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Fractal time numerical modelling of radiative heat and mass transfer in Carreau–Yasuda mixed convective flow carau - yasuda混合对流中辐射传热传质的分形时间数值模拟

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-12-20 DOI: 10.1016/j.physo.2025.100359

Muhammad Shoaib Arif , Yasir Nawaz , Kamaleldin Abodayeh

This paper demonstrates a computational process in simulating the unsteady radiative mixed convective flow of a Carreau-Yasuda nanofluid by a porous material, when subjected to a magnetic field. Fractal time derivatives are used to model an approach that captures the memory-dependent behaviour of complex transport phenomena. A novel three-stage explicit time integration scheme is developed, delivering third-order temporal accuracy tailored to fractal-time partial differential equations. For spatial discretization, a compact sixth-order scheme is used to improve numerical precision in the interior domain. The proposed framework incorporates thermal and solutal buoyancy effects, nonlinear rheology, Brownian motion, thermophoresis, and contributions from a heat source. It also accounts for the influence of oscillatory boundary conditions and Darcy-Forchheimer drag within porous structures. Rigorous stability and convergence analyses confirm the robustness of the scheme. Quantitative comparisons reveal that at a time step of

Δ t = \frac{0.1}{2250}

, the proposed scheme achieves an

L_{2}

error of

6.72 \times 10^{- 5}

and consumes approximately 97.62 s, while the second-order scheme reaches an error of

1.06 \times 10^{- 4}

with a runtime of 173.82 s under the same compact discretization, highlighting both its efficiency and stability. Numerical experiments demonstrate that the method outperforms existing first- and second-order schemes in both accuracy and computational efficiency. Furthermore, a velocity reduction of over

30 %

observed when increasing the power-law index from 0.6 to 1.2, highlighting enhanced shear-thinning behaviour. The proposed methodology not only ensures numerical stability under fine discretization but also demonstrates robustness in capturing complex flow behaviour in porous, radiatively influenced environments. This fractal-based computational framework offers a valuable tool for simulating non-Newtonian nanofluid systems in emerging thermal technologies. Fractal time derivatives effectively capture memory-dependent, scale-invariant transport phenomena, offering computational advantages and localised accuracy over traditional fractional operators.

本文给出了用多孔材料模拟carau - yasuda纳米流体在磁场作用下的非定常辐射混合对流的计算过程。分形时间导数用于模拟捕获复杂传输现象的记忆依赖行为的方法。开发了一种新的三阶段显式时间积分方案，提供适合分形时间偏微分方程的三阶时间精度。在空间离散化方面，采用紧凑的六阶格式提高了内域的数值精度。提出的框架包括热和溶质浮力效应、非线性流变、布朗运动、热泳动和热源的贡献。它还解释了多孔结构内振荡边界条件和达西-福希海默阻力的影响。严格的稳定性和收敛性分析证实了该方案的鲁棒性。定量比较表明，在时间步长Δt=0.12250时，该方案的L2误差为6.72×10−5，运行时间约为97.62 s，而在同样紧凑的离散化下，二阶方案的L2误差为1.06×10−4，运行时间为173.82 s，突出了其效率和稳定性。数值实验表明，该方法在精度和计算效率上都优于现有的一阶和二阶格式。此外，当幂律指数从0.6增加到1.2时，观察到速度降低超过30%，突出了增强的剪切变薄行为。所提出的方法不仅保证了精细离散下的数值稳定性，而且在捕获多孔、辐射影响环境中的复杂流动行为方面表现出鲁棒性。这种基于分形的计算框架为新兴热技术中模拟非牛顿纳米流体系统提供了一个有价值的工具。分形时间导数有效地捕获了依赖于内存的、尺度不变的传输现象，与传统的分数运算符相比，具有计算优势和局部精度。

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引用次数: 0

Activity concentration levels of natural radionuclides in soils of Anambra State, South-east Nigeria 尼日利亚东南部阿南布拉州土壤中天然放射性核素的活动浓度水平

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-12-19 DOI: 10.1016/j.physo.2025.100361

Charles C. Ajaero , Christian N. Madu , Chukwuebuka C. Okafor , Valentine E. Nnadi , Festus A. Otunomo

