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Multiple attenuated internal

These investigations were aided substantially by use of the multiple attenuated internal reflection (MAIR) spectroscopic technique to record surface specific, infrared (IR) spectra in order to determine structure and monitor preparation and cleaning methods. [Pg.156]

Using contact angle measurements, Baier determined the critical surface tension of the spontaneously acquired films deposited on a clean inorganic solid placed in human mouths for periods of 30 sec, 2 min, and 15 min (14) see Table II). Concurrent determination of multiple attenuated internal refiection IR spectra of the adsorbed films provided evidence for the presence of protein material. While the spectra revealed... [Pg.293]

Only the methods used in this study (i, 2, 3) can detect and follow the initial events at the boundary between a solid substrate and the biological milieu. This extraordinary sensitivity derives from the ability to monitor events from within the substrate itself by making the substrate capable of supporting multiple attenuated internal reflection (MAIR) at a variety of useful spectroscopic wavelengths. In other studies, it was concluded that adsorbed protein on solid substrates is of essentially native i.e. solution or volume phase) conflguration and present in signiflcant thickness (6). Those studies used a different version of the internal reflection spectroscopic method wherein a prism element was forcefully... [Pg.305]

Fig. 4. Removal of an organic fatty acid monolayer on a water surface by a rising hydrophilic plate after the method of Blodgett (1934,1935) and its analysis by multiple attenuated internal reflection (Baier, 1970). Reproduced with permission of the author. Fig. 4. Removal of an organic fatty acid monolayer on a water surface by a rising hydrophilic plate after the method of Blodgett (1934,1935) and its analysis by multiple attenuated internal reflection (Baier, 1970). Reproduced with permission of the author.
Raman spectra of acidic aqueous solutions of M0C12-8H20 (M = Zr or Hf) have been examined in an effort to detect the zirconyl and hafnyl ions, M=0. No evidence for a v(M=0) Raman band in the region 800-1000 cm was found. A broad IR band centered at 1000 cm" is observed in the multiple attenuated internal reflectance spectrum of a concentrated ZrOCL solution. " However, this band shifts to lower frequency upon deuteriation, indicating that the solution species contains hydroxo bridges, and not zirconyl groups. Bands due to 6(ZrOH) in the 910-1030 cm region of the IR spectrum of crystalline... [Pg.2223]

Due to the fundamental importance of the adsorbed protein film, many methods have been used to characterize its nature. These methods include ellipsometry (3,A), Fourier transform infrared spectroscopy (FTIR) (5,6), multiple attenuated internal reflection spectroscopy (MAIR) (7,8) immunological labeling techniques (9), radioisotope labeled binding studies (j ), calorimetric adsorption studies (jj ), circular dichroism spectroscopy (CDS) (12), electrophoresis (j ), electron spectroscopy for chemical analysis (ESCA) (1 ), scanning electron microscopy (SEM) (15,16,9), and transmission electron microscopy (TEM) (17-19). [Pg.49]

Baier, R. E., and Zisman, W. A., Wettability and multiple attenuated internal reflection infrared spectroscopy of solvent-cast thin films of polyamides. Macromolecules, 3, 462-468 (1970). [Pg.933]

The second case refers to the so-called Internal Reflection Spectroscopy, that is used in the so-called Attenuated Multiple Total Internal Reflection technique... [Pg.103]

The main problem in IR measurements in situ is a strong IR absorption by the solvent water. Therefore the measurements in the classical transmission mode are practically excluded (the path length must not exceed 15 tan). Short path lengths are provided by the attenuated total reflection (ATR) mode. The probing light beam undergoes multiple total internal reflection in the ATR element (e.g. a cylindrical rod made of ZnSe, with two cone-sharpened ends) and each reflection... [Pg.348]

The formulation of a sulfur-vulcanized styrene-butadiene rubber (R2) mainly contains the rubber polymer and precipitated silica as filler the rest of the components are minor in amount, but they are important to impart adequate vulcanization and protect the rubber from the degradation under use (mainly paraffin wax). The paraffin wax acts as a physical protecting agent against ozone by migration to the rubber surface (Romero-Sanchez and Martin-Martinez 2004). O Figure 43.6 shows the attenuated multiple total internal reflection-infrared spectroscopy (ATR-FTIR) spectrum of the R2 bulk. The main bands correspond to rubber (styrene and butadiene) and silica, and the presence of CH2 moieties are minor corresponding to the paraffin wax. However, the ATR-FTIR spectrum of the R2 surface shows the main bands due... [Pg.1095]

Southern England. Changes produced by such a short exposure are not apparent from conventional multiple attenuated total internal reflectance i.r. studies but are readily detected by ESCA as will become apparent. [Pg.23]

Solid state spectra can be measured by the Attenuated Total Reflectance or Multiple Internal Reflection methods as well as by simple transmission techniques (222). Brooker (223) has reported the discovery of the translational vibrations of NaN02, NaNOs, and CaCOs (calcite). The orientation of the bonds in (U02)(N0s)2. 6 H2O has been ascertained from the spectra obtained in this manner (223). [Pg.104]

The most commonly used technique for obtaining a spectrum is the attenuated total reflectance (ATR) method in the multiple internal reflectance (MIR) mode. In this method, the infrared beam is passed into a special crystal of a selenide (KRS-5). The angle of incidence is such that the beam will bounce along the crystal. A sample of the polyurethane is placed hard up against the crystal. The infrared just penetrates into the material before it continues down the crystal. A number of internal bounces are obtained along the crystal. Up to 25 reflectances are obtained from a 2 mm crystal. Figure 9.8 illustrates the infrared path in an ATR cell. [Pg.190]

Diffuse Reflectance, Attenuated Total Reflection or Multiple Internal Reflection, Photoacoustic (PAS), Photothemal Beam Deflection, Specular Reflection Absorption, and forensic applications with the diamond cell and the Fourier transform infrared (FTIR) microscope. In museum laboratories, FTIR applications have been used for problems of identification and degradation in art and archeology. (14)... [Pg.240]

IR spectroscopy is a common analytical technique in the textile industry. IR is capable of identifying fibers and their additives, as well as showing quantitative blend ratios and additive contents. The ATR (attenuated total reflection) technique, especially in its multiple form, MIR (multiple internal reflection) is of special importance in this field. The sample preparation is simple and fast the cut out swatches with appropriate surface areas are placed against each side of the MIR crystal, ensuring sufficient and uniform contact across the crystal surface. The internal reflection methods are non-destructive, so that the sample may be saved for other types of analysis, they are, further, methods of surface analysis. This is advantageous in all cases where the finish resides primarily on the fiber surface. In this case, a very strong spectrum of the finish is obtained, with minimal interference from the base fiber (Hannah et al., 1975). [Pg.442]

The sample absorbs the evanescent field so that the totally reflected wave is attenuated accordingly the reflectance spectrum closely resembles a transmission spectrum. Usually such spectra can actually be inteipreted and evaluated as transmittance, and commercially available accessories are designed to support this. With angles of reflection well above the critical one, some sensitivity is lost which however is regained by multiple internal reflections. How pronounced the actual spectrum is, can be adjusted by the number of reflections used, i.e. the sample-coated area of the slab whether both surfaces, one surface, or just a fraction. In any case the area of a given reflection should fully be covered to avoid spectral dilution. [Pg.593]


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Attenuated multiple total internal reflection

Attenuated multiple total internal reflection technique

Attenuation intern

Internal reflection, multiple attenuated

MULTIPLE INTERNAL

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