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• A novel core–shell CM-P was prepared via a facile cation-driven electrostatic self-assembly strategy. • The charge redistribution in CM-P heterostructures was observed. • The CM-P cathodes exhibited a high specific capacity of 260 mAh/g. • The CM-P//Zn ZISCs showed a high energy density of 217.1 Wh kg−1 along with power density of 22.3 kW kg−1. Rechargeable aqueous Zn-ion hybrid supercapacitors (ZISCs) with the superiorities of high theoretical capacity, low redox potential and aqueous electrolytes with superior ionic conductivity (∼1 S cm−1) are promising energy storage systems. However, a primary concern persists due to the absence of cathode materials with both high energy densities and satisfactory cycling stability for robust ZISCs. In this study, we design a spherical core–shell covalent organic frameworks@Ti 3 CN MXene (CM-P) cathode via a cation-driven electrostatic self-assembly strategy. The CM-P with the constructed heterostructures shows both well-organized pore channels and excellent intrinsic conductivity, facilitating fast accessibility to intrinsic redox-active sites (such as C = O and N), and promoting effective ion diffusion characterized by low energy barriers. Consequently, the CM-P cathodes demonstrate excellent electrochemical performance, featuring an ultrahigh specific capacity of 260 mAh/g at 0.1 A, a high-rate capability with 68 % retention at 1 A/g, and long-term cycling stability. First-principle calculations elucidate that the enhanced charge-storage mechanism relies on the heterostructures of CM-P, accelerating ion adsorption/diffusion and electron transfer. Furthermore, the assembled CM-P//Zn ZISCs devices show a high energy density of 217.1 Wh kg−1 along with power density of 22.3 kW kg−1. This work provides an innovative approach to design COFs-based heterostructures for advanced ZISCs. [ABSTRACT FROM AUTHOR]

Aliphatic aldehydes are a class of organic compounds containing aldehyde groups, which are widespread, and closely related to people's daily life and health. In this work, a series of terpenes based hydrophobic deep eutectic solvents were designed and synthesized using hexafluoroisopropanol as hydrogen bond donor and menthol/thymol as hydrogen bond acceptor. Then they are used as extraction solvent in dispersive liquid-liquid microextraction for extracting and determining seven aliphatic aldehydes from drinking water and alcoholic beverage combined with high performance liquid chromatography-ultraviolet. Due to the fact that these hydrophobic deep eutectic solvents are liquid at the room temperature, a density greater than that of water, a lower viscosity (≤26.10 mPa s, 25 °C), after extraction and centrifugation, the microvolume DES-rich phase in the bottom is convenient for collection and direct analysis without further dissolution or dilution with organic solvents. Some factors affecting the extraction recovery were optimized by one-variable-at-a-time and response surface methodology. Under the optimal conditions, the enrichment factors for the seven aliphatic aldehydes were 48–56. The method had good performance: linear ranges of 1.0–200, 0.5–200, 0.2–200, 0.4–400, 1.0–400, 0.4–400 and 0.4–400 μg L−1 for seven aliphatic aldehydes (r 2 ≥ 0.9949), limits of detection of 0.1–0.5 μg L−1, intra-day and inter-day precisions <4.9%. The recoveries of seven aliphatic aldehydes ranged from 76.0 to 119.0%. The proposed dispersive liquid-liquid microextraction method is simple, rapid, highly efficient, and green, which effectively reduces the amount of toxic chemical reagents used and their impact on the environment. Rapid and efficient detection of aliphatic aldehydes helps ensure a healthy diet and has great application prospects in food safety analysis. [Display omitted] • Terpenes based HDESs with low viscosity and high density were designed and prepared. • A terpenes HDESs based DLLME was established for enrichment of aliphatic aldehydes. • The DES-rich phase in the bottom is easy to be collected and directly analyzed by HPLC. • The method is simple, rapid, effective and green for detecting aliphatic aldehydes. • The green profile of the method was assessed by AES and AGREE. [ABSTRACT FROM AUTHOR]

