Correcting for Naturally Occurring Mass Isotopologue Abundances in Stable-Isotope Tracing Experiments with Polymid
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Abundances of Isotopologues and Calibration of CO2 Greenhouse Gas Measurements Pieter P
Atmos. Meas. Tech. Discuss., doi:10.5194/amt-2017-34, 2017 Manuscript under review for journal Atmos. Meas. Tech. Discussion started: 14 February 2017 c Author(s) 2017. CC-BY 3.0 License. Abundances of isotopologues and calibration of CO2 greenhouse gas measurements Pieter P. Tans1,3, Andrew M. Crotwell2,3, and Kirk W. Thoning1,3 1Global Monitoring Division, Earth System Research Laboratory, National Oceanic and Atmospheric 5 Administration, Boulder, Colorado, 80305, USA. 2Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, 80309, USA. 3Central Calibration Laboratory, World Meteorological Organization Global Atmosphere Watch program (WMO/GAW) 10 Correspondence to: Pieter Tans ([email protected]) Abstract We have developed a method to calculate the fractional distribution of CO2 across all of its component isotopologues based on measured δ13C and δ18O values. The fractional distribution can be used with known total CO2 to calculate each component isotopologue individually, in units of mole fraction. The technique is applicable to 15 any molecule where isotopologue-specific values are desired. We used it with a new CO2 calibration system to account for isotopic differences among the primary CO2 standards that define the WMO X2007 CO2 in air calibration scale and between the primary standards and standards in subsequent levels of the calibration hierarchy. The new calibration system uses multiple laser spectroscopic techniques to measure amount of substance fractions 16 12 16 16 13 16 18 12 16 (in mole fraction units) of the three major CO2 isotopologues ( O C O, O C O, and O C O) individually. 20 The three measured values are then combined into total CO2 (accounting for the rare unmeasured isotopologues), 13 18 δ C, and δ O values. -
THE NATURAL RADIOACTIVITY of the BIOSPHERE (Prirodnaya Radioaktivnost' Iosfery)
XA04N2887 INIS-XA-N--259 L.A. Pertsov TRANSLATED FROM RUSSIAN Published for the U.S. Atomic Energy Commission and the National Science Foundation, Washington, D.C. by the Israel Program for Scientific Translations L. A. PERTSOV THE NATURAL RADIOACTIVITY OF THE BIOSPHERE (Prirodnaya Radioaktivnost' iosfery) Atomizdat NMoskva 1964 Translated from Russian Israel Program for Scientific Translations Jerusalem 1967 18 02 AEC-tr- 6714 Published Pursuant to an Agreement with THE U. S. ATOMIC ENERGY COMMISSION and THE NATIONAL SCIENCE FOUNDATION, WASHINGTON, D. C. Copyright (D 1967 Israel Program for scientific Translations Ltd. IPST Cat. No. 1802 Translated and Edited by IPST Staff Printed in Jerusalem by S. Monison Available from the U.S. DEPARTMENT OF COMMERCE Clearinghouse for Federal Scientific and Technical Information Springfield, Va. 22151 VI/ Table of Contents Introduction .1..................... Bibliography ...................................... 5 Chapter 1. GENESIS OF THE NATURAL RADIOACTIVITY OF THE BIOSPHERE ......................... 6 § Some historical problems...................... 6 § 2. Formation of natural radioactive isotopes of the earth ..... 7 §3. Radioactive isotope creation by cosmic radiation. ....... 11 §4. Distribution of radioactive isotopes in the earth ........ 12 § 5. The spread of radioactive isotopes over the earth's surface. ................................. 16 § 6. The cycle of natural radioactive isotopes in the biosphere. ................................ 18 Bibliography ................ .................. 22 Chapter 2. PHYSICAL AND BIOCHEMICAL PROPERTIES OF NATURAL RADIOACTIVE ISOTOPES. ........... 24 § 1. The contribution of individual radioactive isotopes to the total radioactivity of the biosphere. ............... 24 § 2. Properties of radioactive isotopes not belonging to radio- active families . ............ I............ 27 § 3. Properties of radioactive isotopes of the radioactive families. ................................ 38 § 4. Properties of radioactive isotopes of rare-earth elements . -
Chemical and Isotropic Tracers of Natural Gas and Formation Waters in Fractured Shales
