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    The Influence of Processing Parameters on the Mitigation of Deoxynivalenol during Industrial Baking

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    Deoxynivalenol (DON), a frequent contaminant of flour, can be partially degraded by baking. It is not clear: (i) How the choice of processing parameter (i.e., ingredients, leavening, and baking conditions) affects DON degradation and thus (ii) how much DON can be degraded during the large-scale industrial production of bakery products. Crackers, biscuits, and bread were produced from naturally contaminated flour using different processing conditions. DON degradation during baking was quantified with the most accurate analytical methodology available for this Fusarium toxin, which is based on liquid chromatography tandem mass spectrometry. Depending on the processing conditions, 021%, 416%, and 25% DON were degraded during the production of crackers, biscuits, and bread, respectively. A higher NaHCO3 concentration, baking time, and baking temperature caused higher DON degradation. NH4HCO3, yeast, vinegar, and sucrose concentration as well as leavening time did not enhance DON degradation. In vitro cell viability assays confirmed that the major degradation product isoDON is considerably less toxic than DON. This proves for the first time that large-scale industrial baking results in partial detoxification of DON, which can be enhanced by process management.(VLID)365712

    Residual-state creep of clastic soil in a reactivated slow-moving landslide in the Three Gorges Reservoir Region, China

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    We study the creep properties of clastic soil in residual state. The intact samples are taken from a reactivated slow-moving landslide in the Three Gorges Reservoir Region, China. Firstly, the patterns of the landslide movement are analysed based on recent monitoring data, which indicate that the soil within the shear zone is undergoing two deformation processes: a creep phase, characterized by different creep rates, and a dormant phase. We then study the creep behaviour of the soil samples through a series of ring shear creep tests under various shear stress conditions. The creep response depends strongly on the ratio of the shear stress to the residual strength, and the normal effective stress, whereas the creep rate decreases due to strength regain. The long-term strength of the clastic soil is close to the residual strength. Therefore, the residual strength obtained from conventional shear test, which is less time consuming than creep test, can be used in long-term stability analyses of creeping landslides.645665 GEO-RAMPNSFC No. 41502280 and 41772304(VLID)367572

    Numerical integration and FE implementation of a hypoplastic constitutive model

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    Hypoplastic constitutive equation based on nonlinear tensor functions possesses a failure surface but no yield surface. In this paper, we consider the numerical integration and FE implementation of a simple hypoplastic constitutive equation. The accuracy of several integration methods, including implicit and explicit methods, is examined by performing a set of triaxial compression tests. Adaptive explicit schemes show the best performance. In addition, the stress drift away from the failure surface is corrected with a predictor-corrector scheme, which is verified by two boundary value problems, i.e. rigid footing tests and slope stability.645665 GEO-RAMPNSFC 41772304(VLID)367573

    Feasibility of Locating Leakages in Sewage Pressure Pipes Using the Distributed Temperature Sensing Technology

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    Nicht verfügbarThe cost effective maintenance of underwater pressure pipes for sewage disposal in Austria requires the detection and localization of leakages. Extrusion of wastewater in lakes can heavily influence the water and bathing quality of surrounding waters. The Distributed Temperature Sensing (DTS) technology is a widely used technique for oil and gas pipeline leakage detection. While in pipeline leakage detection, fiber optic cables are installed permanently at the outside or within the protective sheathing of the pipe; this paper aims at testing the feasibility of detecting leakages with temporary introduced fiber optic cable inside the pipe. The detection and localization were tested in a laboratory experiment. The intrusion of water from leakages into the pipe, producing a local temperature drop, served as indicator for leakages. Measurements were taken under varying measurement conditions, including the number of leakages as well as the positioning of the fiber optic cable. Experiments showed that leakages could be detected accurately with the proposed methodology, when measuring resolution, temperature gradient and measurement time were properly selected. Despite the successful application of DTS for leakage detection in this lab environment, challenges in real system applications may arise from temperature gradients within the pipe system over longer distances and the placement of the cable into the real pipe system.(VLID)214131

    A cautionary note on thermal runaway reactions in mixtures of 1-alkyl-3-methylimidazolium ionic liquids and N-methylmorpholine-N-oxide

