Chinese Journal of Physics最新文献_第5页

Influence of bleb formation on intracranial aneurysm hemodynamics: a patient-specific CFD study 气泡形成对颅内动脉瘤血流动力学的影响：一项针对患者的CFD研究

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

Chinese Journal of Physics

Pub Date : 2025-12-10 DOI: 10.1016/j.cjph.2025.12.011

Li Song , Peng Du , Erhao Bao

Intracranial aneurysms with secondary bleb formation are considered to have an elevated risk of rupture due to localized geometric and hemodynamic instabilities. In this study, we perform a comparative computational fluid dynamics (CFD) analysis on five patient-specific aneurysm geometries, examining pre- and post-bleb configurations to evaluate hemodynamic changes associated with bleb development. Key metrics including wall shear stress (WSS), sac wall pressure, and intra-aneurysmal velocity were analyzed at peak systolic time points while oscillatory shear index (OSI) is obtained vial whole cardiac cycle. Results indicate that bleb formation introduces localized flow disturbances and hemodynamic variability, with case-dependent effects. Quantitatively, bleb regions exhibited up to a 36% reduction in mean WSS (e.g., Case E: 13.3 Pa → 9.8 Pa) and up to a 4-fold increase in minimum WSS (e.g., Case C: 0.21 Pa → 0.72 Pa in the bleb), reflecting strong spatial heterogeneity in shear loading. Despite these hemodynamic changes, the vessel wall in bleb regions becomes thinner and structurally weaker, reducing its resistance to blood pressure and thereby increasing rupture susceptibility. These findings emphasize the importance of multi-parametric hemodynamic evaluation—particularly WSS magnitude, OSI distribution, and flow patterns—in understanding bleb-induced changes in aneurysm stability. The study underscores the need for individualized risk assessment strategies that go beyond morphological classification alone.

由于局部几何和血流动力学不稳定，颅内动脉瘤伴继发性气泡形成被认为具有较高的破裂风险。在这项研究中，我们对五种患者特定的动脉瘤几何形状进行了比较计算流体动力学（CFD）分析，检查了起泡前和起泡后的配置，以评估与气泡发展相关的血流动力学变化。主要指标包括收缩峰值时的壁剪切应力（WSS）、囊壁压力和动脉瘤内速度，并获得整个心脏周期内的振荡剪切指数（OSI）。结果表明，气泡的形成会引起局部的血流紊乱和血流动力学变异性，并具有病例依赖性。从数量上看，气泡区域的平均WSS减少了36%（例如，病例E: 13.3 Pa→9.8 Pa），最小WSS增加了4倍（例如，病例C: 0.21 Pa→0.72 Pa），反映了剪切载荷的强烈空间异质性。尽管有这些血流动力学变化，但水泡区域的血管壁变薄，结构变弱，降低了其对血压的抵抗力，从而增加了破裂的易感性。这些发现强调了多参数血流动力学评估的重要性，特别是WSS大小、OSI分布和血流模式，以了解气泡引起的动脉瘤稳定性变化。该研究强调需要个性化的风险评估策略，而不仅仅是形态学分类。

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引用次数: 0

Realistic modeling of neutron star structures with linear and non-linear matter-curvature coupling in f(R,Lm,T)− gravity using SLy4, Togashi, and Walecka equation of state 利用sl4、Togashi和Walecka状态方程模拟f(R,Lm，T)−重力下具有线性和非线性物质曲率耦合的中子星结构

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

Chinese Journal of Physics

Pub Date : 2025-12-09 DOI: 10.1016/j.cjph.2025.12.004

N. Priyobarta , Ksh. Newton Singh , S.K. Maurya , B. Mishra

We are presenting realistic models of neutron star supported by the SLy4, Togashi, and Walecka equation of states (EoS) in

