دورية أكاديمية
Improved accuracy and precision in δ15 NAIR measurements of explosives, urea, and inorganic nitrates by elemental analyzer/isotope ratio mass spectrometry using thermal decomposition.
العنوان: | Improved accuracy and precision in δ15 NAIR measurements of explosives, urea, and inorganic nitrates by elemental analyzer/isotope ratio mass spectrometry using thermal decomposition. |
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المؤلفون: | Lott MJ; IsoForensics, Inc., 421 Wakara Way, Suite 100, Salt Lake City, UT, 84108, USA., Howa JD; IsoForensics, Inc., 421 Wakara Way, Suite 100, Salt Lake City, UT, 84108, USA., Chesson LA; IsoForensics, Inc., 421 Wakara Way, Suite 100, Salt Lake City, UT, 84108, USA., Ehleringer JR; IsoForensics, Inc., 421 Wakara Way, Suite 100, Salt Lake City, UT, 84108, USA. |
المصدر: | Rapid communications in mass spectrometry : RCM [Rapid Commun Mass Spectrom] 2015 Aug 15; Vol. 29 (15), pp. 1381-8. |
نوع المنشور: | Journal Article |
اللغة: | English |
بيانات الدورية: | Publisher: John Wiley And Sons Ltd Country of Publication: England NLM ID: 8802365 Publication Model: Print Cited Medium: Internet ISSN: 1097-0231 (Electronic) Linking ISSN: 09514198 NLM ISO Abbreviation: Rapid Commun Mass Spectrom Subsets: PubMed not MEDLINE |
أسماء مطبوعة: | Publication: Chichester : John Wiley And Sons Ltd Original Publication: London, UK : Heyden, c1987- |
مستخلص: | Rationale: Elemental analyzer systems generate N(2) and CO(2) for elemental composition and isotope ratio measurements. As quantitative conversion of nitrogen in some materials (i.e., nitrate salts and nitro-organic compounds) is difficult, this study tests a recently published method - thermal decomposition without the addition of O(2) - for the analysis of these materials. Methods: Elemental analyzer/isotope ratio mass spectrometry (EA/IRMS) was used to compare the traditional combustion method (CM) and the thermal decomposition method (TDM), where additional O(2) is eliminated from the reaction. The comparisons used organic and inorganic materials with oxidized and/or reduced nitrogen and included ureas, nitrate salts, ammonium sulfate, nitro esters, and nitramines. Previous TDM applications were limited to nitrate salts and ammonium sulfate. The measurement precision and accuracy were compared to determine the effectiveness of converting materials containing different fractions of oxidized nitrogen into N(2). Results: The δ(13) C(VPDB) values were not meaningfully different when measured via CM or TDM, allowing for the analysis of multiple elements in one sample. For materials containing oxidized nitrogen, (15) N measurements made using thermal decomposition were more precise than those made using combustion. The precision was similar between the methods for materials containing reduced nitrogen. The %N values were closer to theoretical when measured by TDM than by CM. The δ(15) N(AIR) values of purchased nitrate salts and ureas were nearer to the known values when analyzed using thermal decomposition than using combustion. Conclusions: The thermal decomposition method addresses insufficient recovery of nitrogen during elemental analysis in a variety of organic and inorganic materials. Its implementation requires relatively few changes to the elemental analyzer. Using TDM, it is possible to directly calibrate certain organic materials to international nitrate isotope reference materials without off-line preparation. (Copyright © 2015 John Wiley & Sons, Ltd.) |
تواريخ الأحداث: | Date Created: 20150707 Date Completed: 20150910 Latest Revision: 20150707 |
رمز التحديث: | 20240628 |
DOI: | 10.1002/rcm.7229 |
PMID: | 26147477 |
قاعدة البيانات: | MEDLINE |
تدمد: | 1097-0231 |
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DOI: | 10.1002/rcm.7229 |