Search Results (59)

Permanent magnet synchronous motor (PMSM)-driven position servo systems in high-speed flight vehicles face severe challenges from extreme thermal environments, which induce significant parameter variations up to 25% (e.g., motor torque constant) and complex multi-scale disturbances. This paper proposes a novel adaptive robust control strategy integrating three key components: (1) an ultra-local model formulation motivated by physically consistent thermal effect analysis of electromagnetic, mechanical, and tribological parameters; (2) a dual-layer disturbance observer architecture comprising a third-order finite-time convergent extended state observer (FTCESO) for fast-varying disturbances and a σ-modification adaptive estimator for slow-varying thermal drifts; and (3) a global nonlinear integral terminal sliding mode controller with a cycloidal reaching law. Stability analysis based on homogeneous system theory and Lyapunov methods establishes practical finite-time convergence with explicit bounds. The experimental results on a TMS320F28335-based servo platform demonstrate that the proposed method reduces the maximum position deviation by 83–94% compared to PID, LADRC, and conventional SMC controllers under the tested disturbance conditions, achieving settling time reductions exceeding 90%. Under combined thermal drift and external loading, the proposed approach limits the maximum tracking error to below 0.45° while maintaining a steady-state error under 0.08°. Full article

In the era of highly integrated circuits, continuous miniaturization has significantly increased routing complexity, thereby directly impacting circuit performance. As process scaling advances and the number of on-chip metal layers increases, conventional standard cell libraries face limitations that cause severe routing bottlenecks. To overcome these limitations, this paper proposes a dual-component approach. First, we introduce a novel standard cell structure that improves routing flexibility by expanding the degrees of freedom for pin access, particularly in highly congested regions. Second, we present a physical design methodology specifically designed to ensure seamless integration with existing electronic design automation (EDA) tools, allowing new cells to be effectively placed and routed without major modifications to current flows. The proposed approach was validated using the open-source ASAP7 process design kit (PDK). Experimental results confirm significant reductions in via count and total wirelength, leading to improved routability, reduced power consumption, and enhanced performance. These findings demonstrate that combining the new cell architecture with a tailored design methodology provides a practical alternative to conventional solutions, enabling more efficient and scalable circuit designs for future technology nodes. Full article

Agricultural waste management is a strategic priority for reducing greenhouse gas emissions and transitioning to a circular bioeconomy. The thermochemical conversion of residual biomass into biochar offers a dual solution: waste recovery and the production of high-value functional materials. This narrative review summarizes the relationships among the composition of agricultural biomass, the conversion process parameters, and the structural properties of biochar, highlighting advanced modification strategies: controlled pyrolysis, physical and chemical activation, surface functionalization, and hybrid composite formation. Fundamental adsorption mechanisms, redox processes, and photocatalytic behavior are discussed, with a focus on applications in water treatment (heavy metals, dyes, emerging contaminants). The article proposes an integrative structure–property–performance framework and explores emerging concepts such as sequential use and post-use valorization of saturated biochar. Challenges related to reproducibility, industrial scaling, life cycle assessment, and carbon accounting are analyzed. Finally, a SWOT analysis is presented that highlights the potential of modified biochar as a strategic material in the circular economy. Full article

Sulfonamide antibiotics (SAs) are ubiquitous and persistent organic contaminants in aquatic and soil ecosystems due to their extensive application and high structural stability, causing rising environmental hazards. Conventional treatment approaches, generally based on physical adsorption or biological processes, remain limited in achieving efficient and stable removal as well as deep molecular modification of SAs. In recent years, modified biochar has developed as a flexible environmental functional material incorporating adsorption and reaction regulation capabilities, owing to its customizable pore structure, surface chemistry, and electronic characteristics. This study comprehensively highlights current achievements in the adsorption and degradation of sulfonamide antibiotics by modified biochar, with specific emphasis on modification techniques, structural modulation, structure–performance connections, and interfacial reaction processes. Through physical activation, heteroatom doping, defect engineering, and metal integration, biochar has developed from a traditional adsorbent into a carbon-based interfacial reactor capable of pollutant adsorption, molecular activation, and directed transformation. Surface-confined reaction interfaces, where π–π interactions, hydrogen bonding, electrostatic interactions, and metal coordination cooperatively control adsorption and transformation processes, are primarily responsible for the elimination of SAs. Moreover, the dual functions of modified biochar in driving both radical and non-radical pathways are explored, showing the vital importance of interfacial electronic structure modulation and electron-transfer mechanisms in influencing reaction efficiency and selectivity. The impact of sulfonamide molecular configurations, ambient circumstances, and concomitant chemicals on removal performance are also explored. Unlike previous reviews that mainly summarize adsorption efficiency or oxidant activation systems separately, this work integrates structural modulation, interfacial electronic regulation, and bond-selective transformation mechanisms into a unified structure–chemistry–reactivity framework. By correlating sulfonamide molecular configuration with biochar electronic structure, this review provides a mechanistic roadmap for the rational design of next-generation catalytic biochar systems. Finally, key challenges related to structural controllability, long-term stability, and engineering scalability are identified, and future research directions are proposed to support the rational design of high-performance biochar materials and the practical control of sulfonamide antibiotic pollution. Full article

