Search Results (4,497)

Given the significant impact of concrete’s compressive strength on structural service life, the development of accurate and efficient prediction methods is critically important. A hybrid machine learning modeling method based on the Whale Optimization Algorithm (WOA)-optimized XGBoost algorithm is proposed. Using 1030 sets of concrete mix proportion data covering eight key parameters—cement, blast furnace slag, fly ash, water, superplasticizer, coarse aggregate, fine aggregate, and curing age—the predictive performance of four models (linear regression, random forest, XGBoost, and WOA-XGBoost) was systematically compared. The results demonstrate that the WOA-XGBoost model achieved the highest goodness of fit (R² = 0.9208, MSE = 4.5546), significantly outperforming the other models, and exhibited excellent generalization capability and robustness. Feature importance and SHAP analysis further revealed that curing age, cement content, and water content are the key variables affecting compressive strength, with blast furnace slag showing a significant marginal diminishing effect. This study provides a high-precision data-driven tool for optimizing mix proportions and predicting the strength of complex-component concrete, offering significant application value in promoting the resource utilization of industrial waste and advancing the development of green concrete. Full article

In order to alleviate the constraints of global warming and sustainable development, digitalization has made significant contributions to promoting agricultural carbon reduction through resources, technology, and platforms. Under this situation, China insists on developing agricultural scale management. However, what impact will scale management in agricultural digital emission reduction have on mechanisms and pathways? Based on three rounds of follow-up surveys conducted by the Digital Countryside Research Institute of Nanjing Agricultural University in Jiangsu Province from 2022 to 2024, in this study a total of 258 valid questionnaires on the rice and wheat industry were collected. Methods such as member checking and audit trail were employed to ensure data reliability and validity. Using econometric approaches including Tobit, mediation, and moderation models, this study quantified the Scale Management Level (SML), examined the mechanism pathways of digital emission reduction in a scaled environment, further demonstrated the impact of scale management on digital emission reduction, and verified the mediating and moderating effects of internal and external scale management. We found that: (1) In scale and carbon reduction, the SBM-DEA model calculates that the scale of agricultural land in Jiangsu showed an “inverted S” trend with SML and an “inverted W” trend with the overall agricultural green production efficiency (AGPE), and the highest agricultural green production efficiency is 0.814 in the moderate scale range of 20–36.667 hm². (2) In digitalization and carbon reduction, the Tobit regression model results indicate that Network Platform Empowerment (NPE) significantly promotes carbon reduction (p < 1%), but its squared terms exhibit an inverted U-shaped relationship with agricultural green production efficiency (p < 1%), and SML is significant at the 5% level. From a local regression perspective, the strength of SML’s impact on the three core variables is: NPE > DRE > DTE. (3) Adding scale in agricultural digital emission reduction, the intermediary mechanism results showed that the significant intensity (p < 5%) of the mediating role of Agricultural Mechanization Level (AML) is NPE > DTE > DRE, and that of the Employment of Labor (EOL) is DRE > NPE > DTE. (4) Adding scale in agricultural digital emission reduction, the regulatory effect results showed that the Organized Management Level (OML) and Social Service System (SSS) significantly positively regulate the inhibitory effect of DRE and DTE on AGPE. Finally, we suggest controlling the scale of land management reasonably and developing moderate agricultural scale management according to local conditions, enhancing the digital literacy and agricultural machinery training of scale entities while encouraging the improvement of organizational level and social service innovation, and reasonably reducing labor and mechanization inputs in order to standardize the digital emission reduction effect of agriculture under the background of scale. Full article