f (R, L_{m}, T) -

gravity. Considering both linear (i.e.,

f (R, L_{m}, T) = R + β T + 2 γ L_{m}

) and non-linear matter-curvature models (i.e.,

f (R, L_{m}, T) = R + α T L_{m}

), we derived modified TOV equations for each model and solved them numerically. The strength of the matter-curvature coupling is scaled by the coupling constant α in non-linear and (β, γ) in linear interactions. In the non-linear and linear couplings, only with the Walecka EoS can generate maximum masses above 2.5M_⊙ which can accommodate the higher mass neutron stars in the mass-gap. All the EoS became more stiff for (α, β, γ) < 0 that produce more maximum masses. The causality is checked by the density range which is about 2 × 10¹⁵g/cm³ for Togashi, 3.06 × 10¹⁵g/cm³ for SLy4 and 5.08 × 10¹⁵g/cm³ for Walecka EoS. The larger causality density range in Walecka EoS makes it more stable while neutron stars are subjected to radial perturbation. Under small radial oscillation, all the EoS can hold more M_max by increasing the coupling strength (α, β, γ) < 0. The gravitational redshift in all the models is below 0.4, which is far below the Buchdahl redshift limit, i.e.,  ≤ 2. At the end, we used the GW170817 constraints to validate the results with observational values to constraint the predicted radii of the known GWs and pulsars.

我们提出了由f(R,Lm，T)−重力下的sl4， Togashi和Walecka状态方程（EoS）支持的中子星现实模型。考虑线性（即f(R,Lm，T)=R+βT+2γLm）和非线性物质曲率模型（即f(R,Lm，T)=R+αTLm），分别推导了修正的TOV方程，并对其进行了数值求解。物质-曲率耦合的强度由非线性耦合常数α和线性耦合常数（β, γ）来标度。在非线性和线性耦合中，只有Walecka EoS才能产生大于2.5M⊙的最大质量，这可以容纳质量间隙中较大质量的中子星。当（α, β, γ） <； 0产生更多的最大质量时，所有的EoS都变得更硬。通过密度范围检验因果关系，Togashi的密度范围约为2 × 1015g/cm3， SLy4的密度范围约为3.06 × 1015g/cm3， Walecka EoS的密度范围约为5.08 × 1015g/cm3。Walecka EoS中较大的因果密度范围使其在中子星受到径向摄动时更加稳定。在径向振荡较小的情况下，通过增加耦合强度（α, β, γ） <； 0，所有的EoS都能保持更大的Mmax。所有模型的引力红移均小于0.4，远低于Buchdahl红移极限 ≤ 2。最后，我们利用GW170817约束对结果进行了验证，并结合观测值对已知GWs和脉冲星的预测半径进行了约束。

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引用次数: 0

Patient-specific deep learning reduced-order model of blood hemodynamic indices in thoracic aortic aneurysms via dynamic mode decomposition 基于动态模态分解的胸主动脉瘤血流动力学指标的深度学习降阶模型

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

Chinese Journal of Physics

Pub Date : 2025-12-08 DOI: 10.1016/j.cjph.2025.11.031

Nadia Ghezaiel Hammouda , Joy Djuansjah , Ali B M Ali , As’ad Alizadeh , Muntadher Abed Hussein , Narinderjit Singh Sawaran Singh , Khalil Hajlaoui , Walid Aich

This study proposes a data-driven reduced order modeling (ROM) framework for accurately predicting unsteady wall shear stress (WSS) distributions in thoracic aortic aneurysms (TAA). High-fidelity computational fluid dynamics (CFD) simulations of pulsatile blood flow were used to generate a snapshot library of WSS fields. Dynamic mode decomposition (DMD) was employed to extract dominant spatiotemporal flow structures and reduce the system dimensionality. These DMD time coefficients were then used to train a deep learning architecture combining convolutional neural networks (CNNs), squeeze-and-excitation (SE) attention blocks, and long short-term memory (LSTM) units. The proposed attention-enhanced CNN-LSTM model accurately forecasts the temporal evolution of DMD coefficients, enabling full-field WSS reconstruction at unseen time instances. Quantitative evaluations demonstrate strong agreement with ground truth CFD results, with pointwise relative errors remaining below 5 % on most regions of the aneurysm surface. Modal and gradient-based analyses reveal that high WSS gradients and flow complexity near the dome and outlet regions contribute most to prediction errors. Overall, the method offers an efficient and accurate surrogate for simulating complex hemodynamics in patient-specific geometries, making it suitable for real-time clinical evaluation and treatment planning.

