The European Physical Journal Plus最新文献

{"title":"Comparative study on structural, electronic and optical properties of metal oxide nanoparticles: computational and experimental approach","authors":"Vinayakprasanna N. Hegde","doi":"10.1140/epjp/s13360-025-06920-x","DOIUrl":"10.1140/epjp/s13360-025-06920-x","url":null,"abstract":"<div><p>The optically active gallium oxide (Ga₂O₃), magnesium oxide (MgO), nickel oxide (NiO) and zinc oxide (ZnO) nanoparticles were synthesized by green combustion method. The structural, morphological, optical and luminescence properties of prepared nanoparticles were analyzed. The first-principle calculations were performed to understand the electronic and optical properties. X-ray diffraction study confirms the polycrystalline nature and phase purity. Combustion-driven nanomaterials exhibit agglomerated, non-uniform and porous morphology. UV–visible (UV–Vis) spectroscopy was employed to explore linear and nonlinear optical (NLO) properties. The considered nanomaterials exhibit a strong response in the UV region and a wide bandgap (2–4.5 eV). The optical constants such as linear and nonlinear refractive index, optical and electrical conductivity, third-order nonlinear optical susceptibility were determined. The photoluminescence (PL) spectra reveal distinct emission peaks for each nanomaterial. Also, chromaticity and lifetime of PL emissions were discussed.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamical and optical behavior of a loop quantum gravity black holes in de Sitter spacetime","authors":"M. Umair Shahzad,&nbsp;Nazek Alessa,&nbsp;Aqsa Mehmood,&nbsp;Abdul Wahab","doi":"10.1140/epjp/s13360-025-06874-0","DOIUrl":"10.1140/epjp/s13360-025-06874-0","url":null,"abstract":"<div><p>Understanding the properties of the light ring in rotating black holes (BHs) and the equatorial timelike circular orbits in non-rotating BHs is made possible by the study of topology. This work aims to identify the zero points corresponding to various orbital configurations of circular orbits within the temporal dimension that are distinguished by the distinct topology in loop quantum gravity (LQG) BH in de Sitter (dS) spacetime. We created a vector in the <i>r</i> - <span>(theta)</span> plane using the effective potential, and the zero points of <span>(phi)</span> which represent the locations of the timelike circular orbits. We determine the topology connected to the timelike circular orbits because of this special characteristic. Simple, connected horizons are represented by zeros of winding number, whereas more complex topologies, like multi-sheeted horizons, are represented by winding numbers that are nonzero. Moreover, we also find the shadow, optical appearance, and interpretation of intensity under the influence of different parameters involving in LQGBH in dS spacetime and compare theoretical depiction of BH shadow diameter with real images of M87* and SgrA*.\u0000</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exact soliton solutions and their classifications for the generalized (2+1)-dimensional Hirota–Maccari equation using the direct integral method","authors":"Hui Wang","doi":"10.1140/epjp/s13360-025-06931-8","DOIUrl":"10.1140/epjp/s13360-025-06931-8","url":null,"abstract":"<div><p>This study addresses the generalized (2+1)-dimensional Hirota–Maccari system, a fundamental model governing bidirectional wave-mean flow interactions in nonlinear optics, hydrodynamics, and plasma physics. Existing solution methods suffer from structural incompleteness and parameter sensitivity. We systematically derive all exact traveling wave solutions using the direct integral method integrated with the complete discrimination system for polynomials, eliminating preset functional assumptions. Under the essential parameter constraint, 18 distinct solution families are rigorously classified via discriminant criteria, including rational, hyperbolic, trigonometric, and doubly periodic Jacobi elliptic function solutions. Graphical simulations validate dynamical behaviors across criticality, pattern formation, and coherence. This framework provides a universal, parameter-classified tool for modeling femtosecond optical solitons, plasma waves, and hydrodynamic extremes, with direct experimental verifiability through amplitude–velocity correlations.