Hydrogen production from water electrolysis can not only reduce greenhouse gas emissions, but also has abundant raw materials, which is one of the ideal ways to produce hydrogen from new energy. The hydrogen production power supply is the core component of the new energy electrolytic water hydrogen production device, and its characteristics have a significant impact on the efficiency and purity of hydrogen production and the service life of the electrolytic cell. In essence, the DC/DC converter provides the large current required for hydrogen production. For the converter, its input still needs the support of a DC power supply. Given the maturity and technical characteristics of new energy power generation, integrating energy storage into offshore energy systems enables stable power supply. This configuration not only mitigates energy fluctuations from renewable sources but also further reduces electrolysis costs, providing a feasible pathway for large-scale commercialization of green hydrogen production. First, this paper performs a simulation analysis on the wind–solar hybrid energy storage power generation system to demonstrate that the wind–solar–storage system can provide stable power support. It places particular emphasis on the significance of hydrogen production power supply design—this focus stems primarily from the fact that electrolyzers impose specific requirements on high operating current levels and low current ripple, which exert a direct impact on the electrolyzer’s service life, hydrogen production efficiency, and operational safety. To suppress the current ripple induced by high switching frequency and high output current, traditional approaches typically involve increasing the output inductor. However, this method substantially increases the volume and weight of the device, reduces the rate of current change, and ultimately results in a degradation of the system’s dynamic response performance. To this end, this paper focuses on developing a virtual impedance control technology, aiming to reduce the ripple amplitude while avoiding an increase in the filter inductor. Owing to constraints in current experimental conditions, this research temporarily relies on simulation data. Specifically, a programmable power supply is employed to simulate the voltage output of the wind–solar–storage hybrid system, thereby bringing the simulation as close as possible to the actual operating conditions of the wind–solar–storage hydrogen production system. The experimental results demonstrate that the proposed method can effectively suppress the ripple amplitude, maintain high operating efficiency, and ultimately meet the expected research objectives. That makes it particularly suitable as a high-quality power supply for offshore hydrogen production systems that have strict requirements on volume and weight. Full article

Aluminum-based seawater activated batteries (Al-SWBs) are highly cost-effective energy storage systems, with aluminum exhibiting a theoretical specific capacity of 2.98 Ah/g, second only to lithium, making it a promising candidate for next-generation sustainable energy storage and conversion technologies. However, severe hydrogen evolution and self-corrosion side reactions hinder the practical application of Al-SWBs, leading to unsatisfactory utilization of aluminum anodes. This review systematically summarizes the fundamental principles and strategies for enhancing the utilization efficiency of aluminum anodes from the perspectives of influencing factors and improvement approaches. In terms of alloying element doping, attention should be paid not only to elements that enhance performance but also to the impact of harmful impurities. Microstructure control can be achieved through advanced preparation techniques and subsequent annealing processes. Furthermore, the addition of corrosion inhibitors to the electrolyte can form a protective layer on the electrode surface, effectively suppressing self-corrosion behavior. This review aims to provide valuable insights and guidance for the development of sustainable and high-performance Al-SWBs, contributing to the advancement of green energy technologies. Full article

The global transition to a low-carbon energy system requires innovative solutions that integrate renewable energy production with storage and utilization technologies. The growth in energy demand, combined with the intermittency of these sources, highlights the need for advanced management models capable of ensuring system stability and efficiency. This paper presents the development of an optimized energy management system integrating renewable sources, with a focus on green hydrogen production via electrolysis, storage, and use through a fuel cell. The system aims to promote energy autonomy and support the transition to a low-carbon economy by reducing dependence on the conventional electricity grid. The proposed model enables flexible hourly energy flow optimization, considering solar availability, local consumption, hydrogen storage capacity, and grid interactions. Formulated as a Mixed-Integer Linear Programming (MILP) model, it supports strategic decision-making regarding hydrogen production, storage, and utilization, as well as energy trading with the grid. Simulations using production and consumption profiles assessed the effects of hydrogen storage capacity and electricity price variations. Results confirm the effectiveness of the model in optimizing system performance under different operational scenarios. Full article

Urban parks play a crucial role in mitigating urban heat stress and maintaining ecological stability through their cold island effect (PCIE). However, studies examining how multidimensional urban morphology influences these effects, particularly from a diurnal perspective in island cities, remain limited. This study investigates 30 representative urban parks within a typical island city, exploring how two-dimensional and three-dimensional spatial morphological factors affect four key PCIE indicators: park cooling intensity (PCI), park cooling gradient (PCG), park cooling area (PCA) and park cooling efficiency (PCE) across different times of day and night. The results reveal that: (1) coastal zones exhibit significantly lower land surface temperature (LST) than inland zones, with peak LST occurring at 5:00 p.m.; (2) the four cold island indicators follow a diurnal pattern of 5:00 p.m. > 1:00 a.m. > 7:00 a.m.; (3) morphological construction factors—such as building density (BD) and built-up proportion (BP)—positively contribute to cooling effects at 7:00 a.m., while park perimeter (PP) enhances cooling performance at both 5:00 p.m. and 1:00 a.m. Additionally, vegetation characteristics surrounding parks, including the normalized difference vegetation index (NDVI) and green space proportion (GP), influence daytime cooling in directions opposite to those of the aforementioned construction-related factors. These findings offer valuable insights into the temporal dynamics and spatial determinants of urban park cooling in island cities, providing a scientific basis for scientifically informed park planning and contributing to healthier and more sustainable urban development. Full article

