Search Results (8,651)

Close-distance multi-seam mining frequently induces secondary surface deformation and subsidence. Extracting a lower coal seam beneath an existing goaf repeatedly disturbs the overburden, often leading to roof collapse and the expansion of vertical water-conducting fractures that connect the working face to aquifers. Furthermore, the overlying goaf increases the risk of water inrush into active lower workings. This study investigates the mechanisms of strata reactivation and fracturing within an overlying goaf during lower seam extraction at a mine in Northwest China. Using theoretical analysis, numerical simulation, and microseismic monitoring, the research examines the secondary fracture mechanisms of the goaf roof and the resulting water-inrush potential. Research Findings: Strata Instability: Analysis of the key sandstone strata indicates that subsidence (W) of the key rock blocks satisfies 3.17 < W₁ = 4.61 m < 18 m for the lower seam and 3.17 m < W₂ = 5.31 m < 69.6 m for the 3-1# seam. These values confirm that key rock blocks in the basic roof undergo “reactivated” instability following fracture during lower seam mining. Pressure Relief and Fluid Dynamics: Mining-induced fracture initiation and propagation trigger strata reactivation. As the distance to the center of the goaf decreases, the subsidence of the overburden increases, ultimately resulting in a “trapezoidal” bending deformation pattern. Due to secondary activation, the roof subsidence 30 m above the 221 coal seam increased from 1.89 m to 5.475 m. The layers of high-strength, medium-grained sandstone and siltstone overlying the 317 coal seam and beneath the 221 goaf serve as high-strength material for the overlying rock formations. This suppresses the development of the caving zone and fracture zone, leading to subsidence failing to reach the sum of the heights of the two coal seams (6.8 m) and only reaching a value of 5.475 m. During extraction, the stress field undergoes a distinct evolution: it transitions from an initial “regular triangular” pressure-relief zone into a tripartite “weak–strong–strong” distribution. Furthermore, fluid discharge in the overlapping zone between the 317 working face and the 221 goaf increased sequentially, displaying an “alternating” pattern of peak vector variations as the face advanced. Microseismic Activity: Monitoring within the 300–500 m range identified frequent low-energy events and high-magnitude events (10⁴ J, 10⁵ J). These findings demonstrate that secondary excavation directly impacts the aquifer, creating a significant water-inrush hazard for the active working face. Full article

The building sector has a significant environmental impact throughout the life cycle of a building. Reducing the environmental load of the building sector is essential for creating a sustainable society. Many current reports focus on carbon emission, while other environmental impacts remain insufficiently evaluated. Furthermore, buildings serve different functions depending on the region, and the types and quantities of primary materials used vary accordingly. Under these circumstances, little research has focused specifically on Japan. This study conducted a life cycle assessment (LCA) covering the life cycle of material inputs (structural and finishing materials) for 95 buildings in Japan. In addition to greenhouse gas emissions, multi-criteria analysis, including characterization and integration (characterization such as acidification, ozone layer destruction, and photochemical ozone; damage assessment; and integration using LIME2 and LIME3), was conducted. Based on analyses of numerous buildings, the objectives were to clarify trends in environmental impact emissions by building use, conduct an environmental impact analysis that could serve as a future benchmark, and discuss for reducing these environmental impacts. First, the analysis of trends such as maximum, median, and minimum values across six building types revealed that the environmental impact per square meter tended to be lower for production and logistics facilities and higher for offices, government buildings, schools, hospitals, hotels, and condominiums across many indicators. However, significant variations were observed between individual buildings within each category. These results can serve as a benchmark for the environmental impact of future buildings in Japan. Next, GHG emissions and integration (LIME2, LIME3) were quantitatively identified for materials with high emissions, and the factors were considered. Furthermore, processes with high environmental impacts associated with the material were analyzed and identified. Ready-mixed concrete, reinforcing bars, and steel frames showed high values across quantitative indicators, whereas wood and other materials varied by indicator. Finally, based on these findings, perspectives for reducing the environmental impact of key materials are proposed for each stakeholder group. Full article