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    Nicht verfügbarN-Methylmorpholine-N-oxide (NMMO) cannot be completely separated by extraction from mixtures with common 1,3-dialkylimidazolium ionic liquids (ILs) due to strong ionic interactions between the two components. At elevated temperatures, above approx. 90 C, especially under dry conditions and in the presence of acid, alkylating or acylating agents, remaining NMMO in ILs tends to undergo autocatalytic degradation. This is a highly exothermic, unstoppable process that results in explosions, flames, and complete charring of the reaction mixtures. Thus, caution must be exercised when drying or heating ILs that were in previous contact with NMMO, and the absence of amine oxide must be confirmed to avoid potential danger.(VLID)192930

    Heatprecipitation of homogenates : scale-up study

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    In dieser Arbeit wurde die Wärmeübertragung in einem Rührkesselreaktor mit Doppelmantel auf Basis von Wasser als Modellierfluid charakterisiert. Es wurden die thermischen Widerstände der thermischen Grenzschichten auf der Doppelmantel- und Tankseite bestimmt. Diese Widerstände wurden mit publizierten Korrelationen berechnet und zur Berechnung einer theoretischen Wärmedurchgangszahl verwendet. Die Wärmedurchgangszahl wurde auch durch praktische Experimente ermittelt. Die theoretische Berechnung ergab eine Wärmedurchgangszahl von 370,0 W/m2K für den Heizprozess und 283,6 W/m2K für den Kühlprozess. Die praktisch ermittelte Wärmedurchgangsz. war 445,7 W/m2K für den Heizprozess und 326,2 W/m2K für den Kühlprozess. Die ermittelten Wärmedurchgangszahlen wurden für die Modellierung eines Hitzefällungsschritts einer rekombinanten Proteinlösung verwendet. Das berechnete Temperaturprofil wurde mit der Hitzepräzipitation einer Green Fluorescent Protein enthaltenden Homogenats verglichen. Die Stabilität des Green Fluorescent Proteins gegenüber der Hitzebehandlung wurde im kleinen, sowie im großen Maßstab untersucht. Die Hitzepräzipitation wurde zuerst im kleinen Maßstab durchgeführt und dann auf 50 kg Homogenat vergrößert. Um das optimale Ausgangsmaterial zu erhalten, wurde der Homogenisationsschritt hinsichtlich Aufschlussgrad, Viskosität und Größe der Zellbruchstücke untersucht. Auch die auf die Hitzepräzipitation folgenden Aufarbeitungsschritte wurden untersucht. Dazu zählten die Abtrennung des Präzipitats, Tiefen- und Sterilfiltration des Überstands im kleinen und großen Maßstab, Ultra- und Diafiltration und Chromatographie (Capture Schritt mit Anionentauscher) Es konnte gezeigt werden, dass der Hitzepräzipitationsschritt den Aufarbeitungsprozess signifikant verbesserte. Die Abtrennung des Hitzepräzipitats war effizienter. Dadurch wurde für die folgende Sterilfiltration eine geringere Filterfläche benötigt. Die Kapazität des Anionentauschergels CaptoQ war signifikant höherIn this work the process of heat transfer in a stirred tank reactor equipped with a jacket was characterized on a basis of water as modelling fluid. Heat transfer was split up into the different resistances of the thermal boundary layers on the jacket and the vessel side. These individual resistances were calculated by published correlations to obtain the theoretical overall heat transfer coefficient. Moreover an overall heat transfer coefficient was determined in practical experiments. Theoretical calculation yielded an overall heat transfer coefficient of 370.0 W/m2K for heating and 283.6 W/m2K for cooling. Practical determination yielded an overall heat transfer coefficient of 445.7 W/m2K for heating and 326.2 W/m2K for cooling. The determined overall heat transfer coefficient was then used to model the heat precipitation process of a recombinant protein solution. The temperature profile prediction was compared to the actual heat precipitation of green fluorescent protein containing homogenate and the stability of green fluorescent protein to the heat treatment was assessed in small and large scale experiments. Heat precipitation was investigated in small scale and was then scaled up to 50 kg homogenate. In order to provide the best material for heat precipitation, homogenization was investigated in detail with respect to release of green fluorescent protein, viscosity and cell debris particle size. Also the downstream steps after heat precipitation were investigated. These include separation of precipitate, depth and sterile filtration of supernatant in small scale and scale up, ultrafiltration and diafiltration, chromatography capture step (anionic exchange chromatography). It could be shown, that the heat precipitation significantly improved the process. The separation of heat precipitate was shown to be more efficient. The obtained supernatant required less filter area for sterile filtration. The capacity on the anion exchanger CaptoQ was significantly higherverfasst von Christopher ZartlerUniversität für Bodenkultur Wien, Masterarbeit, 2017(VLID)193607

