Results 211 to 220 of about 18,269 (245)

A novel tool for stable nitrogen isotope analysis in aqueous samples

Rapid Communications in Mass Spectrometry, 2016
Rationale Bulk stable isotope analysis (BSIA) of dissolved matter (e.g. dissolved organic carbon, total nitrogen bound (TN b ), etc.) is of particular importance since this pool is a prime conduit in the cycling of N and C.
E. Federherr, H. J. Kupka, C. Cerli, K. Kalbitz, R. Dunsbach, A. Loos, M. de Reus, L. Lange, R. J. Panetta, T. C. Schmidt   +9 more
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Stable carbon and nitrogen isotope analysis of avian uric acid

Rapid Communications in Mass Spectrometry, 2008
Abstract We report results obtained using a new technique developed to measure the stable‐isotope composition of uric acid isolated from bird excreta (guano). Results from a diet‐switch feeding trial using zebra finches suggest that the δ 13 C of uric ...
Bird, Michael I., Tait, Elaine, Wurster, Christopher M., Furness, Robert W.   +3 more
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USING STABLE ISOTOPES TO MONITOR ANTHROPOGENIC NITROGEN INPUTS TO ESTUARIES

Ecological Applications, 2008
Use of stable nitrogen isotope ratios is one method that has been proposed to indicate anthropogenic nutrient enrichment in estuarine systems. However, the role of stable isotopes as a tool in long-term ecosystem monitoring has not been fully developed.
Bannon, Rebecca O., Roman, Charles T.
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Tracing the Influence of Sewage Nitrogen in a Coastal Ecosystem Using Stable Nitrogen Isotopes

AMBIO: A Journal of the Human Environment, 2005
This paper reviews the use of stable nitrogen isotopes (delta15N) to delineate the influence of sewage nitrogen (N) in coastal ecosystems, drawing extensively on the case of Himmerfjärden, a Baltic Sea bay that receives 15N-enriched tertiary treated sewage that is discharged mainly as dissolved inorganic N (DIN).
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Labelling Compounds with the Stable Isotopes of Nitrogen and Oxygen

2011
In this chapter we consider the methods that have been used to introduce the stable isotopes of nitrogen and oxygen into organic compounds. These isotopes have played an important role both in the study of organic reaction mechanisms and in biosynthesis.
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Nitrogen stable isotopes in streams: effects of agricultural sources and transformations

Ecological Applications, 2009
The nitrogen stable isotope ratio of biological tissue has been proposed as an indicator of anthropogenic N inputs to aquatic ecosystems, but overlap in the isotopic signatures of various N sources and transformations make definitive attribution of processes difficult. We collected primary consumer invertebrates from streams in agricultural settings in
Matthew W, Diebel, M Jake, Vander Zanden
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Model of Nitrogen Source Allocations and Transformations Using Stable Nitrogen Isotopes

World Environmental and Water Resources Congress 2013, 2013
Stream restoration for water quality and nutrient management relies on effective assessment methods that measure the before-and-after improvement of water quality, or lack thereof, from implementation. We present a water quality and nutrient modeling tool for potential use in such applications.
W. I. Ford, J. F. Fox
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Fractionation of nitrogen stable isotopes by ion exchange chromatography

Journal of Radioanalytical and Nuclear Chemistry, 2003
The ion exchange chromatography displacement technique was used for the enrichment of 15N. The runs were conducted in laboratory and bench scales using two systems of columns filled with Wofatit KPS ion exchange resin (medium porosity type). Ammonia NH4+/NH3 aq. was chosen as the isotopic exchange system.
Aguilera Y, Consuegra R, Abreu A, Baldassarre F, Rendueles M   +4 more
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INCORPORATING NITROGEN STABLE ISOTOPES INTO ATMOSPHERIC CHEMISTRY MODELS

2021
The nitrogen stable isotope composition (δ15N) of nitrogen oxides (NOx) may be an effective tool to evaluate the accuracy of the NOx emission inventories, which are based on different assumptions. In order to approach this goal, the understanding of (1) the δ15N(NOx) values of the major emission sources, (2) how atmospheric processes, such as mixing ...
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Stable isotopes of dissolved nitrogen in oceanic waters

2016
Aquatic Sciences Meeting, Aquatic Sciences: Global And Regional Perspectives - North Meets South, 22-27 February 2015, Granada ...
Delgado Huertas, Antonio, Granados, Arsenio, Metcalf, Amanda, Mesa, Elena, Galí, Martí, Simó, Rafel, Fernández-Castro, Bieito, Tell, Elena, Duarte, Carlos M.   +8 more
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