Journal of Quantitative Spectroscopy & Radiative Transfer最新文献_第4页

Adaptive angular resolution for time-dependent radiative transfer simulations based on local radiation field anisotropy 基于局地辐射场各向异性的时变辐射传输模拟自适应角分辨率

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.jqsrt.2026.109820

Makito Abe , Hidenobu Yajima , Masayuki Umemura , Yoko Hoshi

Developing a fast and accurate radiative transfer calculation method is vital in modeling light propagation in biological tissues. We present a novel acceleration scheme for three-dimensional time-dependent radiative transfer simulation. In biological tissues, required angular resolutions for anisotropic radiation fields sensitively depend on spatial positions. Our new scheme changes the angular resolutions with the positions automatically based on local anisotropies of the radiation fields using the spherical Haar wavelet basis function. We apply the new code to simulations of light propagation in a box of polyurethane phantom mimicking biological tissue. We show that the new scheme achieves the acceleration of a factor of

\sim 8

at most and

\sim 3

on average compared to a simulation with the constant angular resolution while its accuracy keeps the same level. We find that the acceleration becomes more noticeable if low-angular resolution areas spread with time according as the diffuse radiation dominates. As the result of the fewer required angular bins, we find that the new code has the potential to reduce the memory use to

\sim 20 %

at the maximum. Thus, our new scheme also has the advantage from the viewpoint of computational resources. We note that our new scheme is applicable not only to steady-state media but also to scenarios where the physical state of matter changes dynamically. Our new scheme will be a powerful tool to perform radiative transfer simulations of more than a thousand models which must be important in developing machine learning models.

建立一种快速准确的辐射传递计算方法对模拟光在生物组织中的传播具有重要意义。提出了一种新的三维时变辐射传输模拟加速方案。在生物组织中，各向异性辐射场所需的角分辨率敏感地依赖于空间位置。该方案基于辐射场的局部各向异性，利用球面Haar小波基函数自动改变角分辨率随位置的变化。我们将新代码应用于模拟生物组织的聚氨酯幻影盒中的光传播模拟。我们表明，与具有恒定角度分辨率的模拟相比，新方案最多实现了~ 8倍的加速度，平均实现了~ 3倍的加速度，而其精度保持在相同的水平。我们发现，如果低角分辨率区域随着时间的推移而扩散，则加速度变得更加明显，因为漫射辐射占主导地位。由于所需的角度箱较少，我们发现新代码有可能将内存使用最多减少到20%。因此，从计算资源的角度来看，我们的新方案也具有优势。我们注意到，我们的新方案不仅适用于稳态介质，也适用于物质物理状态动态变化的情况。我们的新方案将是一个强大的工具，可以对一千多个模型进行辐射传输模拟，这在开发机器学习模型中非常重要。

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引用次数: 0

Bidirectional reflectance of seawater 海水的双向反射

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.jqsrt.2026.109818

V.V. Marinyuk , M.A. Pavlova , D.B. Rogozkin , S.V. Sheberstov

A method is proposed for calculating the diffuse component of the bidirectional reflectance distribution function (BRDF) of a medium with relatively strong absorption, such as seawater. Our approach is based on the expansion of the reflectance in orders of scattering through large angles (compared to the characteristic single-scattering angle), which leads to the reflectance expansion in inverse powers of the absorption coefficient. Explicit expressions for the first two terms of the expansion are derived. The first term reproduces the well-known result of quasi-single-scattering approximation, and the second one corresponds to the contribution of quasi-double scattering (the small-angle multiple scattering before, between, and after two events of large-angle scattering). To validate our analytical results, we carry out numerical integration of the radiative transfer equation for the Henyey–Greenstein (HG) phase function, as well as for the two-term HG and Morel et al (for Case I water) ones. For optical parameters typical to seawater, our analytical formula is in excellent agreement with the results of numerical radiative transfer calculations over a wide range of illumination/viewing angles. Remarkably, the relative contribution of the quasi-double scattering proves to be rather sensitive to the shape of the phase function in the backward hemisphere.

