Pub Date : 2025-12-17DOI: 10.1016/j.cjph.2025.12.016
Mohsen Saeidi babi, Mohammad Reza Pahlavani
This study investigates the 14N-accompanied ternary fission of 258Fm and 256Cf isotopes within equatorial geometry, emphasizing the role of fragments deformation. For both isotopes, all fragment combinations with positive Q-values were analyzed using quadrupole (β2) and hexadecapole (β4) deformation parameters. The angular dependence of driving potentials and transmission coefficient was calculated across to 180∘, with total penetration probabilities derived by integrating over angular configurations. Obtained results for deformed fragments were systematically compared with spherical counterparts to isolate deformation effects. Key results highlight the dominance of configurations involving magic or near-magic nuclei, where deformation significantly enhances penetration probabilities and reduces decay constants. Angular trends reveal suppressed probabilities, mitigated by deformation-induced barrier lowering. Comparisons of calculated results between 256Cf and 258Fm isotopes underscore the universal influence of shell closures and deformation, regardless of parent nucleus mass. These findings advance the understanding of ternary fission dynamics, emphasizing the synergy of nuclear structure, angular geometry, and deformation.
{"title":"14N-accompanied ternary fission of 256Cf and 258Fm isotopes considering deformation of fragments","authors":"Mohsen Saeidi babi, Mohammad Reza Pahlavani","doi":"10.1016/j.cjph.2025.12.016","DOIUrl":"10.1016/j.cjph.2025.12.016","url":null,"abstract":"<div><div>This study investigates the <sup>14</sup>N-accompanied ternary fission of <sup>258</sup>Fm and <sup>256</sup>Cf isotopes within equatorial geometry, emphasizing the role of fragments deformation. For both isotopes, all fragment combinations with positive Q-values were analyzed using quadrupole (<em>β</em><sub>2</sub>) and hexadecapole (<em>β</em><sub>4</sub>) deformation parameters. The angular dependence of driving potentials and transmission coefficient was calculated across <span><math><mrow><mi>θ</mi><mo>=</mo><msup><mn>0</mn><mo>∘</mo></msup></mrow></math></span> to 180<sup>∘</sup>, with total penetration probabilities derived by integrating over angular configurations. Obtained results for deformed fragments were systematically compared with spherical counterparts to isolate deformation effects. Key results highlight the dominance of configurations involving magic or near-magic nuclei, where deformation significantly enhances penetration probabilities and reduces decay constants. Angular trends reveal suppressed probabilities, mitigated by deformation-induced barrier lowering. Comparisons of calculated results between <sup>256</sup>Cf and <sup>258</sup>Fm isotopes underscore the universal influence of shell closures and deformation, regardless of parent nucleus mass. These findings advance the understanding of ternary fission dynamics, emphasizing the synergy of nuclear structure, angular geometry, and deformation.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 213-224"},"PeriodicalIF":4.6,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797820","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}
Pub Date : 2025-12-15DOI: 10.1016/j.cjph.2025.12.019
Jiexin Wang , Huan Wang , Xiaojie Liu , Yin Wang , Haitao Yin
Two-dimensional semiconductors are key candidate materials for overcoming the size limitations of silicon-based field-effect transistors; however, their high contact resistance at the interface has become the primary bottleneck restricting the performance of sub-2nm node devices. To address this challenge, we designed a self-intercalated bilayer InSe/monolayer InSe heterostructure and systematically investigated its interfacial and charge transport properties using a combined density functional theory (DFT) and non-equilibrium Green's function (NEGF) approach. Analysis of the interfacial electronic structure revealed that the effective potential in the bulk semiconductor region is higher than at the metal-semiconductor interface. The tunneling barrier between metal and semiconductor vanishes, which significantly enhances carrier injection capability. Moreover, the work function difference between metal and semiconductor induces band realignment at the interface, enabling ohmic contact along the device’s armchair (AC) and zigzag (ZZ) directions. The equilibrium conductance measurements yield remarkably low contact resistances of 40.74 Ω·μm and 52.32 Ω·μm for the ZZ and AC directions, respectively. These values compare favorably with the best-reported contacts in 2D materials and approach the fundamental quantum limit of approximately 30 Ω·μm for monolayer systems. The research outcomes substantiate that the self-intercalation-engineered device architecture provides a groundbreaking strategy for fabricating new-generation nanoelectronics featuring ultralow contact resistance and minimized power dissipation.
