Chinese Journal of Physics最新文献_第3页

Microgravity influenced unsteady dispersion during magnetic drug targeting in an inclined tumor-stenosed microvessel with slip effects 在具有滑移效应的倾斜肿瘤狭窄微血管中进行磁性药物靶向时受微重力影响的不稳定弥散

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-15 DOI: 10.1016/j.cjph.2024.10.010

Lazaro Revocatus Mashiku , Sachin Shaw

Introduction:

Recent cancer research into microgravity or altered gravity environments has gained attention for its potential to disrupt cancer cell growth and proliferation while reducing the risk of chemoresistance—a major challenge in conventional chemotherapy.

Aim of the study:

Motivated by the emerging applications of microgravity in cancer research, the current study aimed to mathematically investigate the potential of the microgravity-enhanced environment in combination with magnetic drug targeting (MDT) to optimize drug delivery and dispersion.

Methodology:

The particle velocity, including microgravity’s influence in the presence of an external applied magnetic field alongside fluid pressure, was computed analytically while the solute dispersion model was numerically evaluated using the Crank–Nicolson method.

Results:

Findings show that microgravity lowered particle concentration in the tumor, however, improved drug-loaded magnetic nanoparticle properties, and magnetic field strength reveal a positive impact on nanoparticle accumulation. Also, altered stenosis height, inclination angle, slip velocity, and other control parameters such as Peclet number, magnetic-tumor distance, drug source term, elimination, and local skin friction revealed significant differences in particle dispersion behavior before, within, and after the stenosis region.

Conclusion:

Our results suggest potential future therapeutic applications of altered gravity in combination with MDT phenomena to improve drug delivery for noninvasive therapeutic strategies.

研究目的：受微重力在癌症研究中的新兴应用的激励，本研究旨在从数学角度研究微重力增强环境与磁性药物靶向（MDT）相结合优化药物输送和分散的潜力。结果：研究结果表明，微重力降低了粒子在肿瘤中的浓度，但改善了载药磁性纳米粒子的特性，磁场强度对纳米粒子的积累产生了积极影响。此外，改变狭窄高度、倾斜角度、滑移速度和其他控制参数（如佩克莱特数、磁-瘤距离、药物源项、消除和局部皮肤摩擦）也会导致粒子在狭窄区域之前、之内和之后的分散行为出现显著差异。

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引用次数: 0

Cilia-assisted flow of electrically conducting micropolar fluid in a heated curved channel under Soret and Dufour effects 在索雷特和杜富尔效应作用下，纤毛辅助导电微极性流体在加热弯曲通道中流动

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-15 DOI: 10.1016/j.cjph.2024.10.018

M.S. Arslan, Z. Abbas, M.Y. Rafiq

Cilia flow plays a crucial role in biological systems such as the movement of mucus in the respiratory tract, circulation of cerebrospinal fluid in the brain, and propulsion of sperm cells. Understanding the cilia flow of viscous fluids is essential for elucidating the biomechanics of these processes and their implications for health and disease. Motivated by such numerous biomedical applications, this article aims to exhibit the influence of heat and mass transfer on the ciliary flow of an electrical conducting micropolar fluid in a curved channel. The energy and concentration equations are modulated with viscous dissipation, Soret, and Dufour effects. The constitutive equations are simplified by the lubrication approximation and then solved numerically using the implicit finite difference method (FDM). Results for velocity, pumping phenomenon, concentration, thermal field, rate of heat transfer, streamlines, skin friction coefficient, Nusselt number, and Sherwood number are analyzed subject to pertinent parameters. The study reveals that velocity is enhanced via both the micropolar parameter and curvature parameter. Temperature enhances for larger values of Dufour and Brickman numbers. Furthermore, the radial magnetic field plays a resistive role in the trapped bolus. The findings presented in this study should prove beneficial for researchers in the domains of medicine, engineering, science, and fluid mechanics. Further, it is found that the micropolar fluid model is more suitable for biofluids like blood.

