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Abstract Evapotranspiration (ET) is critical to surface water dynamics. Effective water resource management necessitates an accurate ET estimation. In the Yellow River Basin China, a study area, cutting-edge technologies are needed to improve large-scale ET estimates. This study estimates ET using GSEBAL, an advanced ET estimation algorithm. Google Earth Engine integrates the surface energy balance model-based GSEBAL. The technique includes the collection, preparation, and calculation of ET using Landsat imagery and ERA5-Land meteorological data from 1990 to 2020. The study examined satellite LST, albedo, and NDVI data. The GSEBAL model calculates soil heat flow, net radiation, and sensible heat flux. The study tested the GSEBAL model utilizing essential ET datasets such as ECOSTRESS, MOD16, and SSEBop. The study showed that the model effectively predicted daily and seasonal ET variations in different climates. Root mean squared error, bias, and Pearson's correlation coefficient verified the model's reliability. The study also analyzed land use and land cover (LULC) over 30 years using Random Forest classifiers. In the 1990–2020 YRBC ET, land use changes affect ET rates annually and seasonally. The study area experiences changes in LST, NDVI, and LULC. Maximum ET values rose from 214.217 mm in 1990 to 234.891 mm in 2000. The pattern flipped in 2020, decreasing to 221.456 mm. In 2010, Summer had the highest ET, 484.455 mm. 2020 spring ET is 314.727 mm. Low ET decreased from 24.652 mm in 1990 to 18.2 mm in 2020, reducing water loss. Fall ET peaks at 24.9 mm in 2020; winter ET is 18.75 mm.

【Objective】 The ecological functions of a river are manifold; and how to determine river flow rates which are ecologically sustainable is important but not trivial. In this paper, we proposed a new approach to model river habitat. 【Method】 The model is based on multiple indicator species and considers their competition as well as the consequence for growth of individual species. The model is constructed based on the fuzzy logic method to establish the quantitative relationship between river habitat quality and runoff conditions. We applied the model to the Xinyang section of the Shihe River. 【Result】 The sustainable ecological water flow in this section of the river calculated by the model is 160~260 m3/s, and the minimum ecological flow rate is 60 m3/s. The result interval is stricter than that calculated from the single indicator species model using crucian carp as the indicator. 【Conclusion】 Multiple indicator species model we proposed for determining ecologically sustainable river flow is robust and accurate. It can be used for designing sustainable development and utilization of river water resources.

The variations in the reference evapotranspiration (ET0) are closely related to meteorological factors. The purpose of this study is to explore the relationships between the meteorological factors and the ET0. Based on meteorological data from 26 meteorological stations in the Yiluo River Basin (YLRB) and its surrounding areas from 1958 to 2020, in this study, the temporal and spatial variations and driving factors of the ET0 in the YLRB are investigated. The results are as follows. Spatially, the annual ET0 decreases from the northeast to the southwest in the YLRB. Temporally, the annual ET0 exhibits a fluctuating decreasing trend rather than a monotonic decreasing trend during the entire period. The trend of the ET0 contains two mutation points, in 1972 and 1994. Thus, the research period can be divided into three periods. It is concluded that the variations in the ET0 are the most sensitive to the relative humidity, but the driving factor that contributes the most to the variations in the ET0 is the wind speed. The driving factors are closely related to the rates of relative change of the meteorological factors.

The machining accuracy of cycloidal tooth surface is the key factor affecting the motion performance of RV reducer,and the reverse correction of grinding parameters according to the data of tooth surface error detection is an important link in the manufacturing process of the cycloidal gear. Through the analysis of the cycloidal gear generating grinding principle,the complex motion relationship between the grinding wheel and the cycloidal gear is clarified and the model of the movement relation of the cycloidal tooth surface is established.Besides,based on the gear meshing theory and the principle of space coordinate conversion,the mathematical expression of the cycloidal gear theoretical tooth surface and the normal vector with the parameters of the grinding adjustment are deduced,which provides a theoretical basis for correcting the tooth profile error after testing.Then according to the cycloidal generating grinding model,the influence of main grinding parameters on the tooth surface error is discussed. Finally,a comparison is made with the cycloidal tooth profile obtained by generation principle,which proves that the equation and its establishment method is correct. It can not only provide the necessary theoretical data for the machining error detection of the cycloidal gear,but also have important significance for the correction of the grinding parameters and the accuracy improvement of the cycloidal tooth surface.

