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Surface Plasmon Resonance Enhanced scattering of Au Colloidal Nanoparticles

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Plasma Science and Technology 2003年第3期5卷 1835-1840页

作者：朱键王永昌 Institute of Modern Physics School of ScienceXi’an Jiaotong UniversityXi’an 710049ChinaInstitute of Modern PhysicsSchool of ScienceXi’an Jiaotong UniversityXi’an 710049China

Suspended gold nanoparticles have been synthesized via electrochemical method. The strongest resonance scattering peak is at 485 nm, which results from the surface plasmon resonance. When the excited wavelength is at 242 nm (12.4 × 1014 Hz), there have been a 1/2 fraction frequency scattering peak at 485 nm (1/2 × 12.4 × 1014 Hz) and a 1/3 fraction frequency scattering peak at 726 nm (1/3 × 12.4 × 1014 Hz) displayed. Emission spectra with different particle diameters were compared, the intensity of scattering light increases with the particle size. The frequency-dependent scattering average cross section of small particle was calculated from Mie theory. The model calculation is in agreement with the experimental results.

关键词： plasmon resonance Au colloidal nanoparticles light scattering

Multipath dispersion of pulse signals in a non-line-of-sight optical scattering channel

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Chinese Optics Letters 2006年第11期4卷 633-635页

作者：冯涛陈刚方祖捷 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800

Multipath-induced pulse broadening in a non-line-of-sight （NLOS） optical scattering channel is investigated. Expressions for impulse response and digital signal-to-noise ratio （DSNR） penalty induced by intersymbol interference （ISI） of a NLOS ultraviolet （UV） scattering communication are introduced based on a single-scattering model, and simulated results for some typical atmospheric condition and configuration of geometry are given in the paper. It is shown that the multipath dispersion is one of the most important factors limiting the system performances, and return-to-zero （RZ） format is more suitable for the optical scattering communications than non-return-to-zero （NRZ） format. The method proposed here can be used to predict available bandwidth and data rate of the communication system operating in a NLOS optical scattering channel. OCIS codes： 060.4510, 290.1310, 060.5530.

关键词： Bandwidth Communication systems Impulse response light scattering Signal to noise ratio

Material optimization for low scattering noise duringnonvolatile holographic recording indoubly doped LiNbO_3 crystals

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Chinese Optics Letters 2004年第11期2卷 630-633页

作者：刘德安刘立人任立勇栾竹周煜 Shanghai Institute of Optics and Fine Mechanics

scattering noises in four kinds of lithium niobate crystals with the same double doping system, which are LiNbO3:Fe:Mn, LiNbO3:Ce:Mn, LiNbO3:Ce:Cu, and LiNbO3:Fe:Cu, are observed and compared experimentally. The results show that nonvolatile holographic recording can effectively suppress scattering noise, which mainly depends on recombination coefficients of both the shallower centers and the deeper centers. The small recombination coefficients of the shallower centers and the large recombination coefficients of the deeper centers benefit the amplification of the signal gratings and the suppression of the noise gratings. In addition, the initial seed scattering also impacts the recorded scattering noise, and the little seed scattering results in low scattering noise. The theoretical simulations are performed for confirmation. Among the four kinds of doubly doped crystals, in LiNbO3:Ce:Cu the performances of nonvolatile recording are the best with low scattering noise and high diffraction efficiency.

关键词： Cerium Copper Holographic interferometry Laser beams light scattering Lithium niobate Semiconductor doping

Theoretical Study of the Effect of Multi-Diameter Distribution on the Mie scattering Characteristics of Milk Fat

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Journal of Harbin Institute of Technology(New Series) 2015年第6期22卷 115-120页

作者： Jinying Yin Siqi Zhang Hongyan Yang Zhen Zhou School of Measurement and Communication Harbin University of Science & Technology