提出了一种计算吸收较强介质（如海水）双向反射分布函数（BRDF）漫射分量的方法。我们的方法是基于反射率在大角度（与特征的单散射角相比）的散射级数的扩展，这导致反射率以吸收系数的反比幂的方式扩展。导出展开式的前两项的显式表达式。第一项再现了众所周知的准单散射近似结果，第二项对应于准双散射的贡献（两个大角散射事件之前、之间和之后的小角多重散射）。为了验证我们的分析结果，我们对Henyey-Greenstein （HG）相函数以及两项HG和Morel等人（情况1水）的辐射传递方程进行了数值积分。对于典型的海水光学参数，我们的分析公式与大范围照明/视角下的数值辐射传递计算结果非常吻合。值得注意的是，准双散射的相对贡献对后半球相函数的形状非常敏感。

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引用次数: 0

Broadband spectrometry and thermal radiative properties of lunar dust simulants 月球尘埃模拟物的宽带光谱分析和热辐射特性

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.jqsrt.2026.109821

Aravintha Raj Ravichandran, Vanessa Bristow, Joohyun Seo, Richard Z. Zhang

Spectrometry of lunar dust simulants can provide better understanding of the Moon’s surface albedo, thermal radiation to its environment, detection of composition variations, and identifying presence of water. The Moon’s soil or regolith is composed of fine dust particles of mostly silica, alumina, and lime, with variations between lighter Highlands (Artemis) regions and darker Mares (Apollo) valleys. To better understand the variations on optical properties, we perform broadband diffuse and specular spectrometry from visible to far-infrared wavelengths of four Lunar regolith simulants. Dust simulants of coarse and fine blends were imaged in scanning electron microscope to validate the particle size distributions. In the visible to near-IR, fine-particle simulants show fewer differences in solar absorption and albedo, while FTIR measurements show compositional oxide differences. Surface absorptivity can vary between 0.63 at the Highlands and 0.79 in Mares, while Lunar albedo obtained from specular spectrometry relative to a Lambertian white reflecting standard can range between 0.79 and 0.64, respectively. Using diffuse FTIR spectrometry, thermal emissivity relative to room temperature blackbody across all Lunar simulants are around 0.78. Variations in spectral reflectance and emittance are dependent on sample humidity and heat treatments, aggregate packing, and scattering from large particles. This work can improve optical sensing methods, dust processing, and in situ resource manufacturing of Lunar regolith.

月球尘埃模拟物的光谱分析可以更好地了解月球表面的反照率、对其环境的热辐射、检测成分变化以及识别水的存在。月球的土壤或风化层主要由二氧化硅、氧化铝和石灰组成的细粉尘颗粒组成，在较亮的高地（阿尔忒弥斯）地区和较暗的马雷斯（阿波罗）山谷之间存在差异。为了更好地理解光学特性的变化，我们对四种月球风化模拟物进行了从可见光到远红外波段的宽带漫射和镜面光谱分析。用扫描电子显微镜对粗粉和细粉模拟粉尘进行了成像，验证了模拟粉尘的粒径分布。在可见光到近红外波段，细颗粒模拟在太阳吸收和反照率方面的差异较小，而FTIR测量显示成分氧化物的差异。高地的表面吸收率可以在0.63和马鞍山的0.79之间变化，而月球反照率相对于朗伯氏白反射标准，通过镜面光谱法得到的反照率分别在0.79和0.64之间。利用漫射红外光谱法，所有月球模拟物相对于室温黑体的热发射率约为0.78。光谱反射率和发射率的变化取决于样品的湿度和热处理、聚集体的堆积和大颗粒的散射。这项工作可以改进月球风化层的光学传感方法、尘埃处理和原位资源制造。

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引用次数: 0

Relativistic multiconfiguration calculations of energy levels, transition rates and hyperfine constants in neutral indium 中性铟中能级、跃迁速率和超细常数的相对论多组态计算

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.jqsrt.2026.109812

B. Atalay

Energies for states of the

5 s^{2} n p

(n = 5 - 8)

,

5 s^{2} 4 f

odd and the

5 s^{2} n s

(n = 6 - 8)

,

5 s^{2} n d

(n = 5, 6)

, and

5 s 5 p^{2}

even configurations in neutral indium are obtained using the fully relativistic multiconfiguration Dirac–Hartree–Fock (MCDHF) method. Transition probabilities and oscillator strengths among all these states are given. The magnetic dipole and electric quadrupole hyperfine structure constants are evaluated. To ensure robustness and reliability of the results, different computational strategies and correlation models were used. Employing a natural orbital basis improves the accuracy of computed values significantly and gives better agreement with the experimental values.