Chemical and isotopic tracers of natural gas and formation waters in Note: this document may contain some elements that are not fully fractured shales accessible to users with disabilities. If you need assistance accessing any information in this document, please contact [email protected]. Jennifer McIntosh, Melissa Schlegel, Brittney Bates Department of Hydrology & Water Resources University of Arizona, Tucson AZ EPA Technical Workshop Feb 24-25, 2011 Outline of Presentation 1)) What is the chemical and isotoppgic signature of formation waters and natural gas in fractured shales? 2) How does it compare with shallow drift aquifers, coalbeds, and other deep geologic formations? Illinois Basin-Case Study - 3 organic-rich formations: glacial drift, Penn. coal, & Dev. fractured shale - organicorganic-rich Ordov. ShaleShale, not part ooff this study m 500 20 km Schlegel et al. (in press, 2011, Geochimica et Cosmochimica Acta) Illinois Basin-Case Study - microbial methane in all 3 units - thermogenic methane in shale and coal m 500 20 km Schlegel et al. (in press, 2011, Geochimica et Cosmochimica Acta) Illinois Basin - water & gas samples Shallow aquifers Penn. Coals Dev. Shale Limestone aquifers 9New data (white symbols): Schlegel et al. (in press) 9Previous data (black symbols): McIntosh et al., 2002; Strąpoć et al., 2007, 2008a,b; Coleman et al, 1988 Fingerprint of natural gases 1000000 Shallow Aquifers 100000 High C1/C2, no C3 Coals 10000 1000 Shale 100 10 Shallow aquifers Penn. Coals Dev. Shale Thermogenic gas 1 -80 -75 -70 -65 -60 -55 -50 -45 -40 13 δ CCH4 (ä PDB) 13 9In general, 3 organic-rich units have different gas compositions (C1/C2+C3) and δ C-CH4 values. -
F:\Forensic Geology\Ice Man Isotopes.Wpd
NAME 89.215 - FORENSIC GEOLOGY DEMISE OF THE ICE MAN - ISOTOPIC EVIDENCE I. Introduction Stable and radiogenic isotopic data have been used in a variety of fields to answer a wide range of scientific questions. The nucleus of an atom consists of protons (+1 charge) and neutrons (0 charge), two types of particles that have essentially the same atomic mass. The number of protons in a nucleus determines the element. For example, a nucleus with 1 proton is a hydrogen nucleus, a nucleus with 2 protons is a helium nucleus. Isotopes of an element contain the same number of protons but different numbers of neutrons. For example, there are three isotopes of hydrogen: (1) ordinary hydrogen which contains one proton and no neutrons and has an atomic mass of one; (2) deuterium which contains one proton and one neutron and has an atomic mass of two; and (3) tritium which contains one proton and two neutrons and has an atomic mass of three. The convention used to show the numbers of types of particles in a nucleus is to place the number of protons (called the atomic number) at the bottom left of the element symbol and the number of protons plus neutrons (called the atomic mass) at the upper left of the element symbol. For example, the tritium isotope is 3 shown as 1H . II. Stable isotopes Stable isotopes are not radioactive, they do not spontaneously breakdown to other atoms. In a previous exercise you used radioactive carbon to determine when the Ice Man was killed. There are three isotopes of carbon: (1) carbon 12 which contains 6 protons and 6 neutrons giving an atomic mass of 12; (2) carbon 13 which contains 6 protons and 7 neutrons giving an atomic mass of 13; and (3) carbon 14 which contains 6 protons and 8 neutrons giving an atomic mass of 14. -
Detection of Deuterated Methylcyanoacetylene, CH $ 2
Astronomy & Astrophysics manuscript no. AA202141371_Cabezas ©ESO 2021 June 8, 2021 Detection of deuterated methylcyanoacetylene, CH2DC3N, in TMC-1 ? C. Cabezas1, E. Roueff2, B. Tercero3; 4, M. Agúndez1, N. Marcelino1, P. de Vicente3 and J. Cernicharo1 1 Grupo de Astrofísica Molecular, Instituto de Física Fundamental (IFF-CSIC), C/ Serrano 121, 28006 Madrid, Spain. e-mail: [email protected]; [email protected] 2 LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, 92190 Meudon, France 3 Observatorio Astronómico Nacional (IGN), C/ Alfonso XII, 3, 28014, Madrid, Spain. 4 Centro de Desarrollos Tecnológicos, Observatorio de Yebes (IGN), 19141 Yebes, Guadalajara, Spain. Received; accepted ABSTRACT We report the first detection in space of the single deuterated isotopologue of methylcyanoacetylene, CH2DC3N. A total of fifteen rotational transitions, with J = 8-12 and Ka = 0 and 1, were identified for this species in TMC-1 in the 31.0-50.4 GHz range using the Yebes 40m radio telescope. The observed frequencies were used to derive for the first time the spectroscopic parameters of this 10 −2 deuterated isotopologue. We derive a column density of (8:0±0:4)×10 cm . The abundance ratio between CH3C3N and CH2DC3N 13 is ∼22. We also theoretically computed the principal spectroscopic constants of C isotopologues of CH3C3N and CH3C4H and those of the deuterated isotopologues of CH3C4H for which we could expect a similar degree of deuteration enhancement. However, we 13 have not detected either CH2DC4H nor CH3C4D nor any C isotopologue. The different observed deuterium ratios in TMC-1 are reasonably accounted for by a gas phase chemical model where the low temperature conditions favor deuteron transfer through + reactions with H2D . -
Isotopic Fractionation of Carbon, Deuterium, and Nitrogen: a Full Chemical Study?