{"title":"Ultralow contact resistance ohmic contact via self-intercalated InSe heterostructure","authors":"Jiexin Wang , Huan Wang , Xiaojie Liu , Yin Wang , Haitao Yin","doi":"10.1016/j.cjph.2025.12.019","DOIUrl":"10.1016/j.cjph.2025.12.019","url":null,"abstract":"<div><div>Two-dimensional semiconductors are key candidate materials for overcoming the size limitations of silicon-based field-effect transistors; however, their high contact resistance at the interface has become the primary bottleneck restricting the performance of sub-2nm node devices. To address this challenge, we designed a self-intercalated bilayer InSe/monolayer InSe heterostructure and systematically investigated its interfacial and charge transport properties using a combined density functional theory (DFT) and non-equilibrium Green's function (NEGF) approach. Analysis of the interfacial electronic structure revealed that the effective potential in the bulk semiconductor region is higher than at the metal-semiconductor interface. The tunneling barrier between metal and semiconductor vanishes, which significantly enhances carrier injection capability. Moreover, the work function difference between metal and semiconductor induces band realignment at the interface, enabling ohmic contact along the device’s armchair (AC) and zigzag (ZZ) directions. The equilibrium conductance measurements yield remarkably low contact resistances of 40.74 Ω·μm and 52.32 Ω·μm for the ZZ and AC directions, respectively. These values compare favorably with the best-reported contacts in 2D materials and approach the fundamental quantum limit of approximately 30 Ω·μm for monolayer systems. The research outcomes substantiate that the self-intercalation-engineered device architecture provides a groundbreaking strategy for fabricating new-generation nanoelectronics featuring ultralow contact resistance and minimized power dissipation.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 356-365"},"PeriodicalIF":4.6,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837439","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}
The so-called Generalized Uncertainty Principle (GUP) is an alternative to the Heisenberg uncertainty principle that incorporates the idea of a minimum measurable length scale, often referred to as the Minimal Length (ML). In this paper, we investigate the first-order correction introduced by the GUP to the non-relativistic quantum mechanics of the single and double Dirac Delta Potentials (DDPs) in one dimension. For the single DDP, we show that the direct Schrödinger solution and the Green’s function method yield identical results for both bound and scattering states, clarifying the reasons behind earlier conflicting findings. For the double DDP, we find that the leading GUP correction to bound-state energies and scattering probabilities is of the order of the ML. Considering only this correction, the effect of the GUP is reduced to a slight decrease in the strength of the double DDP.
{"title":"The single and double Dirac delta potentials under the assumption of minimal length","authors":"Yassine Chargui , Anis Dhahbi , Salah Boulaaras , Abdelmalek Boumali","doi":"10.1016/j.cjph.2025.12.014","DOIUrl":"10.1016/j.cjph.2025.12.014","url":null,"abstract":"<div><div>The so-called Generalized Uncertainty Principle (GUP) is an alternative to the Heisenberg uncertainty principle that incorporates the idea of a minimum measurable length scale, often referred to as the Minimal Length (ML). In this paper, we investigate the first-order correction introduced by the GUP to the non-relativistic quantum mechanics of the single and double Dirac Delta Potentials (DDPs) in one dimension. For the single DDP, we show that the direct Schrödinger solution and the Green’s function method yield identical results for both bound and scattering states, clarifying the reasons behind earlier conflicting findings. For the double DDP, we find that the leading GUP correction to bound-state energies and scattering probabilities is of the order of the ML. Considering only this correction, the effect of the GUP is reduced to a slight decrease in the strength of the double DDP.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 563-572"},"PeriodicalIF":4.6,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145921009","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}
Pub Date : 2025-12-15DOI: 10.1016/j.cjph.2025.12.017
Yong Zhang, Hongcheng Zhou, Zhongming Yan, Yu Wang
Piezoelectric antennas break through the mutual constraint relationship between traditional antenna wavelength and size, featuring low-frequency miniaturization and high radiation efficiency. However, narrowband and low radiation intensity severely limit the communication distance and channel capacity in practical application scenarios. Therefore, a multi-modal coupled piezoelectric antenna with stacked structure is proposed to enhance the radiation intensity and achieve multi-frequency wideband characteristics. The cavity structure formed by stacking, along with the design of the energy-trapping electrodes can reduce the acoustic propagation losses, and the antenna is capable of high radiation efficiency and multi-frequency operation, while also realize the guiding effect on electromagnetic waves. By integrating