Ti 3 AlC 2 ceramic exhibits potential in Ag-based composite electrical contact materials, but its interface characteristic with Ag matrix remains unexplored. In this work, sessile drop experiment is carried out to investigate the high-temperature wetting behavior of molten Ag with Ti 3 AlC 2. Stable Ti 3 AlC 2 is hardly wetted by molten Ag below 1000 °C(contact angle of 148.5°), but the wettability of Ag/Ti 3 AlC 2 improves with the increasing temperature(final 14° at ∼1130 °C). In contrast, the Ti 3 C 2, a MXene with Al layer removed from its parent Ti 3 AlC 2 , exhibits inferior wettability with Ag(final 56.5° at ∼1130 °C). Wetting mechanism of Ag/Ti 3 AlC 2 is proposed on the basis of the interfacial structure and chemical composition. Increasing temperature accelerates dissociation of Ti 3 AlC 2 , and outward-escaping Al reacts with Ag to form interface layer with a composition of Ag 4.86 Ti 8.66 AlC 7.59 , Ag also diffuses along Ti 3 AlC 2 grain boundaries and forms gradient reactive products(Ag–Ti–Al–C), which promotes their wettability. Finally comprehensive properties of Ag/Ti 3 AlC 2 and Ag/Ti 3 C 2 are compared. Al–Ag interdiffusion slightly decreases the electrical conductivity of Ag/Ti 3 AlC 2 bulk material, but strengthen the interface bonding of composite and promote the viscosity of the molten pool, leading to the superior mechanical and anti-arc erosion properties. Absence of Al–Ag interdiffusion does remarkably improve the electrical conductivity of Ag/Ti 3 C 2 bulk materials, but lack of Al layer damages the mechanical core and wettability with Ag, resulting in a drastic decrease of anti-arco erosion property. [ABSTRACT FROM AUTHOR]

Ti 3 AlC 2 ceramic-reinforced Ag matrix composites exhibit superior electrical contact performance. However, the arc corrosion mechanism of the Ti 3 AlC 2 reinforcing phase has not been clarified; in particular, the intrinsic relationship between the microstructure and mechanical properties needs to be further explored. In this work, by combining micro/nano-indentation, microstructural and chemical composition analysis, COMSOL simulation, and accelerated aging experiments, the relationship among phase transition, microstructural evolution, and macro/micro/nano-mechanical property changes were compared and analyzed. The cycles of arc discharge produced heat accumulation, which was transmitted from the contact surface to the interior in a gradient (divided into Areas α , β , γ). Changes in the structural dissociation, oxidation, and interfacial bonding of Ti 3 AlC 2 with the Ag matrix resulted in different micro/nano-mechanical properties in these areas in terms of micro-hardness, nano-hardness, modulus, and elastic-plasticity. These findings demonstrate the key role of the phase and microstructural evolution of Ti 3 AlC 2 on the mechanical properties of such composites while also providing a mechanical theoretical basis for future structural design and interfacial optimization of eco-friendly Ti 3 AlC 2 -reinforcing phases in Ag matrix composites. [ABSTRACT FROM AUTHOR]

In addressing the challenge of ships being prone to occlusion in multi‐target situations during ship target detection, leading to missed and false detections, this paper proposes an enhanced ship detection algorithm for YOLOv7‐tiny. The proposed method incorporates several key modifications. Firstly, it introduces the Convolutional Block Attention Module in the Backbone section of the original model, emphasizing position information while attending to channel features to enhance the network's ability to extract crucial information. Secondly, it replaces standard convolution with GSConv convolution in the Neck section, preserving detailed information and reducing computational load. Subsequently, the lightweight operator Content‐Aware ReAssembly of Features is employed to replace the original nearest‐neighbour interpolation, mitigating the loss of feature information during the up‐sampling process. Finally, the localization loss function, SIOU Loss, is utilized to calculate loss, expedite training convergence, and enhance detection accuracy. The research results indicate that the precision of the improved model is 91.2%, mAP@0.5 is 94.5%, and the F1‐score is 90.7%. These values are 3.7%, 5.5%, and 4.2% higher than those of the original YOLOv7‐tiny model, respectively. The improved model effectively enhances detection accuracy. Additionally, the improved model achieves an FPS of 145.4, meeting real‐time requirements. [ABSTRACT FROM AUTHOR]

