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Absorbance integral

Figure C2.18.7. The integrated absorbance of tire Si-Cl stretching vibration at 625 cm and tire SiO-H stretching vibration at 3740 cm as a function of time during tire (A) SiCl and (B) H2O half-reactions at 600 K and 10 Torr. Reproduced from [95]. Figure C2.18.7. The integrated absorbance of tire Si-Cl stretching vibration at 625 cm and tire SiO-H stretching vibration at 3740 cm as a function of time during tire (A) SiCl and (B) H2O half-reactions at 600 K and 10 Torr. Reproduced from [95].
Early work by these authors established a relationship between Amono1/2, the square root of the integrated absorbance of the v16 ring bands in monosubstituted benzenes, and aR° for the substituents. The equation was usually written as follows126 ... [Pg.515]

For determination of the number of protonic sites and Lewis acid sites on the surface, the integrated absorbances of the bands at 1450 cm-i (due to pyridine chemisorbed on Lewis acid sites, L-Py) and 1490 cm i (due to both the L-Py and pyridine chemisorbed on protonic acid sites, B-Py) were used with the tangent background for all samples. The values obtained were normalized to the weight of the sample wafer. To obtain the apparent absorption coefficients of the bands, a known amount of pyridine was adsorbed on the sample, and the absorbance of each band was measured. Then, a small quantity of water which is sufficient to convert all Lewis acid sites into protonic acid sites was introduced into the IR-... [Pg.525]

The concentration of surface sites was measured by the integral intensity of the CO absorbance band using the formula C [pmol/g] = A/Aq, where A is the integral intensity of the CO stretching band and Aq is the coefficient of the integral absorbance [6]. Concentrations are measured to within 20%. [Pg.88]

KBr) databases. Quantitative analysis by GC-FUR is complicated by many uncertainties associated with both the chromatography and spectroscopy [196]. Bulk property detectors (e.g. TCD, FID, etc.) can be used for quantitative analysis when mixture components are known, but provide little structural information for unknown mixture components. Both integrated absorbance and Gram-Schmidt vector methods have been used for the quantitative analysis of mixture components in GC-FTIR. [Pg.458]

One cm3 of the reactant/product/catalyst mixture was sampled periodically during the reaction for the transmission infrared analysis (Nicolet Magna 550 Series II infrared spectrometer with a MCT detector). The concentrations of reactants and products were obtained by multiplying integrated absorbance of each species by its molar extinction coefficient. The molar extinction coefficient was determined from the slope of a calibration curve, a plot of the peak area versus the number of moles of the reagent in the IR cell. The reaction on each catalyst was repeated and the relative error for the carbamate yield measured by IR is within 5%. [Pg.476]

Fig. 6.16 The normalized integrated absorbance of SiH and SiH2 species (filled symbols), the PL intensity (open circles) and the specific surface area (open diamonds) as a... Fig. 6.16 The normalized integrated absorbance of SiH and SiH2 species (filled symbols), the PL intensity (open circles) and the specific surface area (open diamonds) as a...
Figure 8. Rate of starch disappearance from starch/P / AA plastic films incubated with a culture of starch-degrading bacteria (LD76). The proportion of starch remaining in the film was estimated from FTIR spectra as the integrated absorbance over the range 960-1190 cm". ... Figure 8. Rate of starch disappearance from starch/P / AA plastic films incubated with a culture of starch-degrading bacteria (LD76). The proportion of starch remaining in the film was estimated from FTIR spectra as the integrated absorbance over the range 960-1190 cm". ...
Table 4.1 Percentage of reconstructed integrated absorbance of each component compared to the total original experimental data. (E. Widjaja, C. Li, M. Garland, Organometallics, 2002, 27, 1991-1997.)... Table 4.1 Percentage of reconstructed integrated absorbance of each component compared to the total original experimental data. (E. Widjaja, C. Li, M. Garland, Organometallics, 2002, 27, 1991-1997.)...
Component Reconstructed integrated absorbance compared to the total original experimental data, %... [Pg.186]