利用完全相对论多组态dirac - hartee - fock （MCDHF）方法，得到了中性铟中5s2np（n=5−8）、5s24f奇态和5s2ns（n=6−8）、5s2 （n=5,6）和555p2偶态的能量。给出了这些状态之间的跃迁概率和振子强度。计算了磁偶极子和电四极子的超精细结构常数。为了保证结果的鲁棒性和可靠性，采用了不同的计算策略和相关模型。采用自然轨道基大大提高了计算值的精度，与实验值的吻合度更高。

引用次数: 0

From light diffusion to photocatalytic rates: Compact scaling laws for strongly scattering porous slabs 从光扩散到光催化速率：强散射多孔板的紧凑结垢规律

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.jqsrt.2026.109819

Renaud A.L. Vallée, Rénal Backov

Light transport in strongly scattering porous photocatalytic materials governs the spatial distribution of absorbed photons and therefore the generation of charge carriers driving photocatalytic reactions. Yet translating measured optical properties of such media into intrinsic reaction rate constants remains challenging, as it requires simultaneously accounting for multiple scattering, boundary losses, photochemical efficiency, and surface kinetics. Here we develop a compact analytical framework that unifies these processes for nanoparticle-loaded photocatalytic slabs. Using a finite-slab diffusion model with extrapolated boundaries, we derive closed-form expressions for the fluence field and couple them to a photochemical quantum efficiency and first-order surface kinetics. The resulting predictors yield intrinsic volumetric and areal rate constants whose dependence on the transport mean free path, optical thickness, and surface-to-volume ratio emerges transparently.

Validation against Monte-Carlo photon-migration simulations shows that the diffusion approximation reproduces the fluence and generation-rate profiles with a modest multiplicative mismatch, typically within a factor of

\sim

1.20–1.39, depending on the anisotropy and scattering phase function. This level of agreement is consistent with the known limits of the diffusion approximation and is sufficient to enable reliable, design-oriented predictions.

The analytical descriptors introduced here – such as

ℓ^{*}

,

S / V

, and the extrapolation length

z_{b}

– are general, physically interpretable, and directly integrable into data-driven optimisation and geometry-engineered reactor design. The framework thus provides a versatile and physically grounded tool for photocatalytic systems across diverse applications, including VOC photo-degradation, indoor air purification, and solar-fuel production.

强散射多孔光催化材料中的光输运控制着吸收光子的空间分布，从而产生驱动光催化反应的载流子。然而，将测量到的这种介质的光学性质转化为固有的反应速率常数仍然具有挑战性，因为它需要同时考虑多重散射、边界损失、光化学效率和表面动力学。在这里，我们开发了一个紧凑的分析框架，统一了纳米颗粒负载光催化板的这些过程。利用具有外推边界的有限板扩散模型，我们推导出了通量场的封闭表达式，并将其与光化学量子效率和一阶表面动力学耦合。由此产生的预测因子产生固有的体积和面速率常数，其依赖于传输平均自由程，光学厚度和表面体积比透明地显现出来。

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引用次数: 0

Transmittance of Gaussian beam in anisotropic jet engine exhaust turbulence 各向异性喷气发动机排气湍流中高斯光束的透射率

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-08 DOI: 10.1016/j.jqsrt.2026.109816

Yahya Baykal

Transmittance is a metric that provides information on how much of the intensity is transferred to the receiver for a given medium. One of the definitions of transmittance is the ratio of the average received intensity in the presence of turbulence to the received intensity in the absence of turbulence. Under such definition, transmittance is found in an anisotropic jet engine exhaust turbulent environment. For various receiver points, transmittances versus the wireless optical communication (WOC) link and anisotropic jet engine exhaust turbulence parameters are presented. The results are useful for designers of WOC links that are installed in the premises such as the airports that possess jet engine exhaust turbulence.

透光率是一种度量，它提供了给定介质中有多少强度被传递到接收器的信息。透光率的定义之一是存在湍流时的平均接收强度与没有湍流时的接收强度之比。在此定义下，得到了各向异性喷气发动机排气湍流环境下的透光率。对于不同的接收点，给出了无线光通信（WOC）链路的透射率和各向异性喷气发动机排气湍流参数。这些结果对于安装在具有喷气发动机排气湍流的机场等场所的WOC链路的设计者是有用的。

引用次数: 0

Tunable pixelated graphene based thermal infrared emitter array and its electrothermal characterization 基于可调谐像素化石墨烯的热红外发射器阵列及其电热特性

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-08 DOI: 10.1016/j.jqsrt.2026.109817

Yibai Zhong , Xiu Liu , Zexiao Wang , Jingyi Zou , Tianyi Huang , Sen Lin , Xiao Luo , Zhuo Li , Rui Cheng , Xu Zhang , Sheng Shen

In this work, we design and fabricate tunable pixelated infrared emitter arrays based on graphene transistors. We use finite element analysis to simulate a 5-by-3 pixelated emitter array, where localized heating area can be confined within a size of 25 μm and reaches more than 10 K temperature rise within 3 μs. By applying fast sweeping scheme with electrostatic voltage inputs, tunable surface patterns assembling dynamic alphabetical letters of microscale sizes are demonstrated and captured via thermal mapping with its thermal emission variation caused by localized temperature rise. Our results show that thermal emission can be highly localized and reconfigurable both spatially and temporally, which paves the way for developing and boosting the performance of microscale and nanoscale thermally driven devices for communication, characterization, sensing and actuation.