纤毛流动在生物系统中起着至关重要的作用，例如呼吸道中粘液的流动、大脑中脑脊液的循环以及精子细胞的推进。了解粘性流体的纤毛流动对于阐明这些过程的生物力学及其对健康和疾病的影响至关重要。在如此众多的生物医学应用的推动下，本文旨在展示热量和质量传递对导电微极性流体在弯曲通道中的纤毛流动的影响。能量和浓度方程受到粘性耗散、索雷特和杜福尔效应的影响。通过润滑近似简化了构成方程，然后使用隐式有限差分法（FDM）进行数值求解。根据相关参数分析了速度、泵送现象、浓度、热场、传热速率、流线、表皮摩擦系数、努塞尔特数和舍伍德数的结果。研究结果表明，速度通过微波参数和曲率参数得到增强。当杜富尔数和布里克曼数的值越大，温度越高。此外，径向磁场在被困漩涡中起着阻力作用。本研究的发现将对医学、工程学、科学和流体力学领域的研究人员大有裨益。此外，研究还发现微极性流体模型更适用于血液等生物流体。

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引用次数: 0

Silicon nitride directional coupler-based polarization beam splitter utilizing shallow ridge waveguides for improved fabrication tolerance 基于氮化硅定向耦合器的偏振分束器，利用浅脊波导提高制造公差

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-13 DOI: 10.1016/j.cjph.2024.10.014

Po-Hsiang Chiu , Yi-Jia Huang , Yong-Jun Chen , Zi-Xuan Xu , Hsing-Hsiang Wang , Wen-Hsien Huang , Chun-Ta Wang

This study presents the design and fabrication of a silicon nitride (Si₃N₄) asymmetrical directional coupler (DC)-based polarization beam splitter (PBS) utilizing a shallow ridge waveguide structure. The use of Si₃N₄ with a moderate refractive index contrast and the design of a shallow ridge waveguide enables the DC structure to have a wider coupling gap of approximately 600 nm, which can be readily achieved with standard I-line lithography. The simulation results indicate that the polarization splitting is highly efficient with minimal insertion loss. This is corroborated by the experimental measurements, which show consistent broadband performance. The fabricated polarization beam splitter (PBS) exhibits a high polarization extinction ratio (PER) of over 20 dB for both transverse electric (TE) and transverse magnetic (TM) modes across a broad bandwidth of 120 nm (1500–1620 nm). This work demonstrates the potential of shallow ridge Si₃N₄ waveguides to enhance the fabrication tolerance and performance of integrated photonic devices.

本研究介绍了利用浅脊波导结构设计和制造基于氮化硅（Si3N4）的非对称定向耦合器（DC）的偏振分束器（PBS）。使用折射率对比适中的 Si3N4 和设计浅脊波导，使 DC 结构具有更宽的耦合间隙（约 600 nm），这可以通过标准 I 线光刻轻松实现。模拟结果表明，极化分路效率很高，插入损耗极小。实验测量也证实了这一点，并显示出一致的宽带性能。制作的偏振分束器 (PBS) 在 120 纳米（1500-1620 纳米）的宽带宽范围内，横向电（TE）和横向磁（TM）模式的偏振消光比 (PER) 均超过 20 dB。这项工作证明了浅脊 Si3N4 波导在提高集成光子器件的制造容差和性能方面的潜力。

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引用次数: 0

Optical parameter inversion of thin films based on angular reflectance spectroscopy 基于角反射光谱的薄膜光学参数反演

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-13 DOI: 10.1016/j.cjph.2024.10.013

Jian-Xiao Liu , Ling-Hui Meng , Shi-Yao Chong , Jiong-Ju Hao , Hong-Wei Yang

This article proposes a method for obtaining the refractive index and thickness of thin films based on reflectivity at different angles combined with optimization algorithms. This method has high computational accuracy for both high absorption films (such as aluminum films, gold films, etc.) and low absorption films (such as MgF₂ films). Since this study did not adopt the inversion scheme of refractive index dispersion equation fitting, it can be used for optical constant inversion in the case of unknown composition of coating materials. The results indicate that this method can simultaneously obtain high-precision information on the complex refractive index and film thickness of the coating material on the substrate. The calculation example achieved a thickness inversion error of 0.165 % for a 2nm metal aluminum film layer and 0.3303 % for a 150 nm MgF₂ transparent film layer. Therefore, this study may provide further guidance for high absorption and measurement of the complex refractive index and thickness of transparent films.