Due to phenomena, such as refraction, reflection, and light scattering, the three-dimensional (3D) reconstruction of transparent objects with complex geometric symmetry or contours is confronted with the challenges of insufficient extraction of feature points and recognition of contour detail. To solve this challenge, a novel reconstruction method based on multi-cooperative Neural Radiance Fields (NeRF) is proposed in the paper. This method incorporates angular offset fields and local reconstruction fields, explicitly modeling the effects of refraction and reflection during light propagation. The angular offset field simulates the internal refractive deflection within transparent materials, while the localized reconstruction field performs secondary reconstruction in regions affected by specular reflection. This approach effectively captures surface contours of transparent objects and accurately reconstructs scene details. Experimental results demonstrate that our method achieves approximately 10% improvement in reconstruction accuracy compared to traditional neural radiance field techniques, with a PSNR of 25, an increased SSIM of 0.87, and a reduced LPIPS value of 0.365. The proposed method offers a new perspective for reconstructing transparent objects and scenes containing such materials, holding significant theoretical and practical value. Full article

Reciprocating compressor air volume control systems have been extensively investigated, with a primary objective of reducing energy consumption and associated carbon footprints. As a multi-actuator system, failures in this energy-efficient configuration can trigger severe operational disruptions with cascading consequences. To address this, we initially constructed numerical models of the multi-actuator energy-efficient system to decode the variational patterns of compressor dynamic pressure pulsations and connecting-rod small-end bush tribological behaviors under partial actuator fault conditions, thereby establishing foundational data for fault degradation stratification. Building upon this, we propose a Prognostics and Health Management (PHM) algorithm using fault degradation analysis, thereby materializing self-recovery functionality in response to various fault conditions. Experimental validation demonstrates that the self-recovery algorithm successfully contained deterioration propagation through proactive intervention. The system achieved autonomous healing within 8 s (mild faults) and 13 s (moderate faults), constraining discharge fluctuations and vibration amplitude within allowable thresholds. This study establishes a solution framework for preserving multi-actuator energy-efficient systems’ health, accuracy, and economy. Full article

The degradation of building foundations, underground structures, and historical fabrics in sulfate-laden environments poses a persistent threat to the durability and safety of the built environment. Developing effective, sustainable repair materials is of paramount importance. This study presents the development, systematic optimization, and performance validation of a novel micro-expansive grout designed for high durability in aggressive sulfate conditions. The grout formulation utilizes industrial by-product fly ash, quicklime, and site-compatible soils, emphasizing sustainability. Nine chemical admixtures were screened for sulfate resistance enhancement. Laboratory experiments rigorously characterized the effects of water-to-solid ratio and admixture dosage on fresh-state properties (fluidity, setting time) and hardened-state performance (volumetric stability). To resolve a multi-objective optimization problem balancing injectability, dimensional compatibility, and cost-effectiveness, an integrated multi-criteria decision-making (MCDM) framework combining FAHP, MII, CRITIC, and TOPSIS was employed. This data-driven methodology identified an optimal formulation incorporating 3% disodium hydrogen phosphate (DSP) at a 0.58 water-to-solid ratio. The optimized grout exhibited a flow value of 75 mm, ensuring excellent injectability within the target range (40–120 mm), and an expansion rate of 7.67%, which falls within the safe range (0–10%) to ensure dimensional compatibility. Accelerated durability tests via cyclic immersion in sodium sulfate solution demonstrated the optimized grout’s exceptional resistance to sulfate attack, retaining approximately 88% of its compressive strength after 15 aggressive cycles. The balanced properties and validated durability indicate strong potential for this grout in demanding repair scenarios. One key example is the repair of fissures in earthen heritage structures, which requires extreme material compatibility and long-term performance. Full article

