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Sample records for durch partielle oxidation

  1. Increase of the efficiency of heat pumps by partial defrosting of evaporator during the heating operation; Effizienzsteigerung von Waermepumpen durch partielle Verdampferabtauung waehrend des Heizbetriebs

    Energy Technology Data Exchange (ETDEWEB)

    Mader, Gunda; Thybo, Claus [Danfoss A/S, Nordborg (Denmark)

    2011-07-01

    eine regelmaessige Abtauung des Verdampfers vorgenommen werden. Eine weitverbreitete Methode dazu ist die Umkehrung des Kaeltemittelstroms, bei der heisses Gas aus dem Verdichter in den Verdampfer eingeleitet wird. Neben deutlichen Effizienzverlusten entstehen dabei Probleme der Materialbelastung und bei manchen Anlagentypen Komforteinbussen. Die Methode der partiellen Abtauung zielt darauf ab, die Haeufigkeit der Kreislaufumkehr zu reduzieren oder ganz zu vermeiden. Das Prinzip beruht darauf, einzelne Straenge des Verdampfers abwechselnd zu deaktivieren um dort eine energiesparende Abtauung durch die ueberstroemende Luft zu ermoeglichen. In den uebrigen Bereichen des Verdampfers wird weiterhin Waerme von der Aussenluft auf das Kaeltemittel uebertragen, so dass der Betrieb der Anlage kontinuierlich aufrecht erhalten werden kann. Ermoeglicht wird dies durch ein spezielles Ventil, welches Expansion und Verteilung kombiniert und damit erlaubt, die Kaeltemittelmassenstroeme in den einzelnen Verdampferstraengen gezielt einzustellen. Anhand eines mathematischen Modells werden Details der Methode vorgestellt und diskutiert. Durch experimentelle Untersuchungen an Luft-Luft-Waermepumpen wird gezeigt, dass unter Standard-Betriebsbedingungen mit Lufttemperaturen ueber dem Gefrierpunkt waehrend der Deaktivierungsphase der gesamte Reif abgetaut werden kann und somit keine Kreislaufumkehr erforderlich ist.

  2. Partielle endokrine Veränderungen des alternden Mannes (PEVAM: Facts and Fiction

    Directory of Open Access Journals (Sweden)

    Ponholzer A

    2000-01-01

    Full Text Available Die kontinuierliche Abnahme der Sexualhormone Testosteron und Dehydroepiandrosteronsulfat (DHEA-S in Verbindung mit dem Altern des Mannes steht heutzutage außer Zweifel [1, 2]. Die beim Mann zu beobachtenden Änderungen im Hormonhaushalt unterscheiden sich von denen der Frau durch den langsamen, stetigen Verlauf und die oftmalige Erhaltung der Fertilität bis ins höchste Alter. Es ist daher falsch, von einem "Klimakterium virile" oder von "Andropause" zu sprechen. Das Ausmaß der Abnahme der Androgenspiegel unterliegt, ebenso wie das Bestehen einer assoziierten Symptomatik, einer hohen interindividuellen Streuung. Unter dem Begriff PADAM (partielles Androgendefizit des alternden Mannes werden als Auswirkung verminderter Androgenspiegel vielfältige Symptome beschrieben, wie zum Beispiel Hitzewallungen, Schlafstörungen, Einschränkungen des Wohlbefindens und der Sexualität sowie Abnahme von Knochendichte und Muskelmasse oder Veränderung von Fettverteilungsmuster und Gesamtkörperfettanteil. Bei Vorliegen von einem oder mehreren der oben genannten Symptome in Verbindung mit entsprechend verminderten Testosteronspiegeln existiert die Möglichkeit einer Substitutionstherapie, sowohl zur Prävention, als auch zur Therapie negativer Auswirkungen des Mangels. Potentielle Risiken einer Androgentherapie scheinen kontrollierbar, werden aber erst in Zukunft durch umfassende Langzeitstudien in ihrem ganzen Ausmaß beurteilbar sein. Andere Hormonsysteme, wie etwa Wachstumshormone (GH oder Melatonin unterliegen ebenfalls einer altersassozierten Abnahme. Auch hier darf eine Auswirkung auf die Lebensqualität angenommen werden, die Sinnhaftigkeit einer Ersatztherapie ist bei GH und Melatonin, wie auch bei DHEA-S, jedoch umstritten.

  3. Effizienzsteigerung durch intelligente Planung

    Science.gov (United States)

    Maier, Walther; Bader, Alexander

    Das Umfeld der produzierenden Unternehmen hat sich in den letzten Jahren sehr gewandelt. Dieser Wandel ist geprägt durch die Folgen der Globalisierung und deren Folgeerscheinungen. Produzierende Unternehmen versuchen auf diese geänderten Rahmenbedingungen durch Steigerung ihrer Produktivität und Flexibilität zu reagieren.

  4. Reducing available amounts of heavy metals in contaminated soils by adding iron oxides. Final report; Verringerung der Bioverfuegbarkeit von Schwermetallen in kontaminierten Boeden durch Zugabe von Eisenoxiden. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Pluquet, E; Mueller, I

    1998-02-01

    This project was part of a German-French research co-operation and investigated the practicability to immobilize heavy metals by adding iron oxides to contaminated soils (harbour sediment, bracky marsh contaminated by emission of a zinc/lead smelter, alluvial Gley soil contaminated by mining activity). Pot and field trials were carried out using three different soils. Five iron bearing materials were added to the soil (1% pure Fe in soil dry matter): Red mud from Al-industry, Fe-precipitation sludge from drinking water treatment, bog iron ore, unused steel shot and steel shot waste from surface treatment of rolled steel plates. When mixed with the soil NH{sub 4}NO{sub 3} and DTPA extractable amounts of heavy metals and uptake by plants was markedly reduced. It was demonstrated that precipitated Fe-bearing sludge from drinking water treatment was a very effective material reducing the NH{sub 4}NO{sub 3} soluble amounts by 40-50% (DTPA 30-40%) in the pot tests while the uptake by plants was reduced by 40% and more. Heavy metals were strongly bound in a fixed order Cd>Pb>Zn>Cu and stayed immobilized until the end of project. Heavy metals were immobilized to a certain extent in field trials, but less effect was observed on concentration in plants and soil extracts compared with the pot tests. In practice the treatment should exceed the 1% pure Fe tested and the application should more homogeneously affect the soil layer where the plant roots mainly grow. (orig.) [Deutsch] Im Rahmen eines deutsch-franzoesischen Projektverbundes wurde die Moeglichkeit der Immobilisierung von Schwermetallen in kontaminierten Boeden durch gezielte Zufuhr von Eisenoxiden untersucht. Die praxisorientierten Untersuchungen wurden in Gefaess- und Feldversuchen mit drei unterschiedlichen Boeden (Spuelfeldboden aus Hafenschlick, immissionsbelastete Brackmarsch, durch Bergbau belasteter Auenboden) ausgefuehrt. Dazu wurden fuenf eisen(oxid)haltige Materialien (Rotschlamm aus der Al

  5. Biological degradation of partially oxidated constituents of stabilized sapropel; Biologischer Abbau teiloxidierter Inhaltsstoffe stabilisierter Faulschlaemme

    Energy Technology Data Exchange (ETDEWEB)

    Scheminski, A.; Krull, R.; Hempel, D.C. [Technische Univ. Braunschweig (Germany). Inst. fuer Bioverfahrenstechnik

    1999-07-01

    Partial oxidation of sapropel with ozone destroys the cell walls of microorganisms in sludge and releases the cell constituents. Substances that are not biologically degraded because of the size or structure of their molecules are transformed into smaller, water-soluble and biologically degradable fractions by the reaction with ozone. The experiments aim to render the partially oxidated sewage sludge constituents highly biologically degradable using a minimum of oxidation agents. For the experiments described, stabilized sapropels with low biological activity are used. Hence the ozone is mainly used for the partial oxidation of recalcitrant constituents. (orig.) [German] Durch partielle Oxidation von Faulschlaemmen mit Ozon werden die Zellwaende der Mikroorganismen im Schlamm zerstoert und die Zellinhaltsstoffe freigesetzt. Dabei werden Substanzen, die aufgrund ihrer Molekuelgroesse oder -struktur biologisch nicht abgebaut werden, durch die Reaktion mit Ozon in kleinere, wasserloesliche und biologisch abbaubare Bruchstuecke ueberfuehrt. Ziel der Versuche ist es, durch den Einsatz moeglichst geringer Mengen an Oxidationsmitteln eine hohe biologische Abbaubarkeit der teiloxidierten Klaerschlamminhaltsstoffe zu erreichen. Fuer die hier vorgestellten Experimente wurden stabilisierte Faulschlaemme mit geringer biologischer Aktivitaet eingesetzt. Dadurch wird das Ozon vorwiegend zur Teiloxidation recalcitranter Inhaltsstoffe genutzt. (orig.)

  6. Bubble-free ozone addition through ceramic membranes for wet-oxidative waste water treatment; Blasenfreier Ozoneintrag durch keramische Membranen zur nassoxidativen Abwasserbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Janknecht, P.; Wilderer, P.A. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl und Pruefamt fuer Wasserguete- und Abfallwirtschaft

    1999-07-01

    A prerequisite for successful wet oxidation is very accurately tuned and carefully monitored process control. In the alternative, a decline in water quality is actually possible. In particular, earlier studies in the ozonification of landfill leachate encountered problems in reducing levels of AOX in the presence of halogenated hydrocarbons. Serious problems in process control may arise when ozone is conventionally added and forms bubbles in the presence of surface-active substances; this foam accumulates and is so persistent as to evade mechanical control. Since the formation of foam is directly due to gas bubbles carried in, bubble-free addition of ozone through a membrane may be a viable approach. (orig.) [German] Voraussetzung fuer den Erfolg einer Nassoxidation ist eine sehr genau eingestellte und sorgfaeltig ueberwachte Prozessfuehrung, da anderenfalls auch eine Verschlechterung der Wasserqualitaet eintreten kann; insbesondere haben sich hier bei frueheren Untersuchungen zur Ozonung von Deponiesickerwaessern Schwierigkeiten bei der Reduzierung des AOX-Wertes in Anwesenheit von halogenierten Kohlenwasserstoffen ergeben. Gravierende Schwierigkeiten in der Prozessfuehrung kann Schaum bereiten, der sich bei konventionellem Blaseneintrag des Ozons in Anwesenheit von oberflaechenaktiven Substanzen bildet, sich in der Anlage ansammelt und dabei so bestaendig ist, dass er auf mechanische Weise nicht zu kontrollieren ist. Da die Schaumbildung direkt auf die eingetragenen Gasblasen zurueckzufuehren ist, stellt der blasenfreie Eintrag von Ozon durch eine Membran einen moeglichen Loesungsansatz dar. (orig.)

  7. prise en charge des complications de la chirurgie partielle du larynx

    African Journals Online (AJOL)

    ... type de la chirurgie partielle pratiquée et du type d'antibiothérapie utilisée. ... S. Touati, S. Gritli. Service d'ORL et de chirurgie cervico-faciale Institut Salah Azaiez .... tée par corticothérapie et une photo coagulation au laser. CO2. Aussi, un ...

  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. 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

  10. Synthesis gas generation by high pressure partial oxidation (HP POX {sup registered}); Synthesegaserzeugung durch Hochdruck-Partialoxidation (HP POX {sup registered})

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, B.; Seifert, P.; Zeissler, R. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Energieverfahrenstechnik und Chemieingenieurwesen; Walter, St. [Lurgi AG, Frankfurt/Main (Germany)

    2005-05-01

    The high pressure synthesis gas process HP POX (High Pressure Partial Oxidation) is a thermal conversion process, which converts e.g. natural gas or heavy residue oil with oxygen to fuel or synthesis gas. Innovative burner technologies allow autothermal catalytic or non-catalytic reforming of gaseous feedstock and gasification of liquid feed streams. Hydrogen and carbon monoxide rich synthesis gases with low methane content (particularly suitable as feed gas for methanol synthesis) can be generated. The technology represents a new generation of entrained flow gasification characterized by the new developed equipment and a design pressure of 100 bar. According to the feeds, the HP POX gasification process is the link between the downstream synthesis chemistry (use of gaseous and liquid feeds) and the power plant process (liquid or solid fuels as suspension or slurry). The HP POX development is carried out together with the Lurgi AG at the Institute for Energy Process Engineering and Chemical Engineering (IEC). The 5 MW HP POX test plant built in Freiberg by Lurgi is core of the joint research project, which is supported by the German Federal Ministry of Economics and Labour (BMWA), the Saxon Ministry of Science and the Fine Arts (SMWK), and the mg technologies ag (parent company of Lurgi). The conducted sets of experiments indicate that the unit can be operated in a safe, smooth and stable manner. During this periods of operation, which included nine test campaigns for autothermal reforming (ATR), the maximum pressure for ATR amounted to 70 bar which exceeds the current benchmark in industry for 30 bar. Main objective of R and D work is the development of modelling tools for extreme gasification conditions and different gasification principles of up to 100 bar. These tools are supposed to improve the understanding of the entire gasification process. Their development requires a systematic investigation of the reaction mechanisms and the interactions with the process

  11. Effet de la substitution partielle de la farine de blé par la purée de ...

    African Journals Online (AJOL)

    La production de la pulpe séchée peut se faire à moindre coût. Mots clés : Substitution partielle, Farine de blé, Pulpe séchée, Purée de banane plantain Musa AAB, Gâteaux de plantain. Effect of partial substitution of wheat flour with mashed ripe plantain (Musa AAB) on pastry products quality. Objective: Plantain, third food ...

  12. Effet de la substitution partielle de la farine de blé par la purée de ...

    African Journals Online (AJOL)

    SARAH

    31 oct. 2014 ... de plantain bien mûr pourrait être recommandée aux industries locales dans la fabrication des produits de pâtisserie de haute qualité. La production de la pulpe séchée peut se faire à moindre coût. Mots clés : Substitution partielle, Farine de blé, Pulpe séchée, Purée de banane plantain Musa AAB,.

  13. Partial radiative capture of resonance neutrons; Capture radiative partielle des neutrons de resonance

    Energy Technology Data Exchange (ETDEWEB)

    Samour, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The radiative capture of resonance neutrons has been studied near the Saclay linac between 0.5 and 700 eV with time-of-flight method and a Ge(Li) detector. {sup 195}Pt + n and {sup 183}W + n allow the study of the distribution of partial radiative widths and their eventual correlation and also the variation of < {gamma}{sub {gamma}{sub i}} > with E{sub {gamma}}. The mean values of Ml and El transition intensities are compared in several tin isotopes. Interference effects, either between resonances or between direct capture and resonant capture are found in {sup 195}Pt + n, {sup 197}Au + n and {sup 59}Co + n. The excited level schemes of a great deal of nuclei are obtained and compared with theoretical predictions. This study has been completed by an analysis of thermal spectrum. (author) [French] La capture radiative des neutrons de resonance a ete etudiee pres de l'accelerateur lineaire de Saclay entre 0,5 et 700 eV a l'aide de la methode du temps-de-vol et d'un detecteur Ge(Li). Les noyaux {sup 195}Pt + n et {sup 183}W + n permettent l'analyse de la distribution de resonance en resonance des largeurs radiatives partielles {gamma}{sub {gamma}{sub i}} et de leur eventuelle correlation, ainsi que l'etude de la variation de < {gamma}{sub {gamma}{sub i}} > en fonction de E{sub {gamma}}. Les intensites moyennes des transitions Ml et El sont comparees pour quelques isotopes de l'etain. Des effets d'interference, soit entre resonances, soit entre capture directe et capture resonnante sont mis en evidence dans {sup 195}Pt + n, {sup 197}Au + n et {sup 59}Co + n. Enfin les schemas des etats excites d'un grand nombre de noyaux sont obtenus et compares avec les predictions theoriques. Cette etude a ete completee par une analyse des spectres thermiques. (auteur)

  14. Partial radiative capture of resonance neutrons; Capture radiative partielle des neutrons de resonance

    Energy Technology Data Exchange (ETDEWEB)

    Samour, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The radiative capture of resonance neutrons has been studied near the Saclay linac between 0.5 and 700 eV with time-of-flight method and a Ge(Li) detector. {sup 195}Pt + n and {sup 183}W + n allow the study of the distribution of partial radiative widths and their eventual correlation and also the variation of < {gamma}{sub {gamma}{sub i}} > with E{sub {gamma}}. The mean values of Ml and El transition intensities are compared in several tin isotopes. Interference effects, either between resonances or between direct capture and resonant capture are found in {sup 195}Pt + n, {sup 197}Au + n and {sup 59}Co + n. The excited level schemes of a great deal of nuclei are obtained and compared with theoretical predictions. This study has been completed by an analysis of thermal spectrum. (author) [French] La capture radiative des neutrons de resonance a ete etudiee pres de l'accelerateur lineaire de Saclay entre 0,5 et 700 eV a l'aide de la methode du temps-de-vol et d'un detecteur Ge(Li). Les noyaux {sup 195}Pt + n et {sup 183}W + n permettent l'analyse de la distribution de resonance en resonance des largeurs radiatives partielles {gamma}{sub {gamma}{sub i}} et de leur eventuelle correlation, ainsi que l'etude de la variation de < {gamma}{sub {gamma}{sub i}} > en fonction de E{sub {gamma}}. Les intensites moyennes des transitions Ml et El sont comparees pour quelques isotopes de l'etain. Des effets d'interference, soit entre resonances, soit entre capture directe et capture resonnante sont mis en evidence dans {sup 195}Pt + n, {sup 197}Au + n et {sup 59}Co + n. Enfin les schemas des etats excites d'un grand nombre de noyaux sont obtenus et compares avec les predictions theoriques. Cette etude a ete completee par une analyse des spectres thermiques. (auteur)

  15. Investigation of partial oxidation of hydrogen sulfide for dry desulfurisation of fuel gases; Untersuchung der Partialoxidation von Schwefelwasserstoff zur Trockenentschwefelung von Brenngasen

    Energy Technology Data Exchange (ETDEWEB)

    Kliemczak, U.

    2002-07-01

    Three process variants for direct desulfurisation in the dry state of coal gasification gases by partial oxidation of H{sub 2}S were investigated in Prenflo conditions: 1. Heterogeneously catalyzed partial oxidation of H{sub 2}S on fly dust followed by sulfur deposition on the dust; 2. Non-catalyzed partial oxidation of H{sub 2}S in a homogeneous gaseous phase followed by sulfur deposition in a spray separator; 3. Heterogeneously catalyzed partial oxidation of H{sub 2}S in a fixed bed. The experiments were carried out in conditions similar to the crude gas conditions of slag bath gasification at SVZ Schwarze Pumpe. The fixed bed materials investigated were hearth furnace coke, Berl saddles, and an activated carbon developed specially for the investigations, Oxorbon CJ. The focus of the investigations was on the envisaged continuous operation of the process. [German] Im Rahmen der vorliegenden Arbeit wurde an einer zu diesem Zweck modifizierten Technikumsanlage die trockene Direktentschwefelung von Brenngasen aus der Kohlevergasung durch partielle Oxidation von H{sub 2}S untersucht. Im Vordergrund standen zwei Verfahrensvarianten, deren Eignung fuer die Bedingungen der Prenflo-Vergasung ueberprueft werden sollte: Variante 1: die heterogen katalysierte Partialoxidation von H{sub 2}S an Flugstaub mit anschliessender Schwefelabscheidung auf dem Staub und, Variante 2: die nichtkatalysierte Partialoxidation von H{sub 2}S in homogener Gasphase mit anschliessender Schwefelabscheidung in einem Spruehabscheider. Ausgehend von den Versuchsergebnissen der Verfahrensvarianten 1 und 2 wurde zusaetzlich als Verfahrensvariante 3 die heterogen katalysierte Partialoxidation von H{sub 2}S am Festbett untersucht. Diese Versuche orientierten sich an den Rohgasbedingungen der Schlackebadvergasung des SVZ Schwarze Pumpe. Als Festbettmaterialien kamen Herdofenkoks, Berlsaettel und eine, speziell fuer diese Verfahrensvariante entwickelte Aktivkohle Oxorbon CJ, zum Einsatz. Die Eignung des

  16. Characterization of oxidation resistance of stainless steels at high temperature by metallographic examinations and in-situ electrical resistance measurements; Charakterisierung der Oxidationsbestaendigkeit in nichtrostenden Staehlen bei hoher Temperatur durch Metallographische Untersuchungen und In-Situ-Messungen des elektrischen Widerstands

    Energy Technology Data Exchange (ETDEWEB)

    Bruncko, Mihael; Rudolf, Rebeka; Anzel, Ivan [Maribor Univ. (Slovenia). Faculty of Mechanical Engineering; Mehrabi, Kambiz [Pankl Drivetrain Systems GmbH und Co. KG, Kapfenberg (Austria); Kneissl, Albert C. [Leoben Univ. (Austria). Dept. of Physical Metallurgy and Materials Testing

    2013-07-01

    Practically all metals and alloys survive high-temperature exposure by growing oxide scales and/or by precipitation of the oxide particles in the matrix. Formed products can grow in shape of external oxide layers on surfaces, or as discrete oxide particles precipitated in a metal matrix. The first case represents external oxidation, and the other case is called internal oxidation. These processes are very important, because they determine the properties and applicability of metallic materials. Generally, they are undesired, because they cause deterioration of the mechanical properties and decomposition of metallic material. On the other side, the controlled process of external oxidation could be used for formation of protective coatings and the internal oxidation for dispersion strengthening of materials. In this paper we present monitoring of high-temperature oxidation of X12Cr13 stainless steel by in-situ electrical resistance measurements at different annealing temperatures in the air atmosphere. We determined the kinetics of oxide scale formation and its morphology with additional metallographic examination made by optical and scanning electron microscopy. The results of this research work show that in-situ monitoring and characterization of high-temperature oxidation present a strong tool that will contribute to a better fundamental understanding of the phenomena that occur during high-temperature oxidation of metallic materials. (orig.)

  17. Stereoskopische Visualisierung einer Infektion mammalischer Zellen durch pathogene Bakterien

    Science.gov (United States)

    Granseier, Michael; Grassmé, Heike; Gulbins, Erich; Lipinski, Hans-Gerd

    Die Infektion mammalischer Zellen durch pathogene Bakterien ist biologisch immer noch nicht sicher geklärt. Mit Hilfe der Laserscanmikroskopie ist es mittlerweile aber möglich, räumliche Bilddaten von Zellproben zu erstellen, auf denen der Eindringvorgang der Bakterien in das Zellinnere durch verschieden leuchtende Fluoreszenzfarbstoffe visualisiert werden kann. Unter Verwendung bekannter und adaptierter 3D-Rekonstruktionsalgorithmen werden dreidimensionale Visualisierungen von Mikroskopiebildern vorgestellt, mit deren Hilfe die Analyse des Infektionsprozesses erleichtert wird. Dabei hat sich gezeigt, dass mit Oberflächenrekonstruktionsverfahren die Topografie der Zelloberfiäche korrekt dargestellt werden kann, während die Darstellung der Farbstoffverteilungen besser durch ein Texture-Mapping-Verfahren gelingt. Die Rekonstruktionen konnten insbesondere durch den Einsatz von stereoskopischen Visualisierungstechniken detailgenau analysiert werden.

