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Calcium carbonate (CaCO3), total organic carbon (TOC) contents and carbon-to-nitrogen ratio (C/N) from composite sediment core BIS-2000

The data set bundle comprises geochemical, XRF core scanning and pollen data from composite sediment core BIS-2000, which was compiled from two parallel sediment cores (BIS-1 and BIS-3) obtained near Bispingen, northern Germany (53.071528°N, 9.989861°E, 82.0 m). BIS-2000 comprises Last Interglacial (Eemian) to early Last Glacial (Weichselian) palaeolake deposits, which cover the section between 15.55 and 30.68 m composite depth. The data set Bispingen BIS-2000 geochemistry contains calcium carbonate (CaCO3) and total organic carbon (TOC) contents (expressed as per cent of sediment dry weight) as well as carbon-to-nitrogen ratio (C/N) data. Analyses were carried out at the GFZ German Research Centre for Geosciences in Potsdam, Germany, on the section between 15.55 and 30.72 m composite depth. The CaCO3 content was calculated from the total inorganic carbon (TIC) content, which was measured using a STRÖHLEIN Coulomat 702. In addition, measurements of the total carbon (TC) and total nitrogen (TN) contents were carried out using a LECO CNS-2000 elemental analyser. TOC was calculated as the difference between TC and TIC and C/N was calculated as the mass ratio between TC and TN.

Schwerpunktprogramm (SPP) 527: Bereich Infrastruktur - Integrated Ocean Drilling Program/Ocean Drilling Program (IODP/ODP), Teilprojekt: Sedimente des Melvillesees: Ein Zeitfenster in die präholozäne Glazialgeschichte des Laurentidischen Eisschildes (Akronym: MELSED)

Der Melvillesee ist ein Fjordsee, der sich in der letzten Eiszeit am Rande des hochdynamischen Laurentidischen Eisschildes (LIS) befand. Die obersten 10 m der insgesamt ca. 300-400 m Seesedimente haben die postglaziale Geschichte der letzten 10000 Jahre aufgezeichnet. In diesem dicken Sedimentpaket dürfte der See die Klimageschichte bis weit zurück vor das letzte Glazial gespeichert haben und würde sich daher als exzellentes Klimaarchiv anbieten. Um diesen Sachverhalt zu klären, wurde im Sommer 2019 eine Expedition mit dem FS Maria S. Merian (MSM84) unternommen. Während dieser Expedition wurden Sedimentkerne gezogen sowie ein dichtes Netz von hydroakustischen Messungen durchgeführt. Anhang der Sedimentkerne und der Sedimentecholot-Daten kann man fünf verschiedene Schichten im Untergrund des Sees erkennen: (I) post-glaziale Sedimente; (II) Sedimente aus der Zeit des Eisrückzuges; (III) Sedimente, die mit großer Wahrscheinlichkeit in einem subglazialen See unterhalb des aufschwimmenden LIS abgelagert wurden. Darunter finden sich (IV) wiederum schön geschichtete Sedimente, die aus einem früheren eisfreien Zeitraum stammen dürften, vermutlich MIS5, MIS4 oder die erste Hälfte des MIS3. Als unterste Schichte ist das Grundgestein (V) zu erkennen. Unsere Sedimentkerne enthalten Sedimente aus I und II sowie aus dem obersten Bereich von III. Im Rahmen dieses Projektes schlagen wir vor, die post-glazialen Sedimente sowie diejenige vom Rückzug des LIS genauer zu untersuchen, um daran Paläoklimaschwankungen sowie die Rückzugsgeschichte des LIS zu rekonstruieren. In einem zweiten Schritt möchten wir auch die Sedimente analysieren, die vom subglazialen See zu stammen, um diesen besser zu charakterisieren und um zu testen, ob auch diese Sedimente Klimaschwankungen aufgezeichnet haben. Um diese Fragen zu beantworten, werden wir die Sedimentkerne zuerst mit zerstörungsfreien Methoden wie CT-Scanning, Multisensor-Core-Logging und XRF-Scanning untersuchen. Danach werden ausgewählte Kernabschnitte beprobt. Mit Hilfe von Radiokarbondatierungen und paläomagnetischen Messungen werden wir ein Altersmodell erstellen können. Mit einer Kombination der zerstörungsfreien Messungen mit Einzelprobenmessungen (TIC, TOC, Korngröße, XRD, WD-XRF) werden wir die in den Kernen enthaltene paläoklimatologische Information entschlüsseln. Hierbei werden wir einen Schwerpunkt auf die Entwicklung von Proxies legen, die geeignet sind, die vergangenen Vorstöße und Rückzüge des LIS zu rekonstruieren. Falls wir zeigen können, dass die Sedimente des Melvillesees tatsächlich ein Archiv für Klimageschichte auch jenseits des Holozäns sind, dann empfiehlt sich der See als ein Hauptziel einer zukünftigen amphibischen Tiefbohrung von IODP und ICDP. Diese würde mit dem Ziel abgeteuft, die Dynamik des LIS zu rekonstruieren.

