Search Results (744)

Ionic polymer–metal composites consist of an ion-conducting polymer–gel membrane sandwiched between two flexible electrodes, representing a class of soft electroactive materials capable of large deformation under low voltage. The gel membrane, swollen with solvent, facilitates ion migration under an electric field, enabling actuation. Tailoring the interfacial architecture between the electrode and the polymer–gel membrane is pivotal for advancing high-performance IPMC actuators. This study presents a comparative investigation of three core–shell nanocomposite electrodes, fabricated via in situ polymerization, for IPMC applications. Among these, the polyaniline-coated multi-walled carbon nanotube composite exhibits a deliberately designed hierarchical structure, with a specific surface area of 32.345 m²·g⁻¹ and a conductive doped polyaniline shell, as confirmed through XPS analysis. This optimized interface enables superior charge storage and transport, endowing the corresponding electrode with a specific capacitance of 40.28 mF·cm⁻² at 100 mV·s⁻¹—3.2 times greater than that of conventional silver-based electrodes—along with a reduced sheet resistance. When integrated with a Nafion ion–gel membrane, the PANI@MWCNT electrode achieves a 67% increase in force density and a larger displacement output compared to standard devices, directly correlated with its enhanced electrical and electrochemical properties. This work highlights the critical role of core–shell interfacial engineering in governing electromechanical performance at the electrode–gel interface and offers a practical design strategy for developing high-performance, cost-effective IPMC actuators for soft robotics, flexible electronics, and related applications. Full article

Bone defects have become a leading cause of disability and mortality. The pro-inflammatory state and impaired vascularization are major factors hindering bone defect repair. However, current bone regeneration materials lack the ability to regulate the osteoimmune microenvironment and promote vascularized bone regeneration. In this study, we employed clinically used fat emulsion (FE), which is intravenously administered to provide nutrition and energy for patients, to investigate the effect of immunomodulation on promoting angiogenesis and osteogenesis. Results from RT-qPCR analysis and immunofluorescence staining demonstrated that FE exhibited potent anti-inflammatory effects by reducing the expression of the pro-inflammatory marker inducible nitric oxide synthase (iNOS) and upregulating the expression of the anti-inflammatory marker transforming growth factor-beta (TGF-β). Endothelial tube formation and scratch assays demonstrated that FE promoted angiogenesis and cell migration by releasing vascular endothelial growth factor (VEGF) within the inflammatory microenvironment. Alkaline phosphatase (ALP) and alizarin red S (ARS) staining revealed that FE facilitated ALP activity and calcium nodule formation by releasing bone morphogenetic protein-2 (BMP-2) within the inflammatory microenvironment. These findings may prove promising and cost-effective for the clinical treatment of bone defects. Full article

The inherent hydrophobicity of polyolefin separators significantly impedes rapid electrolyte wetting, thereby limiting the electrochemical performance of lithium-ion batteries. Cellulose, as a hydroxyl-rich natural polymer, serves as an ideal material for enhancing the interface properties of separators. However, there is still a lack of systematic understanding regarding how the morphological structures of cellulose (such as granular, fibrous, or network-like forms) influence the coating structure and ion transport mechanisms. Here, three representative cellulose derivatives—microcrystalline cellulose (MCC), cellulose nanofibers (CNF), and bacterial cellulose (BC)—were selected to construct functionalized polypropylene (PP) composite separators through vacuum filtration. Experimental results demonstrate that all three cellulose coatings reduced contact angles from 50.8° to below 10°, significantly enhancing interfacial affinity. Systematic comparison reveals that cellulose configuration decisively influences separator performance: unlike the dense fiber entanglement networks formed by CNF and BC, the unique rigid granular packing structure of MCC maintains hydrophilicity while establishing more permeable ion transport pathways. Among these, MCC@PP exhibited optimal electrochemical performance, with the lithium-ion migration number increasing to 0.41 and a capacity retention rate of 88.04% after 100 cycles at 0.5 A/g. This study elucidates the relationship between cellulose configuration and the modification of separator performance, demonstrating that MCC represents a more efficient, robust, and cost-effective option for separator modification compared to complex fiber networks. Full article