the piezoelectric constitutive equations with the equivalent density parameter method, a theoretical model was developed to characterize the heterogeneous properties of electrode regions, revealing the regulatory mechanism by which mass–stiffness coupling influences energy-trapping effect, and the corresponding electromechanical model reveals the radiation enhancement mechanism of the laminated structure on the piezoelectric antenna. The experimental results indicate that the antenna has six operating frequencies, with an effective communication range of 60m. The antenna demonstrates a 3-4 orders higher magnetic field emitting efficiency compared to a conventional loop coil antenna in VLF/LF band. The near-field radiation pattern demonstrates significant directionality (front to back ratio of 12dB).Furthermore, a digital amplitude shift keying (ASK) modulation and frequency-shift keying (FSK) are conducted with a low frequency (LF) carrier signal to enable anti-interference communication. These results demonstrate the enormous potential of the proposed antenna in portable, intelligent, and high-performance wireless communication devices.
{"title":"Research on the broadband radiation-enhanced piezoelectric antenna based on multimodal coupled vibration","authors":"Yong Zhang, Hongcheng Zhou, Zhongming Yan, Yu Wang","doi":"10.1016/j.cjph.2025.12.017","DOIUrl":"10.1016/j.cjph.2025.12.017","url":null,"abstract":"<div><div>Piezoelectric antennas break through the mutual constraint relationship between traditional antenna wavelength and size, featuring low-frequency miniaturization and high radiation efficiency. However, narrowband and low radiation intensity severely limit the communication distance and channel capacity in practical application scenarios. Therefore, a multi-modal coupled piezoelectric antenna with stacked structure is proposed to enhance the radiation intensity and achieve multi-frequency wideband characteristics. The cavity structure formed by stacking, along with the design of the energy-trapping electrodes can reduce the acoustic propagation losses, and the antenna is capable of high radiation efficiency and multi-frequency operation, while also realize the guiding effect on electromagnetic waves. By integrating the piezoelectric constitutive equations with the equivalent density parameter method, a theoretical model was developed to characterize the heterogeneous properties of electrode regions, revealing the regulatory mechanism by which mass–stiffness coupling influences energy-trapping effect, and the corresponding electromechanical model reveals the radiation enhancement mechanism of the laminated structure on the piezoelectric antenna. The experimental results indicate that the antenna has six operating frequencies, with an effective communication range of 60m. The antenna demonstrates a 3-4 orders higher magnetic field emitting efficiency compared to a conventional loop coil antenna in VLF/LF band. The near-field radiation pattern demonstrates significant directionality (front to back ratio of 12dB).Furthermore, a digital amplitude shift keying (ASK) modulation and frequency-shift keying (FSK) are conducted with a low frequency (LF) carrier signal to enable anti-interference communication. These results demonstrate the enormous potential of the proposed antenna in portable, intelligent, and high-performance wireless communication devices.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 426-437"},"PeriodicalIF":4.6,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880790","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}
Pub Date : 2025-12-15DOI: 10.1016/j.cjph.2025.12.018
Ren Guo , Miaofang Zhou , Guangtao Cao , Fan He , Jingfeng Tian , Shuyu Qiao , Hui Yang , Hairong He , Zhiying Zhu , Shaobo Liu , Tao Yu , Min Pan , Hongchao Yi , Gengbiao Lu , Yan Deng , Enduo Gao
Plasmon-induced transparency (PIT) faces limitations in integrated photonics due to low Q factors (<50) and restricted polarization control. This work integrates quasi-bound states in the continuum (QBIC) with guided-mode resonance (GMR), effectively utilizing the material advantages of silicon and silver to achieve the like-plasmon-induced absorption (like-PIA) phenomenon. This approach significantly reduces the losses associated with traditional plasmon-induced absorption (PIA) and overcomes the limitations related to performance and polarization sensitivity. Through symmetry breaking, the structure realizes dual-peak perfect absorption (98.1%/98.2%) and ultra-high Q factors (1076/816) in the near-infrared band, enhancing performance two orders over traditional devices. Band structure analysis reveals a quasi-flat band effect, rendering QBIC-controlled peaks insensitive to multi-parameter dispersion. Crucially, the dual peaks exhibit multiplexing polarization: the polarization-insensitive QBIC peak enables stable self-calibrating sensing, while the GMR-driven peak supports dynamic polarization encoding and band switching, enabling multi-parameter sensing and communication multiplexing. Additionally, the system achieves a 15.1 ps group delay, surpassing existing slow light devices. This breakthrough paves the way for polarization-multiplexed communication, environmental sensing, and multifunctional on-chip photonics.
