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IntroductionAccurate and rapid identification of cabbage posture is crucial for minimizing damage to cabbage heads during mechanical harvesting. However, due to the structural complexity of cabbages, current methods encounter challenges in detecting and segmenting the heads and roots. Therefore, exploring efficient cabbage posture prediction methods is of great significance.MethodsThis study introduces YOLOv5-POS, an innovative cabbage posture prediction approach. Building on the YOLOv5s backbone, this method enhances detection and segmentation capabilities for cabbage heads and roots by incorporating C-RepGFPN to replace the traditional Neck layer, optimizing feature extraction and upsampling strategies, and refining the C-Seg segmentation head. Additionally, a cabbage root growth prediction model based on Bézier curves is proposed, using the geometric moment method for key point identification and the anti-gravity stem-seeking principle to determine root-head junctions. It performs precision root growth curve fitting and prediction, effectively overcoming the challenge posed by the outer leaves completely enclosing the cabbage root stem.Results and discussionYOLOv5-POS was tested on a multi-variety cabbage dataset, achieving an F1 score of 98.8% for head and root detection, with an instance segmentation accuracy of 93.5%. The posture recognition model demonstrated an average absolute error of 1.38° and an average relative error of 2.32%, while the root growth prediction model reached an accuracy of 98%. Cabbage posture recognition was completed within 28 milliseconds, enabling real-time harvesting. The enhanced model effectively addresses the challenges of cabbage segmentation and posture prediction, providing a highly accurate and efficient solution for automated harvesting, minimizing crop damage, and improving operational efficiency.

In order to explore the efficient use of water and nitrogen for winter wheat under irrigation with micro-sprinkling hose, two-season field experiments were conducted to evaluate the effects of irrigation levels and nitrogen application rate on yield, water productivity (WP) and nitrogen partial factor productivity (NPFP). Three irrigation levels were 60 %, 65 %, and 70 % field capacity (FC) during the reviving to jointing stage, 65 %, 70 %, and 75 % FC after the jointing stage, referred to as W1, W2 and W3, respectively. The irrigating water quota is 30 mm. The five N topdressing period treatments were reviving period + booting stage (N1), jointing + booting stage (N2), reviving period (N3), jointing stage (N4), and booting stage (N5). The results showed that the water consumption, leaf area index, plant height, biomass, grain yield, and NPFP increased with an increase in irrigation amount, and the WP decreased with an increase in irrigation amount. Nitrogen applied during the reviving period was beneficial for increasing grain yield, WP, and NPFP under the irrigation level W1; nitrogen applied during the jointing period was beneficial for increasing grain yield, WP, and NPFP for winter wheat under the W2 and W3 irrigation levels. The W3N2 treatment resulted in the highest grain yield (8.98 t·ha−1), but it was not significant difference from W2N2 (average of 8.92 t·ha−1). After a comprehensive evaluation based on grain yield, WP and NPFP, the appropriate modes of irrigation and nitrogen is the treatment of W2N2 (65 % and 70 % FC irrigation treatments during the reviving to jointing stage and the stages after jointing stage, respectively; the nitrogen topdressing during jointing + booting stage) for winter wheat using micro-sprinkling hose irrigation in North China.

Vibration measurements can be used to evaluate the operation status of power equipment and are widely applied in equipment quality inspection and fault identification. Event-sensing technology can sense the change in surface light intensity caused by object vibration and provide a visual description of vibration behavior. Based on the analysis of the principle underlying the transformation of vibration behavior into event flow data by an event sensor, this paper proposes an algorithm to reconstruct event flow data into a relationship correlating vibration displacement and time to extract the amplitude-frequency characteristics of the vibration signal. A vibration measurement test platform is constructed, and feasibility and effectiveness tests are performed for the vibration motor and other power equipment. The results show that event-sensing technology can effectively perceive the surface vibration behavior of power and provide a wide dynamic range. Furthermore, the vibration measurement and visualization algorithm for power equipment constructed using this technology offers high measurement accuracy and efficiency. The results of this study provide a new noncontact and visual method for locating vibrations and performing amplitude-frequency analysis on power equipment.

Accurate identification of rice ears is crucial for assessing rice yield. Present research mainly relies on single-scale image data for rice ears detection and counting. However, these approaches are susceptible to misdetection and omission due to the intricate environmental conditions in fields. The combination of multi-source images can better overcome the limitations of single-scale images. In this study, based on the YOLOv5s target detection algorithm, a method for rice ears detection and counting applicable to multi-source images is proposed by integrating image data collected by cell phones and UAVs during the rice heading and maturity periods. The proposed method introduces Attention-based Intrascale Feature Interaction (AIFI) to reconstruct the backbone feature extraction network, optimizing feature expression interaction and enhancing handling of the model of advanced semantic information. Additionally, Simplify Optimal Transport Assignment (SimOTA) is employed to achieve a more refined label assignment strategy, thereby optimizing detection performance of the model and addressing difficulties in detecting multiple targets in high-density rice ears environments. Finally, Channel-wise Knowledge Distillation for Dense Prediction (CWD) is utilized to enhance the performance of the model in dense prediction tasks by transferring knowledge between different channels. The experimental results demonstrated good performance of the model on datasets comprising rice at the heading and maturity stages, achieving Precision, Recall, and mAP values of 93%, 85.3%, and 90.3%, respectively. The coefficients of determination (R $^{2}$ ) for the linear fit between test results and the actual statistical results of the model were 0.91, 0.91, 0.90, and 0.88, respectively. The proposed model performs well in the mixed dataset and can be utilized more effectively for accurate identification and counting of rice ears.

