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The dependence of the performance of ultraviolet‐C (UV‐C) laser diodes on the strain relaxation of lower cladding layer (LCL) is numerically investigated. As the strain relaxation increases from 0% to 100%, the threshold current density decreases from 25 to 12.7 kA cm−2, and the slope efficiency increases from 0.039 to 0.087 W A−1, thanks to an increase in internal quantum efficiency (IQE). The improvement of IQE is mainly due to the enhanced hole injection resulting from the increased hole concentration in the distributed polarization doping layers and the reduced hole blocking barrier height of the upper waveguide layer with increasing the strain relaxation. Additionally, the effective screening of the polarization field within the quantum well ameliorates the quantum‐confined Stark effect, further improving the IQE. Our study reveals that strain relaxed LCL is imperative to achieve low‐threshold UV‐C laser diodes. [ABSTRACT FROM AUTHOR]

The three-dimensional (3D) visualization of geological structures and the dynamic simulation of geological evolutionary processes are helpful when studying the formation of renowned geological features. However, most of the existing 3D modeling software is based on raster models, which are unable to generate smooth geological boundaries. This work proposes a 3D temporally dynamic (i.e., four-dimensional (4D)) modeling method using parametric functions and vector data structures, which can dynamically build geological evolutionary vector models of well-known geological features. First, we extract the typical features of different kinds of geological formations and represent them using different parameters. Next, we select appropriate parametric functions to simulate these geological formations according to the characteristics of the individual structures. Then, we design and develop 4D vector modeling software to simulate the geological evolution of these features. Finally, we simulate an area with complex geological structures and select six real-world geological features, such as the Piqiang Fault in China and the Eye of the Sahara in the Sahara Desert, as case studies. The modeling results show that a regional geological evolutionary model that contains smooth boundaries can be established within minutes using this method. This work will support studies into the formation of renowned geological features in terms of providing visualizations and will make the representation of geological processes more intuitive in 3D. [ABSTRACT FROM AUTHOR]

Conventional wireless sensors have difficulty solving the problem of energy limitation, especially in sensor networks in hard-to-reach extreme areas. In order to solve the problem that it is difficult to charge wireless sensors in the field using conventional energy sources, the energy harvesting wireless senor is designed to use renewable energy sources for power supply. Considering the uncertainty and unknown nature of renewable energy generation, and the need for effective energy management of the sensor. In this paper, an Node Power Control Optimization (NPCO) power allocation algorithm is proposed to adjust the power allocation problem of wireless sensor nodes within each time slot. In addition, to address the unknown and random nature of energy arrival, this paper proposes a CLSTM model based on deep learning to predict the energy arrival. The continuous autonomous energy management of wireless sensor nodes is achieved by combining the CLSTM prediction results using the NPCO algorithm. The algorithm is applicable to continuous states and is able to show good performance in the verification of real solar data. The algorithm achieves better performance in terms of long-term average net bit rate compared to the current DDPG algorithm, AC algorithm, and Lyapunov optimization algorithm. [ABSTRACT FROM AUTHOR]

Groundwater flowing through a nonaqueous-phase liquid (NAPL) source zone may generate large NAPL-contaminated saturated soils and act as a long-term source of soils and groundwater contamination. Remediation efficiency and cost are greatly influenced by an accurate prediction of the thermal conductivity of NAPL-contaminated saturated soils. In this work, a series of thermal conductivity tests were carried out using a thermal probe method to investigate the influencing factors together with the prediction model. The results show that the thermal conductivity of contaminated saturated soil versus NAPL content can be divided into three stages. The variation of the thermal conductivity with NAPL content shows a slow decrease in the first stage, a significant decrease in the second stage, and a more moderate decrease in the third stage. Based on the 53 complete mineral data of soils collected from the literature, the thermal conductivity of the solid particle equation was modified. It is confirmed that quartz content is a crucial factor influencing ks and cannot be replaced by sand content. Subsequently, a new model is proposed for the prediction of the thermal conductivity of contaminated saturated soil. To improve the prediction accuracy of the model, a new normalized thermal conductivity equation (ke) and a relationship of θ and ks/kl were proposed to modify the new model. After modification, the new model can provide a well-performing prediction for the thermal conductivity of NAPL-contaminated saturated soils. [ABSTRACT FROM AUTHOR]

Nonlinear energy sinks (NESs) and tuned mass damper (TMD) have achieved excellent control performance. However, their energy and frequency robustness, as well as a large desired slide mass, impede their wide application in practice. To address this limitation, this paper proposes an asymmetric NES that combines two types of inerter NES, the AsymI-1 NES and AsymI-2 NES, to improve the damping robustness of traditional control devices and reduce the damper mass. In addition, the distinction is achieved by adding an inerter between the sliding damper and the top or bottom story. Further, the mathematical formulation of the asymmetric inerter NES is deduced. The working principle of the proposed asymmetric inerter NES is presented, and motion equations of the asymmetric inerter NES-attached system are derived. The proposed asymmetric inerter NES is optimized using impulsive excitation to analyze its energy and frequency robustness. The control performance and wavelet spectrum analyses of the asymmetric inerter NES are conducted under the action of earthquakes. The analysis results show that combining the two asymmetric inerter NESs can help to absorb seismic energy rapidly, limit structural reaction, and ensure good energetic and frequency robustness. Furthermore, the proposed asymmetric inerter NES can significantly decrease the stroke requirement and damper mass. [ABSTRACT FROM AUTHOR]

The physical and mechanical properties of coarse-grained slip zone soil are notably different from those of fine-grained slip zone soil, which is mainly composed of clay particles. Many scholars have been interested in the meso-level mechanical properties of coarse-grained slip zone soil. However, no regularity in results has been observed thus far. In this study, a series of medium-scale shear tests are conducted on slip zone soil specimens with different coarse grain contents based on a medium-scale shear apparatus. This apparatus was independently revamped and capable of real-time monitoring. The digital images of the sheared soil specimens were recorded in real time by a high-resolution camera and combined with particle image velocimetry (PIV) technology. A discrete element model involving numerical samples was established to analyze the meso- and macro-level mechanical properties. The results show that the coarse grain content (CGC) has a considerable influence on the shear deformation of slip zone soils and on the meso- and macro-level mechanical properties of the slip zone soil. Moreover, the precise thickness of the main shear band of the slip zone soil under the testing conditions was derived. The numerical sample with high CGC showed obvious dilatancy. The contact force chain network of particles is thick and complex, and the distribution range of the displacement field and the normal contact force are large. This indicates that the slip zone with a high CGC will have more significant uplift when a landslide failure occurs. This study innovatively integrated a variety of research methods, such as visual shear instrument, PIV, and discrete element numerical simulation, and provided important guidance and reference to reveal the influence of CGC on the macro-mesoscopic mechanical properties of slip zone soil and the evolution trends of landslide deformation with high CGC. [ABSTRACT FROM AUTHOR]

Deciphering the influence of nanocatalyst morphology on their catalytic activity in the oxygen evolution reaction (OER), the limiting reaction in water splitting process, is essential to develop highly active precious metal‐free catalysts, yet poorly understood. The intrinsic OER activity of Co3O4 nanocubes and spheroids is probed at the single particle level to unravel the correlation between exposed facets, (001) vs. (111), and activity. Single cubes with predominant (001) facets show higher activity than multi‐faceted spheroids. Density functional theory calculations of different terminations and reaction sites at (001) and (111) surfaces confirm the higher activity of the former, expressed in lower overpotentials. This is rationalized by a change in the active site from octahedral to tetrahedral Co and the potential‐determining step from *OH to *O for the cases with lowest overpotentials at the (001) and (111) surfaces, respectively. This approach enables the identification of highly active facets to guide shape‐selective syntheses of improved metal oxide nanocatalysts for water oxidation. [ABSTRACT FROM AUTHOR]

