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The cube‐like copper ferrite (CuFe2O4) nanocrystallines are produced by the hydrothermal method without using any surfactant. X‐ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT‐IR) are used to characterize the morphology, structure, and phase of the samples. CuFe2O4 nanocubes show the superior catalytic performance of reduction 4‐nitrophenol (4‐NP) to 4‐aminophenol (4‐AP). 20 mg CuFe2O4 nanocubes can totally convert 4‐NP to 4‐AP in 30 s at room temperature. Moreover, the reaction kinetics of 4‐NP catalytic reduction are also studied. Hence, this innovative CuFe2O4 nanocube has a lot of potential for organic pollutant destruction. [ABSTRACT FROM AUTHOR]

Catalytic reduction of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) is an important method for treating toxic nitroaromatic pollutant. In this work, amorphous CoSn(OH)6 nanocubes were synthesized by coprecipitation and calcination methods for 4-NP photocatalytic reduction. The crystal structure, morphology and optical property of the samples were characterized by XRD, SEM, TEM, XPS, and UV–vis DRS. The amorphous CoSn(OH)6 nanocubes showed excellent photocatalytic performance in 4-NP reduction. The effects of catalyst dosage, 4-NP concentration, and sodium borohydride concentration on the conversion rate of 4-NP were investigated. The results showed that the conversion rate of 4-NP could reach 98.38% in 15 min at room temperature under visible light irradiation. After five cycles of experiments, the conversion rate of 4-NP remained above 90%, indicating the good catalytic stability of the amorphous CoSn(OH)6 nanocubes. Finally, the mechanisms of photocatalytic reduction on amorphous CoSn(OH)6 nanocubes are also discussed. The successful preparation of amorphous CoSn(OH)6 nanocubes may enable the widespread use of amorphous polymetallic oxides for the removal of nitrophenols from wastewater in the future. Highlights: Amorphous CoSn(OH)6 nanocubes were synthesized without using any surfactant after calcining in argon at 300 °C; Amorphous CoSn(OH)6 nanocubes show the narrower bandgap than that of CoSn(OH)6 nanocrystals. Amorphous CoSn(OH)6 nanocubes exhibit superior photocatalytic reduction 4-NP to 4-AP performance. [ABSTRACT FROM AUTHOR]

Ginseng rusty root symptoms (GRS) is a primary disease of ginseng, which seriously decreases the yield and quality of ginseng and causes enormous losses to ginseng production. GRS prevention and control is still challenging due to its unclear etiology. In this study, the phloem tissue of healthy Panax ginseng (AG), the nonred tissue of the phloem epidermis around the lesion (BG), and the red lesion site tissue of GRS (CG) were extracted for mRNA transcriptomic analysis; 35,958 differentially expressed genes (DEGs) were identified and were associated with multiple stress resistance pathways, reactive oxygen species (ROS), and iron ion binding. Further study showed that the contents of O2•‐, H2O2, and malondialdehyde (MDA) were significantly increased in BG and CG tissues. Under anaerobic conditions caused by excessive soil moisture, the overproduction of ROS destroys cell membranes, simultaneously converting Fe2+ to Fe3+ and depositing it in the cell wall, which results in GRS, as evidenced by the success of the GRS induction test. [ABSTRACT FROM AUTHOR]

The problem of robust, angular velocity-free control and fault-tolerant control for liquid-filled flexible spacecraft attitude maneuver subject to unknown external disturbances is investigated. Moreover, state variables measurement uncertainty and actuator failures are explored. The liquid sloshing effect of spacecraft fuel is equivalent to a two-order spring-mass model, and the flexible attachments are equivalent to the Euler–Bernoulli beams. The external disturbance, multiple failures of the output actuator, and the coupled interference caused by liquid sloshing and vibrations of flexible attachments are distinguished as continuous and percussive disturbances. First, a fault-tolerant control method against the percussive disturbances is proposed, and the robustness performance and characteristics of this method are analyzed. Then, both continuous and percussive disturbances are considered to propose a new fault-tolerant control method based on a nonlinear disturbance observer, which is used to estimate the integrated disturbance. The Lyapunov stability theory proves that the proposed control strategy can make the state variables converge to a small neighborhood of the origin in finite time. Finally, the numerical simulation is used to verify the effectiveness and robustness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

