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Sample records for biofilter modellierung und

  1. Haptische Modellierung und Deformation einer Kugelzelle

    Science.gov (United States)

    Schippritt, Darius; Wiemann, Martin; Lipinski, Hans-Gerd

    Haptische Simulationsmodelle dienen in der Medizin in erster Linie dem Training operativer Eingriffe. Sie basieren zumeist auf physikalischen Gewebemodellen, welche eine sehr genaue Simulation der biomechanischen Eigenschaften des betreffenden Gewebes erlauben, aber gleichzeitig sehr rechenintensiv und damit zeitaufwändig in der Ausführung sind. Die menschliche Wahrnehmung kann allerdings auch eine ungenaue haptische Modellierung psychooptisch ausgleichen. Daher kann es sinnvoll sein, haptische Simulationen auch mit nicht vollständig physikalisch definierten Deformationsmodellen durchzuführen. Am Beispiel der haptischer Simulation einer in-vitro Fertilisation wird gezeigt, dass durch die Anwendung eines geometrischen Deformationsmodells eine künstliche Befruchtung unter realistischen experimentellen Bedingungen in Echtzeit haptisch simuliert und damit trainiert werden kann.

  2. Environment and health in perspective of system theory. Part II; Umwelt und Gesundheit aus systemwissenschaftlicher Perspektive. Teil II. Systemische Modellierung

    Energy Technology Data Exchange (ETDEWEB)

    Tretter, F. [Bezirkskrankenhaus Haar, Haar (Germany); Heiden, U. an der [Inst. fuer Mathematik und Theorie komplexer Systeme, Univ. Witten-Herdecke, Witten (Germany)

    2004-07-01

    The development of descriptive and explanatory models of complex system like ecosystems requires a certain methodological procedure which has been generated during the last 30 years. Essentially it is related to mathematical modeling thought it is not only the application of mathematical approaches and tools. Also aspects of philosophy of science and epistemology with regard to 'reality' and 'truth' must be taken into account. Only in a constructive perspective it is acceptable that also 'soft' data are used for modeling. System models in this way are strategies for generating hypotheses. In this paper it is attempted to present this issue by using simple models. (orig.) [German] Die Entwicklung von Beschreibungs- und Erklaerungsmodellen komplexer realer Systeme, wie es beispielsweise Oekosysteme sind, erfordert ein bestimmtes methodisches Vorgehen, das in den letzten 30 Jahren aufgebaut wurde. Im Wesentlichen handelt es sich um die mathematisch-systemische Modellierung. Dabei muss beachtet werden, dass es sich nicht nur um die Anwendung bestimmter mathematischer Ansaetze und Techniken handelt, sondern dass auch wissenschaftstheoretische und erkenntnistheoretische Aspekte zum Thema 'Wirklichkeit' und 'Wahrheit' mitbedacht werden muessen. Nur unter einer konstruktivistischen Perspektive ist es ohne weiteres akzeptabel, auch 'weiche' Daten zur Modellierung zu nutzen. Systemmodelle sind daher eine Strategie zur Hypothesengenerierung. Anhand von einfachen Modellen wird versucht, diesen Bereich in Grundzuegen darzustellen. (orig.)

  3. Mathematical modelling and laser measurement technique of combustion processes. Final report 1994-1996; Mathematische Modellierung und Lasermesstechnik von Verbrennungsvorgaengen. Abschlussbericht 1994 - 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    Due to financial boundary conditions and greater industrially orientated targets, the project was restructured in its third phase. The general theme `Mathematical modelling and laser measurement technique of combustion processes` was made more precise by the central questions of the Sub-heading `Modelling and validation`. It applies equally as target for the three part projects (a) Modelling process, (b) Standard flames (c) Coal and solid combustion, soot formation, radiation. Due to the preliminary work done, good progress was achieved in all projects, in some cases discoveries were made and new types of projects were developed. The quality and quantity of the basic data as input parameters for modelling and validation data as test parameters for the prediction of the models was expanded further by comparison of different methods of measurement. [Deutsch] Aufgrund der finanziellen Randbedingungen und der staerker industrieorientierten Zielsetzungen wurde das Projekt in seiner dritten Phase neu strukturiert. Das Generalthema `Mathematische Modellierung und Lasermesstechnik von Verbrennungsvorgaengen` wurde um die zentralen Fragestellungen als Zwischenueberschrift praezisiert: `Modellierung und Validierung`. Sie gilt fuer die drei Teilprojekt (a) Modellierungsverfahren (b) Standardflammen (c) Kohle- und Feststoffverbrennung, Russbildung, Strahlung in gleichem Mass als Zielsetzung. In allen Vorhaben konnten aufgrund der geleisteten Vorarbeit gute Fortschritte erzielt werden, in einigen Faellen Entdeckungen gemacht und neuartige Verfahren entwickelt werden. Die Qualitaet und Quantitaet der Basisdaten als Eingangsgroessen fuer die Modellierung und der Validierungsdaten als Testgroessen fuer die Voraussagen der Modelle konnten durch Vergleich unterschiedlicher Messmethoden generell weiter ausgebaut werden. (orig.)

  4. Air/ground heat exchanger (GHE): Modelling, design, performance; Luft-/Erdwaermetauscher EWT: Modellierung, Auslegung und Betriebserfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Gerber, A. [Fraunhofer-Inst. fuer Solare Energiesysteme, Freiburg (Germany); Pfafferott, J. [Energieversorgung Spree-Schwarze Elster AG (ESSAG), Cottbus (Germany); Dibowski, G. [Deutsches Zentrum fuer Luft- und Raumfahrt e.V. (DLR), Koeln (Germany). Abt. Sonnenofen

    1998-02-01

    Air/Ground Heat Exchanger (GHE) utilize soil for seasonal heat storage and are used for air preheating or -cooling. Design and layout require suitable tools which adequately describe the complex heat temperature mechanisms in soils. Since heat densities in soil and heat exchange coefficients between air and GHE are both low, a detailed characterization of the soil and a precise modeling of the heat exchange processes within the GHE are needed. Tools for the design and yield prediction of GHE are presented by way of examples. Results are compared with measured data and both opportunities and limitations of GHEs are discussed using calculated and actual data. (orig.) [Deutsch] Luft-/Erdwaermetauscher EWT nutzen das Erdreich als saisonalen Energiespeicher, sie werden beispielsweise zur Zuluft-Vorerwaermung oder -kuehlung eingesetzt. Die Planung und Auslegung von Luft-/Erdwaermetauschern erfordert geeignete Hilfsmittel, um das komplizierte Temperaturfeld im Erdreich mit ausreichender Genauigkeit abbilden zu koennen. Da die Waermestromdichten im Erdreich und der Waermeuebergang zwischen der Luft im Luft-/Erdwaermetauscher und dem umgebenden Erdreich gering sind, ist sowohl eine detaillierte Abbildung des Erdreichs als auch die Modellierung des Waermeuebergangs im Luft-/Erdwaermetauscher erforderlich. Verfahren zur Auslegung und Ertragsvorhersage von Luft-/Erdwaermetauschern werden vorgestellt und deren Anwendung demonstriert. Die Ergebnisse werden mit Betriebserfahrungen von realisierten Luft-/Erdwrmetauschern verglichen. Moeglichkeiten und Grenzen von Luft-/Erdwaermetauschern werden anhand von Praxis und Simulationsrechnungen diskutiert. (orig.)

  5. Optimisation of waste air purification in mechanical-biological waste treatment by combining RTO and biofilters; Optimierung der Abluftreinigung bei der MBA durch Kombination von RTO und Biofilter

    Energy Technology Data Exchange (ETDEWEB)

    Cuhls, C. [gewitra mbH Ingenieurgesellschaft fuer Wissenstransfer, Betriebsstaette Nord, Hannover (Germany)

    2004-07-01

    Both biofilters and RTO can be sources of climate-relevant gaseous emissions (NO2, NO) from conversion of NH3 and organic N. For this reason, an acid scrubber stage, e.g. a counterflow scrubber with filler bodies, should be connected in series if NH3 and organic N concentrations in raw gas are high. Both substances are alkaline and are absorbed in acid. In the case of sulphuric acid, ammonium sulfate solution is obtained which may be concentrated up and used in industrial processes or as fertilizer. (orig.) [German] Die Kenntnisse ueber Bildung und Minderung klimarelevanter Spurengase wie NO (Ozonzerstoerung) und N{sub 2}O (Ozonzerstoerung und Beteiligung am Treibhauseffekt) in Biofiltern und RTO sind noch unzureichend. Juengste Messungen an Pilot- oder Versuchsanlagen zeigen, dass sowohl Biofilter als auch RTO als Emittenten von Treibhausgasen (N{sub 2}O, NO) fungieren koennen. Dies resultiert vor allem aus Umsetzungen von NH{sub 3} und org.N. Aus diesem Grund sollte den Systemen eine saure Waesche z.B. in Form eines Gegenstromwaeschers mit Fuellkoerpern vorgeschaltet werden, wenn entsprechend hohe NH{sub 3} - und org.N - Konzentrationen im Rohgas vorliegen. NH{sub 3} und org.N reagieren basisch und werden in Saeure absorbiert. Bei Verwendung von Schwefelsaeure entsteht Ammoniumsulfatloesung, die ggf. nach Weiterbehandlung als Konzentrat industriell oder als Duenger verwertet werden kann. (orig.)

  6. Analytische Modellierung des Zeitverhaltens und der Verlustleistung von CMOS-Gattern

    Directory of Open Access Journals (Sweden)

    R. Geißler

    2003-01-01

    Full Text Available In modernen CMOS-Technologien werden die Verzögerungszeit, die Ausgangsflankensteilheit und der Querstrom eines Gatters sowohl durch die Lastkapazität als auch durch die Steilheit des Eingangssignals beeinflusst. Die heute verwendeten Technologiebibliotheken beinhalten Tabellenmodelle mit 25 oder mehr Stützpunkten dieser Abhängigkeiten, woraus durch Interpolation die benötigten Zwischenwerte berechnet werden. Bisherige Versuche, analytische Modelle abzuleiten beruhten darauf, den Querstrom zu vernachlässigen oder Transistorströme als stückweise linear anzunähern. Der hier gezeigte Ansatz beruht auf einer näherungsweisen Lösung der Differentialgleichung, die aus den beiden Transistorströmen und einer Lastkapazität besteht und damit das Schaltverhalten eines Inverters beschreibt. Mit wenigen Technologieparametern können daraus für einen beliebig dimensionierten Inverter die für eine Timing- und Verlustleistungsanalyse notwendigen Größen berechnet werden. Das Modell erreicht bei einem Vergleich zu Referenzwerten aus SPICE Simulationen eine Genauigkeit von typischerweise 5%.In modern CMOS-technologies the gate delay, output transition time and the short-circuit current depend on the capacitive load as well as on the input transition time. Today’s technology libraries use table models with 25 or more samples for these dependencies. Intermediate values have to be calculated through interpolation. Attempts to derive analytical models are based on neglecting the short-circuit current or approximating it by piecewise linear functions. The approach shown in this paper provides an approximate solution for the differential equation describing the dynamic behavor of an inverter circuit. It includes the influence of both transistor currents and a single load capacitance. The required values for timing and power analysis can be calculated with a small set of technology parameters for an arbitrary designed inverter. Compared to reference

  7. Experimental investigation and mathematical modelling of the combustion of brown coal, refuse and mixed fuels in a circulating fluidized bed combustor; Experimentelle Untersuchung und mathematische Modellierung der Verbrennung von Braunkohle, Abfallstoffen und Mischbrennstoffen in einer zirkulierenden Wirbelschichtfeuerung

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, W.; Brunne, T.; Hiller, A. [Technische Univ. Dresden (Germany). Inst. fuer Energietechnik; Albrecht, J. [Lurgi Umwelt GmbH, Frankfurt am Main (Germany); Quang, N. [Polytechnic Inst., Danang (Viet Nam)

    1998-09-01

    Extensive experiments on combustion of biological materials and residues in fluidized bed combustors and dust combustors have been carried out at the Department of Power Plant Engineering of Dresden University since the early nineties. Particular interest was taken in mixing brown coal with sewage sludge, sugar pulp and waste wood. The experiments were supplemented by modelling in a research project funded jointly by the BMBF and Messrs. Lurgi since early 1997. A combustion cell model designed by Siegen University is being modified for the new mixed fuels, and preliminary investigations were carried out on a batch reactor while the modelling work was continued. (orig.) [Deutsch] An dem Lehrstuhl fuer Kraftwerkstechnik der TU Dresden werden seit Anfang der 90-iger Jahre umfangreiche experimentelle Untersuchungen zur Verbrennung von Bio- und Reststoffen in Wirbelschicht- und Staubfeuerungen durchgefuehrt. Dabei war vor allem die Zufeuerung dieser Stoffe in Waermeerzeugeranlagen auf Braunkohlenbasis von besonderem Interesse. Experimentell konnte nachgewiesen werden, dass sowohl Biobrennstoffe als auch Abfaelle in zirkulierenden Wirbelschichtfeuerungen umweltschonend zur Waermeerzeugung eingesetzt werden koennen. Als Beispiel wird das an Hand von Braunkohle-Klaerschlammgemischen sowie Bagasse- und Holz-Braunkohlegemischen gezeigt. Neben den experimentellen Untersuchungen bietet die Modellierung der Verbrennungsvorgaenge ein geeignetes Mittel um Voraussagen zu anderen Mischungsanteilen sowie anderen geometrischen Abmessungen machen zu koennen. Seit Anfang 1997 wird dazu ein vom BMBF und der Firma Lurgi gefoerdertes Forschungsvorhaben bearbeitet. Ein von der Universitaet Gesamthochschule Siegen fuer die Braunkohleverbrennung konzipiertes Zellenmodell wird auf die neuen Brennstoffgemische erweitert. Da grundsaetzlich andere Stoffzusammensetzungen vorliegen, wurden an einem Batch-Reaktor Voruntersuchungen zum Pyrolyseverhalten der Brennstoffe durchgefuehrt. Erste

  8. Novel methods of process analysis and modelling of complex energy systems; Neuartige Methoden der Prozessanalyse und -modellierung energetischer Systeme

    Energy Technology Data Exchange (ETDEWEB)

    Busse, W. [Energie-Umwelt-Beratung e.V., Hohen Luckow (Germany)

    1993-12-31

    There is a trend towards greater complexity of maritime and stationary power plants. Different subsystems are combined to form highly integrated large systems. Examples are systems for energy supply from reproductive raw materials; systems combining different fossil and renewable energy resources; and maritime power plants. In these latter, traditionally complex, power plants increasing attention is being given to the interactions between individual subsystems and between the system and its environment. At the same time, the description of the state of a power plant and also its operational and process control are increasingly becoming oriented to complex target criteria. Beside traditional requirements such as maximum economic efficiency; maximum operating safety and security of supply; and serviceability etc. new criteria are attaining importance, expecially minimum environmental impact and minimum resources consumption. A transinterfacial, system-theoretical approach is needed for mastering these complex tasks. As energy systems become larger, so does the difficulty of giving exact mathematical descriptions of their processes and working out complete algorithms for solving problems of state description and process control. This difficulty can be attributed to our lack of knowledge of the behaviour of energy systems and the lack of signal descriptions available. (orig./HW) [Deutsch] Die Komplexitaet und Kompliziertheit maritimer und stationaerer Energieanlagen nimmt tendentiell zu. Aus unterschiedlichen Teilsystemen werden grosse Systeme mit einem hohem Vernetzungsgrad gebildet. Beispiele hierfuer sind: - Systeme zur Energieversorgung aus nachwachsenden Rohstoffen, - Kombination unterschiedlicher fossiler und regenerativer Energiequellen - bei den traditionell komplexen maritimen Energieanlagen werden in wachsendem Masse die Wechselwirkungen zwischen den Teilsystemen und zur Systemumgebung beruecksichtigt. Gleichzeitig orientieren sich Zustandsbestimmung

  9. Hydraulic modelling of the geothermal wells at Kreuzlingen and Konstanz; Hydraulische Modellierung der Geothermiebohrungen Kreuzlingen und Konstanz

    Energy Technology Data Exchange (ETDEWEB)

    Megel, T. [Inst. fuer Geophysik, Gruppe fuer Geothermik und Radiometrie, ETH Hoenggerberg, Zuerich (Switzerland); Wyss, R. [Ingenieurgelogie, ETH Hoenggerberg, Zuerich (Switzerland); Greber, E.; Leu, W. [Geoform, Geologische Beratungen und Studien AG, Winterthur (Switzerland)

    1997-12-01

    Aussuming an aquifer of minimum 30 km extension, modelling and interpretation of the hydraulic situation at the geothermal wells Konstanz and Kreuzlingen have shown, that there is neither a significant hydraulic nor a thermal interrelation between the two wells (assumed production rate: Konstanz 6.6 l/s, Kreuzlingen 3 l/s). Every hydraulic behaviour of supposed fracture zones between the two wells reduces the interrelated influence. (orig.) [Deutsch] Modellierungen und Interpretationen haben gezeigt, dass unter der Annahme eines mindestens 30 km ausgedehnten Aquifers die Geothermiebohrungen Konstanz und Kreuzlingen auch laengerfristig (30 Jahre) sich gegenseitig weder hydraulisch noch thermisch nennenswert beeinflussen (Konstanz 6.6 l/s, Kreuzlingen 3 l/s). Die Existenz von hydraulisch signifikanten Bruchzonen zwischen den beiden Bohrungen wuerde die gegenseitige Beeinflussung vermindern. (orig.)

  10. Numerical simulation and modeling of the unsteady flow in turbomachinery; Numerische Simulation und Modellierung der instationaeren Stroemung in Turbomaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Eulitz, F.

    2000-04-01

    The present work is devoted to the development of a computational technique for the Reynolds-averaged, time-resolved simulation of the undsteady, viscous flow in turbomachinery. After identification of model criteria, a novel turbulence and transition model, based on the extension of a one-equation turbulence model, is derived in order to incorporate the Reynolds-averaged effects of boundary-layer transition in unsteady turbomachinery flow. Preserving low numerical dissipation and dispersion errors, the explicit time integration method is accelerated through a time-consistent two-grid approach to allow for an efficient use of parallel computers. The model development is carefully assessed by considering various test cases of steady and unsteady turbine flow with various transition modes or of transonic channel flow with self-excited shock-oscillation. The application of the computational technique is demonstrated for the case of a single-stage, transonic compressor component and of a three-stage low-pressure turbine at low Reynolds-number operation. (orig.) [German] In dieser Arbeit wird ein numerisches Verfahren zur zeitgenauen Simulation der instationaeren, reibungsbehafteten Stroemung in Turbomaschinen auf Grundlage der Reynolds-gemittelten Navier-Stokes-Gleichungen entwickelt. Nach Aufarbeitung der Modellierungsanforderungen wird basierend auf einem Eingleichungsturbulenzmodell ein neuartiges Turbulenz- und Transitionsmodell abgeleitet, mit dem verschiedene Transitionsmoden der instationaeren Turbomaschinenstroemung in ihrer Reynolds-gemittelten Wirkung beschrieben werden koennen. Durch einen zeitkonsistenten Zweigitter-Ansatz wird die Zeitintegration fuer Navier-Stokes-Simulationen auf Parallelrechnern unter Wahrung geringer numerischer Phasen- und Amplitudenfehler beschleunigt. Die Entwicklung wird an einer Reihe von Testfaellen, zur stationaeren und instationaeren Turbinenstroemung mit unterschiedlicher Grenzschichttransition oder zur transsonischen

  11. Use of modeling and simulation in the planning, analysis and interpretation of ultrasonic testing; Einsatz von Modellierung und Simulation bei der Planung, Analyse und Interpretation von Ultraschallpruefungen

    Energy Technology Data Exchange (ETDEWEB)

    Algernon, Daniel [SVTI Schweizerischer Verein fuer technische Inspektionen, Wallisellen (Switzerland). ZfP-Labor; Grosse, Christian U. [Technische Univ. Muenchen (Germany). Lehrstuhl fuer Zerstoerungsfreie Pruefung

    2016-05-01

    Acoustic testing methods such as ultrasound and impact echo are an important tool in building diagnostics. The range includes thickness measurements, the representation of the internal component geometry as well as the detection of voids (gravel pockets), delaminations or possibly locating grouting faults in the interior of metallic cladding tubes of tendon ducts. Basically acoustic method for non-destructive testing (NDT) is based on the excitation of elastic waves that interact with the target object (e.g. to detect discontinuity in the component) at the acoustic interface. From the signal received at the component surface this interaction shall be detected and interpreted to draw conclusions about the presence of the target object, and optionally to determine its size and position (approximately). Although the basic underlying physical principles of the application of elastic waves in NDT are known, it can be complicated by complex relationships in the form of restricted access, component geometries, or the type and form of reflectors. To estimate the chances of success of a test is already often not trivial. These circumstances highlight the importance of using simulations that allow a theoretically sound basis for testing and allow easy optimizing test systems. The deployable simulation methods are varied. Common are in particular the finite element method, the Elasto Finite Integration Technique and semi-analytical calculation methods. [German] Akustische Pruefverfahren wie Ultraschall und Impact-Echo sind ein wichtiges Werkzeug der Bauwerksdiagnose. Das Einsatzspektrum beinhaltet Dickenmessungen, die Darstellung der inneren Bauteilgeometrie ebenso wie die Ortung von Kiesnestern, Delaminationen oder u.U. die Ortung von Verpressfehlern im Innern metallischer Huellrohre von Spannkanaelen. Grundsaetzlich beruhen akustische Verfahren zur Zerstoerungsfreien Pruefung (ZfP) auf der Anregung elastischer Wellen, die mit dem Zielobjekt (z. B. zu detektierende Ungaenze

  12. Analysis and modelling of the use of a nickel/metal hydride battery in the Autarkic Hybrid; Analyse und Modellierung des Einsatzes einer Nickel/Metallhydrid-Batterie im Autarken Hybrid

    Energy Technology Data Exchange (ETDEWEB)

    Angloher, J.; Wagner, U.

    1999-07-01

    The optimal operation of traction batteries in hybrid drive concepts requires a battery analysis and modelling in order to prepare the vehicle integration of the battery. In order to use a Ni/MH battery in the Autarkic Hybrid a battery management was set-up in the frame of the special research field 365, whose development depends on the measuring-technical analysis of the energetic battery performance and on a new method to determine the load condition. The contribution describes how neuronal networks can be used by extending conventional methods in order to better determine the actual load condition of the battery. (orig.) [German] Der optimale Betrieb von Traktionsbatterien in hybriden Antriebskonzepten erfordert die vorherige Batterieanalyse und -modellierung, um die Fahrzeugintegration der Batterie vorzubereiten. Fuer den Einsatz einer Ni/MH-Batterie im Autarken Hybrid wurde im Rahmen des Sonderforschungsbereichs 365 ein Batteriemanagement aufgebaut, dessen Entwicklung auf der messtechnischen Analyse des energetischen Batterieverhaltens und einem neuen Verfahren der Ladezustandsbestimmung basiert. Der Beitrag beschreibt, wie in Erweiterung herkoemmlicher Methoden neuronale Netze verwendet werden koennen, um den aktuellen Ladezustand der Batterie praeziser zu bestimmen. (orig.)

  13. Effects of jetties on semiterrestrial areas - field testing and numerical modelling; Auswirkungen von Buhnen auf semiterrestrische Flaechen - Feldbeprobung und numerische Modellierung

    Energy Technology Data Exchange (ETDEWEB)

    Krebs, M. [TU Darmstadt (Germany). Inst. fuer Wasserbau und Wasserwirtschaft

    2000-07-01

    Five jetty fields of the middle section of the Elbe river between km 418 and 427 were selected according to different hydrodynamic and morphodynamic characteristics, and their abiotic and biotic characteristics were analyzed in an extensive measuring programme. Abiotic field data (sediment analyses, ADCP velocity profiles, ADV measurements) were used for adapting numerical models to solve hydrodynamic and morphodynamic problems, for validating measurements, and for calculating scenarios. Particular interest was taken in the changes brought about by the high water period of November 1998. [German] An der mittleren Elbe bei km 418 und 427 wurden fuenf Buhnenfelder nach unterschiedlichen hydro- und morphodynamischen Merkmalen ausgewaehlt und nach einem umfangreichen Messprogramm bezueglich Abiotik und Biotik untersucht (siehe auch Beitrag des Teilprojektes Biologie). Aufgenommene abiotische Felddaten wie Sedimentanalysen, ADCP-Geschwindigkeitsprofile und ADV-Messungen werden verwendet, um numerische Modelle fuer hydro- und morphodynamische Fragestellungen anzupassen und die Messergebnisse zu ueberpruefen bzw. Szenarien zu berechnen. Dabei sind besonders diejenigen Veraenderungen Gegenstand der Untersuchung, die das Hochwasser im November 1998 verursachten. (orig.)

  14. Linear open-loop and closed-loop control theory. Modelling of control paths, robust stability, design of robust controllers, trajectory control with follow-up contorl, polynomial description of MIMO systems, time discrete control loops and scanning control loops; Lineare Regelungs- und Steuerungstheorie. Modellierung von Regelstrecken, Robuste Stabilitaet und Entwurf robuster Regler, Trajektoriensteuerung mit Folgeregelung, Polynomiale Beschreibung von MIMO-Systemen, Zeitdiskrete und Abtastregelkreise

    Energy Technology Data Exchange (ETDEWEB)

    Reinschke, K. [Technische Univ. Dresden (Germany). Inst. fuer Regelungs- und Streuerungstheorie

    2006-07-01

    After the introduction of bachelor and master studies in Germany, new training concepts are required. In the field of engineering, there is a lack of research-oriented German-language textbooks which are also suited for further training of professionally experienced engineers. The author addresses readers with good prior knowledge of mathematics and application-oriented basic training in open-loop and control-loop engineering who intend to deepen their knowledge of the methods of control of linear time-continuous processes. The reader is enabled to apply the mathematical tools of linear system theory for control purposes. Unavoidable uncertainties in the modelling of control paths are considered. The focus is on function theoretical and algebraic aspects which enable the design of robust stabilising controllers as well as trajectory control and follow-up control and also the time-continuous treatment of scanning control loops. There are many examples to illustrate the general laws that are presented. (orig.) [German] Die Einfuehrung von gestuften Bachelor- und Master-Studiengaengen erfordert neue Ausbildungskonzepte. Fuer die Master- und Promotionsstudiengaenge der Ingenieure mangelt es bisher an forschungsorientierten deutschsprachigen Lehrwerken, die zugleich auch zur Fortbildung von berufserfahrenen Ingenieuren geeignet sind. Dieses Buch traegt zur Behebung dieses Mangels bei. Der Autor wendet sich an Leser, die eine gute mathematische Vorbildung und eine anwendungsorientierte Grundausbildung in Regelungs- und Steuerungstechnik abgeschlossen haben und nun tiefer in die Methoden der Regelung und Steuerung von linearen zeitkontinuierlichen Prozessen eindringen wollen. Der Leser wird befaehigt, die mathematischen Werkzeuge der linearen Systemtheorie fuer regelungstechnische Zwecke einzusetzen. Bei der Modellierung von Regelstrecken werden die unvermeidlichen Unbestimmtheiten beruecksichtigt. Im Zentrum stehen die funktionentheoretischen und algebraischen

  15. Investigation and modelling of fuel utilisation in the zone near the burner of technical combustion systems. Final report; Untersuchung und Modellierung der Brennstoffumsetzung im Brennernahbereich technischer Verbrennungssysteme. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, H.; Wirtz, S.

    1999-06-01

    Optimisation and development of technical combustion systems in order to generate energy efficiently and reduce pollution is an ever-increasing challenge. Mathematical and numerical simulations play a very important role in this context. This project was dedicated to the implementation and improvement of mathematical models and subsequent verification of the modelling concepts. Verification used data measured by the university department for combined cyle turbines. The focal point of interest was the reaction zone near the burner. Further points of interest: development and improvement of models for two-phase effects, fuel consumption and turbulence interaction as well as further development of the methods of numerical simulation. Simulating the combustion chamber of the combined cycle turbines was prioritised.(orig.) [German] Die Optimierung und Weiterentwicklung technischer Verbrennungssysteme mit dem Ziel einer moeglichst effizienten und schadstoffarmen Energiebereitstellung stellt eine staendig wachsende Herausforderung dar. Bei der technologischen Umsetzung dieses Ziels kommt der mathematisch-numerischen Simulation eine immer groessere Bedeutung zu. In diesem Projekt sollte die Implementierung und Verbesserung von mathematischen Modellierungsansaetzen sowie die anschliessende Verifikation der Modellierungskonzepte anhand der Messdaten des Lehrstuhls fuer Dampf- und Gasturbinen (LDuG) durchgefuehrt werden. Der Schwerpunkt lag in der brennernahen Reaktionszone. Konkrete Arbeitsschwerpunkte waren die Weiterentwicklung und Verbesserung der Modellansaetze fuer Zweiphaseneffekte, Brennstoffumsatz und Turbulenzinteraktion sowie die Weiterentwicklung der Methodik der numerischen Simulation. Dabei stand die Simulation der Brennkammer des LDuG im Vordergrund. (orig.)

  16. Theory and numeric modelling of non-isothermal multiphase processes in NAPL-contaminated porous media; Theorie und numerische Modellierung nichtisothermer Mehrphasenprozesse in NAPL-kontaminierten poroesen Medien

    Energy Technology Data Exchange (ETDEWEB)

    Class, H.

    2000-07-01

    The author investigates the numeric simulation of physical processes in porous media. The development of the model and its components is described, and the model is validated by laboratory experiments. Differences from the discretization methods BOX and CVFE are discussed as well as the applicability of the multigrid method described for multicomponent approaches. [German] Bei der thermischen Sanierung NAPL-kontaminierter Standorte, z.B. durch Injektion von Wasserdampf und/oder Heissluft, treten nichtisotherme Mehrphasenprozesse auf, die in einem Modell durch eine Betrachtung der Stroemungs- und Transportprozesse als Mehrkomponentensystem beschrieben werden koennen. Dabei ist der Austausch thermischer Energie zwischen den Phasen untereinander und auch dem poroesen Medium selbst, wie auch der Uebergang von Massekomponenten zwischen den Phasen zu beruecksichtigen. Die vorliegende Arbeit behandelt die numerische Simulation derartiger physikalischer Vorgaenge in poroesen Medien. Ausgehend von der Problemstellung wird die Entwicklung eines konzeptionellen Modells (Kap. 2) sowie die Umsetzung der daraus resultierenden mathematischen Gleichungen und dazu erforderlichen Diskretisierungs- und Loesungsmethoden in numerische Algorithmen dargestellt (Kap. 3). Anschliessend wird in Kap. 4 die Faehigkeit des erstelten numerischen Modells ueberprueft, Problemstellungen in natuerlichen Systemen zu simulieren (Vergleich mit Laborexperimenten); ausserdem werden Unterschiede der Diskretisierungsverfahren BOX und CVFE sowie die Anwendbarkeit des in dieser Arbeit fuer Mehrkomponentenformulierungen erweiterten Mehrgitterverfahrens diskutiert. (orig.)

  17. Mechanistic investigation and modelling of anode reaction in the molten carbonate fuel cell; Mechanistische Untersuchung und Modellierung der Anodenreaktion in der Karbonat-Brennstoffzelle

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, Markus Roman

    2011-04-27

    detaillierte Kenntnisse der an den Elektroden ablaufenden Reaktionsmechanismen. In der vorliegenden Arbeit wird der komplexe anodenseitige Reaktionsmechanismus in der Karbonat-Brennstoffzelle detailliert untersucht, mit dem Ziel, ein grundlegendes Verstaendnis ueber die an der Anode stattfindenden physikalischen und elektrochemischen Prozesse zu entwickeln und Einflussgroessen auf die Leistung der Brennstoffzellen-Stapel zu identifizieren. Dazu zaehlen die eingehende Untersuchung der parallel stattfindenden Oxidationsreaktionen von Wasserstoff und Kohlenmonoxid und ihrer reaktionstechnischen Parameter, die detaillierte Analyse von Stofftransport, Adsorption und Ladungstransport und die Betrachtung von Degradationsphaenomenen, welche sich degressiv auf Zellleistung und Lebensdauer auswirken. Fuer die experimentellen Untersuchungen stehen verschiedene Versuchsanlagen zur Verfuegung. Dazu zaehlen vorrangig Anoden-Halbzellen und Einzelzellen. Werkzeug zur Analyse der physikalischen und elektrochemischen Phaenomene ist die elektrochemische Impedanzspektroskopie (EIS), deren Ergebnisse in die Entwicklung eines Ersatzschaltbilds einfliessen. Die Verknuepfung der Elemente des Ersatzschaltbilds mit physikalischen Prozessgroessen erfolgt im Rahmen eines numerischen Modells fuer die MCFC-Anode. Die Impedanzspektren der MCFC-Anoden ergeben vier charakteristische Widerstaende: ohmscher Widerstand, hochfrequenter Widerstand, niederfrequenter Widerstand und Gesamtwiderstand. Der stark temperaturabhaengige hochfrequente Widerstand wird von der Elektrodenkinetik beeinflusst, waehrend der Stofftransport durch den niederfrequenten Widerstand ausgedrueckt wird. Es zeigt sich, dass die in der Literatur postulierten Mechanismen fuer die anodenseitige Oxidation von Wasserstoff unvollstaendig sind. Die Oxidation des Wasserstoffs folgt einer Reaktionsgeschwindigkeit (pseudo) negativer Ordnung. Voraussetzung hierfuer sind zwei adsorbierende, miteinander reagierende Spezies. Mithilfe der numerischen

  18. Innovations and airborne pollutants. An economic assessment of the influence of different boundary conditions with explicit modelling of the choice of technology in the industrial sector. Interim report - documentation for the steel industry; Innovationen und Luftschadstoffemissionen. Eine gesamtwirtschaftliche Abschaetzung des Einflusses unterschiedlicher Rahmenbedingungen bei expliziter Modellierung der Technologiewahl im Industriesektor. Zwischenbericht - Dokumentation Stahlindustrie

    Energy Technology Data Exchange (ETDEWEB)

    Schleich, J.; Nathani, C.; Ostertag, K.; Schoen, M.; Walz, R.; Meyer, B.; Lutz, C.; Distelkamp, M.; Wolter, M.I.; Hohmann, F.

    2002-04-01

    The project attempted an improved modelling of technological progress. For this, the basic technological processes of selected energy-intensive sectors of the econometric input-output model PANTA RHEI are mapped in a model-consistent systematics. Technological progress is assumed to derive from the modelled decision making behaviour during selection of a technology. Apart from an improved assessment of the economic and environmental effects of political decisions, also the innovation effects are modelled. Further, politically induced technological progress is reduced explicitly to technologies. [German] Ziel des Projekts ist eine methodisch verbesserte Modellierung des technischen Fortschritts. Dazu werden fuer ausgewaehlte energieintensive Branchen des oekonometrischen Input-Output Modells PANTA RHEI die zugrunde liegenden technologischen Prozesse in einer modellkonsistenten Systematik abgebildet. Ein weiteres innovatives Element besteht darin, dass technischer Fortschritt auf das modellierte Entscheidungsverhalten bei der Technikwahl zurueckgefuehrt werden kann. Die gewaehlte Modellierung erlaubt nicht nur eine verbesserte Abschaetzung der durch Politikmassnahmen ausgeloesten gesamtwirtschaftlichen und der umweltrelevanten Wirkungen, sondern auch eine Bewertung der Innovationseffekte. Ausserdem laesst sich politik-induzierter, technischer Fortschritt explizit auf Technologien zurueckfuehren. (orig.)

  19. Mathematical modelling and simulation of solar-assisted drying of bulk farm products; Mathematische Modellierung und Simulation der solar unterstuetzten Trocknung landwirtschaftlicher Schuettgueter

    Energy Technology Data Exchange (ETDEWEB)

    Maltry, W.; Ziegler, T.; Richter, I.

    1997-04-01

    The report deals with problems associated with the harnessing of solar energy for drying bulk farm products: technical fundamentals, enthalpy diagrams, models for grain drying, experimental investigations, analysis of drying processes, benefits and applications of drying processes, advances. (HW) [Deutsch] Der Bericht behandelt die Probleme der Solarenergienutzung zur Trockung landwirtschaftlicher Massengueter: - Trocknungstechnische Grundlagen - Enthalpie-Diagramme - Modelle zur Koernertrocknung - experimentelle Untersuchungen - Analyse von Trocknungsprozesse - Nutzen und Verwertbarkeit der Trocknungsprozesse - Fortschritte. (HW)

  20. Risks of a coastal region in case of climate changes: economic evolution and spatial modelling of the damage potential in the lower Weser region; Risiko einer Kuestenregion bei Klimaaenderung: Oekonomische Bewertung und raeumliche Modellierung des Schadenspotentials in der Unterweserregion

    Energy Technology Data Exchange (ETDEWEB)

    Kiese, M.; Leineweber, B.

    2001-07-01

    der Nutzen einer Kuestenschutzmassnahme dem im Versagensfall (''wenn die Flut kommt'') vermiedenen Schaden. Unter sonst gleichen Bedingungen sind Ausbaumassnahmen dort vorzuziehen, wo das Schadenspotential im Hinterland am groessten ist. Der von der Abteilung Wirtschaftsgeographie des Geographischen Instituts an der Universitaet Hannover bearbeitete Teil des Projektes ''Risiko einer Kuestenregion bei Klimaaenderung: Oekonomische Bewertung und raeumliche Modellierung des Schadenspotentials in der Unterweserregion Bremerhaven - Butjadingen - Land Wursten'' soll die hinter dem Deich liegenden ''geschuetzten Werte'' erfassen, monetaer bewerten und raeumlich modellieren. Mit Schadensfunktionen belegt, ergeben die so ermittelten geschuetzten Werte das Schadenspotential, mit dem im Falle einer Ueberflutung zu rechnen waere. Die Ergebnisse dieses Projektes fliessen in das Forschungsvorhaben ''Risiko einer Kuestenregion bei Klimaaenderung'' ein, das das Franzius-Institut fuer Wasserbau und Kuesteningenieurwesen in Zusammenarbeit mit der Abteilung Wirtschaftsgeographie durchfuehrt. (orig.)

  1. Nuisance forecasting. Univariate modelling and very-short-term forecasting of winter smog episodes; Immissionsprognose. Univariate Modellierung und Kuerzestfristvorhersage von Wintersmogsituationen

    Energy Technology Data Exchange (ETDEWEB)

    Schlink, U.

    1996-12-31

    The work evaluates specifically the nuisance data provided by the measuring station in the centre of Leipig during the period from 1980 to 1993, with the aim to develop an algorithm for making very short-term forecasts of excessive nuisances. Forecasting was to be univariate, i.e., based exclusively on the half-hourly readings of SO{sub 2} concentrations taken in the past. As shown by Fourier analysis, there exist three main and mutually independent spectral regions: the high-frequency sector (period < 12 hours) of unstable irregularities, the seasonal sector with the periods of 24 and 12 hours, and the low-frequency sector (period > 24 hours). After breaking the measuring series up into components, the low-frequency sector is termed trend component, or trend for short. For obtaining the components, a Kalman filter is used. It was found that smog episodes are most adequately described by the trend component. This is therefore more closely investigated. The phase representation then shows characteristic trajectories of the trends. (orig./KW) [Deutsch] In der vorliegende Arbeit wurden speziell die Immissionsdaten der Messstation Leipzig-Mitte des Zeitraumes 1980-1993 mit dem Ziel der Erstellung eines Algorithmus fuer die Kuerzestfristprognose von Ueberschreitungssituationen untersucht. Die Prognosestellung sollte allein anhand der in der Vergangenheit registrierten Halbstundenwerte der SO{sub 2}-Konzentration, also univariat erfolgen. Wie die Fourieranalyse zeigt, gibt es drei wesentliche und voneinander unabhaengige Spektralbereiche: Den hochfrequenten Bereich (Periode <12 Stunden) der instabilen Irregularitaeten, den saisonalen Anteil mit den Perioden von 24 und 12 Stunden und den niedrigfrequenten Bereich (Periode >24 Stunden). Letzterer wird nach einer Zerlegung der Messreihe in Komponenten als Trendkomponente (oder kurz Trend) bezeichnet. Fuer die Komponentenzerlegung wird ein Kalman-Filter verwendet. Es stellt sich heraus, dass Smogepisoden am deutlichsten

  2. Mathematical modelling of the performance of hydrodynamic couplings using hybrid models; Mathematische Modellierung des Betriebsverhaltens hydrodynamischer Kupplungen mit hybriden Modellansaetzen

    Energy Technology Data Exchange (ETDEWEB)

    Jaschke, P.

    2000-02-01

    Mathematical models of the dynamic performance of hydrodynamic couplings are developed using hybrid modelling, i.e. a combination of analytical physical modelling and black box identification. The models developed were verified by measurements on a model powertrain. [German] In dieser Arbeit werden mit Hilfe der hybriden Modellierung mathematische Modelle zur Beschreibung des dynamischen Betriebsverhaltens hydrodynamischer Kupplungen ermittelt. Die Hybride Modellierung stellt eine Kombination der analytisch physikalischen Modellierung und der Black-Box-Identifikation dar. Diese Modellierungsart ist ausgewaehlt worden, um die Vorteile der analytisch physikalischen Modellierung und der Black-Box-Identifikation hydrodynamischer Kupplungen zu verbinden und deren Nachteile gering zu halten. Auf dieser Basis ist eine Vorgehensweise vorgestellt worden, die die Ermittlung der Modelle mit wenig Aufwand ermoeglicht. Mit Hilfe der Modelltheorie wird gezeigt, wie die ermittelten mathematischen Modelle zur Simulation des dynamischen Betriebsverhaltens geometrisch aehnlicher Kupplungen unterschiedlicher Baugroessen verwendet werden koennen. Darueber hinaus wird dargelegt, wie die ermittelten Modelle mit Modellen anderer Antriebsstrangelemente gekoppelt werden koennen, um Antriebsstrangsimulationen zu ermoeglichen. Verifikationsmessungen an einem Modellantriebsstrang verdeutlichen die Guete und Verwendbarkeit der mathematischen Modelle. (orig.)

  3. Three-dimensional dynamic modelling of Polymer-Electrolyte-Membrane-Fuel-Cell-Systems; Dreidimensionale dynamische Modellierung und Berechnung von Polymer-Elektrolyt-Membran-Brennstoffzellen

    Energy Technology Data Exchange (ETDEWEB)

    Vath, Andreas

    2008-12-15

    This thesis deals with dynamic and multi-dimensional modelling of Polymer- Electrolyte-Membrane-Fuel-Cells (PEMFC). The developed models include all the different layers of the fuel cell e.g. flow field, gas diffusion layer, catalyst layer and membrane with their particular physical, chemical and electrical characteristics. The simulation results have been verified by detailed measurements performed at the research centre for hydrogen and solar energy in Ulm (ZSW Ulm). The developed three dimensional model describes the time- and spatial-dependent charge and mass transport in a fuel cell. Additionally, this model allows the analysis of critical operating conditions. For example, the current density distribution for different membranes is shown during insufficient humidification which results in local overstraining and degradation. The model also allows to analyse extreme critical operating conditions, e.g. short time breakdown of the humidification. Furthermore, the model shows the available potential of improvement opportunities in power density and efficiency of PEMFC due to optimisation of the gas diffusion layer, the catalyst and membrane. In the second part of the work the application of PEMFC systems for combined heat and power units is described by one-dimensional models for an electrical power range between 1 kW and 5 kW. This model contains the necessary components, e.g. gas processing, humidification, gas supply, fuel cell stack, heat storage, pumps, auxiliary burner, power inverter und additional aggregates. As a main result, it is possible to distinctly reduce the energy demand and the carbon dioxide exhaust for different load profiles. Today the costs for fuel cell systems are considerably higher than that of the conventional electrical energy supply. (orig.)

  4. Investigation and modelling of release and transport processes of alkaline substances in high-pressure coal combustion processes. Final report; Untersuchung und Modellierung der Freisetzungs- und Transportvorgaenge von Alkalien bei der Kohleverbrennung unter hohen Druecken. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, H.; Wirtz, S.; Mueller, C.; Murza, S.; Scheuer, S.; Mohr, M.

    2000-06-01

    On the basis of IWE and DMT-FuelTec measurements on the release of alkaline components in coal dust combustion processes, a model for mathematical description of these processes was developed at LEAT and was integrated in the LEAT CFD code LORA. This required extensive further development and enhancement of the basic program available at the beginning of the project, especially the parallelization of the Lagrangian particle trackings and the improvement and enhancement of the description of the chemical and physical particle reactions. As a comparison with measurements showed, this results in an acceptably accurate description of the processes. The results of the project were applied in further LEAT projects and were also supported by experimental projects, making use of synergies and achieving clear progress in the description of combustion systems. Further developments of the model components are already used in industrial applications. [German] Auf der Grundlage von bei IWE und DMT-FuelTec durchgefuehrten Messungen zur Freisetzung von Alkalikomponenten bei der Kohlenstaubverbrennung ist am LEAT ein Modellansatz zur mathematischen Beschreibung dieser Vorgaenge entwickelt und in den am LEAT entwickelten CFD-Code LORA integriert worden. Dazu war eine umfangreiche Weiterentwicklung und Ergaenzung des zu Projektbeginn vorhandenen Basisprogramms notwendig. Dies betraf vor allem die Parallelisierung des Lagrange'schen Partikeltrackings und die Verbresserung bzw. Erweiterung der Beschreibung der chemischen und physikalischen Partikelreaktionen. Wie der Vergleich mit Messungen zeigt [9, 36], ist damit eine brauchbare Beschreibung der Vorgaenge moeglich. Die in diesem theoretisch orientierten Projekt erarbeiteten Ergebnisse sind sowohl in weitere Projekte des LEAT eingeflossen, als auch durch andere, experimentell ausgerichtete Projekte unterstuetzt worden. Insgesamt wurden dadurch Synergien genutzt und ein deutlicher Fortschritt bei der Beschreibung entsprechender

  5. Emotionale Framing-Effekte auf Einstellungen: eine theoretische Modellierung und empirische Überprüfung der Wirkungsmechanismen [Emotional framing effects on attitudes: a theoretical model and empirical investigation of the underlying mechanisms

    NARCIS (Netherlands)

    Kühne, R.

    2015-01-01

    Der wirkungsorientierte Framing-Ansatz fokussierte traditionell kognitive Effekte der Medienberichterstattung auf die Einstellungen von Rezipientinnen und Rezipienten. Aktuelle Befunde zeigen allerdings, dass in Rezeptions- und Meinungsbildungsprozessen auch Emotionen eine bedeutende Rolle spielen.

  6. Mathematical modelling of deuterium transport in field lysimeters; Mathematische Modellierung des Deuteriumtransports in Freilandlysimetern

    Energy Technology Data Exchange (ETDEWEB)

    Maloszewski, P.; Klotz, D.; Trimborn, P. [GSF - Forschungszentrum fuer Umwelt und Gesundheit GmbH, Neuherberg (Germany). Inst. fuer Hydrologie; Maciejewski, S. [Polish Academy of Sciences, Gdansk (Poland). Inst. of Hydroengineering

    1999-02-01

    The results yielded by the Variable Flow Model (VFDM) permitted determining water flow velocities and degrees of dispersiveness. It transpired that it is not possible to isolate immobile water, which is to say that the available measuring and modelling data permit no conclusion as to whether or not the system contains immobile water. Comparison with the results obtained with the Dispersion Model (DM) showed that the simpler DM model yields tracer concentration curves in the system output that are almost as good as those of the more complicated VFDM model while entailing less work. The two models yield very similar calculations of lysimeter water content. [Deutsch] Die Ergebnisse der Modellierung mit dem Variable-Flow-Modell (VFDM) ermoeglichten die Bestimmung von Wassergeschwindigkeiten des Wassers und Dispersivitaeten. Es wurde dabei festgestellt, dass eine Abtrennung des immobilen Wassers nicht moeglich ist. D.h. es kann nicht auf Grund vorhandener Messdaten und der Modellierung entschieden werden, ob das System immobiles Wasser beinhaltet oder nicht. Ein Vergleich der Ergebnisse nach dem Variable-Flow- und dem Dispersions-Modell (DM) zeigte, dass das einfache Modell DM mit weniger Aufwand fast so gute Tracerkonzentrationskurven im Output aus dem System liefert wie das komplizierte Modell mit VFDM. Die berechneten Wassergehalte der Lysimeter nach beiden Modellierungen sind sehr aehnlich. (orig.)

  7. Aspects of numerical modelling in expert practice; Aspekte der numerischen Modellierung in der gutachterlichen Praxis

    Energy Technology Data Exchange (ETDEWEB)

    Schaedler, G.

    1998-01-01

    Referring to a relatively restricted field, namely the preparation of expertises in small-scale climatology and air hygiene, the paper wants to give insight into the methods of, and the problems associated with, the numerical modellings used. Frequently occurring tasks are described, the numerical models used are briefly outlined, and some of the problems are discussed which are encountered when using these models. (orig./KW) [Deutsch] Der vorliegende Aufsatz soll am Beispiel eines relativ eng umgrenzten Themenkreises, naemlich der gutachterlichen Taetigkeit im Bereich der kleinraeumigen Klimatologie und Lufthygiene, einen Einblick in die Methoden und Probleme der dabei eingesetzten numerischen Modellierung geben. Zunaechst werden haeufig auftretende Aufgabenstellungen dargestellt, dann die verwendeten numerischen Modelle kurz vorgestellt und schliesslich einige der Probleme angesprochen, die sich beim praktischen Einsatz dieser Modelle stellen. (orig./KW)

  8. Mathematical modelling of transport of gaseous and liquid substances induced by pyrite oxidation in spoil banks of lignite mines; Mathematische Modellierung der durch Pyritoxidation induzierten Stofftransporte in Braunkohleabraumkippen in gasfoermiger und fluessiger Phase

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, R.

    2001-07-01

    Pyrite (FeS{sub 2}) oxidation due to open-pit lignite mining activities may result in acid mine drainage and dissolved metals in the soil and ground water of the overburden spoil piles. The pyrite oxidation takes place firstly during the mining process and at the temporary surfaces of the mine, secondly in deep zones of the overburden spoil pile as a result of gas transport through the unsaturated zone. The second process continues after mine closure possibly over several decades and therefore contaminates the environment for a long time. Whereas some studies deal with a minimisation by geochemical means, this research focuses on a minimisation by impacting the physical boundary conditions. Special attention is given to the transport of oxygen from the soil surface to the pyrite oxidation zone. Soil column experiments with columns of 2.90 m height yield experimental data concerning the pyrite oxidation and the related transport processes in the unsaturated zone. Experimental data are compared to simulation results obtained with the model MUSIC; it calculates coupled reaction and transport processes in a one-dimensional soil profile using the finite volume method. Pyrite oxidation is described by means of a first order kinetics, the gas transport takes place by diffusion as well as convection. The transport of solutes in the soil water is described by the convection-dispersion equation (Cl{sup -}, Fe{sup 2+} and SO{sub 4}{sup 2-}). The simulations are able to reproduce the measured time series of oxygen concentrations in the soil profile. (orig.) [German] Die durch Braunkohlegewinnung im Tagebau hervorgerufene Pyritoxidation (Pyrit: FeS{sub 2}) kann zu Versauerung, Schwermetallfreisetzung und Aufmineralisierung des Boden- und Grundwassers in den Abraumkippen fuehren. Die Pyritoxidation findet zum einen waehrend des Abbaubetriebs und an den temporaeren Oberflaechen des Tagebaus statt, zum anderen in tieferen Bereichen der Abraumkippe durch Gastransport durch die

  9. Investigation and modelling of the alkaline release and transport during coal combustion at elevated pressures. Final report; Untersuchung und Modellierung der Freisetzungs- und Transportvorgaenge von Alkalien bei der Kohleverbrennung unter hohen Druecken. Untersuchungen mit der Hochdruck-Hochtemperatur-Thermowaage, Alkalienanalysen in Rohkohlen und Feuerungsversuche in der Druckwirbelschichtanlage FRED (DMT). Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Bonn, B.; Steffin, C.; Busch, U.; Mayer, M.

    2000-07-01

    In this joint research project DMT investigated the release (and incorporation) of alkalis of the coal mineral matter to clear up the affecting mechanisms during combustion at elevated pressure. In the experiments parameter like the ambient gas and the ash composition, pressure and heating rate were varied. The experiments were conducted in DMT's high-temperature and high-pressure Thermogravimetric-Analyser (TGA) and the DMT Pressurised Fluidised Bed Combustor (PFBC). TGA-Experiments: A model compounds for the alkali sodium chloride and for the mineral matter metakaoline were used. The chemical properties (basicity) of metakaoline was modified by adding CaO. The commonly accepted physical volatilization process of the alkali from the ash was not confirmed by TGA experiments. The alkali release must be regarded as a desorption mechanism of the sodium chloride from the metakaoline surface. The desorption of the alkali is not affected by chemical composition of the mineral matter but is strongly influenced by gas phase oxygen species and pressure. PFBC-Experiments: The rig was operated with a fluidised bed temperature of 920 C and a pressure of 7 bar. The online/in-situ alkali detection was based on the excimer laser induced fragmentation fluorescence ELIF. The alkali content of the coal was varied by addition of sodium acetate and sodium chloride. Kaoline was used as gettermaterial for mitigation of alkali emissions. Furthermore, the influence of limestone on the alkali release was investigated. Among other results, the experiments showed that the alkali emissions of the lignite are 50-100 times higher than those of the bituminous coal and if limestone for capturing SO{sub 2} is added to the combustor the alkali chloride emissions increase rapidly. (orig.) [German] Im Rahmen des o.g. Gemeinschaftsprojekts untersuchte die DMT die Freisetzung (und Einbindung) der Alkalien aus der Mineralsubstanz von Kohlen zur Aufklaerung der beeinflussenden Mechanismen bei der

  10. Modelling and calculation of combined-cycle power plants with pressurized fluidized bed and with upstream or downstream gas turbines at full load and part load; Modellierung und Berechnung von Kombikraftwerken mit Druckwirbelschicht und vor- sowie nachgeschalteten Gasturbinen bei Voll- und Teillast

    Energy Technology Data Exchange (ETDEWEB)

    Faatz, R.

    1997-12-31

    Owing to their high efficiency, low pollutant emissions and good performance when fuelled with coal, pressurized fluidized-bed combustors have come to play and important role. The performance of processes with pressurized fluidized beds can be enhanced significantly by combining them with gas turbines fuelled with natural gas or coal gas. The report describes several variants of combined cycle processes with pressurized fluidized beds and with gas turbines connected upstream or downstream. The main components, i.e. gas turbine, pressurized fluidized bed, steam turbine and steam cycle are simulated by computer models. For the power plant variants, full-load calculations were carried out to determine the potential efficiency; for the components like gas turbine and pressurized fluidized bed, also part-load calculations were made. It was found that efficiencies of 45-49 % are possible with the investigated variants. Optimisation of the process parameters, efficiencies up to 51.4 % will be possible especially in the range of transition to supercritical steam parameters. (orig.) 68 figs., 14 tabs. [Deutsch] Die Druckwirbelschichtfeuerung hat wegen ihres hohen Wirkungsgrades, ihrer niedrigen Schadstoffemissionen und ihrer Eignung fuer den Brennstoff Kohle eine grosse Bedeutung erlangt. Durch geschickte Kombination mit erdgas- oder kohlegasgefeuerten Gasturbinen laesst sich der Wirkungsgrad von Prozessen mit Druckwirbelschicht betraechtlich steigern. Die vorliegende Arbeit beschreibt verschiedene Schaltungsvarianten von Kombiprozessen mit Druckwirbelschicht, bei denen die Gasturbinen der Wirbelschicht sowohl vorgeschaltet als auch nachgeschaltet sind. Die Hauptkomponenten der Prozesse wie Gasturbine, Druckwirbelschicht, Dampfturbine und Dampfkreislauf werden durch Rechnermodelle simuliert. Fuer die Kraftwerksvarianten wurden Vollastrechnungen zur Ermittlung des Wirkungsgradpotentials, fuer die einzelnen Komponenten wie Gasturbine und Druckwirbelschicht auch

  11. Microbial reduction of methane emissions. Subproject 1: Development of a biofilter system for the degradation of methane, odours and trace gases for actively vented landfills. Subproject 2: Development of a biofilter system for the degradation of methane, odours and trace gases for passively vented landfills. Subproject 3: Planning, development and realisation of medium and large scale biofilter plants at active and passive gas drainage systems. Final report; Mikrobielle Verminderung von Methanemissionen. Teilvorhaben 1: Entwicklung eines Biofilterverfahrens zum Abbau von Methan, Geruechen und Spurengasen bei der aktiven Deponieentgasung. Teilvorhaben 2: Entwicklung eines Biofilterverfahrens zum Abbau von Methan, Geruechen und Spurengasen bei der passiven Deponieentgasung. Teilvorhaben 3: Planung, Entwicklung und Realisation halb- und grosstechnischer Biofilteranlagen an aktiven und passiven Entgasungssystemen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Stegmann, R.; Streese, J.; Dammann, Bernd; Gebert, J.; Groengroeft, A.; Miehlich, G.; Schulze, H.; Berndt, M.

    2003-07-01

    Old landfills may emit considerable amounts of methane, carbon dioxide and trace gases. However, gas flow rate and methane content are usually too low for energetic utilization or flaring of the landfill gas. Microbial degradation is considered an alternative treatment for the reduction of methane emissions from those sites. The project aimed in the investigation of the suitability of actively vented biofilters for this purpose and the collection of operational experience and dimensioning data for large scale applications of the process. Different experimental plants were operated in laboratory scale (filter volume: 60 L) and container scale (filter volume: 4 m{sup 3}). The laboratory scale plant was operated with synthetic methane, whereas the container scale plant was set up at an old landfill and operated with real landfill gas. For each plant, the gas was diluted with ambient air prior to feeding into the closed biofilters, thus sufficient oxygen for methane oxidation was present throughout the filter material. At first, fine-grained compost as biofilter material was investigated. A biofilter unit of 15 m{sup 3} size containing porous clay pellets as filter material was integrated into the recultivation layer of a Hamburg harbour sludge landfill. The parameters of landfill gas emission as well as the abiotic parameters of biofilter operation were monitored by a high-resolution automatic data collection system and gas distribution and gas emissions via the biofilter surface measured regularly. In addition, microbiological laboratory studies and studies concerning physical questions of biofilter operations were conducted. (orig.)

  12. BIOFILTERS IN AQUACULTURE

    Directory of Open Access Journals (Sweden)

    Ivo Šarić

    2010-07-01

    Full Text Available Recirculating aquaculture is one of the solutions to an environmentally sustainable and economically feasible aquaculture production, and can be established in either urban or rural communities. Controlled conditions enable optimal growth conditions suitable for the species in question during the whole growth process, as well as the shortening of the process itself, when compared to open uncontrolled systems. Recirculating systems are now one of the most researched fields of aquaculture, and biofiltration as the reduction of the poisonous ammonia compounds generated by digestion of proteins, is one of its most important parts. The aim of this study was to stress the importance of biofiltration, and to describe different designs of biofilters. Many biofilters are being used in commercial and research aquaculture facilities with differences in choice of working organism, design, material, price and etc. For the proper choice of biofilter it is necessary to know characteristics of each recirculating aquaculture system, because there are still no strict criteria for categorizing and applying different biofilter designs.

  13. Developing a model system for simulation of changes induced by more effective circular flow concepts in industry and energy management. Systems technology and economic modelling aspects shown with the example of the materials flow in the paper industry; Entwicklung eines Modellsystems zur Simulation der energiewirtschaftlichen und strukturellen Veraenderungen einer verstaerkten Kreislaufwirtschaft. Systemtechnische und oekonomische Modellierung am Beispiel des Stoffstroms 'Papier'

    Energy Technology Data Exchange (ETDEWEB)

    Nathani, C.

    2000-02-01

    The impacts of a long-term change from our present industrial society to an economy based on circular flow concepts approaching the characteristics of the concept of sustainable development have to be taken into account in macroeconomic modelling as well, or else there is no appropriate basis for examination and assessment of the effects of various resource management policy options on the economy. One possible methodological approach is to link single, process-oriented models of sectors of the industry with input-output models and macroeconomic models. This study presents an approach using as an example the pulp and paper industry of Germany, covering the period from 1995 until 2020. The results are found to improve the methodological perspective between the process models and the MIS model of the family of IKARUS models and also offer an additional advantage in that they may serve as a data source for other input-output models and macroeconomic modelling. (orig./CB) [German] Diese Einfluesse eines langfristigen Wandels von einer heutigen Industriegesellschaft zu einer Kreislaufwirtschaft mit Merkmalen einer nachhaltigen Entwicklung muessen sich auch in den Strukturen makrooekonomischer Modelle wiederfinden, um die Auswirkungen verschiedener ressourcenpolitischer Optionen auf die Wirtschaft angemessen pruefen zu koennen. Ein methodischer Weg zu dieser Aufgabe ist die Verknuepfung einzelner prozessorientierter Branchenmodelle mit Input-Output-Modellen und makrooekonomischen Modellen. Der vorliegende Bericht will hierzu einen Baustein am Beispiel der Zellstoff- und Papierindustrie fuer die Bundesrepublik Deutschland fuer die Zeitperiode 1995-2020 beitragen. Diese Ergebnisse verbessern nicht nur die methodische Perspektive zwischen den Prozessmodellen und dem MIS-Modell der IKARUS-Modellfamilie, sondern koennen als Erfahrungs- und Datenquelle fuer andere Input-Output-Modelle und makrooekonomische Modelle genutzt werden. (orig.)

  14. Konzeption und Entwicklung eines echtzeitfähigen Lastgenerators für Multimedia-Verkehrsströme in IP-basierten Rechnernetzen

    Science.gov (United States)

    Kolesnikov, Audrey

    Mit wachsender Komplexität moderner Kommunikations- und Informationssysteme werden entsprechende Leistungsanalysen und Verhaltensprognosen unter verschiedenen Lastszenarien für solche Systeme zunehmend von Bedeutung sein. Der Bedarf nach geeigneten Werkzeugen zur Modellierung und Generierung von Lasten steigt somit auch kontinuietlich. In diesem Beitrag wird ein Entwurf für einen echtzeitfähigen Lastgenerator UniLoG prrisentiert und in Verbindung mit den Adaptern für Lastgenerierung an den Transportdienstsdmittstellen TCP und UDP auf seine Leistungsfahigkeit und Prrizision hin untersucht.

  15. Biofilter odour reduction level, measurements; Luktreduceringsgrad hos biofilter, faeltmaetningar

    Energy Technology Data Exchange (ETDEWEB)

    Arrhenius, Karine; Rosell, Lars; Tsetsilas, Sakis (SP, Boraas (Sweden)); Loevenklev, Maria; Blomqvist, Marie; Hall, Gunnar; Sverken, Anna; Widen, Helene (SIK, Goeteborg (Sweden)); Holmgren, Magnus Andreas (Vattenfall Power Consultants (Sweden))

    2010-07-01

    Biofilter is today the most common odour reduction method for biological treatment. A biofilter consists of a bed of organic material often made of compost together with another material which increases the porosity of the bed. Microorganisms in the compost use odorous compounds as nutrient by decomposing them. Resulting products are mainly carbon dioxide and water, mineral salts, other organic compounds and more microorganisms. In this project, seven biofilters implemented in Sweden have been tested in order to describe their status and function. A number of physical, chemical, microbiological and odour related parameters have be measured in the pipe which leads to the biofilter as well as on the surface of the biofilter in order to determine biofilters status and their effectiveness. Values from plants have been compared to published optimal values for each parameter. The goal of the project is to optimize biofilters function och prevent risks for performance disturbances. Results from the project can also be used as reference for plants which are planning process modifications as an increase of waste to be treated, substrate/material changes etc. Each plant has been visited during two days in August/September 2009. The following parameters have been measured: 1) physical parameters such as relative humidity, temperature, and pH, 2) chemical parameters such as incoming and out coming gas composition, gas composition variation with time, access to nutriments, 3) microbiological parameters such as the total number of microorganisms and the dominating microflora i respective biofilter and 4) odour related parameters through an evaluation of the contribution of individual compounds to the total out coming odour and in some cases, through a evaluation by olfactometry. All these parameters have been subsequently interpreted and treated in order to evaluate the status of the biofilter: description of the biofilter, its environment, the microbiological status, which flow

  16. Quantitative Datenanalyse zur längsschnittlichen Erfassung der Rechtschreibkompetenz in NEPS unter besonderer Berücksichtigung der Kompetenzstruktur und der Einflussfaktoren

    OpenAIRE

    Jarsinski, Stephan

    2014-01-01

    In der methodisch ausgerichteten Arbeit wurde aus einer erziehungswissenschaftlichen Perspektive grundlegenden Fragen zur längsschnittlichen Messung und Modellierung der Rechtschreibkompetenz nachgegangen. Dazu wurden Daten aus dem Nationalen Bildungspanel (National Educational Panel Study, NEPS) genutzt. Die kompetenzorientierte Leistungsmessung erfolgte mit einem sprachsystematischen Rechtschreibtest (SRT). Der SRT basiert auf einem theoretischen Rahmenkonzept, das auf Ergebnissen der lingu...

  17. Sulfide oxidation in a biofilter

    DEFF Research Database (Denmark)

    Pedersen, Claus Lunde; Dezhao, Liu; Hansen, Michael Jørgen;

    Observed hydrogen sulfide uptake rates in a biofilter treating waste air from a pig farm were too high to be explained within conventional limits of sulfide solubility, diffusion in a biofilm and bacterial metabolism. Clone libraries of 16S and 18S rRNA genes from the biofilter found no sulfide o...... higher hydrogen sulfide uptake followed by oxidation catalyzed by iron-containing enzymes such as cytochrome c oxidase in a process uncoupled from energy conservation....

  18. Sulfide oxidation in a biofilter

    DEFF Research Database (Denmark)

    Pedersen, Claus Lunde; Liu, Dezhao; Hansen, Michael Jørgen;

    2012-01-01

    Observed hydrogen sulfide uptake rates in a biofilter treating waste air from a pig farm were too high to be explained within conventional limits of sulfide solubility, diffusion in a biofilm and bacterial metabolism. Clone libraries of 16S and 18S rRNA genes from the biofilter found no sulfide o...... higher hydrogen sulfide uptake followed by oxidation catalyzed by iron-containing enzymes such as cytochrome c oxidase in a process uncoupled from energy conservation....

  19. Lewis-acid and redox-active zeolite catalysts for the activation of methane and lower hydrocarbons in the selective catalytic reduction of NO{sub x}. Subproject: structural characterization and kinetic modelling. Final report; Lewis-acide und redox-aktive Zeolith-Katalysatoren fuer die Aktivierung von Methan und Fluessiggas-Kohlenwasserstoffen in der SCR von NO{sub x}. Teilprojekt: Strukturelle Katalysatorcharakterisierung und Modellierung der Reaktionskinetik. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Gruenert, W. [Bochum Univ. (Germany). Technische Chemie; Sowade, T.; Schmidt, C.; Stroeder, U. [Heraeus (W.C.) GmbH, Hanau (Germany)

    2001-12-01

    SCR of NO by methane was measured for a wide range of concentrations of NO (250-1000 ppm), methane (500-2000 ppm), O{sub 2} (2-10%), and H{sub 2}O (0-10%) and for different GHSV (30 000-90 000 h{sup -1}) and temperatures (between 623 K and 873 K). The data were fitted to a power-law model. Since significant changes of reaction orders occur apparently at very low water concentrations, different models resulted for dry and moist feeds. (orig.) [German] Indium-modifizierte und zusaetzlich mit Ceroxid promotierte Zeolithe (insbesondere ZSM-5) wurden als Katalysatoren fuer die selektive Reduktion von NO mit Methan untersucht. Die strukturellen Eigenschaften der Katalysatoren wurden durch XRD, FTIR, EXAFS, Elektronenmikroskopie und XPS studiert. Der Cerpromotor kann zum Grundsystem In-ZSM-5 durch Faellung auf die aeussere Zeolithoberflaeche zugegeben oder als Ceroxidpulver hoher Oberflaeche beigemischt werden. Die Praeparation des In-ZSM-5 - Grundsystems hat grossen Einfluss auf die katalytischen Eigenschaften. Praeparationen ueber waessrigen Eintausch fuehren meist zu koexistierenden intra- und extra-zeolithischen Indium-Spezies, wobei erstere in geringer Menge gebildet werden. Nur im sauren Bereich sind ausschliesslich intrazeolithische In-Spezies zu erhalten, mit einem maximalen Austauschgrad von 10%. Intra-zeolithisches Indium kann auch durch trockene Praeparationen mit InCl{sub 3} erhalten werden; die sich bildenden Spezies tragen Chlorliganden. Diese Chlorliganden sind je nach In-Konzentration recht stabil; nach Waschen und Kalzinieren konnten sie nur in Proben mit geringem In-Gehalt nicht mehr nachgewiesen werden. Reduktiver Festkoerperionenaustausch in Wasserstoffatmosphaere ist eine weitere Route zur Praeparation intrazeolischen Indiums. In Mischungen mit Indiumueberschuss bilden sich dabei oligomere intrazeolithische Cluster. Intra-zeolithische Cl-freie In-Spezies zeigen SCR-Aktivitaet, waehrend Cl-haltige In-Spezies Methan aktivieren, jedoch geringe Selektivitaet

  20. Effects of climate, land use and changes in these on water availability and high water events in Europe. Projects: Effects of climate change on water availability and high water events in Germany and Europe: An integrated analysis. - Water availability and high water discharge (Elbe and Oder rivers) as a function of climate and land use and changes in these. - Modelling of discharge in the upper section of the Oder river in case of extreme high water events.. Joint final report; Auswirkungen des Klimas und der Landnutzung sowie ihrer Aenderungen auf die Wasserverfuegbarkeit und auf Hochwasserereignisse in Europa. Einzelprojekte: Einfluss des Klimawandels auf Wasserverfuegbarkeit und Hochwasser in Deutschland und Europa: eine integrierte Analyse. - Wasserverfuegbarkeit und Hochwasserabfluss (Elbe- und Odergebiet) in Abhaengigkeit von Klima und Landnutzung und deren Aenderungen. - Modellierung des Abflusses im Oberlauf der Oder fuer Extremereignisse. Gemeinsamer Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Alcamo, J.; Doell, P.; Lehner, B.; Becker, A.; Beckmann, T.; Mengelkamp, H.T.; Sutmoeller, J.

    2001-07-01

    The integrated global water model WaterGAP (macroscale; time step: 1 month) was used for large-scale simulation of the effects of climate change and global change on water availability, high water and low water events and the hydroelectric potential of Germany and Europe, in consideration of long-term scenarios of change. The polygon-based hydrological modelling system ARC/EGMO, with high spatial resolution (mesoscale; time step: 1 day) is used for investigations with high spatial and temporal differentiation of the effects of changes in climate and land use on discharge in river catchment areas of different sizes, i.e. with different degrees of complexity of modelling. The investigations focused on the Elbe and Oder region. The development of high water events as in July 1997 on the upper section of the Oder river is investigated in detail using the complex, high-resolution model system GESIMA/SEWAB/TOPMODEL (mesoscale; time step: 1 hour) [German] Das integrierte globale Wassermodell WaterGAP (makroskalig, Zeitschritt: 1 Monaten) wird zur grossskaligen Simulation der Auswirkungen von Klimaaenderungen und Globalem Wandel auf die Wasserverfuegbarkeit (Wasserdargebot und Wassernutzung), auf die Hoch- und Niedrigwasserhaeufigkeiten und auf das Wasserkraftpotential in Deutschland und Europa unter Verwendung langfristiger Aenderungszenarien eingesetzt. Das raeumlich hochaufloesende, polygonbasiert arbeitende hydrologische Modellierungssystem ARC/EGMO (mesoskalig, Zeitschritt: 1 Tag) wird zur raeumlich und zeitlich differenzierten Untersuchung der Auswirkungen von Klima- und Landnutzungsaenderungen auf das Abflussverhalten in Flussgebieten unterschiedlicher Groesse eingesetzt, wobei der Modellierungsaufwand entsprechend hoeher ist. Im Rahmen des Projektverbunds erfolgt die Anwendung im Elbe- oder Odergebiet. Mithilfe des komplexen, hochaufloesenden Modellsystems GESIMA/SEWAB/TOPMODEL (mesoskalig, Zeitschritt: 1 Stunde und kleiner) wird die Entstehung von Hochwasser

  1. Trimethylamine (TMA) biofiltration and transformation in biofilters.

    Science.gov (United States)

    Ding, Ying; Shi, Ji-Yan; Wu, Wei-Xiang; Yin, Jun; Chen, Ying-Xu

    2007-05-01

    Bioremoval of trimethylamine (TMA) in two three-stage biofilters packed with compost (A) and sludge (B), respectively, was investigated. Both biofilters were operated with an influent TMA concentration of 19.2-57.2mgm(-3) for 67 days. Results showed that all of the inlet TMA could be removed by both biofilters. However, removal efficiency and transformation of TMA in each section of both biofilters was different. In the Introduction section, TMA removal efficiency and maximum elimination capacity of the compost medium were greater than those of sludge medium under higher inlet TMA concentration. In comparison with biofilter A, considerably higher NH(3) concentrations in effluent of all three sections in biofilter B were observed after day 19. Although, NO(2)(-)-N concentration in each section of biofilter A was relatively lower, NO(3)(-)-N content in each section of biofilter A increased after day 26, especially in the Materials and method section which increased remarkably due to a lesser amount of TMA and higher ammonia oxidation and nitrification in compost medium. In contrast, neither NO(2)(-)-N nor NO(3)(-)-N were detected in either section of biofilter B at any time throughout the course of the experiment. The cumulative results indicated that compost is more favorable for the growth of TMA-degrading and nitrifying bacteria as compared to the sludge and could be a highly suitable packing material for biodegradation and transformation of TMA.

  2. Modelling and mapping of spatial differentiated impacts of nitrogen input to ecosystems within the framework of the UNECE-Convention of Air Pollution Prevention. Part I. Simulations of nutrient cycle and leaching form German forest ecosystems considering changes in deposition and climate; Modellierung und Kartierung raeumlich differenzierter Wirkungen von Stickstoffeintraegen in Oekosysteme im Rahmen der UNECE-Luftreinhaltekonvention. Teilbericht I. Simulationen oekosystemarer Stoffumsetzungen und Stoffaustraege aus Waldoekosystemen in Duetschland unter Beruecksichtigung geaenderter Stoffeintraege und Klimabedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Wochele, Sandra; Kiese, Ralf; Butterbach-Bahl, Klaus; Grote, R. [Karlsruhe Institute of Technology (KIT), Garmisch-Partenkirchen (DE). Inst. for Meteorology and Climate Research Atmospheric Environmental Research (IMK-IFU)

    2010-03-15

    nitrogen losses (NO{sub 3}{sup -} und N{sub 2}O). Sensitivity studies regarding different nitrogen deposition scenarios show, that a decline of nitrogen deposition to 15 kg N ha{sup -1} year{sup -1} show a moderate, a decline of nitrogen deposition to 5 kg N ha{sup -1} year{sup -1} show a faster recovery of the forest sites investigated. For assessing impacts of nitrogen deposition on plant biodiversity time series of base saturation, pH value, C/N ratio and water availability provided by the biogeochemical model served as input in two different plant biodiversity models. In dependency of changes in abiotic parameters i.e. soil and climate the biodiversity model BERN (Bioindication for Ecosystem Regeneration towards Natural conditions, OeKO-DATA) and the model of the Waldkunde Institute Eberswalde (W.I.E.) are able to predict future vegetation development based on extensive empirical data collection and derived statistical relations. Based on the coupled simulations of the biogeochemical Forest-DNDC-SAFE model and the biodiversity model predictions concerning the endangerment of vegetation diversity can be assessed and hence Critical Loads for nitrogen can be derived. A new aspect of this project is that not only predictions on the endangerment of plant biodiversity but also about other subjects of protection like the atmosphere and the hydrosphere can be made. This is of great importance, since simulations show that depending on specific site conditions higher N losses via N{sub 2}O or nitrate leaching partly anti-correlate with a narrowing of the soil C/N ratio i.e. increased N availability, resulting in different impacts on the subjects of protection atmosphere, hydrosphere and biodiversity. In addition to the biogeochemical induced impacts on plant biodiversity, in the near future also impacts of climate change (increase of drought stress, extension of the vegetation period), on the species composition in terrestrial ecosystems have to be accounted for. The climate

  3. Modelling and mapping of spatial differentiated impacts of nitrogen input to ecosystems within the framework of the UNECE-Convention of Air Pollution Prevention. Part I. Simulations of nutrient cycle and leaching form German forest ecosystems considering changes in deposition and climate; Modellierung und Kartierung raeumlich differenzierter Wirkungen von Stickstoffeintraegen in Oekosysteme im Rahmen der UNECE-Luftreinhaltekonvention. Teilbericht I. Simulationen oekosystemarer Stoffumsetzungen und Stoffaustraege aus Waldoekosystemen in Duetschland unter Beruecksichtigung geaenderter Stoffeintraege und Klimabedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Wochele, Sandra; Kiese, Ralf; Butterbach-Bahl, Klaus; Grote, R. [Karlsruhe Institute of Technology (KIT), Garmisch-Partenkirchen (DE). Inst. for Meteorology and Climate Research Atmospheric Environmental Research (IMK-IFU)

    2010-03-15

    nitrogen losses (NO{sub 3}{sup -} und N{sub 2}O). Sensitivity studies regarding different nitrogen deposition scenarios show, that a decline of nitrogen deposition to 15 kg N ha{sup -1} year{sup -1} show a moderate, a decline of nitrogen deposition to 5 kg N ha{sup -1} year{sup -1} show a faster recovery of the forest sites investigated. For assessing impacts of nitrogen deposition on plant biodiversity time series of base saturation, pH value, C/N ratio and water availability provided by the biogeochemical model served as input in two different plant biodiversity models. In dependency of changes in abiotic parameters i.e. soil and climate the biodiversity model BERN (Bioindication for Ecosystem Regeneration towards Natural conditions, OeKO-DATA) and the model of the Waldkunde Institute Eberswalde (W.I.E.) are able to predict future vegetation development based on extensive empirical data collection and derived statistical relations. Based on the coupled simulations of the biogeochemical Forest-DNDC-SAFE model and the biodiversity model predictions concerning the endangerment of vegetation diversity can be assessed and hence Critical Loads for nitrogen can be derived. A new aspect of this project is that not only predictions on the endangerment of plant biodiversity but also about other subjects of protection like the atmosphere and the hydrosphere can be made. This is of great importance, since simulations show that depending on specific site conditions higher N losses via N{sub 2}O or nitrate leaching partly anti-correlate with a narrowing of the soil C/N ratio i.e. increased N availability, resulting in different impacts on the subjects of protection atmosphere, hydrosphere and biodiversity. In addition to the biogeochemical induced impacts on plant biodiversity, in the near future also impacts of climate change (increase of drought stress, extension of the vegetation period), on the species composition in terrestrial ecosystems have to be accounted for. The climate

  4. Simulation, evaluation and optimization of hydrological storage systems; Simulation, Bewertung und Optimierung von Betriebsregeln fuer wasserwirtschaftliche Speichersysteme

    Energy Technology Data Exchange (ETDEWEB)

    Lohr, H.

    2001-07-01

    The investigation focused on controlled hydrological storage system. Existing operating schedules and new control options were analyzed, classified and generalized in order to obtain a standardized terminology and operating concept. This generalized approach will do away with the need for system-specific analyses and models for every single new system. [German] Der Schwerpunkt dieser Arbeit ist der wasserwirtschaftliche Betrieb von regelbaren Speichersystemen und ihre Simulation. Dabei bestand das Ziel darin, bestehende Betriebsplaene und neue praktikable Steuerungsmoeglichkeiten zu analysieren, zu klassifizieren und so zu generalisieren, dass eine einheitliche Terminologie und Konzeption zum Betrieb von Speichern entstand. Dieses Konzept erlaubt, in Verbindung mit den Prinzipien aus der Modellierung von Flussgebieten, verschieden strukturierte Speichersysteme mit unterschiedlichsten Steuerungsvorschriften abzubilden. Damit erhaelt man den Vorteil einer generalisierten Anwendung im Gegensatz zu einer fuer den speziellen Fall konzipierten und nicht uebertragbaren Einzelloesung. Als Folge davon entfaellt das systemspezifische, je nach Aufgabenstellung neu zu entwerfende und zu programmierende Einzelmodell. (orig.)