Domestic cats are among the most popular companion animals worldwide, with steadily increasing ownership and life expectancy. Paradoxically, despite their high prevalence and shared environmental exposures with humans, cats remain markedly underrepresented in molecular oncology research. Cancer is a leading cause of feline mortality, and alimentary lymphoma (AL) has emerged as one of the most common feline malignancies, yet its molecular landscape remains poorly characterized. This review summarizes current knowledge on feline AL, including epidemiology, risk factors, classification schemes, diagnostic challenges, treatment outcomes, and survival, with particular emphasis on low-grade alimentary lymphoma (LGAL), the most prevalent subtype. We discuss the complex relationship between chronic inflammatory enteropathies and lymphoma, highlighting diagnostic ambiguities and the inflammatory–neoplastic continuum. Importantly, we provide a critical overview of existing genomic, transcriptomic, epigenomic, proteomic, and metabolomic studies in feline AL, revealing a striking paucity of high-throughput, multi-omics analyses based on clinical material. Recent advances in feline genome assembly and annotation offer new opportunities to address these gaps. Furthermore, we compare feline AL with its human gastrointestinal T-cell lymphoma counterparts, demonstrating substantial molecular homology across key oncogenic pathways, including JAK/STAT signaling. This comparative perspective underscores the potential of feline AL as a naturally occurring model for the human disease. We conclude that comprehensive molecular characterization of feline AL is urgently needed to improve diagnostics, prognostication, and targeted therapies, with likely translational benefits for both veterinary and human oncology. Aim: The goal of this review is to summarize the current knowledge on feline alimentary lymphoma, including its origin, risk, classification, treatment approaches, and especially molecular landscape, which still remains poorly investigated with modern high-throughput techniques. Full article

The public-goods nature of ecological products and heterogeneous stakeholder interests mean that protected areas often face weak coordination, limited incentives, and uneven benefit distribution in the identification, transformation, and return of ecological value. Under increasingly strict conservation objectives, ecological product provision is shifting from direct resource use towards maintaining ecosystem functions and realising experiential value. This helps safeguard ecosystem integrity but raises demands on institutional pathways for value transformation and on the sustainability of community livelihoods. Using Pudacuo National Park in China as a case, this study develops an analytical framework linking supply–demand structures, value chains, and value co-creation, and applies policy document analysis, semi-structured interviews, field observation, and process tracing to examine mechanisms of ecological value realisation under strict conservation. The results show that: (1) a collaborative governance network integrating park authorities, local governments, and concession operators provides a stable organisational basis for ecological value identification and transformation; (2) strengthened provision of non-material ecological products reorients the supply system towards regulating and cultural services, driving a shift from material output to function- and experience-oriented provision; (3) a multi-level community participation model combines labour embedding, livelihood diversification, and institutionalised benefit return to form an ecological value return mechanism grounded in value co-creation. Together, these mechanisms support a relative balance between ecological protection and community development under strict protection and offer empirical insights into the institutional logic of ecological value realisation in strongly protected contexts. Full article

Large-scale use of reclaimed asphalt pavement (RAP) is limited by strong gradation variability, uneven recovery of aged asphalt (AA), and an incomplete understanding of the rejuvenation mechanism. This study combines source evaluation, composite rejuvenation, and multi-scale analysis to improve AA recovery. A gradation variability model was developed using the t-distribution, and a reliability-based method was proposed for reclaimed material selection and mix design. Rejuvenator 1 (R1) was identified as the best option, and a ternary composite rejuvenation system was formed using R1, SBS-modified asphalt, and base asphalt (BA). AA performance was assessed using physical and rheological tests, supported by Fourier-transform infrared spectroscopy, fluorescence microscopy, and gel permeation chromatography. The t-distribution guarantee rate method quantified RAP gradation fluctuations effectively. At a 90% guarantee rate, the deviation in key sieve pass rates was below 3%, indicating stable sources. In the composite system, 10% R1 restored AA high temperature performance, while adding 30% SBS modified asphalt and BA improved low-temperature crack resistance. The micro analyses showed no new functional groups after rejuvenation. Recovery was mainly driven by physical blending, dilution, and optimisation of the molecular-weight distribution. Full article

Microfluidics provides precise control of microscale fluid transport and has become central to biomedical, pharmaceutical, and industrial technologies. However, conventional fabrication methods such as photolithography and soft lithography require cleanroom facilities, use costly materials, and offer limited capability for constructing complex or multi-material architectures. This review highlights emerging manufacturing strategies, focusing on polymer-based micro-milling as an accessible and cost-effective alternative for microfluidic device production. Advances in micro-milling now enable the fabrication of microchannels and functional features with improved dimensional accuracy and surface quality, while additive manufacturing offers complementary rapid prototyping and design flexibility. Micro-milling is particularly promising for rapid prototyping of polymeric biosensor chips designed for point-of-care diagnostics. The technique supports diverse materials and eliminates reliance on cleanroom processing. Critical parameters, including tool geometry, spindle speed, and feeding rate, strongly influence fidelity and surface roughness, which directly affect biosensor sensitivity. Despite its advantages, challenges such as tool wear, burr formation, and limits on minimum feature size continue to hinder reproducibility. Recent progress in toolpath optimization, hybrid additive–subtractive methods, and real-time process monitoring shows the potential to overcome these barriers. Overall, micro-milling offers a scalable and economical route for fabricating accessible microfluidic and biosensing platforms, with future work needed to standardize processes and improve integration with surface functionalization methods. Full article

