Chinese Journal of Physics最新文献

{"title":"Response surface methodology for Darcy–Forchheimer convective flow of Williamson nanofluid: A sensitivity analysis","authors":"Dilawar Hussain ,&nbsp;Hulin Huang ,&nbsp;Aliya Batool ,&nbsp;Zakir Hussain","doi":"10.1016/j.cjph.2025.06.001","DOIUrl":"10.1016/j.cjph.2025.06.001","url":null,"abstract":"<div><div>This paper explores the Response Surface Method (RSM) for the Darcy–Forchheimer convective flow of Williamson nanofluid. The convective nanofluid flow is optimized using the Response Surface Methodology, and the effective parameters in the flow are explored through sensitivity analysis. The current study is investigated in two dimensions. Firstly, a mathematical model is developed for the Williamson nanofluid under the influence of Darcy–Forchheimer effects and convection over a stretching sheet. The developed model is simplified by similarity variables, and numerical results are obtained through the bvp4c MATLAB function. Secondly, an empirical relation is developed for heat and mass transport by variance analysis through the RSM approach for dimensionless variables that appeared in the flow model. Sensitivity analysis is performed for heat and mass transfer against the dimensionless variables, namely the inertia coefficient <span><math><mrow><mo>(</mo><mn>0</mn><mo>.</mo><mn>1</mn><mo>≤</mo><mi>F</mi><mi>r</mi><mo>≤</mo><mn>3</mn><mo>.</mo><mn>5</mn><mo>)</mo></mrow></math></span>, porosity parameter <span><math><mrow><mo>(</mo><mn>1</mn><mo>≤</mo><mi>β</mi><mo>≤</mo><mn>3</mn><mo>)</mo></mrow></math></span>, and radiation parameter <span><math><mrow><mo>(</mo><mn>1</mn><mo>≤</mo><mi>R</mi><mi>d</mi><mo>≤</mo><mn>4</mn><mo>)</mo></mrow></math></span>. The findings show that the inertia coefficient, porosity parameter, and radiation parameter are dominant in the flow model for heat and mass transport. Furthermore, the radiation parameter is more prominent than the inertia and porosity parameters for mass transport, while the opposite behavior is observed for heat transport.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 875-890"},"PeriodicalIF":4.6,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144365654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Stochastic asymptotical stability of the predator-free and positive equilibrium for food chain model with vigilance under stochastic perturbations","authors":"Jianguo Tan,&nbsp;Xiaohan Jiang","doi":"10.1016/j.cjph.2025.05.028","DOIUrl":"10.1016/j.cjph.2025.05.028","url":null,"abstract":"<div><div>Most stability analyzes of stochastic differential equations (SDEs) are based on the construction of Lyapunov functions, but it is difficult to find suitable Lyapunov functions in some cases. This paper studies a class of stochastic food chain models with vigilance. First, the asymptotical mean square (MS) stability of the corresponding linearization problem was analyzed using Kronecker product and semi-vectorization dimensionality reduction methods, and the sufficient conditions and stable regions of the local stochastic asymptotic stability of the stochastic nonlinear food chain model were derived. Afterwards, the effects of noise intensity and dual parameters changes on the stochastic asymptotical stability (SAS) of the system were analyzed through numerical simulation, and the following conclusions were drawn: mid-level predators respond most strongly to disturbance, while bottom prey are the least sensitive to disturbance. Overall, the increase in perturbation reduces the geometric volume of the stochastically asymptotically stable domain.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 757-769"},"PeriodicalIF":4.6,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144331407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Dynamics of test particles and scalar perturbation around an Ayón–Beato–García black hole coupled with a cloud of strings","authors":"Faizuddin Ahmed ,&nbsp;Ahmad Al-Badawi ,&nbsp;İzzet Sakallı ,&nbsp;Sanjar Shaymatov","doi":"10.1016/j.cjph.2025.05.035","DOIUrl":"10.1016/j.cjph.2025.05.035","url":null,"abstract":"<div><div>In this paper, we examine the geodesic motion and scalar perturbations of the Ayón–Beato–García black hole coupled with a cloud of strings, using the effective potential approach to analyze the trajectories of massless and massive test particles. The combined effects of nonlinear electrodynamics and the cloud of strings significantly modify the spacetime geometry, leading to distinct dynamical properties for test particles, including the stability and escape conditions of null and time-like geodesics. We also study scalar perturbations by deriving the Klein–Gordon equation for massless scalar fields in this spacetime, revealing an effective potential that depends on the parameters of nonlinear electrodynamics and the cloud of strings. Additionally, we compute the greybody factors to explore the energy transmission and absorption properties of the black hole, showing that both the nonlinear electrodynamics and the cloud of strings play a pivotal role in modulating these factors, thereby influencing the energy spectrum of scalar radiation.