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Pluronic F127-functionalized cerium fluoride nanocomposite: synthesis, characterization, and its enhanced antibacterial activities
The persistence of pathogenic bacteria, rising antibiotic resistance, and the ongoing need for effective anticancer agents necessitate the development of advanced multifunctional therapeutic strategies. In this study, CeF? nanoparticles and PF127-functionalized CeF? (CeF?PF127) nanocomposites were synthesized via a facile wet chemical route and systematically characterized for their structural, optical, and biological properties. XRD confirmed the formation of phase-pure hexagonal CeF? with crystallite sizes of 31nm (CeF?) and 27nm (CeF?PF127), while SAED revealed lattice fringes of approximately 0.27nm (CeF?) and 0.29nm (CeF?PF127). EDAX and XPS validated the Ce/F stoichiometry and the successful surface functionalization with PF127. Optical analyses showed a slight reduction in band gap from 3.15 to 3.09eV upon polymer coating, and PL spectra indicated enhanced defect-related emission in CeF?PF127, suggesting stabilization of Ce3? ions and oxygen vacancy sites. Biological evaluations demonstrated that CeF?PF127 exhibited superior antioxidant activity (DPPH assay) and enhanced anticancer efficacy against MG-63 osteosarcoma cells, with lower IC?? values over 2472h. Antibacterial studies against S. aureus, B. subtilis, K. pneumoniae, and S. dysenteriae revealed larger inhibition zones (1820.5mm) and improved MIC/MBC values (600/1000gmL?1) compared to bare CeF?. Biocompatibility assessment using L929 fibroblasts confirmed cell viability exceeding 80% for both samples. Collectively, these results demonstrate that CeF?PF127 is a stable, multifunctional nanocomposite with promising potential for biomedical applications. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2026. -
Banana bract derived cellulose coatings for enhancing shelf life of cherry tomatoes: Insights in to a sustainable post harvest technology
The increasing substantial generation of food waste poses a critical challenge for global waste management. A potential solution involves extracting commercially valuable products, such as biopolymers, from food waste. Cellulose biopolymer emerges as a promising candidate in this context. The current research investigates the potential of employing banana bracts (Musa acuminata) as a low-cost substrate for the extraction of cellulose biopolymer. Cellulose extraction from various residues of banana processing waste has been previously researched. However, there is a limited amount of the literature on cellulose extraction from the bracts that are left over after processing. The initial extraction phase involves an ethanol-toluene treatment to remove the laxatives, followed by an alkali treatment using KOH and bleaching using a mixture of acetic acid and sodium chlorite solution to derive white cellulose fibres. The extraction of cellulose from banana bracts yielded 36.98 0.0094% (w/w%). Examination of functional groups utilizing Fourier transform infrared provided characteristic peaks of cellulosic material. X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, and scanning electron microscopy were used to comprehend further the molecular architecture, thermal stability, and purity of the extracted cellulose. The cellulose mixture of varying concentrations (0.5, 0.75, and 1.0% [w/v%]) was coated on cherry tomatoes to investigate their shelf-life extension property. The cherry tomatoes (Solanum lycopersicum var. cerasiforme) coated with 0.75% (w/w%) cellulose solution retained firm structure and fresh appearance after 8days, in contrast with the decayed control group. The current investigation focuses on novel insights into the potential of banana bracts as a valuable resource in the pursuit of sustainable and cost-effective cellulose extraction, for both waste management and enhancing the preservation of perishable food items. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025. -
Coupling study of surface energy transmission in piezomagnetic tetrahedral laminate: a continuum mechanics analysis across a manifold substrate loaded by viscous gel