Much focus has not been paid to mapping of radionuclides in sedimentary formation in Nigeria. Thus, the relevance of this study which measured (mapped) the activity levels of radionuclides in the soils of Anambra State, Nigeria. Anambra State underlain by a younger sedimentary formation was chosen, as radionuclides levels in soils of older, consolidated sedimentary rocks and Basement complex rocks in Nigeria have been studied. The study measured radionuclides in soils of a predominantly sedimentary geologic formations much under-studied in Nigeria, and assessed how seasonal changes influences natural radionuclides levels in soil. The study was conducted for the dry and wet seasons of 2022. The study area, Anambra, was stratified into two geological formations, and twenty sampling points used. The major study objective is to determine the activity level of the radionuclides (U-238, Th-232, K-40, Ra-226) in the soil and; determine whether there is variation between the seasons (dry and wet). Our results show that there were variations in the levels of radionuclides (U-238, Th-232, K-40, Ra-226) between the dry and wet seasons based on the geologic formation. The levels of the radionuclides are generally higher in dry season than the wet season (U-238, Th-232, K-40, Ra-226). This was attributed to lack of moisture, which dampens gamma radiation. The study also showed that the levels of U-238 and Th-232 were significantly higher than their respective UNSCEAR (2000) population weighted averages in Ayamelum (Imo Shale), while they were significantly lower in the other locations- Orumba North (Imo Shale), Anambra East and Aguata (Nanka Shale). The levels of Ra-226 levels were significantly higher than UNSCEAR (2000) population weighted averages in all the locations. However, the levels of K-40 in all the locations were significantly lower than the population weighted averages. The study results also showed that statistically, the levels of U-238, Th-232 and Ra-226 in the soils varied between the two seasons (wet and dry). However, there was no statistically significant difference in the level of K-40 between the two seasons. The result finding therefore implies that season influences the levels of U-238, Th-232 and Ra-226 in the soils. Environmental factors may also be influencing the significant variations in radionuclides levels (U-238 and Th-232) in soils at different locations of the study area underlain by the same geologic formation.

对尼日利亚沉积地层中的放射性核素作图没有给予太多的关注。因此，这项研究测量（绘制）了尼日利亚阿南布拉州土壤中放射性核素的活动水平。之所以选择位于较年轻沉积地层之下的阿南布拉州，是因为研究了尼日利亚较老的固结沉积岩和基底复杂岩石土壤中的放射性核素水平。该研究测量了尼日利亚主要沉积地质构造土壤中的放射性核素，并评估了季节变化如何影响土壤中的天然放射性核素水平。这项研究是在2022年旱季和雨季进行的。研究区阿南布拉（Anambra）被划分为两个地质构造，使用了20个采样点。主要的研究目标是确定土壤中放射性核素（U-238、Th-232、K-40、Ra-226）的活动水平；确定季节（干季和湿季）之间是否有变化。结果表明，根据地质构造，旱季和雨季放射性核素（U-238、Th-232、K-40、Ra-226）水平存在差异。旱季的放射性核素含量通常高于雨季（U-238、Th-232、K-40、Ra-226）。这是由于缺乏水分，而水分会抑制伽马射线。该研究还表明，在Ayamelum （Imo页岩），U-238和Th-232的水平明显高于各自的UNSCEAR（2000）人口加权平均值，而在其他地点- Orumba North （Imo页岩），Anambra East和Aguata （Nanka页岩），U-238和Th-232的水平明显较低。所有地点的Ra-226水平明显高于联合国科委会（2000年）人口加权平均水平。但各地点的K-40水平均显著低于种群加权平均值。研究结果还表明，在统计上，土壤中U-238、Th-232和Ra-226的含量在两个季节（湿季和旱季）之间存在差异。但两季间K-40含量差异无统计学意义。结果表明，季节影响土壤中U-238、Th-232和Ra-226的含量。环境因素也可能影响同一地质构造下研究区不同地点土壤中放射性核素（U-238和Th-232）水平的显著差异。

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引用次数: 0

Machine learning Calabi–Yau three-folds, four-folds, and five-folds 机器学习Calabi-Yau三倍，四倍，五倍

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-12-18 DOI: 10.1016/j.physo.2025.100360

Kaniba Mady Keita , Younouss Hamèye Dicko

In this manuscript, we demonstrate, using several regression techniques, that the remaining independent Hodge numbers of complete intersection Calabi–Yau four-folds and five-folds can be machine learned from

h^{1, 1}

and

h^{2, 1}

. Consequently, we combine the Hodge numbers

h^{1, 1}

and

h^{2, 1}

from the complete intersection Calabi-Yau three-folds, four-folds, and five-folds into a single dataset. We then implement various classification algorithms on this dataset. For example, Gaussian process and naive Bayes classifiers both achieve 100% accuracy in binary classification between three-folds and four-folds. Using the Support Vector Machine (SVM) algorithm, a special corner is identified in the Calabi–Yau four-fold landscape (characterized by

15 \leq h^{1, 1} \leq 30

and

95 \leq h^{2, 1} \leq 100

) during multiclass classification. Furthermore, the highest accuracy 1.00000, in classifying Calabi–Yau three-folds, four-folds, and five-folds is obtained using the naive Bayes classifier.

