Normalized spectra

Figure 5 Normalized spectra from test object "Lower wing skin".

All P.M.R. spectra were measured with a Varian HA 100 spectrometer operating in the frequency-sweep mode with tetramethylsilane as the reference for the internal lock. The double and triple resonance experiments were performed using a Hewlett Packard 200 CD audio-oscillator and a modified Hewlett Packard 200 AB audio-oscillator (vide infra). Spectra were measured using whichever sweep width was required to ensure adequate resolution of the multiplets under investigation, generally 250 or 100 Hz, and sweep rates were selected as necessary. Extensive use was made of the Difference 1 and Difference 2 calibration modes of the instrument, both for the decoupling experiments and for the calibration of normal spectra. 

Software designed to normalize spectra to database standards. (Step 7)... 

Fig. 13.9 Frequency dependence of potassium atom emission from argon-saturated 2 M KC1 aqueous solutions. Shown are normalized spectra measured at frequencies of 28, 115,...

Once we have acquired the data, we have two time domains (one from the normal acquisition time, the other from the incremented delay, hence the data is now 2-D ). As with normal spectra, we need to look at the data in the frequency domain. We do this by Fourier transformation, first in one dimension and then in the other. The resultant data can be portrayed or plotted in one of two different formats. 

Figure 9. Normalized spectra of the base form of four indicators (1 - phenol red, 2 - bromo-cresol purple, 3 - thymol blue, and 4 -bromocresol green).

Data reduction of EXAFS spectra was performed using WinXAS [14], The normalized spectra were analyzed over the Arrange of 2.5 to 10 A1. A square-weighted degree 7 spline was used to remove the background of the x(k) function. Finally, the data in -space were converted to R-space using a Bessel window to obtain the radial distribution function. 

Fig. 19.10 (a) Normalized spectra of FRET in free space forR6G (donor) andLDS722 (acceptor). The bottom curve (A/D 1.0/0 mM) is acquired in the absence of the donor. The donor concentration for the remaining curves is fixed at 0.1 mM. The CW pump wavelength 532 nm. A/D acceptor to donor ratio, (b) Energy transfer efficiency, e, calculated from (a). Solid line is the theoretical curve for the efficiency with a parameter c0 1.7 mM, corresponding to R0 6.2 nm. Reprinted from Ref. 18 with permission. 2008 Optical Society of America... 

The first PLS factor represents the manner in which the spectra change with respect to the analytical values attached. That is (for normal spectra, not derivatives) as the correlation between change in absorbance and constituent value is greatest, there is a large peak or... 

Metalloporphyrins containing low valent main group elements show hyper-type UV-visible spectra and the corresponding higher valent complexes show normal spectra. Despite this, the phosphorus complexes [P(OEP)R2] show spectra with distinctly hyper character, with two extra Soret bands apparent. The extra Soret band in hyper complexes has been assigned to charge transfer from the low... 

FIGURE 2. Normalized spectra of the CIEEL emission in the fluotide-ion-triggered ([n-BiLtNE] = 6.3 X 10 M) decomposition of the dioxetanes (10 M) m-15a and m-15b at ca 20°C in MeCN and of the fluorescence emission (Xex = 330 nm) for the corresponding methyl m-oxyhenzoate ions (10 M) m-17a and m-17b under the same conditions. Reprinted with permission from Reference 34a. Copyright (1998) American Chemical Society... 

The theory of the Fe(III) heme spectra has been given in the previous article (52) and in particular the difference between the absorption spectra of high-spin and low-spin species has been stressed. The application of this theory to some proteins has also been described in that article but its purpose was mainly to draw attention to normal spectra. Here we shall point to a number of anomalous spectra especially concerning the movement of the Soret band to much shorter wavelengths than 400 nm. There is a simultaneous notable broadening of this band and a fall in its extinction coefficient. Such effects have frequently been seen in simple model systems and so we deal these first. 

Figure 5. Normalized spectra of Foron Brilliant Blue S-R and analogs.

Figure 7. Normalized spectra of barbituric acid dyes.

Figure 8. Normalized spectra of extended barbituric acid chromophores.

Figure 2.1 shows representative second-derivative normalized spectra from the sample compared with pure component spectra of acetaminophen, aspirin and caffeine. The single-pixel spectra are from 9.7 x 9.7 jxm areas on the surface of the tablet, each with signal to noise greater than 5000 1, which is comparable to a standard NIR spectrometer. This comparison between pure component spectra and single-pixel spectra ensures that the assignment of the component pixel spectra from the tablet is accurate. The spectra of these three components show spectral... 

Figure 10.7 (a) H E section from a section of tissue with anatomical features consistent with villog-landular adenocarcinoma, (b) UHCA map of five clusters calculated over the 1800-950 cm-1 region on second-derivative vector normalized spectra, (c) Mean extracted spectra from the raw data representing each cluster, (d) Stack plot showing cluster maps performed on five adjacent sections from the same tissue. 

The wavenumber resolution was set at 6 cm-1 and 16 scans were coadded for each spectrum. UHCA was performed on the 1800-950 cm-1 region on second-derivative vector normalized spectra. The brown cluster and resultant mean extracted brown spectrum in Fig. 10.7(c) are representative of the dispersion artifact from... 

Figure 15.8 Examples of spectral integration and normalization. Spectra shown were obtained with nitroxide label 14 (Fig. 15.3C). Acquisition parameters are listed in Table 15.1, except that number of scans = 4 and number of points = 1024. (A) Spectrum of an aqueous sample of a 23-nt RNA, together with its 1st and 2nd integrals. (B) Spectral comparison between a 23-nt RNA (40 gM, dotted line) and a 49-nt RNA (30 jiM, sobd Une). Comparison of the normalized spectra is not skewed by the different amount of labeled RNAs used in the measurement, and reports different nitroxide behavior due primarily to the difference in RNA size. (C) An example of spin counting. The calibration curve was generated by linear fitting (solid Une) of data points (sobd square) obtained using tempol solutions of various concentrations. Using this calibration curve, the sample measured in (A) was found to contain 37.5 gM of spins ( sample = 2.5). Based on an RNA concentration of 40 jiM, the nitroxide labeling efficiency was determined to be 93.6%.

The fraction of protein, eluted from Sephadex G-75 which behaves as a single homogeneous protein with respect to its interactions with M2 was also studied with regard to its interaction with monosaccharides. The association constant of the interaction of M2 with intact con A is 19 times greater than that obtained for the interaction of p-nitrophenyl a-D-mannopyranoside with con A. The normalized spectra (Figure 7) of the monosaccharide and disaccharide complexes were found to be very similar suggesting that the interactions between con A and the nitrophenyl group which causes the spectral perturbation are the same for both complexes. 

FIGURE 4.7 Illustration of normalization applied to Raman spectra, (a) Original spectra, (b) Normalized spectra. 

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