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Yb-doped Y2O3 stabilized ZrO2 (YbYSZ) coatings, developed through solution precursor plasma spraying (SPPS), are engineered to resist calcium–magnesium–alumino–silicate (CMAS) infiltration by leveraging their unique micro-nano structures. This provides superior anti-wetting properties, crucial for preventing CMAS penetration at high temperatures. The investigation focused on the structural and compositional changes in YbYSZ-SPPS coatings subjected to prolonged thermal exposure at 1300 °C. Results indicate that while the coatings undergo significant sintering, leading to densification and microstructural evolution, the elemental composition and phase stability remain largely intact after up to 8 h of heat treatment. Despite some reduction in CMAS resistance, the coatings maintained their overall protective performance, demonstrating the potential of SPPS coatings for long-term use in high-temperature environments where CMAS infiltration is a concern. These findings contribute to the development of more durable TBCs for advanced thermal protection applications. [ABSTRACT FROM AUTHOR]

A novel axially chiral all-hydrocarbon cyclo[7] (1,3-(4,6-dimethyl)benzene (CDMB-7) was designed and synthesized using atroposelective[2 + 5] cyclization through Suzuki–Miyaura coupling. CDMB-7 adopts an irregular bowl-like shape with C2 symmetry and exhibits two diastereoisomers in its crystallographic structure. The conformational isomers of CDMB-7 racemates remain stable at high temperatures (393 K). High-performance liquid chromatography (HPLC) confirmed that a single chiral isomer will spontaneously undergo racemization within 30 min at room temperature. This finding opens up possibilities for achieving adaptive chirality in all-hydrocarbon cyclo[7] m-benzene macrocycles. [ABSTRACT FROM AUTHOR]

Thermal barrier coatings (TBCs) play a crucial role in enhancing the operating temperature of key equipment. However, when TBCs are sprayed on the internal surface of these components, there are issues related to the imperfect internal diameter atmospheric plasma spray (ID-APS) process and the unsatisfactory performance of TBCs in internal holes. Yttria-stabilized zirconia (YSZ), YSZ + Gadolinium zirconate (GZ) and YSZ + tantalate (RETaO4) TBCs were prepared using the SM F210 ID-APS gun. The thermal shock and particle erosion resistance of the coatings were compared, and the relationship between the structure and properties was investigated. The results show that the hardness, fracture toughness and erosion resistance of the three coatings are the largest in the YSZ coating and the smallest in the GZ coating. YSZ coating also has the best thermal shock resistance. These research findings have important guiding significance for the improvement of the ID-APS process. [ABSTRACT FROM AUTHOR]

The factors influencing precipitation in western China are quite complex, which increases the difficulty in determining accurate predictors. Hence, this paper models the monthly measured precipitation data from 240 meteorological stations in mainland China and the precipitation data from the European Centre for Medium-Range Weather Forecasts and the National Climate Centre and employs 88 atmospheric circulation indices to develop a precipitation prediction scheme. Specifically, a high-quality grid-point field is created by fusing and revising the precipitation data from multiple sources. This field is combined with the Empirical Orthogonal Function decomposition and the causal information flow. Next, the best predictors are screened through Empirical Orthogonal Function decomposition and causal information flow, and a data-driven precipitation prediction model is established using a Back Propagation Neural Network and a Random Forest algorithm to conduct the 1-month, 3-month, and 6-month precipitation predictions. The results show that: The machine learning-based precipitation prediction model has high accuracy and is generally able to predict the precipitation trend in the western region better. The Random Forest algorithm significantly outperforms the Back Propagation Neural Network algorithm in the prediction of the three starting times, and the prediction ability of both models gradually decreases as the starting time increases. Compared with the 2022 flood season prediction scores of the Institute of Atmospheric Sciences of the Chinese Academy of Sciences, the model improves the prediction of 1-month and 3-month precipitation in the western region and provides a new idea for the short-term climate prediction of precipitation in western China. [ABSTRACT FROM AUTHOR]

