Search Results (1,196)

This study investigates hydrogen embrittlement in welded joints of X52 (L360) pipeline steel obtained from an operating natural gas transmission network after 31 years of service, with particular emphasis on production (longitudinal) and girth (circumferential) welds. The aim is to elucidate the influence of microstructural heterogeneity across the pipe wall and within different welded joint types on hydrogen transport, trapping behavior, and fracture mechanisms. The investigation combines X-ray diffraction, electrochemical hydrogen permeation testing, fractographic analysis, and transmission electron microscopy. X-ray diffraction results show that the base metal and girth weld consist predominantly of body-centered cubic ferrite, whereas the production weld additionally contains retained austenite associated with an elevated manganese content. These phase-related differences are consistent with transmission electron microscopy observations of martensite–austenite constituents within the weld microstructure. Electrochemical hydrogen permeation measurements reveal pronounced microstructure-dependent hydrogen transport behavior. The production weld exhibits a significantly lower apparent diffusion coefficient and a markedly higher hydrogen trap density, approximately five times greater than those of the base metal and girth weld, providing a mechanistic explanation for the observed differences in hydrogen uptake behavior. Fractographic analysis demonstrates a transition from ductile microvoid coalescence in the uncharged condition to predominantly brittle fracture following hydrogen charging. This transition is accompanied by a substantial increase in the fraction of brittle fracture zones, reaching approximately 53% in hydrogen-charged specimens. A pronounced gradient in hydrogen embrittlement susceptibility is observed across the pipe wall thickness, with outer-wall specimens consistently exhibiting greater susceptibility than inner-wall specimens. This behavior reflects the combined influence of long-term soil corrosion and hydrogen-assisted degradation. Transmission electron microscopy reveals that plastic deformation governs dislocation generation, while hydrogen significantly modifies dislocation behavior by promoting dislocation pile-ups near martensite–austenite constituents and non-metallic inclusions. These observations indicate strong interactions between hydrogen, dislocations, and microstructural heterogeneities. A clear size-dependent role of non-metallic inclusions is identified. Sub-micron inclusions act primarily as irreversible hydrogen trapping sites that contribute to hydrogen redistribution within the microstructure, whereas larger inclusions serve as preferential crack initiation sites under hydrogen charging conditions. Overall, the results demonstrate that hydrogen embrittlement behavior is governed by the combined effects of microstructural state, welded joint type, and long-term service-induced degradation, resulting in distinct hydrogen transport characteristics and fracture responses across the pipe wall. Full article

Host-finding behavior of insect herbivores is a key determinant of herbivory intensity in agricultural and forest ecosystems, which often drives excessive pesticide application for pest control. While host plant apparency theory explains herbivore host detection, and push–pull strategies manipulate this behavior, both produce inconsistent results and remain mechanistically disconnected. Existing frameworks like the Resource Concentration Hypothesis focus mainly on host density, ignoring the multidimensional, context-dependent nature of apparency. Here, we synthesize forest and agricultural research to develop the first unified framework linking these two concepts. We show that host plant apparency is not intrinsic but shaped by plant morphology, non-host identity, and spatial arrangement. Push–pull strategies exploit this relativity by redesigning the chemical and physical apparency landscape. We argue that: (1) push–pull system success requires reducing main crop apparency while enhancing trap crop apparency; (2) trap crops may fail when their dual functions, olfactory attraction or physical interception, are misinterpreted, with profound implications for spatial design; and (3) this integration resolves field contradictions by framing them within a common bottom-up mechanism. Our framework provides a generalizable principle for sustainable pest management: effective control depends on understanding what makes host plants apparent to target pests in their specific local environment. Full article

