Investigating sources and sinks of N2O expression from freshwater microbial communities in urban watershed sediments

Wastewater treatment plants (WWTPs) serve as point-source inputs for a variety of nutrients often dominated by nitrogenous compounds as a result of anthropogenic influence. These effluents can impact biogeochemical cycles in freshwater estuaries, influencing microbial communities in both the water and sediment compartments. To assess the impact of point source nutrients, a transect of sediment and pore water samples were collected from 4 locations in the Little River Sub-watershed including locations above and below the Little River Pollution Control Plant (LRPCP). Variation in chemistry and microbial community/gene expression revealed significant influences of the effluent discharge on the adjacent sediments. Phosphorus and sulfur showed high concentrations within plume sediments compared to the reference sediments while nitrate concentrations were low. Increased abundance of denitrifiers Dechloromonas, Dok59 and Thermomonas correlating with increased expression of nitrous-oxide reductase suggests a conversion of N2O to N2 within the LRPCP effluent sediments. This study provides valuable insight into the gene regulation of microbes involved in N metabolism (denitrification, nitrification, and nitrite reduction to ammonia) within the sediment compartment influenced by wastewater effluent. © 2017 Elsevier Lt

Mikrobearbeitung mit dem Funkenerosionsverfahren am Beispiel einer Zahnradpumpe

Miniaturisierte Verdrängerpumpen sind eine neue Alternative in der Mikrohydraulik. Zu den geeigneten Herstellverfahren gehört die Funkenerosion

Vorrichtung zur Signaluebertragung

A device for signal transmission for application in industrial robots with at least two transmission modules intercommunicating over a transmission link is characterized by the transmission modules being linked by an addressable input module and by an addressable output module. Each of the transmission modules has a control logic which communicates with a transmit section and a receive section. The control logic controls the data transfer using time-division multiplexing with address generation. The input module and the output module are each linked over a parallel bus to one of the transmission modules

Umgang mit atomar kleinen Strukturen. Mikrosysteme erfordern eine Revolution der Produktionstechnik

Mikrosystemtechnik gilt als die Schlüsseltechnologie der Zukunft. Sie wird die nächste Revolution der industriellen Produktion auslösen. Noch sind nur wenige Mikrosysteme entwickelt, denn die Möglichkeiten dieser neuen Technologie sind bisher kaum vorstellbar. Der Montage und Handhabung in der Mikrosystemtechnik galt eine Expertenbefragung des Fraunhofer-Instituts für Produktionstechnik und Automatisierung (IPA), Stuttgart, im ersten Quartal 1993. Interviewt wurden 56 Firmen und Institute. Davon waren 60 Prozent Produktentwickler und -hersteller, 30 Prozent Systemlieferanten und 10 Prozent Institute

Organisationsstruktur ist wichtig. Montage kleiner und mittlerer Losgrössen

Um die Wettbewerbsfähigkeit in der Montage zu erhalten, ist eine organisatorische Umorientierung notwendig, mit dem Ziel, die Effizienz aller Arbeitsschritte zu steigern. Zudem ist der Qualitätsaspekt stärker in den Produktionsprozess einzubeziehen. Für die automatisierte Fertigung und Montage sind flexible Technologien zu entwickeln

Physicochemical gradients, diffusive flux, and sediment oxygen demand within oil sands tailings materials from Alberta, Canada

The Athabasca Oil Sands contain one of the world\u27s largest oil reserves consisting of approximately 168 billion barrels of currently recoverable bitumen. With 20% recoverable through open pit mining methods, this extraction process produces a considerable amount of fluid fine tailings (FFT) waste material, which must be deposited on site in tailings ponds. These ponds allow the waste sand, clay and residual bitumen to settle out of the water column, allowing for the water to be recycled for use again in the extraction process. It is vital to gain a better understanding of the processes contributing to the development of physicochemical gradients (pH, Eh, Oxygen etc…) that form in these tailings ponds over time, with the goal of remediation and subsequent construction of end-pit lake systems once oil extraction has ceased. To differentiate between the impacts of biotic and abiotic processes in fresh (newly processed material) and mature FFT (∼38 year old tailings) over a 52-week study, a specific experimental design was utilized in accordance with novel microsensor profiling techniques. The sulfide diffusive fluxes within mature biotic systems measured 37.6 μmol m−2 day−1 at the onset of the experiment, decreasing over time, as FeS mineralization progressed. In addition, DO fluxes also showed strong correlation to the physical affects of consolidation, and overall biological consumption of O2 at the FFT-water interface. This holistic study comparing different tailings pond materials provides insight regarding biotransformation and physicochemical controls effecting sediment oxygen demand associated with reclaimed wetlands and end pit lake development

Mikroskopische Visionen für Montage und Greiftechnik

Montage und Handhabungstechnik gewinnen in der Produktion von Mikro-Systemen eine immer größere Bedeutung, wie die am IPA durchgeführten Marktstudie zeigt. Neue Greifsysteme wie der Adhäsionsgreifer ermöglichen ein Vordringen in kleinste Dimmensionen von Bauelementen