  18. Degradation of organic pollutants in the groundwater by mean of heterogeneous catalytic oxidation and a combined process of catalytic oxidation and aerobic biological degradation; Abbau von organischen Schadstoffen im Grundwasser durch heterogen-katalytische Oxidation und die Verfahrenskombination katalytische Oxidation mit aerob-biologischem Abbau

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, J.; Freier, U.; Wecks, M.; Haentzschel, D. [Inst. fuer Nichtklassische Chemie e.V. an der Univ. Leipzig, Leipzig (Germany)

    2004-07-01

    This project formed part of the SAFIRA joint project (Remediation research in regionally contaminated aquifers), which was coordinated by the project division on ''Post-industry and post-mining landscapes'' of Leizig-Halle Environmental Research Centre. The purpose of the present project was to develop various in situ methods of groundwater remediation and test them on the Bitterfeld model site. The project was focussed on developing a groundwater treatment method on the basis of the oxidative catalytic degradation of the organic pollutants. [German] Das Vorhaben war in den SAFIRA-Projektverbund (Sanierungsforschung in regional kontaminierten Aquiferen), das vom Projektbereich Industrie- und Bergbaufolgelandschaften des Umweltforschungszentrums Leipzig-Halle koordiniert wurde, eingebunden. Innerhalb dieses Vorhabens sollten unterschiedliche in-situ Methoden zur Grundwassersanierung entwickelt und am Modellstandort in Bitterfeld getestet werden. Der Schwerpunkt des Vorhabens bestand in der Entwicklung einer Grundwasserbehandlungstechnologie auf der Basis des oxidativ katalytischen Abbaus der organischen Schadstoffe. (orig.)

  19. Fast lichtschnell durch die Stadt: Visualisierung relativistischer Effekte

    Science.gov (United States)

    Kraus, Ute; Borchers, Marc P.

    2005-03-01

    Eine Computersimulation ermöglicht es uns, mit annähernd Lichtgeschwindigkeit durch die Tübinger Fußgängerzone zu fahren. Was wir dabei sehen, ist verblüffend: Die Häuser vor uns rücken umso weiter in die Ferne, je mehr wir beschleunigen; gleichzeitig erscheinen die Hauskanten in unserer Nähe immer stärker gekrümmt. Der Grund für diese merkwürdigen Bilder ist die so genannte Aberration: Ein und derselbe Lichtstrahl hat für den fahrenden Beobachter eine andere Richtung als für denjenigen, der am Straßenrand steht. Dieser Effekt ist im Alltag klein. Wenn wir aber in der Simulation fast lichtschnell durch die Tübinger Altstadt rasen, ist er dramatisch groß.

  20. Evaluation of lung cancer risk from radon in homes. Smoking plays the important part; Bewertung des Lungenkrebsrisikos durch Wohnungsradon. Lungenkrebsrisiko ausschliesslich durch Rauchen verursacht

    Energy Technology Data Exchange (ETDEWEB)

    Schuettmann, W.

    1999-07-01

    Studies of lung cancer risk from the beginning of the century until today are investigated and evaluated. The result shows that the risk in homes with Radon exposure is determined exclusively by the amount of smoking. Further studies of the lung cancer risk from Radon therefore should exclusively treat with non-smokers. (orig.) [German] Studien zum Lungenkrebsrisiko durch Radon vom Anfang dieses Jahrhunderts bis heute werden untersucht und bewertet. Das Ergebnis zeigt, dass das Lungenkrebsrisiko in Wohnungen mit Radonexpositionen ausschliesslich durch den Umfang des Zigarettenrauchens bestimmt wird. Untersuchungen zur Bewertung des Lungenkrebsrisikos durch Radon sollten daher ausschliesslich bei Nichtrauchern durchgefuehrt werden. (orig.)

  1. Ressourceneffizienz durch Digitalisierung: Vortrag gehalten beim Runden Tisch "Nachhaltige Digitalisierung", Digitalisierung als Motor der Nachhaltigkeit, 15. März 2017, Stuttgart

    OpenAIRE

    Sauer, Alexander

    2017-01-01

    Der Vortrag "Ressourceneffizienz durch Digitalisierung" behandelt folgende Themenkomplexe: - DigitalisierungalsInnovationstreiber - Geschäftsmodell-Innovation - Ressourceneffiziente Produktion - Expertensicht auf Unternehmenspotenziale durch Industrie 4.0

  2. Entgrenzung durch Medien: Internationalisierungsprozesse als Rahmenbedingung der Mediendidaktik

    Directory of Open Access Journals (Sweden)

    Michael Klebl

    2006-07-01

    Full Text Available Die Mediendidaktik ist eine Teildisziplin der Medienpädagogik und hat in den vergangenen Jahren einen enormen Zuwachs an Nachfrage und Bedeutung erfahren. Dieser Bedeutungszuwachs ist bedingt durch den verstärkten Einsatz digitaler Informations- und Kommunikationstechniken in Bildungsprozessen (Stichwort «E- Learning». Der vorliegende Beitrag entwickelt die These, dass die Mediendidaktik ausgehend von medientechnischen Entwicklungen im Kontext von Globalisierung einer Entgrenzung unterworfen ist. Diese Entgrenzung ist Chance und Risiko zugleich. Der vorliegende Beitrag klärt zunächst den Begriff der Entgrenzung. Anhand dreier Phänomene werden Prozesse der Entgrenzung für die Mediendidaktik beschrieben. Ausgehend von der Problematisierung der Prozesse von Entgrenzung werden abschliessend einige Folgerungen für die Mediendidaktik als Teildisziplin der Medienpädagogik zur Diskussion gestellt.

  3. Amerikanisierung durch Internationalisierung: Die Expansion der International Communication Association (ICA

    Directory of Open Access Journals (Sweden)

    Thomas Wiedemann

    2016-12-01

    Full Text Available Basierend auf der Soziologie Bourdieus problematisiert dieser Beitrag die Bemühungen der International Communication Association (ICA, sich über die Öffnung ihrer Führungsetage für Wissenschaftler außerhalb der USA in eine wahrhaft internationale Fachgesellschaft zu verwandeln und der Herausforderung einer global vernetzten Disziplin zu begegnen. Geleistet werden soll so ein kritischer Beitrag zur Selbstreflexion der Kommunikationswissenschaft, zu verstehen als Deutungsangebot und Ausgangspunkt für die wissenschaftliche Diskussion. Die Untersuchung von Habitus und Kapital der 29 ICA-Präsidenten und ICA Fellows aus der internationalen Scientific Community zeigt, dass die weltweit größte kommunikationswissenschaftliche Fachgesellschaft trotz der Ausweitung ihrer Führungsriege immer noch deutlichen US-Einflüssen unterliegt. Die neuen ICAWürdenträger, die für nationale und fachliche Vielfalt stehen sollen, stammen aus Weltregionen, die eine besondere Nähe zu den Vereinigten Staaten auszeichnet, und wurden an US-Universitäten sozialisiert oder stark von der US-amerikanischen Forschungstradition geprägt. Ausnahmen („Einkäufe“ von führenden Vertretern anderer Fachgesellschaften oder alternativer Paradigmen bestätigen die Regel. Die Internationalisierung der ICA-Führungsetage veränderte demzufolge weniger den Machtpol im Fach als vielmehr die Kommunikationswissenschaft weltweit. Zwar gelangten neue Perspektiven ins Zentrum der Disziplin. Im Gegenzug fand jedoch eine Amerikanisierung nationaler Felder statt, allen voran durch ICA Fellows als Vorbilder im Kampf um wissenschaftliches Kapital. Die Bemühungen der ICA, sich durch die Expansion ihrer Führungsriege zu internationalisieren, dürften somit die Machtstrukturen im Fach weiter verfestigt haben.

  4. Phase-shift analysis of pion-nucleon elastic scattering below 1.6 GeV; Analyse en ondes partielles de la diffusion elastique meson {pi} - nucleon au-dessous de 1.6 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Bareyre, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-06-01

    Experimental results of pion-nucleon elastic scattering below 1.6 GeV (total cross sections, angular distributions of elastic scattering and recoil nucleon polarizations) have been described by a partial wave analysis. This analysis has been developed, one energy at a time, with a method of least squares fits. A single solution is extracted by continuity with energy of the different solutions. Resonating behaviour has been clearly established for several partial waves. In addition to these important effects some phase shifts show rapid variations with energy. Present experimental situation does not permit to say whether these variations are due to experimental biases or to physical effects. (author) [French] Les resultats experimentaux de la diffusion elastique meson {pi} - nucleon au-dessous de 1.6 GeV (sections efficaces totales, distributions angulaires de diffusion elastique et de polarisation du nucleon de recul) sont decrits a l'aide d'une analyse en ondes partielles. Cette analyse est developpee energie par energie au moyen d'une methode d'ajustement en moindres carres. Un critere empirique de continuite des solutions en fonction de l'energie a permis d'isoler une solution unique. Des resonances sont clairement etablies pour plusieurs ondes partielles, ainsi que certains petits effets moins caracteristiques. Pour ceux-ci, la situation experimentale presente ne permet pas d'affirmer s'ils sont dus a des effets physiques ou a des biais experimentaux. (auteur)

  5. Etude de la performance des radars hautes-frequences CODAR et WERA pour la mesure des courants marins en presence partielle de glace de mer

    Science.gov (United States)

    Kamli, Emna

    Les radars hautes-frequences (RHF) mesurent les courants marins de surface avec une portee pouvant atteindre 200 kilometres et une resolution de l'ordre du kilometre. Cette etude a pour but de caracteriser la performance des RHF, en terme de couverture spatiale, pour la mesure des courants de surface en presence partielle de glace de mer. Pour ce faire, les mesures des courants de deux radars de type CODAR sur la rive sud de l'estuaire maritime du Saint-Laurent, et d'un radar de type WERA sur la rive nord, prises pendant l'hiver 2013, ont ete utilisees. Dans un premier temps, l'aire moyenne journaliere de la zone ou les courants sont mesures par chaque radar a ete comparee a l'energie des vagues de Bragg calculee a partir des donnees brutes d'acceleration fournies par une bouee mouillee dans la zone couverte par les radars. La couverture des CODARs est dependante de la densite d'energie de Bragg, alors que la couverture du WERA y est pratiquement insensible. Un modele de fetch appele GENER a ete force par la vitesse du vent predite par le modele GEM d'Environnement Canada pour estimer la hauteur significative ainsi que la periode modale des vagues. A partir de ces parametres, la densite d'energie des vagues de Bragg a ete evaluee pendant l'hiver a l'aide du spectre theorique de Bretschneider. Ces resultats permettent d'etablir la couverture normale de chaque radar en absence de glace de mer. La concentration de glace de mer, predite par le systeme canadien operationnel de prevision glace-ocean, a ete moyennee sur les differents fetchs du vent selon la direction moyenne journaliere des vagues predites par GENER. Dans un deuxieme temps, la relation entre le ratio des couvertures journalieres obtenues pendant l'hiver 2013 et des couvertures normales de chaque radar d'une part, et la concentration moyenne journaliere de glace de mer d'autre part, a ete etablie. Le ratio des couvertures decroit avec l'augmentation de la concentration de glace de mer pour les deux types

  6. Optimization of sewage treatment plants through adjustment of the acid capacity; Optimierung von Klaeranlagen durch Saeurekapazitaetseinstellung

    Energy Technology Data Exchange (ETDEWEB)

    Herbst, B.; Soelter, K. [Bundesverband der Deutschen Kalkindustrie e.V., Koeln (Germany)

    1999-07-01

    In many areas with soft water (low water hardness), variations of degradation behaviour are noted in the biological cleaning of municipal and industrial waste water. The use of acidic precipitation agents and processes of biological ammonium oxidation (nitrification) reduce the acid capacity of water. Addition of lime in different forms can prevent this drop in acid capacity. As a new development in this field, lime hydrate can be added in dry form. This form of application dispenses with some of the elements normally installed at sewage treatment plants. Several examples demonstrate the advantages offered by this technique, especially the need for less metal salts to eliminate phosphate. (orig.) [German] In vielen Weichwassergebieten (geringer Wasserhaerte) treten bei der biologischen Reinigung von kommunalen und industriellen Abwaessern Schwankungen des Abbauverhaltens auf. Der Einsatz von sauren Faellmitteln und die Prozesse der biologischen Ammoniumoxidation (Nitrifikation) senken die Saeurekapazitaet des Wassers ab. Durch die Zugabe von Kalk in verschiedenen Dosierformen kann die Saeurekapazitaetsabsenkung verhindert werden. Eine neue Entwicklung auf diesem Gebiet ist die Trockendosierung von Kalkhydrat. Wesentliche Teile der sonst installierten Anlagentechnik sind bei dieser Art der Dosierung nicht mehr notwendig. Anhand von mehreren Beispielen wird erlaeutert, welche Vorteile dieses Verfahren bieten kann, insbesondere bei der Einsparung von Metallsalzen zur Phosphatentfernung. (orig.)

  7. Israelische Public Diplomacy und ihre Wahrnehmung durch deutsche Journalisten

    Directory of Open Access Journals (Sweden)

    Florian Fleischer

    2014-07-01

    Full Text Available Public Diplomacy stellt insbesondere für Staaten in internationalen Konflikten wie Israel ein wichtiges Kommunikationsinstrument dar, um ausländische Bevölkerungen zu erreichen. Der Artikel zeigt die Ergebnisse einer Studie, in der untersucht wurde, wie die israelische Public Diplomacy von deutschen Journalisten aufgenommen und verarbeitet wird. Journalisten kommt dabei eine Schlüsselrolle als Mittler zwischen dem israelischen Staat und der deutschen Bevölkerung zu. In Anlehnung an den Katalog der Public Diplomacy-Maßnahmen von Gilboa (2006 wurde die Relevanz einzelner Maßnahmen für Journalisten erfragt. Die Ergebnisse zeigen, dass persönliche Kontakte für Journalisten nach wie vor eine wichtige Quelle darstellen und nicht von Cyber-Public Diplomacy ersetzt werden können. Staatliche Public Diplomacy wird zwar wahrgenommen, jedoch wird ihre Objektivität bezweifelt, während NGOs und Stiftungen als vertrauenswürdiger eingestuft werden. Des Weiteren wird Israel in der Öffentlichkeit nach wie vor dominierend mit dem Nahostkonflikt identifiziert, was sich nach Meinung der befragten Journalisten auch in Zukunft nicht durch gezielte Öffentlichkeitsarbeit verhindern lässt.

  8. Géochimie des basaltes de l'île de Ua Huka (archipel des Marquises) : variation du taux de fusion partielle et hétérogénéité de la source mantellique

    OpenAIRE

    Ielsch, G.; Caroff, M.; Barsczus, Hans Gustave; Maury, R.C.; Guillou, H.; Guille, G.

    1998-01-01

    L'île de Ua Huka (archipel des Marquises) comporte un volcan-bouclier principal, édifié entre 3,2 et 2,4 Ma, puis immédiatement affecté par un double effondrement caldeirique. Après un arrêt de l'activité volcanique pendant 0,9 Ma, deux petits volcans se sont mis en place au sud-ouest de l'île entre 1,5 et 0,75 Ma. Les différents types de basaltes constituant ces édifices (tholéiites à olivine, basaltes alcalins et basanites) résulteraient de la fusion partielle d'une source chimiquement hété...

  9. Serial co-sputtering. Development of a versatile coating technology and its characterization using the example of rate enhancement of metal oxides by co-doping; Serielles Co-Sputtern. Entwicklung einer flexiblen Beschichtungstechnologie und deren Charakterisierung am Beispiel der Ratenerhoehung von Metalloxiden durch Co-Dotierung

    Energy Technology Data Exchange (ETDEWEB)

    Austgen, Michael

    2011-09-19

    Focus of this work is the design and characterization of a versatile coating system based on magnetron sputter deposition. This technology consists of a rotary target (primary target) that will be sputtered at one position and also can be coated at a different position with a secondary material by another sputter process. This simultaneous operation and the serial order of two sputter processes is the serial co-sputter process. A highly elaborated gas separation allows the operation of the primary sputter process in a reactive gas atmosphere whereas the secondary process can be driven in a non-reactive atmosphere. Compared to conventional co-sputtering the gas separation enables a stable operation of the secondary sputter process even if reactive gas is added to the primary sputter process. To develop an understanding of the process dynamics of serial co-sputtering the rate enhancement of metal oxides by co-doping with heavy atoms has been investigated first. If heavy elements are added to the target material the collision cascades can be reflected back towards the target surface by a more efficient momentum transfer and therefore increase the sputtering rate. The addition of heavy atoms can be achieved by serial co-sputtering. In the secondary sputter process the heavy element will be sputter deposited onto the rotary target. When entering the erosion zone of the primary sputter process the heavy atoms will be partially sputtered away and partially recoil implanted beneath the target surface. The later will contribute to the sputter yield amplification effect described above. In this work the sputter yield amplification effect has been investigated for the metal oxides Al{sub 2}O{sub 3} and TiO{sub 2} by co-doping of a aluminum and titanium rotary target with the heavy element tungsten (Z=74) and bismuth (Z=83). The primary process variables are the O{sub 2}-gas flow which determines the working point of the primary sputtering process, the rotation speed of the

  10. Review: Findeisen, Genia: Frauen in Indonesien: Geschlechtergleichheit durch Demokratisierung? Eine Analyse des Demokratisierungsprozesses aus Frauenperspektive (2008 Buchbesprechung: Findeisen, Genia: Frauen in Indonesien: Geschlechtergleichheit durch Demokratisierung? Eine Analyse des Demokratisierungsprozesses aus Frauenperspektive (2008

    Directory of Open Access Journals (Sweden)

    Carola von der Dick

    2009-04-01

    Full Text Available Review of the monograph: Findeisen, Genia: Frauen in Indonesien: Geschlechtergleichheit durch Demokratisierung? Eine Analyse des Demokratisierungsprozesses aus Frauenperspektive Wettenberg: Johannes Herrmann J&J Verlag, 2008, ISBN 978-3-937983-11-0, 434 pages Besprechung der Monographie: Findeisen, Genia: Frauen in Indonesien: Geschlechtergleichheit durch Demokratisierung? Eine Analyse des Demokratisierungsprozesses aus Frauenperspektive Wettenberg: Johannes Herrmann J&J Verlag, 2008, ISBN 978-3-937983-11-0, 434 Seiten

  11. Multiple benefits through intelligent combination. Economic inventory optimization through the use of photovoltaics; Mehrfachnutzen durch intelligente Kombination. Wirtschaftliche Bestandsoptimierung durch Nutzung von Photovoltaik

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2013-10-15

    By installing a PV system the roof areas are additionally used for power generation. To ensure the operability permanently, they must be carefully planned, built and maintained. Based on three demonstration examples it is shown how inventory optimization can be achieved by maintaining high quality standards (tennis hall Oberthal and Ottweiler, warehouse roof of the building material dealer Lauer). [German] Durch die Installation einer PV-Anlage werden die Dachflaechen zusaetzlich zur Energiegewinnung genutzt. Um die Funktionsfaehigkeit dauerhaft zu gewaehrleisten, muessen sie sorgfaeltig geplant, gebaut und gewartet werden. Anhand von drei Demonstrationsbeispielen (Tennishalle Oberthal und Ottweiler, Lagerhallendach des Baustoffhaendlers Lauer) wird gezeigt, wie die Bestandsoptimierung unter Einhaltung hoher Qualitaetsstandards geloest werden kann.

  12. SAFIRA project B.3.3: in-situ-treatment of contaminated ground water by catalytic oxidation. Final report; Sanierungsforschung in regional kontaminierten Aquiferen (SAFIRA). Projekt B.3.3: In situ-Behandlung von kontaminierten Grundwaessern durch katalytische Oxidation. Teilvorhaben 1: Untersuchungen im Labormassstab. Teilvorhaben 2: Tests in der bench-scale-Anlage und Teilvorhaben 3: Die Erprobung in der Pilotanlage am Modellstandort. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, J.; Haentzschel, D.; Freier, U.; Wecks, M.

    2003-06-27

    A new technology for treatment of contaminated ground water was developed. In this process heterogeneous catalysts (full metal catalyst, mixed oxide catalyst or iron-containing zeolites) in combination with hydrogen peroxide are used. In the reactor catalytic oxidation and aerob biological degradation occur simultaneously. A complete degradation of chlorobenzene was observed in a bench-scale-equipment (2 liter) and also in the pilot plant at the model site located in Bitterfeld (30 liter reactor). The technology can be applied to the ground and waste water treatment. (orig.) [German] Fuer die Behandlung von Grundwaessern, die mit organischen Schadstoffen belastet sind, wurde ein neuartiges Verfahren entwickelt. Bei der katalytischen Oxidation werden heterogene Katalysatoren in Form von Vollmetall-, Mischoxid- und Traegerkatalysatoren in Verbindung mit Wasserstoffperoxid als Oxidationsmittel eingesetzt. In den Katalysereaktoren laufen die heterogen-katalytische Oxidation und der aerob-biologische Abbau nebeneinander ab. Es werden synergistische Effekte erzielt. Mit dem Verfahren wurde in einer bench-scale-Angle (2 Liter) und in der Pilotanlage am Modellstandort in Bitterfeld (30 l Reaktor) der Schadstoff Chlorbenzol vollstaendig umgesetzt. Das Verfahren kann zur Grund- und Abwasserbehandlung eingesetzt werden. (orig.)