本文提出了一种基于不同角度反射率并结合优化算法获得薄膜折射率和厚度的方法。该方法对高吸收率薄膜（如铝膜、金膜等）和低吸收率薄膜（如 MgF2 薄膜）都有很高的计算精度。由于该研究没有采用折射率色散方程拟合的反演方案，因此可用于涂层材料成分未知情况下的光学常数反演。结果表明，该方法可以同时获得基底上涂层材料的复折射率和薄膜厚度的高精度信息。计算实例中，2 纳米金属铝膜层的厚度反演误差为 0.165%，150 纳米 MgF2 透明膜层的厚度反演误差为 0.3303%。因此，这项研究可为高吸收和测量透明薄膜的复折射率和厚度提供进一步指导。

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引用次数: 0

Understanding small neutrino mass and its implication 了解小中微子质量及其影响

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-11 DOI: 10.1016/j.cjph.2024.10.009

Hsiang-nan Li

We have derived previously the relations between the neutrino masses and mixing angles in a dispersive analysis on the mixing of neutral leptonic states. The only involved assumption is that the electroweak symmetry of the Standard Model (SM) is restored at a high energy scale in some new physics scenario, which diminishes the box diagrams responsible for the mixing. Here we include corrections to the analysis up to three loops, arising from exchanges of additional neutral and charged scalars in the electroweak symmetric phase. The solution to the dispersion relation for the

μ^{-} e^{+}

-

μ^{+} e^{-}

mixing generates a typical neutrino mass

m_{ν} \sim O (1) eV

in the SM unambiguously. The solution also favors the normal ordering of the neutrino masses over the inverted one, and links the large electroweak symmetry restoration, i.e., new physics scale to the small neutrino mass.

我们之前在对中性轻子态混合的色散分析中推导出了中微子质量和混合角之间的关系。其中唯一涉及的假设是，标准模型（SM）的电弱对称性在某种新物理情景下的高能量尺度上得到了恢复，从而减少了负责混合的盒图。在这里，我们把电弱对称相中额外的中性和带电标量的交换引起的三环以内的分析修正包括在内。μ-e+-μ+e-混合的色散关系解明确地产生了SM中典型的中微子质量mν∼O(1)eV。该方案还倾向于中微子质量的正常排序而不是倒序，并将大的电弱对称性恢复，即新物理尺度与小的中微子质量联系起来。

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引用次数: 0

Probing the two-electron-interaction-induced three new hopping processes in a double quantum-dot system revealed by finite-frequency shot noise 探测有限频射噪声揭示的双量子点系统中双电子相互作用诱导的三个新跳跃过程

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-11 DOI: 10.1016/j.cjph.2024.10.007

Hai-Bin Xue, Xing-Yun Lü, Bin Chen, Jian-Bin Chen, Li-Li Xing

In the serially coupled double quantum dot (DQD) system, the two-electron-interaction-induced electron hopping processes and spin-exchange hopping processes play a crucial role in manipulating the spin degree of freedom of localized electrons in the DQD system. Consequently, from the perspective of electron transport, how to detect the new hopping processes induced by the two-electron interaction has become an increasingly important issue. Here, the influences of the three new hopping processes predicted by the generalized Hubbard model on the finite-frequency shot noise of electron transport through a serially coupled DQD system are studied. It is demonstrated that in the energy-level detuning case the criterion for the existence of the electron-occupation-modulated hopping processes is that the maximum number of peaks and dips of the finite-frequency shot noise equals eight while in the energy-level alignment case the criteria for the existence of the two-electron-interaction-induced three new hopping processes, and the antiparallel-electron-spin-exchange hopping and electron-pair hopping processes, and the electron-occupation-modulated hopping processes are that the maximum numbers of peaks and dips equal eight, seven, and six, respectively. Therefore, these results provide an alternative way to detect the three new hopping processes predicted by the generalized Hubbard model in the serially coupled DQD system.

在串联耦合双量子点（DQD）体系中，双电子相互作用诱导的电子跳变过程和自旋交换跳变过程在操纵DQD体系中局域电子的自旋自由度方面起着至关重要的作用。因此，从电子传输的角度来看，如何探测双电子相互作用诱导的新跳变过程已成为一个越来越重要的问题。本文研究了广义哈伯德模型预测的三种新跳变过程对电子通过串联耦合 DQD 系统传输的有限频率射出噪声的影响。结果表明，在能级失谐情况下，电子占位调制跳变过程存在的标准是有限频率射出噪声的最大峰值和骤降数等于 8，而在能级对齐情况下，双电子相互作用诱导的三个新跳变过程存在的标准是：电子占位调制跳变过程的最大峰值和骤降数等于 8，而在能级对齐情况下，双电子相互作用诱导的三个新跳变过程存在的标准是：电子占位调制跳变过程的最大峰值和骤降数等于 8、和反平行电子自旋交换跳变过程、电子对跳变过程以及电子占位调制跳变过程存在的标准是峰值和骤降的最大数量分别等于 8、7 和 6。因此，这些结果为探测串联耦合 DQD 系统中广义哈伯德模型预测的三种新的跳变过程提供了另一种方法。