A&A 576, A99 (2015) Astronomy DOI: 10.1051/0004-6361/201425113 & c ESO 2015 Astrophysics Isotopic fractionation of carbon, deuterium, and nitrogen: a full chemical study? E. Roueff1;2, J. C. Loison3, and K. M. Hickson3 1 LERMA, Observatoire de Paris, PSL Research University, CNRS, UMR8112, Place Janssen, 92190 Meudon Cedex, France e-mail: [email protected] 2 Sorbonne Universités, UPMC Univ. Paris 6, 4 Place Jussieu, 75005 Paris, France 3 ISM, Université de Bordeaux – CNRS, UMR 5255, 351 cours de la Libération, 33405 Talence Cedex, France e-mail: [email protected] Received 6 October 2014 / Accepted 5 January 2015 ABSTRACT Context. The increased sensitivity and high spectral resolution of millimeter telescopes allow the detection of an increasing number of isotopically substituted molecules in the interstellar medium. The 14N/15N ratio is difficult to measure directly for molecules con- taining carbon. Aims. Using a time-dependent gas-phase chemical model, we check the underlying hypothesis that the 13C/12C ratio of nitriles and isonitriles is equal to the elemental value. Methods. We built a chemical network that contains D, 13C, and 15N molecular species after a careful check of the possible fraction- ation reactions at work in the gas phase. Results. Model results obtained for two different physical conditions that correspond to a moderately dense cloud in an early evolu- tionary stage and a dense, depleted prestellar core tend to show that ammonia and its singly deuterated form are somewhat enriched 15 14 15 + in N, which agrees with observations. The N/ N ratio in N2H is found to be close to the elemental value, in contrast to previous 15 + models that obtain a significant enrichment, because we found that the fractionation reaction between N and N2H has a barrier in + 15 + + 15 + the entrance channel. -
Mass Spectrometric Separation and Quantitation of Overlapping Isotopologues
Mass Spectrometric Separation and Quantitation of Overlapping Isotopologues. H2O/HOD/D2O and H2Se/HDSe/D2Se Mixtures Juris Meija and Zoltan Mester Institute for National Measurement Standards, National Research Council Canada, Ottawa, Ontario, Canada Alessandro D’Ulivo Laboratory of Instrumental Analytical Chemistry, Institute for Chemical and Physical Processes, Research area of Pisa, National Research Council of Italy, Pisa, Italy Three conceptually different mathematical methods are presented for accurate mass spectro- metric determination of H2O/HOD/D2O and H2Se/HDSe/D2Se concentrations from mix- tures. These are alternating least-squares, weighted two-band target entropy minimization, and a statistical mass balance model. The otherwise nonmeasurable mass spectra of partially deuterated isotopologues (HOD and HDSe) are mathematically constructed. Any recorded isotopologue mixture mass spectra are then deconvoluted by least-squares into their compo- nents. This approach is used to study the H2O/D2O exchange reaction, and is externally validated gravimetrically. The H2O/D2O exchange equilibrium constant is also measured from the deconvoluted 70 eV electron impact GC/MS data (K ϭ 3.85 Ϯ 0.03). (J Am Soc Mass Spectrom 2006, 17, 1028–1036) © 2006 American Society for Mass Spectrometry ` ϩ sotopologues are compounds that differ in isotopic rapid isotope-exchange equilibrium 2HOD H2O composition only, such as H2O and D2O. These com- D2O. Ipounds play an important role in analytical chemistry, Using the best available commercial high-resolution especially in quantitative analysis where most of the mass spectrometers, one can possibly address the H2O/ ⌬ Ͼ modern internal quantitation methods are based on isoto- HOD/D2O system (requiring m/ m 12,000 to fully ϩ ·ϩ pologues. -
A Novel High-Mass Resolution Gas-Source Mass Spectrometer Facility at Ucla
