Search Results (2,508)

In deep-buried tunnels, the loads acting on supporting structures continuously increase due to the rheological behavior of surrounding rock, while the performance of the secondary lining gradually degrades under environmental effects. These delayed features have significant implications for tunnel safety but are rarely incorporated into the reliability evaluation of tunnels. In this study, the surrounding rock is modeled using the Burgers model, and an analytical solution is developed by incorporating the degradation and damage of the secondary lining. Parametric analysis is conducted to identify the key factors governing tunnel response. Subsequently, limit state functions are established, and a time-dependent system reliability analysis is performed. Results indicate that tunnel response and reliability are highly sensitive to rheological parameters. Among the rheological parameters, the elastic shear modulus of the Maxwell elements G_e has the most pronounced influence on deformation, whereas the elastic shear modulus of the Kelvin elements G_k governs the stress response of the secondary lining. The time-dependent failure probability increases rapidly in the early stage and gradually stabilizes thereafter. Insufficient initial support strength is identified as the dominant failure mode of system failure. Furthermore, G_e and G_k are the key parameters affecting tunnel reliability, and increasing G_k improves the reliability index by more than 1500%. Meanwhile, the variation in system reliability is mainly affected by the failure mode of insufficient initial support strength. These findings provide quantitative guidance for the design, construction, and long-term maintenance of deep-buried tunnels in rheological rock. Full article

The increasing accumulation of poly(ethylene terephthalate) (PET) waste poses a significant environmental challenge and highlights the need for sustainable, value-added recycling strategies. In this study, porous carbon derived from PET was synthesized via carbonization and chemical activation and subsequently combined with manganese dioxide (MnO₂) to fabricate hybrid electrodes for aqueous supercapacitors. The PET-derived carbon exhibits a highly microporous structure with a large specific surface area and functions as a conductive and mechanically stable matrix that improves MnO₂ dispersion, charge transport, and electrochemical utilization. Systematic electrochemical investigations reveal strongly electrolyte-dependent charge-storage behavior. In an alkaline electrolyte, the capacitance is dominated by MnO₂ pseudocapacitive redox reactions, whereas in a neutral electrolyte, the response is primarily governed by electric double-layer charge storage. In a ferricyanide-containing redox-active electrolyte, additional electrolyte-mediated faradaic processes significantly enhance the apparent electrochemical performance. Under these conditions, the hybrid electrodes deliver a high apparent specific capacitance of 240–250 F g⁻¹ at moderate current densities. The electrodes further demonstrate stable cycling behavior and high apparent Coulombic efficiency, reflecting time-dependent utilization of both MnO₂ pseudocapacitance and redox-active electrolyte species during charge–discharge. Crucially, this work demonstrates that PET-derived carbon/MnO₂ hybrid electrodes exhibit complex, electrolyte-controlled charge-storage mechanisms and underscores the critical role of electrolyte selection in accurately interpreting electrochemical metrics and optimizing the performance of sustainable supercapacitors based on recycled polymer-derived carbons. Full article

In the context of the global sustainability agenda, firms are increasingly expected to incorporate environmental considerations into their global expansion strategies. However, existing studies mainly focus on formal institutions and economic factors, while the role of informal institutions remains underexplored. This study examines how Confucian cultural values influence Chinese firms’ outward foreign direct investment (OFDI), particularly their investment behavior in environmentally stringent host countries, such as Germany, Sweden, and Canada. Using panel data of Chinese A-share listed firms from 2009 to 2024, this study employs panel regression analysis to test the effects of cultural values, environmental pressure, and CEO power. The results show that cultural values are positively associated with both OFDI intensity and the likelihood of investing in environmentally stringent countries. In addition, environmental pressure strengthens this relationship, whereas CEO power weakens it. This study contributes to the literature on responsible global expansion by highlighting the role of informal institutions and firm-level characteristics. The findings also provide practical implications for policymakers and firms seeking to promote environmentally responsible international investment behavior. Full article