在这项工作中，我们设计和制造了基于石墨烯晶体管的可调谐像素化红外发射器阵列。利用有限元方法模拟了一个5 × 3像素的发射极阵列，该阵列的局部加热区域可以限制在25 μm内，并在3 μs内达到10 K以上的温升。通过采用静电电压输入的快速扫描方案，展示并捕获了由微尺度动态字母组成的可调表面图案，并通过热成像捕获了其局部温升引起的热发射变化。我们的研究结果表明，热发射在空间和时间上都是高度局域化和可重构的，这为开发和提高用于通信、表征、传感和驱动的微尺度和纳米尺度热驱动器件的性能铺平了道路。

引用次数: 0

Determination and uncertainty analysis of three-dimensional temperature distribution of non-uniform flame using multi-spectral light field imaging based on backward Monte Carlo method 基于后向蒙特卡罗法的多光谱光场成像非均匀火焰三维温度分布测定及不确定度分析

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-08 DOI: 10.1016/j.jqsrt.2026.109814

Tianjiao Li , Dong Liu

The precise three-dimensional temperature distribution measurement in large-scale furnaces is crucial for industrial efficiency and safety, yet remains challenging due to the inherent ill-posedness and complex radiative properties of flames. This study presents a multi-spectral light field imaging (MSLFI) model based on the backward Monte Carlo method, enabling simultaneous imaging of both flame and furnace wall in a single snapshot. By integrating simultaneous iterative and algebraic reconstruction techniques, particularly the Simultaneous Algebraic Reconstruction Technique (SART), our method achieves robust temperature distribution reconstruction. A thorough assessment of imaging accuracy and reconstruction uncertainties is performed, considering microlens array configuration, flame voxel resolution, ray density, flame absorption and scattering properties, wall reflection, spatial resolution, and signal-to-noise ratio. Results indicate that flame absorption properties exert the most significant influence on reconstruction fidelity, followed by scattering properties, wall reflection, spatial resolution, and signal-to-noise ratio, while microlens array configuration, flame voxel resolution and ray density have minimal impact on the accuracy of temperature distribution reconstruction. The proposed approach offers a practical, efficient solution for industrial furnace monitoring and advances the state-of-the-art in non-invasive, high-resolution temperature imaging for combustion systems.

在大型炉中精确的三维温度分布测量对工业效率和安全至关重要，但由于火焰固有的病态和复杂的辐射特性，仍然具有挑战性。本文提出了一种基于后向蒙特卡罗方法的多光谱光场成像（MSLFI）模型，可以在一次快照中同时对火焰和炉壁进行成像。该方法通过结合同步迭代和代数重建技术，特别是同步代数重建技术（SART），实现了鲁棒的温度分布重建。考虑到微透镜阵列配置、火焰体素分辨率、射线密度、火焰吸收和散射特性、壁面反射、空间分辨率和信噪比，对成像精度和重建不确定性进行了全面评估。结果表明，火焰吸收特性对重建保真度影响最大，其次是散射特性、壁面反射、空间分辨率和信噪比，而微透镜阵列配置、火焰体素分辨率和射线密度对温度分布重建精度影响最小。所提出的方法为工业炉膛监测提供了一种实用、高效的解决方案，并推动了燃烧系统的非侵入性、高分辨率温度成像技术的发展。

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引用次数: 0

Volumetric optical properties of alumina-carbon soot hybrid medium in high-speed aircraft plumes 高速飞机羽流中铝碳烟灰混合介质的体积光学性质

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-07 DOI: 10.1016/j.jqsrt.2026.109808

JingYing Li, XiaoXiao Song, ShanShan Fan

The spectral radiation characteristics of aircraft exhaust plumes are significantly influenced by the volumetric optical properties of alumina-carbon soot hybrid media. This study develops a dedicated computational algorithm to determine these properties by establishing realistic models for alumina and carbon soot clusters in the plume and derives formulas for calculating the volumetric optical properties per unit volume of the hybrid medium. The characteristics are analyzed in the ultraviolet (280 nm) and infrared (4.3 µm) bands. The results show that: (1) In the ultraviolet band, the extinction process is primarily governed by scattering from alumina particles, with carbon soot particles accounting for over 99% of the absorption. Conversely, in the infrared band, extinction is dominated by absorption from carbon soot particles, while the contribution of alumina particles to extinction is only 2%–4.5%. (2) In the ultraviolet band, the volumetric scattering phase function of the hybrid medium exhibits strong forward scattering, which decreases with increasing carbon soot content. In the infrared band, the scattering phase function becomes relatively flat, demonstrating isotropic scattering characteristics. (3) Regarding polarization properties, the volumetric linear polarization degree in the ultraviolet band is predominantly negative, and the circular polarization displays a distribution from strong right-handed in the forward direction to strong left-handed in the backward direction. In the infrared band, the linear polarization exhibits a strictly even-symmetric positive distribution about 90°, and the circular polarization shows strict central symmetry about 90°. The conclusions of this study provide a theoretical basis for multi-band radiation characteristic modeling and target identification of high-speed aircraft exhaust plumes.