    Participatory Guarantee Systems in Spain : a case study of three PGS initiatives

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    Die zunehmende Anzahl von Bio-Bauern und Bio-Konsumenten erfordert eine Garantie für die biologische Erzeugung der Produkte. Die Zertifizierung ist ein Instrument, um das Informationsdefizit zwischen Konsumenten und Produzenten über Produktmerkmale zu überbrücken und zu bestätigen, dass ein Produkt mit bestimmten Standards übereinstimmt. Die Eignung dieser Zertifizierung für Kleinbauern wurde allerdings kritisiert und alternative Zertifizierungssysteme entwickelt, wie z.B. Partizipative Garantiesysteme (PGS). PGS sind Qualitätssicherungssysteme, in denen Stakeholder bei der Sicherung von Qualitätsansprüchen beteiligt sind. Diese Masterarbeit untersucht drei PGS-Initiativen in Spanien. Die angewandten Forschungsmethoden sind halbstrukturierte Interviews mit sechs Hauptakteuren, die an PGS in Spanien beteiligt sind und die dazu beitragen, den Status quo von PGS im Land zu beurteilen. 29 Mitglieder wurden mit einem strukturierten Interview mit offenen Fragen interviewt. Ziel war es, Struktur, Funktionalität und Herausforderungen dieser PGS-Initiativen zu beschreiben. Die untersuchten PGS-Initiativen haben je nach den lokalen Bedürfnissen unterschiedliche Strukturen. Die Regelungen der untersuchten PGS-Initiativen basieren auf der EU-Verordnung für Ökologische Landwirtschaft (EG) 889/2008, umfassen aber auch sozioökonomische Kriterien und IFOAM-Grundsätze. Interviewpartner erwähnen die Beteiligung der Stakeholder und die Effizienz der internen Organisation als zentrale Herausforderungen. Die fehlende offizielle Anerkennung von PGS in Spanien und die unzureichende Verbreitung von PGS werden auch als Herausforderung gesehen. Interviewte Produzenten betrachten die Gemeinschaft in ihren PGS-Initiativen und den Mehrwert für ihre Produkte durch PGS als wichtige Motivationen. Obwohl PGS das Potenzial für Entwicklung in Spanien hat, braucht es noch Unterstützung und offizielle Anerkennung.The increasing number of organic producersas as well as consumer causes the need to guarantee the organic characteristics of products. Certification is a tool to bridge the information deficit between demand and supply about product characteristics, conforming that a product is in conformity with specified standards. Today, third party certification (TPC) is the prominent impartial conformity assessment tool for organic products. However, the suitability of TPC for small scale farmers has been criticized and alternative certification systems were developed, like e.g. Participatory Guarantee Systems (PGS). PGS are quality assurance systems, in which various stakeholders are involved for ensuring quality claims made by producers. PGS initiatives have been developed worldwide, incl. in Spain. This master thesis studies three PGS initiatives in Valencia, Murcia and Granada (Spain). The research methods applied are semi-structured interviews with 6 key actors involved in PGS in Spain, which contribute to assess the status quo of PGS in the country. 29 members were interviewed with a structured interview with open questions. Aim was describing structure, functionality and challenges of these PGS initiatives. The studied PGS initiatives have different structures, depending on their local needs. The internal regulations of the studied PGS initiatives are based on the EU Organic Farming Regulation (EC) 889/2008, but also include socio-economic criteria and IFOAM principles. Interviewees mention participation of stakeholders and efficiency of internal organization as main challenges. The missing official recognition of PGS in Spain and insufficient dissemination of PGS are also seen as challenge. Interviewed producers perceive the community built in their PGS initiatives and the added value to products given by PGS as important motivations. Although PGS has the potential for developing in Spain, it still needs more support and official recognition.Marta López CifuentesZusammenfassung in deutscher SpracheUniversität für Bodenkultur Wien, Masterarbeit, 2017(VLID)193598