Aiming at the impact of the uncertainty of source load on the optimal scheduling in an integrated energy system (IES), in this paper, based on hybrid resolution modeling and hybrid instruction cycle scheduling technology, three time scales of day-ahead, intra-day rolling and real-time feedback optimization scheduling models are established, respectively, with the objectives of the economic optimal daily operation of the system, the minimum sum of the operation cost of energy purchase and wind curtailment penalty cost in the rolling control time domain, and the minimum adjustment amount of equipment output power. Then, the chaotic gravitational search algorithm (CGSA) is used to solve the problem, and the composite coordination optimization operation strategy of IES with mixed time scales based on CGSA is proposed. In the example, the comparison between the multi-timescale scheduling plan and the actual output, the comparison of the system scheduling results under different strategies and the comparison of different optimization algorithms show that the proposed optimization operation strategy is beneficial to optimize the energy flow distribution, reduce the system operation cost, improve the IES economy and optimization speed. [ABSTRACT FROM AUTHOR]

In recent years, the indoor air quality (IAQ) of educational buildings has attracted people's attention. As a resting place, the dormitory occupies more than half of the students' time in school. During sleep, the IAQ in dormitories is easily affected by breathing, which in turn affects the sleep quality and mental state of students. In order to study the relevant IAQ during sleep, this paper selected the dormitories of graduate students of different grades in a university in northern China, and monitored the temperature, humidity, CO2, PM2.5, HCHO and TVOC for two weeks during the changing seasons of autumn and winter. In addition, by issuing questionnaires, students made a subjective evaluation of the IAQ. According to the results of objective monitoring data and subjective evaluation, the IAQ changes in student dormitories of different grades, genders, and locations are statistically analyzed, and the correlation between environmental parameters is discussed. The research results show that temperature and humidity basically meet the national standards; indoor PM2.5 is positively correlated with outdoor PM2.5; and HCHO and TVOC are positively correlated with indoor temperature and humidity. Most dormitories lack natural ventilation, and the concentration of CO2 during sleep is too high, which affects the quality of sleep and mental state. [ABSTRACT FROM AUTHOR]

The microstructure characteristics of slip zone soils and the variation law of microstructural parameters during shearing are the focus of the study of landslide mechanism, which is of great importance for the study of landslide prevention and control technology. Providing satisfactory explanations at the macro view is impossible because many phenomena occur after the soil is stressed in a slip zone. At present, the microscopic and meso analyses of slip zone soils are single and emphasize the macroscopic strength and deformation characteristics of slip zone soils during shearing. This study takes the landslide on the south slope of west open-pit mine in Fushun as the research object. The mineral composition and micro-characteristics of slip zone soils were studied with an X-ray diffractometer and a scanning electron microscope. Discrete element method was used to simulate the direct shear test. The meso parameters of slip zone soils were obtained by matching the direct shear test curve. The comparative analysis of meso parameters, such as the meso displacement vector field, distribution of maximum and minimum principal stresses, contact force chain, and evolution of normal and tangential contact forces, with four groups of particle gradations under different weathering conditions was conducted. Results show that the main mineral compositions of slip zone soils are original mineral-quartz and secondary mineral-clay minerals. The content of montmorillonite in clay minerals is relatively high, reaching 43.8%. The particles of slip zone soils are mainly flakes, with compact structure, and have obvious characteristics of oriented arrangement. Slip zone soils with a low degree of weathering contain coarse particles (quartz). The shear stress-displacement curves of slip zone soils with four groups of particle gradations show a strain hardening trend. Particle gradation affects the macroscopic and microscopic geotechnical and mechanical properties of slip zone soils. The displacement zone of the displacement field after shearing under poor gradation is characterized with large particles as the boundary, and its dilatancy is pronounced under the same normal stress. When the gradation is good, the particles have contact force chain, normal direction, and shear. The distribution of directional contact force before shearing is relatively uniform, the grading of large particles is mostly poor, and the stress concentration is considerable. In the case of poor grading, the distribution range of normal and tangential contact forces after shearing is smaller than that of good grading. The distribution of contact force in the same direction angle shorter than that in the case of good grading. [ABSTRACT FROM AUTHOR]

Due to the relatively low bioavailability of tea phenolics in the small intestine, their reciprocal interaction with gut microbiota in the colon may contribute largely to their beneficial health effects. This implies that tea phenolics may be considered as prebiotics. This review summarizes the current knowledge on the metabolic fates of phenolics from green and black tea, the health benefits of tea phenolics and their microbial metabolites, and the potential underlying mechanisms. Additionally, the prebiotic effects of tea phenolics and conventional oligosaccharide prebiotics are compared. Phenolics from green tea are promptly metabolised into a series of (hydroxylated) phenylcarboxylic acids by gut microbiota, whereas lower degradation rates and metabolite yields are documented for black tea phenolics. Despite these differences, phenolics from green and black tea exhibit comparable gut microbiota modulatory effects. Moreover, intact green and black tea phenolics and their microbial metabolites provide various health benefits upon consumption, most likely due to their anti-oxidation, anti-inflammatory, gut barrier protection, and bile acid metabolism regulatory effects. Overall, the health benefits conferred by tea phenolics via modulation of gut microbiota composition and via formation of health-promoting metabolites is in many ways analogous to the prebiotic action of conventional oligosaccharides prebiotics. Therefore, we conclude that phenolics from green and black tea have the potential to be considered as prebiotics. Gaining better insights in the prebiotic effects of phenolics from green and black tea may pave the way for their high-value application in food and pharmaceutical industries. • Green & black tea phenolics exert health benefits via metabolism in the colon. • Lower metabolic rate and metabolite yields of black tea phenolics. • Similar metabolic fate and gut microbiota modulation by green & black tea phenolics. • Microbial metabolites and gut microbiota modulation beneficial for host's health. • Prebiotic effects of tea phenolics are analogous to conventional prebiotics. [ABSTRACT FROM AUTHOR]

Diglycolamides (DGAs) belong to the class of "CHON" type compounds and can form tridentate complexes with metal ions. DGA-based extractants are a subject of great interest in actinide partitioning due to their exceptionally high affinity for trivalent actinides and lanthanides. Since the separation performance of DGAs are closely related to their molecular structures, many structure-modification schemes have been proposed such as the attachment of different alkyl substituents to an amidic N atom or anchoring multiple DGA arms onto a scaffold. In this paper, literature reports that describe the effects of such modifications on the structure and performance of DGAs are summarized. By comparing the extraction and separation properties of DGA extractants with different structures, the relationship between the structure and properties of DGAs is discussed. Such work should be helpful for gaining a more comprehensive, accurate and in-depth understanding of the relationship between structure and property of DGAs to be developed. It should also be beneficial for the structural design of more new DGA extractants. [ABSTRACT FROM AUTHOR]