Food legumes play a pivotal role in China’s food security, nutritional health, and green development strategies due to their unique advantages. This paper presents an empirical study on the economic evaluation of scientific research on pest and disease control for food legumes. Using panel data from 31 Chinese provinces from 2008 to 2023, we employ a Double Machine Learning (DML) approach to identify the impact of investment in plant protection research on food legume outputs. The results indicate a steady increase in China’s investment in this field, with an average annual growth rate of 5.19% from 2008 to 2023, and the total investment in 2023 was 2.14 times that of 2008. Investment in plant protection research effectively mitigates output losses and leads to significant production increases. Specifically, a 1% increase in research investment corresponds to a 0.2% increase in food legume output. This effect remains robust across various algorithms, time windows, and control variable settings. Based on these findings, we recommend: (1) increasing financial support and talent acquisition for research on food legume pests and diseases to enhance the stability and sustainability of research investment; (2) strengthening cooperation mechanisms between research institutions and enterprises to leverage their respective strengths and promote the commercialization of research outcomes and regional variety extension; (3) establishing a diversified research investment system that explores a co-construction model guided by the government, involving enterprises, and utilizing public–private partnerships to reconcile the conflict between long research cycles and market demands; (4) fostering a dual-track linkage between regional technological innovation and enterprise product commercialization to improve the efficiency of technology transfer and application; and (5) strengthening R&D in cutting-edge fields like Artificial Intelligence to improve the efficiency and precision of pest and disease control. Full article

Under the “dual carbon” strategy, achieving synergy between pollution reduction and carbon mitigation is crucial for the sustainable development of coastal cities. However, existing studies frequently emphasize single-carbon reduction measures whilst neglecting to acknowledge the cross-sectoral synergistic effects. This study takes the Haishu District of Ningbo in Zhejiang Province as a case study and quantitatively assesses the effectiveness of synergistic governance strategies across four key pathways: photovoltaic power generation, carbon sequestration by green land, new energy transportation, and waste incineration for power generation. The results demonstrate that multi-sectoral coordinated management significantly enhances overall emission reduction efficiency, with the photovoltaic and waste-to-energy pathways showing the highest carbon reduction potential. This study establishes a multi-pathway framework for evaluating the synergistic effects of pollution and carbon reduction. It also provides scientific support for decision-making regarding the transition to a low-carbon economy in coastal cities, and proposes a replicable evaluation methodology that can be used to implement dual carbon strategies in other coastal regions. Full article

The comprehensive renovation of existing buildings has become imperative and is recognized as a central priority within the European Union’s agenda (European Green Deal). The objectives of this initiative include reducing energy consumption, mitigating environmental pollution, and achieving long-term decarbonization targets. This research addresses the case of load-bearing masonry buildings constructed in the post-World War II period, characterized by specific geometric and volumetric features. Current regulations on seismic design and thermal protection reveal significant deficiencies in both the structural safety and the energy performance of these buildings. Recent seismic events and the increasing demand for electricity further highlight the urgency of integrated retrofitting measures that simultaneously enhance structural resistance and improve thermal protection. This research aims to develop an integrated retrofitting approach that simultaneously improves seismic resistance and energy efficiency. A review of strengthening techniques and thermal upgrades was carried out, followed by a critical assessment of their applicability. The proposed intervention combines two comparable seismic reinforcement schemes with thermal improvements, implemented through a one-sided reinforced cement mortar overlay coupled with external thermal insulation materials. Analyses demonstrate that the retrofit increases the structural resistance to a_gR = 0.10 g and upgrades the building envelope to current energy efficiency requirements. The results confirm that the method is both effective and feasible, offering a replicable solution for similar residential masonry buildings. This study concludes that integrated retrofitting can extend building service life, enhance occupant safety and comfort, and provide a practical framework for large-scale application in sustainable renovation practices, which is especially significant for Serbia and other Balkan countries, considering that the analyzed case study buildings are characteristic representatives for these regions. Full article