Among tropical fruit trees, coconut holds significant edible and economic importance. The natural growth of coconuts faces a challenge in the form of low temperatures, which is a crucial factor among adverse environmental stresses impacting their geographical distribution. Hence, it is essential to enhance our comprehension of the molecular mechanisms through which cold stress influences various coconut varieties. We employed analyses of leaf growth morphology and physiological traits to examine how coconuts respond to low temperatures over 2-hour, 8-hour, 2-day, and 7-day intervals. Additionally, we performed transcriptome and metabolome analyses to identify the molecular and physiological shifts in two coconut varieties displaying distinct sensitivities to the cold stress. As the length of cold stress extended, there was a prominent escalation within the soluble protein (SP), proline (Pro) concentrations, the activity of peroxidase (POD) and superoxide dismutase (SOD) in the leaves. Contrariwise, the activity of glutathione peroxidase (GSH) underwent a substantial reduction during this period. The widespread analysis of metabolome and transcriptome disclosed a nexus of genes and metabolites intricately cold stress were chiefly involved in pathways centered around amino acid, flavonoid, carbohydrate and lipid metabolism. We perceived several stress-responsive metabolites, such as flavonoids, carbohydrates, lipids, and amino acids, which unveiled considerably, lower in the genotype subtle to cold stress. Furthermore, we uncovered pivotal genes in the amino acid biosynthesis, antioxidant system and flavonoid biosynthesis pathway that presented down-regulation in coconut varieties sensitive to cold stress. This study broadly enriches our contemporary perception of the molecular machinery that contributes to altering levels of cold stress tolerance amid coconut genotypes. It also unlocks several unique prospects for exploration in the areas of breeding or engineering, aiming to identifying tolerant and/or sensitive coconut varieties encompassing multi-omics layers in response to cold stress conditions.

Summary: Phenolic chemicals are important building blocks in chemical and material industries. In this protocol, we describe the preparation of CeO2-CuO catalysts and the application in the decarboxylative oxidation reaction of benzoic acids to phenols. Furthermore, we describe how to modify the basic sites of CeO2-CuO catalysts by CO2 treatment to increase the selectivity of phenol and the regeneration process of used catalyst.For complete details on the use and execution of this protocol, please refer to Du et al. (2023).1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Utilizing renewable lignocellulosic resources for wastewater remediation is crucial to achieving sustainable social development. However, the resulting by-products and the synthetic process characterized by complexity, high cost, and environmental pollution limit the further development of lignocellulose-based materials. Here, we developed a sustainable strategy that involved a new functional deep eutectic solvent (DES) to deconstruct industrial xylose residue into cellulose-rich residue with carboxyl groups, lignin with carboxyl and quaternary ammonium salt groups, and DES effluent rich in lignin fragments. Subsequently, these fractions equipped with customized functionality were used to produce efficient wastewater remediation materials in cost-effective and environmentally sound manners, namely, photocatalyst prepared by carboxyl-modified cellulose residue, biochar-based adsorbent originated from modified lignin, and flocculant synthesized by self-catalytic in situ copolymerization of residual DES effluent at room temperature. Under the no-waste principle, this strategy upgraded the whole components of waste lignocellulose into high-value-added wastewater remediation materials with excellent universality. These materials in coordination with each other can stepwise purify high-hazardous mineral processing wastewater into drinkable water, including the removal of 99.81% of suspended solids, almost all various heavy metal ions, and 97.09% chemical oxygen demand, respectively. This work provided promising solutions and blueprints for lignocellulosic resources to alleviate water shortages while also advancing the global goal of carbon neutrality.

IntroductionRecognizing wheat ears plays a crucial role in predicting wheat yield. Employing deep learning methods for wheat ears identification is the mainstream method in current research and applications. However, such methods still face challenges, such as high computational parameter volume, large model weights, and slow processing speeds, making it difficult to apply them for real-time identification tasks on limited hardware resources in the wheat field. Therefore, exploring lightweight wheat ears detection methods for real-time recognition holds significant importance.MethodsThis study proposes a lightweight method for detecting and counting wheat ears based on YOLOv5s. It utilizes the ShuffleNetV2 lightweight convolutional neural network to optimize the YOLOv5s model by reducing the number of parameters and simplifying the complexity of the calculation processes. In addition, a lightweight upsampling operator content-aware reassembly of features is introduced in the feature pyramid structure to eliminate the impact of the lightweight process on the model detection performance. This approach aims to improve the spatial resolution of the feature images, enhance the effectiveness of the perceptual field, and reduce information loss. Finally, by introducing the dynamic target detection head, the shape of the detection head and the feature extraction strategy can be dynamically adjusted, and the detection accuracy can be improved when encountering wheat ears with large-scale changes, diverse shapes, or significant orientation variations.Results and discussionThis study uses the global wheat head detection dataset and incorporates the local experimental dataset to improve the robustness and generalization of the proposed model. The weight, FLOPs and mAP of this model are 2.9 MB, 2.5 * 109 and 94.8%, respectively. The linear fitting determination coefficients R2 for the model test result and actual value of global wheat head detection dataset and local experimental Site are 0.94 and 0.97, respectively. The improved lightweight model can better meet the requirements of precision wheat ears counting and play an important role in embedded systems, mobile devices, or other hardware systems with limited computing resources.

Heat stress (HS) negatively affects the growth, metabolism, reproduction, and productivity of plants and its adversary can be lessened through using exogenous substance (ES). With an extensive and comprehensive review of 136 collective literatures published for last two decades on alleviation of HS in plants through applying 65 ESs, we have proposed and discussed in details six mechanisms that underline their different effects on plant responses and regulations against HS at the structural, biochemical, molecular level through: 1) improving antioxidant pathways in plants; 2) promoting the synthesis of osmotic regulatory substances in cells; 3) enhancing photosynthetic functions in leaves; 4) adjusting the hormone balance, 5) regulating the expression of HS defensive genes and signal transduction; and 6) microbe-involved regulatory processes. More detailed information, research progress, perspectives and potential breakthroughs on using various ESs in alleviating plant HS are outlined to benefit researchers working on the subject to have a more comprehensive understanding of ESs effects and their underlying tolerance against plant HS.

Since their high power-to-volume property, electric machines with 3D magnetic flux (3D-flux) structure are of great current interest. In them, the flux path is typically achieved by utilizing a soft magnetic composite (SMC) material to minimize the eddy current losses. Here, laser powder bed fusion (LPBF) technique is employed to manufacture a soft magnetic core (Fe-3.5 wt%Si alloy) with the following advantages: i) the (001) texture of Fe-Si alloy is well aligned with the Z direction of the 3D-flux path, which is the easiest magnetization direction in the cubic system; ii) the strength and ductility of the annealed alloy are far superior to those of SMCs. The alternating-current ring method was employed to measure the magnetic properties and a simulation of the 3D-flux electric machine was conducted. The results illustrated that the rotary torque generated with the additively manufactured alloy is 19.1% higher than that of SMCs in the weak magnetic field excited by ferrite at the 50 Hz frequency. However, it is important to note that the additively manufactured alloy also exhibited higher total iron loss in strong magnetic field and high electric frequency, indicating a need for further research to optimize the microstructure and reduce losses for medium/high frequency applications.