    A study of exotic macrophytes for the phytoremediation of flooded agricultural land polluted with cadmium

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    In der Arbeit wurde die Einsatzmöglichkeit von Egeria densa und Cabomba caroliniana zur aquatischen Phytoremediation von Kadmium erforscht. Die Pflanzen wuchsen für 34 Tage in aquatischen Mikrosystemen, bestehend aus einer 1,5 L PET Flasche, 200 g Kadmium-verseuchtem Boden, einer Pflanze und 1,1 L Leitungswasser. Der Boden wurde mit Kadmiumlösungen verschmutzt um Konzentrationen von 0, 3, 15, 25 und 50 g Kadmium (Cd) pro Gramm Boden (g/g) zu erreichen. Nach der Ernte wurden die Wurzeln- und Sprossbiomassen gewogen. Die Wurzel wurden zudem gescannt um die Wurzelmorphologie zu erhalten. Die Cd Konzentrationen im Boden und im Wasser wurden mit einer ICP-OES gemessen. Die Bodenbeschaffenheit und Kadmiumkonzentrationen im Boden hatten den stärksten Einfluss auf die Kadmiumkonzentrationen in den Pflanzen. Egeria densa zeigte Phytotoxizitätssymptome und sie nahm mehr Cd auf aber sie gab auch mehr Cd in das Wasser ab. Im Gegensatz zeigte Cabomba caroliniana keine Symptome von Phytotoxizität, nahm jedoch auch weniger Cd auf. Nach den Ergebnissen dieser Fallstudie ist keine der beiden getesteten Pflanzenarten besonders gut für die Cd Phytoremediation in aquatischen Ökosystemen geeignet.Cadmium (Cd) is a heavy metal that is extremely toxic for humans and the environment. Cd is released into the environment through industrial use, fertilizers, mining and waste incineration among others. Once Cd reaches the environment it accumulates in the soil and in the sediments of aquatic ecosystems, where it enters the food chain and it is biomagnified as it moves through the trophic levels. The possible use of Egeria densa and Cabomba caroliniana as cadmium phytoremediation species was investigated. The plants grew 34 days in microsystems composed of a 1.5 L PET bottle with 200g of polluted soil, one plant and 1.1 L of unpolluted tap water. The soil was polluted with cadmium to concentrations of 0, 3, 15, 25 and 50 g of Cd per gram of soil (g/g). After the harvest the root and plant weight were recorded; the roots were scanned to obtain root morphology information. The Cd concentrations in the water and in the plants were measured using ICP. The soil properties and cadmium concentration in the soil had the biggest effect on the Cd concentration in the plant. Egeria densa showed symptoms of phytotoxicity and adsorbed more Cd but it also leached more Cd into the water. While Cabomba caroliniana did not show symptoms of phytotoxicity it adsorbed less Cd and it leached minor amounts into the water. To the extent of this research neither of species showed signs of being particularly useful to be used as Cd phytoremediator in sediments of aquatic ecosystems.submitted by Rodrigo Valencia CoteraZusammenfassung in deutscher SpracheUniversität für Bodenkultur Wien, Masterarbeit, 2017(VLID)193563

    Über die Gebrauchsfähigkeit der Freiräume für Kinder und Jungendliche in der Gemeinde Mannsdorf an der Donau

