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  • 11
    Publikationsdatum: 2024-04-26
    Beschreibung: A total of 556 samples (3 cm average sample spacing) were collected from the 12 m long Winsenberg section in order to reconstruct a floating timescale using cyclostratigraphic methods and to investigate paleoclimatic dynamics using selected elemental ratios. Samples were measured as a powder covered with Chemplex film on a Bruker S1 Titan 800 portable XRF at the University of Münster with the following settings: 40 kV, 20 mA, no filters, 75 s. Spectra were deconvoluted in Bruker Artrax software, and linearly calibrated using a set of 10 sedimentary standards of known composition and 11 calcite-quart mixtures. The composition of these standards is also included. Selected elemental ratios were tuned via the methods described in the accompanying manuscript, and are included in this dataset as well.
    Schlagwort(e): Age, relative; Astrochronology; Carbon isotopes; Cyclostratigraphy; Devonian; Fieldwork; Frasnian-Famennian; Germany; HAND; Kellwasser Crisis; Portable X-Ray Fluorescence; Rhenish Massif; Sampling by hand; Silicon dioxid/Calcium oxide ratio; TOC; Winsenberg; Winsenberg_2021; XRD
    Materialart: Dataset
    Format: text/tab-separated-values, 1132 data points
    Standort Signatur Erwartet Verfügbarkeit
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  • 12
    Publikationsdatum: 2024-04-26
    Beschreibung: A total of 34 samples (35 cm average sample spacing) were analysed for organic carbon d13C in order to identify the two characteristic positive excursions associated with the Lower and Upper Kellwasser Events. Measurements were carried out at the Analytical, Environmental and Geo-Chemistry Research Group (AMGC) of the Vrije Universiteit Brussel (Belgium). The samples were decarbonated with 10% HCl in two steps, rinsed with milliQ water, and dried in an oven at 50°C. Total organic carbon (TOC) contents and δ13Corg compositions were determined on a Euro EA 150 Elemental Analyzer (CHNS) - Euro Vector HT-PyrOH combustion system coupled to a Nu-Instruments Horizon 2 isotope ratio mass spectrometer.
    Schlagwort(e): Astrochronology; Carbon, organic, total; Carbon, organic, total, standard deviation; Carbon isotopes; Cyclostratigraphy; Date of determination; Devonian; Element analyser CHNS; Fieldwork; Frasnian-Famennian; Germany; HAND; Kellwasser Crisis; Portable X-Ray Fluorescence; Rhenish Massif; Sample ID; Sampling by hand; Stratigraphic height; TOC; Winsenberg; Winsenberg_2021; XRD
    Materialart: Dataset
    Format: text/tab-separated-values, 240 data points
    Standort Signatur Erwartet Verfügbarkeit
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  • 13
    Publikationsdatum: 2024-04-26
    Beschreibung: This high-resolution multiproxy dataset was collected in Fall 2021 from the Winsenberg road cut section (Rhenish Massif, Germany, 51°22'17.1N, 8°47'51.0E) in order to construct a precession-scale paleoclimatological record of the Kellwasser Crisis at the Devonian Frasnian-Famennian boundary (ca. 372 Ma). Samples were collected every 3 cm from a ca. 12 m long section spanning both the Lower and Upper Kellwasser black shales. The lithology of the section consists of marls, shales, and carbonates, and represents a shelf basin setting south of the paleocontinent Laurentia. Rock samples were collected with a hammer and chisel and subsequently pulverized with a dremel drill to a particle size of 〈180 microns. A total of 556 samples (3 cm average sample spacing) were collected from the 12 m long Winsenberg section in order to reconstruct a floating timescale using cyclostratigraphic methods and to investigate paleoclimatic dynamics using selected elemental ratios. Samples were measured as a powder covered with Chemplex film on a Bruker S1 Titan 800 portable XRF at the University of Münster with the following settings: 40 kV, 20 mA, no filters, 75 s. Spectra were deconvoluted in Bruker Artrax software, and linearly calibrated using a set of 10 sedimentary standards of known composition and 11 calcite-quart mixtures. The composition of these standards is also included. Selected elemental ratios were tuned via the methods described in the accompanying manuscript, and are included in this dataset as well. A total of 152 samples (8 cm average sample spacing) were analysed for carbonate d13C in order to identify the two characteristic positive excursions associated with the Lower and Upper Kellwasser Events. Measurements on powdered samples weighing 120-150 μg were carried out on a ThermoScientific Delta V Plus mass spectrometer at the University of Münster, using an in-house standard (Kabonat-1; δ13C = 1.46‰, δ18O = -1.19‰) for calibration and an external standard (NBS-19; δ13C = 1.95‰, δ18O = -2.20‰) for long-term performance monitoring. A total of 34 samples (35 cm average sample spacing) were analysed for organic carbon d13C in order to identify the two characteristic positive excursions associated with the Lower and Upper Kellwasser Events. Measurements were carried out at the Analytical, Environmental and Geo-Chemistry Research Group (AMGC) of the Vrije Universiteit Brussel (Belgium). The samples were decarbonated with 10% HCl in two steps, rinsed with milliQ water, and dried in an oven at 50°C. Total organic carbon (TOC) contents and δ13Corg compositions were determined on a Euro EA 150 Elemental Analyzer (CHNS) - Euro Vector HT-PyrOH combustion system coupled to a Nu-Instruments Horizon 2 isotope ratio mass spectrometer. The results were calibrated using two international standards, IAEA-C6 (sucrose: δ13C = -10.45‰) and IA-R068 (soy protein: δ13C = -25.22‰), together with reference material IVA33802151, which is calibrated against these international standards (organic-rich sediment: δ13C = -28.85‰). This calibration was verified with a further reference material, IVA33802153 (organic-rich soil: δ13C = -22.88‰). 4 samples were analysed for their relative clay mineral content. Glass smear slides were prepared and measured on a Philips X'Pert Modular Powder Diffractometer at the University of Münster, equipped with a Cu anode (1.5405 Å) and operated with the following settings: 45 kV voltage, 40 mA current, 0.02°θ step size, 1 s per measurement step, 3-50°2θ measuring range, 30 runs per sample, and no sample rotation. Note that the data obtained via this analysis is not quantitative.