Direct current (DC) surface flashover on polystyrene (PS) remains a critical bottleneck that impedes its reliable application in high-voltage insulation apparatus. To circumvent the protracted processing durations and stringent film-forming conditions inherent in conventional surface modification techniques, this study proposes a novel “liquid-film-assisted in situ rapid plasma curing” strategy. By harnessing atmospheric-pressure dielectric barrier discharge (DBD) technology within an argon ambient, the rapid (<6 min) and efficient deposition of a fluorosilane (FAS-13) functional coating onto the substrate was achieved. Microscopic characterizations coupled with isothermal surface potential decay (SPD) measurements reveal that this coating substantially mitigates the detrapping and surface migration of charge carriers. Macroscopic DC flashover testing corroborates that, under the optimal modification ratio, the surface breakdown voltage of PS is elevated to 14.04 kV, yielding an insulation gain of 26.94%. To elucidate the underlying physical mechanisms, density functional theory (DFT) calculations were conducted, revealing that the energy band misalignment between the wide-bandgap fluorinated layer and the substrate facilitates the construction of a high-density deep trap network (with a depth of ~0.8 eV) at the coating–substrate interface. By robustly anchoring primary electrons and inducing the formation of a homopolar space charge shielding layer, these deep traps physically arrest the evolution of the secondary electron emission avalanche (SEEA). Consequently, this work not only establishes a viable engineering framework for the rapid, large-scale surface reinforcement of DC insulation equipment but also provides profound quantum chemical insights into interfacial trap regulation within all-organic dielectrics. Full article

Rural e-commerce is treated as a lever for common prosperity, but its welfare effect turns non-monotonic across digital-development gradients, raising concerns about the widening urban–rural gap in sustainable regional development. We built a county-year panel of 2725 Chinese counties from 2014 to 2022, with Taobao village density as the treatment, land-based agricultural value conversion efficiency as the county-level mediator, and the Peking University digital financial inclusion digitization sub-index as the moderator. The estimations combine two-way fixed-effect regressions, continuous-interaction moderation, Hansen panel-threshold regression, Callaway–Sant’Anna difference-in-differences, Bartik shift-share instrumentation with Rotemberg-weight diagnostics, and multiple imputation by chained equations supplemented by propensity-score sensitivity checks. Taobao village density linearly depresses rural per-capita disposable income and produces a significant U-shape in the nightlight Gini with an in-sample turning point. The marginal effect on Sen welfare moves from approximately $+0.99$ log-units at low digitization to approximately $-0.95$ at high digitization, with the sign-reversal becoming statistically significant only above the 55th percentile of the moderator (Hansen threshold at the 85th percentile), so the trap is a tail regime rather than a generalized reversal; over the panel window, however, 80.5% of counties cross into the trap zone in at least one year. Approximately 28 percent of the welfare squeeze passes through the land-based ecological efficiency channel, with parallel mediators delivering 19–90 percent. The deepest squeeze appears in cash-crop counties that platform theory predicted to benefit most, where the welfare effect at high digitization is roughly $3.1$ times the staple-grain effect. We label this pattern the Digital Saturation Trap and argue that sustainable urban–rural policy should shift from uniform platform access toward differentiated platform governance in counties beyond the saturation threshold. Full article

Laser-induced breakdown in water-rich biological media results from the interplay between primary photoionization processes and avalanche amplification of free electrons. Understanding this competition is essential for predicting ablation thresholds under ultrashort-pulse irradiation. In this work, we develop an analytical rate-equation model for the buildup of electron density in water-like biological tissues. It combines photoionization and chromophore ionization into a single seed-generation term, while avalanche ionization is described through a cascade gain factor. This formulation provides a framework for describing cascade electron-impact ionization processes in liquid-like media under strong-field excitation. Our approach gives an analytical expression for the temporal evolution of electron density driven by a Gaussian laser pulse and makes it possible to separate the contributions of direct ionization of water and ionization of chromophore centers. The analytical results are compared with numerical simulations that include carrier diffusion, bimolecular recombination and trapping. The comparison clarifies the roles of seed formation and cascade amplification in the growth of the electron population. The predicted dependence of threshold fluence on pulse duration agrees well with experimental data reported for water-like tissues such as the corneal tissues at a wavelength of 800 nm. The model provides a simple analytical picture of ultrafast plasma formation and electron-driven energy deposition in water-like biological media. Full article