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    Die vorliegende Masterarbeit behandelt das Thema der Freiraumqualitäten für Kinder und Jugendliche am Beispiel der Gemeinde Mannsdorf an der Donau. Dabei wird verstärkt die Gebrauchsfähigkeit der vorhandenen Freiräume erforscht und diskutiert. Die Grundlage der Masterarbeit bilden Recherchen zur Theorie der Landschafts- und Freiraumplanung, aber auch zur Entwicklungstheorie des Menschen. Das Methodenset vereint die literarische Recherche, freiraumplanerische Erhebungen und dazugehörige Interpretationen, um daraus eine Realnutzungskartierung zu erstellen, mit der die aktuelle Freiraumsituation im Beispielort ersichtlich wird. Aus dieser freiraumplanerischen Bewertung werden Prinzipien für die Organisation und Gestaltung von kinder- und jugendfreundlichen Freiräumen abgeleitet. Weiters soll durch Vergleiche der Planungsinstrumente der Gemeinde versucht werden, die Dorfstrategie herzuleiten, um in weiterer Folge über die Gebrauchsqualitäten der vorhandenen Freiräume diskutieren zu können. Im Fokus sollen stets die Kinder und Jugendlichen sein, denn diese sind die Zukunft des Dorfes. Ein zentrales Ergebnis dieser Arbeit ist, dass Freiräume eine hohe Nutzungsvielfalt und Vernetzung aufweisen sollen. Dies bedeutet jedoch nicht, dass zur Ausstattung solcher nur überteuerte Geräte etc. gehören. Oft reicht es aus, eine Nutzung durch Kinder und Jugendliche zuzulassen, denn diese eignen sich Freiräume gerne selbst an und benötigen dazu oftmals nicht viel. Dies zeigen vor allem dysfunktionale Freiräume, denn auf diesen halten sich laut Studien Kinder und Jugendliche zeitlich gesehen länger auf, als in funktionalen Freiräumen. Diese Tatsache entspricht ganz dem Motto „weniger ist oft mehr“, was vor allem in der heutigen Zeit, in der stets neue Technologien zur Verfügung stehen und auf den Markt gebracht werden, eine Herausforderung für die PlanerInnen ist.This paper deals with the topic of the qualities of open spaces regarding children and teenagers by the example of the village Mannsdorf an der Donau. The focus of discussion will be put on the usability of the open spaces that are available. The basis of this paper is research regarding landscape and open space planning theory, but also an analysis of the theory of human development. The set of methods unites the research of literature, open-space-planning-stocktaking and its interpretation in order to be able to create a mapping of existing land uses so that the present situation in the representative village can be understood. After the open space evaluation principals for the organisation and design of open spaces meant for children and teenagers will be deducted. Furthermore, by comparing local planning instruments it will be tried to derive a planning strategy of the village to be able to discuss the qualities and usability of the open spaces available. The focus will be firmly put on children and teenagers as they are the future of the village. A central result of this paper was that open spaces should offer a high variety and better networking for use. This does not mean, however, that equipment for a playground always need to be expensive. Most of the time it is more important to allow children and young people to make use of these spaces as they like to adopt them themselves and for that purpose not much is needed. This is especially true for dysfunctional open spaces as according to research children and teenagers like to spend more time there than in functional open spaces. This shows that the saying "less is more" is really true, especially regarding the fact that in today's world new technologies are readily available on the market and this poses special challenges for planners.Verfasserin: Daniela Pollaschak"Jugendliche" ist im Titel falsch geschriebenMit englischer ZusammenfassungUniversität für Bodenkultur Wien, Masterarbeit, 2017(VLID)193561

    Chromophores from hexeneuronic acids (HexA): synthesis of model compounds and primary degradation intermediates

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    Hexeneuronic acid (HexA) is formed under pulping conditions from 4-O-methyl-glucuronic acid residues in xylans by methanol elimination. It is usually removed by an acidic washing treatment (A-stage) within the pulp bleaching sequence. Hexeneuronic acid has long been recognized as a source of color generation in pulps, but the chemical structure of the actual chromophoric compounds remained elusive. We report the synthesis of isotopically (13C) labeled HexA model units carrying a label at any of the six carbon atoms. Confirming pertinent literature accounts, it is shown that HexA forms three primary degradation intermediates, 2-furancarboxylic acid, 5-formyl-2-furancarboxylic acid, and formic acid, under mildly acidic conditions, and their formation mechanism is discussed. 2-Furancarboxylic acid is demonstrated to be deformylation product of 5-formyl-2-furancarboxylic acid. The three primary intermediates are colorless and do not represent chromophores themselves. Their mixture, upon thermal or acidic treatment, gives rise to the same chromophores that are also directly formed from HexA.(VLID)221167

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