在本文中，我们使用几种回归技术证明，完全相交Calabi-Yau四倍和五倍的剩余独立Hodge数可以从h1,1和h2,1机器学习。因此，我们将来自Calabi-Yau的完整交集的三倍、四倍和五倍的Hodge数h1,1和h2,1合并为一个单一的数据集。然后我们在这个数据集上实现各种分类算法。例如，高斯过程和朴素贝叶斯分类器在三倍和四倍之间的二元分类中都达到了100%的准确率。利用支持向量机（SVM）算法，在Calabi-Yau四重景观（特征为15≤h1,1≤30和95≤h2,1≤100）进行多类分类时，识别出一个特殊的角点。此外，使用朴素贝叶斯分类器对Calabi-Yau进行三倍、四倍和五倍分类的准确率最高，达到100万。

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引用次数: 0

Numerical treatment of Benjamin–Bona–Mahony–Burgers equation via integration of compact finite difference method with SSP-RK 利用紧致有限差分法与SSP-RK的积分对Benjamin-Bona-Mahony-Burgers方程进行数值处理

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-12-16 DOI: 10.1016/j.physo.2025.100355

Ravneet Kaur , Geeta Arora , Homan Emadifar

In this work, a sixth-order compact finite difference method (CFDM6) is investigated to obtain the numerical solution of Benjamin–Bona–Mahony–Burgers equation (BBMBE). The compact finite-difference technique is used to approximate spatial derivatives at internal points and at the additional nodes. The time derivative is analyzed by a strong stability-preserving Runge–Kutta method of four stages and third order. The stability analysis of the proposed method is conducted to validate its stability. To validate the effectiveness and precision of the proposed method, the error norms

L_{2}

and

L_{\infty}

are calculated for different illustrations. The analytical and numerical solutions from the literature are compared and presented in tables and graphs. The comparison shows that the computed values, are in good agreement, with the exact solution. This justifies the proficiency, precision, and computational implementation of the proposed method.

本文研究了一种六阶紧致有限差分法（CFDM6）来获得Benjamin-Bona-Mahony-Burgers方程（BBMBE）的数值解。利用紧致有限差分技术逼近内部点和附加节点的空间导数。采用四阶三阶强保稳龙格-库塔方法对时间导数进行了分析。对该方法进行了稳定性分析，验证了其稳定性。为了验证所提方法的有效性和精度，计算了不同实例的误差范数L2和L∞。对文献中的解析解和数值解进行了比较，并以表格和图表的形式呈现出来。结果表明，计算值与精确解吻合较好。这证明了所提出方法的熟练度、精度和计算实现。

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引用次数: 0

Structural, morphological, thermodynamic, and magnetic properties of Sm2Ni2O5: influence of co-precipitation vs sol-gel synthesis Sm2Ni2O5的结构、形态、热力学和磁性能：共沉淀法对溶胶-凝胶合成的影响

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-12-13 DOI: 10.1016/j.physo.2025.100358

Khethiwe Cele , Sibusiso Nqayi , Reddy Leelakrishna , Buyisiwe Sondezi

Crystalline Sm₂Ni₂O₅ nanoparticles (SNONPs) were synthesized via Co-precipitation and Sol-gel methods to examine how synthesis influences structural, morphological, thermodynamic, and magnetic properties. XRD confirmed both samples crystallized into an orthorhombic Ima2 structure after annealing at 800 °C for 6 h. SEM showed compact, smooth particles for Co-precipitated samples and brittle, fragmented ones for Sol-gel samples. EDS verified all expected elements with slight oxygen variation. Specific heat (0–300 K, 0.5 T) revealed distinct phase transitions: a 6 K anomaly indicating spin freezing in the Sm³⁺–O–Sm³⁺ framework; antiferromagnetic (AFM) ordering at T_N = 9 K from Ni²⁺–O–Ni²⁺ interactions; and a ferromagnetic (FM) transition at T_C = 43.6 K associated with Ni²⁺–O–Ni³⁺ sublattices. Above T_C, a paramagnetic (PM) phase emerged. The synthesis methods significantly affect crystallinity, governing magnetic and thermodynamic activities emphasizing SNONPs promise for spintronic and low-temperature magnetic applications.