铝碳混合介质的体积光学特性对飞机排气羽流的光谱辐射特性有显著影响。本研究开发了一种专用的计算算法，通过建立羽流中氧化铝和碳烟簇的现实模型来确定这些特性，并推导出计算混合介质单位体积体积光学特性的公式。在紫外（280 nm）和红外（4.3µm）波段分析了其特性。结果表明：(1)在紫外波段，消光过程主要受氧化铝颗粒的散射控制，碳烟颗粒占吸收的99%以上；相反，在红外波段，碳烟灰颗粒的吸收主导了消光，而氧化铝颗粒对消光的贡献仅为2%-4.5%。(2)在紫外波段，混合介质的体积散射相函数表现出强烈的前向散射，随碳烟含量的增加而减小。在红外波段，散射相函数变得相对平坦，表现出各向同性散射特性。(3)在极化特性上，紫外波段的体积线极化度以负极化为主，圆极化呈现由正向强右手向反向强左手的分布。在红外波段，线偏振呈严格均匀对称的约90°正分布，圆偏振呈严格中心对称的约90°正分布。研究结果为高速飞机排气羽流多波段辐射特性建模和目标识别提供了理论依据。

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引用次数: 0

van de Hulst essay: Geometric-phase portrayal of electromagnetic scattering by a three-dimensional object in free space van de Hulst论文：三维物体在自由空间中电磁散射的几何相位描述

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2026-01-07 DOI: 10.1016/j.jqsrt.2026.109809

Akhlesh Lakhtakia

Quantifying the dissimilarity in the locations of two plane waves on the Poincaré sphere by using spinor algebra, the concept of geometric phase was applied to initiate a novel portrayal of electromagnetic scattering by a three-dimensional object in free space. Whereas the incident electromagnetic field is that of an arbitrarily polarized plane wave, the direction-dependent far-zone scattering amplitude was used to define direction-dependent Stokes parameters for the scattered field. Both symmetric and asymmetric Poincaré spinors were formulated to characterize the polarization states of incident plane wave and the far-zone scattering amplitude, and two different geometric phases were defined therefrom. Density plots of both geometric phases were calculated for six different homogeneous isotropic spheres with different linear constitutive properties and boundary conditions: dielectric–magnetic spheres (non-dissipative and dissipative), impedance spheres, perfect electrically conducting spheres, charged dielectric–magnetic spheres, dielectric–magnetic spheres with topologically insulating surface states, isotropic chiral spheres, and isotropic chiral spheres with topologically insulating surface states. The incident plane waves were taken to be linearly and circularly polarized, for the sake of illustration. Numerical results revealed that geometric-phase density plots possess significantly richer features than their counterparts for the differential scattering efficiency. The geometric-phase portrayals exhibit enhanced sensitivity to changes in the size and composition of the scatterer, the boundary conditions, and the incident polarization state, suggesting promise for inverse-scattering problems.

利用旋量代数量化庞加莱球上两个平面波位置的不相似性，应用几何相位的概念，提出了三维物体在自由空间中电磁散射的新描述。由于入射电磁场为任意极化平面波，因此使用方向相关的远区散射振幅来定义散射场的方向相关Stokes参数。建立了对称和非对称庞加莱旋量来表征入射平面波的偏振态和远区散射振幅，并由此定义了两种不同的几何相位。计算了6种具有不同线性本构性和边界条件的均匀各向同性球体的两相密度图：电介质磁球（非耗散和耗散）、阻抗球、完美导电球、带电电介质磁球、具有拓扑绝缘表面态的电介质磁球、各向同性手性球和具有拓扑绝缘表面态的各向同性手性球。为了说明，入射的平面波被认为是线性和圆偏振的。数值结果表明，几何相密度图具有比几何相密度图更丰富的差分散射效率特征。几何相位描述对散射体的大小和组成、边界条件和入射偏振态的变化表现出增强的敏感性，这表明了反散射问题的前景。

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引用次数: 0