Field parameters and biochemical soil properties from NEP 1, NEP 2, NEP 3, Nördlingen, southern Germany

Soil physical-biogeochemical analyses were carried out on profiles NEP1, NEP2 and NEP3. Soil TC and TN were determined by CNS analysis, and total organic carbon (TOC) was determined by the difference between total inorganic carbon (TIC) and TC. Carbonate (CaCO₃) content was measured volumetrically using a Calcimeter and on air-dried, sieved (< 2 mm) and ground (ball mill) samples. The pH-values were measured on samples of profiles NEP1, NEP2, NEP3, which had less than 2% CaCO₃ content. Stable isotope ratios of δ¹³C and δ¹⁵N were analysed for the differentiation of C3 and C4 plants and the cultivation of legumes. The analyses were performed on air-dried, sieved (< 2mm) and ground (ball mill) samples. For ¹³C analysis, the soil samples were decarbonised with 10% HCl. In the field, separate samples were collected for the NEP1 and NEP2 profiles (28 samples in total) for analysis of urease activity and microbial biomass carbon (Cmic). Samples were stored at -18°C. Urease activity (enzyme analysis) is used to provide information on the input of urea and animal excrement. The mutual relationship between urease and Cmic was used to show and understand the past and present input of urea into the soil.

TERENO Monitoring data from Lake Tiefer See and Lake Czechowskie (2012-2017)

This dataset resulted from a parallel monitoring at two lakes, Lake Tiefer See (near Klocksin, TSK; 53° 35.5’ N, 12° 31.8’ E; 62 masl; N Germany) and Lake Czechowskie (Jezioro Czechowskie, JC; 53° 52.4’ N, 18° 14.3’ E; 108 masl; N Poland), and includes four different type of data for both locations: (i) sediment cores microfacies data, (ii) sediment fluxes and composition, (iii) selected water column data, and (iv) selected meteorological information obtained on site. This dual lake monitoring set-up was established in 2012 with the aim to investigate seasonal sedimentation and varve forming processes in detail. The datasets are provided in individual *.csv files, per type of data and per lake. The thin section data from surface sediment cores comprises the thicknesses of the most recent calcite varves’ sub-layers: spring diatom sub-layer, summer calcite sub-layer, and autumn/winter re-suspension sub-layer. The sediment flux data was obtained from sediment traps located in different water depths (epi- and hypolimnion), and the sediment composition is given by the fluxes of total organic carbon (TOC), calcium carbonate (as calculated from total inorganic carbon; TIC), and diatoms & inorganic matter. The water column data comprises water temperature from stationary loggers, and dissolved oxygen measured in ~ 1 meter depth-resolution. The meteorological data includes daily averages of air temperature and mean wind-speed, and summed daily rainfall. Further details about the sampling and analytical methods, data acquisition, and processing are given in Roeser et al. (2021; http://doi.org/10.1111/bor.12506).