47th Lunar and Planetary Science Conference (2016) 2238.pdf A NOVEL HIGH-MASS RESOLUTION GAS-SOURCE MASS SPECTROMETER FACILITY AT UCLA. Edward D. Young1, Issaku E. Kohl1, Kaitlyn McCain1, Junko Isa1, and Douglas Rumble III2, 1Department of Earth, Planetary, and Space Sciences, University of California Los Angeles, Los Angeles, CA, USA ([email protected]), 2Geophysical Laboratory, 5251 Broad Branch Rd. NW, Washington DC 20015-1305, USA. Introduction: Gas-source isotope ratio mass spec- Oxygen Isotopes: Analyses of extraterrestrial trometry is one of the primary methods for obtaining samples for precise and accurate 18O/16O and 17O/16O, the highest precision isotope ratio measurements of yielding diagnostic Δ′17O values, has been hampered geological and atmospheric samples. It is the standard historically by the presence of NF+ interfering with 33 + for triple oxygen isotope ratio analysis of meteorites, O2 at mass/charge 33 in the mass spectrum. The for example. However, until very recently, advances Panorama instrument can be used to eliminate this in- in this important technology have been limited. terference by virtue of its high mass resolution (Figure Here we describe a unique and novel isotope ratio 2). In a companion abstract, we demonstrate the ad- mass spectrometer (IRMS), the Nu Instruments Pano- vantages of ground-truthing extraterrestrial oxygen rama, developed explicitly for high-mass-resolution isotope ratio measurements of rocks with this method. analysis of isotopologue ratios of gas samples. We have shown recently that this instrument improves the reliability of oxygen isotope analyses at the highest precision and accuracy. In addition, it offers the pro- spects for developing the foundations for using multi- ply-substituted gas species (CH4, N2, O2) as tracers of atmospheric processes and geochemical cycles that should prove useful for extraterrestrial environments as flight instrumentation (e.g., TILDAS) improves. -
Automatic Isotopologue Normalization for Metabolic Tracer Analysis Sophie Trefely1,2* , Peter Ashwell1 and Nathaniel W
Trefely et al. BMC Bioinformatics (2016) 17:485 DOI 10.1186/s12859-016-1360-7 SOFTWARE Open Access FluxFix: automatic isotopologue normalization for metabolic tracer analysis Sophie Trefely1,2* , Peter Ashwell1 and Nathaniel W. Snyder1 Abstract Background: Isotopic tracer analysis by mass spectrometry is a core technique for the study of metabolism. Isotopically labeled atoms from substrates, such as [13C]-labeled glucose, can be traced by their incorporation over time into specific metabolic products. Mass spectrometry is often used for the detection and differentiation of the isotopologues of each metabolite of interest. For meaningful interpretation, mass spectrometry data from metabolic tracer experiments must be corrected to account for the naturally occurring isotopologue distribution. The calculations required for this correction are time consuming and error prone and existing programs are often platform specific, non-intuitive, commercially licensed and/or limited in accuracy by using theoretical isotopologue distributions, which are prone to artifacts from noise or unresolved interfering signals. Results: Here we present FluxFix (http://fluxfix.science), an application freely available on the internet that quickly and reliably transforms signal intensity values into percent mole enrichment for each isotopologue measured. ‘Unlabeled’ data, representing the measured natural isotopologue distribution for a chosen analyte, is entered by the user. This data is used to generate a correction matrix according to a well-established algorithm. The correction matrix is applied to labeled data, also entered by the user, thus generating the corrected output data. FluxFix is compatible with direct copy and paste from spreadsheet applications including Excel (Microsoft) and Google sheets and automatically adjusts to account for input data dimensions. -
Mass Fraction and the Isotopic Anomalies of Xenon and Krypton in Ordinary Chondrites
