Carbonyl emission

The x-ray photoelectron spectra for both dissolved and solventless polyamic acid have been reported in the literature [2-8], It has been noted previously by us [5-7], that the spectra for solventless PAA and PI exhibit a pronounced deficiency for the Cls and Ols carbonyl emission. This, together with an analysis of the Nls lineshape and the Ols and Cls shake up features, allows us to derive conclusions on the chemical nature of solventless polyamic acid and to explain it s high reactivity towards metals as discussed below. 

Figure 5 Plot of the integrated Ols "shake-up" intensity (left y-axis) from fig. 2 and energy in eV (right y-axis) relative to the Ols carbonyl emission at various curing temperatures. Error bars are estimated.

Another interesting result is given by NMR measurement that the carbonyl emission in the ester linkage was split in two peaks in both of the B2 and B4 phases. Of course, the isotropic phase shows oidy rme peak [140]. The presence of two... 

Pang, X.B., Mu, Y.J., Yuan, J., He, H., 2008. Carbonyls emission from ethanol-blended gasoline and biodiesel-ethanol-diesel used in engines. Atmospheric Environment 42, 1349-1358. 

Carbon monoxide was discovered in 1776 by heating a mixture of charcoal and 2inc oxide. It provided a source of heat to industry and homes as a component of town gas and was used as a primary raw material in German synthetic fuel manufacture during World War II its compounds with transition metals have been studied extensively (see Carbonyls). Most recently, carbon monoxide emission from vehicle exhausts has been recognized as a primary source of air pollution (qv). 

Significant stimulated emission is only found for the pristine side of the sample. From these results it was concluded that the photoinduccd absorption that suppresses die stimulated emission is directly or indirectly caused by the presence of oxygen-related defects. It was shown earlier that the effect of photooxidation on the emission properties of PPV can be explained by the formation of carbonyl-groups that act as sLrong electron acceptors leading to an efficient dissociation of the plioh excited slate 29). It can be concluded that the dissociated pair near the defcci leads to the strong photoinduccd absorption. The observation that... 

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