Summary: Phenols are important building blocks widely applied in many fields. The pronounced orientational effect of the phenolic hydroxyl group makes achieving selective synthesis of meta-phenols challenging. Accessing meta-phenols needs lengthy synthetic sequences. Herein, we first developed a heterogeneous CO2-mediated CeO2-5CuO catalyst for decarboxylative oxidation of benzoic acids with a more than 80% selectivity to meta-phenols. This technology is based on a traceless directing group relay method. The CeO2-CuO catalysts with different Ce/Cu ratios exhibited controllable reaction selectivity between decarboxylation and decarboxylative oxidation. Spectroscopy experiments and computational studies showed the adsorption state of benzoic acid was found to be crucial for subsequent reaction pathways. The moderate adsorption on CO2-mediated CeO2-5CuO catalyst contributes to the distinct selectivity of phenol. Furthermore, the paddlewheel intermediate facilitates the synthesis of meta-phenols from benzoic acids. This traceless directing group method would promote the development of useful one-pot meta-substituted phenols from bio-based benzoic acids.

Silicon steel is a widely used soft magnetic material that requires different texture components for different applications, typically classified as grain-oriented or non-oriented. However, the methods of fabricating such types of silicon steel via laser-powder bed fusion (LPBF) have not been fully investigated. In this study, near grain-oriented and near non-oriented Fe-3.5 wt.%Si silicon steel is fabricated using LPBF by controlling processing parameters. Different textures are investigated using electron backscatter diffraction (EBSD), and the morphology of the molten pool is characterized by optical microscopy (OM) and scanning electron microscopy (SEM). Magnetic properties are measured with alternating current (AC) method. The results show that reducing both the linear energy density (LED) and laser power leads to a change in the side morphology of the molten pool from large, flat, and well-overlapped to small, protuberant, and less-overlapped, resulting in an extremely strong θ-fiber texture or a random distribution of grain orientations, respectively. Additionally, reducing both the laser power and scanning speed causes the top morphology of the molten pool to change from teardrop to elliptical shape at the trailing edge, resulting in a shift in the angle between the 〈001〉 of grains in the θ-fiber texture and the scanning direction from 45° to 30°. Samples with fewer defects (i.e., larger grain size and fewer pores) and a larger area fraction of 〈001〉//H exhibit higher permeability, although this superiority is not so significant due to residual stress and high dislocation in the as-built samples. This study provides insight into the relationship between processing parameters, texture evolution, and magnetic properties in LPBFed silicon steel.

The aim of this study was to investigate the impact of water and nitrogen regulation on the characteristics of water and fertilizer demands and the yield, quality, and efficiencies of the water and nitrogen utilization of peanuts cultivated under mulched drip irrigation in a desert–oasis region. The experiment, conducted in Urumqi, Xinjiang, centered on elucidating the response mechanisms governing peanut growth, yield, quality, water consumption patterns, and fertilizer characteristics during the reproductive period under the influence of water and nitrogen regulation. In the field experiments, three irrigation levels were implemented, denoted as W1 (irrigation water quota of 22.5 mm), W2 (irrigation water quota of 30 mm), and W3 (irrigation water quota of 37.5 mm). Additionally, two nitrogen application levels, labeled N1 (nitrogen application rate of 77.5 kg·ha−1) and N2 (a nitrogen application rate of 110 kg·ha−1), were applied, resulting in seven treatments. A control treatment (CK), which involved no nitrogen application, was also included in the experimental design. The results indicate a direct correlation between the increment in the irrigation quota and increases in farmland water-related parameters, including water consumption, daily water consumption intensity, and water consumption percentage. The nitrogen harvest index (NHI) demonstrated a higher value in the absence of nitrogen application compared to the treatment with elevated nitrogen levels. The application of nitrogen resulted in an elevation in both nitrogen accumulation and nitrogen absorption efficiency within pods and plants. When subjected to identical nitrogen application conditions, irrigation proved to be advantageous in enhancing water-use efficiency (WUE), nitrogen partial factor productivity (NPFP), and the yield of peanut pods. The contribution rate of water to pod yield and WUE exceeded that of nitrogen, while the contribution rate of nitrogen to nitrogen-use efficiency (NUE) was higher. The total water consumption for achieving a high yield and enhanced water- and nitrogen-use efficiencies in peanuts cultivated under drip irrigation with film mulching was approximately 402.57 mm. Taking into account yield, quality, and water- and nitrogen-used efficiencies, the use of an irrigation quota of 37.5 mm, an irrigation cycle of 10–15 days, and a nitrogen application rate of 110 kg·ha−1 can be regarded as an appropriate water and nitrogen management approach for peanut cultivation under mulched drip irrigation in Xinjiang.

The optimization of irrigation and fertilization indexes for peanuts with drip irrigation is urgently needed in Xinjiang. A field experiment was conducted during the 2021 peanut growing season at Urumqi, Xinjiang, in Northwestern China, to evaluate the effects of different water and nitrogen treatments on the growth, yield, and water and nitrogen utilization of peanuts. In field experiments, we set up three irrigation levels (irrigation water quotas of 22.5, 30, and 37.5 mm, respectively, for W1, W2, and W3), two nitrogen application levels (77.5 and 110 kg·ha−1, recorded as N1 and N2), and a control treatment (W2N0) that did not include the application of nitrogen. The results showed that nitrogen application enhanced the growth, physiological indexes, yield, and water use efficiency of the W1, W2, and W3 treatments when the irrigation volume remained the same. In comparison with no nitrogen application (W2N0), the peanut growth, physiological indexes, yield, and water use efficiency improved with increasing irrigation amounts in the N1 and N2 treatments. With an increase in the irrigation volume, the water use efficiency grew; the W3N2 treatment had the highest water use efficiency, which was 1.32 kg·m−3. The total water consumption and reproductive-stage water consumption of the peanuts in all treatments increased with the irrigation volume, and a high yield was achieved at 402.57 mm, which was 5.2974 Mg·ha−1. In the W1, W2, and W3 treatments, the nitrogen partial factor productivity significantly decreased as the nitrogen application increased, with the nitrogen partial factor productivity in the W3N1 treatment being the highest, at 60.61 kg·kg−1. A comprehensive evaluation based on principal component analysis assigned W3N2 the higher score. These findings suggest that irrigation water quotas of 37.5 mm should be coupled with 110 kg·ha−1 nitrogen applications for peanuts using drip irrigation in mulch film in Xinjiang.