Low Earth Orbit (LEO) mega-constellations are becoming the backbone of global communications, yet their cybersecurity remains critically under-addressed. Intrusion detection systems (IDSs) for such constellations face a unique trilemma of accuracy, efficiency, and interpretability under extreme SWaP-C (size, weight, power, and cost) constraints. We present FedLTN-CubeSat (FedLTN refers to Federated Logic Tensor Networks), a neuro-symbolic federated learning framework for intrusion detection in LEO CubeSat constellations. The framework first employs a lightweight spatio-temporal separable perception encoder to efficiently extract features from telemetry and IQ data, designed to operate within the computational budgets of resource-constrained on-board processors. These features feed into a differentiable first-order logic layer based on Logic Tensor Networks, which incorporates domain knowledge as logical axioms to guide learning and enhance interpretability. To enable collaborative learning across a constellation, FedLTN-CubeSat introduces an intra-orbit symbolic federated learning mechanism that aggregates only the logic-layer parameters via inter-satellite links, drastically reducing communication overhead while preserving data privacy. Furthermore, an orbit-adaptive predicate migration module transfers learned rules across different orbital configurations with minimal supervision, facilitating rapid deployment. We evaluate on two benchmarks: the CuCD-ID dataset (NASA NOS3 telemetry) and the STIN dataset (satellite-terrestrial integrated networks). FedLTN-CubeSat achieves 0.98 F1-score on CuCD-ID and 0.96 accuracy on STIN—significantly outperforming prior federated learning baselines (7% improvement) while incurring a minimal daily communication load per satellite. The framework also outputs interpretable decision traces grounded in logical axioms, enabling operators to understand and validate detections. Logical constraints improve detection of unseen attack variants by 25% over pure neural baselines. Full article

Agricultural biomass recycling efficiency is central to advancing the green and sustainable transition of agriculture. Drawing on panel data for 30 Chinese provinces from 2019 to 2023, this study measures recycling efficiency using a three-stage super-efficiency SBM model with undesirable output and examines its determinants with a panel Tobit model. The second-stage SFA indicates that the effects of external conditions on input slacks are input-specific. In particular, GDP is statistically significant only in the biomass-generation slack equation, whereas topographic relief and rural road network density do not show robust associations with any slack measure once controls are included. After removing the influence of environmental factors and random shocks, the overall national level of agricultural biomass recycling efficiency remains moderate. The national mean Stage 3 efficiency decreased from 0.586 in 2019 to 0.427 in 2022 and recovered to 0.543 in 2023. The five-year average was 0.510, which is close to the Stage 1 average of 0.503. Spatial analysis indicates weak global spatial autocorrelation, with only occasional local clustering. The efficiency centroid oscillated during the study period rather than following a one-way migration path, with a total displacement of 70.05 km. The determinant analysis indicates that the number of specialised agricultural machinery has the most stable positive association with recycling efficiency, while other policy, market, and human capital variables do not show robust significance in the short panel. These findings underline the need to align equipment deployment and collection systems with local terrain and transport conditions, expand machinery leasing and service provision, and strengthen capacity building in low-efficiency regions. Establishing a national information sharing and dispatch platform would facilitate cross-regional resource flows and more efficient allocation, while improving local service outlets would make participation more convenient for farmers and reduce transaction costs. Full article

Within a spatial-economics framework, this paper extends a general-equilibrium model to examine how high-speed rail (HSR) openings reduce migration costs and thereby alleviate regional factor misallocation. The model predicts that improved connectivity lowers labor mobility frictions, facilitates cross-regional reallocation of productive factors, and reduces misallocation. Using a panel of China’s prefecture-level cities from 2006 to 2016 and a difference-in-differences design, we estimate the causal effects of HSR on the misallocation of labor and capital. The results show that HSR openings significantly improve both labor and capital allocation, and the findings remain robust to a range of endogeneity checks and alternative specifications. Heterogeneity analyses indicate that the improvement is concentrated in eastern cities, while the effects are statistically insignificant in central and western regions. We also find that the reduction in misallocation occurs in both provincial capital and non-capital cities. These results imply that HSR can enhance resource-use efficiency and support sustainable regional development by reducing spatial frictions and promoting more balanced factor allocation. From a policy perspective, accelerating HSR network expansion can lower cross-regional mobility costs and enable freer flows of labor and capital, thereby improving allocative efficiency and fostering inclusive and sustainable growth. Full article