  5. INDUSTRIAL GAS PURIFICATION USE OF BIOFILTERS

    Directory of Open Access Journals (Sweden)

    Irina Ramona PECINGINĂ

    2012-05-01

    Full Text Available Biological filtration systems is one of the current alternatives to remove residual volatile components of the air through biological means, without affecting the natural environment. Biofilters have a technology that uses microorganisms (bacteria to treat emissions, in a secure economic and environmental quality. Biofilters consist of porous filters, which is distributed flue gas stream

  6. The Barrien natural gas deposit. Status, results and outlook of an interdisciplinary reservoir study; Die Erdgaslagerstaette Barrien. Status, Ergebnisse und Ausblick einer interdisziplinaeren Reservoirstudie

    Energy Technology Data Exchange (ETDEWEB)

    Baerle, C.; Beuthan, H. [Wintershall AG Erdoelwerke, Barnstorf (Germany); Weihe, T. [Wintershall AG, Kassel (Germany)

    1999-07-01

    Geological and geophysical investigation and modelling of the Detfurth series of the Barrien natural gas deposit provided new and detailed information on the reservoir horizon. Seismic reinterpretation yielded new findings especially on the crest region of the structure and verified the complex fault model. Core profiles, facial analysis and log correlation demonstrate the lateral distribution and horizontal variability of the sedimentary units and thus of the petrophysical characteristics (porosity, permeability). Petrographic investigations provided detailed, production-relevant information on sandstone cementation and pore space characteristics. The results were integrated in the geological models together with the known deposit parameters. [German] Die geologische-geophysikalische Bearbeitung und Modellierung der Detfurth-Folge in der Gaslagerstaette Barrien erbrachte neue und z.T. detailliertere Informationen ueber die Ausbildung der Traegerhorizontale. Die Reinterpretation der Seismik liefert hauptsaechlich im Scheitelbereich der Struktur neue Erkenntnisse und verifiziert das komplexe Stoerungsmodell. Die Kernaufnahme, fazielle Einstufung und Logkorrelation demonstriert die laterale Verbreitung sowie horizontale Variabilitaet der sedimentaeren Einheiten und damit der petrophysikalischen Werte (Porositaet, Permeabilitaet). Die petrographischen Untersuchungen erbrachten detaillierte und produktionsrelevante Informationen zur Sandsteinzementation und der Porenraumbeschaffenheit. Zusammen mit den bekannten Lagerstaettenparametern wurden diese Ergebnisse in die geologische Modellierung integriert. (orig.)

  7. Biodegradation of methanol vapor in a biofilter

    Institute of Scientific and Technical Information of China (English)

    Durai Arulneyam; T. Swaminathan

    2003-01-01

    Volatile organic compounds (VOCs) are a new class of air pollutants posing threat to the environment. Newer technologies are being developed for their control among which biofiltration seem to be most attractive. Biofiltration of methanol vapor from air stream was evaluated in this study. Experimental investigations were conducted on a laboratory scale biofilter, containing mixture of compost and polystyrene inert particles as the filter materials. Mixed consortium of activated sludge was used as an inoculum. The continuous performance of biofilter for methanol removal was monitored for different concentrations and flow rates. The removal efficiencies decreased at higher concentrations and higher gas flow rates. A maximum elimination capacity of 85 g/(m3.h) was achieved. The response of biofilter to upset loading operation showed that the biofilm in the biofilters was quite stable and quickly adapted to adverse operational conditions.

  8. Survival of Escherichia coli in stormwater biofilters.

    Science.gov (United States)

    Chandrasena, G I; Deletic, A; McCarthy, D T

    2014-04-01

    Biofilters are widely adopted in Australia for stormwater treatment, but the reported removal of common faecal indicators (such as Escherichia coli (E. coli)) varies from net removal to net leaching. Currently, the underlying mechanisms that govern the faecal microbial removal in the biofilters are poorly understood. Therefore, it is important to study retention and subsequent survival of faecal microorganisms in the biofilters under different biofilter designs and operational characteristics. The current study investigates how E. coli survival is influenced by temperature, moisture content, sunlight exposure and presence of other microorganisms in filter media and top surface sediment. Soil samples were taken from two different biofilters to investigate E. coli survival under controlled laboratory conditions. Results revealed that the presence of other microorganisms and temperature are vital stressors which govern the survival of E. coli captured either in the top surface sediment or filter media, while sunlight exposure and moisture content are important for the survival of E. coli captured in the top surface sediment compared to that of the filter media. Moreover, increased survival was found in the filter media compared to the top sediment, and sand filter media was found be more hostile than loamy sand filter media towards E. coli survival. Results also suggest that the contribution from the tested environmental stressors on E. coli survival in biofilters will be greatly affected by the seasonality and may vary from one site to another.

  9. Autotrophic Biofilters for Oxidation of Nitric Oxide

    Institute of Scientific and Technical Information of China (English)

    陈建孟; 陈浚; LanceHershman; 王家德; DanielP.Y.Chang

    2004-01-01

    Carbon foam—a kind of new engineering material as packing material was adopted in three biofilters with different pore dimensions and adapted autotrophic nitrite nitrobacteria to investigate the purification of nitric oxide (NO) in a gas stream. The biofilm was developed on the surface of carbon foams using nitrite as its only nitric source. The moisture in the filter was maintained by ultrasonic aerosol equipment which can minimize the thickness of the liquid film. The liquid phase nitrification test was conducted to determine the variability and the potential of performance among the three carbon foam biofilters. The investigation showed that during the NO2-—N inlet concentration of 200 g·L-1·min-1 to 800 g·L-1·min-1, the 24PPC (pores per centimeter) carbon foam biofilter had the greatest potential, achieving the NO2-—N removal efficiency of 94% to 98%. The 8PPC and 18PPC carbon foam biofilters achieved the NO2-—N removal efficiency of 15% to 21% and of 30% to 40%, respectively. The potential for this system to remove NO from a gas stream was shown on the basis of a steady removal efficiency of 41% to 50% which was attained for the 24PPC carbon foam biofilter at specified NO inlet concentration of 66.97 mg·m-3 to 267.86mg·m-3 and an empty-bed residence time of 3.5 min.

  10. Terahertz Spektroskopie und Simulation wässriger Lösungen : Hydrophobizität, Faltung, Ladungen und Phasenübergänge in Wasserstoffbrückennetzwerken

    OpenAIRE

    Niehues, Gudrun

    2011-01-01

    Die Untersuchung wässriger Lösungen mittels THz Spektroskopie und deren Modellierung mit Hilfe von MD Simulationen wird beschrieben. Mit Hilfe von "Driven Molecular Dynamics" Simulationen wird ein effektiver Energieübertrag vom angeregten Molekül auf das umgebende Solvens bei THz Anregung im Vergleich zur IR Anregung gezeigt. Optimierungen an einem p-Ge Laser System zur präzise Bestimmung des konzentrationsabhängigen THz Absorptionskoeffizienten (2.2-2.8 THz) werden vorgestellt. B...

  11. Optimal operation of complex maritime and stationary power plants. Proceedings; Optimaler Betrieb komplexer maritimer und stationaerer Energieanlagen. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    An expert colloquium was held on problems concerning the optimal operation of maritime and stationary power plants. The present report contains the full text of the four lectures held: Novel methods of process analysis and modelling of complex energy systems; methods for assessing regional energy systems; creation of a model for optimising the operation of the system of engine-propeller-ship; diagnosis system for large diesel engines. Each of the four lectures has been abstracted individually. (HW) [Deutsch] In einem Fachkolloquim wird ueber Probleme eines optimalen Betriebes maritimer und stationaerer Energieanlagen diskutiert. Im vorliegenden Bericht sind die Fassungen der 4 Referate abgedruckt: 1. Neuartige Methoden der Prozessanalyse und -Modellierung komplexer energetischer Systeme 2. Methode zur Bewertung regionaler Energiesysteme 3. Modellbildung und Betriebsoptimierung des Systems Motor-Propeller-Schiff 4. Diagnosesystem fuer Grossdieselmotoren. Fuer alle 4 Referate wurde eine gesonderte inhaltliche Erschliessung erstellt. (HW)

  12. Surrogates for herbicide removal in stormwater biofilters.

    Science.gov (United States)

    Zhang, Kefeng; Deletic, Ana; Page, Declan; McCarthy, David T

    2015-09-15

    Real time monitoring of suitable surrogate parameters are critical to the validation of any water treatment processes, and is of particularly high importance for validation of natural stormwater treatment systems. In this study, potential surrogates for herbicide removal in stormwater biofilters (also known as stormwater bio-retention or rain-gardens) were assessed using field challenge tests and matched laboratory column experiments. Differential UV absorbance at 254mn (ΔUVA254), total phosphorus (ΔTP), dissolved phosphorus (ΔDP), total nitrogen (ΔTN), ammonia (ΔNH3), nitrate and nitrite (ΔNO3+NO2), dissolved organic carbon (ΔDOC) and total suspended solids (ΔTSS) were compared with glyphosate, atrazine, simazine and prometryn removal rates. The influence of different challenge conditions on the performance of each surrogate was studied. Differential TP was significantly and linearly related to glyphosate reduction (R(2) = 0.75-0.98, P biofilters.

  13. A comparative study in treating two VOC mixtures in trickle bed air biofilters.

    Science.gov (United States)

    Cai, Zhangli; Kim, Daekeun; Sorial, George A

    2007-06-01

    Two independent parallel trickling bed air biofilters (TBABs) ("A" and "B") with two different typical VOC mixtures were investigated. Toluene, styrene, methyl ethyl ketone (MEK), and methyl isobutyl ketone (MIBK) were the target VOCs in the mixtures. Biofilter "A" was fed equal molar ratio of the VOCs and biofilter "B" was fed a mixture based on EPA 2003 emission report. Backwashing and substrate starvation operation were conducted as biomass control. Biofilter "A" and "B" maintained 99% overall removal efficiency for influent concentration up to 500 and 300 ppmv under backwashing operating condition, respectively. The starvation study indicated that it can be an effective biomass control for influent concentrations up to 250 ppmv for biofilter "A" and 300 ppmv for "B". Re-acclimation of biofilter performance was delayed with increase of influent concentration for both biofilters. Starvation operation helped the biofilter to recover at low concentrations and delayed re-acclimation at high concentrations. Furthermore, re-acclamation for biofilter "B" was delayed due to its high toluene content as compared to biofilter "A". The pseudo first-order removal rate constant decreased with increase of volumetric loading rate for both biofilters. MEK and MIBK were completely removed in the upper 3/8 media depth. While biofilter depth utilization for the removal of styrene and toluene increased with increase of influent concentrations for both biofilters. However, toluene removal utilized more biofilter depth for biofilter "B" as compared to biofilter "A".

  14. Nitrification performance and robustness of fixed and moving bed biofilters having identical carrier elements

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming; Oosterveld, Remko; Pedersen, Per Bovbjerg

    2015-01-01

    This study compared moving bed (MB) and fixed bed (FB) biofilter performance. The experimental recir-culating aquaculture system had four equal biofilters in parallel. Each of the two replicated FB biofilters(with heavy elements) and the two MB biofilters (with neutral elements) had 200 l carrier...

  15. Design and management of conventional fluidized-sand biofilters

    Science.gov (United States)

    Fluidized sand biofilters (FSBs) are relatively compact, efficient, and cost-competitive biofilters, especially in recirculating systems that require maintaining consistently low levels of ammonia and nitrite. Filter sand is low cost (often $70-200/m3 of sand delivered) and has a high specific surf...

  16. X-ray microtomography, ultrasound and thermography for the characterization of defects in fiberglass and carbon fiber composite materials and elements; Roentgen-Mikrotomografie, Ultraschall und Thermographie fuer die Charakterisierung von Defekten in GFK- und CFK-Verbundwerkstoffen und -Elementen

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, Andreas J.; Jerjen, Iwan; Plamondon, Mathieu; Furrer, Roman; Neuenschwander, Juerg [EMPA Eidgenoessische Materialpruefungs- und Forschungsanstalt, Duebendorf (Switzerland)

    2015-07-01

    Glass and carbon fiber reinforced plastics (GRP or CFRP composites) may have different defects that arise on the one hand in the manufacturing process and on the other hand occur or propagate under quasi-static or oscillating mechanical load. The characterization of the nature, location and size of defects is important among other things for optimization of manufacturing processes, modeling of material or component behavior and for the estimation of the useful life of components or structures from GFK or CFK composites. The contribution shows selected examples of the application of X-ray microtomography, ultrasound and thermography for the characterization of defects in fiberglass or carbon fiber composite components. In ''thick'' laminates and complex shapes the X-ray method is particularly suitable. [German] Glas- und Kohlenstoff-faserverstaerkte Kunststoffe (GFK- bzw. CFK-Verbundwerkstoffe) koennen unterschiedliche Defekte ausweisen, die einerseits im Herstellungsprozess entstehen und sich andererseits bei der Nutzung unter quasistatischer oder schwingender mechanischer Belastung ausbilden oder sich ausbreiten. Die Charakterisierung der Art, der Lage und der Groesse der Defekte ist u.a. fuer Optimierung der Herstellungsprozesse, Modellierung des Werkstoff- oder Bauteilverhaltens sowie der Abschaetzung der Nutzungsdauer von Komponenten oder Strukturen aus GFK- oder CFK-Verbundwerkstoffen wichtig. Der Beitrag zeigt ausgewaehlte Beispiele der Anwendung von Roentgen-Mikrotomografie, Ultraschall und Thermographie zur Charakterisierung von Defekten in GFK- oder CFK-Verbundwerkstoff-Bauteilen. Bei ''dicken'' Laminaten und komplexen Geometrien ist das Roentgenverfahren besonders geeignet.

  17. Chemical composition and optical properties of aerosols in the lower mixed layer and the free troposphere. Final report of the AFS project; Chemische Zusammensetzung und optische Eigenschaften des Aerosols in der freien Troposphaere. Abschlussbericht zum AFS-Projekt

    Energy Technology Data Exchange (ETDEWEB)

    Asseng, H. [Freie Univ. Berlin (Germany). Inst. fuer Weltraumwissenschaften]|[Max-Planck-Institut fuer Chemie, Mainz (Germany). Abt. Biogeochemie; Fischer, J. [Freie Univ. Berlin (Germany). Inst. fuer Weltraumwissenschaften; Helas, G. [Max-Planck-Institut fuer Chemie, Mainz (Germany). Abt. Biogeochemie; Weller, M. [Deutscher Wetterdienst, Potsdam (Germany). Meteorologisches Observatorium

    2001-08-02

    Aerosol radiative forcing is the largest unknown in current climate models and, as a result, in predicting future climate. Accurate vertically-resolved measurements of aerosol optical properties are an important element of improved climate prediction (IPCC). The present project has contributed to this objective. Jets of directly and remotely determined radiation data have been provided suitable to cut down the uncertainty of column- or layer related optical aerosol parameters. In the present case mean values and profiles of spectral scattering - and absorption coefficients have been retrieved from ground based and airborne sky-radiance/solar irradiance measurements. Available analyses of size and chemical composition of sampled particles (adjoined projects) have been also taken into consideration. The retrieved parameters have served as an input for modelling the radiative transfer exactly for the real time of measurements. Closure procedures yielded finally realistic spectral scattering - and absorption coefficients typically for the lower troposphere in a mostly rural Central European region. (orig.) [German] Die ungenuegende Kenntnis strahlungswirksamer, optischer Aerosolparameter ist laut IPCC die groesste Unbekannte bei der Modellierung des Klimas und seiner Veraenderung. Wissenschaft und Technik bemuehen sich in sog. Schliessungsexperimenten aus der Ueberbestimmung direkt und indirekt gemessener Aerosolparameter genaue(re) Kenntnis (Mittelwert/Variation) ueber deren Klimawirksamkeit zu erlangen. Im vorliegenden Projekt wurden aus verschiedenen passiven, spektralen Messungen von Streulicht und Transmission der Atmosphaere in verschiedenen Hoehen sowie aus der Beruecksichtigung von Partikelanalysen Dritter, Streu- und Absorptionskoeffizienten des Aerosols der gesamten Luftsaeule und in vertikaler Aufloesung abgeleitet. Strahlungstransportmodellierungen mit den gewonnenen Aerosolparametern als input engten ueber den Vergleich mit den Messungen deren Grad an

  18. Integration of seismic reflection and geologically balanced profiles; Integration reflexionsseismischer und geologisch bilanzierter Profile

    Energy Technology Data Exchange (ETDEWEB)

    Lambrecht, A. [Trappe Erdoel Erdgas Consultant, Isernhagen (Germany)

    1998-12-31

    Geophysics and geology employ different kinds of techniques in order to preserve the underground structure. These techniques are based on different sets of data, i.e. seismic or geological data. A sensible combination of the two techniques should produce a better model of the ground structure. This study attempts to integrate geologically balanced profiles and seismic reflection data. A balanced geological profile can than be compared with seismic reflection data measured in the field. The geological model is then changed into a seismic model of the underground by means of seismic modeling. Synthetic modeling is based on the acquisition of available field data. The synthetic stack section or the synthetic migration image are then compared to the field data. Deviations between the two can be attributed to speed errors and the fact that balances will never give an unequivocal solution but always present a group of solutions. (orig. MSK). [Deutsch] In der Geophysik und der Geologie werden verschiedene Techniken verwendet, um die Untergrundstruktur zu erhalten. Diese Techniken basieren auf verschiedenen Datensaetzen, z.B. seismische und geologische Daten. Eine sinnvolle Kombination der Techniken sollte ein besseres Abbild des Untergrundes liefern. In dieser Studie wird ein Versuch unternommen geologisch bilanzierte Profile und reflexionsseismische Daten zu integrieren. Soll ein bilanziertes geologisches Profil mit im Feld gemessenen reflexionsseismischen Daten verglichen werden, dann wird das geologische Modell mit Hilfe der seismischen Modellierung in ein seismisches Abbild des Untergrundes verwandelt. Dabei wird die synthetische Modellierung entsprechend der Aquisition der vorliegenden Felddaten durchgefuehrt. Die synthetische Stapelsektion oder das synthetische Migrationsimage werden anschliessend mit den Felddaten verglichen. Abweichungen zwischen beobachteten und Felddaten haben ihre Ursachen sowohl in Geschwindigkeitsfehlern, als auch in der Tatsache, dass eine

  19. Dolomite limits acidification of a biofilter degrading dimethyl sulphide

    Science.gov (United States)

    Smet; Van Langenhove H; Philips

    1999-01-01

    The applicability of dolomite particles to control acidification in a Hyphomicrobium MS3 inoculated biofilter removing dimethyl sulphide (Me2S) was studied. While direct inoculation of the dolomite particles with the liquid microbial culture was not successful, start-up of Me2S-degradation in the biofilter was observed when the dolomite particles were mixed with 33% (wt/wt) of Hyphomicrobium MS3-inoculated compost or wood bark material. Under optimal conditions, an elimination capacity (EC) of 1680 g Me2S m(-3) d(-1) was obtained for the compost/dolomite biofilter. Contrary to a wood bark or compost biofilter, no reduction in activity due to acidification was observed in these biofilters over a 235 day period because of the micro environment neutralisation of the microbial metabolite H2SO4 with the carbonate in the dolomite material. However, performance of the biofilter decreased when the moisture content of the mixed compost/dolomite material dropped below 15%. Next to this, nutrient limitation resulted in a gradual decrease of the EC and supplementation of a nitrogen source was a prerequisite to obtain a long-term high EC (> 250 g Me2S m(-3) d(-1)) for Me2S. In relation to this nitrogen supplementation, it was observed that stable ECs for Me2S were obtained when this nutrient was dosed to the biofilter at a Me2S-C/NH4Cl-N ratio of about 10.

  20. Biomass and microbial activity in a biofilter during backwashing

    Institute of Scientific and Technical Information of China (English)

    BAI Yu; ZHANG Jie; LI Yi-fan; GAO Yu-nan; LI Yong

    2005-01-01

    Biomass and microbial activity in backwashing processes of a biofilter for tertiary treatment were investigated. The microbial groups revealed new distribution along the biofilter depth after low flow rate backwashing for a short time. Then the start-up process was accelerated by backwashing. The biomass profile and microbial activity profile both varying with depth before and after backwashing, can be mathematically described by quadratic equations. Using the profiles, the difference of oxygen demand can be calculated to determine the airflow rate during backwashing. Combined with the difference between biofilters and rapid gravity filters, analysis of biomass and microbial activity can determine more accurately the required airflow rate during backwashing.

  1. Performance and Biofilm Activity of Nitrifying Biofilters Removing Trihalomethanes

    Science.gov (United States)

    Nitrifying biofilters seeded with three different mixed-culture sources degraded trichloromethane (TCM) and dibromochloromethane (DBCM). In addition, resuspended biofilm degraded TCM, bromododichloromethane (BDCM), DBCM, and tribromomethane (TBM) in backwash batch kinetic tests,...

  2. Simulation of Biomass Accumulation Pattern in Vapor-Phase Biofilters.

    Science.gov (United States)

    Xi, Jin-Ying; Hu, Hong-Ying; Zhang, Xian

    2012-06-01

    Existence of inert biomass and its impact on biomass accumulation patterns and biofilter performance were investigated. Four biofilters were set up in parallel to treat gaseous toluene. Each biofilter operated under different inlet toluene loadings for 100 days. Two microbial growth models, one with an inert biomass assumption and the other without, were established and compared. Results from the model with the inert biomass assumption showed better agreement with the experimental data than those based on the model without the inert biomass assumption thus verifying that inert biomass accumulation cannot be ignored in the long-term operation of biofilters. According to the model with an inert biomass assumption, the ratio of active biomass to total biomass will decrease and the inert biomass will become dominant in total biomass after a period of time. Filter bed structure simulation results showed that the void fraction is more sensitive to biomass accumulation than the specific surface area. The final void fraction of the biofilters with the highest inlet toluene loading is only 67% of its initial level while the final specific surface area is 82%. Identification and quantification of inert biomass will give a better understanding of biomass accumulation in biofilters and will result in a more exact simulation of biomass change during long-term operations. Results also indicate that an ideal biomass control technique should be able to remove most inert biomass while simultaneously preserving as much active biomass as possible.

  3. Ammonia-Oxidizing Bacteria in Biofilters Removing Trihalomethanes Are Related to Nitrosomonas oligotropha

    Science.gov (United States)

    Nitrifying biofilters degrading the four regulated trihalomethanes (THMs) trichloromethane (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and tribromomethane (TBM) -were analyzed for the presence and activity of ammonia-oxidizing bacteria (AOB). Biofilter perfor...

  4. Schattenwirtschaft und Arbeitsplatzbeschaffung

    OpenAIRE

    Merz, Joachim

    1996-01-01

    Ziel dieser Studie ist die empirisch fundierte Auseinandersetzung mit dem Thema Schattenwirtschaft und Arbeitsplatzschaffung. Die hier aufgefächerte Diskussion des Themas in Wirtschaft, Sozialpolitik und Gesellschaft, der weitere Diskurs und die empirische Fundierung erfordern eine klare und dann folgende begriffliche Abgrenzung der Schattenwirtschaft. Argumente der Diskussion zu Ursachen und positiven und negativen Wirkungen der Schattenwirtschaft auf die Arbeitsplatzbeschaffung werden im An...

  5. Eine präzise Multilevel-Testbench zur Systemsimulation und Charakterisierung einer 2,5 GHz PLL

    Directory of Open Access Journals (Sweden)

    I. Kebaisy

    2007-06-01

    Full Text Available In diesem Aufsatz wird eine präzise Multilevel-Testbench zur PLL-Charakterisierung vorgestellt. Die Schwerpunkte dieses Beitrags sind einerseits das 10 GHz VCO-Design und andererseits die vorhersagefähigen Ergebnisse der mit Hilfe dieses Multilevelansatzes durchgeführten PLL-Systemsimulationen.

    Bei dem VCO-Design wurden folgende Ergebnisse erreicht: Abstimmbereich ≈26% bzw. kvco≈1300 MHz/V, Phasenrauschen PN=–101,4 dBc/Hz @1 MHz Offset vom 10 GHz Träger, Leistungsverbrauch = 5,5 mW. Als realistisches Demonstrationsbeispiel ist das „analog mixed signal“-Verhalten eines 2,5 GHz PLL-Systems für „dual-conversion“-Strukturen bei IEEE 802.11a WLAN-Anwendungen gewählt worden. Für dieses Beispiel wird eine effiziente PLL-Modellierung kritischer PLL-Blöcke (Frequenzteiler und Phasenfrequenzdetektor auf der Basis der PSS-Analyse und neuer Verilog-A/MS Befehle demonstriert. Die dabei verwendete Testbench kann im Prinzip in verschiedenen aktuellen Wireless Kommunikationssystemen bis 10 GHz wieder verwendet werden (Reuse-IP. Dieser Ansatz führt einerseits zur Verbesserung der Simulationszeiten (verglichen mit dem Transistorlevel und andererseits zu genaueren und realistischeren Ergebnissen, vor allem am VCO-Ausgang (verglichen mit dem HDL-Level.

  6. Treatment of separated piggery anaerobic digestate liquid using woodchip biofilters.

    Science.gov (United States)

    Carney, K N; Rodgers, M; Lawlor, P G; Zhan, X

    2013-01-01

    The Irish nitrates directive restricts the land area suitable for landspreading of pig manure, so anaerobic digestion warrants consideration. In this study, six identical Lodgepole pine woodchip biofilters were set up to treat the separated liquid fraction of digestate after anaerobic digestion of pig manure. Two hydraulic loading rates were examined: 5 L/m2/d (LLR) and 10 L/m2/d (HLR). Following a start-up period of 70 days, an average of 90% and 71% of NH4(+)-N was removed at LLR and HLR, respectively. LLR resulted in higher total nitrogen removals than HLR (p biofilter effluent. A batch experiment testing the capacity of saturated woodchips in removing total oxidized nitrogen (TON) from the effluent of the woodchip biofilters showed that TON was reduced by 323 mg/L from 663 mg/L in 360 h, indicating that the aerobic woodchip biofilters should incorporate a saturated layer ofwoodchips at the base ofthe biofilters to enhance nitrogen removal.

  7. Gradient packing bed bio-filter for landfill methane mitigation.

    Science.gov (United States)

    Obulisamy, Parthiba Karthikeyan; Sim Yan May, Jane; Rajasekar, Balasubramanian

    2016-10-01

    We assessed the suitability of various biogenic materials for development of a gradient packed bed bio-filter to mitigate the methane (CH4) emission from landfills. Five different biogenic materials (windrow compost-WC; vermicompost-VC; landfill top cover-LTC; landfill bottom soil-LBS; and river soil sediment-SS) were screened. Among these materials, the VC showed a better CH4 oxidation potential (MOP) of 12.6μg CH4 gdw(-1)h(-1). Subsequently, the VC was used as a packing material along with wood chips in proto-type bio-filters. Wood chips were mixed at 5-15% to form three distinct gradients in a test bio-filter. Under the three different CH4 loading rates of 33, 44 and 55 gCH4 m(-3)h(-1), the achieved MOPs were 31, 41, and 47gCH4 m(-3)h(-1), respectively. The gradient packed bed bio-filter is effective for landfill CH4 mitigation than the conventional bio-filter as the latter shows gas channeling effects with poor MOPs.

  8. Particle Reduction Strategies - PAREST. Traffic emission modelling. Model comparision and alternative scenarios. Sub-report; Strategien zur Verminderung der Feinstaubbelastung - PAREST. Verkehrsemissionsmodellierung. Modellvergleich und Alternative Szenarien. Teilbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kugler, Ulrike; Theloke, Jochen [Stuttgart Univ. (Germany). Inst. fuer Energiewirtschaft und Rationelle Energieanwendung (IER); Joerss, Wolfram [Institut fuer Zukunftsstudien und Technologiebewertung gGmbH (IZT), Berlin (Germany)

    2013-06-15

    The modeling of the reference scenario and the various reduction scenarios in PAREST was based on the Central System of Emissions (CSE) (CSE, 2007). Emissions from road traffic were calculated by using the traffic emission model TREMOD (Knoerr et al., 2005) and fed into the CSE. The version TREMOD 4.17 has been used. The resulting emission levels in PAREST reference scenario were supplemented by the emission-reducing effect of the implementation of the future Euro 5 and 6 emission standards for cars and light commercial vehicles and Euro VI for heavy commercial vehicles in combination with the truck toll extension. [German] Die Modellierung des Referenzszenarios und der verschiedenen Minderungsszenarien in PAREST erfolgte auf Grundlage des Zentralen System Emissionen (ZSE) (ZSE, 2007). Emissionen aus dem Strassenverkehr wurden mit Hilfe des Verkehrsemissionsmodells TREMOD (Knoerr et al., 2005) berechnet und in das ZSE eingespeist. Dabei wurde die Version TREMOD 4.17 verwendet. Die daraus resultierenden Emissionsmengen wurden im PAREST-Referenzszenario um die emissionsmindernde Wirkung der zukuenftigen Implementierung der Abgasnormen Euro 5 und 6 fuer Pkw und leichte Nutzfahrzeuge sowie Euro VI fuer schwere Nutzfahrzeuge in Kombination einer Erweiterung der Lkw-Maut ergaenzt. Die Berechnung der Emissionen des Referenzszenarios wurde auf Grundlage des Inlandsprinzips sowie des Energiebilanzprinzips durchgefuehrt. Die auf dieser Grundlage berechneten Emissionen fuer das Basisjahr 2005 und fuer die Referenzjahre 2010, 2015 und 2020 unterscheiden sich teilweise erheblich von den mit Hilfe des Modells TREMOVE (dem von der EU Kommission verwendeten Modell fuer mobile Quellen) berechneten Emissionen.

  9. ANALISIS FISIS MEMBRAN BIOFILTER ROKOK DENGAN VARIASI DAUN, BIJI DAN KULIT DELIMA

    Directory of Open Access Journals (Sweden)

    Umaiyatus Syarifah

    2015-04-01

    Full Text Available Analisis fisis membrane biofilter rokok telah dilakukan untuk mengetahui kerapatan dan porositas. Membrane biofilter terbuat dari variasi daun delima, biji delima dan kulit delima. Variasi massa yang digunakan pada masing-masing bahan delima adalah 0.7 gram, 0.8 gram, 0.9 gram dan 1 gram. Matriks yang digunakan pada pembuatan biofilter berbahan delima adalah polyethilene glikol (PEG. Data pengujian kerapatan membran pada biofilter berbahan daun delima terbesar adalah 1.532 g/cm3 dengan komposisi 0.7 gram. Pada biofilter yang menggunakan biji delima kerapatan paling tinggi bernilai 1.491 g/cm3 dengan komposisi 0.7 gram. Biofilter yang menggunakan kulit delima memiliki kerapatan terbesar pada komposisi 1 gram dengan nilai 1,436 g/cm3. Nilai kerapatan tertinggi antara membran biofilter berbahan daun delima, biji delima dan kulit delima adalah membran biofilter daun delima dengan variasi 0.7 gram. Porositas pada daun delima memiliki nilai terkecil pada variasi massa 0.7 gram dengan nilai porositas 8.67%. pada biji delima porositas terkecil adalah 4.10% dengan variasi massa 0.7 gram. Membran biofilter dengan kulit delima memiliki porositas terkecil pada variasi massa 0.7 gram dengan nilai 76.72%. Nilai porositas terkecil antara membran biofilter berbahan daun delima, biji delima dan kulit delima adalah membran biofilter biji delima dengan variasi 0.7 gram.

  10. Reverse-flow strategy in biofilters treating CS₂ emissions.

    Science.gov (United States)

    Rojo, Naiara; Gallastegui, Gorka; Gurtubay, Luis; Barona, Astrid; Elías, Ana

    2013-04-01

    The bacteriostatic properties of carbon disulphide (CS₂) hamper its biodegradation in conventional biofilters. The response of four biofilters operating in downflow mode and reverse-flow mode was compared in a laboratory-scale plant treating CS₂ under sudden short-term changes in operating conditions. A process shutdown for 24 h, an inlet concentration increase and an interruption of the inlet air humidification for 48 h at an empty bed residence time (EBRT) of 240 s did not impact significantly on biodegradation performance, regardless of flow mode. Nevertheless, a reduction in the EBRT to 60 s resulted in a significant decrease in removal efficiency in all the biofilters. The CS₂ degradation profile showed that the reverse-flow mode strategy rendered a more homogenous distribution of biomass along the bed height. The benefits of the reverse-flow mode were demonstrated even when the unidirectional flow mode was re-established.

  11. THE USE OF BIOFILTERS FOR DEODORISATION OF THE NOXIOUS GASES

    Directory of Open Access Journals (Sweden)

    Monika Wierzbińska

    2015-01-01

    Full Text Available One of the methods of deodorization of noxious gases is biofiltration. This method consists of pollutants biodegradation by using micro-organisms, what leads to the formation of nontoxic and innoxious compounds. In comparison with conventional techniques, bio-filtration requires lower investments and exploitation costs, moreover it is nature friendly. This technique is still developing. Scientists have carried out research on the optimization of biofiltration process, biofilters and selecting parameters of purified gases or improving the method of efficiency. However, industrial application of biofilters is still difficult for many reasons. In this paper we present the mechanism of biofiltration process, the parameters and conditions which have to be fulfilled by purified gases, installation structure for gases biofiltration, application field of this method and specific example of exploited biofilters, including practical operational guidelines.

  12. Numerical simulation on the reduction of flow heterogeneity in the biofilter media

    Science.gov (United States)

    Yan, Weiwei; Liu, Xingli; Wu, Jie; Wei, Yikun; Xu, Peng

    2016-02-01

    The biofilters are the ideal solutions for the biological treatment of air pollutants. However, there exists strong flow heterogeneity in porous media that degrades the removal efficiency of biofilters. Thus, the effects of Darcy number, Reynolds number and porosity of porous media on the reduction of flow heterogeneity in three biofilter models were numerically studied by the lattice Boltzmann method. The simulation results lead to three conclusions: (1) The Darcy number has dominant influence on the flow heterogeneity in the biofilters. The reduction of flow heterogeneity can be realized by designing a comparatively low Darcy number. (2) The Reynolds number has obvious effect on the flow heterogeneity in the biofilters. However, the reduction of flow heterogeneity cannot be effectively established by regulating the Reynolds number. (3) The property of porous media greatly influences the flow heterogeneity in the biofilters. The present results are helpful for the optimized design of practical biofilter models.

  13. Validation of stormwater biofilters using in-situ columns.

    Science.gov (United States)

    Zhang, Kefeng; Valognes, Valentin; Page, Declan; Deletic, Ana; McCarthy, David

    2016-02-15

    Stormwater harvesting biofilters need to be validated if the treatment is to be relied upon. Currently, full-scale challenge tests (FCTs), performed in the field, are required for their validation. This is impractical for stormwater biofilters because of their size and flow capacity. Hence, for these natural treatment systems, new tools are required as alternatives to FCT. This study describes a novel in-situ method that consists of a thin stainless steel column which can be inserted into constructed biofilters in a non-destructive manner. The in-situ columns (ISCs) were tested using a controlled field-scale biofilter where FCT is possible. Fluorescein was initially used for testing through a series of continuous applications. The results from the ISC were compared to FCT conducted under similar operational conditions. Excellent agreement was obtained for the series of continuous fluorescein experiments, demonstrating that the ISC was able to reproduce FCT results even after extended drying periods (Nash-Sutcliffe coefficient between the two data sets was 0.83-0.88), with similar plateaus, flush peaks, slopes and treatment capacities. The ISCs were then tested for three herbicides: atrazine, simazine and prometryn. While the ISC herbicide data and the FCT data typically matched well, some differences observed were linked to the different climatic conditions during the ISC (winter) and FCT tests (summer). The work showed that ISC is a promising tool to study the field performance of biofilters and could be a potential alternative to full scale challenge tests for validation of stormwater biofilters when taking into account the same inherent boundary conditions.

  14. Biofilter Treating Ammonia Gas Using Agricultural Residues Media

    Directory of Open Access Journals (Sweden)

    Thaniya Kaosol

    2012-01-01

    Full Text Available Problem statement: Agricultural residues such as manure and sugarcane bagasse are wastes from agro-industry which has low value and requires some sustainable waste management method. In this research, a mixture of manure fertilizer and sugarcane bagasse is used as a biofilter media for an ammonia gas removal application. The aim of this research is to study the ammonia gas removal efficiency of such media. Approach: The experiments were conducted in laboratory-scale biofilters. Two inlet ammonia gas concentrations were used which are 500 and 1,000 ppm. Three ratios of manure fertilizer and sugarcane bagasse were studied including 1:3, 1:5 and 1:7 by volume. All experiments were conducted for a period of 40 days. Two Empty Bed Retention Time (EBRT of these experiments were used which is 39s and 78s. The moisture content of the biofilter media was maintained at 45-60% by adding water. Results: The maximum ammonia gas removal efficiency at 89.93% is observed from the following conditions: 500 ppm of the inlet ammonia gas concentration, the manure fertilizer and sugarcane bagasse mixture ratio of 1:5 and the EBRT of 78s. The important factors of the ammonia gas removal in biofiltration process are the inlet ammonia gas concentration and the EBRT. Conclusion: The experimental results showed that the mixture of manure fertilizer and sugarcane bagasse is an effective biofilter media for ammonia gas removal applications. However, the biofilter is more effective at low inlet ammonia gas concentration, while the ratio of manure fertilizer and sugarcane bagasse has no significant effect on the ammonia gas removal efficiency. Therefore, using both residues as biofilter media for ammonia gas removal application is an alternative sustainable way to such manage argo-industry waste.

  15. Biodegradation of mixture of VOC's in a biofilter

    Institute of Scientific and Technical Information of China (English)

    D. Arulneyam; T. Swaminathan

    2004-01-01

    Volatile organic compounds(VOC' s) in air have become major concem in recent years. Biodegradation of a mixture of ethanol and methanol vapor was evaluated in a laboratory biofilter with a bed of compost and polystyrene particles using an acclimated mixed culture. The continuous performance of the biofilter was studied with different proportion of ethanol and methanol at different initial concentration and flow rates. The result showed significant removal for both ethanol and methanol, which were composition dependent.The presence of either compound in the mixture inhibited the biodegradation of the other.

  16. Empirical tight-binding modeling of ordered and disordered semiconductor structures; Empirische Tight-Binding-Modellierung geordneter und ungeordneter Halbleiterstrukturen

    Energy Technology Data Exchange (ETDEWEB)

    Mourad, Daniel

    2010-11-30

    In this thesis, we investigate the electronic and optical properties of pure as well as of substitutionally alloyed II-VI and III-V bulk semiconductors and corresponding semiconductor quantum dots by means of an empirical tight-binding (TB) model. In the case of the alloyed systems of the type A{sub x}B{sub 1-x}, where A and B are the pure compound semiconductor materials, we study the influence of the disorder by means of several extensions of the TB model with different levels of sophistication. Our methods range from rather simple mean-field approaches (virtual crystal approximation, VCA) over a dynamical mean-field approach (coherent potential approximation, CPA) up to calculations where substitutional disorder is incorporated on a finite ensemble of microscopically distinct configurations. In the first part of this thesis, we cover the necessary fundamentals in order to properly introduce the TB model of our choice, the effective bond-orbital model (EBOM). In this model, one s- and three p-orbitals per spin direction are localized on the sites of the underlying Bravais lattice. The matrix elements between these orbitals are treated as free parameters in order to reproduce the properties of one conduction and three valence bands per spin direction and can then be used in supercell calculations in order to model mixed bulk materials or pure as well as mixed quantum dots. Part II of this thesis deals with unalloyed systems. Here, we use the EBOM in combination with configuration interaction calculations for the investigation of the electronic and optical properties of truncated pyramidal GaN quantum dots embedded in AlN with an underlying zincblende structure. Furthermore, we develop a parametrization of the EBOM for materials with a wurtzite structure, which allows for a fit of one conduction and three valence bands per spin direction throughout the whole Brillouin zone of the hexagonal system. In Part III, we focus on the influence of alloying on the electronic and optical properties. Therefore, we introduce the combination of the EBOM with the VCA, the CPA and the simulation of exact substitutional disorder on finite ensembles and systematically compare the results. We then use the TB model to calculate the nonlinear dependence of the band gap of bulk Cd{sub x}Zn{sub 1-x}Se on the concentration x and draw the comparison to experimental results. As an application to mixed quantum dots, we calculate the optical spectra of alloyed Cd{sub x}Zn{sub 1-x}Se nanocrystals and again compare our results to experimental data from the literature. Special attention is paid to the proper choice of material parameters and the elimination of spurious results. For the Cd{sub x}Zn{sub 1-x}Se bulk system, as well as for the nanocrystals of the same material, the combination of the EBOM with disorder on a finite ensemble yields results in very good agreement with the experiments. We close this work with results for the concentration-dependent band gap of cubic bulk Ga{sub x}Al{sub 1-x}N as an outlook to future applications. (orig.)

  17. Analysis and modelling of the energy requirements of batch processes; Analyse und Modellierung des Energiebedarfes in Batch-Prozessen

    Energy Technology Data Exchange (ETDEWEB)

    Bieler, P.S.

    2002-07-01

    This intermediate report for the Swiss Federal Office of Energy (SFOE) presents the results of a project aiming to model the energy consumption of multi-product, multi-purpose batch production plants. The utilities investigated were electricity, brine and steam. Both top-down and bottom-up approaches are described, whereby top-down was used for the buildings where the batch process apparatus was installed. Modelling showed that for batch-plants at the building level, the product mix can be too variable and the diversity of products and processes too great for simple modelling. Further results obtained by comparing six different production plants that could be modelled are discussed. The several models developed are described and their wider applicability is discussed. Also, the results of comparisons made between modelled and actual values are presented. Recommendations for further work are made.

  18. Characteristics and modeling of spruce wood under dynamic compression load; Charakteristik und Modellierung von Fichtenholz unter dynamischer Druckbelastung

    Energy Technology Data Exchange (ETDEWEB)

    Eisenacher, Germar

    2014-01-28

    Spruce wood is frequently used as an energy absorbing material in impact limiters of packages for the transportation of radioactive material. A 9m drop test onto an unyielding target is mandatory for the packages. The impact results in a dynamic compression load of the spruce wood inside the impact limiter. The lateral dilation of the wood is restrained thereby due to encasing steel sheets. This work's objective was to provide a material model for spruce wood based on experimental investigations to enable the calculation of such loading conditions. About 600 crush tests with cubical spruce wood specimens were performed to characterize the material. The compression was up to 70% and the material was assumed to be transversely isotropic. Particularly the lateral constraint showed to have an important effect: the material develops a high lateral dilation without lateral constraint. The force-displacement characteristics show a comparably low force level and no or only slight hardening. Distinctive softening occurs after the linear-elastic region when loaded parallel to the fiber. On the other hand, using a lateral constraint results in significantly higher general force levels, distinctive hardening and lateral forces. The softening effect when loaded parallel to the fiber is less distinctive. Strain rate and temperature raise or lower the strength level, which was quantified for the applicable ranges of impact limiters. The hypothesis of an uncoupled evolution of the yield surface was proposed based on the experimental findings. It postulates an independent strength evolution with deviatoric and volumetric deformation. The hypothesis could be established using the first modeling approach, the modified LS-DYNA material model MAT075. A transversely isotropic material model was developed based thereupon and implemented in LS-DYNA. The material characteristics of spruce wood were considered using a multi-surface yield criterion and a non-associated flow rule. The yield criterion uses linear interpolation of the strength of constrained and unconstrained spruce wood. Thus multiaxial stress states can be considered. The calculation of the crush tests showed the ability of the model to reproduce the basic strength characteristics of spruce wood. The effect of lateral constraint can be reproduced well due to the uncoupled evolution of the yield surface. On the contrary, the strength is overestimated for load under acute angles, which could be prevented using modified yield surfaces. The effects of strain rate and temperature are generally reproduced well but the scaling factors used should be improved. The calculation of a drop test with a test-package equipped with wood-filled impact limiters confi rmed the model's performance and produced feasible results. However, to create a verified impact limiter model further numerical and experimental investigations are necessary. This work makes an important contribution to the numerical stress analysis in the context of safety cases of transport packages.

  19. Structured modelling and nonlinear analysis of PEM fuel cells; Strukturierte Modellierung und nichtlineare Analyse von PEM-Brennstoffzellen

    Energy Technology Data Exchange (ETDEWEB)

    Hanke-Rauschenbach, R.

    2007-10-26

    In the first part of this work a model structuring concept for electrochemical systems is presented. The application of such a concept for the structuring of a process model allows it to combine different fuel cell models to form a whole model family, regardless of their level of detail. Beyond this the concept offers the opportunity to flexibly exchange model entities on different model levels. The second part of the work deals with the nonlinear behaviour of PEM fuel cells. With the help of a simple, spatially lumped and isothermal model, bistable current-voltage characteristics of PEM fuel cells operated with low humidified feed gases are predicted and discussed in detail. The cell is found to exhibit current-voltage curves with pronounced local extrema in a parameter range that is of practical interest when operated at constant feed gas flow rates. (orig.)

  20. Modeling and simulation of high-temperature polymer electrolyte fuel cells; Modellierung und Simulation von Hochtemperatur-Polymerelektrolyt-Brennstoffzellen

    Energy Technology Data Exchange (ETDEWEB)

    Kvesic, Mirko

    2012-07-01

    Fuel cells are electrochemical energy converters that convert chemical energy of constantly fed reactants directly into electricity. The most commonly used fuel gas in this respect is hydrogen, which is either produced in pure form by electrolysis, for example, or as a hydrogen-rich gas mixture (reformate gas), produced by reforming diesel or kerosene e.g. However, a disadvantage of reformate gas is that it contains additional carbon monoxide (CO), which leads to catalyst poisoning in the fuel cell. Since higher operating temperatures also lead to a higher CO tolerance, the use of high-temperature Polymer-Electrolyte-Fuel-Cells (HT-PEFCs) is particularly suitable for reformate operation. The aim of the presented work is the modeling and CFD-simulation of HT-PEFC stacks with the intention of gaining a better understanding of multi-physical processes in the stack operation as well as the optimization and analysis of existing stack designs. The geometric modeling used is based on the Porous Volume Model, which significantly reduces the required number of computing elements. Furthermore, the electrochemical models for hydrogen / air and reformate / air operation, which were taking the CO poisoning effects into account, are developed in this work and implemented in the software ANSYS / Fluent. The resulting simulations indicated the optimal flow configuration for the stack operation in terms of the homogeneous current density distribution, which has a positive effect on the stack aging. Thus, the current densities showed a strong homogeneity regarding the stack configuration anode / cathode in counter-flow and anode / cooling in co-flow. The influence of cooling strategies was examined for the stack performance in a similar way. In the following, the local temperature distribution as well as temperature peaks within the stack could be predicted and validated with experimental measurements. Further on, the model scalability and thus the general validity of the developed modeling approach have been demonstrated. Consequently, the applied modeling approach as well as the obtained conclusions can be used as high-quality support in the development of HT-PEFC-stacks, which are particularly intended for the power supply for auxiliary power units (APUs) in lorries, ships and aircrafts.

  1. Modelling and optimization of car-to-car compatibility - Modellierung und optimierung von pkw-pkw-kompatibilität

    NARCIS (Netherlands)

    Mooi, H.G.; Nastic, T.; Huibers, J.H.A.M.

    1999-01-01

    In this paper simple and more detailed MADYMO multibody models were used to simulate the car structure for improving the car-to-car compatibility of the whole car fleet. As a first step, survey studies were performed to develop a method for the optimization of car design with respect to frontal and

  2. Operational simulation, design and management of decentralized energy systems; Betriebliche Modellierung, Auslegung und Management von dezentralen Energiesystemen

    Energy Technology Data Exchange (ETDEWEB)

    Matics, J.

    2007-06-28

    Chapter 2 describes the worldwide increase of primary energy consumption, which is expected in coming decades and results in possible solutions of a decentralised energy supply that is mainly based upon renewable energy carriers and the use of cogeneration systems. Chapter 3 shows the characteristics of decentralised system components that have been investigated in the frame of this research work as well as the resulting model library to depict the operational performance of the individual components and their mutual influence. A detailed dynamic simulation of a complete fuel cell system based on a steam reformer including the concept of local and superordinate control circuits is presented in chapter 4. Chapter 5 includes the integrated concepts for the intelligent and adaptable management of complex decentralised energy systems as well as a description of their implementation. Apart from the applied metaheuristic optimization methods the adaptable fuzzy-system, used in this case, is presented. The components of the model library of decentralised system components (chapter 3), the dynamic simulation of a complete fuel cell system based on a reformer (chapter 4), as well as the intelligent and adaptable plant management (chapter 5) are used in chapter 6 to investigate the various decentralised energy systems. The investigation focuses in particular on a) the electricity supply of a one-family home based on photovoltaics including different storage technologies and an increasing degree of energetic independence; b) the operational performance of a wind park with 72 individual plants as well as the combination of flywheel mass storage and wind energy plant; c) the control concepts, which have been developed for a fuel cell test stand based on a steam reformer, and their effects on the operation of the individual components as well as their interaction; d) the use of the developed management modules for the flexible and adaptable operation of a cogeneration system for house energy supply. In chapter 7 the contributions in the frame of this research work for the operational simulation, design and management of decentralized energy systems are summarized. (orig.)

  3. Thermal modelling of borehole heat exchangers and borehole thermal energy stores; Zur thermischen Modellierung von Erdwaermesonden und Erdsonden-Waermespeichern

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Dan

    2011-07-15

    The thermal use of the underground for heating and cooling applications can be done with borehole heat exchangers. This work deals with the further development of the modelling of thermal transport processes inside and outside the borehole as well as with the application of the further developed models. The combination of high accuracy and short computation time is achieved by the development of three-dimensional thermal resistance and capacity models for borehole heat exchangers. Short transient transport processes can be calculated by the developed model with a considerable higher dynamic and accuracy than with known models from literature. The model is used to evaluate measurement data of a thermal response test by parameter estimation technique with a transient three-dimensional model for the first time. Clear advantages like shortening of the test duration are shown. The developed borehole heat exchanger model is combined with a three-dimensional description of the underground in the Finite-Element-Program FEFLOW. The influence of moving groundwater on borehole heat exchangers and borehole thermal energy stores is then quantified.

  4. Modeling of transports of water and matter in landscape. Proceedings; Modellierung des Wasser- und Stofftransportes in grossen Einzugsgebieten. Beitraege

    Energy Technology Data Exchange (ETDEWEB)

    Bronstert, A.; Krysanova, V.; Schroeder, A.; Becker, A.; Bork, H.R. [eds.

    1998-04-01

    During recent years, the quantitative description of the water fluxes and the coupled transport of physical and chemical matter in the landscape has become steadily more and more important. The reasons for this are an increasing public awareness about the possible impacts of changes of land use, land cover, and of changes in regional and global climatic conditions together with a need for sound, multi-objective management of large river basins. The investigation areas of concern a usually much larger in extent than a typically sized hydrological investigation catchment. The tools primarily used in the quantification of the hydrological fluxes at the large scale are the so-called large-scale hydrological models. These models are comparatively new and still at the stage of development and improvement. The mentioned need for advanced large-scale hydrological models provided the reason for inviting scientists from German-speaking countries with experience in large-scale hydrological and hydro-meteorological models to exchange and discuss their modelling concepts and to identify research needs. The workshop was held at the Potsdam Institute for Climate Impact Research (PIK) on 15 and 16 December 1997, and was jointly organised by PIK, the University of Potsdam and the Centre for Agriculture and Land Use Research (ZALF). The workshop was attended by over 40 scientists, of whom 19 gave a presentation. (orig.)

  5. Modeling and simulation of communication networks for smart grid applications; Modellierung und Simulation von Kommunikationsnetzen fuer Smart Grid Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Benoit, Pascal; Rohbogner, Gregor; Fey, Simon; Kohrs, Robert; Wittwer, Christof [Fraunhofer-Institut fuer Solare Energiesysteme (ISE), Freiburg im Breisgau (Germany)

    2012-07-01

    Communication systems will facilitate different new applications in the future Smart Grid. Hence, the design of these systems is of particular importance regarding security, flexibility, usability, robustness and functionality concerns. This article works out the questions for which modeling and simulation of communication networks can be used in finding an engineering solution. Furthermore, it gives a brief overview of the available simulation tools today. Multiagent systems and large-scale photovoltaic plants with tracking systems are two communication intensive applications which are considered as showcases. A model of such a plant will be presented as well as the result of a validation experiment. (orig.)

  6. Final presentation of the joint project: Laser-diagnostic and plasma-technological fundamentals of emission reduction and fuel consumption reduction in DI internal combustion engines. Results of subprojects; Abschlusspraesentation zum Verbundprojekt: Laserdiagnostische und plasmatechnologische Grundlagen zur Verminderung von Emissionen und Kraftstoffverbrauch von DI-Verbrennungsmotoren. Ergebnisse der Teilvorhaben

    Energy Technology Data Exchange (ETDEWEB)

    Reichel, K.; Sellhorst, M. (eds.)

    2000-07-01

    New combustion processes, especially DI combustion processes, can be developed quickly and efficiently only if efficient and industrially applicable processes are available for investigating the processes of combustion in engines, for ignition of locally varying fuel/air mixtures, and for treatment of exhaust of nonstoichiometric combustion processes. The project aimed at the development and testing of laser diagnostic methods, numerical models and plasma processes. The conference comprised the sections: Processes inside the engine; processes behind the engine; system aspects. [German] Zielstellung des Verbundprojektes ist die Verminderung von Emissionen und Kraftstoffverbrauch von neuartigen motorischen Brennverfahren, von denen der direkteinspritzende (DI) Verbrennungsmotor die guenstigsten Voraussetzungen liefert und damit ein Potential bereitstellt, die zukuenftig geforderten Emissions-Grenzwerte entsprechend der gesetzlich vorgegebenen Euro-Normen zu erreichen. Neuartige, insbesondere direkteinspritzende Brennverfahren koennen von der Automobilindustrie jedoch nur dann schnell und effizient erarbeitet werden, wenn geeignete, von der Industrie einsetzbare Verfahren - zur Untersuchung von Wirkketten der motorischen Verbrennung, - zur Zuendung oertlich schwankender Kraftstoff-Luft-Gemische, - zur Abgasnachbehandlung von Abgasen aus nichtstoechiometrischer Verbrennung zur Verfuegung stehen. Ziel des geplanten Verbundprojektes war es also, laserdiagnostische Analyseverfahren, Verfahren der numerischen Modellierung und grundlegende plasmatechnologische Verfahren zu untersuchen und weitestgehend zu erproben, damit die Verfahren oder die mit ihnen gewonnenen Erkenntnisse von der Industrie als Werkzeug eingesetzt werden koennen. Aus Sicht des Anwenders ergab sich dabei eine inhaltliche Einteilung in die Themenfelder: - Innermotorische Prozesse, - Nachmotorische Prozesse und - Systemaspekte. (orig.)

  7. Removal of pharmaceuticals in aerated biofilters with manganese feeding.

    Science.gov (United States)

    Zhang, Yongjun; Zhu, Hong; Szewzyk, Ulrich; Geissen, Sven Uwe

    2015-04-01

    A tertiary treatment step is required in current wastewater treatment plants to remove trace pollutants and thus to prevent their extensive occurrence in the aquatic environment. In this study, natural MnOx ore and natural zeolite were separately used to pack two lab-scale aerated biofilters, which were operated in approximately 1.5 years for the removal of frequently occurring pharmaceuticals, including carbamazepine (CBZ), diclofenac (DFC), and sulfamethoxazole (SMX), out of synthetic and real secondary effluents. Mn(2+) was added in the feeds to promote the growth of iron/manganese oxidizing bacteria which were recently found to be capable of degrading recalcitrant pollutants. An effective removal (80-90%) of DFC and SMX was observed in both biofilters after adaptation while a significant removal of CBZ was not found. Both biofilters also achieved an effective removal of spiked Mn(2+), but a limited removal of carbon and nitrogen contents. Additionally, MnOx biofilter removed 50% of UV254 from real secondary effluent, indicating a high potential on the removal of aromatic compounds.

  8. Elimination of butanal from odorous air by a labscale biofilter

    NARCIS (Netherlands)

    Weckhuysen, B.M.; Vriens, L.; Verachtert, H.

    1991-01-01

    Butanal was chosen as a model compound for testing the performance of biofilters. It's a member of an important class of odour compounds released by waste water treatment plants of animal rendering and food processing industry. The influence of nutrient supplementation has been investigated using tw

  9. Liquid Film Diffusion on Reaction Rate in Submerged Biofilters

    DEFF Research Database (Denmark)

    Christiansen, Pia; Hollesen, Line; Harremoës, Poul

    1995-01-01

    Experiments were carried out in order to investigate the influence of liquid film diffusion on reaction rate in a submerged biofilter with denitrification and in order to compare with a theoretical study of the mass transfer coefficient. The experiments were carried out with varied flow, identified...

  10. Assessment of Biofilter Media Particle Sizes for Removing Ammonia

    Science.gov (United States)

    With increased concerns over odor and gas emissions from livestock production facilities more efficient technologies of air pollution control are needed to mitigate the deleterious effects of air contaminants. Gas-phase biofilters for treating contaminant gases from poultry and livestock operations ...

  11. Biofilter voorkomt emissie wasplaats : Interview met Rik de Werd

    NARCIS (Netherlands)

    Lee, H.; Werd, de H.A.E.

    2011-01-01

    Hoewel de exacte regels rond de afvoer van water van de wasplaats voor trekkers en spuiten nog op zich laten wachten, wordt door de praktijk en onderzoekers al volop gewerkt aan oplossingen. Loonbedrijven en akkerbouwers richten onder meer biofilters in om het water te reinigen. Lozen van het gezuiv

  12. DEVELOPMENT OF AEROBIC BIOFILTER DESIGN CRITERIA FOR TREATING VOCS

    Science.gov (United States)

    This paper reports preliminary results on the use of trickle bed biofilters with monolithic ceramic channelized microbial support structures for the treatment of VOCs typical of landfill leachate stripping. Toluene was used for the purpose of characterizing the trickle bed biofi...

  13. Combined denitrification and phosphorus removal in a biofilter

    DEFF Research Database (Denmark)

    Falkentoft, Christina Maria; Harremoes, Poul; Mosbæk, Hans;

    2000-01-01

    A lab-scale biofilter was run continuously for 11/2 years for combined denitrification and phosphorus removal. Alternation between anaerobic and anoxic (nitrate) conditions was used to obtain an enriched culture of denitrifying, phosphate accumulating organisms. Batch experiments were performed...

  14. Diskurs und Praxis: Geschlecht und Gewalt

    Directory of Open Access Journals (Sweden)

    Angela Koch

    2003-11-01

    Full Text Available Der Sammelband befasst sich kulturwissenschaftlich mit den Verschränkungen der diskursiven Repräsentationen von Geschlecht und Gewalt, mit deren alltäglichen Erscheinungsformen und juristischen Auslegungen. Im Vordergrund steht die personale Gewalttätigkeit als physisches Mittel des Zwangs, der Dominanz und der Macht. Der Band geht auf die Tagung „Frauen und Gewalt“ zurück, die im Oktober 2001 in Greifswald stattgefunden hat, und versammelt 18 Beiträge, die unterschiedliche Facetten des Themenkomplexes behandeln: Gewalt gegen Frauen wie Inzest, Vergewaltigung, Folter, Anprangerung im Internet, und weibliche Gewalttätigkeit wie Verbrechen, Mord, Kindsmord, physische Gewalt.

  15. Interaction of gaseous aromatic and aliphatic compounds in thermophilic biofilters.

    Science.gov (United States)

    Hu, Qing-yuan; Wang, Can

    2015-12-30

    Two thermophilic biofilters were applied in treating a mixture of gaseous aromatic (benzene) and aliphatic compounds (hexane) to evaluate the interaction of the compounds. The performance of the biofilters was investigated in terms of removal efficiencies, elimination capacity, kinetic analysis, interaction indices, and microbial metabolic characteristics. Results showed that the removal performance of benzene was unaffected by the addition of hexane. The removal efficiencies of benzene were maintained at approximately 80% and the biodegradation rate constant was maintained at 120 h(-1). However, the removal efficiencies of hexane decreased significantly from 60% to 20% and the biodegradation rate constant exhibited a distinct decrease from 93.59 h(-1) to 56.32 h(-1). The interaction index of benzene with the addition of hexane was -0.029, which indicated that hexane had little effect on the degradation of benzene. By contrast, the interaction index of hexane by benzene was -0.557, which showed that benzene inhibited the degradation of hexane significantly. Similar conclusions were obtained about the substrate utilization. Moreover, the utilization degree of carbon sources and the microbial metabolic activities in the biofilter treating hexane were significantly improved with the addition of benzene, whereas the addition of hexane had a slight effect on the microbial communities in the biofilter treating benzene. Conclusions could be obtained that when mixtures of benzene and hexane were treated using biofilters, the degradation of benzene, which was more easily degradable, was dominant and unaffected; whereas the degradation of hexane, which was less easily degradable, was inhibited because of the changing of microbes.

  16. Pluralistic heat supply concept. Strategies and technologies for decentralised district heating in a liberalized energy market with an emphasis on CHP technology and renewable energies. AGFW principal study, first part of work. Vol. 2. Part 1: District heating systems, existing stock of buildings. Part 2: Technology development and assessment; Pluralistische Waermeversorgung. Strategien und Technologien einer pluralistischen Fern- und Nahwaermeversorgung in einem liberalisierten Energiemarkt unter besonder Beruecksichtigung der Kraft-Waerme-Kopplung und regenerativer Energien. AGFW-Hauptstudie. 1. Bearbeitungsabschnitt. Bd. 2. T. 1: Waermeversorgung des Gebaeudebestandes. T. 2: Technologieentwicklung und -bewertung

    Energy Technology Data Exchange (ETDEWEB)

    Neuffer, H.; Witterhold, F.G. [Arbeitsgemeinschaft Fernwaerme e.V., Frankfurt am Main (Germany); Pfaffenberger, W. [Bremer Energie Institut, Bremen (DE)] [and others

    2001-08-01

    In order to prepare the basis for the comparative analysis of various carbon dioxide mitigation policies in terms of energy performance of buildings, economic efficiency and ecologic benefits, the wide variety of community district heating services is defined in part A, based on a very differential and extensive characterisation of selected dwellings and the building types. The last chapter of part A discusses the impacts of an enhanced CHP electricity production on the energy system of the Federal Republic of Germany. Part B explains the basic aspects and the approaches used for a building-specific modelling of the various structures of dwellings and the further development of methods applied for energy analysis and energy system modelling at the national level. (orig./CB) [German] Zur Vorbereitung des energetischen, oekonomischen und oekologischen Vergleichs verschiedener CO{sub 2}-Minderungsmassnahmen werden zunaechst in Teil A die unterschiedlichen Versorgungsaufgaben kommunaler Fernwaermeversorgungssysteme anhand einer sehr differenzierten und umfangreichen Charakterisierung der ausgewaehlten Siedlungs- und Gebaeudestrukturen definiert. Im letzten Kapitel von Teil A werden ausserdem die Rueckwirkungen einer verstaerkten KWK-Stromerzeugung auf das Energiesystem der Bundesrepublik Deutschland diskutiert. Teil B erlaeutert die Grundlagen und die Entwicklung der gebaeudescharfen Modellierung von Siedlungsstrukturen und eine Weiterentwicklung von Energiesystemmodellen. (orig./CB)

  17. Strömungs- und Tracer-Transportmodellierung am Natural Attenuation-Standort Zeitz

    Science.gov (United States)

    Gödeke, Stefan; Weiß, Holger; Geistlinger, Helmut; Fischer, Anko; Richnow, Hans Herrmann; Schirmer, Mario

    Kurzfassung Numerische Modelle spielen bei der Bewertung von Natural-Attenuation-Prozessen an Feldstandorten eine bedeutende Rolle. Daher ist es wichtig diese mit Felddaten zu überprüfen und gegebenenfalls erneut zu kalibrieren. Die Modellierung des Transports eines konservativen Tracers auf der Grundlage von Felddaten ergab eine zuverlässigere Abschätzung der Kf-Werte des numerischen Strömungsmodells für den Standort, als es mit anderen Methoden (z. B. Analyse der Siebwerte) möglich war. Die Kf-Werte berechnet aus Siebanalysen führten zu einer deutlichen Unterschätzung der Tracerausbreitungsgeschwindigkeit. Zwischen beobachteten und berechneten Durchbruchskurven wurde eine gute Übereinstimmung erzielt, sodass das Modell für die Planung weiterer Feldexperimente und als Grundlage für eine reaktive Transportmodellierung genutzt werden kann. Die hydraulischen Leitfähigkeiten im Untersuchungsgebiet ändern sich in vertikaler und horizontaler Richtung im Bereich weniger Dezimeter z. T. stark, was von dem numerischen Modell nur begrenzt wiedergegeben werden kann. Für die Modellierung der Tracerausbreitung ist die Kenntnis der Kf-Wert-Verteilung im Bereich des Infiltrationsbrunnens besonders wichtig, weil sie die Struktur der Tracerfahne im Abstrom wesentlich beeinflusst. Die Wahl des numerischen Verfahrens für die Lösung der Transportgleichung hatte bei der Kalibrierung des Strömungsmodells einen großen Einfluss. Während mit dem in MT3DMS vorhandenen TVD (〝Total Variation Diminishing``)-Algorithmus eine akzeptable Lösung gefunden wurde, zeigten sich bei der Verwendung des MOC (〝Method of Characteristics``)-Verfahrens signifikante Fehler in der Massenbilanz. Reliable numerical models are of primary importance for the evaluation of Natural-Attenuation processes at field sites. Modelling the flow and transport of a conservative tracer, a more realistic distribution of the hydraulic conductivity values for the numerical model was achieved and a good

  18. Microbial Community in a Biofilter for Removal of Low Load Nitrobenzene Waste Gas

    Science.gov (United States)

    Zhai, Jian; Wang, Zhu; Shi, Peng; Long, Chao

    2017-01-01

    To improve biofilter performance, the microbial community of a biofilter must be clearly defined. In this study, the performance of a lab-scale polyurethane biofilter for treating waste gas with low loads of nitrobenzene (NB) (microbial community were attributed to the different intermediate degradation products of NB in each layer. The strains identified in this study were potential candidates for purifying waste gas effluents containing NB. PMID:28114416

  19. Modelling and experimental investigation on the application of water super adsorbents in waste air biofilters.

    Science.gov (United States)

    Danaee, Soroosh; Fazaelipoor, Mohammad Hassan; Gholami, Abdollah; Ataei, Seyed Ahmad; Afzali, Daryoush

    2015-01-01

    In this research work, a synthetic water super absorbent polymer was included in the bed of a perlite-based biofilter for the removal of ethanol from air. The performance of this biofilter was compared with the performance of a control perlite-based biofilter lacking the water super absorbent. With the empty bed residence time of 2 min, both biofilters were able to remove more than 90% of the entering pollutant with the concentration of 1 g /m3, when regular moistening was applied. After last irrigation on day 23, the performance of the control biofilter was unchanged until day 35. From day 36 onwards, the control biofilter lost its activity gradually and became totally inactive on day 45. The performance of the super absorbent containing biofilter, however, was unchanged until day 58 before starting to lose its activity. A mechanistic model was developed to describe the performance of a biofilter under drying effects. The model could predict the trends of experimental results reasonably well. The model was also applied to predict the trends of experimental data from a published paper on the removal of hexane in a perlite/super absorbent containing biofilter.

  20. Assessment of microbial populations in methyl ethyl ketone degrading biofilters by denaturing gradient gel electrophoresis.

    Science.gov (United States)

    Li, C; Moe, W M

    2004-05-01

    Denaturing gradient gel electrophoresis (DGGE) analysis of polymerase chain reaction-amplified genes coding for 16S rRNA was used to assess differences in bacterial community structure as a function of spatial location along the height of two biofilters used to treat a model waste gas stream containing methyl ethyl ketone (MEK). One of the laboratory-scale biofilters was operated as a conventional continuous-flow biofilter (CFB) and the other was operated as a sequencing batch biofilter (SBB). Both biofilters, inoculated with an identical starting culture and operated over a period lasting more than 300 days, received the same influent MEK concentration and same mass of MEK on a daily basis. The systems differed, however, in terms of the fraction of time during which contaminated air was supplied and the overall operating strategy employed. DGGE analysis indicated that microbial community structures differed as a function of height in each of the biofilters. The DGGE banding patterns also differed between the two biofilters, suggesting that operating strategies imposed on the biofilters imparted a sufficiently large selective pressure to influence microbial community structures. This may explain, in part, the superior performance of the SBB over the CFB during model transient loading conditions, and it may open new possibilities for purposely manipulating the microbial populations in biofilters treating gas-phase contaminants in a manner that leads to more favorable treatment performance.

  1. Variations in dissolved organic nitrogen concentration in biofilters with different media during drinking water treatment.

    Science.gov (United States)

    Zhang, Huining; Zhang, Kefeng; Jin, Huixia; Gu, Li; Yu, Xin

    2015-11-01

    Dissolved organic nitrogen (DON) is potential precursor of disinfection byproducts (DBPs), especially nitrogenous DBPs. In this study, we investigated the impact of biofilters on DON concentration changes in a drinking water plant. A small pilot plant was constructed next to a sedimentation tank in a drinking water plant and included activated carbon, quartz sand, anthracite, and ceramsite biofilters. As the biofilter layer depth increased, the DON concentration first decreased and then increased, and the variation in DON concentration differed among the biofilters. In the activated carbon biofilter, the DON concentration was reduced by the largest amount in the first part of the column and increased by the largest amount in the second part of the column. The biomass in the activated carbon filter was less than that in the quartz sand filter in the upper column. The heterotrophic bacterial proportion among bacterial flora in the activated carbon biofilter was the largest, which might be due to the significant reduction in DON in the first part of the column. Overall, the results indicate that the DON concentration in biofiltered water can be controlled via the selection of appropriate biofilter media. We propose that a two-layer biofilter with activated carbon in the upper layer and another media type in the lower layer could best reduce the DON concentration.

  2. Performance of low pH biofilters treating a paint solvent mixture: continuous and intermittent loading.

    Science.gov (United States)

    Qi, Bing; Moe, William M

    2006-07-31

    Two biofilters packed with a reticulated polyurethane foam medium were inoculated with a compost-derived enrichment culture grown under acidic conditions (pH 3.0) and then operated over a period lasting 63 days. Both biofilters were supplied with a humidified gas stream containing a five-component mixture of acetone, methyl ethyl ketone, toluene, ethylbenzene, and p-xylene at a total VOC loading rate 80.3 gm(-3)h(-1) to simulate treatment of air emissions resulting from manufacture of reformulated paint. One biofilter was operated under continuous loading conditions and the other received intermittent loading with contaminants supplied only 8 h/day. Nutrient solution with pH 3.0 was supplied approximately once per week to provide nitrogen and other nutrients. Data are presented which demonstrate that undefined mixed cultures acclimated at low pH can successfully treat paint solvent mixtures in biofilters. The biofilter receiving continuous loading reached high overall removal efficiency (greater than 90% overall removal) 3 weeks after startup, and performance increased over time reaching overall removal in the range of 97-99% after 50 days. Performance of the intermittently loaded biofilter developed more slowly, requiring 6 weeks to stabilize at an overall removal efficiency in excess of 90%. In both biofilters, ketone components were more rapidly degraded than aromatic components, and removal of aromatic compounds was somewhat unstable even after 2 months of biofilter operation. Scanning electron microscopy (SEM) revealed that fungi dominated the microbial populations in both biofilters.

  3. Determination of the deposition of polycyclic aromatic hydrocarbons (PAHs) to soil at Scheyern and Kirchheim near Munich; Bestimmung der Eintraege von polyzyklischen aromatischen Kohlenwasserstoffen (PAHs) an den Standorten Scheyern und Kirchheim bei Muenchen

    Energy Technology Data Exchange (ETDEWEB)

    Krainz, A.; Wiedenmann, M.; Maguhn, J. [GSF-Forschungszentrum fuer Umwelt und Gesundheit Neuherberg (Germany). Inst. fuer Oekologische Chemie

    1997-12-31

    Task force 1, ``Analysis of the exposure of soils``, carried out comprehensive and site-specific measurements of the transfer of environmental chemicals into soil by means of the example of s-triazines and polycyclic aromatic hydrocarbons (PAHs). This work was in four parts: a: Determination of PAH nuisance concentrations in selected sites (Juelich, Scheyern, Bad Lauchstaedt); b: Measurement of wet deposition, development and use of methods for the determination of dry deposition; c: Statements regarding large-area PAH transfer into soil in Germany; d: Modelling of the rates of dry deposition. (orig.) [Deutsch] Aufgabe der Arbeitsgruppe 1 `Belastungsanalyse von Boeden`: Flaechendeckende sowie standortbezogene Erfassung der Eintraege von Umweltchemikalien am Beispiel der s-Triazine und PAHs. a: Bestimmung der Immissionskonzentrationen von PAHs an den Schwerpunktstandorten (Juelich, Scheyern, Bad Lauchstaedt) b: Messung der Nassen Deposition, Entwicklung und Anwendung von Methoden zur Bestimmung der Trockenen Deposition c: Aussagen ueber flaechendeckende Eintraege von PAHs in der Bundesrepublik d: Modellierung der Trockendepositionsraten. (orig.)

  4. Physikdidaktik Theorie und Praxis

    CERN Document Server

    Girwidz, Raimund; Häußler, Peter

    2015-01-01

    „Physikdidaktik – Theorie und Praxis“ ist ein Sammelband, der dynamisch gewachsen ist. Der Teil I wurde im Jahre 2000 in erster Linie für Studierende des Lehramts Physik konzipiert. Der Teil II zeigt Konkretisierungen und im Unterricht erprobte Beispiele zu neueren didaktischen und methodischen Ansätzen, die aus der Pädagogik und der allgemeinen Didaktik für die Physikdidaktik aufbereitet wurden. Die Physikdidaktik befasst sich natürlich auch mit der Frage, welche Elemente aus der modernen Physik in den Unterricht eingehen können und sollen. Vor der Aufbereitung der Inhalte für den Unterricht, mit Vereinfachungen und angemessenen didaktischen Reduktionen, steht die Sachanalyse und die Zusammenfassung von interessanten Themen aus aktuellen experimentellen und theoretischen Arbeitsgebieten der Physik (Teil III). In der vorliegenden 3. Ausgabe eines Gesamtbandes „Physikdidaktik – Theorie und Praxis“ wurden Astrophysik, Elementar­teilchenphysik und Biophysik als interessante Beispiele aus ...

  5. Frauen und Sucht : Literaturkompendium

    OpenAIRE

    Franke, Alexa; Mohn, Karin; Welbrink, Andrea; Witte, Maibritt; Teuber, Jutta

    2000-01-01

    Das vorliegende Literaturkompendium stellt die aktuelle wissenschaftliche Literatur zu dem Thema "Frauen und Sucht" systematisch und möglichst umfassend dar. Es beinhaltet Literaturhinweise zu frauenspezifischen Ursachen, Bedingungen, Verläufen und Folgen des Substanzmißbrauchs. Zur besseren Überschaubarkeit und um den Umfang der Recherche einzugrenzen, bezieht sich das Kompendium ausschließlich auf folgende Substanzen: Alkohol, Medikamente und illegale Drogen. Grundlage des Kompendiums ...

  6. Form und Leben zwischen Positivismus und Idealismus

    Directory of Open Access Journals (Sweden)

    Kai Nonnenmacher

    2015-02-01

    Full Text Available Der Artikel skizziert bei u.a. Dilthey, Hofmannsthal, Rilke, Bergson, Vossler und Croce in vier Schritten den Zusammenhang zwischen der Lebensphilosophie und der idealistischen Neuphilologie, die Frage poetischer Autonomie mit diesem spezifischen Wissensbegriff um 1900 verknüpfend:1. Antipositivismus als Folie eines neuen Wissensbegriffs um 1900;2. Wissensschau einer lebensphilosophischen Poetik;3. Autonomie und Leben;4. Diskursgeschichte literarischer Autonomie.Der Artikel geht zurück auf einen Vortrag bei der von der Thyssen-Stiftung geförderten Tagung „Kunst, Erkenntnis, Wissenschaft (techne und episteme, ars und scientia“ von Marion Hiller, Hochschule Vechta, 2011. 

  7. Effects of addition of straw, chitin and manure to new or recycled biofilters on their pesticides retention and degradation properties.

    Science.gov (United States)

    Genot, P; Van Huynh, N; Debongnie, Ph; Pussemier, L

    2002-01-01

    Pollution of surface and groundwater by pesticides is an increasing problem that needs to be addressed by the authorities as well as by the farmers themselves. Nowadays, some researchers are considering the numerous small spillages at the farm sites as a relevant entry route to be taken into account for predicting surface and groundwater pollution. In order to tackle this problem, several solutions exist for limiting the disposal of pesticide wastes into the environment. One such system is biopurification of farm wastes by biobed, biofilter or phytobac. In this study, the results of pesticides retention by biofilters under outdoor conditions are presented. The biofilters were filled with a mixture of a soil + peat constituent (25% by volume for each of them) and the rest (50%) with straw or with composted manure ot with chitin (in this later case at the rate of 5 g chitin per liter of substrate). The soil + peat constituent was made either of a material already challenged by pesticides (= recycled biofilters) or of untreated material (new biofilters). Selected pesticides (atrazine, carbofuran, chloridazon, chlortoluron, cyanazine, isoproturon and lenacil) were applied onto biofilters and the eluates were collected and analyzed. Two successive injections of pesticides into the biofilters were conducted. After the first pesticides application, the recycled biofilters made of soil + peat previously treated with pesticides had better retention and degradation rates than the new biofilters. Adding manure also improved these properties of biofilters. Columns made of unchallenged soil + peat and straw (new biofilters) were the least satisfactory: up to 25% of carbofuran were lost. Biofilters made of unchallenged soil + peat and chitin retained the least lenacil. Atrazine was the most retained by biofilters (either new or recycled) with added chitin. Cyanazine was almost absent in the percolates of all biofilters. After the second application of carbofuran and isoproturon

  8. Optical and energetic characterisation of window/blind-systems; Optische und energetische Charakterisierung von Fenster/Jalousie-Systemen

    Energy Technology Data Exchange (ETDEWEB)

    Haug, I.; Beck, A.; Fricke, J. [Bayerisches Zentrum fuer Angewandte Energieforschung e.V., Wuerzburg (Germany)

    2000-02-01

    The energetic behavior of venetian blinds is a central point of international research in building physics. The aim is to quantify the energy transport mechanisms and to improve standardization. A model to determine the total solar energy transmittance (g-value) of a system consisting of inside blinds and an insulating glass unit is presented on the basis of ray-tracing and Monte-Carlo algorithms. The components are optically characterized and a parameter study for white, specular reflecting and black blinds is performed. It is shown that the g-value can be determined without a detailled thermal model. Also the description of the lind surface via angular dependent reflectance is new. The fact is quantified that inside venetian blinds are effective shading devices and outside blinds additionally are heat protection devices. (orig.) [German] Die Untersuchung des energetischen Verhaltens von Jalousien steht derzeit im Mittelpunkt internationaler Forschungsaktivitaeten im Bereich Fenstersysteme. Ziel ist es, den Energietransport zu beschreiben, und die Ergebnisse in die Normgebung mit einzubeziehen. Auf der Basis von Strahlverfolgungs- und Monte-Carlo-Algorithmen sowie Extremalbetrachtungen wird ein Berechnungsmodell des Gesamtenergiedurchlassgrades (g-Wert) von innen- und aussenliegenden Jalousien in Kombination mit einer Waermeschutzverglasung vorgestellt. Die einzelnen Systemkomponenten werden detailliert optisch charakterisiert. Abschliessend folgt eine Parameterstudiede fuer weisse, spiegelnde und schwarze Jalousien an unterschiedlichen Positionen und fuer verschiedene Lamellenstellungen. Hierdurch wird gezeigt, dass ohne eine ausfuehrliche thermische Modellierung des Fenster/Jalousie-Systems quantitativ der g-Wert bestimmt werden kann. Neu ist auch die Oberflaechencharakterisierung der Jalousie durch Verwendung von winkelabhaengigen Reflexionsgraden. Die Tatsache, dass innenliegende Jalousien einen effizienten Blendschutz und aussenliegende Jalousien einen

  9. Restaurant emissions removal by a biofilter with immobilized bacteria

    Institute of Scientific and Technical Information of China (English)

    MIAO Jian-yu; ZHENG Lian-ying; GUO Xiao-fen

    2005-01-01

    Pseudomonas sp. ZD8 isolated from contaminated soil was immobilized with platane wood chips to produce packing materials for a novel biofilter system utilized to control restaurant emissions. The effects of operational parameters including retention time, temperature, and inlet gas concentration on the removal efficiency and elimination capacity were evaluated. Criteria necessary for a scale-up design of the biofilter was established. High and satisfactory level of rapeseed oil smoke removal efficiency was maintained during operation and the optimal retention time was found to be 18 s corresponding to smoke removal efficiency greater than 97%. The optimal inlet rapeseed oil smoke loading was 120 mg/(m3.h) at the upper end of the linear correlation between inlet loading and elimination capacity.

  10. Preliminary stabilisation of stormwater biofilters and loss of filter material.

    Science.gov (United States)

    Subramaniam, D N; Mather, P B

    Stabilisation affects performance of stormwater biofilters operating under intermittent wetting and drying, mainly due to wash-off of filter material. Understanding the dynamics of solids wash-off is crucial in designing stormwater biofilters. The current study analysed the dynamics of solids wash-off in stormwater biofilters and quantified the loss of solids from the filter. Four Perspex™ bioretention columns (94 mm internal diameter) were fabricated with a filter layer that contained 8% organic material and were fed with tap water with different numbers of antecedent dry days (0-40 day) at 100 mL/min. Samples were collected from the outflow and tested for particle size distribution and total solids and turbidity. Solids of particle size less than 50 microns were washed off from the filter during the stabilisation period, indicating that no sand particles were washed off. The very first event after commissioning the filter resulted in the highest wash-off of solids (approximately 75 g of fines) while a significant drop in wash-off followed from the second event. An empirical model fitted to the data showed that preliminary stabilisation of a filter occurs in the first three events, during which almost 25% of fines are lost from the filter.