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引用次数: 0

Dynamics of a stochastic impulsive vegetation system with regime switching 具有系统切换的随机脉冲植被系统的动力学特性

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-10 DOI: 10.1016/j.cjph.2024.09.043

He Liu , Chuanjun Dai , Hengguo Yu , Yi Wang , Qing Guo , Jianbing Li , Min Zhao

This paper describes an analytical and numerical investigation of a novel stochastic impulsive vegetation system with regime switching. Impulsive control, white noise, regime switching, and rainfall are modeled as crucial factors to simulate natural ecological phenomena, with the aim to explore the effects of those factors on the dynamics of vegetation system. Dynamics of the system, including the existence and uniqueness of global positive solutions, extinction, non-persistence in the mean, weak persistence and stochastic persistence, are investigated firstly under the effects of impulsive control and regime switching. For system without impulsive perturbations, we investigate the existence and uniqueness of the stationary distribution for the system, demonstrating that the vegetation can survive forever. Using a sophisticated sensitivity analysis technique, it is found that the vegetation biomass is highly sensitive to the rainfall but least sensitive to the saturation constant of the vegetation consumption. Our numerical results reveal that either the reduced rainfall or increased environmental disturbance can tip the balance of vegetation system, but this relationship can be effectively regulated by implementing impulsive control schemes. Additionally, it is observed that system at high-level rainfall may be detrimental to maintain the balance of vegetation, but regime switching in rainfall patterns can balance different states of vegetation and provide higher survival chance for vegetation. Significantly, it emphasizes that the persistence-extinction behaviors of the vegetation are more sensitive to the change of regime switching, indicating that the proper and general environmental disturbances is beneficial to maintain dynamic balance of vegetation system. These findings may provide new insights into the complex vegetation system dynamics.

本文描述了对一种新型随机冲动植被系统的分析和数值研究。将脉冲控制、白噪声、制度切换和降雨作为模拟自然生态现象的关键因素建模，旨在探讨这些因素对植被系统动力学的影响。首先研究了冲动控制和制度转换影响下的系统动力学，包括全局正解的存在性和唯一性、消亡、均值不持续、弱持续和随机持续。对于无脉冲扰动的系统，我们研究了系统静态分布的存在性和唯一性，证明植被可以永久生存。利用复杂的敏感性分析技术，我们发现植被生物量对降雨量高度敏感，但对植被消耗饱和常数的敏感性最低。我们的数值结果表明，降雨量减少或环境干扰增加都会破坏植被系统的平衡，但这种关系可以通过实施脉冲控制方案得到有效调节。此外，我们还观察到，高降雨量系统可能不利于维持植被平衡，但降雨模式的制度转换可以平衡植被的不同状态，为植被提供更高的存活机会。值得注意的是，该研究强调植被的存活-消亡行为对雨量变化更为敏感，表明适当的一般性环境干扰有利于维持植被系统的动态平衡。这些发现可为复杂的植被系统动力学提供新的见解。

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引用次数: 0

Computational evaluating on the role of sac centerline length on hemorrhage risk of anterior cerebral artery with saccular aneurysm 计算评估囊中心线长度对大脑前动脉囊状动脉瘤出血风险的影响

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-09 DOI: 10.1016/j.cjph.2024.10.006

Qingquan Zhang , Zhenjin Su , Zeshang Guo

The present article investigates geometrical features of an aneurysm, particularly the sac centerline length (SCL), in determining the hemodynamic environment within the aneurysm for evaluation of the hemorrhage risk. Indeed, understanding how these geometric characteristics influence blood flow patterns is essential for assessing rupture risk and optimizing treatment strategies. Computational fluid dynamic is used to perform computational modeling of the blood hemodynamic in Anterior Communicating Artery (ACA) cases. Wall shear stress (WSS), Oscillatory Shear Index (OSI) and pressure over sac surface are investigated and compared for selected saccular aneurysm to evaluate risk of aneurysm rupture when sac centerline length is varied. Comparison of the results show that the inverse relationship between sac centerline length and these key hemodynamic parameters (OSI, velocity, WSS) underscores the importance of geometrical factors in assessing aneurysm rupture risk. Longer sac centerline lengths appear to be associated with more stable flow dynamics and reduced mechanical stress, while shorter sac lengths correlate with more disturbed and high-stress conditions.