Currently, the predominant thermal insulation materials in the construction industry are primarily derived from inorganic sources. While these materials demonstrate commendable thermal insulation capabilities, their widespread use raises significant environmental concerns. The utilization of wood fiber materials presents a promising solution to mitigate these drawbacks. This study focuses on the fabrication of biodegradable fiber insulation board (BFIB) using camphor branches. The manufacturing process avoids the use of chemical additives, employing a physical method that utilizes hot pressing and relies on the formation of intermolecular hydrogen and hydroxide bonds between the fibers. The study evaluates the influence of applied pressure on the properties of BFIB. SEM images reveal that, with an increase in applied pressure, the fibers exhibit a more regular pattern, subsequently enhancing the mechanical properties, hygric behavior, and fire resistance properties of BFIB. As an environmentally friendly and renewable material, BFIB holds the potential to substitute conventional insulation materials. It is particularly intriguing for energy-saving purposes when applied as building insulation for walls or ceilings. [ABSTRACT FROM AUTHOR]

The axial buckling load of single carbon fiber or composite strands is typically predicted using Euler's formula, developed for isotropic materials. This study introduces anisotropy in a mechanical carbon/epoxy Z‐pin model under axial pressure. It examines the influence of compressive modulus, shear modulus, off‐axis angle, and aspect ratio on its buckling behavior. Results show that the axial instability performance of the Z‐pin decreases with lower compression, shear modulus, and aspect ratio while keeping the tensile modulus fixed. Anisotropy decreases buckling load by up to 14% compared with Euler's formula, which only considers tensile modulus. Additionally, the impact of the deflection Angle between the pressure and pin‐axis can be ignored when it is less than 3°. Highlights: Euler formula overestimates composite Z‐pin buckling force under axial pressure.Anisotropy decreases buckling load by up to 14% for carbon/epoxy.Shear modulus is more influential on Z‐pin with a small aspect ratio.For off‐axial compression angles <3°, influence can be ignored. [ABSTRACT FROM AUTHOR]

The performance of fiber‐reinforced composites is not only determined by their constituents, but also by the spatial distribution of inclusions. The traditional random distribution algorithm only considers the randomness of its relative position, and every newly generated fiber has to be checked with all the existing fibers, which requires a large amount of calculation. In this paper, inspired by the spreading process that the fibers are not arranged randomly, but the forces acting on the upper and lower rows of fibers. A random fiber distribution algorithm based on partition randomness is proposed, and a microscopic model of in‐plane fibers with random distribution is established. The maximum volume fraction of fibers generated by the algorithm is 75%, and the generation time is less than 20s. Statistical characterization and finite element analysis of the structure generated by the algorithm are compared with the experimental data to verify the randomness and effectiveness of fibers. The algorithm overcomes the jamming limit of the traditional hard‐core method, and can efficiently generate random microstructure models with different volume fractions, which can be a promising alternative for modeling and analysis of unidirectional fiber‐reinforced composites. [ABSTRACT FROM AUTHOR]

The uncertainty of wind speed has a great impact on the reliability of wind turbines. However, previous studies usually used average wind speed or rated wind speed as inputs, ignoring the impact of time and space distribution on wind speed. Based on the hourly ground observation data of meteorological stations, four observation stations are taken as the research object of the uncertainty of wind speed spatial distribution. The four observation stations are divided into single day and one week, and seven data analysis indicators and normal distribution models are used day and night to analyze the uncertainty of wind speed time distribution. The results show that both spatial distribution and temporal distribution are important factors that cause the uncertainty of wind speed. Due to different geographical locations of four stations, their wind speed time domain diagrams are different, and the maximum wind speed, fluctuation frequency and fluctuation amplitude of wind speed at each observation station are different; The wind speed distribution of a single day is quite different from that of a week. The data of a single day and a week are analyzed by day and night, which is quite different from the overall data analysis. The necessity of wind speed uncertainty research of wind turbine considering the temporal and spatial distribution is verified, and it is concluded that normal distribution is not suitable for fitting the distribution model of four stations under study, which lays a foundation for determining the wind speed distribution model, analyzing the power characteristics of wind turbine, evaluating the generation capacity of wind turbine, and analyzing the reliability of wind turbine. [ABSTRACT FROM AUTHOR]

With the increasing installed capacity of wind turbines, ensuring the safe operation of wind turbines is of great significance. However, the failure of wind turbines is still a severe problem, especially as blade damage can cause serious harm. To detect blade damage in time and prevent the accumulation of microdamage of blades evolving into severe injury, a damage dataset based on GH Bladed simulation of blade damage is proposed. Then, based on the wavelet packet analysis theory method, the MATLAB software can automatically analyze and extract the energy characteristics of the signal to identify the damage. Finally, the GH Bladed simulation software and MATLAB software are combined for fault diagnosis analysis. The results show that the proposed method based on GH Bladed to simulate blade damage and wavelet packet analysis can extract damage characteristics and identify single-unit damage, multiple-unit damage, and different degrees of damage. This method can quickly and effectively judge the damage to wind turbine blades; it provides a basis for further research on wind turbine blade damage fault diagnosis. [ABSTRACT FROM AUTHOR]