{"title":"Polarization -multiplexing response based on Quasi-BIC in Quasi-flatband","authors":"Ren Guo , Miaofang Zhou , Guangtao Cao , Fan He , Jingfeng Tian , Shuyu Qiao , Hui Yang , Hairong He , Zhiying Zhu , Shaobo Liu , Tao Yu , Min Pan , Hongchao Yi , Gengbiao Lu , Yan Deng , Enduo Gao","doi":"10.1016/j.cjph.2025.12.018","DOIUrl":"10.1016/j.cjph.2025.12.018","url":null,"abstract":"<div><div>Plasmon-induced transparency (PIT) faces limitations in integrated photonics due to low Q factors (<50) and restricted polarization control. This work integrates quasi-bound states in the continuum (QBIC) with guided-mode resonance (GMR), effectively utilizing the material advantages of silicon and silver to achieve the like-plasmon-induced absorption (like-PIA) phenomenon. This approach significantly reduces the losses associated with traditional plasmon-induced absorption (PIA) and overcomes the limitations related to performance and polarization sensitivity. Through symmetry breaking, the structure realizes dual-peak perfect absorption (98.1%/98.2%) and ultra-high Q factors (1076/816) in the near-infrared band, enhancing performance two orders over traditional devices. Band structure analysis reveals a quasi-flat band effect, rendering QBIC-controlled peaks insensitive to multi-parameter dispersion. Crucially, the dual peaks exhibit multiplexing polarization: the polarization-insensitive QBIC peak enables stable self-calibrating sensing, while the GMR-driven peak supports dynamic polarization encoding and band switching, enabling multi-parameter sensing and communication multiplexing. Additionally, the system achieves a 15.1 ps group delay, surpassing existing slow light devices. This breakthrough paves the way for polarization-multiplexed communication, environmental sensing, and multifunctional on-chip photonics.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 225-235"},"PeriodicalIF":4.6,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837437","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}
Pub Date : 2025-12-15DOI: 10.1016/j.cjph.2025.12.021
Feifei Yang , Kailong Zhu , Xinlin Song , Huiping Yin , Jiangxing Chen
Neurons are the basic functional units of the nervous system, and their electrical activities serve as the core carrier for information encoding and transmission. The response patterns of neurons to external stimuli determine the functions and plasticity of neural circuits, and they are also closely related to various neurological diseases. This study aims to systematically investigate the regulatory effects of different types and intensities of external stimuli on the electrical activities of a functional neuron. This study designs a functional neural circuit to capture the signals of external light and the effects of the magnetic field. And then a functional neuron model and corresponding energy function are obtained by applying Kirchhoff’s current law and Helmholtz’s theorem, respectively. Furthermore, the electrical activities of a functional neuron for different types and intensities of external stimuli (light signals and magnetic fields) are investigated by using the nonlinear dynamics analysis method. Moreover, we design an adaptive control method for exploring the self-regulation and self-repairing characteristics of a neuron. Numerical simulation confirmed that the different electrical activities of a functional neuron are activated under diverse external stimuli, and the coherent resonance and stochastic resonance phenomena can occur, respectively, under the noise light signals and noise magnetic fields. This work provides an important theoretical basis for a deeper understanding of the nervous system's response to external stimulus signals.
