FTIR concentration integrals

Fig. 39 The mean concentration integrals I recorded by FTIR (diamonds) and interference microscopy (points) along the y direction for x values between 35 and 55 xm x, y, and z are the crystallographic directions...

New reagentless, E-Field based samphng approaches have been developed and integrated with conventional ATR-FTIR flow cells for the detection and identification of bacterial spores in water. Our results show how E-field concentration of spores onto the surface of an ATR crystal surface can enable low concentrations of spores to be measured. The collection cells are designed for easy interface with virtually any IR spectrometer or detection system, and can prove usefirl in a variety of military, homeland defense, and technological apphcations. 

Quantitative measurements in FTIR spectroscopy are based on the empirical Beer-Lambert-Bouguer law interrelating the intensity of light absorption and the concentration of a substance being analyzed. For FTIR spectroscopy of adsorbed molecules, this law is applied in the integral form ... 

Figure 7.2 Transmission FTIR images of PA, silicone oil, and PTFE in the pol)rmer blend. Image size is 266 x 266 pm. (a) Visible image of the polymer blend. FTIR images created by integrating, (b) the polyamide band between 1677 and 1597 cm", (c) the silicone oil band between 1290 and 1240 cm , and (d) the PTFE band between 1174 and 1122 cm . Red regions represent a high concentration, while blue regions represent a low concentration. (See eBooks for color version of this figure).

To obtain the data needed to plot a calibration line the absorbances of a series of standard samples are measured either as a peak height at a specific wavenumber, or as an integrated peak area. The concentrations of the standards must be obtained by some method other than FTIR. Frequently, standards are made with measured... 

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