The two most severe cosmological tensions in the Hubble constant $H_0$ and the matter clustering amplitude $S_8$ have the same relative discrepancy of 8.3%, which suggests that they may have a common origin. Modifications of gravity and exotic dark fields with numerous free parameters introduced in the Einstein field equations often struggle to simultaneously alleviate both tensions; thus, we need to look for a common cause within the standard $\Lambda$CDM framework. At the same time, linear perturbation analyses of matter in the expanding $\Lambda$CDM universe have always neglected the impact of comoving peculiar velocities $\mathbf{v}$ (generally thought to be a second-order effect), the same velocities that, in physical space, cannot be fully accounted for in the observed late-time universe when the cosmic distance ladder is used to determine the local value of $H_0$. We have reworked the linear density perturbation equations in the conformal Newtonian gauge (sub-horizon limit) by introducing an additional drag force per unit mass $-\Gamma \left(t\right)\mathbf{v}$ in the Euler equation with $\Gamma \equiv \gamma \left(2H\right)$, where $\gamma \ll 1$ is a positive dimensionless constant and $2H\left(t\right)$ is the time-dependent Hubble friction. We find that a damping parameter of $\gamma =0.083$ is sufficient to resolve the $S_8$ tension by suppressing the growth of structure at low redshifts, starting at $z_{★}\simeq 3.5–6.5$ to achieve $S_8\simeq 0.78–0.76$, respectively. Furthermore, we argue that the physical source causing this additional friction (a tidal field generated by nonlinear structures in the late-time universe) is also responsible for a systematic error in the local determinations of $H_0$—the inability to subtract peculiar tidal velocities along the lines of sight when determining the Hubble flow via the cosmic distance ladder. Finally, the dual action of the tidal field on the expanding background—reducing both the matter and the dark energy sources of the squared Hubble rate $H^2$, thereby holding back the cosmic acceleration $\ddot{a}$—is of fundamental importance in resolving cosmological tensions and can also substantially alleviate the density coincidence problem. Full article

Accurate core loss evaluation is essential in the design of magnetic components. Core loss is critically influenced by excitation waveform, temperature, and magnetic material; therefore, we develop a waveform equivalence coefficient, a temperature polynomial, and an electrical conductivity term to revise the Steinmetz Equation and propose a physics–data dual-driven core loss model across materials and operating conditions. The waveform equivalence coefficient achieved 100% waveform classification, and temperature polynomial modification reduced the mean square error by an order of magnitude. Using three-way analysis of variance (ANOVA), we measured the individual and synergistic impacts of the three key factors on core loss. The waveform exerts the greatest individual influence while waveform and material, as a combination, exerts the greatest synergistic influence. Given the discovery that Material 1 demonstrates a property transition point under triangular waveform, the dual-objective optimization result indicates that using Material 1 under operating conditions of 90 °C, 501,180 Hz frequency, 0.0047 T peak flux density, and a triangular excitation waveform enables the magnetic component to achieve minimum core loss with maximum transmitted magnetic energy. Full article