  13. Study of the fluctuations of the partial and total radiative widths by neutron capture resonance method; Etude des fluctuations des largeurs radiatives partielles et totales par la capture des neutrons de resonance

    Energy Technology Data Exchange (ETDEWEB)

    Huynh, V D [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-06-01

    Radiative capture experiments by neutron time-of-flight methods have been made for following studies: distribution of partial radiative widths, effects of correlation between different radiative transitions, fluctuations of total radiative widths {gamma}{sub {gamma}} from resonance to resonance, variation of {gamma}{sub {gamma}} with number of mass and the search for the existence of potential capture. Also, some other experiments with the use of neutron capture gamma-rays spectra have been investigated. (author) [French] Par la capture des neutrons de resonance dont les energies sont selectionnees a l'aide de la technique du temps de vol, differents types d'experiences ont ete realisees concernant les etudes des distributions des largeurs radiatives partielles, des effets de correlation entre differentes voies de desexcitation, de la fluctuation des largeurs radiatives totales {gamma}{sub {gamma}} de resonance a resonance, de la variation de la quantite {gamma}{sub {gamma}} en fonction du nombre de masse et de la mise en evidence de l'existence du processus de capture potentielle. Quelques autres applications de l'emploi du spectre de rayons gamma ont egalement ete presentees. (auteur)

  14. Study of the fluctuations of the partial and total radiative widths by neutron capture resonance method; Etude des fluctuations des largeurs radiatives partielles et totales par la capture des neutrons de resonance

    Energy Technology Data Exchange (ETDEWEB)

    Huynh, V.D. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-06-01

    Radiative capture experiments by neutron time-of-flight methods have been made for following studies: distribution of partial radiative widths, effects of correlation between different radiative transitions, fluctuations of total radiative widths {gamma}{sub {gamma}} from resonance to resonance, variation of {gamma}{sub {gamma}} with number of mass and the search for the existence of potential capture. Also, some other experiments with the use of neutron capture gamma-rays spectra have been investigated. (author) [French] Par la capture des neutrons de resonance dont les energies sont selectionnees a l'aide de la technique du temps de vol, differents types d'experiences ont ete realisees concernant les etudes des distributions des largeurs radiatives partielles, des effets de correlation entre differentes voies de desexcitation, de la fluctuation des largeurs radiatives totales {gamma}{sub {gamma}} de resonance a resonance, de la variation de la quantite {gamma}{sub {gamma}} en fonction du nombre de masse et de la mise en evidence de l'existence du processus de capture potentielle. Quelques autres applications de l'emploi du spectre de rayons gamma ont egalement ete presentees. (auteur)

  15. Lipase-katalysierte Synthese strukturierter Triglyceride: Verfahrensoptimierung und Erzeugung selektiver Lipasemutanten durch gerichtete Evolution

    OpenAIRE

    Schmid, Ulrike

    1999-01-01

    In der vorliegenden Arbeit wurde zum einen die Lipase-Katalysierte Synthese strukturierter Triglyceride, zum anderen die Veränderung der Kettenlängenselektivität der slip1-Lipase aus C. rugosa durch gerichtete Evolution untersucht. Besonderes Interesse galt der Synthese von strukturierten Triglyceriden des ABA-Typs, die aufgrund ihrer symmetrischen Struktur zur Therapie von Fettabsorptionsproblemen wie z.B. Pankreasinsuffizienz eingesetzt werden können. Besonderes Interesse galt dabei der ...

  16. Selective oxidation of benzene and cyclohexane using amorphous microporous mixed oxides; Selektive Oxidation von Benzol und Cyclohexan mit amorphen mikroporoesen Mischoxiden

    Energy Technology Data Exchange (ETDEWEB)

    Stoeckmann, M.

    2000-07-01

    Phenol was to be produced by direct oxidation of benzene with environment-friendly oxidants like hydrogen peroxide, oxygen, or ozone. Catalysts were amorphous microporous mixed oxides whose properties can be selected directly in the sol-gel synthesis process. Apart from benzene, also cyclohexane was oxidized with ozone using AMM catalysts in order to get more information on the potential of ozone as oxidant in heterogeneously catalyzed reactions. [German] Ziel dieser Arbeit war die Herstellung von Phenol durch die Direktoxidation von Benzol mit umweltfreundlichen Oxidationsmitteln wie Wasserstoffperoxid, Sauerstoff oder Ozon. Als Katalysatoren dienten amorphe mikroporoese Mischoxide, da deren Eigenschaften direkt in der Synthese durch den Sol-Gel-Prozess gezielt eingestellt werden koennen. Neben Benzol wurde auch Cyclohexan mit Ozon unter der Verwendung von AMM-Katalysatoren oxidiert, um das Potential von Ozon als Oxiationsmittel in heterogen katalysierten Reaktionen naeher zu untersuchen. (orig.)

  17. Transparency and efficiency through plant operations management systems; Transparenz und Effizienz durch Betriebsfuehrungssysteme

    Energy Technology Data Exchange (ETDEWEB)

    Ladage, L. [RWE Power AG, Essen (Germany). Informationsmanagement

    2001-04-01

    Plant operations management systems, being IT application systems, provide integral support of the business processes making up plant operations management. The use of plant operations management systems improves mutually interdependent factors, such as high economic performance, high availability, and maximum safety. Since its commissioning in 1988, the Emsland nuclear power station (KKE) has been run with the IBFS plant operations management system. The work flow management system (WfMS), a module of IBFS, is described as an example of job order processing. IBFS-WfMS is to optimize all processes, thus cutting costs and ensuring that processes are run and documented reliably. Assessing the savings effect achieved through the use of IBFS-WfMS clearly reveals the savings in work/time achieved by the system. These savings are quoted as approx. 4 minutes and DM 10, respectively, per working step, which corresponds to several dozens of manyears or several million DM per annum in the KKE plant under consideration. This result can be extrapolated to other plants. (orig.) [German] Betriebsfuehrungssysteme stuetzen als EDV-Anwendungssystem integral die Geschaeftsprozesse der Kraftwerksbetriebsfuehrung. Durch den Einsatz von Betriebsfuehrungssystemen werden die in gegenseitiger Abhaengigkeit befindlichen Faktoren hohe Wirtschaftlichkeit, hohe Verfuegbarkeit und groesstmoegliche Sicherheit im Verbund gefoerdert. Im Kernkraftwerk Emsland (KKE) wird seit Inbetriebnahme der Anlage im Jahr 1988 das Betriebsfuehrungssystem IBFS eingesetzt. Am Beispiel des Workflowmanagementsystems (WfMS), einem Modul des IBFS, wird die Abwicklung von Arbeitsauftraegen dargestellt. Das IBFS-WfMS soll dabei durch Optimierung aller Prozesse sowohl kostensenkend wirken als auch sicherstellen, dass die Prozesse verlaesslich abgewickelt und dokumentiert werden. Eine Abschaetzung des Einspareffektes des IBFS-WfMS zeigt deutlich die durch das System erzielten Ersparnisse an Arbeits-/Zeitaufwand auf

  18. Ausschöpfung der vollen Leistungsfähigkeit von Sortiersystemen durch neue Einschleustechnik

    OpenAIRE

    Sadowsky, Volker; Semrau, Kai F.

    2012-01-01

    Die Ausschöpfung der vollen Leistungsfähigkeit von Stückgut-Sortiersystemen bedingt eine stetige Zuförderung der Stückgüter über die Einschleusungen zum Sorter. Für Sortiersysteme mit nur einer Einschleusung trifft dies in besonderer Weise zu, da in diesem Fall die maximale Durchsatzleistung des Sorters direkt durch die maximale Durchsatzleistung der Einschleusung begrenzt wird. Im Rahmen dieses Artikels werden unterschiedliche Gestaltungsmöglichkeiten für die Einschleusung am Drehsorter vorg...

  19. Effects of landfills on the limnology of associated running waters; Gefaehrdung von Oberflaechengewaessern durch Altablagerungen

    Energy Technology Data Exchange (ETDEWEB)

    Baier, B. [Hohenheim Univ., Stuttgart (Germany). Inst. fuer Zoologie; Kappus, B. [Hohenheim Univ., Stuttgart (Germany). Inst. fuer Zoologie; Boehmer, J. [Hohenheim Univ., Stuttgart (Germany). Inst. fuer Zoologie; Nill, A. [Hohenheim Univ., Stuttgart (Germany). Inst. fuer Zoologie; Rahmann, H. [Hohenheim Univ., Stuttgart (Germany). Inst. fuer Zoologie

    1997-10-01

    Five small brooks influenced by runoff from landfills were surveyed from May 1993 to March 1994 using chemical and biological methods. Results showed clear impacts on the macroinvertebrate fauna as a result of pollutants in three of the five brooks studied. (orig.) [Deutsch] Im Einflussbereich von Altdeponien wurden fuenf kleine Fliessgewaesser von Mai 1993 bis Maerz 1994 wasserchemisch und biologisch untersucht. Anhand der Untersuchungsergebnisse wurde eine Gefaehrdungsabschaetzung der Oberflaechengewaesser durch die Altablagerungen vorgenommen. Danach waren bei drei der fuenf untersuchten Deponien aufgrund von Schadstoffeintraegen Auswirkungen auf die Makrobenthosfauna der angrenzenden Fliessgewaesser erkennbar. (orig.)

  20. Nitrate removal through combination of nanofiltration and electrocatalysis; Nitratentfernung durch Kombination von Nanofiltration und Elektrokatalyse

    Energy Technology Data Exchange (ETDEWEB)

    Roehricht, M.; Stadlbauer, E.A.; Happel, H. [Fachhochschule Giessen (Germany). Zentrum fuer Umwelttechnik

    1999-07-01

    In a new process combination, nitrate-containing ground water is first of all separated by nanofiltration into a concentrate stream (some 25 %) and a largely nitrate-free permeate (75 %). Then the enriched nitrate in the concentrate is converted into nitrogen by means of electrocatalytic nitrate reduction. Whereas, in nanofiltration, a concentration takes place, electrocatalytic nitrate reduction is a process by which nitrate is converted into elemental nitrogen and, thus, removed. Nanofiltration is a membrane separating process making use of 'open' reverse osmosis membranes, which are characterized by high flow but also reduced retention. (orig.) [German] In einer neuen Verfahrenskombination wird das nitrathaltige Grundwasser zuerst durch Nanofiltration in einen Konzentratstrom (ca. 25%) und ein weitgehend nitratfreies Permeat (75%) aufgeteilt. Im Konzentrat wird dann mittels Elektrokatalytischer Nitratreduktion (EKN) das angereicherte Nitrat zu Stickstoff umgewandelt. Waehrend bei der Nanofiltration eine Aufkonzentrierung erfolgt, wird durch die Elektrokatalytische Nitratreduktion das Nitrat in elementaren Stickstoff umgewandelt und so entfernt. Die Nanofiltration ist ein Membrantrennverfahren, bei dem 'offene' Umkehrosmosemembranen eingesetzt werden, die einen hohen Fluss aber auch eine verminderte Rueckhaltung aufweisen. (orig.)

  1. Automation on computers of the partial area method for the analysis of 's' neutron induced resonances. I. Without interference terms. (1962); Automatisation sur ordinateur de la methode des aires partielle dans l'analyse des resonances induites par les neutrons 's'. I. sans terme d'interference. (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, G; Corge, C R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    This report deals with numerical analysis of transmission resonances induced by 's' wave neutrons in time of flight experiments. The analysis method used is the partial area one. The only case treated here, in this first part, is the one when the interference term can be neglected. Programs and subroutines are thoroughly described, which determine from experimental raw data the resonant transmission, the partial areas, and the resonance parameters. (authors) [French] Le present rapport a pour objet l'analyse numerique sur ordinateur IBM 7090, des resonances dues aux neutrons 's' dans les experiences de transmission par temps de vol, la methode d'analyse utilisee etant la methode des aires partielles. Dans cette premiere partie, seul a ete envisage le cas ou le terme d'interference peut etre neglige. On y trouvera une description detaillee des programmes et sous programmes elabores pour determiner les transmissions resonantes avec leur trace, a partir des donnees experimentales brutes, les aires partielles afferentes ainsi que les parametres caracteristiques des resonances. (auteurs)

  2. Environmental pollution caused by coal mining and utilization in China; Umweltbelastungen durch Kohlefoerderung und -nutzung in China

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Fuchen [Guangdong Ocean Univ., Zhanjiang (China). Dept. of Scientific Research Management

    2013-07-15

    After the BP Statistical Review of World Energy of 2010 45.6% of coal production and 46.9% of coal consumption in the world in 2009 are accounted for China. The large-scale coal production and use cause major environmental impacts. A large environmental impact is through the emission of some unavoidable reaction products (for example waste gas, waste heat) that affect and damage the ecosystem. A steady influence can lead to long-term climate changes and medium term damage to the ecosystem. Other environmental impacts occur during mining of coal by the change in the water balance and the transformation of the landscape (surface mining, spoil tips). The environmental problems caused by coal mining and utilization can not be ignored in China. [German] Nach der BP-Statistik der Weltenergie 2010 sind 45,6% der Kohleproduktion und 46,9% des Kohleverbrauchs in der Welt im Jahr 2009 auf China entfallen. Die grossangelegte Kohlefoerderung und -verwendung fuehren zu grossen Umweltbelastungen. Eine grosse Umweltbeeinflussung erfolgt durch die Emission von zum Teil unvermeidbaren Umsetzungsprodukten (zum Beispiel Abgas, Abwaerme), die das Oekosystem beeinflussen und schaedigen. Eine stetige Beeinflussung kann langfristig zu den Klimaveraenderungen und mittelfristig zur Schaedigung des Oekosystems fuehren. Weitere Umweltbelastungen erfolgen beim Abbau der Kohle durch die Veraenderung des Wasserhaushalts und durch die Umgestaltung der Landschaft (Tagebau, Abbauhalden). Die Umweltprobleme, die durch die Kohlefoerderung und -nutzung verursacht werden, koennen in China nicht ignoriert werden.

  3. Deutsch Durch Audio-Visuelle Methode: An Audio-Lingual-Oral Approach to the Teaching of German.

    Science.gov (United States)

    Dickinson Public Schools, ND. Instructional Media Center.

    This teaching guide, designed to accompany Chilton's "Deutsch Durch Audio-Visuelle Methode" for German 1 and 2 in a three-year secondary school program, focuses major attention on the operational plan of the program and a student orientation unit. A section on teaching a unit discusses four phases: (1) presentation, (2) explanation, (3)…

  4. Decontamination of contaminated soils by microwave heating; Dekontaminierung verseuchter Boeden durch Mikrowellenheizung

    Energy Technology Data Exchange (ETDEWEB)

    Pauli, Mario

    2011-07-01

    The paper describes a system for the thermal decontamination of contaminated soils by microwaves. In addition to the determination of the dielectric material parameters of different soils, a focus is on antennas for the efficient coupling of the microwaves into the ground. The developed simulation model takes into account the electromagnetic-thermal interaction and makes it possible to predict optimal plant configuration, duration and costs of a sanitation measure in advance. [German] Die Arbeit beschreibt ein System zur thermischen Dekontaminierung verseuchter Boeden durch Mikrowellen. Neben der Bestimmung der dielektrischen Materialparameter verschiedener Boeden liegt ein Schwerpunkt auf Antennen zur effizienten Einkopplung der Mikrowellen in den Boden. Das entwickelte Simulationsmodell beruecksichtigt die elektromagnetisch-thermische Wechselwirkung und ermoeglicht es, bereits im Vorfeld optimale Anlagenkonfiguration, Dauer und Kosten einer Sanierungsmassnahme vorherzusagen.

  5. Auto-ignition generated combustion. Pt. 2. Thermodynamic fundamentals; Verbrennungssteuerung durch Selbstzuendung. T. 2. Experimentelle Analyse

    Energy Technology Data Exchange (ETDEWEB)

    Guibert, P. [Paris-6 Univ. (France). Lab. de Mecanique Physique; Morin, C. [Paris-6 Univ. (France); Mokhtari, S.

    2004-02-01

    The combustion initiation by auto-ignition demonstrates benefits in NO{sub x} reduction and in process stability for both spark-ignited and compression ignited engines. Based on the better thermodynamic particularities of the auto-ignition, which have been presented in the first part, the characteristics of this process are demonstrated in the second part by experimental analysis. For comparison with similar studies, the analyses have been carried out in base of a two stroke loop scavenged spark-ignition single cylinder engine. (orig.) [German] Die Steuerung der Verbrennung durch Selbstzuendung zeigt Vorteile bezueglich Senkung der NO{sub x}-Emission und Prozessstabilitaet, sowohl bei Otto- als auch bei Dieselmotoren. Auf Grundlage der thermodynamischen Besonderheiten der Selbstzuendvorgaenge, die im ersten Teil praesentiert wurden, erfolgt im zweiten Teil eine experimentelle Betrachtung der Prozesscharakteristika. Zur Vergleichbarkeit mit aehnlichen Untersuchungen wird die experimentelle Analyse auf Basis eines Zweitakt-Einzylinder-Ottomotors mit Umkehrspuelung durchgefuehrt. (orig.)

  6. Effects of sorption agents on heavy metal release form incinerator slag; Laesst sich die Freisetzung von Schwermetallen aus MVA-Schlacken durch Zugabe von Sorbenten veraendern?

    Energy Technology Data Exchange (ETDEWEB)

    Heiser, U. [Johannes Gutenberg-Univ. Mainz, Mainz (Germany); Kersten, M. [Johannes Gutenberg-Univ. Mainz, Mainz (Germany). Inst. fuer Geowissenschaften

    2003-11-01

    It was investigated inhowfar additions of sorption agents will influence the solution of heavy metals in incinerator slag. [German] Es wurde untersucht, ob nicht durch Zugabe bestimmter Stoffe zur Muellschlacke die Loesung von Schwermetallen beschleunigt werden kann. (orig.)

  7. Remediation of heavy-metal contaminated sediments by means of bioleaching. Study: project results - economic efficiency - market assessment. Final report; Reinigung schwermetallbelasteter Sedimente durch Bioleaching. Studie: Projektergebnisse - Wirtschaftlichkeit - Marktbewertung. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Loeser, C; Zehnsdorf, A; Hoffmann, P; Seidel, H; Schmerold, R

    2002-07-01

    Sedimente mit Sauerstoff in Kontakt, gehen die Schwermetalle durch mikrobielle Oxidations- und Versauerungsprozesse teilweise in Loesung. Dieses natuerliche Bioleaching, welches unkontrolliert ein Gefahrenpotential fuer die Umwelt darstellt, soll durch Aktivierung der autochthonen schwefeloxidierenden Bakterien (z.B. Thiobacilli) beschleunigt und zur Reinigung der Sedimente genutzt werden. Ziel ist es, ein naturnahes Verfahren zur Sedimentdekontamination unter Nutzung des natuerlichen biologischen Solubilisierungspotentials bereitzustellen. Die gereinigten Sedimente sollen in den Stoffkreislauf als Bodensubstrat zurueckgefuehrt werden. Die Verfahrensentwicklung erfolgte am Beispiel von hochbelasteten Sedimenten der Weissen Elster aus dem Suedraum Leipzig. Aus oekonomischen Gruenden soll das Bioleaching der Schwermetalle durch Festbettlaugung nach dem Perkolationsprinzip erfolgen. Das Verfahren erfordert mehrere Prozessstufen. Der Schwerpunkt der Untersuchungen im Labor- und Technikumsmassstab lag auf der Erarbeitung und technischen Umsetzung von Massnahmen zur Beschleunigung der Metallsolubilisierung. (orig.)

  8. Komplexitätsbeherrschung in der wertschöpfungspartnerschaftsübergreifenden Produktspezifikationserstellung bei unvollkommenen Informationen durch Simplifizierungsregeln

    OpenAIRE

    Ludwig, Ralf

    2005-01-01

    Probleme/Forschungsfragen: Ein stetiger Komplexitätsanstieg des Produktes und der Produktentwicklungsumgebung erschweren in Wertschöpfungspartnerschaften das Erreichen einer gemeinsamen Win-Win-Situation. Bei der frühen Erarbeitung der Produktauslegung oder im Rahmen der Produktspezifikationserstellung ist durch die hohe Komplexität von Entwicklungsaufgabe und -umgebung eine umfassende gesamtheitliche Berücksichtigung der wirtschaftlichen Erfolgsdeterminanten nur sehr begrenzt möglich. Ein...

  9. Objektverfolgung durch Fusion von Radar- und Monokameradaten auf Merkmalsebene für zukünftige Fahrerassistenzsysteme

    OpenAIRE

    Liu, Feng

    2010-01-01

    Die vorliegende Arbeit beschreibt eine neuartige Objektverfolgung durch Fusion von Radar- und Monokameradaten auf Merkmalsebene. Dabei werden zuerst die statistischen Fehlermodelle der Sensoren analysiert. Anschließend wird ein neues Assoziationsverfahren auf Basis der PDA-Methodik untersucht. Der Schwerpunkt dieser Arbeit ist die Behandlung der Objektdynmaik mit Hilfe eines adaptiven IMM-Filters. Schließlich wird die Thematik Objektklassifikation sowie Gassenbreiteschätzung beleuchtet.

  10. Heating power stations - influencing costs by organisational measures; Heizkraftwerke - Kostenbeeinflussung durch organisatorische Massnahmen

    Energy Technology Data Exchange (ETDEWEB)

    Riedlinger, R.A.