Abstract Chinese hickory shell, a by-product of the food industry, is still not utilized and urgent to develop sustainable technologies for its valorization. This research focuses on the systematical evaluation of degraded products and xylooligosaccharide production with high yield from the shell via hydrothermal process. The pretreatment was carried out in a bath pressurized reactor at 140–220 °C for 0.5–2 h. The results indicated that the pretreatment condition strongly affected the chemical structures and compositions of the liquid fraction. The maximum yield of XOS (55.3 wt%) with limitation of by-products formation was achieved at 160 °C for 2 h. High temperature (220 °C) and short time (0.5 h) contributed to hydrolysis of xylooligosaccharide with high DP to yield 37.5 wt% xylooligosaccharide with DP from 2 to 6. Xylooligosaccharide obtained mainly consisted of xylan with branches according to the HSQC NMR analysis. Overall, the production of XOS with a high yield from food waste will facilitate the valorization of food waste in the biorefinery industry. Graphical Abstract

The objective of this research was to improve the accuracy and representativeness of experimental plot studies by determining the optimum plot area and replication number for winter wheat with border irrigation. Considering the spatial distribution of soil water content, the border effect in relation to crop growth, and the lateral seepage of soil water, we sought to study and optimize the area and specifications of irrigation experiment plots with different levels and replicates. The results show that the experimental irrigation plot consisted of two parts—the core area and the guard area. The most suitable area for the experiment plot core area, with a single level and without replicates, was 60–80 m2. The core experimental area can be arranged with two replicates per 40 m2, with differences in soil moisture content between the treatments reaching more than 15% at the two experiment levels. Each plot comprised two replicates, or if they were 20 m2, then they contained three replicates; when the soil moisture contents differed between 10% and 15%, the area of each replicate plot was 80 m2, comprising two replicates, or 30 m2 with three replicates. When the difference in soil moisture content between the treatments exceeded 15% with the three experimental levels, the area of each plot was 30 m2 and they contained two replicates, or 20 m2 containing three replicates; at differences of 10% to 15%, each replicate plot was 50 m2 containing two replicates, or 30 m2 with three replicates. The experimental plots were rectangular, with irrigation furrows dug lengthwise; therefore, the plots had aspect ratios between 7:1 and 5:1. The width of the buffer area was over 60 cm. The effect of the border on plant height and LAI for winter wheat primarily emerged with one to three rows (20–60 cm) at the jointing stage, while the effect on grain yield and biomass in winter wheat mainly emerged with one to two rows (20–40 cm). The conclusions of this research will inform the development of surface irrigation methods for silt loam in northern Henan, as a reference for optimizing experiment plots employing border irrigation with different soil textures.

Coconut water (CW) is a popular and healthful beverage, and ensuring its quality is crucial for consumer satisfaction. This study aimed to explore the potential of near-infrared spectroscopy (NIRS) and chemometric methods for analyzing CW quality and distinguishing samples based on postharvest storage time, cultivar, and maturity. CW from nuts of Wenye No. 2 and Wenye No. 4 cultivars in China, with varying postharvest storage time and maturities, were subjected to NIRS analysis. Partial least squares regression (PLSR) models were developed to predict reducing sugar and soluble sugar contents, revealing moderate applicability but lacking accuracy, with the residual prediction deviation (RPD) values ranging from 1.54 to 1.83. Models for TSS, pH, and TSS/pH exhibited poor performance with RPD values below 1.4, indicating limited predictability. However, the study achieved a total correct classification rate exceeding 95% through orthogonal partial least squares discriminant analysis (OPLS-DA) models, effectively discriminating CW samples based on postharvest storage time, cultivar, and maturity. These findings highlight the potential of NIRS combined with appropriate chemometric methods as a valuable tool for analyzing CW quality and efficiently distinguishing samples. NIRS and chemometric techniques enhance quality control in coconut water, ensuring consumer satisfaction and product integrity.

Abstract Background Recent researches have suggested that long noncoding RNA (lncRNA) is involved in the tumorigenesis and development of stomach cancer (SC). This meta-analysis aimed to identify the diagnostic performance of circulating lncRNAs in SC. Methods All relevant studies were systematically searched through PubMed, Web of Science, Cochrane Library, and EMBASE databases. The diagnostic values of lncRNAs were mainly assessed by pooled sensitivity, specificity, and summary receiver operating characteristic area under the curve (SROC AUC). Meta-DiSc 1.4, Review Manager 5.3, and STATA 12.0 were used for statistical analysis. The protocol for this systematic review was registered on INPLASY (INPLASY202120079) and is available in full on the inplasy.com ( https://doi.org/10.37766/inplasy2021.2.0079 ). Results A total of 42 eligible studies were included in this meta-analysis. The pooled sensitivity, specificity, and SROC AUC were 0.78 (95%CI 0.75–0.81), 0.75 (95%CI 0.71–0.78), and 0.83 (95%CI 0.80–0.86), respectively, suggesting that the lncRNAs test had a high accuracy for the diagnosis of SC. Obvious heterogeneity might come from the type of lncRNA through subgroup and meta-regression analysis. Fagan diagram shows the clinical value of lncRNAs test in SC. Conclusions Abnormal expression of circulating lncRNAs exhibits a high efficacy for diagnosing SC, which is promising in clinical application.

Selective hydrogenation of 5-(hydroxymethyl)furfural (HMF) to 5-Methylfurfural using H2 as reductant is very attractive, but remains challenging. Here, the authors report that isolated single atomic catalysts can catalyze the reaction efficiently with selectivity >99% at complete conversion of HMF.

