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Fluent 1

Mie散射 1

PEDOT:PSS 1

ToF）；散射介质；拐角遮挡 1

切伦柯夫探测器 1

后处理 1

图像散射；边缘增强；卷积神经网络；非下采样轮廓波变换 1

声辐射和散射 1

多散射中心 1

子波分析 1

扩展的Prony算法 1

掠入射广角X射线散射 1

散射 1

散射吸收法 1

步进频率信号 1

波浪力 1

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Largely reduced cross-plane thermal conductivity of nanoporous In

Dongchao XU, Quan WANG, Xuewang WU, Jie ZHU, Hongbo ZHAO, Bo XIAO, Xiaojia WANG, Xiaoliang WANG, Qing HAO

《能源前沿（英文）》 2018年第12卷第1期页码 127-136 doi: 10.1007/s11708-018-0519-5

摘要： In recent year, nanoporous Si thin films have been widely studied for their potential applications in thermoelectrics, in which high thermoelectric performance can be obtained by combining both the dramatically reduced lattice thermal conductivity and bulk-like electrical properties. Along this line, a high thermoelectric figure of merit (ZT) is also anticipated for other nanoporous thin films, whose bulk counterparts possess superior electrical properties but also high lattice thermal conductivities. Numerous thermoelectric studies have been carried out on Si-based nanoporous thin films, whereas cost-effective nitrides and oxides are not systematically studied for similar thermoelectric benefits. In this work, the cross-plane thermal conductivities of nanoporous In Ga N thin films with varied porous patterns were measured with the time-domain thermoreflectance technique. These alloys are suggested to have better electrical properties than conventional Si Ge alloys; however, a high ZT is hindered by their intrinsically high lattice thermal conductivity, which can be addressed by introducing nanopores to scatter phonons. In contrast to previous studies using dry-etched nanopores with amorphous pore edges, the measured nanoporous thin films of this work are directly grown on a patterned sapphire substrate to minimize the structural damage by dry etching. This removes the uncertainty in the phonon transport analysis due to amorphous pore edges. Based on the measurement results, remarkable phonon size effects can be found for a thin film with periodic 300-nm-diameter pores of different patterns. This indicates that a significant amount of heat inside these alloys is still carried by phonons with ~300 nm or longer mean free paths. Our studies provide important guidance for ZT enhancement in alloys of nitrides and similar oxides.

关键词： nanoporous film thermoelectrics phonon mean free path diffusive scattering

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Radiative properties of materials with surface scattering or volume scattering: A review

Qunzhi ZHU, Hyunjin LEE, Zhuomin M. HANG

《能源前沿（英文）》 2009年第3卷第1期页码 60-79 doi: 10.1007/s11708-009-0011-3

摘要： Radiative properties of rough surfaces, particulate media and porous materials are important in thermal engineerit transfer between surfaces and volume elements in participating media, as well as for accurate radiometric temperature measurements. In this paper, recent research on scattering of thermal radiation by rough surfaces, fibrous insulation, soot, aerogel, biological materials, and polytetrafluoroethylene (PTFE) was reviewed. Both theoretical modeling and experimental investigation are discussed. Rigorous solutions and approximation methods for surface scattering and volume scattering are described. The approach of using measured surface roughness statistics in Monte Carlo simulations to predict radiative properties of rough surfaces is emphasized. The effects of various parameters on the radiative properties of particulate media and porous materials are summarized.

关键词： aerogel fiber particle scattering radiative properties soot surface roughness

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Effect of light scattering on the performance of a direct absorption solar collector

Kwang Hyun WON, Bong Jae LEE

《能源前沿（英文）》 2018年第12卷第1期页码 169-177 doi: 10.1007/s11708-018-0527-5

摘要： Recently, a solar thermal collector often employs nanoparticle suspension to absorb the solar radiation directly by a working fluid as well as to enhance its thermal performance. The collector efficiency of a direct absorption solar collector (DASC) is very sensitive to optical properties of the working fluid, such as absorption and scattering coefficients. Most of the existing studies have neglected particle scattering by assuming that the size of nanoparticle suspension is much smaller than the wavelength of solar radiation (i.e., Rayleigh scattering is applicable). If the nanoparticle suspension is made of metal, however, the scattering cross-section of metallic nanoparticles could be comparable to their absorption cross-section depending on the particle size, especially when the localized surface plasmon (LSP) is excited. Therefore, for the DASC utilizing a plasmonic nanofluid supporting the LSP, light scattering from metallic particle suspension must be taken into account in the thermal analysis. The present study investigates the scattering effect on the thermal performance of the DASC employing plasmonic nanofluid as a working fluid. In the analysis, the Monte Carlo method is employed to numerically solve the radiative transfer equation considering the volume scattering inside the nanofluid. It is found that the light scattering can improve the collector performance if the scattering coefficient of nanofluid is carefully engineered depending on its value of the absorption coefficient.

