• CITATION DATABASE
    IRMS Anwendungen
    in der Forschung

Eine Welt voller Anwendungen

Entdecken Sie die vielfältigen Anwendungsmöglichkeiten von IRMS in der Forschung

Unsere Kunden nutzen unsere Geräte für erstaunliche Forschungsprojekte. Über eine große Bandbreite an Applikationsbereichen wird die Stabilisotopenanalyse (IRMS) eingesetzt, um die Mikro- und Makro-Kreisläufe der Elemente Kohlenstoff, Sauerstoff, Stickstoff, Wasserstoff und Schwefel in komplexen chemischen, physischen und biologischen Prozessen zu untersuchen und verstehen.

Wir haben großes Interesse an der Forschung unserer Kunden und sind stolz, dass mit Hilfe unserer Geräte kontinuierlich neue Forschungsergebnisse erzielt werden und unser kollektives Wissen erweitert wird. Mit über 600 installierten IRMS Geräten weltweit werden regelmäßig neue Publikationen veröffentlicht. Auf dieser Seite finden Sie einen Auszug der neuesten Veröffentlichungen, die sich auf unsere IRMS Systeme beziehen.

Wenn Sie gerne mit uns erörtern möchten, ob IRMS auch in Ihrem Forschungsgebiet sinnvoll eingesetzt werden kann, oder wenn Sie Ihre Veröffentlichung, in der Sie eines unserer Geräte zur Datenakquisition genutzt haben, zu unserer Datenbank hinzufügen möchten, dann zögern Sie nicht, uns zu kontaktieren.


Filter

824 Ergebnisse:

Zinc Isotope Ratios as Indicators of Diet and Trophic Level in Arctic Marine Mammals
Plos One (2016)
Klervia Jaouen, Paul Szpak, Michael P. Richards

Carbon and nitrogen stable isotope ratios of bone collagen are an established method for dietary reconstruction, but this method is limited by the protein preservation. Zinc (Zn) is found in bioapatite and the isotopic compositions of this element constitute a very promising dietary indicator. The extent of fractionation of Zn isotopes in marine environments, however, remains unknown. We report here on the measurement of zinc, carbon and nitrogen isotopes in 47 marine mammals from the archaeological site of Arvik in the Canadian Arctic. We undertook this study to test and demonstrate the utility of Zn isotopes in recent mammal bone minerals as a dietary indicator by comparing them to other isotopic dietary tracers. We found a correlation between δ66Zn values and trophic level for most species, with the exception of walruses, which may be caused by their large seasonal movements. δ6Zn values can therefore be used as a dietary indicator in marine ecosystems for both modern and recent mammals.

Water concentrations and hydrogen isotope compositions of alkaline basalt hosted clinopyroxene megacrysts and amphibole clinopyroxenites : the role of structural hydroxyl groups and molecular water
Contributions to Mineralogy and Petrology (2016)
Istvan Kovacs, Francois Fourel, Qun-ke Xia, Liu Jia, Etienne Deloule, Istvan Kovacs

The aim of this study was to determine both ‘water’ contents (as OH- and H2O) and δD values of several clinopyroxene samples from alkaline basalts. These parameters were first obtained from five clinopyroxene samples using both the classical ‘off-line’ vacuum extraction technique and the ‘on-line’ high-temperature pyrolysis technique. Blanks measured with the ‘on-line’ gas extraction techniques were low enough to prevent any contamination by atmospheric water vapour. The comparison of data has revealed that our ‘on-line’ procedure is more effective for the extraction of ‘water’ from clinopyroxenes and, consequently, this ‘on-line’ technique was applied to ten additional clinopyroxene samples. Sample δD values cover a similar range from -95‰ to -45‰ (VSMOW) regardless the studied locations, whereas the total ‘water’ content varies from ~115 to ~2570 ppm. The structural hydroxyl content of clinopyroxene samples measured by micro-FTIR spectrometry varies from ~0 to 476 ppm expressed in molecular water equivalent. The total ‘water’ concentrations determined by mass spectrometry differs considerably from structural hydroxyl contents constrained by micro-FTIR, thus indicating that considerable proportion of the ‘water’ may be present in (nano)-inclusions. The structural hydroxyl concentration - apart from clinopyroxenes separated from amphibole clinopyroxenite xenoliths - correlates positively with the δD values of clinopyroxene megacrysts for each locality, indicating that structurally bond hydrogen in clinopyroxenes may have δD values higher than molecular water in inclusions. This implies that that there may be a significant hydrogen isotope fractionation for structural hydroxyl during crystallization of clinopyroxene, while for molecular water there may be no or only negligible isotope fractionation

