Reflection total

Total reflection occurs when the incident light is reflected without loss. This is especially important in the case of total internal reflection, since this principle is used in what is called fiber optics. 

With flexible bundles of light transmitters, light can, for example, be transmitted around corners, and one can even look around corners. Light transmitters are used in medicine to illuminate or observe internal organs, in industry for rear lights on autos, and for the postmarking of postage stamps on letters and parcels, etc. 

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ATR Attenuated total reflection Reflected beam attenuated Similar to IR... 

Figure Bl.22.4. Differential IR absorption spectra from a metal-oxide silicon field-effect transistor (MOSFET) as a fiinction of gate voltage (or inversion layer density, n, which is the parameter reported in the figure). Clear peaks are seen in these spectra for the 0-1, 0-2 and 0-3 inter-electric-field subband transitions that develop for charge carriers when confined to a narrow (<100 A) region near the oxide-semiconductor interface. The inset shows a schematic representation of the attenuated total reflection (ATR) arrangement used in these experiments. These data provide an example of the use of ATR IR spectroscopy for the probing of electronic states in semiconductor surfaces [44]-...

Attenuated total reflectance (ATR) cell for use In Infrared spectroscopy. 

Attenuated total reflectance spectroscopy and reflection-absorption infrared spectroscopy... 

The attenuated total reflectance (ATR) technique is used commonly in the near-infrared for obtaining absorption spectra of thin Aims and opaque materials. The sample, of refractive index i, is placed in direct contact with a material which is transparent in the region of interest, such as thallium bromide/thallium iodide (known as KRS-5), silver chloride or germanium, of relatively high refractive index so that Then, as Figure 3.f8... 

Figure 3.18 Total reflection of radiation in a medium of refractive index 2 by a thin film of refractive index wj, where 2...

Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy. Attenuated total redectance (atr) ftir spectroscopy is based on the principle of total internal redection (40). Methods based on internal redection in the uv and visible regions of the spectmm are also common in addition to those in the ir region. The implementation of internal redection in the ir region of the spectmm provides a means of obtaining ir spectra of surfaces or interfaces, thus providing moleculady-specific vibrational information. 

Attenuated total reflection, on which atr—ftir is based, occurs when the rarer medium is absorbing and is characterized by a complex refractive index (40). The absorbing characteristics of this medium allow coupling to the evanescent field such that this field is attenuated to an extent dependent on k. The critical angle in the case of attenuated total reflection loses its meaning, but internal reflection still occurs. Thus, if the internally reflected beam is monitored, its intensity will reflect the loss associated with the internal reflection process at the interface with an absorbing medium. 

Fig. 24. Attenuated total reflectance of thin film of thickness d and refractive index on a substrate of refractive index at the surface of internal reflection element (IRE) of refractive index Decay of evanescent field beyond thickness of thin film indicated.

Attenuated total reflection (ATR), also called internal reflection, is based on the phenomenon of total internal reflection. In ATR the infrared beam is directed into an infrared-transmitting crystal so that it strikes the crystal surface at less than the critical angle and undergoes total internal reflection. 

Total reflects the contribution of recovered platinum from the autocatalyst industry. ... 

Numbers in parentheses represent the quantity of palladium recovered from this industry. Total reflects the contribution of recovered palladium from the autocatalyst industry. ... 

Optical Properties. The index of refraction and extinction coefficient of vacuum-deposited aluminum films have been reported (8,9) as have the total reflectance at various wavelengths and emissivity at various temperatures (10). Emissivity increases significantly as the thickness of the oxide film on aluminum increases and can be 70—80% for oxide films of 100 nm. 

M. W. AT2rs1, Attenuated Total Reflectance Spectroscopy of Polymers Theory and Practice, American Chemical Society, Washington, D.C., 1996. 

For opaque materials, the reflectance p is the complement of the absorptance. The directional distribution of the reflected radiation depends on the material, its degree of roughness or grain size, and, if a metal, its state of oxidation. Polished surfaces of homogeneous materials reflect speciilarly. In contrast, the intensity of the radiation reflected from a perfectly diffuse, or Lambert, surface is independent of direction. The directional distribution of reflectance of many oxidized metals, refractoiy materials, and natural products approximates that of a perfectly diffuse reflector. A better model, adequate for many calculational purposes, is achieved by assuming that the total reflectance p is the sum of diffuse and specular components p i and p. ... 

DETERMINATION OF NUTRITIONAL PARAMETERS OF YOGHURT SAMPLES THROUGH PARTIAL-LEAST-SQUARES ATTENUATED TOTAL REFLECTANCE FOURIER TRANSFORM INFRARED SPECTROMETRY... 

The aim of this work is the determination of several nutritional parameters, such as Energetic Value, Protein, Fat, and Carbohydrates content, in commercially available yoghurt samples by using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FT-IR) spectrometry and a partial least square approach. 

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