Against the policy backdrop of high-quality development and the “Dual Carbon” goals, corporate environmental responsibility and green governance have emerged as core drivers of corporate value creation and resource allocation in capital markets. However, in practice, corporate environmental disclosure has increasingly degenerated into an impression management tool. Using a sample of China’s A-share listed companies from 2011 to 2024, this paper combines text analysis of annual reports with green patent data to systematically examine the impact of performance feedback on corporate strategic environmental decoupling, drawing upon the behavioral theory of the firm and legitimacy theory. The findings are as follows: First, negative performance feedback significantly increases corporate greenwashing propensity, whereas positive performance feedback significantly strengthens corporate brownwashing behavior. Second, government regulation amplifies the costs of falsifying environmental information, significantly suppressing the positive impact of negative performance feedback on greenwashing, but exacerbating the positive impact of positive performance feedback on brownwashing. Conversely, media attention amplifies the benefits of corporate green performances, significantly strengthening the catalytic effect of negative performance feedback on greenwashing, while effectively suppressing the positive impact of positive performance feedback on brownwashing. Third, heterogeneity analysis reveals that the impact of performance feedback on corporate strategic decoupling in environmental disclosure is more pronounced among non-state-owned enterprises, firms facing high industry competitive pressure, and those in heavily polluting industries. By integrating greenwashing and brownwashing into a unified analytical framework, this study expands the research boundaries of corporate environmental disclosure and strategic behaviors. Furthermore, it deepens the application contexts of the behavioral theory of the firm within non-financial disclosure, deconstructs the myth of homogeneous governance effects under legitimacy pressure, and provides vital implications for investors, policymakers, and fund managers. Full article

Cash dividends, as a tangible form of monetary distribution, serve as a fundamental mechanism for remunerating investors for their capital commitments. Beyond manifesting a firm’s commitment to fulfilling its social responsibilities toward shareholders, such distributions potentially shape corporate deliberations regarding accountability toward a broader spectrum of stakeholders. Drawing on behavioral explanations of corporate decision-making, this study examines the association between cash dividend payouts and environmental protection tax burdens among Chinese A-share listed companies from 2018 to 2023. The empirical results indicate a significant and robust negative association between corporate cash dividend payouts and environmental protection tax burdens. Mechanism analysis suggests that this cross-domain behavioral consistency is primarily channeled through the proactive fulfillment of corporate environmental responsibilities. Further inquiry reveals that both government environmental subsidies and media coverage exert positive moderating effects on this relationship. Notably, this observed negative association is particularly pronounced in firms characterized by lower executive environmental awareness, those operating in regions with lenient environmental regulations, companies navigating economic downturns, and those situated within low-pollution industries. This research provides novel evidence for the “governance complementarity” hypothesis, suggesting that financial accountability and environmental stewardship are mutually reinforcing rather than mutually exclusive. Furthermore, it offers a pioneering micro-behavioral perspective on how firms in emerging economies can harmonize shareholder wealth distribution with green transition objectives. Full article

Artificial intelligence (AI) is increasingly integrated into corporate Environmental, Social, and Governance (ESG) strategies, yet employees’ psychological responses to this transformation remain underexplored. This study examines how AI-induced job anxiety influences employees’ evaluations of AI’s role in supporting ESG initiatives. Drawing on Challenge–Hindrance Stressor Theory and cognitive appraisal perspectives, we propose that technological anxiety may function as a cognitive–evaluative signal rather than merely a barrier to adoption. Using survey data from 858 employees of a major commercial bank, we test a structural equation model distinguishing cognitive appraisal from motivational and learning pathways. The results reveal a paradox: AI-induced job anxiety is positively associated with employees’ perceptions of AI’s effectiveness in ESG implementation (Estimate = 0.195, p < 0.001) but does not significantly increase intrinsic motivation or knowledge acquisition in either AI or ESG domains. Instead, employee motivation remains the primary driver of knowledge development. Our findings suggest that prior literature may have conflated attentional activation with behavioral adaptation. While anxiety can heighten cognitive vigilance, it does not necessarily provide the motivational or psychological resources required for knowledge acquisition. Full article