本研究提出了一个数据驱动的降阶模型（ROM）框架，用于准确预测胸主动脉瘤（TAA）的非定常壁剪应力（WSS）分布。采用高保真计算流体动力学（CFD）模拟脉动血流，生成WSS场的快照库。采用动态模态分解（DMD）提取优势时空流结构，降低系统维数。然后使用这些DMD时间系数来训练一个深度学习架构，该架构结合了卷积神经网络（cnn）、挤压和激励（SE）注意力块和长短期记忆（LSTM）单元。本文提出的注意力增强CNN-LSTM模型准确预测了DMD系数的时间演变，实现了在未知时间实例下的全场WSS重建。定量评估结果与地面真实CFD结果非常吻合，在动脉瘤表面的大多数区域，点相对误差保持在5%以下。基于模态和梯度的分析表明，高WSS梯度和靠近穹顶和出口区域的流动复杂性是导致预测误差的主要原因。总的来说，该方法为模拟患者特定几何形状的复杂血流动力学提供了一种高效、准确的替代方法，适用于实时临床评估和治疗计划。

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引用次数: 0

Star formation efficiency of molecular clouds: In terms of the cloud collapsing time and magnetic braking time 分子云的恒星形成效率：以云坍缩时间和磁制动时间计算

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

Chinese Journal of Physics

Pub Date : 2025-12-06 DOI: 10.1016/j.cjph.2025.11.034

Gemechu Muleta Kumssa

This paper aims to investigate the star formation efficiency of molecular cloud cores that are affected by gravitational forces, turbulence, magnetization, and rotation. It intends to include the impacts of magnetic tension and assess the restoring force it provides. By applying the standard equations that dictate magnetohydrodynamic collapse within a rotating context, the study will ascertain the time necessary for the cloud to collapse. Following this, a mathematical model for star formation efficiency is formulated, incorporating the collapse time while also taking into account the effects of magnetic tension. The function of the magnetic field is particularly complex, operating in two distinct roles. On one side, the tension within the magnetic field lines aids the inward movement of matter towards the central core, thus facilitating mass accumulation. On the other hand, the magnetic pressure opposes gravity, reducing mass in fall rate. This complex interaction ultimately leads to a decrease in star formation efficiency, as indicated by the findings of this study.

本文旨在研究重力、湍流、磁化和旋转对分子云核心恒星形成效率的影响。它打算包括磁张力的影响，并评估它提供的恢复力。通过应用在旋转环境中指示磁流体力学坍缩的标准方程，该研究将确定云坍缩所需的时间。在此基础上，建立了恒星形成效率的数学模型，其中考虑了坍缩时间，同时也考虑了磁张力的影响。磁场的功能特别复杂，有两种不同的作用。一方面，磁力线内的张力有助于物质向内运动，从而促进质量积累。另一方面，磁压力与重力相反，降低了质量下降的速度。这种复杂的相互作用最终导致恒星形成效率的降低，正如本研究的发现所表明的那样。

引用次数: 0

Phonon confinement effect on breathing vibrations of monolayer and few-layer metal dichalcogenides 声子约束对单层和少层金属二硫族化合物呼吸振动的影响

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

Chinese Journal of Physics

Pub Date : 2025-12-05 DOI: 10.1016/j.cjph.2025.12.006

Duy Van Pham , Yi-Xuan Lu , Yu-Hsiang Wang , Carlo C.Sta. Maria , Ming-Hsien Lee , Chien-Chih Lai , Rupesh S. Devan , Yuan-Ron Ma

Two-dimensional 4H-SnS₂ single crystals of several square millimeters were grown using chemical vapor transport method. A bulk 4H-SnS₂ can be easily exfoliated into few-layer 4H-SnS₂ using mechanical exfoliation technique. Few-layer and multilayer 4H-SnS₂ of 3, 8, 13, 27, 43, and 71 monolayers were stably obtained in ambient. The Raman spectra of few-layer and multilayer 4H-SnS₂ reveal a single dominant A_1g Raman mode. The A_1g Raman mode of few-layer 4H-SnS₂ is redshifted and broadened with reduced layer number, indicating that the phonon confinement effect is layer-dependent. The Raman tensor of the few-layer 4H-SnS₂ can be fixed with the phonon confinement effect. This effect also significantly influences the thermodynamic properties of few-layer 4H-SnS₂. The results provide valuable insights for the design of next-generation photonic and thermoelectric devices based on 4H-SnS₂.