Deep cement mixing (DCM) piles are widely utilized for reinforcing soft clay foundations, particularly in coastal regions where soil stability is critical. Monitoring the quality and early-stage behavior of cemented soil is essential to ensure the effectiveness of DCM pile projects in meeting design requirements. Innovative methods for on-site monitoring are necessary to enhance the reliability and efficiency of these reinforcement techniques. In this study, a novel approach is proposed utilizing polymer optical fiber (POF) sensors based on physical optical sensing principles to monitor the initial hydration degree and overall quality of cemented soil during the early curing stage. The proposed method relies on the principle of physical optical sensing, where POF sensors are employed to measure changes in reflected light intensity (LI) and temperature in cemented soil. Two crucial variables, namely the initial water content and the amount of cement, are considered in analyzing their impact on the LI and temperature changes over time. Unconfined compressive strength (UCS) tests and scanning electron microscopy (SEM) analysis are conducted on cemented soil samples with varying water-cement ratios to investigate their mechanical properties and microstructure evolution. The results of the UCS tests indicate that higher initial water content prolongs the initial hydration reaction time required for cemented soil with different cement contents. Analysis of LI curves reveals a rapidly rising trend as the hydration reaction progresses, particularly evident in samples with higher initial water content. SEM analysis further demonstrates that a stable POF LI corresponds to the completion of the hydration process, with hydrated gel formation resulting in a more compact microstructure and smaller voids. The findings highlight the significant influence of cement quantity and initial water content on the mechanical strength and microstructure of cemented soil. By analyzing changes in reflected LI and temperature, the proposed monitoring method provides valuable insights into the early-stage behavior and quality of cemented soil during the curing process. This innovative use of POF sensors for on-site monitoring offers a novel approach to evaluating cemented soil in DCM pile projects. • Pioneering the combination of polymer optical fiber (POF) sensors with SEM for monitoring the hardening of early-stage cemented soil. • Establishing a robust correlation between light intensity and the evolution of soil microstructure. • Providing a potential novel and cost-effective monitoring solution for cemented soil engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] • CTC achieved a maximum of 97.8% removal in the MMT-CS bio-enhanced process. • MMT-CS promoted EPS secretion and electron transfer in the system. • The mechanism of bio-enhanced degradation of CTC by MMT-CS was revealed. • Paracoccus and Terrimonas were the key bacteria gene in MMT-CS bio-enhanced process. • The biological metabolic pathways of CTC were clarified. The efficient degradation of antibiotics holds significant implications for mitigating environmental pollution. This study synthesized a montmorillonite chitosan composite material (MMT-CS) using the gel template method. Subsequently, a bio-enhanced reactor was constructed to facilitate the degradation of chlorotetracycline (CTC). The addition of MMT-CS composite material enables the degradation of different concentrations of CTC. MMT-CS, a conductive carrier, effectively promotes microbial adhesion and boosts the metabolic activity of functional microorganisms. Additionally, it facilitates the maintenance of microbial activity under CTC pressure by promoting the secretion of extracellular polymeric substances, increasing critical enzyme activity, and enhancing the electron transfer capacity within the system. In this MMT-CS bio-enhanced process, Paracoccus (11.4%) and Bacillus (3.9%) are utilized as essential bacteria genes. The results of metabolic pathways prediction indicated significant enhancements in membrane-transport, nucleotide-metabolism, replication-repair, and lipid-metabolism. Thus, the developed self-supporting MMT-CS bio-enhanced process ensured the stability of the system during the removal of antibiotics. [ABSTRACT FROM AUTHOR]

In order to further study the structure-performance relationship of unsymmetrical diglycolamides. In this work, two types of unsymmetrical diglycolamides (Structure A: N,N'-dimethyl-N,N'-didecyl diglycoamide, LI, N,N'-dimethyl-N,N'-didodecyl diglycoamide, LIII; Structure B: N,N-dimethyl-N',N'-didecyl diglycoamide, LII, N,N-dimethyl-N',N'-didodecyl diglycoamide, LIV), which are geometrical isomers each other, were synthesized, and their extraction performances in 40/60 (v/v)% n-octanol/kerosene were studied and compared. The related results reveal that the size of the alkyl substituents attached on the amide N atoms can influence the extractant performance of the extractant, and the difference in the geometric structure of extractants can lead to the differences in their extraction performances. [ABSTRACT FROM AUTHOR]

This paper employs the Mutual Information (MI) and Back Propagation (BP) neural network model to screen the preliminarily constructed evaluation index system for carbon information disclosure (CID) quality of public companies in China's electric power sector (EPS), which is subsequently incorporated into the fuzzy comprehensive evaluation (FCE) method for evaluation application. The results show that (1) after screening, 19 out of the 31 preliminarily constructed indicators constitute an optimal index set, and (2) the evaluation application of the screened index system validates the feasibility and applicability of the index system. Simultaneously, the evaluation results reveal a generally low CID quality in the EPS. • Constructed an evaluation index system of carbon information disclosure (CID) quality for electric power sector (EPS). • The MI-BP model makes the construction of the index system rigorous and reasonable. • Conducted further screening based on the preliminary design of the index system. • The index system exhibits strong pertinence, high correlation and low redundancy. • The evaluation results reveal a generally low CID quality in the EPS. [ABSTRACT FROM AUTHOR]

Task-oriented dialogue systems use deep reinforcement learning (DRL) to learn policies, and agent interaction with user models can help the agent enhance its generalization capacity. But user models frequently lack the language complexity of human interlocutors and contain generative errors, and their design biases can impair the agent's ability to function well in certain situations. In this paper, we incorporate an evaluator based on inverse reinforcement learning into the model to determine the quality of the dialogue of user models in order to recruit high-quality user models for training. We can successfully regulate the quality of training trajectories while maintaining their diversity by constructing a sampling environment distribution to pick high-quality user models to participate in policy learning. The evaluation on the Multiwoz dataset demonstrates that it is capable of successfully improving the dialogue agents' performance. • Domain Randomization. • User Models. • Dialogue Policy using Deep Reinforcement Learning. [ABSTRACT FROM AUTHOR]

You only look once (YOLO) target detection algorithms have garnered substantial attention in engineering inspection tasks due to their remarkable accuracy and swift detection speed. However, adapting the YOLOv7 algorithm to engineering construction presents challenges in balancing lightweight design and high precision. This work introduces a YOLOv7 lightweight detection algorithm, leveraging partial convolution to efficiently reduce network parameters without compromising detection speed. Integrating partial convolution into the network's backbone is a highly effective parameter reduction strategy. Additionally, we propose the SE_Conv module following quantitative analyses through experiments, thereby significantly enhancing the algorithm's detection accuracy. To address the impact of low-quality data on detection effectiveness in engineering tasks, the advanced bounding box loss function WIoU is employed. In a practical application scenario involving helmet detection, the algorithm achieves a notable 23.4% reduction in parameters and a substantial 28.2% decrease in operations through partial convolution. Subsequent experiments with the SE_Conv module yield a noteworthy 1.4% improvement in results. Significantly, in head detection, our algorithm surpasses YOLOv8 algorithm by 2.6% and single shot multibox detector algorithm by 9.4%. These findings underscore the efficacy of our proposed algorithm in engineering applications. [ABSTRACT FROM AUTHOR]