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Defect modulation and electric field effects on NO2 and NO adsorption on monolayer PdSe2: a first-principles study","authors":"Mingyang Gao,&nbsp;Zhi Zhao,&nbsp;Yu Xie,&nbsp;Jie Zhou,&nbsp;Na Wang,&nbsp;Peng Sun,&nbsp;Tingting Song","doi":"10.1140/epjp/s13360-025-06893-x","DOIUrl":"10.1140/epjp/s13360-025-06893-x","url":null,"abstract":"<div><p>The development of efficient and tunable hazardous gas adsorption materials can effectively mitigate the severe threats posed by toxic gases to human health. Based on density functional theory (DFT) calculations, we systematically investigate the adsorption characteristics of NO₂ and NO molecules on monolayer PdSe₂ and further explore the effects of Se vacancy defects (V_Se) and an externally applied vertical electric field on adsorption behavior. Pristine PdSe₂ exhibits physisorption of NO₂ and NO molecules, characterized by low adsorption energies and limited charge transfer. The introduction of Se vacancies significantly enhances the adsorption capacity of PdSe₂, increasing the adsorption energies of NO₂ and NO to − 1.58 eV and  − 1.76 eV, respectively. The adsorption mechanism transitions from physisorption to chemisorption, with gas molecules forming stable covalent bonds with the PdSe₂ surface, accompanied by a substantial increase in charge transfer. Upon adsorption of NO₂ and NO gases, the magnetic moment of PdSe₂ increases from 0 to approximately 0.70 μB, inducing magnetism in the substrate. An externally applied positive electric field further strengthens the adsorption; in contrast, a negative electric field weakens adsorption performance, indicating that PdSe₂'s adsorption properties can be modulated by an external electric field. Finally, compared with NO₂ and NO adsorbed on intrinsic PdSe₂, the recovery times for NO₂ and NO on defective PdSe₂ (V_Se-PdSe₂) are longer, and the interactions are stronger, indicating that V_Se-PdSe₂ is a promising adsorbent for the removal of NO₂ and NO. In summary, the adsorption of NO₂ and NO can modulate the magnetic properties of PdSe₂, while Se vacancies enhance its adsorption capability toward these gases. This work will provide a theoretical basis as well as preliminary ideas for experimenters.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-thermal plasma-mediated inactivation of biofilms formed by imipenem-resistant Klebsiella pneumoniae: a non-antibiotic approach","authors":"Mohammed F. Al-Marjani,&nbsp;Raghad S. Mohammed,&nbsp;Nodira Azimova,&nbsp;Jamoliddin Razzokov,&nbsp;Sanaa Ali Hamza","doi":"10.1140/epjp/s13360-025-06933-6","DOIUrl":"10.1140/epjp/s13360-025-06933-6","url":null,"abstract":"<div><p>Bacteria often form complex communities known as biofilms—hydrated extracellular polymeric matrices that protect sessile cells. Non-thermal plasma (NTP) is emerging as a potential strategy for biofilm disruption due to the oxidative damage caused by reactive oxygen and nitrogen species (RONS). In this study, the antimicrobial activity of an argon-based atmospheric pressure NTP jet was evaluated against imipenem-resistant <i>Klebsiella pneumoniae</i> biofilms in vitro. Plasma exposure times ranged from 0 to 120 s. A 15-s treatment reduced bacterial growth by 72% (<i>p</i> &lt; 0.0001), with complete inhibition observed reach 100% at 60–120 s. Biofilm degradation reached 42% at 15 s and 100% at 60 s. Scanning electron microscopy revealed significant morphological damage, including cell deformation and shrinkage. These findings highlight NTP’s potential as an effective, non-antibiotic method for combating multidrug-resistant <i>K. pneumoniae</i> infections.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ZnO/NaX zeolite composite for basic red 46 degradation: a coupled adsorption–photocatalysis approach","authors":"Yacine Baghdadi,&nbsp;Noureddine Bentaieb,&nbsp;El Hadj Mekatel,&nbsp;Mohamed Belmedani,&nbsp;Mohamed Trari,&nbsp;Seif El Islam Lebouachera","doi":"10.1140/epjp/s13360-025-06885-x","DOIUrl":"10.1140/epjp/s13360-025-06885-x","url":null,"abstract":"<div><p>Industrial effluents from textile, tanning, and printing industries often contain synthetic dyes that are recalcitrant to biodegradation. In this study, we prepared and characterized “ZnO/NaX zeolite” composite and evaluated its performance for the removal of Basic Red 46 (BR46) through a combined “adsorption/photocatalysisuns” under solar irradiation. The physical and chemical properties of the prepared samples were investigated by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and FT-IR spectroscopy. The influence of operational