Heavy hydrogen in the stratosphere [PDF]
Atmospheric Chemistry and Physics, 2003 We report measurements of the deuterium content of molecular hydrogen (H2) obtained from a suite of air samples that were collected during a stratospheric balloon flight between 12 and 33 km at 40º N in October 2002.
T. Röckmann, T. S. Rhee, A. Engel
doaj +3 more sources
Electrochemical hydrogen isotope exchange of amines controlled by alternating current frequency. [PDF]
Faraday Discuss, 2023 Here, we report an electrochemical protocol for hydrogen isotope exchange (HIE) at -C(sp3)-H amine sites. Tetrahydroisoquinoline and pyrrolidine are selected as two model substrates because of their different proton transfer (PT) and hydrogen atom ...
Behera N +5 more
europepmc +2 more sources
Recent Progresses in Stable Isotope Analysis of Cellulose Extracted from Tree Rings
Plants, 2021 In this work, the challenges and progression in stable isotope investigation, from the analytical tools and technical sample preparation procedures to the dendroclimatological experiments, were reviewed in terms of their use to assess tree physiological ...
Silviu-Laurentiu Badea +2 more
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Alkali-metal bases in catalytic hydrogen isotope exchange processes. [PDF]
Catal Sci Technol, 2023 he preparation of compounds labelled with deuterium or tritium has become an essential tool in a range of research fields. Hydrogen isotope exchange (HIE) offers direct access to said compounds, introducing these isotopes in a late stage. Even though the
Tortajada A, Hevia E.
europepmc +2 more sources
Isotope Effects on Chemical Shifts in the Study of Hydrogen Bonds in Small Molecules
Molecules, 2022 This review is giving a short introduction to the techniques used to investigate isotope effects on NMR chemical shifts. The review is discussing how isotope effects on chemical shifts can be used to elucidate the importance of either intra- or ...
Poul Erik Hansen
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Nanocatalyzed Hydrogen Isotope Exchange
Accounts of Chemical Research, 2021 Recently, hydrogen isotope exchange (HIE) reactions have experienced impressive development due to the growing importance of isotope containing compounds in various fields including materials and life sciences, in addition to their classical use for mechanistic studies in chemistry and biology.
Lepron, Marco +5 more
openaire +4 more sources
Effects of alkalinity and salinity at low and high light intensity on hydrogen isotope fractionation of long-chain alkenones produced by Emiliania huxleyi [PDF]
Biogeosciences, 2017 Over the last decade, hydrogen isotopes of long-chain alkenones have been shown to be a promising proxy for reconstructing paleo sea surface salinity due to a strong hydrogen isotope fractionation response to salinity across different environmental ...
G. M. Weiss +6 more
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A consistent molecular hydrogen isotope chemistry scheme based on an independent bond approximation [PDF]
, 2009 The isotopic composition of molecular hydrogen (H<sub>2</sub>) produced by photochemical oxidation of methane (CH<sub>4</sub>) and Volatile Organic Compounds (VOCs) is a key quantity in the global isotope budget of (H<sub>2 ...
Sub Atmospheric physics and chemistry +8 more
core +1 more source
Multideuteration of Nitroaromatics by Silver-Catalyzed Hydrogen-Isotope Exchange [PDF]
, 2022 A silver-catalyzed deuteration of nitroaromatics has been achieved using D2O as the deuterium source. Distinct from the well-established directing group guided hydrogen-isotope exchange, the protocol showed an interesting deuteration pattern, where ...
Jianfei, Bai +9 more
core +1 more source
Global modelling of H2 mixing ratios and isotopic compositions with the TM5 model [PDF]
, 2011 The isotopic composition of molecular hydrogen (H2) contains independent information for constraining the global H2 budget. To explore this, we have implemented hydrogen sources and sinks, including their stable isotopic composition and isotope ...
Langenfelds, R.L. +16 more
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