Search Results (3,529)

We suggest Josephson interferometry as a quantitative probe of spin–orbit-driven phenomena in superconducting heterostructures. Two distinct mechanisms are analyzed: (i) intrinsic helical superconductivity, producing asymmetric Fraunhofer patterns with lobe deformations and field-reversal asymmetry, and (ii) emergent interfacial magnetism in ferromagnet–superconductor hybrids, where Rashba spin–orbit coupling generates spontaneous fields that rigidly shift the interference fringes. The predicted signatures—flux-shifted interference minima, anisotropic critical current suppression, and angle-dependent pattern distortions—provide direct experimental access to finite-momentum pairing and interface-localized fields via standard Josephson current measurements. Full article

Functional nanocomposites have emerged as a transformative class of materials for advanced energy and electronic applications due to their ability to integrate multiple functionalities within engineered nanoscale architectures. This review provides a comprehensive analysis of the fundamental principles governing nanocomposite behavior, including classification frameworks, commonly employed nanofillers, and critical structure–property relationships. Emphasis is placed on interfacial interactions, dispersion quality, percolation phenomena, and anisotropic effects that dictate electrical, thermal, mechanical, and electrochemical performance. State-of-the-art synthesis and fabrication strategies—ranging from solution-based and melt-processing techniques to vapor-phase deposition and additive manufacturing—are systematically examined in relation to microstructural control and scalability. The multifunctional properties of nanocomposites are critically evaluated, highlighting their relevance in energy storage systems, energy conversion technologies, flexible electronics, sensors, and electromagnetic interference shielding. Key challenges, including nanofiller agglomeration, interfacial compatibility, long-term stability, cost, and sustainability considerations, are discussed alongside emerging solutions. Finally, future perspectives focusing on next-generation nanofillers, AI-assisted materials design, and sustainable manufacturing pathways are outlined, providing a roadmap for the rational development and industrial translation of high-performance multifunctional nanocomposites. The scope of this review is deliberately focused on materials-level structure–process–property relationships in functional nanocomposites, rather than on detailed device-level electronic design or application-specific electromechanical implementations. Full article

In this paper, a new class of special polynomials, called the Sheffer-type general-$\lambda$-matrix polynomials, is introduced within the framework of the monomiality principle. This family is obtained by combining the structure of Sheffer sequences with the theory of general-$\lambda$ matrix polynomials, which leads to a unified formulation encompassing several polynomial families. Fundamental properties of the proposed polynomials are established, including their generating function, explicit series representation, summation formulas, quasi-monomial structure, differential relations, and determinant representation. The proposed framework addresses an important problem in the theory of special functions: the systematic construction of matrix-valued polynomial families that simultaneously generalize both classical scalar polynomials and existing matrix polynomial hierarchies. Such a unified structure is of broad significance, with applications in quantum mechanics (wave function expansions), mathematical physics (matrix differential equations and spectral problems), approximation theory, and the study of special functions in the matrix domain. Several hybrid forms of the proposed family are derived through appropriate choices of the defining functions, which yield polynomial subclasses related to classical families such as Hermite, Laguerre, Bessel, and Poisson–Charlier polynomials. These subclasses illustrate how the proposed framework provides a systematic approach for constructing and studying generalized polynomial structures. In each case, the matrix parameter L introduces a new layer of structural richness not present in the scalar setting, enabling the modelling of phenomena governed by matrix-valued spectral data. Furthermore, a numerical and graphical investigation of selected hybrid forms is carried out using Mathematica(version 14.3, 2025; Wolfram Research, Inc.). Surface plots, distributions of complex zeros, and real-zero patterns are presented for different parameter values, highlighting the influence of the parameters on the behavior and structural characteristics of the polynomials. Full article