Pb (II) contamination in wastewater represents a grave threat to the environment and ecosystems. Consequently, there is an urgent need to prepare low-cost and highly efficient Pb (II) adsorbents. To address this need, abundant and low-cost natural silica-based desert sand (DS) was innovatively utilized as a carrier to develop efficient and selective Pb (II) adsorbents. Modified desert sand (MDS) was first prepared via 1 M HCl pretreatment for 2 h and subsequent KH550 silane modification. Pb (II)-imprinted composites (Pb (II)-IIP@MDS) were then fabricated via ion-imprinted polymerization, using Pb (II) as the template ion and N-hydroxymethacrylamide (NHMA)/hydroxyethyl methacrylate (HEMA) as dual functional monomers with a molar ratio of 1:1. The synthesized Pb (II)-IIP@MDS was comprehensively characterized by X-ray photoelectron spectrometer (XPS), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FT-IR). The adsorption capacity, selectivity, and reusability of this material for lead ions were evaluated through three experiments conducted within the optimized pH range of 6–7, with error bars indicated. In adsorption isotherm experiments, the initial Pb (II) concentration ranged from 50 to 500 mg·L⁻¹, conforming to the Langmuir model (R² = 0.992), with a theoretical maximum adsorption capacity reaching 107.44 mg·g⁻¹; this indicates that the adsorbate forms a monolayer adsorption on the homogeneous imprinted sites. Kinetics data indicate that the process best fits a quasi-first-order kinetic model (R² ≥ 0.988), while the favorable quasi-second-order kinetic fit (R² ≥ 0.982) reflects the synergistic effect of physical diffusion and ion-imprinting chemistry, reaching equilibrium within 120 min. Thermodynamic parameters (ΔH⁰ = 12.51 kJ·mol⁻¹, ΔS⁰ = 101.19 J·mol⁻¹·K⁻¹, ΔG⁰ < 0) confirmed endothermic, entropy-increasing, spontaneous adsorption. In multicomponent systems, Pb (II)-IIP@MDS showed distinct Pb (II) selectivity. It retained 80.3% adsorption efficiency after eight cycles. This work provides a promising strategy for fabricating low-cost, high-performance Pb (II) adsorbents, and Pb (II)-IIP@MDS stands as a practical candidate for the remediation of Pb (II)-contaminated wastewater. Full article

To address the technical bottleneck of the coordinated improvement of high-temperature rutting resistance, low-temperature cracking resistance and environmental protection performance of road asphalt, and to address the existing problems in the research of sepiolite modified asphalt, such as the ambiguous microscopic mechanism of action, the lack of quantitative relationship between dosage and performance, and the unclear adaptability of modification processes, this study employed high-purity sepiolite as a modifier. After optimizing its microstructure through organic and surface modification, the sepiolite with the best compatibility with asphalt was selected. Four dosage gradients of 2%, 4%, 6%, and 8% were designed. Rheological tests were conducted to investigate the effects of sepiolite on the rutting resistance at high temperature, the cracking resistance at low temperature, and the fatigue durability of asphalt. Gas chromatography–mass spectrometry (GC–MS) was used to analyze changes in the organic components of asphalt fumes, while Fourier-transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC) were applied to reveal the microscopic interaction mechanisms and smoke-suppression principles. Results show that pristine sepiolite exhibits the best compatibility with asphalt. Although modified sepiolite shows a 43–45% increase in specific surface area, the overall high–low temperature coordination of the modified asphalt decreases by 10–15%. The sepiolite dosage has a significant influence on asphalt performance: when the dosage is 4–6%, the rutting factor of asphalt increases by 25–30%, indicating the best high-temperature deformation resistance; at 4%, the asphalt creep stiffness decreases by over 15%, minimizing the low-temperature cracking risk; and at 2–4%, the fatigue life extends by 9–13%, with the most notable improvement at 2%. In terms of smoke suppression, the porous structure of sepiolite adsorbs 3–5% of the light volatile components in asphalt, while its metal oxides inhibit the release of aliphatic and aromatic hydrocarbons, reducing toxic fume emissions by 12–18%. Microscopically, the interaction between sepiolite and asphalt is dominated by physical adsorption without chemical functional group recombination. The fibrous network of sepiolite enhances the structural stability of asphalt, while the adsorption of small and medium molecular components optimizes the molecular weight distribution, achieving a dual effect of performance enhancement and smoke suppression. Full article

A common and challenging issue in drug delivery is the premature release of drugs, which prevents them from reaching the target site. Finding suitable delivery materials has become a major research focus in the medical field. Cellulose-based hydrogels are a type of material with a three-dimensional network structure and good biocompatibility, offering significant advantages for drug delivery. This review begins with the raw materials of cellulose-based hydrogels and reviews their preparation methods and principles—including physical, chemical, and other special approaches—along with chemical modification strategies and their applications in medical drug delivery, such as drug carriers, drug release wound dressings, and so on. Special emphasis is placed on modification strategies to overcome the limitations of hydrogels, such as poor pH responsiveness, self-healing ability, and temperature sensitivity. It can be achieved by modifying the chemical chain itself, adding functional fillers, and constructing a dual network. Finally, the prospects of cellulose-based hydrogels in medical applications are discussed. Cellulose-based hydrogels, as drug delivery materials, are highly effective in biomedical applications and demonstrate significant potential for clinical translation in the field of precise drug release. Full article