• RGT and SXT exhibit distinctive different sensory and volatile profiles. • A total of 12 odor-active compounds (OACs) with OAV > 1 are identified as key OACs. • Eight OACs are commonly shared between RGT and SXT, but with different contents. • The unique key OACs of RGT are (E) -linalool oxide and (Z) -jasmone. • The unique key OACs of SXT are β-cyclocitral and α-ionone. The distinctive fragrance of Wuyi Rock Tea (WRT) has garnered high attention in recent years. Herein, we conducted a comprehensive comparison of the sensory attributes and odor-active compounds (OACs) between two quintessential WRTs, namely Rougui (RGT) and Shuixian (SXT). Sensory analysis revealed that RGT exhibited a more pronounced fruity aroma, while SXT had a more complex and intricate sensory profile. By using gas chromatography-olfactory mass spectrometry (GC-O-MS) and two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF-MS) analyses, 26 OACs were identified. Among them, 12 compounds with odor activity values > 1 were recognized as key OACs. Noteworthily, eight compounds, including 6-methyl-5-hepten-2-one, 2-ethyl-3,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, linalool, methyl salicylate, geraniol, (E) -β-ionone, and (E) -nerolidol, were shared by both teas. The unique compounds for RGT were (E) -linalool oxide and (Z) -jasmone, while those for SXT were β-cyclocitral and α-ionone. These findings offer valuable insights for better understanding the flavor differences between the two most important types of WRT. [ABSTRACT FROM AUTHOR]

The effects of different solution temperatures on the microstructure and corrosion resistance of graphene nanoplatelets reinforced A380 (A380-GNPs) composites were investigated. The results show that the grain size of the composites was significantly refined by adding 0.9 wt% GNPs, and most of the Si phases in the A380-0.9 GNPs composite after solution treatment at 505 °C were spheroidal. Energy dispersive spectroscopy analysis indicated that most of the Al2Cu phases have been dissolved into the matrix. The hardness of the 505 °C solution treated composites increased by 28.8% compared to the A380-0.9 GNPs composites. Immersion corrosion tests revealed that the corrosion rate of the 505 °C solution-treated A380-0.9 GNPs composites (46.76 μg cm−2 d−1) was 24.9% lower than that of the non-solution-treated (58.41 μg cm−2 d−1). Electrochemical analyses showed that the corrosion voltage of the 505 °C solution-treated composites (− 507.41 mV) was 7.4% higher than that of the non-solution-treated (− 548.76 mV). The 505 °C solution-treated A380-0.9 GNPs composites had a high surface-area ratio between the anodic phases (α-Al) and the cathodic phases (Al2Cu, Si), and the anodic corrosion current densities were relatively weak, which resulted in the best corrosion resistance. The refinement and uniform distribution of cathodic phases, such as Al2Cu and eutectic Si, inhibit the occurrence of micro-galvanic corrosion and also reduce the corrosion rate of the composites.Graphical Abstract: The effects of different solution temperatures on the microstructure and corrosion resistance of graphene nanoplatelets reinforced A380 (A380-GNPs) composites were investigated. The results show that the grain size of the composites was significantly refined by adding 0.9 wt% GNPs, and most of the Si phases in the A380-0.9 GNPs composite after solution treatment at 505 °C were spheroidal. Energy dispersive spectroscopy analysis indicated that most of the Al2Cu phases have been dissolved into the matrix. The hardness of the 505 °C solution treated composites increased by 28.8% compared to the A380-0.9 GNPs composites. Immersion corrosion tests revealed that the corrosion rate of the 505 °C solution-treated A380-0.9 GNPs composites (46.76 μg cm−2 d−1) was 24.9% lower than that of the non-solution-treated (58.41 μg cm−2 d−1). Electrochemical analyses showed that the corrosion voltage of the 505 °C solution-treated composites (− 507.41 mV) was 7.4% higher than that of the non-solution-treated (− 548.76 mV). The 505 °C solution-treated A380-0.9 GNPs composites had a high surface-area ratio between the anodic phases (α-Al) and the cathodic phases (Al2Cu, Si), and the anodic corrosion current densities were relatively weak, which resulted in the best corrosion resistance. The refinement and uniform distribution of cathodic phases, such as Al2Cu and eutectic Si, inhibit the occurrence of micro-galvanic corrosion and also reduce the corrosion rate of the composites. [ABSTRACT FROM AUTHOR]

Macrophage autophagy plays a major role in the control and elimination of invading Mycobacterium tuberculosis. However, the function and mechanism of circRNA on macrophage autophagy in tuberculosis remain unclear. Therefore, this study aimed to explore the role of circRNA underlying macrophage autophagy in tuberculosis. Quantitative real-time polymerase chain reaction was used to detect the expression of hsa_circ_0045474, miR-582-5p and TNKS2. Autophagy was detected by LC3B immunofluorescence and transmission electron microscopy. Dual-luciferase reporter assays were used to detect the relationship of miR-582-5p and hsa_circ_0045474 or TNKS2. Western blot was used to detect the expression of LC3-І and LC3-ІІ. The results showed that hsa_circ_0045474 was down-regulated in monocytes from patients with tuberculosis and induced autophagy in macrophages. hsa_circ_0045474 sponged miR-582-5p and negatively regulated miR-582-5p expression. Overexpression of miR-582-5p affected by hsa_circ_0045474 induced autophagy in macrophages. TNKS2 served as a target of miR-582-5p and down-regulation of TNKS2 induced autophagy in macrophages regulated by miR-582-5p. In conclusion, our results demonstrated that hsa_circ_0045474 down-regulation induced macrophage autophagy in tuberculosis via miR-582-5p/ TNKS2 axis, implying a novel strategy to treat the occurrence of active pulmonary tuberculosis caused by immune escape of M. tuberculosis. [ABSTRACT FROM AUTHOR]

The macroscopic and mesolevel mechanical mechanisms of slip zone soil are a crucial subject for the research of landslide deformation evolution and slope control, but the effects of the shape and psephicity of coarse particles in a slip zone soil on the mechanical properties of the slip soil zone still need to be explored. Discrete element method (DEM) can effectively monitor and track the mesolevel mechanical parameters of geotechnical materials, such as displacement vector field, contact force chain, and particle coordination number. The rock blocks in the medium-sized shear test undergo a sophisticated process by 3D scanning technology, and a database of the blocks is established and accurately modeled by combining 3D DEM to simulate the indoor medium-sized shear test for numerical investigation in line with the test conditions. The numerical simulation results demonstrate that the psephicity and particle shape of the rock blocks significantly affect the dilatancy and mesolevel mechanical parameters of the slip zone soil specimens. In addition, the numerical models featured by poorer psephicity and more irregular particle shape display more evident dilatancy, larger particle coordination numbers, as well as better contact density inside the model. Some references for the study of the macroscopic and mesolevel mechanical mechanisms of slip zone soil are provided. [ABSTRACT FROM AUTHOR]

2D tin selenide (SnSe) is a promising semiconductive material and its thermal stability is one of the most significant evaluating indicators. However, few works are involved in the temperature‐dependent structure stability of 2D SnSe nanosheets. Herein, local structure transformation of a 2D SnSe nanosheet into SnSe2 under high temperature is characterized by a novel atomic force microscope (AFM)‐based nanoscale thermomechanical method. Based on an AFM platform, the temperature‐dependent nanomechanical properties are investigated. A softness process is found to occur upon the surface of 2D SnSe, accompanying the structure transformation under high temperature. It means that the generation of SnSe2 is due to the structure collapse of SnSe, stemming from the evaporation of Sn atoms under about 90 °C. The transformation mechanism is further verified by a real‐time nanothermomechanical method. A deeper understanding of the thermal stability and thermal decomposition mechanism of 2D SnSe is promoted. The improved in situ nanomechanical method offers a highly sensitive method to probing the nanomechanical properties of 2D materials. [ABSTRACT FROM AUTHOR]