关键词： direct absorption solar collector plasmonic nanofluid light scattering

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Diffusive gradients in thin films using molecularly imprinted polymer binding gels for in situ measurements

Ying Cui, Feng Tan, Yan Wang, Suyu Ren, Jingwen Chen

《环境科学与工程前沿（英文）》 2020年第14卷第6期 doi: 10.1007/s11783-020-1290-5

摘要： Abstract • Selective molecularly imprinted polymer (MIP) binding gel was prepared. • MIP-DGT showed excellent uptake performance for antibiotics. • In situ measurement of antibiotics in wastewaters via MIP-DGT was developed. • The MIP-DGT method was robust, reliable, and highly sensitive. Urban wastewater is one of main sources for the introduction of antibiotics into the environment. Monitoring the concentrations of antibiotics in wastewater is necessary for estimating the amount of antibiotics discharged into the environment through urban wastewater treatment systems. In this study, we report a novel diffusive gradient in thin films (DGT) method based on molecularly imprinted polymers (MIPs) for in situ measurement of two typical antibiotics, fluoroquinolones (FQs) and sulfonamides (SAs) in urban wastewater. MIPs show specific adsorption toward their templates and their structural analogs, resulting in the selective uptake of the two target antibiotics during MIP-DGT deployment. The uptake performance of the MIP-DGTs was evaluated in the laboratory and was relatively independent of solution pH (4.0–9.0), ionic strength (1–750 mmol/L), and dissolved organic matter (DOM, 0–20 mg/L). MIP-DGT samplers were tested in the effluent of an urban wastewater treatment plant for field trials, where three SA (sulfamethoxazole, sulfapyridine, and trimethoprim) and one FQ (ofloxacin) antibiotics were detected, with concentrations ranging from 25.50 to 117.58 ng/L, which are consistent with the results measured by grab sampling. The total removal efficiency of the antibiotics was 80.1% by the treatment plant. This study demonstrates that MIP-DGT is an effective tool for in situ monitoring of trace antibiotics in complex urban wastewaters.

关键词： Diffusive gradients in thin films Molecularly imprinted polymers Selective uptake Antibiotics Passive sampling

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火灾烟雾颗粒的光学散射特性研究

疏学明,方俊,邵荃,袁宏永

《中国工程科学》 2005年第7卷第1期页码 45-49

摘要：

从理论和实验两个方面研究了几种常见的燃烧烟雾在不同波长激光下的散射特性。从Mie散射理论出发，比较几种Mie散射算法的优缺点，采用一种改进的连分式算法对火灾烟雾颗粒的散射光强分布进行计算，得出不同粒径大小和波长下光强分布图。结合理论计算，设计一套实验装置，测量并计算在不同角度下3种烟雾颗粒和面粉气溶胶散射光的相对光强比，实验测量值与理论计算值吻合较好。研究结果表明不同种类烟雾散射光相对光强比互不相同，火灾烟雾与非烟雾气溶胶差距较大，从而表明散射光相对光强比是区分不同烟雾特定的物性参数，为火灾烟雾探测技术发展提供理论依据。

关键词：火灾烟雾 Mie散射算法相对光强比

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基于去散射与边缘增强算法的水下图像复原 Research Papers

Pan-wang PAN, Fei YUAN, En CHENG

《信息与电子工程前沿（英文）》 2019年第20卷第6期页码 862-871 doi: 10.1631/FITEE.1700744

摘要：对色差严重和边缘模糊的水下图像需进行复原。一般分两步：去散射和边缘增强。首先，提出一种用于水下图像去散射的多尺度迭代框架。利用卷积神经网络估计传输图，再用自适应双边滤波器改进传输图估计结果。由于无可用数据集训练网络，收集包含2000个水下图像的数据集以获得合成数据。其次，采用白平衡算法消除水下图像的色偏。最后将图像转换到特殊变换域，使用非下采样轮廓波变换对边缘去噪和增强。结果表明：该方法主、客观质量均明显优于现有方法。

关键词：图像散射；边缘增强；卷积神经网络；非下采样轮廓波变换

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子波分析在声辐射和声散射中的应用

文立华,任兴民

《中国工程科学》 2002年第4卷第8期页码 63-68

摘要：

文章提出将子波分析用于求解声学中的边界积分方程，能提高现有边界元方法解决工程问题的能力。在子波分析于声辐射和声散射的应用研究中，提出了把积分核函数用级数展开，建立频率响应函数计算的频率迭代技术，大大提高了频率响应函数的计算效率。讨论了子波分析在声学工程数值计算中的研究前景。

