1,720,965 research outputs found
Charakterisierung eines organischen Scalinginhibitors und dessen Abbauprodukte mit Hilfe verschiedener Analyseverfahren
Get PDFÖkologisch unbedenkliche, abbaubare Scaling-Inhibitoren sind für die Anwendung in der tiefen Geothermie erforderlich, um die Wirtschaftlichkeit der Anlagen zu verbessern und eine Genehmigung für die Einleitung der Inhibitoren in den Untergrund zu erhalten. Im Forschungsvorhaben EvA-M werden erstmalig Inhibitoren zur Vermeidung bzw. Verminderung von Ausfällungen in Geothermieanlagen des Bayerischen Molassebeckens eingesetzt. Die Inhibitorzugabe erfolgt in enger Zusammenarbeit von Betreibern, Industrie und wird wissenschaftlich evaluiert.
In einigen Geothermieanlagen ist in Folge der Ausfällung von Carbonaten derzeit kein geregelter Betrieb zur Förderung von Thermalwasser mit Temperaturen von > 100 °C und Fördervolumina > 100 L/s möglich. Zur Vermeidung solcher Ausfällungen soll nun der Inhibitor NC47.1B im Rahmen eines Langzeitversuches unterhalb der Tauchkreiselpumpe injiziert werden. Hierbei sollen wertvolle Informationen a) zur Wirksamkeit des Inhibitors im Anlagenmaßstab, b) zum Abbau des Inhibitors im Untergrund, c) zur Verbreitung des Inhibitors im Untergrund, d) zur Wechselwirkung des Inhibitors mit den Gesteinen des Reservoirs sowie e) zum mikrobiellen Abbau und dem Einfluss auf die Biozönose beim Einsatz des Inhibitors gewonnen werden. Diese Erkenntnisse sind wichtig, um die Folgen eines Langzeiteinsatzes von Inhibitoren sowohl für die Anlagen als auch für das hydrogeologische Fließsystem des Malmaquifers zu bewerten. Um diese Ziele zu erreichen, sind Versuche in unterschiedlichen Maßstäben und an verschiedenen Bypass- und Testsystemen
sowie ein umfängliches technisches, hydrochemisches und mikrobiologisches
Monitoring notwendig. Die Inhibitoren werden sowohl in synthetischen als auch in natürlichen geother¬mischen Fluiden getestet und für standortspezifische Thermalwässer und unterschiedliche Temperaturen erprobt
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Optimization of the precision and accuracy of methods for the determination of chloroprene rubber (CR) in complex elastomer blends and technical elastomeric materials
No full textThe Instrumental Analysis and Polymer Characterization group (IAPC) in Merseburg is specialized in the characterization of physical and chemical properties of polymers. Technical elastomers are characterized by the polymer composition and the additives used. For chloroprene rubber (CR), it is difficult to determine quantitatively the polymer-related CR content by pyrolysis GC/MS due to its inaccurate and time-consuming nature. The goal of this thesis is to combine the Schöniger digestion (SD) with Thermo gravimetric analysis (TGA) in order to determine the CR content in an elastomeric mixture.
The SD is an oxidation method used for determining the presence of chloride. The SD had to be optimized in order to accelerate the method and realise high yields of chloride. The second method, TGA, was used for the determination of the rubber amount in an elastomeric mixture. TGA was executed on pure samples and elastomeric mixtures to determine the decay steps for each material. A mathematical formula was calculated for binary and ternary elastomeric mixtures.
The results were successful. The Schöniger digestion was accelerated 2.4 times and a high yield of chloride was realized. The calculated formula from the TGA measurements had an overshoot but the results show that there is correlation between the measured and calculated values. After comparison with Pyrolysis GC/MS, results concluded that it is possible to use the combined method for an accurate CR determination
Entwicklung einer Methode zur kontinuierlichen Erfassung der Formaldehydemissionen in Biogasanlagen auf der Grundlage eines spektrometerbasierten Heißgasanalysators
Get PDFOptimization of the precision and accuracy of methods for the determination of chloroprene rubber (CR) in complex elastomer blends and technical elastomeric materials
No full textThe Instrumental Analysis and Polymer Characterization group (IAPC) in Merseburg is specialized in the characterization of physical and chemical properties of polymers. Technical elastomers are characterized by the polymer composition and the additives used. For chloroprene rubber (CR), it is difficult to determine quantitatively the polymer-related CR content by pyrolysis GC/MS due to its inaccurate and time-consuming nature. The goal of this thesis is to combine the Schöniger digestion (SD) with Thermo gravimetric analysis (TGA) in order to determine the CR content in an elastomeric mixture.
The SD is an oxidation method used for determining the presence of chloride. The SD had to be optimized in order to accelerate the method and realise high yields of chloride. The second method, TGA, was used for the determination of the rubber amount in an elastomeric mixture. TGA was executed on pure samples and elastomeric mixtures to determine the decay steps for each material. A mathematical formula was calculated for binary and ternary elastomeric mixtures.
The results were successful. The Schöniger digestion was accelerated 2.4 times and a high yield of chloride was realized. The calculated formula from the TGA measurements had an overshoot but the results show that there is correlation between the measured and calculated values. After comparison with Pyrolysis GC/MS, results concluded that it is possible to use the combined method for an accurate CR determination
Einfluss des Benetzungsverhaltens auf die Verbindungsqualität und die Kontakteigenschaften typischer Lötwerkstoffe für die Solarverschaltung
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