Concept

Isotope

Publications associées (245)

Stable carbon and oxygen isotope compositions of extant crinoidal echinoderm skeletons

Anders Meibom, Jaroslaw Hubert Stolarski

The variability of delta C-13 and delta O-18 was determined within the columnal facet of individual ossicles, within different regions of skeletons and within bulk skeletons of extant stalked crinoids. Isotopic compositions of individual ossicles may vary ...

2012

Pulsed 86Sr-labeling and NanoSIMS imaging to study coral biomineralization at ultra-structural length scales

Anders Meibom, Jaroslaw Hubert Stolarski, Isabelle Domart-Coulon

A method to label marine biocarbonates is developed based on a concentration enrichment of a minor stable isotope of a trace element that is a natural component of seawater, resulting in the formation of biocarbonate with corresponding isotopic enrichments ...

Springer-Verlag2012

NMR and Electron Paramagnetic Resonance Studies of [Gd(CH3CN)(9)](3+) and [Eu(CH3CN)(9)](2+): Solvation and Solvent Exchange Dynamics in Anhydrous Acetonitrile

Lothar Helm, Gabriella Eva Bodizs

Homoleptic acetonitrile complexes [Gd(CH3CN)(9)]Al(OC(CF3)(3))(4) and [Eu(CH3CN)(9)]Al(OC(CF3)(3))(4) have been studied in anhydrous acetonitrile by N-14- and H-1 NMR relaxation as well as by X- and Q-band EPR. For each compound a combined analys ...

2012

Dynamic Nuclear Polarization Enhanced Solid-State NMR Spectroscopy of Functionalized Metal-Organic Frameworks

David Lyndon Emsley, Aaron James Rossini, Moreno Lelli

A matter of minutes: Dynamic nuclear polarization (DNP) is applied to enhance the signal of solid-state NMR spectra of metal-organic framework (MOF) materials. The signal enhancement enables the acquisition of high-quality 1D 13C solid-state NMR spectra, 2 ...

WILEY-BLACKWELL2012

Multiple Isomers and Protonation Sites of the Phenylalanine/Serine Dimer

Thomas Rizzo, Ulrich Lorenz

Our investigation of the phenylalanine/serine (Phe/Ser) protonated dimer suggests that the intermolecular interaction between the two amino acids is more complex than could have been anticipated from previous studies of similar systems. Isomer-specific inf ...

2012

Efficient First-Principles Calculation of the Quantum Kinetic Energy and Momentum Distribution of Nuclei

Michele Ceriotti

Light nuclei at room temperature and below exhibit a kinetic energy which significantly deviates from the predictions of classical statistical mechanics. This quantum kinetic energy is responsible for a wide variety of isotope effects of interest in fields ...

2012

Dynamic Nuclear Polarization NMR Spectroscopy of Microcrystalline Solids

David Lyndon Emsley, Aaron James Rossini, David Benjamin Roger Antoine Gajan

Dynamic nuclear polarization (DNP) solid-state NMR has been applied to powdered microcrystalline solids to obtain sensitivity enhancements on the order of 100. Glucose, sulfathiazole, and paracetamol were impregnated with bis-nitroxide biradical (bis-cyclo ...

AMER CHEMICAL SOC2012

The sticking probability of D2O-water on ice: Isotope effects and the inﬂuence of vibrational excitation

Rainer Beck, Régis Bisson, Phil Morten Hundt

The present study measures the sticking probability of heavy water (D2O) on H2O- and on D2O-ice and probes the inﬂuence of selective OD-stretch excitation on D2O sticking on these ices. Molecular beam techniques are combined with infrared laser excitation ...

American Institute of Physics2012

Building materials as intrinsic sources of sulphate: A hidden face of salt weathering of historical monuments investigated through multi-isotope tracing (B, O, S)

Christophe Gosselin

Sulphate neoformation is a major factor of degradation of stone monuments. Boron, sulphur and oxygen isotope signatures were investigated for five French historical monuments (Bourges, Chartres and Marseille cathedrals, Chenonceau castle, and Versailles ga ...

2011

A multi-proxy, high-resolution record of peatland development and its drivers during the last millennium from the subalpine Swiss Alps

Edward Mitchell, Mariusz Lamentowicz

We present a record of peatland development during the last 1000 years from Mauntschas mire in the eastern Swiss Alps (Upper Engadine valley; 1818 m a.s.l.) inferred from testate amoebae (pH and depth to the water table (DWT) reconstructions), stable oxyge ...

2011

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