关键词：子波分析声辐射和散射结构声耦合频率响应函数

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Molecular diffusion in ternary poly(vinyl alcohol) solutions

《化学科学与工程前沿（英文）》 2022年第16卷第6期页码 1003-1016 doi: 10.1007/s11705-021-2121-3

摘要： The diffusion kinetics of a molecular probe—rhodamine B—in ternary aqueous solutions containing poly(vinyl alcohol), glycerol, and surfactants was investigated using fluorescence correlation spectroscopy and dynamic light scattering. We show that the diffusion characteristics of rhodamine B in such complex systems is determined by a synergistic effect of molecular crowding and intermolecular interactions between chemical species. The presence of glycerol has no noticeable impact on rhodamine B diffusion at low concentration, but significantly slows down the diffusion of rhodamine B above 3.9% (w/v) due to a dominating steric inhibition effect. Furthermore, introducing surfactants (cationic/nonionic/anionic) to the system results in a decreased diffusion coefficient of the molecular probe. In solutions containing nonionic surfactant, this can be explained by an increased crowding effect. For ternary poly(vinyl alcohol) solutions containing cationic or anionic surfactant, surfactant–polymer and surfactant–rhodamine B interactions alongside the crowding effect of the molecules slow down the overall diffusivity of rhodamine B. The results advance our insight of molecular migration in a broad range of industrial complex formulations that incorporate multiple compounds, and highlight the importance of selecting the appropriate additives and surfactants in formulated products.

关键词： fluorescence correlation spectroscopy poly(vinyl alcohol) anomalous diffusion crowding effects dynamic light scattering binding effects rhodamine B

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Shape reconstruction of parallelogram flaw

ZHENG Gangfeng, WU Bin, HE Cunfu

《机械工程前沿（英文）》 2008年第3卷第1期页码 17-22 doi: 10.1007/s11465-008-0015-4

摘要： To reconstruct the shape of the scatterer in elastic media, the authors deduce the Born approximation solution of the two-dimensional scattering problem, which includes the shape factor that embodies all information about the shape of the scatterer. Accordingly, the change in the shape of the scatterer only necessitates the number of the corresponding new shape factors. For a parallelogram void in a long Al rod, its shape factor can be obtained. In view of the definition of a characteristic function, the shape factor has a corresponding integral representation. Obviously, the shape factor can be considered as a Fourier transform of the characteristic function, which is reconstructed from the inverse Fourier transform. The integral equation is considered as the basic equation to reconstruct the shape of the scatterer. The identification of the geometrical character of a flaw is then given by the two dimensional inverse Born approximation in a low-frequency range. For the parallelogram void, a theoretical calculating identification is performed. At the same time, the numerical results are obtained by the finite element method.

关键词： approximation scatterer scattering problem information inverse

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SERS nanoprobes for bio-application

Han-Wen Cheng,Jin Luo,Chuan-Jian Zhong

《化学科学与工程前沿（英文）》 2015年第9卷第4期页码 428-441 doi: 10.1007/s11705-015-1536-0

摘要： The ability to tune the size, shape, composition and surface properties impart nanoparticles with the desired functions for bio-application. This article highlights some of the recent examples in the exploration of metal (e.g., gold and silver) nanoparticles, especially those with magnetic properties and bio-conjugated structures, as theranostic nanoprobes. Such nanoprobes exhibit tunable optical, spectroscopic, magnetic, and electrical properties for signal amplifications. Examples discussed in this article will focus on the nanoproble-enhanced colorimetric detection and surface enhanced Raman scattering (SERS) detection of biomarkers or biomolecules such as proteins and DNAs. The understanding of factors controlling the biomolecular interactions is essential for the design of SERS nanoprobes with theranostic functions.

关键词： surface-enhanced Raman scattering functional nanoprobes bio-conjugation metal nanoparticles magnetic properties theranostic materials

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Photothermal-Management Agricultural Films toward Industrial Planting: Opportunities and Challenges

Song Zhang,Zhang Chen,Chuanxiang Cao,Yuanyuan Cui,Yanfeng Gao,

《工程（英文）》 doi: 10.1016/j.eng.2023.06.016

摘要： As indispensable parts of greenhouses and plant factories, agricultural covering films play a prominent role in regulating microclimate environments. Polyethylene covering films directly transmit the full solar spectrum. However, this high level of sunlight transmission may be inappropriate or even harmful for crops with specific photothermal requirements. Modern greenhouses are integrated with agricultural covering materials, heating, ventilation, and air conditioning (HVAC) systems, and smart irrigation and communication technologies to maximize planting efficiency. This review provides insight into the photothermal requirements of crops and ways to meet these requirements, including new materials based on passive radiative cooling and light scattering, simulations to evaluate the energy consumption and environmental conditions in a greenhouse, and data mining to identify key biological growth factors and thereby improve new covering films. Finally, future challenges and directions for photothermal-management agricultural films are elaborated on to bridge the gap between lab-scale research and large-scale practical applications.

