Two-Dimensional Radiative Back-Scattering From Optically Thick Media

1986 ◽  
Vol 108 (3) ◽  
pp. 619-625 ◽  
Author(s):  
H. F. Nelson ◽  
D. C. Look ◽  
A. L. Crosbie
Keyword(s):  
Laser Beam ◽  
Scattered Radiation ◽  
Water Solution ◽  
Index Of Refraction ◽  
Isotropic Scattering ◽  
Scattering Medium ◽  
Back Scattering ◽  
Scattering Centers ◽  
Optical Radius ◽  
Good Agreement

The theoretical and experimental results of anisotropic back-scattering from an optically thick medium exposed to a laser beam are presented. The laser beam is incident normal to the upper surface of the scattering medium. Uniformly sized latex particles with diameters ranging from 0.046 to 0.35 μm are used for the scattering centers in a water solution. The results are discussed for back-scattered radiation as a function of optical radius from the laser beam and optical thickness of the scattering medium. It is shown that back-scattered radiation in optically thick media is very sensitive to small changes in albedo when the albedo is near unity. The sensitivity increases as the optical radius increases. Also, the isotropic scattering solution yields good agreement with the experimental data at large optical radii when one uses effective optical properties. The agreement between theory and experiment is improved when index of refraction effects at the interface are included.

Anisotropic Two-Dimensional Scattering: Comparison of Experiment with Theory

1981 ◽  
Vol 103 (1) ◽  
pp. 127-134 ◽  
Author(s):  
D. C. Look ◽  
H. F. Nelson ◽  
A. L. Crosbie
Keyword(s):  
Laser Beam ◽  
Water Solution ◽  
Anisotropic Scattering ◽  
Infinite Medium ◽  
Isotropic Scattering ◽  
Asymmetry Factor ◽  
Two Dimensional ◽  
Scattering Media ◽  
Uniform Size ◽  
Scattering Centers

Anisotropic scattering from a semi-infinite medium exposed to a laser beam is studied. The situation is two-dimensional and cylindrical because the laser beam is incident normal to the purely scattering media. The back scattered radiation in the normal direction is predicted and measured as a function of the distance from the beam. The latex particles of uniform size with diameters ranging from 0.03 up to 1.011 μ are used as scattering centers in a water solution. The influence of anisotropic scattering shifts the maximum of the radial distribution of the scattered intensity to larger optical radii as the particle size increases. For large optical thicknesses, the asymmetry factor is used as a correlation coefficient to reduce the anisotropic results to those of isotropic scattering.

scholarly journals Laboratory Measurements of Light Scattering by Dust Particles

1996 ◽  
Vol 150 ◽  
pp. 409-413
Author(s):  
Patrick P. Combet ◽  
Philippe L. Lamy
Keyword(s):  
Light Scattering ◽  
Laser Beam ◽  
Mie Theory ◽  
Spherical Particles ◽  
Dust Particles ◽  
Laboratory Measurements ◽  
Scattering Function ◽  
Hene Laser ◽  
Set Up ◽  
Good Agreement

AbstractWe have set up an experimental device to optically study the scattering properties of dust particles. Measurements over the 8 — 174° interval of scattering angles are performed on a continuously flowing dust loaded jet illuminated by a polarized red HeNe laser beam. The scattering is averaged over the population of the dust particles in the jet, which can be determined independently, and give the “volume scattering function” for the two directions of polarization directly. While results for spherical particles are in good agreement with Mie theory, those for arbitrary particles show conspicuous deviations.

