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• The actual performance of the cascading DWDD system is investigated. • The COP e,deh is related to the undertaken load of each dehumidification stage. • The partial COP e,deh decreases with the deepening of the dehumidification process. • Reducing the cooling temperature of CC-1 enhances the COP e,deh. • The low humidity bypass air is recommended to be applied as the regeneration air. The desiccant wheel deep dehumidification system in the lithium-ion battery manufacturing factory is significantly energy intensive, which substantially treats the process air from the ambient to the supply air state with a dew point temperature below −20 °C. On-site measurements were conducted in this study to investigate the actual performance of the deep dehumidification systems. The air treatment process and energy consumption during the operation were continuously monitored. The results reveal that the coefficient of performance of the dehumidification process of the systems ranges from 0.54 to 0.63 under basic winter conditions and ranges from 1.15 to 1.25 under basic summer conditions. The deep dehumidification processes of the systems are divided into multiple stages, and with the deepening of the process air humidity ratio from above 6 g/kg to below 0.3 g/kg, the partial energy efficiency of the treatment stages decreases. The efficient operational strategies are further elaborated for the improvement of the deep dehumidification system, including the proper match between the dehumidification gradient and the dehumidification stages, and the appropriate use of outlet process air with low humidity ratio as the regeneration air. The energy consumption of the cascading desiccant wheel dehumidification system can be reduced by lowering the cooling temperature of the cooling coil to undertake more latent load in the preliminary dehumidification stage. The effect of the bypass air state as the regeneration air is revealed, and the energy efficiency of the system is enhanced by up to 32 % by applying appropriate bypass air. This study offers guidance for the future design of the cascading desiccant wheel deep dehumidification system in similar applications. [ABSTRACT FROM AUTHOR]

• We investigated the effects of windbreaks on PM emissions from agricultural soil erosion. • There is little impact of windbreak on PM 1 and PM 2.5 reduction. • PM 10 concentrations can be reduced significantly by windbreaks. • The settling velocity of particles has an impact on the effects of windbreaks. Wind erosion from agricultural fields contributes substantial amounts of particulate matter (PM) in the form of dust to the atmosphere, with significant impacts on air quality and human health. Vegetation barriers affect particle transport via altering air flow, yet the impact of windbreaks on PM concentrations from agricultural soil erosion is still unknown. This study describes brief campaigns to explore the effects of windbreaks on PM concentrations in Zhangbei County, Heibei Province, China. Measurements were made in arable lands with windbreaks, of which the dominant tree species was Populus , following dust events from April to May, when the trees were without leaves. We selected windbreaks with different structures and measured PM concentrations at the windward and the leeward sides of the windbreaks, using high time-resolution measurements. The effects of windbreaks were quantified by calculating the PM concentration ratios in front of and behind the windbreaks. During dust events, the average value of maximum PM 10 emissions was 109.87 μg/m3, which was above the threshold established by the World Health Organization (WHO) for air quality. The PM 10 emissions increased with air temperature and wind speed. The highest PM 10 emission was observed at a relative air humidity of 20%. PM 1 and PM 2.5 concentrations were not lower behind the windbreak than in front of the windbreak in most of the events, while PM 10 concentrations could be reduced by an average of 27%. A significant increase in PM 2.5 /PM 10 by 56.86% behind the windbreak indicates the high efficiency of the windbreak to reduce PM 10 levels. Simply planting trees can, in some cases, increase downwind PM concentrations. Vegetation configuration and avoiding locating residential areas in the immediate lee of windbreaks should be considered when planning windbreaks. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The appropriate parameters of the SaltMod model were calibrated and validated. • The appropriate water management strategies were proposed. • Irrigation and drainage measures played a significant role in controlling salinity. • Results indicate that the proposed model is useful for soil salinity modeling. Abstract Soil salinity is considered the most serious factor that limits food security and sustainable development of irrigated agriculture productivity, especially in arid and semi-arid regions. Irrigation and drainage management play a critical role in soil water dynamics, soil desalinization, and crop growth and yield. This study was conducted to determine the changes caused by salinization on cultivated lands and salt wastelands in the long term given the present irrigation and drainage practices and under the different water management scenarios. Moreover, this study was aimed at developing appropriate management strategies to decrease the salt accumulation based on long-term simulation results. A SaltMod model was calibrated and validated using data from 2010 to 2016. Leaching efficiencies of F lr = 0.85 and F lx = 0.65 in the root and transition zones and natural drainage of 0.10 m/year were determined, thereby providing the optimal match between the observed and simulated values. Prediction results showed that the salinity of the cultivated land would exhibit slight decrease in the next 10 years under the current irrigation and drainage conditions. The proposed irrigation schemes were analyzed to improve the soil desalination effect in the long-term. Results indicated that autumn irrigation water was increased by approximately 10%–20%, and summer irrigation water was decreased by approximately 15% in the prospective 10 years (2016–2026) based on the present irrigation conditions. Furthermore, the soil salinity will decrease by approximately 1.06%–10.92%, and the total irrigation water will decrease by approximately 50–295 m3/ha, thereby possibly contributing to improved water saving and soil desalination. [ABSTRACT FROM AUTHOR]