In order to study the vibration characteristic of vertical column of cycloid gear grinder,the three-dimensional solid model is established based on the vertical column component of cycloid gear grinder,and the pre-stress modal analysis is carried out based on the finite elements software ANSYS simulation. The natural frequency and corresponding vibration mode of the component are obtained. To study the real vibration characteristic of the vertical column,the vibration test platform is set up. Then the time-frequency characteristic of the collected data are analyzed,and the vibration mechanism of the vertical column is explored. The experimental results show that the vertical column is better in the low order frequency characteristic,and compared with the free working conditions under the same direction,the maximum vibration amplitude of the corresponding peak at the same frequency is not more than 4. 7%. Finally,the rationalization proposal for design and optimization of the vertical column are put forward from the vibration.

Poly(acrylamide)-multiwalled carbon nanotubes (PAAm-MWNTs) hybrid hydrogels were prepared through the radiation-induced polymerization and crosslinking of the aqueous solution of acrylamide and well-dispersed MWNTs for the first time. The PAAm gels obtained by the radiation-induced polymerization and cosslinking showed very high mechanical strengths, and the PAAm-MWNTs hybrid hydrogels had improved mechanical properties compared with the PAAm gels, and hence the PAAm-MWNTs hybrid hydrogels showed extremely high compressive and tensile strengths. The hybrid hydrogels with water contents more than 80 wt.% usually did not fracture even at compressive strengths close to or even more than 60 MPa and strains more than 97%. And the hybrid hydrogels had very high elongations (more than 2000% in some cases), especially when the water content was high. The tensile strengths were in sub-MPa. The hybrid PAAm-MWNTs hydrogel is one of the strongest hydrogel even made.

Inspired by the superhydrophobicity of juicy peach surface, on which microscale hairs are standing vertically to the surface plane, an extremely simple, inexpensive physical method is developed for fabrication of superhydrophobic polyolefin surfaces over large areas. This method includes three steps: abrasive paper scraping, adhesive tape bonding and 90° peeling. Scraping increases the roughness and enhence water contact angles (CAs) on polyolefin surfaces. It increases more when the scraped surface are bonded with adhesive types and then then 90° peeled. The CA variation depends on the types of polyolefin and abrasive paper. Superhydrophobic lowdensity polyethylene (LDPE), high-density polyethylene (HDPE) and polypropylene (PP) surfaces (CA>150°) are obtained and they all exhibit very low adhesive force and high resistance to strong acids and bases.

Based on the geometric principles of the 5-axis CNC forming grinding and machine kinematics principle,the line speed of wheel at any points is deduced.According to the traditional plane grinding force model,these relationships are used that molding grinding involute length is approximately equal to the width of the plane grinding wheel,the diameter of wheel in contact with the tooth surface is approximately equal to the diameter of the plane grinding wheel,the wheel feed amount is approximately equal to the grinding surface grinding depth.So the grinding force model are established,the grinding force simulation program is composed and the experimental schemes are design,lastly this grinding force formula can guarantee a certain precision.