This work presents the design and evaluation of cerium and zinc oxide-incorporated indium oxide (Ce/ZnO-In₂O₃) nanocube composites synthesized via a hydrothermal process for advanced ethanol gas sensing. The incorporation of Ce and ZnO effectively modified the surface chemistry and electronic structure of In₂O₃ without causing significant morphological degradation. Compared with pristine In₂O₃, the Ce/ZnO-In₂O₃ sensor exhibited a significantly enhanced response of 33.2 toward 100 ppm ethanol at 300 °C, corresponding to an 8.7-fold improvement, along with a low detection limit of 0.8 ppm. In addition, the composite sensor demonstrated stable and reversible sensing behavior, excellent repeatability over 100 cycles, and long-term operational stability. Notably, improved humidity tolerance was achieved, with approximately 77% of the initial response retained at 80% relative humidity. The enhanced sensing performance is attributed to the combined effects of heterojunction formation between ZnO and In₂O₃ and Ce-induced lattice distortion, which promote oxygen adsorption and facilitate charge transfer during gas reactions. Principal component analysis (PCA) further confirmed the improved discrimination of ethanol against interfering gases. These results underscore the synergistic effects of Ce and ZnO incorporation in tailoring electronic structures and surface chemistry, thereby emphasizing the potential of this strategy for reliable ethanol detection in environmental and industrial applications. Full article

Certain clayey soils are susceptible to swelling and shrinkage due to moisture variations, which can lead to ground deformation and structural damage. Although traditional stabilization methods using lime and cement are effective, they involve high energy consumption and significant CO₂ emissions. In response to sustainability concerns, this study investigates the potential of in situ geopolymer stabilization of clay soils using industrial by-products as eco-friendly binders. Experimental studies were conducted on clay specimens stabilized with geopolymer binders produced from fly ash and waste brick powder activated by alkaline solutions. The selected clay exhibited stiff to very stiff behavior and was used as a reference material to ensure reliable evaluation without the influence of severe initial degradation. Reference samples with identical water content but without alkaline activation were also prepared. The primary objective was to assess geopolymers as a sustainable alternative to conventional binders, focusing on moisture sensitivity and long-term mechanical performance. Laboratory strength tests demonstrated that geopolymer-treated specimens exhibited significantly higher strength compared to untreated samples, indicating substantial improvement in engineering properties. Furthermore, Scanning Electron Microscopy (SEM) analyses revealed that the combination of dual activators (NS+NH) and thermal curing at 85 °C transformed the weak clay matrix into a dense, fibrous geopolymer network. However, the high curing temperature was primarily used to study the reaction mechanisms; the practical applicability of the method should be evaluated based on results obtained at ambient temperature. This structure enhanced particle bonding and mechanical interlocking by filling voids within the matrix. Overall, the findings confirm that geopolymer stabilization using industrial waste materials is an effective and environmentally sustainable alternative to conventional soil stabilization techniques, contributing to reduced carbon emissions in geotechnical engineering. Full article

With the demand for high-voltage electrical insulation systems increasing, the development of environmentally friendly anti-corona materials with reliable nonlinear electrical properties has become essential. In this work, a waterborne polyurethane/epoxy (WPU/EP) composite coating was fabricated using micron-sized SiC (α-SiC), nano-sized SiC (β-SiC), and n-ZnO as multi-scale fillers. Its microstructure, nonlinear conductivity, flashover characteristics, and electro-thermal aging performance were systematically investigated. The results indicate that the incorporation of α-SiC significantly enhances conductivity under high electric fields by forming conductive pathways, while β-SiC further improves nonlinear behavior through interfacial bridging effects. The addition of n-ZnO modifies interfacial characteristics and contributes to improved electrical response. Moreover, the flashover performance is strongly dependent on filler composition, showing a critical role of nano-fillers in charge trapping and transport regulation. Electro-thermal aging tests on simulated stator bars reveal that the developed coating exhibits improved resistance to degradation compared with conventional materials. These findings demonstrate the effectiveness of multi-scale filler design in tailoring the electrical and insulation performance of waterborne anti-corona coatings. Full article