Hydrogen embrittlement is a critical degradation mechanism in microalloyed and pipeline steels used in hydrogen-economy infrastructure. We present a physics-informed neural network (PINN) framework that embeds Fick’s second law and the Arrhenius temperature dependence directly into the loss function, trained on 22 temperature-dependent data points spanning pure α-Fe and API X65 pipeline steels (modern and vintage microstructures). The PINN recovered the pure-iron activation energy (4.2 kJ mol⁻¹ vs. literature 4.15 kJ mol⁻¹, R² = 1.00) and yielded Arrhenius activation energies of 28.5 and 45.2 kJ mol⁻¹ for modern and vintage X65, respectively, indicating substantially stronger trapping in older microstructures. McNabb–Foster analysis of ten ternary Fe–Me–C,N alloys revealed flat-trap binding enthalpies of 19 ± 2 kJ mol⁻¹ and deep-trap free energies of 57 ± 2 kJ mol⁻¹, with effective diffusivities spanning three orders of magnitude governed primarily by flat-trap density. The framework provides a computationally efficient and physically consistent tool for hydrogen transport prediction, with a clear roadmap for multi-feature extension incorporating compositional and microstructural descriptors. Full article

The escalating demand for high-performance dielectric energy storage materials in pulse-power systems and portable electronics calls for polymer film capacitors with high discharged energy density and breakdown strength. Conventional polymers, however, suffer severe performance degradation under concurrent thermal and electrical stress, and existing reinforcement strategies—involving inorganic nanofillers or chemical crosslinking—often compromise flexibility, introduce interfacial defects, or involve complex processing. Herein, we demonstrate that incorporating a rigid mechanically interlocked molecule, specifically an octacationic homo[2]catenane, into a polyimide matrix yields robust, crosslink-like networks through strong [π∙∙∙π] electrostatic interaction between electron-rich aromatic units of polyimide and electron-deficient homo[2]catenane. This supramolecular network simultaneously enhances breakdown strength via densified chain packing and suppresses conduction loss by forming deep electron traps derived from the high electron affinity of homo[2]catenane. The optimized PI–HC⁸⁺ composite achieves a high discharged energy density of 7.86 J/cm³ with an efficiency > 80% and sustains stable performance over 10⁵ charge–discharge cycles at 150 °C. This research establishes mechanically interlocked molecules as a new class of functional fillers for high-performance polymer dielectrics, opening an unexplored avenue in the design of next-generation capacitive energy-storage materials. Full article

When the global energy transition is analyzed through economic lenses, the constraints imposed by the laws of thermodynamics are often overlooked. This study addresses the Latecomer’s Dilemma—the predicament of semi-peripheral nations compelled to decarbonize without the capital stock accumulated following the example of the countries of the Global North during their more than two hundred years of industrial development associated with the saturation of the atmosphere with carbon dioxide. A novel phase space model of the Anthropocene is constructed, synthesizing the political concept of ecological debt with the biophysical reality of entropy debt. The application of the laws of systems ecology and non-equilibrium thermodynamics enables the mapping of national development trajectories against the saturated “atmospheric bathtub”. The analysis identifies a critical Injustice Gap—a region of phase space physically foreclosed by historical emissions. Moreover, it has been demonstrated that a circular economy powered by low-density renewables functions as an entropy trap, converting material debt into radiative debt without achieving a closed loop. Consequently, the Polish correction vector is proposed as a stabilization mechanism. This study’s findings indicate that addressing the emerging phenomenon of adaptation apartheid necessitates the implementation of a high-density energy flux, namely Generation IV nuclear reactors, which would be funded by a retroactive ETS3 mechanism. This approach fulfills the thermodynamic condition for material closure, thereby substantiating the notion that energy justice constitutes a physical necessity for planetary stability. This study quantifies the historical radiative debt of a single early-industrialized hub (Manchester) at approximately 142.8 billion EUR. The novelty lies in the synthesis of biophysical laws and the Latecomer’s Dilemma through the proposed ETS3 mechanism. Full article