{"title":"Electrical activity of a functional neuron under diverse external stimuli","authors":"Feifei Yang , Kailong Zhu , Xinlin Song , Huiping Yin , Jiangxing Chen","doi":"10.1016/j.cjph.2025.12.021","DOIUrl":"10.1016/j.cjph.2025.12.021","url":null,"abstract":"<div><div>Neurons are the basic functional units of the nervous system, and their electrical activities serve as the core carrier for information encoding and transmission. The response patterns of neurons to external stimuli determine the functions and plasticity of neural circuits, and they are also closely related to various neurological diseases. This study aims to systematically investigate the regulatory effects of different types and intensities of external stimuli on the electrical activities of a functional neuron. This study designs a functional neural circuit to capture the signals of external light and the effects of the magnetic field. And then a functional neuron model and corresponding energy function are obtained by applying Kirchhoff’s current law and Helmholtz’s theorem, respectively. Furthermore, the electrical activities of a functional neuron for different types and intensities of external stimuli (light signals and magnetic fields) are investigated by using the nonlinear dynamics analysis method. Moreover, we design an adaptive control method for exploring the self-regulation and self-repairing characteristics of a neuron. Numerical simulation confirmed that the different electrical activities of a functional neuron are activated under diverse external stimuli, and the coherent resonance and stochastic resonance phenomena can occur, respectively, under the noise light signals and noise magnetic fields. This work provides an important theoretical basis for a deeper understanding of the nervous system's response to external stimulus signals.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 293-304"},"PeriodicalIF":4.6,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837440","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}
In this paper, a biomimetic membrane-pumping system is presented that can be used to control the yield-stress fluids (Bingham viscoplastic fluid) in an inclined microchannel, with the synergy between external magnetic fields and thermal radiation. The pump works by having synchronized membrane vibrations forming rhythmic compression and expansion cycles which produce controlled flow. The governing equations are solved using a strong mathematical framework that is based on the lubrication theory and non-dimensional analysis, where solutions are validated numerically using the bvp5c high-fidelity collocation version (MATLAB bvp5c). It is found that the combination of the Bingham number (yield stress), the strength of the magnetic field (Hartmann number), and the inclination of the channels predetermines the flow profiles, thermal transport, and shear stress. A parametric analysis indicates that both the yield stress and magnetic field effects substantially inhibit flow while channel orientation can enhance membrane-actuated flow rates. The results show a 47.43 % reduction in flow through the channel with an increase in Hartmann number from 1 to 3; and when a small Bingham number (0.04) is introduced, flow through the channel is reduced by an additional 10.86 %. Conversely, flow through the channel increases by 77.24 % at an angle of π/4. These findings illustrate that the pumping efficiency will be determined by the interaction of the magnetic dampening, yield stress resistance, and gravitational assistive forces acting on the fluid. The irreversibility of thermodynamics is also measured through entropy generation and the Bejan number. Such findings reveal a trade-off between flow and entropy suppression which is operational, and can be used to design transformative paradigms of microfluidic pump optimization, especially in biomedical and thermal management processes that need to handle complex fluids under thermal and magnetic limitations.