Luminescent cellulose-based fibers are promising materials for anti-counterfeiting applications because they can provide covert and spectrally distinguishable optical signatures compatible with paper- and textile-based authentication systems. In this study, Lyocell fibers modified with selected inorganic and organic luminescent compounds were subjected to accelerated xenon-lamp aging in order to evaluate their functional durability under simulated environmental exposure. The effects of aging on the mechanical properties and luminescent behavior of the fibers were investigated. The results showed that accelerated aging led to a reduction in tensile strength and elongation at break for all fiber variants, although the extent of these changes depended on the type of modifier. Spectroscopic analysis indicated that, despite changes in emission intensity, the characteristic luminescent responses of the modified fibers remained detectable after aging. These findings suggest that luminescent Lyocell fibers can retain their practical identification potential under the applied test conditions and may be considered promising candidates for use as covert security elements. The observed stability is attributed to the immobilization of luminophores within the cellulose matrix and the intrinsic photostability of the applied luminescent systems. At the same time, the study highlights the need for further investigations into the structural and photophysical stability of such systems under long-term environmental exposure. Full article

Wear remains a dominant cause of performance loss and premature failure in mechanical components, motivating the development of environmentally benign surface-engineering solutions. Among thermal spray systems, high-velocity oxy-fuel (HVOF)-sprayed WC-Co coatings are widely applied under severe wear conditions. The development of nanophase coatings offers the potential for enhanced mechanical performance. However, retaining the nanostructure and limiting decarburization during deposition remain key challenges. In this study, nanophase WC-12Co feedstocks with two particle size ranges, together with Al-modified nanophase powders, were used to deposit coatings under optimized HVOF spraying conditions (spray distance 200 mm, reduced O₂/fuel ratio, and high particle velocity) and were benchmarked against a conventional WC-12Co (12 wt.% Co) coating. The coatings were characterized in terms of microstructure and phase constitution (OM, SEM/EDS, XRD) as well as thickness, porosity (0.5–3.6%), adhesion strength (up to 65 MPa), and microhardness (~1040–1210 HV). Tribological behavior was assessed by ASTM G99 pin-on-disk testing and counterbody wear was quantified via geometric volume loss estimations. The use of larger nanophase particles enabled effective nanostructure retention with limited decarburization, whereas reducing particle size intensified decarburization, promoting increased W₂C formation, and markedly reduced coating cohesion, despite lower porosity and higher hardness. Aluminum additions enhanced coating microhardness and suppressed Co₃W₃C formation, indicating improved phase stability with minimal additional decarburization. Although coating wear remained negligible for all systems, Al-containing coatings exhibited increased friction (up to 35%) and significantly higher counterbody wear (up to sevenfold) compared to the Al-free nanophase coating, which was found to correlate with coating microhardness. Overall, the results demonstrate that optimizing nanophase WC-Co coatings requires balancing competing mechanisms between microstructural stability, cohesive integrity, and tribological response, highlighting the critical role of feedstock design in tailoring coating performance. Full article

Ocean Literacy (OL), introduced in the early 2000s, refers to the essential knowledge individuals should acquire about the ocean by the end of formal education. Over time, the concept has expanded beyond cognitive understanding to include affective and behavioral dimensions that support attitudes and actions. Among these, emotional connections emerged as a significant driver of environmentally friendly behavior and represent a potential lever for educational practices. In this context, we conducted an informal survey involving 313 students (aged 8–12 and 14–15) living in a coastal area of northeastern Italy by means of a single open-ended question: “What is the sea to you?” Responses were analyzed through qualitative content analysis. Emotion-related expressions were the most frequent category (60.1%), followed by descriptive comments (42.8%), references to uses of the marine environment (35.8%), and statements identifying the ocean as a source of life (21.1%). Mentions of personal memories and references to the need for ocean conservation were less frequent. These findings suggest that, in our sample, frequent exposure to coastal environments may have fostered emotional connections with the ocean. Use of alternative teaching approaches (including technology-mediated ones) and further investigations into youths’ ocean connections could enhance the diffusion of OL in education settings. Full article