[Display omitted] • IrCo 0.13 nanoalloy is prepared by chemical reduction and electrochemical treatment. • Abundant Co vacancies and atomic heterostructure facilitate OER and HER. • Strong interaction of Ir and Co contributes to remarkable stability and activity. • IrCo 0.13 exhibits an overpotential of 238 (OER) and 18.6 mV (HER)@10 mA cm−2, respectively. • Bifunctional IrCo 0.13 as both anode and cathode displays 1.68 V@1 A cm−2 in PEMWE. Exploring the electrocatalysts with high intrinsic activity and stability for both anode and cathode to tolerate the extremely acidic condition in proton exchange membrane water electrolyzer (PEMWE) is crucial for widespread industrial application. Herein, we constructed the bifunctional IrCo x nanoalloys with abundant metal vacancies via the combination of chemical reduction and electrochemical treatment for overall water splitting. The developed IrCo 0.13 exhibits ultra-low overpotentials of 238 mV for OER and 18.6 mV for HER at 10 mA cm−2 in 0.1 M HClO 4 , and achieves the exceptional stability of 1000 h for OER and 100 h for HER at 10 mA cm−2. Further, the cell voltage is only 1.68 V to reach a high current density of 1 A cm−2 in PEMWE with IrCo 0.13 as the both cathode and anode catalytic layer, and it shows excellent corrosion resistance in acidic environment, evidenced by 415 h stable operation at 1 A cm−2. The strong electronic interactions in the Ir-Co atomic heterostructure and the in-situ generation of Co vacancies by electrochemical oxidation synergistically contribute to the enhanced activity and stability via optimizing the electronic structure of adjacent Ir active sites, enhancing the conductivity and electrochemical active surface area of the catalyst, accelerating charge transfer and kinetics. This work provides a new perspective for designing bifunctional catalysts for practical application in PEMWE. [ABSTRACT FROM AUTHOR]

Roots provide anchorage and enable the absorption of water and micronutrients from the soil for plants. Besides these essential functions, roots are increasingly being recognized as an important organ for the production of diverse secondary metabolites. The goal of this study was to investigate the chemical composition and function of terpenoid secondary metabolites in roots of different cultivars of the popular ornamental plant Chrysanthemum morifolium Ramat. Although C. morifolium is known for rich production of secondary metabolites in its flower heads and leaves, the diversity of secondary metabolites in roots remains poorly characterized. In this study, 12 cultivars of C. morifolium were selected for comparative analysis. From their roots, a total of 20 terpenoids were detected, including four monoterpenes, 15 sesquiterpenes, and one diterpene. The cultivar 'She Yang Hong Xin Ju' exhibited the highest concentration of total terpenoids at approximately 730 µg·g−1 fresh weight. Most cultivars contained sesquiterpenes as the predominant terpenoids. Of them, (E)-β-farnesene was detected in all cultivars. Based on their terpenoid composition, the 12 cultivars were planed into four groups. To gain insights into the function of root secondary metabolites, we performed bioassays to assess their effects on growth of three species of pathogenic fungi: Fusarium oxysporum, Magnaporthe oryzae, and Verticillium dahliae. Significant variability in antifungal activity of the root extracts among different cultivars were observed. The cultivar 'Xiao Huang Ju' was the only cultivar that had significant inhibitory effects on all three species of fungi. Our study reveals the diversity of terpenoids in roots of C. morifolium and their function as a chemical defense against fungi. [ABSTRACT FROM AUTHOR]

A serious problem with integrated masonry linings ladle was that the ladle wall bricks were difficult to be partially replaced. Thus, the service life of the ladle was determined by the properties of ladle wall bricks. In this study, the new generation of MgO–Al 2 O 3 –C bricks with bauxite aggregates was tested in a ladle lining of an integrated steel ladle for 103 cycles, and the corroded microstructure of the used brick was investigated. A multilayered structure of bauxite aggregates could be observed in the used brick, which inhibited the slag penetration along the boundary of the magnesia aggregates and reduced the degree of the aggregates fall off from the used bricks. Besides, during the process of slag penetration, bauxite aggregates could melt into the slag, which increased the viscosity of the slag and weakened the penetration ability of the slag. The MgO–Al 2 O 3 –C bricks with bauxite addition could improve the service life of the ladle to a certain extent. [ABSTRACT FROM AUTHOR]