  11. ASSESSMENT OF ODOUR EMISSIONS FROM AN OPEN BIOFILTER

    Directory of Open Access Journals (Sweden)

    Marlon Brancher

    2014-12-01

    Full Text Available Odour annoyances are considered a major cause of public complaints to regulatory agencies regarding air quality and represent a growing social problem, especially in industrialized countries. In view of the need to diagnose odour sources for control and mitigation of possible impacts on communities, was assessed, through a case study, the odorous emissions from an open biofilter. The equipment was responsible for gas treatment generated in the wastewater plant treatment of a textile industry. Sampling was conducted in the inlet duct of the biofilter using direct sampling and on the emission surface (output using a hood (VDI 3477:2004. Samples were stored in plastic bags manufactured in polyvinyl fluoride (Tedlar® and transported to the laboratory, where the odour concentration (in UO m-3 was determined based on the dynamic olfactometry dilution procedure (EN 13725:2003. To calculate the odour emission rate (OER (in UO h-1, the volumetric flow rate (in m3 h-1 was measured in the inlet duct of the biofilter. The values obtained for the efficiency and the OER were 98.7 % and 0.34 x 106 UO h-1, respectively. Comparing the efficiency value with the criterion established by Article 12 of Resolution SEMA No 054:2006 (State of Paraná, Brazil, adopted as reference, the biofiltration system meets the minimum efficiency rating of 85 % required in removing odour.

  12. Livestock air treatment using PVA-coated powdered activated carbon biofilter

    Science.gov (United States)

    The efficacy of polyvinyl alcohol (PVA) biofilters was studied using bench-scale biofilters and air from aerobically-treated swine manure. The PVA-coated powdered activated carbon particles showed excellent properties as a biofiltration medium: water holding capacity of 1.39 g H2O/g-dry PVA; wet por...

  13. Linking performance to microbiology in biofilters treating dimethyl sulphide in the presence and absence of methanol.

    Science.gov (United States)

    Hayes, Alexander C; Zhang, Yuefeng; Liss, Steven N; Allen, D Grant

    2010-01-01

    The performance and microbiology of two inorganic biofilters treating dimethyl sulphide (DMS) in the presence and absence of methanol was investigated. Addition of methanol was shown to result in an increase in DMS removal for methanol loadings below 90 g MeOH per cubic metre per hour with the optimal methanol loading around 10-15 g MeOH per cubic metre per hour for a DMS loading of 3.4 g DMS per cubic metre per hour, a fivefold increase in the DMS removal rate compared to the biofilter treating DMS alone. Microbial community analysis revealed that the addition of methanol led to a significant increase of up to an order of magnitude in the abundance of Hyphomicrobium spp. in the biofilter co-treating DMS and methanol compared to the biofilter treating DMS alone, whilst there was no significant difference in the abundance of Thiobacillus spp. between the two biofilters. Given the behaviour of the biofilter co-treating DMS and methanol, the magnitude of the increase in Hyphomicrobium spp. in the biofilter co-treating DMS and methanol and the ability of Hyphomicrobium spp. to use both methanol and DMS as growth substrates, it was concluded that Hyphomicrobium spp. were the microorganisms responsible for the bulk of the DMS degradation in the biofilter co-treating DMS and methanol.

  14. Comparative studies on toluene removal and pressure drop in biofilters using different packing materials.

    Science.gov (United States)

    Ryu, Hee Wook; Kim, So Jung; Cho, Kyung Suk

    2010-05-01

    To select the best available packing material for malodorous organic gases such as toluene and benzene, biofilter performance was compared in biofilters employed different packing materials including porous ceramic (celite), Jeju scoria (lava), a mixture of granular activated carbon (GAC) and celite (GAC/celite), and cubic polyurethane foam (PU). A toluene-degrading bacterium, Stenotrophomonas maltophilia T3-c, was used as the inoculum. The maximum elimination capacities in the celite, lava, and GAC/celite biofilters were 100, 130, and 110 gm(-3) hr(-1), respectively. The elimination capacity for the PU biofilter was approximately 350 g m(-3) hr(-1) at an inlet loading of approximately 430 g m(-3) hr(-1), which was 2 to 3.5 times higher than for the other biofilters. The pressure drop gradually increased in the GAC/ celite, celite and lava biofilters after 23 day due to bacterial over-growth, and the toluene removal efficiency remarkably decreased with increasing pressure drop. Backwashing method was not effective for the control of biomass in these biofilters. In the PU biofilter however, backwashing allowed maintenance of a pressure drop of 1 to 3 mm H2O m(-1) and a removal efficiency of > 80%, indicating that the PU was the best packing material for toluene removal among the packing materials tested.

  15. Decolorization of the AO24 azo dye and reduction of toxicity and genotoxicity in trickling biofilters.

    Science.gov (United States)

    Garzóón-Zúñga, Marco A; Sandoval-Villasana, Ana M; Moeller-Chávez, Gabriela E

    2011-02-01

    Acid Orange 24 (AO24) dye was degraded in a trickling biofilter packed with peat and wood chips and inoculated with biomass from a petrochemical industry wastewater system. Different operating strategies were tested; in the first stage, two biofilters were operated independently--one non-aerated biofilter (passive) and the other with aeration-subsequently, the systems were operated serially, and effluent from the non-aerated biofilter was fed to the biofilter with aeration. This treatment train was used to test three different filtration velocities--0.141, 0.282, and 0.423 m/d. The results show that, when operating the systems with a dye charge of 0.035 kg AO24 m2/d and treating the effluent in a single step, good removal efficiencies of AO24 (95 and 89%), COD (63 and 53%), and acute toxicity (63 and 78%) were obtained in both biofilters (with and without air), although mutagenic and potentially carcinogenic intermediary compounds were not removed, because genotoxicity exhibits values higher than 2.0 units for the mutation rate. When using the non-aerated biofilter/aerated biofilter treatment train, it is possible to treat a dye charge 3 times greater (0.106 kg AO24 m2/d) and efficiently remove 98% AO24, 76% COD, 100% acute toxicity, and 100% genotoxicity, which indicates that, with this biological system, an advanced degree of biotransformation and mineralization of the azo dye AO24 is achieved.

  16. Information und Kommunikation

    Science.gov (United States)

    Wesoly, Michael; Ohlhausen, Peter; Bucher, Michael; Hichert, Rolf; Korge, Gabriele; Schnabel, Ulrich; Gairola, Arun; Reichwald, Ralf; Habicht, Hagen; Möslein, Kathrin; Schwarz, Torsten; Schönsleben, Paul; Scherer, Eric; Schloske, Alexander; Adlbrecht, Gerald; Federhen, Jens

    Wissen ist mittlerweile unverzichtbar für den entscheidenden Vorsprung auf dem Markt. Unabhängig davon, ob sich das Wissen in Innovationen, neuen Produkten und Dienstleistungen oder in der Verbesserung interner Unternehmensprozesse manifestiert: Wissen ist Treiber von Innovation, Wissen bringt Schnelligkeit und Wissen ist die Voraussetzung für Problemlösungen [40]. Wissensmanagement ist daher der Schlüssel für Unternehmenserfolg und bezeichnet den "bewussten und systematischen Umgang mit der Ressource Wissen und den zielgerichteten Einsatz von Wissen in der Organisation“ [6]. In dieser umfassenden Sichtweise ist Wissensmanagement ein Begriff, der Konzepte, Strategien und Methoden umfasst.

  17. Westliche und muslimische Geschlechter?

    Directory of Open Access Journals (Sweden)

    Stanislawa Paulus

    2008-11-01

    Full Text Available Mihçiyazgan geht der Frage nach wie Differenzen in männlichen und weiblichen Subjektkonstutionen im Westen und im Islam empirisch erfasst werden können. Hierbei verfolgt sie eine antiessentialitische Perspektive, in der sie sich zentral auf Judith Butler und Michel Foucault bezieht. Über beide hinausgehend entwickelt sie ein Modell pluraler Diskurse, mit dessen Hilfe kulturelle bedingte Geschlechterkonstruktionen verstehbar werden. Anhand einer Untersuchung von Interviews, in der sie interaktionsanalytische und diskursanalytische Herangehensweisen verbindet, macht sie unterschiedliche Zonen des Sagbaren und Unsagbaren in westlichen und muslimischen Geschlechterdiskursen sichtbar.

  18. Ingenieurgeologie: Grundlagen und Anwendung

    Science.gov (United States)

    Genske, Dieter D.

    Geplünderter Planet? Die Ingenieurgeologie ist ein junges, interdisziplinäres Fachgebiet. Es befasst sich mit der Wechselwirkung zwischen Geosphäre und Mensch. Der Autor stellt Georisiken vor und diskutiert die Folgen menschlicher Eingriffe in die Natur. Er thematisiert aktuelle Herausforderungen und entwirft nachhaltige Lösungskonzepte für verschiedene Problembereiche: z.B. Naturgefahren wie Hangrutschungen und Bergfälle, die Ausbeute natürlicher Ressourcen, Bau- und Sanierungsvorhaben. Fallbeschreibungen und ausgearbeitete Beispiele vertiefen das Verständnis für diesen neuen, zukunftsweisenden Zweig der Wissenschaft.

  19. Targets and results of the German Reactor Safety Program; Ziele und Ergebnisse der deutschen Reaktorsicherheitsforschung

    Energy Technology Data Exchange (ETDEWEB)

    Walte, F.; Schmitz, V.; Kroening, M. [FhG - IZFP, Saarbruecken (Germany)

    1999-08-01

    The results obtained so far by the first two austenitic weld research projects show that the approach taken was the right one, as the modelling work in connection with the pulse-echo testing techniques did in fact achieve enhancements in the ultrasonic inspection of austenitic welds. The tools developed are: Ray tracing, point source synthesis, and EFIT, and can be successfully applied for NDE of transverse-isotropic weld microstructures, as was shown by all verification experiments. The project tasks for EFIT simulation and verification of the ultrasonic test method applied to anisotropic, dissimilar welds are expected to be concluded towards the end of the project period. If these activities prove to be successful, too, there will be several examples available giving evidence of the feasibility and suitability of the tools for an optimisation of the test parameters. The results available to date have been obtained with tests at several welds, assuming flaw types such as root defects perpendicular to the surface, which were introduced into the specimens by notches. (orig./CB) [Deutsch] Die bisher in den beiden Austenit-Forschungsprojekten erzielten Ergebnisse zeigen, dass der Ansatz, durch Modellierung der Impulsechopruefung einen Beitrag zur Verbesserung der Ultraschallpruefung von austenitischen Schweissnaehten zu leisten, richtig war. Die Werkzeuge: - Ray Tracing, - Punktquellensynthese, und - EFIT sind fuer transversal-isotrope Schweissnahtgefuege entwickelt und verfuegbar. Alle bisher durchgefuehrten Verifikationsexperimente waren erfolgreich. Die EFIT-Simulation und Verifikation der Ultraschallpruefung der anisotropen, inhomogenen Schweissnaht steht jedoch noch aus, wird aber bis zum Ende des Projektes erfolgen. Wenn auch dies gelingt, ist exemplarisch an einigen Beispielen gezeigt, dass die o.g. Werkzeuge tauglich sind, durch Vorausrechnung reale Ultraschallpruefungen hinsichtlich der Pruefparameter zu optimieren. Die bisherigen Ergebnisse wurden

  20. Experimental and numerical examination of the unsteady flow in an axial turbine; Experimentelle und numerische Untersuchung der instationaeren Stroemung in einer Axialturbine

    Energy Technology Data Exchange (ETDEWEB)

    Gentner, C.

    2000-07-01

    Berechnung des Laufrades der Einfluss des Spaltstroms auf das Betriebsverhalten der Turbine untersucht. Durch den Vergleich der Ergebnisse aus Messung und Berechnung kann man Aussagen ueber die Leistungsfaehigkeit und die Grenzen der numerischen Modellierung gewinnen. Ausserdem geben die Resultate Hinweise fuer die Optimierung der Turbine bezueglich Wirkungsgrad und Kavitation. (orig.)

  1. [Characteristics of microbial community and operation efficiency in biofilter process for drinking water purification].

    Science.gov (United States)

    Xiang, Hong; Lü, Xi-Wu; Yang, Fei; Yin, Li-Hong; Zhu, Guang-Can

    2011-04-01

    In order to explore characteristics of microbial community and operation efficiency in biofilter (biologically-enhanced active filter and biological activated carbon filter) process for drinking water purification, Biolog and polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) techniques were applied to analyze the metabolic function and structure of microbial community developing in biofilters. Water quality parameters, such as NH; -N, NO; -N, permanganate index, UV254 and BDOC etc, were determined in inflow and outflow of biofilters for investigation of operation efficiency of the biofilters. The results show that metabolic capacity of microbial community of the raw water is reduced after the biofilters, which reflect that metabolically active microbial communities in the raw water can be intercepted by biofilters. After 6 months operation of biofilters, the metabolic profiles of microbial communities are similar between two kinds of biologically-enhanced active filters, and utilization of carbon sources of microbial communities in the two filters are 73.4% and 75.5%, respectively. The metabolic profiles of microbial communities in two biological activated carbon filters showed significant difference. The carbon source utilization rate of microbial community in granule-activated carbon filter is 79.6%, which is obviously higher than 53.8% of the rate in the columnar activated carbon filter (p water purification efficiency was not significant (p > 0.05). However, in biological activated carbon filters, granule-activated carbon is conducive to microbial growth and reproduction, and the microbial communities in the biofilter present high metabolic activities, and the removal efficiency for NH4(+)-N, permanganate index and BDOC is better than the columnar activated carbon filter(p < 0.05). The results also suggest that operation efficiency of biofilter is related to the metabolic capacity of microbial community in biofilter.

  2. Do benthic biofilters contribute to sustainability and restoration of the benthic environment impacted by offshore cage finfish aquaculture?

    Science.gov (United States)

    Aguado-Giménez, F; Piedecausa, M A; Carrasco, C; Gutiérrez, J M; Aliaga, V; García-García, B

    2011-08-01

    Benthic biofilters were deployed under a cage fish farm and in two reference locations to assess the influence of the farm on the biofilters and the surroundings, as well as to verify the usefulness of this technology as a mitigation tool. The biofilters underneath the farm recruited a fouling community practically identical to that of the control biofilters, which included a variety of trophic strategies. The former showed a higher 15N enrichment, indicating that fouling beneath the farm was benefiting from the farm waste. The waste retention efficiency was low (0.02 g N m(-2) month(-1)) beneath the farm. Benthic biofilters aggregated demersal wild fish around and within them. Pelagic wild fish also frequently used the biofilters beneath the farm, forming compact shoals around them. The increased complexity of the habitat below the fish farm enhanced biodiversity, but this improvement did not lead to the recovery of the sediments around the biofilters.

  3. Strahlungsmessung und Dosimetrie

    CERN Document Server

    Krieger, Hanno

    2013-01-01

    „Strahlungsquellen und Dosimetrie“ ist Teil einer Lehrbuchreihe zur Strahlungsphysik und zum Strahlenschutz. Der erste Teil befasst sich mit den physikalischen Grundlagen der Strahlungsdetektoren und der Strahlungsmessung. Im zweiten Teil werden die Konzepte und Verfahren der klinischen Dosimetrie dargestellt. Der dritte Abschnitt erläutert ausführlich die Dosisverteilungen der klinisch angewendeten Strahlungsarten. Im vierten Teil werden weitere Messaufgaben der Strahlungsphysik einschließlich der Messsysteme für die Bildgebung mit Röntgenstrahlung dargestellt. Neben den grundlegenden Ausführungen enthält dieser Band im laufenden Text zahlreiche Tabellen und Grafiken zur technischen und medizinischen Radiologie, die bei der praktischen Arbeit sehr hilfreich sein können und 199 Übungsaufgaben mit Lösungen zur Vertiefung der Inhalte. Für die zweite Auflage wurden die Darstellungen der Elektronen- und der Protonendosimetrie sowie der bildgebenden Verfahren mit Computertomografen deutlich erweit...

  4. Medikamentengabe und Psychotherapie

    OpenAIRE

    2013-01-01

    Psychopharmakotherapie ist ein möglicher Baustein in der multimodalen Behandlung kinder- und jugendpsychiatrischer Störungsbilder. Diese simple Aussage ist unumstritten. Dennoch haben im klinischen Alltag sowohl Eltern als auch Psychotherapeuten häufig erhebliche Bedenken, einem Kind ein Psychopharmakon zu verabreichen. Neben angemessenen Bedenken zu potenziellen Wechselwirkungen zwischen psychopharmakotherapie und Psychotherapie oder Unsicherheiten zu Wirkungen und Nebenwirkungen eines Psych...

  5. Digital Zeichnen und Malen

    Directory of Open Access Journals (Sweden)

    Christoph Kaindel

    2013-12-01

    Full Text Available Digitales Zeichnen und Malen hat gegenüber dem „analogen“ Vorteile wie auch Nachteile. In der folgenden, unvollständigen Liste stelle ich die technischen Vor- und Nachteile, die mir aufgefallen sind, gegenüber. Kommentare und Ergänzungen sind willkommen!

  6. Microbial response and elimination capacity in biofilters subjected to high toluene loadings.

    Science.gov (United States)

    Song, JiHyeon; Kinney, Kerry A

    2005-09-01

    Elimination capacity (EC) is frequently used as a performance and design criterion for vapor-phase biofilters without further verification of the microbial quantity and activity. This study was conducted to investigate how biofilters respond to high pollutant loadings and ultimately how this affects the EC of the biofilter. Two identical laboratory-scale biofilters were maintained at an initial toluene loading rate of 46 g m-3 h-1 for a period of 24 days. After the initial biofilm development stage, the loading rates were increased to 91 g m-3 h-1 and 137 g m-3 h-1, respectively. Following a short period of pseudo-steady state, toluene removal efficiencies rapidly declined in both biofilters, with a concurrent decline in both critical and maximum ECs. The decline was mainly due to deterioration in the biodegradation activity of the biofilm and a decline in the toluene-degrading bacterial population within the biofilm phase. The findings imply that high toluene loadings accelerated the deterioration in overall performance due to a rapid accumulation of inactive biomass. As a result, care must be used when relying on EC values for biofilter design and operational purposes, since the values do not appropriately reflect the temporal changes in biodegradation activity and active biomass quantities that can occur in biofilters subjected to high inlet loadings.

  7. Three-stage aged refuse biofilter for the treatment of landfill leachate

    Institute of Scientific and Technical Information of China (English)

    LI Hongjiang; ZHAO Youcai; SHI Lei; GU Yingying

    2009-01-01

    A field-scale aged refuse (AR) biofilter constructed in Shanghai Refuse Landfill, containing about 7 000 m3 aged refuse inside, was evaluated for its performance in the treatment of landfill leachate. This AR biofilter can be divided into three stages and can manage 50 m3 landfill leachate per day. The physical, chemical, and biological characteristics of AR were analyzed for evaluating the AR biofilter as leachate treatment host. The results revealed that over 87.8%--96.2% of COD and 96.9%--99.4% of ammonia nitrogen were removed by the three-stage AR biofilter when the influent leachate COD and ammonia nitrogen were 5 478-10 842 mg/L and 811-1 582 mg/L, respectively. The final effluent was inodorous and pale yellow with COD and ammonia nitrogen below 267--1,020 mg/L and 6--45 mg/L, respectively. The three-stage AR biofilter had efficient nitrification but relative poor denitrification capacity with a total nitrogen (TN) removal of 58%--73%. The external temperature of AR biofilter did not influence the total ammonia nitrogen removal significantly. It was concluded that the scale-up AR biofilter can work very well and can be a promising technology for the treatment of landfill leachate.

  8. The influence of temperature and salt on metal and sediment removal in stormwater biofilters.

    Science.gov (United States)

    Søberg, Laila C; Viklander, Maria; Blecken, Godecke-Tobias

    2014-01-01

    Stormwater biofilters are used to treat stormwater runoff. In countries with cold winter climates, biofilters are subject to low temperatures which, in some cases, are combined with potentially high salt concentrations from road de-icing, potentially affecting the biofilter's performance. Since stormwater biofilters have been developed without consideration of their critical winter use, a laboratory study was carried out to evaluate the performance of stormwater biofilters subjected to low and high temperatures, with and without salt. Both factors and their interaction had a significant effect on outflow concentrations and removal percentages. Salt had a negative impact on outflow concentrations, causing lower removal percentages for (especially dissolved) metals, this impact being most pronounced for Cu and Pb. The unrealistic combination of salt with high temperature seemed to further amplify the negative impacts of salt despite the fact that temperature alone did not cause significant differences in outflow concentrations and removal percentages. Still, biofilters showed the ability to treat stormwater efficiently under the simulated winter conditions; outflow concentrations for total metals as a minimum met the class 4 threshold value defined in the Swedish freshwater quality guidelines, while inflow concentrations clearly exceeded the threshold value for class 5. The relatively coarse filter material (which is recommended to facilitate infiltration during winter) did not seem to exacerbate biofilter performance.

  9. Ethylene removal evaluation and bacterial community analysis of vermicompost as biofilter material.

    Science.gov (United States)

    Fu, Yuming; Shao, Lingzhi; Liu, Hui; Tong, Ling; Liu, Hong

    2011-08-30

    Biofiltration of ethylene provides an environmentally friendly and economically beneficial option relative to physical/chemical removal, where selection of appropriate bed material is crucial. Here the vermicompost with indigenous microorganisms as bed material was evaluated for ethylene removal through batch test and biofilter experiment. Temporal and spatial dynamics of bacterial community in the vermicompost-biofilter under different ethylene loads were characterized by culture and denaturing gradient gel electrophoresis (DGGE) methods. The results showed that ethylene was effectively degraded by the vermicompost under conditions of 25-50% moisture content and 25-35°C temperature. The vermicompost-biofilter achieved nearly 100% ethylene removal up to an inlet load of 11mg m(-3)h(-1). Local nitrogen lack of the vermicompost in the biofilter was observed over operation time, but the change of pH was slight. DGGE analysis demonstrated that the bacterial abundance and community structure of vermicompost-biofilter varied with the height of biofilter under different ethylene loads. Pseudomonads and Actinobacteria were predominant in the biofilter throughout the whole experiment.

  10. Soil-biofilters for elimination of xenobiotics from wastewaters

    DEFF Research Database (Denmark)

    Bester, Kai; Schäfer, Daniel; Janzen, Niklas

    The presence of xenobiotics in surface waters and ground water is not wanted in general and in detail regulated by a multitude of international and national regulations. However, xenobiotic compounds are emitted with the regular treated waste water into surface waters, as current waste water...... and other components with low cost soil biofilter techniques suited for on-site decentralised treatment of storm waters and combined sewer overflows. On the other hand the same systems and compounds were tested in for polishing treated waste water in respect of further elimination of xenobiotic compounds....

  11. Development of new methods for the modeling of technical systems and result evaluation for reactor safety simulation codes. Modeling, simulation models; Entwicklung neuer Methoden zur Modellierung technischer Systeme und zur Ergebnisauswertung fuer Simulationsprogramme der Reaktorsicherheit. Modellierung, Simulationsprogramme

    Energy Technology Data Exchange (ETDEWEB)

    Cester, Francesco; Deitenbeck, Helmuth; Kuentzel, Matthias; Scheuer, Josef; Voggenberger, Thomas

    2015-04-15

    The overall objective of the project is to develop a general simulation environment for program systems used in reactor safety analysis. The simulation environment provides methods for graphical modeling and evaluation of results for the simulation models. The terms of graphical modeling and evaluation of results summarize computerized methods of pre- and postprocessing for the simulation models, which can assist the user in the execution of the simulation steps. The methods comprise CAD (''Computer Aided Design'') based input tools, interactive user interfaces for the execution of the simulation and the graphical representation and visualization of the simulation results. A particular focus was set on the requirements of the system code ATHLET. A CAD tool was developed that allows the specification of 3D geometry of the plant components and the discretization with a simulation grid. The system provides inter-faces to generate the input data of the codes and to export the data for the visualization software. The CAD system was applied for the modeling of a cooling circuit and reactor pressure vessel of a PWR. For the modeling of complex systems with many components, a general purpose graphical network editor was adapted and expanded. The editor is able to simulate networks with complex topology graphically by suitable building blocks. The network editor has been enhanced and adapted to the modeling of balance of plant and thermal fluid systems in ATHLET. For the visual display of the simulation results in the local context of the 3D geometry and the simulation grid, the open source program ParaView is applied, which is widely used for 3D visualization of field data, offering multiple options for displaying and ana-lyzing the data. New methods were developed, that allow the necessary conversion of the results of the reactor safety codes and the data of the CAD models. The trans-formed data may then be imported into ParaView and visualized. The application of 3D visualization shows advantages in transient analyses with very detailed discretization. This is especially true for the analysis of phenomena with strong local differences and the validation of multi-dimensional models.

  12. Performance of low pH biofilters treating a paint solvent mixture: Continuous and intermittent loading

    Energy Technology Data Exchange (ETDEWEB)

    Qi Bing [Department of Civil and Environmental Engineering, Louisiana State University, 3418G CEBA Building, Baton Rouge, LA 70803 (United States); Moe, William M. [Department of Civil and Environmental Engineering, Louisiana State University, 3418G CEBA Building, Baton Rouge, LA 70803 (United States)]. E-mail: moemwil@lsu.edu

    2006-07-31

    Two biofilters packed with a reticulated polyurethane foam medium were inoculated with a compost-derived enrichment culture grown under acidic conditions (pH 3.0) and then operated over a period lasting 63 days. Both biofilters were supplied with a humidified gas stream containing a five-component mixture of acetone, methyl ethyl ketone, toluene, ethylbenzene, and p-xylene at a total VOC loading rate 80.3 g m{sup -3} h{sup -1} to simulate treatment of air emissions resulting from manufacture of reformulated paint. One biofilter was operated under continuous loading conditions and the other received intermittent loading with contaminants supplied only 8 h/day. Nutrient solution with pH 3.0 was supplied approximately once per week to provide nitrogen and other nutrients. Data are presented which demonstrate that undefined mixed cultures acclimated at low pH can successfully treat paint solvent mixtures in biofilters. The biofilter receiving continuous loading reached high overall removal efficiency (greater than 90% overall removal) 3 weeks after startup, and performance increased over time reaching overall removal in the range of 97-99% after 50 days. Performance of the intermittently loaded biofilter developed more slowly, requiring 6 weeks to stabilize at an overall removal efficiency in excess of 90%. In both biofilters, ketone components were more rapidly degraded than aromatic components, and removal of aromatic compounds was somewhat unstable even after 2 months of biofilter operation. Scanning electron microscopy (SEM) revealed that fungi dominated the microbial populations in both biofilters.

  13. Temporal and spatial stability of ammonia-oxidizing archaea and bacteria in aquarium biofilters.

    Science.gov (United States)

    Bagchi, Samik; Vlaeminck, Siegfried E; Sauder, Laura A; Mosquera, Mariela; Neufeld, Josh D; Boon, Nico

    2014-01-01

    Nitrifying biofilters are used in aquaria and aquaculture systems to prevent accumulation of ammonia by promoting rapid conversion to nitrate via nitrite. Ammonia-oxidizing archaea (AOA), as opposed to ammonia-oxidizing bacteria (AOB), were recently identified as the dominant ammonia oxidizers in most freshwater aquaria. This study investigated biofilms from fixed-bed aquarium biofilters to assess the temporal and spatial dynamics of AOA and AOB abundance and diversity. Over a period of four months, ammonia-oxidizing microorganisms from six freshwater and one marine aquarium were investigated at 4-5 time points. Nitrogen balances for three freshwater aquaria showed that active nitrification by aquarium biofilters accounted for ≥ 81-86% of total nitrogen conversion in the aquaria. Quantitative PCR (qPCR) for bacterial and thaumarchaeal ammonia monooxygenase (amoA) genes demonstrated that AOA were numerically dominant over AOB in all six freshwater aquaria tested, and contributed all detectable amoA genes in three aquarium biofilters. In the marine aquarium, however, AOB outnumbered AOA by three to five orders of magnitude based on amoA gene abundances. A comparison of AOA abundance in three carrier materials (fine sponge, rough sponge and sintered glass or ceramic rings) of two three-media freshwater biofilters revealed preferential growth of AOA on fine sponge. Denaturing gel gradient electrophoresis (DGGE) of thaumarchaeal 16S rRNA genes indicated that community composition within a given biofilter was stable across media types. In addition, DGGE of all aquarium biofilters revealed low AOA diversity, with few bands, which were stable over time. Nonmetric multidimensional scaling (NMDS) based on denaturing gradient gel electrophoresis (DGGE) fingerprints of thaumarchaeal 16S rRNA genes placed freshwater and marine aquaria communities in separate clusters. These results indicate that AOA are the dominant ammonia-oxidizing microorganisms in freshwater aquarium

  14. Temporal and spatial stability of ammonia-oxidizing archaea and bacteria in aquarium biofilters.

    Directory of Open Access Journals (Sweden)

    Samik Bagchi

    Full Text Available Nitrifying biofilters are used in aquaria and aquaculture systems to prevent accumulation of ammonia by promoting rapid conversion to nitrate via nitrite. Ammonia-oxidizing archaea (AOA, as opposed to ammonia-oxidizing bacteria (AOB, were recently identified as the dominant ammonia oxidizers in most freshwater aquaria. This study investigated biofilms from fixed-bed aquarium biofilters to assess the temporal and spatial dynamics of AOA and AOB abundance and diversity. Over a period of four months, ammonia-oxidizing microorganisms from six freshwater and one marine aquarium were investigated at 4-5 time points. Nitrogen balances for three freshwater aquaria showed that active nitrification by aquarium biofilters accounted for ≥ 81-86% of total nitrogen conversion in the aquaria. Quantitative PCR (qPCR for bacterial and thaumarchaeal ammonia monooxygenase (amoA genes demonstrated that AOA were numerically dominant over AOB in all six freshwater aquaria tested, and contributed all detectable amoA genes in three aquarium biofilters. In the marine aquarium, however, AOB outnumbered AOA by three to five orders of magnitude based on amoA gene abundances. A comparison of AOA abundance in three carrier materials (fine sponge, rough sponge and sintered glass or ceramic rings of two three-media freshwater biofilters revealed preferential growth of AOA on fine sponge. Denaturing gel gradient electrophoresis (DGGE of thaumarchaeal 16S rRNA genes indicated that community composition within a given biofilter was stable across media types. In addition, DGGE of all aquarium biofilters revealed low AOA diversity, with few bands, which were stable over time. Nonmetric multidimensional scaling (NMDS based on denaturing gradient gel electrophoresis (DGGE fingerprints of thaumarchaeal 16S rRNA genes placed freshwater and marine aquaria communities in separate clusters. These results indicate that AOA are the dominant ammonia-oxidizing microorganisms in freshwater

  15. Temporal and Spatial Stability of Ammonia-Oxidizing Archaea and Bacteria in Aquarium Biofilters

    KAUST Repository

    Bagchi, Samik

    2014-12-05

    Nitrifying biofilters are used in aquaria and aquaculture systems to prevent accumulation of ammonia by promoting rapid conversion to nitrate via nitrite. Ammonia-oxidizing archaea (AOA), as opposed to ammonia-oxidizing bacteria (AOB), were recently identified as the dominant ammonia oxidizers in most freshwater aquaria. This study investigated biofilms from fixed-bed aquarium biofilters to assess the temporal and spatial dynamics of AOA and AOB abundance and diversity. Over a period of four months, ammonia-oxidizing microorganisms from six freshwater and one marine aquarium were investigated at 4–5 time points. Nitrogen balances for three freshwater aquaria showed that active nitrification by aquarium biofilters accounted for ≥81–86% of total nitrogen conversion in the aquaria. Quantitative PCR (qPCR) for bacterial and thaumarchaeal ammonia monooxygenase (amoA) genes demonstrated that AOA were numerically dominant over AOB in all six freshwater aquaria tested, and contributed all detectable amoA genes in three aquarium biofilters. In the marine aquarium, however, AOB outnumbered AOA by three to five orders of magnitude based on amoA gene abundances. A comparison of AOA abundance in three carrier materials (fine sponge, rough sponge and sintered glass or ceramic rings) of two three-media freshwater biofilters revealed preferential growth of AOA on fine sponge. Denaturing gel gradient electrophoresis (DGGE) of thaumarchaeal 16S rRNA genes indicated that community composition within a given biofilter was stable across media types. In addition, DGGE of all aquarium biofilters revealed low AOA diversity, with few bands, which were stable over time. Nonmetric multidimensional scaling (NMDS) based on denaturing gradient gel electrophoresis (DGGE) fingerprints of thaumarchaeal 16S rRNA genes placed freshwater and marine aquaria communities in separate clusters. These results indicate that AOA are the dominant ammonia-oxidizing microorganisms in freshwater aquarium

  16. Phaeobacter grown in biofilters: a new strategy for the control of Vibrionaceae in aquaculture

    DEFF Research Database (Denmark)

    Prol García, María Jesús; Gomez, Marina; Sanchez, Lorenzo;

    2014-01-01

    Growth, biofilm formation, antagonism and residence time in green seawater tanks maintained under fish rearing conditions of Phaeobacter 27-4 were studied in commercial biofilters made from plastic, sintered glass and ceramic. Phaeobacter reached 10(8)-10(9)CFUcm(-3) and formed rosettes in all...... in one-two Log, showing 10(7)CFUmL(-1) after 24h. Phaeobacter also diminished biofilters colonization by the pathogens, both in seawater and in MB. Phaeobacter residence time in green seawater tanks maintained under fish rearing conditions was longer with sintered glass and ceramic biofilters. The latest...

  17. Romanistik und gender studies

    Directory of Open Access Journals (Sweden)

    Susanne Schlünder

    2000-11-01

    Full Text Available Die beiden Bände bieten ein breites Spektrum von Beiträgen zur französischen, italienischen und spanischen Literaturwissenschaft. Gedankliche Grundlage der im einzelnen unterschiedlichen Ansätze und Zielsetzungen ist ein im Anschluß an Judith Butler gender-reflektierendes, diskursives Konzept von Geschlecht, dessen wissenschaftsgeschichtliche Herleitung und Perspektiven Renate Kroll einleitend darlegt. Die einzelnen Artikel beschäftigen sich zum einen mit literarischen Strategien, die Schriftstellerinnen vom Mittelalter bis zur Gegenwart erprobt haben, und hinterfragen dabei die Rolle weiblicher Autoren in Literaturgeschichte und Literaturgeschichtsschreibung. Zum anderen widmen sie sich den literarischen Inszenierungs- und Repräsentationsformen von Weiblichkeit und stellen darüber einen Bezug zur Lebenswelt der behandelten Autorinnen her.

  18. Schwangerschaftshypertonie: Therapie und Nachsorge

    Directory of Open Access Journals (Sweden)

    Homuth V

    2008-01-01

    Full Text Available Kurzfassung: Hypertensive Schwangerschaftserkrankungen komplizieren mehr als 10 % aller Schwangerschaften weltweit. Klinisch am bedeutsamsten sind die durch Hypertonie und Proteinurie nach der 20. Schwangerschaftswoche definierte schwangerschaftsinduzierte Präeklampsie und Pfropfpräeklampsie, insbesondere deren schwerste Verlaufsformen Eklampsie und HELLP-Syndrom. Sie gehören global unverändert zu den führenden Ursachen für fetale, neonatale und mütterliche Morbidität und Mortalität. Ihre Ätiologie ist unbekannt und daher ist mit Ausnahme der Beendigung der Schwangerschaft eine kausale Therapie nicht möglich. Insbesondere bleibt eine antihypertensive Therapie hinsichtlich der fetalen Entwicklung problematisch und sollte zur Vermeidung mütterlicher kardiovaskulärer Komplikationen erst bei Blutdruckwerten ≥ 170/110 mmHg begonnen werden, bei vorbestehendem Hochdruck oder Pfropfkonstellation (präexistente Nierenerkrankung, Diabetes mellitus bereits ab Blutdruckwerten von ≥ 160/ 100 mmHg. Zu beachten ist dabei die nur geringe Auswahl in der Schwangerschaft einsetzbarer Antihypertensiva, die sich im Wesentlichen auf Methyldopa, und bereits eingeschränkt auf den Betablocker Metoprolol sowie Dihydralazin und den Kalziumantagonisten Nifedipin begrenzt. Eine der wichtigsten Aufgaben nach der Entbindung ist die Gewährleistung und Förderung des Stillens. Aufgrund ausreichender medikamentöser Alternativen ist ein Abstillen wegen einer antihypertensiven Therapie nicht indiziert. Ergebnisse aktueller Untersuchungen zeigen, dass eine Hypertonie in der Schwangerschaft und ihre Komplikationen Frühgeburtlichkeit und vermindertes Geburtsgewicht einen bedeutsamen Risikofaktor für das Auftreten kardiovaskulärer Erkrankungen, wie Herzinfarkt und Schlaganfall, im späteren Leben darstellen. Daher sind für davon Betroffene frühzeitige Maßnahmen zur kardiovaskulären Prävention und lebenslangen Verlaufskontrolle zu fordern.

  19. Dimethylamine biodegradation by mixed culture enriched from drinking water biofilter.

    Science.gov (United States)

    Liao, Xiaobin; Chen, Chao; Zhang, Jingxu; Dai, Yu; Zhang, Xiaojian; Xie, Shuguang

    2015-01-01

    Dimethylamine (DMA) is one of the important precursors of drinking water disinfection by-product N-nitrosodimethylamine (NDMA). Reduction of DMA to minimize the formation of carcinogenic NDMA in drinking water is of practical importance. Biodegradation plays a major role in elimination of DMA pollution in the environment, yet information on DMA removal by drinking water biofilter is still lacking. In this study, microcosms with different treatments were constructed to investigate the potential of DMA removal by a mixed culture enriched from a drinking water biofilter and the effects of carbon and nitrogen sources. DMA could be quickly mineralized by the enrichment culture. Amendment of a carbon source, instead of a nitrogen source, had a profound impact on DMA removal. A shift in bacterial community structure was observed with DMA biodegradation, affected by carbon and nitrogen sources. Proteobacteria was the predominant phylum group in DMA-degrading microcosms. Microorganisms from a variety of bacterial genera might be responsible for the rapid DMA mineralization.

  20. Geschlechtsrolle und psychische Erkrankung

    Directory of Open Access Journals (Sweden)

    Möller-Leimkühler AM

    2005-01-01

    Full Text Available Aus der Perspektive der historisch/gesellschaftlich konstruierten sozialen Geschlechtsrollen wird anhand sozialepidemiologischer Daten die Frage erörtert, welche Zusammenhänge zwischen den traditionellen Geschlechtsrollen und dem Auftreten psychischer Störungen bestehen. Die Geschlechtsrolle stellt ein zentrales Bindeglied zwischen personaler und sozialer Identität sowie gesellschaftlichen Bedingungen dar. Hinter den geschlechtsspezifisch unterschiedlichen Störungsprofilen bei Männern und Frauen verbirgt sich eine Reihe von Risikofaktoren, die jeweils andere Konsequenzen für die Geschlechter haben. Diese Risikofaktoren sind einerseits mit der sozialen Lage verknüpft (Rollenvielfalt vs. Rollenreduktion, Arbeitslosigkeit, berufliche Gratifikationskrisen, Ehe/Trennung, andererseits entstehen sie über handlungsrelevante soziale Stereotypisierungen ("Gender bias"“ in medizinischen Institutionen. Gesundheitsrisiken sind nicht nur extern mit der Geschlechtsrolle verbunden, sondern können sich auch über die Internalisierung traditioneller Weiblichkeits- und Männlichkeitsnormen entwickeln, die zu geschlechtsspezifischen Verarbeitungsmustern psychosozialer Belastungen führen. So fördern geschlechtstypische Gesundheits- und Krankheitskonzepte, geschlechtstypische Belastungskonstellationen und Defizite normativer Sozialisation bei Frauen eher affektive und psychosomatische Störungen, bei Männern eher Alkoholabhängigkeit, Persönlichkeitsstörungen, Gewaltdelikte und Suizid. Die dargestellten Zusammenhänge zwischen sozialem Geschlecht und psychischen Störungen haben zahlreiche Implikationen für eine geschlechtersensible Forschung, Therapie und Gesundheitspolitik.

  1. Photonik: Grundlagen, Technologie und Anwendung

    Science.gov (United States)

    Hering, Ekbert; Martin, Rolf

    Photonik gilt als eine der Zukunftstechnologien mit starkem Bezug zu zahlreichen Technologiefeldern. Dem trägt das Buch Rechnung. Nach einer Einführung in die physikalischen und technischen Grundlagen geben die Autoren einen Einblick in die Fertigung optischer Komponenten und Systeme. Es folgen optische Sensortechnik und Meßtechnik und die Anwendungen in Informations- und Kommunikationstechnik sowie in der Produktionstechnik, in der Medizin und im Konsumgüterbereich.

  2. Pyrosequencing Analysis of Bench-Scale Nitrifying BiofiltersRemoving Trihalomethanes

    Science.gov (United States)

    The bacterial biofilm communities in four nitrifying biofilters degrading regulated drinking water trihalomethanes were characterized by 454 pyrosequencing. The three most abundant phylotypes based on total diversity were Nitrosomonas (70%), Nitrobacter (14%), and Chitinophagace...

  3. Styrene removal from wate gas by the fungus Exophiala Jeanselmei in a biofilter

    NARCIS (Netherlands)

    Cox, Hubertus Henricus Jacobus

    1995-01-01

    Styrene is an environmental pollutant, emitted in large quantities to the atmosphere by various industrial sectors. Legislation requires industry to reduce the emission of styrene. One option to purify industrial waste gases is biological treatment in biofilters. ... Zie: Summary

  4. Effects of jetties on semiterrestrial areas - macrozoobenthos and carabidocoenosis of the jetty fields; Auswirkungen von Buhnen auf semiterrestrische Flaechen - Makrozoobenthos und Carabidozoenose der Buhnenfelder

    Energy Technology Data Exchange (ETDEWEB)

    Thiel, C. [Marburg Univ. (Germany). Inst. fuer Biologie und Spezielle Zoologie; Dirksen, M.T.; Wunsch, E.; Assmuth, T.

    2000-07-01

    Floodlands of big rivers today are areas that have been affected by river development measures. The fauna of these areas had to adapt, not in terms of a modification of its ecological needs but in terms of a change in the composition of biocoenoses as a result of many ecological influencing variables. This project attempted a modelling of the dominant environmental variables, i.e. morphodynamics and hydrodynamics, and a simulation of the reaction of biocoenoses on the changing environmental conditions in the jetty fields. The project is part of the 'Elberiver ecology' research association and is funded by the BMBF. [German] Die Tieflandregionen groesserer Fluesse sind heute auf weiten Strecken von flussbaulichen Massnahmen gepraegt. Die Lebensgemeinschaften der urspruenglichen Auen haben auf die anthropogen ueberformten Gegebenheiten reagiert. Das bedeutet nicht etwa, dass sich die Arten der urspruenglichen Auenfauna in ihren oekologischen Anspruechen adaptiert haetten. Vielmehr wird eine Veraenderung der Zusammensetzung der Biozoenosen deutlich. Bedingt wird die Veraenderung der Biozoenosen in den aquatischen und semiterrestrischen Bereichen des Gewaessers von einer Vielzahl von Umweltvariablen. Die Modellierung der dominierenden Umweltvariablen Morpho- und Hydrodynamik sowie die Simulation der Reaktionen der Lebensgemeinschaften auf die Aenderung der Verhaeltnisse im Buhnenfeld ist Inhalt unseres interdisziplinaeren Projektes. Dieses ist eingebettet in den Forschungsverbund Elbe-Oekologie und wird vom BMBF gefoerdert. (orig.)

  5. Metallurgical and process engineering fundamentals of cast iron melting in a cokeless cupola furnace. Final report; Metallurgische und verfahrenstechnische Grundlagen des Schmelzens von Gusseisen im kokslosen Kupolofen (KLKO). Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Schuermann, E.; Pluschkell, W.; Scholz, R.; Davies, M.

    2000-07-01

    The development of an adiabatically analytical and numerically verifiable energetic process model is described which takes account of the influence of all relevant process parameters. The project was to provide a basis for assessing the performance of a real plant (Laufach) and for developing an adiabatic numerical model. The methods and results are described in detail. [German] In dem Bericht wird die Entwicklung eines adiabat analytischen und numerisch tragfaehigen energetischen Prozessmodells vorgestellt, welches den Einfluss der wesentlichen Betriebsgroessen wie z.B. Erdgasvolumenstrom, Schmelzleistung, Abstichtemperatur, Laenge der Ueberhitzungszone, Laenge der Vorwaermzone bei ausreichend hohem Ofen, spezifische Oberflaeche des Einsatzgutes auf die Schmelzleistung des KLKO beschreibt. Ziel ist es, insgesamt das Betriebsverhalten einer realen Anlage in Laufach (Versuchsofen) zu beurteilen und nachzuempfinden sowie erste Betriebsoptimierungen durchzufuehren. Dazu wird zunaechst ein adiabates Prozessmodell (geschlossene Loesung) und danach ein adiabates numerisches Prozessmodell als Voraussetzung zur Beruecksichtigung von Abbrandreaktionen, Zersetzungsreaktionen usw. (keine geschlossene Loesung moeglich) entwickelt. Fuer die Modellierung wird der Ofen in die 4 Zonen Vorwaermzone, Schmelzzone, Ueberhitzungszone und Brennraum aufgeteilt. Der Gesamtvorgang im Ofen wird auf der Basis einer Hintereinanderschaltung dieser vier Gegenstrom-Rekuperatoren modelliert. (orig.)

  6. Effect of continuous ozone injection on performance and biomass accumulation of biofilters treating gaseous toluene.

    Science.gov (United States)

    Xi, Jinying; Saingam, Prakit; Gu, Feng; Hu, Hong-Ying; Zhao, Xuefei

    2015-01-01

    Biofilters treating high-concentration gaseous volatile organic compounds (VOC) can be subject to bed clogging induced by excess biomass accumulation. In this study, O3 was continuously injected into biofilters to control biomass. Its effects on the performance of the biofilters and on biomass accumulation were investigated. Four identical biofilters designed to treat gaseous toluene were operated for 70 days, and three of them were continuously injected with O3 at different concentrations (from 80 to 320 mg/m(3)). The results showed that continuous O3 injection could effectively keep the bed pressure drop stable and had no adverse effect on toluene removal when O3 concentrations were 180-220 mg/m(3). The maximum toluene elimination capacity of the four biofilters was 140 g-toluene/m(3)/h, and the bed pressure drop of the biofilter fed with 180-220 mg/m(3) O3 remained below 3 mmH2O/m throughout the operation period. The biomass accumulation rates of the three biofilters with O3 at 80-320 mg/m(3) were lowered by 0.15-0.25 g/L/day compared with the biofilter without O3. The decreases in biomass accumulation resulted in higher void fractions of the filter beds with O3 injection. Carbon balance analysis indicated that CO2 production had increased while biomass accumulation and leachate waste production decreased in response to O3 injection. Based on the experimental results, it was concluded here that continuous O3 injection can reduce increases in bed pressure effectively, preserve VOC removal capacity, and prevent production of extra leachate waste.

  7. Effect of continuous ozone injection on performance and biomass accumulation of biofilters treating gaseous toluene.

    Science.gov (United States)

    Xi, Jinying; Saingam, Prakit; Gu, Feng; Hu, Hong-Ying; Zhao, Xuefei

    2014-11-01

    Biofilters treating high-concentration gaseous volatile organic compounds (VOC) can be subject to bed clogging induced by excess biomass accumulation. In this study, O3 was continuously injected into biofilters to control biomass. Its effects on the performance of the biofilters and on biomass accumulation were investigated. Four identical biofilters designed to treat gaseous toluene were operated for 70 days, and three of them were continuously injected with O3 at different concentrations (from 80 to 320 mg/m(3)). The results showed that continuous O3 injection could effectively keep the bed pressure drop stable and had no adverse effect on toluene removal when O3 concentrations were 180-220 mg/m(3). The maximum toluene elimination capacity of the four biofilters was 140 g-toluene/m(3)/h, and the bed pressure drop of the biofilter fed with 180-220 mg/m(3) O3 remained below 3 mmH2O/m throughout the operation period. The biomass accumulation rates of the three biofilters with O3 at 80-320 mg/m(3) were lowered by 0.15-0.25 g/L/day compared with the biofilter without O3. The decreases in biomass accumulation resulted in higher void fractions of the filter beds with O3 injection. Carbon balance analysis indicated that CO2 production had increased while biomass accumulation and leachate waste production decreased in response to O3 injection. Based on the experimental results, it was concluded here that continuous O3 injection can reduce increases in bed pressure effectively, preserve VOC removal capacity, and prevent production of extra leachate waste.

  8. Psychiatrische Erkrankungen und Wirtschaftskrisen

    Directory of Open Access Journals (Sweden)

    Berghofer G

    2014-01-01

    Full Text Available Es besteht ein enger Zusammenhang von wirtschaftlichen Krisen und erhöhten Raten an Arbeitslosigkeit mit psychischen Erkrankungen wie Depressionen, Angstzuständen, Schlafstörungen und Alkoholismus sowie erhöhten Suizidraten. Gleichzeitig gibt es wirkungsvolle Maßnahmen, diesen schädlichen Gesundheitsauswirkungen von Wirtschaftskrisen effektiv entgegenzuwirken. Dazu gehören soziale und finanzielle Absicherungsprogramme, arbeitsmarktpolitische Förderangebote, Unterstützungsmaßnahmen für Familien und Entschuldungsprogramme. In Wirtschaftskrisen vorgenommene Kürzungen im Gesundheitswesen führen hingegen zu einer Verschlechterung der gesundheitlichen Versorgung und längerfristig zu erhöhten Gesundheitskosten. Um negativen gesundheitlichen Auswirkungen von Wirtschaftskrisen effektiv vorzubeugen, sollte daher präventiv in den Ausbau psychosozialer Angebote und medizinischer wie therapeutischer Versorgungseinrichtungen mit niederschwelligem Zugang investiert werden.

  9. Biological removal of gaseous ammonia in biofilters: space travel and earth-based applications

    Science.gov (United States)

    Joshi, J. A.; Hogan, J. A.; Cowan, R. M.; Strom, P. F.; Finstein, M. S.; Janes, H. W. (Principal Investigator)

    2000-01-01

    Gaseous NH3 removal was studied in laboratory-scale biofilters (14-L reactor volume) containing perlite inoculated with a nitrifying enrichment culture. These biofilters received 6 L/min of airflow with inlet NH3 concentrations of 20 or 50 ppm, and removed more than 99.99% of the NH3 for the period of operation (101, 102 days). Comparison between an active reactor and an autoclaved control indicated that NH3 removal resulted from nitrification directly, as well as from enhanced absorption resulting from acidity produced by nitrification. Spatial distribution studies (20 ppm only) after 8 days of operation showed that nearly 95% of the NH3 could be accounted for in the lower 25% of the biofilter matrix, proximate to the port of entry. Periodic analysis of the biofilter material (20 and 50 ppm) showed accumulation of the nitrification product NO3- early in the operation, but later both NO2- and NO3- accumulated. Additionally, the N-mass balance accountability dropped from near 100% early in the experiments to approximately 95 and 75% for the 20- and 50-ppm biofilters, respectively. A partial contributing factor to this drop in mass balance accountability was the production of NO and N2O, which were detected in the biofilter exhaust.

  10. Microbiological and kinetic aspects of a biofilter for the removal of toluene from waste gases

    Energy Technology Data Exchange (ETDEWEB)

    Acuna, M.E.; Perez, F.; Revah, S. [Univ. Autonoma Metropolitana-Iztapalapa, Mexico City (Mexico). Dept. de Ingenieria de Procesos e Hidraulica; Auria, R. [ORSTOM, Mexico City (Mexico). Inst. Francais of Recherche Scientifique pour Developpement en Cooperation

    1999-04-20

    Microbiological and kinetic aspects of a biofilter inoculated with a consortium of five bacteria and two yeast adapted to remove toluene vapors were investigated. Initially the toluene sorption isotherm on peat and the effect of different environmental conditions on the toluene consumption rates of this consortium were measured. The fast start-up of the biofilter and the decay in the elimination capacity (EC) were reproduced using microcosm assays with toluene successive additions. Nutrient limitation and a large degree of heterogeneity were also detected. EC values, extrapolated from microcosms, were higher than biofilter EC when it was operating close to 100% efficiency but tended to relate better as the biofilter EC diminished. In studies on the microbial evolution in the biofilter, an increase in the cell count and variation in the ecology of the consortium were noted. Bacterial counts up to 10 {times} 10{sup 11} cfu/g{sub dry peat} were found in 88 days, which corresponds to about a 10{sup 4} increase from inoculum. Observations with SEM showed a nonuniform biofilm development on the support and the presence of an extracellular material. The results obtained in this work demonstrated that activity measurement in microcosms concomitant to the biofilter operation could be an important tool for understanding, predicting and improving the biofiltration performance.

  11. Oxygen Effects on Thermophilic Microbial Populations in Biofilters Treating Nitric Oxide Containing Off-Gas Streams

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Brady Douglas; Apel, William Arnold; Smith, William Aaron

    2004-04-01

    Electricity generation from coal has increased by an average of 51 billion kWh per year over the past 3 years. For this reason cost-effective strategies to control nitrogen oxides (NOx) from coal-fired power plant combustion gases must be developed. Compost biofilters operated at 55°C at an empty bed contact time (EBCT) of 13 seconds were shown to be feasible for removal of nitric oxide (NO) from synthetic flue gas. Denitrifying microbial populations in these biofilters were shown to reduce influent NO feeds by 90 to 95% at inlet NO concentrations of 500 ppmv. Oxygen was shown to have a significant effect on the NO removal efficiency demonstrated by these biofilters. Two biofilters were set up under identical conditions for the purpose of monitoring NO removal as well as changes in the microbial population in the bed medium under anaerobic and aerobic conditions. Changes in the microbial population were monitored to determine the maximum oxygen tolerance of a denitrifying biofilter as well as methods of optimizing microbial populations capable of denitrification in the presence of low oxygen concentrations. Nitric oxide removal dropped to between 10 and 20% when oxygen was present in the influent stream. The inactive compost used to pack the biofilters may have also caused the decreased NO removal efficiency compared to previous biofiltration experiments. Analysis of the bed medium microbial population using environmental scanning electron microscopy indicated significant increases in biomass populating the surface of the compost when compared to unacclimated compost.

  12. Performance evaluation of the compact aquaculture system integrating submerged fibrousnitrifying biofilters

    Directory of Open Access Journals (Sweden)

    Sorawit Powtongsook

    2012-02-01

    Full Text Available This experiment assessed the performance of submerged fibrous nitrifying biofilters (SFNBs to carry out the zerowaterexchange tilapia cultivation. Without biofilter cleaning, the SFNBs (21 m of biofilter length were susceptible tohydrogen sulfide production when operating beyond the aquaculture density of 13.62 kg/m3. The SFNBs were able tomaintain total ammonia nitrogen (TAN and nitrite below 1.0 mg N/L throughout the experiment and could handle inorganicnitrogen loading as high as 38.6 mg N/L/day when the solid removal from biofilters was performed biweekly. Ammoniumdegradation rate measured at the end of this study was 380±66 mg N/m2/day for biofilters subjected to cleaning. A significantlylower rate of 41.4±2.86 mg N/m2/day was associated with biofilters without any solid removal. Finally, the SFNBsshould be attractive for budget-limited farmers since they are simple to build and operate and can provide alternatives tocage-cultured systems.

  13. Performance of two biofilters with neutral and low pH treating off-gases.

    Science.gov (United States)

    Liu, Jianwei; Liu, Junxin; Li, Lin

    2008-01-01

    Two different functional biofilters were carried out and compared for the treatment of off-gas containing multicomponent odors and volatile organic compounds (VOCs) in this study. The effects of pH values and the empty bed retention time (EBRT) on the performance of the bioreactors were studied; and the characteristics of microbial populations in the two biofilters were also determined. The experimental results indicated that the removal efficiencies of hydrophilic compounds such as butyric acid and ammonia were higher in the neutral pH biofilter (NPB) than those in the low pH biofilter (LPB). In contrast, the removal efficiencies of the compounds with poor water solubility such as styrene and ethyl mercaptan were higher in the LPB than those in the NPB. The characteristics of microbial population in the two biofilters revealed that the heterotrophic bacteria, nonacidophilic thiobacteria, ammonia oxidizing bacteria, and nitrite oxidizing bacteria were major microorganisms in the NPB, whereas acidophilic thiobacteria and fungi were dominant in the LPB. Therefore, the performance of the biofilter depended on the characteristics of the compound being treated and the type of microorganisms.

  14. Performance of two biofilters with neutral and low pH treating off-gases

    Institute of Scientific and Technical Information of China (English)

    LIU Jianwei; LIU Junxin; LI Lin

    2008-01-01

    Two different functional biofilters were carried out and compared for the treatment of off-gas containing multieomponent odors and volatile organic compounds (VOCs) in this study. The effects of pH values and the empty bed retention time (EBRT) on the performance of the bioreactors were studied; and the characteristics of microbial populations in the two biofilters were also determined. The experimental results indicated that the removal etiiciencies of hydrophilic compounds such as butyric acid and ammonia were higher in the neutral pH biofilter (NPB) than those in the low pH biofilter (LPB). In contrast, the removal efficiencies of the compounds with poor water solubility such as styrene and ethyl mercaptan were higher in the LPB than those in the NPB. The characteristics of microbial population in the two biofilters revealed that the heterotrophic bacteria, nonacidophilic thiobacteria, ammonia oxidizing bacteria, and nitrite oxidizing bacteria were major microorganisms in the NPB, whereas acidophilic thiobacteria and fungi were dominant in the LPB. Therefore, the performance of the biofilter depended on the characteristics of the compound being treated and the type of microorganisms.

  15. Ethnografische Diskursanalyse und Sozialwissenschaften

    OpenAIRE

    Macgilchrist, Felicitas; Van Hout, Tom

    2011-01-01

    Ethnografie und Diskursanalyse werden in den Sozialwissenschaften zunehmend kombiniert. In diesem Beitrag wird zunächst ein Überblick gegeben über das entstehende Feld der mit den Epistemologien und Methoden der Ethnografie und Diskursanalyse arbeitenden Forschung. Im zweiten Schritt werden zentral Aspekte eines neuen, computergestützten Ansatzes zur ethnografischen Diskursanalyse vorgestellt. Dieser mikroanalytische Ansatz bietet die Möglichkeit, Erkenntnisse über das Ringen um Deutungsmuste...

  16. Hodenbiopsie, Histologie und TESE

    Directory of Open Access Journals (Sweden)

    Bergmann M

    2007-01-01

    Full Text Available Die Spermatogenese erfolgt in den Keimtubuli, die aus einer Lamina propria und dem Keimepithel bestehen. Das Keimepithel besteht aus Keimzellen und somatischen Sertoli-Zellen. Sertoli-Zellen triggern die Spermatogenese über die hormonellen Stimuli von FSH und Androgenen und bilden die Blut-Hoden-Schranke, die Spermatozyten und Spermatiden vor dem körpereigenen Immunsystem schützt und so eine Autoimmunreaktion verhindert. Die Spermatogenese umfaßt die Proliferation der Spermatogonien, die Meiose der Spermatozyten und die Differenzierung der Spermatiden in Spermatozoen (Spermiogenese. Man unterscheidet I–VI verschiedene Assoziationen von Keimzellen – "Stadien der Spermatogenese" –, die in einem "multi-stage arrangement" in der Längsachse der Keimtubuli angeordnet sind. Verschiedene Spermatogenesedefekte in benachbarten Keimtubuli: "Bunte Atrophie" ist assoziiert mit Differenzierungsdefiziten der Sertoli-Zellen. Biopsien sollten in Bouinscher Lösung fixiert werden. Die Diagnose des Carcinoma in situ erfolgt durch den immunhistochemischen Nachweis der plazentalen alkalischen Phosphatase, die ausschließlich von den CISZellen exprimiert wird. Die histologische Evaluierung erfolgt über ein "score count"-Verfahren und die Applikation moderner histologischer Techniken zum Protein- und mRNA-Nachweis. Der sonographische Befund einer Mikrolithiasis korreliert histologisch mit dem Auftreten intratubulärer sphärischer Konkremente, einer Verdickung der Lamina propria und eines Tubulusschattens. Er ist nicht spezifisch für CIS/TIN, korreliert aber mit CIS/TIN in einem kleinen Subkollektiv von Patienten und bestätigt das erhöhte Risiko infertiler Patienten, einen Hodentumor zu entwickeln. Bei Klinefelter- Patienten besteht die Chance einer fokalen spermatogenetischen Restfunktion, die die Möglichkeit einer TESE/ICSI-Therapie eröffnet. Die Hodenbiopsie sollte nur unter Einhaltung strikter Kriterien für Indikation und histologische Evaluation in

  17. Marktmanipulation und Compliance

    OpenAIRE

    Blumenberg, Axel-Dirk

    2016-01-01

    Die Arbeit behandelt zunächst den Tatbestand der Marktmanipulation aus kriminologischer und wirtschaftlicher Sicht. Im Anschluss wird der damit verbundene Straftatbestand aus der Perspektive des deutschen, spanischen und europäischen Rechts analysiert. Dabei werden auch kriminalpolitische Aspekte, wie die Privatisierung des Strafrechts, die "regulierte Selbstregulierung" und das europäische Gesetzgebungsverfahren berücksichtigt. Im zweiten Teil der Arbeit werden die Möglichkeiten der ...

  18. Demographischer Wandel und Tourismus

    OpenAIRE

    Reuber, Paul; Wolkersdorfer, Günter

    2006-01-01

    In vielen Regionen Deutschlands spielt der Tourismus- und Freizeitmarkt eine bedeutende Rolle. Der Tourismus bietet den Zieldestinationen bezüglich der räumlichen Auswirkungen des demographischen Wandels nicht nur Risiken, sondern durchaus auch erhebliche Chancen. Die wichtigsten Veränderungen des demographischen Wandels für Freizeit und Tourismus betreffen die Gruppe der „Jungen Erwachsenen“ und die Gruppe der „Älteren Menschen“ (50plus-Generation). Beide Gruppen sind durch di...

  19. Geoinformation und Staat

    Science.gov (United States)

    Zypries, Brigitte

    2002-09-01

    Geoinformationen besaßen als Grundlage militärischer Interventionen schon immer einen hohen Stellenwert für den Staat. Im Zeitalter der modernen Informations- und Kommunikationstechnologien wächst in demokratischen Staaten die Bedeutung von Geodaten weit über den Verteidigungsbereich hinaus. Brigitte Zypries, Staatssekretärin im Bundesministerium des Innern (BMI) und Vorsitzende des Interministeriellen Ausschusses für Geoinformationswesen (IMAGI), sprach mit Dipl.-Geogr. Ute C. Bauerüber die Anwendung und Koordinierung von Geodaten in Politik und Staat.

  20. Autonomes Fahren und Stadtstruktur

    OpenAIRE

    2015-01-01

    Mobilität, Verkehr und die physische Gestalt städtischer Räume sind eng miteinander verknüpft [1]. Die Stadtstruktur bildet eine wichtige Grundlage für Mobilitätsentscheidungen von Haushalten und Unternehmen und gibt in entscheidendem Maße vor, welche Formen von Verkehr ermöglicht oder aber auch ausgeschlossen werden. Kompakte Stadtstrukturen mit hoher Dichte und Nutzungsmischung bieten gute Voraussetzungen für kurze Wege, ein leistungsfähiges öffentliches Verkehrsangebot, fördern den Fuß- un...

  1. Virtuelle und ideale Welten

    OpenAIRE

    Bertrand, Cyrille-Paul; Cremers, Martin; Erben, Dietrich; Gehmann, Ulrich; Gerbing, Chris; Gleitsmann, Rolf-Jürgen; Guggenberger, Bernd; Holmer, Sebastian; Krämer, Steffen; Kunze, Rolf-Ulrich; Oetzel, Günther; Schmidt, Michael; Schulze, Ulrich

    2017-01-01

    Technik und technischer Wandel zählen zu jenen Faktoren, die unser (all-)tägliches Leben entscheidend prägen. Dieser Sachverhalt dürfte in unserem technischen Zeitalter kaum einer besonderen Begründung bedürfen. Es liegt auf der Hand, dass die Menschheit von Technik und technischem Fortschritt abhängig geworden ist, und dies nicht erst in unserer Zeit. Seit jeher war es der Technik entwickelnde und zielgerichtet einsetzende Mensch, der vermittels ,seiner‘ Technik Lebensräume gestaltete, verä...

  2. Digital Natives und Datenschutz

    Directory of Open Access Journals (Sweden)

    Triz Heider

    2010-04-01

    Full Text Available Dieser Artikel lädt dazu ein, sich ein Bild der virtuellen Welt zu machen, ihre eingeborenen User zu verstehen, ihre Sprache und Kultur kennen zu lernen und damit einen Schritt zur Integration in „die digitale Gesellschaft“ (falls es sie gibt zu tun. Es findet eine Auseinandersetzung über die aktuelle Entwicklung des Internets, notwendige Kompetenzen Hilfesuchender und die Architektur von virtueller Beratung statt. Aspekte von Datenschutz und Privatsphäre runden die Ausführungen ab. Dabei werden sowohl aktuelle Themen angesprochen, als auch Vergleiche mit anderen, großen Internetangeboten wie SocialNetworks herangezogen.

  3. The use of white-rot fungi as active biofilters

    Energy Technology Data Exchange (ETDEWEB)

    Braun-Luellemann, A.; Johannes, C.; Majcherczyk, A.; Huettermann, A. [Univ. Goettingen (Germany). Forstbotanisches Inst.

    1995-12-31

    White-rot fungi, growing on lignocellulosic substrates, have been successfully used as active organisms in biofilters. Filters using these fungi have a very high biological active surface area, allowing for high degrees of retention, a comparatively low pressure drop, and a high physical stability. The unspecific action of the extracellular enzymes of the white-rot fungi allows for the degradation of a wide variety of substances by the same organism. Degradation of several compounds in the gas phase by the white-rot fungi Trametes versicolor, Pleurotus ostreatus, Bjerkandera adusta, and Phanerochaete chrysosporium was tested. Among the aromatic solvents, styrene was the compound that was most readily degraded, followed by ethylbenzene, xylenes, and toluene. Tetrahydrofuran and dichloromethane were also degraded, whereas dioxane could not be attacked by fungi under the conditions used. Acrylonitrile and aniline were degraded very well, whereas pyridine was resistant to degradation. The process for removing styrene is now in the scaling-up stage.

  4. N2O emissions from full-scale nitrifying biofilters.

    Science.gov (United States)

    Bollon, Julien; Filali, Ahlem; Fayolle, Yannick; Guerin, Sabrina; Rocher, Vincent; Gillot, Sylvie

    2016-10-01

    A full-scale nitrifying biofilter was continuously monitored during two measurement periods (September 2014; February 2015) during which both gaseous and liquid N2O fluxes were monitored on-line. The results showed diurnal and seasonal variations of N2O emissions. A statistical model was run to determine the main operational parameters governing N2O emissions. Modification of the distribution between the gas phase and the liquid phase was observed related to the effects of temperature and aeration flow on the volumetric mass transfer coefficient (kLa). With similar nitrification performance values, the N2O emission factor was twice as high during the winter campaign. The increase in N2O emissions in winter was correlated to higher effluent nitrite concentrations and suspected increased biofilm thickness.

  5. Mineralogical and chemical-physical effects of hydrocarbon permeation in composite liners and cut-off walls. Final report; Mineralogische und chemisch-physikalische Auswirkungen der Permeation von Kohlenwasserstoffen in Kombinationsdichtungen und -dichtwaenden. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kalbe, U.; Berger, W.; Mueller, W.; Brune, M.; Eckardt, J.; Tatzky-Gerth, R.; Ache, W.; Goebbels, J. [Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin (Germany); Breu, J.; Kerzdoerfer, H. [Regensburg Univ. (Germany). Inst. fuer Anorganische Chemie

    2000-05-31

    die Auswirkungen der Schadstoffpermeation auf die Abdichtungsmaterialien untersucht. Schwerpunkte der hier vorgestellten Arbeiten waren Untersuchungen: - zur Auswirkung der Permeation des Gemsiches an organischen Verbindungen auf die Eigenschaften der Kunststoffdichtungsbahn, - zur vertikalen Verteilung der organischen Verbindungen in den mineralischen Dichtungen, - zu Veraenderungen der mineralogischer, mikromorphologischer und bodenmechanischer Eigenschaften der mineralischen Dichtungsmaterialien, - zu mikrobiellen Aktivitaeten in den mineralischen Dichtungen. Daneben wurden Stofftransportparameter bestimmt und eine Modellierung des Stofftransportes durchgefuehrt. Die verschiedenen untersuchten Materialien der Kombinationsdichtungen erwiesen sich unter den extremen Bedingungen als ein stabiles und effizientes Abdichtungssystem. (orig.)

  6. Epilepsie und psychiatrische Erkrankungen

    Directory of Open Access Journals (Sweden)

    Baumgartner C

    2008-01-01

    Full Text Available Psychiatrische Erkrankungen treten bei Epilepsiepatienten signifikant häufiger auf als in der Allgemeinbevölkerung und als bei Patienten mit anderen chronischen Erkrankungen. Die Depression stellt die häufigste psychiatrische Begleiterkrankung bei Epilepsie dar. Die Häufigkeit von Depressionen korreliert mit der Anfallskontrolle: Sie liegt zwischen 3 und 9 % bei gut kontrollierter Epilepsie, jedoch zwischen 20 und 55 % bei Patienten mit therapieresistenten Epilepsien. Umgekehrt ist bei Patienten mit neu diagnostizierten Epilepsien anamnestisch signifikant häufiger eine Depression zu erheben als in einem Vergleichskollektiv. Diese bidirektionale Beziehung zwischen Epilepsie und Depression könnte durch gemeinsame Pathomechanismen beider Erkrankungen erklärt werden. Obwohl das Vorliegen und der Schweregrad einer Depression die wichtigsten Prädiktoren für die Lebensqualität bei Epilepsiepatienten darstellen, werden Depressionen bei Epilepsiepatienten unterdiagnostiziert und unterbehandelt. Eine psychopharmakologische Behandlung sollte bei Vorliegen einer Begleitdepression deshalb unverzüglich initiiert werden, das epileptogene Potential von Antidepressiva stellt dabei ein vernachlässigbares Risiko dar. Die Prävalenz psychotischer Störungen bei Epilepsiepatienten liegt zwischen 2 und 8 %, wobei sogenannte episodische Psychosen (iktale, postiktale und Alternativpsychosen, die in einem zeitlichen Bezug zum Anfallsgeschehen stehen, und chronische Psychosen (interiktale Psychosen ohne zeitlichen Bezug zu den Anfällen, unterschieden werden können. Die Prävalenz von Angststörungen bei Epilepsiepatienten liegt zwischen 15 und 25 %. Man kann zwischen präiktaler, iktaler, postiktaler und interiktaler Angst unterscheiden.

  7. Wissensmanagement und Medienbildung - neue Spannungsverhältnisse und Herausforderungen

    Directory of Open Access Journals (Sweden)

    Gabi Reinmann

    2005-05-01

    Full Text Available Begrifflichkeiten schaffen Bewusstsein, haben Wirkungen auf Denken und Handeln und können Zielsetzungen von morgen beeinflussen. Der vorliegende Beitrag möchte der Frage nachgehen, welche Funktion der Begriff des Wissensmanagements in pädagogischen Kontexten hat und künftig haben wird, welche Chancen und Risiken davon ausgehen und in welchem Verhältnis er zum Begriff der Medienbildung steht oder stehen könnte.

  8. Armut und Gesundheit

    OpenAIRE

    Lampert, Thomas; Kroll, Lars Eric

    2010-01-01

    Menschen in Armut haben einen schlechteren allgemeinen Gesundheitszustand, zeigen häufiger gesundheitsriskanteres Verhalten und haben ein erhöhtes Risiko für bestimmte Erkrankungen. Weitere Zusammenhänge von Armut und Gesundheit, dargestellt mit Ergebnissen der Studie "Gesundheit in Deutschland aktuell" (GEDA), können Sie der aktuellen Ausgabe von GBE kompakt entnehmen.

  9. Gesundheit, Essen und Nachhaltigkeit

    DEFF Research Database (Denmark)

    Reisch, Lucia

    2012-01-01

    zwischen Gesundheit, Essen und Nachhaltigkeit geht der Auftrag der Ernährungsaufklärung heute thematisch über den der klassischen Aufklärung hinaus. Vor diesem Hintergrund beschäftigt sich der Beitrag mit den Fragen, wie heute eine „gesunde, nachhaltige Ernährung“ - und damit das Ziel einer gelingenden...

  10. Steuern und Governance

    Directory of Open Access Journals (Sweden)

    Eduard Müller

    2014-05-01

    Full Text Available ENGLISH: Taxation, in the modern state, has long been a mass phenomenon with an interdisciplinary outlook. On the macro level of the state, a new generation of administrative reforms has crystallized under the label “good public governance”. These reforms seek to resolve regulatory interdependence of state and non - state actors by way of cooperation and interaction. In parallel, on the micro level of businesses, “corporate governance” – voluntary compliance with legal and ethical standards – has become an increasingly important issue. With a view to tax law and tax collection, these developments open up new possibilities to raise tax compliance by means of consensual and cooperative instruments and, accordingly, address taxation as a mass phenomenon. DEUTSCH: Besteuerung ist im modernen Staat ein Massenphänomen und längst interdisziplinär ausgerichtet. Auf der Makro-Ebene des Staates hat sich unter dem Begriff Good Public Governance eine neue Generation von Staats- und Verwaltungsreformen herausgebildet, die Regelungsbeziehungen von staatlichen und nichtstaatlichen Akteuren durch Kooperationen und Interaktionen zu lösen versucht. Parallel dazu hat auf der Mikro-Ebene der Unternehmen mit dem Thema Corporate Governance die freiwillige Einhaltung von rechtlichen und ethischen Regeln an Bedeutung gewonnen. Für das Steuerrecht und den Steuervollzug resultieren aus diesen Entwicklungen neue Möglichkeiten, durch Nutzung konsens- und kooperationsorientierter Instrumente die Tax Compliance zu erhöhen und so dem Massenphänomen Besteuerung gerecht zu werden.

  11. Neugier und epistemisches Handeln

    OpenAIRE

    2008-01-01

    Spezifische epistemische Neugier ist ein motivationaler Zustand, der durch konkrete Fragen ausgelöst und durch Wissenserwerb befriedigt wird. In der vorliegenden Arbeit geht es um die Entstehungsbedingungen spezifischer epistemischer Neugier und die Charakteristika neugiermotivierten Handelns. In kritischer Auseinandersetzung mit vorhandenen Neugiertheorien wird ein integratives Modell entwickelt, dem zufolge Neugier auf der metakognitiven Erfahrung einer gesteigerten kognitiven Aktivität ber...

  12. Aquarium nitrification revisited: Thaumarchaeota are the dominant ammonia oxidizers in freshwater aquarium biofilters.

    Directory of Open Access Journals (Sweden)

    Laura A Sauder

    Full Text Available Ammonia-oxidizing archaea (AOA outnumber ammonia-oxidizing bacteria (AOB in many terrestrial and aquatic environments. Although nitrification is the primary function of aquarium biofilters, very few studies have investigated the microorganisms responsible for this process in aquaria. This study used quantitative real-time PCR (qPCR to quantify the ammonia monooxygenase (amoA and 16S rRNA genes of Bacteria and Thaumarchaeota in freshwater aquarium biofilters, in addition to assessing the diversity of AOA amoA genes by denaturing gradient gel electrophoresis (DGGE and clone libraries. AOA were numerically dominant in 23 of 27 freshwater biofilters, and in 12 of these biofilters AOA contributed all detectable amoA genes. Eight saltwater aquaria and two commercial aquarium nitrifier supplements were included for comparison. Both thaumarchaeal and bacterial amoA genes were detected in all saltwater samples, with AOA genes outnumbering AOB genes in five of eight biofilters. Bacterial amoA genes were abundant in both supplements, but thaumarchaeal amoA and 16S rRNA genes could not be detected. For freshwater aquaria, the proportion of amoA genes from AOA relative to AOB was inversely correlated with ammonium concentration. DGGE of AOA amoA genes revealed variable diversity across samples, with nonmetric multidimensional scaling (NMDS indicating separation of freshwater and saltwater fingerprints. Composite clone libraries of AOA amoA genes revealed distinct freshwater and saltwater clusters, as well as mixed clusters containing both freshwater and saltwater amoA gene sequences. These results reveal insight into commonplace residential biofilters and suggest that aquarium biofilters may represent valuable biofilm microcosms for future studies of AOA ecology.

  13. Biofilters to treat the pesticides wastes from spraying applications: results after 4 years of study.

    Science.gov (United States)

    Pigeon, O; De Vleeschouwer, C; Cors, F; Weickmans, B; Huyghebaert, B; Planchon, V; Pussemier, L; Culot, M

    2006-01-01

    Biofilters were developed in order to eliminate or reduce the quantity of pesticides from rinsing and cleaning waters of sprayers. Biofilters consist in 1, 2 or 3 plastic containers of 1 m3 placed in a vertical pile and containing a substrate elaborated from a homogenised mixture of local soil, chopped straw and compost able to absorb and degrade the pesticides. Biofilters are installed near the area for cleaning and rinsing the sprayer and the waste waters are pumped into the system. Since 2002, a pilot study is carried out in Belgium in order to evaluate the efficacy of these systems. Twenty pilot systems were installed since 2002 until 2004 in several farms, agricultural technical centres or schools and in a municipal maintenance service. The efficacy of the biofilters was studied for several chemical classes of herbicides (sulfonylurea, aryloxyalcanoic acids, chloroacetanilides), insecticides (pyrethroids, carbamates) and fungicides (dicarboximides, phenylamides, triazoles and strobilurines). The balance of the inputs and the outputs of the pesticides was determined by monitoring the elutes. The degradation kinetic of pesticides into the substrate was evaluated by analysing the pesticides into the substrate. The microbiological activity of the substrate was also evaluated by measuring respiration and some indirect parameters like dry matter content, Kjeldahl nitrogen content, organic carbon content and biological oxygen demand (BOD). Results obtained until now after four years of experiments have showed an overall good efficacy (retention) of pesticides by the biofilter and a high degradation rate for the majority of pesticides. Biofilters permit to reduce highly the quantity of pesticides from rinsing and cleaning waters of sprayers and contribute significantly to the reduction of the contamination of surface water. Biofilters are now registered by the Ministry of Agriculture and Environment of the Walloon Region in Belgium and are recommended to pesticides

  14. Aquarium nitrification revisited: Thaumarchaeota are the dominant ammonia oxidizers in freshwater aquarium biofilters.

    Science.gov (United States)

    Sauder, Laura A; Engel, Katja; Stearns, Jennifer C; Masella, Andre P; Pawliszyn, Richard; Neufeld, Josh D

    2011-01-01

    Ammonia-oxidizing archaea (AOA) outnumber ammonia-oxidizing bacteria (AOB) in many terrestrial and aquatic environments. Although nitrification is the primary function of aquarium biofilters, very few studies have investigated the microorganisms responsible for this process in aquaria. This study used quantitative real-time PCR (qPCR) to quantify the ammonia monooxygenase (amoA) and 16S rRNA genes of Bacteria and Thaumarchaeota in freshwater aquarium biofilters, in addition to assessing the diversity of AOA amoA genes by denaturing gradient gel electrophoresis (DGGE) and clone libraries. AOA were numerically dominant in 23 of 27 freshwater biofilters, and in 12 of these biofilters AOA contributed all detectable amoA genes. Eight saltwater aquaria and two commercial aquarium nitrifier supplements were included for comparison. Both thaumarchaeal and bacterial amoA genes were detected in all saltwater samples, with AOA genes outnumbering AOB genes in five of eight biofilters. Bacterial amoA genes were abundant in both supplements, but thaumarchaeal amoA and 16S rRNA genes could not be detected. For freshwater aquaria, the proportion of amoA genes from AOA relative to AOB was inversely correlated with ammonium concentration. DGGE of AOA amoA genes revealed variable diversity across samples, with nonmetric multidimensional scaling (NMDS) indicating separation of freshwater and saltwater fingerprints. Composite clone libraries of AOA amoA genes revealed distinct freshwater and saltwater clusters, as well as mixed clusters containing both freshwater and saltwater amoA gene sequences. These results reveal insight into commonplace residential biofilters and suggest that aquarium biofilters may represent valuable biofilm microcosms for future studies of AOA ecology.