    Schlagwort(e): Astrochronology; Carbon isotopes; Cyclostratigraphy; Devonian; Fieldwork; Frasnian-Famennian; Germany; Kellwasser Crisis; Portable X-Ray Fluorescence; Rhenish Massif; TOC; Winsenberg; XRD
    Materialart: Dataset
    Format: application/zip, 11 datasets
    Standort Signatur Erwartet Verfügbarkeit
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  • 14
    Publikationsdatum: 2024-04-26
    Schlagwort(e): Astrochronology; Calculated; Carbon isotopes; Cyclostratigraphy; Devonian; Fieldwork; Frasnian-Famennian; Germany; HAND; Kellwasser Crisis; Portable X-Ray Fluorescence; Rhenish Massif; Sampling by hand; Sedimentation rate; Stratigraphic height; TOC; Winsenberg; Winsenberg_2021; XRD
    Materialart: Dataset
    Format: text/tab-separated-values, 24 data points
    Standort Signatur Erwartet Verfügbarkeit
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  • 15
    Publikationsdatum: 2024-04-26
    Beschreibung: 4 samples were analysed for their relative clay mineral content. Glass smear slides were prepared and measured on a Philips X'Pert Modular Powder Diffractometer at the University of Münster, equipped with a Cu anode (1.5405 Å) and operated with the following settings: 45 kV voltage, 40 mA current, 0.02°θ step size, 1 s per measurement step, 3-50°2θ measuring range, 30 runs per sample, and no sample rotation. Note that the data obtained via this analysis is not quantitative.
    Schlagwort(e): Astrochronology; Carbon isotopes; Cyclostratigraphy; Devonian; Fieldwork; Frasnian-Famennian; Germany; HAND; Kellwasser Crisis; Portable X-Ray Fluorescence; Rhenish Massif; Sampling by hand; TOC; Winsenberg; Winsenberg_2021; XRD
    Materialart: Dataset
    Format: application/zip, 387.7 kBytes
    Standort Signatur Erwartet Verfügbarkeit
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  • 16
    Publikationsdatum: 2024-04-26
    Beschreibung: A total of 34 samples (35 cm average sample spacing) were analysed for organic carbon d13C in order to identify the two characteristic positive excursions associated with the Lower and Upper Kellwasser Events. Measurements were carried out at the Analytical, Environmental and Geo-Chemistry Research Group (AMGC) of the Vrije Universiteit Brussel (Belgium). The samples were decarbonated with 10% HCl in two steps, rinsed with milliQ water, and dried in an oven at 50°C. Total organic carbon (TOC) contents and δ13Corg compositions were determined on a Euro EA 150 Elemental Analyzer (CHNS) - Euro Vector HT-PyrOH combustion system coupled to a Nu-Instruments Horizon 2 isotope ratio mass spectrometer. The results were calibrated using two international standards, IAEA-C6 (sucrose: δ13C = -10.45‰) and IA-R068 (soy protein: δ13C = -25.22‰), together with reference material IVA33802151, which is calibrated against these international standards (organic-rich sediment: δ13C = -28.85‰). This calibration was verified with a further reference material, IVA33802153 (organic-rich soil: δ13C = -22.88‰).
    Schlagwort(e): Astrochronology; Carbon isotopes; Cyclostratigraphy; Date of determination; Devonian; Element analyser CHNS; Fieldwork; Frasnian-Famennian; Germany; HAND; Kellwasser Crisis; Portable X-Ray Fluorescence; Rhenish Massif; Sample ID; Sampling by hand; Stratigraphic height; TOC; Winsenberg; Winsenberg_2021; XRD; δ13C, organic carbon; δ13C, organic carbon, standard deviation
    Materialart: Dataset
    Format: text/tab-separated-values, 170 data points
    Standort Signatur Erwartet Verfügbarkeit
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  • 17
    Publikationsdatum: 2024-04-26
    Beschreibung: A total of 556 samples (3 cm average sample spacing) were collected from the 12 m long Winsenberg section in order to reconstruct a floating timescale using cyclostratigraphic methods and to investigate paleoclimatic dynamics using selected elemental ratios. Samples were measured as a powder covered with Chemplex film on a Bruker S1 Titan 800 portable XRF at the University of Münster with the following settings: 40 kV, 20 mA, no filters, 75 s. Spectra were deconvoluted in Bruker Artrax software, and linearly calibrated using a set of 10 sedimentary standards of known composition and 11 calcite-quart mixtures. The composition of these standards is also included. Selected elemental ratios were tuned via the methods described in the accompanying manuscript, and are included in this dataset as well.