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 770-791"},"PeriodicalIF":4.6,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144331328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Self-excited and hidden multi-scroll attractors in a novel extremely simple three-dimensional system","authors":"Xiaoyu Hu ,&nbsp;Siteng Wang ,&nbsp;Panpan Wu ,&nbsp;Hongbo Cao ,&nbsp;Xinyu Zhang ,&nbsp;Jun Chen","doi":"10.1016/j.cjph.2025.05.036","DOIUrl":"10.1016/j.cjph.2025.05.036","url":null,"abstract":"<div><div>Multi-scroll hidden attractor (MSHA) system generally exhibits unpredictable motion trajectories and complex dynamical characteristics, which holds promising application prospects in information encryption. However, there are still some issues, such as complex structure and difficulty in regulation. Thus, constructing simple MSHA systems with complex dynamics has become a research focus in recent years. In this article, a new simple multi-scroll chaotic system with only one sinusoidal non-linear term is proposed. In particular, with respect to different system parameters, the proposed system can generate self-excited or hidden multi-scroll attractors flexibly. Furthermore, periodic or chaotic states can be observed within individual scrolls of multi-scroll attractor, depending on the various system parameters. In addition, both the system parameters and the transient simulation time can be conveniently adjusted to control the scroll counts. It should be noted that the proposed simple three-dimensional chaotic system can exhibit interesting initial-boosted dynamic behavior. Also, the coordinates of the attractor can be shifted due to offset-boosted behavior. This can be achieved by adjusting the independent non-bifurcated parameter <span><math><mi>d</mi></math></span>. Both initial-boosted and offset-boosted behaviors are capable of altering the location of the attractor within the state space without transforming its shape. This implies that the scope of state variable values can be easily adjusted, potentially offering significant convenience to engineering applications. Finally, an analog circuit has been designed to realize the suggested multi-scroll chaotic system. The results further attest to the operability of the system on the physical platform and the reliability of numerical analysis.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 826-839"},"PeriodicalIF":4.6,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144364479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Flow diverters as a technique to balance the flow in bifurcation branches in a stenosed coronary artery","authors":"Shankar Narayan S","doi":"10.1016/j.cjph.2025.06.017","DOIUrl":"10.1016/j.cjph.2025.06.017","url":null,"abstract":"<div><div>Owing to the intricate hemodynamic circumstances and local flow disruptions that are prevalent, coronary bifurcations are among the most often damaged sites by atherosclerosis. The present research is intended to discover a novel way to save the coronary branches from undergoing further deterioration due to the existing stenosis along the branches of the bifurcation, to prevent vascular diseases and further complications. Cylindrical elastic biodegradable flow diverters of uniform radius are deployed in the flow channel near the entry of the bifurcation region. Employing finite element methods, fluid dynamics equations and structural equations are solved. Although flow diverters have historically been employed for managing aneurysms by encouraging thrombosis, the current work presents a novel use of flow diverters to reduce the risk of stenosis by balancing hemodynamic asymmetry. It is found that the butterfly effect of flow distribution and sliding flows perfectly balances the flow between the coronary branches. The difference in the total shear force along the walls due to the installed diverters is found to be in the range of <span><math><mrow><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup><mspace></mspace><mi>N</mi><mo>/</mo><mi>m</mi></mrow></math></span>. The highest strain experienced by the arterial walls ranges from <span><math><mrow><mn>4</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup></mrow></math></span> to <span><math><mrow><mn>1</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup></mrow></math></span> as the number of flow diverters is increased. A <span><math><mrow><mn>0.04</mn><mo>%</mo><mspace></mspace></mrow></math></span>to <span><math><mrow><mn>0.3</mn><mo>%</mo></mrow></math></span> elongation or compression of the arterial wall is seen as the diverters were installed. This deformation is very small to impact the arterial tissue, as a stent-induced strain is considered safe if maintained below 10%. The results concluded that the inclusion of flow diverters does not affect the mechanical indicators.