The graphene nanoplatelets (GNPs) were used as reinforcement to fabricate the ADC12-GNPs composites via ultrasonic-assisted casting, then the composites were adopted T6 heat treatment. The microstructures and wear performance were investigated in detail. The GNPs effectively refined the α-Al grains and form a strong Al-GNPs interfacial structure with the matrix, and the T6 heat treatment further rounded the Si phases and precipitated nanoscale θ′-Al 2 Cu. With the increase of load, the wear rate increases. And with the increase of sliding velocity, the wear rate shows a tendency of decreasing and then increasing. The wear rate and COF of the ADC12-GNPs/T6 composites showed a maximum reduction of 63.3 % and 39.2 %, respectively, compared to the matrix. The self-lubrication and refinement strengthening effect of GNPs improved the wear resistance, and the interaction between nanoscale θ′-Al 2 Cu precipitates and dislocations enhanced the tribological properties. Wear morphology and three dimensional profile analysis showed that the surface roughness of the ADC12-GNPs/T6 composite was 2.73 μm, which was 150 % lower than that of the matrix (6.82 μm) when the sliding velocity was 0.28 m/s and the load was 40 N, showing typical abrasive wear characteristics. [Display omitted] • The GNPs refined the Al grains and formed a strong interfacial with the matrix. • T6 heat treatment further rounded the Si phases and precipitated nanoscale θ′-Al 2 Cu. • The wear rate of ADC12-GNPs/T6 composites was reduced by 63.3 % compared to matrix. • The wear surface roughness of ADC12-GNPs/T6 composites was reduced to 2.73 μm. [ABSTRACT FROM AUTHOR]

[Display omitted] • A catalyst of biochar in-situ enriched with cobalt tungstate and cobalt is prepared. • The BC-Co-W-700/PMS achieved 100% degradation of 20 mg/L CTC within 18 min. • BC-Co-W-700 shows high stability and applicability for CTC removal. • CoWO 4 controls the generation of oxygen vacancies and leads to the 1O 2 pathway. • Degradation mechanism is revealed using both experiments and DFT calculation. The development of low-cost, stable, and recyclable multiphase catalysts in advanced oxidation process is essential for efficient degradation of antibiotics. In this study, a BC-Co-W-700 catalyst was used to activate peroxymonosulfate (PMS) for chlortetracycline (CTC) degradation. The catalyst was prepared using reclaimed biomass material as a matrix. The biochar-based catalyst possessed abundant active sites and realized the in-situ growth of Co and CoWO 4. The BC-Co-W-700/PMS achieved 100% degradation of CTC (20 mg/L) within 18 min. Quenching and electron paramagnetic resonance experiments were conducted to investigate the reactive oxygen species (ROS) in the BC-Co-W-700/PMS system. The identified ROS in this system included 1O 2 , O 2 −, SO 4 −, and OH. Abundant ROS endowed the system with strong degradation performance, applicability, and anti-interference ability. The catalytic mechanism of BC-Co-W-700/PMS system was comprehensively investigated using a combination of electrochemical experiments and theoretical calculations. The in-situ pyrrolic N formed by biochar had a strong adsorption capacity for CTC, allowing pollutants to quickly adsorb to the catalyst surface. This greatly shortened the distance required for the catalytic reaction. The introduction of W led to abundant oxygen vacancies on BC-Co-W-700, causing the catalyst to produce a large amount of 1O 2. Furthermore, the oxygen vacancies provided a high concentration of electrons for the conversion of Co3+/Co2+. In addition, CTC degradation pathways were analyzed using density functional theory calculations, and the toxicity of the intermediates was evaluated using the quantitative structure–activity relationship combined with experiments. The green catalyst synthesis method proposed in this paper could provide a new approach for the efficient degradation of antibiotics in wastewater. [ABSTRACT FROM AUTHOR]

We propose and analyze two locking-free three-field virtual element methods for Biot's consolidation model in poroelasticity. One is a high-order scheme, and the other is a low-order scheme. For time discretization, we use the backward Euler scheme. The proposed methods are well-posed, and optimal error estimates of all the unknowns are obtained for fully discrete solutions. The generic constants in the estimates are uniformly bounded as the Lamé coefficient λ tends to infinity, and as the constrained specific storage coefficient is arbitrarily small. Therefore the methods are free of both Poisson locking and pressure oscillations. Numerical results illustrate the good performance of the methods and confirm our theoretical predictions. [ABSTRACT FROM AUTHOR]

We propose and analyze a low-order virtual element for linear elasticity problems. It can be seen as an evolution of the Bernardi–Raugel element to general polygonal meshes. Like the Bernardi–Raugel element, the local degrees of freedoms for the new virtual element are the values of two components of v at vertexes and the values of the lowest moment of normal component of v on each edge. The proposed method is well-posed, and optimal error estimates are obtained in the L 2 and H 1 norms. Moreover, the generic constants in these estimates are shown to be uniform with respect to the Lamé coefficient λ. Numerical tests are provided to illustrate the good performance of the method and confirm our theoretical predictions. [ABSTRACT FROM AUTHOR]

Duckweed is a kind of floating aquatic plant and increasing its starch production is favorable for bioenergy. In this study, we found that starch biosynthesis was greatly promoted by the supplement of nickel ion (Ni2+) through the comparison of other different ions. The starch content in duckweed was increased by nearly eightfold when duckweed was treated with 20 µM Ni2+. The analysis of paraffin sections visually found that starch granules were more complete and dark blue in Ni2+ treated duckweed than the control. Quantitative real-time PCR demonstrated that the expressions of starch synthesis-related enzymes were up-regulated in Ni2+ treated duckweed. Further analysis revealed that the accumulation of Ni2+ in duckweed effectively increased the activity of urease, which compensated for the deficiency of certain decrease in biomass and accelerated biosynthesis of the starch. Thus, our results represent another strategy to improve starch production of duckweed. [ABSTRACT FROM AUTHOR]

The thickness‐dependent nanoscale thermal behaviors of 2D SnSe nanosheets are studied via 3ω thermal mode atomic force microscopy and local Raman spectra. It is found that the 2D SnSe nanosheets demonstrate a decreasing thermal behavior with the reduction of thickness in the range of 6–40 nm. The unique thermal behavior is ascribed to the nonharmonic interlayer coupling along the armchair direction of SnSe crystal structure, in which the redshift of in‐plane vibration (Ag2, B3g) gives rise to phonon softening and finally the thickness‐dependent thermal behavior of SnSe nanosheets. Such nanoscale thermal behavior provides a new insight to understand the local thermal transport of 2D materials and their applications in energy consumption. [ABSTRACT FROM AUTHOR]

A novel modified adaptive neurofuzzy inference system with smoothing treatment (MANFIS) is proposed. The MANFIS model considered the smoothing treatment of initial data basing on the adaptive neurofuzzy inference system, and we used it to predict oilfield-increased production under the well stimulation. Numerical experiments show the prediction result of the novel considering smoothing treatment is better than that without smoothing treatment. This study provides a novel and feasible method for prediction of oilfield-increased production under well stimulation, and it can be helpful in the further study of oilfield development measure planning. [ABSTRACT FROM AUTHOR]