    Schlagwort(e): Age, relative; Astrochronology; Carbon isotopes; Cyclostratigraphy; Devonian; Fieldwork; Frasnian-Famennian; Germany; HAND; Kellwasser Crisis; Portable X-Ray Fluorescence; Rhenish Massif; Sampling by hand; Titanium dioxide/Aluminium oxide ratio; TOC; Winsenberg; Winsenberg_2021; XRD
    Materialart: Dataset
    Format: text/tab-separated-values, 1096 data points
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 18
    Publikationsdatum: 2024-04-26
    Beschreibung: A total of 556 samples (3 cm average sample spacing) were collected from the 12 m long Winsenberg section in order to reconstruct a floating timescale using cyclostratigraphic methods and to investigate paleoclimatic dynamics using selected elemental ratios. Samples were measured as a powder covered with Chemplex film on a Bruker S1 Titan 800 portable XRF at the University of Münster with the following settings: 40 kV, 20 mA, no filters, 75 s. Spectra were deconvoluted in Bruker Artrax software, and linearly calibrated using a set of 10 sedimentary standards of known composition and 11 calcite-quart mixtures. The composition of these standards is also included. Selected elemental ratios were tuned via the methods described in the accompanying manuscript, and are included in this dataset as well.
    Schlagwort(e): Aluminium oxide; Astrochronology; Calcium oxide; Carbon isotopes; Chromium; Cyclostratigraphy; Date of determination; Devonian; Fieldwork; Frasnian-Famennian; Germany; HAND; Iron oxide, Fe2O3; Kellwasser Crisis; Manganese oxide; Number; Phosphorus pentoxide; Portable X-Ray Fluorescence; Potassium oxide; Rhenish Massif; Sample ID; Sampling by hand; Silicon dioxide; Stratigraphic height; Strontium; Titanium dioxide; TOC; Vanadium; Winsenberg; Winsenberg_2021; X-ray fluorescence spectrometry (portable XRF), S1 TITAN Bruker; XRD; Zinc; Zirconium
    Materialart: Dataset
    Format: text/tab-separated-values, 9452 data points
    Standort Signatur Erwartet Verfügbarkeit
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  • 19
    Digitale Medien
    Digitale Medien
    s.l. : American Chemical Society
    Analytical chemistry 54 (1982), S. 1955-1959 
    ISSN: 1520-6882
    Quelle: ACS Legacy Archives
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 20
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 74 (1993), S. 6139-6145 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The effect of the ambient conditions in the growth chamber of the molecular beam epitaxy machine during the growth of GaAs/Al0.35Ga0.65As structures was investigated. Both growth-interrupted (120 s at each heterointerface) and uninterrupted surfaces and interfaces were evaluated using a growth temperature of 580 °C. Two ambient conditions were studied: (a) ∼1×10−10 Torr O2; and (b) ultrahigh vacuum (UHV, ∼5×10−11 Torr, with no intentional introduction of contaminants). A striking difference was observed in both the 1.7 K photoluminescence (PL) spectra of single quantum well (SQW) structures and UHV scanning tunneling microscopy (STM) of surfaces, which were grown under ambient condition (a) as opposed to (b). When consecutive growth-interrupted SQW samples were grown with different well widths (25 and 28 A(ring)) under condition (a), the emission energy splitting into several peaks was observed, indicating discrete thicknesses of the well. However, the peak energies shifted as the laser spot was scanned across each sample. Additionally, the peak energy shifted from sample to sample for the same nominal well width.On the other hand, when SQW samples were grown under condition (b), no variation in the emission energy was observed as the laser was scanned across the sample, or from sample to sample for a given well width. Furthermore, the PL observations are supported by UHV-STM results. UHV-STM images indicated a very rough surface with large islands containing small terraces on top (a bimodal distribution) for condition (a). Conversely, when samples were grown under condition (b), only large islands were observed. For growth interrupted GaAs surfaces, 400 A(ring)×600 A(ring) islands were observed, and for Al0.35Ga0.65As, they were 150 A(ring)×400 A(ring), with a one-monolayer step in between islands. These data are consistent with abrupt interfaces with only a single-mode distribution for growth-interrupted surfaces. On the other hand, UHV-STM images of uninterrupted GaAs surfaces grown under condition (b) showed islands that were 40–60 A(ring) across. Photoluminesce spectra of a similarly grown SQW sample showed only a single broad emission line, consistent with an interface configuration of many steps which are smaller than the exciton diameter. The results show that interface roughness is sensitive to background O2.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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