Scholars' Mine Masters Theses Student Theses and Dissertations 1971 Mass fraction and the isotopic anomalies of xenon and krypton in ordinary chondrites Edward W. Hennecke Follow this and additional works at: https://scholarsmine.mst.edu/masters_theses Part of the Chemistry Commons Department: Recommended Citation Hennecke, Edward W., "Mass fraction and the isotopic anomalies of xenon and krypton in ordinary chondrites" (1971). Masters Theses. 5453. https://scholarsmine.mst.edu/masters_theses/5453 This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected]. MASS FRACTIONATION AND THE ISOTOPIC ANOMALIES OF XENON AND KRYPTON IN ORDINARY CHONDRITES BY EDWARD WILLIAM HENNECKE, 1945- A THESIS Presented to the Faculty of the Graduate School of the UNIVERSITY OF MISSOURI-ROLLA In Partial Fulfillment of the Requirements for the Degree MASTER OF SCIENCE IN CHEMISTRY 1971 T2572 51 pages by Approved ~ (!.{ 1.94250 ii ABSTRACT The abundance and isotopic composition of all noble gases are reported in the Wellman chondrite, and the abundance and isotopic composition of xenon and krypton are reported in the gases released by stepwise heating of the Tell and Scurry chondrites. Major changes in the isotopic composition of xenon result from the presence of radio genic Xel29 and from isotopic mass fractionation. The isotopic com position of trapped krypton in the different temperature fractions of the Tell and Scurry chondrites also shows the effect of isotopic fractiona tion, and there is a covariance in the isotopic composition of xenon with krypton in the manner expected from mass dependent fractiona tion. -
Hydrogen Isotope Exchanges Between Water and Methanol in Interstellar Ices a Faure, M Faure, P Theulé, E Quirico, B Schmitt
Hydrogen isotope exchanges between water and methanol in interstellar ices A Faure, M Faure, P Theulé, E Quirico, B Schmitt To cite this version: A Faure, M Faure, P Theulé, E Quirico, B Schmitt. Hydrogen isotope exchanges between water and methanol in interstellar ices. Astronomy and Astrophysics - A&A, EDP Sciences, 2015, 584, pp.A98. 10.1051/0004-6361/201526499. hal-01452286 HAL Id: hal-01452286 https://hal.archives-ouvertes.fr/hal-01452286 Submitted on 1 Feb 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. A&A 584, A98 (2015) Astronomy DOI: 10.1051/0004-6361/201526499 & c ESO 2015 Astrophysics Hydrogen isotope exchanges between water and methanol in interstellar ices A. Faure1,2,M.Faure1,2, P. Theulé3, E. Quirico1,2, and B. Schmitt1,2 1 Univ. Grenoble Alpes, IPAG, 38000 Grenoble, France e-mail: [email protected] 2 CNRS, IPAG, 38000 Grenoble, France 3 Aix-Marseille Université, PIIM UMR-CNRS 7345, 13397 Marseille, France Received 8 May 2015 / Accepted 22 September 2015 ABSTRACT The deuterium fractionation of gas-phase molecules in hot cores is believed to reflect the composition of interstellar ices. -
Isotope Geochemistry of Carbonate Dissolution and Reprecipitation in Soils R
SOIL SCIENCE Vol. 122, No. I Copyright © 1976 by The Williams &Wilkin s Co. I'rintedin U.S.A. ISOTOPE GEOCHEMISTRY OF CARBONATE DISSOLUTION AND REPRECIPITATION IN SOILS W. SALOMONS' AND W. G. MOOK Laboratoryof Inorganic Chemistry'.The University of Groningen, Zernikelaan, Paddepoel,Groningen, the Netherlands, and Physics Laboratory, University of Groningen, Westersingel 34, Groningen, the Netherlands Received for publication May 21, 197/> ABSTRACT The processes of dissolution and reprecipitation of carbonates in soils developed on carbonate rocks, loess-derived soils, and marine clay soils were studied with the methods of stable isotope geochemistry. Between 10 and 50 percent of the carbonates present in the upper part of soils developed on carbonate rocks are newly formed. In loess-derived soils and in marine clay soils, up to 100 percent of the carbonates present may be newly formed. The efficiency of the dissolution-reprecipitation process varies between 10 and 30 percent. In the salt marsh investigated the dissolution is caused by the action of biogenic carbon dioxide. INTRODUCTION pies by treatment with 95 percent orthophos- Carbonates are an important constituent of phoric acid. The presence of organic matter in the soil. The processes they are subject to are most soil samples analyzed introduces an error dissolution followed by (partial) reprecipita in both the carbon and oxygen isotopic composi tion. Reprecipitation can be easily recognized tion of less than 0.37„o (Salomons 1974). when it results in macroscopic concretions. Since this small shift has no influence on our However, when the newly formed carbonates conclusions, the time-consuming step of remov are finely divided they are difficult to detect by ing the organic matter from the sample prior to conventional methods.