采用共沉淀法和溶胶-凝胶法合成了结晶Sm2Ni2O5纳米粒子（SNONPs），研究了合成对Sm2Ni2O5结构、形态、热力学和磁性能的影响。XRD证实，在800℃下退火6 h后，两种样品均结晶成正交Ima2结构。SEM显示，co -析出样品的颗粒致密、光滑，而溶胶-凝胶样品的颗粒脆性、破碎。EDS验证了所有期望元素，氧含量有轻微变化。比热（0-300 K, 0.5 T）显示出明显的相变：6 K异常表明Sm3+ -O-Sm3 +框架中自旋冻结；Ni2+ -O-Ni2 +相互作用在TN = 9 K下的反铁磁（AFM）排序；以及在TC = 43.6 K下与Ni2+ -O-Ni3 +亚晶格相关的铁磁（FM）跃迁。在TC上方，出现顺磁（PM）相。合成方法显著影响SNONPs的结晶度、控制磁性和热力学活动，强调SNONPs在自旋电子和低温磁性应用方面的前景。

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引用次数: 0

Different phase matching schemes of terahertz wave generation using periodic poled lithium niobate for real-world applications 利用周期性极化铌酸锂产生太赫兹波的不同相位匹配方案在现实世界中的应用

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-12-11 DOI: 10.1016/j.physo.2025.100357

Ugrasen Singh , Abhinav Kumar , Prashant Povel Dwivedi , Ajay Mishra , Nimish Dixit

Terahertz (THz) wave generation through periodic poled lithium niobate (PPLN) has gained significant attention due to its potential applications in spectroscopy, imaging, communication, and security screening. Among various nonlinear optical materials, lithium niobate (LiNbO₃) has emerged as a promising medium for efficient THz generation due to strong nonlinear optical properties and wide transparency range. However, achieving efficient energy conversion requires effective phase matching to overcome phase velocity mismatch between the pump and the generated THz waves. Several phase-matching schemes have been explored to optimize THz generation. This review comprehensively discusses these schemes, analyzing their theoretical principles, experimental implementations, and practical applications. A comparative analyze is also provided to highlight the advantages and limitations of each approach. The presented literature aims to guide researchers in selecting appropriate phase-matching configurations for THz generation.

通过周期性极化铌酸锂（PPLN）产生太赫兹（THz）波，由于其在光谱、成像、通信和安全筛查方面的潜在应用而受到了极大的关注。在各种非线性光学材料中，铌酸锂（LiNbO3）由于其较强的非线性光学性质和较宽的透明度范围而成为一种有前途的高效太赫兹产生介质。然而，实现高效的能量转换需要有效的相位匹配来克服泵浦与产生的太赫兹波之间的相速度不匹配。研究了几种相位匹配方案来优化太赫兹的产生。本文全面讨论了这些方案，分析了它们的理论原理、实验实现和实际应用。还提供了比较分析，以突出每种方法的优点和局限性。本文旨在指导研究人员为太赫兹产生选择合适的相位匹配配置。

引用次数: 0

Chemical shifts in the Kα1,2 and Kβ1,3 X-ray emission spectra for halogen compounds of elements with atomic numbers ranging from 22 to 29 were measured using a wavelength-dispersive X-ray fluorescence spectrometer 用波长色散x射线荧光光谱仪测量了原子序数为22 ~ 29的元素的卤素化合物的k α1,2和k β1,3的x射线发射光谱的化学位移

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-12-11 DOI: 10.1016/j.physo.2025.100316

E. Boydaş

This study aimed to investigate the chemical shifts and full widths at half maximum (FWHM) of the Kα_1,2 and Kβ₁,₃ X-ray emission lines in selected halogen compounds of elements with atomic numbers ranging from 22 to 29. A Wavelength-Dispersive X-ray Fluorescence (WDXRF) spectrometer was employed for this analysis. The FWHM differences (ΔFWHM) of these emission lines were calculated by using the corresponding metallic element as a reference. The data revealed a clear pattern, showing larger chemical shifts for fluorine-containing compounds compared to chlorine-containing ones. In addition, the Kβ_1,3 lines generally show larger chemical shifts and wider full widths at half maximum (FWHM) compared to the Kα lines. The chemical shift also tends to increase as the number of coordinating ligand atoms rises.

