API src

Found 987 results.

Related terms

Carbonate chemistry parameters calculated from measured pH, total alkalinity, salinity and temperature in the alkalization mesocosms of a chronic Ostrea edulis alkalinity-enhancement exposure experiment

This dataset contains calculated carbonate chemistry parameters, including the concentrations of dissolved CO2, HCO3-, CO32- and dissolved inorganic carbon, the fugacity and partial pressure of CO2 and the saturation states of aragonite (Ωarag) and calcite (Ωcalc), for the alkalization mesocosms. Values were calculated from pH, total alkalinity, salinity and temperature measured between 17 April and 19 June 2024, using the seacarb package (Orr et al., 2018) in R (V. 4.3.2). Measured pH values, which refer to the NBS scale, were first converted to the total scale using the total proton activity coefficient fH of Takahashi et al. (1982), lowering pH by 0.12 to 0.13 units across the measured salinity and temperature range. Calculations used the carbonic acid dissociation constants of Lueker et al. (2000), the bisulfate dissociation constant of Dickson (1990), the hydrogen fluoride constant of Perez & Fraga (1987), total boron after Uppström (1974) and the aragonite and calcite solubility products of Mucci (1983), all evaluated at in situ temperature and salinity. The conversion from the NBS to the total scale carries a residual uncertainty of about 0.01 to 0.02 pH units, because the liquid junction potential between the dilute calibration buffers and seawater is not fully captured by fH. This propagates to an uncertainty of roughly 5 to 15 % in calculated pCO2 and a correspondingly smaller uncertainty in the saturation states.

Carbonate chemistry parameters calculated from measured pH, total alkalinity, salinity and temperature in the exposure mesocosms of a chronic Ostrea edulis alkalinity-enhancement exposure experiment

This dataset contains calculated carbonate chemistry parameters, including the concentrations of dissolved CO2, HCO3-, CO32- and dissolved inorganic carbon, the fugacity and partial pressure of CO2 and the saturation states of aragonite (Ωarag) and calcite (Ωcalc), for the exposure mesocosms. Values were calculated from pH, total alkalinity, salinity and temperature measured between 8 May and 10 July 2024, using the seacarb package (Orr et al., 2018) in R (V. 4.3.2). Measured pH values, which refer to the NBS scale, were first converted to the total scale using the total proton activity coefficient fH of Takahashi et al. (1982), lowering pH by 0.12 to 0.13 units across the measured salinity and temperature range. Calculations used the carbonic acid dissociation constants of Lueker et al. (2000), the bisulfate dissociation constant of Dickson (1990), the hydrogen fluoride constant of Perez & Fraga (1987), total boron after Uppström (1974) and the aragonite and calcite solubility products of Mucci (1983), all evaluated at in situ temperature and salinity. The conversion from the NBS to the total scale carries a residual uncertainty of about 0.01 to 0.02 pH units, because the liquid junction potential between the dilute calibration buffers and seawater is not fully captured by fH. This propagates to an uncertainty of roughly 5 to 15 % in calculated pCO2 and a correspondingly smaller uncertainty in the saturation states.

Rückstandsgehalte und Verteilung von subtherapeutischen Antibiotika in Feedlot-Böden

Feedlots sind v.a. in Nordamerika verbreitete Tierproduktionsbetriebe mit intensivster Freilandhaltung. Es wird vermutet, dass Feedlots Brennpunkte einer Umweltbelastung mit pharmazeutischen Antibiotika sind, da große Tierbestände gehalten werden, die regelmäßig Antibiotika erhalten. Es wurden Bodenproben von einer Grasland-Kontrolle sowie Boden- und Tierdung-Proben von Bodenprofilen eines gewerblichen und eines experimentellen Feedlots entnommen und analysiert. Rückstände der üblicherweise verwendeten Antibiotika Sulfamethazin, Chlortetracyclin und Tylosin wurden mit unterschiedlichen Konzentrationen in Dung, Boden und Wasser gefunden. Die Ergebnisse weisen auf eine nicht unerhebliche Persistenz, Tiefenverlagerung und insbesondere Oberflächenabfluss der Antibiotika Sulfamethazin und Chlortetracyclin hin.

Release of hexavalent chromium from ore processing residues and the potential of biochar for chromium immobilization in polluted soils

Chromium (Cr) is introduced into the environment by several anthropogenic activities. A striking ex-ample is the area around Kanpur in the Indian state of Uttar Pradesh, where large amounts of Cr-containing wastes have been recently illegally deposited. Hexavalent Cr, a highly toxic and mobile contaminant, is present in significant amounts in these wastes, severely affecting the quality of sur-roundings soils, sediments, and ground waters. The first major goal of this study is to clarify the solid phase speciation of Cr in these wastes and to examine its leaching behavior. X-ray diffraction and synchrotron-based X-ray absorption spectroscopy techniques will be employed for quantitative solid phase speciation of Cr. Its leaching behavior will be studied in column experiments performed at un-saturated moisture conditions with flow interruptions simulating monsoon rain events. Combined with geochemical modeling, the results will allow the evaluation of the leaching potential and release kinetics of Cr from the waste materials. The second major goal is to investigate the spatial distribution, speciation, and solubility of Cr in the rooting zone of chromate-contaminated soils surrounding the landfills, and to study the suitability of biochar as novel soil amendment for mitigating the deleterious effects of chromate pollution. Detailed field samplings and laboratory soil incubation studies will be carried out with two agricultural soils and biochar from the Kanpur region.

