average grasping rate of dead broilers of 81.3%. These findings indicate that the proposed device holds great potential for practical field deployment, offering a reliable solution for the prompt identification and grasping of dead broilers, thereby enhancing the overall management and welfare of broiler populations. [ABSTRACT FROM AUTHOR]