The remarkable ecological success of fungi is supported by their capacity for rapid and often reversible molecular responses to fluctuating environments. While conventional evolutionary theory has largely emphasized mutation and selection as central drivers of adaptation, many environmentally responsive fungal traits are also shaped by molecular processes that generate reversible phenotypic variation on ecological or developmental timescales. This review synthesizes current knowledge on reversible genetic and epigenetic mechanisms underlying fungal phenotypic plasticity by integrating insights from programmed genetic rearrangements such as mating-type switching, transposable element activity, variation in tandem repeats and the behavior of accessory chromosomes, together with dynamic epigenetic processes including histone modifications, DNA methylation, chromatin remodeling and RNA mediated regulation. Together, these mechanisms form an interconnected framework that enables rapid and, in many cases, reversible phenotypic diversification, although their consequences range from transient regulatory shifts to partially or fully irreversible sequence-level changes. We highlight the molecular machinery that governs reversibility and its evolutionary implications for fungal pathogenesis, symbiosis, and biotechnology. By uniting genetic and epigenetic perspectives, this review advances a holistic framework in which reversibility is treated as a key property of fungal phenotypic plasticity, helping fungi balance stability with flexibility under environmental challenge. Understanding these mechanisms provides new insights into fungal evolution, and opens new avenues for antifungal intervention and the rational design of industrially valuable fungal strains. Full article

Hydrochar application to soil inevitably releases hydrochar-derived dissolved organic matter (HDOM), yet its specific impact on soil microbial communities, independent of the hydrochar solid matrix, remains poorly understood. This study investigated, for the first time, the dose-dependent effects of HDOM on bacterial communities in three distinct soil types (red, yellow-brown, and black soils). A concentration gradient, including undiluted stock solution and 10-, 100-, and 1000-fold dilutions with ultrapure water, was established to test for hormesis-like responses. High-throughput 16S rRNA gene sequencing revealed that HDOM induced profound, soil-specific shifts in bacterial community structure. The application of HDOM induced the emergence of numerous specific bacterial taxa, with unique ASVs reaching up to 15,372. However, no significant changes were observed in microbial community richness or evenness (alpha diversity). Drastic shifts in beta diversity were evident only in red soil and yellow-brown soil, and exclusively under the undiluted HDOM treatment. At the phylum level, HDOM application did not alter the dominant bacterial types (top 10 phyla); however, their relative abundances were jointly regulated by both HDOM dose and soil type. Significant HDOM-induced changes in key bacterial biomarkers were primarily detected in red soil (e.g., phylum Elusimicrobia, class Fimbriimonadia, and family Alicyclobacillaceae) and yellow-brown soil (e.g., phylum Proteobacteria, class Alphaproteobacteria, and family Rhizobiaceae), while in black soil, such changes were observed only under the undiluted HDOM treatment (e.g., species Streptomyces rochei). Predictive functional profiling suggested limited impact on major metabolic pathways, with soil type remaining the primary determinant. These findings demonstrate that HDOM exerts a direct, dose-dependent, and soil-specific influence on bacterial communities, providing key insights into the environmental behavior of hydrochar and guiding its safe application. Full article

Conductive core–shell superabsorbent polymers (SAPs) are emerging as multifunctional additives for cementitious materials, combining moisture management with electrical functionality. In cement-based systems, a swellable polymeric core enables internal curing and crack-sealing through controlled water uptake and release, while a conductive shell introduces ionic and/or electronic charge transport, addressing key limitations of conventional non-conductive SAPs. This dual functionality provides a pathway toward smart cementitious composites with enhanced durability, self-sensing capability, and moisture-responsive behavior. This review focuses on the physical chemistry mechanisms governing conductive core–shell SAPs in cementitious environments, with emphasis on swelling thermodynamics, water transport kinetics, interfacial phenomena, and charge transport mechanisms. The roles of osmotic pressure, elastic network constraints, ionic effects, and pore solution chemistry are critically discussed, together with their impact on conductivity, hydration processes, microstructure development, and long-term performance. The relative contributions of ionic and electronic conduction are examined in relation to hydration state, shell morphology, and percolation of conductive networks. In addition, the relevance of core–shell SAP architectures to sustainable packaging is briefly discussed as a secondary application, illustrating how similar physicochemical principles—such as moisture buffering and functional coatings—apply beyond construction materials. Finally, key knowledge gaps are identified, including long-term stability in highly alkaline environments, trade-offs between swelling capacity and conductivity, environmental impacts of conductive phases, and the need for integrated experimental and modeling approaches. Addressing these challenges is essential for the rational design and practical implementation of conductive core–shell SAPs in next-generation cementitious materials. Full article