Search Results (1,251)

Ploughing constitutes a fundamental tillage practice for enhancing soil fertility as well as water and fertilizer utilization efficiency. The uniformity of tillage depth directly determines seedling emergence consistency and final crop yield. Conventional indirect tillage depth detection approaches based solely on the rotation angle of the tractor lift arm are susceptible to disturbances induced by uneven terrain and dynamic attitude fluctuations of the tractor-implement system. To compensate for disturbances induced by tractor pitch angle variations, existing pitch compensation models adopt cascaded output compensation to calculate tillage depth. Nevertheless, these models need recalibration after each modification to the three-point hitch linkage length and are incapable of simultaneously compensating for pitch variations in the tractor and attached implement. To reduce the sensitivity of the tillage depth model to structural changes in the three-point hitch, this work constructs a mapping between hitch structural geometric deviations and vertical projection offsets of key linkages via tractor–plough integrated distributed attitude sensing. In this paper, a distributed tillage depth model is developed, which takes the distributed attitude of the whole working unit and the pitch of the lower-link measured by a rotation angle sensor as independent input variables. Field validation was performed with a mounted moldboard plough, with ultrasonic ranging sensor tillage depth readings serving as the reference benchmark to assess the reliability and precision of the proposed distributed model. Experimental results show that compared with the pitch angle cascaded tillage depth model, the average root mean square error of the proposed method is reduced from 22.5 mm to 12.5 mm on bumpy fields and from 11.3 mm to 8.7 mm on flat fields. The distributed model can significantly improve the measurement accuracy and anti-interference capability of tillage depth detection on uneven farmland, and it is applicable to adaptive measurement and control of tillage depth in complex ploughing scenarios. Full article

Data of experimental, comparative, and allometric studies was examined in relation to the wider oxygen transport cascade, including branchial ventilation, diffusion across the water–blood barrier, blood oxygen transport, muscle capillarization, and mitochondrial content. Experimental reductions in functional gill area are associated with lower maximal oxygen consumption and reduced critical swimming speed, whereas reversible gill remodelling may increase exposed lamellar surface under hypoxia or increased oxygen demand. Comparative evidence indicates that gill area accounts for a measurable, but incomplete, component of variation in metabolic rate and hypoxia tolerance. A descriptive comparison of ten published paired gill surface area (GSA) and standard metabolic rate (SMR) datasets did not reveal a consistently negative difference between gill surface area and standard metabolic demand across the species and experimental conditions examined. This comparison addresses maintenance metabolism but does not test oxygen-supply constraints during routine or maximal activity. The broader evidence reviewed includes large salmonids with cardiovascular compensation, cyprinids with reversible gill remodelling, haemoglobinless icefishes, and active pelagic taxa with high cardiorespiratory and locomotor investment. Collectively, these examples show that the functional significance of gill area depends on interacting branchial, cardiovascular, haematological, tissue-level, and ecological traits. Full article

Recycled brick aggregate (RBA) and old mortar (OM) account for a large proportion of construction and demolition waste. To date, few systematic studies have addressed how their coupling interaction governs the performance of recycled concrete (RC). In this study, a two-factor experimental design was carried out, where RBA content (0–15%) and OM content (0–15%) were set as independent variables. The physical properties of recycled aggregates (RAs) and mechanical behaviors of RC were measured, and the underlying mechanisms were elaborated from both macroscopic and microscopic perspectives. Experimental results reveal that increasing RBA and OM contents raise the water absorption and crushing value of RA while reducing their apparent density. OM exerts a more substantial impact on water absorption and apparent density, whereas RBA predominantly controls the fluctuation of crushing value. When RBA dosage rises from 0% to 15%, the maximum reductions in compressive strength and flexural strength reach 20.7% and 23.4%, respectively. When OM dosage increases from 5% to 15%, the corresponding strength reductions are 24.8% and 20.3%. Scanning electron microscopy (SEM) characterizations prove that internal pores and microcracks within RBA, along with loose zones at the interface between OM and fresh mortar, act as vulnerable paths for crack initiation and propagation, which deteriorates the bulk macroscopic mechanical properties. Range analysis and analysis of variance confirm that RBA serves as the dominant influential factor. The contribution proportions of RBA to compressive strength and flexural strength are 68.3% and 72.5%, which exceed those of OM (31.7% and 27.5%). The combined action of RBA and OM produces an evident negative superposition effect, with no detectable performance compensation effect observed. This research lays a solid foundation for optimizing the mixing proportion of RA derived from construction waste and promoting the engineering application of RC. Full article

