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Inorganic geochemistry of sedimentary rocks in the catchment of river Thuringian Saale during the last 600 Ma

A literature retrieval was performed for whole rock geochemical analyses of sedimentary, magmatic and metamorphic rocks in the catchment of River Thuringian Saale for the past 600 Ma. Considering availability and coincidence with paleontological an facies data the following indicators seem suitable to detect environmental and climatic changes: biogenic P for Paleoproductivity, STI Index for weathering intensity, Ni/Co-ratio for redox conditions, relative enrichments of Co, Ba and Rb versus crustal values for volcanic activity at varying differentiation. The Mg/Ca-ratio as proxy for salinity is applicable in evaporites. The binary plot Nb/Y versus Zr/TiO2 indicates a presently eroded volcanic level of the Bohemian Massif as catchment area for the Middle Bunter, whereas higly differentiated volcanics provided source material for Neoproterozoic greywackes. A positive Eu-anomaly is limited to the Lower Bunter and implies mafic source rocks perhaps formerly located in the Bohemian Massif.

Mean Deep Ocean volume-weighted stacks

Mean Deep Ocean stacked records weighted by ocean basin volume are also provided for: benthic δ18O, MDOT and δ18Oseawater and compiled from records described for the non-weighted stacks. The weighted stacks were created using basin weights defined using fixed deep ocean volume fractions following the volumetric approach of Lisiecki and Stern (2016) (see their Table S2), and renormalised to unity at each time step to reflect the ocean volume represented by the available records.

Atlantic, Pacific and Mean Deep Ocean temperature and δ¹⁸Oseawater stacks

Stacked deep-water (>2500m) deconvolved benthic Mg/Ca–δ18O records spanning the past 1.5 Myr for: the North Atlantic comprising IODP Site U1385 [Uvigerina peregrina and Globobulimina affinis] and DSDP Site 607 [Cibicidoides wuellerstorfi, Oridorsalis umbonatus, and Uvigerina spp.] (Sosdian and Rosenthal, 2009; Ford et al., 2016); the Pacific incorporating ODP Sites 1123 [Uvigerina spp.] (Elderfield et al., 2012) and Site 1208 [Uvigerina spp.] (Ford and Raymo, 2020); and, Mean Deep Oceans including all of the above plus ODP Site 1094 [Melonis pompilioides] (Hasenfratz et al., 2019). To investigate changes in abyssal ocean density stratification across the Middle Pleistocene Transition estimates of deep-water temperature and δ18Oseawater were generated with error propagation using PSU Solver in MATLAB (Thirumalai, Quinn and Marino, 2016). PSU Solver-derived δ18O, temperature and δ18Oseawater records for each site were interpolated on a 3 kyr interval and bootstrapped. Stacks were manually created by first identifying gaps in each site's original data and then averaging the means and errors across each age interval.

Determination of log KOC values according to OECD TG 106

The report presents a study on the environmental behaviour of melamine (CAS: 108-78-1), investigated in adsorption and desorption experiments with five different soils. As part of the study, the organic carbon-normalized adsorption coefficients (Koc values) were determined. Koc describes the relative distribution of a substance between soil and water, normalized to the fraction of organic carbon in the soil. Under the CLP Regulation, Koc is a key parameter for evaluating the mobility of substances in the aquatic environment, and thus provides an essential basis for environmental hazard classification. The results of this study deliver important data for assessing melamine with respect to its classification in the regulatory hazard categories PMT (persistent, mobile, toxic) and vPvM (very persistent, very mobile). Veröffentlicht in Texte | 149/2025.

Determination of log KOC values according to OECD TG 106

The report presents a study on the environmental behaviour of three benzotriazoles – 1H-benzotriazole (CAS 95-14-7), 4-methylbenzotriazole (CAS 29878-31-7), and 5-methylbenzotriazole (CAS 136-85-6) – investigated in adsorption and desorption experiments with five different soils. As part of the study, the organic carbon-normalized adsorption coefficients (Koc values) were determined. Koc describes the relative distribution of a substance between soil and water, normalized to the fraction of organic carbon in the soil. Under the CLP Regulation, Koc is a key parameter for evaluating the mobility of substances in the aquatic environment, and thus provides an essential basis for environmental hazard classification. The results of this study deliver important data for assessing the three benzotriazoles with respect to their classification in the regulatory hazard categories PMT (persistent, mobile, toxic) and vPvM (very persistent, very mobile). Veröffentlicht in Texte | 148/2025.

