| Abstract: | The number- and weight-averaged molecular weights of a number of aquatic fulvic acids, a commercial humic acid, and unfractionated organic matter from four natural water samples were measured by high-pressure size exclusion chromatography (HPSEC). Molecular weights determined in this manner compared favorably with those values reported in the literature. Both recent literature values and our data indicate that these substances are smaller and less polydisperse than previously believed. Moreover, the molecular weights of the organic matter from three of the four natural water samples compared favorably to the fulvic acid samples extracted from similar environments. Bulk spectroscopic properties of the fulvic substances such as molar absorptivity at 280 nm and the E4/E6 ratio were also measured. A strong correlation was observed between molar absorptivity, total aromaticity, and the weight average molecular weights of all the humic substances. This observation suggests that bulk spectroscopic properties can be used to quickly estimate the size of humic substances and their aromatic contents. Both parameters are important with respect to understanding humic substance mobility and their propensity to react with both organic and inorganic pollutants. ?? 1994 American Chemical Society. |
| Genre: | Article |
| ProdID: | 70016741 |
| Citation Author: | Chin, Y. -P.; Aiken, G.; O'Loughlin, E. |
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| Citation End Page: | 1858 |
| Citation Issue: | 11 |
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| Citation Language: | English |
| Citation Larger Work Title: | Environmental Science and Technology |
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| Citation Number Of Pages: | 6 |
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| Citation Search Results Text: | Molecular weight, polydispersity, and spectroscopic properties of aquatic humic substances; 1994; Article; Journal; Environmental Science and Technology; Chin, Y. -P.; Aiken, G.; O‘Loughlin, E. |
| Citation Start Page: | 1853 |
| Citation Volume: | 28 |
| Citation Year: | 1994 |
| Type: | citation/reference |
| Text: | Molecular weight, polydispersity, and spectroscopic properties of aquatic humic substances; 1994; Article; Journal; Environmental Science and Technology; Chin, Y. -P.; Aiken, G.; O‘Loughlin, E. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Sat, 1 Jan 1994 00:00 -0600 |
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