Sugar beet (Beta vulgaris L.) is very sensitive to fluctuations in micronutrient availability, and either an excess or a shortage of boron (B) may reduce the plant’s development and its ability to withstand stress. B is essential for photosynthesis and cell wall integrity, but the physiological requirements for an optimal supply during early development remain unclear. The photosynthetic efficiency and oxidative stress reactions of sugar beet seedlings were tested under five different B concentrations: 0, 50, 500, 1000, and 2000 µM H₃BO₃. Integrating non-invasive methods like SPAD, delayed fluorescence (DF), and maximum quantum efficiency of PSII (Fv/Fm) with red–green–blue (RGB) imaging enabled the detailed processing of both the initial and decay phases of DF. According to the results, SPAD and Fv/Fm were not sensitive indicators of early B stress; however, DF decay slopes and red–green–blue pixel distribution distinguished between optimum (500 µM), inadequate (0 µM), and hazardous (2000 µM) treatments. Moreover, lipid oxidation-related biochemical analyses were used to evaluate the ferric reducing antioxidant capacity (FRAP) and malondialdehyde (MDA) concentration. At the extremes of insufficiency and toxicity, MDA levels demonstrated enhanced lipid peroxidation, while FRAP increased with B concentration. The outcome of the research revealed optimum (500 µM) and toxicity-inducing (2000 µM) concentrations at early stages of sugar beet development. The study highlights that the combined use of DF kinetics and RGB analysis provides valuable, non-invasive markers for the early identification of B-stress, which is also confirmed by biochemical indicators, thereby promoting more efficient micronutrient management in sugar beet cultivation. Full article

Chemical fertilizers are commonly used to supply phosphorus and other nutrients to crops, but due to high affinity of soils for P fixation, over-application of P fertilizer is common, which may result in groundwater and surface water pollution. To increase P use efficiency, different strategies, including different fertilizer formulations and types, have been developed. Two struvite-based fertilizers, Crystal Green^® (CG) and Crystal Green Pearl^® (CGP), are touted as environmentally safe, because they are insoluble in water but soluble in organic acids exuded from crop roots. The objective of this study was to assess fate and transport of P from diammonium phosphate (DAP), CG, and CGP through two loam soils with a significant difference in their initial P content. Two loamy soils, one collected from an experimental field receiving fertilizer continuously since 1985 and one from an adjacent area receiving no fertilizer, and a pure sand control were packed in 5 cm diameter and 5 cm long columns. Several grains equivalent to approximately 80 mg P from each fertilizer were imbedded at the bottom of the column. Distilled water was passed through the soil columns from the bottom at a relatively constant rate, and the outflow was collected every two hours using a fraction collector. Outflow samples from each treatment combination were analyzed for P by the colorimetric method, and the amount of P retained by the soils along the column at the end of the water application was determined by the nitric acid digestion method. Approximately 91% of P in DAP, 34% in CG, and only 3.8% in CGP was transported through the sand column. In contrast, the amounts of P transported were approximately 42.2% for DAP, 6.4% for CG, and 0.4% for CGP through the high-P soil and 22.4% for DAP, 0.6% for CG, and almost zero for CGP through the low-P soil. Overall, the results show a high solubility and transport for DAP, very low transport for CGP, and somewhat low to medium transport for CG fertilizers. In addition, the results show that even the high-P soil that has received fertilizer for about 40 years has the capacity to fix significant amounts of P. Full article

The diverse phytochemical profiles of host plants can significantly influence their interactions with herbivores and natural enemies. This study investigated the ‘bottom-up’ effects of several bell pepper and eggplant cultivars on the development, reproduction, and survival of the green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), and its predators, Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae) and Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae). We analyzed the leaves of each cultivar for levels of total flavonoids, phenols, anthocyanins, and key defensive enzymes. The eggplant cultivar ‘Longo’ exhibited the highest concentration of secondary metabolites. Aphid populations reared on this cultivar’s leaves showed a slower growth rate compared to those on other cultivars. Conversely, predators fed on these aphids demonstrated higher rates of population growth and produced more offspring. Accordingly, the intrinsic rate of natural increase (r) was lower for aphids feeding on ‘Longo’, but significantly higher for both A. aphidimyza and C. carnea when fed those aphids. These results demonstrate that elevated secondary metabolites on ‘Longo’ suppress the performance of M. persicae while enhancing predator efficiency, thereby providing a phytochemical-based approach that can serve as an effective component of integrated pest management (IPM) programs. Full article