Apache Spark has gained widespread adoption for large-scale data processing. However, conventional caching methods inadequately address the dual challenges of performance bottlenecks and escalating energy consumption in data-intensive workloads. This paper introduces a sustainable computing framework that integrates Directed Acyclic Graph (DAG) dependency analysis with garbage collection (GC) behavior monitoring to optimize data placement between DRAM and non-volatile memory (NVM). The proposed Intelligent Hybrid Caching Management Framework (IHCMF) dynamically predicts data access patterns and migrates cache blocks based on cost–benefit analysis, achieving a 37.5% execution time reduction over default Spark configurations in SparkBench evaluations. By improving throughput-per-watt and projecting potential benefits from NVM’s near-zero idle power and extended hardware lifespan, IHCMF provides a scalable, cost-effective caching solution for resource-constrained edge computing environments. This work demonstrates that high-performance computing can be reconciled with environmental sustainability through intelligent memory management. Full article

The Integrated Fixed-film Activated Sludge (IFAS) partial nitritation/anammox (PN/A) process offers robust nitrogen removal, yet startup using pre-colonized carriers incurs high logistical costs. This study investigated the mechanism of inoculating a pilot-scale IFAS system with granular anammox sludge to treat anaerobic digestion supernatant. The treatment train integrated coagulation, pre-aeration, and an IFAS-PN/A unit. The granular-inoculated IFAS-PN/A unit achieved stable biofilm formation and a nitrogen removal rate of 0.36 kg N m⁻³ d⁻¹, benefiting from the effective interception of excessive organic carbon by the preceding coagulation and pre-aeration steps. Microbial analysis identified Candidatus brocadia as the dominant anammox genus, revealing a distinct migration pathway: bacteria transferred from disintegrating granules to the suspended sludge—acting as a transitional vector—before ultimately colonizing the carriers. While granular biomass diminished, anammox abundance in the biofilm increased to 12.0% by day 166. Furthermore, distinct spatial niches were observed: ammonium-oxidizing bacteria (AOB) dominated the suspended sludge, while nitrite-oxidizing bacteria (NOB) were effectively suppressed. These findings demonstrate the feasibility of granular inoculation for cost-effective IFAS startup and provide critical insights into the bacterial migration dynamics required for stable operation. Full article

Phthalates (PAEs), commonly incorporated into materials such as polyvinyl chloride (PVC) and polyvinylidene chloride (PVDC), are easily to migrate readily into the surrounding environment, which have become a matter of increasing concern. Traditional PAEs extraction methods have been prevented by long extraction times and high costs, requiring substitute to accelerate the extraction speed while reducing extraction costs. Ultrasonic-assisted extraction facilitates the release and dissolution of target compounds through the combined effects of acoustic cavitation and molecular vibration acceleration, which could be an effective means to overcome the limitations of traditional extraction methods. Herein, we have developed a four-frequency composite ultrasonic extraction technology for PAEs, with a recovery of 95.2%, approximately 38.2% higher than mode MU 20 kHz. Besides, an in-depth study on the mechanism of ultrasound-assisted extraction with sequential multi-frequency was conducted and we confirm that stepped-frequency ultrasound could achieve precise control of cavitation effects by dynamically adjusting frequency distribution, ensuring high extraction efficiency while maximally protecting the PVC matrix structure, providing a new technical path for efficient and green recovery of plasticizers. Full article