    1993-12-31

    The products of district heating and, in the foreseeable future also electrical power, must compete in the market with low prices. Low prices, which still provide a profit, are only possible based on low costs. Low costs are achieved by cost control. The basis for cost control is transparency of costs. Mainly organisational measures were proposed and described. From the individual stages of the organisation, the organisational build-up is obtained, the important feature of which is the allocation of competence to make decisions. (orig./KO) [Deutsch] Die Produkte Fernwaerme und in absehbarer Zeit auch elektrische Energie, muessen sich im Markt mit niedrigen Preisen behaupten. Niedrige Preise, die trotzdem einen Gewinn erbringen sollen, sind nur auf der Basis niedriger Kosten moeglich. Niedrige Kosten erreicht man durch Kostensteuerung, Controlling. Grundlage der Kostensteuerung ist Kostentransparenz. Es wurden im wesentlichen ablauforganisatorische Massnahmen vorgeschlagen und beschrieben. Aus den einzelnen Stationen der Ablauforganisation ergibt sich letztendlich die Aufbauorganisation, deren wesentliches Merkmal die Zuordnung von Entscheidungskompetenz ist. (orig./KO)

  11. Processing of maize plants by rotary kiln pyrolysis; Veredlung von Maispflanzen durch Pyrolyse im Drehrohrreaktor

    Energy Technology Data Exchange (ETDEWEB)

    Klose, W.; Wiest, W. [Kassel Univ. (Gesamthochschule) (Germany). Inst. fuer Thermische Energietechnik

    1996-12-31

    The fuel quality of maize plants is to be characterized by short, elementary and thermonalysis. The plants will be pyrolyzed in order to facilitate transport and storage. The formal kinetic parameters of three parallel reactions describing solid matter decomposition are defined by means of TG-DSC, and the reaction enthalpy is measured. Pyrolysis experiments in a rotary kiln converter in the kg range show a strong dependence of the product spectrum on process temperature. In particular, the pyrolysis gas yield increases with temperature at the expense of pyrolysis oil and water. (orig) [Deutsch] Zur energetischen Nutzung von Kulturpflanzen wird die brennstofftechnische Charakterisierung von Maispflanzen durch Kurz-, Elementar- und Thermoanalyse durchgefuehrt. Zur Reduzierung des Aufwands fuer Transport und Lagerung sollen die Pflanzen pyrolysiert weren. Mit Hilfe der TG-DSC werden formalkinetische Parameter von drei Parallelreaktionen zur Beschreibung der Feststoffzersetzung bestimmt und die Reaktionsenthalpie gemessen. Pyrolyseversuche in einem Drehrohrreaktor im Kilogramm-Massstab ergeben eine starke Abhaengigkeit des Produktspektrums von der Prozesstemperatur. Insbesondere steigt die Pyrolysegasausbeute auf Kosten der Bildung von Pyrolyseoel und Wasser mit der Temperatur stark an. (orig)

  12. Processing of maize plants by rotary kiln pyrolysis; Veredlung von Maispflanzen durch Pyrolyse im Drehrohrreaktor

    Energy Technology Data Exchange (ETDEWEB)

    Klose, W; Wiest, W [Kassel Univ. (Gesamthochschule) (Germany). Inst. fuer Thermische Energietechnik

    1997-12-31

    The fuel quality of maize plants is to be characterized by short, elementary and thermonalysis. The plants will be pyrolyzed in order to facilitate transport and storage. The formal kinetic parameters of three parallel reactions describing solid matter decomposition are defined by means of TG-DSC, and the reaction enthalpy is measured. Pyrolysis experiments in a rotary kiln converter in the kg range show a strong dependence of the product spectrum on process temperature. In particular, the pyrolysis gas yield increases with temperature at the expense of pyrolysis oil and water. (orig) [Deutsch] Zur energetischen Nutzung von Kulturpflanzen wird die brennstofftechnische Charakterisierung von Maispflanzen durch Kurz-, Elementar- und Thermoanalyse durchgefuehrt. Zur Reduzierung des Aufwands fuer Transport und Lagerung sollen die Pflanzen pyrolysiert weren. Mit Hilfe der TG-DSC werden formalkinetische Parameter von drei Parallelreaktionen zur Beschreibung der Feststoffzersetzung bestimmt und die Reaktionsenthalpie gemessen. Pyrolyseversuche in einem Drehrohrreaktor im Kilogramm-Massstab ergeben eine starke Abhaengigkeit des Produktspektrums von der Prozesstemperatur. Insbesondere steigt die Pyrolysegasausbeute auf Kosten der Bildung von Pyrolyseoel und Wasser mit der Temperatur stark an. (orig)

  13. Mechatronics in the car: success through efficient methodological development; Mechatronik im Kraftfahrzeug: Erfolg durch effiziente Entwicklungsmethodik

    Energy Technology Data Exchange (ETDEWEB)

    Dieterle, W.; Dilger, E. [Bosch (R.) GmbH, Gerlingen (Germany). Zentralbereich Forschung und Vorausentwicklung; Buerger, K.G. [Bosch (R.) GmbH (Germany)

    2001-04-01

    The ever increasing requirements with respect to fuel consumption, emissions as well as safety and comfort necessitate ever increasing complex functionalities in the car. They are realized, as a rule, by a combination of mechanics, hydraulics, electrics/electronics and, more and more, software. In the past, the development of the various electric/electronic, mechanical or hydraulic components tended to happen at separate levels, nowadays the focus is more on a comprehensive approach to the overall system. In this context, the integrated development of 'mechatronic' components, including the respective software, leads to a targeted solution. (orig.) [German] Staendig steigende Anforderungen hinsichtlich Kraftstoffverbrauch, Emissionen sowie Sicherheit und Komfort bedingen immer komplexere Funktionalitaeten im Kraftfahrzeug. Sie werden in der Regel durch eine Kombination von Mechanik, Hydraulik, Elektrik/Elektronik und zunehmend auch Software realisiert. Nachdem in der Vergangenheit die Entwicklung meist noch auf getrennten Ebenen verlief, steht heute ein uebergreifender, das Gesamtsystem umfassender Ansatz im Vordergrund. Dieser Beitrag der Robert Bosch GmbH berichtet ueber aktuelle Mechatronik-Entwicklungen. Dabei sorgt die integrierte Entwicklung der 'mechatronischen' Komponenten unter Einbezug der zugehoerigen Software fuer eine zielgerichtete Loesung. (orig.)

  14. Biosorption of heavy metals by immobilized microalgae; Biosorption von Schwermetallen durch immobilisierte Mikroalgen

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, A.; Bunke, G.; Goetz, P.; Buchholz, R. [Technische Univ. Berlin (Germany). Fachgebiet Bioverfahrenstechnik

    1999-07-01

    . Durch geeignete Versuche muessen die verschiedenen Stofftransportwiderstaende (Filmwiderstand, Diffusionswiderstand im Innern der Partikel) voneinander entkoppelt werden, damit eine Bestimmung derselben ermoeglicht wird. (orig.)

  15. Continuous high-temperature recycling of waste by the Thermoselect process; Unterbrechungsloses Hochtemperaturrecycling - Abfallveredelung durch Thermoselect

    Energy Technology Data Exchange (ETDEWEB)

    Stahlberg, R [Thermoselect Engineering S.r.l., Verbania (Italy)

    1998-09-01

    Based on the experience with the Thermoselect plant at Fondotoce, Italy (100 Mg/d), which was commissioned in 1992, a 225,000 Mg/a plant with three units (720 Mg/d) is being constructed at Karlsruhe, Germany. The plant is scheduled for commissioning in 1998. The contribution presents the product balance, the approved emission levels, and the energy uses envisaged for the Karlsruhe project. Final product quality data and energy yields illustrate the differences from conventional thermal processes. An ecobalance comparing the Thermoselect process with grate furnaces shows that water, soil and air pollution is much reduced by the new Termoselect process. Apart from high product quality, the plant also has the advantage of reduced dumping cost and no long-term ecological hazards. (orig./SR) [Deutsch] Auf Basis der grosstechnischen Erfahrung mit einer seit 1992 in Fondotoce (Italien) betriebenen THERMOSELECT-Anlage (Kapazitaet 100 Mg/d), Restmuell umweltgerecht zu behandeln, wird 1998 der Aufbau einer 225.000 Mg/a-Anlage mit 3 Linien (720 Mg/d) in Karlsruhe (Deutschland) abgeschlossen. Die Produktebilanz und die genehmigten Emissionswerte sind in dem Artikel belegt. Gezeigt wird die fuer das Projekt Karlsruhe vorgesehene Energienutzung. Die Endprodduktqualitaeten und die Energieausbeute verdeutlichen die Unterschiede zu bisherigen konventionellen thermischen Verfahren. Eine erarbeitete Oekobilanz mit einem Vergleich von THERMOSELECT und Rostfeuerung zeigt die deutlich geringe Belastung der Umweltkompartimente Wasser, Boden und Luft durch das neue THERMOSELECT-Verfahren. Neben hohen Produktqualitaeten wird - verglichen mit traditionellen Techniken - ein deutlich verringerter Entsorgungspreis erreicht, wobei gleichzeitig oekologische Belastungen auszuschliessen sind. (orig./SR)

  16. Automation on computer of the partial area method in the analysis of resonances induced by 'S' neutrons 2. with an interference term and extension of the method to the treatment of multi resonances (1963); Automatisation sur ordinateur de la methode des aires partielles dans l'analyse des resonances induites par les neutrons ''S''. 2, avec terme d'interference et extension de la methode au traitement des multiresonances (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, G; Corge, C R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    This report deals with the numerical analysis on an I.B.M. 7090 computer of transmission resonances induced by 's' wave neutrons in time of flight experiments. The analysis method used is the partial area one. In this second part the interference term is taken into account. Modifications have been made in the programs and subroutines described in the first part, to determine the resonant transmissions from experimental raw data, and the relating partial areas. Also programs and subroutines are thoroughly described, which estimate the resonance parameters. The field of the partial area method has been extended to cover the case where several resonances have to be treated simultaneously, provided they do not interfere. (authors) [French] Le pretent rapport a pour objet l'analyse numerique sur ordinateur I.B.M. 7090 des resonances dues aux neutrons ''s'' dans les experiences de transmission par temps de vol, la methode d'analyse utilisee etant la methode dea aires partielles. Dans cette deuxieme partie il a ete tenu compte du terme d'interference. On y trouvera une description des amenagements apportes aux programmes et sous-programmes decrits dans la premiere partie pour determiner les transmissions interfero-resonnantes a partir des donnees experimentales brutes et les aires partielles afferentes. Sont egalement decrits les programmes et sous-programmes necessaires au calcul des parametres caracteristiques des resonances. Le domaine d'application de la methode a ete etendu au traitement simultane de plusieurs resonances groupees n'interferant pas entre elles. (auteurs)

  17. Formation of formaldehyde in biogas-engines and methods for reducing these emissions by exhaust-gas after-treatment; Entstehung von Formaldehydemissionen in Biogasmotoren und deren Verminderung durch inner- und nachmotorische Massnahmen

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Markus; Wachtmeister, Georg; Prager, Maximilian [TU Muenchen (Germany). Lehrstuhl fuer Verbrennungskraftmaschinen

    2011-07-01

    (BMU) following a resolution by the German Federal Parliament and attended by a Working Group of the Forschungsvereinigung Verbrennungskraftmaschinen e.V (FVV, Research Association for Combustion Engines). (orig.) [German] In der Vergangenheit wurden an Biogasmotoren immer wieder Grenzwertueberschreitungen der in der Technischen Anweisung zur Reinhaltung der Luft (TA Luft) limitierten Formaldehydemissionen festgestellt. Fuer die zukuenftige Einhaltung dieses Grenzwertes an bestehenden und neuen Anlagen wurden am Lehrstuhl fuer Verbrennungskraftmaschinen der Technischen Universitaet Muenchen im Rahmen des FVV-Forschungsvorhabens 918 die Ursachen und die Moeglichkeiten zur innermotorischen Verminderung dieser Emissionen untersucht. Dabei zeigte sich, dass die Formaldehydemissionen nur sehr eingeschraenkt durch innermotorische Massnahmen verringert werden koennen, ohne Wirkungsgrad und Stickoxidemissionen negativ zu beeinflussen. Dies und eine zusaetzliche Verschaerfung der Grenzwerte im Januar 2009 durch LAI-Beschluss machen den Einsatz von Abgasnachbehandlungstechniken notwendig. Wegen der fehlenden Datenbasis ueber das Langzeitverhalten solcher Systeme im Biogasbetrieb wurden deshalb in einem weiteren Vorhaben zwei Modellanlagen mit unterschiedlichen Technologien zur Abgasnachbehandlung ueber sechs Monate hinweg hinsichtlich ihrer Formaldehydemissionen ueberwacht. Im Hinblick auf die aktuelle Klimadebatte und die Klimawirksamkeit von Methan, die eine zukuenftige Begrenzung dieser Emissionen erwarten laesst, wurden darueber hinaus auch die Methanemissionen dieser Anlagen untersucht. Die Untersuchungen zeigten, dass beide betrachteten Abgasnachbehandlungstechnologien, Regenerative Thermische Oxidation (RTO) und Oxidationskatalysator (Oxi-Kat) grundsaetzlich geeignet sind, die geltenden Formaldehydgrenzwerte sicher zu unterschreiten. Es wurde jedoch auch klar, dass weiterer Forschungsbedarf hinsichtlich der Dauerhaltbarkeit des Oxi-Kats und dem Instationaerbetrieb des RTO

  18. Untersuchungen der Narbenqualität nach unterschiedlichen Verfahren des Wundverschlusses und der Wundbehandlung durch autologe Hauttransplantation

    OpenAIRE

    Zeplin, Philip Helge

    2005-01-01

    Die qualitative und quantitative Narbenqualitätsmessungen im Verlauf der Wundheilung ist von großer Bedeutung, da durch sie Einflussgrößen, die mit hoher Wahrscheinlichkeit zu pathologischen Narbenformationen führen, frühzeitig erkannt werden könnten und Rückschlüsse auf die jeweils angewandten Techniken und Materialien zulassen würden. Dass für die Analyse der Heilung von Schnitt- und Defektwunden objektive Messungen unabdingbar sind, sollte am Beispiel des Göttinger Miniaturschweins gezeigt...

  19. Microbiological studies in enhanced sewage sludge degradation through cell membrane break-up; Mikrobiologische Untersuchungen zum verbesserten Klaerschlammabbau durch Zellaufschluss. Mechanische und thermische Behandlung von Schlaemmen

    Energy Technology Data Exchange (ETDEWEB)

    Battenberg, S.; Naeveke, R. [Gesellschaft fuer Biotechnologische Forschung mbH, Braunschweig (Germany). Bereich Mikrobiologie

    1999-07-01

    Mechanical disintegration breaks up the flake structure of excess sludge and solubilizes organic constituents. Bacterial cells are rendered soluble. Thermal conditioning of excess sludge, too, can release sludge constituents. This makes for enhanced and accelerated hydrolysis of polymeric sludge constituents in subsequent anaerobic processing. The yield of useful biogas is increased. (orig.) [German] Durch die mechanische Desintegration von Ueberschussschlamm wird die Flockenstruktur zerschlagen und organische Inhaltsstoffe werden in Loesung gebracht. Bakterienzellen werden aufgeschlossen. Auch durch eine thermische Behandlung von Ueberschussschlamm koennen Schlamminhaltsstoffe freigesetzt werden. Dadurch wird bei einer anschliessenden anaeroben Behandlung die Hydrolyse der polymeren Schlamminhaltsstoffe gefoerdert und beschleunigt. Die Ausbeute an verwertbarem Biogas wird gesteigert. (orig.)

  20. Energy saving by hot operating bearings in high temperature kilns. Final report; Energieeinsparung durch Heisslager in Hochtemperaturanlagen. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Maier, H.R.

    2003-07-01

    The project intended to show that ceramic sliding bearings will ensure longer life, energy and cost savings, reduced environmental pollution, and functional improvements. Ceramic sliding bearings were tested at high temperatures of up to 1400 C and low sliding rates, with and without lubrication. High-temperature test stands were constructed in the two partner institutes and adapted to the specifications of the industrial partners concerning the parameters to be investigated. (orig.) [German] Ziel des Forschungsvorhabens 'Energieeinsparung durch Heisslager in Hochtemperaturanlagen' (EHIH) ist nachzuweisen, dass durch den Einsatz von keramischen Gleitlagern im Hochtemperaturbereich Standzeiterhoehungen, Energie- und Kosteneinsparungen, Umweltentlastungen und Funktionsverbesserungen moeglich sind. Auf der Basis der Anforderungsprofile der Industrie- und Forschungspartner waren umfangreiche Verschleisstests keramischer Gleitlager bei hohen Temperaturen (bis 1400 C) sowie niedrigen Gleitgeschwindigkeiten ohne und mit Feststoff-Schmierung vorgesehen. Hierzu wurden an beiden beteiligten Instituten Hochtemperatur-Pruefstaende aufgebaut, die den Anforderungen der jeweiligen Industriepartner hinsichtlich der zu testenden Lagerparameter (Drehzahl, Flaechenpressung, Temperaturprofile, etc.) angepasst wurden. (orig.)

  1. Pollution and pollution tolerance in the case of polycyclic aromatic hydrocarbons (PAH); Belastung durch Polyzyklische aromatische Kohlenwasserstoffe (PAK)

    Energy Technology Data Exchange (ETDEWEB)

    Renger, M.; Mekiffer, B. [Technische Univ. Berlin (Germany). Inst. fuer Oekologie-Bodenkunde

    1997-12-31

    The purpose of the present follow-up project was to examine the contamination with polycyclic aromatic hydrocarbons (PAH) of different anthropogenic urban soils including clay soils containing demolition waste, household waste, ash, and residues from a coking plant. A further task was to analyse, or infer from other part-projects, standard soil parameters such as organic carbon content, pH, and anion levels in order to clarify any relationships between PAH contamination and the more easily determinable soil characteristics. Furthermore, the sorption behaviour for PAH of selected anthropogenic urban soils was to be characterised by means of batch experiments. [Deutsch] Im Rahmen des Anschlussvorhabens sollte die Kontamination von anthropogenen Stadtboeden- darunter Truemmerschutt-, Hausmuell-, Asche- sowie Kokereilehmboden- durch polyzyklische aromatische Kohlenwasserstoffe (PAK) untersucht werden. Zusaetzlich sollten die bodenkundlichen Standardparameter Corg, pH-Wert, Anionengehalte und KAKpot analysiert bzw. von den anderen Teilvorhaben uebernommen werden, um Zusammenhaenge zwischen der PAK-Kontamination und relativ leicht zu bestimmenden bodenkundlichen Kennwerten klaeren zu koennen. Das Sorptionsverhalten ausgewaehlter anthropogener Stadtboeden fuer PAK sollte durch Batchversuche charakterisiert werden. (orig./SR)

  2. Verbesserung der Lebensqualität bei Kinderwunsch-Behandlung durch den Gebrauch patientenfreundlicher Follitropin-Fertigpens

    Directory of Open Access Journals (Sweden)

    Bitzer J

    2011-01-01

    Full Text Available Zur Behandlung des unerfüllten Kinderwunsches unterziehen sich viele Frauen einer assistierten Reproduktionstherapie mit ovarieller Stimulation. Dazu erfolgen tägliche subkutane Injektionen mit Gonadotropinen, welche die Patientinnen eigenständig durchführen können. Häufig haben Patientinnen dabei Angst vor Spritzen und injektionsbedingten Schmerzen. Die vorliegende Beobachtungsstudie zum Einfluss der Anwendung des Follitropin alfa-Fertigpens (Gonal-f®-Pen auf die Lebensqualität der Patientinnen zeigt die Ergebnisse einer Befragung von 170 Frauen zu Angst und Zufriedenheit mit diesem Applikationssystem. Die Erfahrungen wurden vor und nach den Behandlungszyklen auf numerischen Analogskalen quantifiziert und nachfolgend verglichen. Die Studie ergab, dass durch die Verwendung des Gonal-f®-Pens die Angst vor der Injektion und vor Schmerzen signifikant abnahm. Zudem waren die Patientinnen mit dem Applikationssystem äußerst zufrieden.

  3. Energy conservation by technical means: the control systems matter.; Energiesparen durch technische Hilfsmittel: auf die Regelkreise kommt es an.

    Energy Technology Data Exchange (ETDEWEB)

    Benecke, J. [Verein Deutscher Ingenieure (VDI), Muenchen (Germany)

    2000-07-01

    The new German regulation on energy conservation in buildings (draft) offers certain flexibility for choosing the quality of the building envelope (thermal resistance and air tightness) and of the HV equipment (AC not considered) in order to balance and minimize the yearly heating-energy demand. Up to now, there was little consideration given to control systems which are able to assist the inhabitants in using heating and ventilation efficiently. The performance of such systems is being discussed. (orig.) [German] In Deutschland betraegt der Anteil der Raumheizenergie am Endenergieverbrauch rund 35%; ihr Anteil am Endenergieverbrauch der Haushalte und Kleinverbraucher betraegt rund 76%. Die Vorgaben der bisherigen Waermeschutzverordnungen und der geplanten Energieeinsparverordnung veranschaulichen das Energieeinsparpotential, das durch effizientere Energienutzung im Gebaeudebereich erschlossen werden kann. (orig.)

  4. Contrast generation in the nuclear-spin tomography by pulsed ultrasound; Kontrasterzeugung in der Kernspintomographie durch gepulsten Ultraschall

    Energy Technology Data Exchange (ETDEWEB)

    Oehms, Ole Benjamin

    2009-07-10

    In the framework of this thesis a combined method of ultrasound and nuclear-spin tomography is presented. Via ultrasound pulses by the sound-radiation force in liquids and tissue phantoms motions are generated, which depend on ther viscoelastic properties. This motions are made visible by a motion-sensitive tomograph sequence in the phase image of the tomograph in form of a phase change. The first measurements on simple phantoms and liquids are presented. [German] Im Rahmen dieser Arbeit wird eine kombinierte Methode aus Ultraschall und Kernspintomographie vorgestellt. Ueber Ultraschallpulse werden durch die Schallstrahlungskraft in Fluessigkeiten und Gewebephantomen Bewegungen erzeugt, die von den viskoelastischen Eigenschaften abhaengen. Diese Bewegungen werden mit einer bewegungssensitiven Tomographensequenz im Phasenbild des Tomographen in Form einer Phasenaenderung sichtbar gemacht. Die ersten Messungen an einfachen Phantomen und Fluessigkeiten werden praesentiert. (orig.)

  5. Persistent environmental pollutants. Detoxification by means of fungi; Persistente Umweltschadstoffe. Detoxifizierung durch Pilze

    Energy Technology Data Exchange (ETDEWEB)

    Sietmann, Rabea; Schauer, Frieder [Ernst-Moritz-Arndt-Universitaet, Greifswald (Germany). Inst. fuer Mikrobiologie

    2010-01-15

    Microorganisms either may use environmental pollutants as a source of carbon or attack pollutants oxidatively in the presence of a growth substrate. Furthermore, accumulated toxic products partly can be removed from a cell and oxidized or mineralized by microorganisms. The structural chemical analysis of the accumulated metabolites is performed by means of high-performance liquid chromatography (HPLC), gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). This analysis supplies information on the mechanism of degradation of the environmental pollutants. Under this aspect, the authors of the contribution under consideration report on the use of fungi (aspergillus, candida, cunninghamella, fusarium, mucor, paecilomyces, penicillium, pycnoporus, trametes, trichosporon) in the degradation of biphenyl and its derivatives. The following mechanisms of degradation are discussed: Primary oxidation, hydroxylation, ring scission, formation of conjugates, oligomerisation and dehalogenation.