Abstract The synthesis of nanoscale zero-valent iron (NZVI) with dimensions ranging from 20 to 100 nm has received tremendous attention in the control of environmental pollutants. However, due to strong magnetic attraction and van der Waals forces of NZVI, creating well-dispersed and stable NZVI particles with subnanometre size while avoiding their aggregation and retaining surface activity is a challenge. Here, for the first time, a novel Fe0@NH 2 -SiO 2 nanocomposite was prepared by making SiO 2 amino-functionalization in a simple process of hydrolysis polymerization, grafting Fe3+ on NH 2 -SiO 2 nanospheres, and reduction by sodium borohydrid. It was found that the surface of NH 2 -SiO 2 nanospheres (around 200 nm) was uniformly decorated by plentiful of well-defined Fe0 nanoparticles with a diameter of <10 nm. The as-synthesized NZVI particles exhibited some unique features, such as ultra small size and excellent dispersibility, which significantly enhanced their reactivity in the removal of pollutants from water. Compared with the unsupported NZVI, these supported Fe0 nanoparticles showed a remarkable reduction activity in the application for the removal of water pollutants, and could be recycled easily with the aid of NaBH 4. Graphical abstract Image 1 Highlights • NH 2 -SiO 2 nanospheres were successfully prepared for the first time in a facile one-step method. • NZVI particles were successfully decorated on the surface of NH 2 -SiO 2 under mild conditions. • Highly dispersed NZVI particles have ultrafine particles sizes (<10 nm). • Fe0@NH 2 -SiO 2 nanocomposite exhibits high-performance removal of water pollutants. • Fe0@NH 2 -SiO 2 can be recycled easily in the presence of NaBH 4. [ABSTRACT FROM AUTHOR]

[Display omitted] • Eruption of the rising bubbles causes the sand particles to be elutriated. • Lateral fuel injection leads to a non-uniform distribution of fluxes and gas species. • Temperature variation at z = 0.5 m leads to the sudden changes in gas thermal properties. • The HTC of sand particles ranges from 80 to 200 W/(m2·K) in the BFBG. • Sand particles have a larger Rep in the bubble phase but a smaller Rep in the dense phase. A reactive multiphase particle-in-cell approach is developed to explore the air-blown coal gasification in a bubbling fluidized bed reactor. The model is validated by comparing the predicted bed hydrodynamics and product yields with experimental data. Subsequently, the gas thermal properties and particle-scale behaviours are comprehensively explored. The results show that: (i) the density difference between two solid species gives rise to spatial segregation, which further affects the gasification process. The presence of coal feeding port causes the non-uniform distribution of bed hydrodynamics. (ii) the combustible gases species distribute above the coal feeding port. The concentration of gas species continuously increases while the gas temperature changes little in the dense region. (iii) the slip velocity of sand particles ranges from 0 to 4 m/s; the temperature ranges from 1000 K to 1150 K, and the heat transfer coefficient ranges from 80 W/(m2·K) to 200 W/(m2·K). Compared with sand, coal particles have a larger heat transfer coefficient and particle Reynolds number (Rep). Coal particles reach the maximum temperature of about 1100 K in the period of 3 s after being injected into the bed. (iv) bubble and emulsion phases give a larger Rep and smaller Rep due to the dominant role of the interphase drag force and inter-particle collision force, respectively. [ABSTRACT FROM AUTHOR]

Highly efficient and selective separation of Cr (VI) is great of importance in environmental pollution control. In this study, a novel family of hydrophobic DESs has been designed and synthesized by mixing parabens and quaternary ammonium, and then used to extract heavy metal Cr (VI) from water phase and the content of Cr (VI) is measured by 1,5-diphenylcarbazide spectrophotometry. It is found that the hydrophobic DESs exhibit excellent extraction performance towards Cr (VI). At the 1:1 M ratio of DES to Cr (VI), the extraction capacity is as high as 66.7 mg g−1, the extraction efficiency is greater than 90% for ultra-trace Cr (VI) (0.51 μg L−1), and the preconcentration factor is up to 700. When the concentration of coexisting metal ions (Cd2+, Cu2+) and organic compounds ((C 6 H 10 O 5) n , C 6 H 12 O 6 ·H 2 O) is 2000 times that of Cr (VI), the extraction efficiency is still above 90%. Compared with ionic liquid extractants, the preparation process of DES is very simple, the atomic utilization rate is 100%, and no waste is produced. These hydrophobic DESs have been used to separate and enrich Cr (VI) from actual water samples with satisfactory recoveries. The possible extraction mechanism is investigated by FT-IR and 1H NMR. Image 1 • Five kinds of novel hydrophobic deep eutectic solvents (DES) are designed and prepared for the first time. • The preparation process is simple, cheap and does not produce any waste, and the DESs themselves have low toxicity. • The hydrophobic DESs exhibit outstanding extraction performance towards Cr (VI) at both high concentration and ppb level. • Inorganic metal ions and organic compounds do not interfere with the extraction of Cr (VI). [ABSTRACT FROM AUTHOR]