Laser beam focusing through the scattering medium by means of adaptive optics

2017 ◽  
Author(s):  
Ilya Galaktionov ◽  
Alexis Kudryashov ◽  
Julia Sheldakova ◽  
Alexander Nikitin
Keyword(s):  
Laser Beam ◽  
Adaptive Optics ◽  
Scattering Medium ◽  
Beam Focusing

scholarly journals A Monte-Carlo Simulation of the Behaviour of Electron Swarms in Hydrogen Using an Anisotropic Scattering Model

1978 ◽  
Vol 31 (4) ◽  
pp. 299 ◽  
Author(s):  
HA Blevin ◽  
J Fletcher ◽  
SR Hunter
Keyword(s):  
Experimental Data ◽  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Electron Transport ◽  
Anisotropic Scattering ◽  
Isotropic Scattering ◽  
Transport Parameters ◽  
Simulation Code ◽  
Scattering Model ◽  
Good Agreement

Hunter (1977) found that a Monte-Carlo simulation of electron swarms in hydrogen, based on an isotropic scattering model, produced discrepancies between the predicted and measured electron transport parameters. The present paper shows that, with an anisotropic scattering model, good agreement is obtained between the predicted and experimental data. The simulation code is used here to calculate various parameters which are not directly measurable.

Biological Conjugate between Antibody and ZnS Nanoparticles as Probe for Atomic Absorption Spectrophotometry Determination of Estriol

2014 ◽  
Vol 556-562 ◽  
pp. 64-66
Author(s):  
Chun Yan Zhang ◽  
Chuan Tao Wang ◽  
Shu Hao Wang ◽  
Ling Yun Du
Keyword(s):  
Atomic Absorption ◽  
Limit Of Detection ◽  
Water Solution ◽  
Semiconductor Nanocrystals ◽  
Atomic Absorption Spectrophotometry ◽  
Serum Samples ◽  
Absorption Spectrophotometry ◽  
Primary Materials ◽  
Good Agreement

ZnS semiconductor nanocrystals (NCs) were prepared by ways from primary materials of ZnCl2 and Na2S in water solution. Using the synthesized ZnS NCs, a polyclonal antibody-based ZnS-labelled immunosorbent assay for the determination of estriol (E3) was developed with atomic absorption spectrophotometry (AAS) as a detector. An immunoaffinity column was applied to testify conjugation between antibody and ZnS NCs. The linear range for determination of estriol is 40.0~600.0 ng.mL-1, and the limit of detection (LOD) is 10.0 ng.mL-1. Some serum samples have been analyzed with satisfactory results which are in good agreement with those obtained using ELISA. This work suggests the potential application of NCs as biological probes and AAS as detector in nonisotopic immunoassay.

Instantaneous Optical Measurement of the Temperature at the Interface Between a Wall and a Thin Liquid Film

2020 ◽  
Vol 142 (12) ◽  
Author(s):  
Brian E. Fehring ◽  
Roman W. Morse ◽  
Jason Chan ◽  
Kristofer M. Dressler ◽  
Evan T. Hurlburt ◽  
...  
Keyword(s):  
Laser Beam ◽  
Liquid Film ◽  
Solid Wall ◽  
Incident Angle ◽  
Thin Liquid Film ◽  
Index Of Refraction ◽  
High Temporal Resolution ◽  
Flow Measurements ◽  
Vapor Interface ◽  
Liquid Vapor

Abstract Instantaneous temperature measurements at the interface between a solid wall and a thin, unsteady liquid film are performed using thermoreflectance, a nonintrusive optical technique with high temporal resolution. A laser beam is directed at a wall–liquid interface, and the intensity of the light reflected at that interface is measured by a photodiode. The intensity of the reflected light varies with the index of refraction of the liquid at the wall. The index of refraction is a function of temperature, which enables the instantaneous measurement of the wall temperature. In the presence of thin liquid films, reflections from the liquid–vapor interface at the free surface of the film generate noise in the measurements. We demonstrate that orienting the laser beam at a large incident angle, close to total internal reflection, minimizes noise from the liquid–vapor interface while increasing the sensitivity of the measurement. The thermoreflectance technique is validated in an unsteady two-phase annular flow. Measurements of temperature fluctuations less than 1 K in amplitude are achieved, with an uncertainty of 0.1 K.

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