  6. Inhibitor efficiency in long-time protection of steel tanks for the chemical surface preparation against local corrosion by process solutions containing hydrochloric acid; Inhibitorwirksamkeit beim Langzeitschutz von Stahlbehaeltern fuer die chemische Oberflaechenvorbereitung gegen oertliche Korrosion durch salzsaeurehaltige Prozessloesungen

    Energy Technology Data Exchange (ETDEWEB)

    Stieglitz, U.; Schulz, W.D. [Institut fuer Korrosionsschutz Dresden GmbH, Gostritzer Str. 61-63, D-01217 Dresden (Germany)

    2004-02-01

    The efficiency of prevailing acid inhibitors is examined by age hardening heavy tank-steel plates in technically usual hot-galvanizing solutions for 1000 hours. With acid inhibitors local corrosion emerged as shallow pit formation first and foremost in hydrochlorid acid pickles (20 g/l HCl) at ambient temperature as well as in cleaners containing hydrochloric acid (10-30 g/l HCl) at 40 C when other conditions also applied. Above all, local corrosion was produced if the inhibitor concentration became too low (0.2 g/l) in connection with a minimum hydrochloric acid concentration (10-30 g/l). However, oxidizing agents like iron(III)-ions (5-10 g/l), atmospheric oxygen and free chlorine (100-1000 mg/l) lead to local corrosion, too. Local corrosion did not emerge in rinse baths (2-10 g/l HCl) and fluxing material solutions of zinc chloride and ammonium chloride (pH value: 2.0-5.5). Here uniform corrosion developed. Acid inhibitors turned out to be very effective against uniform corrosion in the examined long-time period (inhibiting values up to 99%). (Abstract Copyright [2004], Wiley Periodicals, Inc.) [German] Die Wirksamkeit handelsueblicher Saeureinhibitoren wird durch eine Auslagerung von Grobblechen aus Behaelterstahl ueber 1000 Stunden in technisch gebraeuchlichen Loesungen der Feuerverzinkung untersucht. Oertliche Korrosion ist als Muldenkorrosion in Gegenwart von Saeureinhibitoren vor allem in Salzsaeurebeizen (20 g/l HCl) bei Raumtemperatur und in salzsaeurehaltigen Reinigern (10-30 g/l HCl) bei 40 C aufgetreten, wenn Zusatzbedingungen erfuellt sind. Oertliche Korrosion wird vorwiegend durch eine Unterschreitung der Inhibitorkonzentration (0,2 g/l) in Verbindung mit einer minimalen Salzsaeurekonzentration (10-30 g/l) ausgeloest. Aber auch Oxidationsmittel wie Eisen(III)-Ionen (5-10 g/l), Luftsauerstoff und freies Chlor (100-1000 mg/l) fuehren zu oertlicher Korrosion. In Spuelbaedern (2-10 g/l HCl) und Flussmittelloesungen aus Zinkchlorid und Ammoniumchlorid (p

  7. Pyritoxidationsprozesse im cretazischen Emschermergel infolge von aeroben Bedingungen durch den Emscherumbau

    Science.gov (United States)

    Droste, Björn; Wisotzky, Frank

    2015-09-01

    Due to the restoration of the Emscher river system, large amounts of the Emschermergel, a Cretaceous sediment containing significant amounts of carbonate and pyrite, will be released from its anoxic state. The oxidation of pyrite results in the release of protons, iron and sulfate. In order to evaluate the impact of the reaction products, extensive laboratory investigations were carried out. The methodology can detect pyrite content in the range of magnitude of the Rhenish lignite mining area (average 0.21 wt.% Pyritic-S). The formation of a naturally-occurring weathering horizon could also be detected. Under laboratory conditions, further oxidation of the weathered laboratory samples could be observed. Column experiments show significant release of sulfate at high concentrations. Hydrochemical modelling and acid-base accounting show neutralization of the free protons by the effective carbonate buffer in the sediment.

  8. Decontamination of nuclear graphite by thermal processing; Dekontamination von Nukleargraphit durch thermische Behandlung

    Energy Technology Data Exchange (ETDEWEB)

    Florjan, Monika W.

    2010-04-15

    The main problem in view of the direct disposal of the nuclear graphite is its large volume. This waste contains long-lived and short-lived radionuclides which determine the waste strategy. The irradiated graphite possess high amount of the {sup 14}C isotope. The main object of the present work was the selective separation of {sup 14}C isotope from the isotope {sup 12}C by thermal treatment (pyrolysis, partial oxidation). A successful separation could reduce the radiotoxicity and offer a different disposal strategy. Three different graphite types were investigated. The samples originate from the reflector and from the flaking of spherical fuel elements of the high-temperature reactor (AVR) Juelich. The samples from the thermal column of the research reactor (Merlin, Juelich) were also investigated. The maximum tritium releases were obtained both in inert gas atmosphere (N{sub 2}) and under water vapour-oxidizing conditions at 1280 C and 900 C. Furthermore it could be shown that 28% of {sup 14}C could be released under inert gas conditions at a 1280 C. By additive of oxidizing agent such as water vapour and oxygen the {sup 14}C release could be increased. Under water vapour-oxidizing conditions at a temperature of 1280 C up to 93% of the {sup 14}C was separated from the graphite. The matrix corrosion of 5.4% was obtained. The selective separation of the {sup 14}C is possible, because a substantial part of the radiocarbon is bound near the grain boundary surfaces. (orig.)

  9. [Peter von Brackel. Christlich Gesprech von der grawsamen Zerstörung in Lifland durch den Muscowiter vom 58. Jar her geschehenn...] / Stefan Donecker

    Index Scriptorium Estoniae

    Donecker, Stefan, 1977-

    2015-01-01

    Arvustus: Christlich Gesprech von der grawsamen Zerstörung in Lifland durch den Muscowiter vom 58. Jar her geschehenn: auch ihren Ursachen mit einer kurtzen Predig und Vermanung, wie beid, Gotlosenn unnd Frommen, diese schreckliche Mutation fruchtbarlich behertzigen und ihnen zu Nutz machen sollen: durch Timannum Brakel Livoniensem, der Gemeine Christi vonn der Augsburgischen Confession Prediger zu Anttorf einfeltig gestellet unnd inn Druck verfertiget = Darstellung der Geschichte Livlands vor und während des "Livländischen Krieges" bis 1578 in gereimter Dialogform und Prosa von dem Prediger und Geschichtsschreiber Timann Brakel : Originaltext und Übersetzung ins Hochdeutsche mit Kommentaren, Ergänzungen, Bildern und dem Lebenslauf des Timann Brakel. (Beiträge zur baltischen Geschichte, 19). Verlag Harro von Hirschheydt. Wedemark 2012

  10. Regenerierung fester Katalysatoren für die Isobutan-Buten-Alkylierung durch hydrierende Behandlung in flüssiger Phase

    OpenAIRE

    Klingmann, Raoul

    2005-01-01

    In der vorliegenden Arbeit wurde die Regenerierung fester Katalysatoren für die Isobutan/Buten-Alkylierung durch hydrierende Behandlung in flüssiger Phase untersucht. Als Katalysatoren dienten edelmetallhaltige Zeolithe des Typs La-X (FAU). Die Alkylierungs- und Regenerierungsexperimente wurden in einer Apparatur mit kontinuierlich betriebenem Rührkesselreaktor und Analytikeinheit mit On-line-Probenahmevorrichtung durchgeführt. Zunächst wurde der Aufbau der Koksdeposite in Abhängigkeit von...

  11. Aktive Steuerung des Transmissionsverhaltens stochastischer Störquellen durch flächige Leichtbaustrukturen [Active feedforward control of the transmission of stochastic disturbances through lightweight panel structures

    OpenAIRE

    Misol, Malte

    2014-01-01

    Leichtbaustrukturen weisen eine geringe Schalldämmung bei tiefen Frequenzen auf. Ihr Einsatz bei Gebäuden, Fahr- oder Flugzeugen ist daher mit negativen Auswirkungen auf die Innenraumakustik verbunden. Adaptronische Maßnahmen, wie die aktive Struktur-Akustik-Regelung (ASAC), können passive Maßnahmen der Schalldämmung flankieren oder ersetzen. Gegenstand dieser Arbeit ist die Beeinflussung der Transmission stochastischer Störquellen durch ein- und doppelwandige Leichtbaustruktursysteme mithilf...

  12. THESEUS - achieving maximum possible road transport tanker safety by means of experimental accident simulation; THESEUS - Tankfahrzeuge mit hoechsterreichbarer Sicherheit durch experimentelle Unfallsimulation

    Energy Technology Data Exchange (ETDEWEB)

    Rompe, K.; Heuser, G.

    1996-03-01

    In spring 1990, the Federal German Minister for Education, Science, Research and Technology (BMBF) commissioned the team from the Federal Institute for Materials Research and Testing (BAM), DEKRA, Daimler-Benz, the Federal Road Research Institute (BASt) with the University of Cologne, Ellinghaus and TUeV Rheinland (project leader) to perform the research project `THESEUS` (the acronym THESEUS comes from the German `Tankfahrzeuge mit hoechst erreichbarer Sicherheit durch experimentelle Unfallsimulation`, which translates as `achieving maximum possible road transport tanker safety by means of experimental accident simulation`). Arting from an analysis of road transport tanker accidents, crash tests and overturn tests were performed and supplemented by investigations of road transport tanker components and accompanying complex calculations of the failure processes. Parallel to this, the static side-tilt stability of road transport tankers was determined on a tilting test platform. The causes of and constructive possibilities for avoiding overturning, which is the most common cause of accidents in which hazardous materials escape, wewre analysed in dynamic driving tests with supplementary computer simulation. Various measures for improving the safety of road transport tankers were determined and subjected to a cost-benefit analysis. (orig.) [Deutsch] Das Bundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie hat seit 1990 das Forschungsproject `THESEUS` (Tankfahrzeuge mit hoechst erreichbarer Sicherheit durch experimentelle Unfallsimulation) der Arbeitsgemeinschaft aus TUeV Rheinland (Federfuehrung), Bundesanstalt fuer Materialforschung und -pruefung (BAM), DEKRA, Daimler Benz, Bundesanstalt fuer Strassenwesen (BASt), Universitaet Koeln und Ellinghaus gefoerdert. Ausgehend von der detaillierten Analyse von 231 Tankfahrzeugunfaellen wurden Tankfahrzeug-Crashversuche und Tankfahrzeug-Umsturzversuche durchgefuehrt. Diese Messungen an kompletten Fahrzeugen

  13. Reuse of filter backwash water with a submerged microfiltration membrane system; Wiederverwendung von Filterspuelwaessern durch Mikrofiltration mit getauchten Membranen

    Energy Technology Data Exchange (ETDEWEB)

    Koetzle, T.; Merkl, G.; Wilderer, P. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl und Lab. fuer Wasserguete- und Abfallwirtschaft; Backhaus, J. [Erlanger Stadtwerke AG, Erlangen (Germany); Hagen, K. [VA TECH WABAG GmbH Kulmbach, Kulmbach (Germany)

    2000-12-01

    During the treatment of groundwater by filtration for drinking water purposes, approximately 3% of the treated water volume has to be used as filter backwash water. Until now this backwash water charged with the accumulated filtrate is then redirected into sewers or receiving waters, either directly or after a sedimentation step. With sufficient separation of the filtered substances from backwash water this could again be used for drinking water purposes. This conserves natural groundwater resources and significantly reduces the volume of wastewater discharged. Especially in the face of the increasing shortage of useable groundwater resources in many countries, this will become increasingly important in the future. In our project, supported by 'EU-Life', the Technical University of Munich will examine on a large-scale plant according to the WABAG-SMS-Process, how far cross-flow microfiltration is capable of purifying the backwash waters for drinking water purposes again. The pilot-plant consists of two treatment parts, one charged with backwash water from the iron-, manganese- and arsenic-elimination, the other charged with backwash water from the deacidification. The membrane modules are submerged in closed storage basins for backwash water. Air is supplied under the modules to generate a defined cross-flow. This article discusses the results after one year of operation of the plant. (orig.) [German] Bei der Aufbereitung von Grundwasser durch Filtration in der Trinkwasseraufbereitung muessen etwa 3% der aufbereiteten Wassermenge zur Rueckspuelung der Filter verwendet werden. Bisher werden die hierbei anfallenden und mit den zuvor abfiltrierten Stoffen belasteten Filterspuelwaesser je nach den oertlichen Gegebenheiten unmittelbar oder nach einer Sedimentationsstufe in Vorfluter oder die oeffentliche Sammelkanalisation abgeschlagen. Durch eine hinreichende Trennung der abfiltrierten Stoffe vom Filterspuelwasser koennte dieses wieder der

  14. Replacement of coal-fuelled stoves by modern room heating systems in multistorey dwellings; Abloesung der Kohle-Einzelofenheizung durch moderne Raumheizungssysteme in Mehrgeschossbauten

    Energy Technology Data Exchange (ETDEWEB)

    Lindner, K. [Institut fuer Energetik und Umwelt gGmbH, Leipzig (Germany)

    1997-12-31

    In eastern Germany, approximately one million residential units in multi-storey apartment buildings are still heated with coal-fired stoves. Not all building societies or private house-owners can afford to substitute modern heating systems for individual coal stoves within the foreseeable future. Problems encountered when modernizing heating systems are described. A way of pre-financing modernization is by loans given by the tenants to the building society. The paper deals with individual aspects, such as contract conditions, organization and experience with this model, as well as its advantages for the landlord and tenant. (MSK) [Deutsch] In Ostdeutschland werden noch rund 1 Million Wohnungen in mehrgeschossigen Wohnhaeuern mit Kohle geheizt. Nicht alle Wohnungsgenossenschaften oder privaten Hauseigentuemer sind finanziell in der Lage in absehbarer Zeit die Kohle-Einzelheizung durch moderne Heizungssysteme abzuloesen. Im Folgenden werden die Probleme bei der Heizungsmodernisierung beschrieben. Der Weg Heizungsmodernisierung durch Mieterdarlehen wird in einzelnen Punkten wie Finanzierung durch Mieterdarlehen, deren Organisation und Erfahrungen mit diesem Modell sowie die Vorteile fuer Vermieter und Mieter dargelegt.

  15. Climate protection by reducing the emissions of greenhouse gases in households and the tertiary sector through climate-conscious behaviour. Vol. 1; Klimaschutz durch Minderung von Treibhausgasemissionen im Bereich Haushalte und Kleinverbrauch durch klimagerechtes Verhalten. Bd. 1. Private Haushalte

    Energy Technology Data Exchange (ETDEWEB)

    Brohmann, B; Cames, M

    2000-06-01

    The aim of the project was to identify areas in households and the tertiary sector in which changes in behaviour could result in energy conservation and thus a reduction of greenhouse gas emissions, and to quantify the potentials for 1995, 2005 and 2020. A second focus was on the analysis and evaluation of programmes and instruments to realise the potentials. With literature evaluation, expert interviews, and a household servey potentials and further technical development have been identified. In sum, behavioural measures can contribute to the CO2 reduction by 64 million tons in 1995 in households and 27 in the commercial sector in which the potential decreases to 18 million tons in 2020 due to the autonomous technical development. Adequate promotion programmes can help to realise 20-30% of the potential by 2020. (orig.) [German] Ziel des Vorhabens war, im Sektor private Haushalte und Kleinverbrauch Bereiche zu identifizieren, in denen Verhaltensaenderungen zur Energieeinsparung fuehren koennen, und diese Potenziale fuer 1995, 2005 und 2020 zu quantifizieren. Darauf aufbauend waren Programme und Instrumente zur Umsetzung aufzuzeigen und zu bewerten. Gestuetzt auf Literaturrecherchen und Expertengespraeche wurden Einzelpotenziale, Rahmenbedingungen, Entwicklungstrends in der Technik und im Ausstattungsgrad ermittelt. Insgesamt koennten Verhaltensmassnahmen im Haushaltssektor die CO2-Emissionen im Basisjahr 1995 um 64 Mio, im Kleinverbrauch um 27 Mio t vermindern. Bis 2020 bleibt dieses Potenzial im Haushaltssektor in etwa gleich. Im Kleinverbrauch sinkt es infolge der autonomen Technikentwicklung auf 18 Mio t ab. Durch geeignete Programme koennen bis 2020 etwa 20-30% des Potenzials erreicht werden. (orig.)

  16. Study of the oxidation risks during the sintering of uranium dioxide, and characterization of the excess oxygen; Etude du risque d'oxydation lors du frittage du bioxyde d'uranium et caracterisation de l'oxygene excedentaire

    Energy Technology Data Exchange (ETDEWEB)

    Conte, M; Brandela, M

    1966-05-01

    During sintering in reducing atmospheres, UO{sub 2} pellets can be oxidized by gaseous impurities. The effects of temperature cycles, the partial pressure of O{sub 2} and the flow rate of the gas over the pellets were investigated. In these atmospheres, the O{sub 2} partial pressure during sintering is low at high temperatures, as a consequence of the dissociation rate of the combined water, but below 1000 deg C, it can be high enough to result in a noticeable oxidation of the surface of the pellets during cooling. The crystalline phases which can occur have been identified and two methods of detection have been proposed: a micrographic examination after chemical etching and radiocrystallography. (authors) [French] Lors du frittage industriel du bioxyde d'uranium en atmosphere reductrice (hydrogene ou ammoniac dissocie) la presence d'impuretes oxydantes dans l'atmosphere peut provoquer l'oxydation des pastilles d'UO{sub 2}; les auteurs ont etudie les phenomenes en faisant varier le cycle de temperature, la pression partielle d'oxygene introduit dans l'hydrogene, la vitesse de passage du gaz sur les pastilles. Dans les atmospheres considerees la pression partielle d'oxygene au-dessus de l'UO{sub 2} en cours de frittage est faible a temperature elevee car elle resulte de la dissociation de l'eau formee, mais a t < 1000 degrees C elle, peut etre assez importante pour provoquer une oxydation notable de la surface des pastilles lors du refroidissement. Les phases cristallines susceptibles d'etre formees ont ete reperees et deux methodes de detection proposees: la micrographie apres attaque chimique specifique et la radiocristallographie. (auteurs)

  17. Stabilization of the cleaning of anaerobic waste water with the aid of activated sludge following receipts of hydrogen peroxide; Stabilisierung der anaeroben Abwasserreinigung durch Belebtschlamm nach Eintrag von Wasserstoffperoxid

    Energy Technology Data Exchange (ETDEWEB)

    Stupperich, E. [Ulm Univ. (Germany). Abt. Angewandte Mikrobiologie; Gerstmeir, R. [Ulm Univ. (Germany). Abt. Angewandte Mikrobiologie; Marqua, J. [Ulm Univ. (Germany). Abt. Angewandte Mikrobiologie; Rothfuss, A. [Ulm Univ. (Germany). Abt. Angewandte Mikrobiologie

    1996-12-31

    Some municipal and industrial sewage treatment plants comprise an aerobic and an anaerobic unit. However, discharge conditions may be such as to cause strong oxidants like hydrogen peroxide (H{sub 2}O{sub 2}) to enter the anaerobic unit. As measurements of the reduction-oxidation potential in an acidification stage showed, small concentrations of H{sub 2}O{sub 2}, already, may cause irreversible damage to the anaerobic bacterial strains living there. Adding activated sludge from the aerobic unit to such a system can prevent the damage. Probably, the enzyme catalase protects the anaerobic system against the oxydizing effect of hydrogen peroxide: this enzyme from aerobic bacteria and optionally aerobic bacteria causes the ecologically compatible decomposition of hydrogen peroxide into water and oxygen, which is substantially less reactive. Optionally aerobic bacteria, which are also added, protect the anaerobic system further by consuming this oxygen. (orig.) [Deutsch] Manche kommunalen und industriellen Klaeranlagen bestehen aus einer Aerobie und einer Anaerobie. Verschiedene Einleitungsbedingungen koennen aber dazu fuehren, dass in die Anaerobie starke Oxidationsmittel wie Wasserstoffperoxid (H{sub 2}O{sub 2}) gelangen. Messungen des Redoxpotentials in einer Versaeuerungsstufe zeigen, dass bereits geringe Konzentrationen an H{sub 2}O{sub 2} die dort lebenden anaeroben Bakterienkulturen irreversibel schaedigen. Wird aber einem solchen System Belebtschlamm aus der Aerobie zudosiert, so kann diese Schaedigung verhindert werden. Wahrscheinlich schuetzt das Enzym Katalase die Anaerobie vor der oxidierenden Wirkung des Wasserstoffperoxids. Dieses Enzym aus aeroben und fakultativ aeroben Bakterien zersetzt naemlich Wasserstoffperoxid oekologisch vertraeglich in Wasser und den bedeutend weniger reaktiven Sauerstoff. Zum Schutz der Anaerobie wird auch dieser Sauerstoff durch die zudosierten fakultativ aeroben Bakterien verbraucht. (orig.)

  18. On-line analysis of water contamination by organic compounds; On-line-Analytik der Wasserverschmutzung durch organische Substanzen

    Energy Technology Data Exchange (ETDEWEB)

    Wagt, R. van der; Vos, F. de [Skalar Analytical (Netherlands); Babichenko, S.; Poryvkina, L. [Institute of Ecology, Tallinn (Estonia)

    1999-08-01

    In many environmental applications decomposing the mixture of substances in the water into its various chemical ingredients, for subsequent analysis, is a very complicated task. The most productive approach to on-line diagnosis is to treat the object as an integral spectroscopic sample, characterized by certain specific Spectral Fluorescent Signatures (SFS). The SFS are recorded as a matrix of fluorescent intensity of organic compounds in water, in co-ordinates of excitation and emission spectra, providing a three-dimensional spectrum. Spectral windows of SFS are defined by fluorescent characteristics of basic groups of organic substances in the water sample. The novel Skalar Fluo Imager, based on this principle, is intended for the analysis of organic compounds in natural, domestic, and technological waters in an on-line mode. (orig.) [German] In vielen Umweltschutzanwendungen stellt die Auftrennung eines Substanzgemisches zum Zweck der Analyse eine sehr komplizierte Aufgabe dar. Ein erfolgversprechender Ansatz fuer eine on-line-Diagnostik besteht darin, das Objekt als integrale Spektroskopieprobe zu betrachten, die durch bestimmte spezifische Spektral-Fluoreszenz-Signaturen (SFS) charakterisiert wird. Diese werden als Fluoreszenz-Intensitaets-Matrix organischer Verbindungen in Wasser dargestellt, mit Anregungs- und Emissionsspektren als weiteren Koordinaten, wodurch ein dreidimensionales Spektrum entsteht. Spektrale Fenster der SFS sind definiert als Fluoreszenzcharakteristika von Funktionsgruppen organischer Substanzen in der Wasserprobe. Der auf diesem Prinzip basierende Skalar Fluo Imager ist fuer die on-line-Analyse organischer Bestandteile in natuerlichen, Haus- und technischen Waessern gedacht. (orig.)

  19. Neue Möglichkeiten in der archäologischen arbeit durch den Einsatz digitales Bildauswertung und photogrammetrischer Messtechniken

    Directory of Open Access Journals (Sweden)

    Jan Wesbuer

    2005-01-01

    Full Text Available Die digitale Bildbearbeitung und die digitale Photogrammetrie haben in den letzten Jahren, neben vielen anderen Gebieten, die Dokumentation von Ausgrabungsstätten beeinflusst. Die Photogrammetrie hat ihren Ursprung in der Vermessungskunde. Sie wird heutzutage in vielen Bereichen der Ingenieurwissenschaften eingesetzt und hat somit viele Schnittbereiche zu angrenzenden wissenschaftlichen Gebieten. In der Archäologie hat sie daher die Möglichkeit, in vielen Bereichen die herkömmliche Geodäsie zu erweitern bzw. neue Möglichkeiten der Visualisierung zu schaffen oder bei der Bildauswertung zu helfen.Durch die Bildbearbeitung ist es heutzutage möglich, schnell und vor Ort die Dokumentation vorzunehmen. Mit ihrer Hilfe können z.B. nicht orthogonale Aufnahmen perspektivisch entzerrt werden, so dass in ihnen wieder gemessen werden kann.Der Artikel unterteilt sich in 3 Bereiche:• als erstes werden die Möglichkeiten der digitalen Bildbearbeitung bzw. Auswertung von Photos dargestellt.• danach wird auf die photogrammetrische Auswertung und Vermessung von Ausgrabungsstätten eingegangen. • und zuletzt werden einige Visualisierungsmöglichkeiten gezeigt, die mit Hilfe der photogrammetrischen Auswertung und 3DModellerstellung realisiert werden können.