  15. Thermodynamik grundlagen und technische anwendungen

    CERN Document Server

    Baehr, Hans Dieter

    2009-01-01

    Für die aktualisierte 14. Auflage des bewährten Lehrbuchs der Technischen Thermodynamik wurde das Kapitel über Wärmekraftanlagen gründlich bearbeitet und durch einen Abschnitt zur Energiewandlung ergänzt: Die Energiebedarfsstruktur von Deutschland wird erläutert, und die möglichen Energiewandlungspfade werden diskutiert. Schwerpunkt des Buches ist die ausführliche und auch dem Anfänger verständliche Darstellung der Grundlagen der Thermodynamik mit der sorgfältigen Einführung der thermodynamischen Begriffe und den fundamentalen Bilanzgleichungen für Energie, Entropie und Exergie. Die thermodynamischen Eigenschaften reiner Fluide und fluider Gemische werden eingehend erläutert. Darauf aufbauend wird die Thermodynamik der Gemische und der chemischen Reaktionen entwickelt. Auch die thermodynamischen Aspekte wichtiger energie- und verfahrenstechnischer Anwendungen werden praxisnah behandelt: - Strömungs- und Arbeitsprozesse, - thermische Stofftrennverfahren, - Verbrennungsprozesse und Verbrennungsk...

  16. Antepartuales fetales Elektrokardiogramm und Kardiotokographie

    OpenAIRE

    2006-01-01

    Es wurden 65 Patientinnen zwischen der 17. und 41. Schwangerschaftswoche unter Berücksichtigung der Hauptpathologien "intauterine Wachstumsretardierung" und "Gestationsdiabetes" simultan mit Hilfe der Kineto-Kardiotokographie (KCTG) und des fetalen abdominalen EKGs (AECG) untersucht. Neben dem direkten Vergleich von KCTG- und AECG-Messung wurde die Registrierqualität des AECG hinsichtlich verschiedener Einflussgrößen untersucht und eine Analyse der errechneten Durchschnitts-EKGs vorgenommen. ...

  17. Die amtliche Kinder- und Jugendhilfestatistik

    OpenAIRE

    Schilling, Matthias

    2003-01-01

    Unter Rückgriff auf verschiedene wissenschaftliche Methoden umfasst die Dissertation eine differenzierte Untersuchung der amtlichen Kinder- und Jugendhilfestatistik (KJH-Statistik). Da die wissenschaftliche Sozialpädagogik erst langsam und zögerlich beginnt, die amtliche Statistik der Kinder- und Jugendhilfe wahrzunehmen, liegt das Forschungsinteresse darin, dass eine grundlegende und umfassende wissenschaftliche Analyse der Möglichkeiten und Grenzen der KJH-Statistik vorgenommen wird. Die KJ...

  18. PLFA profiles of drinking water biofilters with different acetate and glucose loadings.

    Science.gov (United States)

    Yu, Xin; Shi, Xu; Wei, Bo; Ye, Lin; Zhang, Shuting

    2009-08-01

    The biofilters fed with acetate or glucose and their phospholipid fatty acid (PLFA) profiles were investigated to observe the impact of organic matter concentrations on the microbial community structure in the drinking water production system. PLFA markers for bacteria were predominant in all of the biofilters and made up over half of the total PLFA content. PLFA diversity was compared and the biofilters fed with glucose had higher diversity. The Shannon-Wiener (or sometimes known as just Shannon diversity index) indices in the biofilters fed with acetate were from 0.68 to 0.97, while the indices in the biofilters fed with glucose were from 0.95 to 1.25. Principle components analysis showed that carbon sources and media depth were responsible for 68 and 17% of the total PLFA variance, respectively. The results indicated that PLFA analysis could be useful in illustrating microbial community structure in drinking water bioreactors, and microbial community structure was impacted by carbon substrates.

  19. Evaluating Escherichia coli removal performance in stormwater biofilters: a preliminary modelling approach.

    Science.gov (United States)

    Chandrasena, G I; Deletic, A; McCarthy, D T

    2013-01-01

    Stormwater biofilters are not currently optimised for pathogen removal since the behaviour of these pollutants within the stormwater biofilters is poorly understood. Modelling is a common way of optimising these systems, which also provides a better understanding of the major processes that govern the pathogen removal. This paper provides an overview of a laboratory-scale study that investigated how different design and operational conditions impact pathogen removal in the stormwater biofilters. These data were then used to develop a modelling tool that can be used to optimise the design and operation of the stormwater biofilters. The model uses continuous simulations where adsorption and desorption were dominant during wet weather periods and first order die-off kinetics were significant in dry periods between the wet weather events. Relatively high Nash Sutcliffe Efficiencies (>0.5) indicate that the calibrated model is in good agreement with observed data and the optimised model parameters were comparable with values reported in the literature. The model's sensitivity is highest towards the adsorption process parameter followed by the die-off and desorption rate parameters, which implies that adsorption is the governing process of the model. Vegetation is found to have an impact on the wet weather processes since the adsorption and desorption parameters vary significantly with the different plant configurations. The model is yet to be tested against field data and needs to be improved to represent the effect of some other biofilter design configurations, such as the inclusion of the submerged zone.

  20. [Metabolic properties of the microbial community in the biofilters using biolog microplates].

    Science.gov (United States)

    Xi, Jin-Ying; Hu, Hong-Ying; Jiang, Jian; Qian, Yi

    2005-07-01

    It is very important to know the structure and metabolic function of the microbial community in a bioreactor in order to improve its performance. In this study, two biofilters, packed with wood chips and granular activated carbons respectively, were operated for 160 days to treat toluene gas. The metabolic profiles of the microbial communities in the biofilters were monitored using Biolog microplates periodically during the experiments. The metabolic activities of the microorganisms in both biofilters were observed to decrease during long-term operation. According to the results of principle components analysis, the metabolic profiles of the microbial communities did not change much in the former period of the operation, but they changed in the inlet layers on day 103 and changed throughout the filter beds on day 160. The variation of the metabolic profiles in both biofilters showed little difference, which suggested that the packing media had little effect on them during long-term operation. Among the 95 carbon sources in Biolog microplate, carboxylic acids and amino acids were much easier to be utilized by the microorganisms in the biofilters than the other carbon

  1. Investigation of efficiency of air cleaning from acetone using a segmental construction biofilter

    Directory of Open Access Journals (Sweden)

    Denas Bacevičius

    2015-10-01

    Full Text Available Volatile organic compounds, e. g. acetone, have a direct impact on climate change, decrease of ozone in the air, and on the growth of greenhouse effect. One of the most popular air purifying methods from VOC is a biological air cleaning. Experimental investigations were conducted to determine the efficiency of the new structure of biofilter with polypropylene plates segments. During the investigations the efficiency of segmental construction biofilter of air purification at different initial concentrations of pollutants was determined. Different concentrations of pollutants were estimated during the acetone dilution with water. During the tests the efficiency of biofilter air purification from acetone vapor and its change under different concentrations of vapors was set. Based on test results, the maximum efficiency of biofilter air purification was up to 93%. Studies have shown that increasing the allowable pollutant concentration, the efficiency of air purification unit decreases. Increasing the concentration of supplied acetone vapor into the biofilter from 232 to 701 mg/m3, cleaning efficiency decreased from 92.8 to 82.3%. Since microorganisms fail to oxidize organic compounds, the filter works better at lower initial concentrations of pollutants.

  2. Relationships between biomass, pressure drop, and performance in a polyurethane biofilter.

    Science.gov (United States)

    Ryu, Hee Wook; Cho, Kyung-Suk; Chung, Dong Jin

    2010-03-01

    In biofilters for controlling volatile organic compounds (VOCs), clogging in the filter bed due to overgrowth of biomass causes the deterioration of biofilter performance. In this study, the relationships between biofilter performance, biomass concentration (X), and pressure drop (DeltaP) was qualitatively and quantitatively evaluated in a polyurethane (PU) biofilter. Benzene was used as a model VOC. The relationship between DeltaP and X at a moisture content of 80-90% was expressed as log DeltaP (mm H(2)Om(-1))=0.315+3.87 log X (g-dry cell weight (DCW) g-PU(-1)), 0.8biofilter performance for long-term operation.

  3. Efficient Total Nitrogen Removal in an Ammonia Gas Biofilter through High-Rate OLAND

    DEFF Research Database (Denmark)

    De Clippeleir, Haydée; Courtens, Emilie; Mosquera, Mariela;

    2012-01-01

    Ammonia gas is conventionally treated in nitrifying biofilters; however, addition of organic carbon to perform post-denitrification is required to obtain total nitrogen removal. Oxygen-limited autotrophic nitrification/denitrification (OLAND), applied in full-scale for wastewater treatment, can.......86 ± 0.04 kg N m–3 biofilter d–1 and an empty bed residence time of 14 s. After 45 days of operation a stable nitrogen removal rate of 0.67 ± 0.06 kg N m–3 biofilter d–1, an ammonia removal efficiency of 99%, a removal of 75–80% of the total nitrogen, and negligible NO/N2O productions were obtained...... at water flow rates of 1.3 ± 0.4 m3 m–2 biofilter section d–1. Profile measurements revealed that 91% of the total nitrogen activity was taking place in the top 36% of the filter. This study demonstrated for the first time highly effective and sustainable autotrophic ammonia removal in a gas biofilter...

  4. Introductory study to mathematics modelling of fluid flow in the screw compressors; Einfuehrungsstudie zur mathematischen Modellierung der Stroemungen in Schraubenkompressoren

    Energy Technology Data Exchange (ETDEWEB)

    Svigler, J.; Vimmr, J. [Westboehmische Univ. Pilsen (Czechoslovakia). Lehrstuhl fuer Mechanik

    2000-07-01

    A fast development of the screw machines leads to the investigation of the physical processes, which take place in the work space of the screw machine and in the gaps on its boundary. These processes have a great influence on the performance of the screw machine especially with regard to its efficiency, therefore its knowledge is very important. It is necessary to turn our attention to the fluid dynamics of the screw machines. This paper deals with the preliminary analysis of the fluid flow in the screw machines. In this paper numerical computation of the compressible inviscid fluid flow in the work space of the screw machines and through the sealing gaps which are situated between the stator and the head of the female rotor tooth, is presented. The mathematical model of two- and three-dimensional inviscid compressible flow is described by the conservative system of the Euler equations. This problem was solved by the cell-centred finite volume method on a structured quadrilateral mesh. (orig.) [German] Die schnelle Entwicklung der Schraubenmaschinen fuehrt zur Notwendigkeit einer Untersuchung der physikalischen Vorgaenge, die im Arbeitsraum und in den arbeitsraumbegrenzenden Spalten der Schraubenmaschine ablaufen. Diese Vorgaenge beeinflussen nachhaltig das Betriebsverhalten sowie die Energiewandlungsguete, womit deren Kenntnis und der Information ueber die Details eine ausserordentliche Bedeutung zukommt. Einen Ausgangspunkt fuer die Analyse stellen die Kenntnisse im Bereich der kompressiblen Fluide dar. Der Zustand kann vor allem durch das Geschwindigkeits-, Druck-, und Temperaturfeld beurteilt werden. Der Beitrag beschaeftigt sich mit der Problematik der Stroemungsuntersuchungen des Gases im Arbeitsraum der Schaubenmaschine und im Gehaeusespalt. Die Aufgabe wird dreidimensional behandelt und auf eine Art und Weise formuliert, dass sie die Voraussetzung fuer die Erstellung eines raeumlichen Modells und der damit gekoppelten mathematischen Loesung schafft. Die

  5. Molecular characterization of microbial populations in full-scale biofilters treating iron, manganese and ammonia containing groundwater in Harbin, China.

    Science.gov (United States)

    Li, Xiang-kun; Chu, Zhao-rui; Liu, Ya-jun; Zhu, Meng-ting; Yang, Liu; Zhang, Jie

    2013-11-01

    In iron and manganese-containing groundwater treatment for drinking water production, biological filter is an effective process to remove such pollutants. Until now the exact microbial mechanism of iron and manganese removal, especially coupled with other pollutants, such as ammonia, has not been clearly understood. To assess this issue, the performance of a full-scale biofilter located in Harbin, China was monitored over four months. Microbial populations in the biofilter were investigated using T-RFLP and clone library technique. Results suggested that Gallionella, Leptothrix, Nitrospira, Hyphomicrobium and Pseudomonas are dominant in the biofilter and play major roles in the removal of iron, manganese and ammonia. The spatial distribution of microbial populations along the depth of the biofilter demonstrated the stratification of the removal of iron, manganese and ammonia. Additionally, the absence of ammonia-oxidizing bacteria in the biofilter implicated that ammonia-oxidizing archaea might be responsible for the oxidation of ammonia to nitrite.

  6. Multiple Sklerose und Schwangerschaft

    Directory of Open Access Journals (Sweden)

    Berger T

    2009-01-01

    Full Text Available Da Multiple Sklerose (MS eine der häufigsten neurologischen Erkrankungen im jungen Erwachsenenalter ist und Frauen zwei- bis dreimal häufiger als Männer betrifft, sind Fragen nach Fertilität, Schwangerschaft und Geburt ein bedeutsames Gesprächsthema zwischen Patientinnen und behandelndem Arzt. Eine Schwangerschaft geht einher mit multiplen physiologischen Veränderungen, die auch zu einer Änderung des Immunstatus führen und so den Verlauf der MS (günstig beeinflussen können. Für die Dauer der Schwangerschaft ist eine Stabilisierung der MS mit einer Abnahme der Schubfrequenz festzustellen. Obwohl es dann in den ersten 6 Monaten postpartal zu einer Zunahme der Krankheitsaktivität kommen kann, lässt sich grundsätzlich sagen, dass eine Schwangerschaft keine längerfristigen negativen Effekte auf den weiteren Krankheitsverlauf ausübt. Auch hat MS keinen nachteiligen Einfluss auf die fetale Entwicklung und den positiven Geburtsausgang. Prinzipiell sind alle immunmodulatorischen und immunsuppressiven Medikamente in der Schwangerschaft kontraindiziert und sollten daher bei geplanter oder eingetretener Schwangerschaft unverzüglich abgesetzt werden. Eine Schubtherapie mit Kortikosteroiden kann hingegen durchaus auch während einer bestehenden Schwangerschaft durchgeführt werden.

  7. Mediendidaktik und Wissensmanagement

    Directory of Open Access Journals (Sweden)

    Gabi Reinmann-Rothmeier

    2002-10-01

    Full Text Available Mediendidaktik und Wissensmanagement – das ist auf den ersten Blick ein ungleiches Paar: Die Mediendidaktik ist eine Teildisziplin der (Medien- Pädagogik, während Wissensmanagement ein genuin wirtschaftliches Thema mit betriebswirtschaftlichen Akzenten ist. Annäherungen zwischen der Mediendidaktik und Wissensmanagement gibt es zum einen durch den sog. E-Learning-Trend seitens der Wirtschaft, der mediendidaktisches Wissen und Können auf den Plan ruft, zum anderen durch wachsendes Interesse am Thema Wissensmanagement seitens der Pädagogik. Der Beitrag beschreibt sowohl für das E-Learning als auch für das Wissensmanagement aus pädagogisch-psychologischer Sicht jeweils ein Orientierungsmodell; beide Modelle machen die Berührungspunkte zwischen Mediendidaktik und Wissensmanagement deutlich. Neben einem Überblick über wirtschaftliche Argumente für eine Verschmelzung von E-Learning und Wissensmanagement werden aufbauend auf den beiden Orientierungsmodellen theoretische und praktische Verbindungslinien zwischen E-Learning und Wissensmanagement sowie die Rolle der Mediendidaktik in dem daraus entstehenden Wechselverhältnis herausgearbeitet.

  8. Teilchendetektoren Grundlagen und Anwendungen

    CERN Document Server

    Kolanoski, Hermann

    2016-01-01

    In diesem Buch werden die experimentellen Grundlagen von Teilchendetektoren und ihre Anwendung in Experimenten beschrieben. Die Entwicklung von Detektoren ist ein wichtiger Bestandteil der Teilchen-, Astroteilchen- und Kernphysik und gehört daher zum Handwerk des Experimentalphysikers in diesen Gebieten. Dieses umfassende Werk beinhaltet den kompletten Stoff für entsprechende Master-Module in der experimentellen Teilchenphysik, geht aber im Inhalt auch darüber hinaus. Zielgruppe sind Studierende, die sich in die Materie vertiefen möchten, aber auch Lehrende und Wissenschaftler, die das Buch zum Einstieg in das wissenschaftliche Arbeiten an Detektorentwicklungen verwenden können. Zielrichtung des Buches ist, die physikalischen Grundlagen für die Detektoren und ihrer verschiedenen Ausführungen so klar wie möglich und so tiefgehend wie nötig darzustellen. Die Breite des für die Detektorentwicklung nötigen Wissens umfasst viele Bereiche der Physik und Technik, von den Wechselwirkun...

  9. Kinder- und Jugendliteratur – ein literarisches Schattendasein

    Directory of Open Access Journals (Sweden)

    Gisela Bürki

    2002-07-01

    Full Text Available Das zweibändige Taschenbuch der Kinder- und Jugendliteratur behandelt in 43 von verschiedenen Autorinnen und Autoren verfassten Beiträgen sowohl Begriffsbestimmung und Geschichte der deutschsprachigen Kinder- und Jugendliteratur als auch gattungstheoretische Fragen, Thematisches ausgewählte thematische Aspekte und verwandte Medien. Das Handbuch dürfte sich als ein Basiswerk der Kinder- und Jugendliteraturforschung herausstellen.

  10. Studies on bio-oxidation of coal mine gas by a biofilter

    Institute of Scientific and Technical Information of China (English)

    YU Hai-xia; MIN Hang; L(U) Zhen-mei

    2010-01-01

    A new biofilter technology was used to control the methane concentration in the coal mine. The results indicate that the biofilter achieves a steady methane removal capacity of 1 470mg/(L·h)after 30 days start-up. More than 90% of the methane can be removed with an empty bed retention time (EBRT) of 5.6 min when the inlet concentration of methane (IMC) is lower than 70 mg/L (10%, V/V) and about 80% when IMC is at 105 mg/L(15%, V/V). The biofilter is still a reliable method to control methane concentration as an auxiliary means to boost coal mine production safety together with aggrandized ventilation and drainage technologies, even though the removal efficiency of methane is not very satisfactory with a high IMC (>10%) or a short EBRT (<3.8 min).

  11. Bacterial dynamics in steady-state biofilters: beyond functional stability.

    Science.gov (United States)

    Cabrol, Léa; Malhautier, Luc; Poly, Franck; Lepeuple, Anne-Sophie; Fanlo, Jean-Louis

    2012-01-01

    The spatial and temporal dynamics of microbial community structure and function were surveyed in duplicated woodchip-biofilters operated under constant conditions for 231 days. The contaminated gaseous stream for treatment was representative of composting emissions, included ammonia, dimethyl disulfide and a mixture of five oxygenated volatile organic compounds. The community structure and diversity were investigated by denaturing gradient gel electrophoresis on 16S rRNA gene fragments. During the first 42 days, microbial acclimatization revealed the influence of operating conditions and contaminant loading on the biofiltration community structure and diversity, as well as the limited impact of inoculum compared to the greater persistence of the endogenous woodchip community. During long-term operation, a high and stable removal efficiency was maintained despite a highly dynamic microbial community, suggesting the probable functional redundancy of the community. Most of the contaminant removal occurred in the first compartment, near the gas inlet, where the microbial diversity was the highest. The stratification of the microbial structures along the filter bed was statistically correlated to the longitudinal distribution of environmental conditions (selective pressure imposed by contaminant concentrations) and function (contaminant elimination capacity), highlighting the central role of the bacterial community. The reproducibility of microbial succession in replicates suggests that the community changes were presumably driven by a deterministic process.

  12. Removal of alpha-pinene from gases using biofilters containing fungi

    Science.gov (United States)

    van Groenestijn, J. W.; Liu, J. X.

    Biofiltration is cost-effective for the treatment of gases containing low concentrations of volatile organic compounds (biofilters, based on compost and bacterial activity, face problems with the elimination of hydrophobic compounds. Besides that, biofilter operational stability is often hampered by acidification and drying out of the filter bed. To overcome these problems, biofilters with fungi on inert packing material have been developed. Fungi are more resistant to acid and dry conditions than bacteria, and it is hypothesised that the aerial mycelia of fungi, which are in direct contact with the gas, can take up hydrophobic compounds faster than flat aqueous bacterial biofilm surfaces. Alpha-pinene was chosen as a model compound. It is an odorous compound emitted by the wood processing industry. In 2 l biofilter columns four different packing materials were tested: perlite, expanded clay granules, polyurethane foam cubes and compost. The filters were inoculated with forest soil and ventilated with gas containing alpha-pinene. Start up took 1-2 months and removal efficiencies of more than 90% were observed, but mostly ranged from 50% to 90% due to overloading. In the filters containing perlite, clay, polyurethane and compost volumetric removal capacities of, respectively, 24, 33, 38 and 24 g alpha- pinene m -3 filter bed h -1 were attained and the gas pressure drops in the 60 cm high filter beds measured at a superficial gas velocity of 35 m h -1 were 70, 550, 180 and 250 Pa. The results indicate that it is possible to develop biofilters based on the action of fungi with higher elimination capacities for alpha-pinene as reported in literature for bacterial biofilters. The use of polyurethane foam cubes is preferred because of the low gas pressure drop in combination with a high volumetric elimination capacity.

  13. EFEKTIVITAS SISTEM BIOFILTER AEROB DALAM MENURUNKAN KADAR AMONIA PADA AIR LIMBAH

    Directory of Open Access Journals (Sweden)

    Ni Made Indra Wahyuni

    2015-06-01

    Full Text Available The increasingpopulationand activity of the Balinese people can increase the amount of waste as a byproduct of community activities. The presence of the metabolites in wastewater as ammonia is toxic to aquatic organisms. Application aerobic biofilter system can be used as an attempt to reduce levels of ammonia. In the aerobic biofilter, contact between the gravel media with microorganisms that form biofilmsare able to accelerate the degradation of organic matter and nitrification processes. The aims of this research are to determine the best consortium of activated sludge to reduce ammonia levels by aerobic biofilter system and to determine the effectivity of aerobic biofilter system. The first stage of this research were seeding of activated sludge from three sources are Wastewater Treatment Plan (WWTP of Suwung Denpasar, WWTP of Wangaya Hospital and WWTP of Bali Tourism Development Corporation (BTDC Nusa Dua Bali, for six days. This research was done by measuring Volatile Suspended Solid (VSS value that showed the growth rate of biomass in activated sludge. The second stage wereapplication of activated sludges and control in aerobic biofilter to reduce ammonia levels, for five days. This study used a Completely Randomized Design with four treatments and three repetitions. The results showed that the best activated sludge obtained from WWTP of Suwung Denpasar indicated by the highest biomass growth (VSS value of 2396.6 mg/L and was able to reduce ammonia up to 0.78 mg/ L. The effectivity of aerobic biofilter system with activated sludge from WWTP of Suwung Denpasar achieve effectivity of treatment process up to 92.20 % and have been able to pass the effectivity of quality standards (90% during five days of processing. The effectivity levels was the highest compared to control and activated sludgetreatments.

  14. Onkologie und Nervensystem

    Directory of Open Access Journals (Sweden)

    Grisold W

    2009-01-01

    Full Text Available Die Zusammenhänge zwischen dem Nervensystem und onkologischen Erkrankungen beschränken sich nicht nur auf primäre Hirntumoren, sondern gewinnen bei zahlreichen Tumorerkrankungen, einerseits aufgrund der verbesserten Überlebenszeit, andererseits aufgrund von therapiebedingter Neurotoxizität, an Bedeutung. Es handelt sich um direkte Tumoreinwirkungen wie Metastasen oder meningeale Ausbreitungen, Auswirkung der Therapie im Sinne von Neurotoxizität, metabolischen Phänomenen, Infektionen und paraneoplastische Syndrome. Besondere Bedeutung verdient die Kontrolle von symptomatischen Anfällen und die Behandlung von Schmerzen bei onkologischen Patienten. Supportive und palliative Maßnahmen gewinnen zwar zunehmend an Bedeutung, sind aber in der Neurologie noch weitgehend in Entwicklung. Vertieftes Wissen über neurologische Störungen bei onkologischen Patienten im Sinne einer neuroonkologischen Qualifikation ist anzustreben.

  15. Niere und Hypertonie

    Directory of Open Access Journals (Sweden)

    Watschinger B

    2004-01-01

    Full Text Available Eine Hypertonie kann Ursache, aber auch Folge einer Nierenerkrankung sein. Der Blutdruck trägt zur Progression der renalen Erkrankung und zum exzessiv hohen kardiovaskulären Risiko der Patienten bei. Der Zielblutdruck bei Patienten mit einer eingeschränkten Nierenfunktion oder gleichzeitig bestehender Proteinurie unter 1 g/Tag liegt bei 130/80 mmHg, bei einer Proteinurie über 1 g/Tag 125/75 mmHg und bei Patienten mit diabetischer Nephropathie 130/80 mm Hg. ACE-Hemmer oder ARB sind Mittel der 1. Wahl, da sie stärker als andere Substanzen antiproteinurisch wirken. Um die Zielblutdruckwerte zu erreichen, ist jedoch meist eine antihypertensive Kombinationstherapie (evt. mit Diuretika und/oder Nicht-Dihydropyridin-Kalziumantagonisten, bzw. Kombination von ACE-Hemmer und ARB erforderlich.

  16. Therapieeskalation: Wann und wie?

    Directory of Open Access Journals (Sweden)

    Lutterotti A

    2010-01-01

    Full Text Available Für Patienten mit Multipler Sklerose, für die mit einer immunmodulierenden Basistherapie keine ausreichende Verminderung der Krankheitsaktivität erreicht werden kann, ist eine Eskalationstherapie vorgesehen. Man geht davon aus, dass bei diesen Patienten eine frühe und effektive Intensivierung der Immuntherapie die entzündliche Krankheitsaktivität hemmen kann und die langfristige Prognose günstig beeinflusst. Es stehen verschiedene monoklonale Antikörper und immunsuppressive Substanzen zur Verfügung, allerdings gibt es nur zum Teil gute Evidenz aus kontrollierten Studien. In diesem Übersichtsartikel gehen wir auf die Rationale für den Beginn einer Eskalationstherapie ein und diskutieren die unterschiedlichen Substanzen.

  17. Wasserball und Kommunismus

    NARCIS (Netherlands)

    Celikates, R.

    2010-01-01

    Zuletzt recht medienwirksam verbreiten Philosophen wie Slavoj Žižek und Alain Badiou eine vage «kommunistische Hypothese» - wie sehen die Theoriealternativen zu dieser neokommunistischen Intervention aus, die zugleich eine Abkehr vom Marxismus ist?

  18. Supraleitung Grundlagen und Anwendungen

    CERN Document Server

    Buckel, Werner

    2004-01-01

    Seit nunmehr drei Jahrzehnten ist der "Buckel" das Referenzwerk in deutscher Sprache zum Thema Supraleitung. Immer wieder aktualisiert, hat das Lehrbuch Generationen von Studenten begleitet. In der 6., vollständig überarbeiteten Auflage wird das bewährte didaktische Konzept beibehalten, inhaltlich wurde der Band dem aktuellen Stand von Forschung und Technik angepasst. Das Autorenteam um Prof. Kleiner verzichtet auf komplizierte mathematische Herleitungen. Es baut ganz auf das bewährte Step-by-Step-Prinzip: Der Schwierigkeitsgrad wird von Kapitel zu Kapitel gesteigert. So können auch Einsteiger ohne einschlägige Vorkenntnisse dem Stoff bequem folgen. Dank seiner klaren Sprache und zahlreicher Abbildungen eignet sich der Band hervorragend als einführendes Lehrbuch - und zwar nicht nur für Physik-Studenten, sondern auch für Studierende angrenzender Natur- und Ingenieurwissenschaften. Grundlegende Eigenschaften, supraleitende Elemente, Cooper-Paarung, Thermodynamik, kritische Ströme, Josephsonkontakte...

  19. Aerobic biofilters with small synthetic grains for demostric wastewater treatment: kinetics, efficiency and microbial deviersity

    Energy Technology Data Exchange (ETDEWEB)

    Nacheva, M.; Moeller-Chavez, G.; Hornelas-Orozco, Y.; Bustos, C.

    2009-07-01

    The aerobic biofilters with submerged packaed bed are able to retain a large biomass quantity, which makes them compact and suitable for samll wastewater treatment plants. The characteristics of the packed bed determine the structure of the formed biofilms, the operation mode and the effectiveness. The objective of this work was to compare the biofilm kinetics and the microbial diversity in three aerobic biofilters packed with grains 3.0-4.5 mm) made of high and of low density polyethylene (HDPE and LDPE), and of polypropyline (PP). The experimental work was carried out using three 20 L reactors, operated in downflow mode. (Author)

  20. Development of biofilters to treat the pesticides wastes from spraying applications.

    Science.gov (United States)

    Pigeon, O; de Vleeschouwer, C; Cors, F; Weickmans, B; de Ryckel, B; Pussemier, L; Debongnie, Ph; Culot, M

    2005-01-01

    Several studies carried out in Europe showed the importance of direct losses to the contamination of surface water by pesticides. These pesticides losses can occur at the farm site when the sprayer equipment is filled with the pesticide formulation (spills, overflowing, leaking) and during the clean-up (rinsing) of the sprayer after the treatment. In Belgium studies are carried out on biofilters to treat in an efficient way effluents containing pesticides. The biofilter substrate is elaborated from a homogenised mixture of local soil, chopped straw and peat or composted material, able to absorb or degrade the active substances. Biofilters consist in systems of 2 or 3 units depending on the spray equipment of the farmer and on the configuration of the farmyard. Each unit is made from a 1 m3 plastic container and the different units are stacked in a vertical pile and connected between them using plastic valves and pipes. Eight pilot systems were installed in March 2002 in seven farms and in one agricultural school, all selected in the loamy region of Belgium specialised in arable crops such as cereals, sugar beets and vegetables. The efficacy (yield) of the systems was determined by measuring the balance of the inputs and outputs of the pesticides. Results were expressed in percent of pesticide retained on the biofilters. The results obtained after two years with 5 tracer pesticides (atrazine, carbofuran, diuron, lenacil and simazine) brought on the biofilter installations are very satisfactory since the percentage of retention is generally higher than 95% of the amount applied. In the beginning of 2004, ten new pilot biofilters were installed in several farms or agricultural technical centres (producing cereals, sugar beets, potatoes, vegetables, fruits or ornamental plants), and in a municipal maintenance service. Some biofilters were installed in duplicate in order to compare the efficacy of different substrates. The efficacy of the biofilters was studied for the

  1. Degradation and effect of hydrogen peroxide in small-scale recirculation aquaculture system biofilters

    DEFF Research Database (Denmark)

    Møller, Martin Sune; Arvin, Erik; Pedersen, Lars-Flemming

    2010-01-01

    From an environmental point of view, hydrogen peroxide (HP) has beneficial attributes compared with other disinfectants in terms of its ready degradation and neutral by-products. The rapid degradation of HP can, however, cause difficulties with regard to safe and efficient water treatment when......−1 maintained over 3 h had a moderate inhibitory effect on the biofilter elements from one of the RAS with relatively high organic loading, while the nitrification was severely inhibited in the pilot-scale biofilters from the other RAS with a relatively low organic loading. A pilot-scale RAS...

  2. Hypertonie und Adipositas

    Directory of Open Access Journals (Sweden)

    Abrahamian H

    2001-01-01

    Full Text Available Adipositas ist eine komplexe, multifaktorielle Erkrankung, die häufig mit Hypertonie assoziiert ist. Daten aus der Framingham-Studie zeigen, daß bei 78 % der Männer und bei 65 % der Frauen mit essentieller Hypertonie die Adipositas als ursächlich dafür betrachtet werden kann. Die dafür verantwortlichen pathophysiologischen Mechanismen sind ungenügend aufgeklärt und daher vielfach noch spekulativ. Die Hypothese, daß die Insulinresistenz als hauptverantwortlicher Faktor für die Entstehung der Hypertonie bei adipösen Patienten zu betrachten ist, wird in zahlreichen Studien durch signifikante Korrelation zwischen Insulinspiegel und Hypertonie belegt. Jedoch hat sich mehrfach gezeigt, daß diese Korrelationen mit hoher Wahrscheinlichkeit speziesabhängig sind. Ob nun bei Menschen ein kausaler Zusammenhang zwischen Hypertonie und Insulinresistenz angenommen werden kann, bleibt hypothetisch. Die Kausalität dieser engen Assoziation könnte in 4 Mechanismen begründet sein: Natrium-Retention, Hyperaktivität des sympathischen Nervensystems, gestörter membranöser Ionen-Transport und Proliferation von glatten Gefäß-Muskelzellen. In einem Vergleich zwischen hypertensiven und normotensiven alters- und gewichtsgematchten Probanden zeigte sich, daß hypertensive Patienten generell einen erhöhten Insulin-Response nach Glukose-Belastung aufwiesen. Dieser Effekt konnte unabhängig vom Körpergewicht nachgewiesen werden. Eine weitere Untersuchung, die bei jungen, schlanken Hypertonikern eine deutliche Verringerung der Insulin-induzierten Glukose-Aufnahme in einem Clamp-Versuch findet, bestätigt dieses Ergebnis. Andere Erklärungsansätze für die Assoziation Adipositas und Hypertonie sind erhöhter Leptinspiegel, ein TNF-Alpha-Genlocus für Adipositas und Hypertonie und ein im Fettgewebe lokal wirksames RAS. Als therapeutische Intervention steht die Gewichtsreduktion an erster Stelle, wobei hier auch der Einsatz von Medikamenten wie Appetitz

  3. Measurement and modelling of local phenomena in polymer electrolyte fuel cells; Messung und Modellierung lokaler Phaenomene in Polymer-Elektrolyt-Brennstoffzellen

    Energy Technology Data Exchange (ETDEWEB)

    Eckl, R.

    2007-05-15

    Within the scope of this thesis, a new method for in situ current distribution measurement based on printed circuit board technology is developed and applied to polymer electrolyte fuel cells. Using the finite element method, the accuracy of this new approach is compared to conventional techniques and an estimate of the maximum uncertainty of measurement due to lateral currents is given. The effects of variable operating parameters on local electrochemical performance are studied by stationary and dynamic testing of laboratory cells with 100 cm{sup 2} active area. Based on experimental results, load conditions on the anode side are modelled and characteristic water management issues are analysed with the aid of computational fluid dynamics (CFD) simulations. (orig.)

  4. Interdiffusion of the aluminum magnesium system. Quantitative analysis and numerical model; Interdiffusion des Aluminium-Magnesium-Systems. Quantitative Analyse und numerische Modellierung

    Energy Technology Data Exchange (ETDEWEB)

    Seperant, Florian

    2012-03-21

    Aluminum coatings are a promising approach to protect magnesium alloys against corrosion and thereby making them accessible to a variety of technical applications. Thermal treatment enhances the adhesion of the aluminium coating on magnesium by interdiffusion. For a deeper understanding of the diffusion process at the interface, a quantitative description of the Al-Mg system is necessary. On the basis of diffusion experiments with infinite reservoirs of aluminum and magnesium, the interdiffusion coefficients of the intermetallic phases of the Al-Mg-system are calculated with the Sauer-Freise method for the first time. To solve contradictions in the literature concerning the intrinsic diffusion coefficients, the possibility of a bifurcation of the Kirkendall plane is considered. Furthermore, a physico-chemical description of interdiffusion is provided to interpret the observed phase transitions. The developed numerical model is based on a temporally varied discretization of the space coordinate. It exhibits excellent quantitative agreement with the experimentally measured concentration profile. This confirms the validity of the obtained diffusion coefficients. Moreover, the Kirkendall shift in the Al-Mg system is simulated for the first time. Systems with thin aluminum coatings on magnesium also exhibit a good correlation between simulated and experimental concentration profiles. Thus, the diffusion coefficients are also valid for Al-coated systems. Hence, it is possible to derive parameters for a thermal treatment by simulation, resulting in an optimized modification of the magnesium surface for technical applications.

  5. Mechanistic investigation and modelling of anode reaction in the molten carbonate fuel cell; Mechanistische Untersuchung und Modellierung der Anodenreaktion in der Karbonat-Brennstoffzelle

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, Markus Roman

    2011-04-27

    Considering distributed energy generation, molten carbonate fuel cells (MCFCs) have best prospects to fulfil the demands of the highly competing energy market. To establish MCFC technology in the market, various requirements need to be met. These are on the one hand the reduction of the specific costs per kW and the simultaneous increase in efficiency of the MCFCs. On the other hand, an extended lifetime of MCFC stacks in general and especially when biofuels are used is required. Detailed knowledge of electrodes' reaction mechanisms is essential for successful technical improvements or cost reduction measures. In this thesis, the complex anodic reaction mechanism in the molten carbonate fuel cell is studied in detail, with the objective to develop a fundamental understanding of the physical and electrochemical processes taking place at the anode, and to identify the factors influencing the performance of fuel cell stacks. These include a detailed study of the simultaneously performed oxidation reactions of hydrogen and carbon monoxide and its kinetic parameters, the detailed analysis of mass transport, adsorption and charge transfer and the observation of degradation phenomena, which have a declining effect on cell performance and lifetime. In order to gain this knowledge, several testing facilities have been used: anode half-cells and single cells. Electrochemical impedance spectroscopy (EIS) has been applied as analyzing tool for physical and electrochemical phenomena, whose results have been integrated in the development of an equivalent circuit. Linking the elements of the equivalent circuit with physical process parameters has been done by using a numerical model for the MCFC-anode. The impedance measurements of the MCFC anodes result in four characteristic resistances: ohmic resistance, high-frequency resistance, low-frequency resistance and cumulative resistance. The strongly temperature dependent high-frequency resistance is influenced by the electrode kinetics, while the mass transfer is expressed by the low-frequency resistance. The results of this study show, that the anodic reaction mechanisms for the hydrogen oxidation, postulated in the literature are incomplete. The oxidation of hydrogen follows a reaction rate of pseudo-negative order. A prerequisite requirement for this purpose is two adsorbing species and a bimolecular reaction step. By using numerical simulation it is found, that a parallel adsorption of hydrogen and hydroxide-ions at the anode is probable. In addition, no effect concerning the carbon monoxide oxidation at the anode can be detected, so that a carbon monoxide formation by the faster shift equilibria can be assumed. Experimental studies show two temperature ranges with different activation energies concerning the MCFC-anode. This enables the identification of diffusion and kinetically limited intervals with different pore efficiency factors. By using numerical methods, it can be shown that the characteristic resistances of the anode can be reproduced precisely with a suitable choice of conductivity, reaction rate and mass transfer approaches. The outcome of this thesis can be used for the development of the MCFC anode, as well as for an input into numerical models, that describe a MCFC stack and predict temperature distributions over the cell surface. (orig.) [German] Im Bereich dezentraler Energieversorgung werden der Schmelzkarbonat-Brennstoffzelle (MCFC) beste Aussichten bescheinigt, die Anforderungen des stark konkurrierenden Energiemarkts zu erfuellen. Die Markteinfuehrung der MCFC-Technologie erfordert die Erfuellung verschiedenster Anforderungen. Dazu gehoert zum einen die Reduzierung der spezifischen Kosten pro Kilowatt bei gleichzeitiger Erhoehung der Effizienz. Andererseits wird eine erhoehte Lebensdauer der MCFC-Stapel, insbesondere bei Verwendung biogener Brennstoffe, gefordert. Grundvoraussetzungen fuer erfolgreiche technische Verbesserungen oder Massnahmen zur Kostenreduktion sind detaillierte Kenntnisse der an den Elektroden ablaufenden Reaktionsmechanismen. In der vo

  6. Modelling and simulation of pixelated photon counting X-ray detectors for imaging; Modellierung und Simulation physikalischer Eigenschaften photonenzaehlender Roentgenpixeldetektoren fuer die Bildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Durst, Juergen

    2008-07-22

    First of all the physics processes generating the energy deposition in the sensor volume are investigated. The spatial resolution limits of photon interactions and the range of secondary electrons are discussed. The signatures in the energy deposition spectrum in pixelated detectors with direct conversion layers are described. The energy deposition for single events can be generated by the Monte-Carlo-Simulation package ROSI. The basic interactions of photons with matter are evaluated, resulting in the ability to use ROSI as a basis for the simulation of photon counting pixel detectors with direct conversion. In the context of this thesis a detector class is developed to simulate the response of hybrid photon counting pixel detectors using high-Z sensor materials like Cadmium Telluride (CdTe) or Gallium Arsenide (GaAs) in addition to silicon. To enable the realisation of such a simulation, the relevant physics processes and properties have to be implemented: processes in the sensor layer (provided by EGS4/LSCAT in ROSI), generation of charge carriers as electron hole pairs, diffusion and repulsion of charge carriers during drift and lifetime. Furthermore, several noise contributions of the electronics can be taken into account. The result is a detector class which allows the simulation of photon counting detectors. In this thesis the multiplicity framework is developed, including a formula to calculate or measure the zero frequency detective quantum efficiency (DQE). To enable the measurement of the multiplicity of detected events a cluster analysis program was developed. Random and systematic errors introduced by the cluster analysis are discussed. It is also shown that the cluster analysis method can be used to determine the averaged multiplicity with high accuracy. The method is applied to experimental data. As an example using the implemented detector class, the discriminator threshold dependency of the DQE and modulation transfer function is investigated in detail for Silicon and CdTe as sensor materials. For CdTe these results are shown beside the energy response spectrum for an ideal energy deposition detector, the ideal response of a Medipix2 detector and for the charge summing mode of the Medipix3 detector. (orig.)

  7. Diesel engine soot and No{sub x} emission modeling; Modellierung der Russ- und NO{sub x}-Emissionen des Dieselmotors

    Energy Technology Data Exchange (ETDEWEB)

    Wenzel, S.P. [Robert Bosch GmbH, Stuttgart (Germany); Willmann, M. [Volkswagen Nutzfahrzeuge, Wolfsburg (Germany); Tschoeke, H. [Magdeburg Univ. (Germany); Harndorf, H. [Rostock Univ. (Germany)

    2008-07-01

    It has been demonstrated that soot and NO{sub x} emissions can be calculated based on 6 'global' parameters describing rate of heat release and gas mixture. This method is valid for a wide engine map as well as for heterogeneous and partially homogeneous combustion. After adapting the model coefficients the models are transferable to different passenger cars diesel engines with different injection systems, different cylinder displacements and valve arrangements. Recommendations for low pollutant combustion can be derived from the soot and NO{sub x} models: an ideal rate of heat release characterised by a smooth rise until maximum, a moderate maximum cylinder peak pressure rise and a fast decline. Such an 'ideal' rate of heat release can be achieved e.g. by injection rate shaping. Long ignition delays caused by high EGR rates and early start of injections are favourable for a partially homogeneous combustion. Increased boost pressure leads to a higher EGR capacity due to the higher oxygen concentration in the cylinder. As all model input parameters can be measured with standard measurement technique it is possible to include the models in future engine ECUs. (orig.)

  8. Modelling and monitoring of the transport of dissolved substances in tidal water. Modellierung und Ueberwachung des Transportes geloester Stoffe in Tidegewaessern

    Energy Technology Data Exchange (ETDEWEB)

    Kappenberg, J.

    1987-12-18

    It was tried with simple model attempts to simulate the mechanisms of pollutant transportation in tide rivers (Elbe) and to control the water quality by means of monitoring systems. In particular, there were developed explicit models for the hydrodynamics in a channel-like river section in explicit (EXKA and ERKA) and implicit (IMKA) forms. The refined model MKMO was developed, in which the river is simulated by a number of parallel channels, as well as the model HAFEN, representing a network of channels and arms of rivers as it is typical for the Hamburg harbour. The physical transport was simulated partially in fixed (Euler-)coordinates (model EUTR) partially in a grid, which was transported by the current (Lagrangian coordinates, model LATR). The biochemical oxygen degradation was first simulated by combining all oxygen consumers in the BOD (biological oxygen demand) with a simple nonlinear Streeter-Phelps model. Then, a more accurate model was made of the oxygen depletion by organic nitrogen oxidation (nitrification), which is of special importance in the Elbe.

  9. Modeling and simulation of the effective behaviour of interfaces in alloys; Modellierung und Simulation des effektiven Verhaltens von Grenzflaechen in Metalllegierungen

    Energy Technology Data Exchange (ETDEWEB)

    Lenz, M.

    2007-07-15

    This thesis is concerned with the modeling and the numerical simulation of phase transitions during the Ostwald ripening of metal alloys and in magnetic shape memory materials. The phase transition is modeled on a continuum level with methods of elasticity theory. The coarsening of particles in a metal alloy after spinodal decomposition can be seen as a gradient flow: The set of particles moves on the manifold of all possible particle configurations in the direction of steepest descent of an energy functional containing interface energy and elasticity, with respect to a metric tensor describing the diffusion mechanism. The restriction of this evolution onto the submanifold of rectangular particles aligned to the coordinate axes, as they are preferred by the anisotropy of the elasticity tensor, gives a reduced model that describes the evolution of such particles. The numerical simulation of both models employs the boundary element method. The integral operators occurring are approximated by hierarchical matrices, this approximation also gives an appropriate preconditioner. To avoid the coupling of the time step size to the side length of the smallest particle, one uses localized timesteps close to small particles, where the screening effect makes it possible to restrict to small neighbourhoods of the respective particle. In this way one constructs an efficient method to simulate both models; in the reduced model accordingly the simulation of larger particle ensembles is possible. Comparative computations verify that the reduced model reproduces many important qualitative and quantitative properties of the full model. Magnetic shape memory materials can be modeled on a continuum scale using a combination of elasticity and micromagnetism. Here, a discrete phase parameter couples the variants of the elastic strain to the magnetic anisotropy. The anisotropy prefers a magnetization in the direction of contraction. This model can be applied to the description of several types of microstructured material: composites with a non-magnetic background matrix and polycrystalline structures. To compute the effective behaviour of the micro structure, one considers cell problems in the spirit of homogenization theory. The numerical solution of these cell problems uses again the boundary element method, here embedded in a descent algorithm for energy minimization. Thereby the influence of parameters of the microscopic structure of the material, such as form, distribution and shape of particles or the elasticity of the background matrix, on the macroscopic behaviour, especially the observed strain and the work output, can be quantified. (orig.)

  10. TOM - Manufacture and modelling of a demonstration oxide module; TOM, Erstellen und Modellierung eines thermo-elektrischen oxidischen Moduls (TOM) als Demonstrator - Jahresbericht 2007

    Energy Technology Data Exchange (ETDEWEB)

    Tomes, P.; Weidenkaff, A.

    2007-07-01

    This annual report for the Swiss Federal Office of Energy (SFOE) takes a look at the work done at the Swiss Federal Laboratories for Materials Science and Technology EMPA in 2007 on demonstrating the thermoelectric effects of an oxide module. Four-leg oxide-based thermoelectric modules are described which have been produced by combining p and n-type oxide elements. The modules were assembled using a mixture of silver paste along with silver and copper oxide powders. Three types of thermoelectric oxide modules with different thermocouple leg-lengths were examined. In this type of module, p and n-type semiconductor thermocouples are connected electrically in series by highly conducting metal strips using silver with copper oxide and sandwiched between thermally conducting but electrically insulating plates made of corundum. The results obtained are presented in graphical form and discussed.

  11. Modeling of flow and mass transport processes in unsaturated soils in combination with technical facilities; Modellierung von Stroemungs- und Stofftransportprozessen bei Kombination der ungesaettigten Bodenzone mit technischen Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    Hasan, Issa

    2014-07-01

    The modelling of complex systems such as the underground is a means to describe the processes occurring in the reality. The conducting of experiments on a model to obtain qualitative evidence about a real system is referred to as a simulation. Thereby, various models (e.g. physical and mathematical models) can be used. The unsaturated zone (vadose zone) is the region between the land surface and the water table, in which the water content is less than full saturation, and the pressure is lower than the atmospheric pressure. The unsaturated zone is very significant for agriculture, geobiology, aerobic degradation processes and groundwater recharge. The processes of water flow and solute transport in the unsaturated zone can be described by means of numerical simulation programs. The aim of the present work is a comprehensive validation of the simulation program PCSiWaPro {sup registered} (developed at the TU-Dresden, Institute of Waste Management and Contaminated Site Treatment) for different applications. Another aim of this work is to investigate the applicability of the current version of PCSiWaPro {sup registered} for different cases of a combination between the unsaturated zone and technical facilities. Four application cases with different objectives were investigated within the present work, which are: the simulation of decentralized wastewater infiltration with corresponding column and field experiments, the computation of groundwater recharge by means of lysimeters, the water balance of earth dams and the modelling of landfill covering systems. The application cases differ from each other by the objective of the simulation, the geometry, the size, the specified initial and boundary conditions, the simulation time, the applied materials, the coordinate system, the input and output data. The simulation results clearly showed that PCSiWaPro {sup registered} is applicable for all investigated cases under consideration of different flow and solute transport regimes, parameters, boundary conditions, spatial and temporal discretization, and coordinate systems. The simulation results of the experimental soil columns for the decentralized treated wastewater infiltration case showed a very good agreement between measured and computed values of water and solute balance (pressure head, flow and solute concentration) of the investigated soil types B3 (slightly silty sand), B4 (coarse sand / gravel) and B5 (medium silty sand). The root of the mean squared error (RMSE) for the computation of the pressure head was 1,84 cm at B5, 3,61 cm at B3 and 1,27 cm at B4. The relative deviation in case of pressure head computation was 2,19 % at B5, 1,3 % at B3 and 5,3 % at B4. The implementation of the sensitivity analysis of the relevant parameters for the modelling showed a very high sensitivity of the VAN GENUCHTEN parameters and the saturated hydraulic conductivity of the soil. Moreover, the parameters according to DIN 4220 led to different results than the estimated ones according to pedotransfer methods based on sieve analysis. Within the project EGSIM, which was carried out at the Institute for waste management and contaminated sites treatment in collaboration with DUALIS GmbH IT Solution, the programs SENSIT and ISSOP were developed and used for parameter identification/calibration. The results obtained in this Work showed under which conditions is a secondary treatment of full biologically treated wastewater in the soil possible, so that no unallowable pollutants entry in the groundwater occurs. With regard to the field models of this application the implementation of the rotationally symmetric coordinate system should be considered as a condition and not as an option for a better corresponding to the reality. Furthermore, different scenarios of the field models were carried out with continuous and discontinuous infiltration, as well as under different initiation areas. PCSiWaPro {sup registered} could be applied for both unsaturated and variably-saturated porous media. This could be proven by the simulation of the water balance in an earth dam. The average relative deviation between measured and simulated water levels of the corresponding observation point in the investigated dam embankment was 0,08 % (corresponding to 5,8 cm at 70 m thickness) and the coefficient of determination (R{sup 2}) was 0,987. In general, the simulation of the water balance using PCSiWaPro {sup registered} of different landfill covering systems showed a successful draining of the falling rainwater (even under heavy rainfall). In addition, the implemented vegetation models have proven that the vegetation of the landfill surface can reduce the water content in the landfill by evapotranspiration and water uptake by roots. The water balance simulation results of the scenarios for the computation of groundwater recharge by means of lysimeters showed that the program is applicable for this case. The relative deviation of the simulated from the measured groundwater recharge rates occur due to the implemented material parameters as well as to the neglect of macro pores effects (dual porosity).

  12. Mesoscale modeling of the production and the three-dimensional transport of nitrogen oxides in thunderstorms; Mesoskalige Modellierung der Produktion und des dreidimensionalen Transports von Stickoxiden durch Gewitter

    Energy Technology Data Exchange (ETDEWEB)

    Fehr, T.

    2000-07-01

    Nitrogen oxides, NO{sub x} = NO + NO{sub 2}, play a fundamental role in tropospheric chemistry. Compared to other sources, the contribution of lightning induced NO{sub x} (LNO{sub x}) is known with considerable uncertainties and difficult to determine experimentally. The distribution of nitrogen oxides in an isolated thunderstorm is investigated using a modified version of the Penn State/NCAR Mesoscale Model (MM5) with cloud-scale resolution. A Lagrangian particle model has been developed to represent the NO{sub x} released by individual flashes. The position of the flash, the flash type, the geometrical properties of the channel, and the amount of emitted NO{sub x} are introduced to the MM5 in a parameterized form. On July 21, 1998, during the European lightning nitrogen oxides project (EULINOX) field campaign, a supercell development was observed in the German alpine foreland. Anvil penetrations by the DLR Falcon aircraft contributed high resolution profiles of NO{sub x}. DLR radar observation covered the complete life cycle of the thunderstorm. The lightning activity was recorded with a lightning positioning and tracking system (LPATS) run by local power suppliers, while radiosonde and aircraft measurements supplied detailed information on the atmospheric stratification ahead of the thunderstorm. This meteorological information was used to initalize a cloud-scale MM5 simulation. The modeled thunderstorm reproduces many observed properties, e.g. cell splitting, propagation speed and direction, anvil and overshooting top height, and WER (weak echo region). The number of simulated cloud-to-ground flashes, as well as the temporal evolution of the lightning activity are comparable to the LPAT observations. The general transport properties of the model thunderstorm are investigated using an inert PBL-tracer, as well as trajectory analysis. The simulated lightning activity leads to the release of approximately 1 000 000 NO{sub x}-particles. The thunderstorm produces 28.7 t of oxidized nitrogen, 66% resulting from cloud-to-ground lightning. One hour after the lightning activity had terminated, a total of 15 t is found in the anvil altitude. Extrapolated to a global LNO{sub x}-production rate, the results of the simulation would imply that LNO{sub x} is by far the most dominant NO{sub x}-source. However, the model thunderstorm case was unusual for the region. The comparison between the observed and modeled anvil NO{sub x}-profiles shows many similarities in structure and absolute values. This can help to estimate the uncertainties involved with extrapolating aircraft NO{sub x}-measurements to a NO{sub x}-production rate. As a conclusion, the MM5 thunderstorm simulation with a Lagrangian particle representation for LNO{sub x} is capable to reproduce significant microphysical and chemical observations, and can help to estimate the impact of lightning on the tropospheric NO{sub x} budget. (orig.)

  13. Soziale Faktoren und Arbeitssicherheit

    OpenAIRE

    Krause-Jüttler, Grit

    2011-01-01

    Die Dissertation setzt sich mit der Thematik der Arbeitssicherheit in produzierenden kleinen und mittelständischen Unternehmen der sächsischen Metall- und Feinmechanikindustrie auseinander. Dabei untersucht die Autorin mögliche Einflussfaktoren auf das Sicherheitsverhalten von Arbeitnehmer/innen, um Hinweise für verbesserte personalwirtschaftliche Methoden zu identifizieren. Dabei liegt der Schwerpunkt der Arbeit auf dem Einfluss, den direkte Kolleg/innen auf das individuelle Sicherheitsverha...

  14. Epilepsiechirurgie und Neurostimulation

    Directory of Open Access Journals (Sweden)

    Baumgartner C

    2009-01-01

    Full Text Available Zirka 35 % aller Epilepsiepatienten leiden an einer medikamentös therapieresistenten Epilepsie. Für diese Patienten stellen die Epilepsiechirurgie (als potenziell kurative Methode und Neurostimulationsverfahren (als palliative Verfahren wertvolle Behandlungsoptionen dar. Bei den epilepsiechirurgisch behandelbaren Epilepsiesyndromen lassen sich (1 Epilepsien mit fokalen Pathologien, bei denen eine umschriebene Resektion durchgeführt werden kann; (2 Epilepsien, die extensive, oft multilobäre Resektionen oder Hemisphärektomien erfordern und (3 Epilepsien, bei denen lediglich eine Diskonnektionsoperation sinnvoll ist, unterscheiden. Voraussetzung für einen epilepsiechirurgischen Eingriff ist eine exakte präoperative Epilepsiediagnostik, wobei die epileptogene Zone und essenzielle Hirnregionen genau lokalisiert werden müssen. Dadurch werden prognostische Aussagen bezüglich der postoperativen Anfallskontrolle und eine Abschätzung des Risikos funktioneller Defizite ermöglicht. Gemäß einer rezenten Metaanalyse ist der mediane Anteil der langfristig anfallsfreien Patienten nach Temporallappenresektionen 66 %, nach okzipitalen und parietalen Resektionen je 46 % und nach frontalen Resektionen 27 %. Die Vagus- Nerv-Stimulation (VNS ist eine klinisch etablierte Methode für Patienten, die für einen epilepsiechirurgischen Eingriff nicht infrage kommen oder bei denen eine solche Operation nicht zum Erfolg geführt hat. Mit der VNS können Responderraten (Anfallsreduktion 50 % von 30–40 % erzielt werden, wobei die Wirksamkeit über die ersten 18–24 Monate kontinuierlich zunimmt, um dann ein stabiles Plateau zu erreichen. Bei der direkten Hirnstimulation, die sich derzeit noch im experimentellen Stadium befindet, kann einerseits eine direkte Stimulation der epileptogenen Zone und somit kortikaler Strukturen erfolgen, andererseits können auch tiefe Hirnstrukturen mit dem Ziel der Modifikation der Anfallsentstehung und/oder Ausbreitung stimuliert

  15. Sprichwort und Wortspiel

    Directory of Open Access Journals (Sweden)

    Željka Matulina

    1994-12-01

    Full Text Available Als eine idiomatische Bildung mit dem Satz-Status wird das Sprichwort meist aus der lexikographischen Diskussion ausgeschlossen, weil es Satz ist, auf der anderen Seite wird es im Rahmen der Syntax nicht behandelt, weil es Idiom ist, und so hat das Überprüfen und Testen seiner grammatischen Strukturiertheit wenig Sinn. Die Spezifik des Sprichwort-Satzes liegt in der linear-horizontalen Kombinatorik seiner Konstituenten. Die Reihenfolge der Sprichwort-Konstituenten ist streng festgelegt.

  16. Psychopharmaka und sexuelle Dysfunktion

    Directory of Open Access Journals (Sweden)

    Assem-Hilger E

    2005-01-01

    Full Text Available Moderne psychopharmakologische Therapieansätze reduzieren psychiatrische Zielsymptome und berücksichtigen in zunehmendem Maße prognostisch bedeutsame Faktoren wie subjektive Lebensqualität und soziale Reintegration. Im Rahmen der Complianceforschung wurden in den letzten Jahren sexuelle Nebenwirkungen von Psychopharmaka, insbesondere von antidepressiven und antipsychotischen Substanzen, vermehrt untersucht. Die komplexen Wechselwirkungen zwischen psychosozialen, biologischen und pharmakologischen Faktoren im Rahmen psychiatrischer Erkrankungen können die ätiologische Zuordnung sexueller Dysfunktionen erschweren. Als gesichert gilt jedoch, daß Substanzen mit vorwiegend serotonergem Wirkmechanismus mit vergleichsweise hohen Inzidenzen sexueller Nebenwirkungen assoziiert sind. Substanzen mit postsynaptischer Serotonin-2-Rezeptorblockade oder alpha-adrenolytischer Wirkkomponente zeichnen sich hingegen durch das weitgehende Fehlen sexueller Dysfunktionen aus. Innerhalb der Gruppe der Antipsychotika sind sexuelle Nebenwirkungen vor allem bei Präparaten mit ausschließlicher oder vorwiegender Dopamin-2-Rezeptorblockade und damit assoziierten endokrinologischen Nebenwirkungen zu erwarten. Bei Auftreten iatrogen induzierter Sexualstörungen sind gegenregulierende Maßnahmen stets nach strenger individueller Nutzen-Risiko-Abwägung zu treffen. Der vorliegende Artikel bietet einen Überblick über die aktuelle Literatur zu Pathophysiologie, Inzidenz und klinischem Management psychopharmakainduzierter Sexualstörungen.

  17. Instandhaltung und Normung

    Science.gov (United States)

    Rosenkranz-Wuttig, Angela

    Das DIN Deutsches Institut für Normung e.V. ist ein eingetragener Verein mit Sitz in Berlin. Das DIN erarbeitet gemeinsam mit den Experten der interessierten Kreise Normen und Standards als Dienstleistung für Wirtschaft, Staat und Gesellschaft. Die Kenntnis entsprechender Normen, Standards oder Regeln, sowie deren richtiger Einsatz, ist unter den heutigen Marktbedingungen für jedes Unternehmen ein nicht zu unterschätzender wirtschaftlicher Faktor. Normen schaffen Effizienz bei Produktionsabläufen und sorgen durch eine gleichbleibende sowie vergleichbare Produktqualität für Vertrauen bei den Endverbrauchern. Darüber hinaus stehen Normen unter rechtlichen Aspekten für mehr Sicherheit - Hersteller erreichen bei Anwendung und Einhaltung von Normen ein hohes Maß an rechtlicher Absicherung. Das DIN vertritt die deutschen Interessen in den europäischen und weltweiten Normungsorganisationen, siehe Abb. 1. Zuständig für die elektrotechnische Normung in Deutschland sowie als deutscher Repräsentant in den übernationalen Gremien ist die DKE Deutsche Kommission Elektrotechnik Elektronik Informationstechnik im DIN und VDE.

  18. Quintilian und lateinische Lautlehre

    Directory of Open Access Journals (Sweden)

    Matjaž Babič

    2010-12-01

    Full Text Available Die bekanntesten »grammatischen« Stellen aus Quintilians Institutio oratoria sind I, 4-9 und XII, 10, 27-34. Wie man hat richtig erkannt hat, schenkte er in den Kapiteln über Grammatikunterricht dem sprachlichen Teil verhältnismäßig mehr Aufmerksamkeit  als den literarischen Themen. Dass er den Grammatikunterricht ausführlicher behandelte überrascht nicht, denn Rhetorik als eine kommunikative Tätigkeit kommt ohne Sprachrichtigkeit und Sprachbewußsein nicht aus. Es gibt jedoch auch einige andere Abschnitte behandelnde Stellen, die in den Sonderabhandlungen meist beiseite gelassen werden. Vor allem seine Bemerkungen, die man hie und da im Text findet, sind eine wertvolle Quelle für die Beschreibung des lateinischen Lautsystems. Quintilian erwies als Redner und Rhetoriklehrer für den wirklichen Klang der lateinischen Sprache mehr Feingefühl als Grammmatiker, die die Sprache durch die Brille von elementa sahen und sich dem althergebrachten Normativismus verpflichtet fühlten. Dieses Sprachgefühl ermöglichte es ihm - wenn man die Stellen entsprechend interpretiert - , auch Lautveränderungen wahrzunehmen, die sich seinerzeit noch in den Ansätzen befanden und erst Jahrhunderte später - als sie die phonologische Struktur des Lateinischen beeinflussten - in den Abhandlungen der Grammatiker ihre Kodifizierung fanden.

  19. Apoptose, Inflammation und Angiogenese beim Prostatakarzinom und der benignen Prostatahyperplasie

    OpenAIRE

    Niß-Engel, Wiebke

    2010-01-01

    Sowohl die benigne Prostatahyperplasie (BPH) als auch das Prostatakarzinom (PCA) erlangen als Erkrankungen des Mannes zunehmende Bedeutung. Ziel: Untersuchungsergebnisse zu Markierungsverhalten und Verteilungsmustern verschiedener Proteine bei PCAs und BPHs. Resektate von 50 Patienten wurden immunhistochemisch mit Antikörpern gegen COX2, RANTES, TLR2, BCL2, CASP3 und -9, Fasl, MMP und VEGF gefärbt. Sowohl bei den Markern der Apoptose als auch denen der Inflammation zeigte sich ein...

  20. Applying trait-function relationships for microbial plant decomposition to predict medium longevity in pollution control biofilters.

    Science.gov (United States)

    Oliver, Jason P; Schilling, Jonathan S

    2016-03-01

    Biofilters, bioreactors used for pollution control, can effectively treat a variety of odorous and hazardous emissions, but uncertain medium longevities and associated costs limit biofilter adoption. To improve medium-life estimations for biofilter end-users, litter bags were used to compare decay rates of common biofilter medium types and test the effects of nitrogen (N) enrichment and livestock production emissions on medium decay in a full-scale biofilter over a 27-month period. Generally, "by-product" media (mulch, corn cobs) decayed faster than hardwood media, with decay of softwood media the slowest. Analysis showed nutrient content was the best predictor of early-stage decay, while carbon fractions and nutrient content best predicted medium longevity. N amendments and N-rich barn emissions were found to hasten medium decay. By identifying decay rates and rate predictors specific for biofilter media, we provide biofilter engineers and farmers with a quantitative way to improve medium selection based on the trade-offs between medium cost and replacement frequency.

  1. Mobiler Lernalltag - Erfahrungsbasiert und informell

    NARCIS (Netherlands)

    Specht, Marcus

    2013-01-01

    Specht, M. (2013, 26 April). Mobiler Lernalltag - Erfahrungsbasiert und informell. Invited talk given at the Speedlab Mobile Learning organized by the Kooperative Berlin und Bundeszentrale für politische Bildung, Hannover, Germany.

  2. Kasseler symposium on energy-related system engineering: renewable energy sources and rational energy use. Proceedings '98; Kasseler Symposium Energie-Systemtechnik: Erneuerbare Energien und Rationelle Energieverwendung. Tagungsband '98

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, R. [comp.

    1999-07-01

    The ISET ended the 10th anniversary year since its foundation in 1998 with already the third Kassel symposium on energy-related system engineering: renewable energy sources and rational energy use. Covering several special subjects talks were given about the topics modelling and simulation in the fields of wind energy, photovoltaic systems, hybrid systems or sewage water treatment. The keen interest of the participants shows the importance that modelling of conditions or processes has gained in the meantime in the field of system engineering of renewable energy sources. The core of each simulation is the integration of differential equations, which describe the system. Properties of the system can be easily varied and affects on the overall system can be easily investigated. Critical conditions can be discovered and be taken into consideration at the hardware engineering. Mistakes in terms of component design can be avoided and engineering cost can be reduced considerably. The present conference book gives an ideal overview of the topics discussed during the symposium. (orig.) [German] Sein Jubilaeumsjahr zum zehnjaehrigen Bestehen beschloss das ISET 1998 mit dem nun bereits 3. Kasseler Symposium Energie-Systemtechnik - Erneuerbare Energien und Rationelle Energieverwendung. Fachgebietsuebergreifend wurde zu den Themen Modellbildung und Simulation in Bereichen wie Windenergie, Photovoltaik, Hybridsysteme oder Abwasserbehandlung referiert. Das rege Interesse der Teilnehmer unterstreicht die Bedeutung, die die Modellierung von Zustaenden oder Prozessen in der Systementwicklung bei den erneuerbaren Energien inzwischen gewonnen hat. Der Kern einer jeden Simulation ist die Integration der systembeschreibenden Differentialgleichungen. Eigenschaften des Systems koennen in einfacher Weise variiert und die Auswirkungen auf das Gesamtsystem untersucht werden. Kritische Zustaende koennen entdeckt und in der Entwicklung der Hardware entsprechend beruecksichtigt werden. Fehler

  3. Wasserkraftanlagen Planung, Bau und Betrieb

    CERN Document Server

    Giesecke, Jürgen

    2005-01-01

    Dieses Standardwerk der Wasserkraft liegt hiermit bereits in 4. Auflage vor. Es wurde noch stärker an die Erfordernisse der Praxis angepasst, komplett überarbeitet, aktualisiert und - wo es angebracht war - ergänzt. Wasserkraftanlagen bedeuten Planung, Gestaltung, Ausführung und Betrieb von Bauwerken sowie hydraulischen und elektrischen Komponenten.

  4. Beruf und Alltag alleinlebender Frauen

    Directory of Open Access Journals (Sweden)

    Ellen Seßar-Karpp

    2003-11-01

    Full Text Available Ein Leben ohne Partner und Kinder könnte zu einer Erweiterung des Selbst und damit zu einer positiven Persönlichkeitsveränderung führen. Dieser Hypothese geht U. Schlicht in Interviews mit 15 alleinlebenden Akademikerinnen in Berlin nach und findet ihre Hypothese weitgehend bestätigt.

  5. [Removal characteristics of DCM by biotrickling filter and biofilter].

    Science.gov (United States)

    Pan, Wei-Long; Yu, Jian-Ming; Cheng, Zhuo-Wei; Cai, Wen-Ji

    2013-12-01

    A biofilter (BF) packed with nutrition slow-release material and a biotrickling filter (BTF) packed with ether-based polyurethane foam were set up to remove dichloromethane (DCM) from exhaust gas. Results showed that the biofilm formations in BTF and BF were completed by using the mixture of a special strain and a bacterial community, within 25d and 22d, respectively. Through the observation of the filter surface by SEM, the surface of packings in BF was loose with thin biofilm colonies, whereas the one in BTF was dense with thick biofilm. Under the condition of inlet DCM concentration of 100-1,500 mg x m(-3), EBRT of 25-85 s, the removal efficiency of DCM in BTF was better than that in BF, and the maximum removal load was 22.61 g x (m3 x h)(-1) and 29.05 g (m3 x h)(-1), respectively. The relationship between CO2 production and DCM removal was approximately linear, with the mineralization rate being 70.4% and 66.8% for BTF and BF, respectively. The dynamic behaviors of DCM in BTF and BF were described by the Michaelis-Menten model. Through the calculation, the unit volume maximum degradation rate r(max) was 22.7790 g x (m3 x h)(-1) and 28.5714 g x (m3 x h)(-1), while the gas phase saturation constant Ks was 0.1412 g x m(-3) and 0.1486 g x m(-3)

  6. Macrokinetic determination of isopropanol removal using a downward flow biofilter

    Directory of Open Access Journals (Sweden)

    Vissanu Meeyoo

    2004-02-01

    Full Text Available Biofiltration is a process for eliminating contaminants in air using microorganisms immobilized on a surface of solid support media. This technique has been used successfully to control a number of air contaminants such as odors, Volatile Organic Compounds (VOCs, and Hazardous Air Pollutants (HAPs due to its economic attraction.Microorganisms obtained from local activated sludge (Huay-Kwang wastewater treatment plant (Bangkok, Thailand were selectively enriched and inoculated to the biofilter. The downward flow biofilterwas chosen, due to the ease of water compensation at the dry zone, to operate continuously for more than 3 months under various concentrations of isopropanol alcohol (IPA input at a constant filtered air flow rate of 3 L/min. The maximum IPA elimination capacity of 276 g/m3-h was achieved at the IPA inlet of 342 g/m3-h with acetone production rate of 56 g/m3-h as the intermediate. It was also found that the acetone vapour was partly degraded by the acetone-utilizing microorganisms before leaving the bed. In order to understand the transport phenomena of biofiltration, it is necessary to consider the kinetic behavior of the bioreaction. Therefore, this paper introduces Wani’s method of macrokinetic determination based on the simple Monod kinetic (Wani, Lau and Branion, 1999. In this study, the maximum reaction rate per unit volume (Rm and the Monod constant (KM were found to be 0.12 g/m3 -s and 2.72 g/m3 respectively.

  7. Evaluation on Biofilter in Recirculating Integrated Multi-Trophic Aquaculture

    Directory of Open Access Journals (Sweden)

    S. Sumoharjo

    2013-06-01

    Full Text Available Integrated multi-trophic aquaculture pays more attention as a bio-integrated food production system that serves as a model of sustainable aquaculture, minimizes waste discharge, increases diversity and yields multiple products. The objectives of this research were to analyze the efficiency of total ammonia nitrogen biofiltration and its effect on carrying capacity of fish rearing units. Pilot-scale bioreactor was designed with eight run-raceways (two meters of each that assembled in series. Race 1-3 were used to stock silky worm (Tubifex sp as detrivorous converter, then race 4-8 were used to plant three species of leaf-vegetable as photoautotrophic converters, i.e; spinach (Ipomoea reptana, green mustard (Brassica juncea and basil (Ocimum basilicum. The three plants were placed in randomized block design based on water flow direction. Mass balance of nutrient analysis, was applied to figure out the efficiency of bio-filtration and its effect on carrying capacity of rearing units. The result of the experiment showed that 86.5 % of total ammonia nitrogen removal was achieved in 32 days of culturing period. This efficiency able to support the carrying capacity of the fish tank up to 25.95 kg/lpm with maximum density was 62.69 kg/m3 of fish biomass productionDoi: http://dx.doi.org/10.12777/ijse.4.2.2013.80-85 [How to cite this article: Sumoharjo, S.  and Maidie, A. (2013. Evaluation on Biofilter in Recirculating Integrated Multi-Trophic Aquaculture.  International Journal of  Science and Engineering, 4(2,80-85. Doi: http://dx.doi.org/10.12777/ijse.4.2.2013.80-85

  8. Sukzession und Tradition in Antike und Urchristentum

    Directory of Open Access Journals (Sweden)

    E. Bammel

    1993-01-01

    Full Text Available Succession und tradition in Antiquity and Early Christianity This article focusses on the concepts which today are known as ‘succession’ and ‘apostolic tradition’. It investigates the meaning and reference of these concepts within the context of textual evidences from Antiquity and Early Christianity. From this historical perpective, the article aims at arguing that both concepts should primarily be understood within a judicial and political realm and not merely as theological ideas.

  9. Modelling of the reactive transport of organic pollutants in ground water; Modellierung des reaktiven Transports organischer Schadstoffe im Grundwasser

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, W. [Heidelberg Univ. (Germany). Inst. fuer Umweltphysik

    1999-07-01

    The book describes reactive transport of organic pollutants in ground water and its quantitative monitoring by means of numerical reaction transport models. A brief introduction dealing with the importance of and hazards to ground water and opportunities for making use of ground water models is followed by a more detailed chapter on organic pollutants in ground water. Here the focus is on organochlorine compounds and mineral oil products. Described are propagation mechanisms for these substances in the ground and, especially, their degradability in ground water. A separate chapter is dedicated to possibilities for cleaning up polluted ground water aquifers. The most important decontamination techniques are presented, with special emphasis on in-situ processes with hydraulic components. Moreover, this chapter discusses the self-cleaning capability of aquifers and the benefits of the application of models to ground water cleanup. In the fourth chapter the individual components of reaction transport models are indicated. Here it is, inter alia, differences in the formulation of reaction models as to their complexity, and coupling between suspended matter transport and reaction processes that are dealt with. This chapter ends with a comprehensive survey of literature regarding the application of suspended matter transport models to real ground water accidents. Chapter 5 consists of a description of the capability and principle of function of the reaction transport model TBC (transport biochemism/chemism). This model is used in the two described applications to the reactive transport of organic pollutants in ground water. (orig.) [German] Inhalt des vorliegenden Buches ist die Darstellung des reaktiven Transports organischer Schadstoffe im Grundwasser und dessen quantitative Erfassung mithilfe numerischer Reaktions-Transportmodelle. Auf eine kurze Einleitung zur Bedeutung und Gefaehrdung von Grundwasser und zu den Einsatzmoeglichkeiten von Grundwassermodellen folgt ein

  10. EVALUATION OF BIOAEROSOL EXPOSURES DURING CONDITIONING OF BIOFILTER ORGANIC MEDIA BEDS

    Science.gov (United States)

    Biological media air filters (biofilters) are currently being used for the treatment of inorganic and organic gasses from sewage treatment plants, industrial processes, and remediation systems. The media may be organic material such as comost, wood chips, or synthetic plastic med...

  11. A novel integrated UV-biofilter system to treat high concentration of gaseous chlorobenzene

    Institute of Scientific and Technical Information of China (English)

    WANG Can; XI JinYing; HU HongYing

    2008-01-01

    A novel integrated UV-biofilter system using UV reactor as the pretreatment process was setup to treat high concentration of gaseous volatile organic compounds (VOCs). Another control biofilter without the UV pretreatment was also established to compare the performance of the two systems. Chloro-benzene was selected as a model compound. The two systems were operated in parallel under different the integrated system could eliminate chlorobenzene completely (100% removal efficiency) at the inlet ter. Also the elimination capacity for the organic carbon of the integrated system was much higher than that of the control biofilter. On the basis of intermediates analysis by lon Chromatography and Gas Chromatography-Mass Spectrometry, the UV pretreatment has been proven to be able to enhance the performance of the following biofilter by transferring the recalcitrant target to some more biodegrad-able and soluble organic products (such as formic acid and chlorophenol). Furthermore, the produced ozone, a harmful by-product from UV photo-degradation, could be easily eliminated by the following biofiltration process.

  12. Hexane abatement and spore emission control in a fungal biofilter-photoreactor hybrid unit.

    Science.gov (United States)

    Saucedo-Lucero, J O; Quijano, G; Arriaga, S; Muñoz, R

    2014-07-15

    The performance of a fungal perlite-based biofilter coupled to a post-treatment photoreactor was evaluated over 234 days in terms of n-hexane removal, emission and deactivation of fungal spores. The biofilter and photoreactor were operated at gas residence times of 1.20 and 0.14min, respectively, and a hexane loading rate of 115±5gm(-3)h(-1). Steady n-hexane elimination capacities of 30-40gm(-3)h(-1) were achieved, concomitantly with pollutant mineralization efficiencies of 60-90%. No significant influence of biofilter irrigation frequency or irrigation nitrogen concentration on hexane abatement was recorded. Photolysis did not support an efficient hexane post-treatment likely due to the short EBRT applied in the photoreactor, while overall hexane removal and mineralization enhancements of 25% were recorded when the irradiated photoreactor was packed with ZnO-impregnated perlite. However, a rapid catalyst deactivation was observed, which required a periodic reactivation every 48h. Biofilter irrigation every 3 days supported fungal spore emissions at concentrations ranging from 2.4×10(3) to 9.0×10(4)CFUm(-3). Finally, spore deactivation efficiencies of ≈98% were recorded for the photolytic and photocatalytic post-treatment processes. This study confirmed the potential of photo-assisted post-treatment processes to mitigate the emission of hazardous fungal spores and boost the abatement performance of biotechnologies.

  13. Nutrient removal from separated pig manure digestate liquid using hybrid biofilters.

    Science.gov (United States)

    Zhang, Mingchuan; Lawlor, Peadar G; Hu, Zhenhu; Zhan, Xinmin

    2013-01-01

    In this study, laboratory-scale hybrid biofilters were set up to treat the separated pig manure digestate liquid at two loading rates of 0.12 and 0.07 kg N m(-3) per day. The hybrid biofilters were operated with a sequencing batch reactor mode. Over the operation of 136 days, 84% and 88% of total nitrogen was removed on average in addition with complete nitrification at the high loading rate and low loading rate, respectively. In the anoxic phase, the nitrate reduction rates were 0.31 and 0.24 mg L(-1) min(-1); and in the aerobic phase, nitrification rates were 0.29 and 0.18 mg L(-1) min(-1) at the high loading rate and low loading rate, respectively. It was found that in the hybrid biofilters, biofilm biomass had much higher nitrification and denitrification activities than suspended growth biomass. Phosphorus removals achieved were up to 88%. The results show the hybrid biofilter technology is valid for high nutrient pig manure digestate liquid treatment.

  14. Microbiological and molecular characterization of denitrification in biofilters treating pig manure.

    Science.gov (United States)

    Gilbert, Yan; Le Bihan, Yann; Aubry, Geneviève; Veillette, Marc; Duchaine, Caroline; Lessard, Paul

    2008-07-01

    Aerated organic biofilters treating pig manure exhibit partial nitrogen removal. In order to optimize this process, a better comprehension of its colonization by denitrifiers was needed. Three pilot aerated biofilters, fed with variable Biological Oxygen Demand after five days: Total Kjeldahl Nitrogen (BOD(5):TKN) ratios, were constructed and monitored during 180 days. Nitrogen was analyzed in the gaseous and liquid flows, at different depths in the systems. Denitrifying biomass was characterized by evaluating its observed (nitrogen mass balances) and potential (adapted acetylene inhibition technique) activities and its quantity (real-time PCR on nirS), at different heights inside the biofilters. Denitrification was observed as soon as nitrate was produced by nitrifiers, after approximately 40 days of operation, but the potential to denitrify increased from the beginning of the monitoring period. Biofilter fed with the highest BOD(5):TKN ratio showed significant differences with the others, particularly after 80 days of operation, as its potential activity was lower with a higher observed nitrate removal. Data showed that denitrifiers were mainly localized near the surface of the filter and that a microbiological gradient was present from top to bottom. The potential denitrifying activities were always higher than what was being observed inside the sections studied, suggesting that the biomass could have reduced more nitrate and that conditions found inside the filter did not allow denitrification to completely occur.

  15. Geminicoccus roseus gen. nov., sp. nov., an aerobic phototrophic Alphaproteobacterium isolated from a marine aquaculture biofilter

    DEFF Research Database (Denmark)

    Foesel, Bärbel U.; Gößner, Anita S.; Drake, Harold L.;

    2007-01-01

    A Gram-negative, strictly aerobic, diplococcoid bacterium (strain D2-3T) was isolated from the biofilter of a recirculating marine aquaculture system. Phylogenetic analysis of the 16S rRNA gene sequence of D2-3T indicated that the new organism occupied a novel lineage within the α-1 subclass...

  16. Potential removal of biochemical pollutants in biofilters operating with domestic sewage

    Directory of Open Access Journals (Sweden)

    Maria Regilene de Freitas Costa Paiva

    2011-12-01

    Full Text Available The present study aimed to analyze the removal of Biochemical Oxygen Demand (BOD and Chemical Oxygen Demand (COD in biofilters operating with domestic sewage. Experimental tests were conducted at the Universidade Federal de Viçosa (UFV, Viçosa-MG. The experiment was a split split plot scheme, and in the plots different rates of sewage (0.5, 1.0 and 1.5 m3 m2 d-1 were applied, in the subplot, types of organic material (waste compost, sugar cane bagasse and sawdust were tested and in the subsubplots, five dates of measurements (August, September, October, November and December 2009 were evaluated, in a randomized block with three replications. Samples of domestic sewage were collected upstream and downstream of 27 biofilters for determination of BOD and COD, monthly for five months. The results showed that the effluent from biofilters meets the national standard for release in water streams, with regard to the BOD, after stabilization of the filter elements, and the use of biofilters for the treatment of domestic sewage is a viable technology for small scale because it has low cost, easy operation and good ability to remove biochemical pollutants.