{"title":"Entropy generation in membrane-actuated pumping of yield-stress fluids in an inclined microchannel: Influence of heat and magnetic fields","authors":"K.V. Prasad , Hanumesh Vaidya , Mahalingappa Naganur , Rajashekhar V. Choudhari","doi":"10.1016/j.cjph.2025.12.012","DOIUrl":"10.1016/j.cjph.2025.12.012","url":null,"abstract":"<div><div>In this paper, a biomimetic membrane-pumping system is presented that can be used to control the yield-stress fluids (Bingham viscoplastic fluid) in an inclined microchannel, with the synergy between external magnetic fields and thermal radiation. The pump works by having synchronized membrane vibrations forming rhythmic compression and expansion cycles which produce controlled flow. The governing equations are solved using a strong mathematical framework that is based on the lubrication theory and non-dimensional analysis, where solutions are validated numerically using the bvp5c high-fidelity collocation version (MATLAB bvp5c). It is found that the combination of the Bingham number (yield stress), the strength of the magnetic field (Hartmann number), and the inclination of the channels predetermines the flow profiles, thermal transport, and shear stress. A parametric analysis indicates that both the yield stress and magnetic field effects substantially inhibit flow while channel orientation can enhance membrane-actuated flow rates. The results show a 47.43 % reduction in flow through the channel with an increase in Hartmann number from 1 to 3; and when a small Bingham number (0.04) is introduced, flow through the channel is reduced by an additional 10.86 %. Conversely, flow through the channel increases by 77.24 % at an angle of π/4. These findings illustrate that the pumping efficiency will be determined by the interaction of the magnetic dampening, yield stress resistance, and gravitational assistive forces acting on the fluid. The irreversibility of thermodynamics is also measured through entropy generation and the Bejan number. Such findings reveal a trade-off between flow and entropy suppression which is operational, and can be used to design transformative paradigms of microfluidic pump optimization, especially in biomedical and thermal management processes that need to handle complex fluids under thermal and magnetic limitations.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 504-534"},"PeriodicalIF":4.6,"publicationDate":"2025-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145920903","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}
Pub Date : 2025-12-13DOI: 10.1016/j.cjph.2025.12.013
Vinita Goyal, Kushal Sharma
Theoretical analysis of thermo-controlled microfluidic devices provides valuable insights into the mechanism and enhancement of these systems across biomedical diagnostics and chemical applications. Electroosmosis is a fundamental phenomenon that enables the controlled flow of ionic solutions in response to an external electric field, thereby amplifying the pumping flow rate. This study presents an unsteady viscous flow of the Carreau fluid model, whose rheological properties are similar to those of blood in a microchannel, subjected to periodic membrane pumping along with heat transfer. This framework is based on the Navier-Stokes equations, the Poisson equation, along with the velocity slip condition and is further simplified using the lubrication theory and Debye-Hückel linearization. The perturbation series solution method is employed to solve the transformed, dimensionless governing equations together with the corresponding boundary conditions, and the results are presented graphically. The plotted results illustrate that the kinematics of membrane motion generate the transmural pressure, which is controlled by the velocity slip parameter and rheological properties of the fluid. The shear-driven flow leads to a reduction in axial velocity and transmural pressure. Furthermore, mid-channel isotherms are significantly influenced by variations in the Weissenberg and Brinkman numbers.
热控微流控装置的理论分析为这些系统在生物医学诊断和化学应用中的机制和增强提供了有价值的见解。电渗透是一种基本现象，它使离子溶液响应于外电场而控制流动，从而扩大泵送流速。本文提出了一种非定常粘性流动的carcarau流体模型，其流变特性类似于微通道中的血液，在周期性膜泵送的同时进行传热。该框架基于Navier-Stokes方程、泊松方程以及速度滑移条件，并使用润滑理论和debye - h ckel线性化进一步简化。采用摄动级数解法对变换后的无量纲控制方程及其边界条件进行了求解，并以图形形式给出了结果。结果表明，膜的运动产生了跨壁压力，跨壁压力由流体的速度滑移参数和流变特性控制。剪切驱动的流动导致轴向速度和跨壁压力的降低。此外，通道中部等温线受Weissenberg和Brinkman数变化的显著影响。