  20. Advantages of variable-speed operation of hydraulic turbo-engines; Vorteile durch den drehzahlvariablen Betrieb von hydraulischen Stroemungsmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Harbort, T. [Stuttgart Univ. (Germany). Inst. fuer Stroemungsmechanik und Hydraulische Stroemungsmaschinen

    1997-12-31

    The performance of current hydraulic turbo-engines in the variable speed sector is monitored and judged. The study covers radial and axial engines as well as Pelton turbines. Variable-speed operation of hydraulic turbo-engines can be realized by means of different combinations of electrical rotating machines and frequency converters. The operating range of the frequency converter plays an important role in the optimization of performance and is taken into account. The smoothness of run of reaction turbines and their cavitation performance can be enhanced by speed regulation. But above all, efficiency is more or less substantially enhanced during partial load or in the case of greatly varying heights of drop. The latter holds true also of Pelton turbines. (orig.) [Deutsch] Das Betriebsverhalten der gaengigen hydraulischen Stroemungsmaschinen wird in Hinblick auf den drehzahlvariablen Betrieb erfasst und beurteilt. Die Untersuchung erfolgt fuer Radialmaschinen, Axialmaschinen und Peltonturbinen. Der drehzahlvariable Betrieb hydraulischer Stroemungsmaschinen kann mit verschiedenen Kombinationen von elektrischen Maschinen und Frequenzumrichtern realisiert werden. Der Arbeitsbereich des Frequenzumrichters spielt eine wichtige Rolle fuer die Optimierung des Betriebsverhaltens und wird beruecksichtigt. Bei Ueberdruckturbinen kann man durch Drehzahlregelung eine groessere Laufruhe sowie ein guenstigeres Kavitationsverhalten erreichen. Vor allem aber sind im Teillastbereich oder bei stark schwankenden Fallhoehen mehr oder weniger grosse Wirkungsgradgewinne erzielbar. Das letztere gilt auch fuer Peltonturbinen. (orig.)

  1. Altitude dependence of trace substance deposition from clouds to forests. Final report; Hoehenabhaengigkeit der Spurenstoffdeposition durch Wolken auf Waelder. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Pahl, S.; Winkler, P.

    1995-12-31

    Novel forest decline is particularly pronounced in the area of the ridges of medium-range mountains. Whereas acid precipitation was viewed as its sole cause early on in the discussions, it turned out later that the impact of trace gases, too, contributes to the damaging of forests. This report wants to point out the importance of fog interception, which equally plays a part in the pollutant receipts of forests. The deposition of fog water to a forest stand depends very much on altitude, so that trace substance deposition, too, is to be expected to be dependent on altitude. By attempting to quantify this effect, the report helps to pinpoint areas of relevance of this deposition pathway (orig./KW) [Deutsch] Die neuartigen Waldschaeden sind in den Kammlagen der Mittelgebirge besonders ausgepraegt. Waehrend in der anfaenglichen Diskussion die sauren Niederschlaege als alleinige Ursache angesehen wurden, zeigte sich spaeter, dass auch Einwirkungen von Spurengasen zur Schaedigung des Waldes beitragen. Dieser Bericht soll auf die Bedeutung der Nebelinterzeption aufmerksam machen, die ebenfalls zum Schadstoffeintrag in den Wald beitraegt. Die Deposition von Wolkenwasser auf einen Waldbestand ist stark abhaengig von der Hoehenlage, in der sich der Waldbestand befindet, so dass auch eine Hoehenabhaengigkeit des Spurenstoffeintrages zu erwarten ist. Durch den Versuch der Quantifizierung traegt dieser Bericht dazu bei, Gebiete zu erkennen, in denen dieser Eintragspfad eine Rolle spielt. (orig./KW)

  2. Retrospektive Analyse von Zufallsbefunden, die bei Patienten mit kutanem malignen Malignom durch (18) F-Fluordeoxyglucose-PET/CT erhoben wurden.

    Science.gov (United States)

    Conrad, Franziska; Winkens, Thomas; Kaatz, Martin; Goetze, Steven; Freesmeyer, Martin

    2016-08-01

    Bei der (18) F-Fluordeoxyglucose-Positronenemissionstomographie/Computertomographie (FDG-PET/CT) ergeben sich häufig Zufallsbefunde. In der vorliegenden Studie konzentrierten wir uns auf mittels FDG-PET/CT erhaltene Zufallsbefunde bei Patienten mit kutanem Melanom und überprüften deren Relevanz hinsichtlich weiterer diagnostischer Maßnahmen und Interventionen. Die Krankenakten von 181 konsekutiven Melanom-Patienten wurden retrospektiv ausgewertet, um das Management von Zufallsbefunden zu dokumentieren. Der Schwerpunkt lag dabei auf den histologischen Befunden. Bei 33 von 181 (18 %) Patienten lagen 39 relevante Zufallsbefunde vor, und zwar im Kolorektalbereich (n = 15 Patienten), in der Schilddrüse (n = 8), der Prostata (n = 2), dem Bewegungsapparat (n = 2), in Lymphknoten (n = 2), der Parotis (n = 1), den Mandeln (n = 1), den Nieren (n = 1) und der Gallenblase (n = 1). Bei 25 Patienten schlossen sich weitere diagnostische Verfahren an, wobei in 21 Fällen ein klinisches Korrelat nachgewiesen wurde. Bei 16 von 21 Patienten ergab sich eine Neoplasie, darunter fünf maligne Läsionen (vier Kolonkarzinome und ein Prostatakarzinom). Die Malignome wurden frühzeitig diagnostiziert und in der Mehrzahl der Fälle erfolgreich entfernt. Der Einsatz der FDG-PET/CT als Routine-Diagnostik wird in den Leitlinien empfohlen und ist indiziert bei malignem Melanom ab Stadium IIC. In dieser Studie wurden auf effektive Weise ansonsten nicht erkannte Krebserkrankungen, insbesondere Kolonkarzinome, detektiert. In den meisten Fällen war eine frühe Intervention möglich. Zufallsbefunde durch FDG-PET/CT sollten, unter Berücksichtigung des Zustands und der Wünsche des Patienten, mit den geeigneten diagnostischen Maßnahmen abgeklärt werden. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  3. Potential and possibilities of supplying energy from biomass and biogas; Potentiale und Moeglichkeiten der Energiebereitstellung durch Biomasse und Biogas

    Energy Technology Data Exchange (ETDEWEB)

    Sonnenberg, H. [Bundesforschungsanstalt fuer Landwirtschaft, Braunschweig (Germany). Inst. fuer Betriebstechnik; Weiland, P.; Ahlgrimm, H.J. [Bundesforschungsanstalt fuer Landwirtschaft (FAL), Braunschweig (Germany). Inst. fuer Technologie

    1998-06-01

    Agriculture`s potential contribution to the energy supply of the ``town of the future`` through the conversion of biomass to energy, including biogas production, is a rather modest one. Supposing that the share of total renewable energy in Germany`s primary energy demand rises to approximately 4%, then the proportion of biomass from biotic raw materials especially produced for the purpose will at the most make up an eighth of this amount. Beyond this, biomass is burdened with other drawbacks such as low supply efficiency, limited availability, and weather-dependent reliability. On the other hand, biomass is well suited for conversion to solid, liquid, and gaseous fuels, including inexpensive ones with low energy density (solid fuels), mostly used for stationary heating applications, as well as more expensive ones such as liquid fuels with a high energy density for mobile applications in the automotive sector. Thanks to its capacity to regenerate, biomass is an inexhaustible resource. Moreover, its natural life cycle has a small impact on the environment. [Deutsch] Der Beitrag, den die Landwirtschaft durch energetische Nutzung von Biomasse, z.B. auch mit der Erzeugung von Biogas, zur Energieversorgung der `Stadt der Zukunft` leisten kann, nimmt sich bescheiden aus. Wird erwartet, dass innerhalb des naechsten Jahrzehnts der Anteil regenerativer Energien insgesamt auf etwa 4% des Primaerenergie-Verbrauchs Deutschlands ansteigen koennte, so duerfte Biomasse als speziell zur Energiegewinnung angebaute nachwachsende Rohstoffe mit bestensfalls 0,5 Prozentpunkten daran beteiligt sein. Es beduerfen darueber hinaus auch Nachteile, wie geringe Bereitstellungseffizienz, beschraenkte Verfuegbarkeit und witterungsabhaengige Zuverlaessigkeit, der Beachtung. Die Biomasse kann jedoch mit Erfolg in feste, fluessige und gasfoermige Energietraeger konvertiert werden, sowohl in preiswerte mit geringer Energiedichte (Festbrennstoffe) fuer bevorzugt stationaeren Heizungs-Einsatz als auch

  4. Higher efficiency of steam flooding projects with horizontal production wells; Verbesserung der Effizienz von Dampfflutprojekten durch horizontale Foerderbohrungen

    Energy Technology Data Exchange (ETDEWEB)

    Leonhardt, B. [Wintershall AG Erdoelwerke, Barnstorf (Germany)

    2001-07-01

    For 50 years, the Emlichheim oil field has had a production level of about 150,000 t.p.a. of crude oil. Reinjection of deposit water was started in 1952 already in order to maintain the required pressure. Until 1997, all wells were sunk vertically as the loose sandstone was considered unstable. The Emlichheim 300 well was constructed in 1999; it was the first horizontal well that proved that horizontal drilling is possible in this bedrock material. The contribution describes the history of this field and the projecting and implementation of a steam flooding project involving horizontal production wells. [German] Das Erdoelfeld Emlichheim weist seit nunmehr 50 Jahren ein Foerderplateau von rund 150.000 Jahrestonnen Reinoel auf. Nach der Produktionsaufnahme in 1944 wurde dieses Niveau erstmals 1950 erreicht. Bereits 1952 musste zur Druckerhaltung mit der Reinjektion von Lagerstaettenwasser begonnen werden. Bis 1997 wurden alle Bohrungen im Erdoelfeld Emlichheim vertikal abgeteuft. Als groesstes Problem fuer Horizontalbohrungen wurde die Bohrlochstabilitaet in der Bohr- und Komplettierungsphase erachtet, da der Bentheimer Sandstein unverfestigt ist. Mit dem Abteufen der Emlichheim 300 im Jahre 1999 wurde der Nachweis erbracht, dass das Bohren und Komplettieren einer ca. 280 m langen Horizontalstrecke in diesem Traeger erfolgreich moeglich ist. Vorliegende Publikation gibt einen kurzen Einblick in die Geschichte des Feldes, die Planung und Realisierung eines laufenden Dampfflutprojektes unter Einbindung von horizontalen Foerderbohrungen und vergleicht deren Performance mit frueheren Projekten. Zusaetzlich wird auf gewonnene Erkenntnisse durch das Abteufen von Horizontalbohrungen im nicht verfestigten Sandstein eingegangen. Abschliessend soll ein Ausblick auf die weitere Feldentwicklung gegeben werden. (orig.)

  5. Detection of partial discharges in oil transformers with the aid of acoustic emission analysis; Detektion von Teilentladungen in Oeltransformatoren durch die Schallemissionsanalyse

    Energy Technology Data Exchange (ETDEWEB)

    Loehr, M. [Physical Acoustics BV - Deutschland, Hamburg (Germany)

    2007-07-01

    Since the early eighties, acoustic emission analysis has been used for functional testing of transformers. Partial discharges of 150 pC and above are detected reliably. Transformers with oil/paper insulation as a rule are inspected during operation by analysis of the transformer oil at regular intervals or continuously. This integral method provides no information on the operating conditions causing partial discharge and no information on their location. This information gap may be closed by acoustic emission analysis, which will provide the key information required for selective planning of preventive measures. Physical Acoustics (PAC) tested several hundreds of transformers successfully for their operating performance (see also EPRI Project I.D. No. 051481). As a result, e.g., transformers can now be operated for a longer period of time below critical load. [German] Die Schallemissionsanalyse wird seit den fruehen 80-iger Jahren letzten Jahrhunderts von Transformator-Herstellern bei der Funktionspruefung eingesetzt. Hierbei werden Teilentladungen von 150 pC und mehr zuverlaessig detektiert. Oel-papierisolierte Transformatoren werden in der Regel waehrend des Betriebs durch eine Analyse des Transformator-Oels inspeziert. Die Oelanalyse kann in regelmaessigen Abstaenden oder dauerhaft erfolgen. Als integrales Verfahren bietet diese Methode keine Information zu den Betriebsbedingungen unter den Teilentladungen auftreten und gibt auch keine Information zum Ort deren Auftretens. Diese Informationsluecke kann durch den Einsatz einer Schallemissionspruefung (AT) geschlossen werden. Mit dem Messen der Schallemission durch am Trafokessel angebrachte Sensoren kann der Ort und der Zeitpunkt von Stoerungen festgestellt werden. Mit diesen Schluesselinformationen wird es moeglich, die weiteren notwendigen Massnahmen gezielt zu planen. Physical Acoustics (PAC) hat mehrere hunderte von Transformatoren erfolgreich auf ihr Betriebsverhalten untersucht (siehe auch EPRI-Projekt I

  6. Wir überwachen uns. Wie die Sicherheit durch die Digitalisierung immer tiefer in den Alltag eingreift und warum uns das nicht interessiert

    Directory of Open Access Journals (Sweden)

    Martin Schinagl

    2014-10-01

    Full Text Available Der Bereich der Überwachung und Sicherheit unterliegt einer neoliberalen Neuausrichtung. Mit der Entstehung unheiliger Allianzen zwischen Staat und Wirtschaft, gezielter Privatisierung und einer neuen Warenförmigkeit von Sicherheit entgrenzen sich zunehmend auch deren Produktionsprozesse. Das Subjekt wird durch eine Digitalisierung der Alltagswelten zunehmend in die Sicherheitsarbeit mit eingebunden und übernimmt zentrale Aufgaben. Der Mensch, ohne dessen Zutun das digitale Überwachungssystem nicht so gut funktionieren würde, erscheint außerstande und unwillig, sich dieser Entwicklung zu entziehen.

  7. Attenuation corrections through energy spectra analysis of whole body and partial body measurements applying gamma spectroscopy; Schwaechungskorrektur bei gammaspektroskopischen Ganz- und Teilkoerpermessungen durch Analyse der Energiespektren

    Energy Technology Data Exchange (ETDEWEB)

    Schelper, L.F.; Lassmann, M.; Haenscheid, H.; Reiners, C. [Wuerzburg Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    1997-12-01

    The study was carried out within the framework of activities for testing means of direct determination of radioactivity levels in the human body due to incorporated, inhomogenously distributed radionuclides. A major task was to derive the average depth of activity distributions, particularly from photon radiation at energies below 500 keV, for the purpose of making suitable attenuation corrections. The paper presents two applicable methods which yield information on the mean depths of activity distributions, obtained through additional analyses of the energy spectra. The analyses are based on measuring the dependence of intensity of the Compton radiation on the length of pathways of the photons penetrating the soft tissue, or on measuring the energy-dependent absorption effects with photons. (orig./CB) [Deutsch] Im Rahmen der direkten Aktivitaetsbestimmung bei inhomogener Radionukliddeposition im menschlichen Koerper mittels Ganz- oder Teilkoerpermessanlagen im klinischen Bereich oder im Strahlenschutz sollte besonders bei Photonenstrahlung mit Energien von weniger als 500 keV eine Ermittlung der mittleren Tiefe der Aktivitaetsverteilung zur Schwaechungskorrektur erfolgen. Im klinischen Umfeld ist es haeufig moeglich, zur Tiefenkorrektur die mittlere Organtiefe und damit die schwaechende Gewebsschicht mittels Ultraschall zu bestimmen. Ergaenzend hierzu werden im Folgenden zwei Methoden vorgestellt, welche Aussagen ueber die mittlere Tiefe von Aktivitaetsverteilungen durch Gewinnung von Zusatzinformationen aus dem Energiespektrum im Rahmen von gamma-spektroskopischen Personenmessungen ermoeglichen. Dazu werden einerseits die Abhaengigkeit der Intensitaet der Comptonstrahlung von der Laenge der Wegstrecke von Photonen durch Weichgewebe und andererseits energieabhaengige Absorptionseffekte bei Photonen als Grundlage herangezogen. (orig.)

  8. Fetal lung development on MRI. Normal course and impairment due to premature rupture of membranes; Fetale Lungenentwicklung in der MRT. Normaler Verlauf und Beeintraechtigung durch vorzeitigen Blasensprung

    Energy Technology Data Exchange (ETDEWEB)

    Kasprian, G. [Medizinische Universitaet Wien (Austria). Klinik fuer Radiodiagnostik; Zentrum fuer Anatomie und Zellbiologie der Medizinischen Universitaet Wien (Austria). Arbeitsgruppe Integrative Morphologie; Brugger, P.C. [Zentrum fuer Anatomie und Zellbiologie der Medizinischen Universitaet Wien (Austria). Arbeitsgruppe Integrative Morphologie; Helmer, H.; Langer, M. [Medizinische Universitaet Wien (Austria). Klinik fuer Frauenheilkunde; Balassy, C.; Prayer, D. [Medizinische Universitaet Wien (Austria). Klinik fuer Radiodiagnostik

    2006-02-15

    A well-organized interplay between many molecular factors as well as mechanical forces influence fetal lung development. At the end of this complex process a sufficiently sized and structurally mature organ should ensure the postnatal survival of the newborn. Besides prenatal ultrasonography, magnetic resonance imaging (MRI) can now be used to investigate normal and pathological human lung growth in utero. Oligohydramnios, due to premature rupture of membranes (PROM), is an important risk factor for compromised fetal lung growth. In these situations MR volumetry can be used to measure the size of the fetal lung quite accurately. Together with the evaluation of lung signal intensities on T2-weighted sequences, fetuses with pulmonary hypoplasia can be readily detected. (orig.) [German] Die fetale Lungenentwicklung wird einerseits durch eine Vielzahl molekularer Faktoren und andererseits durch mechanisch-physiologische Kraefte beeinflusst. Ein geordnetes Zusammenspiel dieser Mechanismen fuehrt zu einem ausreichend grossen und strukturell reifen Organ, das sofort nach der Geburt das Ueberleben des Neugeborenen sicherstellt. Neben der praenatalen Ultraschalluntersuchung bietet nun auch die Magnetresonanztomographie (MRT) die Moeglichkeit, die normale und pathologische fetale Lungenentwicklung zu untersuchen. Ein wesentlicher Risikofaktor fuer eine Beeintraechtigung der Lungenentwicklung ist die verminderte Fruchtwassermenge nach vorzeitigem Blasensprung. In diesen Faellen kann die MR-Volumetrie dazu eingesetzt werden, die Groesse der fetalen Lungen relativ genau zu bestimmen. Gemeinsam mit der Beurteilung der MR-Signalintensitaeten des Lungengewebes auf T2-gewichteten Sequenzen koennen Feten mit hypoplastischen Lungen mit zunehmender Sicherheit bereits praenatal identifiziert werden. (orig.)

  9. Mobilization of PAH by synthetic gastrointestinal juice from contaminated soil of a former landfill area; Mobilisierung von PAK durch synthetische Verdauungssaefte aus dem kontaminierten Bodenmaterial einer Altlastenflaeche

    Energy Technology Data Exchange (ETDEWEB)

    Hack, A.; Selenka, F.; Wilhelm, M. [Bochum Univ. (Germany). Abt. fuer Hygiene, Sozial- und Umweltmedizin

    1998-10-01

    In the present study, the amount of polycyclic aromatic hydrocarbons (PAH) in contaminated soil material, which may be available for absorption in the gastrointestinal tract, is estimated by means of evaluating the PAH mobilization by synthetic gastric and intestinal juice in an in vitro test system. Five contaminated soil materials from a former landfill site are analysed in this gastrointestinal model for the PAH of the U.S.EPA-standard. For quantification, an HPLC method with reversed-phase chromatography and on line fluorescence detection is used. The PAH concentration of the contaminated soil materials ranged from 37 {mu}g/g up to 196 {mu}g/g in total. The mobilization of the PAH in the gastrointestinal model ranged from 0.3% up to 1.3% when gastrointestinal juice was used alone. In the presence of whole milk powder, however, the mobilization was enhanced to values from 10.8% up to 14.5%. Since the soil material was taken from different parts of the contaminated area, and since the mobilization of the PAH from the different materials shows only minor differences, the mobilization data evaluated may be considered as representative for the whole contaminated area. Compared to other contaminated soil materials, especially those from gas work areas or coke plants, the mobilization rate of PAH by the gastrointestinal model from the soil materials used in this study is low. The health risk caused, by ingestion of this soil material, as far as PAH are concerned, is actually smaller than the risk calculated from the total content of PAH of the contaminated soil. (orig.) [Deutsch] Im allgemeinen wird nur ein Teil der Schadstoffe aus oral aufgenommenem kontaminiertem Bodenmaterial im Gastrointestinaltrakt resorbiert. In der vorliegenden Studie wird der resorptionsverfuegbare Anteil der PAK aus dem real kontaminierten Bodenmaterial einer ehemaligen Deponie aus dem sueddeutschen Raum anhand der Mobilisierbarkeit der PAK durch die Verdauungssaefte des oberen

  10. Durch Zwang zur Freiheit?

    Directory of Open Access Journals (Sweden)

    Peter Collin

    2011-01-01

    Full Text Available Economic self-government occurs when organized economic actors fulfill public duties, participate in providing law and law enforcement, and are given scope for the exercise of their interests. It takes place in advisory boards, chambers and cooperatives regulated by public law. Economic self-government emerged in the 19th century. Its importance increased primarily from the end of the 19th century, the time of the emergence of the interventionist state. This development seemed to be accompanied by a loss of freedom because self-government was legally constructed as a state-dependent form of organization. Above all, it was subject to state supervision. However, this review would be one-sided. The establishment of self-government, simultaneously, created the possibility of increased influence on public affairs. The semi-official character of self-government institutions strengthened the legitimacy of the economic representation of interests and the power of enforcement in relation to government authorities and other organized societal actors. Economic self-government was a way of coordinating divergent interests more effectively in a highly differentiated society and enlarging the space for the collective exercise of freedom. The resulting increased dependence on the state was a price which large parts of society were willing to pay.

  11. Hautreizungen durch Propylenglykol

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Storrs, F J

    1982-01-01

    Propylene glycol is used in foods, medicine and cosmetics because it is a good solvent which has, simultaneously, moisture-regulating, antiseptic, and preservative effects. Propylene glycol may produce eczematous skin reactions of toxic and, more rarely, of allergic nature. Positive patch test...... by dermatologists as propylene glycol is used in local steroids and other topical preparations....