Agricultural crop residue burning is a major driver of seasonal PM2.5 pollution and greenhouse gas (GHG) emissions in Northern Thailand. This study quantified GHG emissions from the open burning of rice, maize, and sugarcane residues across six provinces (Chiang Mai, Mae Hong Son, Lampang, Uttaradit, Nakhon Sawan, and Kamphaeng Phet) from 2019 to 2024 using the 2006 IPCC emission methodology. Spatiotemporal patterns of fire hotspots were characterized using MODIS and VIIRS satellite data, combined with kernel density estimation (KDE) and land-use classification in ArcGIS Pro. Total non-CO₂ GHG emissions (CH₄ and N₂O, expressed as CO₂-eq using GWP100 from IPCC AR5) over the six years totaled 2,599,551 tCO₂-eq, with major rice contributing the largest share (35%), followed by sugarcane (24%), second rice (21%), and maize (20%). Nakhon Sawan was the leading emitter (41%), reflecting its extensive rice and sugarcane cultivation. Pearson correlation analysis revealed consistently positive relationships between daily fire hotspot counts and PM2.5 concentrations (r = 0.30–0.84), with the strongest correlations observed in Mae Hong Son, where basin topography traps pollutants. Time-series analysis confirmed pronounced seasonal PM2.5 peaks that exceeded Thailand’s 24-h NAAQS limit (37.5 μg/m³) by 7–9 times in severe years. Biochar production via pyrolysis was evaluated as a zero-burning alternative, with an estimated annual carbon sequestration potential of 2.3–3.5 million tCO₂-eq, substantially exceeding emissions from open burning. These findings indicate that crop-residue valorization options—including biochar production, composting, and biochar co-compost—could theoretically offset agricultural GHG emissions and reduce field-burning PM2.5 emissions in Northern Thailand. However, the realized mitigation will depend on (i) verification of biochar long-term stability in tropical Thai soils through dedicated in situ trials, (ii) economic incentives that offset biochar production costs of approximately 1500–3500 THB per tonne, and (iii) integration within a policy mix that combines burning bans, mechanization support, and farmer extension services. Without these enabling conditions, biochar should be regarded as a future-perspective option rather than an immediately deployable solution. Full article

Epoxy/BaTiO₃ nanocomposites with varying filler contents of BaTiO₃ were prepared and characterized for flexible DC insulation applications such as IGBT. Their breakdown strength under DC, AC, and 10 kHz voltage, tensile properties, dielectric response, surface potential decay, temperature-/electric field-dependent conductance, and field grading capability were investigated. Results show that loading BaTiO₃ increases the dielectric constant and alters loss behavior due to enhanced interfacial polarization and modified charge transport. However, breakdown and tensile strengths decrease monotonically with filler content, which is attributed to interfacial heterogeneity and local field distortion. Shallow-trap density rises while trap energy level declines with higher BaTiO₃ loading, promoting charge trapping–detrapping. Electrical conductivity of epoxy/BaTiO₃ nanocomposites increases with both electric field and temperature, while simulation of electric field distribution in the triple point of IGBT encapsulation reveals that the increased permittivity and conductivity with BaTiO₃ content can reduce the maximum local electric field by up to 6.7% and 13.7% for the two kinds of typical structure of triple points, respectively. Thus, nano-BaTiO₃ effectively tailors dielectric response and charge transport but introduces interfacial complexity that degrades breakdown and mechanical performance. However, a trade-off between intrinsic insulation, tensile strength, and field grading capability can be obtained. This work offers experimental insights for designing epoxy-based encapsulation materials with tunable electrical properties for flexible DC systems. Full article