Laser ablation inductively coupled mass spectrometry of eudialyte to investigate the magmatic stability and elements distribution between eudialyte and peralkaline silica-undersaturated melts

Eudialyte and eudialyte-group minerals (EGM) are unique tracers of peralkaline silica-undersaturated melts. They receive global interest as potential resources for high-field-strength elements (HFSE) (e. g. Zr, Nb, Ta, and rare-earth elements; REE), i. e. critical materials for modern technologies. The main condition for magmatic crystallization of eudialyte and EGM is that the concentration of Zr in parental melt should reach the saturation level. Thus, the solubility of eudialyte was studied in the system at temperatures between 750 and 1000 °C and pressures of 100 and 200 MPa. Liquid phases in run products are eudialyte, parakeldyshite and albite. Eudialyte is stable between 750 and 900 °C, and decomposes to parakeldyshite between 900 and 1000°C. Eudialyte crystallization in dry peralkaline silica-undersaturated melt at 750 and -850 °C requires minimum 0.2-0.22 wt.% ZrO2 in the melt. In melts with high amounts of dissolved H2O the saturation level in within the same temperature interval is much higher, at 1.1-2.85 wt.% ZrO2. Thus, peralkaline melts should be dry to crystallize EGM at ZrO2 concentrations between 0.2 and 0.3 wt.%. LA-ICP-MS results show that REEs and HFSEs are strongly compatible with eudialyte as the eudialyte-melt distribution coefficients (D) vary from 2 to 90. Light REEs and especially La tend to have lower D values than heavy REEs. The data reflect that the concentrations of REEs and HFSEs in the eudialyte solid solution are mainly determined by the Zr concentrations in the melt: the lowest partition coefficients are observed in experiments with the highest eudialyte solubility, i.e., in experiments at high temperature and with H2O content This data report is the supplement to the publication (Nikolenko et al., 2024, in prep.). This study presents a combined experimental research, EPMA and LA ICP-MS studies. This document describes the LA-ICP-MS analytical methods, sample preparation and the in-situ LA-ICP-MS element composition of eudialyte and peralkaline silica-undersaturated melts. Eudialyte, which was used in experiments is a natural mineral, that had been collected from a pegmatite body on mount Eveslogchorr in the Khibina Massif, Kola Peninsula, Russia. Eudialyte crystals were crushed in a mortar and clear, inclusion-free fragments were hand-picked under a binocular. Three synthetic glasses with variable Na-Al molar ratios were prepared from finely ground mixtures of silica (p.a., Merck®), aluminium oxide (γ-phase, 99.97%, 3 μm powder, Alfa Aesar®), and sodiumcarbonate (anhydrous, p.a., Merck®). The glasses were synthesized by sintering starting mixtures in a platinum crucible first at 900 °C for 1 hour, then crushing of the sintered material and remelting it two or three times at 1100-1200 °C for about 2 hours, with intermediate quenching in cold water and grinding the crushed glass fragments to the grain size of less than 1 mm. Mixtures of the Khibina eudialyte and one of the synthetic glasses were ground in agate mortar to fine powders under acetone, dried at 100 °C for 2 hours, loaded into platinum capsules (outer and inner diameters 4.4 and 4.0 mm respectively) and welded shut. In some runs, distilled water (Merck, Suprapur®) was added to the starting charges before welding.

Abfallnotifizierungen

Bearbeitung von Notifizierungen grenzüberschreitender Abfallverbringung sowie Überwachung und Kontrolle gemäß Verordnung (EG) Nr. 1013/2006 und Abfallverbringungsgesetz. Es sind Daten zu den einzelnen Notifizierungen vorhanden (Abfallarten, Mengen, Versandstaaten, etc.).

Schulen Chemnitz

Durch Adress-Punkte symbolisch dargestellte Schulen.

GeolDG: Indirekte Aufschlüsse in der Ausschließlichen Wirtschaftszone Deutschlands

Der Datensatz umfasst die Nachweisdaten von indirekten Aufschlüssen, die vom Geologiedatengesetz betroffen sind und sich innerhalb der ausschließlichen Wirtschaftszone Deutschlands befinden.

Bestimmung von Edelmetallen und ihren Spezies in biologischen Proben mittels Atomfluoreszenzspektrometrie, Laserablation mit ICP-MS und Atomabsorptionsspektrometrie

Die anthropogene Verbreitung der Edelmetalle durch die Nutzung vornehmlich als Katalysator in der chemischen Industrie und in Kraftfahrzeugen hat bereits zu messbaren Veraenderungen der Edelmetallgehalte in Umweltproben gefuehrt. Ein systematischer Ueberblick ueber die Veraenderungen und deren Auswirkungen auf Lebewesen ist noch nicht machbar, da zu wenige Untersuchungen vorliegen. Fuer das Element Platin sind, zumindest fuer die Verbreitung in der Umwelt, einige Aussagen verfuegbar. Fuer die Metalle Palladium, Rhodium und Iridium sind Untersuchungen nur ansatzweise zu finden. Praktisch keine Aussagen sind ueber die Bindungszustaende zu erhalten. Angaben ueber die vorkommenden Metallspezies sind aber fuer die Kenntnis der Wirkungsmechanismen dieser Metalle auf Lebewesen wichtig. Ziel des Projektes ist die Charakterisierung von Umweltproben, speziell biologischer Proben, bezueglich ihrer Gehalte an Edelmetallen und deren Spezies.

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