Abstract Background Application of exogenous glycine betaine (GB) and exogenous salicylic acid (SA) mitigates the adverse effects of salinity. Foliar spraying with exogenous GB or SA alleviates salt stress in plants by increasing leaf gas exchange and stimulating antioxidant enzyme activity. The effects of foliar application of exogenous GB and SA on the physiology and biochemistry of cotton seedlings subjected to salt stress remain unclear. Results Results showed that salt stress of 150 mM NaCl significantly reduced leaf gas exchange and chlorophyll fluorescence and decreased photosynthetic pigment quantities and leaf relative water content. Foliar spray concentrations of 5.0 mM exogenous GB and 1.0 mM exogenous SA promoted gas exchange and fluorescence in cotton seedlings, increased quantities of chlorophyll pigments, and stimulated the antioxidant enzyme activity. The foliar spray also increased leaf relative water content and endogenous GB and SA content in comparison with the salt-stressed only control. Despite the salt-induced increase in antioxidant enzyme content, exogenous GB and SA in experimental concentrations significantly increased the activity of glutathione reductase, ascorbate peroxidase, superoxide dismutase, catalase and peroxidase, and decreased malondialdehyde content under salt stress. Across all experimental foliar spray GB and SA concentrations, the photochemical efficiency of photosystem II (F V /F M ) reached a peak at a concentration of 5.0 mM GB. The net photosynthetic rate (P n ) and F V /F M were positively correlated with chlorophyll a and chlorophyll b content in response to foliar spraying of exogenous GB and SA under salt stress. Conclusions We concluded, from our results, that concentrations of 5.0 mM GB or 1.0 mM SA are optimal choices for mitigating NaCl-induced damage in cotton seedlings because they promote leaf photosynthesis, increase quantities of photosynthetic pigments, and stimulate antioxidant enzyme activity. Among, 5.0 mM GB and 1.0 mM SA, the best performance in enhancing endogenous GB and SA concentrations was obtained with the foliar application of 1.0 mM SA under salt stress.

In the context of the industrial internet,automatic and effective anomaly detection methods are of great significance to the safe and stable production of industrial systems.Traditional anomaly detection methods have the disadvantages of requiring a large number of labeled samples,and not adapting to high-dimensional time series data.Aiming at these limitations,an industrial system anomaly detection method based on LSTM (long short-term memory)auto-encoder was proposed.Firstly,to address the limitation of relying on labeled samples,an encoder used to learn the features and patterns of a large number of normal samples in an unsupervised manner.Then,anomaly detection was performed via reconstructing samples and calculating the reconstruction error.Secondly,to adapt to high-dimensional time series data,a BiLSTM (bidirectional LSTM) was used as an encoder,and then the potential characteristics of multi-dimensional time series data were mined.Experiments based on a real paper industry data set which demonstrate this method has improved the existing unsupervised anomaly detection methods in various indicators,and the overall accuracy of the detection has reached 93.4%.

The influence of concrete components on projectile penetration is significant. To study the relationship between the equivalent mechanical properties and components of concrete under a penetration load, concrete is simplified as a two-phase composite of coarse aggregate and mortar, and a meso-mechanical model is established, including the equivalent equation of state model, the equivalent confining pressure strength model and the equivalent dynamic tensile strength model, considering shear stress, large deformation and pore compression. Tests of the mechanical properties of mortar, concrete and limestone were conducted; the results show that the equivalent mechanical properties of concrete calculated by the meso-mechanical model are consistent with the test results, and the equivalent mechanical properties of concrete with different volume fractions of coarse aggregate are obtained. Meso-scale and macro-scale numerical simulations of a projectile penetrating into concrete are carried out, the penetration depths obtained by meso-scale and macro-scale numerical simulations are consistent for different volume fractions of coarse aggregate and different velocities of the projectile, which verifies the rationality of the meso-mechanical model. Keywords: Meso-mechanical, Inclusion model, Concrete, Penetration, Projectile

This article scientifically studies the direct impact of climate problems on the time transition of reference crop evapotranspiration in the Xinjiang Autonomous Region of China from 1957 to 2017, which is conducive to formulating irrigation scheduling and adaptive capacity countermeasures. The objective of this study is to investigate the impacts of climate change on ETo for the cotton growing seasons. The meteorological data were collected from 48 meteorological stations in the region and analyzed using the Mann–Kendall test and linear trend. The results show the following points: (1) the ETo decreases from low to high elevations, and with the increase in northern latitude. (2) The annual mean ETo and average values of ETo during the growing seasons for cotton exhibited two abrupt changes in the period 1957–2017, with the first abrupt change in 1995 to 1999 and the second abrupt change in 2006 to 2011. (3) The ETo in Xinjiang of China demonstrates a decreasing trend during 1957–1996; a significant decreasing trend during 1997–2008; and a significant increasing trend during 2009–2017.

Brackish water has to be used to irrigate crops for harvest due to the scarcity of freshwater resources. However, brackish water irrigation may cause secondary soil salinization. Whether the combined utilization of different non-conventional water resources could relieve the risk of secondary soil salinization has not been reported. In order to explore the safe and rational utilization of brackish water in areas where freshwater resources are scarce, a pot experiment was conducted to study the risk of secondary soil mixed irrigation and rotational irrigation using brackish water and reclaimed water or freshwater. The results indicated that: (1) Short-term irrigation using reclaimed water did not cause secondary soil salinization, although increasing soil pH value, ESP, and SAR. The indices did not exceed the threshold of soil salinization. (2) Compared with mixed irrigation using brackish–freshwater, the contents of soil exchangeable Ca2+, K+, and Mg2+ increased, and the content of soil exchangeable Na+ decreased under rotational irrigation using brackish-reclaimed water. In addition, the contents of soil exchangeable Na+ and Mg2+ under mixed irrigation or rotational irrigation were significantly lower, and the exchangeable K+ content of the soil was higher compared with brackish water irrigation. The exchangeable Ca2+ content under rotational irrigation was higher than that of brackish water irrigation, while the reverse was seen under mixed irrigation. (3) For different combined utilization modes of brackish water and reclaimed water, the ESP and SAR were the lowest under rotational irrigation, followed by mixed irrigation and brackish water irrigation. The ESP under brackish water treatment exceeded 15%, indicating a certain risk of salinization, while ESPs under other treatments were below 15%. Under mixed irrigation or rational irrigation using reclaimed-brackish water, the higher the proportion or rotational times of reclaimed water, the lower the risk of secondary soil salinization. Therefore, short-term combined irrigation using brackish water and reclaimed water will not cause the risk of secondary soil salinization, but further experiments need to verify or cooperate with other agronomic measures in long-term utilization.