The durian seed borer, Mudaria stahlgretschae, is a major economic pest that has significantly impacted durian cultivation in Southeast Asia; however, comprehensive biological and ecological data for this species remain limited. This study employs an integrative taxonomic approach, combining morphological examination with molecular validation of the mitochondrial cytochrome c oxidase subunit I (COI) gene. Phylogenetic analysis (Neighbor-Joining) confirmed that all collected specimens (n = 11) formed a distinct monophyletic clade within the genus Mudaria, showing a genetic identity of 95.75–96.85% with existing GenBank accessions, thereby confirming their identity as M. stahlgretschae. Systematic monitoring using light traps in Uttaradit Province revealed a clear seasonal phenology, with adult flight activity restricted to a five-month period from April to July 2025. Population density peaked in May (55.56%), synchronized with the mid-stages of durian fruit development. Furthermore, chemical profiling of female gland volatiles via GC-MS identified 40 compounds; among these, four putative sex pheromone candidates—1-Hexacosene, (Z)-7-Hexadecenal, 11-Octadecenal, and 2-Hexadecanol—were identified as key constituents based on their consistent detection across all replicates (n = 3), high relative abundance, and absence in male extracts or blank controls. These findings establish a critical foundation for developing synthetic pheromone lures and synchronized monitoring programs, offering a robust framework for the sustainable management of M. stahlgretschae in durian agroecosystems. Full article

Josephson junctions are key elements in superconducting qubits. Their efficient wafer-scale characterization is crucial for process control and optimization, motivating analysis approaches that extend beyond conventional cryogenic measurements. In this work, we demonstrate that room temperature (RT) capacitance and current–voltage measurements, combined with appropriate data analysis, enable extraction of relevant junction parameters such as oxide thickness, tunnel coefficient, and interfacial defect density. Furthermore, different charge transport mechanisms can be identified from detailed current–voltage analysis. We evaluate our characterization technique using tunnel junctions fabricated on 200 mm wafers in a complementary metal–oxide–semiconductor (CMOS)-compatible subtractive process. The results show a homogeneous average oxide thickness across the wafer with a variation below 3%. A dependence of the tunnel coefficient on oxide thickness indicates a stoichiometry gradient within the oxide. Additionally, low interfacial defect densities in the range of 70–5000 defects/cm² are observed in our junctions, increasing with decreasing oxide thickness, suggesting that wet etching used for thickness control introduces interfacial trap states. Our study highlights the importance of advanced RT characterization for extracting tunnel junction parameters on the wafer scale, enabling effective process monitoring and optimization in industrial superconducting qubit manufacturing. Full article

Accurate estimation of dynamic environmental phenomena through intelligent sensing systems plays a critical role in enabling reliable monitoring and decision-making in complex real-world scenarios. With the rapid development of artificial intelligence-driven sensing technologies and Internet of Things systems, modern agricultural monitoring is evolving from isolated data acquisition toward intelligent, multimodal perception and decision-making. However, traditional approaches predominantly rely on single data sources, making it difficult to simultaneously capture plant phenotypic variations and environment-driven mechanisms, thereby limiting model applicability in complex field scenarios. To address this issue, a multimodal pest density estimation framework, namely the Pest Density Estimation Framework (PDEF), is proposed, which integrates UAV-based imagery, trap monitoring data, and environmental sensor measurements. In this framework, crop canopy damage features are extracted using convolutional neural networks, while temporal encoding is employed to model dynamic environmental variations. Cross-modal feature alignment and environment-aware enhancement mechanisms are further introduced to achieve deep integration of multi-source information, enabling the construction of a unified feature representation space and improving estimation accuracy. Extensive experiments conducted on a constructed multimodal agricultural dataset demonstrate that the proposed method achieves MAE, RMSE, and MAPE values of $5.47$, $7.62$, and $14.9\%$, respectively, significantly outperforming the Transformer-based fusion model (MAE $6.01$, RMSE $8.16$). Meanwhile, the coefficient of determination reaches $R^2=0.84$, indicating superior fitting capability and stability. In multimodal combination experiments, the three-modality fusion reduces error metrics by more than $20\%$ on average compared with single-modality models, validating the effectiveness of multi-source collaborative modeling. From the perspective of integrating plant phenotypic analysis and environmental perception, this study provides a novel AI-driven intelligent sensing framework for pest monitoring and crop management, contributing to improved pest prediction capability and enhanced intelligence in agricultural production systems. This study further provides practical implications for agricultural economics and supply chain optimization by enabling data-driven decision-making through intelligent sensing systems. Full article