I-n-Atei palaeolake documents past environmental changes in central Sahara at the time of the “Green Sahara”: Charcoal, carbon isotope and diatom records
Palaeogeography, Palaeoclimatology, Palaeoecology (2016)
Christophe Lécuyer, Anne-Marie Lézine, François Fourel, Françoise Gasse, Florence Sylvestre, Christine Pailles, Christophe Grenier, Yves Travi, Abel Barral

During the ‘Green Sahara event’, water bodies developed throughout the Sahara and Sahel, reflecting the enhanced influence of the Atlantic monsoon rainfall. Major lakes then dried out between 6.5 and 3.5ka. This study investigates land cover change and lacustrine environment during the Holocene at I-n-Atei, Southern Algeria, a desert region lying in the hyperarid core of the Sahara. This site is remarkable by its extent (up to 80km2) and by the exceptional preservation and thickness of the lacustrine deposits (7.2m). I-n-Atei was a lake from 11 to 7.4ka, then it dried out and left place to a swampy environment. Charcoal concentrations show that the surroundings of the lake were vegetated throughout the wet period with two short phases of possible vegetation deterioration associated with a lowering of the lake level at 9.3 and 8.2ka, coeval with well-known dry events in the tropics. The stable carbon isotope record reflects the penetration of C4 herbaceous populations in replacement of the original C3, typical of the regional vegetation at the time of the maximum lake expansion. The δ13C of charcoals increase non-linearly with the 14C-based ages from −24.5‰ to −13.0‰ (V-PDB). Assuming that these extreme values sample both C3 and C4 plant end-members, mass balance calculations suggest that C3 were replaced by C4 plants according to an exponential decay law with a half-life (t1/2) of 850±110years. The replacement of C3 by C4 plants occurred in two main steps: a mixed C3–C4 vegetation of “wooded grassland” type was present from 10ka to 8.4ka while a C4 exclusive vegetation developed after 8.4ka. After the end of the lacustrine phase a catastrophic event (flooding?) provoked the lifting of most of the lacustrine deposits and their re-deposition above the lacustrine sequence.

Synergistic Processing of Biphenyl and Benzoate: Carbon Flow Through the Bacterial Community in Polychlorinated-Biphenyl-Contaminated Soil.
Scientific reports (2016)
Mary-Cathrine Leewis, Ondrej Uhlik, Mary Beth Leigh

Aerobic mineralization of PCBs, which are toxic and persistent organic pollutants, involves the upper (biphenyl, BP) and lower (benzoate, BZ) degradation pathways. The activity of different members of the soil microbial community in performing one or both pathways, and their synergistic interactions during PCB biodegradation, are not well understood. This study investigates BP and BZ biodegradation and subsequent carbon flow through the microbial community in PCB-contaminated soil. DNA stable isotope probing (SIP) was used to identify the bacterial guilds involved in utilizing (13)C-biphenyl (unchlorinated analogue of PCBs) and/or (13)C-benzoate (product/intermediate of BP degradation and analogue of chlorobenzoates). By performing SIP with two substrates in parallel, we reveal microbes performing the upper (BP) and/or lower (BZ) degradation pathways, and heterotrophic bacteria involved indirectly in processing carbon derived from these substrates (i.e. through crossfeeding). Substrate mineralization rates and shifts in relative abundance of labeled taxa suggest that BP and BZ biotransformations were performed by microorganisms with different growth strategies: BZ-associated bacteria were fast growing, potentially copiotrophic organisms, while microbes that transform BP were oligotrophic, slower growing, organisms. Our findings provide novel insight into the functional interactions of soil bacteria active in processing biphenyl and related aromatic compounds in soil, revealing how carbon flows through a bacterial community.

Interaction of coal and oil in confined pyrolysis experiments: Insight from the yields and carbon isotopes of gas and liquid hydrocarbons
Marine and Petroleum Geology (2016)
Erting Li, Changchun Pan, Shuang Yu, Xiaodong Jin, Jinzhong Liu