In this paper, Ta50-Zr50 and Ta45-Zr45-Nb10 alloys were compounded by casting. Quasi-static and dynamic compression tests were applied for both alloys, and also the role of Nb additive on the mechanical property of Zr-Ta alloy, was studied. The microstructure characterization demonstrated that both alloys had relative homogeneous structure with micro-laminate structure inside grains. The Nb additives increased the strength of the alloy by various strain rates, while the ductility of the alloys was decreased. The various parameters of constitutive equations for both alloys were obtained by fitting data. The constitutive equations are applied in theoretical models, the simulation software helps to predict the strength of alloy through various strain rates.

In this paper, to enhance the toughness and heat resistance properties of polylactic acid (PLA)/polybutylene succinate (PBS) composites, the PLA/PBS matrix was modified by different glass fiber (GF), GF/SiO2, and GF/(Polyaluminium chloride) PAC fillers. Additionally, the effect of filler type, filler content, components interaction and composite structure on the mechanical and thermal properties of the PLA/PBS composites was researched. The results showed that the addition of GF, GF/SiO2 and GF/PAC make the PLA/PBS composites appear significantly higher mechanical properties compared with the pristine PLA/PBS composite. Among the different inorganic fillers, the 10%GF/1%SiO2 fillers showed excellent strengthening, toughening and heat resistant effects. Compared with the pristine PLA/PBS matrix, the tensile strength, elastic modulus, flexural strength, flexural modulus and Izod impact strength improved by 36.28%, 70.74%, 67.95%, 66.61% and 135.68%, respectively. Considering the above, when the weight loss rate was 50%, the thermal decomposition temperature of the 10%GF/1%SiO2 modified PLA/PBS composites was the highest 412.83 °C and its Vicat softening point was up to 116.8 °C. In a word, the 10%GF/1%SiO2 reinforced PLA/PBS composites exhibit excellent mechanical and thermal properties, which broadens the application of biodegradable materials in specific scenarios.

The selective transformation of chitin into various renewable N-containing chemicals and medicines has attracted increasing attention. However, the N-acetyl groups in chitin construct strong hydrogen bond networks, which restricts its depolymerization and transformation. The selective conversion of robust chitin commonly requires considerable base catalysts to remove the N-acetyl group as a byproduct in advance, which is non-compliance with the principle of atomic economy. Herein, for the first time we demonstrate a novel approach to achieve the selective utilization of the N-acetyl group in chitin for transamidation of chitin with amines. A series of amine derivatives, mainly including aliphatic amine, cyclic amine and functionalized aromatic amine, could be selectively converted into the corresponding amide products frequently found in pharmaceuticals. Furthermore, the solid residue after removing the acetyl group (denoted as De-chitin) with the sufficient exposure of -NH2 groups as a solid base catalyst shows excellent performance in the aldol condensation reaction of furfural and acetone to produce fuel precursors. Our process provides a strategy that exploiting every functional group adequately in substrates to obtain value-added chemicals.

Bellows are the key structures that compensate for and absorb the temperature-dependent displacement of a gas insulated switchgear (GIS) shell. It is of great engineering value to master the relationship between the temperature-dependent displacement behavior and various influencing factors. Based on the analysis of the influencing factors of the temperature variation displacement compensation ability of the GIS bellows, a bellows model was established. By coupling it with a shell having different degrees of bending through two layout methods, finite element simulation was carried out based on ABAQUS software to obtain the regular relationship between the temperature variation displacement compensation behavior of the bellows and various influencing factors. The results of the case study show that the temperature change displacement compensation ability of the bellows is most significantly affected by their own structural size. Reducing the wall thickness and increasing the wave height of the bellows can effectively improve the temperature change displacement compensation ability of the bellows and reduce the stress concentration in the compensation process. The change in the GIS shell shape is the second-most important influence; when the sliding support base of the bus barrel is lower than the fixed support base, the amount of temperature change displacement compensation of the bellows increases and the compensation capacity decreases, and, on the contrary, the temperature compensation capacity increases. Within the operating temperature range, the compensation ability of bellows with a distributed arrangement is better than that of a centralized arrangement, and can alleviate the initial deformation caused by gravity and gas pressure in GIS equipment.

Yellow River sediment is the potential resource for saline–sodic soil reclamation. Experiments of one-dimensional soil columns were conducted to investigate the upward and downward soil water transportation characteristics for saline–sodic soil mixed with different sediment addition (0, 10, 20 kg/m2 in the top 20 cm layer). The saturated hydraulic conductivity, ratio of macroporosity, cumulative capillary adsorption and infiltration rate all increased with the increase in sediment addition. No significant differences were detected for both the initial capillary rise rate and the initial infiltration rate for the upward and downward water transportation treatments, respectively. The average adsorption and infiltration rates showed an increasing trend with the increased sediment addition. The initial and average infiltration rates were higher than the initial capillary rise rate and average adsorption rates. The Philip model seems the optimal choice for the dynamic simulation of both upward and downward soil water transportation. The results may provide useful information for soil salinization amelioration.

Down fiber assembly is a heterogeneous and hierarchical system whose structure can be hardly characterized. At the meantime, its thermal property is valuable for usage, it would guide design if the correlation between thermal performance and structure can be understood. In this paper, fractal approach was introduced to characterize the microstructure of down fiber assembly. Fractal dimensions of fiber assemblies are calculated by box-counting method and are found to be positively correlated with basic structural parameters such as fiber mass and volume fraction. Meanwhile, the results indicate that increasing fractal dimension will lead to an enhancement of thermal insulation performance.

Reducing crop luxury transpiration is an important step in improving water productivity; water shortage regions are potential hotspots for studying physiological water conservation. This study investigated the amount of luxury transpiration in winter wheat and its responses to different irrigation treatments in North China Plain. The results showed that luxury transpiration existed and increased with growth of winter wheat and after rainfall. In each sampling day, the amount of luxury transpiration under full irrigation was significantly higher than that under deficit irrigation. The average amount of luxury transpiration was 258.87 g/m2 under full irrigation, and 125.18 g/m2 under deficit irrigation during the experimental period. Although the amount of luxury transpiration was 2.09-fold higher under full irrigation than that in deficit irrigation, the water loss ratio due to luxury transpiration in deficit irrigation (8.13%) was significantly higher than that in full irrigation (6.75%). Furthermore, the ratio between luxury transpiration amount and crop daily transpiration was revealed in all sampling dates. Therefore, deficit irrigation should be generalized in the water shortage area, because it can save irrigation water and reduce the amount of luxury transpiration. Full irrigation should be carried out in the water abundant region mainly for higher production.