Improving energy efficiency is a crucial aspect of building a sustainable smart city and, more broadly, relevant for improving environmental, economic, and social well-being. Non-intrusive load monitoring (NILM) is a computing technique that estimates energy consumption in real-time and helps raise energy awareness among users to facilitate energy management. Most NILM solutions are still a single machine approach and do not fit well in smart cities. This work proposes a model-agnostic hybrid federated learning framework to collaboratively train NILM models for city-wide energy-saving applications. The framework supports both centralised and decentralised training modes to provide a cluster-based, customisable and optimal learning solution for users. The proposed framework is evaluated on a real-world energy disaggregation dataset. The results show that all NILM models trained in our proposed framework outperform the locally trained ones in accuracy. The results also suggest that the NILM models trained in our framework are resistant to privacy leakage. [ABSTRACT FROM AUTHOR]

Highlights: [•] We proposed a method for short-term forecasting of reference evapotranspiration. [•] Temperature forecasts for 7-day horizons were used. [•] Accuracy of the proposed method was evaluated. [•] Errors were caused by errors in inputs and inherent defect of the employed model. [Copyright &y& Elsevier]

Seasonal freeze-thaw processes affect soil water migration and distribution, especially in semi-arid agricultural areas. These processes play an important role in mitigating harsh environmental conditions and wind erosion. Soil water content (SWC) and soil temperature (ST) were monitored at different depths (0–2 m) and investigated under freeze-thaw conditions from November 2018 to May 2019 in a semi-arid agro-pastoral region of northern China. The initial SWC was the main factor that affected the freeze-thaw process. During the freeze-thaw process, differences in soil thermal conductivity caused the soil to thaw faster than the freezing process, and the upper soil layer (0–60 cm) was significantly affected by temperature changes. Changes in the potential energy of water and pore pressure gradient caused the migration of soil water to the upper layer, which led to a slight decrease in SWC in each layer before ST dropped to the freezing point. The vertical migration distance of soil water exceeded 70 cm, and the SWC above a depth of 100 cm increased significantly, as water was mainly obtained from the soil layer below a depth of 200 cm. Soil compaction was reduced when affected by freeze-thaw processes and the soil particles were more fragmented, leading to wind erosion and dust events. Our results partially explain the occurrence of wind erosion in spring and provide a scientific basis for predicting soil water status and appropriate farmland management strategies. • Soil water content and soil temperature dynamic were quantified in farmland area. • Vertical migration distance of soil water exceeded 70 cm. • The initial SWC was the main factor that affected the freeze-thaw process. • Seasonal freeze-thaw processes will increase soil erodibility. [ABSTRACT FROM AUTHOR]