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 906-973"},"PeriodicalIF":4.6,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144479944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Different vibration-switching modes induced by pulse-shaped explosion in a hybrid van der Pol-Rayleigh-Duffing system","authors":"Zhenzhen Zhang ,&nbsp;Xindong Ma ,&nbsp;Zhao Zhang","doi":"10.1016/j.cjph.2025.06.016","DOIUrl":"10.1016/j.cjph.2025.06.016","url":null,"abstract":"<div><div>Mixed-mode vibrations belong to a typical multiscale dynamic phenomenon, which are manifested as a combination of limit cycle vibrations (defined as excited states) and equilibrium point vibrations (defined as silent states). Revealing the switching mechanism between the two different vibration states is an important topic in nonlinear dynamics. This work proposes a novel switching mechanism based on a hybrid van der Pol-Rayleigh-Duffing oscillator with slow-varying harmonic excitations, known as pulse-shaped explosion (PSE for short). PSE behavior is manifested as the system roots tending to the positive or negative infinities near some certain critical values, which can formally transform a smooth system into a combination of several non-smooth systems. To explore the occurrence of the PSE, we calculate the equilibrium state characteristics of the model and obtain the variation law of the system real solution with the cosine excitation function by the function monotonicity theory. From the general analyses of the relaxation oscillations and mixed-mode vibrations, we show that three different vibration-switching modes namely the switching between the excited and silent states induced by the PSEs, the switching between the two excited states induced by the PSEs and the switching between the two silent states induced by the PSEs can be exhibited. In addition, we show that the bifurcation-delay phenomenon caused by the cosine function slowly varying through the supercritical Hopf bifurcations can significant prolong the silent state process and the slow passage effect can terminate the trajectories’ tendency to the positive and negative infinities with the PSE to form a complete periodic structure. Our findings contribute to a better analysis of the mixed-mode vibrations and provide valuable insights for the mechanism research and encourage or inhibit strategic planning of the mixed-mode vibrations.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 891-905"},"PeriodicalIF":4.6,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144471830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"A novel hyperchaotic multistable heterogeneous neural network with hidden attractors and its application in image encryption","authors":"Zhi Huang ,&nbsp;Zhen Li ,&nbsp;Qiao Wang ,&nbsp;Weijie Tan ,&nbsp;Xianming Wu","doi":"10.1016/j.cjph.2025.05.037","DOIUrl":"10.1016/j.cjph.2025.05.037","url":null,"abstract":"<div><div>By simulating the unique properties of different types of neurons and their interconnecting patterns, heterogeneous neural networks can more accurately reflect the structural and functional characteristics of biological neural systems. Therefore, a novel hyperbolic non-volatile locally active memristor is proposed, enabling the construction of a heterogeneous Hindmarsh–Rose neuron memristive synapse-coupled Hopfield neural network (HR-M-HNN) via synaptic characteristic emulation. Dynamic analysis reveals that the HR-M-HNN exhibits hidden attractor characteristics due to the absence of equilibrium points and can generate complex dynamics behaviors, including hyperchaos, chaos, periodic and quasi-periodic, and multistability. Further research reveals a strong correlation between the chaotic state of HR-M-HNN and the locally active control parameter of the memristor. To verify the accuracy of the dynamic analysis, the corresponding analog circuit is designed. Furthermore, based on the HR-M-HNN hyperchaotic system, a novel image encryption scheme is proposed, which utilizes the position index of the Latin square to perform synchronous permutation and diffusion on the plain image, reducing redundant operations and effectively enhancing the encryption speed. Security analyses demonstrate that the proposed image encryption scheme offers excellent performance and robustness.