With the low-carbon transformation of the steel industry, using low-carbon raw materials is one of the important ways to achieve the “dual carbon” goals. Pellets have great physical and chemical properties as low-carbon furnace materials, which can significantly reduce blast furnace carbon emissions, exhibiting favorable overall environmental benefits. Increasing their proportion in the furnace is one of the important measures the steel industry can take to reduce carbon emissions. Binders play a critical role in the pelletizing process, and their properties directly influence pellet quality, thereby affecting the subsequent blast furnace smelting process. Compared with traditional bentonite, organic binders have become a potential alternative material due to their environmental friendliness, renewability, and ability to significantly reduce silica and alumina impurities in pellets while improving the iron grade. This work systematically elucidates the mechanism of organic binders, which primarily rely on the chemical adsorption of carboxyl groups and the hydrogen bonding of hydroxyl groups to enhance pellet strength, and then provides three typical examples of organic binders: lignosulfonate, carboxymethyl cellulose (CMC), and carboxymethyl starch (CMS). The common characteristic of these organic binders is that they are derived from renewable biomass through chemical modification, which is a derivative of biomass with renewable and abundant resources. However, the main problem with organic binders is that they burn and decompose at high temperatures. Current research has achieved technological breakthroughs in pellet quality by combining LD sludge, low-iron oxides, and nano-CaCO₃, including improved iron grade, reduced reduction swelling index (RSI), and enhanced preheating/roasting strength. Future studies should focus on optimizing the molecular structure of organic binders by increasing the degree of substitution of functional groups and the overall degree of polymerization. This approach aims to replace traditional bentonite while exploring applications of composite industrial solid wastes, effectively addressing the high-temperature strength loss issues in organic binders and providing strong support for the steel industry to achieve the green and low-carbon goals. Full article

Background/Objectives: Fatigue is the most common systemic manifestation of chronic liver diseases, including metabolic dysfunction-associated steatotic liver disease (MASLD). Fatigue not only adversely affects quality of life in MASLD patients but also complicates the attainment of therapeutic goals and contributes to a worse prognosis. This study aimed to analyze the relationship between clinically significant fatigue and laboratory parameters reflecting systemic inflammation, liver function, body composition, muscle strength, and blood pressure in patients with MASLD. Methods: A total of 154 patients with a confirmed diagnosis of MASLD were enrolled in this study. All participants underwent anthropometric assessment, laboratory testing, abdominal ultrasonography, and point shear-wave elastography. Muscle strength was evaluated using handgrip strength (GS) measurement and the Five Times Sit-to-Stand Test (5TSTS). Skeletal muscle mass (SMM) was quantified using dual-energy X-ray absorptiometry (DXA). Fatigue was evaluated using the Fatigue Assessment Scale (FAS), with scores ≥ 22 indicating clinically significant fatigue. Results: Patients with FAS scores ≥ 22 exhibited significantly lower hemoglobin levels (p = 0.004) and erythrocyte counts (p = 0.011), along with a significantly elevated erythrocyte sedimentation rate (ESR; p = 0.002) and C-reactive protein level (CRP; p = 0.007). Furthermore, MASLD patients with FAS scores ≥ 22 demonstrated significantly reduced relative grip strength (p = 0.012) and took longer to complete the 5TSTS (p = 0.011). Additionally, these patients had higher maximum systolic and diastolic blood pressure values compared to those with FAS scores < 22 (p = 0.028 and p = 0.019, respectively). Conclusions: These findings underscore the multifactorial nature of fatigue in MASLD and highlight the need for a comprehensive management strategy. Such a strategy should include dietary modification, increased physical activity, targeted treatment of systemic manifestations of MASLD, and appropriate management of comorbidities. Full article

A novel structure–functional-integrated particle featuring dual micromechanical interlocking property with resin matrix was constructed through surface modification of urchin-like serried hydroxyapatite (UHA) in this work, and the effect of this modification strategy on physicochemical and biological properties of dental resin composite was also investigated. A porous silica coating layer was anchored onto UHA surface via a simple template method in an oil−water biphase reaction system, and the coating time had a prominent effect on the coating thickness and morphology-structure of the particle. When these particles with different porous silica coating thickness were used as fillers for dental resin composite, results showed that UHA/PS5 (porous silica coating reaction time: 5 h) exhibited the optimal 3D urchin-like structure and a desirable porous silica coating thickness. Additionally, UHA/PS5 formed the best dual physical micromechanical interlocking structure when mixing with resin matrix, making the dental resin composites presented the desirable matrix/filler interfacial bonding, and the excellent physicochemical–biological properties, especially for flexural strength and water sorption-solubility. In vitro remineralization and cellular biological properties confirmed that the coating layer did not compromise their remineralization activity. The use of UHA/PSx provides a promising approach to develop strong, durable, and biocompatible DRCs. Full article