This paper examines Love-type energy transmission in a multilayered piezomagnetic tetrahedral structure (PMTS) and heterogeneous semi-space bar (HSS) structure with a viscoelastic gel (VL) on top. Energy transmission behaviour is examined in two physically important cases i.e. magnetically open (MO) and magnetically short (MS) circuit boundary. The main study focuses on the dispersion behaviour of phase velocity of a Love-type energy influenced by the combination of VL, PMTS and HSS. The dispersion relation for Love-type waves was determined analytically, and phase velocity graphs were plotted and analysed using numerical simulations using Mathematica software. A comprehensive study was conducted to acquire the effects of significant variables on phase velocity, including material heterogeneity, piezomagnetic coupling, and viscoelastic layer thickness. The research findings indicate the attenuation properties of the VL, PMTS and HSS materials in MO and MS conditions. Graphical comparisons highlight the piezomagnetic coupling caused the phase velocity curves to change consistently, demonstrating its significance in wave propagation. There was almost no difference in phase velocity between the magnetically open and short circuit scenarios, indicating that boundary constraints dont much affect how waves propagate. Phase velocity affects the PM coupling parameter. Higher material density leads to reduced phase velocity, emphasizing the role of density in influencing wave propagation. The model is confined to linear wave transmission and does not consider nonlinear influence. Moreover, the analysis is based on idealized material properties following heterogeneity. The design and advancement of energy harvesters, sensors, and wave manipulation instruments that employ PMTS with viscoelastic gel coatings can be aided by the studys conclusions. Effective usage of surface waves in these structures requires an understanding of their behaviour. This study offers a comprehensive analysis of surface wave propagation in a VL-PMTS-HSS composite structure. The comparative study of different rheological materials and the incorporation of magnetic effects contribute to the originality of the research. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025. -
Broad spectrum antibacterial activity of nanostructured Cu oxide thin films grown via glancing angle sputtering deposition
The demand for antibacterial surfaces has intensified since the recent pandemic, underscoring the need to prevent microbial adhesion on high-contact surfaces. Metallic and metal oxide nanostructures exhibit intrinsic antibacterial properties, motivating the development of scalable, cost-effective fabrication routes for functional coatings. In this study, copper oxide (CuO) thin films were deposited by magnetron sputtering and further nanostructured via glancing angle deposition (GLAD). The films exhibited pronounced antibacterial efficacy, inactivating Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) with efficiencies over 98% after 8h of exposure. Increasing the deposition angle enhanced surface roughness and hydrophobicity, which directly correlated with higher bacterial inactivation. Longer exposure further improved antibacterial performance, demonstrating time-dependent activity. These results establish GLAD-fabricated CuO thin films as a promising, industrially scalable strategy for next-generation antimicrobial surface coatings. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2026. -
Towards Optimal ?-Binding Functions of (2K1?K2)-Free Graphs and (P3?K1)-Free Graphs
A function f:N?R is called a ?-binding function for a hereditary family G of graphs, if ?(G)?f(?(G)) for every G?G where ?(G) and ?(G) denote the chromatic number and clique number respectively. In his influential work, Gya?fa? (1987) showed that the family of (2K1?K2)-free graphs and the family of (P3?K1)-free graphs are ?-bounded. Randerath and Schiermeyer (2004) improved the ?-binding functions of both these classes to x+12. In this paper, we further improve the ?-binding function of both these classes to x22 for x?3. Furthermore, we obtain a tight chromatic bound for (P3?K1)-free graphs with clique number 4. The Author(s), under exclusive licence to Springer Nature Japan KK 2025. -
Analysis using a modified Johnsoncook model for AISI 304 stainless steel and ofprior dynamic tensile behavior deformed AISI type 304 stainless steel
304 stainless austenitic steel (AISI 304) is renowned for its high temperature resistance and has been the subject of considerable research. To explore its rheological behavior at high temperature, isothermal hot compression experiments were conducted on the Gleeble-3800 thermal simulator at temperatures of 8001200 C, strain rates of 0.01111 s-1, and a total strain of 60%. From the experimental data, a JohnsonCook (JC) constitutive model was formulated and further optimized. The optimized model considers the combined effect of strain, strain rate, and temperature, resulting in a more precise constitutive equation. The enhanced JC model had excellent predictive power, with a correlation coefficient (Rco) of 0.9884 and an average absolute relative error (AARE) of 8.42%. ABAQUS simulations for verification confirmed the model to be valid. This study offers valuable theoretical information for the hot working of SS 304, enabling more precise predictions of stress behavior at high temperature and easier optimization of processing