The implementation of the "Returning Farmland to Forest" project in the loess hilly region of China has led to the establishment of large-scale economic forests, which have become the dominant industry driving local economic development. However, the region faces challenges such as drought, water shortages, and an uneven distribution of precipitation, which have a severe impact on the growth of economic forests, including jujube trees. Water stress significantly reduces yield and efficiency, posing a threat to the sustainable and healthy development of jujube ecological and economic forests. Therefore, this study aimed to address these issues by implementing straw mulching (SM) and jujube branch mulching (BM) measures in the mountainous jujube economic forests. Through long-term monitoring and statistical analysis, the study investigated the effects of different mulching treatments on soil moisture and soil temperature. The research findings reveal that both SM and BM significantly increased soil moisture in the 0–280 cm soil layer during the jujube growing season (p < 0.05). In both normal precipitation (2014) and drought (2015) years, SM increased average soil moisture content by 5.10% and 4.60%, respectively, compared to the uncovered treatment (CK). SM also had a positive impact on the soil moisture content in each layer of the soil profile. However, BM only increased soil moisture content in the 40–100 cm and 220–280 cm soil layers. Additionally, SM and BM reduced the variation of soil moisture, with SM showing a more significant effect in regulating soil moisture and achieving more stable moisture levels. During the jujube growing seasons in 2014 and 2015, SM and BM decreased soil temperature in the 0–10 cm soil layer. The temperature difference compared to CK decreased with increasing soil depth. SM had an overcooling effect, while BM reduced the temperature before the fruit expansion period and maintained warmth afterward. Both SM and BM also reduced the daily range and variation range of soil temperature, with SM having a more pronounced effect. The temperature of the 0–20 cm soil layer exhibited the strongest correlation with air temperature, and SM showed the weakest response. In conclusion, adopting straw mulching and jujube branch mulching in rain-fed jujube orchards in the loess hilly region not only saves materials and reduces costs but also contributes to water retention and temperature regulation. Straw mulching, in particular, plays a more significant role in moisture retention and temperature regulation and is advantageous for soil management in rain-fed jujube orchards. These research findings provide a scientific basis for optimizing water and heat management in orchards with limited water resources. [ABSTRACT FROM AUTHOR]

At present, some shortcomings of the research on coupling modeling of the oceanic front–sound field may need attention: (1) Most of the acoustic propagation simulation is based on ideal front models, but the application of investigated marine data is lacking. (2) Most studies focus on the acoustic field characteristics, with the influence of fronts on acoustic propagation, but few studies aim at the direct quantitative analysis of the performance of underwater acoustic detection in oceanic fronts. To deal with the above problems, based on the measured data in the northwest Pacific Ocean, here, we first design different sound source layout schemes and calculate sound field characteristics in the sub-Arctic front using the ray theory. Then, the cumulative detection probability model is built based on the active sonar equation to evaluate the efficiency of underwater detection. Finally, the detection probability is calculated and expressed by regionalization, and the influence of the sub-Arctic front on underwater detection is quantitatively analyzed. The results show that the sub-Arctic front can significantly affect the underwater acoustic detection. The sound source located in the front in the cold-water mass has a better detection performance, especially detecting towards cold water (horizontal detection range > 60 km). In contrast, the sound source located in the warm-water mass has a poor detection performance (horizontal detection range in shallow sea < 10 km). [ABSTRACT FROM AUTHOR]

The indefinite characteristics of gas–liquid two-phase flow limit the usage of aerated drip irrigation. Gas–liquid two-phase flow in a labyrinth channel was observed using a particle tracking velocimetry (PTV) technique in this study. The motion trajectory and velocity vector of large numbers of microbubbles were characterized and analyzed at 0.01, 0.02, 0.04 MPa inlet pressure and in three labyrinth channels with different geometries. The results indicated that bubbly flow was the typical flow pattern in a labyrinth channel, with slug flow occurring occasionally. Smooth and gliding motion trajectories of bubbles were observed in the mainstream zone, while twisted trajectories were seen in the vortex zone. Increasing the inlet pressure increased the number of bubbles and the trajectory length in the vortex zone. When the inlet pressure increased from 0.02 to 0.04 MPa, the 25th percentile of Rc-t (the Ratio of Circular path length in the vortex zone to the Total trajectory length for a single bubble) increased from 0 to 12.3%, 0 to 6.1%, and 0 to 5.2% for channels A, B, and C, respectively; the 75th percentile increased from 31.3% to 43.9%, 27.5% to 31.9%, and 18.7% to 22.3%. The velocity vectors of the bubbles showed position dependence. Bubbles with high speed were found in the mainstream zone with their directions parallel to the water flow direction. Bubbles with low speed were seen in the vortex zone, moving in all directions. With inlet pressure increased from 0.01 to 0.04 MPa, the mean instantaneous velocities of bubbles in channels A, B, and C are increased by 106.2%, 107.6%, and 116.6%, respectively. At 0.04 MPa, channel A has the longest path length and the highest instantaneous velocity of bubbles in the vortex zone among three channels, exhibiting the highest anti-clogging performance of the three channels. This study will help in the comprehensive understanding of gas–liquid two-phase flow in a labyrinth channel used for aerated drip irrigation. [ABSTRACT FROM AUTHOR]