• Windbreaks can effectively reduce wind erosion on agricultural fields by 20 %. • Windbreaks can attenuate the spike of PM concentrations. • The dispersion of PM 10 to downwind areas could be reduced by windbreaks. • Windbreak have little impacts on dispersion of PM 2.5 and PM 1 concentrations. Particulate matter (PM) emissions from farmlands due to wind erosion have resulted in serious land degradation, air pollution, and human health problems. Although windbreaks have been traditionally planted on farmlands to reduce soil erosion, only a few studies examining wind erosion and PM emissions on farmlands utilizing windbreaks have been undertaken. In our study, the performance of windbreak patches and strips used for mitigating wind erosion and PM pollution were examined in-situ between 2017 and 2019. Soil loss and PM emissions from farmlands with and without windbreaks were measured using sediment traps, dust monitors and samplers during high wind events in a non-foliage period. Results indicated that soil loss in windbreak patches was 20 % lower than that on farmlands; compared to farmland, windbreak patches resulted in wind speed reductions of 27 % and 30 % at heights of 0.2 m and 2 m, respectively. The use of windbreak strips resulted in a reduction of PM 10 dispersion in downwind areas, recording a steeper decline of PM 10 concentrations in the open transect than in the vegetated transect. For PM 2.5 and PM 1 , the rate of decline was similar between the two transects. Windbreak strips were also recorded to reduce vertical PM 10 flux, with average values of 0.68 and -2.81 μg m−2 s-1 on the windward and leeward side, respectively. Shelter effects of windbreaks were highest when windbreak porosities were between 40 %–60 %, during which the shelter distance was between 7–9 times tree height. Results from this study can be used to assess wind erosion and PM emissions from farmlands with windbreaks, enabling suitable positioning of the windbreaks to maximize their effects. [ABSTRACT FROM AUTHOR]

• Shelter forests mortality and its relationship with precipitation and soil water content was quantified. • Lower mortality of poplar (<32%) above 230 mm (precipitation) and an SWC > 16.56%. • A threshold response was evident when precipitation was 60% of normal. • Wind speed, low temperature, and stand density had effects on the mortality of shelter forests. Shelter forests in the agricultural field are critical ecological barriers against harsh environmental conditions and agricultural soil erosion in northern China; however, shelter forests have been extensively degraded in the past decades. It is unknown how patterns of mortality of shelter forests relate to highly variable spatial precipitation and soil water content (SWC). Here, we explore the relationships of precipitation and SWC with the mortality of Populus simonii Carr (poplar) shelter forests in the semi-arid Bashang Plateau, northern China. Mortality of poplar shelter forests and its relationship with precipitation and SWC are spatially quantified in an area with an uneven distribution of precipitation by combining standard field plot measurements, precipitation, and SWC spatial distribution grid data. The mortality patterns of poplar shelter forests revealed threshold responses to precipitation and SWC, with lower mortality (<32%) above 230 mm (precipitation) and an SWC > 16.56%. Results indicate that a threshold response is evident when precipitation is 60% of the average precipitation. In addition, our results show that wind speed, low temperature, and stand density also had significant effects on the mortality of poplar shelter forests. Our results show how precipitation and SWC patterns within a region influence the mortality of poplar shelter forests. Moreover, this study reveals other factors influencing stand structure and landscape heterogeneity, which have been largely overlooked in previous studies. [ABSTRACT FROM AUTHOR]

Considering the difficulty of power supply for automatic observation equipment in the polar regions, this paper introduced a small standalone renewable energy system with wind–solar co-generation as the energy supply scheme. Mathematical models were given, including solar photovoltaic panels, wind turbines, solar irradiance, wind energy density, and renewable energy assessment. ERA-Interim atmospheric reanalysis data were used to evaluate solar energy resources, and the synergistic effect of wind–solar resources on renewable energy was also analyzed and discussed. The system composition of the small standalone renewable energy system was proposed in this study. This system deployed near Zhongshan Station was taken as the object of investigation to analyze the operation performance of each component of the system in different months, and the technical feasibility of the system has also been verified. The results showed that the wind–solar resources in the polar regions had a synergistic effect, which can provide an effective and feasible scheme for the power supply of automatic observation equipment. Through research and analysis, it was found that each component of the renewable energy system, including photovoltaic panels, wind turbines, and batteries, could meet the long-term power supply requirements of automatic observation regardless of the polar periods, polar day or polar night. This paper can not only provide theoretical and data support for the application of small independent renewable energy systems in the polar regions but also provide feasible solutions for clean energy supply of the systems and equipment for independent observation stations deployed in uninhabited islands and alpine regions. [ABSTRACT FROM AUTHOR]