parameters and overall material behavior. Also, deformation of metastable austenitic stainless steel at temperatures below the Md point leads to the transformation of austenite into martensite. This study investigates how prior deformation, conducted at temperatures both below and above Md, affects the dynamic tensile behavior of AISI 304 stainless steel. Pre-deformation at 25C (below Md), as well as at elevated temperatures of 200C and 300C (above Md), enhances both the yield strength and ultimate tensile strength of the material. Notably, prior deformation at 25C to a small equivalent strain (< 0.03) results in significant improvements in strength (22%) and ductility (2137%) during subsequent high strain-rate tensile loading at 200 and 300s?1. The evolution of local strain fields and strain rates is analyzed using digital image correlation. Additionally, the development of localized necking is investigated through in-situ high-speed camera imaging. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025. -
Analytical investigation of heat transfer in multilayer human eye based on dual-phase-lag thermoelastic theory
Thermal damage to ocular tissues is a critical medical concern because even small temperature elevations can impair corneal endothelial function, accelerate cataract formation, and disrupt retinal metabolism. This issue is particularly relevant in regions with intense thermal environments, such as Saudi Arabia, where preventive health care and advanced biomedicalfacilities are required. This study develops a predictive framework for estimating temperature distributions within the human eye under external heat exposure. A dual-phase-lag (DPL) bioheat transfer model incorporating two thermal relaxation times is formulated to capture finite speed thermal wave propagation in the multilayer structure of the eye, and closed-form analytical solutions are obtained using a normal mode approach. A mechanics-informed machine learning surrogate model is then constructed using data generated from the analytical DPL solutions, enabling rapid prediction of intraocular temperature across the parameter space. Parametric investigations examine the effects of ambient temperature, evaporation rate, tissue porosity, and blood perfusion on the thermal response of the six ocular layers. Comparisons with the LordShulman and classical Fourier models reveal important differences in predicted temperature behavior under non-Fourier heat transfer. Additional analysesincluding thermal safety mapping, sensitivity assessment, and response surface visualizationprovide further insight into the combined influence of environmental and physiological parameters. The results show that non-Fourier thermal effects significantly influence peak intraocular temperature, while ambient temperature and evaporation dominate anterior eye heating and perfusion primarily affects deeper tissues. The present model assumes axisymmetric geometry and temperature-independent material properties, which may be extended in future studies using three-dimensional or patient-specific models. Overall, the proposed hybrid analyticalmachine learning framework provides an efficient tool for ocular thermal risk assessment and supports the development of preventive strategies for populations exposed to extreme thermal environments. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2026. -
Neural correlates of auditory comprehension and integration of sanskrit verse: a functional MRI study
In this investigation, we delve into the neural underpinnings of auditory processing of Sanskrit verse comprehension, an area not previously explored by neuroscientific research. Our study examines a diverse group of 44 bilingual individuals, including both proficient and non-proficient Sanskrit speakers, to uncover the intricate neural patterns involved in processing verses of this ancient language. Employing an integrated neuroimaging approach that combines functional connectivity-multivariate pattern analysis (fc-MVPA), voxel-based univariate analysis, seed-based connectivity analysis, and the use of sparse fMRI techniques to minimize the interference of scanner noise, we highlight the brain's adaptability and ability to integrate multiple types of information. Our findings from fc-MVPA reveal distinct connectivity patterns in proficient Sanskrit speakers, particularly involving the bilateral inferior temporal, left middle temporal, bilateral orbitofrontal, and bilateral occipital pole. Voxel-based univariate analysis showed significant activation in the right middle frontal gyrus, bilateral caudate nuclei, bilateral middle occipital gyri, left lingual gyrus, bilateral inferior parietal lobules, and bilateral inferior frontal gyri. Seed-based connectivity analysis further emphasizes the interconnected nature of the neural networks involved in language processing, demonstrating how these regions collaborate to support complex linguistic tasks. This research reveals how the brain processes the complex syntactic and semantic elements of Sanskrit verse. Findings indicate that proficient speakers effectively navigate intricate syntactic structures and semantic associations, engaging multiple brain regions in coordination. By examining the cognitive mechanisms underlying Sanskrit verse comprehension, which shares rhythmic and structural features with music and poetry, this study highlights the neural connections between language, culture, and cognition. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025. -
