dc.contributor.author |
Khlystov, Andrey |
|
dc.contributor.author |
Ma, Yilin |
|
dc.date.accessioned |
2013-04-01T14:37:49Z |
|
dc.date.issued |
2006 |
|
dc.identifier.issn |
1352-2310 |
|
dc.identifier.uri |
https://hdl.handle.net/10161/6452 |
|
dc.description.abstract |
The Steam-Jet Aerosol Collector-long Pathlength Absorbance Spectroscopy (SJAC-LPAS),
an on-line continuous instrument for mobile measurements of spatial distribution of
water-soluble hexavalent and trivalent chromium in ambient aerosols, has been developed
and is presented here. The system collects particles with the SJAC and analyzes the
collected sample on-line using the diphenycarbazide (DPC) colorimetric method. By
using a Teflon AF (Amorphous Fluoropolymer) liquid core wave guide, the limit of detection
has been significantly improved, allowing on-line measurements at ambient concentrations.
The limit of detection for Cr(VI) is 0.2 ng m(-3). Water-soluble Cr(III) can also
be measured by oxidizing it to Cr(VI) in a parallel line using hydrogen peroxide before
the detection with the DPC method. The concentration of Cr(III) is then determined
as the difference between the two lines (Cr(VI) and Cr(VI) plus Cr(III)). The instrument
was specifically designed to be used on a mobile platform to study spatial distribution
of the pollutant within a city on a scale of 100 m. Special attention was given to
the time resolution and the stability of the instrument performance under driving
conditions. The time resolution of the instrument is 15 s. At a typical driving speed
of 30 km h(-1) the instrument can detect variations in chromium concentration ({''}hot
spots{''}) on the scale of about 150 m. The instrument has proven to operate reliably
and capture temporal and spatial variability of Cr(VI) concentration during four mobile
measurement campaigns in Wilmington, DE. (c) 2006 Elsevier Ltd. All rights reserved.
|
|
dc.publisher |
Elsevier BV |
|
dc.relation.ispartof |
ATMOSPHERIC ENVIRONMENT |
|
dc.title |
An on-line instrument for mobile measurements of the spatial variability of hexavalent
and trivalent chromium in urban air
|
|
dc.type |
Journal article |
|
duke.contributor.id |
Khlystov, Andrey|0312531 |
|
pubs.begin-page |
8088 |
|
pubs.end-page |
8093 |
|
pubs.issue |
40 |
|
pubs.organisational-group |
Duke |
|
pubs.organisational-group |
Faculty |
|
pubs.publication-status |
Published |
|
pubs.volume |
40 |
|