• Excess salts from cultivated land accumulate in wasteland topsoil. • Coarse-textured, highly dispersed soils are distributed across the wasteland subsoil. • High K+, Mg2+/Na+ form macropores between cultivated land and wasteland. • Coarse-textured soil structure increases space for soil movement. Dry drainage is typically associated with groundwater and evapotranspiration as primary mechanisms, which ignores the horizontal water flow from cultivated land to salinized wasteland. Meanwhile, soil water flow is dominated by soil pore structure. Unlike previous studies that solely assessed the salt-holding effect of salt wastelands based on soil salt content, this study integrates cationic concentration ratios, which collectively influence soil pore structure. To explore the drivers of horizontal water flow from cultivated land to salinized wasteland, we chose typical fields as the experimental site in the Yichang Irrigation Subarea of the Hetao Irrigation District, China. Ten observation points were established to measure parameters including soil water and salt cation distribution, particle size composition, clay dispersion and pore size within the 0–100 cm soil depth. The results showed that soil texture in cultivated land became coarser as proximity to the salinized wasteland increased. The subsoil layer of cultivated land exhibited the highest degree of coarseness, approximately five times greater than the surface soil layer. In cultivated soil, the 0–70 cm layer had lower water content than salinized wasteland, while the 80–100 cm soil layer in cultivated soil exhibited higher water content. The water content difference between the upper and lower depths in cultivated land gradually decreased with decreasing elevation. Cultivated soils maintained low and consistent EC1:5 values below 10 dS m−1, whereas salinized wasteland soils (0–20 cm) peaked at > 40 dS m−1. At the cultivated land-wasteland interface, the 10–20 cm soil layer had elevated K+/Na+ levels. Cultivated soils showed higher K+/Na+ ratios and Ca2+ concentrations exceeding Na+ levels. The highest Mg2+/Na+ ratio was at 0–50 cm near the cultivated boundary. In the soil profile at the cultivated land-wasteland interface, maximum soil suspension turbidity occurred at around 50–100 cm soil depth. Given the diversity of local environment, the soil structure variability and corresponding driving mechanisms identified in this study may not universally apply, and it's crucial to explore region-specific mechanisms. [ABSTRACT FROM AUTHOR]

A comprehensive exploration into the efficiency thresholds of electrodialysis (ED) and conventional aerodynamic thermal (AT) methods for reconcentrating high-concentration solutions is absent in current discourse. To address the gap, this study undertakes explicit derivations and experimental investigations to discern the divergences in energy and exergy performances between these two methods. The experimental results reveal that the ED method exhibits 6.9 times higher energy output/input ratio than the AT method, yet its exergy efficiency is 2.1 times lower in the baseline scenario due to the oversight of spent solution restoration costs. Moreover, the exergy loss of each component is identified by comparing the maximum exergy efficiency with the experimental exergy efficiency. These results help pinpoint measures to address significant exergy loss in key components, thereby boosting system performance. For the ED method, innovation and advancement in membrane technology and materials should be prioritized due to the significant limitations imposed by imperfect membranes. While for the AT method, utilizing renewable energy sources like solar energy to power the heater can greatly enhance system efficiency, considering that exergy loss within the heater is the primary limiting factor. [ABSTRACT FROM AUTHOR]

The beneficial characteristics of polyoxometalate (POM) molecule-based flash memory cells provide interesting opportunities for scaling beyond the limitations of conventional flash cells. In this paper, we study the write, erase, and retention times of POM flash cells using a kinetic Monte Carlo method implemented in the multi-scale Nano-Electronic Simulation Software simulation framework. The POM flash structure is optimized by studying the tradeoffs between program/erase time and retention time. Based on the optimized POM flash structure, the POM molecular layer charging and discharging processes as well as the corresponding threshold voltage variation are analyzed. The distributions of write, erase, and retention times are simulated and analyzed when studying the POM flash dynamic charging and discharging characteristics. [ABSTRACT FROM AUTHOR]