{"title":"Dynamics of heat transfer and electroosmotic flow in a periodic membrane-induced channel with rheological effects","authors":"Vinita Goyal, Kushal Sharma","doi":"10.1016/j.cjph.2025.12.013","DOIUrl":"10.1016/j.cjph.2025.12.013","url":null,"abstract":"<div><div>Theoretical analysis of thermo-controlled microfluidic devices provides valuable insights into the mechanism and enhancement of these systems across biomedical diagnostics and chemical applications. Electroosmosis is a fundamental phenomenon that enables the controlled flow of ionic solutions in response to an external electric field, thereby amplifying the pumping flow rate. This study presents an unsteady viscous flow of the Carreau fluid model, whose rheological properties are similar to those of blood in a microchannel, subjected to periodic membrane pumping along with heat transfer. This framework is based on the Navier-Stokes equations, the Poisson equation, along with the velocity slip condition and is further simplified using the lubrication theory and Debye-Hückel linearization. The perturbation series solution method is employed to solve the transformed, dimensionless governing equations together with the corresponding boundary conditions, and the results are presented graphically. The plotted results illustrate that the kinematics of membrane motion generate the transmural pressure, which is controlled by the velocity slip parameter and rheological properties of the fluid. The shear-driven flow leads to a reduction in axial velocity and transmural pressure. Furthermore, mid-channel isotherms are significantly influenced by variations in the Weissenberg and Brinkman numbers.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 481-503"},"PeriodicalIF":4.6,"publicationDate":"2025-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145920901","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}
Pub Date : 2025-12-11DOI: 10.1016/j.cjph.2025.12.010
Julija R. Šćepanović , Danica Stojiljković , Zorica M. Jakšić , Ljuba Budinski-Petković , Slobodan B. Vrhovac
The properties of the reversible Random Sequential Adsorption (RSA) of objects of various shapes on a simple three-dimensional (3D) cubic lattice are studied numerically using Monte Carlo simulations. Depositing objects are “lattice animals” made of a certain number of nearest-neighbor sites on a lattice. This work aims to investigate the impact of the geometrical properties of shapes on the temporal evolution of the density θ(t). We analyzed all lattice animals of size and 4. The approach of the density θ(t) to the equilibrium density θ∞ is found to be stretched exponential, , for all lattice animals. The characteristic time scale τ was found to decrease with the probability of desorption according to the power law, . The exponent γ remains unchanged in all shapes of the same size. The parameter A changes depending on the number of different orientations m that the lattice animals can take when placed on a cubic lattice. Orientations of the lattice animal deposited in two randomly chosen places on the lattice are different if one of them cannot be translated into the other. Our findings indicate that the deposition dynamics slows significantly as m decreases. Furthermore, for objects of the same size, the value of parameter β increases with the number of possible orientations m of the shape. The structural heterogeneity in the local relaxation dynamics gives rise to a stretched exponential behavior of the density θ(t) with a lower value of β.
{"title":"Simulation study of reversible random sequential adsorption of lattice animals on a three-dimensional cubic lattice","authors":"Julija R. Šćepanović , Danica Stojiljković , Zorica M. Jakšić , Ljuba Budinski-Petković , Slobodan B. Vrhovac","doi":"10.1016/j.cjph.2025.12.010","DOIUrl":"10.1016/j.cjph.2025.12.010","url":null,"abstract":"<div><div>The properties of the reversible Random Sequential Adsorption (RSA) of objects of various shapes on a simple three-dimensional (3D) cubic lattice are studied numerically using Monte Carlo simulations. Depositing objects are “lattice animals” made of a certain number of nearest-neighbor sites on a lattice. This work aims to investigate the impact of the geometrical properties of shapes on the temporal evolution of the density <em>θ</em>(<em>t</em>). We analyzed all lattice animals of size <span><math><mrow><mi>n</mi><mo>=</mo><mn>1</mn><mo>,</mo><mn>2</mn><mo>,</mo><mn>3</mn><mo>,</mo></mrow></math></span> and 4. The approach of the density <em>θ</em>(<em>t</em>) to the equilibrium density <em>θ</em><sub>∞</sub> is found to be stretched exponential, <span><math><mrow><msub><mi>θ</mi><mi>∞</mi></msub><mo>−</mo><mi>θ</mi><mrow><mo>(</mo><mi>t</mi><mo>)</mo></mrow><mo>∼</mo><mi>exp</mi><mrow><mo>(</mo><mo>−</mo><msup><mrow><mo>(</mo><mi>t</mi><mo>/</mo><mi>τ</mi><mo>)</mo></mrow><mi>β</mi></msup><mo>)</mo></mrow></mrow></math></span>, for all lattice animals. The characteristic time scale <em>τ</em> was found to decrease with the probability of desorption <span><math><msub><mi>P</mi><mtext>des</mtext></msub></math></span> according to the power law, <span><math><mrow><mi>τ</mi><mo>=</mo><mi>A</mi><mspace></mspace><msup><mrow><mo>(</mo><msub><mi>P</mi><mtext>des</mtext></msub><mo>)</mo></mrow><mrow><mo>−</mo><mi>γ</mi></mrow></msup></mrow></math></span>. The