Promoting the development of new energy vehicles is one of the important measures to ensure energy security and deal with global warming. Technological innovation is an inexhaustible driving force for the development of the new energy vehicle industry. This study considered listed enterprises in China's new energy vehicle industry as research samples and used the fixed effect model to study the impact of government subsidies on the quantity and quality of technological innovation in the new energy vehicle industry. The empirical results show that government subsidies have a significant positive impact on the quantity of technological innovation in the new energy vehicle industry; however, government subsidies have no significant impact on the quality of technological innovation. Government subsidies increase the quantity of technological innovation in the new energy vehicle industry by increasing R&D investment, mitigating financing constraints, and improving the external attention of enterprises. Compared to downstream enterprises in the industrial chain, government subsidies have a better incentive effect on the technological innovation of upstream enterprises, which increases the number of patents and enhances the quality of utility model patents. Government subsidies have a better effect on promoting the quantity of technological innovation in large enterprises. [ABSTRACT FROM AUTHOR]

Cosmopolitan agricultural herbivorous pests are provided with a wide range of potential hosts. Therefore, they have high carrying capacity, and can cause extremely severe damage in agroecosystems. Understanding the ecological mechanisms of their population dynamics, especially as they relate to large-scale meteorological variations and geographical landscape influences, can help us to reveal how they became such important pests. The oriental fruit moth, Grapholita molesta, is a typical example of a significant pest distributed on a large scale, which is capable of damaging fruit trees of economic value such as peach, apple, pear, etc. This pest not only occurs in China, but exists on all continents except Antarctica. In order to prevent major pests and diseases, a system of plant protection has been established gradually in peach orchards within the Modern Agro-industry Technology Research System in China (CARS) since 2009. In the system, we collected the monitoring data of G. molesta by using pheromone traps at 17 experimental stations, and then used the corresponding climate data (temperature and precipitation) to explore the link between climate factors using mixed models. The results show that both monthly mean temperature and precipitation had a significant positive correlation with the occurrence of G. molesta. Therefore, global warming with higher levels of precipitation may favor G. molesta, allowing it to outperform other potential pests at the population level in peach orchards, on a large scale. [ABSTRACT FROM AUTHOR]

The influence of different mulching measures on soil moisture, soil temperature, and crop growth was investigated during the jujube growing season in rain-fed jujube orchards using micro-plot experiments. The mulching treatments included clean tillage (CT, control treatment), jujube branches mulching (JBM), and white clover planting (WCP). The results revealed that: (1) The average soil moisture content of JBM was greater than that of CT by 3.76% and 2.34%, respectively, during the 2013 and 2014 jujube growth periods, and its soil water deficit was minimal in each soil layer from 0 to 70 cm. WCP had the greatest soil water deficit. The average soil moisture content of the 0–70 cm soil layer in WCP was 3.88% and 5.55% lower than that in CT during the 2013 and 2014 jujube growth seasons, respectively (p < 0.05). (2) JBM had the highest annual average soil moisture content in each soil layer from 0 to 70 cm, followed by CT, while WCP had the lowest. White clover and jujube competed for water in the 20–40 cm soil layer, and JBM had the lowest variation in soil moisture. (3) Mulching with jujube branches and planting white clover could both control the temperature of the 0–25 cm soil layer and narrow the daily temperature range, with JBM being the least affected by air temperature. (4) Jujube's leaf area index and stem diameter increase in JBM were both significantly greater than in CT and WCP. In conclusion, using pruned jujube branches as surface mulch is appropriate for rain-fed jujube orchards because it can preserve soil moisture, regulate soil temperature, and promote jujube growth. [ABSTRACT FROM AUTHOR]