The total acidity of different samples was measured by NHj-TPD with Micromeritics Autochem II (ASAP 2920) chemisorption system. The pyridine FT-IR spectra of the catalysts were recorded on a BIO-RAD FT3000 FT-IR spectrometer after desorption at 250 and 450°C, respectively. Then the total and strong acidity of Eewis and Bronsted acid was obtained from the integrated absorbance of the respective bands. [Pg.78]

The stabilized temperature platform furnace (STPF) concept was first devised by Slavin et al. It is a collection of recommendations to be followed to enable determinations to be as free from interferences as possible. These recommendations include (i) isothermal operation (ii) the use of a matrix modifier (iii) an integrated absorbance signal rather than peak height measurements (iv) a rapid heating rate during atomization (v) fast electronic circuits to follow the transient signal and (vi) the use of a powerful background correction system such as the Zeeman effect. Most or all of these recommendations are incorporated into virtually all analytical protocols nowadays and this, in conjunction with the transversely heated tubes, has decreased the interference effects observed considerably. [Pg.67]

The quantum yield of fluorescence from 3130-A excitation of gaseous acetone has been measured as 0.002,308 whereas a value of 0.01 has been measured in solution.316 If the rate of fluorescence, as calculated from the integrated absorbance intensity, is 4 x 10 sec-1,316 the rate of intersystem crossing of singlet acetone lies between 4 x 107 and 2 x 108 sec-1. [Pg.90]

Fig. 8. Effect of pyridine addition on integrated absorbance of 3650 cm 1 OH band of HY (41). (Reprinted with permission of the American Chemical Society.)... Fig. 8. Effect of pyridine addition on integrated absorbance of 3650 cm 1 OH band of HY (41). (Reprinted with permission of the American Chemical Society.)...
An extension of linear regression, MLR involves the use of more than one independent variable. Such a technique can be very effective if it is suspected that the information contained in a single independent variable (X) is insufficient to explain the variation in the dependent variable (Y). For example, it is suspected that a single integrated absorbance of the NIR water band at 1920 nm is insufficient to provide accurate concentrations of water contents in process samples. Such a situation can occur for several reasons, such as the presence of other varying chemical components in the sample that interfere with the 1920-nm band. In such cases, it is necessary to use more than one band in the spectrum to build an effective calibration model, so that the effects of such interferences can be compensated. [Pg.236]

Fig. 8 Integrated absorbance of the C = O stretching band (1760-1680 cm-1) in micropore regions compared to bulk regions of the PMMA membrane. The evaluation is based on the centroid spectra of the spectral clusters in the pore center and across the bulk region... Fig. 8 Integrated absorbance of the C = O stretching band (1760-1680 cm-1) in micropore regions compared to bulk regions of the PMMA membrane. The evaluation is based on the centroid spectra of the spectral clusters in the pore center and across the bulk region...
Fig. 2 i FTIR spectra of 0.1 xm silica particles in radius (a) bare (b) with chemisorbed GPS (c) with grafted PS ii Calibration plot for PS grafted layer in the mixture of PS powder with silica particles o 0.1 xm and A 1.2 urn in radius in terms of the FTIR spectrum integral absorbance vs. mass fraction of the polymer... [Pg.76]

Figure 4.8 shows an example for this mode of correction applied for the determination of Pb in pig kidney reference material, using direct solid sample analysis. The three-dimensional plot in Figure 4.8a shows that a strong molecular absorption with pronounced fine structure appears short after the atomic absorption signal. Figure 4.8b shows the time-integrated absorbance spectrum of PO,... [Pg.92]


See other pages where Absorbance integral is mentioned: [Pg.2938]    [Pg.195]    [Pg.101]    [Pg.515]    [Pg.499]    [Pg.149]    [Pg.299]    [Pg.112]    [Pg.124]    [Pg.325]    [Pg.458]    [Pg.506]    [Pg.147]    [Pg.25]    [Pg.186]    [Pg.137]    [Pg.137]    [Pg.21]    [Pg.213]    [Pg.268]    [Pg.102]    [Pg.212]    [Pg.71]    [Pg.212]    [Pg.212]    [Pg.225]    [Pg.225]    [Pg.226]    [Pg.226]    [Pg.227]    [Pg.231]    [Pg.233]    [Pg.233]   


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Absorbance integrated

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