exponent <em>γ</em> remains unchanged in all shapes of the same size. The parameter <em>A</em> changes depending on the number of different orientations <em>m</em> that the lattice animals can take when placed on a cubic lattice. Orientations of the lattice animal deposited in two randomly chosen places on the lattice are different if one of them cannot be translated into the other. Our findings indicate that the deposition dynamics slows significantly as <em>m</em> decreases. Furthermore, for objects of the same size, the value of parameter <em>β</em> increases with the number of possible orientations <em>m</em> of the shape. The structural heterogeneity in the local relaxation dynamics gives rise to a stretched exponential behavior of the density <em>θ</em>(<em>t</em>) with a lower value of <em>β</em>.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 254-265"},"PeriodicalIF":4.6,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837355","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}
Pub Date : 2025-12-10DOI: 10.1016/j.cjph.2025.12.009
Anagha A , Ravi Ragoju , Vinit Kumar Tripathi
This study investigates the linear and nonlinear stability of thermal convection in a porous medium saturated by a Jeffrey fluid. The analysis incorporates the combined effects of vertical throughflow, viscous dissipation, and a variable gravity field. The linear stability theory is analyzed using the normal mode technique, while the nonlinear stability threshold is determined using the energy method. The principle of exchange of stabilities is proven, confirming that convection sets in a stationary mode. The resulting eigenvalue problem is solved numerically using the Chebyshev pseudo-spectral method. Four distinct gravity field profiles: linear, parabolic, cubic, and exponential, each decreasing with depth, are examined. A comparative analysis of the critical Rayleigh number is performed to assess the influence of the gravity variation parameter (δ), throughflow parameter (Pe), Jeffrey fluid parameter (λ), and viscous dissipation parameter (Ge). The results demonstrate that the parameters δ and Pe exert a stabilizing influence on the system, whereas Ge and λ have a destabilizing effect. Furthermore, the sensitivity of the system to these parameters is strongly dependent on the gravity profile: the cubic field shows the least sensitivity, while the exponential field exhibits the most pronounced effect. The region of subcritical instability exists only in the presence of vertical throughflow. In its absence, no subcritical instability is observed, even when varying other system parameters.
{"title":"Nonlinear stability analysis of jeffrey fluid in porous medium with vertical throughflow: Effects of variable gravity and viscous dissipation","authors":"Anagha A , Ravi Ragoju , Vinit Kumar Tripathi","doi":"10.1016/j.cjph.2025.12.009","DOIUrl":"10.1016/j.cjph.2025.12.009","url":null,"abstract":"<div><div>This study investigates the linear and nonlinear stability of thermal convection in a porous medium saturated by a Jeffrey fluid. The analysis incorporates the combined effects of vertical throughflow, viscous dissipation, and a variable gravity field. The linear stability theory is analyzed using the normal mode technique, while the nonlinear stability threshold is determined using the energy method. The principle of exchange of stabilities is proven, confirming that convection sets in a stationary mode. The resulting eigenvalue problem is solved numerically using the Chebyshev pseudo-spectral method. Four distinct gravity field profiles: linear, parabolic, cubic, and exponential, each decreasing with depth, are examined. A comparative analysis of the critical Rayleigh number is performed to assess the influence of the gravity variation parameter (<em>δ</em>), throughflow parameter (<em>Pe</em>), Jeffrey fluid parameter (<em>λ</em>), and viscous dissipation parameter (<em>Ge</em>). The results demonstrate that the parameters <em>δ</em> and Pe exert a stabilizing influence on the system, whereas <em>Ge</em> and <em>λ</em> have a destabilizing effect. Furthermore, the sensitivity of the system to these parameters is strongly dependent on the gravity profile: the cubic field shows the least sensitivity, while the exponential field exhibits the most pronounced effect. The region of subcritical instability exists only in the presence of vertical throughflow. In its absence, no subcritical instability is observed, even when varying other system parameters.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"99 ","pages":"Pages 236-253"},"PeriodicalIF":4.6,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837436","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}
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