The ongoing digitalization of energy infrastructure is a crucial enabler for improving efficiency, reliability, and sustainability in gas distribution networks, especially in the context of decarbonization and the integration of alternative energy carriers (e.g., renewable gases including biogas, green hydrogen). This study presents the development and application of a Digital Twin framework for a real-world gas distribution network developed using open-source tools. The proposed methodology covers the entire digital lifecycle: from data acquisition through smart meters and GIS mapping, to 3D modelling and simulation using tools such as QGIS, FreeCAD, and GasNetSim. Consumption data are collected, processed, and harmonized via Python-based workflows, hourly simulations of network operation, including pressure, flow rate, and gas quality indicators like the Wobbe Index. Results demonstrate the effectiveness of the Digital Twin in accurately replicating real network behavior and supporting scenario analyses for the introduction of greener energy vectors such as hydrogen or biomethane. The case study highlights the flexibility and transparency of the workflow, as well as the critical importance of data quality and availability. The framework provides a robust basis for advanced network management, optimization, and planning, offering practical tools to support the energy transition in the gas sector. Full article

Green transformation is becoming key for corporate sustainability in the context of global carbon neutrality goals and China’s “dual carbon” strategy (peak carbon emissions and carbon neutrality). Digital transformation, particularly supply chain digitization, plays a significant role in green transformation. Corporations could improve environmental performance through appropriate resource allocation. Much academic and practical attention is drawn to this area to motivate corporate green transformation. This research proposes to explore the incentive effect of supply chain digitization on corporate green transformation and analyze the mediation mechanism of carbon information disclosure and the regulatory effect of external investor supervision. The study samples Chinese A-share listed firms between 2012 and 2024, constructs a moderated mediation effect model, and arrives at the following conclusions: (1) The digitization of the supply chain significantly stimulates the green transformation of public firms, indicating that digital technology promotes the green development of enterprises through optimizing supply chain management and improving environmental governance efficiency; (2) Carbon information disclosure plays a partial intermediary role between supply chain digitization and corporate green transformation, that is, supply chain digitization enhances the quality of carbon information disclosure and further strengthens the willingness and ability of enterprises to undergo green transformation; (3) The positive regulatory effect of external supervision on carbon information disclosure by investors indicates that external regulatory pressure can enhance the transmission effect of carbon information disclosure on corporate green transformation; (4) Heterogeneity analysis shows that supply chain digitization has a more significant incentive effect on green transformation for manufacturing firms, state-owned enterprises, and high-polluting enterprises, indicating that industry attributes, property rights, and environmental regulation intensity affect the effectiveness of digital green transformation. Full article

The forest food industry, as a typical low-carbon green ecological industry, holds strategic significance in addressing global food security challenges. This review takes forest protein resources as an example to analyze the current development status, opportunities, and challenges from a global industrial perspective. Research indicates that forests, as a vital food treasure for humanity, can provide diverse protein sources such as insects, plants, microorganisms, and bio-manufactured proteins. Currently, numerous technological innovations and market practices have emerged in fields such as insect protein (e.g., there are over 3000 edible insect species globally, with a market size of approximately USD 3.2 billion in 2023, projected to reach USD 7.6 billion by 2028), plant-based alternative protein (e.g., plant-based chicken nuggets by Impossible Foods in the United States), microbial fermentation protein (e.g., the production capacity of Solar Foods’ production base in Finland is 160 tons per year), and cell-cultured meat (e.g., cell-cultured chicken is sold in Singapore), demonstrating significant potential in alleviating food supply pressures and reducing environmental burdens. However, industrial development still faces practical challenges including insufficient resource exploration, incomplete nutritional and safety evaluation systems, low consumer acceptance, high costs of core technologies (e.g., the first cell-cultured meat burger in 2013 cost over 1 million USD/lb, and current costs need to be reduced to 17–65 USD/kg to achieve market competitiveness), and imperfect regulatory mechanisms (e.g., varying national standards lead to high compliance costs for enterprises). In the future, it is necessary to achieve efficient development and sustainable utilization of forest protein resources by strengthening resource exploration, clarifying the basis of nutrients, promoting multi-technology integration and innovation, and establishing a sound market access system, thereby providing solutions for global food security and high-quality development of the food industry. Full article