High crystalline quality and flat a‐plane aluminum gallium nitride (AlGaN) films are obtained on Si‐doped AlN templates with a moderate silane (SiH4) flow rate by metal‐organic chemical vapor deposition (MOCVD). The effects of the SiH4 flow rate on the surface morphology, crystalline quality, stress state, and optical property of a‐plane AlN templates and AlGaN films are comprehensively investigated. As the SiH4 flow rate increases from 0 to 7.0 nmol min−1, the full width at half maximum of X‐ray rocking curve values along [0001]/[1–100] directions for the AlGaN films are monotonically reduced to 1124/1143 arcsec. Meanwhile, the surface root mean square roughness value is decreased to 0.88 nm. These achievements are attributed to the suppression of the anisotropy degrees and in‐plane stress of AlN templates. In addition, an excess SiH4 flow rate leads to deteriorated surface morphologies and increased basal plane stacking fault (BPSF) densities for both AlN and AlGaN films. This work suggests that doping AlN layers with an appropriate SiH4 flow rate is a promising route to obtain high‐quality a‐plane AlGaN films for efficient nonpolar deep ultraviolet (DUV) devices. [ABSTRACT FROM AUTHOR]

• Drought resistance of vegetation productivity declined during 1982–2015. • Temperature and soil moisture largely contribute to declining drought resistance. • Drought resistance and resilience will decline in the future. Terrestrial vegetation productivity or gross primary productivity (GPP) is the main driver of the land carbon sink, and frequent and severe droughts largely affect the interannual variability of vegetation productivity and therefore land carbon sink. However, a comprehensive evaluation of spatiotemporal variation in drought response of global vegetation productivity is still lacking. Here, we used five long-term satellite-derived time series to quantify the global pattern and temporal changes of drought resistance (the ability to maintain its original levels during drought) and resilience (the ability to recover to pre-drought levels after droughts) during 1982–2015. Temporally, observed drought resistance showed a significantly declining trend across different biomes (P < 0.001), with evergreen broadleaf forests decreasing most (P < 0.001). Moreover, drought resilience showed a slight decreasing trend (P < 0.05) and has not decreased significantly among biomes. We attributed this declined resistance predominantly to temperature and soil moisture. Earth system models underestimate the drought resistance and resilience for the historical period, and project declining drought resistance and resilience to the end of 21st century. Our finding of the significant declining resistance but no increase in resilience implies the vulnerability of terrestrial carbon sinks to withstand future droughts. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of synchronisation for complex networks with hybrid coupling time delays. The control strategy consisting of adaptive control and pinning adaptive control is considered. Together with an augment Lyapunov–Krasovskii functional and using the effective mathematical techniques, several conditions are derived to guarantee a class of complex dynamical networks with hybrid coupling time-varying delays to be synchronised. Finally, some representative examples are simulated to demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper studies a simple method—Similar Constructing Method (SCM)—for constructing the exact solutions of the nonhomogeneous mixed boundary value problem for sets of n‐interval composite second‐order ordinary differential equation (ODE) with variable coefficient. Then this paper proves the correctness of the solution obtained by SCM. After that, this paper has done simulation experiment. This section uses the SCM to solve the nonhomogeneous boundary value problem of three‐interval composite Bessel equation. Solutions are presented in graphical form for various parameter values, and the influence of parameters on the solution is analyzed. The example shows that using SCM to solve the class of nonhomogeneous mixed boundary value problems of n‐interval composite second‐order linear ODE is easy, convenient, and effective. [ABSTRACT FROM AUTHOR]

Highlights • PL intensities of long-wavelength MQWs increased at the same indium content. • Photoluminescence emission became narrow. • The topography of long-wavelength MQWs was improved by this method. Abstract Wafer trays with different gaps (the distance between the top of the pocket and the bottom of the wafer) were used to grow InGaN/GaN multiple quantum wells (MQWs) in a horizontal metalorganic vapor phase epitaxy (MOVPE) reactor. The numerical reactor simulation revealed that at the similar surface temperature the gas phase temperature around the wafer increases due to an increased wafer tray temperature. This increased gas phase temperature is expected to increase the effective V/III ratio by enhanced NH 3 decomposition. Photoluminescence (PL) intensities of long-wavelength MQWs increased at the same indium content by the enhanced gas phase temperature, while the emission became narrow. This is related to a smoother topography at higher gas phase temperatures. [ABSTRACT FROM AUTHOR]

Highlights • Low growth temperature, high growth rate increased vapor supersaturation. • Large miscut angle decreased surface supersaturation. • Decreasing surface supersaturation changed morphology from 2D islands to steps. • InGaN layer with steps had the highest internal quantum efficiency. • InGaN grown on GaN substrate more easily achieved a stepped morphology. Abstract The morphology of thin InGaN layers grown on c-plane GaN substrates by metalorganic vapor phase epitaxy (MOVPE) has been studied by atomic force microscopy. Three different morphologies appeared, a stepped surface, large flat two-dimensional (2D) islands and small high three-dimensional (3D) dots. Low growth temperature and high growth rate (i.e. increased vapor supersaturation) changed the InGaN morphology from steps to 2D islands and then 3D dots (when exceeding the critical thickness for 3D dots). Larger miscut angle of GaN substrate changed the morphology from 2D islands to step by decreasing the surface supersaturation of individual terraces. InGaN layers with a stepped morphology had the highest internal quantum efficiency at similar InN mole fraction. InGaN grown on GaN substrate more easily achieved a stepped morphology compared to InGaN on GaN/sapphire templates. [ABSTRACT FROM AUTHOR]

Abstract The nonlinear grey Bernoulli model, which is often called the NGBM(1, 1), appeals considerable interest of research due to its effectiveness in time series forecasting. The success of the NGBM(1, 1) model proves that the nonlinear Bernoulli equation can be efficient to build grey prediction models. This paper is mainly aiming at building a more general nonlinear grey prediction model based on the Bernoulli equation and the modelling procedures of the GMC(1, n), which is called the nonlinear grey Bernoulli multivariate model, abbreviated as the NGBMC(1, n). The NGBMC(1, n) can be converted to the NGBM(1, 1) and the GMC(1, n) with different power parameters, thus it can be regarded as an extension of these models. Two case studies of forecasting the domestic income and foreign currency earning have been carried out to validate the effectiveness of the NGBMC(1, n) model, comparing to the novel linear multivariate grey models, including the GMC(1, n), DGM(1, n) and RDGM(1, n), and the classical ARIMA model. The advantages of the NGBMC(1, n) model in nonlinear time series forecasting over the existing linear models have been shown in the numerical results. Highlights • A novel nonlinear Bernoulli grey model NGBMC(1, n) is proposed. • The NGBMC(1, n) model is more general than the existing NGBM(1, 1) and GMC(1, n). • The NGBMC(1, n) model is quite easy-to-use and more efficient than the existing linear models. • The NGBMC(1, n) is successfully applied in tourist industry of China. • A new methodology of nonlinear grey models is provided. [ABSTRACT FROM AUTHOR]