Efficient one-pot green synthesis of carboxymethyl cellulose/folic acid embedded ultrafine CeO2 nanocomposite and its superior multi-drug resistant antibacterial activity and anticancer activity
Due to the prevalence of drug-resistant bacteria and the ongoing shortage of novel antibiotics as well as the challenge of treating breast cancer, the therapeutic and clinical sectors are consistently seeking effective nanomedicines. The incorporation of metal oxide nanoparticles with biological macromolecules and an organic compound emerges as a promising strategy to enhance breast cancer treatment and antibacterial activity against drug-resistant bacteria in various biomedical applications. This study aims to synthesize a unique nanocomposite consisting of CeO2 embedded with folic acid and carboxymethyl cellulose (CFC NC) via a green precipitation method using Moringa oleifera. Various spectroscopic and microscopic analyses are utilized to decipher the physicochemical characteristics of CFC NC and active phytocompounds of Moringa oleifera. Antibacterial study against MRSA (Methicillin-resistant Staphylococcus aureus) demonstrated a higher activity (95.6%) for CFC NC compared to its counterparts. The impact is attributed to reactive oxygen species (ROS), which induces a strong photo-oxidative stress, leading to the destruction of bacteria. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of CFC NC are determined as 600g/mL and 1000g/mL, respectively. The anticancer activity against breast cancer cell resulted in the IC50 concentration of 10.8?g/mL and 8.2?g/mL for CeO2 and CFC NC respectively.The biocompatibility test was conducted against fibroblast cells and found 85% of the cells viable, with less toxicity. Therefore, the newly synthesized CFC NC has potential applications in healthcare and industry, enhancing human health conditions. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024. -
Clitoria ternatea flower extract assisted synthesis of Pluronic F127 and l-histidine coated SrO2 as a multimodality nanocomposite for anti-cancer, anti-oxidant, and antimicrobial activities
Hepatocellular carcinoma (HepG2) is a highly aggressive liver cancer with poor prognosis, limited treatment options, and high mortality rates, making it a serious global health concern that demands urgent development of more effective and safer therapeutic approaches. In this context, the present study focuses on the green synthesis of SrO2 nanoparticles using Clitoria ternatea flower extract, followed by surface modification with Pluronic F127 (PF127) and L-histidine (LH), to fabricate SrO2-PF127-LH nanocomposites aimed at evaluating their potential anticancer efficacy against the HepG2 cell line. Various analytical techniques were used to characterize the nanocomposite, and then their anticancer activity against HePG2 liver cancer cells, antioxidant properties, and antimicrobial activity against the bacteria mentioned above were evaluated. XRD revealed the crystalline nature of SrO2 with atetragonal phase. FTIR spectrum confirmed the SrO stretching band at 573cm?1 for SrO2-PF127-LH nanocomposite. UVvisible analysis revealed the band gap energies of 4.13eV for SrO2 and 4.07eV forSrO2PF127LH nanocomposite. The surface defects including oxygen vacancies of SrO2-PF127-LH nanocomposite were investigated using PL analysis. The SrO2PF127LH nanocomposite exhibited excellent antibacterial and antioxidant activities when compared to SrO2 nanoparticles alone. In addition, the SrO2PF127LH nanocomposite had enhanced anticancer activity against liver cancer (HePG2) cell lines. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025. -
KMSBOT: enhancing educational institutions with an AI-powered semantic search engine and graph database