本研究旨在研究选定的原子序数为22 ~ 29的元素的卤化物中k α1,2和k β1,3 x射线发射谱线的化学位移和半峰全宽度。采用波长色散x射线荧光（WDXRF）光谱仪进行分析。以相应的金属元素为参考，计算了这些发射线的FWHM差（ΔFWHM）。数据显示出一种清晰的模式，即含氟化合物的化学变化比含氯化合物大。此外，与Kα谱线相比，k β1,3谱线普遍表现出更大的化学位移和更宽的半峰全宽。随着配位体原子数量的增加，化学位移也趋于增加。

引用次数: 0

A physics-informed neural network framework for modeling rogue and breather solutions in conformable fractional nonlinear wave systems 符合分数阶非线性波动系统中流氓解和呼吸解建模的物理信息神经网络框架

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-12-09 DOI: 10.1016/j.physo.2025.100356

Md. Towhiduzzaman , Md. Abdul Al Mohit , A.Z.M. Asaduzzaman

This study presents a robust and generalized Physics-Informed Neural Network (PINN) framework for solving a class of conformable fractional nonlinear wave equations (CFNWEs). These equations are widely used in modeling complex wave dynamics in physical systems exhibiting memory and hereditary effects. By embedding the conformable fractional operator directly into the neural network architecture, the proposed model accurately captures localized nonlinear structures, including rogue waves and breather-type solutions. The framework employs a composite loss function integrating initial, boundary, and PDE residual constraints, optimized through a hybrid training strategy combining Adam and L-BFGS optimizers. Extensive numerical experiments validate the accuracy, physical consistency, and reproducibility of the proposed approach, demonstrating close agreement with analytical solutions. Moreover, the model exhibits robust performance under sparse and noisy data conditions, highlighting its potential for broad applications in wave dynamics, viscoelastic media, and nonlinear signal forecasting.

本文提出了一个鲁棒的广义物理信息神经网络（PINN）框架，用于求解一类可调分数阶非线性波动方程（CFNWEs）。这些方程被广泛用于模拟具有记忆和遗传效应的物理系统中的复杂波动动力学。通过将符合分数算子直接嵌入到神经网络结构中，该模型可以准确捕获局部非线性结构，包括异常波和呼吸型解。该框架采用了一个综合了初始、边界和PDE残差约束的复合损失函数，并通过结合Adam和L-BFGS优化器的混合训练策略进行了优化。大量的数值实验验证了所提出方法的准确性、物理一致性和可重复性，证明了与解析解的密切一致。此外，该模型在稀疏和噪声数据条件下表现出鲁棒性，突出了其在波动动力学、粘弹性介质和非线性信号预测方面的广泛应用潜力。

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引用次数: 0

Computational analysis of Hall current, radiation absorption and diffusion thermo effects on unsteady MHD rotating flow of Casson fluid through porous media with chemical reaction 霍尔电流、辐射吸收和扩散热效应对卡森流体非定常MHD旋转多孔介质化学反应的计算分析

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-12-01 DOI: 10.1016/j.physo.2025.100351

G. Siddesh Babu , R. Bhuvana Vijaya

This study investigates the unsteady free-convective flow of an electrically conducting Casson fluid through a porous medium under the combined influences of Hall current, radiation absorption, Dufour effect, thermal radiation, Joule heating, viscous dissipation, and a homogeneous chemical reaction. The fluid motion is subjected to a uniform transverse magnetic field with variable permeability and oscillatory suction. The governing nonlinear partial differential equations for momentum, energy, and concentration are formulated and transformed into dimensionless form using appropriate similarity transformations. Closed-form analytical solutions are obtained through a perturbation method applied for small fluctuations in permeability. The analysis highlights the roles of key parameters—including the Hall parameter (m), magnetic parameter (M), Dufour number (Du), Prandtl number (Pr), Schmidt number (Sc), thermal and solutal Grashof numbers (Gr, Gm), chemical reaction rate (Kc), radiation parameter (Q₁), Joule heating parameter, viscous dissipation parameter, and rotation parameter (R)—on velocity, temperature, and concentration distributions. Engineering quantities such as skin friction, Nusselt number, and Sherwood number are also evaluated. The results show that Hall current enhances secondary flow but increases skin friction, while Dufour effect, radiation absorption, Joule heating, and viscous dissipation significantly elevate fluid temperature. Chemical reaction accelerates mass transfer, and rotation reduces magnetic damping, lowering frictional resistance. These findings provide valuable insights for optimizing heat and mass transfer in MHD energy systems, thermal processing operations, and chemically reactive porous-media environments.