To mitigate the entanglement, agglomeration, and unstable conveying of high-moisture rice residues during stubble crushing for field incorporation, a discrete element method (DEM)-based modeling and optimization framework was developed to enhance the performance of a stubble-crushing device under wet paddy-field conditions. The device structure and kinematics were first analyzed, and the physical and mechanical properties of the residues were obtained through field measurements. A hollow wet–flexible straw model was then proposed to account for both mechanical breakage and moisture-induced adhesive interactions. Key contact and material parameters were calibrated using DEM simulations coupled with laboratory shear and three-point bending tests, showing good agreement with experimental trends. The validated model was subsequently extended to the device scale to characterize the cyclic capture–acceleration–throwing behavior of residues inside the crushing chamber. The individual and interactive effects of rotor speed, forward speed, and throwing-chamber clearance on comminution efficiency and conveying stability were investigated. A multi-objective response surface optimization identified an optimal parameter combination of 2000 rpm rotor speed, 0.87 m s⁻¹ forward speed, and 10.5 cm clearance. Under these conditions, the comminution rate reached 96.94%, and the coefficient of variation in throwing uniformity was 8.71%. Field validation further confirmed the reliability of the simulation results, with relative errors below 6%. Overall, the proposed framework provides an effective tool for the design optimization and parameter selection of wet-residue comminution equipment. Full article

Polysaccharide–protein composite hydrogels have demonstrated remarkable potential in targeted gastrointestinal delivery owing to their excellent biocompatibility, adjustable physicochemical characteristics, and intelligent responsiveness. This review provides a comprehensive overview of the underlying mechanisms and diverse applications of these composite hydrogels in gastrointestinal targeted delivery, with a particular emphasis on their stimuli-responsive release behaviors triggered by internal and external factors such as pH, enzymes, magnetic fields. Special attention is also given to their advantages in protecting sensitive bioactive ingredients, including curcumin, EGCG, probiotics. Furthermore, this review highlights their capabilities in achieving high encapsulation efficiency, smart controlled release and targeted delivery, while also presenting current challenges associated with material stability, targeting precision, large-scale production, and clinical translation. Finally, future perspectives are discussed, focusing on the development of multi-response system design, innovative biomaterials, advanced manufacturing technology applications, and AI-assisted optimization. These directions aim to provide theoretical foundations and technical strategies for advanced research and practical applications of polysaccharide–protein composite hydrogels in a targeted gastrointestinal delivery system. Overall, this review underscores the significant promise of polysaccharide–protein composite hydrogels as intelligent gastrointestinal delivery platforms and provides a systematic reference for their rational design and future translational development. Full article

The performance of the cleaning system in crop harvesters directly impacts overall operational efficiency and harvest quality. Against the background of traditional design relying on physical experiments—which is costly and provides limited mechanistic insight—Discrete Element Method (DEM), Computational Fluid Dynamics (CFD), and their coupled simulation (CFD-DEM) have become key means for in-depth study of the cleaning process, capable of revealing the complex interactions between particles and between particles and airflow. With the increasingly widespread and deep application of computer simulation technology in agricultural machinery research and development, it is particularly necessary to systematically review its research progress in cleaning systems. Therefore, this study provides a comprehensive and systematic analysis and summary of the key technologies in cleaning system simulation, aiming to address the current gap in systematic reviews of simulation technology in this field. Compared with previous studies that mostly focus on a single method or a specific crop type, this paper systematically reviews the application of three simulation technologies in cleaning systems of various crop harvesters. First, based on the working principle and core operational challenges of cleaning systems, the necessity of applying simulation technology is clarified. Second, the basic principles, modeling processes, and suitable application scenarios and key points for the cleaning simulation of each method are analyzed. Third, typical cases are reviewed to summarize their key achievements in structural innovation, parameter optimization of cleaning devices, and revealing the mechanisms of material separation. Finally, current bottlenecks in simulation applications are pointed out, and future development directions are outlined, including high-precision multi-field coupling, integration with intelligent algorithms, and the construction of digital twin systems. This study aims to provide systematic theoretical reference and methodological support for the innovative design and performance improvement of cleaning systems. Full article