Arbuscular mycorrhizal fungi (AMF) are widely reported to restore photosynthetic efficiency under phosphorus deficiency. Whether this holds under combined phosphorus-and-zinc deficiency in early-stage maize (Zea mays), and how AMF modify the relationship between photosynthetic efficiency and growth rate, remains unresolved. Maize variety SUWAN 5819 was grown under five nutrient treatments (+Zn+P, −Zn−P, +Zn−P, −Zn+P, deionized water) with and without AMF in a sand culture under a randomized complete block split-plot design with six replications. Chlorophyll fluorescence, stomatal conductance, and growth-analysis variables were measured. Lindeman–Merenda–Gold (LMG) variance partitioning and piecewise structural equation modelling (SEM) decomposed the relative growth rate (RGR) into net assimilation rate (NAR) and leaf area ratio (LAR) components. AMF reduced the quantum efficiency of photosystem II (ΦPSII) by 29.6–30.8% in phosphorus-deficient treatments. Despite this, AMF had no significant effect on NAR, LAR, or RGR across any treatment. NAR contributed 62.9–99.2% of explained RGR variance across all treatment combinations, consistently exceeding LAR. Under combined −Zn−P deficiency, stomatal conductance was significantly elevated despite reduced ΦPSII and ETR. The piecewise SEM showed that AMF caused a 1.7 times increase in the negative effect of −Zn−P on ΦPSII. This study shows that phosphorus is the main determinant of the quantum efficiency of photosystem II whilst AMF under phosphorus deficiency reduce photochemical efficiency without a compensating growth benefit in early vegetative maize. Full article

In the context of water scarcity and tightening environmental requirements, improving the energy efficiency of biological wastewater treatment processes has become particularly important. The aeration tank is one of the most energy-intensive and dynamically complex units, strongly affected by the variability in influent flow and composition. Conventional PID controllers do not provide predictive disturbance compensation and often result in excessive aeration and increased energy consumption. The study proposes an intelligent control approach based on a digital twin, neural network-based influent flow forecasting, and model predictive control (MPC). The digital twin represents a dynamic model of the biological process incorporating key state variables, including substrate, activated sludge, and dissolved oxygen concentrations. The LSTM neural network model is employed to predict the hydraulic load based on historical plant operation data, as well as to compensate for residual nonlinear dynamics that are not represented by the linearized MPC model. The predicted influent flow values are incorporated into the MPC framework as measured disturbances, enabling the generation of anticipatory control actions for the aeration system. The adequacy of the digital twin was validated using operational data from the wastewater treatment facilities of Semey city and was characterized by RMSE = 0.14 mg/L, MAE = 0.09 mg/L, R² = 0.94, and MAPE = 6.3%. The simulation results demonstrated that, compared with the fuzzy PID controller, the application of MPC reduced the RMSE by 57.1%, decreased the overshoot from 24% to 8%, reduced the integral absolute error (IAE) by 60.9%, and lowered the energy consumption of the aeration system by 21.1%, while maintaining the dissolved oxygen concentration within the permissible operating range. The proposed Advisory MPC architecture is compatible with existing PLC–SCADA systems and can serve as a basis for the gradual digital modernization of wastewater treatment facilities without modifying the existing automation loops. Full article

Bismuth hexacyanoferrate (BiHCF), a Prussian blue analogue containing redox-active Fe–CN–Bi coordination motifs, was investigated as a model electrode for cathodic processes in chloride-rich saline and hypersaline electrolytes. Rather than evaluating BiHCF solely as a hydrogen evolution catalyst, this work focuses on the coupled electrochemical and interfacial processes that govern its response in NaCl solutions and natural brines from seawater, reverse osmosis (RO) reject, and high-altitude brine environments. Structural characterization by SEM–EDS, XRD and FTIR confirmed the formation of crystalline BiHCF with rod-like micrometric morphology and preserved cyanide coordination. Linear sweep voltammetry under controlled hydrodynamic conditions revealed a progressive cathodic displacement of the mixed potential with increasing NaCl concentration, together with a marked suppression of oxygen reduction kinetics at high chloride activity. Mixed-potential analysis showed that HER kinetics remain comparatively less sensitive to salinity than ORR, whereas the anodic contribution associated with BiHCF oxidation becomes strongly affected by chloride-induced surface transformation. Post-electrochemical characterization indicates the formation of a BiOCl-rich surface layer when the BiHCF is in contact with a hypersaline electrolyte during the cathodic subprocess (close to 0 mV_SHE), which accounts for the transition from active mixed-control behaviour to a passivated interfacial regime. Density functional theory calculations suggest that elementary water activation and hydrogen-forming steps at Bi sites are intrinsically feasible, implying that the experimentally observed overpotentials originate primarily from transport, interfacial resistance and chloride-driven passivation rather than from an unfavourable molecular reaction pathway. These findings provide a mechanistic framework for understanding Bi-based Prussian blue analogue electrodes in non-purified saline electrochemical systems and highlight the dual role of chloride as both a charge-compensating electrolyte species and a passivating reactant. Full article