The membrane electrode assembly was prepared by a catalyst coated membrane (CCM) with an effective active area of 10 × 10 cm2 in this work. Porous titanium plates with different diameters were used as anode collectors to study the polarization curve and electrochemical impedance spectroscopy (EIS) of the electrolyzer. The results show that the pore size of a porous titanium plate on the anode side has a significant effect on the performance of the electrolyzer. The best cell performance was obtained when the median diameter of the anode titanium plate was 12.3 um. When the current density is 1 A/cm2, the battery voltage is 2.253 V.

Hydrogen production with a proton exchange membrane (PEM)electrolyzer utilized with renewable energy power is considered to be an efficient and clean green technique, but the poor oxygen evolution performance results in high energy consumption and low efficiency. In this work, a strategy is reported for the construction of a support network of the anodic catalyst layer to simultaneously ameliorate its sluggish reaction kinetics and mass transport in order to realize highly efficient hydrogen production of the PEM electrolyzer. After in situ synthesis of IrO2 nanoparticles on N–doped TiO2 nanofibers, the as–prepared IrO2/N–TiO2 electrode shows substantially enhanced Ir utilization and accelerated mass transport, consequently decreasing the corresponding cell potential of 107 mV relative to pure IrO2 at 2 A cm−2. The enhanced activity of IrO2/N–TiO2 could be due to the fact that the N–TiO2 nanofiber support can form a porous network, endowing IrO2/N–TiO2 with a large reactive contact interface and favorable mass transfer characters. The strategy in this work supplies a pathway to develop high–efficiency interfacial reaction materials for diverse applications.

The micromorphology of fillers plays an important role in tribological and mechanical properties of polymer matrices. In this work, a TiO2-decorated Ti2C3 (TiO2/Ti3C2) composite particle with unique micro-nano morphology was engineered to improve the tribological and thermo-mechanical properties of epoxy resin. The TiO2/Ti3C2 were synthesized by hydrothermal growth of TiO2 nanodots onto the surface of accordion-like Ti3C2 microparticles, and three different decoration degrees (low, medium, high density) of TiO2/Ti3C2 were prepared by regulating the concentration of TiO2 precursor solution. Tribological test results indicated that the incorporation of TiO2/Ti3C2 can effectively improve the wear rate of epoxy resin. Among them, the medium density TiO2/Ti3C2/epoxy nanocomposites gained a minimum wear rate. This may be ascribed by the moderate TiO2 nanodot protuberances on the Ti3C2 surface induced a strong mechanical interlock effect between medium-density TiO2/Ti3C2 and the epoxy matrix, which can bear a higher normal shear stress during sliding friction. The morphologies of worn surfaces and wear debris revealed that the wear form was gradually transformed from fatigue wear in neat epoxy to abrasive wear in TiO2/Ti3C2/epoxy nanocomposites. Moreover, the results of thermo-mechanical property indicated that incorporation of TiO2/Ti3C2 also effectively improved the storage modulus and glass transition temperature of epoxy resin.

Soil salinization adversely affects agricultural productivity. Mitigating the adverse effects of salinity represents a current major challenge for agricultural researchers worldwide. The effects of exogenously applied glycine betaine (GB) and salicylic acid (SA) on mitigating sodium toxicity and improving the growth of cotton seedlings subjected to salt stress remain unclear. The treatments in a phytotron included a control (CK, exogenously untreated, non-saline), two NaCl conditions (0 and 150 mM), four exogenous GB concentrations (0, 2.5, 5.0, and 7.5 mM), and four exogenous SA concentrations (0, 1.0, 1.5, and 2.0 mM). The shoot and roots exposed to 150 mM NaCl without supplementation had significantly higher Na+ and reduced K+, Ca2+, and Mg2+ contents, along with lowered biomass, compared with those of CK. Under NaCl stress, exogenous GB and SA at all concentrations substantially inversed these trends by improving ion uptake regulation and biomass accumulation compared with NaCl stress alone. Supplementation with 5.0 mM GB and with 1.0 mM SA under NaCl stress were the most effective conditions for mitigating Na+ toxicity and enhancing biomass accumulation. NaCl stress had a negative effect on plant growth parameters, including plant height, leaf area, leaf water potential, and total nitrogen (N) in the shoot and roots, which were improved by supplementation with 5.0 mM GB or 1.0 mM SA. Supplementation with 5.0 mM exogenous GB was more effective in controlling the percentage loss of conductivity (PLC) under NaCl stress.

During four consecutive growing seasons (2014–2018), field experiments were conducted in the North China to determine winter wheat production function. The field experiments were carried out using winter wheat subjected to four N levels (N120, N180, N240, and N300) and three irrigation levels (If, I0.8f, and I0.6f). The main aims were to characterize winter wheat productivity, drought response factor Ky, and the winter wheat grain yield production functions in relation to water supply under the different N fertilizer levels. The amount of water supply (rain + irrigation) were 326–434, 333–441, 384–492, and 332–440 mm in 2014–2015, 2015–2016, 2016–2017, and 2017–2018 growing seasons, respectively. Similarly, the values of ETa (including the contribution from soil water storage) were 413–466, 384–468, 401–466, and 417–467 mm in 2014–2015, 2015–2016, 2016–2017, and 2017–2018, respectively. ETa increased as the amount of irrigation increased. The average values of If, I0.8f, and I0.6f over the four growing seasons were 459–465, 432–446, and 404–413 mm, respectively. For the same amount of irrigation, there was only small difference in ETa among different nitrogen levels; for the three irrigation levels, the values of ETa in N120, N180, N240, and N300 ranged from 384 to 466, 384 to 466, 385 to 467, and 407 to 468 mm, respectively. Water productivity values ranged from 1.69 to 2.50 kg m−3 for (rain + irrigation) and 1.45 to 2.05 kg·m−3 for ETa. The Ky linearly decreased with the increase in nitrogen amount, and the values of r were greater than 0.92. The values of Ky for winter wheat in N120, N180, N240, and N300 were 1.54, 1.41, 1.28, and 1.25, respectively. The mean value of Ky for winter wheat over the three irrigation levels and the four nitrogen levels was 1.37 (r = 0.95). In summary, to gain higher grain yield and WUE, optimal combination of N fertilizer of 180–240 kg·ha−1 and irrigation quota of 36–45 mm per irrigation should be applied for winter wheat with drip fertigation in the North China Plain.