  12. Properties of polymer-silver nanocomposites fabricated by co-sputtering; Eigenschaften von Polymer-Silber-Nanokompositen hergestellt durch Co-Sputtern

    Energy Technology Data Exchange (ETDEWEB)

    Schuermann, Ulrich

    2006-07-01

    In this thesis polymer-metal nanocomposites were fabricated by simultaneous sputtering of silver and polymers from two independent magnetron sputtering sources. By the netted structure and the dielectric properties PTFE is suited for the use as matrix material. The metal content of the composite films was determined via the measurement of EDX intensities. The size of the nanoparticles was determined by means of TEM and XRD and lies in the range of 10 nm. The composite materials show at the percolation limit a sudden transition of the properties from polymer- to metal-like behaviour. The specific resistance decreases in a range between 35 and 40 % silver content by at least nine orders of magnitude. The optical properties change with the metal content. The absorption caused by plasmon resonance, which has at small filling degrees its maximum at about 000 nm and has an intense yellow colour of the composite material as consequence shifts with increasing silver content to longer wavelengths. The difference in the optical.behaviour of the nanocomposites and the pure polymers can be used for the fabrication of Bragg reflectors. Small changes in the metal content can in the polymer-silver nanocomposites in the range of the percolation threshold effect a drastic change in ther properties, by which applications as sensors are thinkable. [German] In dieser Arbeit wurden Polymer-Metall-Nanokomposite durch gleichzeitiges Sputtern von Silber und Polymeren aus zwei unabhaengigen Magnetron-Sputterquellen hergestellt. Durch die vernetzte Struktur und die dielektrischen Eigenschaften eignet sich PTFE zur Verwendung als Matrixmaterial. Der Metallgehalt der Kompositfilme wurde ueber die Messung von EDX-Intensitaeten ermittelt. Die Groesse der Nanopartikel wurde mit Hilfe von TEM und XRD bestimmt und liegt im Bereich von 10 nm. Die Kompositmaterialien zeigen an der Perkolationsgrenze einen schlagartigen Uebergang der Eigenschaften vom polymer- zum metallaehnlichen Verhalten. Der

  13. BioCrack {sup registered}. Enhanced gas yield by electrokinetic disintegration; BioCrack {sup registered}. Steigerung der Gasausbeute durch elektrokinetische Desintegration

    Energy Technology Data Exchange (ETDEWEB)

    Liebich, Markus [Hugo Vogelsang Maschinenbau GmbH (Germany)

    2011-07-01

    In the electrokinetic disintegration process, the fluid flows through a pipeline system to which a HV field is applied. The electric forces of the HV field deform and destabilise the cell membrane. Once the deformation exceeds the elastic resistance of the cell membrane, the cell membrane will become permeable, and the cell content will be released and can be used for gas production. The advantages of theprocess are the low investment cost, simple retrofitting, high availability, and low energy cost (35 W per module). [German] Bei der elektrokinetischen Desintegration durchfliesst das Medium ein Rohrleitungssystem in dem ein Hochspannungsfeld anliegt. Durch die auftretenden elektrischen Kraefte im Hochspannungsfeld wird die Zellmembran verformt und destabilisiert. Uebersteigt die Verformung die elastische Widerstandkraft der Zellmembran, so wird diese durchlaessig. Dadurch werden die Zellinhaltsstoffe freigesetzt und koennen zur Gaserzeugung genutzt werden. Die Vorteile dieses Verfahrens liegen in den geringen Investitionskosten gegenueber anderen Desintegrationsverfahren, der einfachen Nachruestbarkeit, der hoher Anlagenverfuegbarkeit sowie in den geringen Energiekosten (35 W pro Modul).

  14. A practical example of how companies can cut down their costs by means of an environmental management system; Moeglichkeit der Kostensenkung in Betrieben durch Umweltmanagement am praktischen Beispiel

    Energy Technology Data Exchange (ETDEWEB)

    Grooterhorst, A. [SIG Consult GmbH, Essen (Germany)

    1997-01-01

    Regular acquisition of environmentally relevant data permits systematic monitoring of the environmental impact of industrial operations. This, together with a systematic documentation and the efficient organization of operations, creates the basis for an environmental management system. When designing an environmental protection concept or introducing an environmental management system, it may be convenient to make use of the services of consultancies. (orig./ABI) [Deutsch] Durch regelmaessige Erfassung umweltrelevanter Daten wird eine systematische Kontrolle betrieblicher Umweltauswirkungen moeglich. Zusammen mit einer systematischen Dokumentation und einer nachweislichen Regelung zur Aufbau- und Ablauforganisation ist damit die Grundlage fuer ein Umweltmanagementsystem geschaffen. Bei der Erarbeitung eines Umweltschutzkonzeptes und der Einfuehrung eines Umweltmanagementsystems kann es sinnvoll sein einen externen Berater einzuschalten. (orig./ABI)

  15. Revolution by way of technical transfer in the development of locomotive brake systems; Revolutionierung in der Entwicklung von Bremssystemen bei Lokomotiven durch Technologietransfer

    Energy Technology Data Exchange (ETDEWEB)

    Wright, E.C. [New York Air Brake (United States). Bereich Engineering; Sinn, R. [New York Air Brake (United States). Bereich Elektronik und Software

    1997-12-31

    With the use of components from other sectors and orientation on the technologies of other fields it has been possible to enhance the standard of electronic braking systems. The reliability of the CCBII is ten times greater than with conventional systems. The physical volume could be reduced by 40 percent and the weight by 30 percent. The CCBII has functional redundancy and the Locotrol Distributed Power System is already integrated. A diagnostics system allows repair times to be reduced to 20 minutes. Production is now commencing and it is planned to make the first deliveries starting from January 1998. (orig.) [Deutsch] Durch das Einbinden von Entwurfsverfahren aus der Luft- und Raumfahrtindustrie sowie der Verwendung von Komponenten aus dem Automobilsektor, hochentwickelter Werkstoffe und Techniken ist es moeglich, neue Wege bei Bremssystemen zu gehen. Der Beitrag beschreibt die Entwicklung einer neuen Generation von computergesteuerten Bremssystemen fuer Lokomotiven. (orig.)

  16. Efficient turbine control. Advantages through controlling internal turbine power in place of turbo generator output; Effektive Turbinenregelung. Vorteile durch die Regelung der inneren Turbinenleistung anstelle der Turbogeneratorleistung

    Energy Technology Data Exchange (ETDEWEB)

    Sindelar, R.

    1999-07-01

    Hitherto, the electrical output of turbo generators has generally been controlled by means of power output controllers. Load changes caused, for example, by changeovers to isolated unit operation where the load requirements are unknown at first, often resulted in `wrong way control` effects that sometimes even caused entire turbine generator sets to fail. Controlling the internal turbine power makes it possible to avoid such consequences. (orig.) [Deutsch] Die elektrische Leistung eines Turbogenerators wurde bislang durch Leistungsregler geregelt. Im Falle einer Lastaenderung, wie sie beispielsweise beim Uebergang in den Betrieb auf ein Teilnetz (Insel-) mit vorher unbekannter Last vorkommt, trat ein Falschregeleffekt auf. Auf diesen wurden bereits Turbosatzausfaelle zurueckgefuehrt. Wird anstelle der elektrischen Leistung allerdings die innere Turbinenleistung geregelt, so tritt der Falschregeleffekt nicht ein. (orig.)

  17. Optimizing biological waste water cleaning by means of modern control systems (fuzzy logic); Optimierung der biologischen Abwasserreinigung durch moderne Regelsysteme (Fuzzy-Logik)

    Energy Technology Data Exchange (ETDEWEB)

    Lohse, M.; Boening, T.; Hegemann, G. [Fachhochschule Muenster (Germany). Inst. fuer Abfall- und Abwasserwirtschaft e.V.

    1999-07-01

    Within the framework of a project sponsored by EUREGIO, test series with the biological activation stages of a German and a Dutch sewage treatment plant each are carried out using different process concepts for the control of oxygen supply by fuzzy logic. As the currently available results demonstrate, the developed fuzzy-logic fields of characteristic curves permit establishing a stable and, thus, little energy-consuming process with optimum oxygen supply in comparison with conventional control. (orig.) [German] Im Rahmen eines von der EUREGIO gefoerderten Forschungsprojektes werden Versuchsreihen im Bereich der biologischen Belebungsstufen einer deutschen und einer niederlaendischen Abwasserreinigungsanlage (ARA) mit unterschiedlichen Verfahrenskonzepten hinsichtlich der Regelung der Sauerstoffzufuhr mit Hilfe der Fuzzy-Logik Technik durchgefuehrt. Die bisherigen Versuchsergebnisse zeigen, dass - im Vergleich zur konventionellen Regelung - durch die entwickelten Fuzzy-Logik Kennfelder ein stabiler und damit energiearmer Prozess mit optimaler Sauerstoffzufuhr erzeugt wird. (orig.)

  18. Minimisation of loads on the azimuthal drive by control of the slip brake momentum; Minimierung der Azimutantriebsbelastungen durch Steuerung des Schleifbremsen-Momentes

    Energy Technology Data Exchange (ETDEWEB)

    Boehmeke, G. [PVO Engineering OY, Helsinki (Finland)

    2000-07-01

    The influence of the slip brake momentum on the load acting on the azimuthal drives is investigated and is minimised by a variable, optimised braking momentum. An option for automatic control is proposed. Measures to improve the availability of wind power systems in cold climates were developed in the context of a development study, including closer investigations of the azimuthal region. [German] Der Einfluss des Schleifbremsenmomentes auf die Belastung der Azimut-Verstellantriebe wird untersucht und durch variables stets optimales Bremsmoment minimiert. Eine Option zur automatisierten Steuerung wird vorgeschlagen. Im Rahmen einer Entwicklungsstudie wurden Massnahmen zur Erhoehung der Betriebssicherheit von Windkraftanlagen in kaltem Klima ausgearbeitet, und unter anderem auch der Azimutbereich naeher untersucht. (orig.)

  19. Material modifications in lithium niobate and lithium tantalate crystals by ion irradiation; Materialmodifikationen in Lithiumniobat- und Lithiumtantalat-Kristallen durch Ionenbestrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Raeth, Niels Lennart

    2017-02-17

    ''. An explanation for the different behavior of the refractive index changes after irradiation of LiNbO{sub 3} and LiTaO{sub 3} is provided by the following model: The refractive index changes caused by effects such as volume increase, change in polar polarizabilities, and decrease of spontaneous polarization partially cancel each other out, so that the change of ordinary and extraordinary refractive index in LiNbO{sub 3} just coincidentally the same amount fails. In LiTaO{sub 3}, the compensating fraction is normally insufficient to cause a positive change in the extraordinary refractive index. [German] Die kuenstlich hergestellten Kristalle Lithiumniobat (LiNbO{sub 3}) und das eng verwandte Lithiumtantalat (LiTaO{sub 3}) sind bewaehrte Ausgangsmaterialien zur Herstellung aktiver und passiver Bauelemente, die Licht fuehren, verstaerken, schalten und verarbeiten koennen. Hierfuer ist es oft notwendig, den Brechungsindex des Substrats gezielt beeinflussen zu koennen, was neben anderer Methoden auch durch Bestrahlung der Materialien mit schnellen leichten Ionen moeglich ist. Im Rahmen dieser Arbeit werden Lithiumniobat- und Lithiumtantalat-Kristalle mit Alphateilchen, {sup 3}He-Ionen, Deuteronen und Protonen bei Projektilenergien von bis zu 14 MeV/Nukleon bestrahlt. Energie und Kristalldicke sind dabei so gewaehlt, dass die Projektile die gesamte Probe durchdringen und nicht implantiert werden. Alle fuer die unerwuenschte, durch die Bestrahlung entstehende, nukleare Aktivierung der Kristalle verantwortlichen Isotope sind relativ kurzlebig und insgesamt nimmt die Aktivierung schnell genug ab, um nach einer Lagerfrist von einigen Tagen bis wenigen Wochen den gefahrlosen Umgang mit den bestrahlten Proben zu ermoeglichen. Die in Lithiumniobat und Lithiumtantalat durch die Bestrahlung mit den verschiedenen Projektilen erzeugten Brechungsindexaenderungen werden interferometrisch bestimmt und koennen durch geeignete Wahl der Probengeometrie auch in Abhaengigkeit von der

  20. Integrated power-heat-cold-coupling by switchable Stirling-Vuilleumier-Hybrid-Machines; Integrierte Kraft-Waerme-Kaelte-Kopplung durch umschaltbare Stirling-Vuilleumier-Hybrid-Maschinen

    Energy Technology Data Exchange (ETDEWEB)

    Kuehl, Hans-Detlev [Technische Univ. Dortmund (Germany). Lehrstuhl fuer Thermodynamik

    2017-07-01

    experimental effort, a similarity-theoretical scaling was carried out while keeping all dimensionless parameters relevant to the internal gas circulation process constant. Although the experimental results presented in this article therefore require a correction due to some external, not correctly scalable friction and insulation losses, they nevertheless prove that the realization of such switchable systems for decentralized, demand-oriented energy supply of buildings in a practical size and performance class is possible. In coordinated operation of a larger number of such systems - e.g. via ripple control or network load-dependent power consumption tariffs and power feed-in tariffs - can respond by appropriate switching between the operating conditions on load fluctuations in the public grid and so valuable, short-term retrievable control energy can be provided. Furthermore, applications in the field of drive-independent air conditioning, heating and power supply of vehicles are conceivable. [German] Ein Stirlingmotor besteht in seiner sogenannten Gamma-Bauart zum einen aus einem thermischen Verdichter, in dem ein doppelseitig wirkender Verdraengerkolben das Arbeitsgas zwischen einem heissen'' und einem ''warmen'' (d. h. auf dem Waermenutzungstemperaturniveau der KWK-Anwendung befindlichen) Zylinderraum isochor ueber einen Regenerator periodisch hin- und herschiebt. Zum anderen besitzt er ein hiervon raeumlich getrenntes, einseitig wirkendes Arbeitskolben-Zylinder-System, das mit der ''warmen'' Seite des thermischen Verdichters durch einen Ueberstroemkanal verbunden ist und sich somit auf aehnlichem Temperaturniveau befindet. Fuegt man in diesen Ueberstroemkanal einen zusaetzlichen Regenerator ein, so kommt es zu einer Trennung der Temperaturniveaus, da die Waermeabgabe des Prozesses primaer ueber den warmen Zylinderraum des Verdraengersystems erfolgt, waehrend der Zylinderraum des Arbeitskolbens eine Waermesenke darstellt

  1. Transport of Phanerochaete chrysosporium and Mucor hiemalis f. irnsingii spores through water-saturated quartz sands; Transport von Phanerochaete chrysosporium- und Mucor hiemalis f. irnsingii-Sporen durch wassergesaettigten Quarzsand

    Energy Technology Data Exchange (ETDEWEB)

    Hoque, E.; Klotz, D.; Teichmann, G.; Lang, H.; Wolf, M. [GSF - Forschungszentrum fuer Umwelt und Gesundheit GmbH, Neuherberg (Germany). Inst. fuer Hydrologie; Beisker, W. [GSF, Inst. fuer Pathologie (Germany)

    2001-11-01

    Just as bacteria so can aquatic fungi contribute effectively to pollutant elimination, at least in superficial groundwaters. However, very little is known about this. Nor is it known whether fungal spores are capable of being transported through sedimentary cavities. At least fungal spores are for some part of similar size as bacteria. We here report for the first time on a demonstration of the migration through quartz sand of spores of the two fungal species Phanerochaete chrysosporium and Mucor hiemalis f. irnsingii. [German] Neben Bakterien koennen auch aquatische Pilze, zumindest im oberflaechennahen Grundwasser, effiziente Beitraege zur Schadstoffentgiftung leisten. Darueber ist aber sehr wenig bekannt. Es ist auch nicht bekannt, ob ueberhaupt Pilzsporen durch Sedimenthohlraeume transportiert werden koennen, obwohl die Pilzsporen z.T. aehnliche Abmessungen wie Bakterien haben. Hier berichten wir erstmalig ueber den Nachweis der Migration von Sporen der beiden Pilzarten Phanerochaete chrysosporium und Mucor hiemalis f. irnsingii durch Quarzsand. (orig.)

  2. Energy saving by enhanced temperature measurement of stock materials of heat- and heat treatment process. Final report; Energieeinsparung durch verbesserte Nutzguttemperaturbestimmung bei Waerm- und Waermebehandlungsprozessen. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Ley, I.; Klima, R.

    1999-06-01

    Thermoelementes, welches moeglichst gut im Strahlungsaustausch mit dem Nutzgut steht, gemessen. Somit kann die Oberflaechentemperatur weitgehend unabhaengig vom Emissionsgrad des Nutzgutes gemessen werden. Die Vorteile der Thermoelementsonde konnten durch eine Installation an einem Waermeofen und einer Waermebehandlungsanlage deutlich aufgezeigt werden. Durch die dauerhafte betriebliche Installation konnten umfangreiche Verbesserungsmassnahmen zur Energieeinsparung und zur Qualitaetsverbesserung an den Oefen realisiert werden. Die Thermoelementsonde ermoeglicht eine strenge Optimierung mittels modellgestuetzter Steuerung und damit deutliche Produktverbesserungen und Energieeinsparungen. (orig.)

  3. Purification of industrial effluents with a high load of organic pollutants by a combined anaerobic/aerobic process; Reinigung organisch hochbelasteter Industriebwaesser durch eine anaerob/aerobe Verfahrenskombination

    Energy Technology Data Exchange (ETDEWEB)

    Reidl, H.H. [AEW ESMIL GmbH fuer Wasser- und Abwassersyteme, Ratingen (Germany)

    1994-12-31

    Organically polluted sewage water can be economically cleaned in an aerobic biological sewage treatment plant with upstream anaerobic as this saves activation volume and ventilation energy. This was demonstrated in the sewage treatment plant of the PWA in Redenfelden, where an anaerobic stage was installed which uses the BIOTHANE{sup R} process. The CARROUSEL-system of the anaerobic stage has proved a istself both in the PWA ans in municipal plants between 5000 to 100000 EW. It is a robust system with uncomplicated control which guarantees observance of maximum values and allows elimation of P and N. (orig.) [Deutsch] Organisch hochbelastete Abwaesser werden oekonomisch durch eine aerobe biologische Klaeranlage mit vorgeschalteter Anaerobie gereinigt, weil dadurch Belebungsvolumen und Belueftungsenergie eingespart werden. Dies wurde am Beispiel der Abwasserreinigungsanlage der PWA Redenfelden gezeigt, bie der eine Anaerobstufe nach den BIOTHANE{sup R}-Verfahren installiert ist. Das dort eingesetzte CARROUSEL-System fuer die Aerobstufe hat sich sowohl bei der PWA als auch im kommunalen Bereich bei Anlagen zwischen 5000 und 100000 EW, als robustes System mit unkomplizierter Steuerung bewaehrt, das eine sichere Einhaltung der Grenzwerte garantiert und die Moeglichkeit zur P- und N-Elimination bietet. (orig.)

  4. Efficient sorting of waste by means of dry stabilisation and separation of inert materials; Effiziente Sortierung von Restabfall durch Trockenstabilisierung und Inertstoffabscheidung

    Energy Technology Data Exchange (ETDEWEB)

    Heering, B.M. [Herhof-Umwelt GmbH, Solms-Niederbiel (Germany); Heil, J. [Lehr- und Forschungsgebiet Kokereiwesen, Brikettierung und Thermische Abfallbehandlung, Aachen (Germany)

    1999-07-01

    Sorting of waste takes place in two stages: First, the waste is dried to a moisture of 15 % by weight, making use of its microbial activities. After this, the stabilised residue is sorted according to grain size, density, magnetic susceiptibility, electric conductivity, and comminution characteristics. This way, recyclable materials are recovered almost completely (e.g. metals, stone, ceramics, glass). The refuse-derived fuel fraction has significantly lower heavy metal concentrations because the metals were sorted out, and its calorific value and homogemeity are optimised as well. The fuel fraction can be combusted at once or stored for further use. [German] Die stoffliche Trennung des Restabfalls kann in zwei aufeinander folgende Schritte unterteilt werden. Den ersten Schritt stellt eine Trocknung unter Ausnutzung der mikrobiellen Aktivitaeten des Materials dar. Durch diese Massnahme wird ein trockenes Material mit einer Restfeuchte von unter 15 Gew.-% erzeugt. Den zweiten Verfahrensschritt stellt die Sortierung des stabilisierten Restabfall dar. Als Sortierkriterium werden die Eigenschaften Korngroesse, Dichte, magnetische Suszeptibilitaet, elektrische Leitfaehigkeit und Zerkleinerungsverhalten angewandt. Hierdruch ist eine nahezu vollstaendige und sortenreine Rueckgewinnung der im Abfall enthaltenen Wertstoffe wie Eisen-/Nichteisenmetalle, Steine/Keramik und Glas sichergestellt. Weiterhin erhaelt man als Brennstofffraktion das Trockenstabilat {sup circledR}. Aufgrund der Abtrennung der hauptsaechlichen Schwermetalltraeger, Eisen- und Nichteisenmetalle, besitzt dieser Sekundaerbrennstoff gegenueber dem unbehandeltem Restabfall deutlich verminderte Schwermetallkonzentrationen. Zudem sind seine verbrennungstechnisch relevanten Eigenschaften Heizwert und Homogenitaet deutlich optimiert. Das Trockenstabilat {sup circledR} wird sofort oder zeitversetzt der energetischen Verwertung zugefuehrt. (orig.)