parameters namely the catalyst content (0.1–1 g/L), pH of the solution (48) and initial BR 46 concentration (5–40 mg/L) on the photodegradation efficiency was studied. The maximum dye removal was observed at pH ~ 7, for an BR 46 concentration of 20 mg/L, using 1 g/L of “ZnO/NaX Zeolite”. Maximum BR46 degradation under sunlight was studied was achieved about 96% at 20 mg/L of BR46 dye, 1 g/L catalyst content and pH of 7 within 180 min of contact time. The photocatalytic degradation kinetics of BR 46 is well described by a first order, in accordance with the Langmuir–Hinshelwood model (k_app = 0.0011 min⁻¹). The reusability of the predicted catalyst was also investigated. These findings demonstrate the effectiveness of “ZnO/NaX zeolite” composites for the solar-assisted treatment of dye-contaminated wastewater and open avenues for broader environmental applications.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of structural, morphological, dielectric, and magnetic properties of complex material for multifunctional applications","authors":"Sushil Joshi,&nbsp;Alok Shukla,&nbsp;Nitin Kumar,&nbsp;Ram Naresh Prasad Choudhary","doi":"10.1140/epjp/s13360-025-06904-x","DOIUrl":"10.1140/epjp/s13360-025-06904-x","url":null,"abstract":"<p>This communication presents an in-depth study of the structural, dielectric, transport mechanism, and magnetic response of Bi_0.8Gd_0.2Fe_0.5Ti_0.5O₃ ceramic material. The material preparation employed a solid-state reaction approach conducted at elevated thermal conditions. The XRD study provides evidence that the compound has undergone phase formation. Scanning electron microscopy image confirms the polycrystalline nature of the sample. It reveals the production of grains that are dispersed over the whole surface and have sizes that are not uniform. The average grain size was determined to be around 1–2 µm. The energy dispersive X-ray spectroscopy (EDS) demonstrates the existence of all of the required components, with no foreign elements. Dielectric properties are carried away in a broad range of frequency and temperature. The material exhibits a low value of tangent loss of 0.032 at room temperature. The Nyquist plot provides a comprehensive understanding of the properties of electrical characteristics that are dependent on frequency and temperature. Impedance spectroscopy effectively distinguishes the contributions of grains, grain boundaries, and electrodes to the material's overall electrical properties. The magnetic behavior of the material reveals its ferromagnetic nature with <i>M</i>_r = 46.281 E−3 emu/g. The <i>P-E</i> loop indicates weak ferroelectric behavior with a low remanent polarization (<i>P</i>_r = 0.0118 μC/cm²). Because of the electrical and magnetic characteristics that the compound possesses, the material Bi_0.8Gd_0.2Fe_0.5Ti_0.5O₃ is flexible enough to be used in a variety of applications inside multifunctional devices.</p>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reduced basis steady Smagorinsky turbulence model for forced convection flow: application to the thermal comfort optimisation of cloisters","authors":"Cristina Caravaca García,&nbsp;Tomás Chacón Rebollo,&nbsp;Macarena Gómez Mármol","doi":"10.1140/epjp/s13360-025-06879-9","DOIUrl":"10.1140/epjp/s13360-025-06879-9","url":null,"abstract":"<div><p>In this paper, we address the construction of reduced basis (RB) turbulence models for thermal air flow, as a tool to design optimal thermal comfort-oriented spaces in the architectural design of buildings. We consider thermal turbulent flow, modelled by the Smagorinsky LES turbulence model with forced convection, plus the internal energy conservation equation. We assume that the flow takes place in a transition space in buildings with some geometrical complexity, actually a cloister. We approximate this model by a stable discretisation using the finite element method using FreeFem++, leading to the full order model (FOM). We build mathematically based <i>a posteriori</i> error indicators for both velocity-pressure and temperature. On this basis, we construct a RB turbulence model for the targeted 2D thermal flow. We obtain speed-up rates of computation time of nearly 150 with respect to the FOM. We then apply the RB model to the optimal thermal comfort design of a cloister in typically hot climates. We determine the geometry of the cloister that allows the smallest deviation of the temperature with respect to a given comfort temperature: the corridors must be as wide and low as possible.