Antioxidant biopolymeric films (ABFs) have emerged as promising bio-based and biodegradable polymer materials for sustainable food packaging, combining environmental sustainability with functional performance. This study identifies convergent design principles governing ABFs through a systematic mapping of research published between 2015 and 2025, organized into thematic discussions covering global trends, material strategies, processing technologies, and structure–property relationships. The analysis reveals a clear transition from biodegradable substitution materials toward performance-driven polymer systems engineered to modulate mass transport phenomena. Polysaccharide- and protein-based matrices dominate current developments due to their chemical functionality and compatibility with natural bioactive compounds; however, their inherent hydrophilicity introduces trade-offs between barrier resistance and controlled release. Recent advances increasingly employ blends, composites, and multilayer architectures to decouple mechanical stability from antioxidant migration. Processing technologies, including casting, extrusion, and multilayer assembly, are shown to play a decisive role in defining diffusion pathways and release kinetics. The findings demonstrate that the effectiveness of ABFs depends primarily on polymer–bioactive interactions and structure–property relationships rather than additive concentration alone. Future progress toward industrial implementation requires scalable fabrication strategies and predictive processing–structure–performance frameworks aligned with circular economy principles. This perspective positions ABFs as functional bio-based polymer systems capable of synchronizing antioxidant release with food oxidation kinetics, contributing to sustainable food packaging solutions. Full article

This paper presents an analysis of the impact of sub-cycle voltage reductions (below 1 ms) on the operation of a slip-ring induction motor. Due to the specific design of the slip-ring induction motor and the presence of a separate rotor circuit, direct measurements of rotor currents and voltages are possible, enabling a more detailed analysis of the physical phenomena occurring in the machine. A series of experiments was conducted using the Profline 2100 device, which enables the generation of controlled sub-cycle voltage reductions. This made it possible to directly assess the influence of such disturbances on motor operation, particularly changes in stator and rotor currents, rotational speed, and electromagnetic torque pulsations. The electrical and mechanical parameters of the motor were also identified. The obtained data were used to develop a mathematical model and implement it in the MATLAB/Simulink environment, enabling qualitative reproduction of the observed phenomena. The main novelty of this work is the analysis of the electromagnetic response of a slip-ring induction motor to sub-cycle voltage reductions below 1 ms, supported by direct measurements in the rotor circuit. The resulting model, validated against measurement results, shows qualitative agreement with the experiments and enables a more detailed analysis of motor dynamics during sub-cycle voltage reductions, including phenomena that are difficult to capture experimentally. Full article

During the production, storage, and use of solid rocket motors, the impact generated by unexpected accidents, such as collision or drop, will cause damage to the propellant and affect the safety of the motor. However, the progressive evolution mechanism of mesoscopic damage in NEPE propellant under such impact conditions has not been fully elucidated, and there is still a lack of quantitative method to evaluate the impact-induced damage degree, which restricts the engineering safety assessment of solid rocket motors. To investigate the influence mechanism, the mesoscale damage characteristics of NEPE propellant under drop-weight impact is systematically studied. First, damaged NEPE specimens are obtained by conducting drop-weight experiments with a 10 kg hammer, where the drop height is varied to apply different impact impulses. The internal meso-structure of the propellant is then characterized using micro-CT, yielding detailed imagery of the refined meso-structural features and damage morphologies in the NEPE propellant. To capture the dynamic evolution process of mesoscale damage, a mesoscopic model incorporating AP, Al, HMX particles and voids, is subsequently constructed based on the high-precision mesoscopic morphology characterized by micro-CT. By integrating the deviatoric constitutive model, Gurson plastic damage model, and bilinear cohesive zone model, high-fidelity numerical simulations of the drop-weight impact damage process are performed using the advanced SPH-FEM coupling algorithm. The results indicate that no significant damage occurs when the impact impulse is less than 13.85 N·s. As the impulse increases, phenomena including matrix microcracks, void collapse, particle/matrix interface debonding, and main crack formation appear sequentially. When the impulse exceeds 24.25 N·s, particle fragmentation and transgranular fracture occur, accompanied by plastic flow and frictional heating that induce ignition. Finally, the overall damage degree is fitted by the Boltzmann function, and a function for quantitatively describing the damage degree is obtained, which can provide theoretical support for the impact safety assessment of solid rocket motors. Full article