本文研究了导电卡森流体在霍尔电流、辐射吸收、杜福效应、热辐射、焦耳加热、粘滞耗散和均相化学反应共同作用下在多孔介质中的非定常自由对流流动。流体运动受到具有可变磁导率和振荡吸力的均匀横向磁场的影响。控制非线性偏微分方程的动量，能量，和浓度是制定和转换成无因次形式使用适当的相似变换。采用微扰法对渗透率的小波动进行了分析，得到了闭式解析解。分析强调了关键参数——包括霍尔参数(m)、磁性参数(m)、杜弗数（Du）、普朗特数（Pr）、施密特数（Sc）、热和溶质Grashof数（Gr, Gm）、化学反应速率（Kc）、辐射参数（Q1）、焦耳加热参数、粘性耗散参数和旋转参数(R)——对速度、温度和浓度分布的作用。工程数量，如皮肤摩擦，努塞尔数和舍伍德数也进行了评估。结果表明，霍尔电流增强了二次流，但增加了表面摩擦，而杜福效应、辐射吸收、焦耳加热和粘性耗散显著提高了流体温度。化学反应加速传质，旋转减少磁阻尼，降低摩擦阻力。这些发现为优化MHD能源系统的传热传质、热加工操作和化学反应性多孔介质环境提供了有价值的见解。

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引用次数: 0

Design of conformal dual stop band frequency selective surface for microwave applications 微波共形双阻带频率选择表面的设计

IF 1.4 Q2 Physics and Astronomy

Physics Open

Pub Date : 2025-11-26 DOI: 10.1016/j.physo.2025.100352

Naveena Meka, Krishnan Shambavi

A Conformal single layer ultra-thin dual band stop and bandpass Frequency Selective Surface (FSS) for microwave applications is proposed and experimentally evaluated in this letter. The proposed FSS uniquely combines dual passband functionality allowing the lower and upper WLAN spectra—with dual stopband performance that delivers wideband, wide-angle, and polarization-independent shielding for TE and TM polarizations. The proposed FSS consists of two Concentric Square Rings (CCSR) and two Convoluted Square Rings (CVSR) on a Rogers 3010 substrate of relative permittivity 10.2 and thickness 0.25 mm. The dimension of the unit cell is 0.1123λo × 0.1123λo, λo is the lowest resonant frequency. Planar and conformal FSS structures were systematically analyzed, fabricated, and characterized in an anechoic chamber to evaluate their passband performance and shielding effectiveness. The proposed FSS exhibits dual wide stopband characteristics ranging from 1.05 to 1.75 GHz, 3.4–4.6 GHz with shield effectiveness of 51 dB and 45 dB at 1.4 GHz, 4.06 GHz respectively. It also exhibits dual pass band response from 2.2 to 2.5 GHz and 5.4–5.9 GHz within band with insertion loss of 0.8 dB and 0.5 dB respectively. It also exhibits outstanding angular and polarization stability up to 80°. The close correlation between simulated and measured transmission responses validates the design's effectiveness in shielding the L band and 5G NR spectrum while maintaining high transmission in the lower and upper WLAN frequency bands.

本文提出了一种用于微波应用的共形单层超薄双带阻带通频率选择表面（FSS），并进行了实验评估。所提出的FSS独特地结合了双通带功能，允许较低和较高的WLAN频谱，并具有双阻带性能，可为TE和TM极化提供宽带，广角和偏振无关的屏蔽。该FSS由两个同心方环（CCSR）和两个卷积方环（CVSR）组成，位于相对介电常数为10.2、厚度为0.25 mm的Rogers 3010衬底上。单元胞的尺寸为0.123 λo × 0.1123λo， λo为最低谐振频率。在消声室中对平面和共形FSS结构进行了系统的分析、制作和表征，以评估其通带性能和屏蔽效果。该FSS具有1.05 ~ 1.75 GHz、3.4 ~ 4.6 GHz的双宽阻带特性，在1.4 GHz、4.06 GHz频段屏蔽效率分别为51 dB和45 dB。在2.2 ~ 2.5 GHz和5.4 ~ 5.9 GHz频段内具有双通带响应，插入损耗分别为0.8 dB和0.5 dB。它还具有出色的角度和偏振稳定性高达80°。模拟和测量的传输响应之间的密切相关性验证了该设计在屏蔽L频段和5G NR频谱同时保持WLAN上下频段高传输的有效性。

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引用次数: 0