采用化学气相输运法制备了几平方毫米大小的二维4H-SnS2单晶。采用机械剥离技术，块状的4H-SnS2可以很容易地剥离成几层的4H-SnS2。在室温条件下稳定制备了3、8、13、27、43和71单层的少层和多层4H-SnS2。少层和多层4H-SnS2的拉曼光谱显示单一主导的A1g拉曼模式。少层4H-SnS2的A1g拉曼模式随着层数的减少而红移和展宽，表明声子约束效应是层相关的。利用声子约束效应可以固定少层4H-SnS2的拉曼张量。这一效应也显著影响了少层4H-SnS2的热力学性质。研究结果为基于4H-SnS2的下一代光子和热电器件的设计提供了有价值的见解。

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引用次数: 0

String shoving and flavor rope effects on single and double-strange resonance productions in pp collisions at s = 13 TeV s = 13 TeV下pp碰撞中单、双奇异共振的推弦效应和风味绳效应

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

Chinese Journal of Physics

Pub Date : 2025-12-04 DOI: 10.1016/j.cjph.2025.11.030

Uzma Tabassam, Bisma Kabir

We have investigated the invariant differential yield of resonance states of

Σ {(1385)}^{* +}

+

\bar{Σ} {(1385)}^{* -}

and Ξ(1530)⁰+

\bar{Ξ} {(1530)}^{0}

baryons in pp collisions at

\sqrt{s}

= 13 TeV for different multiplicity classes within the mid rapidity region of |y| < 0.5. For particle production, the PYTHIA8312 event generator is used. The model was tuned to include the flavor rope effects and string shoving mechanisms to enhance the production of hyperons and baryons. It was observed that for the higher multiplicity classes the MC predictions are close to the ALICE experimental results, whereas for the low multiplicity classes, small deviations were observed. It was observed that, in pp collisions due to absence of phase space the MC predictions do not fully agree with the ALICE experimental data. The observed deviations could be due to the limitations in the modeling and limited rope haronization and shoving effects. Strangeness enhancement was observed by analyzing the baryon to meson ratio. The ALICE and MC simulation data is fitted with the Tsallis distribution function to study the effective temperature T_eff at freeze out stage of system in different multiplicity classes. The extracted Tsallis parameters do agree well with the literature values resulting in the observation that the high multiplicity events exhibit greater thermalization. Additionally, we observed the strong radial and rescattering effects in the system.

我们研究了在s = 13 TeV的pp碰撞中，在|y| <； 0.5的中速区内，不同多重等级的Σ(1385)*+ + Σ¯(1385)* -和Ξ（1530）0+ Ξ¯（1530）0重子的共振态的不变差分产率。对于粒子生成，使用PYTHIA8312事件生成器。该模型被调整为包括风味绳效应和弦推机制，以提高超子和重子的产生。结果表明，对于高多重分类，MC预测与ALICE实验结果接近，而对于低多重分类，MC预测与ALICE实验结果偏差较小。观察到，在pp碰撞中，由于缺乏相空间，MC预测与ALICE实验数据不完全一致。观察到的偏差可能是由于建模的局限性和有限的绳索协调和推挤效应。通过分析重子与介子的比值，观察到奇异度增强。采用Tsallis分布函数对ALICE和MC模拟数据进行拟合，研究了不同多重等级下系统冻出阶段的有效温度Teff。提取的Tsallis参数与文献值吻合较好，因此观察到高多重度事件表现出更大的热化。此外，我们还观察到系统中存在较强的径向和重散射效应。

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引用次数: 0

Global stability analysis on the onset of convection in an inclined porous layer with Casson fluid under the effect of viscous dissipation and along-slope buoyancy induced throughflow 粘性耗散和顺坡浮力诱导的通流作用下卡森流体倾斜多孔层对流开始的全局稳定性分析

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

Chinese Journal of Physics

Pub Date : 2025-12-03 DOI: 10.1016/j.cjph.2025.12.001

Jacqueline Do Rosario e Souza , Bhagya Mathapati , Ravi Ragoju , Dhananjay Yadav

This study investigates the onset of thermal convection within a Casson fluid-saturated, inclined porous layer and accounting for the effect of viscous dissipation and along-slope buoyancy induced throughflow. The system consists of two parallel plates with an angle of inclination, ϕ from the horizontal and is analyzed using linear and nonlinear stability characteristics. Darcy law is used to describe the flow. The governing equations, including continuity, momentum, and energy balances, are first non-dimensionalized to introduce key parameters such as the Darcy–Rayleigh number, the Gebhart number, inclination angle, and the Casson fluid index. Linear stability analysis of disturbances is conducted by applying a normal mode technique. To complement the linear analysis, nonlinear stability is examined using the energy method, where an energy functional is constructed to determine thresholds for global nonlinear stability. The boundary eigenvalue problem in the two analyses are solved using the boundary value problem solver bvp4c routine in MATLAB. Comparisons between linear and nonlinear analyses are presented, supported by graphical representations of stability boundaries. The results reveal that longitudinal rolls are the most unstable modes and that inclination has a stabilizing effect, while the non-Newtonian nature of the Casson fluid tends to reduce the stability threshold. Increasing Gebhart number (stronger viscous dissipation) promotes instability, and along-slope buoyancy induced throughflow directionally shifts neutral curves-either amplifying or offsetting dissipation-induced destabilization depending on its direction. These findings provide insights into the complex interplay between fluid rheology, thermal dissipation, and system geometry, contributing to the understanding of thermal convection in porous media filled with non-Newtonian fluids.