  17. Numerical modeling of nitrogen removal processes in biofilters with simultaneous nitritation and anammox.

    Science.gov (United States)

    Shi, Shun; Tao, Wendong

    2013-01-01

    This study developed a simple numerical model for nitrogen removal in biofilters, which was designed to enhance simultaneous nitritation and anaerobic ammonium oxidation (anammox). It is the first attempt to simulate anammox together with two-step nitrification in natural treatment systems, which may have different kinetic parameters and temperature effects from conventional bioreactors. Prediction accuracy was improved by adjusting kinetic coefficients over the startup period of the biofilters. The maximum rates of nitritation and nitrite oxidation increased linearly over time during the startup period. Simulations confirmed successful enhancement of simultaneous nitritation and anammox (SNA) in the biofilters, with anammox contributing 35% of ammonium removal. Effluent ammonium concentration was affected by influent ammonium concentration and the maximum nitritation rate, and was insensitive to the maximum nitrite oxidation rate and anammox substrate factor. Ammonium removal via SNA was likely limited by biomass of aerobic ammonia oxidizing bacteria in the biofilters. The developed model is a promising tool for studying the dynamics of nitrogen removal processes including SNA in natural treatment systems.

  18. Laboratory study on factors influencing nitrogen removal in marble chip biofilters incorporating nitritation and anammox.

    Science.gov (United States)

    Tao, Wendong; Wen, Jianfeng; Norton, Christopher

    2011-01-01

    It remains challenging to integrate nitritation and anammox in ecologically engineered treatment systems such as passive biofilters that are packed with natural materials and have low energy inputs. This study explored the factors influencing nitritation-anammox through parallel operation of two laboratory-scale biofilters packed with large and small marble chips respectively. Clean marble chips (mainly CaCO3) had an alkalinity dissolution rate of 130 mg CaCO3/kg marble d when water pH approached 6.5. Marble chips effectively increased water pH and provided sufficient alkalinity to support nitritation-anammox in the biofilters. Ammonium and total nitrogen removal decreased by 47 and 26%, respectively, when nutrients were not amended to influent. An influent nitrite concentration above 8.9 mg N/L could inhibit anammox in thin biofilms of biofilters. Nitritation-anammox was enhanced with a hydraulic retention time of 2 d relative to 7 d, likely due to enhanced air entrainment. Size of marble chips rarely made a significant difference in nitrogen removal, possibly due to sufficient surface area available for bacterial attachment and alkalinity dissolution.

  19. Field-scale treatment of landfill gas with a passive methane oxidizing biofilter

    Energy Technology Data Exchange (ETDEWEB)

    Philopoulos, A. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering; Felske, C. [Alberta Research Council, Edmonton, AB (Canada); McCartney, D. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering, Natural Resources Engineering Facility

    2008-09-15

    Municipal solid waste (MSW) landfills produce methane (CH{sub 4}) and carbon dioxide (CO{sub 2}) as a result of the anaerobic biodegradation of organic fractions of waste. This paper provided details of field tests conducted to test 2 approaches that addressed the issue of gases produced at a landfill in Alberta. A CH{sub 4} oxidation layer was applied to replace intermediate and final landfill covers. Landfill gas (LFG) was then trapped using 3 biogenic CH{sub 4} oxidizing biofilters. Mature yard waste was used as a biofilter medium. The LFG was trapped by the liner, accumulated in a collection system, and then passed through the biofilter medium. The study was conducted over a period of 10 months. Results of the study showed that the integration of the biofilter into the landfill cover showed promising results. Low surface emissions were observed in 6 out of 8 monitoring events at 2 of the sites. Low influent LFG fluxes at the third site did not allow for full air sampling analyses to be conducted. 22 refs., 4 tabs., 8 figs.

  20. Bacterial community structure of a full-scale biofilter treating pig house exhaust air

    DEFF Research Database (Denmark)

    Kristiansen, Anja; Pedersen, Kristina Hadulla; Nielsen, Per Halkjær;

    2011-01-01

    Biological air filters represent a promising tool for treating emissions of ammonia and odor from pig facilities. Quantitative fluorescence in situ hybridization (FISH) and 16S rRNA gene sequencing were used to investigate the bacterial community structure and diversity in a full-scale biofilter...

  1. Ammonia biofiltration and community analysis of ammonia-oxidizing bacteria in biofilters.

    Science.gov (United States)

    Jun, Yin; Wenfeng, Xu

    2009-09-01

    Biological removal of ammonia was investigated using compost and sludge as packing materials in laboratory-scale biofilters. The aim of this study is to characterize the composition of ammonia-oxidizing bacteria (AOB) in two biofilters designed to remove ammonia. Experimental tests and measurements included analysis of removal efficiency and metabolic products. The inlet concentration of ammonia applied was 20-100 mg m(-3). Removal efficiencies of BFC and BFS were in the range of 97-99% and 95-99%, respectively. Periodic analysis of the biofilter packing materials showed ammonia was removed from air stream by nitrification and by the improved absorption of NH(3) in the resultant acidity. Nitrate was the dominant product of NH(3) transformation. Changes in the composition of AOB were examined by using nested PCR, denaturing gradient gel electrophoresis (DGGE) and sequencing of DGGE bands. DGGE analysis of biofilter samples revealed that shifts in the community structure of AOB were observed in the experiment; however, the idle phase did not cause the structural shift of AOB. Phylogenetic analysis revealed the population of AOB showed Nitrosospira sp. remains the predominant population in BFC, while Nitrosomonas sp. is the predominant population in BFS.

  2. [Effect of hydraulic load distribution on sewage treatment efficiency of earthworm bio-filter].

    Science.gov (United States)

    Yang, Jian; Yang, Jian; Yang, Ju-Chuan; Chen, Qiao-Yan; Lou, Shan-Jie

    2008-07-01

    Effect of hydraulic load distribution on sewage treatment efficiency of earthworm bio-filter was studied by analyzing influent and effluent of earthworm bio-filter and earthworm behaviors. The results show that when hydraulic load varying from 2.0 m3/(m2 x d) to 6.0 m3/(m2 x d), the concentration of each pollutant in earthworm bio-filter effluent increases slowly and is little effected by hydraulic load. When hydraulic load reaches 6.7 m3/(m2 x d), the concentration of COD, BOD5, SS, NH4(+) -N and TP in earthworm bio-filter effluent increases obviously, but the TN concentration in effluent presents descending tendency. The earthworms become rather inadaptable to the living conditions at this operating mode. As hydraulic load increasing, the earthworms' relative ingestive ability is improved at first, and then decreases. The earthworms' relative ingestive ability comes to the maximum at hydraulic load of 4.8 m3/(m2 x d), with good organic removal efficiency. The relation ships between hydraulic load and average weight, average density, unit-area biomass of the earthworms are significant negative correlation. The hydraulic load of 4.8 m3/(m2 x d) is recommended, but not over 6.7 m3/(m2 x d).

  3. Potential application of an Aspergillus strain in a pilot biofilter for benzene biodegradation

    Science.gov (United States)

    Sun, Da; Zhang, Kun; Duan, Chuanren; Wu, Wei; Deng, Daiyong; Yu, Donghong; Shahzad, M. Babar; Xu, Dake; Tang, Ju; Luo, Li; Chen, Jia; Wang, Jinxuan; Chen, Yidan; Xie, Xiang; Wang, Guixue

    2017-01-01

    A biofilter with fungus was developed for efficient degradation of benzene, which can overcome the potential risk of leakage commonly found in such services. Results indicated that the optimum parameter values were temperature 40 °C, pH 6, and 500 mg L−1 of the initial benzene concentration. Besides, the empty bed residence time and inlet load range of biofilter were set to 20 s and 21.23–169.84 g m−3 h−1 respectively. Under these conditions, this biofilter can obtain the maximum removal efficiency of more than 90%, the eliminating capacity could be up to 151.67 g m−3 h−1. Furthermore, scanning electron microscopy was used to investigate three filler materials for packing fungus biofilm. This is the first study introducing an Aspergillus strain for benzene removal and these results highlight that the development of this biofilter has the potential scaling-up application as gas-processing of industrial wastes. PMID:28383064

  4. Investigation into the aerodynamic processes of air treatment using a plate-type biofilter.

    Science.gov (United States)

    Baltrėnas, Pranas; Kleiza, Jonas; Idzelis, Raimondas Leopoldas

    2016-01-01

    The research conducted has involved a laboratory stand of a plate-type air treatment biofilter with a capillary system for humidifying packing material composed of polymer plates vertically arranged next to each other and producing a capillary effect of humidification. The pattern of arranging the plates has sufficiently large spaces (6 mm), and therefore the use of the plate-type structure decreases the aerodynamic resistance of the device. Slightly pressed slabs attached on both sides of the plates are made of heat-treated wood fibre, to increase the longevity of which, wood waste has been heat-treated in the steam explosion reactor under the pressure of 32 bars and a temperature of 235 °C. This is the method for changing the molecular structure of wood, which stops the decay of wood fibre in a humid environment and thus increases the life span of biofilter plates. The research performed has disclosed that, under the application of the above introduced structure of the biofilter, the aerodynamic resistance of the biofilter reaches 1 ÷ 5 Pa when the rate of the air flow passing through the device makes 0.08 m/s. For evaluating the reliability of the obtained results, the theoretical model has been applied.

  5. Investigation of factors on a fungal biofilter to treat waste gas with ethyl mercaptan

    Institute of Scientific and Technical Information of China (English)

    ZHU Guo-ying; LIU Jun-xin

    2004-01-01

    The biofilter is cost-effective for the waste gases treatment. The bacterial is the main microorganism in the conventional biofilters. However, it faces some problems on the elimination of hydrophobic compounds. In order to overcome these problems, the biofilters with fungi were developed. The objective of this study is to investigate the factors affecting ethyl mercaptan(EM)-degradation using a fungal biofilter. A laboratory experiment was set up. The effects of loading rate, empty bed residence times(EBRT) and pH on EM degradation were investigated. Over 95% removals of EM could be achieved, under the condition of the influent loadings below 50 g/(m·h). Removal efficiencies improved to 98% with EM loading decreased to 45 g/(m·h). For long EBRT of 58 s corresponding to a flow rate of 0.3 m3/h, the EM removal efficiencies of over 98% were observed. However, when EBRT was decreased to 14 s, the removal efficiencies fell under 80%. The pH range of 3-5 was feasible to fungi.

  6. Influence of synthetic packing materials on the gas dispersion and biodegradation kinetics in fungal air biofilters

    NARCIS (Netherlands)

    Prenafeta-Boldú, F.X.; Illa, J.; Groenestijn, J.W. van; Flotats, X.

    2008-01-01

    The biodegradation of toluene was studied in two lab-scale air biofilters operated in parallel, packed respectively with perlite granules (PEG) and polyurethane foam cubes (PUC) and inoculated with the same toluene-degrading fungus. Differences on the material pore size, from micrometres in PEG to m

  7. Fluidization velocity assessment of commercially available sulfur particles for use in autotrophic denitrification biofilters

    Science.gov (United States)

    There has been no evaluation of sulfur-based autotrophic denitrification using fluidized biofilters in a recirculating aquaculture system to mitigate nitrate-nitrogen loads. The objectives of this work were to quantify the particle size distribution, specific surface area, and fluidization velocitie...

  8. Air purification from TCE and PCE contamination in a hybrid bioreactors and biofilter integrated system.

    Science.gov (United States)

    Tabernacka, Agnieszka; Zborowska, Ewa; Lebkowska, Maria; Borawski, Maciej

    2014-01-15

    A two-stage waste air treatment system, consisting of hybrid bioreactors (modified bioscrubbers) and a biofilter, was used to treat waste air containing chlorinated ethenes - trichloroethylene (TCE) and tetrachloroethylene (PCE). The bioreactor was operated with loadings in the range 0.46-5.50gm(-3)h(-1) for TCE and 2.16-9.02gm(-3)h(-1) for PCE. The biofilter loadings were in the range 0.1-0.97gm(-3)h(-1) for TCE and 0.2-2.12gm(-3)h(-1) for PCE. Under low pollutant loadings, the efficiency of TCE elimination was 23-25% in the bioreactor and 54-70% in the biofilter. The efficiency of PCE elimination was 44-60% in the bioreactor and 50-75% in the biofilter. The best results for the bioreactor were observed one week after the pollutant loading was increased. However, the process did not stabilize. In the next seven days contaminant removal efficiency, enzymatic activity and biomass content were all diminished.

  9. Bewußtseins- und Organisationsentwicklung - Rationale und nichtrationale Grundlagen, Konzepte und Realitäten

    OpenAIRE

    Epstein, Holger

    2008-01-01

    Die aktuellen Krisen der menschlichen Lebenswelten und von Mutter Erde zeigen die Dringlichkeit eines grundlegenden Wandels der Art, wie wir über Wirtschaft, Organisationen und Wissenschaft denken und wie wir mit diesem Denken unser Handeln gestalten. Die wissenschaftlichen und organisationalen Revolutionen, an deren Wiege herausragende Persönlichkeiten wie Newton, Descartes, Kopernikus, Adam Smith, Calvin, Frederick W. Taylor ... stehen, bilden nun aus ihrem Schatten heraus zunehmend existen...

  10. Altautoverwertung zwischen Staat und Markt: Bedingungen und Potentiale zur Modernisierung von Lagerhaltung und Marketing gebrauchter Autoteile

    OpenAIRE

    Lucas, Rainer

    2000-01-01

    Das Arbeitspapier diskutiert vor dem Hintergrund veränderter gesetzlicher Rahmen-und Wettbewerbsbedingungen in der Autoverwertung Ziele und Maßnahmen zurStärkung kleiner und mittelständischer Verwertungsbetriebe. Der Bereich GebrauchteAutoteile wird im Rahmen eines regionalen Fallbeispiels einer tiefergehenden Analyseunterzogen. Hieraus werden Vorschläge zur regionalen Netzwerkbildung innerhalb derBranche und neue Dienstleistungsperspektiven abgeleitet. Ein wesentliches Koope-rationsfeld ist ...

  11. Design and analysis of high-numerical-aperture beam shaping systems; Design und Analyse von Strahlformungssystemen hoher numerischer Apertur

    Energy Technology Data Exchange (ETDEWEB)

    Schweitzer, Hagen

    2009-11-24

    The generation of light tailored to measure stands today in the center of many innovative applications. A possibility of the flexible manipulation of light is the laser-beam shaping.Aim is thereby to transform the intensity profile of a laser beam to a wanted profile. The main topic of this thesis is the modeling and propagation of laser light in paraxial and non-paraxial beam-shaping systems as well as the optimization of these systems by means of a generalized projection algorithm. This algorithm is applied for the optimization by means of aspherical formula or polynomials point-by-point parametrized beam shaping surfaces. It is shown that during the optimization a regardment of diffraction, interference, and abberations is possible. The latter can not only be regarded, but directly used for the beam shaping. Finally it is shown that the aberrations of spherical catalogue lenses are already sufficient for some beam-shaping applications. The efficiency of the developed optimization algorithms is demonstrated both on paraxial and on non-paraxial beam-shaping examples with a numerical aperture of up to 0.62. Finally in the present thesis concepts for the achromatization and for the wave-length multiplexing are introduced, which are based on the application of diverse surfaces and materials with different dispersion. While the achromatization aims to make the optical function of a beam-shaping system wave-length independent, the wavelength multiplexing tries directly to realize different optical functions for diverse design wavelengths. [German] Die Erzeugung massgeschneiderten Lichts steht heute im Mittelpunkt vieler innovativer Anwendungen. Eine Moeglichkeit der flexiblen Manipulation von Licht ist die Laserstrahlformung. Ziel ist es dabei, das Intensitaetsprofil eines Laserstrahls in ein gewuenschtes Profil umzuformen. Schwerpunkt dieser Arbeit ist die Modellierung und Ausbreitung von Laserlicht in paraxialen und nicht-paraxialen Strahlformungssystemen sowie die

  12. Hexane abatement and spore emission control in a fungal biofilter-photoreactor hybrid unit

    Energy Technology Data Exchange (ETDEWEB)

    Saucedo-Lucero, J.O. [Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid (Spain); IPICyT, Instituto Potosino de Investigación Científica y Tecnológica, División de Ciencias Ambientales, Camino a la Presa San José No. 2055, C.P., 78216 San Luis Potosí (Mexico); Quijano, G. [Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid (Spain); Arriaga, S. [IPICyT, Instituto Potosino de Investigación Científica y Tecnológica, División de Ciencias Ambientales, Camino a la Presa San José No. 2055, C.P., 78216 San Luis Potosí (Mexico); Muñoz, R., E-mail: mutora@iq.uva.es [Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid (Spain)

    2014-07-15

    Highlights: • A fungal biofilter/photoreactor was evaluated in terms of hexane and spore removal. • Biofilter supported elimination capacities of ≈35 g m{sup −3} h{sup −1} and CO{sub 2} yields of ≈75%. • The photocatalytic process slightly boosted the hexane abatement performance. • Biofilter emitted fungal spores at concentrations of 2.4 × 10{sup 3}–9.0 × 10{sup 4} CFU m{sup −3}. • Photo-assisted post-treatments resulted in spore deactivation efficiencies of 98%. - Abstract: The performance of a fungal perlite-based biofilter coupled to a post-treatment photoreactor was evaluated over 234 days in terms of n-hexane removal, emission and deactivation of fungal spores. The biofilter and photoreactor were operated at gas residence times of 1.20 and 0.14 min, respectively, and a hexane loading rate of 115 ± 5 g m{sup −3} h{sup −1}. Steady n-hexane elimination capacities of 30–40 g m{sup −3} h{sup −1} were achieved, concomitantly with pollutant mineralization efficiencies of 60–90%. No significant influence of biofilter irrigation frequency or irrigation nitrogen concentration on hexane abatement was recorded. Photolysis did not support an efficient hexane post-treatment likely due to the short EBRT applied in the photoreactor, while overall hexane removal and mineralization enhancements of 25% were recorded when the irradiated photoreactor was packed with ZnO-impregnated perlite. However, a rapid catalyst deactivation was observed, which required a periodic reactivation every 48 h. Biofilter irrigation every 3 days supported fungal spore emissions at concentrations ranging from 2.4 × 10{sup 3} to 9.0 × 10{sup 4} CFU m{sup −3}. Finally, spore deactivation efficiencies of ≈98% were recorded for the photolytic and photocatalytic post-treatment processes. This study confirmed the potential of photo-assisted post-treatment processes to mitigate the emission of hazardous fungal spores and boost the abatement performance of

  13. Konservative und operative Therapie bei Harninkontinenz, Deszensus und Urogenitalbschwerden

    Directory of Open Access Journals (Sweden)

    Eberhard J

    2000-01-01

    Full Text Available Urogynäkologische Beschwerden wie Harninkontinenz, Infektionen, vulvo-vaginale und vesikale Reizzustände, Juckreiz, Dyspareunie, Beckenbodenschwäche, Deszensusbeschwerden werden in irgendeiner Form bei fast jeder Frau im Laufe ihres Lebens zur behandlungsbedürftigen Krankheit. Die Ursachen dieser häufigsten Frauenleiden sind vielfältig. Eine erfolgreiche Therapie sollte auf der Polyätiologie urogynäkologischer Krankheiten aufbauen und die verschiedenen Therapiemöglichkeiten zu einem patienten- und krankheitsadaptierten Behandlungskonzept zusammenfügen. Die Bausteine der konservativen Therapie sind: Trink- und Miktionstraining, Physiotherapie mit den Hilfsmitteln Kugeln, Kegel, Elektrostimulation und Biofeedbackmethoden; Östrogene, Pessare, Infekttherapie, Intimpflege, blasenrelaxierende und andere urogynäkologische Medikamente. Der Einsatz dieser Therapiebausteine wird ausführlich besprochen. Auch wird gezeigt, wann und wie operiert werden soll, wenn die konservative Therapie nicht zum Ziel führt.

  14. Karamell und Schokolade optimal

    Science.gov (United States)

    Eichhorn, Andreas

    In verschiedenen Situationen in Technik, Wirtschaft oder Politik ist man daran interessiert unter einer Anzahl von möglichen Entscheidungen die jeweils beste auszuwählen, also die optimale Entscheidung zu treffen, die den größtmöglichen Nutzen bringt. In den meisten Fällen sind Nutzen und Entscheidungsalternativen nicht exakt gegeben, Entscheidungen werden dann entweder sprachlichargumentativ ausgewählt und begründet oder gar aus dem Bauch heraus gefällt. In manchen Fällen ist es aber möglich, Entscheidungsalternativen und Nutzen in Zahlen und Formeln so auszudrücken, dass über diese Beschreibung im Prinzip die optimalen Entscheidungen und der maximale Nutzen festgelegt sind. Dabei ist zu beachten, dass bei mehreren (gleichzeitig oder hintereinander) zu treffenden Entscheidungen gewisse Abhängigkeiten zu berücksichtigen sind, bezüglich der möglichen Alternativen. Wenn beispielsweise die Umsetzung einer bestimmten (Teil-)Entscheidung mit bestimmten Kosten verbunden wäre, so stünde dieser Geldbetrag für andere Entscheidungen nicht mehr zur Verfügung.

  15. Rosetta und Yella

    Directory of Open Access Journals (Sweden)

    Urs Urban

    2009-11-01

    Full Text Available L’apparition de l’homo oeconomicus marque la fin des grands récits et par là de l’ensemble social que ceux-ci avaient légitimé. En même temps cependant il entre dans les récits littéraires – et filmiques, par exemple dans Rosetta (1999 des frères Dardenne et Yella (2007 de Christian Petzold. L’article se propose de montrer comment ces derniers réussissent à mettre en scène les apories existentielles d’un sujet produit par le dispositif économique en appliquant des procédés narratifs permettant de problématiser la narration elle-même.Mit dem Auftauchen des homo oeconomicus scheint das Ende der großen Erzählungen und des von diesen legitimierten sozialen Zusammenhangs besiegelt. Genau in diesem Moment indes beginnen sich die kleinen, die literarischen und filmischen Erzählformen für den ökonomischen Menschen zu interessieren. In dem Artikel geht es darum zu zeigen, wie die Brüder Dardenne und Christian Petzold die Aporien eines vom ökonomischen Dispositiv produzierten Subjekts in ihren Filmen Rosetta (1999 und Yella (2007 erzählerisch umsetzen und dabei genau diese erzählerische Umsetzbarkeit in Frage stellen.

  16. Patentierung und Patentlage

    Science.gov (United States)

    Herrmann, Uwe

    Gewerbliche Schutzrechte nehmen in der nationalen Rechts- und Wirtschaftsordnung sowie auch auf internationaler Ebene stetig an Bedeutung zu. Sie dienen dem Schutz geistigen Eigentums und sind für jeden Gewerbetreibenden nicht nur im Hinblick darauf von Bedeutung, eigene Rechte zu sichern, sondern auch insofern von Relevanz, dass ein Verstoß gegen Rechte Dritter zu vermeiden ist. Zu den gewerblichen Schutzrechten gehören unter anderem Kennzeichenrechte, Geschmacksmusterrechte sowie die sogenannten technischen Schutzrechte in Form des Patents sowie des Gebrauchsmusters. Die folgenden Ausführungen befassen sich ausschließlich mit den technischen Schutzrechten und geben eine kurze Einführung in die Voraussetzungen, das Entstehen und den Wegfall sowie in die Wirkungen technischer Schutzrechte. Beleuchtet wird die Situation im Wesentlichen im Hinblick auf nationale technische Schutzrechte, d. h. auf Deutsche Patente und Gebrauchsmuster sowie auf Europäische Patente, die Schutz in Deutschland entfalten. Die Möglichkeit der Erlangung von Schutzrechten im außereuropäischen Ausland wird nur am Rande gestreift.

  17. Epilepsie und polyzystisches Ovarialsyndrom

    Directory of Open Access Journals (Sweden)

    Rösing B

    2012-01-01

    Full Text Available Epilepsien sind gehäuft mit endokrinen Funktionsstörungen vergesellschaftet. Bei Frauen gehören Zyklusstörungen, Hyperandrogenismus, Gewichtszunahme und Subfertilität dazu. Die vorliegende Übersicht zeigt aktuelle Daten und pathophysiologische Vorstellungen zum Zusammenhang zwischen einer Erkrankung mit Epilepsie, ihrer Therapie, dem polyzstischen Ovarialsyndrom (PCOS, sowie assoziierten metabolischen Abweichungen. Mögliche Ursachen für das Auftreten endokriner Störungen bei Epilepsie sind (1. der direkte Einfluss temporal gelegener epileptogener Läsionen oder der antiepileptischen Medikamente (AED auf die hypothalamisch-hypophysär gonadale Achse (HHG, (2. der Einfluss von AED auf die ovarielle Funktion, (3. der Einfluss der AED auf den Steroidhormonmetabolismus inklusive ihrer Serumeiweißbindung und (4. AED-bedingte sekundäre endokrine Störungen durch Gewichtszunahme und veränderten Insulinmetabolismus. Die regelmäßige ärztliche Kontrolle klinischer endokriner Parameter wie Gewichtsentwicklung, Regeltempostörungen und Hirsutismus ist bei Frauen mit Epilepsie obligat. Einzelne auffällige Laborparameter (z. B. sinkendes sexualhormonbindendes Globulin [SHBG], ansteigende Testosteronwerte, Dysbalance der Gonadotropine luteinisierendes Hormon zu follikelstimulierendem Hormon (LH/FSH oder bildgebende Befunde (polyzystische Ovarien ohne klinisches Korrelat sollten engmaschig, zunächst 1–3-monatlich kontrolliert werden, um entstehende Endokrinopathien frühzeitig behandeln zu können.

  18. Supraleitung Grundlagen und Anwendungen

    CERN Document Server

    Buckel, Werner

    2013-01-01

    Grundlegende Konzepte und Eigenschaften von Supraleitern, die Herstellung und Entwicklung von neuen supraleitenden Materialien sowie moderne Anwendungsbereiche sind die Schwerpunktthemen des Buches. Das größte Potential zur Nutzung der Supraleitung liegt in der Energietechnik. Fast unbemerkt trägt die Einführung von Kabeln, Magneten, Transformatoren oder Lagern aus supraleitenden Materialien bei zur Effizienzsteigerung bei der Stromübertragung oder in Motoren. Durch seiner klare Sprache und zahlreiche erläuternde Abbildungen eignet sich der Band hervorragend als einführendes Lehrbuch. Der Schwierigkeitsgrad wird von Kapitel zu Kapitel gesteigert. So können auch Einsteiger ohne einschlägige Vorkenntnisse dem Stoff folgen. Dank der über 350 Literaturhinweise bekommt der Leser außerdem einen Überblick über die wichtigsten Publikationen zum Thema. Ein unverzichtbares Lehrbuch also für Physik-Studenten und Studierende der Ingenieurwissenschaften. Fachleuten in Forschung und Praxis leistet das Buch au...

  19. Investigating bacterial populations in styrene-degrading biofilters by 16S rDNA tag pyrosequencing.

    Science.gov (United States)

    Portune, Kevin J; Pérez, M Carmen; Álvarez-Hornos, F Javier; Gabaldón, Carmen

    2015-01-01

    Microbial biofilms are essential components in the elimination of pollutants within biofilters, yet still little is known regarding the complex relationships between microbial community structure and biodegradation function within these engineered ecosystems. To further explore this relationship, 16S rDNA tag pyrosequencing was applied to samples taken at four time points from a styrene-degrading biofilter undergoing variable operating conditions. Changes in microbial structure were observed between different stages of biofilter operation, and the level of styrene concentration was revealed to be a critical factor affecting these changes. Bacterial genera Azoarcus and Pseudomonas were among the dominant classified genera in the biofilter. Canonical correspondence analysis (CCA) and correlation analysis revealed that the genera Brevundimonas, Hydrogenophaga, and Achromobacter may play important roles in styrene degradation under increasing styrene concentrations. No significant correlations (P > 0.05) could be detected between biofilter operational/functional parameters and biodiversity measurements, although biological heterogeneity within biofilms and/or technical variability within pyrosequencing may have considerably affected these results. Percentages of selected bacterial taxonomic groups detected by fluorescence in situ hybridization (FISH) were compared to results from pyrosequencing in order to assess the effectiveness and limitations of each method for identifying each microbial taxon. Comparison of results revealed discrepancies between the two methods in the detected percentages of numerous taxonomic groups. Biases and technical limitations of both FISH and pyrosequencing, such as the binding of FISH probes to non-target microbial groups and lack of classification of sequences for defined taxonomic groups from pyrosequencing, may partially explain some differences between the two methods.

  20. The effects of methanol on the biofiltration of dimethyl sulfide in inorganic biofilters.

    Science.gov (United States)

    Zhang, Yuefeng; Liss, Steven N; Allen, D Grant

    2006-11-01

    Air emissions from the pulp and paper industry frequently contain reduced sulfur compounds (RSC), such as dimethyl sulfide (DMS) mixed with volatile organic compounds (VOC) (e.g., methanol, MeOH) and it is desirable to treat either one or both of these groups of compounds. The objective of this study was to assess the effects of VOC (MeOH) on the biofiltration of DMS. Results obtained from continuous experiments using three bench-scale biofilters packed with inorganic material clearly show that MeOH has a positive effect (11-fold increase) on the biofiltration of DMS. Further experiments indicate that MeOH addition enhances biomass concentration and viability (threefold) in the biofilters. However, a suspension of MeOH addition causes a rapid significant increase (twofold) in the removal rate of DMS, suggesting that the presence of MeOH also has a competitive effect on DMS biodegradation. This negative effect was also confirmed in batch experiments. The decrease of biofilter performance with time for a long-term suspension of MeOH addition indicates that MeOH addition is necessary to sustain a high removal rate of DMS in inorganic biofilters. Results on metabolic products of DMS biodegradation demonstrate that DMS is almost completely converted to sulfate in the absence of MeOH, while it is partially oxidized to elemental sulfur in the presence of MeOH. This study suggests that there exists an optimum mix of DMS and MeOH for the treatment of DMS emissions in inorganic biofilters.

  1. The use of novel packing material for improving methane oxidation in biofilters.

    Science.gov (United States)

    Brandt, Emanuel Manfred F; Duarte, Felipe V; Vieira, João Paulo R; Melo, Vinícius M; Souza, Cláudio L; Araújo, Juliana C; Chernicharo, Carlos Augusto L

    2016-11-01

    The use of biofilters (working bed volume of 7.85 L) for the oxidation of CH4 at low concentrations (from 0.17%v/v to 3.63%v/v, typically in waste gas from anaerobic sewage treatment) was investigated and four empty bed residence times were tested (in min): 42.8, 29.5, 19.6, and 7.4. Mixtures of organic (composted leaves) and three non-organic materials (sponge-based material - SBM, blast furnace slag - BFS, and expanded vermiculite - ExpV) were used as packing media. Along 188 operational days after the steady state was reached (95 days for start-up), the CH4 mineralization decreased while the inlet loads gradually increased from 3.0 ± 0.8 gCH4 m(-3) h(-1) to 148.8 ± 4.4 gCH4 m(-3) h(-1). The biofilter packed with ExpV showed the best results, since the CH4 conversions decreased from 95.0 ± 5.0% to 12.7 ± 3.7% as a function of inlet concentration, compared to the other two biofilters (SBM and BFS) which showed CH4 conversions decreasing from 56.0 ± 5.4% to 3.5 ± 1.2% as a function of inlet concentration. The methanotrophic activity of biomass taken from ExpV biofilter was three times higher than the activity of biomass from the other two biofilters. Taken together, these results suggested that ExpV provides an attractive environment for microbial growth, besides the mechanical resistance provided to the whole packing media, showing the potential to its use in biofiltration of diffuse CH4 emissions.

  2. Modelling of carbonisation of renewable fuels in a rotary kiln reactor; Modellierung der Karbonisierung nachwachsender Rohstoffe im Drehrohrreaktor

    Energy Technology Data Exchange (ETDEWEB)

    Klose, W.; Schinkel, A.P. [Univ. Kassel (Germany). Inst. fuer Thermische Energietechnik

    1998-09-01

    The contribution models the pyrolysis of corn in a rotary kiln reactor. The model comprises a solution of the two-dimensional energy and mass balances for the solid phase. The movement of the solid matter inside the reactor is described by model equations. The influence of various operating parameters on the pyrolysis process is discussed, i.e. temperature, rotational speed, length and angle of inclination of the tube. (orig.) [Deutsch] In diesem Beitrag wird die Pyrolyse von Mais im Drehrohrreaktor modelliert. Das Modell beinhaltet die Loesung der 2dimensionalen Energie- und Stoffbilanzen fuer die feste Phase. Die Gutbewegung im Drehrohr wird mit Hilfe von Modellansaetzen beschrieben. Es wird der Einfluss der Betriebsparameter Temperatur, Drehzahl, Laenge und Neigungswinkel des Rohres auf die Pyrolyse diskutiert. (orig.)

  3. Defect size dependent contrast reduction and additional blurring from scattered radiation reduce the quality of radiological images. A comparison of films and digital detectors; Fehlergroessenabhaengige Kontrastreduktion und zusaetzliche Unschaerfe durch Streustrahlung reduzieren die Bildqualitaet radiologischer Abbildungen. Film und digitale Detektoren im Vergleich

    Energy Technology Data Exchange (ETDEWEB)

    Ewert, Uwe; Beckmann, Joerg; Bellon, Carsten; Jaenisch, Gerd-Ruediger; Zscherpel, Uwe; Jechow, Mirko [Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin (Germany); Grosser, Anja [Technische Fachhochschule Wildau (Germany)

    2008-07-01

    Definition haengt von Kontrast, Rauschen (beim Film: Koernigkeit als Aequivalent zum Bildrauschen) und Unschaerfe ab. Diese Parameter werden normalerweise mit Bildguetepruefkoerpern (BPK) gemessen. Die Streustrahlung reduziert im Allgemeinen immer die Bildquali-taet in der Radiographie. Die verschiedenen Einflussgroessen werden analysiert und es werden dabei die verschiedenen Techniken wie Film-Radiographie, Computer-Radiographie mit Speicherfolien und digitale Radiographie mit Matrixdetektoren (englisch: digital detector arrays - DDA) beruecksichtigt. In Lehrbuechern und Standards (z.B. ASTM E 1000) werden das Streuverhaeltnis k und verschiedene Kontras-te definiert. Es handelt sich hierbei z.B. beim radiographischen Kontrast um den spezifischen Kontrast und den relativen Kontrast. Fuer digitale Medien werden zu-saetzliche Parameter wie das Signal-Rausch-Verhaeltnis SNR und das Kontrast-Rausch-Verhaeltnis CNR eingefuehrt, wobei das inverse CNR der bekannten Kontrastempfindlichkeit entspricht, die typischerweise mit den BPKs gemessen wird. Es werden auch im Rahmen des Projektes ''FilmFree'' die optimalen Bedingungen fuer den Filmersatz untersucht. In diesem Zusammenhang wird der Einfluss der Streu-strahlung aus dem Messobjekt und dem Detektor bestehend aus Kassette bzw. Ge-haeuse und sensitiver Detektorschicht auf die Bildqualitaet ermittelt. Die numerische Modellierung (Monte-Carlo-Technik) wird eingesetzt, um die Streustrahlung und die Primaerstrahlung aus dem Objekt separat zu bestimmen. Die Streustrahlung aus dem Objekt und Detektor erzeugen eine Abbildung des Objektes, die dem Primaerstrahlungsbild ueberlagert ist, wobei das Streubild eine hoehere Unschaerfe aufweist. Dieser Effekt tritt bevorzugt bei hoeheren Strahlenergien auf. Die Streubilder weisen Unschaerfen im cm-Bereich auf. Dieser Effekt wirkt sich sowohl bei der klassischen Filmradiographie als auch besonders bei der digitalen Radiographie und Computer-tomographie stoerend aus. Weiterhin

  4. Die biene und ihre produkte in der kunst und im alltagsleben (Fruhchristliche und byzantinische Zeit

    Directory of Open Access Journals (Sweden)

    Liveri Angeliki

    2010-01-01

    Full Text Available Die vorliegende Arbeit ist in zwei Teile geteilt: den kunst- und kulturhistorischen Teil. Im ersten Teil werden Darstellungen uber Bienen Bienenzucht, Honig und Wachs seit der fruhchristlichen bis zur spatbyzantinischen Zeit vorgefuhrt. Daher ist es als Beitrag in der "Ikonographie" der Biene wahrend dieser Zeit zu verstehen. Im kulturhistorischen Teil werden Informationen uber die Bienenzucht, den Handel mit Honig und Wachs sowie ihre vielfaltige Anwendung von der byzantinischen Gesellschaft an Hand der primaren Quellen, des Standes der Forschung und der archaologischen Funden erwahnt. Damit ist erwunscht ein moglichst gutes Bild der byzantinischen Bienenzucht wieder zu geben und die Nutzung der Bienenprodukte in Byzanz anschaulich zu machen.

  5. Reuchlin und die Kabbala

    OpenAIRE

    2008-01-01

    Auszug: Hundert Jahre nachdem Johannes Reuchlin sein wissenschaftliches Werk vollendet hatte, war der von ihm hinterlassene Eindruck auf die europäische Wissenschaft und das europäische Denken so nachdrücklich, daß er - liebe- oder vorwurfsvoll - einmal >Rabbi Capnion< genannt wurde. Und wirklich - so meint Joseph Blau in seiner Darstellung der christlichen Kabbala - habe Reuchlin der hebräischen Literatur mehr gedient als mancher ordentliche Rabbiner. Ähnlich hat Gershom Scholem, der Begründ...

  6. Fungal biofilters for toluene biofiltration: evaluation of the performance with four packing materials under different operating conditions.

    Science.gov (United States)

    Maestre, Juan P; Gamisans, Xavier; Gabriel, David; Lafuente, Javier

    2007-03-01

    Packing materials play a key role in the performance of bioreactors for waste gas treatment and particularly in biofilter applications. In this work, the performance of four differently packed biofilters operated in parallel for the treatment of relatively high inlet concentration of toluene was studied. The reactors were compared for determining the suitability of coconut fiber, digested sludge compost from a waste water treatment plant, peat and pine leaves as packing materials for biofiltration of toluene. A deep characterisation of materials was carried out. Biological activity and packing capabilities related to toluene removal were determined throughout 240 days of operation under different conditions of nutrients addition and watering regime. Also, biofilters recovering after a short shutdown was investigated. Nutrient addition resulted in improved removal efficiencies (RE) and elimination capacities (EC) of biofilters reaching maximum ECs between 75 and 95 g m(-3)h(-1) of toluene. In the first 80 days, the pH decreased progressively within the reactors, causing a population change from bacteria to fungi, which were the predominant decontaminant microorganisms thereafter. All reactors were found to recover the RE rapidly after a 5 days shutdown and, in a maximum of 7 days, all reactors had been completely recuperated. These results point out that fungal biofilters are a suitable choice to treat high loads of toluene. In general, coconut fiber and compost biofilters exhibited a better performance in terms of elimination capacity and long-term stability.

  7. Nutzerorientiertes Management von materiellen und immateriellen Informationsobjekten

    OpenAIRE

    Hübsch, Chris

    2001-01-01

    Schaffung einer stabilen, erweiterbaren und skalierbaren Infrastruktur für die Bereitstellung von Diensten im Umfeld von Bibliotheken und ähnlichen wissensanbietenden Einrichtungen unter Verwendung von XML-RPC und Python.

  8. Editorial: Medien und soziokulturelle Unterschiede

    Directory of Open Access Journals (Sweden)

    Horst Niesyto

    2009-09-01

    Full Text Available Kinder, Jugendliche und Erwachsene nutzen Medien in sehr unterschiedlicher Weise. Insbesondere handlungstheoretische Ansätze der Medienforschung konnten überzeugend belegen, dass Menschen keine passive Zielscheibe von Medien sind, sondern diese aktiv nutzen. Medienrezeption und Medienaneignung wird als Teil sozialen Handelns verstanden, die Mediennutzung wird im Lebenskontext der Menschen verortet, es wird nach der Bedeutung der Medien im Alltag und für die Lebensbewältigung gefragt. Kulturtheoretisch motivierte Studien, die die Eigenleistungen der Individuen im Auswahlprozess und in der Konstruktion von Bedeutungen betonen, verdeutlichten eigensinnige Prozesse der Medienaneignung und eine Vielfalt medienkultureller Orientierungen. Im Bereich des Lernens mit Medien wurden die Chancen selbstgesteuerter Lernprozesse mit digitalen Medien in verschiedenen Forschungsprojekten herausgearbeitet. Ein kritischer Blick auf die Medienentwicklung und die Mediennutzung kann nicht verleugnen, dass es soziokulturelle Unterschiede und Formen sozialer Ungleichheit in der Mediennutzung gibt. In den letzten Jahren entstanden in diesem Zusammenhang vermehrt Studien zu Themenbereichen wie ‹Digital divide›, Zunahme medialer Wissens- und Bildungsklüfte, Bildungsbenachteiligung und Medienaneignung. Verschiedene Fachtagungen griffen die Thematik auf, z.B. der vom JFF Institut für Medienpädagogik in Forschung und Praxis und der Pädagogischen Hochschule Ludwigsburg/Abteilung Medienpädagogik veranstaltete Fachkongress «Soziale Ungleichheit – Medienpädagogik – Partizipation» am 17./18.10.2008 in Bonn und das von der Gesellschaft für Medienpädagogik und Kommunikationskultur e.V. (GMK veranstaltete Forum «Geteilter Bildschirm – Getrennte Welten?» am 21.–23.11.2008 in Rostock. In diesen Studien und Fachtagungen ging es darum herauszuarbeiten, worin soziokulturelle Unterschiede in der Medienaneignung bestehen, was die Gründe hierfür sind, wie diese

  9. A hybridized membrane-botanical biofilter for improving air quality in occupied spaces

    Science.gov (United States)

    Llewellyn, David; Darlington, Alan; van Ras, Niels; Kraakman, Bart; Dixon, Mike

    Botanical biofilters have been shown to be effective in improving indoor air quality through the removal of complex mixtures of gaseous contaminants typically found in human-occupied environments. Traditional, botanical biofilters have been comprised of plants rooted into a thin and highly porous synthetic medium that is hung on vertical surfaces. Water flows from the top of the biofilter and air is drawn horizontally through the rooting medium. These botanical biofilters have been successfully marketed in office and institutional settings. They operate efficiently, with adequate contaminant removal and little maintenance for many years. Depending on climate and outdoor air quality, botanical biofiltration can substantially reduce costs associated with ventilation of stale indoor air. However, there are several limitations that continue to inhibit widespread acceptance: 1. Current designs are architecturally limiting and inefficient at capturing ambient light 2. These biofilters can add significant amounts of humidity to an indoor space. This water loss also leads to a rapid accumulation of dissolved salts; reducing biofilter health and performance 3. There is the perception of potentially actively introducing harmful bioaerosols into the air stream 4. Design and practical limitations inhibit the entrance of this technology into the lucrative residential marketplace This paper describes the hybridization of membrane and botanical biofiltration technologies by incorporating a membrane array into the rootzone of a conventional interior planting. This technology has the potential for addressing all of the above limitations, expanding the range of indoor settings where botanical biofiltration can be applied. This technology was developed as the CSA-funded Canadian component an ESA-MAP project entitled: "Biological airfilter for air quality control of life support systems in manned space craft and other closed environments", A0-99-LSS-019. While the project addressed a

  10. Arbeitsgestaltung und Mitarbeiterqualifizierung

    Science.gov (United States)

    Weiss-Oberdorfer, Werner; Hörner, Barbara; Holm, Ruth; Pirner, Evelin

    Die Wertkette gliedert ein Unternehmen in strategisch relevante Tätigkeiten, um dadurch Kostenverhalten sowie vorhandene und potenzielle Differenzierungsquellen zu verstehen. Wenn ein Unternehmen diese strategisch wichtigen Aktivitäten billiger oder besser als seine Konkurrenten erledigt, verschafft es sich einen Wettbewerbsvorteil." Michael Porter, 1985

  11. Datenschutzrecht und bibliothekarische Praxis

    Directory of Open Access Journals (Sweden)

    Carlheinz Rolf Straub

    2015-03-01

    Full Text Available Bericht zur Fortbildungsveranstaltung des  vdb-Regionalverbandes Südwest zum Thema „Datenschutzrecht und bibliothekarische Praxis“  am 20. November 2014. Report of the training activity held on 20 th, November 2014 by vdb- Regionalverband Südwest.

  12. Wissensmanagement und Medienbildung

    Directory of Open Access Journals (Sweden)

    Gerhard Scheidl

    2012-09-01

    Full Text Available Die Querschnittsthematik "Medienbildung" stößt auf eine immer noch fachzentrierte Ausbildung und Schulpraxis. Mögliche Lösungen könnten Überlegungen aus dem Wissensmanagement bieten, wie Gerhard Scheidl in seinem Beitrag auf verschiedenen Ebenen erläutert.

  13. Tropenbotanik und Phylogenetik

    NARCIS (Netherlands)

    Baumann-Bodenheim, M.G.

    1958-01-01

    Es lässt sich von den Tropenfloren feststellen: 1.) Die Tropenfloren erweitern das morphologische Spektrum des Angiospermen-Systems im Bereiche der systematisch wichtigen Organisationsmerkmale durch ihren Reichtum an eigenen Familien und Gattungen ganz bedeutend. Diese Merkmale stellen oftmals relat

  14. Helicobacter pylori und Magenkarzinom

    Directory of Open Access Journals (Sweden)

    Gschwantler M

    2011-01-01

    Full Text Available Das Magenkarzinom stellt weltweit das vierthäufigste Malignom und die zweithäufigste Todesursache durch Karzinome dar. Die meisten Fälle werden immer noch in einem fortgeschrittenen Stadium mit schlechter Prognose diagnostiziert. Effektive Strategien zur Prävention und Früherkennung sind daher dringend erforderlich. Durch epidemiologische Studien konnte die kausale Beziehung zwischen einer Helicobacterpylori- (H.-p.- Infektion und einem Magenkarzinom eindeutig bewiesen werden. Dabei fördert das Bakterium die Karzinogenese über 2 Mechanismen: (1 über eine indirekte Wirkung durch Induktion einer entzündlichen Reaktion und (2 über direkte Wirkungen auf Zellen der Magenmukosa durch Modulation des Proteinstoffwechsels und Induktion von Genmutationen. Die beiden wichtigsten Virulenzfaktoren von H. p. sind die Pathogenitätsinsel Cag und das vakuolisierende Zytotoxin VacA. Unter klinischen Gesichtspunkten stellt sich die Frage, ob durch eine H.-p.-Eradikation das Risiko, ein Magenkarzinom zu entwickeln, gesenkt werden kann: Insgesamt zeigen die publizierten Studien, dass durch eine H.-p.-Eradikation die Inzidenz des Magenkarzinoms gesenkt werden kann. Durch eine Strategie, in der Normalbevölkerung auf H. p. zu screenen und im Falle einer H.-p.-Infektion eine Eradikationstherapie durchzuführen, kann jedoch nur ein verhältnismäßig geringer Anteil aller Magenkarzinome verhindert werden. Eine solche Strategie ist demnach nur in Ländern mit hoher H.-p.-Prävalenz sinnvoll. Insgesamt deuten die durch Studien in der Normalbevölkerung gewonnenen Daten darauf hin, dass das Magenkarzinomrisiko am effektivsten gesenkt werden kann, wenn die H.-p.-Eradikation frühzeitig, d. h. vor Entwicklung einer atrophen Gastritis, durchgeführt wird. Zusätzlich gibt es überzeugende Daten, dass bei Hochrisikopatienten nach endoskopischer Mukosaresektion eines Magenfrühkarzinoms das Risiko der Entwicklung eines neuerlichen Magenkarzinoms durch eine H

  15. Superkomplexe aus Algen und Cyanobakterien - Isolierung, Charakterisierung und strukturelle Untersuchung

    OpenAIRE

    Heidrich, Nicolas Georges

    2011-01-01

    Seit über 10 Jahren ist bekannt, dass in Mitochondrien von Säugetieren, Pilzen, höheren Pflanzen und Algen die Atmungskettenkomplexe I, III und IV stöchiometrisch als Proteinsuperkomplexe zusammengelagert sind. Diese Superkomplexe bestehen in den bisher bekannten Formen aus einer Kopie von Komplex I, einem Homodimer von Komplex III, welcher nur als solcher aktiv ist, und einer unterschiedlichen Anzahl (0-4) an Komplex IV. Vermutlich erfolgt der Elektronentransport zwischen den Atmungskettenko...

  16. Thermodynamic aspects of heavy metal volatility during utilisation of the energetic and material fraction of waste materials; Schwermetallfluechtigkeit bei der energetischen und stofflichen Verwertung von Abfaellen aus der Sicht der Thermodynamik

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, B.; Starke, A. [TU Bergakademie Freiberg (Germany). Inst. IEC

    1998-09-01

    Co-combustion plants, in which fuel is partly substituted by waste materials, are subject to the 17th BImSchV (Nuisance Control Ordinance) provided that the thermal fraction of 25% is not exceeded. Emission limits are calculated proportionately on the basis of limiting values for emissions from coal power stations (13th BImSchV) and waste incinerators (17th BImSchV). Compared to coal, waste has higher concentrations of heavy metals and halogens, which results in enhanced emissions of heavy metal compounds and chlorides with the flue gas and gasification gas. Plant operators intending to opt for co-combustion must check if the existing flue gas purification system is efficient enough to meet the specifications of the 17th BImSchV. In general, thermodynamic modelling is the most common method of evaluation and optimisation for high-temperature processes of this kind. (orig./SR) [Deutsch] Da bei der Mitverbrennung ein Teil des Brennstoffes durch den Reststoff substituiert wird, unterliegen diese Anlagen der Anteilsregelung nach 17. BImSchV, sofern ein thermischer Anteil von 25% nicht ueberschritten wird. Emissionsgrenzwerte werden anteilig aus den z.B. fuer Kohlekraftwerke gueltigen Grenzwerten nach TA Luft oder 13. BImSchV und denen fuer Abfaelle u.ae. nach 17 BImSchV ermittelt. Der hier betrachtete Reststoff Muell beinhaltet im Vergleich zur Kohle hohe Konzentrationen an Schwermetallen und Halogenen. Dies laesst eine erhoehte Emission von Schwermetallverbindungen und Chloriden mit dem Rauchgas bzw. Vergasungsgas erwarten. Es muss in jedem Fall ueberprueft werden, ob die vorhandene Rauchgasreinigung ausreicht, wenn bei der Mitverbrennung/-vergasung die Emissionsgrenzwerte der 17. BImSchV zur Anwendung kommen. Als Bewertungs- und Optimierungsmethode fuer derartige Hochtemperaturprozesse setzt sich die thermodynamische Modellierung zunehmend durch. (orig./SR)

  17. Modelling the ignition process on the injection jet for Diesel engine combustion; Modellierung des Zuendvorgangs am Einspritzstrahl bei dieselmotorischer Verbrennung

    Energy Technology Data Exchange (ETDEWEB)

    Pitsch, H.; Mueller, U.C.; Peters, N.

    1995-12-31

    A simplified chemical model is developed to describe Diesel engine self-ignition processes. It is assumed that the ignition of Diesel fuel can be described by the single component fuel n-heptane. Starting from a detailed reaction mechanism for n-heptane with about 1000 element reactions and 168 chemical substances, a starting mechanism with 81 element reactions and 37 chemical substances is produced by a reaction flow analysis which can describe ignition processes in conditions relevant for Diesel engines. The introduction of steady state assumptions for quickly consumed intermediate species leads to a reduced mechanism with 14 global reaction steps. In order to prove the validity of these reduced mechanisms, calculated ignition delay times are compared with surge wave tube experiments for different temperatures, pressures and fuel ratios. Finally, one dimensional calculations of ignition processes in the mixing space for pressures and temperatures relevant for engines are introduced. From these, the effect of the scalar dissipation rate which describes the extent of diffusion flames on the ignition delay times, is discussed. An approximation formula for the ignition delay times as a function of the dissipation rate is derived. (orig.) [Deutsch] Zur Beschreibung dieselmotorischer Selbstzuendprozesse wird ein vereinfachtes chemisches Modell entwickelt. Dazu wird angenommen, dass die Zuendung von Dieselkraftstoffen durch den Einkomponentenkraftstoff n-Heptan beschrieben werden kann. Ausgehend von einem detaillierten Reaktionsmechanismus fuer n-Heptan mit ungefaehr 1000 Elementarreaktionen und 168 chemischen Spezies wird mittels einer Reaktionsflussanalyse ein Startmechanismus mit 81 Elementarreaktionen und 37 chemischen Spezies erstellt, der in der Lage ist, Zuendprozesse unter dieselmotorisch relevanten Bedingungen zu beschreiben. Die Einfuehrung von Stationaritaetsannahmen fuer schnell verbrauchte Zwischenspezies fuehrt auf einen reduzierten Mechanismus mit 14

  18. Point defects and electric compensation in gallium arsenide single crystals; Punktdefekte und elektrische Kompensation in Galliumarsenid-Einkristallen

    Energy Technology Data Exchange (ETDEWEB)

    Kretzer, Ulrich

    2007-12-10

    von Modellen, die eine quantitative Beschreibung der experimentell untersuchten elektrischen und optischen Eigenschaften von Galliumarsenid- Einkristallen ausgehend von den Punktdefektkonzentrationen erlauben. Da aus Punktdefekten Ladungstraeger freigesetzt werden koennen, bestimmt ihre Konzentration massgeblich die Ladungstraegerkonzentration in den Baendern. Im ionisierten Zustand wirken Punktdefekte als Streuzentren fuer freie Ladungstraeger und beeinflussen damit die Driftbeweglichkeit der Ladungstraeger. Eine thermodynamische Modellierung der Punktdefektbildung liefert Aussagen ueber die Gleichgewichtskonzentrationen der Punktdefekte in Abhaengigkeit von Dotierstoffkonzentration und Stoechiometrieabweichung. Es wird gezeigt, dass die bei Raumtemperatur beobachteten elektrischen Eigenschaften der Kristalle aus der kinetischen Hemmung von Prozessen folgen, ueber die die Einstellung eines thermodynamischen Gleichgewichts zwischen den Punktdefekten vermittelt wird. (orig.)

  19. Nitrogen removal and microbial characteristics in CANON biofilters fed with different ammonia levels.

    Science.gov (United States)

    Liang, Yuhai; Li, Dong; Zhang, Xiaojing; Zeng, Huiping; Yang, Zhuo; Cui, Shaoming; Zhang, Jie

    2014-11-01

    The nitrogen removal performance and microbial characteristics of four completely autotrophic nitrogen removal over nitrite (CANON) biofilters were investigated. These four reactors were simultaneously seeded from a stable CANON biofilter with a seeding ratio of 1:1, which were fed with different ammonia levels. Results suggested that with the ammonia of 200-400 mg L(-1), aerobic ammonia-oxidizing bacteria (AerAOB) and anaerobic ammonia-oxidizing bacteria (AnAOB) could perform harmonious work. The bioactivity and population of the two groups of bacteria were both high, which then resulted in excellent nitrogen removal, while too low or too high ammonia would both lead to worse performance. When ammonia was too high, the bioactivity, biodiversity and population of AerAOB all decreased and then resulted in the lowest nitrogen removal. Nitrosomonas and Candidatus Brocadia were detected as predominant functional microbes in all the four reactors. Finally, strategies for treating sewage with different ammonia levels were proposed.

  20. A biofilter for treating toluene vapors: performance evaluation and microbial counts behavior

    Science.gov (United States)

    Zhu, Yazhong; Luo, Yimeng; Ma, Hongye; Wang, Yan

    2016-01-01

    A lab-scale biofilter packed with mixed packing materials was used for degradation of toluene. Different empty bed residence times, 148.3, 74.2 and 49.4 s, were tested for inlet concentration ranging from 0.2 to 1.2 g/m3. The maximum elimination capacity of 36.0 g/(m3 h) occurred at an inlet loading rate of 45.9 g/(m3 h). The contribution of the lower layer was higher than other layers and always had the highest elimination capacity. The carbon dioxide production rate and distribution of micro-organisms followed toluene elimination capacities. The results of this study indicated that mixed packing materials could be considered as a potential biofilter carrier, with low pressure drop (less than 84.9 Pa/m), for treating air streams containing VOCs. PMID:27231662

  1. Low-energy treatment of colourant wastes using sponge biofilters for the personal care product industry.

    Science.gov (United States)

    Ahammad, S Z; Zealand, A; Dolfing, J; Mota, C; Armstrong, D V; Graham, D W

    2013-02-01

    Four trickling biofilter designs were assessed as low-energy alternatives to aerobic activated sludge (AS) for the treatment of personal care product industry wastes. The designs included partially submerged packed-media and sponge reactors with and without active aeration. Partial submergence was used to reduce active aeration needs. Simulated colourant wastes (up to COD=12,480 mg/L, TN=128 mg/L) were treated for 201 days, including wastes with elevated oxidant levels. COD and TN removal efficiencies were always >79% and >30% (even without aeration). However, aerated sponge reactors consistently had the highest removal efficiencies, especially for TN (∼60%), and were most tolerant of elevated oxidants. This study shows sponge biofilters have great potential for treating colourant wastes because they achieve high treatment efficiencies and reduce energy use by >40% relative to AS systems.

  2. Evaluating Escherichia coli removal performance in stormwater biofilters: a laboratory-scale study.

    Science.gov (United States)

    Chandrasena, G I; Deletic, A; Ellerton, J; McCarthy, D T

    2012-01-01

    Biofilters are common, low energy technologies used for the treatment of urban stormwater. While they have shown promising results for the removal of stormwater microorganisms, certain factors affect their performance. Hence, this study investigated the effects of particle-microbial interaction, inflow concentration, antecedent microbial levels and plant species on microbial removal capacity. A biofilter column study was set up to evaluate removal performance and a sequential filtration procedure was used to estimate microbial partitioning. The columns were dosed with different concentrations of free phase Escherichia coli only and E. coli mixed with stormwater sediment. Results indicate that the microbial removal is significantly affected by inflow concentration and antecedent microbial levels. Leaching was only observed when a relatively low inflow concentration event occurred within a short period after a very high inflow concentration event. Finally, Lomandra longifolia showed better removal compared with Carex appressa.

  3. Influence of the water content and water activity on styrene degeneration by Exophiala jeanselmei in biofilters

    Energy Technology Data Exchange (ETDEWEB)

    Cox, H.H.J. [TNO Inst. of Environmenal Sciences, Energy Research and Process Inovation, Dept. of Environmental Biotechnology, Delf (Netherlands); Magielsen, F.J. [TNO Inst. of Environmenal Sciences, Energy Research and Process Inovation, Dept. of Environmental Biotechnology, Delf (Netherlands); Doddema, H.J. [TNO Inst. of Environmenal Sciences, Energy Research and Process Inovation, Dept. of Environmental Biotechnology, Delf (Netherlands); Harder, W. [TNO Inst. of Environmenal Sciences, Energy Research and Process Inovation, Dept. of Environmental Biotechnology, Delf (Netherlands)

    1996-12-31

    The performance at low water availability of styrene-degrading biofilters with the fungus Exophiala jeanselmei growing on perlite, the inert support, was investigated. E. jeanselmei degrades styrene at a water activity of 0.91-1. In biofilters, the styrene elimination capacity at a water activity of 0.91 is 5% of the maximal elimination capacity of 79 g m{sup -3} h{sup -1} (water activity 1). Application of dry air results in a rapid loss of styrene degradation activity, even at 40%-60% (w/w) water in the filter bed and at a water activity of 1. Humidification of the gas and an additional supply of water to the filter bed are necessary to maintain a high and stable styrene elimination capacity. (orig.)

  4. Fate of water borne therapeutic agents and associated effects on nitrifying biofilters in recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming

    Recent discharge restrictions on antibiotics and chemotherapeutant residuals used in aquaculture have several implications to the aquaculture industry. Better management practices have to be adopted, and documentation and further knowledge of the chemical fate is required for proper administration...... and to support the ongoing development of a sustainable aquaculture industry. A focal point of this thesis concerns formaldehyde (FA), a commonly used chemical additive with versatile aquaculture applications. FA is safe for use with fish and has a high treatment efficiency against fungal and parasite infections...... of these agents on biofilter nitrification performance. All experiments were conducted through addition of chemical additives to closed pilot scale recirculating aquaculture systems (RAS) with fixed media submerged biofilters under controlled operating conditions with rainbow trout (Oncorhynchus mykiss...

  5. Relevance and diversity of Nitrospira populations in biofilters of brackish RAS.

    Science.gov (United States)

    Kruse, Myriam; Keuter, Sabine; Bakker, Evert; Spieck, Eva; Eggers, Till; Lipski, André

    2013-01-01

    Lithoautotrophic nitrite-oxidizing bacterial populations from moving-bed biofilters of brackish recirculation aquaculture systems (RAS; shrimp and barramundi) were tested for their metabolic activity and phylogenetic diversity. Samples from the biofilters were labeled with (13)C-bicarbonate and supplemented with nitrite at concentrations of 0.3, 3 and 10 mM, and incubated at 17 and 28°C, respectively. The biofilm material was analyzed by fatty acid methyl ester - stable isotope probing (FAME-SIP). High portions of up to 45% of Nitrospira-related labeled lipid markers were found confirming that Nitrospira is the major autotrophic nitrite oxidizer in these brackish systems with high nitrogen loads. Other nitrite-oxidizing bacteria such as Nitrobacter or Nitrotoga were functionally not relevant in the investigated biofilters. Nitrospira-related 16S rRNA gene sequences were obtained from the samples with 10 mM nitrite and analyzed by a cloning approach. Sequence studies revealed four different phylogenetic clusters within the marine sublineage IV of Nitrospira, though most sequences clustered with the type strain of Nitrospira marina and with a strain isolated from a marine RAS. Three lipids dominated the whole fatty acid profiles of nitrite-oxidizing marine and brackish enrichments of Nitrospira sublineage IV organisms. The membranes included two marker lipids (16∶1 cis7 and 16∶1 cis11) combined with the non-specific acid 16∶0 as major compounds and confirmed these marker lipids as characteristic for sublineage IV species. The predominant labeling of these characteristic fatty acids and the phylogenetic sequence analyses of the marine Nitrospira sublineage IV identified organisms of this sublineage as main autotrophic nitrite-oxidizers in the investigated brackish biofilter systems.

  6. Relevance and diversity of Nitrospira populations in biofilters of brackish RAS.

    Directory of Open Access Journals (Sweden)

    Myriam Kruse

    Full Text Available Lithoautotrophic nitrite-oxidizing bacterial populations from moving-bed biofilters of brackish recirculation aquaculture systems (RAS; shrimp and barramundi were tested for their metabolic activity and phylogenetic diversity. Samples from the biofilters were labeled with (13C-bicarbonate and supplemented with nitrite at concentrations of 0.3, 3 and 10 mM, and incubated at 17 and 28°C, respectively. The biofilm material was analyzed by fatty acid methyl ester - stable isotope probing (FAME-SIP. High portions of up to 45% of Nitrospira-related labeled lipid markers were found confirming that Nitrospira is the major autotrophic nitrite oxidizer in these brackish systems with high nitrogen loads. Other nitrite-oxidizing bacteria such as Nitrobacter or Nitrotoga were functionally not relevant in the investigated biofilters. Nitrospira-related 16S rRNA gene sequences were obtained from the samples with 10 mM nitrite and analyzed by a cloning approach. Sequence studies revealed four different phylogenetic clusters within the marine sublineage IV of Nitrospira, though most sequences clustered with the type strain of Nitrospira marina and with a strain isolated from a marine RAS. Three lipids dominated the whole fatty acid profiles of nitrite-oxidizing marine and brackish enrichments of Nitrospira sublineage IV organisms. The membranes included two marker lipids (16∶1 cis7 and 16∶1 cis11 combined with the non-specific acid 16∶0 as major compounds and confirmed these marker lipids as characteristic for sublineage IV species. The predominant labeling of these characteristic fatty acids and the phylogenetic sequence analyses of the marine Nitrospira sublineage IV identified organisms of this sublineage as main autotrophic nitrite-oxidizers in the investigated brackish biofilter systems.

  7. Theoretical model for removal of volatile organic compound (VOC) air pollutant in trickling biofilter

    Institute of Scientific and Technical Information of China (English)

    LIAO; Qiang; (廖; 强); CHEN; Rong; (陈; 蓉); ZHU; Xun; (朱; 恂)

    2003-01-01

    This paper presents an analytical model for predicting VOC waste gas degradation in a trickling biofilter. To facilitate the analysis, the packed bed is simplified into a series of straight capillary tubes covered by the biofilm. The gas-liquid flow field through the tube is divided into the liquid film flow on the biofilm and the gas core flow in the center. The biofilm consists of a reaction free zone close to solid wall and a reaction zone beneath the liquid film. The capillary tube model accounts for the effect of mass transport resistance in the liquid film and the biofilm, the gas-liquid interfacial mass transport resistance, the biochemical reaction, and the limitation of oxygen to biochemical reaction. The liquid film thickness in the capillary tube is obtained by simultaneously solving a set of hydrodynamic equations representing the momentum transport behaviors of the gas-liquid two-phase flow. The mass transport equations are established for gas core, liquid film, and biofilm combined with biochemical kinetics equations. An iterative computation process is employed to solve the discrete equations. The predicted purification efficiencies of VOC waste gas in trickling biofilter are found to be in good agreement with the experimental data. It has been revealed that for a fixed inlet concentration of toluene, the purification efficiency of trickling biofilter decreases with the increase in gas flow rate and liquid flow rate. The purification efficiency of VOC waste gas is dominated by mass transport resistance in liquid film and biofilm. The highest biodegradation rate occurs at the inlet of waste gas in trickling biofilter.

  8. Community Analysis and Recovery of Phenol-degrading Bacteria from Drinking Water Biofilters.

    Science.gov (United States)

    Gu, Qihui; Wu, Qingping; Zhang, Jumei; Guo, Weipeng; Wu, Huiqing; Sun, Ming

    2016-01-01

    Phenol is a ubiquitous organic contaminant in drinking water. Biodegradation plays an important role in the elimination of phenol pollution in the environment, but the information about phenol removal by drinking water biofilters is still lacking. Herein, we study an acclimated bacterial community that can degrade over 80% of 300 mg/L phenol within 3 days. PCR detection of genotypes involved in bacterial phenol degradation revealed that the degradation pathways contained the initial oxidative attack by phenol hydroxylase, and subsequent ring fission by catechol 1,2-dioxygenase. Based on the PCR denatured gradient gel electrophoresis (PCR-DGGE) profiles of bacteria from biological activated carbon (BAC), the predominant bacteria in drinking water biofilters including Delftia sp., Achromobacter sp., and Agrobacterium sp., which together comprised up to 50% of the total microorganisms. In addition, a shift in bacterial community structure was observed during phenol biodegradation. Furthermore, the most effective phenol-degrading strain DW-1 that correspond to the main band in denaturing gradient gel electrophoresis (DGGE) profile was isolated and identified as Acinetobacter sp., according to phylogenetic analyses of the 16S ribosomal ribonucleic acid (rRNA) gene sequences. The strain DW-1 also produced the most important enzyme, phenol hydroxylase, and it also exhibited a good ability to degrade phenol when immobilized on granular active carbon (GAC). This study indicates that the enrichment culture has great potential application for treatment of phenol-polluted drinking water sources, and the indigenous phenol-degrading microorganism could recover from drinking water biofilters as an efficient resource for phenol removal. Therefore, the aim of this study is to draw attention to recover native phenol-degrading bacteria from drinking water biofilters, and use these native microorganisms as phenolic water remediation in drinking water sources.

  9. Community analysis and recovery of phenol-degrading bacteria from drinking water biofilters

    Directory of Open Access Journals (Sweden)

    Qihui eGu

    2016-04-01

    Full Text Available Phenol is a ubiquitous organic contaminant in drinking water. Biodegradation plays an important role in the elimination of phenol pollution in the environment, but the information about phenol removal by drinking water biofilters is still lacking. Herein, we study an acclimated bacterial community that can degrade over 80% of 300 mg/L phenol within 3 d. PCR detection of genotypes involved in bacterial phenol degradation revealed that the degradation pathways contained the initial oxidative attack by phenol hydroxylase, and subsequent ring fission by catechol 1,2-dioxygenase. Based on the PCR denatured gradient gel electrophoresis (PCR-DGGE profiles of bacteria from biological activated carbon (BAC, the predominant bacteria in drinking water biofilters including Delftia sp., Achromobacter sp., and Agrobacterium sp., which together comprised up to 50% of the total microorganisms. In addition, a shift in bacterial community structure was observed during phenol biodegradation. Furthermore, the most effective phenol-degrading strain DW-1 that correspond to the main band in DGGE profile was isolated and identified as Acinetobacter sp., according to phylogenetic analyses of the 16S ribosomal ribonucleic acid (rRNA gene sequences. The strain DW-1 also produced the most important enzyme, phenol hydroxylase, and it also exhibited a good ability to degrade phenol when immobilized on GAC. This study indicates that the enrichment culture has great potential application for treatment of phenol-polluted drinking water sources, and the indigenous phenol-degrading microorganism could recover from drinking water biofilters as an efficient resource for phenol removal. Therefore, the aim of this study is to draw attention to recover native phenol-degrading bacteria from drinking water biofilters, and use these native microorganisms as phenolic water remediation in drinking water sources.

  10. Dynamic olfactometry and GC–TOFMS to monitor the efficiency of an industrial biofilter

    Energy Technology Data Exchange (ETDEWEB)

    Gutiérrez, M.C.; Martín, M.A. [University of Cordoba, Department of Inorganic Chemical and Chemical Engineering, Campus Universitario de Rabanales, Carretera N-IV, km 396, Edificio Marie Curie, 14071 Córdoba (Spain); Pagans, E.; Vera, L. [Odournet SL, Parc de Recerca UAB, Edificio Eureka, Espacio P2M2, 08193, Bellaterra, Cerdanyola del Vallès, Barcelona (Spain); García-Olmo, J. [NIR/MIR Spectroscopy Unit, Central Service for Research Support (SCAI), University of Cordoba, Campus de Rabanales, 14071 Cordoba (Spain); Chica, A.F., E-mail: afchica@uco.es [University of Cordoba, Department of Inorganic Chemical and Chemical Engineering, Campus Universitario de Rabanales, Carretera N-IV, km 396, Edificio Marie Curie, 14071 Córdoba (Spain)

    2015-04-15

    Biofiltration is the most widely used technique for eliminating odours in waste treatment plants. Volatile organic compounds (VOCs) are among the odorous compounds emitted by waste management plants, and serve as variables to measure odour emissions depending on the type of aeration process used. In this work, we assess the performance of an industrial-scale biofilter where composting is the main source of VOCs and odour emissions. Dynamic olfactometry is the sensorial technique used to determine odour concentration, while gas chromatography–time of flight-mass spectrometry (GC–TOFMS) is used to perform the chemical characterization. This work examines a total of 82 compounds belonging to 15 odorous families of VOCs, particularly mercaptans, sulphur-containing compounds, alcohols and terpenes, among others. Principal component analysis (PCA) is used to assess the influence of each of these families of VOCs on the total variance of the measure with regard to both the input and output flow of the biofilter. Finally, partial least-squares (PLS) regression is used to estimate the odour concentration in each of the samples taken at the inlet and outlet of the biofilter in each of the samples based on the chemical information provided by chromatographic analysis. The study shows that there is an adequate correlation (r = 0.9751) between real and estimated odour concentrations, both of which are expressed in European odour units per cubic metre (ou{sub E}·m{sup −3}). - Highlights: • Odour and VOC removal by industrial biofilter was evaluated. • Dynamic olfactometry and GC-TOF MS were the techniques used. • The compost aeration mode was considered in this study. • The influence of 15 VOC families on sample variance was demonstrated by PCA. • Odour concentration was predicted from selected chromatographic information by PLS.

  11. Evaluation of the Efficiency of a Biofilter System’s Phenol Removal From Wastewater

    Directory of Open Access Journals (Sweden)

    Reza Shokoohi

    2016-06-01

    Full Text Available Phenol is a toxic hydrocarbon that has been found in the wastewater of several industries, including the petroleum and petrochemical industries. The discharge of untreated wastewater from these industries causes environmental pollution, especially in water. The aim of this study was to evaluate the efficiency of phenol removal from wastewater using a biofiltration system. In this experimental study, a cylindrical plexiglass biofilter reactor with an effective volume of 12 liters was used. A total of 30 pcs of plastic grid discs were placed inside the reactor by plastic pipes to maintain the biofilm media in the reactor. The microorganisms used in this study were obtained from the biological sludge of a municipal wastewater treatment plant. The reproduction and adaptation of the microorganisms to 500 mg/L of phenol lasted three months. The effects of pH, phenol, nitrogen, phosphorus, glucose concentration, and hydraulic retention time on the biofilter system’s performance was evaluated. The results of this study showed that in optimal conditions, this system can reduce the phenol concentration from 500 mg/L to zero within about 4 hr. Maximum efficiency occurred in pH = 7, and the proper COD/N/P ratio was 100/10/2, respectively. In general, this biofilter system is capable of removing 500 mg/L of phenol concentrations and an organic load of 4 - 4.5 kg COD/m3.d within 4 - 5 hr. with high efficiency.

  12. Nitrite accumulation during denitrification depends on the carbon quality and quantity in wastewater treatment with biofilters.

    Science.gov (United States)

    Rocher, Vincent; Laverman, Anniet M; Gasperi, Johnny; Azimi, Sam; Guérin, Sabrina; Mottelet, Stéphane; Villières, Thierry; Pauss, André

    2015-07-01

    This study aims to understand the mechanisms of nitrite appearance during wastewater denitrification by biofilters, focusing on the role of the carbon source. Experiments were carried out at lab-scale (batch tests) and full-scale plant (Parisian plant, capacities of 240,000 m(3) day(-1)). Results showed that the nature of the carbon source affects nitrite accumulation rates. This accumulation is low, 0.05 to 0.10 g N-NO2(-) per g N-NO3(-) eliminated, for alcohols such as methanol, ethanol, or glycerol. The utilization of glycerol leads to fungal development causing clogging of the biofilters. This fungal growth and consequent clogging exclude this carbon source, with little nitrite accumulation, as carbon source for denitrification. Whatever the carbon source, the C/N ratio in the biofilter plays a major role in the appearance of residual nitrite; an optimal C/N ratio from 3.0 to 3.2 allows a complete denitrification without any nitrite accumulation.

  13. Changes in the potential functional diversity of the bacterial community in biofilters

    Energy Technology Data Exchange (ETDEWEB)

    Grove, J.A.; Anderson, W.A.; Moo-Young, M. [Waterloo Univ., ON (Canada). Dept. of Chemical Engineering

    2007-12-15

    The bacterial community structure in a biofilter treating ethanol was investigated using community level physiological profiling. Laboratory scale biofilters of two sizes (5 or 11.5 cm internal diameter with 30 or 67 cm packed height, respectively) were packed with compost and a humidified airstream loaded with ethanol passed through them. Good removal efficiencies (82-100%) and elimination capacities (49-205 g ethanol m{sup -3} h{sup -1}) were observed in all units. Compost packing media samples were extracted and the community level physiological profiles assayed using Biolog Ecoplates. The community structure was found to be similar over a range of a few centimetres. No differences were observed between sample sizes of 0.5-1 and 6 g, and therefore, the smaller sample size (typical of that used in previous studies) is appropriate for use in the future. Two studies of parallel systems showed that the community structure diverged during the acclimation period (10 days) in one pair, but in another pair, no divergence was observed and a similar shift in community profile was observed in both units between 25 and 40 days of operation. Community level physiological profiling with Biolog Ecoplates is a useful method for detecting differences between and changes within the bacterial communities in biofilters. (orig.)

  14. The Efficiency of Biofilters at Mitigating Airborne MRSA from a Swine Nursery.

    Science.gov (United States)

    Ferguson, D D; Smith, T C; Donham, K J; Hoff, S J

    2015-10-01

    Our prior studies have been in agreement with other researchers in detecting airborne methicillin-resistant Staphylococcus aureus (MRSA) inside and downwind of a swine housing facility. MRSA emitted in the exhaust air of swine facilities creates a potential risk of transmission of these organisms to people in the general area of these facilities as well as to other animals. This study investigated a possible means of reducing those risks. We investigated the efficiency of biofilters to remove MRSA from the exhaust air of a swine building. Two types of biofilter media (hardwood chips and western red cedar shredded bark) were evaluated. Efficiency was measured by assessing both viable MRSA (viable cascade impactor) and dust particles (optical particle courter) in the pre-filtered and post-filtered air of a functioning swine production facility. Our study revealed that hardwood chips were respectively 92% and 88% efficient in removing viable MRSA and total dust particles. Western red cedar was 95% efficient in removing viable MRSA and 86% efficient in removing dust particles. Our findings suggest that biofilters can be used as effective engineering controls to mitigate the transmission of aerosolized MRSA in the exhaust air of enclosed swine housing facilities.

  15. Influence of intermittent wetting and drying conditions on heavy metal removal by stormwater biofilters.

    Science.gov (United States)

    Blecken, Godecke-Tobias; Zinger, Yaron; Deletić, Ana; Fletcher, Tim D; Viklander, Maria

    2009-10-01

    Biofiltration is a technology to treat urban stormwater runoff, which conveys pollutants, including heavy metals. However, the variability of metals removal performance in biofiltration systems is as yet unknown. A laboratory study has been conducted with vegetated biofilter mesocosms, partly fitted with a submerged zone at the bottom of the filter combined with a carbon source. The biofilters were dosed with stormwater according to three different dry/wet schemes, to investigate the effect of intermittent wetting and drying conditions on metal removal. Provided that the biofilters received regular stormwater input, metal removal exceeded 95%. The highest metal accumulation occurs in the top layer of the filter media. However, after antecedent drying before a storm event exceeding 3-4 weeks the filters performed significantly worse, although metal removal still remained relatively high. Introducing a submerged zone into the filter improved the performance significantly after extended dry periods. In particular, copper removal in filters equipped with a submerged zone was increased by around 12% (alpha=0.05) both during wet and dry periods and for lead the negative effect of drying could completely be eliminated, with consistently low outflow concentrations even after long drying periods.

  16. E. coli removal in laboratory scale stormwater biofilters: Influence of vegetation and submerged zone

    Science.gov (United States)

    Chandrasena, G. I.; Pham, T.; Payne, E. G.; Deletic, A.; McCarthy, D. T.

    2014-11-01

    Biofilters, also known as bioretention areas or raingardens, are an effective treatment option for the removal of various pollutants from stormwater. However, they show variable treatment efficiency for the removal of indicator bacteria, and the operational and design factors which impact this variability are largely unknown. This study uses a laboratory scale column set-up to explore how Escherichia coli (the chosen indicator organism) removal in the stormwater biofilters is impacted by: plant presence and species type, the presence of a submerged zone (SZ), and operational conditions (duration of dry periods and changes over the initial stages of the system's life-span). Vegetation selection was found to be important for E. coli removal and the highly performing plant species were associated with lower infiltration rates. Based on the current results, a biofilter planted with Leptospermum continentale, Melaleuca incana or Palmetto buffalo and comprising a SZ can be recommended for improved E. coli removal. Inclusion of SZ was found to generally enhance the removal performance; which may be explained by the contribution of microbial processes that are happening within the SZ (such as predation/competition and natural die-off). Results also suggest that the E. coli removal performance is reduced after a significant dry period, while the overall removal performance improves over time as systems mature.

  17. Characterization of the microbial community structure and nitrosamine-reducing isolates in drinking water biofilters.

    Science.gov (United States)

    Wang, Wanfeng; Guo, Yanling; Yang, Qingxiang; Huang, Yao; Zhu, Chunyou; Fan, Jing; Pan, Feng

    2015-07-15

    Two biofilters were constructed using biological activated carbon (BAC) and nitrosamine-containing water from two drinking water treatment plants. The microbiome of each biofilter was characterized by 454 high-throughput pyrosequencing, and one nitrosamine-reducing bacterium was isolated. The results showed that nitrosamines changed the relative abundance at both the phylum and class levels, and the new genera were observed in the microbial communities of the two BAC filters after cultivation. As such, the genus Rhodococcus, which includes many nitrosamine-reducing strains reported in previous studies, was only detected in the BAC2 filter after cultivation. These findings indicate that nitrosamines can significantly affect the genus level in the microbial communities. Furthermore, the isolated bacterial culture Rhodococcus cercidiphylli A41 AS-1 exhibited the ability to reduce five nitrosamines (N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosodi-n-propylamine, N-nitrosopyrrolidine, and N-nitrosodi-n-butylamine) with removal ratios that ranged from 38.1% to 85.4%. The isolate exhibited a better biodegradation ability with nitrosamine as the carbon source when compared with nitrosamine as the nitrogen source. This study increases our understanding of the microbial community in drinking water biofilters with trace quantities of nitrosamines, and provides information on the metabolism of nitrosamine-reducing bacteria.