In nature, fungal endophytes often have facultative endohyphal bacteria (FEB). Can a model plant pathogenic fungus have them, and does it affect their phenotype? We constructed a growth system/microcosm to allow an F. graminearum isolate to grow through natural soil and then re-isolated it on a gentamicin-containing medium, allowing endohyphal growth of bacteria while killing other bacteria. F. graminearum PH-1 labelled with a His1mCherry gene staining the fungal nuclei fluorescent red was used to confirm the re-isolation of the fungus. Most new re-isolates contained about 10 16SrRNA genes per fungal mCherry gene determined by qPCR. The F. graminearum + FEB holobiont isolates containing the bacteria were sub-cultured several times, and their bacterial contents were stable. Sequencing the bacterial 16SrRNA gene from several Fg-FEB holobiont isolates revealed endophytic bacteria known to be capable of nitrogen fixation. We tested the pathogenicity of one common Fg-FEB holobiont association, F. graminearum + Stenatrophomonas maltophilia, and found increased pathogenicity. The 16SrRNA gene load per fungal His1mCherry gene inside the wheat stayed the same as previously found in vitro. Finally, strong evidence was found for Fg-S. maltophilia symbiotic nitrogen fixation benefitting the fungus. [ABSTRACT FROM AUTHOR]

As an important part of the large-scale ecological restoration project of "Grain for Green", the planting area of jujube (Ziziphus jujuba) trees has increased significantly in the hilly region on the Loess Plateau of China, which aims to improve water and soil conservation and develop economic prospects of the region. Understanding the long-term effects of expanding orchards and the responses of soil water dynamics to drought are important for orchard management. Therefore, we use a space-for-time substitution to investigate the variations of plant-available water storage in returning cropland to orchards with different stand ages (2, 6, 10, and 15 years) in a normal year (NY2014, 442.1 mm rainfall) and the next year with low annual precipitation (DY2015, 388 mm rainfall). The results showed that the plant-available water storage in jujube orchards decreased with increasing stand age, and the trend was most obvious in the 60–180 cm layer. The mature stands (10 and 15 years) primarily absorbed soil water from the deep layer (180–300 cm) in DY2015, leading to negative values of plant-available water storage. The whole soil profiles were all subjected to severe water deficits in our study. The findings will help guide rain-fed orchard management in the loess hilly region of China and similar dryland regions. [ABSTRACT FROM AUTHOR]

Cellulose has attracted considerable attention as the most promising potential candidate raw material for the production of bio-based polymeric materials. In the last decade, significant progress has been made in the production of biopolymers based on different cellulose forms. In this study, cellulose was obtained in an innovative and environmentally friendly way, using boxwood powder. Crude cellulose was obtained by treating Buxus powder with an ethanol–acetic acid–water mixture. Refined cellulose was then obtained by treatment with an acidic sodium hypochlorite solution and alkaline hydrogen peroxide solution. The novel chemistry of cellulose prepared by this method promises to be not only green, but also highly desirable, because of its lower emissions and low cost. It is crucial for the future of the global polymer industry. The refined cellulose was subjected to a high-temperature hydrothermal treatment under two temperatures and time conditions, with temperature gradients of 120, 140, and 160 °C, and time gradients of 1, 2, and 3 h. The samples were subjected to infrared and thermogravimetric analyses. The cellulose undergoes dehydration and thermal degradation reactions during the heat treatment process, and the thermal stability of the residual is enhanced, compared with that of virgin cellulose. Between 120 and 140 °C, the hydroxyl and hypomethyl groups on the surface of cellulose are shed. Groups in the amorphous region of the polymer are the first to be shed. The dehydration reaction reduces the number of free hydroxyl groups on the surface of the cellulose molecules. The dehydration reaction was accelerated by an increase in temperature. Between 140 and 160 °C, the β-(1,4)-glycosidic bond begins to slowly break and some furans are generated. The structure of cellulose undergoes reorganization during thermal treatment. The thermal stability of the modified material is greater than that of untreated cellulose. [ABSTRACT FROM AUTHOR]