To correct the light scattering property parameters of milk fat for improving the detection accuracy,the Mie-theory was used to establish a predictive model for light scattering properties of milk fat globule with multi-diameter distributions, by means of Monte Carlo approach to simulate actual multi-diameter size distribution of milk fat globule in milk fat solution. scattering coefficient and absorption coefficient of multidiameter distribution milk fat particles were calculated by simulating the particles size distribution in milk fat solution. And the light scattering properties of multi-diameter distribution was compared with that of volume mean diameter,Sauter mean diameter and numerical mean diameter in milk fat solution. Theoretical simulation results indicate that the scattering coefficient and absorption coefficient of milk fat particles are determined by the particle size distribution in milk fat solution. There is a distinct difference in scattering characteristics between the milk fat particles with multi-diameter distribution and that with mean diameters. Compared to that with multi-diameter distribution,the scattering coefficient of the milk fat particles with mean diameter has a maximum mean deviation of 9042 m-1. The particle size distribution is not completely determined by the mean diameters. The dependence of the light scattering properties on the particle size distribution should be considered into the model and simulation. Therefore,it is found that the particle size distribution in milk fat solution is an essential and critical factor to significantly improve the detection accuracy of milk fat content.

关键词： light scattering particle size distribution mie-theory milk fat globule

Retrieving structural information from scattering and attenuation data of transparent wood and(Nano)paper

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Journal of Bioresources and Bioproducts 2021年第3期6卷 187-194页

作者： Yoshiharu Nishiyama Univ.Grenoble Alpes CNRSCERMAVGrenoble38000France

Over the last 15 years,significant number of reports on transparent paper and transparent wood appeared in the *** light scattering data or transmission data are often given to describe the optical performance of the *** addition,the data also contains structural information that can be further analyzed based on scattering *** of the data are re-analyzed herein from structural analysis point of view related to the scattering *** analysis on the wavelength dependent optical density of nanopaper suggested that the scatterers are not isolated voids or microfibrils but rather large submicrometric and structural *** dependence of transparent wood scattering suggests the scattering units of a few micrometers such as cell wall are at the origin of high haze.

关键词： light scattering Transparent wood Nanocellulose

Rendering discrete participating media using geometrical optics approximation

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Computational Visual Media 2022年第3期8卷 425-444页

作者： Jie Guo Bingyang Hu Yanjun Chen Yuanqi Li Yanwen Guo Ling-Qi Yan State Key Lab for Novel Software Technology Nanjing UniversityNanjing 210023China Department of Computer Science UC Santa BarbaraUSA

We consider the scattering of light in participating media composed of sparsely and randomly distributed discrete *** particle size is expected to range from the scale of the wavelength to several orders of magnitude greater,resulting in an appearance with distinct graininess as opposed to the smooth appearance of continuous *** fundamental issue in the physically-based synthesis of such appearance is to determine the necessary optical properties in every local *** these properties vary spatially,we resort to geometrical optics approximation(GOA),a highly efficient alternative to rigorous Lorenz–Mie theory,to quantitatively represent the scattering of a single *** enables us to quickly compute bulk optical properties for any particle size *** then use a practical Monte Carlo rendering solution to solve energy transfer in the discrete participating *** proposed framework is the first to simulate a wide range of discrete participating media with different levels of graininess,converging to the continuous media case as the particle concentration increases.

关键词： light scattering geometrical optics approximation(GOA) discrete participating media volume rendering

CHARACTERIZATION OF MOLECULAR MASS OF SIX WATER-SOLUBLE POLYSACCHARIDE -PROTEIN COMPLEXES FROM GANODERMA TSUGAE MYCELIUM

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Chinese Journal of Polymer Science 2003年第3期21卷 309-316页