Contact–impact phenomena caused by joint clearances can significantly alter the dynamic response of high-speed mechanical systems, yet fewer studies combine analytical impact-force modeling, virtual prototyping, and experimental observations for multi-cylinder internal combustion engine mechanisms within a unified framework. This problem is scientifically important because the piston–connecting rod–crankshaft chain is subjected to rapid motion reversals, high transmitted loads, and local clearances that may generate shocks, force amplification, and vibration growth. The objective of this study is to evaluate the influence of mechanical impact on the dynamic response of a three-cylinder inline engine mechanism by combining analytical modeling, MSC Adams virtual prototyping, and experimental investigation. The mechanism was analyzed in two operating conditions: under load, using an experimentally derived gas pressure input, and without load at low speed imposed on the crankshaft, using a sectioned engine test bench. The loaded virtual model was studied at a crankshaft speed of 6000 rpm, with cylinder gas pressure peaks above 90 bar and engine torque oscillating around 170 Nm. A radial clearance of 0.03 mm was introduced in the connecting rod–piston joint to evaluate clearance-induced impacts. The results showed that the damping coefficient strongly influences the amplitude and harmonic content of the impact force. For the analyzed no-load case at low speed, the simulated impact force reached a maximum value of 3000 N. Experimentally, the worn connecting rod with 0.03 mm clearance exhibited markedly higher dynamic response than the clearance-free case, with the maximum longitudinal acceleration increasing from 17.77 to 48.26 m/s² at 1.341 Hz. The novelty of the study lies in the integrated analytical–virtual–experimental investigation of clearance-induced impact in a three-cylinder inline engine mechanism and in the comparative evaluation of its effects on joint forces and vibration signatures. In addition, compared to other models, the novelty lies in introducing and adapting the impact force damping component for mechanisms with rapid motion and high dynamic loads. Full article

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

Polymer–metal hybrid composites (PMHCs) represent an emerging class of materials that combine the lightweight processability of polymers with the structural and functional advantages of metals. Recent advances in material design and manufacturing have shifted attention from traditional particulate or fibrous reinforcement toward metallic architectures—continuous, architected, or topologically optimized metallic networks intentionally embedded within polymer matrices. These metallic architectures play a key role in defining the composite’s global performance, influencing stiffness, energy absorption, failure mechanisms, and multifunctional properties such as electrical or thermal conductivity. This review examines how the geometry, connectivity, and topology of metallic reinforcements govern mechanical behavior and functional responses in PMHCs. Emphasis is placed on the interplay between architecture and interface design, including surface modification strategies and mechanical interlocking phenomena. Furthermore, the paper discusses the contribution of additive manufacturing technologies in enabling complex metallic architectures and hybrid processing routes. By integrating structural, interfacial, and manufacturing perspectives, this review develops a coherent framework for understanding how metallic architecture drives the evolution of PMHCs toward multifunctional and design-driven engineering applications. The analysis of the literature consistently indicates that architectural configuration—rather than material selection alone—represents the primary factor governing multifunctional performance. Full article

Understanding the unsteady aerodynamic behavior of quadrotor unmanned aerial vehicle (UAV) is critical for improving flight stability, control, and performance, particularly in complex operational environments. In closely spaced multirotor configurations, coherent tip vortices shed from each blade convect downstream and form helical vortex streets that interact with subsequent blades and neighboring rotors. These interactions induce rapid fluctuations in local inflow velocity and effective angle of attack, resulting in transient lift variations, increased vibratory loads, and elevated acoustic emissions. This study presents a comprehensive computational investigation of quadrotor rotor interactions and wake dynamics using a large-eddy simulation (LES). Detailed analyses reveal that the formation and evolution of tip vortices and blade–vortex interaction phenomena significantly influence lift fluctuations and aerodynamic loading. The simulations capture transient wake structures and their effects on neighboring rotors, highlighting unsteady aerodynamic mechanisms that are not adequately predicted by conventional RANS or URANS approaches. Parametric studies examining vortex-street offset distance demonstrate the sensitivity of wake-induced instabilities to design and operational parameters. The results provide new physical insights into multirotor wake dynamics and establish the LES as a predictive framework for quantifying unsteady aerodynamic loading in quadrotor drones. The findings provide insights into the complex flow physics of multirotor systems, offering guidance for more accurate modeling, rotorcraft design optimization, and the development of control strategies that mitigate adverse unsteady aerodynamic effects. This study provides new insights into rotor–vortex-street interactions, with applications to multirotor UAVs, by isolating multi-vortex coupling effects and quantifying the influence of horizontal vortex spacing on unsteady aerodynamic loading, complementing existing high-fidelity LES research. Full article

