my.chemeurope.com
With an accout for my.chemeurope.com you can always see everything at a glance – and you can configure your own website and individual newsletter.
RATIONALE
Stable isotopes of nitrogen in nitrate (NO3–) are frequently used to identify nitrate sources and to study nitrogen (N) transformation processes, but the measurement methods available are generally rather labor intensive and/or costly, and dissolved organic matter (DOM) can interfere with the δ15N signature of nitrate. We therefore have developed a simple cleanup procedure for freshwater samples with low nitrate and high DOM concentrations.
METHODSNitrate and DOM are extracted from a freeze‐dried water sample by using a concentrated sodium hydroxide solution. By the subsequent addition of acetone, two liquid layers are formed, and nitrate migrates into the acetone while DOM remains in the concentrated NaOH solution, thus separating the nitrate from the DOM. For nitrogen isotope analysis, purified nitrate salts are combusted at 1030 °C to produce N2 gas in an elemental analyzer (EA) coupled to an isotope ratio mass spectrometer (IRMS).
RESULTSWith this novel technique up to 99% of DOM could be removed from river water and soil solutions. The method has been tested for sample amounts as small as 4 µmol NO3– with a precision of <0.1‰ (1SD). Nitrate standards are reproduced accurately without any blank correction.
CONCLUSIONSThe benefits of this method are the lack of interferences derived from DOM on the δ15N signature and the ease of sample preparation. Copyright © 2012 John Wiley & Sons, Ltd.
| Authors: | Huber, Benjamin; Bernasconi, Stefano M.; Pannatier, Elisabeth Graf; Luster, Jörg | |
| Journal: | Rapid Communications in Mass Spectrometry | |
| Volume: | 26 | |
| Issue: | 12 | |
| Year: | 2012 | |
| Pages: | 1475 | |
| DOI: | 10.1002/rcm.6243 | |
| Publication date: | 30-06-2012 |
Watchlist
This is where you can add this publication to your personal favourites.
Additional Information
Vesicle‐Mediated Growth of Tubular Branches and Centimeter‐Long Microtubes from a Single Molecule
Abstract The mechanism by which small molecules assemble into microscale tubular structures in aqueous solution remains poorly understood, particularly when the initial building blocks are non‐amphiphilic molecules and no surfactant is used. It is here shown how a subnanometric molecule ... more
The image illustrates a natural phenomenon of droplet formation caused by the condensation of vapor on a nonwettable surface at temperature below the dew point. Real‐time observing the light scattered from the droplets may lead to a new mechanism for vapor sensing. However, the dew point ... more
NO is a key vasodilator in mammalian cardiovascular systems and has been shown to sensitize tissue to γ‐radiation. However, photochemical NO precursors that can be activated by these NIR wavelengths are extremely limited. G. D. Stucky, D. Zhao, P. C. Ford, F. Zhang and co‐workers have ad ... more
Bioengineers Succeed in Producing Plastic Without the use of Fossil Fuels
A team of pioneering South Korean scientists have succeeded in producing the polymers used for everyday plastics through bioengineering, rather than through the use of fossil fuel based chemicals. This groundbreaking research, which may now allow for the production of environmentally consci ... more
In the past, restoration of paintings and other old artwork often involved application of acrylic resins to consolidate and protect them. One of the most important tasks for modern restorers is thus to remove these layers, because it turns out that acrylic resins not only drastically change ... more
Is trash the solution to tackling climate change?
Converting the trash that fills the world's landfills into biofuel may be the answer to both the growing energy crisis and to tackling carbon emissions, claim scientists in Singapore and Switzerland. New research published in Global Change Biology: Bioenergy, reveals how replacing gasoline ... more
Über CHEMIE.DE
CHEMIE.DE Information Service GmbH runs specialist scientific internet portals. The secret to our success? We are familiar with what we publish.
Advertising at CHEMIE.DE
Our advertising formats support you in getting your message across to a clearly defined target audience.
© 1997-2013 CHEMIE.DE Information Service GmbH, All rights reserved
Netmeeting