作者：张俐娜 Department of Chemistry Wuhan University Wuhan 430072 China

Six water-soluble polysaccharide-protein complexes coded as GM1, GM2, GM3, GM4, GM5 and GM6 wereisolated from the mycelium of Ganoderma tsugae by extracting with 0.2 mol/L phosphate buffer solution at 25, 40 and80℃, water at 120℃, 0.5 mol/L aqueous NaOH solution at 25 and 65℃, consecutively. Their chemical components wereanalyzed by using IR, GC, HPLC and ^(13)C-NMR, and some new results were obtained. The four samples GM1, GM2, GM3and GM4 are heteropolysaccharide-prote in complexes, in which, α- (1→3) linked D-glucose is the major monosaccharidewhile galactose, mannose and ribose are the secondary ones. GM5 and GM6 are β-(1→3)-D-glucan-protein complexes. Theprotein content increased from 32% to 69% with the progress of isolation. Weight-average molecu1ar mass M_w and theintrinsic viscosity [η] of the GM samples in 0.5 mol/L aqueous NaCl solution at 25℃ were measured systematically by laserlight scartering (LLS), size exclusion chromatography (SEC) combined with LLS, and viscometry. The M_w of GM1 to GM6are 35.5, 46.8, 58.9, 41.6, 3.3 and 22.0×10~4, respectively. The conformation and molecular mass of the two fractions of sample GM5 were characterized satisfactorily by SEC-LLS without further fractionation.

关键词： Ganoderma tsugae mycelium Polysaccharide-protein complex Chemica1 component Molecular mass light scattering Size exclusion chromatography

Unidirectional emissions from dielectric photonic circuits decorated with plasmonic phased antenna arrays

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Chinese Physics B 2014年第3期23卷 482-488页

作者：丁伟陈宇辉李志远 Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences

Thanks to resonant characteristics of metallic nanoparticles, optical waves scattered from plasmonic nanoantennae can be well tailored in both amplitude and phase. We numerically demonstrate that, by varying the lengths and the lateral positions of gold nanorods in vicinity of a silicon waveguide, unidirectional emissions with typical forward-backward contrast ratio of 15 dB and directivity of 12 dB can be acquired in a plasmonic phased antenna array with sub-wavelength device length. The properties, i.e., the emission directionality and the size compactness, can be employed to control the far-field radiation pattern from a dielectric photonic circuit. Moreover, by altering the orientations of the dielectric waveguides decorated with plasmonic phased antenna arrays, we propose wireless light transportations in a layered photonic infrastructure, which may have applications in high-density photonic integrations.

关键词： surface plasmons optical properties of nanoparticles optical structures light scattering

Measurement and characterization of bulk nanobubbles by nanoparticle tracking analysis method

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Journal of Hydrodynamics 2022年第6期34卷 1121-1133页

作者： Xiao-tong Ma Ming-bo Li Chao Sun Center for Combustion Energy Key Laboratory for Thermal Science and Power Engineering of Ministry of EducationDepartment of Energy and Power EngineeringTsinghua UniversityBeijing100084China

The size of the bulk nanobubbles(typically 100 nm-200 nm in diameter)is below the optical resolution of the typical microscopes,which makes it difficult to make a direct observation of them and differentiate between the nanoparticles and the *** this work,a nanoparticle tracking analysis(NTA)system is developed for tracking and sizing the bulk nanobubbles,and more broadly,the Brownian diffusing *** demonstrate the capabilities of the NTA in characterizing the nanoparticles through systematic validation of accuracy and *** particularly exhibit its unique advantages in detecting the polydisperse nanoparticle *** the nucleation and the thermodynamic stability of the bulk nanobubbles are systematically studied by the NTA *** bulk nanobubbles smaller than 600 nm in size are generated via the ultrasonication *** is shown that both the ultrasonic cavitation treatment time and amplitude,essentially,the energy input,favor the nucleation of the bulk nanobubbles with a more concentrated size distribution,a higher concentration,and a smaller hydrodynamic *** temperature dependence of the bulk nanobubbles over a wide range from 25°C to 70°C is *** is found that the nanobubble first shrinks in size significantly and then the size keeps approximately constant with the increasing temperature,showing a narrow size *** transition temperature is around 45°***,as an open system,the NTA is a potential tool in the study of the dynamic behavior of the bulk nanobubbles in situ,such as the coalescence and the collapse.

关键词： Nanoparticle tracking analysis bulk nanobubble light scattering hydrodynamic size number concentration