本文研究了动脉瘤的几何特征，尤其是囊中心线长度（SCL），以确定动脉瘤内的血流动力学环境，从而评估出血风险。事实上，了解这些几何特征如何影响血流模式对于评估破裂风险和优化治疗策略至关重要。计算流体动力学用于对前沟通动脉（ACA）病例的血液动力学进行计算建模。研究并比较了选定囊状动脉瘤的壁剪应力（WSS）、振荡剪切指数（OSI）和囊表面压力，以评估囊中心线长度变化时动脉瘤破裂的风险。比较结果表明，囊中心线长度与这些关键血液动力学参数（OSI、速度、WSS）之间的反比关系强调了几何因素在评估动脉瘤破裂风险中的重要性。较长的囊中心线长度似乎与较稳定的血流动力学和较低的机械应力有关，而较短的囊长度则与较紊乱和高应力条件有关。

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引用次数: 0

Exploring certain nonlinear localized modes in an anisotropic ferromagnet with biquadratic interaction using quasi-discrete approximation 用准离散近似法探索具有双四边形相互作用的各向异性铁磁体中的某些非线性局部模式

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-09 DOI: 10.1016/j.cjph.2024.09.036

S. Suganya , B. Srividya , A. Prabhu

We present an analytical work on nonlinear localized modes in an anisotropic ferromagnet with added biquadratic interaction. Within the framework of quasi-discrete multiple scale approximation, it is found that the dynamics of the system is associated with the nonlinear Schrödinger (NLS) equation. The effect of anisotropic and biquadratic interactions on the nature of the linear dispersion curve is discussed. The criteria for the existence of bright and dark solitons are explored. Different classes of soliton solutions are constructed using the Hirota bilinearization method. Also, it is noted that the system and soliton parameters significantly modify the characteristics of the solitons by the inclusion of highly nonlinear invariant biquadratic interaction.

我们介绍了关于各向异性铁磁体中的非线性局部模式的分析工作，该铁磁体具有附加的双四次方相互作用。在准离散多尺度近似的框架内，我们发现该系统的动力学与非线性薛定谔方程（NLS）有关。讨论了各向异性和双四性相互作用对线性分散曲线性质的影响。探讨了亮孤子和暗孤子存在的标准。使用 Hirota 双线性化方法构建了不同类别的孤子解。此外，我们还注意到系统和孤子参数通过加入高度非线性不变的双二次方相互作用而极大地改变了孤子的特性。

引用次数: 0

Analysis of the multi-term fractional Bateman equations in radioactive decay by means of Mikusiński algebraic calculus 用米库辛斯基代数微积分分析放射性衰变中的多期分数贝特曼方程

IF 4.6 2区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Chinese Journal of Physics

Pub Date : 2024-10-09 DOI: 10.1016/j.cjph.2024.10.002

Marc Jornet

Fractional Bateman equations model the concentrations of nuclear species through a radioactive decay chain, by considering non-Markovian behavior. Cruz-López and Espinosa-Paredes (Nuclear Engineering and Technology, 2022) solved the mathematical problem with a single memory coefficient, based on the Laplace-transform technique. Cruz-López, Espinosa-Paredes and François (Computer Physics Communications, 2022) extended the analysis to several fractional orders, with Laplace transforms and series expansions checked by induction. In this paper, we solve such a case of distinct memory effects, via the more general method of Mikusiński operational calculus. We do not distinguish between equal and different decay rates. Multivariate Mittag-Leffler functions appear in the closed-form expression.

分数贝特曼方程通过考虑非马尔可夫行为，对放射性衰变链中的核物种浓度进行建模。克鲁兹-洛佩斯和埃斯皮诺萨-帕雷德斯（核工程与技术，2022 年）基于拉普拉斯变换技术，用单一记忆系数解决了这一数学问题。克鲁兹-洛佩斯、埃斯皮诺萨-帕雷德斯和弗朗索瓦（《计算机物理通讯》，2022 年）将分析扩展到多个分数阶，通过归纳法检验拉普拉斯变换和数列展开。在本文中，我们通过米库辛斯基运算微积分的更一般方法，解决了这种不同记忆效应的情况。我们不区分相同和不同的衰减率。多变量米塔格-勒弗勒函数出现在闭式表达式中。

引用次数: 0