It is demonstrated that gonadotropin-releasing hormone (GnRH) analogs can directly inhibit the proliferation of reproductive tissue cancer cells, but the poor pharmacokinetic properties still restrict their application in treating hormone-dependent diseases. Modifications in position 6 and 10 of natural GnRH can improve the metabolic stability. In order to study the effect of incorporation Cys6 substitution with C-terminal Pro9-NHEt modification and dimerization of linear peptides on metabolic stability and antiproliferative activity of GnRH analogs, two new GnRH analogs [l-Cys6, desGly10, Pro9-NHEt]-GnRH (1) and [d-Cys6, desGly10, Pro9-NHEt]-GnRH (2), and their corresponding dimer derivatives ([l-Cys6, desGly10, Pro9-NHEt]-GnRH)2 (3) and ([d-Cys6, desGly10, Pro9-NHEt]-GnRH)2 (4) were synthesized. Incubation of these analogs with human serum was carried out to evaluate their metabolic stability, and direct growth inhibitory effect of the two dimer derivatives 3 and 4 on MCF-7 human breast cancer cell line was examined by MTT assay. The metabolic stability of dimer derivatives 3 and 4 was remarkably improved in comparison with natural GnRH. The d-Cys6 substituted dimer derivative 4 exhibited higher inhibitory effect (29.6–39.7% growth reduction) on cell growth than its corresponding counterpart 3 (21.8–26.2% growth reduction) at concentration range of 50, 100 and 200 μΜ. The cell growth inhibition of leuprolide was 16.4–27.2% at the tested concentrations. The dimer derivative 4 was the most stable and active GnRH analog in this study and has the potential for future preclinical investigations as promising antitumor drug candidate. [ABSTRACT FROM AUTHOR]

Temperature profiles of sea ice have been recorded more than a few decades. However, few high-precision temperature sensors can complete the observation of temperature profile of sea ice, especially in extreme environments. At present, the most widely used sea ice observation instruments can reach an accuracy of sea ice temperature measurement of 0.1 °C. In this study, a multilayer sea ice temperature sensor is developed with temperature measurement accuracy from −0.0047 °C to 0.0059 °C. The sensor system composition, structure of the thermistor string, and work mode are analyzed. The performance of the sensor system is evaluated from −50 °C to 30 °C. The temperature dependence of the constant current source, the amplification circuit, and the analog-to-digital converter (ADC) circuit are comprehensive tested and quantified. A temperature correction algorithm is designed to correct any deviation in the sensor system. A sea-ice thickness discrimination algorithm is proposed in charge of determining the thickness of sea ice automatically. The sensor system was field tested in Wuliangsuhai, Yellow River on 31 January 2018 and the second reservoir of Fen River, Yellow River on 30 January 2018. The integral practicality of this sensor system is identified and examined. The multilayer sea ice temperature sensor will provide good temperature results of sea ice and maintain stable performance in the low ambient temperature. [ABSTRACT FROM AUTHOR]

• We establish a scheduling plan of canals and gates. • Combining canal hydrodynamic model with the scheduling model. • The model utilized the factor of water level rise in backwater area. • The model considers two cases of supply-decided and demand-decided. A complete water distribution scheme should include the scheduling of the check gates and turn out gates. This study aims to resolve the water distribution problem in irrigation districts based on channel hydrodynamic simulation and using the hydraulic factor of water level increase in backwater areas. The supply-decided water distribution and scheduling model(SD-WDSM), the demand-decided water distribution and scheduling model(dd -WDSM) were established respectively. The model was applied to the Bojili irrigation district to verify it's applicability. The results show that the SD-WDSM can adjust the length of the backwater area through the operation of the check gate, ensuring a large flow rate at the turn out gate. The dd -WDSM was established to group the water diversion canals by rotation irrigation, and the turn out gate in the same group could open and close simultaneously, which is convenient for the administrator to operate. The two models also ensure that the water is diverted as early as possible, and the operation numbers of the check gates and the turn out gates are less. The model obtains the complete scheduling scheme of the check gates and the turn out gates in the water distribution system. This model can improve agricultural water use efficiency and promote sustainable agricultural development. The proposed model is universal and can be applied to other irrigation districts. [ABSTRACT FROM AUTHOR]