Isothermal confined (gold capsule) pyrolysis experiments were performed for coal alone, oil alone and coal plus oil with oil/coal ratios ranging from 0.006 to 0.171 at 315 °C, 345 °C and 375 °C, respectively and 50 MPa for 72 h. In the experiment for coal plus oil, the amounts and compositions of hydrocarbon gases are substantially different from those predicted from the results in the experiments for oil alone and coal alone. The results of these experiments demonstrate that kerogen and oil do not crack separately in the experiments of coal plus oil. The interaction between kerogen and oil components leads to the generation of hydrocarbon gases. With oil/coal ratio increasing, the amounts of individual and total hydrocarbon gases decrease at first, and then increase rapidly up to several times those calculated from the yields of these components in the experiments for oil alone and coal alone. The C1/ΣC1–5 ratios of hydrocarbon gases decrease and are increasingly lower than those calculated from the yields of hydrocarbon gases in the experiments for oil alone and coal alone. The amount and carbon isotopes of individual n-alkane demonstrate that the free liquid n-alkanes were incorporated into kerogen and replaced the bound liquid n-alkanes (covalently bonded alkyl groups in kerogen). Carbon isotopes of hydrocarbon gases further suggest that the bound liquid n-alkanes in kerogen preferentially crack into hydrocarbon gases.

Methane-derived authigenic carbonates of mid-Cretaceous age in southern Tibet: Types of carbonate concretions, carbon sources, and formation processes
Journal of Asian Earth Sciences (2016)
Huimin Liang, Xi Chen, Chengshan Wang, Dekun Zhao, Helmut Weissert

Methane-derived authigenic carbonates with distinctive structures and morphologies have been documented worldwide, but they are rarely found from ancient strata in the Eastern Tethys Ocean. The methane-derived authigenic carbonates found in southern Tibet are developed in calcareous or silty shales of mid-Cretaceous age in the Xigaze forearc basin and in the Tethyan Himalaya tectonic zone. The morphology, mineralogy, elemental geochemistry and composition of carbon and oxygen isotopes of these carbonates are studied in detail. The carbonates have nodular, tubular, and tabular morphologies. They are primarily composed of carbonate cement that binds and partly replaces host sediment grains; host siliciclastic sediments are composed mainly of quartz and plagioclase feldspar; a few foraminifers; and framboidal or subhedral to euhedral pyrite. Carbonate cements dominantly are micritic calcite, with minor contribution of dolomite. Nodular concretions are characterized by depleted δ13C values, commonly ranging from −30‰ to −5‰. The δ13C values show a gradual decrease from the periphery to the center, and the CaO, SiO2, Fe2O3, Al2O3, K2O, and TiO2 contents generally show a gradual change. These features indicate that the nodular concretions grew from an early-formed center toward the periphery, and that the carbon source of the nodular concretions was derived from a mixture of methane, methanogenic CO2, and seawater-dissolved inorganic carbon. The tubular concretions are characterized by δ13C values of −8.85‰ to −3.47‰ in the Shangba Section, and −27.37‰ to −23.85‰ in the upper Gamba Section. Unlike the nodular concretions, the tubular concretions show central conduits, which are possible pathways of methane-rich fluids, suggesting that the cementation of tubular concretions begins at the periphery and proceeds inward. Moreover, the tubular concretions show morphological similarity with the methane-derived carbonate chimneys, pipes and slabs reported in present-day cold seep settings. We suggest that the carbon source of the tubular concretions was derived from a mixture of seawater-dissolved inorganic carbon and oxidized methane formed by released hydrate. The tabular concretions are characterized by δ13C values of −21.87‰ to −6.67‰ in the Xiege Sections. These depleted δ13C values suggest that the carbon of the tabular concretions was derived at least in part, from AOM. The tabular concretions are characterized by δ13C values of −28.81‰ to −12.99‰ in the Gamba Section. According to the δ13C values and field observation, we infer that their carbon source was more likely to be a mixture of the oxidized methane formed by released hydrate and seawater-dissolved inorganic carbon.

The Dynamics of Protein Body Formation in Developing Wheat Grain.
Plant biotechnology journal (2016)
Katie L Moore, Paola Tosi, Richard Palmer, Malcolm J Hawkesford, Chris R M Grovenor, Peter R Shewry

Wheat is a major source of protein in the diets of humans and livestock but we know little about the mechanisms that determine the patterns of protein synthesis in the developing endosperm. We have used a combination of enrichment with (15) N glutamine and NanoSIMS imaging to establish that the substrate required for protein synthesis is transported radially from its point of entrance in the endosperm cavity across the starchy endosperm tissues, before becoming concentrated in the cells immediately below the aleurone layer. This transport occurs continuously during grain development but may be slower in the later stages. Although older starchy endosperm cells tend to contain larger protein deposits formed by the fusion of small protein bodies, small highly enriched protein bodies may also be present in the same cells. This shows a continuous process of protein body initiation, in both older and younger starchy endosperm cells and in all regions of the tissue. Immunolabelling with specific antibodies shows that the patterns of enrichment are not related to the contents of gluten proteins in the protein bodies. In addition to providing new information on the dynamics of protein deposition, the study demonstrates the wider utility of NanoSIMS and isotope labeling for studying complex developmental processes in plant tissues. This article is protected by copyright. All rights reserved.
Schlagworte: C , N , soi , EA