关键词： Greenhouse Photothermal management Passive radiative cooling Light scattering

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Multi-functional 3D N-doped TiO

Zijian Cui, Kaiyue Zhang, Guangyu Xing, Yaqing Feng, Shuxian Meng

《化学科学与工程前沿（英文）》 2017年第11卷第3期页码 395-404 doi: 10.1007/s11705-017-1643-1

摘要： Three-dimensional TiO microspheres doped with N were synthesized by a simple single-step solvothermal method and the sample treated for 15 h (hereafter called TMF) was then used as scattering layers in the photoanodes of dye-sensitized solar cells (DSSCs). The TMF was characterized using scanning electron microscopy, high resolution transmission electron microscopy, Brunauer-Emmett-Teller measurements, X-ray diffraction, and X-ray photoelectron spectroscopy. The TMF had a high surface area of 93.2 m ·g which was beneficial for more dye-loading. Five photoanode films with different internal structures were fabricated by printing different numbers of TMF scattering layers on fluorine-doped tin oxide glass. UV-vis diffuse reflection spectra, incident photon-to-current efficiencies, photocurrent-voltage curves and electrochemical impedance spectroscopy were used to investigate the optical and electrochemical properties of these photoanodes in DSSCs. The presence of nitrogen in the TMF changed the TMF microstructure, which led to a higher open circuit voltage and a longer electron lifetime. In addition, the presence of the nitrogen significantly improved the light utilization and photocurrent. The highest photoelectric conversion efficiency achieved was 8.08%, which is much higher than that derived from typical P25 nanoparticles (6.52%).

关键词： DSSCs N doping scattering layer electron lifetime

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Prony算法在步进频率雷达多目标检测中的建模研究

胡体玲,李兴国

《中国工程科学》 2008年第10卷第10期页码 67-71

摘要：

步进频率信号是一种以增大信号带宽为代价来提高雷达距离分辨力的宽带信号。在步进频率雷达中，将接收的基带信号看作是包含目标信息的指数函数的线性组合；而Prony 算法是用指数函数的一组线性组合来描述等间距采样数据的数学模型。将扩充的Prony算法应用到步进频率体制的雷达中，可以得到更为精确的目标信息，并且可以克服直接采用IDFT合成高分辨距离像的一些缺点。相应的建模分析和实验仿真，说明了该算法的优越性。

关键词：高分辨雷达步进频率信号扩展的Prony算法多散射中心

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细水雾与热烟气相互作用数值模拟研究

叶栋,蒋勇

《中国工程科学》 2007年第9卷第2期页码 84-89

摘要：

使用CFD软件Fluent对火灾中热烟气与细水雾的相互作用过程进行了数值模拟研究。比较了灭火过程中不同粒径细水雾在流场中的运动及其对灭火效果的影响，并研究了细水雾对着火房间火焰辐射的散射作用及细水雾的聚合破碎过程对灭火效果的影响。模拟结果表明辐射是火灾中主要的热传递过程，粒径较大的水雾比较容易离开回流区到达燃烧反应区。房间细水雾的通过吸收和散射作用减弱辐射强度，水雾在喷射初期可能使燃烧速率增大，这些结果与实验事实相符

关键词：细水雾 Fluent 热辐射散射聚合破碎

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柱形地形上单浮体的辐射和散射问题

吴必军,郑永红,游亚戈,孙晓燕,陈勇

《中国工程科学》 2004年第6卷第2期页码 48-55

摘要：

在有限水深、同轴但半径大于或等于浮体半径的圆柱体障碍物地形条件下，基于特征函数展开法，推导了垂直放置的圆柱形浮体由于波的辐射和散射作用所表现的动力学和运动学特征表达式，涉及浮体做垂荡、横荡和横摇运动所产生的辐射势，以及在入射波的作用下，由于浮体固定不动而产生的散射势，并推导了激励力、附加质量和阻尼系数表达式。采用与同轴、同半径圆柱体障碍物地形上单浮体水动力学特性相比的方式和激励力计算两种方法验证了推导的表达式，最后分析了障碍物几何尺寸对浮体水动力学特性的特有影响。

关键词：解析方法速度势波浪力