本文研究了卡森流体饱和的倾斜多孔层内热对流的开始，并考虑了粘性耗散和沿坡浮力诱导的通流的影响。该系统由两个具有倾角的平行板组成，其中φ来自水平，并使用线性和非线性稳定性特性进行分析。达西定律用于描述流动。首先对控制方程（包括连续性、动量和能量平衡）进行无量纲化，以引入关键参数，如Darcy-Rayleigh数、Gebhart数、倾角和Casson流体指数。采用正态模态技术对扰动进行线性稳定性分析。为了补充线性分析，使用能量方法检查非线性稳定性，其中构造能量泛函以确定全局非线性稳定性的阈值。利用MATLAB中的边值问题求解器bvp4c例程对两种分析中的边值问题进行求解。给出了线性分析和非线性分析的比较，并用稳定性边界的图形表示加以支持。结果表明，纵向滚动是最不稳定的模式，而倾角具有稳定作用，而卡森流体的非牛顿性质倾向于降低稳定阈值。增加格哈特数（更强的粘性耗散）促进了不稳定性，沿坡浮力诱导的通流定向移动中性曲线——根据其方向放大或抵消耗散诱导的不稳定性。这些发现为流体流变学、热耗散和系统几何之间复杂的相互作用提供了见解，有助于理解充满非牛顿流体的多孔介质中的热对流。

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引用次数: 0

First-principles study of the electronic and gas adsorption properties of one dimensional single-chain GaXY (X = S, Se; Y = F, Cl, Br, I) 一维单链GaXY （X = S, Se; Y = F, Cl, Br， I）的电子和气体吸附性质第一性原理研究

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

Chinese Journal of Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.cjph.2025.11.015

Lanyin Liu , Xinghong Cai , Ziyi Ran , Qun Hui , Min Wang

The successful reported synthesis of one-dimensional (1D) helical single-chain Gallium Sulfur Iodine (GaSI) has sparked our interest in this novel material. Using first-principles calculations, we theoretically investigated the structural and electronic properties of GaSI and explored the adsorption of various gases on its surface. 1D GaSI is predicted to be stable at temperatures up to 500 K. The material, GaSI, is characterized by a wide bandgap of 2.05 eV, making it of interest for optoelectronic devices. Computational analysis of the adsorption energies and electronic changes upon gas adsorption on GaSI indicates that GaSI is a promising sensor for detection of Nitrogen Monoxide (NO). After elemental substitution, we also studied other gallium sulfur halides. A related compound Gallium Sulfur Fluoride (GaSF), which is formed after elemental substitution (replacing Iodide with Fluorine) demonstrates enhanced detection properties for NO, highlighting the tunability of this material class. The research concludes that these 1D Gallium Sulfur Halides (like GaSI and GaSF) are viable low-dimensional materials for next-generation technology in several fields like nanoelectronics, optoelectronics, photovoltaics, and sensing applications.

一维（1D）螺旋单链镓硫碘（GaSI）的成功合成引起了我们对这种新材料的兴趣。利用第一性原理计算，从理论上研究了GaSI的结构和电子性质，并探索了各种气体在其表面的吸附。预计1D GaSI在高达500k的温度下是稳定的。该材料，GaSI，具有2.05 eV的宽带隙，使其成为光电器件的兴趣。气体在GaSI上的吸附能和电子变化的计算分析表明，GaSI是一种很有前途的检测一氧化氮（NO）的传感器。元素置换后，我们还研究了其他的硫卤化镓。元素取代（用氟取代碘化物）后形成的相关化合物氟化镓硫（GaSF）对NO的检测性能增强，突出了这类材料的可调性。该研究得出结论，这些一维镓硫卤化物（如GaSI和GaSF）在纳米电子学、光电子学、光伏和传感应用等多个领域是下一代技术的可行低维材料。