Energizing marginal soils – The establishment of the energy crop Sida hermaphrodita as dependent on digestate fertilization, NPK, and legume intercropping
Biomass and Bioenergy (2016)
Moritz Nabel, Vicky M. Temperton, Hendrik Poorter, Andreas Lücke, Nicolai D. Jablonowski

Growing energy crops in marginal, nutrient-deficient soils is a more sustainable alternative to conventional cultivation. The use of energy-intensive synthetic fertilizers needs to be reduced, preferably via closed nutrient loops in the biomass production cycle. In the present study based on the first growing season of a mesocosm experiment using large bins outdoors, we evaluated the potential of the energy plant Sida hermaphrodita to grow in a marginal sandy soil. We applied different fertilization treatments using either digestate from biogas production or a commercial mineral NPK-fertilizer. To further increase independence from synthetically produced N-fertilizers, the legume plant Medicago sativa was intercropped to introduce atmospherically fixed nitrogen and potentially facilitate the production of additional S. hermaphrodita biomass. We found digestate to be the best performing fertilizer because it produced similar yields as the NPK fertilization but minimized nitrate leaching. Legume intercropping increased the total biomass yield by more than 100% compared to S. hermaphrodita single cropping in the fertilized variants. However, it negatively influenced the performance of S. hermaphrodita in the following year. We conclude that a successful establishment of S. hermaphrodita for biomass production in marginal soils is possible and digestate application formed the best fertilization method when considering a range of aspects including overall yield, nitrate leaching, nitrogen fixation of M. sativa, and sustainability over time.

AMS 14C dating at Can Ferrerons, a Roman octagonal building in Premià de Mar, Barcelona
Journal of Archaeological Science: Reports (2016)
Marta Prevosti, Alf Lindroos, Jan Heinemeier, Ramon Coll

A singular Roman dwelling, octagonal in ground-plan, was excavated in the year 2000, in Premià de Mar. It is a freestanding pavilion within a larger settlement called Gran Via-Can Ferrerons. It was not possible to date it archaeologically because the basement trenches did not contain any significant dating artefacts. Archaeological research undertaken into the architectural typology of the monument led us to the hypothesis that the structure is to be interpreted as late Roman luxury domestic housing. It was decided to use AMS 14C dating of the mortar in the masonry. This procedure dates the hardening of the carbonate binder in the mortar, which is the actual time of construction. We present the results of three analyses of mortar samples taken from the walls of the building. Radiocarbon dates coincide with the assumed architectural typology date, the date of the strata excavated at the site, and the date of the construction technique. These matches support the validity of the results (5th and 6th century CE).

Palaeotemperature reconstruction during the Last Glacial from δ18O of earthworm calcite granules from Nussloch loess sequence, Germany
Earth and Planetary Science Letters (2016)
Charlotte Prud'homme, Christophe Lécuyer, Pierre Antoine, Olivier Moine, Christine Hatté, François Fourel, François Martineau, Denis-Didier Rousseau

The Nussloch loess–palaeosol sequence (Rhine Valley, Germany) is considered to be one of the most complete records of the last glacial period in Western Europe due to its very high sedimentation rate and its good chronological control. This sequence is therefore a good framework in which to develop new proxies for palaeoenvironmental reconstructions. In this study, we explore, for the first time, the potential of earthworm calcite granules as a new bio-indicator and climatic proxy of absolute air and soil temperature in the context of Last Glacial loess. These granules are composed of rhomboedric calcite crystals, organized in a radial crystalline structure. As these granules are individually generated by earthworms at a relative fast rate, they are expected to record intra-annual variations in the available sources of oxygen: percolating waters of meteoric origin. We extracted thirty earthworm calcite granules from 11 of 5 cm layers thick from tundra gley and brown soil horizons previously, dated at 45 to 23 ka. Oxygen isotope ratios were measured on each individual granule. The δ18O of calcite granules and interlinked transfer functions between water cycle, air and soil temperatures allowed us to estimate air temperatures ranging from 10 to 12 ±4 ◦C, which most likely reflect the warm periods of the year when earthworms were the most active.