Porewater and sediment geochemistry of five temperate Swiss lakes

We sampled sediments from three water depths in five lakes in central Switzerland: Lake Lucerne, Lake Zurich, Lake Zug, Lake Baldegg, and Lake Greifen. All took place in June and July of 2016. Three sublittoral stations differing in water depth and bottom water O2 concentrations were sampled. Per each lake station, one 60-mm diameter and 3–4 150-mm diameter gravity cores (UWITEC, AT) were taken from boats or motorized platforms. The thin cores were used for analyses of radionuclides, X-ray fluorescence, grain size, and archiving (one-half). Wide cores were used as follows: the core with the least disturbed sediment surface was used for microsensor measurements (O2, pH). Sediment porewater samples were obtained by rhizons (0.2 μm pore size, Rhizosphere) from a designated core with pre-drilled holes that were taped during coring for analyses of dissolved anions and cations including redox sensitive elements. Sediment samples for cell counts, methane concentration analyses, and physical property determinations (porosity, bulk density, dry density, water content) were taken from a third core using sterile cut-off syringes. Samples for solid-phase carbon analyses (TOC, total inorganic carbon (TIC)) were also taken from this core.

AMaLiS - Alternative Materialien und Komponenten für aprotische Lithium/Sauerstoff-Batterien: Ionische Flüssigkeiten und Titancarbid-basierte Gasdiffusionselektroden in Kombination mit geschützten Li-Anoden, AMaLiS - Alternative Materialien und Komponenten für aprotische Lithium/Sauerstoff-Batterien: Ionische Flüssigkeiten und Titancarbid-basierte Gasdiffusionselektroden in Kombination mit geschützten Li-Anoden

Im Rahmen des Projektes AMaLiS sollen die Potenziale der Li/Sauerstoff-Technologie auf Basis der eigenen Vorarbeiten der Konsortialpartner und bisherigen Kenntnisse weiterentwickelt werden. Die derzeit in der Forschung eingesetzten Materialien weisen nur eine unzureichende Stabilität in diesem Batteriesystem auf. Entsprechend sollen in diesem Projekt zum einen die aprotischen Elektrolyte durch ionische Flüssigkeiten (IL) und zum anderen der Kohlenstoff in der GDE durch Titancarbid (TiC) ersetzt werden. Dafür sind die Verbundpartner IOLITEC und H.C. Starck (assoziiert) essentiell, da sie neben dem Know-How und der Bereitstellung der Materialien auch Aspekte eines späteren Scale-up bzgl. der eingesetzten Rohstoffe bis in den Processing-Maßstab einbringen. Durch den Einsatz von IL, die stabil gegen Lithium sind und TiC, das stabil gegen Sauerstoff ist, lässt sich eine Zelle konstruieren, die ein idealer Ansatzpunkt zur Validierung der Leistungsfähigkeit der Batterie ist. Die assoziierten Partner H.C. Starck, Schaeffler und Varta bilden in dem vorliegenden Vorhaben eine nützliche und sinnvolle Ergänzung zur Vervollständigung der Wertschöpfungskette.

AMaLiS - Alternative Materialien und Komponenten für aprotische Lithium/Sauerstoff-Batterien: Ionische Flüssigkeiten und Titancarbid-basierte Gasdiffusionselektroden in Kombination mit geschützten Li-Anoden, AMaLiS - Alternative Materialien und Komponenten für aprotische Lithium/Sauerstoff-Batterien: Ionische Flüssigkeiten und Titancarbid-basierte Gasdiffusionselektroden in Kombination mit geschützten Li-Anoden

Bulk geochemistry of composite sediment core ROD11 from the crater basin of Rodderberg, Germany

