Application of global rainbow technique in sprays with a dependence of the refractive index on droplet size

Abstract Laboratory experiments were conducted in the Mainz vertical wind tunnel to study the effects of pollutants dissolved or suspended in cloud droplets on the droplet size measurements of a Forward Scattering Spectrometer Probe (FSSP). The FSSP is a widely used instrument to derive microphysical properties of atmospheric clouds. Individual droplets of different well-defined sizes were freely falling at their terminal velocities in the wind tunnel while the intensity of radiation emitted by the He–Ne laser of the FSSP and scattered by the droplets was measured. For this purpose, the FSSP was adapted and mounted to the wind tunnel. The intensity of radiation scattered by the droplets in the FSSP measurement is principally used to derive the droplet size. The droplets contained soluble ammonium sulfate or suspended absorbent graphite particles as pollutants in concentrations that were higher than usually found in atmospheric cloud droplets. The results of the measurements and corresponding simulations indicate that for high pollutant concentrations, the scattered laser radiation detected by the FSSP depends significantly on the refractive index of the droplet (i.e., on the concentration of soluble or insoluble pollutants). However, for the lower pollutant concentrations usually observed in atmospheric cloud droplets, the need for correcting the droplet sizes measured with the FSSP for the effects of the pollutions can be avoided.

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Removal of alizarin red from aqueous solution by ethyl acetate green nanoemulsions

Water Science & Technology ◽

10.2166/wst.2014.400 ◽

2014 ◽

Vol 70 (9) ◽

pp. 1569-1574 ◽

Cited By ~ 3

Author(s):

Faiyaz Shakeel ◽

Nazrul Haq ◽

Fars K. Alanazi ◽

Ibrahim A. Alsarra

Keyword(s):

Aqueous Solution ◽

Refractive Index ◽

Ethylene Glycol ◽

Ethyl Acetate ◽

Removal Efficiency ◽

Droplet Size ◽

Thermodynamic Stability ◽

Contact Time ◽

Alizarin Red ◽

Negligible Influence

The objective of the present study was to develop ethyl acetate (EA) green nanoemulsions for removal of alizarin red (AR) from water. Developed formulations were characterized in terms of thermodynamic stability, self-nanoemulsification efficiency, droplet size, polydispersity, viscosity, refractive index and per cent transmittance. Adsorption studies were performed by mixing small amounts of green nanoemulsions (1 ml) with relatively large amounts of AR solution (10 ml). It was observed that the droplet size, viscosity and % AR removal efficiency were influenced significantly by EA concentration of green nanoemulsions. However, contact time had negligible influence on % AR removal. Based on lowest droplet size (21.3 nm), lowest viscosity (19.3 Pa.s) and highest % AR removal efficiency (72.5%), green nanoemulsion E1 containing 4.0% w/w of EA, 16.0% w/w of Triton-X100, 8.0% w/w of ethylene glycol and 72% w/w of water was optimized as the best green nanoemulsion composition for removal of AR from its bulk aqueous solution.

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Vitamin E Loaded Naringenin Nanoemulsion via Intranasal Delivery for the Management of Oxidative Stress in a 6-OHDA Parkinson’s Disease Model

BioMed Research International ◽

10.1155/2019/2382563 ◽

2019 ◽

Vol 2019 ◽

pp. 1-20 ◽

Cited By ~ 17

Author(s):

Bharti Gaba ◽

Tahira Khan ◽

Md Faheem Haider ◽

Tausif Alam ◽

Sanjula Baboota ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Refractive Index ◽