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引用次数: 0

Structural, electronic, magnetic, half-metallic, and thermoelectric properties of a novel rare rarth-based quaternary Heusler compounds 一种新型稀有稀土基季系Heusler化合物的结构、电子、磁性、半金属和热电性质

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

Chinese Journal of Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.cjph.2025.11.008

Saadi Berri , Ayache Mebarek Azzem , Djamel Maouche , Çağatay Yamçıçıer

First-principles calculations were performed to investigate the structural, electronic, half-metallic and thermoelectric properties of 27 specific rare-earth-based quaternary Heusler compounds, selected from a palette of R (Pr, Nd, Gd, Tb, La), X (Co, Fe, Ru), Y (Mn, V, Cr), and Z (Al, Ga, In) elements. We have opted for a Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method based on the Density Functional Theory (DFT) as implemented in Wien2k for our calculations. For the comprehensive analysis, PBE-GGA, and TB-mBJ functionals were used. The ground state parameters of RE-EQHs were determined, including the lattice parameter, total energy bulk modulus, and its derivative. The electronic structure of the RE-EQHs under consideration indicates that they are half-metallic ferromagnetic alloys. The total spin magnetic moments for all the half-metals satisfy the Slater-Pauling 18 electron-rule, confirming the existence of the half-metallic gap. The Seebeck coefficient, power factor, and semiclassical Boltzmann theory figure of merit are calculated using Boltztrap code to study these materials' thermoelectric properties. The compounds exhibit exceptionally high Seebeck coefficients (with values up to ≈ 1000 μV/K) and promising thermoelectric figures of merit that approach the ideal benchmark of 1.0 at 900K, positioning them as strong candidates for high-temperature thermoelectric applications.

从R (Pr, Nd, Gd, Tb, La), X (Co, Fe, Ru), Y （Mn， V, Cr）和Z （Al, Ga, In）元素中选择27种特定的稀土基季系Heusler化合物进行第一性原理计算，研究其结构、电子、半金属和热电性质。我们选择了基于密度泛函理论（DFT）的全势线性化增广平面波（FP-LAPW）方法进行计算，该方法在Wien2k中实现。综合分析采用PBE-GGA和TB-mBJ函数。确定了RE-EQHs的基态参数，包括晶格参数、总能量体积模量及其导数。所研究的RE-EQHs的电子结构表明它们是半金属铁磁合金。所有半金属的总自旋磁矩满足Slater-Pauling 18电子规则，证实了半金属间隙的存在。利用玻尔兹阱程序计算了塞贝克系数、功率因数和半经典玻尔兹曼理论优值，研究了这些材料的热电性能。这些化合物具有非常高的塞贝克系数（高达≈1000 μV/K）和有希望的热电值，在900K时接近1.0的理想基准，使它们成为高温热电应用的有力候选者。

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引用次数: 0

Activation cross sections of alpha-particle-induced reactions on niobium-93 up to 50 MeV 在50 MeV以下的铌-93上α粒子诱导反应的激活截面

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

Chinese Journal of Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.cjph.2025.11.038

He Huang , Masayuki Aikawa , Shuichiro Ebata , Kenta Sugihara , Zolbadral Tsoodol , Naoyuki Ukon , Hiromitsu Haba , Sándor Takács , Ferenc Ditrói , Zoltán Szűcs , Tamás Tornyi

Technetium radioisotopes have garnered interest in medical applications. In this study, niobium-93 foils were irradiated with a 50-MeV alpha-particle beam to determine the production cross sections of technetium radioisotopes including ^{96g,95m,95g,94g,93m,93g}Tc, along with ^93mMo, ^{95m,95g,92m,91m,90}Nb, ^89gZr and ^88,87gY. The stacked-foil activation technique and gamma-ray spectrometry were adopted for this experiment. The results were compared with the theoretical values of TALYS based TENDL-2023 library, and the previously published experimental data. Physical thick target yields (TTY) were deduced based on the measured cross sections.

锝放射性同位素在医学上的应用引起了人们的兴趣。本研究采用50 mev α粒子束辐照铌-93箔，测定了96g、95m、95g、94g、93m、93gTc以及93mMo、95m、95g、92m、91m、90Nb、89gZr和88、87gY等锝放射性同位素的生成截面。本实验采用叠箔活化技术和伽马射线能谱法。结果与基于TALYS的TENDL-2023文库的理论值和先前发表的实验数据进行了比较。根据实测截面推导了物理厚靶产率（TTY）。

引用次数: 0