In the rapidly evolving field of education, a semantic search engine is essential to efficiently retrieve knowledge experts data. Universities and colleges continuously generate a vast amount of educational and research data. A semantic search engine can assist students and staff in efficiently searching for required information in such a big data pool. The existing systems have limitations in providing personalized recommendations that align with the individual learning objectives of students and scholars, thus hindering their educational experience. To address this, this paper proposed a KMSBOT. This novel recommendation system effectively summarizes academic data and provides tailored information for students, research scholars, and faculty, enhancing educational experiences. This paper meticulously details the development of KMSBOT, which comprises a neo4j-based knowledge graph technique, the NLP method for data structuring, and the KNN machine learning model for classification. The system employs a three-module approach, utilizing data structuring, NLP processing, and semantic search engine integration. By leveraging Neo4j, NLTK, and BERT in Python, this proposed work ensures optimal performance metrics such as time, accuracy, and loss value. The proposed solution addresses traditional recommendation systems limitations and contributes to a brighter future, improving user satisfaction and engagement in academic environments. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024. -
Mechanics of SH and anti-plane SH waves in orthotropic piezoelectric quasicrystal with multiple surface effect
Significant restrictions have been found in the selection of piezoelectric materials and the direction of wave propagation in earlier studies on surface acoustic wave sensors. The primary goal of the current work is to investigate how wave propagation direction influences the performance of SAW macro- and nano-sensors in an effort to remove such barriers in the technological revolution of SAW sensors. A proposed model is established to study Shear Horizontal (SH) and anti-plane SH wave propagation in piezoelectric materials with surface effects. The theoretical forms are constructed and used to present the wavenumber of surface waves in any direction of the piezoelectric medium, based on the Extended Stroh formalism. In addition, we take into account surface elasticity theory in order to obtain the phase velocity equation based on the wavenumber expression. The model incorporates surface elasticity, piezoelectricity, and permittivity to account for nanoscale surface phenomena. Two configurations are examined: an orthotropic piezoelectric material layer over an elastic framework and a piezoelectric material half-space with a nano substrate. Analytical expressions for frequency equations are derived for both symmetric and anti-symmetric waves. Numerical results highlight the critical thickness of the piezoelectric layer, where surface energy significantly influences dispersion properties. The effects of surface elasticity and density on wave velocity are analyzed, revealing a spring force-like influence on boundaries. The research investigates SH wave transmission in anisotropic, transversely isotropic piezoelectric nanostructures. The findings could aid in designing SAW devices and piezoelectric sensors, as well as producing more effective surface acoustic wave sensors, based on recent theoretical work summaries. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2024. -
An evaluation of SH and anti-plane SH wave signals for nanosensor applications using two distinct models of piezoelectric materials lead zirconate titanate (PZT-2) and PZT-5H
Investigating how wave propagation affects the functionality of surface acoustics wave (SAW) macro- and nanosensors is the main objective of the current investigation. Consequently, the surface piezoelectricity theory is used to investigate shear horizontal waves (SH) in an orthotropic PQC layer that is layered on top of an elastic framework (Model I), a piezoelectric substrate, and an orthotropic PQC substrate (Model II). Approach: A variable-separable approach is used in the study. Based on the differential equations and matrix formulation, theoretical forms are created and utilized to display the wavenumber of surface waves in any direction of the piezoelectric medium. Two configurations are examined: an orthotropic piezoelectric material layer over an elastic framework and a piezoelectric material half-space with a nanosubstrate. Analytical expressions for frequency equations are derived for both symmetric and anti-symmetric waves. Study investigates the effects of surface elastic constants, surface density, anisotropic piezoelectric constant, and symmetric and anti-ssymmetric modes on phase velocity. The study is confined to only linear wave propagation. Additionally, the analysis is based on idealized material properties and surface properties of the material. Surface effect study is the novelty which is conducted in the piezoelectric model and their applications in sensors. The findings of this research may be useful in designing surface acoustic wave sensors (SAW) devices. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2025. -