Vitamin E ◽

Zeta Potential ◽

Droplet Size ◽

Disease Model ◽

Intranasal Delivery ◽

Behavioral Studies ◽

Swimming Test

Purpose. The present study is an attempt to develop a vitamin E loaded naringenin (NRG) Nanoemulsion (NE) for direct nose-to-brain delivery for better management of Parkinson's disease (PD). Methods. The optimized NE was evaluated for efficacy in PD using multiple behavioral studies (including narrow beam test, muscular coordination test, grip strength test, forced swimming test, and akinesia test) in a rat model. Optimized formulation was evaluated for droplet size, polydispersity index (PDI), refractive index, transmittance, zeta potential, and viscosity. Results. Optimized NE had a droplet size of 38.70 ± 3.11nm, PDI of 0.14 ± 0.0024, refractive index of 1.43 ± 0.01, transmittance of 98.12 ± 0.07 %, zeta potential of − 27.4 ± 0.14 mV, and viscosity of 19.67 ± 0.25 Pa s. Behavioral studies showed that 6-OHDA induced PD in rats were successfully reversed when administered with NRG NE intranasally along with the levodopa. While the levels of GSH and SOD were significantly higher, levels of MDA were significantly lower in the group treated with NRG NE via intranasal route along with levodopa. Conclusion. Encouraging results from current study provide evidence for possible efficacy of a novel noninvasive intranasal delivery system of NRG for management of PD related symptoms.

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Refractive Index of the Dispersed Phase in Oil-in-Water Emulsions: Its Dependence on Droplet Size and Aging

Journal of Food Science ◽

10.1111/j.1365-2621.1983.tb10778.x ◽

1983 ◽

Vol 48 (2) ◽

pp. 513-516 ◽

Cited By ~ 19

Author(s):

APURBA K. RAY ◽

JOHN K. JOHNSON ◽

ROBERT J. SULLIVAN

Keyword(s):

Refractive Index ◽

Droplet Size ◽

Dispersed Phase ◽

Oil In Water

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TEM characterization of proton-exchanged LiNbO3 optical waveguides

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014395x ◽

1986 ◽

Vol 44 ◽

pp. 480-481

Author(s):

W. E. Lee

Keyword(s):

Refractive Index ◽

Benzoic Acid ◽

Optical Waveguides ◽

Total Internal Reflection ◽

Index Of Refraction ◽

Optical Measurements ◽

Lithium Ions ◽

Wide Channel ◽

Tem Characterization

An optical waveguide consists of a several-micron wide channel with a slightly different index of refraction than the host substrate; light can be trapped in the channel by total internal reflection.Optical waveguides can be formed from single-crystal LiNbO3 using the proton exhange technique. In this technique, polished specimens are masked with polycrystal1ine chromium in such a way as to leave 3-13 μm wide channels. These are held in benzoic acid at 249°C for 5 minutes allowing protons to exchange for lithium ions within the channels causing an increase in the refractive index of the channel and creating the waveguide. Unfortunately, optical measurements often reveal a loss in waveguiding ability up to several weeks after exchange.

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Light microscopy of ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015037x ◽

1993 ◽

Vol 51 ◽

pp. 908-909

Author(s):

Walter C. McCrone

Keyword(s):

Refractive Index ◽

Light Microscopy ◽

Light Microscope ◽

Polarized Light ◽

Refractive Indices ◽

Complete Coverage ◽

The Subject ◽

Lower Refractive Index

An excellent chapter on this subject by V.D. Fréchette appeared in a book edited by L.L. Hench and R.W. Gould in 1971 (1). That chapter with the references cited there provides a very complete coverage of the subject. I will add a more complete coverage of an important polarized light microscope (PLM) technique developed more recently (2). Dispersion staining is based on refractive index and its variation with wavelength (dispersion of index). A particle of, say almandite, a garnet, has refractive indices of nF = 1.789 nm, nD = 1.780 nm and nC = 1.775 nm. A Cargille refractive index liquid having nD = 1.780 nm will have nF = 1.810 and nC = 1.768 nm. Almandite grains will disappear in that liquid when observed with a beam of 589 nm light (D-line), but it will have a lower refractive index than that liquid with 486 nm light (F-line), and a higher index than that liquid with 656 nm light (C-line).

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