Structural symmetry is increasingly explored as a design concept in advanced materials for wastewater treatment, though its definition and practical relevance remain unclear. This review provides a critical overview of how symmetry (including crystallographic, pore-network, active-site, and architectural symmetry) affects pollutant removal. Representative material systems such as adsorbents, catalysts, and mixed-matrix membranes are examined for the removal of typical pollutants, including dyes, heavy metals, pharmaceuticals, and emerging contaminants. Symmetry is linked to improved transport uniformity, enhanced charge-carrier migration, facet-dependent reactivity in catalysts, and increased stability during cyclic operation. Symmetric architectures are compared with asymmetric and defect-rich designs, highlighting cases where asymmetry outperforms, particularly in complex matrices dominated by surface chemistry or kinetic accessibility. Performance metrics are discussed in their experimental contexts, with emphasis on qualitative structure–performance relationships. Environmental and economic implications are addressed qualitatively, focusing on life-cycle considerations, cost trends, scalability, and industrial feasibility rather than comprehensive techno-economic analyses. This review highlights when symmetry is beneficial, when its influence is limited, and how combining symmetry with asymmetry or defect engineering can lead to more practical wastewater treatment solutions. Full article

Reverse electrodialysis (RED) is a power generation method that harnesses the energy of mixing high- and low-salinity solutions through ion migration across ion-exchange membranes. While it is being extensively investigated as an environmentally friendly technology that utilizes renewable materials and generates no air pollution, it also has severe limitations that put RED’s technical and economic feasibility into question. This paper discusses RED’s geographical, technical, and economic limitations and provides a critical review of the attempts at addressing them. We conclude that the pretreatment costs and the capital investment costs are prohibitively expensive, making RED uneconomical compared to other renewable energy generation methods. Full article

Our Fairytales: The Cost of Migration, National Myth, and Creative Labor in Unser Deutschlandmärchen is a performance analysis that examines lived cultural narratives through the lens of the Maxim Gorki Theatre’s production of Dinçer Güçyeter’s autobiographical novel Unser Deutschlandmärchen. The impact on Turkish migrants in Germany and their descendants is explored through an investigation of primary production texts, migration and diaspora literature, and Turkish–German cultural commentary. A discussion of fairy tales and national mythos reveals the material contributions migrant communities often make to host nations through systemic endurance and cultural enrichment, frequently at the cost of forgoing “happily ever after.” The reformation of the traditional fairy tale recasts Turkish–German migrants as modern fairy-tale heroes who generate counter-cultural narratives through collective, intergenerational, and ethnographically inherited memory. Full article

This study investigated the effects of calcium carbide slag (CCS) (0–12 wt%) incorporation on the workability, electrochemical properties, durability, and microstructure evolution of sulfoaluminate cement (SAC) mortar. Results showed that increasing CCS content reduced mortar fluidity and shortened setting time, indicating that CCS accelerates early hydration. A 9% CCS content was determined to be the optimal dosage; at 28 days, compared to the control group, this dosage group exhibited a 6.53% increase in compressive strength, a 22.47% decrease in drying shrinkage, and a 0.279% decrease in mass loss. These performance improvements stemmed from CCS’s ability to inhibit pore connectivity and limit moisture migration. Electrochemical analysis further revealed that the 9% CCS dosage group had the highest charge transfer resistance and resistivity (30.00% higher than the control group), reflecting a denser matrix and greater ion transport resistance. Consequently, chloride ion permeability was significantly reduced, with electrical flux and diffusion coefficient decreasing by 39.98% and 28.89%, respectively. Microstructural observations confirmed that CCS promotes the formation and densification of hydration products, effectively improving the internal pore structure. While 9% CCS can serve as an effective functional supplementary material, its long-term durability and sustainability still face practical application challenges. Future research should focus on establishing predictive models for chloride ion permeation lifetime and conducting quantitative sustainability assessments of CCS-SAC composites, particularly evaluating material cost, energy consumption, and carbon dioxide emissions. Full article

