Search

Trace elements play a major role in biogeochemical cycles and oceanographic processes. To determine trace element concentrations, the dissolved and particulate phase are usually separated by filtration. However, the frequently used membrane filtration as well as sample storage can bias the dissolved elemental concentrations by adsorption or desorption/contamination. We present a comparison of two filtration methods for coastal and estuarine water samples (pressure filtration with Nuclepore™ polycarbonate filters, vacuum filtration with DigiFILTER™s) applied to aliquots of a large‐volume coastal water sample that were stored at −18°C or 4°C for up to nine weeks. The filtrates were analyzed by seaFAST‐ICP‐MS for dissolved Cd, Ce, Co, Cu, Dy, Er, Eu, Fe, Ho, La, Mn, Mo, Nd, Pb, Pr, Sm, Tb, U, V, W, Y, and Zn. The filtration blanks of DigiFILTER™s (0.0006 ± 0.0010 ng L−1 for Ho to 110 ± 180 ng L−1 for Zn) were sufficiently low for quantification of all analyzed elements with good repeatability, enabling a fast and reliable filtration of large sample sets of coastal water. However, the findings also highlight the need to measure procedural blanks including the filtration instead of only the instrument blanks to validate results. Measured concentrations of both filtration methods did not differ significantly for Cd, Cu, Mo, U, V, W, Zn but for other investigated elements, the ratio between both methods was up to 1.8 for Ce and 4.1 for Fe. Within nine weeks of storage, the elemental concentrations decreased significantly, resulting in losses of 20% Mn in frozen samples and 63% Pb, 64% Co and 93% Mn in cooled samples. Practitioner Points: Two fast and cheap filtration methods for coastal water samples were compared.Dissolved concentrations of 22 elements were measured by seaFAST‐ICP‐MS.The filtration method is important in addition to filter pore size.Filtration blanks need to be reported to maintain comparability between methods.Cool and frozen storage of water samples biases the dissolved metal concentration. [ABSTRACT FROM AUTHOR]

A method for determining the platinum‐group elements (PGEs) and rhenium (Re) in archaeological bronzes was developed. For 20 mg of sample, detection limits of 0.07 (Re) to 1.4 (palladium; Pd) ng g–1 were achieved. The method was tested on standards and compared with measurements determined by the PGEs via matrix separation. The method was applied to 45 samples from the Bronze Age to the Middle Ages. In the process, the PGEs provided no further information for the Bronze Age samples. The samples from the Hallstatt and La Tène Period show increased contents of Pd and platinum (Pt). These contents distinguished the samples from all other samples and give an important indication of the possible ores used. Three groups can be distinguished in the Middle Ages by their Pd and Pt contents. One group falls into the field of Bronze Age samples. The other two groups have significantly higher Pd and Pt contents. One group has higher Pd than Pt contents, while the other group has exactly the opposite. In a sample, it is possible that the high contents of Pd and other PGEs indicate the use of copper shale in the Eisenach area. [ABSTRACT FROM AUTHOR]

Background: Patients receiving long-term parenteral nutrition (PN) treatment are at risk of developing metabolic bone diseases (MBDs). The bone compartment serves as a repository for a range of metal(loid)s that are administered intravenously to patients via PN solutions. Thus, the mineral composition of patient bones may be linked to the development of MBDs in this group.Methods: We measured 12 elements in bone samples obtained post mortem from 7 long-term (2-21 years) PN patients and 18 control bones obtained from hip/knee replacement surgery. The samples were cleaned, digested, and subsequently analyzed using a method based on inductively coupled plasma tandem mass spectrometry.Results: Compared with the control group, bones obtained from PN patients were significantly (P < 0.05) depleted in calcium (Ca), phosphorus (P), magnesium (Mg), chromium, and strontium and enriched in manganese (Mn), zinc, barium, cadmium (Cd), and uranium (U). No differences were observed for cobalt or lead.Conclusions: Depletion of major components of bone mineral (Ca, P, and Mg) and enrichment in known toxicants (Cd, Mn, U) are concerns for PN patients. [ABSTRACT FROM AUTHOR]

Die Verbrennung schwefelhaltiger Treibstoffe führt zu Umweltproblemen. Deshalb gelten strenge Bestimmungen, die den Schwefelgehalt von Treibstoffen auf wenige ppm begrenzen. Angesichts der Verringerung schwefelarmer Erdölquellen werden immer größere technische Anstrengungen nötig, diese Bestimmungen einzuhalten. Die Entschwefelung ist ein kritischer Teil im Rahmen des Raffinierungsprozesses, welcher jedoch nicht vollständig verläuft und der angesichts der Komplexität der vielen verschiedenen Stoffklassen auch nicht völlig verstanden ist. Wir stellen hier einen neuen Ansatz vor, um drei Klassen von Schwefelverbindungen in Erdöl mithilfe einer LC ‐ Trennung und Detektion per ICP ‐ MS/MS zu quantifizieren. Diese neue, einfache Methode sollte helfen, den Anteil schwer entschwefelbarer Verbindungen abzuschätzen und so den Entschwefelungsprozess zu optimieren. Schwefel in Öl: Die Entschwefelung von Erdöl ist die vermutlich meistgenutzte katalytische Reaktion in der Industrie. Die Optimierung der Reaktion basiert allerdings nicht auf molekularen Informationen, sondern auf Bulk ‐ Parametern, die keinerlei Strukturinformationen beinhalten. Hier wird eine quantitative und qualitative Analyse vorgestellt, die es mit detaillierten Informationen erlaubt, derart wichtige Prozesse auf Basis molekularer Informationen zu optimieren. [ABSTRACT FROM AUTHOR]

Owing to the environmental hazards arising from sulfur-containing combustion products, strong legal regulations exist to reduce the sulfur content of transportation fuels down to a few ppm. With the ongoing depletion of low-sulfur crude oil reservoirs, increased technological efforts are needed for crude oil refining to meet these requirements. The desulfurization step is a critical part of the refining process but partly suffers from the recalcitrance of certain species to sulfur removal and the inability to quantitatively understand the behavior of individual compound classes during the process. We herein present a new and simple approach for the parallel quantification of three different classes of sulfur species present in crude oils by LC separation and on-line detection and quantification by ICP-MS/MS. This approach will help to estimate the amount of recalcitrant species and thus facilitate the optimization of desulfurization conditions during fuel production. [ABSTRACT FROM AUTHOR]