Amorphous nonpolar aliphatic

Recent investigations have indicated that the aliphatic carbon fraction, rather than aromatic fraction, was strongly correlated to HOC sorption. For instance, the sorption of phenanthrene was related to nonpolar aliphatic carbon fraction, excluding poly(methylene), but was very strongly correlated with the content of the amorphous nonpolar aliphatic domains including amorphous poly(methylene) (Mao et al. 2002). In other words, the rubbeiy, relatively low-density, and amorphous nonpolar aliphatic carbon domains are excellent for phenanthrene partitioning (Figs. 3 and 4). 

Fig. 3. Correlation of the modified Freundlich coefficient K oc with the weight fraction of (a) nonpolar aliphatic carbon, excluding poly(methylene) and (b) amorphous nonpolar aliphatic carbon in domains, including amorphous poly(methylene). Adapted from Mao et al. (2002).

Mao J, Flundal L, Thompson M, Schmidt-Rohr K (2002) Correlation of poly(methylene)-rich amorphous aliphatic domains in humic substances with sorption of a nonpolar organic contaminant, phenanthrene. Environ Sci Technol 36 929-936... 

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