Study of vibrations in smart materials semiconductor under differential imperfect contact mechanism and nanoscale effect with electromechanical coupling effect
The work focuses on the transference of Love-type waves which are surface seismic waves that cause horizontal displacement perpendicular to the direction of propagation, in a multiferroic solid cylindrical structure, where the interface is assumed to be imperfect and made of a magneto-electro-elastic (MEE) structure. The analytical solution for the layer is obtained using the spatially variable quasi-classical technique which approximates complicated differential equations while maintaining their key physical properties. The coefficients of waves phase velocities and attenuation are greatly affected by different parameters as shown in the numerical example. In addition, a graphical comparison of electrical, magnetic, mechanical, magneto-mechanical, electromechanical, and magneto-electrical imperfections in electrically and magnetically open and short cases is presented. The phase velocity is higher in the electrically and magnetically open case as compared to the short case as shown in the results. Some major outcomes are summarized here: the bonding parameter is highly proportional to the phase velocity and inversely proportional to the attenuation coefficient, and imperfection parameters have a serious influence on the curve of phase velocity and attenuation coefficient. This theoretical study leads to the understanding of piezoelectric and piezomagnetic coupling and its potential application and design to sensors, actuators, energy harvesters, and nano-electronics. The novelty lies in the adoption of the quasi-classical method to approach solving differential equations using a polar coordinate system for the first time. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2025. -
Dynamic stress concentrations in piezoelectric materials with semi-elliptical surface notches under shear horizontal waves
Dynamic loading causes high stress concentrations at surface notches, which are further aggravated by piezoelectric effects. This research presents a novel semi-analytical technique for studying dynamic stress concentrations in semi-elliptical surface notches in piezoelectric materials subjected to shear horizontal (SH) wave incidence. The mirror technique is employed to apply traction-free and electrically insulating boundary conditions, converting the half-space problem into its analogous full-space form. Mathieu functions and elliptical coordinate system are adopted to model the geometry of the semi-elliptical notch accurately. By separating the governing equations, the potential function is obtained, and boundary conditions are applied to construct an infinite set of linear algebraic equations. To ensure reliability of the solution, a truncation scheme based on Mathieu function convergence behavior is proposed before solving the system. Numerical simulations are performed with a thorough parametric study to reveal the effects of important parameters like the incidence angle of waves, wave frequency, notch depth, and piezoelectric material characteristics on the behavior of scattered wave fields and dynamic stress concentrations. The presented model enjoys wide geometric applicability, provides necessary theoretical guidelines for the design of piezoelectric elements and serves as a baseline for the validation of computational approximations. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2025. -
Surface wave propagation in one-dimensional layered substrate composed of hexagonal piezoelectric quasicrystals with an imperfect interface
To design and optimize piezoelectric quasicrystal (PQC) surface acoustic wave (SAW) devices, a detailed study of surface wave propagationspecifically Rayleigh and Love wavesin PQC-layered structures with weak interfaces is conducted. A hybrid LegendreLaguerre polynomial approach is developed to analytically solve the wave dynamic equations in these structures, overcoming the limitations of traditional Laguerre polynomial methods. The interplay between piezoelectric effects and weak interface characteristics is thoroughly analyzed. Notably, new phenomena are uncovered: weak interfaces in the phonon and phason fields reduce structural stiffness, whereas weak interfaces in the electric field increase it. These effects are especially prominent at frequencies exhibiting significant dispersion. Additionally, the weak interface is found to diminish the piezoelectric coupling of phonon modes in Love waves. The findings provide a strong theoretical basis for the design and optimization of PQC-based SAW devices. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2025. -
