scholarly journals Evaluation of Demodex mite viability using motility and scattered light intensity

2019 ◽  
Vol 77 (4) ◽  
pp. 463-469 ◽  
Author(s):  
S. Gatault ◽  
R. Foley ◽  
L. Shiels ◽  
F. C. Powell
Author(s):  
Pierre Doublet ◽  
Christine Lempereur ◽  
Virginel Bodoc ◽  
Mikael Orain ◽  
Pierre Gajan

Optical techniques are  widely employed for their non-intrusive behavior and are applied to two-phase flowinvestigations. Until now, the most commonly used technique to determine the droplet size is the Phase Doppler Anemogranulometry, although it is time consuming for an overall injector characterization. An imaging technique called Planar Droplet Sizing has been used to offer an alternative and provide a spatially-resolved 2D map of the Sauter Mean Diameter (SMD). The measurement is based on the ratio between laser-induced fluorescence and scattered light intensities which are assumed to be proportional respectively to the droplet volume and droplet surface area. However, previous studies revealed that the dependence of fluorescence intensity on the droplet volume can be altered by the absorption of light in the liquid. The scattered light intensity depends on the scattering angle and intensity variations within the field of view must be avoided.The aim of this study is to make the PDS technique operational for a Jet A-1 kerosene spray. A strong absorption of liquid kerosene appears under UV excitation at 266 nm making the technique unsuitable. Under visible excitation at 532 nm, a fluorescent tracer (Pyrromethene 597) must be added to the kerosene to enhance the fluorescence signal. To prevent scattered light intensity variations within the field of view, an optimal scattering angle close to 115° is required. An image processing algorithm is proposed in order to reduce the effects ofmultiple scattering.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4698


1980 ◽  
Vol 90 ◽  
pp. 55-60
Author(s):  
A. Mujica ◽  
G. Lôpez ◽  
F. Sánchez

SummaryA method of determination of the scattered light intensity, , by a unit-volume of interplanetary space is presented. From ground base Zodiacal Light measurements and the experimental results of Pioneer X the density, ρ(r), and phase, σ(θ), functions are obtained without any previous assumptions about them.


2005 ◽  
Vol 862 ◽  
Author(s):  
Guozhen Yue ◽  
Gautam Ganguly ◽  
Baojie Yan ◽  
Jeffrey Yang ◽  
Subhendu Guha

AbstractHydrogenated amorphous silicon (a-Si:H) solar cells incorporating high deposition rate (8-10Å/s) intrinsic layers were deposited using modified very high frequency (MVHF) plasma. We have monitored the light scattered from powder generated in the plasma using an Ar-laser and a silicon photodiode. This simple, non-invasive technique allows us to make measurements on the same reactor used to make the solar cells. First, we have varied the total flow rate and observed a maximum in the scattered light intensity from powder in the plasma during the deposition of the intrinsic layer, and correlated this with the degradation, as well as the stabilized performance of the solar cells. Then, we have studied the effects of varying the deposition temperature and/or the addition of germane to the gas mixture on the scattered light intensity due to powder in the plasma.


Author(s):  
D. W. Burr ◽  
K. J. Daun ◽  
K. A. Thomson ◽  
G. J. Smallwood

In multiangle elastic light scattering (MAELS) experiments, the morphology of aerosolized particles is inferred by shining collimated radiation through the aerosol and then measuring the scattered light intensity over a set of angles. In the case of soot-laden aerosols MAELS can be used to recover, among other things, the size distribution of soot aggregates. This involves solving an ill-posed set of equations, however. While previous work focused on regularizing the inverse problem using Bayesian priors, this paper presents a design-of-experiment methodology for identifying the set of measurement angles that minimizes its ill-posedness. The inverse problem produced by the optimal angle set requires less regularization and is less sensitive to noise, compared with two other measurement angle sets commonly used to carry out MAELS experiments.


A theory of light scattering in fluids produced by local fluctuations of refractive index is developed from the theory of X-ray scattering in fluids which is applied to the phenomena of critical opalescence in one-component liquids due to density fluctuations and in two-component liquid mixtures due to concentration fluctuations. The dependence of the scattered light intensity on wave-length and scattering angle can be derived from the theoretical expressions when the correlation of the fluctuations in two volume elements as a function of the distance of these elements is known. The theory is used for determining the shape of the correlation function for a number of binary mixtures from the measured angular distribution of the scattered light intensity, as described in part I by means of numerical computation of Fourier integrals. It is found that the mixtures belonging to class I (as defined in part I) are characterized by a correlation function with a range of negative correlation, and those belonging to class II by a correlation function of nearly Gaussian shape. The absolute magnitude of the concentration fluctuations near the critical mixing point is also calculated from the observational material. A tentative qualitative explanation for the different shapes of the correlation function for the two classes of mixtures is presented.


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