This study investigated the effects of drought during reproductive and boll development stages under elevated CO₂ conditions. A pot experiment was conducted in the Soil–Plant–Atmospheric-Research (SPAR) facility using the upland cotton cultivar DP 1646 B2XF grown under control (well-watered; 0.12 m³ H₂O m⁻³ soil) and drought (0.09 m³ H₂O m⁻³ soil) conditions at ambient (425 ppm; aCO₂) and enriched (725 ppm; eCO₂) CO₂ concentrations. Under drought stress, photosynthesis and stomatal conductance decreased by 35% and 63%, respectively, under aCO₂, whereas reductions were less pronounced under eCO₂ (20% and 36%). Under drought and aCO₂, intrinsic and instantaneous water-use efficiency increased by 74% and 45%, respectively, compared to control. Biomass partitioning shifted under drought, with increased allocation to shoots (55%) and roots (9%) and reduced allocation to reproductive organs (36%), compared to control conditions. Flowers produced under drought had 21% fewer ovules under both CO₂ environments, while pollen production remained unaffected. Seed cotton and lint weights were reduced by 19% and 15% under drought, respectively. However, plants grown under eCO₂ attained seed cotton and lint weights that were 20% higher than those grown under aCO₂, under both control and drought conditions. Drought significantly affected fiber quality, increasing micronaire by 26% and reducing fiber length by 4%, regardless of CO₂ level. eCO₂-driven alleviation primarily acts through carbon assimilation and yield compensation, with limited capacity to regulate developmental programming and quality formation. Full article

Groundwater is an essential natural resource for human societies and ecosystems. Traditional groundwater monitoring relies on in situ wells, which are susceptible to discontinuity, influencing water resource management. To overcome this deficiency, this study proposes a remote sensing-based groundwater level (GWL) monitoring system that uses machine learning (ML) algorithms and remotely sensed hydrological parameters to reconstruct well-specific GWL time series. Four machine learning algorithms, including K-Nearest Neighbor (KNN), Random Forest (RF), Extreme Gradient Boosting (XGBoost), and a weight-mean Ensemble strategy, were adopted to construct the models at each well individually for monitoring GWL. Specifically, the GWL data for ~770 wells across the conterminous United States (CONUS) were modeled using remotely sensed precipitation (P), evapotranspiration (ET), terrestrial water storage anomaly (TWSA), and soil moisture (SM) datasets during the period from 2004 to 2019. Afterwards, the performances of models were evaluated during an independent period from 2020 to 2023. The results show that the Ensemble model outperforms the individual baseline models evaluated in this study (i.e., KNN, RF, and XGBoost), achieving a mean coefficient of determination (R²) of 0.81, root mean square error (RMSE) of 0.34 m, normalized RMSE (NRMSE) of 11.8%, and Nash–Sutcliffe efficiency (NSE) of 0.78. The results demonstrate that the proposed system can effectively reconstruct GWL dynamics for most wells. This can be a compensation for missing records for hydrologically significant wells, which are those with historical groundwater observations. Full article