  18. Performance of a biofilter system with agave fiber filter media for municipal wastewater treatment.

    Science.gov (United States)

    Vigueras-Cortés, Juan Manuel; Villanueva-Fierro, Ignacio; Garzón-Zúñiga, Marco Antonio; de Jesús Návar-Cháidez, José; Chaires-Hernández, Isaías; Hernández-Rodríguez, César

    2013-01-01

    Agave plants grow in semi-arid regions and are used for mescal production. However, agave fiber by-products are considered waste materials. Thus, we tested agave fiber as a filter media and biofilm material carrier for removing pollutants from municipal wastewater. Three laboratory-scale biofiltration reactors were used in two trials with five hydraulic loading rates (HLRs = 0.27, 0.54, 0.80, 1.07 and 1.34 m(3) m(-2) d(-1)). One series was conducted using mechanical aeration (0.62 m(3) m(-2) h(-1)). To prevent compaction, decreasing pressure and clogging of the filter media, 4, 8 and 12 internal divisions were evaluated in the biofilter column. After 17 months of continuous operation at an HLR of 0.80 m(3) m(-2) d(-1), the removal efficiencies of the aerated biofilters were 92.0% biochemical oxygen demand, 79.7% chemical oxygen demand, 98.0% helminth eggs, 99.9% fecal coliforms and 91.9% total suspended solids. Statistical analysis showed that the chosen operational parameters significantly influenced the removal efficiencies of the biofilters. The effluent quality obtained under these conditions complied with the Mexican and US EPA standards for agricultural irrigation and green spaces, except for coliforms, which is why the effluents must be disinfected. Thus, agave fiber is a favorable choice for use as a packing material in biofiltration processes.

  19. Specific biofilter process design using bacteria capable of removing hydrogen sulphide from air emissions

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, R.N. [Alberta Environmental Centre, Vegreville, AB (Canada)

    1996-05-01

    The design and development of a biofilter unit which can remove hydrogen sulphide (H{sub 2}S) from air emissions, such as those found in the oil and gas industry and the Kraft wood pulping process, was discussed. Biofilters which contain species of bacteria which are able to oxidize H{sub 2}S have been very successful in removing high concentrations of H{sub 2}S from contaminated air streams. The biofilters could control noxious or offensive odours through aerobic metabolism of contaminants by microorganisms attached to such surfaces as peat or wood bark. Microbial oxidation of low molecular weight inorganic and volatile organic compounds were shown to result in their degradation to end products such as carbon dioxide, sulphate, water and new cell biomass. Research was directed toward the treatment of sulphur containing emissions generated during the sulphide recovery cycle in the Kraft wood pulping process, but since emissions are similar to those present in oil and gas industry, this technology was said to be equally applicable in the petroleum industry. 14 refs., 5 tabs., 8 figs.

  20. Phase transformation and local mechanical properties of TRIP steel in a simulated and real resistance spot weld process; Phasenumwandlung und lokale mechanische Eigenschaften von TRIP Stahl beim simulierten und realen Widerstandspunktschweissprozess

    Energy Technology Data Exchange (ETDEWEB)

    Brauser, Stephan

    2013-06-01

    praeparierter Zugproben und den mittels Metallographisch wie auch roentgenographisch ermittelten Austenitgehalten konnten die metastabilen, d.h. umwandlungsfaehigen Austenitanteile bestimmt werden. Schliesslich erfolgte eine Bewertung hinschlich der Uebertragbarkeit der Ergebnisse auf reale Widerstandspunktschweissverbindungen. Es wurde dabei der Nachweis erbracht, dass die Austenit-Martensit-Phasenumwandlung lediglich in einem lokal eng begrenzen Werkstoffbereich am Uebergang WEZ/Grundwerkstoff wirksam werden kann. Demzufolge fuehrt der TRIP-Effekt zu keiner signifikanten Beeinflussung von Festigkeits- und Verformungseigenschaften im Fuegebereich von widerstandspunktgeschweissten TRIP Staehlen. Die ermittelten mechanischen Kennwerte wurden abschliessend als Eingangsdaten fuer die numerische Simulation des Verformungs- und Festigkeitsverhaltens von Punkschweissverbindungen genutzt. Dabei wurde insbesondere die Notwendigkeit der Implementierung von mechanischen Kenndaten der Waermeeinflusszone fuer eine realitaetsnahe Modellierung von Scherzugversuchen untersucht.

  1. Genomweites Expressionsprofil skelettaler Tumore und funktionelle Analyse der Ephrine und CD52 in Osteosarkomen und Riesenzelltumoren

    OpenAIRE

    Günther, Raphaela

    2008-01-01

    Knochentumore stellen mit nur 0,2% aller menschlichen Tumore sehr seltene primäre Neoplasien des skelettalen Systems dar. Diese Dissertation beschreibt die genomweite Microarray Analyse von Osteosarkomen und Riesenzelltumoren. Mit einer Microarray Analyse von konventionellen und metastatischen Osteosarkom-Geweben verglichen zu einer Osteoblasten-Primärkultur (HOBc) wurden Gene ermittelt, die im Prozess der Entstehung und Entwicklung sowie im Verlauf der Metastasierung von Osteosarkomen...

  2. Editorial: Computerspiele und Videogames in formellen und informellen Bildungskontexten

    Directory of Open Access Journals (Sweden)

    Johannes Fromme

    2008-01-01

    Full Text Available Computer- und Videospiele sind heute ein selbstverständlicher Bestandteil der Lebenswelt vieler Kinder und Jugendlicher, aber auch von (jüngeren Erwachsenen, die mit diesen neuen Medien aufgewachsen sind. Lange Zeit haben elektronische Bildschirmspiele allenfalls sporadische Beachtung gefunden. Weder in der Medienforschung oder Medienpädagogik noch in der breiteren Öffentlichkeit waren sie ein Gegenstand von breiterem Interesse.* In den letzten knapp zehn Jahren sind Video- und Computerspiele allerdings zunehmend in den Fokus der Aufmerksamkeit gerückt. Dabei sind in der massenmedial vermittelten Öffentlichkeit vor allem Amokläufe in Schulen in einen direkten Zusammenhang mit den Vorlieben (der Täter für bestimmte Computerspiele gebracht worden. Die auch von prominenten Politikern aufgegriffene These lautete, dass gewalthaltige Spiele wie der First Person Shooter «Counterstrike» ein virtuelles Trainingsprogramm für das Töten und daher als wesentliche Ursache solcher Schulmassaker anzusehen seien. Auf der Basis dieser kausalen Wirkungsannahmen bzw. der unterstellten negativen Lern- und Trainingseffekte werden seither immer wieder Forderungen nach einem Verbot solcher «Killerspiele» oder gar nach der Verbannung aller Bildschirmmedien aus den Kinderzimmern abgeleitet. Neben solcher skandalisierter Thematisierung ist aber zunehmend auch eine nüchterne wissenschaftliche Auseinandersetzung zu konstatieren. So haben sich seit Beginn des neuen Jahrtausends die «digital game studies» als interdisziplinäres Forschungsfeld etabliert. Im Jahr 2000 wurde innerhalb der Gesellschaft für Medienwissenschaft z.B. die AG Games gebildet, die sich zu einem wichtigen deutschsprachigen Forum für die wissenschaftliche Beschäftigung mit Computerspielen entwickelt hat, und im Jahr 2002 entstand die internationale Digital Games Research Association (DiGRA, die im September 2009 ihre vierte grosse Konferenz nach 2003, 2005 und 2007 durchgeführt hat

  3. Sozialtheoretische und -interventorische Paradigmen im Licht der sozialen Netzwerk- und Unterstützungsperspektive : Konvergenzen und Herausforderungen

    OpenAIRE

    2006-01-01

    Die Netzwerkperspektive hat vielfältige theoriebezogene Bezüge zu benachbarten disziplinären und professionellen Konzepten (Sozialpädagogik/Sozialarbeit, Sozialpsychologie, Arbeits- und Betriebspsychologie, Stress- und Belastungsforschung, Rehabilitationswissenschaften, Soziale Gerontologie, Pflege- und Gesundheitswissenschaften, Gemeindepsychologie, Familienforschung, systemische Therapieansätze usw.). Innerhalb dieser disziplinären Bezuge lassen sich - implizite oder explizite - intensive B...

  4. 固定化细胞滤床和生物膜滤床净化二甲苯的比较%Comparison of air-borne xylene biodegradation between immobilized-cell biofilter and biofilm attached biofilter

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Bacillus firmus was immobilized into Ca- alginate beads according to the different initial biomass concentration, calcification time and activation time. Three types of immobilized Bacillus firmus beads were packed respectively in trickling biofilter to purify xylene contained waste gases, and the performance of immobilized-cell biofilter was compared with traditional biofilm attached biofilter packed with two types of ceramic pellets. The results showed that three types of immobilized beads had different capabilities for removing xylene and life-spans. Higher initial biomass in immobilized beads resulted in better performance but shorter life-span. Activation process can remarkably enhance the activity of bacteria, and the removal efficiency of xylene can substantially be improved. Calcification time had influence on life-span of immobilized beads. Without acclimation, the cell-entrapped biofilter can obtain the maximum elimination capacity of 92.4 g/(m3·h). However, compared with biofilm attached biofilter, it has a poorer intrinsic drawback in volatile organic compounds (VOCs) removal due to the existence of excess mass transfer resistance.

  5. Rheuma und Haut

    Directory of Open Access Journals (Sweden)

    Zangerl G

    2009-01-01

    Full Text Available Viele Erkrankungen aus dem rheumatischen Formenkreis manifestieren sich auch an der Haut des Patienten und können dort leicht nachgewiesen werden. Gerade bei Kollagenosen oder der Psoriasisarthritis finden sich im Rahmen der Inspektion des Hautmantels entscheidende Hinweise für die Zuordnung des Krankheitsbildes. In manchen Fällen können sich auch schwere Komplikationen ankündigen, Beispiele dafür sind eine Vaskulitis bei einer rheumatoiden Arthritis, aber auch schwere Nebenwirkungen der medikamentösen Therapien (Lyell-Syndrom und ähnliche Veränderungen. In diesem Artikel sollen daher einige der markantesten Hautläsionen bei rheumatischen Erkrankungen kurz besprochen werden.

  6. Epilepsie und Schwangerschaft

    Directory of Open Access Journals (Sweden)

    Luef G

    2009-01-01

    Full Text Available Epilepsien sind eine der häufigsten neurologischen Erkrankungen und umfassen eine Vielzahl von heterogenen Erkrankungen, welche epileptische Anfälle als gemeinsames Symptom besitzen. Schwangerschaften epilepsiekranker Frauen beschäftigen Neurologen und Gynäkologen gleich häufig, da sowohl epileptische Anfälle mit tonisch-klonischen Krämpfen, als auch deren medikamentöse Therapie teratogen sein können. Über 90 % der Schwangerschaften epilepsiekranker Frauen verlaufen weitgehend problemlos. Auch die Anfallsfrequenz ist nur bei sehr wenigen Patientinnen gesteigert. Trotzdem ist es wichtig, dass im speziellen Fall schwangerer Epilepsiepatientinnen verschiedene Fachkräfte zusammenarbeiten. Eine Epilepsie stellt also in der Regel keinen Grund dar, auf Kinder zu verzichten.

  7. Hegel und Gorgias

    DEFF Research Database (Denmark)

    Huggler, Jørgen

    Hegel und Gorgias /Jørgen Huggler (University of Aarhus, Denmark) (huggler(at)dpu.dk) Hegels Verständnis des Sophist Gorgias von Leontinoi in den Vorlesungen über die Geschichte der Philosophie gründet auf seine eigene Interpretation der Eleaten, insbesondere Zenon. Aufgrund eigener philosophischer...... Bemühungen hatte Hegel eine einzigartige Interpretation entwickelt über diese Gruppe von vorsokratischen Philosophen. Insbesonders identifizierte er eine sogenannt "objektive" immanente Dialektik bei Zenon. Nach Hegel haben die Sophisten, mit ihrem Konzept der „Bildung“ und ihren reflektierte Ansicht von...... „Gründen“, einen echten Beitrag zu dieser Entwicklung des griechischen Denkens geliefert. Vor allen scheint Gorgias die dialektischen Bemühungen der Eleaten fortgesetzt zu haben. Hegels Auslegung des Gorgias kann den lauwarmen Empfang der Sophisten in den deutschen Beiträgen zur Geschichte der Philosophie...

  8. Zystische Pankreastumoren: Diagnostik und Therapie

    Directory of Open Access Journals (Sweden)

    Siveke JT

    2013-01-01

    Full Text Available Die Gruppe der zystischen Pankreastumoren umfasst eine Vielzahl verschiedener Entitäten mit unterschiedlichen klinischen, morphologischen und prognostischen Charakteristika. Die Läsionen werden aufgrund der stetig verbesserten Bildgebung zunehmend früher und mit geringerer Größe diagnostiziert. Trotz des breiten Spektrums möglicher Ursachen entfallen 95 % aller zystischen Prozesse auf nur 5 Entitäten: Pankreaspseudozysten, intraduktale papilläre muzinöse Neoplasien (IPMN, muzinös-zystische Neoplasien (MCN, serös-zystische Neoplasien (SCN und solid-pseudopapilläre Neoplasien (SPN. Relevant ist die Unterscheidung neoplastischer zystischer Läsionen von nichtneoplastischen Zysten, wobei erstere weiter in seröse und muzinöse Neoplasien unterteilt werden, die wiederum ein unterschiedliches Malignitätspotenzial aufweisen. Die Differenzialdiagnose kann schwierig sein und beinhaltet eine genaue Anamnese, eine differenzierte bildgebende Diagnostik sowie pathologische und laborchemische Analysen. Die häufigsten neoplastischen Läsionen sind inzwischen die IPMN. Sie haben immer eine Gangkommunikation und können in Hauptgang- IPMN mit schlechterer Prognose und Seitengang- IPMN mit besserer, allerdings subtypabhängiger variabler Prognose eingeteilt werden. Die Seitengang- IPMN bedürfen einer genauen Risikoeinschätzung, die u. a. von Zystencharakteristika wie dem histologischen Subtyp und Risikofaktoren wie Größe, soliden Anteilen und Gangdilatation abhängt. Während unspezifische abdominelle Beschwerden keinen diagnostischen Wert haben, sind Gewichtsverlust, Ikterus, neu diagnostizierter Diabetes mellitus und erhöhte CA19-9- Werte im Serum Warnsymptome für eine maligne Entartung. Die Hauptgang-IPMN und geringer die MCN haben das größte Malignitätspotenzial der muzinösen Neoplasien und sollten wie die SPN immer reseziert werden, während SCN eine sehr geringes Malignitätspotenzial aufweisen. Kleinere Seitengang-IPMN und SCN k

  9. Buchbesprechungen und neuere Testverfahren

    OpenAIRE

    2006-01-01

    Buchbesprechungen: Siegler, R.; DeLoache, J.; Eisenberg, N. (2005): Entwicklungspsychologie im Kindes- und Jugendalter, herausgegeben von S. Pauen. Heidelberg. Dammasch, F.; Metzger, H.-G. (Hg.) (2005): Die Bedeutung des Vaters. Psychoanalytische Perspektiven. Frankfurt a. M.. Jacobs, C.; Petermann, F. (2005): Diagnostik von Rechenstörungen. Göttingen. Katz-Bernstein, N. (2005): Selektiver Mutismus bei Kindern. Erscheinungsbilder, Diagnostik, Therapie. München. Wirschi...

  10. Fungal/bacterial interactions during the biodegradation of TEX hydrocarbons (toluene, ethylbenzene and p-xylene) in gas biofilters operated under xerophilic conditions

    NARCIS (Netherlands)

    Prenafeta-Boldu, F.X.; Guivernau, M.; Gallastegui, G.; Vinas, M.; de Hoog, G.S.; Elias, A.

    2012-01-01

    The treatment of air contaminated with toluene, ethylbenzene, and p-xylene was assayed in three laboratory-scale biofilters, each consisting of two modules connected in series, packed with a pelletized organic fertilizer and inoculated with a toluene-degrading liquid enrichment culture. Biofilters w

  11. Einleitung: Kindheit und Gerechtigkeit

    Directory of Open Access Journals (Sweden)

    Graf Gunter

    2015-07-01

    Full Text Available Beschäftigt man sich systematisch mit der Konzeption von Gerechtigkeit für Kinder bzw. während der Kindheit, ist es hilfreich, drei verschiedene Fragen zu klären, die normalerweise in Hinblick auf Erwachsene diskutiert werden, doch auch für eine genauere Analyse der Ansprüche von Kindern relevant sind. Welche Güter sind für die Gerechtigkeitstheorie relevant? Nach welchen Prinzipien sollen diese Güter verteilt werden? Wer ist dafür verantwortlich, dass die angestrebte Güterverteilung verwirklicht wird? In dieser Einleitung umreißen wir kurz den gegenwärtigen Diskussionsstand, der in diesen drei großen gerechtigkeitsrelevanten Themenfeldern hinsichtlich von Kindern besteht. Zunächst analysieren wir Ressourcen und Fähigkeiten (capabilities als angemessene Metrik der Gerechtigkeit für Kinder. Hinsichtlich der Verteilungsprinzipien lassen sich vor allem egalitäre und suffizienztheoretische Herangehensweisen unterscheiden. Schließlich werden in Bezug auf die Frage nach den relevanten „Akteuren der Gerechtigkeit“ für Kinder („agents of justice“ hauptsächlich die Familie bzw. die Eltern und der Staat diskutiert.

  12. Tools and data for the geochemical modeling. Thermodynamic data for sulfur species and background salts and tools for the uncertainty analysis; WEDA. Werkzeuge und Daten fuer die Geochemische Modellierung. Thermodynamische Daten fuer Schwefelspezies und Hintergrundsalze sowie Tools zur Unsicherheitsanalyse

    Energy Technology Data Exchange (ETDEWEB)

    Hagemann, Sven; Schoenwiese, Dagmar; Scharge, Tina

    2015-07-15

    The report on tools and data for the geochemical modeling covers the following issues: experimental methods and theoretical models, design of a thermodynamic model for reduced sulfur species, thermodynamic models for background salts, tools for the uncertainty and sensitivity analyses of geochemical equilibrium modeling.

  13. Performance comparison of low and high temperature polymer electrolyte membrane fuel cells. Experimental examinations, modelling and numerical simulation; Leistungsvergleich von Nieder- und Hochtemperatur-Polymerelektrolytmembran-Brennstoffzellen. Experimentelle Untersuchungen, Modellierung und numerische Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Loehn, Helmut

    2010-11-03

    The experimental part of this thesis essentially comprises the performance comparison of low temperature (LT) - polymer electrolyte membrane fuel cells (PEMFCs) on basis of Nafion {sup registered} and high temperature (HT)- PEMFCs on basis of Polybenzimidazol (PBI)/phosphoric acid (H{sub 3}PO{sub 4}). The performance characteristic of commercially available Nafion {sup registered} - LT - (E-TEK-Series 12 W) and PBI/H{sub 3}PO{sub 4} - HT -(Celtec P 1000) membrane electrode assemblies (MEAs) were examined with a single cell in dependence of cell temperature (LT-MEA: 50 - 80 C, HT-MEA: 120 - 190 C), anode and cathode pressure (1 - 3 bar), stoichiometry of gas supply streams and relative humidity (only LT-MEA). Because of the same active cell area of both MEAs (45.16 cm{sup 2}) and the fact, that the flow field for the gas distribution of the test cell can be used universally, the performance tests with both MEA-types could be carried out with the same single test cell. When comparing the performance of both MEAs under similar test conditions - except increased temperature and deactivated humidification of the HT-MEA - at 0.7 A/cm{sup 2} with both MEA-types nearly equal performance densities of 0.3 - 0.45 W/cm{sup 2} can be reached. Since there is no liquid process water present in the HT-MEA the operation is not limited by concentration losses; therefore the HT-MEA can be operated in a wider range with higher current densities and because of the not required water management the operation of the HT-MEA is essentially simplified. Further advantages of the HT-MEA exist in the relative high tolerance against the catalyst poison carbon monoxide - the operation with reformat gas and hydrogen rich gases is facilitated - and an improved heat management because of the elevated operation temperature. However, a disadvantage of the Celtec-P-1000-MEA exists in the degradation at deep temperatures. At operating conditions, in which liquid process water is present, there is the danger of washing out of the phosphoric acid. In an additional test row the Celtec-P-1000 HT-MEA was subjected to temperature change cycles (40 - 160 C), which lead to irreversible voltage losses. In a final test row performance tests were carried out with a HT-PEM fuel cell stack (16 cells /1 kW), developed in the fuel cell research centre of Volkswagen with a special gas diffusion electrode, which should avoid the degradation at deep temperatures. In these examinations no irreversible voltage losses could be detected, but the tests had to be aborted because of leakage problems. The by the experimental examinations gained insight of the superior operating behaviour and the further advantages of the HT-PEMFC in comparison to the LT-PEMFC were crucial for the construction of a simulation model for a single HT-PEM fuel cell in the theoretical part of this thesis, that also should be suitable as process simulation model for the computer based development of a virtual fuel cell within the interdisciplinary project ''Virtual Fuel Cell'' at the TU Darmstadt. The model is a numerical 2D ''along the channel'' - model, that was constructed with the finite element software COMSOL Multiphysics (version 3.5 a). The stationary, one phase model comprises altogether ten dependent variables in seven application modules in a highly complex, coupled non linear system of equations with 33713 degrees of freedom (1675 rectangle elements with 1768 nodes). The simulation model describes the mass transport processes and the electro-chemical reactions in a HT-PEM fuel cell with good accuracy, the model validation by comparing the model results with experimental data could be proved. So the 2D-model is basically suitable as process simulation model for the projecting of a virtual HT-PEM fuel cell. (orig.)

  14. Modelling and simulation of a circulating fluidized-bed steam generator as an aid for process analysis and automation. Modellierung und Simulation eines ZWS-Dampferzeugers als Hilfsmittel zur Prozessanalyse und -automatisierung

    Energy Technology Data Exchange (ETDEWEB)

    Karbach, A.; Peters, R.; Schaub, G. (Lurgi GmbH, Frankfurt am Main (Germany, F.R.))

    1990-04-01

    This book deals with the development and application of mathematical model for the simulation of a steam generator with fluidized-bed combustion (coal combustion in the circulating fluidized-bed combustion). (orig./EF).

  15. MODEL ADSORPSI LANGMUIR GAS DINITROGEN MONOKSIDA DALAM SISTEM BIOFILTER DENGAN MEDIUM PUPUK KOMPOS

    Directory of Open Access Journals (Sweden)

    Tania Surya Utami

    2012-04-01

    Full Text Available  LANGMUIR ADSORPTION MODEL FOR DINITROGEN MONOXIDE IN BIOFILTER SYSTEM USING COMPOST FERTILIZER MEDIUM. Nitrous oxide (N2O is mostly emitted from various industrial processes and agricultural activities. This gas causes serious environmental problems and is considered as a dangerous pollutant. In the past, traditional control technologies, such as Selective Catalytic Reduction (SCR and Selective Non-Catalytic Reduction (SNCR, were applied to control N2O emissions in some industries. However, these two processes required high temperatures and the use of catalysts. Economic and technical constraints in SCR and SNCR methods motivated researchers to develop new, cost-effective processes to remove N2O. Biofiltration is an emerging technology that offers a number of advantages over traditional methods of air pollution control. The purpose of this research is to modelise the biofiltration experimental results into the Langmuir adsorption model. This research is conducted in laboratory scale biofilter column, with parameters studied are effect of biofilter length and N2O gas flowrate. The result of the model is simulated into sensitivity analysis. The average Langmuir constant obtained in the model of the research is 16.006 liter/mol. Dinitrogen Monoksida (N2O merupakan emisi dari proses industri dan kegiatan pertanian. Gas tersebut merupakan gas polutan berbahaya dan menyebabkan masalah lingkungan yang serius. Sebelumnya, teknologi kontrol tradisional seperti Selective Catalytic Reduction (SCR dan Selective Non-Catalytic Reduction (SNCR digunakan untuk mengontrol emisi N2O pada kegiatan-kegiatan industri. Akan tetapi, kedua proses ini membutuhkan suhu yang tinggi dan penggunaan katalis. Adanya masalah dari segi ekonomi dan teknis memotivasi peneliti untuk mengembangkan teknologi baru yang lebih murah dan efisien untuk menghilangkan N2O dari gas buangan. Pengolahan N2O secara biologis dalam proses biofiltrasi adalah salah satu alternatif ramah

  16. Treatment of gaseous toluene in three biofilters inoculated with fungi/bacteria: Microbial analysis, performance and starvation response.

    Science.gov (United States)

    Cheng, Zhuowei; Lu, Lichao; Kennes, Christian; Yu, Jianming; Chen, Jianmeng

    2016-02-13

    Bacteria and fungi are often utilized for the biodegradation of organic pollutants. This study compared fungal and/or bacterial biofiltration in treating toluene under both steady and unsteady states. Fungal biofilter (F-BF) removed less toluene than both bacterial biofilters (B-BF) and fungal & bacterial biofilters (F&B-BF) (60% vs >90%). The mineralization ratio was also lower in F-BF-levels were 2/3 and 1/2 of those values obtained by the other biofilters. Microbial analysis showed that richer communities were present in B-BF and F&B-BF, and that the Hypocreales genus which Trichoderma viride belongs to was much better represented in F&B-BF. The F&B-BF also supported enhanced robustness after 15-day starvation episodes; 1 day later the performance recovered to 80% of the original removal level. The combination of bacteria and fungi makes biofiltration a good option for VOC treatment including better removal and performance stability versus individual biofilters (bacteria or fungi dominated).

  17. Anaerobic ammonium-oxidizing (anammox) bacteria and associated activity in fixed-film biofilters of a marine recirculating aquaculture system.

    Science.gov (United States)

    Tal, Yossi; Watts, Joy E M; Schreier, Harold J

    2006-04-01

    Microbial communities in the biological filter and waste sludge compartments of a marine recirculating aquaculture system were examined to determine the presence and activity of anaerobic ammonium-oxidizing (anammox) bacteria. Community DNA was extracted from aerobic and anaerobic fixed-film biofilters and the anaerobic sludge waste collection tank and was analyzed by amplifying 16S rRNA genes by PCR using anammox-selective and universal GC-clamped primers. Separation of amplified PCR products by denaturing gradient gel electrophoresis and sequencing of the different phylotypes revealed a diverse biofilter microbial community. While Planctomycetales were found in all three communities, the anaerobic denitrifying biofilters contained one clone that exhibited high levels of sequence similarity to known anammox bacteria. Fluorescence in situ hybridization studies using an anammox-specific probe confirmed the presence of anammox Planctomycetales in the microbial biofilm from the denitrifying biofilters, and anammox activity was observed in these biofilters, as detected by the ability to simultaneously consume ammonia and nitrite. To our knowledge, this is the first identification of anammox-related sequences in a marine recirculating aquaculture filtration system, and our findings provide a foundation for incorporating this important pathway for complete nitrogen removal in such systems.

  18. ...und Einstein hatte doch recht

    Science.gov (United States)

    Will, Clifford M.; Leuchs, Anne; Leuchs, Gerd

    Keine wissenschaftliche Theorie ist auf solche Faszination auch außerhalb der Wissenschaft gestoßen wie die Allgemeine Relativitätstheorie von Albert Einstein, und keine wurde so nachdrücklich mit den Mitteln der modernen Physik überprüft. Wie hat sie diesen Test mit Raumsonden, Radioastronomie, Atomuhren und Supercomputern standgehalten? Hatte Einstein recht? Mit der Autorität des Fachmanns und dem Flair des unvoreingenommenen Erzählers schildert Clifford Will die Menschen, Ideen und Maschinen hinter den Tests der allgemeinen Relativitätstheorie. Ohne Formeln und Fachjargon wird der leser mit Einsteins Gedanken vertraut und erfährt von der Bestätigung seiner Vorhersagen, angefangen bei der Lichtablenkung im Schwerefeld der Sonne 1919 bis zu den ausgefeilten Kreiselexperimenten auf dem Space Shuttle. Die Allgemeine Relativitätstheorie hat nich nur alle diese Tests bestanden, sie hat darüber hinaus wesentlich beigetragen zu unserem Verständnis von Phänomenen wie Pulsaren, Quasaren, Schwarzen Löchern und Gravitationslinsen. Dieses Buch erzählt lebendig und spannend die Geschichte einer der größten geistigen Leistungen unserer Zeit.

  19. Group-specific quantification of methanotrophs in landfill gas-purged laboratory biofilters by tyramide signal amplification-fluorescence in situ hybridization.

    Science.gov (United States)

    Wang, Hong; Einola, Juha; Heinonen, Mirja; Kulomaa, Markku; Rintala, Jukka

    2008-09-01

    The aim of this study was to quantitatively analyse methanotrophs in two laboratory landfill biofilters at different biofilter depths and at temperatures which mimicked the boreal climatic conditions. Both biofilters were dominated by type I methanotrophs. The biofilter depth profiles showed that type I methanotrophs occurred in the upper layer, where relatively high O(2) and low CH(4) concentrations were present, whereas type II methanotrophs were mostly distributed in the zone with high CH(4) and low O(2) concentrations. The number of type I methanotrophic cells declined when the temperature was raised from 15 degrees C to 23 degrees C, but increased when lowered to 5 degrees C. A slight decrease in type II methanotrophs was also observed when the temperature was raised from 15 degrees C to 23 degrees C, whereas cell numbers remained constant when lowered to 5 degrees C. The results indicated that low temperature conditions favored both type I and type II methanotrophs in the biofilters.

  20. Rudolf Streinz. Meinungs- und Informationsfreiheit zwischen Ost und West / Henn-Jüri Uibopuu

    Index Scriptorium Estoniae

    Uibopuu, Henn-Jüri, 1929-2012

    1983-01-01

    Tutvustus: Streinz, Rudolf. Meinungs- und Informationsfreiheit zwischen Ost und West : Möglichkeiten und Grenzen intersystemarer völkerrechtlicher Garantien in einem systemkonstituierenden Bereich. Ebelsbach : Rolf Gremer, 1981

  1. Bildanalyse in Medizin und Biologie

    Science.gov (United States)

    Athelogou, Maria; Schönmeyer, Ralf; Schmidt, Günther; Schäpe, Arno; Baatz, Martin; Binnig, Gerd

    Heutzutage sind bildgebende Verfahren aus medizinischen Untersuchungen nicht mehr wegzudenken. Diverse Methoden - basierend auf dem Einsatz von Ultraschallwellen, Röntgenstrahlung, Magnetfeldern oder Lichtstrahlen - werden dabei spezifisch eingesetzt und liefern umfangreiches Datenmaterial über den Körper und sein Inneres. Anhand von Mikroskopieaufnahmen aus Biopsien können darüber hinaus Daten über die morphologische Eigenschaften von Körpergeweben gewonnen werden. Aus der Analyse all dieser unterschiedlichen Arten von Informationen und unter Konsultation weiterer klinischer Untersuchungen aus diversen medizinischen Disziplinen kann unter Berücksichtigung von Anamnesedaten ein "Gesamtbild“ des Gesundheitszustands eines Patienten erstellt werden. Durch die Flut der erzeugten Bilddaten kommt der Bildverarbeitung im Allgemeinen und der Bildanalyse im Besonderen eine immer wichtigere Rolle zu. Gerade im Bereich der Diagnoseunterstützung, der Therapieplanung und der bildgeführten Chirurgie bilden sie Schlüsseltechnologien, die den Forschritt nicht nur auf diesen Gebieten maßgeblich vorantreiben.

  2. Zeitschriftenübersicht und Buchbesprechungen

    OpenAIRE

    1993-01-01

    Zeitschriftenübersicht und Buchbesprechungen: de Shazer, S. (1991): Putting Difference to Work. New York. Schaffer, M. R. (1992): ... und was geschieht mit den Kindern? Bern. Ludewig, K. (1992): Systemische Therapie. Grundlagen klinischer Theorie und Praxis. Stuttgart. Eickhoff, F.-W./Loch, W. (Hrsg) (1992): Jahrbuch der Psychoanalyse - Beitrage zur Theorie und Praxis, Bd. 29. Stuttgart. Wiesse, J. (Hrsg) (1992): Chaos und Regel. Die Psychoanalyse in ihren Institutionen. G...

  3. Antibiotikafreisetzung und Klebefestigkeit modifizierter PMMA Knochenzemente

    OpenAIRE

    Weckwerth, Felix

    2009-01-01

    Im Rahmen dieser Arbeit wurden zwei modifizierte Knochenzemente auf ihre Klebefestigkeit und Antibiotikafreisetzung untersucht und mit dem herkömmlichen Biomet Bone Cement verglichen. Beiden Modifikationen wurde Hydroxyethylmethacrylat-Phosphat (HEMA-P) untergemischt. Die eine Modifikation war zusätzlich mit Natriumcarbonat und Calciumchlorid beladen. Der mit HEMA-P, Natriumcarbonat und Calciumchlorid modifizierte Knochenzement erreichte initial lediglich 85 Prozent der Zug- und 81 Prozent de...

  4. Wirksamkeit von impliziten und expliziten Lernprozessen : Aneignung taktischer Kompetenzen und motorischer Fertigkeiten im Basketball

    OpenAIRE

    Calábria Lopes, Mariana

    2011-01-01

    Das Hauptziel der vorliegenden Studie war die Untersuchung der Frage, welche Effekte implizite und explizite Lernprozesse und eine Kombination aus beiden auf technische Fertigkeiten und taktische Kompetenzen von Anfängern im Basketball haben. Zur Überprüfung dieser Fragestellung wurden 86 Probanden zwischen 9 und 12 Jahre in drei Interventionsgruppen (explizite, implizite und implizit-explizite Gruppe) und eine Kontrollgruppe aufgeteilt, die in einem Messwiederholungsdesign getestet wurden. D...

  5. [Die baltischen Lande im Zeitalter der Reformation und Konfessionalisierung. Livland, Estland, Ösel, Ingermanland, Kurland und Letgallen. Stadt, Land und Konfession 1500-1721. 2. und 3. Teil] / Anti Selart

    Index Scriptorium Estoniae

    Selart, Anti, 1973-

    2012-01-01

    Arvustus: Die baltischen Lande im Zeitalter der Reformation und Konfessionalisierung. Livland, Estland, Ösel, Ingermanland, Kurland und Letgallen. Stadt, Land und Konfession 1500-1721. Hrsg. von Matthias Asche, Werner Buchholz, Anton Schindling. 2. und 3. Teil.

  6. Diversity of Nitrate-Reducing and Denitrifying Bacteria in a Marine Aquaculture Biofilter and their Response to Sulfide

    DEFF Research Database (Denmark)

    Krieger, Bärbel; Schwermer, Carsten U.; Rezakhani, Nastaran;

    2006-01-01

    DIVERSITY OF NITRATE-REDUCING AND DENITRIFYING BACTERIA IN A MARINE AQUACULTURE BIOFILTER AND THEIR RESPONSE TO SULFIDE B.U. Krieger 1,5, C. Schwermer 2, N. Rezakhani 5, M.A. Horn 1, A. Gieseke 2, E. Cytryn 3, D. Minz 3, J. van Rijn 4, H.L. Drake 1, A. Schramm 5 1 Dept. of Ecological Microbiology...... was developed containing a 3-stage biofilter for nitrification, denitrification/anaerobic sludge digestion, and sulfide oxidation. Sulfate reduction in the anaerobic part of the system leads to sulfide concentrations exceeding 5 mM, which may affect nitrate reduction and denitrification. Sulfide can inhibit...... nitrous oxide reductase, trigger a shift from denitrification to dissimilatory nitrate reduction to ammonium (DNRA), or be used as electron donor for nitrate reduction. The goal of this study was to identify and isolate nitrate-reducing and denitrifying bacteria from the biofilter and to investigate...

  7. Impact of water boundary layer diffusion on the nitrification rate of submerged biofilter elements from a recirculating aquaculture system

    DEFF Research Database (Denmark)

    Prehn, Jonas; Waul, Christopher Kevin; Pedersen, Lars-Flemming

    2012-01-01

    Total ammonia nitrogen (TAN) removal by microbial nitrification is an essential process in recirculating aquaculture systems (RAS). In order to protect the aquatic environment and fish health, it is important to be able to predict the nitrification rates in RAS’s. The aim of this study...... was to determine the impact of hydraulic film diffusion on the nitrification rate in a submerged biofilter. Using an experimental batch reactor setup with recirculation, active nitrifying biofilter units from a RAS were exposed to a range of hydraulic flow velocities. Corresponding nitrification rates were...... measured following ammonium chloride, NH4Cl, spikes and the impact of hydraulic film diffusion was quantified. The nitrification performance of the tested biofilter could be significantly increased by increasing the hydraulic flow velocity in the filter. Area based first order nitrification rate constants...

  8. Evaluation of a biofilter deliberately inoculated with bacteria capable of removing specific kraft pulp mill air emission components

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, R.N.; Dombroski, E.C. [Microbiology Research and Development, Vegreville (Canada)

    1995-12-31

    A biofilter inoculated with Thiobacillus thiooxidans was used to treat Kraft pulp mill green liquor clarifier emissions, which typically contain hydrogen sulphide (H{sub 2}S), dimethyl sulphide (DMS), methyl mercaptan, and dimethyl disulphide. Results from lab-scale and demonstration-scale trials indicate that biofilters inoculated with bacteria capable of oxidizing reduced sulphur compounds have been extremely successful in removing relatively high concentrations of H{sub 2}S. Less successful results were observed with respect to the oxidation of DMS, possibly due to this compound having a relatively low solubility in water. Preliminary results from the demonstration-scale biofilter indicate that H{sub 2}S, DMS and other compounds are removed from green liquor emissions. The variable results are primarily due to erratic temperature fluctuations and the presence of alkaline substances in the gas stream.

  9. 陶瓷球填料生物滴滤塔降解甲苯废气%PURIFYING WASTE GAS CONTAINING LOW CONCENTRATION TOLUENE IN TRICKLING BIOFILTER WITH CERAMIC SPHERES

    Institute of Scientific and Technical Information of China (English)

    廖强; 田鑫; 朱恂; 王永忠; 陈蓉; 廖浩

    2003-01-01

    The Purification experiments of waste gas containing low concentration toluene were made in trickling biofilter with ceramic spheres. The effects of liquid flow rate,gas flow rate,pH of circulation liquid, and toluene concentration in inlet gas on the purification efficiency of trickling biofilter were investigated. The pressure drop of the trickling biofilter was also measured during experiments.Increasing liquid flow rate and gas flow rate resulted in the decrease of purification efficiency of trickling biofilter. The highest purification efficiency of trickling biofilter was found at the circulation liquid pH of 7. The porosity of the packing material at the inlet of gas was higher than that at the outlet of gas in biofilter after continuous operation in 50 days. The decrease in the porosity of packing material caused a great increase in the pressure drop of the biofilter.

  10. Hypophosphatasie - aktuelle Diagnostik und Therapie

    Directory of Open Access Journals (Sweden)

    BeckC

    2009-01-01

    Full Text Available Die Hypophosphatasie (HP ist eine seltene, autosomal rezessiv vererbte Erkrankung des Knochenstoffwechsels mit verminderter Aktivität der gewebeunspezifischen alkalischen Phosphatase (TNSAP und Akkumulation von nicht abgebauten Stoffwechselprodukten. Sie ist charakterisiert durch eine generelle Störung der Knochenmineralisation mit nachfolgenden Knochendeformitäten, Frakturen oder auch chronischer nicht bakterieller Osteomyelitis. Nierenbeteiligung mit Nephrokalzinose, Zahnveränderungen bzw. vorzeitiger Zahnverlust, des weiteren Kraniosynostosen sind bekannt. Kürzlich konnten wir zeigen, dass der klinische Phänotyp der infantil-juvenilen Form unter anderem durch Entzündung von Gelenken und Knochen beeinflusst wird. Der genaue Pathomechanismus, der zur Zellaktivierung mit resultierender Knochenentzündung und Gewebsdestruktion führt, ist noch nicht endgültig geklärt. Nach dem aktuellen Stand der Forschung scheinen akkumulierende Kalziumpyrophosphatkristalle, die zur Aktivierung von Rezeptoren des angeborenen Immunsystems und nachfolgend verschiedener komplexer inflammatorischer Signalkaskaden führen, hierbei eine entscheidende Rolle zu spielen. Die Diagnosesicherung erfolgt mithilfe laborchemischer Analysen, genetischer Testung und radiologischer Bildgebung. Gerade aufgrund der Vielseitigkeit der möglichen klinischen Symptome ist eine enge Anbindung an ein mit HP-Patienten erfahrenes Zentrum mit multidisziplinärer Betreuung (Pädiatrie, Radiologie, Orthopädie, Neurochirurgie, Kieferorthopädie und Parodontologie, desweiteren Physiotherapie und Ernährungsberatung von entscheidender Bedeutung. Da derzeit kurative Therapien, z. B. eine Enzymersatztherapie, noch nicht evaluiert sind, stehen aktuell symptomatische Therapieansätze im Vordergrund der Behandlung.

  11. GROSSSPRENGUN UND MIKROSEISMIK

    Directory of Open Access Journals (Sweden)

    E. HARDTWIG

    1956-06-01

    Full Text Available Uéber die bei Sprengungen entstelienden Periodenspektren ist noch
    wenig bekannt, trotzdem in jedem Jahre Tausende von Sprengungen
    registriert werden. Die wenigen Arbeiten, die zu diesem Gegenstand erscliienen
    sind, stellen nur erste Versuche dar, den Aufbau der Spektren
    zu erklaren. Wàhrend etwa George Morris (* vorwiegend die bei
    Sprengungen si eh abspielenden Detonationsvorgànge zum Ausgangspunkt
    der Untersuchung macht, ist es bei IT. Menzel (2 die Interferenz von
    Primàrwelle und reflektierter Welle, deren Einfluss auf die Gestalt
    des Spektrums untersucht wird.

  12. Stalking: Klinische und forensische Bedeutung

    Directory of Open Access Journals (Sweden)

    Dreßing H

    2008-01-01

    Full Text Available Stalking ist in der Bevölkerung von Industrienationen ein weit verbreitetes Phänomen. Die Lebenszeitprävalenz beträgt über 11 %. Hinter den relativ gleichförmig erscheinenden Stalkingverhaltensweisen lassen sich unterschiedliche Täter-Opfer-Beziehungen und Motivationsstrukturen nachweisen. In der vorliegenden Arbeit werden wesentliche Aspekte der Tätertypologie sowie der psychischen Auswirkungen auf die Opfer diskutiert, sowie sich daraus ableitende und bisher noch kaum wahrgenommene Aufgaben der klinischen und forensischen Psychiatrie benannt. Da die Versorgung der Stalking-Opfer dringend verbessert werden muss, wird exemplarisch das Mannheimer Modellprojekt Stopp Stalking (MMSS vorgestellt.

  13. Implantation und Komplikation der Vagusnervstimulation

    Directory of Open Access Journals (Sweden)

    Spuck S

    2007-01-01

    Full Text Available Weltweit wurden bis zum Beginn des Jahres 2007 45.000 Vagusnervstimulatoren (VNS implantiert. Trotz der häufigen Operationen sind nur wenige Berichte über Komplikationen veröffentlicht. Die primäre operative Implantation ist ein sicheres Verfahren. Komplikationen und Nebenwirkungen können nach operations-, material- und stimulationsassoziiertem Ursprung unterteilt werden. Erforderliche Revisionseingriffe sind insbesondere bei Kindern anspruchsvoll. Im folgenden Artikel werden mögliche Probleme der VNS-Therapie und deren Behandlung dargestellt.

  14. Numerical simulation for volatile organic compound removal in rotating drum biofilter

    Institute of Scientific and Technical Information of China (English)

    CHEN Hong; YANG ChunPing; ZENG GuangMing; YU KongLiang; QU Wei; YU GuanLong; MENG Lei

    2007-01-01

    Rotating drum biofilters (RDBs) could effectively remove volatile organic compounds (VOCs) from waste gas streams.A mathematical model was developed on the basis of mass transport and mass balance equations in an RDB, the two-film theory, and the Monod kinetics.This model took account of mass transfer and biodegradation of VOC in the gas-water-biofilm three-phase system in the biofilter, and could simulate variations of VOC removal efficiency with a changing specific surface area and porosity of the media due to the increasing of biofilm thickness in the biofilter.Toluene was used as a model VOC.This model was further simplified by introducing a coefficient of the gas velocity and neglecting the water phase due to the complexity of operating conditions.The equations for the biofilm phase, gas phase, and biofilm accumulation in this model were solved using collocation method, analytic method, and the Runge-Kutta method separately.A computer program was written down as MATLAB to solve this model.Results of numerical solutions showed that toluene removal efficiency in the RDB increased and reached the maximum values of 97% on day 4 after the startup, and then decreased and remained at 90% after 5 more days of operation.Toluene concentration was high at the outermost layer where more than 70% toluene was removed, and was low at the innermost layer where less than 10% toluene was removed.The dynamic removal efficiencies from this model correlated reasonably well with experimental results for toluene removal in a multi-layered RDB.

  15. Environmental assessment of different biofilters for the treatment of gaseous streams.

    Science.gov (United States)

    Alfonsín, Carolina; Hernández, Jerónimo; Omil, Francisco; Prado, Óscar J; Gabriel, David; Feijoo, Gumersindo; Moreira, Ma Teresa

    2013-11-15

    Biological techniques have been considered as an interesting alternative to treat gaseous streams from industrial processes. In this work, the performance of biofilters was evaluated from an environmental point of view by using Life Cycle Assessment methodology. More specifically, the potential impacts of four biofilters packed with different organic materials: spherical clay pellets covered with compost, a mixture of coconut fibre and sludge based carbon, peat and heather and pine bark have been quantified. The impact categories considered in this work were: eutrophication, acidification, global warming, photochemical oxidation, malodorous air, human toxicity and marine, terrestrial and freshwater ecotoxicity. From an environmental point of view, the reactor packed with coconut fibre and sludge based carbon appears to be the most suitable alternative since it presented the lowest values in almost all the impact categories assessed. On the other hand, the biofilter packed with clay pellets covered with compost seems to be the most penalized bioreactor providing the highest impacts for six of the nine impact categories evaluated, mainly due to the significant pressure drop achieved in the reactor which led to a considerable increase of energy demand. The reactor packed with coconut fibre and sludge based carbon is also the most beneficial alternative after performing the normalization step. In this case, the alternatives of peat and heather and pine bark are the less favourable ones in terms of photochemical oxidation, which was attributed to the lowest efficiency of methyl isobutyl ketone removal efficiency observed in both configurations. On the other hand, the option of treating off-gases is, in general, more positive and advisable than the direct discharge to the atmosphere.

  16. Removal of p-xylene from an air stream in a hybrid biofilter

    Energy Technology Data Exchange (ETDEWEB)

    Wu Dan [School of Environmental and Biological Science and Technology, Dalian University of Technology No. 2, Linggong Road, Dalian, Liaoning Province 116023 (China); Quan Xie [School of Environmental and Biological Science and Technology, Dalian University of Technology No. 2, Linggong Road, Dalian, Liaoning Province 116023 (China)]. E-mail: quanxie@dlut.edu.cn; Zhao Yazhi [School of Environmental and Biological Science and Technology, Dalian University of Technology No. 2, Linggong Road, Dalian, Liaoning Province 116023 (China); Chen Shuo [School of Environmental and Biological Science and Technology, Dalian University of Technology No. 2, Linggong Road, Dalian, Liaoning Province 116023 (China)

    2006-08-21

    Biofiltration of an air stream containing p-xylene has been studied in a laboratory hybrid biofilter packed with a mixture of mature pig compost, forest soil and the packing material which was made of polyethylene (PE) and used in the moving bed biological reactor (MBBR) in wastewater treatment. Three flow rates, 9.17, 19.87 and 40.66m{sup 3}m{sup -2}h{sup -1}, were investigated for p-xylene inlet concentration ranging from 0.1 to 3.3gm{sup -3}. A high elimination capacity of 80gm{sup -3}h{sup -1} corresponding to removal efficiency of 96% was obtained at a flow rate of 9.17m{sup 3}m{sup -2}h{sup -1} (empty bed residence time of 132s). At a flow rate of 40.66m{sup 3}m{sup -2}h{sup -1} (empty bed residence time of 30s), the maximum elimination capacity for p-xylene was 40gm{sup -3}h{sup -1} and removal efficiencies were in the range of 47-100%. The production of carbon dioxide (P{sub CO{sub 2}}) is proportional to elimination capacity (EC) and the linear relation was formulated as P{sub CO{sub 2}}=1.65EC+15.58. Stable pH values ranging from 6.3 to 7.6 and low pressure drop values less than 0.2cm H{sub 2}O (19.6Pa) of packing media in compost-based biofilter of hybrid biofilter were observed, which avoided acidification and compaction of packing media and sustained the activity of microorganism populations.

  17. BIOFILTER AS A FUNCTIONAL ANNOTATION PIPELINE FOR COMMON AND RARE COPY NUMBER BURDEN.

    Science.gov (United States)

    Kim, Dokyoon; Lucas, Anastasia; Glessner, Joseph; Verma, Shefali S; Bradford, Yuki; Li, Ruowang; Frase, Alex T; Hakonarson, Hakon; Peissig, Peggy; Brilliant, Murray; Ritchie, Marylyn D

    2016-01-01

    Recent studies on copy number variation (CNV) have suggested that an increasing burden of CNVs is associated with susceptibility or resistance to disease. A large number of genes or genomic loci contribute to complex diseases such as autism. Thus, total genomic copy number burden, as an accumulation of copy number change, is a meaningful measure of genomic instability to identify the association between global genetic effects and phenotypes of interest. However, no systematic annotation pipeline has been developed to interpret biological meaning based on the accumulation of copy number change across the genome associated with a phenotype of interest. In this study, we develop a comprehensive and systematic pipeline for annotating copy number variants into genes/genomic regions and subsequently pathways and other gene groups using Biofilter - a bioinformatics tool that aggregates over a dozen publicly available databases of prior biological knowledge. Next we conduct enrichment tests of biologically defined groupings of CNVs including genes, pathways, Gene Ontology, or protein families. We applied the proposed pipeline to a CNV dataset from the Marshfield Clinic Personalized Medicine Research Project (PMRP) in a quantitative trait phenotype derived from the electronic health record - total cholesterol. We identified several significant pathways such as toll-like receptor signaling pathway and hepatitis C pathway, gene ontologies (GOs) of nucleoside triphosphatase activity (NTPase) and response to virus, and protein families such as cell morphogenesis that are associated with the total cholesterol phenotype based on CNV profiles (permutation p-value pipeline could improve the interpretability of copy number burden analysis where hundreds of loci or genes contribute toward disease susceptibility via biological knowledge groups such as pathways. This CNV annotation pipeline with Biofilter can be used for CNV data from any genotyping or sequencing platform and to

  18. Performance of different biofilters in a recirculating system for rainbow trout farming

    Directory of Open Access Journals (Sweden)

    Iván Sánchez O

    2016-05-01

    Full Text Available Objective. To evaluate the performance of different biofilters in a recirculating aquaculture system (RAS for trout farming. Materials and methods. It was used a 1m3 plastic tank for fries farming; fabric bags to solids retention; a submersible pump; a constant water level and flow distribution box; six up flow biofilters in 3” PVC tube; sand of D10=0.45mm as carrier. The reactors were operated at local temperature and with hydraulic retention time (HRT of 11 min, the biofilters were inoculated in the next way: R1-Control: RAS water; R2-Fish culture farm sludges; R3- Water from aerated lagoon of Antanas landfill (AL; R4-Aquarium sediments; R5- Aerated lagoon of AL sludges; R6-Sludges from sulfidogenic reactor of AL. The weight gain (WG and the food conversion (FC were evaluated, some physic-chemical parameters were monitored and the nitrogen and suspended solids removal efficiency were evaluated. Results. The WG of the cultured animals was 1.58 g/d and the FC was 1.41. There were no differences for ammonium and nitrite removal between the reactors; the average removal efficiencies were: ammonium 4.78%, nitrite 27.2%, nitrate 32.3%, suspended solids 37.5%; R4 and R5 reactors presented the best performance on nitrate removal, with average efficiencies of 47.4% and 42.8%. R3 presented the best SS removal with an average of 58.2%. Conclusions. The RAS water treatment system guaranteed appropriated liquid quality conditions for trout farming; the most efficient reactor for removal of the different forms of nitrogen was the inoculated with the aerated lagoon of AL sludges.

  19. A Comparative Study of Physical and Chemical Processes for Removal of Biomass in Biofilters

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Mendoza-Pérez

    2011-08-01

    Full Text Available After 6 months of operation a long-term biofilter was stopped for two weeks and then it was started up again for a second experimental period of almost 1.3 years, with high toluene loads and submitted to several physical and chemical treatments in order to remove excess biomass that could affect the reactor’s performance due to clogging, whose main effect is a high pressure drop. Elimination capacity and removal efficiency were determined after each treatment. The methods applied were: filling with water and draining, backwashing, and air sparging. Different flows and temperatures (20, 30, 45 and 60 °C were applied, either with distilled water or with different chemicals in aqueous solutions. Treatments with chemicals caused a decrease of the biofilter performance, requiring periods of 1 to 2 weeks to recover previous values. The results indicate that air sparging with pure distilled water as well as with solutions of NaOH (0.01% w/v and NaOCl (0.01% w/v were the treatments that removed more biomass, working either at 20, 30 or 45 °C and at relatively low flow rates (below 320 L h−1, but with a high biodegradation inhibition after the treatments. Dry biomass (g VS content was determined at three different heights of the biofilter in order to carry out each experiment under the same conditions. The same amount of dry biomass when applying a treatment was established so it could be considered that the biofilm conditions were identical. Wet biomass was used as a control of the biofilter’s water content during treatments. Several batch assays were performed to support and quantify the observed inhibitory effects of the different chemicals and temperatures applied.

  20. ANALISIS FISIS MEMBRAN BIOFILTER ASAP ROKOK BERBAHAN BIJI KURMA UNTUK MENANGKAP RADIKAL BEBAS

    Directory of Open Access Journals (Sweden)

    Bilkis Rizqiyah

    2014-10-01

    Full Text Available Rokok kretek merupakan salah satu produk budaya yang berurat akar pada kearifan lokal bangsa Indonesia. Merokok yang awalnya merupakan perlengkapan upacara adat telah bergeser menjadi kebiasaan umum dikalangan warga. Namun hingga saat ini isu pro-kontra rokok masih menjadi perbincangan hangat dikalangan masyarakat. Rokok yang terbuat dari tembakau jika dibakar akan menghasilkan beberapa reaksi kimia. Reaksi penguapan nikotin dan reaksi penguapan air. Nikotin yang menguap akan mengalami kondensasi kembali dalam paru-paru sehingga terjadi deposit nikotin yang menyebabkan penyakit kanker. Di sisi lain industri rokok yang berpijak pada kearifan lokal, mampu menjaga stabilitas perekonomian negara lewat sumbangsihnya dalam berbagai sektor salah satunya adalah Ekonomi. Komposit didefinisikan sebagai suatu sistem material yang tersusun dari campuran/kombinasi dua atau lebih unsur-unsur utama yang secara makro berbeda bentuk dan komposisi material namun tidak dapat dipisahkan. Biofilter komposit merupakan campuran dari beberapa bahan yang berasal dari alam dan diolah menjadi material komposit yang bertujuan untuk menyerap dan menghilangkan partikel radikal bebas yang terdapat di lingkungan. Kurma merupakan salah satu buah yang banyak dimanfaatkan dalam kedokteran ala nabi. Biji kurma mengandung senyawa-senyawa penting salah satunya fenolik bioaktif yang merupakan anti oksidan bagi makhluk hidup. Pada penelitian ini serbuk biji kuma digunakan sebagai membran komposit yang mampu menangkap beberapa jenis radikal bebas dari asap rokok. Pembuatan membran menggunakan biji kurma sebagai filler dengan variasi matriks PEG dan putuh telur. Variasi komposisi yang digunakan adalah 0.7 gram, 0.8 gram, 0.9 gram dan 1 gram filler dengan 0.3 ml PEG dan putih telur. Hasil menunjukkan bahwa pada komposisi yang sama membran komposit biofilter berbahan biji kurma dengan matriks PEG memiliki kemampuan menangkap lima radikal bebas yaitu Hidroperoxida, CO2-, C, Peroxy, O-2, Cu

  1. H2S removal and bacterial structure along a full-scale biofilter bed packed with polyurethane foam in a landfill site.

    Science.gov (United States)

    Li, Lin; Han, Yunping; Yan, Xu; Liu, Junxin

    2013-11-01

    Hydrogen sulfide accumulated under a cover film in a landfill site was treated for 7 months by a full-scale biofilter packed with polyurethane foam cubes. Sampling ports were set along the biofilter bed to investigate H2S removal and microbial characteristics in the biofilter. The H2S was removed effectively by the biofilter, and over 90% removal efficiency was achieved in steady state. Average elimination capacity of H2S was 2.21 g m(-3) h(-1) in lower part (LPB) and 0.41 g m(-3) h(-1) in upper part (UPB) of the biofilter. Most H2S was eliminated in LPB. H2S concentration varied along the polyurethane foam packed bed, the structure of the bacterial communities showed spatial variation in the biofilter, and H2S removal as well as products distribution changed accordingly. The introduction of odorants into the biofilter shifted the distribution of the existing microbial populations toward a specific culture that could metabolize the target odors.

  2. Monitoring und Evaluation von Clustern, Clusterinitiativen und Clusterpolitik

    OpenAIRE

    Genosko, Joachim; Walter, Sieglinde Amelia

    2009-01-01

    Das Clusterkonzept wird derzeit von der Politik mit dem Ziel eingesetzt, die regionale Wettbewerbsfähigkeit und Innovationskraft zu steigern. Das zentrale Ordnungsprinzip eines Clusters ist das Netzwerk. Unternehmen gleicher bzw. verwandter Branchen werden mit einschlägigen wissenschaftlichen Einrichtungen sowie staatlichen und kommunalen Behörden vernetzt. Raumrelevant werden Cluster dann, wenn sie eine regionale Dimension einnehmen. Raumplanerisch sind Cluster dabei ambivalent: Einerseits m...

  3. Etablierung und Charakterisierung einer Kokultur equiner endometrialer Epithel- und Stromazellen

    OpenAIRE

    2016-01-01

    Ziel dieser Studie war die Etablierung einer Kokultur aus equinen endometrialen Epithel- und Stromazellen. Nach der erfolgreichen Umsetzung des Kokulturmodells sollte im weiteren Versuchsablauf durch die Zugabe von 17β-Östradiol (E2) und/oder Progesteron (P4) zum Nährmedium der Einfluss der Hormone auf die Zellen untersucht werden. Neben einer lichtmikroskopischen Auswertung der zytomorphologischen Charakteristika beider Zellarten sollte die Expression der Steroidhormonrezeptoren Östrogenr...

  4. Design, construction and operation of bio-filters for odour control sewage treatment plants

    Energy Technology Data Exchange (ETDEWEB)

    Eitner, D.; Gethke, H.G. (G+E Umwelttechnologie GmbH, Aachen (DE))

    1987-01-01

    It is known from waste water technology that the micro-organisms existing in a clarification plant under living conditions as optimal as possible, are capable of decomposing pollution in waste water. This knowledge has been used to search for low-cost waste air treatment technologies. Odour substances of a waste air are decomposed by microbial procedures. The possibility of biological waste air clarification by means of bio-filter plants or compost filter plants is discussed in this paper. There are indications of this technology as early as in the year 1928. Technical progress can be noted with this technology, as well.

  5. Use of planted biofilters in integrated recirculating aquaculture-hydroponics systems in the Mekong Delta, Vietnam

    DEFF Research Database (Denmark)

    Trang, N.T.D.; Brix, Hans

    2014-01-01

    The feasibility of using planted biofilters for purification of recirculated aquaculture water in the Mekong Delta of Vietnam was assessed. The plant trenches were able to clean tilapia aquaculture water and to maintain good water quality in the fish tanks without renewal of the water. NH4-N was ...... rates of 725 kg N and 234 kg P ha-1 year-1. This research demonstrates that integrated recirculating aquaculture-hydroponics (aquaponics) systems provide significant water savings and nutrient recycling as compared with traditional fish ponds. © 2012 John Wiley & Sons Ltd....

  6. Biofilter media gas pressure loss as related to media particle size and particle shape

    DEFF Research Database (Denmark)

    Pugliese, Lorenzo; Poulsen, Tjalfe G.; Røjgaard Andreasen, Rune

    2013-01-01

    Pressure loss (ΔP) is a key parameter for estimating biofilter energy consumption. Accurate predictions of ΔP as a function of air velocity (V) are therefore essential, to assess energy consumption and minimize operation costs. This paper investigates the combined impact of medium particle size...... and shape on the V - ΔP relationship. V - ΔP measurements were performed using three commercially available materials with different particle shapes: crushed granite (very angular particles), gravel (particles of intermediate roundness) and Leca® (almost spherical particles). A total of 21 different...

  7. Demographische Diskurse und Politiken aus Geschlechterperspektive

    Directory of Open Access Journals (Sweden)

    Diana Auth

    2007-07-01

    Full Text Available Der von Peter A. Berger und Heike Kahlert herausgegebene Sammelband umfasst Analysen, die sich aus Geschlechterperspektive mit dem demographischen Wandel im nationalen und internationalen Kontext beschäftigen. Durch seine ideologie- und herrschaftskritischen sowie empirisch fundierten Beiträge zum demographischen Wandel trägt das Buch zur Versachlichung der medial wie wissenschaftlich aufgeheizten Debatte bei. Die Autor/-innen widersprechen allesamt der Tendenz, soziale Probleme zu demographisieren, und fordern stattdessen eine stärkere Historisierung, Kontextualisierung und eine geschlechtssensible Analyse und Interpretation demographischer Entwicklungen.

  8. Renaturierung und Management von Heiden

    Science.gov (United States)

    Härdtle, Werner; Assmann, Thorsten; van Diggelen, Rudy; von Oheimb, Goddert

    Heiden zählen zu den ältesten und besonders reizvollen Kulturlandschaften Nordwesteuropas. Sie sind bezeichnend für nährstoffarme Böden in wintermilden Gebieten mit hohen Sommerniederschlägen. Während Heiden vor wenigen Jahrhunderten noch weit verbreitet und für manche Landschaften sogar prägend waren, hat sich ihr Areal heute auf wenige, meist in Naturschutzgebieten gelegene Restbestände verkleinert. Zu diesem Rückgang haben maßgeblich Änderungen der Landnutzung, aber auch Nährstoffeinträge aus umgebenden Agrarflächen und atmogene Depositionen beigetragen. In den meisten Ländern der Europäischen Union sind Heiden heute gesetzlich geschützte Ökosysteme, da diese, neben ihrem Erholungswert für den Menschen, Pflanzen- und Tierarten beherbergen, die außerhalb von Heiden nicht oder kaum überlebensfähig sind.

  9. Faszination Weltall. Sehen und Verstehen.

    Science.gov (United States)

    Humphrey, C.

    This book is a German translation, by T. Bührke, of the English original "The amateur astronomer's pathfinder" published in 1992. Contents: 1. Die Erde im Universum. 2. Der Nachthimmel. 3. Die Erforschung von Raum und Zeit.

  10. Editorial: Computerspiele und Videogames in formellen und informellen Bildungskontexten

    Directory of Open Access Journals (Sweden)

    Johannes Fromme

    2008-01-01

    Full Text Available Computer- und Videospiele sind heute ein selbstverständlicher Bestandteil der Lebenswelt vieler Kinder und Jugendlicher, aber auch von (jüngeren Erwachsenen, die mit diesen neuen Medien aufgewachsen sind. Lange Zeit haben elektronische Bildschirmspiele allenfalls sporadische Beachtung gefunden. Weder in der Medienforschung oder Medienpädagogik noch in der breiteren Öffentlichkeit waren sie ein Gegenstand von breiterem Interesse.* In den letzten knapp zehn Jahren sind Video- und Computerspiele allerdings zunehmend in den Fokus der Aufmerksamkeit gerückt. Dabei sind in der massenmedial vermittelten Öffentlichkeit vor allem Amokläufe in Schulen in einen direkten Zusammenhang mit den Vorlieben (der Täter für bestimmte Computerspiele gebracht worden. Die auch von prominenten Politikern aufgegriffene These lautete, dass gewalthaltige Spiele wie der First Person Shooter «Counterstrike» ein virtuelles Trainingsprogramm für das Töten und daher als wesentliche Ursache solcher Schulmassaker anzusehen seien. Auf der Basis dieser kausalen Wirkungsannahmen bzw. der unterstellten negativen Lern- und Trainingseffekte werden seither immer wieder Forderungen nach einem Verbot solcher «Killerspiele» oder gar nach der Verbannung aller Bildschirmmedien aus den Kinderzimmern abgeleitet. Neben solcher skandalisierter Thematisierung ist aber zunehmend auch eine nüchterne wissenschaftliche Auseinandersetzung zu konstatieren. So haben sich seit Beginn des neuen Jahrtausends die «digital game studies» als interdisziplinäres Forschungsfeld etabliert. Im Jahr 2000 wurde innerhalb der Gesellschaft für Medienwissenschaft z.B. die AG Games gebildet, die sich zu einem wichtigen deutschsprachigen Forum für die wissenschaftliche Beschäftigung mit Computerspielen entwickelt hat, und im Jahr 2002 entstand die internationale Digital Games Research Association (DiGRA, die im September 2009 ihre vierte grosse Konferenz nach 2003, 2005 und 2007 durchgeführt hat

  11. Irritation durch Waschen und Desinfizieren

    OpenAIRE

    Weimer, Caroline Maria

    2006-01-01

    Ziel dieser Studie war die Irritation der Haut, hervorgerufen durch alkoholische Desinfektionsmittel und das Detergens Natriumlaurylsulfat (0,5% NLS) in einem repetitiven Testdesign zu untersuchen. Mittels nicht invasiver Untersuchungsmethoden quantifizierten wir die irritativen Effekte von Sterillium®, 2-Propanol 45% v/v, 1-Propanol 30% v/v, welches die alkoholische Grundlage von Sterillium® darstellt sowie von Wasser und NLS 0,5...

  12. Review: Joachim R. Höflich (2003). Mensch, Computer und Kommunikation. Theoretische Verortungen und empirische Befunde

    OpenAIRE

    Schmidt, Jan

    2004-01-01

    Joachim R. HÖFLICH entwickelt eine Theorie der Institutionalisierung computervermittelter Kommunikation, die den Nutzer und seine Erwartungen in den Mittelpunkt stellt. Nutzungsepisoden richten sich demnach an "Computerrahmen" aus, die Regeln und Routinen enthalten, wann und in welcher Form ein Medium und seine Dienste zu verwenden ist. Je nach Verwendungszweck (Information, öffentliche Diskussion oder interpersonale Kommunikation) strukturieren unterschiedliche Erwartungen das Verhalten der ...

  13. Interconnectedness und digitale Texte

    Directory of Open Access Journals (Sweden)

    Detlev Doherr

    2013-04-01

    Full Text Available Zusammenfassung Die multimedialen Informationsdienste im Internet werden immer umfangreicher und umfassender, wobei auch die nur in gedruckter Form vorliegenden Dokumente von den Bibliotheken digitalisiert und ins Netz gestellt werden. Über Online-Dokumentenverwaltungen oder Suchmaschinen können diese Dokumente gefunden und dann in gängigen Formaten wie z.B. PDF bereitgestellt werden. Dieser Artikel beleuchtet die Funktionsweise der Humboldt Digital Library, die seit mehr als zehn Jahren Dokumente von Alexander von Humboldt in englischer Übersetzung im Web als HDL (Humboldt Digital Library kostenfrei zur Verfügung stellt. Anders als eine digitale Bibliothek werden dabei allerdings nicht nur digitalisierte Dokumente als Scan oder PDF bereitgestellt, sondern der Text als solcher und in vernetzter Form verfügbar gemacht. Das System gleicht damit eher einem Informationssystem als einer digitalen Bibliothek, was sich auch in den verfügbaren Funktionen zur Auffindung von Texten in unterschiedlichen Versionen und Übersetzungen, Vergleichen von Absätzen verschiedener Dokumente oder der Darstellung von Bilden in ihrem Kontext widerspiegelt. Die Entwicklung von dynamischen Hyperlinks auf der Basis der einzelnen Textabsätze der Humboldt‘schen Werke in Form von Media Assets ermöglicht eine Nutzung der Programmierschnittstelle von Google Maps zur geographischen wie auch textinhaltlichen Navigation. Über den Service einer digitalen Bibliothek hinausgehend, bietet die HDL den Prototypen eines mehrdimensionalen Informationssystems, das mit dynamischen Strukturen arbeitet und umfangreiche thematische Auswertungen und Vergleiche ermöglicht. Summary The multimedia information services on Internet are becoming more and more comprehensive, even the printed documents are digitized and republished as digital Web documents by the libraries. Those digital files can be found by search engines or management tools and provided as files in usual formats as

  14. Editorial: Neue Medien und individuelle Leistungsdarstellung: Möglichkeiten und Grenzen von ePortfolios und eAssessments

    OpenAIRE

    Claudia de Witt; Thomas Czerwionka

    2010-01-01

    Der Einsatz digitaler Medien in formellen Lernzusammenhängen (Schule, Hochschule, berufliche Bildung etc.) bietet neue Möglichkeiten, die Kenntnisse und Kompetenzen Lernender darzustellen bzw. abzubilden. So sollen z.B. Instrumente wie E-Portfolios eine selbstbestimmtere Leistungsdarstellung ermöglichen: Lernende sollen ihren Lernprozess dokumentieren und reflektieren, sich ihrer Verantwortung für ihn bewusst werden und ihn im Idealfall selbst steuern, Lehrende nehmen dabei eine beratende und...

  15. Characterisation of hexane-degrading microorganisms in a biofilter by stable isotope-based fatty acid analysis, FISH and cultivation.

    Science.gov (United States)

    Friedrich, Michèle M; Lipski, André

    2010-01-01

    The hexane-degrading bacterial community of a biofilter was characterised by a combination of stable isotope-based phospholipid fatty acid analyses, fluorescence in situ hybridisation and cultivation. About 70 bacterial strains were isolated from a full-scale biofilter used for treatment of hexane containing waste gas of an oil mill. The isolation approach led to 16 bacterial groups, which were identified as members of the Alpha-, Beta- and Gammaproteobacteria, Actinobacteria and Firmicutes. Three groups showed good growth on hexane as the sole source of carbon. These groups were allocated to the genera Gordonia and Sphingomonas and to the Nevskia-branch of the Gammaproteobacteria. Actively degrading populations in the filter material were characterised by incubation of filter material samples with deuterated hexane and subsequent phospholipid fatty acid analysis. Significant labelling of the fatty acids 16:1 cis10, 18:1 cis9 and 18:0 10methyl affiliated the hexane-degrading activity of the biofilter with the isolates of the genus Gordonia. In vitro growth on hexane and in situ labelling of characteristic fatty acids confirmed the central role of these organisms in the hexane degradation within the full-scale biofilter.

  16. Determination of the efficiency of sawdust and coco fiber used as Biofilter for pollutant removal for the treatment of wastewater

    Directory of Open Access Journals (Sweden)

    Jimmy Vicente Reyes

    2016-09-01

    Full Text Available Water is a resource used by mankind for industrial and domestic needs, which once used, is discharged into the public sewer system or septic tanks. This project proposes an ecological alternative for the treatment of wastewater from domestic use named Biofilter, which is built of living material (worms and inert material (chip and gravel, which filters the wastewater; the biological filter has shown high efficiency in the removal of organic matter and pathogens. The field work was carried out with experimental biological filters, to ascertain the best composition of inert material, different variants were used. Two experimental Biofilters, one using sawdust and the other coco fiber were used in the treatment of domestic wastewater; treated samples from each reactor were subjected to laboratory analysis. The analysis and interpretation of results showed that the Biofilter using sawdust removed 53.53 % of pollutants and is outside the required norm for wastewater treatment and the Biofilter using coco fiber removed 82.37 % of contaminants and is within the Environmental Quality Norm and Effluent Discharge: Water Resource.

  17. Inorganic nitrogen control in a novel zero-water exchanged aquaculture system integrated with airlift-submerged fibrous nitrifying biofilters.

    Science.gov (United States)

    Sesuk, Thanathon; Powtongsook, Sorawit; Nootong, Kasidit

    2009-03-01

    This work examined the feasibility of applying shrimp diets to establish nitrification on submerged fibrous biofilters. It also investigated the performance of a proposed zero-water exchanged aquaculture system, which integrated growing of aquatic stocks and operation of acclimated biofilters in the same environment. Addition of shrimp diets fully established nitrification within 3 weeks as indicated by continuous increase of nitrate and trivial levels of ammonium and nitrite. A series of batch experiment revealed an average ammonium degradation rate of 24.1mg Nm(-2) day(-1). Zero-water discharged tilapia cultivation could be carried out in the proposed aquaculture system for at least 44 days when daily inorganic loadings increased from 1.24 to 10.78mg Nl(-1) day(-1). The corresponding daily growth rates of tilapia from the proposed aquaculture systems integrated with acclimated biofilters varied from 3.01 to 3.35g day(-1), which was approximately 7-16% better than numbers from the systems using non-acclimated biofilters.

  18. Stabilization of Stormwater Biofilters: Impacts of Wetting and Drying Phases and the Addition of Organic Matter to Filter Media

    Science.gov (United States)

    Subramaniam, D. N.; Egodawatta, P.; Mather, P.; Rajapakse, J. P.

    2015-09-01

    Ripening period refers to a phase of stabilization in sand filters in water treatment systems that follow a new installation or cleaning of the filter. Intermittent wetting and drying, a unique property of stormwater biofilters, would similarly be subjected to a phase of stabilization. Suspended solids are an important parameter that is often used to monitor the stabilization of sand filters in water treatment systems. Stormwater biofilters, however, contain organic material that is added to the filter layer to enhance nitrate removal, the dynamics of which is seldom analyzed in stabilization of stormwater biofilters. Therefore, in this study of stormwater biofiltration in addition to suspended solids (turbidity), organic matter (TOC, DOC, TN, and TKN) was also monitored as a parameter for stabilization of the stormwater biofilter. One Perspex bioretention column (94 mm internal diameter) was fabricated with filter layer that contained 8 % organic material and fed with tapwater with different antecedent dry days (0-40 day) at 100 mL/min. Samples were collected from the outflow at different time intervals between 2 and 150 min and were tested for total organic carbon, dissolved organic carbon, total nitrogen, total Kjeldhal nitrogen, and turbidity. The column was observed to experience two phases of stabilization, one at the beginning of each event that lasted for 30 min, while the other phase was observed across subsequent events that are related to the age of filter.

  19. Co-optimisation of phosphorus and nitrogen removal in stormwater biofilters: the role of filter media, vegetation and saturated zone.

    Science.gov (United States)

    Glaister, Bonnie J; Fletcher, Tim D; Cook, Perran L M; Hatt, Belinda E

    2014-01-01

    Biofilters have been shown to effectively treat stormwater and achieve nutrient load reduction targets. However, effluent concentrations of nitrogen and phosphorus typically exceed environmental targets for receiving water protection. This study investigates the role of filter media, vegetation and a saturated zone (SZ) in achieving co-optimised nitrogen and phosphorus removal in biofilters. Twenty biofilter columns were monitored over a 12-month period of dosing with semi-synthetic stormwater. The frequency of dosing was altered seasonally to examine the impact of hydrologic variability. Very good nutrient removal (90% total phosphorus, 89% total nitrogen) could be achieved by incorporating vegetation, an SZ and Skye sand, a naturally occurring iron-rich filter medium. This design maintained nutrient removal at or below water quality guideline concentrations throughout the experiment, demonstrating resilience to wetting-drying fluctuations. The results also highlighted the benefit of including an SZ to maintain treatment performance over extended dry periods. These findings represent progress towards designing biofilters which co-optimise nitrogen and phosphorus removal and comply with water quality guidelines.

  20. Enhancing simultaneous nitritation and anammox in recirculating biofilters: effects of unsaturated zone depth and alkalinity dissolution of packing materials.

    Science.gov (United States)

    Wen, Jianfeng; Tao, Wendong; Wang, Ziyuan; Pei, Yuansheng

    2013-01-15

    This study investigated effects of unsaturated zone depth on nitrogen removal via simultaneous nitritation and anammox in three vertical flow recirculating biofilters. The biofilters had different depths (25, 40, and 60 cm) of an unsaturated zone and the same depth (35 cm) of a saturated zone. Unsaturated zone depth could be regulated to maintain suitable dissolved oxygen concentrations and enhance entrapment of carbon dioxide for co-occurrence of aerobic ammonia oxidation and anammox in the saturated zones. The biofilters with the larger unsaturated zones had higher ammonium and total inorganic nitrogen removal rates (16.2-33.5 g N/m(3)/d and 4.6-16.7 g N/m(3)/d, respectively) than the biofilter with the smallest unsaturated zone (11.9-18.1 g N/m(3)/d and 4.4-7.9 g N/m(3)/d, respectively). Electric arc furnace slag and marble chips were packed in the unsaturated and saturated zones, respectively, as low-cost materials to supplement alkalinity and buffer pH. Laboratory experiments showed that the maximum alkalinity dissolution efficiency was 513 mg CaCO(3)/kg marble chips and 761 mg CaCO(3)/kg electric arc furnace slag. Marble chips and electric arc furnace slag could increase dairy wastewater pH up to 7 and 9, respectively. The laboratory results are also useful for utilization of furnace slag and marble chips in constructed wetlands.

  1. A Method for Estimating Mass-Transfer Coefficients in a Biofilter from Membrane Inlet Mass Spectrometer Data

    DEFF Research Database (Denmark)

    Nielsen, Anders Michael; Nielsen, Lars Peter; Feilberg, Anders;

    2009-01-01

    A membrane inlet mass spectrometer (MIMS) was used in combination with a developed computer model to study and improve management of a biofilter (BF) treating malodorous ventilation air from a meat rendering facility. The MIMS was used to determine percentage removal efficiencies (REs) of selected...

  2. Effectiveness of Floating Micro-Bead Bio-Filter for Ornamental Fish in a Re-Circulating Aquaculture System

    Directory of Open Access Journals (Sweden)

    R Fadhil

    2011-01-01

    Full Text Available Bio-filtration has been widely used in re-circulating aquaculture system to remove waste and to convert toxic ammonia andnitrite into safe end products ornamental fish and other aquatic organisms. However, the study of micro-bead usage as the filter medium has not yet been broadened and thoroughly developed. Therefore, the aim of this study is to construct a biological filter made from polyethylene micro-bead as the filter medium and to analyze its effectiveness in removingwaste as well as in converting the toxic organic matter into stable substances. The bio-filter was constructed under a rotational molding process. The tubes, hoses, and piping were made from polyvinyl chloride (PVC while the fasteners were made from stainless steel and other non-corrosive materials. The effectiveness of this bio-filter was measured by using biochemical oxygen demand (BOD and total suspended solids (TSS analysis. Results indicated that this bio-filter is efficient enough to remove suspended solids and BOD. Therefore, this floating micro-bead bio-filter can be used in aquaculture systems.

  3. Editorial: Informationstechnische Bildung und Medienerziehung

    Directory of Open Access Journals (Sweden)

    Annemarie Hauf-Tulodziecki

    2001-10-01

    Full Text Available Die schulische Medienerziehung bzw. die Medienbildung hat ihre derzeit hohe öffentliche Aufmerksamkeit nicht zuletzt der Tatsache zu verdanken, dass gerade die so genannten «Neuen Medien» - heute oft mit den Schlagworten «Multimedia» oder «Internet» abgekürzt - wichtige Erziehungs- und Bildungsmassnahmen erforderlich machen. In der öffentlichen Diskussion gehören inhaltliche Kurzschlüsse zur Tagesordnung: Wenn von «Medienkompetenz» die Rede ist, verbirgt sich dahinter häufig nur ein «Internetführerschein». Diese Beobachtung ärgert nicht nur Medienpädagogen, sondern auch Vertreter einer Informationstechnischen Bildung (1, da berechtigte pädagogische Ansprüche beider Gruppen wenig Beachtung finden. Mittlerweile gibt es eine Reihe von Empfehlungen von BLK und KMK zu diesem Thema, in denen zudem deutlich auf die wechselseitigen Bezüge hingewiesen werden. Die wachsende Bedeutung des Mediums Computer und die weiter zunehmende Digitalisierung traditioneller Medien erfordert sowohl für die Medienerziehung als auch für die Informatische Bildung eine Weiterentwicklung ihrer Ziele und Inhalte. Die Gesellschaft für Informatik e.V. hat 1999 in ihrer Empfehlung «Informatische Bildung und Medienerziehung» aus ihrer Perspektive dargestellt, welche Aufgaben auf die Medienerziehung zukommen, wenn auch die Informations- und Kommunikationstechnologien bzw. die computerbasierten Medien in einer angemessenen Form thematisiert werden sollen. Erste praktische Ansätze, Inhalte aus beiden Bereichen bewusst zusammenzuführen, auch unter einer gemeinsamen Fach- oder Kursbezeichnung, sind häufig additiv und orientieren sich – trotz vorhandener Überschneidungen – an den etablierten medienpädagogischen oder an den informatischen Unterrichtsprinzipien. In dem vorliegenden Themenheft wird aus einer übergeordneten, medienpädagogischen Perspektive die Frage gestellt, wie eine konsistente Weiterentwicklung der Medienerziehung unter angemessener

  4. The influence of design parameters on clogging of stormwater biofilters: a large-scale column study.

    Science.gov (United States)

    Le Coustumer, Sébastien; Fletcher, Tim D; Deletic, Ana; Barraud, Sylvie; Poelsma, Peter

    2012-12-15

    A large-scale laboratory study was conducted to test the influence of design and operating conditions on the lifespan of stormwater biofilters. The evolution of hydraulic conductivity over time was studied in relation to a number of key design parameters (media type, filter depth, vegetation type, system sizing, etc). The biofilters were observed to clog over time, with average hydraulic conductivity decreasing by a factor of 3.6 over the 72 weeks of testing. The choice of plant species appears to have a significant effect on the rate of decrease in permeability, with plants with thick roots (e.g. Melaleuca) demonstrating an ability to maintain permeability over time. Other species studied, with finer roots, had no such beneficial effects. As expected, small systems relative to their catchment (and thus which are subjected to high loading rates) are more prone to clogging, as increases in hydraulic and sediment loading can lead to extremely low hydraulic conductivities. Sizing and the appropriate choice of vegetation are thus key elements in design because they can limit clogging, and therefore, indirectly increase annual load treated by limiting the volume of water bypassing the system.