Neue Technologien zur Wiederverwertung von Altbaustoffen, Neue Technologien zur Schadstoffinertisierung und Rueckgewinnung von Rohstoffen

Erzeugung hochwertiger Schlacken aus schmelzfluessigen Rueckstaenden von Hochtemperatur-Muellverbrennungsanlagen (HT-MVA). Qualitative und quantitative Bestimmung der Schwefelkreislaeufe im Siemens Schwel-Brenn-Verfahren (Kooperation mit Siemens, KWU). Modellzusammensetzungen fuer den Glasanteil in Muellverbrennungsschlacken: Anwendung der Viskositaets- und Kristallisationsdaten der Modellglaeser auf den Glasanteil in realen HT-MV-Schlacken.

German Eco-Cycle and Waste Policies: The Current State of German Mandatory Deposit System and End-of-life-Vehicles (Automotive Shredder Residue - ASR)

Continuous hyperspectral above-water radiometric data along RV HEINCKE cruise HE681

This data set was recorded by permanently installed above-water radiometry onboard RV HEINCKE. Five TriOS instruments are installed at the top of the foremast: one irradiance sensor (ACC) to measure the incoming solar irradiance as a reference, 2 radiometers (ARC) to measure the incoming sky radiance, 2 radiometers (ARC) to measure the sea-surface leaving radiance. One set of radiometers is pointed to 45° starboard and the other to 45° port. The data were recorded with the MSDA-XE software in 15s interval and transferred via cloud. The data were then reformatted and processed with the community processor HyperCP. Ancillary data was taken from the mastertrack and Insightics DSHIP extraction. Data were processed for coastal conditions using sky/sunglint correction by Zhang et al. (2017), NIR residual correction using Ruddick et al. 2006, and BRDF correction based on IOP-based approach by Lee.

Electron diffraction patterns and HR-EBSD data from laboratory deformed olivine aggregates

This dataset is supplemental to the paper Wiesman et al. (submitted) and contains data on the density of dislocations and their stress fields in olivine rocks deformed via laboratory experiments. The data were used to investigate how the quality of diffraction patterns obtained via electron backscatter diffraction (EBSD) affect the stress maps and geometrically necessary dislocation (GND) maps obtained via analysis with high-angular resolution electron backscatter diffraction (HR-EBSD). These results can be used to optimize the patterns collected during EBSD to reduce noise in the HR-EBSD analysis. Data are provided in a zip folder and include: • Measurements of lattice orientation via EBSD: six raw .ctf files and six processed .ctf files of regions mapped with HR-EBSD • Examples of electron backscatter diffraction patterns used to calculate radial power spectra: 12 .tiff files of diffraction patterns • Densities of geometrically necessary dislocations from the HR-EBSD analysis: six .txt files of processed data • Residual stress heterogeneity also determined from HR-EBSD analysis: six .txt files of processed data Data types and the number of frames averaged are also indicated in the file names. Files are organized into folders by the number of frames averaged. A full description is available in the data description file.

Pflanzenschutzmittelrueckstaende in der deutschen Brotgetreideernte

a) Feststellung des Gehalts an Pflanzenschutzrueckstaenden in verschiedenen Getreidearten. Untersuchung des Abbaus bzw. des Metabolismus waehrend der Lagerung und waehrend der Verarbeitung. b) Analytische Bestimmung der Pestizide in Getreide und in Mahlprodukten in Abhaengigkeit von Lagerung und Verarbeitung einschliesslich Backprozess. Feststellung von Stoffwechselprodukten. c) Mehrjaehrige, laufende Untersuchungen in Anpassung an neue Pflanzenschutzmittel und neue analytische Verfahren.

GC-MS-Analyse zur Unterstuetzung der Charakterisierung und Reinigung kontaminierter Waesser und Schlaemme

In der Bundesrepublik Deutschland, insbesondere im Umfeld Thueringens gibt es eine Vielzahl von Altlasten, die mit den verschiedenen Verfahren der Bodenreinigung saniert werden koennen. Bei kostenguenstigen Verfahren, wie z.B. der Bodenwaesche, bleiben bestimmte Schadstoffraktionen als hochbelastete Waesser und Schlaemme zurueck. Soweit es bei dem derzeitigen Stand der Technik wirtschaftlich moeglich ist, koennen sie weiter aufbereitet werden. Hier kommen verschiedene Verfahren, u.a. Einsatz von Aktivkohle, Hochleistungsbiologie, Strippen, und die chemische Oxidation zum Einsatz. Zur Entwicklung weiterer Verfahren zu diesem Zweck ist es erforderlich, begleitende Untersuchungen der einzelnen Verfahrensschritte zu taetigen, um somit zur Verfahrensoptimierung beizutragen und neuartigen Verfahren den Weg zur Einsatzfaehigkeit zu ebnen. Das Forschungsprojekt soll das Profil der Fachhochschule Erfurt in der Umweltanalytik erweitern sowie Gelegenheit geben, ein ueber den Durchschnitt hinausreichendes Fachwissen zu etablieren. Es soll insbesondere dem Fachbereich Versorgungstechnik, der den Aufbaustudiengang Umwelttechnik mit beinhaltet, ermoeglichen, Wirtschaftsunternehmen vor allem in Thueringen Kooperationsmoeglichkeiten anzubieten, die diese fuer die Entwicklung geeigneter Erzeugnisse, Verfahren und Anlagen nutzen koennen, um somit ihre Wettbewerbsfaehigkeit zu steigern.

1 2 3 4 5 … 97 98 99