Compound spring floods in cold-continental and semi-arid interiors arise from interacting snowmelt, rain-on-snow events, intense precipitation, and frozen or saturated soils, yet these mechanisms remain poorly synthesized for Central Asia. This review develops a process-oriented framework linking preconditioning, triggers, propagation/amplification, impacts, and recovery outcomes. The synthesis shows that the most destructive spring floods occur when substantial antecedent snow storage and restricted infiltration coincide with rapid warming and rainfall, producing efficient runoff generation and widespread impacts. Evidence from Kazakhstan and comparable continental regions indicates that mechanistic understanding is relatively robust, but standardized event-level reporting of snow-water equivalent, soil wetness, precipitation phase, routing constraints, and recovery indicators remains uneven. To support post-disaster comparison, we introduce and demonstrate a Recovery Effectiveness Index (REI) combining housing resettlement, compensation, infrastructure restoration, and equity of assistance. A proof-of-concept application to the 2024 Kazakhstan floods produced a 21 June 2024 snapshot REI of 0.607–0.757 and an end-year REI of 0.850–1.000, depending on the treatment of the equity component. The framework supports compound-driver monitoring, early warning, recovery benchmarking, and more harmonized flood-risk assessment in data-sparse continental regions. Full article

The Western Route of the South-to-North Water Diversion Project is a significant water conservancy project that has undergone years of discussion. This study employed the emergy method to evaluate the ecosystem service value (ESV) of its water source areas from 2002 to 2022, analyzing spatial heterogeneity, and evaluating trade-offs and synergies among ecosystem services. The high-emergy areas for water supply are concentrated in the lower reaches of the basin, Liangshan Prefecture had the highest emergy, increasing from 1.14 × 10²¹ sej to 1.65 × 10²¹ sej over the 20 years. The climate regulation emergy values of Ganzi Prefecture, Aba Prefecture, and Liangshan Prefecture were relatively stable. The biodiversity remained relatively stable with small fluctuations, but exhibited significant spatial heterogeneity. Liangshan Prefecture and Lijiang City had the highest biodiversity emergy values, at 1.21 × 10²¹ sej and 2.05 × 10²¹ sej respectively, corresponding to as many as 7661 and 13,000 species, respectively. Among the service types, provisioning services and supporting services account for a relatively high proportion. The water supply increased by 6.13%, while the biodiversity decreased by 5.42%. The relationship showed particularly intense conflict of −0.965. Analyzing the spatiotemporal evolution of ESV in water source areas is of great significance for rationally guiding the phased and seasonal allocation of water transfer volumes, implementing ecological compensation, and assessing the impacts of water conservancy projects on the ecological environment. Full article

To address the challenges in multi-scale defect detection on railway track surfaces—such as the high likelihood of missing tiny defects, weak anti-interference capability in complex environments, and poor scale adaptability—this paper proposes a WTConv-YOLOv11 detection model based on wavelet convolution and scale dynamic loss, specifically tailored for embedded scenarios in intelligent inspection robots. By embedding a wavelet convolution module, the model leverages multi-frequency decomposition characteristics to enhance multi-scale defect feature extraction, effectively compensating for the shortcomings of traditional convolution in detail extraction and limited receptive fields. Meanwhile, a Scale Dynamic Loss (SD Loss) function is introduced to adaptively adjust regression weights according to defect scales, significantly reducing multi-scale target localization deviations and Intersection over Union (IoU) fluctuations. Experiments conducted on a real-world railway dataset comprising 2396 track defect images demonstrate that the proposed model achieves mean Average Precision (mAP)@0.5 of 82.56%, which is 12.16 percentage points higher than the original YOLOv11. With an inference speed of 99 FPS, the model balances high accuracy with real-time performance. Real-world testing further verifies the model’s robustness under strong light, shadows, and water stains, providing effective technical support for intelligent unmanned railway inspection. Full article

The alternative fulfillment mechanism for ecological and environmental damage liability represents a pivotal institutional innovation. Its principal function is to enable liable parties—under exceptional circumstances—to flexibly fulfill their ecological and environmental damage liability. This study adopts an empirical research method to systematically investigate the judicial application of the alternative performance mechanism. Findings reveal that under the guidance of the restorative justice concept, courts increasingly subsume diverse alternative performance modalities under the category of “alternative restoration”, leading to the gradual distortion of the alternative restoration centered on the concept of “equivalent restoration” into a “universal solution” for ecological damage cases. This practical tendency significantly weakens the actual effectiveness of ecological restoration. The purpose of this study is to establish a dual mechanism of alternative fulfillment—distinguishing between alternative restoration and alternative compensation—based on ecological principles and within the framework of the dual responsibilities of “restoration—compensation” for ecological environmental damage. The effectiveness of the dual mechanism is quantitatively evaluated using the AHP-fuzzy comprehensive evaluation. The evaluation results show that, after distinguishing between the two types of alternative responsibilities, the comprehensive evaluation scores for ecological damage remedy in cases of ecological destruction, water pollution, and soil pollution increased from 5.155 to 8.935, from 6.406 to 9.116, and from 6.137 to 9.108, respectively, effectively correcting the functional deviation of the current single-dimensional remedy model. This study clarifies the independent application criteria of alternative restoration and alternative compensation, and provides targeted optimization paths for the judicial application of ecological damage remedy. Full article