This study concerns the importance of curing kinetic models for the prediction accuracy of the thermal overshoot in the curing process of thick polymeric composite plates. An adaptive activation energy (AAE) method was proposed to determine an accurate curing kinetic model with adaptive activation energy (CK‐AAE). Then the temperature field model of the autoclave curing process was established based on the CK‐AAE equations for predicting the curing thermal overshoot of thick polymer‐matrix composite plates. The prediction accuracy of the curing degree using the CK‐AAE model was improved greatly compared with the common curing kinetic models. And the predicted curing thermal overshoot of thick polymeric composite plates yielded good agreement with the measured results from the autoclave curing experiments. Moreover, it was observed that the curing thermal overshoot was more susceptible to the laminate thickness and less affected by the stacking sequence. [ABSTRACT FROM AUTHOR]

With rising global production and population, the globalized globe has also seen severe environmental damage. This is why renewable energy sources are important for the planet's future and human progress. In order to fight climate change and decrease emissions, promoting energy efficiency is one of the most valuable strategies. Trade patterns across borders, however, have significantly evolved. This analysis provides new evidence regarding the influence of technological progress, and more specifically, industrial innovation, on the OECD countries' international competitiveness. This article aims to analyse the effects of international commerce, FDI, and human capital on the development of renewable energy sources, energy efficiency measures, and cutting-edge technologies. In this analysis, we look at how different variables, including GDP per capita, trade, FDI, human capital, and urbanization, affect one another. To conduct the analysis, researchers used a pool of annual time series data from 2000 to 2019 for OECD economies. The long-term relationship between the variables is estimated using the AMG estimation, Cup-FM, and Cup-BC test. AMG estimation, Cup-FM estimation, and Cup-BC estimation were all used, providing valid results for the investigation. Research shows that energy efficiency, renewable energy, and technological innovation are negatively affected by FDI and urbanization but positively affected by GDP per capita, trade, and human capital. There is no statistically significant effect of human capital on the dependent variables. The estimated results also provide important policy consequences for the chosen and the other emerging economies in creating an adequate route ahead to sustainable development. [ABSTRACT FROM AUTHOR]

Onshore wind turbines are primarily installed in high-altitude areas with good wind energy resources. However, in winter, the blades are easy to ice, which will seriously impact their aerodynamic performance, as well as the power and service life of the wind turbine. Therefore, it is of great practical significance to predict wind turbine blade icing in advance and take measures to eliminate the adverse effects of icing. Along these lines, three approaches to supervisory control and data acquisition (SCADA) data feature selection were summarized in this work. The problems of imbalance between positive and negative sample datasets, the underutilization of SCADA data time series information, the scarcity of high-quality labeled data, and weak model generalization capabilities faced by data-driven approaches in wind turbine blade icing detection, were reviewed. Finally, some future trends in data-driven approaches were discussed. Our work provides guidance for the use of technical means in the actual detection of wind turbine blades. In addition, it also gives some insights to the further research of fault diagnosis technology. [ABSTRACT FROM AUTHOR]

Cuticle is not only critical for protecting insects from noxious stimuli but is also involved in a variety of metabolic activities. Cuticular proteins (CPs) affect cuticle structure and mechanical properties during insect growth, reproduction, and environmental adaptation. Here, we describe the identification and characterization of a member of the RR‐1 subfamily of CPs with an R&R consensus (CPR) in Tribolium castaneum (TcCPR69). Although it was previously reported to be highly expressed in the wings, we found that knocking down TcCPR69 by RNA interference (RNAi) did not cause obvious wing abnormalities but markedly disrupted the growth and metamorphosis of beetles with 100% cumulative mortality; additionally, the chitin content of the pharate adult was decreased and the new abdominal cuticle was significantly thinner before molting. TcCPR69 showed chitin‐binding ability and the expression levels of key genes involved in chitin metabolism (trehalase [TcTRE], chitin synthase [TcCHSA and TcCHSB], and chitinase [TcCHT5 and TcCHT10]) were also decreased by TcCPR69 knockdown. TcCPR69 gene expression peaked shortly after molting and was increased 2.61 fold at 12 h after 20‐hydroxyecdysone (20E) injection. This was reversed by RNAi of the ecdysone‐related genes ecdysone receptor (TcECR) and fushi tarazu transcription factor 1 (TcFTZ‐F1). These results indicate that TcCPR69 is positively regulated by 20E signaling to contribute to cuticle formation and maintain chitin accumulation during the growth and metamorphosis of beetles. [ABSTRACT FROM AUTHOR]