Drying is an essential pre-treatment prior to extraction of tea polyphenols from tea leaves, which is a time and energy-intensive process. In this study, pulsed electric field (PEF) was utilized to replace the conventional thermal dehydration procedure before the phenolic extraction. The influence of different PEF conditions on total polyphenol yield from fresh tea leaves combined with a solid-liquid extraction were compared. PEF treatment at 1.00 kV/cm electric field strength, 100 pulses of 100 μs pulse duration, and 5 s pulse repetition, which delivered 22 kJ/kg and induced 1.5 °C of temperature increase, was used for further study on the extraction kinetics of green tea catechins. The results indicated that compared to oven drying, PEF pre-treatment increased the extraction rate by approximately two times, without significantly altering the phenolic profiles, as revealed by using liquid chromatography combined with mass spectrometry. Scanning electron microscopy imaging revealed that PEF pre-treatment induced the formation of inhomogeneously distributed pores and protuberances on the surface of leaf tissues, which might facilitate the penetration of extraction solvent and the migration of phenolics. This study demonstrates that PEF as a time and energy efficient processing method is a promising alternative for the conventional drying process before further tea polyphenol extraction. [ABSTRACT FROM AUTHOR]

Abstract Tremendous strides have been made in active and stable electrocatalysts of oxygen evolution reaction (OER) for water splitting to produce hydrogen. Nevertheless, the electrocatalysts with highly exposed active sites, fast electron/charge and mass transfer capabilities and long-term stability are still requisite. An efficient strategy of electrochemical activation is presented to fabricate the graphite-graphene Janus architecture and further stabilize the ultrafine Co 3 O 4 nanoparticles for OER. The wrinkled and cross-linked graphene sheets that are in-situ formed and firmly bonded on the conductive graphite foil, act as pillared spacer for fast mass transport and anchoring sites for nucleation and growth of uniform distributed Co 3 O 4 active species. The interlayer graphite contributes to the fast charge transfer as conductive substrate/framework. Benefitting from these merits, the resultant electrocatalyst achieves the outstanding OER performance with small overpotential (301 mV at 10 mA cm−2), low Tafel slope (47 mV dec−1) and long-term durability in basic medium. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

In this work, a novel time-delayed polynomial grey prediction model with the fractional order accumulation is put forward, which is abbreviated as TDPFOGM(1,1), based on the new grey system theory to predict the small sample in comparison with the existing forecasting models. The new model takes into account the nonhomogeneous term and the priority of new information can be better reflected in the in-sample model. The data in this paper all come from the existing literatures. The results demonstrate that the TDPFOGM(1,1) model outperforms the TDPGM(1,1) and FOGM(1,1) model. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA), a considerable biopolymer, suffers from the significant brittleness, which is one of its main limitations for industrial use or for biomedical applications. Introducing nanofillers represents a promising way to extend and to improve the performance of a polymer matrix. In this study, a series of octa-armed polyhedral oligomeric silsesquioxanes (POSS-(PLLA) 8 ) were developed to introduce amount of poly( l -lactide) (PLLA) arms onto the POSS particles. Then PLLA/POSS-(PLLA) 8 nanocomposites were prepared via solvent casting technique. By combining the PLLA arms onto POSS particles, the interfacial interaction between PLLA and POSS can be significantly improved and the stereocomplexed crystal are formed by heterogeneous nucleating effect of POSS-(PLLA) 8 . With the addition of 4 wt% POSS-(PLLA) 8 , an unprecedented improvement in elongation at break of the system of 600% is obtained. Simultaneously the Young's modulus is 48% improved and the tensile strength increases 56%. The PLLA/POSS-(PLLA) 8 nanocomposite possessing a high toughness and strength, improved thermal stability, as well as excellent cell attachment, spreading and proliferation is a potential biomaterial for tissue engineering applications. [ABSTRACT FROM AUTHOR]

• An innovative building material, coral sand-based PCM concrete composite is successfully prepared. • Cement encapsulation can effectively solve the problem of PCMs leakage. • The thermal property, microstructure and chemical compatibility of the coral sand-based PCM composites were studied. • The optimized replacement rate for PCM concrete composites was 50%. • The thermal regulation capacity of coral sand-based PCM concrete composites was verified through small-scale model tests. To promote the application of phase change materials (PCMs) in the field of green building, this research prepared coral sand-based PCM composites by vacuum adsorption method with coral sand as the porous carrier and polyethylene glycol 1000 as phase change material. The thermal and physical properties of the material, and its leakage characteristics after cement encapsulation were investigated through scanning electron microscope (SEM), differential scanning calorimetry (DSC), fourier transform infrared spectrometer (FT-IR), x-ray powder diffractometer (XRD), and thermal gravimetric analysis (TGA). The DSC results indicated that the coral sand-PCM composites had a melting point and latent heat capacity of 28.55℃ and 48.57 J/g, respectively. TGA and thermal cycling test demonstrated that coral sand-based PCM composites had good stability in terms of their chemical structure, thermal degradation, and cycling reliability in latent thermal energy capacity properties. The coral sand-based PCM composites were later prepared as coral sand-based PCM concrete composites by replacing coarse aggregates with different proportions. And the compressive strength of the PCM concrete composites was tested. In addition, the thermal insulation properties of coral sand-based PCM concrete composites were verified through model tests. The results of model test showed that the maximum indoor temperature differences between the Oridinary-0 and CS-50 concrete rooms were 7.45℃ during heating and 2.61℃ during cooling. The strength of coral sand-based concrete still could meet the requirements according to the structural design code at a mass substitution ratio of 50%. The CS-50 composite concrete exhibited acceptable mechanical properties and was able to regulate indoor temperatures and reduce energy consumption in buildings. Therefore, it is suitable for engineering applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sulfamethoxazole was effectively removed over a wide pH range. • CuHDC-400/GF showed excellent electrode stability in eight recycle runs. • Superoxide anions were the main ROS in the degradation of SMX. • DFT calculations were used to predict the active sites for SMX degradation. • The toxicity of the SMX degradation process was tested. In this study, a graphite felt (GF) electrode material supporting a Cu-based catalyst (CuHDC-400/GF) was prepared by a hydrothermal process and subsequent heat treatment. A heterogeneous electro-Fenton (EF) system was built to investigate the degradation of sulfamethoxazole (SMX) by the composite cathode. Scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy were used to characterize the physical and chemical properties of the composite cathode. The results show that the composite cathode CuHDC-400/GF has excellent catalytic performance, achieving 100 % removal of SMX (10 mg/L) within 45 min (aeration rate = 0.6 L min−1, current density = 5 mA cm−2, initial pH = 5.6). Furthermore, efficient removal of SMX can be achieved over a wide pH range (pH = 3–9). The electrode material can still efficiently degrade SMX after eight cycles. Compared with a heterogeneous EF system, in which the Cu catalyst was directly added to the reaction solution, using CuHDC-400/GF as the cathode realizes the in-situ catalysis of H 2 O 2 , leading to reduced catalyst consumption and enhanced electrode stability. The investigation of potential SMX degradation pathways and mechanisms revealed that the continuous production of active free radicals is facilitated by the redox cycle between CuⅠ and CuⅡ on the electrode surface, which can enable SMX degradation. Unlike the Fe-based Fenton reaction, the active superoxide radical O 2 – was identified as the major contributor to SMX degradation in this system, followed by the hydroxyl radical OH. The active sites for SMX degradation were predicted by density functional theory calculations. Combined with the measured mass/charge ratios, the possible degradation paths and intermediates of SMX were predicted. Furthermore, toxicity analysis shows that toxicity significantly declines after degradation. This work is expected to inspire subsequent research on heterogeneous EF cathode materials with high catalytic performance. [ABSTRACT FROM AUTHOR]