Underwater object detection is a fundamental task in underwater sensing and is generally approached using either optical or sonar sensors. Although optical imaging provides rich semantic information, it is highly susceptible to water turbidity and illumination variations. By contrast, sonar imaging can effectively overcome visibility limitations, yet it suffers from severe speckle noise and blurred object contours. Moreover, resource-limited platforms impose strict demands on model lightweightness and real-time performance. To this end, this paper proposes a novel cross-modal heterogeneous distillation method (CMHD) to balance detection accuracy and computational complexity. CMHD performs cross-modal knowledge transfer by leveraging the rich semantics of RGB images to enhance sonar feature representation, compensating for the information deficiency of the sonar modality. Meanwhile, a heterogeneous distillation scheme compresses the detection capability of a high-capacity teacher YOLOX-M into a lightweight student YOLOX-S-Ghost, enabling strong feature extraction under a highly compact model. To mitigate the modality gap and geometric inconsistency between RGB and sonar modalities, we design a branch-aware heterogeneous distillation strategy. To improve detection accuracy and reduce model parameters, the student network incorporates Coordinate Attention (CA) in its backbone and adopts a lightweight neck design. Experiments on the UXO^† dataset demonstrate that CMHD achieves 79.6% mAP and 82.6% mAR, significantly outperforming the compared representative methods and serving as an accurate, efficient, and lightweight solution for underwater sonar object detection. Full article

UV-based water treatment technologies are suitable for removing persistent organic micropollutants and can be used as a quaternary treatment in the production of drinking water. The most commonly used light source is a low-pressure mercury vapor lamp (LPMV) that emits at 254 nm. KrCl excimer lamps emitting at 222 nm are a potential mercury-free light source for ultraviolet (UV)-based advanced oxidation processes. In addition, 222 nm UV light may be more effective in photolysis of oxidants and radical generation than 254 nm. Experiments were conducted in both ultrapure water and biologically treated domestic wastewater, using LPMV and KrCl lamps, with two radical promoters (H₂O₂ and peroxydisulfate (PDS)) to transform and eliminate the trimetoprim antibiotic. At the same electrical power, the UV photon flux of the LPMV exceeds that of the KrCl lamp by an order of magnitude. However, the molar absorbance of PDS and H₂O₂ at 222 nm was significantly higher than that measured at 254 nm, thereby compensating for the low photon flux. Although competition between trimethoprim and matrix components for 222 nm UV photons may significantly reduce efficiency, the 222 nm excimer lamp was found to be a viable alternative to the 254 nm LPM, given its advantages and disadvantages. Full article

The selective gas-phase oxidation of γ-picoline (γ-P) to isonicotinic acid (INA)—a key precursor for the anti-tuberculosis drug isoniazid—was investigated over a V–Mn oxide catalyst as a solvent-free, waste-minimizing alternative to conventional liquid-phase synthesis routes. XRD and Raman spectroscopy confirmed the formation of a stable manganese vanadate crystalline phase with a high concentration of terminal vanadyl groups (V=O), providing well-defined redox-active sites. Water vapour proved essential for sustainable process performance: at an optimal H₂O/substrate molar ratio of 98, γ-picoline conversion reached 94.8% with INA selectivity of 86.5%, eliminating the need for hazardous solvents or additives. NH₃-TPD and kinetic analysis revealed that water vapour acts as a competitive adsorbent at vanadium Lewis acid sites, accelerating target product desorption and suppressing deep oxidation to COx—directly reducing carbon waste. Long-term stability was assessed over 96 h of continuous operation: the 23.4% decline in specific surface area correlated with an equivalent reduction in total acidity, while pore diameter expansion from 2.07 to 3.25 nm mitigated diffusion limitations, partially compensating for deactivation. These findings establish the V–Mn oxide system as a promising green catalytic platform for upgrading petrochemical fractions into high-value pharmaceutical intermediates with reduced environmental impact. Full article