In the northern Norwegian North Sea, the Lower Paleogene post-rift succession constitutes an underexplored interval with considerable potential for stratigraphic petroleum plays. Nevertheless, predicting its subsurface prospectivity remains hindered by persistent uncertainties in facies architecture, depositional heterogeneity, and reservoir quality. To address these uncertainties, the present study integrates relative geologic time (RGT)-based seismic stratigraphic interpretation, spectral decomposition, sedimentary facies analysis, and litho-saturation assessment, primarily constrained by seismic and well-log datasets, to evaluate the Paleocene post-rift Lista Formation in the northern Norwegian North Sea. The results reveal the presence of Paleocene mass-transport deposit (MTD) complexes associated with axial lobe sandstones of submarine fan systems. These MTD complexes exhibit pronounced vertical and lateral facies transitions into low-density turbidites, debrites, and hemipelagic drapes, together forming an effective stratigraphic framework for hydrocarbon entrapment. Although the Lista submarine-fan sandstones are relatively thin, typically ranging from a few centimeters to decimeters in thickness, they display favorable reservoir characteristics. Litho-saturation analysis indicates preserved porosity and low water saturation (<20%), supporting their potential as effective hydrocarbon storage intervals. Distal fan-lobe sandstones, despite their limited thickness, show encouraging reservoir quality, whereas thicker low stand systems tract (LST) accumulations and time-equivalent carbonate mound complexes appear to have developed within more proximal structural domains. This proximal-to-distal facies organization reflects the dynamic interaction between tectonically inherited accommodation space and sediment-routing pathways during the early Paleocene. Overall, the findings highlight the significant petroleum prospectivity of the Paleocene post-rift succession in the northern Norwegian North Sea. The stratigraphic juxtaposition of sand-prone submarine-fan lobes against hemipelagic sealing intervals, combined with heterogeneity imposed by syn-rift structural inheritance, generates a highly favorable architecture for stratigraphic trapping. More broadly, the integrated workflow presented here enhances the predictive mapping of subtle stratigraphic traps within post-rift successions and provides a robust framework for reducing exploration uncertainty in analogous basins. Full article

Mass trapping of adult mosquitoes is increasingly promoted as an environmentally friendly alternative to insecticide-based vector control, yet quantitative evidence for its long-term population-level effects remains limited. We analyzed adult Aedes mosquito Biogents trap data from four tropical islands (three in the Maldives, one in the Philippines) where mass trapping was implemented at different trap densities. Using equilibrium-constrained population models, we describe how adult Aedes populations differ across trap densities, with outcomes ranging from partial suppression to near-zero levels at higher trap densities. At low to intermediate densities (4–6 traps·ha⁻¹), populations stabilized at non-zero equilibrium levels, whereas operational elimination was consistently observed at densities ≥ 10 traps ha⁻¹. A descriptive curve is shown to illustrate the decline in equilibrium abundance with increasing trap density, while a conceptual sigmoid model is used to illustrate how a transition in the recruitment–removal balance may occur under theoretical conditions. Limited larval source management was implemented on two islands, but elimination was also observed in the absence of larval interventions, indicating that sustained adult removal appears to have been the dominant driver of suppression. These findings indicate that mass trapping, when deployed at sufficiently high densities, is associated with rapid declines to near-zero population levels and may serve as an effective component of integrated vector management, particularly in geographically bounded settings or as a rapid-response intervention during outbreaks of arboviral diseases. Full article