The challenge of routing in energy-constrained wireless sensor networks is to balance energy and extend network lifetime, and reinforcement learning is an effective method to address this problem. However, poor learning and decision-making efficiency are still the main factors affecting the network routing performance. In this research, RLR-TET is proposed as a reinforcement learning approach that evaluates the shortest routing and achieves node energy balance. First, this study employs a method in which each node broadcasts control information directly to its neighbor nodes, allowing learning to be accomplished by simple communication. Second, multiple greedy action chains form a tree structure by learning to build a greedy action chain. Third, the tree is dynamically adjusted during the learning process. Toward the root, each sensor node can obtain its optimal next hop; toward the leaf, each sensor node can achieve the update of the learning errors. Fourth, the learning errors of V-values are backpropagated along the tree to multi-layer nodes using the eligibility traces approach, achieving fast multi-step updates. In our experiments, we compared the method of this paper with five other algorithms. The number of packets delivered, the number of alive nodes, and the standard deviation of the nodes' remaining energy all improved significantly over time. Experiments have shown that our method responds quickly to network changes, improves the energy balance of network nodes, and successfully extends the lifetime of the network. [ABSTRACT FROM AUTHOR]

• The effect of SiH 4 -pretreatment on growing n-Al 0.6 Ga 0.4 N is investigated. • The 3D to 2D growth model transformation and strain relaxation during initial growth is facilitated with broken coherency and fresh-born dislocations. • The strain relaxation is almost completely contributed by dislocation inclination. • The growth of thick n-Al 0.6 Ga 0.4 N on HTA-AlN regrown layer is improved by SiH 4 -pretreatment. High-quality AlGaN-based film is the key to attain efficient deep ultraviolet emitters. In this study, we developed a silane-pretreatment method to modulate the growth mode of n-Al 0.6 Ga 0.4 N on high-temperature-annealing AlN/sapphire template (HTA-AlN) and improve the crystalline quality. It's found that pretreating the surface of HTA-AlN template by SiH 4 could disturb the pseudo-crystal epitaxy of n-Al 0.6 Ga 0.4 N and prompt the 3D growth at the AlGaN/AlN interface. The stress of n-Al 0.6 Ga 0.4 N was thus released rapidly by fresh-born dislocations. During the following growth, the growth mode of n-Al 0.6 Ga 0.4 N with SiH 4 -pretreatment transformed quickly from 3D to 2D, and the stress was released gradually because of the dislocation inclination. Besides, the threading dislocation density of 6 µm-thick n-Al 0.6 Ga 0.4 N with SiH 4 -pretreatment was reduced to 8.6 × 108 cm−2, which was one third of that without SiH 4 -pretreatments. This work paves the way for preparation and improvement of the DUV emitters. [ABSTRACT FROM AUTHOR]

Roasting is one of the most critical manufacturing steps for making Wuyi Rock tea (WRT). The role of roasting in the formation of characteristic aroma of WRT was elucidated in detail in this study. First, the volatiles formed during the roasting process of WRT were investigated by using HS-SPME-GC-MS. Next, 18 volatiles were identified as odor active compounds (flavor dilution factor ≥1) and 5 volatiles were identified as key aromatic compounds (odor activity value ≥ 1) by using HS-SPME-GC- O -MS and aroma recombination tests. Furthermore, model reactions of fructose, amino acids, and epicatechin, mimicking the Maillard reaction occurred during roasting, indicated that roasting temperature, amino acid type, and catechins were critical factors for the formation of the characteristic aroma of WRT. In specific, the temperature above 120 °C facilitated the formation of 2,3-diethyl-5-methylpyrazine, 5-methyl-2-furancarboxaldehyde and 2,6-diethyl pyrazine. And high temperature roasting also facilitated the elimination of off-flavors with grassy odor formed during tea storage. The model reactions of fructose with alanine and lysine at 130 °C formed the highest abundance of characteristic aroma of WRT. Additionally, it was also found that epicatechin inhibited the formation of the characteristic aromatic compounds of WRT. Taken together, this study provides details regarding the dynamics of volatiles during roasting, and elucidates the roles of roasting on the formation of the characteristic aroma of WRT. • Pyrazines, pyrroles and furans were formed after high temperature roasting. • High temperature roasting facilitated the elimination of grassy flavor in tea. • High temperature roasting was critical for WRT characteristic aroma formation. • Catechins inhibited the formation of the roasted aroma compounds. [ABSTRACT FROM AUTHOR]

Hong Qu, which mainly contains Monascus sp. and other microorganisms, as well as numerous microbial metabolites, is used as the fermentation starter of Hong Qu glutinous rice wine, a traditional alcoholic beverage. Two widely-used types of Hong Qu, namely Wuyi Qu (WYQ) and Gutian Qu (GTQ), were thoroughly compared for their fermentation properties, volatile profiles, and microbiota structures in this study. Significantly higher color value, glucoamylase and α-amylase activities were discovered in WYQ. And substantial variation in volatile components and microbial communities were also observed between them. It was identified that bacterial genus Burkholderia dominated GTQ (71.62%) and Bacillus dominated WYQ (44.73%), while Monascus purpureus was the most abundant fungal species in both types of starters (76.99%). In addition, 213 bacterial genera and 150 fungal species with low-abundance were also detected. Since the Linear Discriminant Analysis Effect Size algorithm, 14 genus-level bacterial taxa and 10 species-level fungal taxa could be utilized to distinguish these two types of starters. Moreover, the potential correlation of the volatile components and microbiota within WYQ and GTQ were further analyzed, by utilizing Partial Least Squares Discriminant Analysis. Ultimately, this study provides detailed insight into the volatile profiles and microbial communities presented in Hong Qu. [ABSTRACT FROM AUTHOR]

Prediction of petroleum production plays a key role in the petroleum engineering, but an accurate prediction is difficult to achieve due to the complex underground conditions. In this paper, we employ the kernel method to extend the Arps decline model into a nonlinear multivariate prediction model, which is called the nonlinear extension of Arps decline model (NEA). The basic structure of the NEA is developed from the Arps exponential decline equation, and the kernel method is employed to build a nonlinear combination of the input series. Thus, the NEA is efficient to deal with the nonlinear relationship between the input series and the petroleum production with a one-step linear recursion, which combines the merits of commonly used decline curve methods and intelligent methods. The case studies are carried out with the production data from two real-world oil field in China and India to assess the efficiency of the NEA model, and the results show that the NEA is eligible to describe the nonlinear relationship between the influence factors and the oil production, and it is applicable to make accurate forecasts for the oil production in the real applications. [ABSTRACT FROM AUTHOR]

The government of China is now trying to use natural gas as partial substitute of other fuels, such as coal and gasoline. Developing the natural gas industry has been written in the 13th Five Year Plan of China, which is the most important official policy of China. Predicting the natural gas consumption comes to be very important for the government and energy companies to make decisions. In this paper, we propose a novel time-delayed polynomial grey prediction model, which is abbreviated as TDPGM(1, 1), based on the grey system theory to forecast the natural gas consumption of China in comparison with the commonly used prediction models. The data from 1995 to 2004 are used to build the prediction models, and the data from 2005 to 2013 are used to assess the modelling accuracy. The results show that the TDPGM(1, 1) model outperforms the other models. Finally the TDPGM(1, 1) model is used to forecast the natural gas consumption of China from 2014 to 2020 and different results from the previous research results have been obtained. [ABSTRACT FROM AUTHOR]