Amorphous metallic materials have emerged as a promising class of functional materials for energy storage and conversion owing to their disordered atomic structure and unique interfacial properties. This review focuses on amorphous metals and alloys, including metallic glasses and high-entropy amorphous systems, with particular emphasis on their surface- and interface-driven behavior in electrochemical environments. This review analyzes how structural disorder influences key properties such as electronic structure, ion transport, catalytic activity, and mechanical compliance and how these factors govern performance in batteries, supercapacitors, electrolyzers, and fuel cells. Special attention is given to interfacial phenomena, including charge-transfer kinetics, corrosion and passivation processes, and structural evolution during long-term operation. In addition, recent advances in fabrication strategies such as rapid solidification, thin-film deposition, mechanical alloying, thermoplastic forming, and electrodeposition are discussed in relation to their ability to tailor amorphous structures and interfaces. This review also highlights critical failure mechanisms and discusses some strategies to mitigate these effects. Overall, this work provides a focused perspective on the role of amorphous metallic surfaces and interfaces in electrochemical systems, identifying current challenges in scalability, durability, and compositional control, and outlining future directions for their integration into next-generation energy technologies. Full article

Titanium dental implants are widely regarded as the gold standard for the rehabilitation of missing teeth due to their high survival rates and favorable mechanical properties. However, in the oral environment, implant materials are continuously exposed to complex chemical, mechanical, and biological factors that may lead to surface degradation, including corrosion, tribocorrosion, and mechanical wear. These processes can alter implant surface characteristics and influence biological responses in peri-implant tissues. Zirconia implants have been introduced as alternative material due to their favorable aesthetics and biocompatibility. Nevertheless, zirconia ceramics are also susceptible to degradation phenomena, including hydrothermal aging, phase transformation, and surface wear under specific conditions, although their clinical relevance remains unclear. In addition, emerging hybrid titanium–zirconia implant systems introduce new considerations regarding surface stability. This scoping review, conducted in accordance with PRISMA-ScR guidelines, summarizes the current evidence on degradation mechanisms affecting titanium, zirconia, and hybrid dental implants, with particular focus on processes occurring in the oral environment and their biological and clinical implications. The available evidence differs substantially between the two materials. While titanium degradation is well documented and supported by both experimental and clinical studies, the evidence for a hybrid implant remains limited and is largely based on in vitro and mechanistic data. Full article

The use of Bohmian mechanics as a practical tool for modeling non-relativistic quantum phenomena of matter provides clear evidence of its success, not only as a way to interpret the foundations of quantum mechanics, but also as a computational framework. In the literature, it is frequently argued that such a realistic view—based on deterministic trajectories—cannot account for phenomena involving the “creation” and “annihilation” of photons. In this paper, by revisiting and rehabilitating earlier proposals, we show how quantum optics can be modeled using Bohmian trajectories for electrons in physical space, together with well-defined electromagnetic fields evolving in time. By paying special attention to an experimental scenario demonstrating partition noise for photons, and to how the Born rule emerges in this context, the paper pursues two main goals. First, it validates the use of this simple Bohmian framework for pedagogical and computational purposes in understanding and visualizing quantum electrodynamics phenomena. Second, given that measurements are ultimately indicated on matter pointers, it clarifies what it means to measure photon or electromagnetic-field properties, even when they are considered non-ontic elements. Full article

