Results 221 to 230 of about 19,017 (243)

Evaluation of emulsion stability by diffuse reflectance spectroscopy

Journal of Pharmaceutical Sciences, 1976
A new method is described for evaluating the stability of emulsion bases and active components contained within such emulsions. Diffuse reflectance spectroscopy (DRS) is a technique that has the capability of detecting changes in particle size, surface properties, or drug quality of emulsions as a function of time without disturbance of the system ...
M J, Akers, J L, Lach
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Diffuse reflectance spectroscopy—Important developments

Mikrochimica Acta, 1988
Effect of front surface reflectance is incorporated into standard Kubelka-Munk theory of diffuse reflection. A method of obtaining the absorption coefficient independent of scattering coefficient is presented.
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Autofluorescence and diffuse reflectance spectroscopy for oral oncology

Lasers in Surgery and Medicine, 2005
AbstractBackground and ObjectivesAutofluorescence and diffuse reflectance spectroscopy have been used separately and combined for tissue diagnostics. Previously, we assessed the value of autofluorescence spectroscopy for the classification of oral (pre‐)malignancies.
de Veld, Diana C. G., Skurichina, Marina, Witjes, Max J. H., Duin, Robert P. W., Sterenborg, Henricus J. C. M., Roodenburg, Jan L. N.   +5 more
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Diffuse reflecting material for integrating cavity spectroscopy, including ring-down spectroscopy

Applied Optics, 2015
We report the development of a diffuse reflecting material with measured reflectivity values as high as 0.99919 at 532 nm and 0.99686 at 266 nm. This material is a high-purity fumed silica, or quartz powder, with particle sizes on the order of 40 nm.
Michael T, Cone, Joseph A, Musser, Eleonora, Figueroa, John D, Mason, Edward S, Fry   +4 more
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Fourier Analysis Enhances NIR Diffuse Reflectance Spectroscopy

Applied Spectroscopy, 1984
Fourier coefficients computed from the NIR spectra of pulverized tobacco samples can be used to estimate certain chemical constituents in the samples. As few as 11 coefficients from the Fourier domain used in a stepwise multiple linear regression (SMLR) model provide results equivalent to a 7-term SMLR model using log 1/ R from the wavelength domain ...
W. F. McClure, Abdul Hamid, F. G. Giesbrecht, W. W. Weeks   +3 more
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Principles and Techniques of Diffuse‐Reflectance Spectroscopy

Angewandte Chemie International Edition in English, 1963
AbstractThe prerequisites for applicability of the Kubelka‐Munk theory of diffuse reflectance for obtaining characteristic color curves of powders are discussed, and some experimental support for the theory is given. Methods are described for eliminating surface reflection, which is always superimposed upon the diffuse reflection and which therefore ...
G. Kortüm, W. Braun, G. Herzog
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Near-Infrared Diffuse Reflectance Spectroscopy of Coal

Applied Spectroscopy, 1985
Near-infrared (NIR) diffuse reflectance has become an accepted method for quantitative analysis of a variety of organic solids. The technique, associated instrumentation, and applications have been comprehensively reviewed by Wetzel. NIR reflectance analysis usually utilizes mathematical correlation techniques to extract compositional and property data
Stuart A. Fysh, Dom A. J. Swinkels, Peter M. Fredericks   +2 more
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Diffuse reflectance spectroscopy: a comparison of the theories

Applied Optics, 1975
The various theories of diffuse reflectance spectroscopy are compared mathematically, and it is concluded that the modified particle model theory is probably the most nearly correct. If so, the comparison shows that the simple, easily applied simplified particle model theory is approximately valid for relative index of refraction values of 1.5-2.5 and ...
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Diffuse Reflectance Spectroscopy

C R C Critical Reviews in Analytical Chemistry, 1971
Roland W. Frei, Harry Zeitlin
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Optimization of Diffuse Reflectance Infrared Spectroscopy Accessories

Applied Spectroscopy, 1986
The value of diffuse reflectance as an infrared or near-infrared spectroscopic sampling procedure has been limited by the low efficiency of accessories designed for it. In terms of signal-to-noise ratio, these average 2–6% for integrating spheres and 10–12% for various ellipsoidal mirror arrangements.
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