Analysis of Rayleigh-type wave energy transmission in piezoelectric substrate following GreenNaghdi type III, MooreGibsonThompson and three-phase-lag theories
This study investigates the propagation of Rayleigh-type surface waves in a homogeneous, transversely isotropic piezoelectric half-space under various boundary conditionsspecifically, stress-free, electrically open- or short-circuited, and thermally insulated or isothermal surfaces. We analyze the problem within the framework of the GreenNaghdi type III (GN-III) and three-phase-lag thermoelastic models named as model I. Also, studies carry the comparative study with Rayleigh surface wave propagation in piezoelectric media influenced by thermal effects and the presence of voids where this has analytical solutions for Rayleigh wave propagation in a nonlocal piezo-thermoelastic medium with voids, employing the MooreGibsonThompson thermoelasticity theory that incorporates memory-dependent effects named as model II. Plane harmonic wave solutions are employed to determine mechanical displacements, electric potential and temperature variations. Using these results, expressions for stress, electric displacement and temperature gradient are derived. Four secular equations corresponding to different boundary conditions are formulated for the considered half-space. The trajectories of surface particles are shown to follow elliptical paths in a vertical plane parallel to the direction of wave propagation, with the eccentricity of these ellipses explicitly calculated. When there is no phase difference between the vertical and horizontal displacement components, the particle motion degenerates into a straight-line path. A previously established analysis is recovered as a special case of the present model. The effects of various wave characteristicsincluding phase velocity, attenuation coefficient and specific lossare illustrated graphically for both the GN-III and three-phase-lag models, using cadmium selenide (a 6-mm class, hexagonally symmetric material) as the representative medium. The findings of this study highlight several distinct scenarios that enhance the understanding of Rayleigh wave propagation in complex material systems, especially those containing voids. This research offers important insights into the interplay between piezoelectric components and surface wave behavior, paving the way for advancements in sensor design, improved energy harvesting techniques and innovative seismic monitoring applications. This mathematical framework can serve as a foundation for the design and development of temperature sensors and other piezoelectric surface acoustic wave devices. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2025. -
Shear wave interaction with cylindrical magneto-electro-elastic structures
The present study develops an extended analytical framework for investigating Love-type wave propagation in multilayered magneto-electro-elastic (MEE) composites while accounting for nanoscale electrical, magnetic, and mechanical interfacial imperfections. The primary purpose is to establish a generalized dispersion relation that unifies classical Love-wave theory with coupled-field effects and imperfect interface conditions. The methodology employs the complex function approach in conjunction with the Helmholtz equation and wavefield superposition theory. Interfacial imperfection factors are introduced via a spring-type boundary model, leading to an infinite system of equations. A systematic truncation procedure ensures convergence of the analytical solution, and numerical simulations are performed to illustrate the influence of imperfections, thickness ratio, and coupling coefficients on dispersion, attenuation, and coupling efficiency. Findings reveal that imperfections significantly suppress phase velocity, with electrical defects producing stronger effects than magnetic ones, while mechanical bonding imperfections accelerate attenuation. Combined imperfections exhibit a synergistic nonlinear influence, producing dispersion shifts more severe than the sum of individual effects. Comparisons between EMO and EMS boundary conditions highlight that stress-driven EMS interfaces are more sensitive to imperfections than displacement-driven EMO boundaries. Additionally, increasing the guiding layer thickness enhances wave confinement, raising phase velocity and partially mitigating defect influence. Validation is achieved by demonstrating that the model naturally reduces to the classical Love-wave solution in the absence of coupling and imperfections, showing excellent agreement with previously published results. The novelty of the work lies in providing the first comprehensive formulation that integrates piezoelectric, piezomagnetic, and imperfection effects within a unified Love-wave framework. Limitations include restriction to anti-plane shear (SH) motion and idealized isotropic elastic half-space substrates, which may be extended in future studies to anisotropic or viscoelastic media. Practical applications include non-destructive evaluation of layered composites, defect detection, fatigue life prediction, energy harvesting, and the design of piezoelectric/piezomagnetic sensors. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2025. -