Bacteria and phages have coexisted for billions of years engaging in continuous evolutionary arms races that drive reciprocal adaptations and resistance mechanisms. Among the diverse antiviral strategies developed by bacteria, modification or masking phage receptors as well as their physical removal via extracellular vesicles are the first line of defense. These vesicles play a pivotal role in bacterial survival by mitigating the effects of various environmental threats, including predation by bacteriophages. The secretion of extracellular vesicles represents a highly conserved evolutionary trait observed across all domains of life. Bacterial extracellular vesicles (BEVs) are generated by a wide variety of Gram (+), Gram (−), and atypical bacteria, occurring under both natural and stress conditions, including phage infection. This review addresses the multifaceted role of BEVs in modulating bacteria–phage interactions, considering the interplay from both bacterial and phage perspectives. We focus on the dual function of BEVs as both defensive agents that inhibit phage infection and as potential facilitators that may inadvertently enhance bacterial susceptibility to phages. Furthermore, we discuss how bacteriophages can influence BEV production, affecting both the quantity and molecular composition of vesicles. Finally, we provide an overview of the ecological relevance and efficacy of BEV–phage interplay across diverse environments and microbial ecosystems. Full article

This study establishes a covalently anchored wettability alteration strategy for enhanced oil recovery (EOR) using perfluorinated siloxane (CQ), addressing limitations of conventional modifiers reliant on unstable physical adsorption. Instead, CQ forms irreversible chemical bonds with rock surfaces via Si-O-Si linkages (verified by FT-IR/EDS), imparting durable amphiphobicity with water and oil contact angles of 135° and 116°, respectively. This modification exhibits exceptional stability: increasing salinity from 2536 to 10,659 mg/L reduced angles by only 6° (water) and 4° (oil), while 70 °C aging in aqueous/oleic phases preserved amphiphobicity without reversion—supported by >300 °C thermal decomposition in TGA; confirming chemical bonding durability. Mechanistic analysis identifies dual EOR pathways: amphiphobic surfaces lower rolling angles, surface free energy (SFE), and fluid adhesion to facilitate pore migration, while CQ intrinsically reduces oil-water interfacial tension (IFT). Core displacement experiments showed that injecting 0.05 wt% CQ followed by secondary waterflooding yielded an additional 10–18% increase in oil recovery. This improvement is attributed to enhanced mobilization of residual oil, with greater EOR efficacy observed in smaller pore throats. Field trials at the Huabei Oilfield validated practical applicability: Production rates of test wells C-9 and C-17 increased several-fold, accompanied by reduced water cuts. Integrating fundamental research, laboratory experiments, and field validation, this work systematically demonstrates a wettability-alteration-based EOR method and offers important technical insights for analogous reservoir development. Full article

This study proposed a pH-driven co-precipitation strategy to overcome the limitations of traditional physical blending in functional improvement of a dual-protein system. The results demonstrated that, in comparison with the soy-pea blended protein (SPBP), the soy-pea co-precipitated protein (SPCP) showed a decrease in α-helix and β-sheet content, accompanied by in an increase in random coil structure. SPCP exhibited decreased fluorescence intensity, smaller particle size (from 392.2 to 176.1 nm) with increased absolute zeta-potential values (from −13.7 to −19.7 mV), reduced surface hydrophobicity (from 21,987.3 to 9744.8), and increased content of disulfide bonds. Structural optimization of SPCP significantly bolstered intermolecular interactions between SPI and PPI. Molecular docking simulations also validated the presence of abundant hydrophobic interactions and hydrogen bonds within in the blend system. These modifications significantly enhanced the solubility of SPCP (especially SPCP8.0). The rheological analysis further revealed that the storage modulus (G′) and loss modulus (G″) of SPCP8.0 were both higher than those of SPBP, while its tan δ was lower than that of SPBP, indicating synergistic interactions between proteins. These interactions contributed to the formation of a more stable three-dimensional network structure, thereby conferring it with superior gel properties. These findings provide theoretical foundations for improving the functional properties of plant-based dual-protein and their applications in plant-based meat production. Full article