Natural fractures are critical controls on shale oil storage and migration in the Upper Triassic Chang 7 Member of the Ordos Basin. However, conventional identification techniques—such as mud-invasion correction, R/S rescaled range analysis, and radioactive element analysis—are time-consuming, computationally intensive, and highly dependent on specialized logging data, limiting their large-scale application. To overcome these challenges, this study develops a multi-modal deep neural network that integrates conventional well logs with borehole imaging data. A coupled convolutional neural network (CNN) and deep neural network (DNN) architecture was constructed to predict fracture occurrence, dip angle, and aperture. The model achieves dip-angle prediction accuracies of 98.82% for both training and testing datasets, while aperture prediction accuracies reach 95.97% and 95.91%, respectively. Predicted dip angles are concentrated between 65° and 80°, deviating by less than 0.48° from measured values, whereas apertures fall mainly within 0.5–4.5 cm, with deviations below 0.21 cm except in extreme cases. The CNN branch effectively extracts spatial features from imaging logs, while the DNN branch captures nonlinear relationships in conventional logs. The integrated framework substantially improves fracture characterization accuracy and efficiency. This study provides a scalable and cost-effective approach for rapid fracture identification based on conventional logging data, reducing reliance on specialized imaging logs and supporting integrated geological and engineering evaluations in shale oil reservoirs. Full article

Tight oil reservoirs are widely recognized as a critical successor in global unconventional energy development and are generally characterized by distinct geological features, including fine pore throats, pronounced heterogeneity, and a high concentration of clay minerals (e.g., montmorillonite and mixed-layer illite/smectite). Severe hydration, swelling, and fines migration are readily induced during water injection or conventional water-based fluid operations, thereby resulting in irreversible impairment of reservoir permeability. Despite the excellent injectivity and capacity for viscosity reduction associated with CO₂ flooding, sweep efficiency is severely compromised by viscous fingering and gas channeling, which are induced by the inherent low viscosity of the gas. While CO₂ foam technology is widely acknowledged as a pivotal solution for addressing mobility control challenges, its implementation is hindered by a primary technical bottleneck: the incompatibility between traditional water-based foam systems and strongly water-sensitive reservoirs. A dual challenge comprising water injectivity constraints and gas channeling is presented by strongly water-sensitive tight oil reservoirs. To address these impediments, three emerging low-damage CO₂ foam systems are critically evaluated in this review. First, the synergistic mechanisms of novel quaternary ammonium salts and polymers in inhibiting clay hydration and enhancing foam stability within modified water-based systems are elucidated. Next, the physical isolation strategy of substituting the water phase with a non-aqueous phase (oil/organic solvent) in organic emulsion systems is analyzed, highlighting advantages in wettability alteration and the mitigation of water blocking. Finally, the prospect of waterless operations using CO₂-soluble foam systems—wherein supercritical CO₂ is utilized as a surfactant carrier to generate foam or viscosify fluids via in situ formation water—is discussed. It is revealed by comparative analysis that: (1) Modified water-based systems are identified as the most economically viable option for reservoirs with moderate water sensitivity, wherein cationic stabilizers are utilized to inhibit hydration; (2) Superior wettability alteration and the elimination of aqueous phase damage are provided by organic emulsion systems, rendering them ideal for ultra-sensitive, high-value reservoirs, despite higher solvent costs; (3) CO₂-soluble systems are recognized as the future direction for “waterless” flooding, specifically tailored for ultra-tight formations (<0.1 mD) where injectivity is critical. Current challenges, such as surfactant solubility, high-temperature stability, and cost control, are identified through a comparative analysis of these three systems with respect to structure-activity relationships, rheological properties, damage control capabilities, and economic feasibility. What is more, an outlook is provided on the molecular design of future environmentally sustainable, cost-effective CO₂-philic materials and smart injection strategies. Consequently, theoretical foundations and technical support are established for the efficient exploitation of strongly water-sensitive tight oil reservoirs. By bridging the gap between reservoir damage control and mobility enhancement, this study identifies viable strategies for enhanced oil recovery. Crucially, it supports carbon neutrality and sustainable energy targets via CCUS integration. Full article