HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by Hettiarachchi, G. M. Articles by Newville, M. Search for Related Content PubMed PubMed Citation Articles by Hettiarachchi, G. M. Articles by Newville, M. Agricola Articles by Hettiarachchi, G. M. Articles by Newville, M. Related Collections Municipal Waste Toxic Trace Metals Sorption/Exchange Heavy Metals Soil Surface Chemistry

µ-XANES and µ-XRF Investigations of Metal Binding Mechanisms in Biosolids

^a Dep. of Soil and Water, School of Earth and Environmental Science, Univ. of Adelaide, Glen Osmond, SA 5064, Australia
^b National Risk Management Res. Lab., USEPA, 5995 Center Hill Ave., Cincinnati, OH 45224
^c GSECARS, Univ. of Chicago, Chicago, IL 60637

View larger version (112K): [in a new window]   Fig. 1. X-ray fluorescence maps of selected metals in the intact LC biosolids sample. Area of a single map is 400 by 400 µm. The color scheme employed ranges from white–yellow for high fluorescence signal to blue–black for low fluorescence signal. Shading is relative across the single map. The eight markers noted as 1 to 8 represent locations for which µ-XANES analyses were conducted. The XANES spectra are presented in Fig. 6 and 7, and the XANES fitting is presented in Table 2.

View larger version (13K): [in a new window]   Fig. 2. The correlation between the fluorescence signals of Fe collected at 14 000 eV and Mn at 7102 eV in (a) the intact and (b) OC removed LC biosolids sample. Each point on the graph represents a pixel in Fig. 1.

View larger version (26K): [in a new window]   Fig. 3. Correlations between the fluorescence signals of Fe and Cu, Zn, Pb, and Cr in the intact LC biosolids sample. The fluorescence signals of Fe, Cu, Zn, and Pb were collected at 14 000 eV and Cr was collected at 7102 eV. Each point on the graph represents a pixel in Fig. 1.

View larger version (68K): [in a new window]   Fig. 4. (a) Optical image of 220 by 120 µm area for the intact Nu-Earth biosolids sample, (b) X-ray fluorescence map of Fe, (c) X-ray fluorescence map of Cd, and (d) correlation between Fe and Cd fluorescence signals.

View larger version (19K): [in a new window]   Fig. 5. Correlations between fluorescence signals of Fe and Cu, Zn, Pb, and Cr in the OC-removed LC biosolids sample.

View larger version (26K): [in a new window]   Fig. 6. The XANES spectra of selected Fe-containing standard minerals and several different Fe hotspots in the LC biosolids sample. Dotted lines indicate the linear combination XANES fits using all the standard compounds that are listed in Table 2. Vertical lines represent white line peaks for Fe2+ and Fe3+, respectively.

View larger version (29K): [in a new window]   Fig. 7. The first derivative of the XANES spectra of selected Fe-containing standard minerals and several different Fe hotspots in the LC biosolids sample. The numbers correspond with locations shown on Fig. 1. Vertical dotted lines represent white line peaks for Fe2+ and Fe3+, respectively.