  5. Hydraulic performance of biofilter systems for stormwater management: Influences of design and operation

    Science.gov (United States)

    Le Coustumer, Sébastien; Fletcher, Tim D.; Deletic, Ana; Barraud, Sylvie; Lewis, Justin F.

    2009-09-01

    SummaryIn order to evaluate the long-term performance of stormwater biofilters, a study was undertaken to assess their hydraulic conductivity. Despite variability in conductivity (40% being below the recommended range of 50-200 mm/h, 43% within it, and 17% above), treatment performance is unlikely to be affected, as most systems are over-sized such that their detention storage volume compensates for reduced media conductivity. The study broadly reveals two types of systems: some with a high initial conductivity (>200 mm/h) and some with a low initial value (biofilters in the former group, although most are shown to maintain an acceptably high conductivity. Those with initially low conductivity do not change greatly over time. Site characteristics such as filter area (relative to catchment area), age and inflow volume were not useful predictors of conductivity, with initial conductivity of the original media being the most powerful explanatory variable. It is clear therefore, that strict attention must be paid to the specification of original filter media, to ensure that it satisfies design requirements.

  6. Full-scale post denitrifying biofilters: sinks of dissolved N2O?

    Science.gov (United States)

    Bollon, Julien; Filali, Ahlem; Fayolle, Yannick; Guerin, Sabrina; Rocher, Vincent; Gillot, Sylvie

    2016-09-01

    In this study, nitrous oxide (N2O) emissions from a full-scale denitrifying biofilter plant were continuously monitored over two periods (summer campaign in September 2014 and winter campaign in February 2015). Results of the summer campaign showed that the major part (>99%) of N2O flux was found in the liquid phase and was discharged with the effluent. N2O emissions were highly variable and represented in average 1.28±1.99% and 0.22±0.31% of the nitrate uptake rate during summer and winter campaigns, respectively. Denitrification was able to consume a large amount of dissolved N2O coming from the upstream nitrification stage. In the absence of methanol injection failure and with an influent BOD/NO3-N ratio higher than 3, average reduction of N2O was estimated to be of 93%. The control of exogenous carbon dosage is essential to minimize N2O production from denitrifying biofilters, in correlation to NO2-N concentrations in the filter.

  7. Efficiency promotion and its mechanisms of simultaneous nitrogen and phosphorus removal in stormwater biofilters.

    Science.gov (United States)

    Zhou, Zijun; Xu, Peng; Cao, Xiuyun; Zhou, Yiyong; Song, Chunlei

    2016-10-01

    Stromwater biofilter technology was greatly improved through adding iron-rich soil, plant detritus and eutrophic lake sediment. Significant ammonium and phosphate removal efficiencies (over 95%) in treatments with iron-rich soil were attributed to strong adsorption capability resulting in high available phosphorus (P) in media, supporting the abundance and activity of nitrifiers and denitrifiers as well as shaping compositions, which facilitated nitrogen (N) removal. Aquatic and terrestrial plant detritus was more beneficial to nitrification and denitrification by stimulating the abundance and activity of nitrifiers and denitrifiers respectively, which increased total nitrogen (TN) removal efficiencies by 17.6% and 22.5%. In addition, bioaugmentation of nitrifiers and denitrifiers from eutrophic sediment was helpful to nutrient removal. Above all, combined application of these materials could reach simultaneously maximum effects (removal efficiencies of P, ammonium and TN were 97-99%, 95-97% and 60-63% respectively), suggesting reasonable selection of materials has important contribution and application prospect in stormwater biofilters.

  8. Biological elimination of volatile, organic compounds from waste gases in a biofilter

    Energy Technology Data Exchange (ETDEWEB)

    Wu, G.; Chabot, J.C.; Caron, J.J.; Heitz, M. [Universite de Sherbrooke, Sherbrooke, PQ (Canada). Dept. de Genie Chimique

    1998-01-01

    A great deal of research has been directed towards the problem of reduction and control of volatile organic compounds (VOCs). The aim of this research is to find a process that is both efficient and inexpensive in comparison with traditional air treatment technologies. The biofilter used, a one stage system, 2 m in height, is an aerobic system for waste gases containing VOC`s using the degradation properties of microbial flora (assorted cultures of Bacillus, Micrococcus, Acinetobacter and yeast). In this process, polluted gas diffuses across a filter bed into which a microbial culture has previously been introduced. Peat is the medium of choice for inoculation with microorganisms because of its adsorption and absorption properties, ability to retain moisture, and buffering capacity. Furthermore, the peat utilized is spherical in shape; thus, it is possible to avoid problems related to compacting. The objective of this study was to eliminate VOCs emitted from a rotogravure process. The team was able to achieve promising results from biofiltration of two types of VOCs (a mixed solvent containing isopropyl acetate and 1-nitropropane, and the solvent: 1-nitropropane). The results obtained indicate that the elimination of nitropropane and the mixed solvent in the biofilter are considered to follow zero-order kinetics with reaction rate limitation and diffusion rate limitation, respectively. 8 refs., 5 figs.

  9. Ressourceneinsatzplanung In der Energie- und Verfahrenstechnik

    Science.gov (United States)

    Engell, Sebastian; Handschin, Edmund; Rehtanz, Christian; Schultz, Rüdiger

    Der ökologisch nachhaltige, wirtschaftlich effiziente und politisch faire Umgang mit den Ressourcen der Erde ist eine der größten Herausforderungen an die Menschheit im 21. Jahrhundert und impliziert Paradigmenwechsel in allen Bereichen des gesellschaftlichen Lebens. Energie- und Verfahrenstechnik sind traditionell Bereiche, in denen der optimale Umgang mit kostbaren und beschränkt verfügbaren Ressourcen von erstrangiger Bedeutung ist. Zur Lösung der damit verbundenen komplexen Entscheidungsprobleme sind mathematische Methoden schon seit längerem im Einsatz. Hierbei können aber noch längst nicht alle bislang aufgetretenen Probleme fundiert angegangen werden. Der wachsende wirtschaftliche und ökologische Druck auf die Effizienz der Produktions-und Versorgungssysteme sowie stärkere Schwankungen von Angebot und Nachfrage führen zu neuen Herausforderungen, für die neue mathematische Methoden und Algorithmen entwickelt werden müssen.

  10. Ethnographische Filme und die Darstellung von Frauen

    Directory of Open Access Journals (Sweden)

    Judith Keilbach

    2002-03-01

    Full Text Available In dieser Filmographie werden ethnographische und koloniale Filme aus dem Bestand des Nederlands Filmmuseum kommentiert, die für die Frage nach der Darstellung von Frauen und Geschlechterverhältnissen von Interesse sind.

  11. Digitale Medien, freie Bildung und vernetztes Wissen

    OpenAIRE

    Sven Stollfuß

    2015-01-01

    Rezension zu: Petra Missomelius, Wolfgang Sützl, Theo Hug, Petra Grell und Rudolf Kammerl, Hrsg. Medien – Wissen – Bildung: Freie Bildungsmedien und Digitale Archive. Innsbruck: innsbruck university press, 2014

  12. Digitale Medien, freie Bildung und vernetztes Wissen

    Directory of Open Access Journals (Sweden)

    Sven Stollfuß

    2015-05-01

    Full Text Available Rezension zu: Petra Missomelius, Wolfgang Sützl, Theo Hug, Petra Grell und Rudolf Kammerl, Hrsg. Medien – Wissen – Bildung: Freie Bildungsmedien und Digitale Archive. Innsbruck: innsbruck university press, 2014

  13. Technik und Ergebnisse der operativen Therapie des Total- und Subtotalprolaps

    Directory of Open Access Journals (Sweden)

    Klaritsch P

    2006-01-01

    Full Text Available In einer retrospektiven Studie wurde das Outcome der operativen Therapie des Genitalprolaps an der Klinischen Abteilung für Gynäkologie zwischen 1999 und 2004 untersucht und die Ergebnisse mit der Literatur verglichen. Im beobachteten Zeitraum wurden 104 Frauen wegen eines Total- oder Subtotalprolaps des Uterus bzw. des Scheidenblindsackes an unserer Abteilung operiert. 65 Fälle mit Subtotalprolaps erfüllten die Kriterien des Stadiums III des "pelvic organ prolapse quantification system", 39 Fälle mit Totalprolaps des Uterus und Prolaps des Scheidenblindsackes wurden als Stadium IV klassifiziert. Das durchschnittliche Alter zum Zeitpunkt der Operation betrug 69,5 (46–92 Jahre. In 101 Fällen wurde ein vaginaler Zugang gewählt, während in 3 Fällen Zusatzindikationen ein abdominales Vorgehen erforderten. Intraoperative Komplikationen traten in Form von zwei Blasen- und einer Rektumläsion auf. Postoperativ kam es zu einer Nachblutung und einem Harnwegsinfekt. Im Follow-up konnten wir 69 Frauen (66 % über einen mittleren Zeitraum von 13 (1–55 Monaten nachbeobachten. In diesem Zeitraum fanden wir 13 Fälle eines Rezidivprolaps, wobei 12 der Rezidive nach vaginalem Verfahren vorkamen (11,5 %. Aus dem Vergleich der Daten mit publizierten Arbeiten läßt sich in bezug auf Rezidivraten kein Vorteil eines primär abdominalen Vorgehens ableiten. Die höhere Morbidität der abdominalen Technik, die sich mit längeren Spitalsaufenthalten und höheren Kosten zu Buche schlägt, ist zusätzlich ein wichtiger gesundheitspolitischer und ökonomischer Aspekt.

  14. Zwischen Evolutionskritik und Atheismus

    Directory of Open Access Journals (Sweden)

    Engelbert Recktenwald

    2014-04-01

    Full Text Available Thomas Nagel kritisiert den Reduktionismus und Darwinismus, bekennt sich aber gleichzeitig zum Atheismus. Sein zentrales Argument gegen den Gottesgedanken ist seine Auffassung von der Intelligibilität der Welt, das auch in seiner Kritik am Darwinismus eine große Rolle spielt. Er sieht die göttliche Freiheit als eine Bedrohung dieser Intelligibilität. Was ist davon zu halten?Between a criticism of evolution and atheism Thomas Nagel criticizes reductionism and Darwinism, but at the same time he admits that he supports atheism. His crucial argument against the notion of a divine being is his idea of intelligibility concerning the world, an argument which also plays an important part in his criticism of Darwinism. He regards divine freedom as a threat to this intelligibility. What do you think of these ideas?

  15. Wissenschaft und Praxis im Austausch – Zum aktuellen Stand qualitativer Markt-, Medien- und Meinungsforschung

    OpenAIRE

    2004-01-01

    Die steigende Bedeutung qualitativer Methoden auch für die angewandten Bereiche der Markt-, Medien- und Meinungsforschung bildet den Ausgangspunkt für diese Schwerpunktausgabe von FQS. Die Vielzahl und Verschiedenheit der veröffentlichten Beiträge macht das kreative Potenzial qualitativer Forschung nicht nur im akademischen Umfeld, sondern und auch gerade im Anwendungsbezug deutlich und zeigt, wie Wissenschaft und Praxis in einen für beide Seiten fruchtbaren Austausch miteinander treten könne...

  16. Netzwerkmitgliedschaft und Innovationsverhalten von neugegründeten und etablierten Unternehmen

    OpenAIRE

    Becker, Wolfgang; Dietz, Jürgen

    2001-01-01

    Im Mittelpunkt des Beitrages steht die Analyse der Wirkungszusammenhänge zwischen Unternehmensgründungen, etablierten Unternehmen und Innovationsnetzwerken. Ausgehend von konzeptionellen und theoretischen Überlegungen über die Beziehungen zwischen betrieblichen Innovationsaktivitäten und technologischen Möglichkeiten wird der Einfluß der Netzwerkmitgliedschaft (und weiterer Faktoren) auf das Innovationsverhalten von neugegründeten und etablierten Unternehmen untersucht. Die empirischen Analys...

  17. A contribution to the modelling of steam reformers for natural gas fuelled fuel cell heating systems; Ein Beitrag zur Modellierung von Dampfreformern fuer erdgasbetriebene Brennstoffzellenheizgeraete

    Energy Technology Data Exchange (ETDEWEB)

    Nietzsche, Joerg

    2010-10-29

    The author attempted to verify the assumptions and simplifications of common mathematical models of small-scale steam reformers. The emphasis was on the derivation of important model parameters on the basis of easily identifiable catalyst, fluid and reactor characteristics. An easily validated 2D model of a reformer tube is then used for a wide sensitivity analysis and a comparative investigation of various reactor types. [German] Die Motivation dieser Arbeit liegt in der Ueberpruefung der bislang in mathematischen Modellen von kleintechnischen Dampfreformern getroffenen Annahmen und Vereinfachungen, mit speziellem Augenmerk auf die Aufklaerung der Herkunft wichtiger Modellparameter anhand von leicht bestimmbaren Katalysator-, Fluid- und Reaktoreigenschaften. Ein leicht zu validierendes, zweidimensionales Modell eines Reformerrohres soll im Anschluss fuer eine breit angelegte Sensitivitaetsanalyse und eine vergleichende Untersuchung verschiedener Reaktortypen dienen.

  18. Zinsmodelle für Versicherungen - Diskussion der Anforderungen und Vergleich der Modelle von Hull-White und Cairns

    OpenAIRE

    Pfeiffer, Robin; Bierbaum, Jürgen; Kunze, Mathias; Quapp, Norbert; Bäuerle, Nicole

    2013-01-01

    Anwendungen von Zinsmodellen im Versicherungsbereich zeichnen sich durch die Verwendung von Zinsen verschiedener Laufzeiten, lange Vertragslaufzeiten der zu bewertenden Produkte sowie häufig einer Mindestverzinsung aus. Die Forderung einer realistischen Modellierung dieser Aspekte über lange Zeiträume hinweg ist die wesentliche Anforderung an Zinsmodelle im Versicherungsbereich. Das Fehlen beobachtbarer Preise von Versicherungsprodukten erschwert die Modellanalyse, die daher auf theoretische ...

  19. Was bringt Kompetenzanerkennung - und wem? Ein Standpunkt

    OpenAIRE

    Prokopp, Monika

    2010-01-01

    Ist Kompetenzanerkennung ein Werkzeug der „Arbeitslosenindustrie“, die Arbeitslosen, TrainerInnen, ForscherInnen und AMS-Angestellten ein mehr oder weniger gutes Auskommen bereitet und die Menschen in Kursen und auf ihren Arbeitsplätzen „kanalisiert“, damit sie nicht auf die Barrikaden steigen? Oder kann Kompetenzanerkennung nicht nur zur Qualifizierung von Menschen beitragen, sondern auch zu Empowerment, Kritik und Innovationsfähigkeit? Im ersten Teil des vorliegenden Beitrages werden Erwart...

  20. Investigation of the characteristics of biofilms grown in gas-phase biofilters with and without ozone injection by CLSM technique.

    Science.gov (United States)

    Saingam, Prakit; Xi, Jinying; Xu, Yang; Hu, Hong-Ying

    2016-02-01

    Recently, ozone injection technique was developed as a novel biomass control method to reduce bed clogging in biofilters treating volatile organic compounds (VOCs). However, the effects of ozone on the characteristics of biofilms are still unknown. In this study, two identical lab-scale biofilters treating gaseous toluene were operated in parallel except that one was continuously injected with 200 mg/m(3) ozone. Four glass slides were placed inside each biofilter on day 57 and then were taken out sequentially after 1, 2, 4, and 6 weeks of cultivation. The biofilms grown on the glass slides were stained by the ViaGram™ Red + Bacterial Gram Stain and Viability Kit and observed through the confocal laser scanning microscopy (CLSM). According to the CLSM images of 1, 2, and 4 weeks, the ozonated biofilm was significantly thinner than the control biofilm, which demonstrated that ozone could effectively control the biomass in the biofilter. For the biofilter without ozone injection, the ratios of viable cells (0.51~0.89) and the ratios of Gram-positive bacteria (0.22~0.57) both decreased within 4 weeks of cultivation. The CLSM image analysis results also demonstrated that a continuous injection of 200 mg/m(3) ozone was able to significantly enhance the ratio of viable cells to 0.77~0.97 and allow the dominance of Gram-positive bacteria in the biofilms with the ratio 0.46~0.88 instead of Gram-negative bacteria. For the 6-week samples, the biofilm thickness of the control system was reduced significantly which indicated the detachment of accumulated biofilms might occur in the samples without ozone.

  1. Economical assessment of the design, construction and operation of open-bed biofilters for waste gas treatment.

    Science.gov (United States)

    Prado, O J; Gabriel, D; Lafuente, J

    2009-06-01

    A protocol was developed with the purpose of assessing the main costs implied in the set-up, operation and maintenance of a waste gas-treating conventional biofilter. The main operating parameters considered in the protocol were the empty bed residence time and the gas flow rate. A wide variety of investment and operating costs were considered. In order to check its reliability, the protocol was applied to a number of scenarios, with biofilter volumes ranging from 8.3 to 4000 m(3). Results show that total annualized costs were between 20,000 and 220,000 euro/year and directly dependent, among other factors, on the size of the system. Total investment and operating costs for average-size compost biofilters were around 60,000 euro and 20,000 euro/year, respectively, which are concordant with actual costs. Also, a sensitivity analysis was performed in order to assess the relative influence of a series of selected costs. Results prove that operating costs are those that influence the total annual costs to a higher extent. Also, packing material replacement costs contribute significantly to the total yearly costs in biofilters with a volume higher than 800 m(3). Among operating costs, the electricity consumption is the main influencing factor in biofilters with a gas flow rate above 50,000 m(3)/h, while labor costs are critical at lower gas flow rates. In addition, the use of a variety of packing materials commonly employed in biofiltration was assessed. According to the results obtained, special attention should be paid to the packing material selected, as it is the main parameter influencing the medium replacement costs, and one of the main factors affecting investment costs.

  2. Ammonia biofiltration and nitrous oxide generation during the start-up of gas-phase compost biofilters

    Science.gov (United States)

    Maia, Guilherme D. N.; Day V, George B.; Gates, Richard S.; Taraba, Joseph L.

    2012-01-01

    Gas-Phase Biofiltration technology is widely utilized for treating ammonia gas (NH 3) with one of its potential detrimental by-products being nitrous oxide (N 2O), a potent greenhouse gas (100-y radiative forcing 298 times greater than carbon dioxide). The present work was conducted to investigate the relation between NH 3 removal during biofiltration and N 2O generation as a product of incomplete denitrification during the start-up of gas-phase compost biofilters. Four laboratory scale tubular biofilters in up flow mode (20 s residence-time) were studied for 21 days: 3 replicates were subjected to 16 ppm v (0.78 g m -2 h -1) of NH 3 and a statistical control not subjected to NH 3. Ammonia concentration differences between biofilter inlet (Bottom = 16 ppm v) and outlet (Top) and N 2O concentration differences between biofilter outlet (Top) and biofilter inlet (background concentrations at the bottom) were used to determine the extent of the correlation between NH 3 removal and N 2O generation. Correlations with CH 4 and CO 2 were also reported. The high Spearman correlation coefficients for the three replicates ( ρ = -0.845, -0.820, and -0.841, with P ≤ 0.0001 for replications A, B and C, respectively) suggested that availability of nitrate/nitrite owing to NH 3 nitrification favored conditions for N 2O generation as a sub-product of denitrification. The statistical control received no NH 3 inputs and did not generate N 2O. Therefore, the results indicated that the process of NH 3 removal was a trigger for N 2O production. Carbon dioxide and N 2O were moderately correlated. Methane and N 2O were weakly correlated and only for replicate C. No significant correlation was found for the Statistical Control between N 2O and CH 4.

  3. MoTiV - Mobility and transport in intermodal traffic. Mobility in urban areas. 'SIM-simulation models'. Final report; Mobilitaet und Transport im intermodalen Verkehr (MoTiV). Mobilitaet im Ballungsraum. 'SIM-Simulationsmodell'. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Konhaeuser, P.

    2000-11-23

    Today, modelling and simulation of traffic flow is used for the design and investigation of new systems, in particular for driver assistance and especially for on-line applications for the reconstruction of traffic state. In the project existing software tools were improved, refined and adapted for special applications in the joined project MoTiV. An emphasis was the development, provision and application of robust techniques for the traffic state estimation at existing line control equipment, where measured traffic data have been used as input. A further emphasis was the development of a model for the traffic in urban areas and the application of this model for the design and optimisation of co-ordinated control of light signal units. In this application modern control techniques and also agent-based techniques were used. Significant results are the design of controllers for ACC systems, the sensor simulations for the project ASA (turning and lane changing assistance) and the methods of the model coupling for applications of the incident detection. A highlight was the on-line application of different methods and techniques for the reconstruction of speed and density profiles and the tools for the incident detection in the context of the COMPANION system which was installed at the German highway A92. For the final demonstration in Goettingen, single vehicle data were collected with help of induction loops at the test site A92. These data were transmitted to the demonstration site, where the processing and visualisation was conducted. To get a good visual impression about the traffic states and to compare the results, a transmission of video images was transmitted parallel to the traffic data. (orig.) [German] Die Modellierung und Simulation von Verkehrsablaeufen wird heute zur Auslegung und Untersuchung von neuen Systemen, insbesondere auch Fahrerassistenzsystemen und speziell fuer On-Line-Anwendungen zur Rekonstruktion von Verkehrszustaenden (Verkehrslagen

  4. Kernspaltung und Westintegration Beispiel österreich

    Science.gov (United States)

    Forstner, Christian

    Während des Kalten Krieges erreichte in Europa sowohl die Verflechtung physikalischer Forschung mit Staat, Politik und Industrie als auch deren öffentliche Verhandlung und Bewertung eine qualitativ neuartige Dimension. Dieser Aspekt tritt am schärfsten in der Geschichte der Kernphysik und Kerntechnik hervor.

  5. Normative Praxis: konstitutions- und konstruktionsanalytische Grundlagen

    NARCIS (Netherlands)

    Stegmaier, Peter; Raab, Jürgen; et al, .

    2008-01-01

    Talcott Parsons gründet seine funktionale Handlungstheorie in Anschluss an Émile Durkheim auf die Annahme, dass kulturelle Werte und Normen ein internalisiertes System von Symbolen bilden, das von allen Gesellschaftsmitgliedern geteilt wird und ebenso den Verlauf wie den Sinn und die Legitimation vo

  6. Zeitschriftenübersicht und Buchbesprechungen

    OpenAIRE

    1991-01-01

    Zeitschriftenübersicht und Buchbesprechungen: Pohler, G./Pohler-Wagner, L. (1990): Atemzentrierte Verhaltenstherapie. Dortmund. White, M. /Epston, D. (1990) Die Zähmung der Monster. Literarische Mittel zu therapeutischen Zwecken. Heidelberg. Elbert, T. /Rockstroh, B. (1990). Psychopharmakologie. Anwendung und Wirkungsweise von Psychopharmaka und Drogen. Berlin.

  7. Mensch und Maschine in Übersetzungsprozessen

    DEFF Research Database (Denmark)

    Hansen, Gyde

    2014-01-01

    Wie kann der optimale, kombinierte Übersetzungsprozess von Mensch und Maschine aussehen, bei dem professionelle Übersetzerinnen sich auf Maschinenübersetzungen stützen können. Ihr Arbeitseinsatz und die Qualität des Übersetzungsprodukts müssen übereinstimmen und die Zieltexte sollen gebrauchstaug...

  8. Lernfeld und Prozessorientierung in der beruflichen Erstausbildung

    OpenAIRE

    Wolf, Stefan

    2007-01-01

    Die Fallstudie „Lernfeld und Prozessorientierung in der beruflichen Erstausbildung“ der Mechatroniker/in-Ausbildung untersucht moderne berufliche Bildung unter subjektwissenschaftlichen Gesichtspunkten. Im Mittelpunkt steht das lernende und handelnde Subjekt und die von ihm verlangten erweiterten beruflichen Handlungskompetenzen. Anforderungen, die bisher an die Managementausbildung gestellt wurden, werden beim Lernfeldkonzept, besonders aber bei der Prozessorientierung in der beruflichen Bil...

  9. Measurement of the heat transfer and the film cooling effectiveness at a film-cooled leading edge of a turbine blade and derivation of a local model. Pt. C: derivation of a local model. Final report; Messung von Waermeuebergang und Filmkuehleffektivitaet im Bereich der filmgekuehlten Vorderkante eines Turbinenschaufelprofils und Ableitung lokaler Modelle. T. C: Ableitung lokaler Modelle. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Schiffer, H.P.; Biba, S.

    1998-03-31

    Today, the heat transfer on a film-cooled leading edge of a high pressure turbine blade is calculated either by simple but inaccurate correlations or highly complex 3-D-simulations of the entire blade flow. The aim of the project was to derive an improved local model of the heat transfer at the leading edge in order to develop new, more precise correlations. This was done in order to minimize the cooling mass flow requirements and therefore to improve the efficiency of gas turbines. A new simple model of the near wall flow at the film cooled leading edge was derived. The model is based on the modification of the well-known turbulent boundary layer flow at a flat plate. This leads to semi-empirical correlations for the prediction of the adiabatic film cooling effectiveness and the heat transfer coefficient. The parameters of these correlations are matched to measurements at a film cooled leading edge model. By applying the correlations, the heat transfer at the leading edge can be predicted sufficiently accurate in dependence on the downstream distance, the blowing ratio and the Reynolds-number. The correlations can be implemented in existing 2-D-methods for the design of a blade cooling configuration. (orig.) [Deutsch] Der Waermeeintrag an einer filmgekuehlten Vorderkante einer Hochdruckturbinenschaufel wird derzeit mittels einfacher, nicht hinreichend genauer Korrelationen oder durch komplexe 3-D-Simulationen der Stroemung berechnet. Ziel des Vorhabens ist es, zur Minimierung des Kuehlungsmassenstroms und damit zur Wirkungsgradverbesserung der Gasturbine ein verbessertes lokales Modell des Waermeuebergangs und genauere Korrelationen herzuleiten. Im Vorhaben wurde ein Modell fuer die wandnahe Stroemung an einer filmgekuehlten Vorderkante entwickelt. Das Modell beruht auf der Modifikation der bekannten turbulenten Grenzschicht an einer ebenen Platte. Die Modellierung fuehrt zu halb-empirischen Korrelationen fuer die adiabate Filmkuehleffektivitaet und dem

  10. Contributions to the 14. Geoengineering congress in Munich. Geoengineering with the parameters time and quality; Beitraege zum 14. Geotechnik-Tag in Muenchen. Geotechnik mit den Parametern Zeit und Qualitaet

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, Norbert (ed.)

    2016-05-01

    Dietzel); Murphy's Gesetz am Beispiel der Protzenweiher Bruecke (Markus Herten, Andreas Beier); ''Daueranker'' - Stand der Technik und Langzeiterfahrungen zur Dauerhaftigkeit von Verpressankern (Karsten Beckhaus, Henning Lesemann); Optimiertes Qualitaetsmanagement fuer die Ausfuehrung von DSM-Arbeiten (W. Sondermann, W. Wehr); U-Bahnbau in Doha am Beispiel der Green Line (Guenther Heilmayer); Marmaray Project - Bosphorus Crossing Tunnels and Stations - Geotechnical Aspects (Nurettin Demir); Crossrail C310 Thames Tunnel, geotechnical and tunnel construction challenges in urban tunnelling with variable ground conditions (Andreas Raedle, Stephan Assenmacher, Ester Sophia Karl); Nachweiskonzept der Gruendung des unterirdischen Hauptbahnhofs Stuttgart 21 - Numerische Modellierung und Kalibrierung (Roberto Cudmani).

  11. Fungal/bacterial interactions during the biodegradation of TEX hydrocarbons (toluene, ethylbenzene and p-xylene) in gas biofilters operated under xerophilic conditions.

    Science.gov (United States)

    Prenafeta-Boldú, Francesc X; Guivernau, Miriam; Gallastegui, Gorka; Viñas, Marc; de Hoog, G Sybren; Elías, Ana

    2012-06-01

    The treatment of air contaminated with toluene, ethylbenzene, and p-xylene was assayed in three laboratory-scale biofilters, each consisting of two modules connected in series, packed with a pelletized organic fertilizer and inoculated with a toluene-degrading liquid enrichment culture. Biofilters were operated in parallel for 185 days in which the volumetric organic loading rate was progressively increased. The operation regime was subjected to drying out, so that packing humidity generally remained below 40%. Significant process failure occurred with ethylbenzene and p-xylene, but the toluene biofilter comparatively sustained a significant elimination capacity. Microbial community characterization by quantitative PCR and denaturing gradient gel electrophoresis showed substantial fungal enrichment in the toluene biofilter. Ribotypes identical to the well-known toluene-degrading black yeast Exophiala oligosperma (Chaetotyriales) were found among the dominant species. The microbial community structure was similar in the biofilters loaded with toluene and ethylbenzene but with p-xylene was quite specific and encompassed other chaetothyrialean fungi. Several species of Actinomycetales were found in the packing while the inoculum was dominated by representatives of the Burkholderiales and Xanthomonadales. One single fungal ribotype homologous to Acremonium kiliense was detected in the inoculum. The implications of xerophilic biofilter operation on process biosafety and efficiency are discussed.

  12. Moisture effects on greenhouse gases generation in nitrifying gas-phase compost biofilters.

    Science.gov (United States)

    Maia, Guilherme D N; Day, George B; Gates, Richard S; Taraba, Joseph L; Coyne, Mark S

    2012-06-01

    Gas-phase compost biofilters are extensively used in concentrated animal feeding operations to remove odors and, in some cases, ammonia from air sources. The expected biochemical pathway for these predominantly aerobic systems is nitrification. However, non-uniform media with low oxygen levels can shift biofilter microbial pathways to denitrification, a source of greenhouse gases. Several factors contribute to the formation of anoxic/anaerobic zones: media aging, media and particle structure, air velocity distribution, compaction, biofilm thickness, and moisture content (MC) distribution. The present work studies the effects of media moisture conditions on ammonia (NH(3)) removal and greenhouse gas generation (nitrous oxide, N(2)O and methane, CH(4)) for gas-phase compost biofilters subject to a 100-day controlled drying process. Continuous recordings were made for the three gases and water vapor (2.21-h sampling cycle, each cycle consisted of three gas species, and water vapor, for a total of 10,050 data points). Media moisture conditions were classified into three corresponding media drying rate (DR) stages: Constant DR (wetter media), falling DR, and stable-dry system. The first-half of the constant DR period (0-750 h; MC=65-52%, w.b.) facilitated high NH(3) removal rates, but higher N(2)O generation and no CH(4) generation. At the drier stages of the constant DR (750-950 h; MC=52-48%, w.b.) NH(3) removal remained high but N(2)O net generation decreased to near zero. In the falling DR stage (1200-1480 h; MC=44-13%) N(2)O generation decreased, CH(4) increased, and NH(3) was no longer removed. No ammonia removal or greenhouse gas generation was observed in the stable-dry system (1500-2500 h; MC=13%). These results indicate that media should remain toward the drier region of the constant DR (in close proximity to the falling DR stage; MC=50%, approx.), to maintain high levels of NH(3) removal, reduced levels of N(2)O generation, and nullify levels of CH(4

  13. Comparison of NOx Removal Efficiencies in Compost Based Biofilters Using Four Different Compost Sources

    Energy Technology Data Exchange (ETDEWEB)

    Lacey, Jeffrey Alan; Lee, Brady Douglas; Apel, William Arnold

    2001-06-01

    In 1998, 3.6 trillion kilowatt-hours of electricity were generated in the United States. Over half of this was from coal-fired power plants, resulting in more than 8.3 million tons of nitrogen oxide (NOx) compounds being released into the environment. Over 95% of the NOx compounds produced during coal combustion are in the form of nitric oxide (NO). NOx emission regulations are becoming increasingly stringent, leading to the need for new, cost effective NOx treatment technologies. Biofiltration is such a technology. NO removal efficiencies were compared in compost based biofilters using four different composts. In previous experiments, removal efficiencies were typically highest at the beginning of the experiment, and decreased as the experiments proceeded. This work tested different types of compost in an effort to find a compost that could maintain NO removal efficiencies comparable to those seen early in the previous experiments. One of the composts was wood based with manure, two were wood based with high nitrogen content sludge, and one was dairy compost. The wood based with manure and one of the wood based with sludge composts were taken directly from an active compost pile while the other two composts were received in retail packaging which had been out of active piles for an indeterminate amount of time. A high temperature (55-60°C) off-gas stream was treated in biofilters operated under denitrifying conditions. Biofilters were operated at an empty bed residence time of 13 seconds with target inlet NO concentrations of 500 ppmv. Lactate was the carbon and energy source. Compost was sampled at 10-day intervals to determine aerobic and anaerobic microbial densities. Compost was mixed at a 1:1 ratio with lava rock and calcite was added at 100g/kg of compost. In each compost tested, the highest removal efficiencies occurred within the first 10 days of the experiment. The wood based with manure peaked at day 3 (77.14%), the dairy compost at day 1 (80.74%), the

  14. [Die baltischen Lande im Zeitalter der Reformation und Konfessionalisierung : Livland, Estland, Ösel, Ingermanland, Kurland und Lettgallen : Stadt, Land und Konfession 1500-1721. Teil 4. Hrsg. von Matthias Asche, Werner Buchholtz und Anton Schindlin

    Index Scriptorium Estoniae

    Maasing, Madis, 1984-

    2013-01-01

    Arvustus: Die baltischen Lande im Zeitalter der Reformation und Konfessionalisierung : Livland, Estland, Ösel, Ingermanland, Kurland und Lettgallen : Stadt, Land und Konfession 1500-1721. Teil 4. (Katholisches Leben und Kirchenreform im Zeitalter der Glaubensspaltung, 72). Hrsg. von Matthias Asche, Werner Buchholtz und Anton Schindling. Verlag Aschendorff. Münster 2012

  15. Restaurierung von Seen und Renaturierung von Seeufern

    Science.gov (United States)

    Grüneberg, Björn; Ostendorp, Wolfgang; Leßmann, Dieter; Wauer, Gerlinde; Nixdorf, Brigitte

    Süßwasserseen haben als ökosysteme und Lebensraum für Pflanzen und Tiere eine herausragende Bedeutung für die Artenvielfalt auf der Erde und prägen als Landschaftselemente unsere natürliche Umwelt. Seen fungieren als natürliche Stoffsenken, vor allem für Kohlenstoff und Nährstoffe, aber auch als Senken für in ihren Einzugsgebieten emittierte gelöste und feste Schadstoffe. Darüber hinaus ist Wasser eine wichtige Naturressource. Süßwasserseen stellen in den meisten Regionen der Erde lebenswichtige Quellen für die Versorgung mit Trinkwasser und tierischem Eiweiß (Fischfang) dar. Sie dienen als Wasserspeicher für die landwirtschaftliche und industrielle Nutzung. Auch für Erholungsaktivitäten des Menschen kommt ihnen eine große Bedeutung zu.

  16. Boulevardisierung – Fernsehunterhaltung zwischen Quality und Trash?

    Directory of Open Access Journals (Sweden)

    Elisabeth Klaus

    2015-07-01

    Full Text Available Der Diskussionsbeitrag reflektiert anhand zweier unterschiedlicher neuerer Fernsehangebote, die als Reality TV und als „Quality TV“ bezeichnet werden, wie Qualitätsurteile von Medienkritik und Medienwissenschaft gefällt werden. Unter einer feministischen Perspektive wird beispielhaft gezeigt, dass Geschlechterstereotype und die Trivialisierung von Menschen, die nicht der weißen Mittelschicht angehören, die Serien in beiden Angebotsformen dominieren und es gleichermaßen dazu auch andere Beispiele gibt. Für eine kritische Medienforschung ist es zwingend, die verschiedenen Momente des Medienprozesses – Produktionsprozess, Medientext und Rezeption – nicht in eins zu setzen und gleichermaßen ästhetische und ideologische Aspekte in Qualitätsurteilen zu berücksichtigen.

  17. Ethik, Recht und Theologie. Reproduktionstechnologien in Polen

    Directory of Open Access Journals (Sweden)

    Susanne Lettow

    2006-03-01

    Full Text Available Die bisherigen Debatten um Stammzellforschung, Klonen und Reproduktionstechnologien wurden in Deutschland weitgehend im nationalstaatlichen Rahmen und mit Blick auf Entwicklungen im angelsächsischen Raum geführt. Dabei sind diese Forschungsrichtungen und Technologien kein genuin „westliches“ Phänomen – immerhin wurde das erste Retortenkind in Polen bereits 1987 geboren. Heidi Hofmann lässt in ihrem Band polnische Philosoph/-innen, Jurist/-innen und Politikerinnen zu Wort kommen und öffnet den Blick dafür, dass die Art und Weise, in der Reproduktionstechnologien gesellschaftlich problematisiert werden, in Polen durch ganz andere politische, kulturelle und historische Konstellationen geprägt ist als in Deutschland.

  18. Pluralismus von Recht und Ordnung

    Directory of Open Access Journals (Sweden)

    Franz von Benda- Beckmann

    2008-04-01

    Full Text Available Der Beitrag befasst sich mit der Frage, wie sich die Beziehungen zwischen Recht und Ordnung in rechtspluralistischen Kontexten darstellen. Die wechselhafte Geschichte der Minangkabau in West Sumatra, bei denen staatliches, islamisches und traditionelles Adatrecht koexistieren, zeigt, dass die unterschiedlichen Inhalte der Teilrechtsordnungen und die mit ihnen verbundenen Autoritäten zwar nicht notwendigerweise zu sozialen Konflikten führen müssen, die Ordnung jedoch riskanter machen. Das Potential für soziale Konflikte nimmt zu, wenn sich inhaltlich unterschiedliche rechtliche Entwürfe der sozialen Organisation auf unterschiedliche Legitimationsgrundlagen berufen können, welche die legitime Macht der hinter einer Ordnung stehenden Autoritäten relativieren.

  19. Thromboserisiko und kombinierte orale Kontrazeption

    Directory of Open Access Journals (Sweden)

    Martinez M

    2015-01-01

    Full Text Available Die Entwicklung der Antibabypille zur Lifestyle-Behandlung brachte zunehmendes Risiko für thromboembolische Ereignisse mit sich. Die heutigen Kombinationen von Ethinylestradiol mit Gestagenen, welche antiandrogene Eigenschaften besitzen (Drospirenon, Cyproteron, haben die Kontrazeption komfortabler gemacht, allerdings zulasten eines höheren Risikos für thromboembolische Komplikationen. Gestagene der früheren Generationen, insbesondere das Levonorgestrel, können die ungünstige Wirkung von Ethinylestradiol auf die Gerinnungsproteine teilweise kompensieren und das Thromboserisiko tiefer halten. Levonorgestrel bewirkt allerdings einen leichten androgenen Effekt und hat diesbezüglich ein schlechteres Nebenwirkungsprofil als die neueren KOKs. Die Monogestagenprodukte (Pille, Spirale gehen mit eindeutig tieferen Thromboseraten als die kombinierten Produkte einher. Im Folgenden werden Mechanismen, Erkennungsmöglichkeiten und Behandlung dieser Risiken aus hämatologischer Sicht diskutiert.

  20. CLILiG und Musikunterricht

    Directory of Open Access Journals (Sweden)

    Merle Jung

    2015-10-01

    Full Text Available Der Einsatz von Musik und Liedern im Sprachunterricht ist seit der Entwicklung der kommunikativen Methoden ein beliebtes Thema in der Fremdsprachendidaktik. Musik und Sprache haben Ähnlichkeiten bei den kognitiven Verarbeitungsprozessen und der gedächtnisstützende Einfluss der Musik und ihr Nutzen für das Sprachenlernen sind allgemein bekannt. Dieser Nutzen wird aber meistens nur aus der (fremdsprachlichen Perspektive gezogen, die musikalische Erziehung der Lernenden bleibt im Hintergrund. Dabei bietet der bilinguale Musikunterricht mit der klaren Ausrichtung auf die musikalischen Ziele eine gute Möglichkeit, diese zwei Bereiche – Musik und Sprache – gleichwertig miteinander zu verbinden. Das Ziel des vorliegenden Beitrags ist es, die Vorteile des bilingualen Musikunterrichts zu erörtern und an einem Beispielmodul zum Thema Wetter im Herbst zu verdeutlichen. The use of music and songs in language teaching has been a popular topic in foreign language didactics since the development of communicative methods. Music and language have similarities in cognitive processing and the memory supporting influence of music and its beneficial effect on language learning are generally known. However, this benefit will usually be drawn only from the (foreign language perspective, the musical education of the learners remains in the background. Yet bilingual music education with a clear focus on the musical goals provides a great opportunity to connect these two areas - music and language - equally to each other. The aim of this paper is to discuss the advantages of bilingual music education and to present an example based on the bilingual module Weather in Autumn.

  1. Osteoporose und Genetik des Knochenstoffwechsels

    Directory of Open Access Journals (Sweden)

    Obermayer-Pietsch B

    2002-01-01

    Full Text Available Osteoporose ist in hohem Maß genetisch determiniert. Neue Wege der molekularbiologischen Forschung haben sich in den letzten Jahren auf diesem Gebiet etabliert. "Gene mapping" mit polymorphen genetischen Markern auf der Suche nach Phänotyp-assoziierten Genen ist ein aufwendiges, aber vielversprechendes Verfahren und wird durch die Erkenntnisse des Human Genome Projects beschleunigt. So wurde jüngst u. a. das Low-density Lipoprotein 5-Gen als wichtig für den Knochenstoffwechsel identifiziert. Kandidaten-gene wie Hormonrezeptor-, Cytokin- oder Kollagen-Gene werden hinsichtlich ihrer Gen-Gen- und Gen-Umwelt- Interaktionen untersucht und erlauben neue funktionelle Einsichten in Erkrankungen des Knochenstoffwechsels. Mutationen der Kollagen-Gene sind bei einigen seltenen Erkrankungen, wie dem Osteoporose-Pseudogliom-Syndrom oder der Osteogenesis imperfecta gefunden worden, könnten aber auch für häufige Varianten von Bindegewebsstörungen wie der congenitalen Hüftdysplasie verantwortlich sein, die etwa 10 % der weiblichen kaukasischen Bevölkerung in unterschiedlichem Ausmaß betrifft. Osteoporose am Schenkelhals und erhöhte Gelenkslaxizität sowie andere generalisierte Veränderungen des Knochen- und Kollagenstoffwechsels können hier möglicherweise ebenfalls durch Störungen des Kollagen I alpha 1-Gens erklärt werden. In Summe können wir zahlreiche neue Einsichten in die Pathophysiologie des Skelettsystems erwarten, die uns auch neue Zugangswege für Diagnostik und Therapie unserer Patienten ermöglichen werden.

  2. Pathogenese und Genetik der Gallensteinbildung

    Directory of Open Access Journals (Sweden)

    Lamottke S

    2014-01-01

    Full Text Available Gallensteine sind außerordentlich häufig und verursachen durch Schmerzen und Komplikationen hohe Kosten für Gesundheitssysteme. Das individuelle Risiko, Gallensteine auszubilden, wird durch die Interaktionen prädisponierender Varianten lithogener (LITH - Gene und Umweltfaktoren bestimmt. Es sind die häufigeren Cholesteringallensteine von den sehr viel selteneren Bilirubingallensteinen zu unterscheiden. Beide Steintypen differieren in ihrer Pathogenese und in den zugrunde liegenden Risikofaktoren. Cholesteringallensteine entstehen, wenn die Galle mit Cholesterin übersättigt ist, wie bei starkem Gewichtsverlust, der Einnahme bestimmter Medikamente oder im letzten Trimenon einer Schwangerschaft. Zusätzlich führt eine verminderte Gallenblasenkontraktilität durch Einlagerung von Cholesterin in die Gallenblasenwand, eine fettarme Diät oder die Einnahme von Somatostatinanaloga zu einer längeren Verweildauer der Galle in der Gallenblase. Schließlich sezernieren die Cholangiozyten der Gallenblase Muzine, die ein Gel bilden, das als Nukleationsmatrix für Cholesterinkristalle erforderlich ist. Wesentliche LITH-Gene sind ABCG8 (das gemeinsam mit ABCG5 den intestinalen und hepatozellulären Cholesterintransporter kodiert sowie UGT1A1, das die UDP-Glukuronyltransferase kodiert, die das wasserunlösliche indirekte Bilirubin konjugiert. Bilirubinsteine entstehen bei einer erhöhten Bilirubinsekretion in die Galle wie bei Hämolyse, ineffektiver Erythropoese und einem induzierten enterohepatischen Kreislauf von Bilirubin durch Gallensäureverlust infolge eines Morbus Crohn oder einer Ileumresektion. Weitere Risikofaktoren sind eine verminderte Glukuronidierung des Bilirubins bei Leberzirrhose. Varianten des UGT1A1-Gens, die zu einer verminderten Bildung der UDP-Glukuronyltransferase führen, erhöhen das Risiko für Bilirubingallensteine.

  3. Assessing the Efficacy of the Aerobic Methanotrophic Biofilter in Methane Hydrate Environments

    Energy Technology Data Exchange (ETDEWEB)

    Valentine, David

    2012-09-30

    In October 2008 the University of California at Santa Barbara (UCSB) initiated investigations of water column methane oxidation in methane hydrate environments, through a project funded by the National Energy Technology Laboratory (NETL) entitled: assessing the efficacy of the aerobic methanotrophic biofilter in methane hydrate environments. This Final Report describes the scientific advances and discoveries made under this award as well as the importance of these discoveries in the broader context of the research area. Benthic microbial mats inhabit the sea floor in areas where reduced chemicals such as sulfide reach the more oxidizing water that overlies the sediment. We set out to investigate the role that methanotrophs play in such mats at locations where methane reaches the sea floor along with sulfide. Mats were sampled from several seep environments and multiple sets were grown in-situ at a hydrocarbon seep in the Santa Barbara Basin. Mats grown in-situ were returned to the laboratory and used to perform stable isotope probing experiments in which they were treated with 13C-enriched methane. The microbial community was analyzed, demonstrating that three or more microbial groups became enriched in methane?s carbon: methanotrophs that presumably utilize methane directly, methylotrophs that presumably consume methanol excreted by the methanotrophs, and sulfide oxidizers that presumably consume carbon dioxide released by the methanotrophs and methylotrophs. Methanotrophs reached high relative abundance in mats grown on methane, but other bacterial processes include sulfide oxidation appeared to dominate mats, indicating that methanotrophy is not a dominant process in sustaining these benthic mats, but rather a secondary function modulated by methane availability. Methane that escapes the sediment in the deep ocean typically dissolved into the overlying water where it is available to methanotrophic bacteria. We set out to better understand the efficacy of this

  4. The use of biofilters to improve indoor air quality: the removal of toluene, TCE, and formaldehyde.

    Science.gov (United States)

    Darlington, A; Dixon, M A; Pilger, C

    1998-01-01

    A biofilter composed of a scrubber, a hydroponic planting system, and an aquatic system with green plants as a base maintained air quality within part of a modern office building. The scrubber was composed of five parallel fiberglass modules with external faces of porous lava rock. The face, largely covered with mosses, was wetted by recirculating water. Air was drawn through the scrubber and the immediately adjacent hydroponic region by a dedicated air handling system. The system was challenged for 4 weeks with three common indoor organic pollutants and removed significant amounts of all compounds. A single pass through the scrubber removed 10% of the trichloroethylene and 50% of the toluene. A single pass lowered formaldehyde air concentrations to 13 micrograms m-3 irrespective of influent levels (ranging between 30 and 90 micrograms m-3). The aquatic system accumulated trichloroethylene but neither toluene nor formaldehyde, suggesting the rapid breakdown of these materials. The botanical components removed some pollutants.

  5. [Potential of nitrification and denitrification in water purification system with hydroponic bio-filter method].

    Science.gov (United States)

    Li, Xian-ing; Lu, Xi-wu; Song, Hai-liang; Osamu, Nishimura; Yuhei, Inamori

    2005-03-01

    The potential of nitrification and denitrification of sediment and the density of ammonium-oxidizing bacteria and nitrite-oxidizing bacteria in sediment in water quality purifying system with hydroponic bio-filter method (HBFM) were measured. The variation of nitrification and denitrification potential of the sediment along the stream way was quantitatively studied. The results show that among the sediments from front, middle and retral part of the stream way, the sediment from middle part reached a maximum nitrification potential . nitrification potential of 4.76 x 10(-6) g/(g x h), while the sediment from front part reached a maximum denitrification potential of 8 .1 x 10(-7) g/(g x h). The distribution of nitrification potential accords with the ammonium-oxidizing bacteria density. The key for improving nitrogen removal efficiency of HBFM system consists in changing nitrification & denitrification region distributing and accordingly enhances denitrification process.

  6. Klinefelter-Syndrom und Krebs

    Directory of Open Access Journals (Sweden)

    Kliesch S

    2012-01-01

    Full Text Available - Männer mit Klinefelter-Syndrom haben kein erhöhtes Gesamtrisiko für Krebserkrankungen.br - Gehäuft treten jedoch das virile Mammakarzinom und extragonadale, meist im Mediastinum lokalisierte Keimzelltumoren auf. Mammakarzinome treten eher bei älteren Männern, Keimzelltumoren meistens vor dem 30. Lebensjahr auf.br - Die Daten zu erhöhter Inzidenz bzw. Mortalität bei hämatologischen Neoplasien und bei Bronchialkarzinom sind nicht eindeutig.br - Das Risiko für ein Prostatakarzinom ist erniedrigt.br

  7. Klinefelter-Syndrom und Krebs

    Directory of Open Access Journals (Sweden)

    Kliesch S

    2014-01-01

    Full Text Available – Männer mit Klinefelter-Syndrom haben kein erhöhtes Gesamtrisiko für Krebserkrankungen. – Gehäuft treten jedoch das virile Mammakarzinom und extragonadale, meist im Mediastinum lokalisierte Keimzelltumoren auf. Mammakarzinome treten eher bei älteren Männern, Keimzelltumoren meistens vor dem 30. Lebensjahr auf. – Die Daten zu erhöhter Inzidenz bzw. Mortalität bei hämatologischen Neoplasien und bei Bronchialkarzinom sind nicht eindeutig. – Das Risiko für ein Prostatakarzinom ist erniedrigt.

  8. Methodologies for pre-validation of biofilters and wetlands for stormwater treatment.

    Directory of Open Access Journals (Sweden)

    Kefeng Zhang

    Full Text Available Water Sensitive Urban Design (WSUD systems are frequently used as part of a stormwater harvesting treatment trains (e.g. biofilters (bio-retentions and rain-gardens and wetlands. However, validation frameworks for such systems do not exist, limiting their adoption for end-uses such as drinking water. The first stage in the validation framework is pre-validation, which prepares information for further validation monitoring.A pre-validation roadmap, consisting of five steps, is suggested in this paper. Detailed methods for investigating target micropollutants in stormwater, and determining challenge conditions for biofilters and wetlands, are provided.A literature review was undertaken to identify and quantify micropollutants in stormwater. MUSIC V5.1 was utilized to simulate the behaviour of the systems based on 30-year rainfall data in three distinct climate zones; outputs were evaluated to identify the threshold of operational variables, including length of dry periods (LDPs and volume of water treated per event.The paper highlights that a number of micropollutants were found in stormwater at levels above various worldwide drinking water guidelines (eight pesticides, benzene, benzo(apyrene, pentachlorophenol, di-(2-ethylhexyl-phthalate and a total of polychlorinated biphenyls. The 95th percentile LDPs was exponentially related to system design area while the 5th percentile length of dry periods remained within short durations (i.e. 2-8 hours. 95th percentile volume of water treated per event was exponentially related to system design area as a percentage of an impervious catchment area.The out-comings of this study show that pre-validation could be completed through a roadmap consisting of a series of steps; this will help in the validation of stormwater treatment systems.

  9. Performance of rotating drum biofilter for volatile organic compound removal at high organic loading rates

    Institute of Scientific and Technical Information of China (English)

    YANG Chunping; CHEN Hong; ZENG Guangming; ZHU Xueqing; SUIDAN Makram T

    2008-01-01

    Uneven distribution of volatile organic compounds (VOCs) and biomass,and excess biomass accumulation in some biofilters hinder the application of biofiltration technology.An innovative multilayer rotating drum biofilter (RDB) was developed to correct these problems.The RDB was operated at an empty bed contact time (EBCT) of 30 s and a rotational rate of 1.0 r/rain.Diethyl ether was chosen as the model VOC.Performance of the RDB was evaluated at organic loading rates of 32.1,64.2,128,and 256 g ether/(m3·h) (16.06 g ether/(m3·h) ≈1.0 kg chemical oxygen demand (COD)/(m3·d)).The EBCT and organic loading rates were recorded on the basis of the medium volume.Results show that the ether removal efficiency decreased with an increased VOC loading rate.Ether removal efficiencies exceeding 99% were achieved without biomass control even at a high VOC loading rate of 128 g ether/(m3·h). However,when the VOC loading rate was increased to 256 g ether/(m3·h),the average removal efficiency dropped to 43%.Nutrient limitation possibly contributed to the drop in ether removal efficiency.High biomass accumulation rate was also observed in the medium at the two higher ether loading rates,and removal of the excess biomass in the media was necessary to maintain stable performance. This work showed that the RDB is effective in the removal of diethyl ether from waste gas streams even at high organic loading rates. The results might help establish criteria for designing and operating RDBs.

  10. A method for enhanced control of biomass activity and distribution in biofilters

    Energy Technology Data Exchange (ETDEWEB)

    Song, J.H.; Kinney, K.A.

    1999-07-01

    Long-term performance of vapor-phase bioreactors can be unreliable because of uneven distribution of biomass and microbial activity throughout the bioreactors. One method to improve biomass distribution and maintain high removal efficiencies for continuous long-term use is to operate the bioreactor in a directionally-switching (DS) mode, in which the contaminant inlet is periodically switched between the top and bottom of the reactor column. The objective of this study was to evaluate the effect of DS operation on biomass distribution and activity. Two identical lab-scale biofilters were operated for 96 days at an inlet toluene concentration of 200 ppmv and an EBCT of 1 minute. One bioreactor operated in a unidirectional (UD) mode where the air stream was continuously fed to the bottom of the reactor, and the other operated in a DS mode in which the direction of the air stream through the bioreactor was reversed every 3 days. After an initial acclimation period, toluene removal efficiencies of over 99.9% were achieved in both bioreactors for over 40 days of operation. However, toluene removal efficiencies in the UD biofilter declined after 70 days and the pressure drop across the reactor increased quickly, whereas the DS reactor maintained relatively stable operation throughout the same period. The biomass distribution determined by volatile solids and plate counts indicates that the biomass was well distributed in the DS reactor, while excess biomass accumulated in the inlet section of the UD bioreactor. INT (iodonitrotetrazolium chloride) formazan assays were performed to estimate the biomass activity along the length of both bioreactors. These results reveal that biomass activity was more evenly distributed and sustained in the DS bioreactor, but in the UD bioreactor most of the bioactivity was confined to the front half of the bed.

  11. Biometrie und Datenschutz; Bedrohungen und Privacy-Enhancing Technologies

    NARCIS (Netherlands)

    Borking, J.J.; Verhaar, P.J.A.

    1999-01-01

    Dies er Beitrag beschreibt Bedrohungen der Privatsphare, die durch den Einsatz und die Nutzung biometrischer Technologien entstehen können. Die Autoren skizzieren, welche (technischen) Massnahmen ergriffen werden können, um die Auswirkungen dieser Bedrohungen zu verringern oder sogar zu beseitigen

  12. [Preussen und Livland im Zeichen der Reformation] / Anti Selart

    Index Scriptorium Estoniae

    Selart, Anti, 1973-

    2015-01-01

    Arvustus: Preussen und Livland im Zeichen der Reformation. Hrsg. von Arno Mentzel-Reuters und Klaus Neitmann. (Tagungsberichte der Historischen Kommission für ost- und westpreussische Landesforschung, 28). Fibre Verlag. Osnabrück 2014

  13. Editorial: Neue Medien und individuelle Leistungsdarstellung: Möglichkeiten und Grenzen von ePortfolios und eAssessments

    Directory of Open Access Journals (Sweden)

    Claudia de Witt

    2010-03-01

    Full Text Available Der Einsatz digitaler Medien in formellen Lernzusammenhängen (Schule, Hochschule, berufliche Bildung etc. bietet neue Möglichkeiten, die Kenntnisse und Kompetenzen Lernender darzustellen bzw. abzubilden. So sollen z.B. Instrumente wie E-Portfolios eine selbstbestimmtere Leistungsdarstellung ermöglichen: Lernende sollen ihren Lernprozess dokumentieren und reflektieren, sich ihrer Verantwortung für ihn bewusst werden und ihn im Idealfall selbst steuern, Lehrende nehmen dabei eine beratende und unterstützende Rolle ein. Allerdings sind die Erwartungen und Ansprüche an E-Portfolios sehr unterschiedlich; sie reichen von standardisierten, formalisierten Qualifikationsdarstellungen für den beruflichen Wettbewerbsmarkt bis hin zu individuellen Kompetenzprofilen. Zwar sind in Lehr-Lern-Arrangements weiterhin quantitative Bewertungen von Leistungen weit verbreitet, doch finden sich zunehmend auch qualitative Anteile z.B. durch den Einsatz von E-Portfolios. Dabei werden diese in bestehende Lehr- und Lernkulturen integriert, die sie gleichzeitig verändern. Die Frage ist auch, was mit E-Portfolios erreicht werden soll: Geht es um eine stärkere Förderung der Selbstlernkompetenz und um die Fähigkeit, sich eigenverantwortlich den Forderungen nach lebensbegleitendem Lernen stellen zu können? Sollen individuelle Stärken und Schwächen transparenter werden, um die eigene Reflexion von Bildungsreife wie auch deren Einschätzung und Bewertung durch Ausbildungspersonal zu erleichtern? Oder geht es um beides? Unter dem Oberbegriff E-Assessment dagegen lassen sich computer- bzw. internetgestützte Prüfungsformen (z.B. E-Klausuren zusammenfassen, die anders als E-Portfolios eine möglicherweise objektivere und vergleichbarere Bewertungsgrundlage für die Identifizierung, Darstellung und Reflexion individueller Leistungen bieten. Zu hinterfragen ist in jedem Fall, welchen Stellenwert Selbstreflexion und Selbststeuerung in immer stärker durchorganisierten

  14. Resistance and resilience of removal efficiency and bacterial community structure of gas biofilters exposed to repeated shock loads.

    Science.gov (United States)

    Cabrol, Léa; Malhautier, Luc; Poly, Franck; Roux, Xavier Le; Lepeuple, Anne-Sophie; Fanlo, Jean-Louis

    2012-11-01

    Since full-scale biofilters are often operated under fluctuating conditions, it is critical to understand their response to transient states. Four pilot-scale biofilters treating a composting gas mixture and undergoing repeated substrate pulses of increasing intensity were studied. A systematic approach was proposed to quantify the resistance and resilience capacity of their removal efficiency, which enabled to distinguish between recalcitrant (ammonia, DMDS, ketones) and easily degradable (esters and aldehyde) compounds. The threshold of disturbing shock intensity and the influence of disturbance history depended on the contaminant considered. The spatial and temporal distribution of the bacterial community structure in response to the perturbation regime was analysed by Denaturing Gradient Gel Electrophoresis (DGGE). Even if the substrate-pulses acted as a driving force for some community characteristics (community stratification), the structure-function relationships were trickier to evidence: the distributions of resistance and composition were only partially coupled, with contradictory results depending on the contaminant considered.

  15. Effectiveness of probiotic Phaeobacter bacteria grown in biofilters against Vibrio anguillarum infections in the rearing of Turbot (Psetta maxima) larvae.

    Science.gov (United States)

    Prol-García, María J; Pintado, José

    2013-12-01

    The rearing environment of first-feeding turbot larvae, usually with high larvae densities and organic matter concentrations, may promote the growth of opportunistic pathogenic Vibrionaceae bacteria, compromising the survival of the larvae. The aim of this study was to assess the effectiveness of the biofilm-forming probiotic Phaeobacter 27-4 strain grown on a ceramic biofilter (probiofilter) in preventing Vibrio anguillarum infections in turbot larvae. In seawater with added microalgae and maintained under turbot larvae rearing conditions, the probiofilter reduced the total Vibrionaceae count and the concentration of V. anguillarum, which was undetectable after 144 h by real-time PCR. The probiofilter also improved the survival of larvae challenged with V. anguillarum, showing an accumulated mortality similar to that of uninfected larvae (35-40 %) and significantly (p biofilters can constantly inoculate probiotics into rearing tanks and are therefore potentially useful for bacterial control in both open and recirculating industrial units.

  16. Nitrogen removal in micro-polluted surface water by the combined process of bio-filter and ecological gravel bed.

    Science.gov (United States)

    Sheng-Bing, He; Jian-Wen, Gao; Xue-Chu, Chen; Ding-Li, Dai

    2013-01-01

    Nitrogen removal in micro-polluted surface water by the combined process of a bio-filter and an ecological gravel bed was studied. Sodium acetate was added into micro-polluted surface water as carbon source and the nitrogen removal under different C/N ratio, hydraulic load and temperature were investigated. The results showed that the variations in C/N ratio, hydraulic load and temperature have significant influence on nitrogen removal in bio-filter. It was found that the denitrification rate was above 90% when C/N ratio reached 10; also, the denitrification was inhibited at low water temperature (2-10 °C); at the condition of water temperature above 20 °C, C/N ratio 10, hydraulic load 8 m(3)/(m(2) h), the combined process obtained the nitrogen removal of more than 90%, and the residual organics could be removed in ecological gravel bed.

  17. Silica sol-gel encapsulated methylotrophic yeast as filling of biofilters for the removal of methanol from industrial wastewater.

    Science.gov (United States)

    Kamanina, Olga A; Lavrova, Daria G; Arlyapov, Viacheslav A; Alferov, Valeriy A; Ponamoreva, Olga N

    2016-10-01

    This research suggests the use of new hybrid biomaterials based on methylotrophic yeast cells covered by an alkyl-modified silica shell as biocatalysts. The hybrid biomaterials are produced by sol-gel chemistry from silane precursors. The shell protects microbial cells from harmful effects of acidic environment. Potential use of the hybrid biomaterials based on methylotrophic yeast Ogataea polymorpha VKM Y-2559 encapsulated into alkyl-modified silica matrix for biofilters is represented for the first time. Organo-silica shells covering yeast cells effectively protect them from exposure to harmful factors, including extreme values of pH. The biofilter based on the organic silica matrix encapsulated in the methylotrophic yeast Ogataea polymorpha BKM Y-2559 has an oxidizing power of 3 times more than the capacity of the aeration tanks used at the chemical plants during methyl alcohol production. This may lead to the development of new and effective industrial wastewater treatment technologies.

  18. Kalium und Magnesium in der Pulmologie

    Directory of Open Access Journals (Sweden)

    Veichtlbauer CD

    2003-01-01

    Full Text Available In der vorliegenden Arbeit soll anhand von zwei epidemiologischen und einer klinischen Studie der Einfluß von K und Mg auf die Funktion der Bronchien beurteilt werden. Die epidemiologischen Studien zeigen, daß die Aufnahme von K und Mg vom Alter und Geschlecht der PatientInnen abhängig ist. So zeigt die Arbeit von Gilliland, daß Knaben mehr Mg und K zuführen als gleichaltrige Mädchen, wobei sich die K-Zufuhr im Bereich der empfohlenen Tagesdosis bewegt. Britton wiederum beschreibt eine verminderte Mg-Zufuhr mit zunehmendem Alter. Die klinische und die epidemiologischen Arbeiten zeigen auch, daß ein niedriger Mg-Intake zu einer weiteren Reduktion der Funktionsparameter der bronchialen Obstruktion führen können und möglicherweise eine therapeutische Intervention mit Mg bei mit Theophyllin behandelten obstruktiven PatientInnen zu einer Verbesserung der Funktionsparameter führen könnte. Es sind daher weitere epidemiologische und klinische Studien notwendig, um den komplexen Zusammenhang zwischen K- und Mg-Intake und Beeinflussung der Lungenfunktionsparameter zu evaluieren.

  19. Diagnostik und Therapie der Interstitiellen Zystitis

    Directory of Open Access Journals (Sweden)

    Riedl CR

    2003-01-01

    Full Text Available Das Hauptproblem und wesentliches Hindernis für eine kompetente Diagnostik und Therapie der interstitiellen Zystitis (IC stellt immer noch die mangelnde Berücksichtigung des stadienhaften und progressiven Verlaufs dieser Erkrankung dar. Während die Diagnose "Interstitielle Zystitis" für das Endstadium mit therapieresistentem Harndrang, unerträglichen Schmerzen und Schrumpfblase bereitwillig akzeptiert und gestellt wird, sind die über viele Jahre mäßig symptomatischen Vorstadien bisher nicht ausreichend beachtet worden. Wer sich mit dem Krankheitsbild der interstitiellen Zystitis intensiv beschäftigt, weiß, daß die Betroffenen eine lange Krankheitsgeschichte hinter sich haben, bevor schließlich keine therapeutische Maßnahme mehr die Beschwerden bessert und unbehandelbare Invalidität eintritt. Die therapieresistente Reizblase als Frühstadium ist in der Vergangenheit kaum mit dem Krankheitsbild der interstitiellen Zystitis in Zusammenhang gebracht worden. Erst durch die Arbeiten Hohlbruggers, der die normale Blasenphysiologie untersuchte und die komplexen Zusammenhänge bei der Drangentstehung und der Blasenentleerung erklärte, wurde ein Verständnis der Pathophysiologie der interstitiellen Zystitis geschaffen, das es uns heute ermöglicht, Krankheitsfrühstadien zu erkennen und auch weit vor Erreichen der von Hunner und Bumpus schon vor fast einem Jahrhundert beschriebenen Endstadien zu heilen.

  20. Antikoagulation nach Venenthrombosen und Pulmonalembolien

    Directory of Open Access Journals (Sweden)

    Eichinger S

    2013-01-01

    Full Text Available Die venöse Thromboembolie (VTE ist eine häufige und chronische Erkrankung mit hohem Rezidivrisiko. Ein Rezidiv kann durch eine Antikoagulantientherapie verhindert werden, die jedoch ein Blutungsrisiko mit sich bringt. Die optimale Dauer der Antikoagulation leitet sich daher vom Verhältnis des Rezidivrisikos zum Blutungsrisiko ab. Patienten mit einer VTE, die im Zusammenhang mit einem transienten Risikofaktor aufgetreten ist, haben ein niedriges Rezidivrisiko. In diesen Fällen ist eine 3-monatige Antikoagulation ausreichend, da sonst das Risiko der Blutung das des Rezidivs überwiegen würde. Patienten mit einer spontanen VTE haben ein höheres Rezidivrisiko und eine lang dauernde Antikoagulation sollte erwogen werden. Die meisten dieser Patienten werden dennoch kein Rezidiv erleiden. Es ist derzeit jedoch nicht möglich, Patienten mit einem hohen oder niedrigen Rezidivrisiko sicher voneinander zu unterscheiden. Mithilfe von Vorhersagemodellen könnte das Rezidivrisiko auch bei Patienten mit spontaner VTE besser abgeschätzt und somit die Entscheidung über die optimale Dauer der Antikoagulation verbessert werden. Neue orale Antikoagulantien und auch Aspirin wurden für die Behandlung von Patienten mit VTE überprüft. Zusätzliche Daten vor allem über das Blutungsrisiko sind notwendig, um zu entscheiden, welche Patienten nun tatsächlich von diesen neuen Substanzen profitieren könnten.

  1. Molekulargenetische und archäologische Untersuchungen zur Domestikation und Züchtung des Schweins (Sus scrofa)

    OpenAIRE

    Krause-Kyora, Ben

    2011-01-01

    Die Arbeit behandelt die Domestikation der Stammart des europäischen Wildschweins (Sus scrofa) und den Beginn und Umsetzung der Schweinehaltung im nordmitteleuropäischen Raum mit Hilfe von archäologischen und genetischen Analysemethoden.

  2. [Geisteswissenschaft und Publizistik im Baltikum des 19. und frühen 20. Jahrhunderts] / Manfred von Boetticher

    Index Scriptorium Estoniae

    Boetticher, Manfred von, 1947-

    2012-01-01

    Arvustus: Geisteswissenschaft und Publizistik im Baltikum des 19. und frühen 20. Jahrhunderts (Schriften der Baltischen Historischen Kommission, 17; Baltische Biographische Forschungen, 1). Hrsg. von Norbert Angermann, Wilhelm Lenz und Konrad Maier. (Berlin: LIT-Varlag, 2011)

  3. Development of research tool to evaluate the potential of using chlorella sorokiniana as bio-filter in recycled tilapia production

    OpenAIRE

    Latif, Muhammad Saqib

    2016-01-01

    The current study was attempted to develop the research tools in order to evaluate if Chlorella sorokiniana has a potential to perform as a bio-filter in recycle water tilapia production. The overall objective was to test the hypothesis that C. sorokiniana will effectively remove nitrogenous catabolites from the water and benefit the tilapia with oxygen and nutrients by photosynthesis. Removal of ammonia and nitrite from the water is improved by fertilization with phosphate, th...

  4. Modeling the biofiltration of dimethyl sulfide in the presence of methanol in inorganic biofilters at steady state.

    Science.gov (United States)

    Zhang, Yuefeng; Allen, D Grant; Liss, Steven N

    2008-01-01

    The presence of methanol (MeOH) improves DMS removal (up to 11-fold) by enhancing biomass growth in inorganic biofilters. Although the overall effect is positive, prolonged growth on methanol also negatively affects DMS degradation as a result of competition with DMS. The objectives of this study were to explore the potential to optimize DMS removal with methanol addition and to develop and experimentally validate a mathematical model describing the biofiltration of DMS in the presence of MeOH. Continuous experiments using three bench-scale biofilters packed with inorganic material were performed to examine the removal of DMS under different MeOH addition rates ranging from 0 to 140 g/m3/h. For a constant DMS loading of 3.5 g/m3/h, a maximum DMS removal rate of 1.8 g/m3/h was achieved at a MeOH addition rate of 20 g/m3/h in the inorganic biofilters. A steady-state model incorporating the competitive and activation effects of MeOH on DMS biodegradation was developed, and the modeled results on DMS and MeOH removal were in close agreement with experimental data. Both the experimental data and model simulation suggest that there is an optimum MeOH addition rate for a given DMS loading. A step-feeding strategy for MeOH addition was proposed and tested by the model to optimize DMS removal. The model-predicted results demonstrate that six-step feeding of MeOH enhances DMS treatment by 46% in the biofilters when compared to conventional feeding (one-step) of MeOH at the same total mass loading.

  5. Elimination of hydrophobic volatile organic compounds in fungal biofilters: reducing start-up time using different carbon sources.

    Science.gov (United States)

    Vergara-Fernández, Alberto; Hernández, Sergio; Revah, Sergio

    2011-04-01

    Fungal biofilters have been recently studied as an alternative to the bacterial systems for the elimination of hydrophobic volatile organic compounds (VOC). Fungi foster reduced transport limitation of hydrophobic VOCs due to their hydrophobic surface and extended gas exchange area associated to the hyphal growth. Nevertheless, one of their principal drawbacks is their slow growth, which is critical in the start-up of fungal biofilters. This work compares the use of different carbon sources (glycerol, 1-hexanol, wheat bran, and n-hexane) to reduce the start-up period and sustain high n-hexane elimination capacities (EC) in biofilters inoculated with Fusarium solani. Four parallel experiments were performed with the different media and the EC, the n-hexane partition coefficient, the biomass production and the specific consumption rate were evaluated. Biofilters were operated with a residence time of 1.3 min and an inlet n-hexane load of 325 g m(-3) (reactor) h(-1). The time to attain maximum EC once gaseous n-hexane was fed was reduced in the three experiments with alternate substrates, as compared to the 36 days needed with the control where only n-hexane was added. The shortest adaptation period was 7 days when wheat bran was initially used obtaining a maximum EC of 160 g m(-3) (reactor) h(-1) and a critical load of 55 g m(-3) (reactor) h(-1). The results were also consistent with the pressure drop, the amount of biomass produced and its affinity for the gaseous n-hexane, as represented by its partition coefficient.

  6. Leberversagen bei Sepsis und Multiorganversagen

    Directory of Open Access Journals (Sweden)

    Kapral C

    2005-01-01

    Full Text Available Eine Störung der Leberfunktion wird bei etwa 20–25% der Patienten mit Organversagen im Rahmen einer schweren Entzündungsreaktion beobachtet. Obwohl der klinische Parameter hierfür – der Anstieg des Bilirubins – in der Regel erst nach Funktionsstörungen anderer Organe auftritt, zeigen sehr sensitive Nachweismethoden einer hepatalen Dysfunktion wie die Indozyangrünclearance, daß die Leberbeteiligung ein sehr frühes Ereignis darstellt. Ursache für die Funktionseinschränkung der Leber sind vor allem Zytokine, die großteils direkt in der Leber selbst auf die verschiedenen Stimuli (Endotoxine, Hypoxie usw. freigesetzt werden. Spezifische Therapiemaßnahmen zur Verbesserung der Leberfunktion stehen dem Kliniker derzeit nicht zur Verfügung. Es gilt auch hier der Grundsatz, daß durch eine frühzeitige Herdsanierung und effektive Kreislauftherapie die Zytokinaktivierung möglichst gering gehalten werden soll, um damit auch Organtoxizitäten zu vermindern. Die zur Verfügung stehenden, kreislaufaktiven Substanzen zeigen eine individuell nur schwer voraussagbare, sehr unterschiedliche Wirkung auf Kreislauf und Funktion der Leber. Einzig Adrenalin dürfte aufgrund der vorliegenden Untersuchungen eine eher ungünstige Wirkung haben und sollte daher nicht zur Anwendung kommen. In der letzten Zeit konnten jedoch durch neue Maßnahmen erste klinische Erfolge nachgewiesen werden, bzw. im Tierexperiment eine Verbesserung der Leberfunktion beobachtet werden. So konnte durch Normalisierung der Blutzuckerkonzentration bei Patienten mit Sepsis eine Verbesserung der Mortalität und auch Verbesserung der mitochondrialen Funktion von Leberzellen beobachtet werden. Durch die Gabe von N-Acetylcystein wurde in Studien an kleinen Fallzahlen eine günstige Wirkung beobachtet, größere Studien werden hier Klarheit schaffen. Ebenfalls in klinischer Erprobung ist die orale Gabe von Gallensäuren, die den Gallensäuregehalt des Darmes erhöhen und damit die

  7. Recht und Rechtssystem als globale Struktur und Medium der Verhaltensorientierung / Raul Narits

    Index Scriptorium Estoniae

    Narits, Raul, 1952-

    2008-01-01

    Äratr.: Multiple Modernität, Globalisierung der Rechtsordnung und Kommunikationsstruktur der Rechtssysteme : Internationales Symposium zur Theorie der Rechtskommunikation an der Universität Tartu im April 2006 ; II. Sonderheft Estland. Berlin, 2008, lk. 219-238. - (Rechtstheorie : Zeitschrift für Logik und Juristische Methodenlehre, Rechtsinformatik, Kommunikationsforschung, Normen- und Handlungstheorie, Soziologie und Philosophie des Rechts ; Bd. 38, 2007, H. 2/3)

  8. Simulationen zur Compton-Kamera und Entwicklung zweier Absorptionsdetektoren auf Halbleiter- und Szintillatorbasis

    OpenAIRE

    Uhlmann, Norman

    2005-01-01

    Die Compton-Kamera bietet in der Zukunft in der Emissionstomographie neben PET und SPECT als drittes bildgebendes Verfahren aufgrund der Effizienz und der Dosiseinsparung ein großes Potential. Die vom Patienten emittierten Photonen werden in dem ersten Detektor durch eine Comptonwechselwirkung gestreut und in einem weiteren Detektor absorbiert. Aus der in dem Streudetektor deponierten Energie und den beiden Wechselwirkungsorten kann der Startort des Photons auf einen Kegelmantel begrenzt werd...

  9. Filmrezeptionen und Wertorientierungen Jugendlicher : thematischer Bericht zur Studie: Kunstrezeption und Wertorientierungen Jugendlicher

    OpenAIRE

    Wiedemann, Dieter

    1980-01-01

    Der vorliegende Bericht des Zentralinstitutes für Jugendforschung stellt wesentliche Ergebnisse zur Bedeutung der Freizeittätigkeit Spielfilmrezeption für junge Werktätige und Studenten der DDR dar. Er ist Teil der Studie "Kunstrezeption und Wertorientierungen Jugendlicher". Folgende Themenkomplexe werden untersucht: (1) Zur Bedeutung des Kinobesuchs im Rahmen ausgewählter Freizeittätigkeiten Jugendlicher: Beliebtheit und Häufigkeit von Kinobesuchen; (2) zur Nutzung und Bewertung ausgewählter...

  10. Geschmackspapillendichte und Geschmackswahrnehmung bei Jugendlichen mit Essstörungen und einer gesunden Kontrollgruppe

    OpenAIRE

    Kaltenhofer, Alice

    2009-01-01

    Fragestellung Die Schmeckwahrnehmung wird u.a. über Lernprozesse, kognitive Vorgänge, genetische und biochemische Faktoren reguliert. Ess- und Diätverhalten werden durch sie beeinflusst. Den anatomisch und physiologisch ersten Abschnitt der Schmeckwahrnehmung bilden die fungiformen Geschmackspapillen. In den Geschmackspapillen liegen die Geschmacksknopsen, mit deren Hilfe die Schmeckstoffe aufgenommen und in Form von Aktionspotentialen zum Thalamus, dem limbischen System,dem Gyrus postzentral...

  11. Identifizierung und Charakterisierung von Genen mit Einfluss auf Entwicklung und Erhalt des Knorpel-/Knochen-Systems

    OpenAIRE

    Tagariello, Andreas

    2006-01-01

    Defekte bei Bildung, Wachstum und Homöostase des Skeletts sind verantwortlich für eine Reihe menschlicher Erkrankungen, zu denen neben zahlreichen Skelettdysplasien und Kraniosynostosen auch Osteoarthrose und rheumatoide Arthritis gehören. Da die diesen Erkrankungen zugrunde liegenden molekularen Prozesse nur in Ansätzen aufgeklärt sind, war es Ziel der Arbeit, neue Gene, die in die komplexen Prozesse der Knorpel-/Knochenbildung, -differenzierung und -homöostase beim Menschen involviert sind,...

  12. A laboratory-scale comparison of compost and sand--compost--perlite as methane-oxidizing biofilter media.

    Science.gov (United States)

    Philopoulos, Andrew; Ruck, Juliane; McCartney, Daryl; Felske, Christian

    2009-03-01

    Municipal solid waste landfills produce methane, a potent greenhouse gas. A treatment approach is to passively vent landfill gas through a methane-oxidizing biofilter medium, a porous substrate that facilitates the growth of methanotrophic bacteria. Two substrates, compost and a sand-compost-perlite (SCP) mixture, were evaluated in a laboratory-scale experiment for their suitability as biofilter media. The SCP mixture was investigated to minimize settlement and was based on a particle size distribution specification used for turf grass. The long-term (218 days) methane removal rates showed that both compost and SCP were capable of removing 100% of the methane influent flux (134 g CH(4) m( -2) day(-1)). The post-experiment analysis showed that compost had compacted more than SCP. This did not affect the results; however, in a field installation, traffic on the biofilter surface (e.g. maintenance) could cause further compaction and negatively affect performance. Exopolymeric substance produced by the methanotrophic bacteria, attributed by others for declining removal rates due to bio-clogging, was not observed to affect the results. The maximum exopolymeric substance values measured were 23.9 and 7.8 mg D-glucose g(-1) (dry basis) for compost and SCP, respectively.

  13. Reduction of toxic products and bioaerosol emission of a combined ultraviolet-biofilter process for chlorobenzene treatment.