• We establish three models based on water supply. • The model considers whether the water supply meets the demand. • The flow rate of primary canal is closer to the actual flow rate. • Ensure fairness as much as possible when water is insufficient. The optimization of canal water distribution is vital in irrigation areas because a reasonable distribution is required to improve the water distribution efficiency and maximize the benefits of water resources. In this paper, under the condition that the total volume and flow rate of water supply in the primary canal have been determined, the water supply is compared with crop water demand, and three optimal models of canal water distribution are established. In situation 1, the total volume of water supply is sufficient to meet the crop water demand during the growing period. In situation 2, the water supply is insufficient to meet crop water demand during their growth period; however, this problem is resolved by extending the water supply period. In situation 3, the water supply cannot meet the crop water demands during the growth period, even after adjusting the water supply period. Because the proposed water distribution optimization model is based on water supply conditions in irrigation areas, the irrigation area managers can easily develop their operation water distribution schemes. The model was validated using the Bojili irrigation area. Results showed that the model's calculated variation trend of the main-canal flow rate was similar to the actual flow rate, and irrigation area managers could meet the model requirements with a small adjustment in the actual flow rate. The model also considered canal leakage loss, timely water distribution, water distribution fairness, and other goals, potentially improving agricultural water efficiency and water distribution satisfaction as well as promoting sustainable agricultural development. The model presented here is universal and can be used in other irrigation areas. [ABSTRACT FROM AUTHOR]

From the perspective of energy providers, accurate short-term load forecasting plays a significant role in the energy generation plan, efficient energy distribution process and electricity price strategy optimisation. However, it is hard to achieve a satisfactory result because the historical data is irregular, non-smooth, non-linear and noisy. To handle these challenges, in this work, we introduce a novel model based on the Transformer network to provide an accurate day-ahead load forecasting service. Our model contains a similar day selection approach involving the LightGBM and k-means algorithms. Compared to the traditional RNN-based model, our proposed model can avoid falling into the local minimum and outperforming the global search. To evaluate the performance of our proposed model, we set up a series of simulation experiments based on the energy consumption data in Australia. The performance of our model has an average MAPE (mean absolute percentage error) of 1.13, where RNN is 4.18, and LSTM is 1.93. [ABSTRACT FROM AUTHOR]

Abstract: The dehumidifier and regenerator are key components in liquid desiccant air conditioning systems. Many researchers have developed mathematical models of the coupled heat and mass transfer processes in the dehumidifier or regenerator, and most of the models were solved numerically. Compared with numerical solutions, analytical solutions have more advantages in analyzing the parameters that affect the heat and mass transfer performance. This paper presents analytical solutions of the air and desiccant parameters inside the parallel flow, counter flow and cross flow dehumidifier/regenerator under some reasonable assumptions based on the available heat and mass transfer models. The analytical solutions of the air and desiccant parameters within the dehumidifier/regenerator show good agreement with the corresponding numerical results, and the analytical solutions of the enthalpy and moisture efficiencies agree well with experimental findings. The method developed here can be used in the optimal design of the dehumidifier or regenerator. [Copyright &y& Elsevier]

Accurate short-term small-area meteorological forecasts are essential to ensure the safety of operations and equipment operations in the Antarctic interior. This study proposes a deep learning-based multi-input neural network model to address this problem. The newly proposed model is predicted by combining a stacked autoencoder and a long- and short-term memory network. The self-stacking autoencoder maximises the features and removes redundancy from the target weather station's sensor data and extracts temporal features from the sensor data using a long- and short-term memory network. The proposed new model evaluates the prediction performance and generalisation capability at four observation sites at different East Antarctic latitudes (including the Antarctic maximum and the coastal region). The performance of five deep learning networks is compared through five evaluation metrics, and the optimal form of input combination is discussed. The results show that the prediction capability of the model outperforms the other models. It provides a new method for short-term meteorological prediction in a small inland Antarctic region. [ABSTRACT FROM AUTHOR]