Back Cover: Cell nuclei have lower refractive index and mass density than cytoplasm (J. Biophotonics 10/2016)

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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Образование акцепторных центров в CdHgTe под воздействием воды и термообработок

Физика и техника полупроводников ◽

10.21883/ftp.2021.04.50734.9560 ◽

2021 ◽

Vol 55 (4) ◽

pp. 331

Author(s):

Г.Ю. Сидоров ◽

Ю.Г. Сидоров ◽

В.А. Швец ◽

В.С. Варавин

Keyword(s):

Refractive Index ◽

Water Treatment ◽

Epitaxial Films ◽

Heat Treatments ◽

Deionized Water ◽

Native Oxide ◽

Water Medium ◽

Native Oxide Layer ◽

Formation Heat ◽

Lower Refractive Index

Influence storage and boiling in deionized water and heat treatments of epitaxial films CdxHg1-xTe on the Hall and ellipsometric parametres is investigated. Water treatment reduces refractive index of native CdxHg1-xTe oxide from 2.1 to 1.2-1.4. It means that matter with a lower refractive index, such as water, is introduced in the oxide. Boiling in water leads to formation of acceptors in CdxHg1-xTe with concentrations up to 1019 cm-3. Change of medium’s pH from alkaline to the acidic decreases the speed of acceptors formation. Heat treatments after storage in water also leads to formation of acceptors. The conclusion is made, that water medium or water absorbed by native oxide layer leads to formation of acceptors in CdxHg1-xTe. Concentration of acceptors grows with temperature of treatments and quantity of accessible water.

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Controlling Thermoplastic Elastomer Optical Properties by Mechanical Processing

MRS Advances ◽

10.1557/adv.2019.19 ◽

2019 ◽

Vol 4 (23) ◽

pp. 1341-1347 ◽

Cited By ~ 1

Author(s):

Margaret Campbell ◽

Paramjot Singh ◽

Kunal Kate ◽

Cindy K. Harnett

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Optical Transmission ◽

Thermoplastic Elastomer ◽

Mechanical Processing ◽

Sensor Signal ◽

Extrusion Speed ◽

The Core ◽

Lower Refractive Index ◽

Urethane Elastomer

ABSTRACTWe demonstrate that the extrusion speed of thermoplastic urethane elastomer can modify its optical transmission by a factor of more than 100. Varying extrusion speed at constant temperature may tune optical properties along the axis of a filament, for example creating absorbent regions that are sensitive to length and diameter changes, surrounded by more transmissive segments that carry the sensor signal over long distances. Such waveguiding in a stretchable optical fiber requires a stretchable cladding with lower refractive index than the core. In experiments toward a rugged, stretchable fiber cladding, we investigated whether solvents could modify the outer structure of the filaments. Soaking the filaments in NMP (n-methyl-2-pyrrolidone), then stretching the filaments while the solvent dried, turned out to modify the filaments in a way that solvents alone did not, creating porosity and reducing the appearance of optical clarity.

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Thermal equilibration behind an ionizing shock

Journal of Fluid Mechanics ◽

10.1017/s0022112066001332 ◽

1966 ◽

Vol 26 (3) ◽

pp. 459-479 ◽

Cited By ~ 36

Author(s):

H. Wong ◽

D. Bershader

Keyword(s):

Refractive Index ◽

Theoretical Analysis ◽

Thermal Equilibrium ◽

Mass Density ◽

Relaxation Times ◽

Ionization Mechanism ◽

Density Profiles ◽

Physical Mechanisms ◽

Thermal Equilibration ◽

Equilibrium Region

The physical mechanisms underlying the relaxation process leading to thermal equilibrium behind ionizing shock waves in argon have been studied through use of optical techniques. The non-equilibrium condition in the relaxation region was investigated experimentally by measuring the shift in the fringes due to a change in the refractive index of the medium with a Mach–Zehnder interferometer. Both electron- and mass-density profiles from the shock front to the equilibrium region were determined. The experimental work has been supplemented by a theoretical analysis of the ionization mechanism to explain the measured profiles and relaxation times.

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A fragmentation model of dust grains in the inner coma of Halley. A possible explanation of the color effect

International Astronomical Union Colloquium ◽

10.1017/s0252921100501900 ◽

1996 ◽

Vol 150 ◽

pp. 387-390

Author(s):

B. Goidet-Devel ◽

J. Clairemidi ◽

G. Moreels ◽

P. Rousselot

Keyword(s):

Refractive Index ◽

Mass Density ◽

Scattered Light ◽

Particle Radius ◽

Fragmentation Model ◽

Dust Grains ◽

Color Effect ◽

Dependent Mass ◽

Good Agreement

AbstractA model to describe the intensity of dust scattered light observed by the spectrometer TKS during the Vega/Halley encounter is presented. Good agreement is obtained when using a particle radius dependent mass density. The color effect is reproduced if the refractive index of tholin is adopted.

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