Bulk geochemistry characterizes sediment composition and supports palaeoclimatic reconstruction of glacial/interglacial cycles for the Middle Pleistocene sediment record from the crater basin of Rodderberg, Germany. A sediment record measuring 72.8 m in length was retrieved by employing wire-line drilling techniques, utilising 3 m-long liners, from the silted-up crater basin of Rodderberg (East Eifel Volcanic Field) in the vicinity of the city of Bonn, Germany. The composite record ROD11 was subjected to continuous analysis for bulk geochemistry (total carbon, total nitrogen, total sulphur) with 10 cm spatial resolution employing a CNS analyser (EuroEA, Eurovector). Additionally, the analysis of total organic carbon was carried out with the same setup but after the destruction of carbonates with 3% and 20% sulphuric acid. The difference between total carbon and total organic carbon yields total inorganic carbon, a proxy parameter for carbonates. The calculation of organic matter was performed by multiplication of total organic carbon with a value of 2.13, in accordance with the methodology proposed by Dean (1974). The calculation of carbonaceous matter was accomplished by multiplying total inorganic carbon values with 8.33, in order to account for the stoichiometric mass change from C to CaCO3. Minerogenic matter was determined as the difference between 100 and the sum of organic matter and carbonaceous matter. These parameters enhance the palaeoclimatic interpretation for the past 430 ka. Valued by multiple dating techniques, this terrestrial record provides an environmental reconstruction since the Middle Pleistocene.

Energieforschung (e!MISSION), HiPoCat: Highly Porous Cathodes for Lithium Air Batteries

The aim of the HiPoCat project (Highly Porous Cathodes for Lithium-Air Batteries) is to evaluate metal-organic frameworks (MOFs) and zeolitic imidazolate frameworks (ZIFs) for use as new precursors for cathode materials for Li-air batteries. Through pyrolysis of the highly microporous MOFs and ZIFs, cathode materials with high electronic conductivities, reactivity, and corrosion resistance will be synthesized. Furthermore, thermal analysis and kinetic modelling approaches will be used to determine the pyrolysis parameters leading to optimal porosities. The cathode materials that are developed in this work will be combined with suitable electrolytes and electrolyte additives to assemble Li-air batteries which display specific capacities, coulombic efficiencies, and rate-capabilities which are significantly higher than those of the conventionally used carbon-based cathodes. Additionally, the porous gas-diffusion cathodes will be produced using a lower number of synthesis steps and environmentally-friendly aqueous solvents, which will be a technological first in Austria.

TOC, TIC, TN and TS contents and stable isotope signatures (δ13C of TOC, δ15N, δ34S) of fine-grained saltmarsh deposits of the barrier island Spiekeroog at the southern North Sea Coast

The dataset compiles total organic carbon (TOC), total inorganic carbon (TIC), total nitrogen (TN) and total sulfur (TS) contents and stable isotope signatures (δ13C of TOC, δ15N, δ34S) of fine-grained deposits (clay, loam) over sandy subsoils of the saltmarsh of the barrier island Spiekeroog at the southern North Sea coast. Sampling was performed in September 2016 along three transects spanning from the high saltmarsh to the pioneer zone. At each sample point, soil samples were taken from the first 5 cm of the upper part (top samples) and from the deepest 5 cm of the lower part (bottom samples) of the fine-grained deposit. If the fine-grained deposit layer had a thickness < 10 cm, only one bulk soil sample (single samples) was taken for the depth range equal to the deposit thickness. Samples were ground to fine powder. TIC was measured on oven-dried samples coulometrically with an Analytik Jena multi EA 4000 analyzer. The total carbon (TC), TN, and TS were analyzed using a Thermo Scientific Flash EA Isolink Elemental Analyzer. The TOC contents were calculated as the difference between TC and TIC. TOC, TN, and TS contents are reported based on the original dry mass. For isotope analysis, dried and homogenized samples were weighed in tin cups and combusted in a Thermo Scientific Flash EA Isolink Elemental Analyzer, connected to a Thermo Finnigan MAT 253 gas mass spectrometer via a Thermo Conflo IV split interface. The δ13C values of TOC were measured after decalcification of the ground powders with p. a. grade HCl. The TN and δ34S analysis were carried out on a separate aliquot of sample powder. The isotope results are given in the conventional δ-notation.

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