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-06879-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anisotropic configurations of new class of compact stars in modified teleparallel gravity","authors":"Amina Amin,&nbsp;Rubab Manzoor,&nbsp;Allah Ditta,&nbsp;Phongpichit Channuie,&nbsp;Asifa Ashraf","doi":"10.1140/epjp/s13360-025-06878-w","DOIUrl":"10.1140/epjp/s13360-025-06878-w","url":null,"abstract":"<div><p>This paper provides modeling of compact stars in the framework of modified teleparallel gravity theory. The <i>f</i>(<i>T</i>) gravity mechanism employs torsion rather than spacetime curvature to explain gravitational phenomena analogous to general relativity. In this study, we developed new compact stars solutions by evaluating the <span>(g_{tt})</span> components of the spherically symmetric interior geometry by using the <i>f</i>(<i>T</i>) gravity field equations and linear equation of state. Further, we also evaluated the exterior solution from the available set of field equations rather than matching with the Schwarzschild solution or any other available exterior geometry. The physical parameters of the model are analyzed graphically by using observational data of four prominent compact stars <span>(SAX; J1808.4-3658,; Vela; X-1,; PSR; J1614-2230,; text {and}; PSR; J0952-0607)</span>. This viable study of compact objects includes the investigation of metric potential functions, energy density, equation of state, radial and tangential pressures, as well as their anisotropic effects. The Tolman–Volkoff equation (TOV) verifies the hydrostatic equilibrium, and it is also verified that all the standard energy conditions are satisfied in the stellar interior. Moreover, the causality condition is satisfied through analysis of sound speed and adiabatic index which lie in a stable regime, and therefore, the model proposed is physically viable and stable. This study explores how gravitational redshift behaves, and proposes explanations regarding stellar compactness and mass functions, and checks gradients spanning through the star radius. We observed that very close to the boundary, trace energy condition, dominant energy condition, and Abreu criteria show the instability for some compact star candidates; otherwise, as a whole, our proposed model is stable and physical. The studied gravity model meets all the physical and stability criteria, which verify that stellar configurations present realistic and uniform behavior. The research validates <i>f</i>(<i>T</i>) gravity as an effective theory to simulate compact astrophysical objects with valuable insights into gravity behavior in strong-field situations.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cerium-modified BiPO4 as a promising electrode material for hybrid supercapacitors","authors":"Ifra Arshad,&nbsp;Asmat Ullah,&nbsp;Muhammad Khawar Abbas,&nbsp;Shahid Iqbal,&nbsp;Aqeel Ahmad Shah,&nbsp;Asad Akram,&nbsp;Naveed Akhtar Shad,&nbsp;Kh. Abd El-Aziz,&nbsp;Hafiz T. Ali,&nbsp;Yasir Javed","doi":"10.1140/epjp/s13360-025-06901-0","DOIUrl":"10.1140/epjp/s13360-025-06901-0","url":null,"abstract":"<div><p>In this research work, the electrochemical response of BiPO₄ was optimized by varying the Ce concentration to 1, 2, and 3%. The XRD analysis confirmed the monoclinic structure of the prepared BiPO₄ nanoparticles with space group P21/a and P21/m. EDX studies indicated the presence of Ce with different concentrations in the doped BiPO₄. The electrochemical investigations showed that Ce (3%)-doped BiPO₄ exhibited the best electrochemical properties with a 784.2 F/g of specific capacitance at a scan rate of 5 mV/s. The charge storage nature presented hybrid behavior of the electrode material with b = 0.7, with 74% capacitive and 26% diffusive contributions. The prototype device based on a two-electrode setup presented a maximum energy density of 24.11 Wh/kg at 1 A/g and 4900 W/kg of power density at 7 A/g, with a 79.43% capacity retention for 1000 GCD cycles. The XPS analysis revealed the occurrence of multiple oxidation states of Ce (Ce³⁺ and Ce⁴⁺) and Bi (Bi³⁺ and Bi⁵⁺), responsible for enhanced electrochemical response of Ce-doped BiPO₄ nanomaterials for hybrid supercapacitors. The 3% cerium-doped BiPO₄ showed enhanced conductivity and facilitated electrochemical redox reactions, indicating its potential for energy storage applications.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}