Polycarbonate reflection spectrum

On the other hand, the maximum absorption index of bands in the spectra of most organic molecules (including polymers) rarely exceeds 0.3 above 1000cm In these cases, ( 2 — 1) > and the reflection spectrum looks more like the n spectrum (see Figure Ab) than the k spectrum. The specular reflection spectrum of a polycarbonate polymer is shown in Figure 13.2. Few experienced spectroscopists would immediately recognize this spectrum as a polycarbonate. To convert this spectrum to the optical constant (n and k) spectra, the Kramers-Kronig... 

Figures 2 through 9 are design charts for ultraviolet stabilized polycarbonate under blast load. Charts are provided for pane thicknesses of 1/4, 3/8, 1/2, and 1 inch for pane areas up to 25 ft at pane aspect ratios (pane length to width ratios) of 1.00, 1.50, 2.00 and 4.00. The charts relate the peak experienced blast overpressure capacity, B, for convenient pane dimensions across the spectrum of encountered blast durations. Depending on the orientation of the window to the charge, the blast overpressure may either be incident or reflected. The pane dimensions (measured across the span from the gasket centerline) peak blast capacity at 1000 msec, B, static frame design pressure, r, and the required bite are printed to the right...

A further development of the use of MQ NMR to probe polymers is that of experimenter-imposed time-dependenee on R° ,(0, (f>), the coordinate space portion of S Cdii, via the use of MAS [33-35]. In these experiments, with the MQCOH being reflected in the intensity, (Iv(ti, t2))-, and subsequent 2D Fourier transform to yield I(wi, >2) as outlined in Section 6.1.2.2, the 2D spectrum of protons in polycarbonate was obtained. The development of spinning side-band patterns in this plot was demonstrated, as shown in Fig. 

Figure 29 Raman chemical imaging of the (NH4)2S04 particle on polycarbonate analyzed via SEM/EDS in Fig. 28A (A) bright-field reflectance image (B) polarized light-microscope image (C) Raman chemical image at the 965 cm" (NH4>2S04 band (D) dispersive Raman spectrum from the integrated region [dotted circle in (B)].

Representative results are shown in Figure 12.3, with ATR spectra of the same polymers being shown for comparison [8], although it should be noted that the ATR spectra were measured at higher resolution than the photothermal spectra. The distortion of the stronger bands in the ATR spectra of the more polar polymers is caused by the effect of anomalous dispersion when an internal reflection element (IRE) with a relatively low refractive index, presumably ZnSe, was used. Remarkably the highest quality of photothermal spectrum was measured in the case of polypropylene, which has a relatively weak spectrum, and the lowest quality spectrum was measured in the case of Nylon 6, where the effect of photoacoustic saturation [10] is clearly evident. It is interesting to speculate on whether this spectrum and that of polycarbonate would have been improved had the velocity of the interferometer mirror been increased. Spikes in some of the spectra at 1082 and 1804 cm were attributed to supply frequency harmonics. 

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