Background/Objectives: Bloodstain pattern analysis (BPA) is widely used in crime scene investigation (CSI), yet its practical application, evidential limits, and interpretive role are often discussed in fragmented or technique-focused terms. This systematic literature review examines how BPA is used in CSI, with emphasis on its operational functions, interpretive scope, and scientific robustness. Methods: The review followed PRISMA 2020 guidelines. A comprehensive search was conducted in Scopus using predefined Boolean strings. After screening, eligibility assessment, and manual review, 18 peer-reviewed research articles published between 1996 and 2026 were included. Data were extracted systematically and analysed using thematic synthesis. Results: The findings show that BPA is applied in CSI as an integrated evidential pathway rather than as a single analytical procedure. Its uses include bloodstain detection and documentation, geometric reconstruction through trajectory and area-of-origin analysis, differentiation of mechanisms and sources to prevent misclassification, activity-level inference based on transfer and contact phenomena, and temporal reasoning related to trace formation. The review also highlights the role of validation infrastructures, including blood substitutes, animal analogues, and computational methods, which support training, experimentation, and reproducibility under ethical and practical constraints. Across the literature, reconstruction accuracy is shown to be sensitive to documentation quality, measurement assumptions, environmental conditions, and contextual limitations. Conclusions: Overall, BPA contributes to CSI by enabling structured, context-aware interpretation of blood evidence while remaining subject to measurement assumptions, contextual influences, and cognitive factors that may affect reconstruction outcomes. Its evidential value lies not only in reconstructing events, but also in supporting transparent, testable, and defensible forensic reasoning. Full article

Dielectric and magnetic spherical hollow shells are employed in many applications as standard building units. These structures are commonly subjected to size reduction to obtain a high surface area/volume ratio, a property that is in favor of specific applications. However, the size reduction enhances the importance of physical mechanisms that originate from surfaces, such as the depolarization effect. Here we tackle the problem of dielectric and magnetic spherical hollow shells, consisting of a linear, homogeneous and isotropic parent material, subjected to an external potential, $U_{ext}(\mathit{r})$, of any spatial form (either dc (static) or ac of low-frequency (quasistatic limit)). By applying the method-of-linear-recursive-solution (MLRS) to the Laplace equation, we calculate analytically the internal, $U_{int}(\mathit{r})$, and total, $U_{tot}(\mathit{r})$, potentials in respect to the external one, $U_{ext}(\mathit{r})$. From $U_{int}(\mathit{r})$ and $U_{tot}(\mathit{r})$ we calculate all relevant scalar and vector physical entities of interest. The MLRS unveils straightforwardly the existence of two distinct depolarization factors, $N_l=l/(2l+1)$ and $N_{l+1}=(l+1)/(2l+1)$, both depending on the degree, $l$, however not on the order, $\mathrm{m}$, of the mode of the external potential, $U_{ext}^{(l,m)}(\mathit{r})$. These depolarization factors, $N_l$ and $N_{l+1}$, originate from the outer, $r=\mathrm{b}$, and inner, $r=\mathrm{a}$, surfaces and are accompanied by two extrinsic susceptibilities, ${\chi }_{e,l}^{ext}={\chi }_e/(1+N_l{\chi }_e)$ and ${\chi }_{e,l+1}^{ext}={\chi }_e/(1+N_{l+1}{\chi }_e)$, respectively. Importantly, $N_l+N_{l+1}=1$, irrespective of the degree, $l$, as it should. The properties of spherical hollow shells are investigated through analytical modeling and detailed simulations, with emphasis on application-relevant scenarios including resonance phenomena in scattering, quantitative materials characterization, and shielding/distortion. The generic MLRS strategy provides a flexible and reliable route for analyzing depolarization processes in other dielectric and magnetic building-unit geometries encountered in practice. Full article