Volume Changes in Petroleum Waxes as Determined from Refractive Index Measurements.

1958 ◽  
Vol 3 (2) ◽  
pp. 352-359 ◽  
Author(s):  
D. Harrison ◽  
A. Reingold ◽  
W. Turner
Keyword(s):  
Refractive Index ◽  
Volume Changes

scholarly journals PHOTOMETRIC EVIDENCE FOR THE OSMOTIC BEHAVIOR OF RAT LIVER MICROSOMES

1963 ◽  
Vol 18 (3) ◽  
pp. 503-513 ◽  
Author(s):  
Henry Tedeschi ◽  
Joseph M. James ◽  
William Anthony
Keyword(s):  
Refractive Index ◽  
Electron Microscope ◽  
Incident Light ◽  
Liver Microsomes ◽  
Photometric Data ◽  
Rat Liver Microsomes ◽  
Volume Changes ◽  
Osmotic Behavior ◽  
Electron Microscope Data

Electron microscope observations are consistent with the interpretation that the elements of the endoplasmic reticulum are osmotically active in situ as well as after isolation. More recently, it has been reported that microsomal suspensions equilibrate almost completely with added C14-sucrose and that no osmotic behavior is evident from photometric data. These findings were considered at variance with the electron microscope data. However, equilibration with added label simply attests to a relatively high permeability, and, in addition, the photometric data need not be critical. Osmotic volume changes, measured photometrically, may be masked by concomitant events (e.g., changes in the refractive index of the test solutions at varying osmotic pressures, breakdown of the particles, and agglutination). For these reasons the photometric experiments were repeated. In this work, the reciprocal of optical density of microsomal suspensions was found to vary linearly with the reciprocal of concentration of the medium at constant refractive index. These changes probably correspond to osmotic volume changes, since the effect was found to be (a) independent of substance used and (b) osmotically reversible. The transmission of the suspension was found to vary with the refractive index of the medium, the concentration of particles, and the wavelength of incident light, according to relationships that are similar to or identical with those obtained for mitochondrial suspensions.

scholarly journals Quantitative phase imaging of erythrocytes under microfluidic constriction in a high refractive index medium reveals water content changes

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Han Sang Park ◽  
Will J. Eldridge ◽  
Wen-Hsuan Yang ◽  
Michael Crose ◽  
Silvia Ceballos ◽  
...  
Keyword(s):  
Refractive Index ◽  
Red Blood Cells ◽  
Mechanical Stress ◽  
Blood Cells ◽  
High Refractive Index ◽  
Phase Imaging ◽  
Quantitative Phase Imaging ◽  
Water Displacement ◽  
Volume Changes ◽  
Quantitative Phase

AbstractChanges in the deformability of red blood cells can reveal a range of pathologies. For example, cells which have been stored for transfusion are known to exhibit progressively impaired deformability. Thus, this aspect of red blood cells has been characterized previously using a range of techniques. In this paper, we show a novel approach for examining the biophysical response of the cells with quantitative phase imaging. Specifically, optical volume changes are observed as the cells transit restrictive channels of a microfluidic chip in a high refractive index medium. The optical volume changes indicate an increase of cell’s internal density, ostensibly due to water displacement. Here, we characterize these changes over time for red blood cells from two subjects. By storage day 29, a significant decrease in the magnitude of optical volume change in response to mechanical stress was witnessed. The exchange of water with the environment due to mechanical stress is seen to modulate with storage time, suggesting a potential means for studying cell storage.

The permeation of water into chick heart fibroblasts in tissue culture

1959 ◽  
Vol 150 (938) ◽  
pp. 43-52 ◽  
Keyword(s):  
Tissue Culture ◽  
Refractive Index ◽  
Diffusion Coefficient ◽  
Cell Membrane ◽  
Permeability Coefficient ◽  
The Other ◽  
Volume Changes ◽  
Fluid Medium ◽  
Chick Heart ◽  
Time Required

By employing the technique of immersion refractometry to measure volume changes, a study has been made of the rate of entry of water into chick heart fibroblasts cultured in a fluid medium. The time required for the cytoplasm of the fibroblast to reach a given refractive index, when the cell is exposed to a low external osmotic pressure, is a measure of its permeability. It is pointed out that all calculations applied to such data depend on various more or less arbitrary assumptions. A number of calculations made on different assumptions give estimates of the permeability coefficient for the cell membrane varying from 1.41 to 2.82 μ min -1 atm -1 at 38°C, or on the other hand, estimates of the diffusion coefficient of water in the protoplasm varying from 1.7 x 10 -10 to 6.6 x 10 -10 cm 2 /s.

TEM characterization of proton-exchanged LiNbO3 optical waveguides

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.

Light microscopy of ceramics

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).

On the refractive index of rutile

1992 ◽  
Vol 139 (2) ◽  
pp. 163 ◽  
Author(s):  
M.R. Shenoy ◽  
R.M. de la Rue
Keyword(s):  
Refractive Index
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