The structural and functional complexity of multicellular biological systems, such as the brain, are beyond the reach of human design or assembly capabilities. Cells in living organisms may be recruited to construct synthetic materials or structures if treated as anatomically defined compartments for specific chemistry, harnessing biology for the assembly of complex functional structures. By integrating engineered-enzyme targeting and polymer chemistry, we genetically instructed specific living neurons to guide chemical synthesis of electrically functional (conductive or insulating) polymers at the plasma membrane. Electrophysiological and behavioral analyses confirmed that rationally designed, genetically targeted assembly of functional polymers not only preserved neuronal viability but also achieved remodeling of membrane properties and modulated cell type-specific behaviors in freely moving animals. This approach may enable the creation of diverse, complex, and functional structures and materials within living systems.

Evapotranspiration (ET) plays a crucial role in the hydrological cycle, significantly impacting agricultural productivity and water resource management, particularly in water-scarce areas. This study explores the effects of key climate variables temperature, precipitation, solar radiation, wind speed, and humidity on ET from 2000 to 2020, with forecasts extended to 2030. Advanced data preprocessing techniques, including Yeo-Johnson and Box-Cox transformations, Savitzky–Golay smoothing, and outlier elimination, were applied to improve data quality. Datasets from MODIS, TRMM, GLDAS, and ERA5 were utilized to enhance model accuracy. The predictive performance of various time series forecasting models, including Prophet, SARIMA, STL + ARIMA, TBATS, ARIMAX, and ETS, was systematically evaluated. This study also introduces novel algorithms for Explainable AI (XAI) and SHAP (SHapley Additive exPlanations), enhancing the interpretability of model predictions and improving understanding of how climate variables affect ET. This comprehensive methodology not only accurately forecasts ET but also offers a transparent approach to understanding climatic effects on ET. The results indicate that Prophet and ETS models demonstrate superior prediction accuracy compared to other models. The ETS model achieved the lowest Mean Absolute Error (MAE) values of 0.60 for precipitation, 0.51 for wind speed, and 0.48 for solar radiation. Prophet excelled with the lowest Root Mean Squared Error (RMSE) values of 0.62 for solar radiation, 0.67 for wind speed, and 0.74 for precipitation. SHAP analysis indicates that temperature has the strongest impact on ET predictions, with SHAP values ranging from −1.5 to 1.0, followed by wind speed (−0.75 to 0.75) and solar radiation (−0.5 to 0.5). [ABSTRACT FROM AUTHOR]

Soil available nutrients (SANs) can be rapidly converted, absorbed, and utilized by crops. The study of the spatial distribution and variation of SANs, as well as their response to environmental factors, is crucial for precision fertilization and soil ecosystem function regulation. In this study, 220 soil surface-layer samples (0–20 cm) were collected in 2019 from loquat orchards in the mid-low mountain hilly areas of central China to explore the spatial distribution and variation of SANs, as well as the effects of environmental factors (including the topography, vegetation index, soil property, and climate) on SANs, using a path analysis model. The results showed that the available potassium (AK) and ammonium nitrogen (AN) levels exhibited a moderate average content, which was 123.14 mg·kg−1 and 119.03 mg·kg−1, respectively, whereas available phosphorus (AP) levels displayed a high average content (26.78 mg·kg−1), and all three SANs showed an uneven spatial distributions. The nugget effect values of AK and AN ranged from 25% to 75%, indicating moderate spatial variation, and those of AP were <25%, suggesting high spatial variation. Furthermore, the mean annual precipitation (MAP) had a direct positive effect on AK levels, while slope had an indirect effect on AK levels through the ratio vegetation index (RVI), suggesting that precipitation had greater impact on AK levels than topography. Soil erosion had a direct negative effect on AP and AN levels, accelerating the loss of SANs. The MAP and soil type (ST) directly affected soil AN content. Specifically, sufficient precipitation and fine soil facilitated the storage and conversion of AN in soil. Taken together, our path analysis indicated that all the four categories of environmental factors had direct or indirect effects on SANs, and our geostatistical analysis revealed the spatial distribution and variation law of SANs in the study area. Our findings offer a theoretical basis and valuable references for achieving precision fertilization in orchards and improving loquat yield and quality. [ABSTRACT FROM AUTHOR]