    Science.gov (United States)

    Wang, Can; Xi, Jin-Ying; Hu, Hong-Ying

    2009-04-01

    A combined process involving ultraviolet (UV) photodegradation and biofiltration was developed to treat gaseous chlorobenzene. The toxicity of the photodegradation products and the bioaerosol emissions from the biofilter were investigated. The experimental results showed that a standalone UV photodegradation of chlorobenzene can result in products having significant acute toxicity and genotoxicity, whereas a biofiltration process can produce a high concentration of bioaerosols, which are a potential health risk. In the combined process, the toxic products produced by the UV photodegradation were removed by the subsequent biofilter. The acute toxicity of the products was reduced from 0.042 to 0.005 mg zinc/mg total organic carbon (TOC). Also the genotoxicity was reduced from 0.76 to 0.16 microg 4-nitroquinoline-N-oxide per milligram TOC. On the other hand, the bioaerosol concentration emitted from the biofilter decreased from 1.38 x 10(3) colony-forming units (CFU) x m(-3) (without UV pretreatment) to 60 CFU x m(-3) (with UV pretreatment), nearly the same as the background level of 40 CFU x m(-3). The significant decrease in bioaerosol emission might be due to a high concentration of ozone (50 mg x m(-3) or 25 parts per million by volume produced by the UV pretreatment. Hence, the UV photodegradation and biofiltration process exhibited synergistic effects. Also, the combined UV-biofiltration process was ecologically safer and exhibited a lower degree of infectivity as compared with standalone UV or biofiltration processes.

  14. Start-up and the effect of gaseous ammonia additions on a biofilter for the elimination of toluene vapors

    Energy Technology Data Exchange (ETDEWEB)

    Morales, M.; Revah, S. [UAM-Iztapalapa, Distrito Federal (Mexico). Dept. de Ingenieria de Procesos e Hidraulica; Auria, R. [ORSTOM, Los Morales (Mexico)

    1998-11-20

    Biotechnological techniques, including biofilters and biotrickling filters are increasingly used to treat air polluted with VOCs (Volatile Organic Compounds). In this work, the start-up, the effect of the gaseous ammonia addition on the toluene removal rate, and the problems of the heat accumulation on the performance of a laboratory scale biofilter were studied. The packing material was sterilized peat enriched with a mineral medium and inoculated with an adapted consortium (two yeast and five bacteria). Start-up showed a short adaptation period and an increased toluene elimination capacity (EC) up to a maximum of 190 g/m{sup 3}/h. This was related to increased CO{sub 2} outlet concentration and temperature gradients between the packed bed and the inlet (Tm-Tin). These events were associated with the growth of the microbial population. The biofilter EC decreased thereafter, to attain a steady state of 8 g/m{sup 3}/h. At this point, gaseous ammonia was added. EC increased up to 80 g/m{sup 3}/h, with simultaneous increases on the CO{sub 2} concentration and (Tm-Tin).

  15. Removal of nitrogen and phosphorus from the secondary effluent in tertiary denitrifying biofilters combined with micro-coagulation.

    Science.gov (United States)

    Wei, Nan; Shi, Yunhong; Wu, Guangxue; Hu, Hongying; Guo, Yumei; Wu, Yihui; Wen, Hui

    2016-01-01

    Effective control of nitrogen and phosphorus in secondary effluent can reduce or avoid the eutrophication of receiving water bodies. Two denitrifying biofilters (DNBFs) packed with different sizes of quartz sands combined with micro-coagulation were operated for simultaneous removal of nitrogen and phosphorus from the secondary effluent. The quartz sand size in one DNBF was 2-4 mm (DNBFS), and in the other was 4-6 mm (DNBFL). In both DNBFs, methanol was used as the electron donor and different organic carbon to nitrogen (C/N) ratios were applied. Under C/N ratios of 1.5, 1.25, and 0.75 g/g, the nitrate nitrogen (NO3(-)-N) removal percentages were 73%, 77%, and 50% in DNBFS, and 43%, 25%, and 21% in DNBFL; the effluent total phosphorus concentrations were 0.15, 0.14, and 0.18 mg/L in DNBFS, and 0.29, 0.35, and 0.24 mg/L in DNBFL. The performance of both biofilters was quite stable within a backwashing cycle. The NO3(-)-N reduction rates were 1.31, 1.10, and 0.48 mg/(L·min) in DNBFS, and 0.97, 0.27, and 0.10 mg/(L·min) in DNBFL. For biomass detached from both biofilters, their denitrifying activities were similar. Biofilm biomass in DNBFS was higher than that in DNBFL, inducing a high denitrification efficiency in DNBFS.

  16. Biofilter design for effective nitrogen removal from stormwater - influence of plant species, inflow hydrology and use of a saturated zone.

    Science.gov (United States)

    Payne, Emily G I; Pham, Tracey; Cook, Perran L M; Fletcher, Tim D; Hatt, Belinda E; Deletic, Ana

    2014-01-01

    The use of biofilters to remove nitrogen and other pollutants from urban stormwater runoff has demonstrated varied success across laboratory and field studies. Design variables including plant species and use of a saturated zone have large impacts upon performance. A laboratory column study of 22 plant species and designs with varied outlet configuration was conducted across a 1.5-year period to further investigate the mechanisms and influences driving biofilter nitrogen processing. This paper presents outflow concentrations of total nitrogen from two sampling events across both 'wet' and 'dry' frequency dosing, and from sampling across two points in the outflow hydrograph. All plant species were effective under conditions of frequent dosing, but extended drying increased variation between species and highlighted the importance of a saturated zone in maintaining biofilter function. The saturated zone also effectively treated the volume of stormwater stored between inflow events, but this extended detention provided no additional benefit alongside the rapid processing of the highest performing species. Hence, the saturated zone reduced performance differences between plant species, and potentially acts as an 'insurance policy' against poor sub-optimal plant selection. The study shows the importance of biodiversity and inclusion of a saturated zone in protecting against climate variability.

  17. Performance of double-layer biofilter packed with coal fly ash ceramic granules in treating highly polluted river water.

    Science.gov (United States)

    Jing, Zhaoqian; Li, Yu-You; Cao, Shiwei; Liu, Yuyu

    2012-09-01

    To improve trickling filters' denitrification efficiency, a biofilter with a trickling upper layer and a submerged lower layer was developed and applied in treating highly polluted river water. It was packed with porous coal fly ash ceramic granules. Its start-up characteristics, influence of hydraulic loading rates (HLR), carbon/nitrogen (C/N) ratio and filter depth on pollutants removal were investigated. The results indicated this biofilter was started quickly in 16 days with river sediment as inoculum. Alternating nitrification and denitrification were achieved when water flowed downwards. COD and nitrogen were mainly removed in the upper layer and the lower layer, respectively. With HLR of 4.0-5.0m(3)/(m(2)d), chemical oxygen demand (COD), ammonium (NH(4)(+)-N) and total nitrogen (TN) in the effluent were below 50, 5 and 15 mg/L, respectively. This biofilter removed more than 80% of COD, 85% of NH(4)(+)-N and 60% of TN with C/N ratios ranging from 6 to 10.

  18. Herstellung und Charakterisierung von Kombinationen aus Mannit und Sorbit durch Sprühtrocknung und Co-Granulation

    OpenAIRE

    Bauer, Heike

    2000-01-01

    Ziel der Arbeit ist es, eine Polyolkombination aus Mannit und Sorbit herzustellen und die Parameter für den Granulationsprozess festzulegen, unter denen eine nadelförmige Struktur auf der Partikeloberfläche entsteht. Eine gegenseitige Beeinflussung der beiden Komponenten sowie auftretende Polymorphie wird an physikalischen Mischungen und co-sprühgetrockneten Produkten untersucht. Es entstehen weder Co-Kristalle noch ein Eutektikum. Die Polyole kristallisieren nebeneinander aus. Sorbit fällt h...

  19. Zoophilie in Zoologie und Roman: Sex und Liebe zwischen Mensch und Tier bei Plutarch, Plinius dem Älteren, Aelian und Apuleius

    Directory of Open Access Journals (Sweden)

    Judith Hindermann

    2011-09-01

    Full Text Available Die Bedeutung von Zoophilie in der antiken Literatur wurde bislang – mit Ausnahme des Mythos – kaum untersucht. Überblickt man die überlieferten literarischen Texte, fällt auf, dass Zoophilie ausserhalb des Mythos vor allem in zwei literarischen Gattungen auftritt : Einerseits in den zoologischen Schriften von Plutarch, Plinius dem Älteren und Aelian, andererseits im antiken Roman, d.h. in den Metamorphosen des Apuleius und im pseudo-lukianischen Onos. In diesem Beitrag soll untersucht werden, welche Funktion Zoophilie in den beiden literarischen Gattungen hat und wie die Autoren die sexuelle Praktik bewerten, die weder nach griechischem noch römischen Recht strafbar war. Da Vorstellungen über Tiere eng mit Gender und Geschlechterhierarchien verbunden sind, soll insbesondere die Frage berücksichtigt werden, inwiefern männliche und weibliche Verhaltens- und Rollenzuschreibungen bei der Darstellung zoophiler Akte wirksam werden.

  20. Gute Inhalte produzieren und Rahmen schaffen

    DEFF Research Database (Denmark)

    Pogner, Karl-Heinz

    2004-01-01

    für den Dialog genutzt werden. Bei der Nutzung digita-ler Kommunikationsformen dominiert die E-Mail. Andere Medien wie Homepages oder TV/Film werden, je nachdem, ob sie der internen oder der externen Kommunikation dienen, als unterschied-lich bedeutsam gewertet. Bei den Mitarbeiterqualifikationen...... Informationschefs sowie Kommunikationsberater wurden befragt zu: Kommunikati-onsstrategie, Nutzung digitaler Kommunikationsformen und gewünschte Mitarbeiterqualifikationen (2, 3). Die wichtigsten Ergebnisse lauten: Das Intranet soll besser strukturiert und vereinfacht wer-den, ausserdem soll es vermehrt als Forum...... stehen persönliche und soziale Kompe-tenzen sowie Vermittlungsfähigkeiten und -fertigkeiten im Vordergrund, nicht technisches Spezia-listentum. Handwerkliches Können bei der Produktion von Texten und anderen Kommunikations-inhalten sowie generelles Wissen über Vor- und Nachteile der einzelnen Medien...

  1. Prophylaxe und Therapie der Venenthrombose und Pulmonalembolie während der Schwangerschaft und im Wochenbett

    Directory of Open Access Journals (Sweden)

    Eichinger S

    2010-01-01

    Full Text Available Die Schwangerschaft und besonders die Zeit des Wochenbetts gehen mit einem erhöhten Risiko für Venenthrombosen und Pulmonalembolien einher. Für Frauen, die noch nie eine venöse Thromboembolie (VTE durchgemacht haben, gibt es keine generelle Indikation für eine medikamentöse Primärprophylaxe. Auch nach einer Schnittentbindung liegen keine Daten aus kontrollierten Studien vor, die für eine routinemäßige Thromboseprophylaxe sprechen, dennoch ist diese in vielen europäischen Ländern geübte Praxis. Frauen, die bereits vor der Schwangerschaft eine VTE durchgemacht haben, wird die Gabe eines niedermolekularen Heparins für die gesamte Dauer der Schwangerschaft und für einige Wochen post partum empfohlen. Zur Behandlung einer akuten VTE während der Schwangerschaft steht nur (niedermolekulares Heparin zur Verfügung, da alle anderen Antikoagulantien in dieser Situation entweder kontraindiziert oder nicht zugelassen sind. Wird niedermolekulares Heparin in therapeutischer Dosierung verabreicht, sollte die Dosis wenn möglich peripartal reduziert werden, um Blutungskomplikationen zu vermeiden und eine rückenmarksnahe Anästhesie zu ermöglichen.

  2. Philologie im Horizont der Geschichtlichkeit von Sprache und Text: zum Tagungsband von Wulf Oesterreicher und Maria Selig

    Directory of Open Access Journals (Sweden)

    Olaf Müller

    2016-03-01

    Full Text Available Wulf Oesterreicher und Maria Selig, Hrsg., Geschichtlichkeit von Sprache und Text: Philologien – Disziplingenese – Wissenschaftshistoriographie (Paderborn: Wilhelm Fink, 2014, 332 S.

  3. Biofiltração da água e tipos de substrato na larvicultura do pacamã Water biofilter system and biofilter media on pacamã larviculture

    Directory of Open Access Journals (Sweden)

    Marcelo Mattos Pedreira

    2009-05-01

    Full Text Available O objetivo deste trabalho foi avaliar o uso de diferentes biofiltros e substratos na qualidade da água e no desempenho de larvas de Lophiosilurus alexandri. Os tratamentos usados foram: sistema sem biofiltro (SB; biofiltro interno ao tanque com substrato de cascalho de diâmetro médio de 1,6 cm (CMe; biofiltro interno ao tanque com cascalho de diâmetro médio de 2,1 cm (CMa; biofiltro interno ao tanque com substrato constituído de uma mistura de 70% de brita (diâmetro médio de 1,3 cm e 30% de concha (diâmetro médio de 1,1 cm (CB; e sistema fechado (SF com biofiltro externo aos tanques, com substrato de brita e concha. O experimento foi realizado em delineamento inteiramente casualizado, com cinco tratamentos e cinco repetições, durante 16 dias. Para íon amônio, nitrito, nitrato e ortofosfato, houve interação entre sistemas x dias de cultivo. Os sistemas SF, CMe e CB registraram menores concentrações de íon amônio e nitrito; o sistema SB, maiores concentrações de íon amônio e menores concentrações de nitrato; o SF, concentrações de ortofosfato superiores. A sobrevivência de L. alexandri foi inferior no SF. O crescimento não foi afetado pelos diferentes sistemas. Os biofiltros melhoraram a qualidade da água quanto aos compostos nitrogenados emfunção do tipo de substrato.The objective of this work was to investigate the use of different biofilter systems and biofilter media on water quality and performance of Lophiosilurus alexandri larvae. The treatments used were: no biofilter system (SB; internal biofilter with 1.6 cm average diameter shingle media (CMe; internal biofilter with 2.1 cm average diameter shingle media (CMa; a mix of 70% of grit (1.3 cm average diameter and 30% of shell media (1.1 cm average diameter (CB; and a closed recirculating system with external biofilter with 70% grit and 30% shell media (SF. The experiment was carried out in a completely randomized design, with five treatments and five

  4. Zeitschriftenübersicht und Buchbesprechungen

    OpenAIRE

    1996-01-01

    Zeitschriftenübersicht und Buchbesprechungen: Oerter, R./Montada, L. (1995): Entwicklungspsychologie. Weinheim. Büttner, Ch. (1995): Gruppenarbeit - eine psychoanalytisch pädagogische Einführung. Mainz. Harnisch, G. (1995): Was Kinderträume sagen. Freiburg. Nissen, G. (Hrsg.) (1995): Angsterkrankungen - Prävention und Therapie. Bern. Vogt, M./Winizki, E. (1995): Ambulante Gruppentherapie mit Jugendlichen. Frankfurt a.M.. Gang, M. (Hrsg.) (1995): Ausbildung und Praxisfe...

  5. Von Medien, Übertragungen und Automaten

    Directory of Open Access Journals (Sweden)

    Alessandro Barberi

    2013-12-01

    Full Text Available Im Zuge der Debatten zum Medialen Habitus wurde vielfach betont, dass die >Theorie der Praxispraxeologischen Medientheorie< des Medialen Habitus avant la lettre gesprochen werden kann. Dieser Artikel untersucht – ausgehend von den Debatten zur "Medienkompetenz" – wie Bourdieu Sprache, Sprechen und Diskurs, sowie Akteure, Felder und Habitus als Medien begreift und betont dabei die Nützlichkeit der Bourdieuschen Bildungssoziologie im Rahmen einer sozialwissenschaftlichen Grundlegung der Medienpädagogik.

  6. Paul F. Lazarsfeld und die Geschichte

    OpenAIRE

    Wilke, Jürgen

    1989-01-01

    Paul F. Lazersfeld - einer der 'Gründungsväter' der empirischen Sozialforschung - ist in seinem Denken nicht so ahistorisch wie allgemein dargestellt. Der vorliegende Beitrag zeigt, daß Lazersfeld in verschiedener Weise und in verschiedenen Phasen durchaus historische Fragestellungen und Interessen entwickelt hat oder sie aus seiner Sicht zu befruchten suchte. Dies geschieht in drei Bereichen: (1) Lazersfeld geht den Ursprüngen der empirischen Sozialforschung bis ins 17.Jahrhundert nach und u...

  7. Digitale Medien, soziale Benachteiligung und soziale Distinktion

    Directory of Open Access Journals (Sweden)

    Horst Niesyto

    2009-06-01

    Full Text Available Der Beitrag zeigt auf, dass kulturtheoretische Ansätze zur Mediensozialisation die Relevanz unterschiedlicher sozialer Lebenslagen unterschätzten. Am Beispiel des Themas ‹Digital Divide› werden Forschungsbefunde auf dem Hintergrund des Spannungsfelds von sozialer Benachteiligung und sozialer Distinktion referiert und eingeordnet. Der abschliessende Teil entwickelt ein Verständnis von milieusensibler Medienkompetenzbildung, welches die Medienpraxis der Subjekte in Zusammenhang mit vorhandenen (inneren und äusseren Ressourcen zur Lebensbewältigung betrachtet.

  8. Campusnetz-Management - Stand und Ausblick

    OpenAIRE

    Schier, Thomas

    2002-01-01

    The lecture represents the current technologies and components of network management at Chemnitz University. Particularly the OSI layer 1, 2 and 3 are considered. The author gives a summary of completion and further developement. Gemeinsamer Workshop von Universitaetsrechenzentrum und Professur Rechnernetze und verteilte Systeme der Fakultaet fuer Informatik der TU Chemnitz. Der Vortrag stellt die aktuellen Technologien und Komponenten des Netzwerkmanagements an der TU Chem...

  9. Zystische Pankreastumoren: Klassifikation und malignes Potenzial

    Directory of Open Access Journals (Sweden)

    Esposito I

    2011-01-01

    Full Text Available Zystische Pankreastumoren, obwohl insgesamt selten, haben an Bedeutung zugenommen, da sie zu den gut diagnostizierbaren, gut behandelbaren und prognostisch zumeist günstigen Tumoren des Pankreas gehören. Die Kenntnis der wichtigsten klinisch-pathologischen Charakteristika (Alters- und Geschlechtsverteilung, Lokalisation, Bezug zum Gangsystem, relative Häufigkeit erlaubt bereits eine präoperative Einordnung der zystischen Pankreastumoren in „Low"- und "High-risk"-Läsionen. Die postoperative morphologische und immunhistochemische Diagnostik vervollständigt die prognostische Stratifizierung und bestimmt die Nachsorge. Das Spektrum der zystischen Pankreasläsionen und -neoplasien ist groß, kann jedoch auf die 5 häufigsten Läsionen/Neoplasien (Pseudozyste, intraduktal papillär-muzinöse Neoplasie [IPMN], muzinös- zystische Neoplasie [MCN], serös-zystische Neoplasie [SCN] und solid-pseudopapilläre Neoplasie [SPN] beschränkt werden, da diese 95 % aller zystischen Pankreasprozesse ausmachen. Unter den Neoplasien sind die IPMN und MCN am wichtigsten. Sie zeigen eine Adenom-Karzinom- Sequenz, sodass die Resektion therapeutisch an erster Stelle steht. Bei den IPMN muss darüber hinaus eine Subtypisierung in Hauptund Seitengang-IPMN durchgeführt werden, da dadurch eine weitere prognostische Stratifizierung möglich ist. SPN und SCN sind niedrig maligne bzw. benigne Tumoren ohne große prognostische Probleme. Insgesamt gilt für die zystischen Läsionen und Neoplasien des Pankreas, dass ihre spezifische Behandlung eine genaue Klassifizierung und damit eine enge Zusammenarbeit zwischen Klinik und Pathologie verlangt.

  10. Topika und deren Einsatz in der Dermatologie.

    Science.gov (United States)

    Wohlrab, Johannes

    2016-11-01

    Grundkenntnisse zur Zusammensetzung und den regulatorischen Hintergründen von Topika gehören zu den alltäglich benötigten Herausforderungen dermatologisch-ärztlichen Handelns. Ein professioneller und indikationsgerechter Umgang bei der Auswahl, Verordnung und Anwendung topischer Präparate ist somit Voraussetzung für eine verantwortungsvolle fachärztliche Tätigkeit. Dabei bereiten die regulatorische Zuordnung (Arzneimittel, Medizinprodukt, Kosmetikum), die Feststellung der Erstattungsfähigkeit durch die GKV und die unzureichende Kennzeichnung des Vehikelsystems einzelner Präparate nicht selten Probleme. Bestreben sollte es sein, neben der Wahl des geeigneten Wirkstoffs und der geeigneten Konzentration ein an die Indikation der Therapie angepasstes galenisches System auszuwählen, um dessen Eigenwirkung für den therapeutischen Effekt nutzen zu können. Bei der Verschreibung von Rezepturarzneimitteln sollte nach Möglichkeit immer auf eine standardisierte Rezeptur (Magistralrezeptur) zurückgegriffen werden. Durch die Vielzahl der möglichen Inhaltsstoffe und der sich daraus ergebenden Komplexität eines galenischen Systems ist eine willkürliche Manipulation durch qualitative oder quantitative Veränderungen einzelner Komponenten mit hohen Risiken für eine Instabilität und damit für Sicherheit und Sinnhaftigkeit verbunden. Eine optimierte Anwendung von Topika setzt zudem Grundlagenkenntnisse zur Pharmakokinetik und zur evidenzbasierten Therapieplanung voraus.

  11. Schilddrüse und Schwangerschaft

    Directory of Open Access Journals (Sweden)

    Zettinig G

    2009-01-01

    Full Text Available Kinderwunsch, Schwangerschaft und die Zeit nach einer Geburt sind besondere Lebensabschnitte bei Patientinnen mit Schilddrüsenerkrankungen. Bei jungen Frauen sind Autoimmunerkrankungen der Schilddrüse, die Einfluss auf die Fruchtbarkeit und die intellektuelle und körperliche Entwicklung des Fetus haben können, häufig. Schilddrüsenerkrankungen können sich in dieser Lebensphase auch erstmals manifestieren; besondere Beachtung verdient die Wechselwirkung von β-HCG mit dem TSH-Rezeptor. Diese Übersicht behandelt das aktuelle Management von Patientinnen mit Schilddrüsenerkrankungen bei Kinderwunsch, in der Schwangerschaft und Postpartalperiode.

  12. Experimentalphysik 4 Kern-, Teilchen- und Astrophysik

    CERN Document Server

    Demtröder, Wolfgang

    2013-01-01

    Band 4 des Lehrbuchs zur Experimentalphysik beinhaltet den Stoff des vierten Semesters im Physikstudium. So wie bei den ersten drei Bänden auch präsentiert der Autor die Inhalte leicht verständlich, dabei möglichst quantitativ und angepasst an den Bachelor-Studiengang. Durchgerechnete Beispiele und Übungsaufgaben mit ausführlichen Lösungen helfen dabei, den Stoff zu bewältigen und regen zum Mitdenken an. Die vollständig überarbeitete Neuauflage wurde um Abschnitte u. a. zum LHC-Beschleuniger, zu extrasolaren Planeten und dunkler Materie erweitert.

  13. Getrieben oder Gestalter in Marketing und Vertrieb?

    OpenAIRE

    Belz, Christian; Lee, You-Cheong

    2014-01-01

    Fühlen sich die Manager in Marketing und Vertrieb als Gestalter oder Getriebene? Was tun Führungskräfte in Marketing und Vertrieb wirklich und wo setzen sie Schwerpunkte in ihrer Aufgabe? Wie nutzen sie ihre Zeit? Diese Fragen beantworten wir, gestützt auf eine Online-Erhebung im 1. Quartal 2013. 135 Führungskräfte beteiligten sich, davon waren 38,5 Prozent für Marketing, 23 Prozent für Vertrieb und 38,5 Prozent für beide Funktionen zuständig. Das Ergebnis: Verantwortliche in Marketin...

  14. Deutsche Modalpartikeln und chinesische Yuqi-Ci

    Institute of Scientific and Technical Information of China (English)

    于豪

    2010-01-01

    @@ Meistens wird Chinesisch als eine isolierende Sprache betrachtet,weil es keine rechte Grammatik in Europaer's Sinn gibt und sehr begriffsorientiert ist.Es ist ideographisch,d.h.jedem Begriff ist ein Schriftzeichen zugeordnet.Besonders hinsichtlich der Morphologie und der Syntax weisen Deutsch und Chinesisch nur ganz wenige Vergleichsmoglichkeiten auf.Trotzdem gibt es solche Wortart zwischen beiden Sprachen,nahmlich Modalpartikle,die er-staunlichen A hnlichkeiten haben und sich ziemlich gut miteinander vergleichen lassen konnen.Obwohl die Anzahl derartigen Untersuchungen insgesamt jedoch eher gering ist,scheint eine kontrastive Analyse nicht nur moglich,sondem auch sinnvoll zu sein.

  15. Editorial: Theoriebildung in Mediendidaktik und Wissensmanagement

    Directory of Open Access Journals (Sweden)

    Michael Kerres

    2002-10-01

    Full Text Available Das Internet trägt massgeblich zur Entstehung einer neuen Lern- und Wissenskultur bei und ist mittlerweile Gegenstand einer ganzen Reihe von Projekten in der Erziehungswissenschaft. So wird zum Beispiel der Frage nachgegangen, welche Möglichkeiten der Strukturierung und Gestaltung von Lernmaterialien am besten geeignet sind, um Lernprozesse anzuregen, wie die interpersonale Kommunikation im Internet durch didaktische Gestaltungsmassnahmen gefördert werden können oder wie die entfernte Betreuung von Lernenden über das Netz funktioniert. Zunehmend wird dabei auch der Übergang bedeutsam zwischen didaktisch aufbereiteten Lernangeboten, wie sie die Mediendidaktik traditionell beschäftigt, und dem Austausch von nicht didaktisch aufbereiteten Informationen in Organisationen, wie es im Bereich des Wissensmanagements diskutiert wird. In diesen Projekten werden vielfach Detailfragen behandelt, und isoliert, ohne Bezug zu grundlegenden Theoriefragen untersucht. Es mangelt an einer genuin mediendidaktischen Theoriediskussion, die einen übergreifenden Bezugsrahmen aus erziehungswissenschaftlicher Perspektive liefert. In der Vergangenheit ist die Mediendidaktik von Seiten einer «kritischen» Medienpädagogik zeitweise skeptisch beäugt und in ihrer Existenz grundlegend infrage gestellt worden. In der aktuellen Diskussion wird gerne auf lerntheoretische Ansätze zurückgegriffen, die Lernen als aktiven Vorgang der individuellen und kooperativen Wissenskonstruktion begreifen. Doch Wissens- und Lerntheorien ersetzen keine mediendidaktische Modell- und Theoriebildung, die Perspektiven für eine Gestaltung zukünftiger Lernwelten liefert und dabei zum Beispiel sowohl bildungstheoretische Überlegungen als auch Konzepte des instructional design einbezieht. In dem ersten Teil dieser Ausgabe geht es um theoretische Perspektiven der Mediendidaktik. So diskutiert der Artikel von Michael Kerres und Claudia de Witt den Beitrag der Positionen von Behaviorismus

  16. Autotrophic Biofilters for Oxidation of Nitric Oxide%自养型生物过滤器硝化氧化一氧化氮

    Institute of Scientific and Technical Information of China (English)

    陈建孟; 陈浚; L.Hershman; 王家德; D.P.Y.Chang

    2004-01-01

    Carbon foam-a kind of new engineering material as packing material was adopted in three biofilters with different pore dimensions and adapted autotrophic nitrite nitrobacteria to investigate the purification of nitric oxide (NO) in a gas stream. The biofilm was developed on the surface of carbon foams using nitrite as its only nitric source. The moisture in the filter was maintained by ultrasonic aerosol equipment which can minimize the thickness of the liquid film. The liquid phase nitrification test was conducted to determine the variability and the potential of performance among the three carbon foam biofilters. The investigation showed that during the NO-2-N inlet concentration of 200 g-L-1 .min-1 to 800 g-L-1 .min-1, the 24PPC (pores per centimeter) carbon foam biofilter had the greatest potential, achieving the NO-2-N removal efficiency of 94% to 98%. The 8PPC and 18PPC carbon foam biofilters achieved the NO-2-N removal efficiency of 15% to 21% and of 30% to 40%, respectively. The potential for this system to remove NO from a gas stream was shown on the basis of a steady removal efficiency of 41% to 50% which was attained for the 24PPC carbon foam biofilter at specified NO inlet concentration of 66.97mg.m-3to 267.86 mg.m-3 and an empty-bed residence time of 3.5 min.

  17. Comparison between conventional biofilters and biotrickling filters applied to waste bio-drying in terms of atmospheric dispersion and air quality.

    Science.gov (United States)

    Schiavon, Marco; Ragazzi, Marco; Torretta, Vincenzo; Rada, Elena Cristina

    2016-01-01

    Biofiltration has been widely applied to remove odours and volatile organic compounds (VOCs) from industrial off-gas and mechanical-biological waste treatments. However, conventional open biofilters cannot guarantee an efficient dispersion of air pollutants emitted into the atmosphere. The aim of this paper is to compare conventional open biofilters with biotrickling filters (BTFs) in terms of VOC dispersion in the atmosphere and air quality in the vicinity of a hypothetical municipal solid waste bio-drying plant. Simulations of dispersion were carried out regarding two VOCs of interest due to their impact in terms of odours and cancer risk: dimethyl disulphide and benzene, respectively. The use of BTFs, instead of conventional biofilters, led to significant improvements in the odour impact and the cancer risk: when adopting BTFs instead of an open biofilter, the area with an odour concentration > 1 OU m(-3) and a cancer risk > 10(-6) was reduced by 91.6% and 95.2%, respectively. When replacing the biofilter with BTFs, the annual mean concentrations of odorants and benzene decreased by more than 90% in the vicinity of the plant. These improvements are achieved above all because of the higher release height of BTFs and the higher velocity of the outgoing air flow.

  18. Isolierung, Charakterisierung und Lokalisierung der ATP-Synthasen der archaeellen Genera Ignicoccus und Nanoarchaeum

    OpenAIRE

    Kreuter, Lydia Juliane

    2015-01-01

    Im Rahmen dieser Arbeit konnte ein Proteinkomplex aus I. hospitalis chromatographisch gereinigt werden, der alle Untereinheiten der ATP-Synthase/ATPase enthielt. Jedoch erwies sich dieser als sehr instabil, was unter anderem während der nativen Gelelektrophorese und der Gelfiltration deutlich wurde. Er zerfiel dabei in zwei Subkomplexe von etwa 440 kDa und 669 kDa, von denen der erste die Untereinheiten A, B, E und vermutlich F und der zweite die Untereinheiten a, c, H sowie vermutlich C und ...

  19. Städtische Diskurse um Migration im Wandel. Integration, diversity und soziale Bewegungen in München und Berlin

    Directory of Open Access Journals (Sweden)

    Natalie Bayer

    2014-12-01

    Full Text Available Sowohl im Kontext der kommunalen Integrationspolitik als auch in der Stadtplanung, der Repräsentationspolitik und der regionalen Standort- und Wirtschaftspolitik ist das Thema ,Migration in den Städten‘ wieder auf die politische Agenda gesetzt worden. Doch der Gegenstand, die theoretischen Konzeptualisierungen und die Perspektivierungen sind oft uneindeutig und politisch umkämpft. Gerade auf stadtpolitischer Ebene haben sich zudem starke migrantische Organisationen und Proteste formiert, die oftmals in neuen Allianzen agieren und sich hegemonialen Vorstellungen von ,Integration‘ und ,sozialer Mischung‘ verweigern. Ein Fachgespräch zwischen Natalie Bayer, Andrej Holm und Henrik Lebuhn über städtische Migrationspolitiken in München und Berlin sowie über Fragen und Probleme, die sich auf diesem Feld an der Schnittstelle zwischen kritischer Wissenschaft und praktischer Politik ergeben.

  20. Editorial 01/2013 Normen und Normierungen

    Directory of Open Access Journals (Sweden)

    Christian Swertz

    2013-03-01

    Full Text Available Auf unterschiedlichsten Ebenen werden die Diskussionen und Forschungen der Medienpädagogik von normativ aufgeladenen Begriffen durchzogen: so, wenn es um Standards in der Medienbildung geht, wenn beispielsweise diskutiert wird, welche Inhalte in welcher Form vermittelt werden sollen; so auch wenn zur Debatte steht, wie Medienpädagogik institutionalisiert werden sollte und welche Voraussetzungen gegeben sein müssen, um einen geplanten Bildungsprozess zu lenken oder anzuleiten.Derartige Norm(ierungen wurden bereits mit der Konzeptualisierung des Begriffs Medienkompetenz und im Blick auf die Emanzipation des Menschen kritisch beleuchtet, womit auch Kritik an gesellschaftlichen Herrschafts- und Machtstrukturen verbunden war. Die Orientierung an der sozialwissenschaftlich verstandenen Emanzipation des Menschen ist allerdings in anderen pädagogischen Disziplinen durchaus umstritten. Gleichzeitig ist zu beobachten, dass die gesellschaftskritische Perspektive im medienpädagogischen Diskurs über die Orientierung von Medienkompetenz und Medienbildung eine immer geringere Rolle spielt. Deshalb hat sich die Redaktion der MEDIENIMPULSE entschlossen, dem Thema Normen und Normierungen eine eigene Ausgabe zu widmen.Dabei sollten folgende Fragen behandelt werden:Wie sieht es mit Norm(ierungen im Bereich der Mediendidaktik aus? Wie sind die mit aktuellen Medienkompetenz- und Medienbildungsbegriffen verbundenen Normen epistemologisch und (medientheoretisch abgestützt? Wie lassen sich – nur scheinbar paradox formuliert – wissenschaftlich begründbare medienpädagogische Normen finden, die sich den genannten Normierungen widersetzen und entziehen? Inwiefern führt die Einführung von Laptopklassen oder Smartboards im schulischen Bereich oder die Gestaltung von Videospielprojekten in der außerschulischen Medienbildung zu einer unreflektierten Sozialdisziplinierung, die als illegitime Form(atierung des Menschen verstanden werden kann? Der Schwerpunktteil

  1. Simultaneous removal of H2S and NH3 in biofilter inoculated with Acidithiobacillus thiooxidans TAS.

    Science.gov (United States)

    Lee, Eun Young; Cho, Kyung-Suk; Ryu, Hee Wook

    2005-06-01

    H2S and NH3 gases are toxic, corrosive and malodorous air pollutants. Although there are numerous well-established physicochemical techniques presently available for the treatment of these gases, the growing demand for a more economical and improved process has prompted investigations into biological alternatives. In biological treatment methods, H2S is oxidized to SO4(2-) by sulfur-oxidizing bacteria, and then NH3 is removed by chemical neutralization with SO4(2-) to (NH4)2SO4. Since the accumulated (NH4)2SO4 can inhibit microbial activity, it is important to utilize an effective sulfur-oxidizing bacterium that has tolerance to high concentrations of (NH4)2SO4 for the simultaneous removal of H2S and NH3. In this study, a sulfur-oxidizing bacterium with tolerance to high concentrations of (NH4)2SO4 was isolated from activated sludge and identified as Acidithiobacillus thiooxidans TAS. A. thiooxidans TAS could display its sulfur-oxidizing activity in a medium supplemented with 60 g.l(-1) (NH4)2SO4, even though its growth and sulfur-oxidizing activity were completely inhibited in 80 g.l(-1) (NH4)2SO4. When H2S alone was supplied to a ceramic biofilter inoculated with A. thiooxidans TAS, an almost 100% H2S removal efficiency was maintained until the inlet H2S concentration was increased up to 900 microl.l(-1) and the space velocity up to 500 h(-1), at which the amount of H2S eliminated was 810 g-S.m(-3).h(-1). However, when NH3 (50-500 microl.l(-1)) was simultaneously supplied to the biofilter with H2S, the maximum amount of H2S eliminated decreased to 650 g-S.m(-3).h(-1). The inhibition of H2S removal by low NH3 concentrations (50-200 microl.l(-1)) was similar to that by high NH3 concentrations (300-500 microl.l(-1)). The critical inlet H2S load that resulted in over 99% removal was determined as 400 g-S.m(-3).h(-1) in the presence of NH3.

  2. Zwei Thesen zur Beziehung zwischen Kunst, Sprache und Erkenntnis: Ernst Cassirer und Benedetto Croce.

    Directory of Open Access Journals (Sweden)

    Sarah Dessì Schmid

    2016-06-01

    Full Text Available Der Beitrag widmet sich – nach einer kurzen Rekonstruktion des intellektuellen Dialogs zwischen Ernst Cassirer und Benedetto Croce – der Sprache und ihrer autonomen oder abhängigen Beziehung zur Kunst: Die Gleichsetzung oder Unterscheidung von Linguistik und Ästhetik im Denken beider Autoren im Vergleich stellt hierbei das Zentrum der Untersuchung dar.Ihre Ablehnung einer instrumentalistischen Au fassung der Sprache und deren Interpretation als Aktivität des Geistes verbinden Croces und Cassirers Denken zweifellos. Ein fundamentaler Unterschied – und eines der Hauptargumente ihrer Kritik aneinander – besteht jedoch darin, dass Croce im Rahmen der von ihm genau begrenzten Zahl der Aktivitäten des Geistes die Sprache mit der Kunst identifiziert und ihr unter diesen eine hierarchisch ausgezeichnete Stellung zuweist, während Cassirer die Sprache als eine den anderen gleichwertige autonome Form aus der unabgeschlossenen Zahl symbolischer Formen ansieht.Durch eine Analyse der Begri fe ‚Intuition‘ oder ‚Anschauung‘ und ‚Ausdruck‘, ‚symbolische Form‘, ‚Individuum‘ und ‚Alterität‘ – aus der auch hervorgeht, wie unterschiedlich die Humboldtsche Vorlage von beiden Autoren interpretiert wird – wird sich zeigen, wie es gerade ihr verschiedenes Verständnis des Idealismus ist, welches die Sprach- und Kunsttheorien Cassirers und Croces voneinander trennt.

  3. [Vegetarische und vegane Ernährung bei Kindern - Stand der Forschung und Forschungsbedarf].

    Science.gov (United States)

    Keller, Markus; Müller, Stine

    2016-01-01

    Die Praxis vegetarischer Ernährungsformen ist in Deutschland im letzten Jahrzehnt deutlich angestiegen. Allerdings ist der Anteil vegetarischer und veganer Kinder dabei unbekannt. Studien mit Erwachsenen zeigen das präventive Potenzial, aber auch potenzielle Schwachstellen pflanzenbasierter Kostformen. Die Vorteile und Risiken einer vegetarischen bzw. veganen Ernährung im Kindesalter wurden bisher jedoch relativ selten untersucht. Außerdem lassen das unterschiedliche Alter der Kinder, das heterogene Studiendesign sowie die teilweise geringe Probandenzahl der Studien keine verbindlichen Aussagen zu. In dieser Übersichtsarbeit werden die Ergebnisse der wenigen Studien zu vegetarisch und vegan ernährten Kindern (veganer Kinder meist näher an den Empfehlungen der Fachgesellschaften als die Ernährung gleichaltriger Mischkostkinder. Ebenso wiesen vegetarisch und vegan ernährte Kinder eine höhere Zufuhr von und bessere Versorgung mit verschiedenen Vitaminen und Mineralstoffen auf. Häufiger zeigten sich jedoch Defizite bei Vitamin B12, Zink, Kalzium, Eisen und Vitamin D. Das Wachstum und die Entwicklung vegetarisch und vegan ernährter Kinder entsprachen weitgehend den Referenzstandards, wobei sie dazu tendierten, leichter, schlanker und (< 5 Jahren) auch kleiner zu sein. Aufgrund der unzureichenden Studienlage besteht erheblicher Forschungsbedarf zu den Auswirkungen einer vegetarischen und veganen Ernährung im Kindesalter.

  4. Teilchenphysik und Kosmologie eine Einführung in Grundlagen und Zusammenhänge

    CERN Document Server

    Treichel, Michael

    2000-01-01

    Als einführendes Lehrbuch in die Teilchenastrophysik konzipiert wendet sich dieses Werk an Studenten der Physik und Astronomie ab dem Vordiplom. Kurz und prägnant werden die Grundlagen der Relativitätstheorie und der Quantenmechanik vorgestellt, bevor das Standardmodell der Teilchenphysik erläutert und die Zusammenhänge mit den heutigen Fragen aus Astrophysik und Kosmologie hergestellt werden. Mathematisch elementarer als die meisten Einführungen in die Teilchenphysik eignet sich dieses Buch sowohl begleitend zu einer Kursvorlesung als auch zum Selbststudium. Besonderer Wert wird auf pädagogische Aspekte gelegt: im Vordergrund stehen Anschaulichkeit, eine am tatsächlichen Denkprozess orientierte Darstellung und die Ausgewogenheit zwischen theoretischen, experimentellen und interpretatorischen Aspekten der modernen Astroteilchenphysik.

  5. Steueroasen und Regulierungsoasen – Auswirkungen auf die Stabilität des Finanzmarkts und politische Implikationen

    Directory of Open Access Journals (Sweden)

    Michaela Schmidt

    2012-12-01

    Full Text Available In diesem Beitrag wird dargelegt, dass Steuer- und Regulierungsoasen nicht nur Steuerausfälle und Kapitalflucht ermöglichen, sondern auch eine Hauptursache für die Finanzkrise 2007/2008 waren und weiterhin die Stabilität des Finanzmarkts gefährden. Sie haben den Boden bereitet für das Aufkommen nicht regulierter Finanzinstitutionen, sogenannter Schattenbanken. Regulierungsoasen ermöglichen Finanzmarktakteuren eine Umgehung von Regulierungs- und Aufsichtsvorschriften und heizen den Wettbewerb um niedrige Regulierungsvorschriften maßgeblich an. Jeder Schritt zu einer finanzpolitischen Re-Regulierung von Steuer- und Regulierungsoasen sowie Schattenbanken ist ein aktiver Schritt zur Krisenvorbeugung und damit zum Schutz der ArbeitnehmerInnen vor den gewaltigen volkswirtschaftlichen Kosten von Finanzkrisen.

  6. Theorie und Praxis von Hochschulrankings

    OpenAIRE

    Hornbostel, Stefan

    2007-01-01

    Der Beitrag gibt einen Überblick über die theoretische Grundlage von Hochschulrankings, welche in der qualitativ stark differenzierten Hochschullandschaft in Deutschland entscheidend für öffentliche Reputationsurteile sein können. Ausgehend von einem formal gleichrangigen Institutionengefüge der Hochschullandschaft in Deutschland haben die Stichworte Profilbildung, Exzellenz und Wettbewerb in den letzten Jahren zunehmend an Bedeutung gewonnen. Der daraus resultierende große Informationsbedarf...

  7. Dichtung und Wahrheit zur Biomilch

    OpenAIRE

    2005-01-01

    Die Qualität von Biomilch sei nicht besser als diejenige von IP-Milch. Und Biotiere seien unterernährt. Mit diesen Aussagen wurde Professor Jürg Blum von der Universität Bern in den Medien zitiert. Seine Äusserungen gehen auf zwei Doktorarbeiten zurück. Das exakte Studium der Arbeit zeigt aber, dass diese Schlussfolgerungen nicht gezogen werden können.

  8. Kardiale Magnetresonanztomographie - Anatomie und Planung

    Directory of Open Access Journals (Sweden)

    Maier R

    2003-01-01

    Full Text Available Die Achsen des Herzens und der großen Gefäße liegen nicht in den drei Hauptebenen des Körpers, transversal (axial, frontal (koronal und sagittal. Um Schnittbilder zu erhalten, die den anatomischen Strukturen des Herzens gerecht werden, müssen daher auf die Hauptebenen ein- oder mehrfach gewinkelte Ebenen gewählt werden. Die damit gewonnenen Bilder entsprechen großteils den aus der Echokardiographie bekannten Ebenen. Die Untersuchungsplanung erfolgt anhand sogenannter Suchschnitte, die das Herz in den drei Hauptebenen des Körpers zeigen. Transversale Schnitte erlauben eine morphologische Beurteilung des ganzen Herzens. Abhängig von der Fragestellung können weitere Aufnahmen in verschiedensten Ebenen geplant werden. Zur Funktionsbeurteilung werden v. a. der linksventrikuläre Zweikammerblick, der Vierkammerblick sowie die kurze Achse verwendet. Weiters können Schnitte in den Ebenen des links- bzw. rechtsventrikulären Ausflußtrakts sowie der aszendierenden bzw. LAO-Aorta geplant werden. Zur Untersuchung kongenitaler Herzfehler und der Koronarien sind spezielle Planungen notwendig.

  9. Erfahrungen an der Schnittstelle von Medienarbeit und Praxisforschung

    Directory of Open Access Journals (Sweden)

    Peter Holzwarth

    2007-11-01

    Full Text Available Der Beitrag reflektiert die Verbindung von praktischer Medienarbeit und Forschung am Beispiel eines internationalen EU-Forschungsprojekts zum Thema Medien und Migration. Neben didaktischen Prinzipien und Konzepten für die aktive Medienarbeit im Forschungskontext geht es um die Kooperation von medienpädagogischer Begleitung (MB und wissenschaftlicher Begleitung (WB sowie um deren spezifische Kompetenzen.

  10. [Sascha Möbius. Das Gedähtnis der Reichsstadt. Unruhen und Kriege in der lübeckischen Chronistik und Kriege und Erinnerungskultur des späten mittelalters und der frühen Neuzeit

    Index Scriptorium Estoniae

    Hormuth, Dennis

    2012-01-01

    Arvustus: Sascha Möbius. Das Gedähtnis der Reichsstadt. Unruhen und Kriege in der lübeckischen Chronistik und Kriege und Erinnerungskultur des späten mittelalters und der frühen Neuzeit. (Göttingen, 2011)

  11. Soziale Mission und Emanzipation. Zwei Pionierinnen der weiblichen Sozialarbeit

    Directory of Open Access Journals (Sweden)

    Margret Nitsche

    2006-03-01

    Full Text Available In einer umfangreichen Doppelbiographie beschreibt Anja Schüler Leben und Werk der beiden frühen Sozialreformerinnen und Feministinnen Jane Addams (1860-1935 und Alice Salomon (1872-1948 und die wechselseitige Rezeption ihrer jeweiligen sozialpolitischen Arbeit im transatlantischen Dialog.

  12. Sorption reactions in groundwater: various aspects to modelling the transport behaviour of zinc; Sorptionsreaktionen im Grundwasser: Unterschiedliche Aspekte bei der Modellierung des Transportverhaltens von Zink

    Energy Technology Data Exchange (ETDEWEB)

    Hadeler, A.

    1999-08-01

    The dispersal of trace substance in groundwater may be limited by dissolution and precipitation and, of particular interest in this paper, by sorption and desorption processes. These surface-active processes, which have a decisive influence on groundwater quality, depend on the concomitant geochemical conditions prevailing in the water, the constituents of the aquifer and on the surface properties of the solids. Taking the geochemical conditions prevailing naturally in brown coal mining areas as a point of departure this study was aimed at examining the influence of acidification processes on the transport behaviour inorganic pollutants for the example of zinc. For this purpose oxic column trials were carried out on sandy aquifer material. The data were supplemented by a detailed characterisation of the solid surfaces and modelled on the basis of a transport-reaction model as well as mechanistically with due regard to surface complexing. [German] Die Ausbreitung von Spurenstoffen im Grundwasser wird ausser durch Loesungs- und Faellungsprozesse vor allem durch Sorptions- bzw. Desorptionsvorgaenge limitiert. Diese fuer die Grundwasserqualitaet entscheidenden oberflaechenaktiven Prozesse sind von den variablen geochemischen Randbedingungen im Wasser, vom Stoffbestand des Aquifers und von den Oberflaecheneigenschaften der Feststoffe abhaengig. In Anlehnung an die natuerlichen im Bereich von Braunkohle-Abbaugebieten herrschenden geochemischen Bedingungen wurde der Einfluss von Versauerungsprozessen auf das Transportverhalten von anorganischen Schadstoffen, am Beispiel von Zink, auf der Basis von oxischen Saeulenversuchen an sandigem Aquifermaterial untersucht. Die Daten wurden durch eine detaillierte Charakterisierung der Feststoff-Oberflaechen ergaenzt und sowohl mit Hilfe eines Transport-Reaktionsmodells als auch mechanistisch unter Einbeziehung der Oberflaechenkomplexierung modelliert. (orig.)

  13. Systeme im Einsatz. Lernmanagement, Kompetenzmanagement und PLE

    NARCIS (Netherlands)

    Kalz, Marco; Schön, Sandra; Lindner, Martin; Roth, Detlev; Baumgartner, Peter

    2011-01-01

    Kalz, M., Schön, S., Lindner, M., Roth, D., & Baumgartner, P. (2011). Systeme im Einsatz. Lernmanagement, Kompetenzmanagement und PLE. In M. Ebner, & S. Schön (Eds.), L3T - Lerhbuch für Lernen und Lehren mit Technologie (pp. 111-118). Graz, Austria: Uni Graz. Available at http://l3t.tugraz.at/index.

  14. Nachhaltiger Lebensmittelkonsum gestern, heute und morgen

    DEFF Research Database (Denmark)

    Aschemann-Witzel, Jessica

    2013-01-01

    Die Weltgemeinschaft sieht sich mit steigendem Bevölkerungswachstum und Zielkonflikten der Nutzung von Land und Agrarrohstoffen konfrontiert. Dies wirft die Frage auf, wie nachhaltiger Lebensmittelkonsum in der Zukunft auszusehen hat. Der Beitrag diskutiert die Frage aus Sicht der Konsumverhaltens...

  15. E-Learning im Museum und Archiv

    NARCIS (Netherlands)

    Gruber, Marion

    2009-01-01

    Gruber, M. R. (2009). E-Learning im Museum und Archiv. Vermittlung von Kunst und Kultur im Informationszeitalter. Saarbrücken: VDM Verlag Dr. Müller. Available on http://www.amazon.de/E-Learning-Museum-Archiv-Vermittlung-Informationszeitalter/dp/3639204654/ref=sr_1_2?ie=UTF8&s=books&qid=1258383814&s

  16. Homocystein und Hyperhomocysteinämie

    Directory of Open Access Journals (Sweden)

    Kiefer I

    2001-01-01

    Full Text Available Homocystein ist ein Intermediärprodukt im Stoffwechsel schwefelhältiger Aminosäuren. Im gesunden Organismus wird Homocystein innerhalb von kurzer Zeit wieder zu Methionin remethyliert oder über Cystathionin und Cystein zu Glutathion weiter verstoffwechselt. Als Coenzyme werden die Vitamine B6 und B12 und als Methylgruppendonator die Folsäure benötigt. Homocystein ist ein unabhängiger Risikofaktor für eine Reihe von Erkrankungen wie beispielsweise Atherosklerose oder arterielle und venöse Thrombosen. Gesamtplasmaspiegel von 10 µmol/l stellen bereits ein Risiko für Begleit- und Folgekrankheiten dar. Jede Erhöhung des Plasmahomocysteinspiegels um bis zu 5 µmol/l erhöht das kardiovaskuläre Risiko zwischen 32 % und 60 % und entspricht einer Cholesterinerhöhung von 20 mg/dl. Schätzungen gehen davon aus, daß bis zu 7 % der Bevölkerung eine Homocysteinämie aufweisen, wovon zwei Drittel der Fälle wahrscheinlich auf eine unzureichende Plasmakonzentration der am Homocystein-Metabolismus beteiligten Vitamine (Folsäure, Vitamin B6 und Vitamin B12 zurückzuführen ist. Ziel muß es künftig sein, das Homocystein-Bewußtsein, sowohl in der Bevölkerung als auch bei den Ärzten zu erhöhen.

  17. China: Macht und die Sicherheit der Energieversorgung

    NARCIS (Netherlands)

    Amineh, M.P.

    2006-01-01

    China hat vor kurzem Japan im Bereich des Öl- und Gasverbrauchs überholt und steht damit weltweit an zweiter Stelle. Es ist nur noch eine Frage der Zeit, wann der Ölverbrauch den der Vereinigten Staaten übersteigen wird, da Prognosen davon ausgehen, dass Chinas Bruttoinlandsprodukt (GDP) zwischen 20

  18. Politik und Sprachpolitik in der Lexikographie

    DEFF Research Database (Denmark)

    Bergenholtz, Henning; Tarp, Sven

    2007-01-01

    Lexikographie und Sprachpolitik haben gemeinsam, dass beide Bereiche eine lange Geschichte aufweisen können, und dass sie seit etwa 25 Jahren ein zunehmendes akademisches Interesse gewonnen haben. Die Sprachpolitik hat darüber hinaus in den letzten Jahren ein großes öffentliches Interesse gefunde...

  19. Internet, Kapitalismus und periphere Entwicklung im Waldviertel

    Directory of Open Access Journals (Sweden)

    Christian Fuchs

    2015-03-01

    Full Text Available Das Waldviertel ist eine strukturschwache Region im Norden Österreichs, die eine innere Peripherie und innere Kolonie des österreichischen und europäischen Kapitalismus darstellt. Dieser Artikel analysiert die politische Ökonomie des Internets im Waldviertel. Das Waldviertel ist konfrontiert mit hohen Ausbeutungsraten im Rahmen einer imperialistischen Arbeitsteilung, Werttransfer, ungleichem Tausch, Niedriglöhnen, der Abwanderung der Textilindustrie, hoher Arbeitslosigkeit, Landflucht, dem Abbau öffentlicher Infrastruktur und Bevölkerungsrückgang. Die Analyse verdeutlicht, dass die Situation des Waldviertels als innere Peripherie der kapitalistischen Zentren die Kommunikationsverhältnisse prägt. Der Zugang zu Computern, dem Internet und Breitband ist im Waldviertel schlechter als in anderen Regionen, die Internet- und Mobiltelefonverbindungsgeschwindigkeit ist tendenziell langsamer und die Region ist eher unattraktiv für WissensarbeiterInnen. Es gibt im Waldviertel auch Ansätze einer Alternativökonomie, die den Imperialismus infrage stellen. Im Bereich der Informationsökonomie bestehen Potenziale für die Gründung von sozialistischen Kooperativen im Bereich Hardware, Software und soziale Medien, die die kapitalistische Informationsgesellschaft infrage stellen und für Alternativen kämpfen.

  20. Physik gestern und heute Das Eiskalorimeter

    Science.gov (United States)

    Heering, P.

    2003-07-01

    Kalorimetrische Messungen gehören heute zum experimentellen Standardrepertoire im Bereich der Thermodynamik und der physikalischen Chemie. Das erste Gerät für derartige Messungen entwickelten Ende des 18. Jahrhunderts die französischen Wissenschaftler Antoine Laurent Lavoisier und Pierre Simon de Laplace.

  1. Zur Struktur und Funktion von Synonymen

    Directory of Open Access Journals (Sweden)

    Marina Zorman

    1998-12-01

    Full Text Available Der Artikel behandelt die Synonyme im Licht der funktionell-strukturellen Sprachtheorie Coserius. 1 Die Wahl der theoretischen Grundsätze wurde durch die Festellung diktiert, daß die bisherigen Erkenntnisse über die Synonymie widersprüchlich sind und daß auch schon über alle Feststellungen berechtigte Einsprüche erhoben wurden. Deshalb wird in dieser Arbeit auf der genannten theoretischen Grundlage, die verschiedene Gesichtspunkte des Problems verbindet, anstatt sie zu trennen (s. Punkt 2, ein Modell für die Analyse von Synonymen vorgestellt (3, das die klassischen Schwächen der Semantikforschung (zu geringe Menge tatsächlicher Daten, Subjektivität und Introspektion durch eine empirische Untersuchung in einem Textkorpus zu ersetzen versucht. In die Analyse sind drei Inhaltsebenen einbezogen (Bezeichnung, Bedeutung und Sinn und ihnen sind jeweils entsprechende Untersuchungsmethoden zugeordnet. Im Sinne des Modells wurden in der Arbeit Zorman 1997 zwei slowenische Synonympaare (kuverta - ovojnica und borba - boj analysiert, die als Beispiele reiner (und totaler Synonymie gelten können. Die Analyse wird aus Platzgründen an dieser Stelle nicht detailliert dargestellt,2 veranschaulicht werden nur ihre Tragweite und die Ergebnisse (4. Im letzten Teil (5 werden die Leistungen der vorgeschlagenen Methode bewertet und einige Annahmen dargestellt, die der weiteren Erforschung der Synonyme dienen könnten. Die objektive Behandlung der Synonymie unter unterschiedlichen Gesichtspunkten scheint einige Dogmen über Synonyme in Frage zu  stellen.

  2. Modellbasierte Steuerung, Regelung und Diagnose von Brennstoffzellenantrieben

    Science.gov (United States)

    Bußhardt, Joachim; Baaser, Bernhard; Formanski, Volker; Schäfer, Sascha; Sinsel, Stefan

    Steigende Bevölkerungszahlen und damit zunehmender Energiebedarf stellen eine große Herausforderung für Menschheit und Umwelt dar. Mit steigendem Wohlstand ist auch ein stärkeres Bedürfnis nach Mobilität und damit ein höherer Energieverbrauch verbunden. Die derzeitigen enormen Steigerungen des Bruttoinlandsproduktes in China und Indien - zwei Ländern, die zusammen mehr als ein Drittel der Weltbevölkerung stellen - lassen auch zukünftig ungebrochene Steigerungen des Weltenergieverbrauches erwarten. Dies gilt für alle Bereiche, besonders aber für den Verkehrssektor. Letzterer stellt mit seinem signifikanten Anteil am Energieverbrauch sowie den damit einhergehenden Emissionen und seinem hohen Wachstumspotenzial ein besonderes Handlungsfeld dar. Insbesondere wegen der in diesem Sektor zu erwartenden ansteigenden CO2-Emissionen stehen Effizienzverbesserungen und die Entwicklung alternativer Antriebe im Vordergrund. Dabei spielt die Brennstoffzelle als Fahrzeugantrieb eine entscheidende Rolle, da sie einen hohen Systemwirkungsgrad mit fehlenden CO2- und Schadstoffemissionen verbindet. Wegen der hohen Komplexität sind dabei moderne Steuerungs-, Regelungs- und Diagnoseverfahren von besonderer Bedeutung, auf die in diesem Beitrag näher eingegangen wird. Neben einigen grundlegenden Konzepten wird an Hand zweier Beispiele das Potenzial modellgestützter Methoden aufgezeigt.

  3. Evaluation Of Communal Wastewater Treatment Plant Operating Anaerobic Baffled Reactor And Biofilter

    Directory of Open Access Journals (Sweden)

    Evy Hendriarianti

    2016-02-01

    Full Text Available Construction of communal Waste Water Treatment Plant, WWTP in city of Malang since 1998 but until recently had never done an evaluation the performance. Communal WWTP performance evaluation is needed to see how far the efficiency of processing result. Until now, Environmental Agency Malang City only measure effluent from WWTP Communal  to know the suitability  with domestic wastewater quality standards. Effluent quality data in 2014 showed value above the quality standard of domestic wastewater from East Java Governor Regulation No. 72 in 2013 for parameters BOD and COD. WWTP Communal USRI research objects are on a six (6 locations by involving the user community during the planning, construction, operation and maintenance. Technology choice of ABR followed by a biofilter reactor with the stone media proved capable of processing organic matter of BOD and COD with the removal levels respectively by 78% -99% and 71% -99%. As for the parameters of TSS, NO3 and PO4 have the ranges of removal respectively by 56% -100%, (43% - 72%, (2% - 13%. Ratio BOD and COD in influent are low and ranged from 0.22 to 0.41. From the evaluation shows that high organic matter concentrations in influent along with the HRT and operation time high will result in a higher removal level

  4. Nitrate and COD removal in an upflow biofilter under an aerobic atmosphere.

    Science.gov (United States)

    Ji, Bin; Wang, Hongyu; Yang, Kai

    2014-04-01

    A continuous-upflow submerged biofilter packed with ceramsite was constructed for nitrate removal under an aerobic atmosphere. Pseudomonas stutzeri X31, an aerobic denitrifier isolate, was added to the bioreactor as an inoculum. The influent NO3(-)-N concentrations were 63.0-73.8 mg L(-1). The best results were achieved when dissolved oxygen level was 4.6 mg L(-1) and C/N ratio was 4.5. The maximum removal efficiencies of carbon oxygen demand (COD) and NO3(-)-N were 94.04% and 98.48%, respectively at 30°C, when the hydraulic load was 0.75 m h(-1). The top section of the bioreactor possessed less biofilm but higher COD and NO3(-)-N removal rates than the bottom section. Polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) technique combined with electron microscopic examination indicated P. stutzeri X31 and Paracoccus versutus were the most dominant bacteria. Amoeba sp., Vorticella sp., Philodina sp., and Stephanodiscus sp. were also found in the bioreactor.

  5. Soluble microbial products in pilot-scale drinking water biofilters with acetate as sole carbon source.

    Science.gov (United States)

    Zhang, Ying; Ye, Chengsong; Gong, Song; Wei, Gu; Yu, Xin; Feng, Lin

    2013-04-01

    A comprehensive study on formation and characteristics of soluble microbial products (SMP) during drinking water biofiltration was made in four parallel pilot-scale ceramic biofilters with acetate as the substrate. Excellent treatment performance was achieved while microbial biomass and acetate carbon both declined with the depth of filter. The SMP concentration was determined by calculating the difference between the concentration of dissolved organic carbon (DOC), biodegradable dissolved organic carbon (BDOC) and acetate carbon. The results revealed that SMP showed an obvious increase from 0 to 100 cm depth of the filter. A rising specific ultraviolet absorbance (SUVA) was also found, indicating that benzene or carbonyl might exist in these compounds. SMP produced during this drinking water biological process were proved to have weak mutagenicity and were not precursors of by-products of chlorination disinfection. The volatile parts of SMP were half-quantity analyzed and most of them were dicarboxyl acids, others were hydrocarbons or benzene with 16-17 carbon atoms.

  6. Thermal conductivity of leaf compost used in biofilters: An experimental and theoretical investigation

    Energy Technology Data Exchange (ETDEWEB)

    Chandrakanthi, M. [Centre for Environmental Engineering Research and Education (CEERE), Department of Civil Engineering, University of Calgary, Calgary, Alberta, T2N 1N4 (Canada); Mehrotra, A.K. [Centre for Environmental Engineering Research and Education (CEERE), Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta, T2N 1N4 (Canada); Hettiaratchi, J.P.A. [Centre for Environmental Engineering Research and Education (CEERE), Department of Civil Engineering, University of Calgary, Calgary, Alberta, T2N 1N4 (Canada)]. E-mail: jhettiar@ucalgary.ca

    2005-07-15

    Thermal conductivity is an important property that governs the behaviour of leaf compost biofilters used in treating gaseous pollutants. Measurements were carried out for the thermal conductivity (K) of 44 samples of leaf compost, covering wide ranges of the volume fractions of water ({xi}{sub w}), solids ({xi}{sub s}) and air ({xi}{sub a}), at 20 deg. C using an unsteady state thermal probe. The results indicated that the compost thermal conductivity increased with an increase in {xi}{sub w}, with a decrease in {xi}{sub a}, and with an increase in the degree of saturation (defined as the volumetric fraction of water in the total void space). The predictions from the Woodside-Messmer quadratic parallel (QP) model for the thermal conductivity of leaf compost were higher than the experimental values. A simple linear relationship was developed between the thermal conductivity and the degree of saturation, which provided a satisfactory correlation for the data measured in this study as well as those reported recently for sandy and clay loams. -Thermal conductivity of compost exhibits a linear relationship with the degree of saturation of the matrix.

  7. Aquamicrobium ahrensii sp. nov. and Aquamicrobium segne sp. nov., isolated from experimental biofilters.

    Science.gov (United States)

    Lipski, André; Kämpfer, Peter

    2012-10-01

    Two groups of Gram-negative, aerobic bacterial strains previously isolated from experimental biofilters were investigated to determine their taxonomic position. Based on their 16S rRNA gene sequences, these isolates formed two distinct groups within the genus Aquamicrobium. The gene sequence similarities of the new isolates to the type strains of Aquamicrobium species were below 98.3 %. The presence of ubiquinone-10, C(18 : 1) cis 11 as the predominant fatty acid and a polar lipid pattern with phosphatidylglycerol, phosphatidylcholine, diphosphatidylglycerol and phosphatidylethanolamine was in accordance with the characteristics of this genus. The results of DNA-DNA hybridization, biochemical tests and chemotaxonomic properties allowed genotypic and phenotypic differentiation of the strains from all recognized species of the genus Aquamicrobium. Therefore, the isolates were assigned to two novel species of this genus for which the names Aquamicrobium ahrensii sp. nov. (type strain 905/1(T) = DSM 19730(T) = CCUG 55251(T)) and Aquamicrobium segne sp. nov. (type strain 1006/1(T) = DSM 19714(T) = CCUG 55250(T)) are proposed. An emended description of the genus Aquamicrobium is also presented.

  8. Evaluation of aerated biofilter systems for microbial methane oxidation of poor landfill gas.

    Science.gov (United States)

    Haubrichs, R; Widmann, R

    2006-01-01

    In the long-term, landfills are producing landfill gas (LFG) with low calorific values. Therefore, the utilization of LFG in combined heat and power plants (CHP) is limited to a certain period of time. A feasible method for LFG treatment is microbial CH(4) oxidation. Different materials were tested in actively aerated lab-scale bio-filter systems with a volume of 0.167 m(3). The required oxygen for the microbial CH(4) oxidation was provided through perforated probes, which distributed ambient air into the filter material. Three air input levels were installed along the height of the filter, each of them adjusted to a particular flow rate. During the tests, stable degradation rates of around 28 g/(m(3) h) in a fine-grained compost material were observed at a CH(4) inlet concentration of 30% over a period of 148 days. Compared with passive (not aerated) tests, the CH(4) oxidation rate increased by a factor of 5.5. Therefore, the enhancement of active aeration on the microbial CH(4) oxidation was confirmed. At a O(2)/CH(4) ratio of 2.5, nearly 100% of the CH(4) load was decomposed. By lowering the ratio from 2.5 to 2, the efficiency fell to values from 88% to 92%. By varying the distribution to the three air input levels, the CH(4) oxidation process was spread more evenly over the filter volume.

  9. Submerged aerated bio-filter (SAB)--a post treatment option for UASB effluent treating sewage.

    Science.gov (United States)

    Sudhir, Padigala; Gaur, Rubia Zahid; Khan, Abid Ali; Kazmi, A A; Mehrotra, Indu

    2013-07-01

    This paper presents exploratory results of the performance of submerged aerated bio-filter (SAB-1.5 L) for the post treatment of UASB effluent treating sewage in order to bring the effluent quality in compliance with discharge standards. The study was carried out in three stages with varied dissolved oxygen (DO) levels of 0 to 2.0, 2.0 to 4.0, 4.0 to 6.0 and > 6.0 mg/L. The hydraulic retention time (HRT) and hydraulic loading rate (HLR) were maintained 0.67 h & 0.1 m3/ m2 x h respectively in all stage of study. The performance in terms of BOD removal efficiency was increased with increase in DO levels. Results revealed that the average BOD and SS removal efficiencies in phases 3 and 4 were 51.3 and 59.5% and 58.8 and 67.5% respectively. Significant ammonical nitrogen (NH4-N) removal of 60% was observed in phase 4. The BOD and SS in phases 3 and 4 were reduced to well below the effluent disposal standards. The SAB at DO ≥ 4 mg/L can be considered a viable alternative for the post treatment of effluent from UASB treating domestic wastewater.

  10. [Removal pathway and influence factors of hydroponic bio-filter method for nitrogen and phosphorus].

    Science.gov (United States)

    Li, Xian-ning; Song, Hai-liang; Lü, Xi-wu; Osamu, Nishimura; Yuhei, Inamori

    2007-05-01

    Study was made on the use of hydroponic bio-filter method (HBFM) for eutrophic surface water. Results show that HBFM can remove 16.8% of TN and 30.8% of TP at the hydraulic loading rate (HLR) of 3.0 m3/(m2 x d). The removal loading rate of TN and TP can accordingly reach 1.0 and 0.1 g/(m2 x d) respectively. The sedimentation of particulate nitrogen and particulate phosphorus plays a major role in nitrogen and phosphorus removal, and its contribution is 62.2% and 75.9% respectively. The optimal HLR of HBFM ranges from 3.0 to 4.0 m3/(m x d). The intension of secateur for Nasturtium officinale has some effect on its uptake rate, thus the length of cut when harvesting should be less than 10 cm. The harvesting frequency of once a month for Nasturtium officinale has no effect on nitrogen and phosphorus removal of HBFM.

  11. Performance evaluation of biofilters and biotrickling filters in odor control of n-butyric acid.

    Science.gov (United States)

    Ding, Ying; Han, Zhiying; Wu, Weixiang; Shi, Dezhi; Chen, Yingxu; Li, Wenhong

    2011-01-01

    With the rapid development of swine production in China, odor pollution associated with piggery facilities has become an increasing environmental concern. N-butyric acid (n-BA) is one of the key odor compounds selected to represent volatile fatty acids (VFAs) found in piggery facilities. In this study, two biofilters (BFs) packed with compost (BFC) or sludge (BFS) and two biotrickling filters (BTFs) packed with pall rings (BTFP) or multidimensional hollow balls (BTFM), respectively, were compared with regard to their performances in the removal of n-BA. The non-biological removal capacities of packing material of the bioreactors on a per unit volume basis were BFS>BFC>BTFM>BTFP. Maximum biological removal capacities per unit volume of packing material of the bioreactors all exceeded 9.1 kg/m(3)·d and in the order of BFC>BTFM>BFS>BTFP. Kinetic analysis as well as overall evaluation by radar graphs showed that the BTFs achieved superior removal rates to the BFs in the order of BTFM>BTFP>BFC>BFS. The biotrickling filter packed with multidimensional hollow balls could be an effective technology for VFAs removal. Results from this research provide economical and effective alternatives for odor control in piggery facilities.

  12. Utilization of toxic and vapors as alternate electron acceptors in biofilters

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B.D.; Apel, W.A.; Walton, M.R.

    1997-08-01

    Conceptually, biofilters are vapor phase bioreactors that rely on microorganisms in the bed medium to oxidize contaminants in off-gases flowing through the bed to less hazardous compounds. In the most studied and utilized systems reduced compounds such as fuel hydrocarbons are enzymatically oxidized to compounds such as carbon dioxide and water. In these types of reactions the microorganisms in the bed oxidize the contaminant and transfer the electrons to oxygen which is the terminal electron acceptor in the process. In essence the contaminant is the carbon and energy source for the microorganisms in the bed medium and through this catabolic process oxygen is reduced to water. An example of this oxidation process can be seen during the degradation of benzene and similar aromatic compounds. Aromatics are initially attacked by a dioxygenase enzyme which oxidizes the compounds to a labile dihydrodiole which is spontaneously converted to a catechol. The dihydroxylated aromatic rings is then opened by oxidative {open_quotes}ortho{close_quotes} or {open_quotes}meta{close_quotes} cleavage yielding cis, cis-muconic acid or 2-hydroxy-cis, cis-muconic semialdehyde, respectively. These organic compounds are further oxidized to carbon dioxide or are assimilated for cellular material. This paper describes the conversion of carbon tetrachloride using methanol as the primary carbon and energy source.

  13. Selection of commercial biofilters for rearing aquatic animals in closed system

    Directory of Open Access Journals (Sweden)

    Chuayrodmod, J.

    2007-07-01

    Full Text Available A comparative study was made to select the most suitable biofilter from 7 types of commercial water filters by rearing hybrid catfish (Clarias macrocephalus x C. gariepinus in aquaria for 64 days. It was found that diminishing concentrations of ammonia and nitrite were attributed mainly to nitrifying bacteria that convert ammonia into nitrite and nitrate which required a minimum period of 16-28 days for the process to function. Low absorption of ammonia was achieved through using activated carbon, coconut shell charcoal, zeolite and ceramic. Durability and filtering efficiency of the filters depended upon porosity and amount of biofilm on the filter surface. The filter using one coarse meshed plastic sheet and 37 bioballs was the most suitable, though it caused a problem with low total alkalinity resulting in mortality of the biofilm which peeled off, thus increasing the concentrations of ammonia, nitrite and suspended solids toward the end of the experimental period. The catfish growth rate, survival and FCR in all treatments were in the ranges of 7.39-8.91 g/d, 84.44-95.56% and 0.21-0.25, respectively.

  14. Enhanced phosphorus recovery and biofilm microbial community changes in an alternating anaerobic/aerobic biofilter.

    Science.gov (United States)

    Tian, Qing; Ong, Say Kee; Xie, Xuehui; Li, Fang; Zhu, Yanbin; Wang, Feng Rui; Yang, Bo

    2016-02-01

    The operation of an alternating anaerobic/aerobic biofilter (AABF), treating synthetic wastewater, was modified to enhance recovery of phosphorus (P). The AABF was periodically fed with an additional carbon source during the anaerobic phase to force the release of biofilm-sequestered P which was then harvested and recovered. A maximum of 48% of the total influent P was found to be released in the solution for recovery. Upon implementation of periodic P bio-sequestering and P harvesting, the predominant bacterial communities changed from β-Proteobacteria to γ-Proteobacteria groups. The genus Pseudomonas of γ-Proteobacteria was found to enrich greatly with 98% dominance. Dense intracellular poly-P granules were found within the cells of the biofilm, confirming the presence of P accumulating organisms (PAOs). Periodic addition of a carbon source to the AABF coupled with intracellular P reduction during the anaerobic phase most probably exerted environmental stress in the selection of Pseudomonas PAOs over PAOs of other phylogenic types. Results of the study provided operational information on the selection of certain microbial communities for P removal and recovery. This information can be used to further advance P recovery in biofilm systems such as the AABFs.

  15. Mesquite wood chips (Prosopis) as filter media in a biofilter system for municipal wastewater treatment.

    Science.gov (United States)

    Sosa-Hernández, D B; Vigueras-Cortés, J M; Garzón-Zúñiga, M A

    2016-01-01

    The biofiltration system over organic bed (BFOB) uses organic filter material (OFM) to treat municipal wastewater (MWW). This study evaluated the performance of a BFOB system employing mesquite wood chips (Prosopis) as OFM. It also evaluated the effect of hydraulic loading rates (HLRs) in order to achieve the operational parameters required to remove organic matter, suspended material, and pathogens, thus meeting Mexican and US regulations for reuse in irrigation. Two biofilters (BFs) connected in series were installed; the first one aerated (0.62 m(3)air m(-2)h(-1)) and the second one unaerated. The source of MWW was a treatment plant located in Durango, Mexico. For 200 days, three HLRs (0.54, 1.07, and 1.34 m(3)m(-2)d(-1)) were tested. The maximum HLR at which the system showed a high removal efficiency of pollutants and met regulatory standards for reuse in irrigation was 1.07 m(3)m(-2)d(-1), achieving removal efficiencies of biochemical oxygen demand (BOD5) 92%, chemical oxygen demand (COD) 78%, total suspended solids (TSS) 95%, and four log units of fecal coliforms. Electrical conductivity in the effluent ensures that it would not cause soil salinity. Therefore, mesquite wood chips can be considered an innovative material suitable as OFM for BFs treating wastewaters.

  16. Freshwater Recirculating Aquaculture System Operations Drive Biofilter Bacterial Community Shifts around a Stable Nitrifying Consortium of Ammonia-Oxidizing Archaea and Comammox Nitrospira

    Science.gov (United States)

    Bartelme, Ryan P.; McLellan, Sandra L.; Newton, Ryan J.

    2017-01-01

    Recirculating aquaculture systems (RAS) are unique engineered ecosystems that minimize environmental perturbation by reducing nutrient pollution discharge. RAS typically employ a biofilter to control ammonia levels produced as a byproduct of fish protein catabolism. Nitrosomonas (ammonia-oxidizing), Nitrospira, and Nitrobacter (nitrite-oxidizing) species are thought to be the primary nitrifiers present in RAS biofilters. We explored this assertion by characterizing the biofilter bacterial and archaeal community of a commercial scale freshwater RAS that has been in operation for >15 years. We found the biofilter community harbored a diverse array of bacterial taxa (>1000 genus-level taxon assignments) dominated by Chitinophagaceae (~12%) and Acidobacteria (~9%). The bacterial community exhibited significant composition shifts with changes in biofilter depth and in conjunction with operational changes across a fish rearing cycle. Archaea also were abundant, and were comprised solely of a low diversity assemblage of Thaumarchaeota (>95%), thought to be ammonia-oxidizing archaea (AOA) from the presence of AOA ammonia monooxygenase genes. Nitrosomonas were present at all depths and time points. However, their abundance was >3 orders of magnitude less than AOA and exhibited significant depth-time variability not observed for AOA. Phylogenetic analysis of the nitrite oxidoreductase beta subunit (nxrB) gene indicated two distinct Nitrospira populations were present, while Nitrobacter were not detected. Subsequent identification of Nitrospira ammonia monooxygenase alpha subunit genes in conjunction with the phylogenetic placement and quantification of the nxrB genotypes suggests complete ammonia-oxidizing (comammox) and nitrite-oxidizing Nitrospira populations co-exist with relatively equivalent and stable abundances in this system. It appears RAS biofilters harbor complex microbial communities whose composition can be affected directly by typical system operations while

  17. CDF modeling of flow and transport processes in the reactor core of a modular high temperature reactor during an air ingress accident; CFD-Modellierung der Stroemungs- und Transportprozesse im Reaktorkern eines modularen Hochtemperaturreaktors waehrend eines Lufteinbruchstoerfalls

    Energy Technology Data Exchange (ETDEWEB)

    Baggemann, Johannes

    2015-05-22

    Generation IV of reactor design is supposed to include inherent safety systems that allow accident management using passive processes (without external energy). The VTR (very high temperature reactor) is graphite moderated with helium cooling. The design concept assumes that in any operational situation the after heat is removed by thermal conduction and radiation. Air ingress is beyond-design accident assuming a leak in the primary circuit triggering oxygen reaction with the hot graphite that could damage the barriers for fission product release. Using 3D CFD (computational fluid dynamics) codes the air ingress scenario is simulated, the flow and transport processes in the reactor core are analyzed. For validation of the modeling heat transport processes were investigated in specific test facilities.

  18. Modeling of radionuclide transport through rock formations and the resulting radiation exposure of reference persons. Calculations using Asse II parameters; Modellierung des Transports von Radionukliden durch Gesteinsschichten und der resultierenden Strahlenexposition von Referenzpersonen. Berechnungen mit Parametern der Asse II

    Energy Technology Data Exchange (ETDEWEB)

    Kueppers, Christian; Ustohalova, Veronika; Steinhoff, Mathias

    2012-05-21

    The long-term release of radioactivity into the ground water path cannot be excluded for the radioactive waste repository Asse II. The possible radiological consequences were analyzed using a radio-ecological scenario developed by GRS. A second scenario was developed considering the solubility of radionuclides in salt saturated solutions and retarding/retention effects during the radionuclide transport through the cap rock layers. The modeling of possible radiation exposure was based on the lifestyle habits of reference persons. In Germany the calculation procedure for the prediction of radionuclide release from final repositories is not defined by national standards, the used procedures are based on analogue methods from other radiation protection calculations.

  19. Mathematical modelling of dust samplers and application of the method to the gravimetric dust sampler RESPICON; Mathematische Modellierung von Staubmessgeraeten und Anwendung der Methode auf das gravimetrische Staubmessgeraet RESPICON

    Energy Technology Data Exchange (ETDEWEB)

    Armbruster, L. [Deutsche Montan Technologie GmbH, Essen (Germany). Gas and Fire Div.

    2004-07-01

    The evaluation and assessment of the fractionating particle sampler RESPICON due to the European test standard prEN 13205 has been continued by mathematical modelling of the candidate sampler and its response to different aerosols, characterized by the mean aerodynamic particle size (MMAD) and standard deviation (GSD). The three health related size fractions are sampled by the candidate sampler within the limits given by the standard, but correction factors for each fraction have to be taken into account. This result stands only for the use of the candidate as affixed point sampler. But due to the regulations in the standard it can be used as a personal sampler for windspeeds up to 2/ms. The investigations also have shown some disadvantages of the test standard itself, these should be eliminated in the future. (orig.)

  20. Synthese und Charakterisierung von binären und ternären Verbindungen im System Metall-Silicium-Kohlenstoff

    OpenAIRE

    Karyasa, I Wayan

    2004-01-01

    Im Mittelpunkt der vorliegenden Arbeit stehen Darstellung und Charakterisierung von neuartigen keramischen Verbindungen im System Metall-Silicium-Kohlenstoff (Metall = Co,Cr, Al, Ca, Mg und Ba). Die Darstellung erfolgte bei hohen Temperaturen aus den Edukten Metall, Silicium und Kohlenstoff (bzw. Siliciumcarbid) unter reduzierenden Bedingungen (Hochtemperatursynthese). Die Reaktionsprodukte wurden mittels Röntgenbeugung und Elektronenmikroskopie charakterisiert. Bei der Charakterisierung lag ...