Laser slicing of 4H-SiC wafers offers high efficiency and minimal material loss. While nanosecond lasers are the preferred light source, simultaneously achieving high output power, excellent beam quality (M² < 1.3), and broad operational tunability remains an outstanding challenge. This study developed a highly efficient nanosecond laser source using hybrid fiber and solid-state multi-stage amplification architecture. With excellent beam quality (M² < 1.3), it achieves the highest output power, widest continuously tunable pulse width range, and broadest repetition rate range currently reported for 4H-SiC laser slicing. This advancement is poised to advance the continued development of 4H-SiC slicing technology. Full article

Conventional material balance methods, typically based on single- or dual-porosity models solvable via single-step linearization, are inadequate for hydraulically fractured shale oil reservoirs due to their pronounced heterogeneity and contrasting interzonal connectivity. Specifically, dual-zone models fail to represent the realistic characteristics of shale oil reservoirs because they treat artificially created hydraulic fractures and natural fractures as equivalent, despite their substantially different properties. To address this gap, this paper proposes a novel three-zone conceptual model, segmenting the reservoir into the matrix zone (MZ), the Weakly Stimulated Zone (WSZ, low-conductivity zone), and the Strongly Stimulated Zone (SSZ, high-conductivity zone). A corresponding three-zone gas injection replenishment material balance model is developed. This model explicitly captures interactions between injected gas and formation fluids and incorporates dynamic variations in pore volume and fluid saturation induced by imbibition. To solve the complexities introduced by the triple-porosity system, a dedicated two-step linearization solution procedure is proposed. Utilizing conventional production performance and basic PVT data, the method enables simultaneous estimation of zone-specific developed reserves and prediction of the Estimated Ultimate Recovery (EUR) through a least squares algorithm. Validation against actual well cases and multi-well statistics confirms that the method provides stable and reliable zonal reserve characterization and EUR forecasting. The results indicate that the MZ contributes the majority of the geological reserves, accounting for >70%. The WSZ contributes approximately 29.5% of the reserves and serves as the primary source for energy replenishment in the shale oil reservoir. In contrast, the SSZ contributes less than 0.5% of the reserves but acts as the dominant channel for flow convergence, controlling the main fluid production pathways. The proposed framework not only offers a practical tool for refined reserve assessment in shale oil reservoirs but also provides a computational basis and decision support for the design and injection parameter optimization of pre-pad CO₂ energy storage fracturing schemes. Full article

In response to the growing challenges of climate change and environmental degradation, the European Union announced the Green Deal on 11 December 2019, aiming for climate neutrality by 2050. To achieve this, a series of regulatory measures have been introduced to promote sustainability in the construction sector. This paper examines key EU regulations that, while not explicitly mandating wood, create conditions favorable to timber and wood-based products due to their low-carbon and renewable properties. The Carbon Removal Certification Framework (CRCF) encourages timber adoption through voluntary carbon removal incentives, whereas the new Construction Products Regulation (CPR) represents a mandatory intervention, embedding environmental and climate criteria directly into market standards. Additional regulations, including the Ecodesign for Sustainable Products Regulation (ESPR), the Energy Performance of Buildings Directive (EPBD), the Carbon Border Adjustment Mechanism (CBAM), the Nature Restoration Law (NRL), and the Regulation on Deforestation-Free Products (EUDR), further support wood by promoting resource efficiency, responsible sourcing, energy performance, and long-term carbon storage. Together, these measures form a multi-layered framework in which voluntary and binding instruments interact, indirectly supporting sustainable construction practices. Given its ability to store carbon over extended periods and achieve a net negative footprint in life cycle assessments, wood emerges as a strategic material for advancing the EU’s climate objectives. Full article