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 851-874"},"PeriodicalIF":4.6,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144365653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Impact of the tangential velocity and Karmarkar condition in constructing wormhole solutions within Rastall-Rainbow gravity","authors":"Sweeti Kiroriwal ,&nbsp;Jitendra Kumar ,&nbsp;S.K. Maurya ,&nbsp;Akram Ali","doi":"10.1016/j.cjph.2025.05.032","DOIUrl":"10.1016/j.cjph.2025.05.032","url":null,"abstract":"<div><div>In this paper, we analyze the existence of asymptotically flat wormhole solutions in the realm of Rastall-Rainbow modified gravity through an approach that combines aspects of Rastall gravity with the Rainbow framework. Using the Karmarkar condition for embedding class one metrics, we analytically solve the modified field equations that characterize wormholes. We examine the feasibility of our proposed shape functions through a graphical analysis. Interestingly, we used the rotational velocity formula to calculate the redshift function. We also examined the energy conditions to analyze the physical content of the wormhole and determined that the exact wormhole models are composed of exotic matter. This exotic matter violates the necessary energy conditions near the wormhole throat, ensuring that the wormholes remain traversable and consistent with their theoretical framework. Our findings also demonstrated the positive deflection angle for photons following null geodesics.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 1289-1302"},"PeriodicalIF":4.6,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Quantum mechanics in curved space(time) with a noncommutative geometric perspective","authors":"Otto C.W. Kong","doi":"10.1016/j.cjph.2025.05.029","DOIUrl":"10.1016/j.cjph.2025.05.029","url":null,"abstract":"<div><div>We have previously presented a version of the Weak Equivalence Principle for a quantum particle as an exact analog of the classical case, based on the Heisenberg picture analysis of free particle motion. Here, we take that to a full formalism of quantum mechanics in a generic curved space(time). Our basic perspective is to take seriously the noncommutative symplectic geometry corresponding to the quantum observable algebra. Particle position coordinate transformations and a nontrivial metric assigning an invariant inner product to vectors, and covectors, are implemented accordingly. That allows an analog to the classical picture of the phase space as the cotangent bundle. The mass-independent quantum geodesic equations as equations of free particle motion under a generic metric as a quantum observable are obtained from an invariant Hamiltonian. Hermiticity of momentum observables is to be taken as reference frame dependent. Our results have a big contrast to the alternative obtained based on the Schrödinger wavefunction representation which we argue to be less appealing. Hence, the work points to a very different approach to quantum gravity, plausibly with a quantum Einstein equation suggested.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 690-699"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144312907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Ghost surface polaritons in Ca-intercalated α-vanadium pentoxide","authors":"Song Bai,&nbsp;Yubo Li,&nbsp;Haoyuan Song,&nbsp;Qiang Zhang,&nbsp;Shufang Fu,&nbsp;Xuanzhang Wang","doi":"10.1016/j.cjph.2025.06.010","DOIUrl":"10.1016/j.cjph.2025.06.010","url":null,"abstract":"<div><div>We have examined the conditions required for the existence of ghost surface polaritons (GSPs) with oscillations and attenuation properties in a low-symmetrical α-V₂O₅ crystal in the three special geometries, where the two principal axes are situated off the surface of the crystal and the other is parallel to the surface. It is discovered that GSPs, which are made up of two coherent evanescent branch waves, can be observed in the three reststrahlen frequency bands once an angle exists between the crystal axis and the coordinate axis. The underlying mechanism governing the modulation of GSPs propagation characteristics has been explored following the intercalation of calcium (Ca) atoms into α-V₂O₅ crystals. The investigation demonstrates that Ca-intercalation can dramatically alter the main characteristics of GSPs, particularly in terms of the frequency response behavior and propagation modes. As proven by attenuated total reflection spectra, the GSPs produced in α-V₂O₅ or α'-(Ca)V₂O₅ crystal can be detectable by selecting the appropriate observation conditions, such as the gap between the prism and the crystal. The findings provide innovative insights for developing advanced optoelectronic materials and devices.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"96 ","pages":"Pages 716-731"},"PeriodicalIF":4.6,"publicationDate":"2025-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144321496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}