Insulator faults detection is an important task for high-voltage transmission line inspection. However, current methods often suffer from the lack of accuracy and robustness. Moreover, these methods can only detect one fault in the insulator string, but cannot detect a multi-fault. In this paper, a novel method is proposed for insulator one fault and multi-fault detection in UAV-based aerial images, the backgrounds of which usually contain much complex interference. The shapes of the insulators also vary obviously due to the changes in filming angle and distance. To reduce the impact of complex interference on insulator faults detection, we make full use of the deep neural network to distinguish between insulators and background interference. First of all, plenty of insulator aerial images with manually labelled ground-truth are collected to construct a standard insulator detection dataset 'InST_detection'. Secondly, a new convolutional network is proposed to obtain accurate insulator string positions in the aerial image. Finally, a novel fault detection method is proposed that can detect both insulator one fault and multi-fault in aerial images. Experimental results on a large number of aerial images show that our proposed method is more effective and efficient than the state-of-the-art insulator fault detection methods. [ABSTRACT FROM AUTHOR]

Water shortage is the main bottleneck restricting the sustainable development of rain-fed jujube (Ziziphus jujuba Mill.) orchards in the loess hilly region of China. Given the effect of mulching on soil moisture conservation, straw mulching (SM) and jujube branch mulching (BM) were applied to a rain-fed jujube orchard in this study. Soil moisture dynamics, soil water storage, water consumption, and soil moisture attenuation after typical rainfall under SM, BM, and clean tillage (CT) were studied. The results showed the following: (1) The 0–60 cm soil layer was the seasonal fluctuation layer of soil moisture under SM, BM, and CT in both the normal precipitation year and the dry year studied. The moisture contents of the 0–60, 60–160, and 160–280 cm soil layers under SM and BM were higher than that under CT in the three experimental years studied, and SM showed the most obvious effect of increasing soil moisture. (2) SM and BM showed a significant soil water storage effect in all of the jujube growth stages, and SM had a better water storage effect than BM. (3) SM reduced the amount of water consumption by 94.3, 60.8, and 121.3 mm compared to CT in the whole jujube growth period in 2014, 2015, and 2016, respectively. The amount of water consumption of BM decreased by 34.8 and 31.0 mm compared to that of CT in the whole growth period in 2014 and 2015, respectively. (4) CT had the maximum soil moisture loss rate under continuous drought after rainfall. The soil moisture loss rate of CT was above 37.3% on the eleventh day after typical rainfall in 2014, 2015, and 2016. With the extension of drought, the soil moisture loss rate under SM increased slowly. This study suggests that SM is the best mulching measure for rain-fed jujube orchards, and pruned jujube branches can also be used for in situ mulching to obtain a certain moisture conservation effect. [ABSTRACT FROM AUTHOR]

With the development of unmanned aerial vehicle (UAV) control technology, one of the recent trends in this research domain is to utilize UAVs to perform non-contact transmission line inspection. The RGB camera mounted on UAVs collects large numbers of images during the transmission line inspection, but most of them contain no critical components of transmission lines. Hence, it is a momentous task to adopt image classification algorithms to distinguish key images from all aerial images. In this work, we propose a novel classification method to remove redundant data and retain informative images. A novel transmission line scene dataset, namely TLS_dataset, is built to evaluate the classification performance of networks. Then, we propose a novel convolutional neural network (CNN), namely TL-Net, to classify transmission line scenes. In comparison to other typical deep learning networks, TL-Nets gain better classification accuracy and less memory consumption. The experimental results show that TL-Net101 gains 99.68% test accuracy on the TLS_dataset. [ABSTRACT FROM AUTHOR]

Insulator missing fault is a serious accident of high-voltage transmission lines, which can cause abnormal energy supply. Recently, a lot of vision-based methods are proposed for detecting an insulator missing fault in aerial images. However, these methods usually lack efficiency and robustness due to the effect of the complex background interferences in the aerial images. More importantly, most of these methods cannot address the insulator multi-fault detection. This paper proposes an unprecedented cascaded model to detect insulator multi-fault in the aerial images to solve the existing challenges. Firstly, a total of 764 images are adopted to create a novel insulator missing faults dataset 'IMF-detection'. Secondly, a new network is proposed to locate the insulator string from the complex background. Then, the located region that contains the insulator string is set to be an RoI (region of interest) region. Finally, the YOLO-v3 tiny network is trained and then used to detect the insulator missing faults in the RoI region. Experimental results and analysis validate that the proposed method is more efficient and robust than some previous works. Most importantly, the average running time of the proposed method is about 30ms, which demonstrates that it has the potential to be adopted for the on-line detection of insulator missing faults. [ABSTRACT FROM AUTHOR]