Mechanical properties, such as residual stress, micro-hardness and fatigue performance, of the Ti-5Al-4Mo-4Cr-2Sn-2Zr titanium alloy were improved via the laser peening without coating (LPwC) with a water-penetrable wavelength of 532 nm and pulse duration of 10 ns. In this paper, three kinds of laser energy, namely 85, 110 and 160 mJ were used to process the samples. The titanium alloy samples were also peened with different impact times (1, 3 or 5 impacts) at the energy of 85 mJ. The micro-hardness and residual stress distribution results provided that LPwC can introduce compressive residual stress (CRS) and also induce hardening of the target materials. Further, micro-hardness and CRS showed the increasing trends when the laser impact times increased. However, the CRS and micro-hardness decreased while the laser energy increased from 110 to 160 mJ, which was attributed to the dynamic equilibrium between the thermal and mechanical effects of LPwC. High cycle fatigue strength of the titanium alloy was significantly improved from 360 to 490.3 MPa after three impacts LPwC. The strengthening mechanism of fatigue strength subjected to LPwC was a combined effect between the laser-induced CRS and the high-density dislocations.

Low cost fabrication of water treatment polymer materials directly from biomass resources is urgently needed in recent days. Herein, a compressive alginate sponge (AS) is prepared from seaweed biomass resources through a green two-step lyophilization method. This material is much different from conventional oven-, air-, vacuum-dried alginate-based adsorbents, which show limitations of shrinkage, rigidness, tight nonporous structure and restricted ions diffusion, hindering its practical applications, and was used to efficiently remove methylene blue (MB), a main colorful contaminant in dye manufacturing, from wastewater. The batch adsorption studies are carried out to determine the impact of pH, contact time and concentration of dye on the adsorption process. The maximum adsorption capacity can be obtained at 1279 mg g−1, and the shape-moldable AS can be facilely utilized as a fixed-bed absorption column, providing an efficient approach for continuous removal of MB within a short time. It is also important that such a compressive AS can be regenerated by a simple squeezing method while retaining about 70% capacity for more than ten cycles, which is convenient to be reused in practical water treatment. Compressive AS demonstrates its merits of high capability, large efficiency and easy to recycle as well as low cost resources, indicating widespread potentials for application in dye contaminant control regarding environmental protection.

Collecting accurate real-time soil moisture data in crop root zones is the foundation of automated precision irrigation systems. Soil moisture sensors (SMSs) have been used to monitor soil water content (SWC) in crop fields for a long time; however, there is no generally accepted guideline for determining optimal number and placement of soil moisture sensors in the soil profile. In order to study adequate positioning for the installation of soil moisture sensors in the soil profile, six years of field experiments were carried out in North China Plain (NCP). Soil water content was measured using the gravimetric method every 7 to 10 days during six growing seasons of winter wheat (Triticum aestivum L), and root distribution was measured using a soil core method during the key periods of winter wheat growth. The results from the experimental data analysis show that SWC at different depths had a high linear correlation. In addition, the values of correlation coefficients decreased with increasing soil depth; the coefficient of variation (CV) of SWC was higher in the surface layers than in the deeper layers (depths were 0⁻40 cm, 0⁻60 cm, and 0⁻100 cm during the early, middle, and last stages of winter wheat, respectively); wheat roots were mainly distributed in the surface layer. According to an analysis of CV for SWC and root distribution, the depths of planned wetted layers were determined to be 0⁻40 cm, 0⁻60 cm, and 0⁻100 cm during the sowing to reviving stages (the early stage of winter wheat), returning green and jointing stages (the middle stage of winter wheat), and heading to maturity stage (the last stage of winter wheat), respectively. The correlation and R-cluster analyses of SWC at different layers in the soil profile showed that SMSs should be installed 10 and 30 cm below the soil surface during the winter wheat growing season. The linear regression model can be built using SWC at depths of 10 and 30 cm to predict total average SWC in the soil profile. The results of validation showed that the developed model provided reliable estimates of total average SWC in the planned wetted layer. In brief, this study suggests that suitable positioning of soil moisture sensors is at depths of 10 and 30 cm below the soil surface.

The paper presents an overview of the traditional methods to obtain wind parameters such as wind speed, wind direction and air density. After analyzing wind turbines’ arrangements and communication characteristics and the correlation of operation data between wind turbines, the paper proposes a novel recombination-sensing method route of “measuring–correlating–sharing–predicting–verifying” (MCSPV) and explores its feasibility. The analysis undertaken in the paper shows that the wind speed and wind direction instrument fixed on the wind turbine nacelle is simple and economical. However, it performs in-process measurement, which restricts the control optimization of wind turbines. The light detection and ranging (LIDAR) technology which is accurate and fast, ensures an early and super short-time sensing of wind speed and wind direction but it is costly. The wind parameter predictive perception method can predict wind speed and wind power at multiple time scales statistically, but it has limited significance for the control of the action of wind turbines. None of the traditional wind parameter-sensing methods have ever succeeded in air density sensing. The MCSPV recombination sensing method is feasible, both theoretically and in engineering, for realizing the efficient and accurate sensing and obtaining of such parameters as wind speed, wind direction and air density aimed at the control of wind turbines.

The accurate calculation and characteristic analysis of wind speed correlation (WSC) is the basis of wind farm equivalent modeling, wind power prediction and other advanced applications. It is well known that the accurate calculation of WSC depends on the quality of the raw data, and the WSC of wind turbines is related to spatial, time and meteorological conditions. However, the researches on the statistical analysis of time/meteorological WSC characteristics and the original data quality improvement for WSC calculation are rarely carried out. This paper reviews and redefines the concept and connotation of spatial, time and meteorological WSC. On this basis, a general process is proposed for WSC calculation including data classification, extraction and cleaning. Then the WSC characteristics between wind turbines are analyzed from time and meteorological dimensions based on the actual operation data. In addition, the influence of time WSC and meteorological WSC on wind turbine equivalent modeling and wind power prediction was discussed. The results of case study shows that the proposed general WSC calculation process is feasible and effective; the WSC for different time scales, wind speed ranges and wind directions varies greatly; the spatial WSC cannot characterize the time variability and directionality of the WSC. And the time and meteorological WSC characteristics are of great engineering value to improve the wind turbine equivalent modeling and wind power prediction accuracy, the influence of time scale and meteorological conditions should be considered in the applications of WSC.