Dynamic stress analysis of semi-elliptical notches in PZT media under SH wave interaction using Mathieu functions
This work develops a rigorous analytical framework to examine the scattering behavior and dynamic stress response of semi-elliptical notches in piezoelectric half-planes subjected to anti-plane shear (SH) waves. The framework unifies the treatment of cracks, circular holes, and notches within a consistent wavedefect interaction model, while explicitly incorporating piezoelectric coupling and nanoscale surface/interface effects. The analysis employs the complex function method in combination with the Helmholtz equation and wavefield superposition theory, resulting in an infinite system of equations that rigorously enforces continuity and boundary conditions. A systematic truncation scheme is then applied to ensure stable and convergent solutions. The results reveal that surface/interface effects play a crucial role in suppressing the dynamic stress concentration factor (DSCF), particularly under vertical SH-wave excitation, while sharper resonance peaks emerge at low modulus ratios and higher piezoelectric constants, such as PZT-5H and BaTiO?. In the absence of piezoelectric coupling, the formulation seamlessly reduces to classical elasticity, ensuring strong theoretical consistency. Validation is achieved through recovery of benchmark solutions (semicircular notch and edge crack), graphical comparisons with prior results, and the rapid convergence of the truncated system, confirming the models accuracy and robustness. The findings hold significant implications for structural health monitoring, non-destructive evaluation, and the design of advanced piezoelectric composites, where accurate prediction of stress amplification and defect evolution is essential. Although the present study focuses on semi-elliptical notches in half-plane geometries under SH-wave loading, the approach can be readily extended to more general defect shapes and mixed-mode disturbances. The novelty of this work lies in capturing piezoelectric surface/interface effects within an exact analytical framework, thereby enhancing predictive capability for defect-induced stress concentrations and providing a reliable basis for the design and durability assessment of high-performance piezoelectric materials. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2025. -
Shearhorizontal wave transmission in prestressed rotating piezoelectricpiezomagnetic cylinders with imperfect interfaces: analytical modeling and parametric insights
This study develops an analytical framework to investigate shearhorizontal (SH) wave transmission in layered multiferroic cylinders composed of concentric piezoelectric (PE) and piezomagnetic (PM) materials under prestress and rotation. Both bi-layer and tri-layer configurations are examined, with the latter including a fiber-reinforced core, while the interfaces are modeled as mechanically, electrically, or magnetically imperfect using spring-type conditions. Closed-form dispersion relations are derived for electrically open/magnetically short and electrically short/magnetically open boundary cases. Numerical simulations are conducted to assess the influence of interfacial compliance, thickness ratio, rotation speed, and initial stress on phase and group velocities, as well as electromechanical coupling efficiency. The findings reveal that mechanical imperfection exerts a stronger influence on SH wave dispersion than electrical or magnetic defects, while PE/PM stiffening leads to monotonic phase velocity enhancement. Rotation and prestress are shown to significantly modify dispersion behavior, with PE layers more sensitive than PM layers. The novelty of this work lies in its unified treatment of multiferroic cylinders with simultaneous rotation, prestress, and multifield interface imperfections, bridging theoretical predictions with practical design considerations. Although the analysis assumes linear material behavior and neglects nonlinear dissipation or thermal coupling, it provides physically consistent predictions validated against limiting cases from prior literature. The results offer valuable guidelines for the design of piezoelectricpiezomagnetic devices such as SAW gyroscopes, rotation sensors, and magnetically controlled transducers, where interfacial integrity and prestress management are critical for performance optimization. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2025.