  5. THERMOSELECT. Continuous environment-friendly treatment of residues by gasification and direct melting; THERMOSELECT. Unterbrechungslose umweltgerechte Restabfallbehandlung durch Vergasung und Direkteinschmelzung

    Energy Technology Data Exchange (ETDEWEB)

    Gaeng, P.; Klein, K.; Stahlberg, R.; Weisenburger, P. [Thermoselect Suedwest GmbH, Karlsruhe (Germany)

    1996-12-31

    The Thermoselect process comprises waste compaction, degassing, gasification with pure oxygen, and melting of inorganic components in a continuous closed cycle process. The high-quality products can be recycled almost completely: The synthesis gas can be used as feedstock or combusted, also in high-efficiency power generation processes. The other products, e.g. the high-grade mineral and metal granulates, can be utilized without restrictions. The residual fraction which must be dumped is very small. (orig) [Deutsch] Mit Thermoselect ist eine neue Technik auf dem Markt, die durch die konsequente Umsetzung der Verfahrensschritte Abfallverdichtung, Entgasung, Vergasung mit reinem Sauerstoff und Einschmelzung der anorganischen Muellbestandteile in einem unterbrechungslosen geschlossenen Prozess hochwertige Produkte aus Abfaellen erzeugt, die nahezu vollstaendig verwertet werden koennen. Das erzeugte Synthesegas kann sowohl stofflich als auch thermisch genutzt werden, wobei der Einsatz von stromerzeugungsverfahren mit hohen Wirkungsgraden moeglich ist. Die ubrigen Produkte, z.B. das mineralische und das metallische Granulat, erreichen eine Qualitaet, die eine uneingeschraenkte Nutzung zulaesst. Die Anteile der z.Zt. noch zu entsorgenden Reststoffe ist gering, wobei derzeit meist wirtschafatliche Gruende deren Entsorgung nahelegen. (orig)

  6. Use of dexpanthenol and aloe vera to influence the irradiation response of the oral mucous membrane (mouse); Beeinflussung der Strahlenreaktion der Mundschleimhaut (Maus) durch Dexpanthenol {+-} Aloe vera

    Energy Technology Data Exchange (ETDEWEB)

    Schlichting, S. [Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie, Dresden Univ. (Germany); Spekl, K.; Doerr, W. [Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie, Dresden Univ. (Germany)]|[Experimentelles Zentrum, Medizinische Fakultaet Carl Gustav Carus, Dresden Univ. (Germany)

    2004-07-01

    In summarising the outcome of the present study it can be said spraying the agent on the oral mucous membrane once a day had an effect on the incidence of mucous membrane ulceration in the case of both placebo and dexpanthenol treatment. However, there was no significant difference between placebo and dexpanthenol treatment, the only finding being a slight prolongation of latency time through aloe vera. These experimental findings give good reason to critically reconsider the clinical use of dexpanthenol as a supportive treatment for the prevention of radiogenic mucositis enoralis following irradiation of tumours in the head and neck region. However thorough oral lavage is an effective means of moderating the irradiation response of the oral mucous membrane. [German] Zusammenfassend ist festzustellen, dass in den vorliegenden Versuchen mit einmal taeglichem Aufspruehen des Praeparates auf die Mundschleimhaut sowohl die Placebo - wie auch die Dexpanthenol-Behandlung die Inzidenz von Schleimhautulzerationen modifiziert hat; zwischen Placebo- und Dexpanthenol-Behandlung ergab sich jedoch kein signifikanter Unterschied. Lediglich eine geringe Verlaengerung der Latenzzeit durch Aloe vera war zu beobachten. Auf der Basis dieser experimentellen Ergebnisse muss der klinische Einsatz von Dexpanthenol im Rahmen der Supportivtherapie zur Prophylaxe der radiogenen Mucositis enoralis bei der Bestrahlung von Kopf-Hals-Tumoren kritisch ueberdacht werden. Regelmaessige, intensive Mundspuelungen sind jedoch ein probates Mittel zur Verminderung der Strahlenreaktion der Mundschleimhaut. (orig.)

  7. THERMOSELECT. Continuous environment-friendly treatment of residues by gasification and direct melting; THERMOSELECT. Unterbrechungslose umweltgerechte Restabfallbehandlung durch Vergasung und Direkteinschmelzung

    Energy Technology Data Exchange (ETDEWEB)

    Gaeng, P; Klein, K; Stahlberg, R; Weisenburger, P [Thermoselect Suedwest GmbH, Karlsruhe (Germany)

    1997-12-31

    The Thermoselect process comprises waste compaction, degassing, gasification with pure oxygen, and melting of inorganic components in a continuous closed cycle process. The high-quality products can be recycled almost completely: The synthesis gas can be used as feedstock or combusted, also in high-efficiency power generation processes. The other products, e.g. the high-grade mineral and metal granulates, can be utilized without restrictions. The residual fraction which must be dumped is very small. (orig) [Deutsch] Mit Thermoselect ist eine neue Technik auf dem Markt, die durch die konsequente Umsetzung der Verfahrensschritte Abfallverdichtung, Entgasung, Vergasung mit reinem Sauerstoff und Einschmelzung der anorganischen Muellbestandteile in einem unterbrechungslosen geschlossenen Prozess hochwertige Produkte aus Abfaellen erzeugt, die nahezu vollstaendig verwertet werden koennen. Das erzeugte Synthesegas kann sowohl stofflich als auch thermisch genutzt werden, wobei der Einsatz von stromerzeugungsverfahren mit hohen Wirkungsgraden moeglich ist. Die ubrigen Produkte, z.B. das mineralische und das metallische Granulat, erreichen eine Qualitaet, die eine uneingeschraenkte Nutzung zulaesst. Die Anteile der z.Zt. noch zu entsorgenden Reststoffe ist gering, wobei derzeit meist wirtschafatliche Gruende deren Entsorgung nahelegen. (orig)

  8. Control-technical optimization of topped denitrification through fuzzy control; Regelungstechnische Optimierung der vorgeschalteten Denitrifikation durch Anwendung von Fuzzy-Control

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, U. [Hydroplan Ingenieurgesellschaft, Worms (Germany); Poepel, H.J. [Technische Univ. Darmstadt (Germany). Inst. WAR - Wasserversorgung, Abwassertechnik, Abfalltechnik, Umwelt- und Raumplanung

    1999-07-01

    The present paper describes complex fuzzy systems for controlling nitrogen elimination at plants with topped denitrification. For the design and testing of the fuzzy systems, dynamic simulation calculations and experimental tests were carried out in a semi-technical pilot plant. The controlling fuzzy systems indicate the supposed oxygen values for individual tank areas and the most appropriate partitioning of the activated sludge tank (anoxic/aerobic zone) as a function of the input quantities used. It is established that, with the more flexible control behaviour, a more stable nitrogen elimination and, at the same time, a cut in the amount of air transferred to the system can be attained in comparison with a conventional control. (orig.) [German] Im Rahmen dieses Beitrags werden komplexe Fuzzy-Systeme zur Regelung der Stickstoffelimination in Anlagen mit vorgeschalteter Denitrifikation vorgestellt. Zum Entwurf und zur Erprobung der Fuzzy-Systeme wurden dynamische Simulationsrechnungen und experimentelle Untersuchungen an einer halbtechnischen Versuchsanlage durchgefuehrt. Die uebergeordneten Fuzzy-Systeme geben in Abhaengigkeit der verwendeten Eingangsgroessen Sauerstoffsollwerte fuer die einzelnen Beckenbereiche und die jeweils guenstigste Aufteilung des Belebungsbeckens (anoxische/aerobe Zone) vor. Die Ergebnisse zeigen, dass durch das flexible Reglerverhalten eine stabilere Stickstoffelimination und gleichzeitig eine Einsparung an eingetragener Luftmenge im Vergleich zu einem konventionellen Regelsystem erreicht werden kann. (orig.)

  9. Self-management by firm, non-elastic adjustable compression wrap device [Translation of Druckmessungen unter Klettverschluss-Kompression - Selbstbehandlung durch feste, unelastische Beinwickelung

    Directory of Open Access Journals (Sweden)

    Giovanni Mosti

    2017-09-01

    Full Text Available Severe forms of chronic venous insufficiency and lymphedema require strong compression-pressure, which exceeds the pressure exerted by medical compression stockings (>40 mmHg. The aim was to investigate if patients are able to apply a Velcro-band compression device (Circaid Juxta Lite™ themselves with sufficient pressure. Thirty-one patients (CEAP C6=23, C5=5, C3=2, mixed ulcer=1 applied Juxta Lite™ on their own legs after a short instruction and were asked to readjust the pressure by their subjective feeling. Sub- bandage pressure was measured after application and 24 h later. In 30 patients without arterial occlusive disease the median sub- bandage pressure values on day 1 and day 2 were 44,5 mmHg (IQR 42-48, and 46 mmHg (IQR 44-48,25 respectively. One patient with an arterialvenous leg ulcer showed pressures of 34 and 36 mmHg. All measured pressure values corresponded to the pursued target range, demonstrating that adequate self application of Velcro bands is feasible and that patents can maintain this pressure by re-adjustment. Source: this paper is an abridged translation of Mosti G, Partsch H. Druckmessungen unter Klettverschluss-Kompression - Selbstbehandlung durch feste, unelastische Beinwickelung. Vasomed 2017;5:212-6.

  10. Catalytic oxidation using nitrous oxide

    Directory of Open Access Journals (Sweden)

    Juan Carlos Beltran-Prieto

    2017-01-01

    Full Text Available Nitrous oxide is a very inert gas used generally as oxidant as it offers some advantage compared with other oxidants such as O2 but a considerably higher temperature (> 526 °C is often required. For particular cases such as the oxidation of sugar alcohols, especially for the oxidation of primary alcohols to aldehydes, N2O has the advantage over O2 of a higher reaction selectivity. In the present paper we present the modelling of oxidation reaction of sugar alcohols using an oxidizing agent in low concentrations, which is important to suppress subsequent oxidation reactions due to the very low residual concentrations of the oxidizing agent. For orientation experiments we chose nitrous oxide generated by thermal decomposition of ammonium nitrate. Kinetic modeling of the reaction was performed after determination of the differential equations that describe the system under study.

  11. Substitution of wastes for fuels and raw materials in high-temperature processes; Substitution von Brennstoffen und Rohstoffen durch Abfaelle in Hochtemperaturprozessen

    Energy Technology Data Exchange (ETDEWEB)

    Scholz, R. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). Inst. fuer Energieverfahrenstechnik; Beckmann, M. [Clausthaler Umwelttechnik-Institut GmbH (CUTEC), Clausthal-Zellerfeld (Germany)

    1998-09-01

    burning processes in the cement industry. To do justice to the steel and iron industry it also deals with fuel substitution in a natural gas fired cokeless cupola furnace. [Deutsch] Die energetische und die stoffliche Verwertung von Abfaellen ist ein bereits seit langem diskutiertes Thema. Dabei interessieren zunaechst die Fragestellungen im Zusammenhang mit dem jeweils spezifischen Einsatz wie z.B. bei der Co-Verbrennung von Klaerschlamm in Kraftwerksfeuerungen, der Substitution von Primaerbrennstoffen durch Kunststoffabfaelle beim Brennprozess in der Zementindustrie usw. Darueber hinaus wird weiter der Vergleich der jeweiligen Anwendung untereinander sowie die Gegenueberstellung mit den zum Stand der Technik gehoerenden thermischen Abfallbehandlungsverfahren diskutiert. Diese Verfahrensvergleiche muessen selbstverstaendlich unter Einbeziehung aller insgesamt erforderlichen Aufwendungen an Zusatzstoffen und Zusatzenergie mit gleichen Randbedingungen durchgefuehrt werden. Dabei sind u.a. die sich aus den spezifischen Eigenschaften der Abfallstoffe fuer den jeweiligen Anwendungsfall ergebenden Besonderheiten zu beruecksichtigen. Das betrifft insbesondere die Auswirkungen einer Substitution von Primaerbrennstoffen durch Ersatzbrennstoffe aus Abfaellen (Sekundaerbrennstoffe) z.B. bei einem Brennprozess auf die Waermeuebertragungsbedingungen, die Stroemungsverhaeltnisse und damit zusammenhaengend auf die Temperaturverteilungen, den Guttransport und den spezifischen Energieaufwand. Ersatzbrennstoffe muessen sich sowohl aus stofflicher Sicht als auch aus brennstoff- und waermetechnischer Sicht fuer eine Substitution eignen. In dem vorliegenden Beitrag wird insbesondere auf die Anforderungen an Abfaellen, die zur Substitution von Primaerbrennstoffen dienen aus brennstoff- und waermetechnischer Sicht eingegangen. Hierzu werden zunaechst kurz einige wesentliche Gesichtspunkte der Waermeuebertragung in Feuerungen und Industrieoefen eroertert. Wichtig fuer die Bewertung einer

  12. Degradation of organic pollutants in sewage sludge by aerobic-thermophilic sludge treatment. Final report; Abbau organischer Schadstoffe im Klaerschlamm durch aerob-thermophile Schlammbehandlung. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Prechtl, S.

    1999-07-01

    Klaerschlamm. Im organischen Anteil des Klaerschlammfeststoffes sind bis heute ueber 300 verschiedene organische Spurenstoffe nachgewiesen worden. Neben den in der Klaerschlammverordnung erfassten Stoffgruppen (Dioxine/Furane und PCB) sind weitere Stoffgruppen als relevant eingestuft worden. Um die in diesem Bereich z.T. noch unzureichende Datenlage zu erweitern wurde im Forschungsvorhaben die Moeglichkeit untersucht, durch eine aerob-thermophile Schlammbehandlung (ATS) eine Verbesserung der Klaerschlammqualitaet, bei der Stoffgruppe der Phthalate (Di-(2-ethylhexyl)phthalat), den polyzklischen aromatischen Kohlenwasserstoffen (PAK) und beim 4-Nonylphenol (Abbauprodukt von nichtionischen Tensiden), zu erreichen. Zur Beurteilung der Abbaueffektivitaet aus der komplexen Matrix Klaerschlamm bildete die Schadstoffanalytik mittels HPLC und GC/MS einen Schwerpunkt des Vorhabens. Der Gehalt an Di-(2-ethylhexyl)phthalat (DEHP) und 4-Nonylphenol (4-NP) konnte in Laborversuchen mit dotierten Schlaemmen um 70% bzw. 50% und in undotierten Schlaemmen um 61% bzw. 53% reduziert werden. Bei halbtechnischen Versuchen lag die Reduktion fuer DEHP bei 14% und fuer 4-NP bei 68%. Fuer Pyren liess sich in Laborversuchen ein Abbau bis zu 57% erreichen, im Vergleich zu halbtechnischen Untersuchungen mit 22% Abbau. Die Ergebnisse erster grundlegender Untersuchungen zu einer Verfahrenskombination aus verkuerzter Faulstufe und ATS-Folgestufe zeigten fuer DEHP eine Reduktion von ca. 60%. Der Gehalt an einzelnen PAK konnten bis Anthracen reduziert werden. Fuer hoeherkondensierte PAK (Grundbelastung im ppb-Bereich) ergab sich keine einheitliche Aussage. Ein Abbau von 4-NP wurde bei den Versuchen zur Verfahrenskombination durch die Neubildung von 4-NP aus Alkylphenolethoxylaten unter anaeroben und aeroben Bedingungen ueberdeckt. Die erhaltenen Untersuchungsergebnisse bestaetigen die Korrelation zwischen einer Hygienisierung des Klaerschlamms und der entsprechenden Verweilzeit im Reaktorsystem. Sowohl in der

  13. Epiphyseal injuries of the distal tibia. Does MRI provide useful additional information?; Epiphysenfugenverletzungen der distalen Tibia. Sinnvolle Mehrinformation durch die MRT?

    Energy Technology Data Exchange (ETDEWEB)

    Iwinska-Zelder, J.; Schmidt, S.; Ishaque, N.; Klose, K.J.; Hoppe, M. [Marburg Univ. (Germany). Abt. fuer Strahlendiagnostik; Schmitt, J.; Gotzen, L. [Marburg Univ. (Germany). Medizinisches Zentrum fuer Operative Medizin

    1999-01-01

    Plain film radiography often underestimates the extent of injury in children with epiphyseal fracture. Especially Salter-Harris V fractures (crush fracture of the epiphyseal plate) are often primarily not detected. MRI of the ankle was performed in 10 children aged 9-17 (mean 14) years with suspected epiphyseal injury using 1.0-T Magnetom Expert. The fractures were classified according to the Salter-Harris-Rang-Odgen classification and compared with the results of plain radiography. In one case MRI could exclude epiphyseal injury; in four cases the MRI findings changed the therapeutic management. The visualisation of the fracture in three orthogonal planes and the possibility of detection of cartilage and ligamentous injury in MR imaging makes this method superior to conventional radiography and CT. With respect to radiation exposure MRI instead of CT should be used for the diagnosis of epiphyseal injuries in children. (orig.) [Deutsch] Die konventionelle Roentgendiagnostik unterschaetzt haeufig das Ausmass der kindlichen Extremitaetenfrakturen mit Epiphysenbeteiligung (Typ Salter-Harris). Insbesondere werden die Kompressionsfrakturen der Wachstumsfuge (Salter-Harris V) primaer haeufig nicht erkannt. Prospektiv wurden 10 Kinder im Alter von 9-17 Jahren (Durchschnittsalter = 14 J.) mit Verdacht auf eine epiphysaere Fraktur der distalen Tibia magnetresonanztomographisch (1.0-Tesla Magnetom Expert), untersucht. Die MRT-Ergebnisse wurden auf der Basis der Klassifikation nach Salter-Harris-Rang-Odgen mit den konventionellen Roentgenbildern verglichen. In einem Fall, bei einem 15jaehrigen Patienten, gelang durch die MRT der Ausschluss einer epiphysaeren Verletzung. In 7 Faellen fuehrte der MRT-Einsatz zu einer Aenderung der Klassifikation nach Salter-Harris. Hieraus resultierte bei 4 Patienten ein Therapiewechsel. Da Frakturen, die sie begleitenden Knorpellaesionen und ligamentaere Verletzungen multiplanar dargestellt werden koennen, weist die MRT deutliche Vorteile

  14. Low emission transport systems. Reduction of emissions with low-pollutant lubricants; Emissionsarmer Verkehr. Emissionsminderung durch schadstoffarme Schmierstoffe

    Energy Technology Data Exchange (ETDEWEB)

    Keller, D; Boehncke, A; Mangelsdorf, I

    2001-07-01

    Due to the lower EURO 4 emission limits, exhaust aftertreatment systems for heavy- and light-duty vehicles will be necessary which are more efficient than the today 3-way- or oxidation-type catalysts. Practicable exhaust aftertreatment systems are, for example, particle traps, SCR or NOx- adsorber catalysts, and combinations of these systems. Most of these exhaust control devices require fuels with sulphur contents below 10 ppm. Then the sulphate emissions from lubricants containing about 0.5% sulphur is in the same order of magnitude as sulphate emissions from low sulfur fuels. Measured data on the influence of sulphur from lubricating oils on future exhaust treatment systems are very limited. Conclusions have mostly been drawn from experimental results with low sulphur fuels. It cannot be ruled out, especially for NOx- adsorbers, that sulphur will adversely affect performance, thus making a reduction of sulphur levels in engine oils necessary. As far as diesel exhaust is concerned lubricants contribute approximately 20 - 26% to total particulate matter and more than 50% to the soluble organic fraction (SOF). Ash deposits derived from additives that contain zinc, calcium, sulphur, or phosphorous are likely to block the newly developed particle filter systems. Also for diesel technologies incorporating precious-metal catalysts (e.g. DOC, CDPF, CR-DPF, Urea- SCR) low sulphur levels are advantageous because the mass of sulphate particulate matter formed from fuel or lubricant sulphur is reduced. Conventional three-way catalysts are less sensitive, the light-off temperature being mainly affected. In summary, all available studies suggest that the lower the level of sulphur the lower emissions are. Furthermore phosphorous (associated with the antiwear additive ZDTP) was shown to limit catalyst life and, together with thermal degradation, is responsible for reduced catalyst efficiency over time. Although there is still a lack of quantitative technical information, it

  15. Study on the planning of a demonstration plant for hydrogen fuel production by electrolysis using caching in salt caverns under pressure; Studie ueber die Planung einer Demonstrationsanlage zur Wasserstoff-Kraftstoffgewinnung durch Elektrolyse mit Zwischenspeicherung in Salzkavernen unter Druck

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-02-05

    In a two year research project the long-term storage of hydrogen as energy carrier has been assessed in detail for large renewable electricity quantities in underground storage caverns in Germany. Next to a regions analysis for potential storage sites, the benchmarking against other large scale storage concepts, a comparative and perspective analysis of alkaline and PEM-electrolysers also potential business cases for Power-to-Hydrogen in the mobility sector as well as for the chemical, electricity and natural gas industry have been analysed. [German] Durch den geplanten Ausbau der Stromerzeugung aus fluktuierenden, erneuerbaren Energien in Deutschland ruecken Speichertechnologien fuer elektrische Energie immer staerker in den Fokus des industriellen und politischen Interesses. Eine vielversprechende Moeglichkeit fuer eine Langzeitspeicherung bei hohen Anteilen von Wind- und Photovoltaikanlagen sind Speichertechnologien wie die Wasserstoffspeicherung mit Hilfe von Wasserelektrolyseuren. Diese koennen erneuerbaren Strom in grossen Mengen und bei entsprechender Steuerung selektiv in Zeiten mit hohem Dargebot z.B. an Windstrom chemisch speichern. Der gespeicherte Wasserstoff kann dann entweder zu einem spaeteren Zeitpunkt wieder rueckverstromt oder direkt stofflich verwertet werden, z.B. als Kraftstoff fuer den Verkehrssektor, als chemischer Rohstoff oder fuer den Hausenergiebereich durch Einspeisung in das Erdgastransportnetz. Thema der vorliegenden Studie sind Analysen und Planungen fuer die Erprobung des Gesamtsystems ''Wasserstoff-Elektrolyse-Speicherung'' in energiewirtschaftlich relevanten Dimensionen. Dazu werden mit einem neuen Ansatz techno-oekonomische Entwicklungspfade fuer Wasserstoff-Systeme unterschiedlicher Groesse und Technologien charakterisiert und technologische Risiken bei der Realisierung dieser Systeme identifiziert und bewertet. Diese Arbeiten werden ergaenzt durch Arbeiten auf dem Gebiet der Salzkavernenspeicherung in Form

  16. Optimizing customer contact management to bolster loyalty and profitability. Optimizing specifically quality of service and cost; Loyalitaet und Profitabilitaet von Privat- und Gewerbekunden durch optimiertes Kundenkontaktmanagement steigern. Servicequalitaet und Kosten zielgerichtet optimieren

    Energy Technology Data Exchange (ETDEWEB)

    Hillebrand, S.; Fratzke-Weiss, B.; Handschuh, M.; Muench, U.; Kreuz, W. [A.T. Kearney Management Consultants, Frankfurt/Main (Germany)

    2003-09-08

    Building on the sales strategy, the customer care center's processes, systems, and organization can be optimized in a focused way. Based on the set of success factors described by the authors private and commercial customers' value can be increased significantly. (orig.) [German] Eine klar definierte Vertriebsstrategie ist von elementarer Bedeutung, um das Kundenkontaktmanagement so auszurichten, dass es maximalen Wert fuer das Unternehmen generiert. Ausgehend von der Vertriebsstrategie koennen die Prozesse, die Systeme und die Organisation von Customer Care Centern zielgerichtet optimiert werden. Durch die Beruecksichtigung der von den Verfassern beschriebenen Erfolgsfaktoren kann der Wert von Privat- und Gewerbekunden dabei signifikant gesteigert werden. (orig.)

  17. Oxide ceramics

    International Nuclear Information System (INIS)

    Ryshkewitch, E.; Richerson, D.W.

    1985-01-01

    The book explores single-phase ceramic oxide systems from the standpoint of physical chemistry and technology. This second edition also focuses on advances in technology since publication of the original edition. These include improvements in raw materials and forming and sintering techniques, and the major role that oxide ceramics have had in development of advanced products and processes. The text is divided into five major sections: general fundamentals of oxide ceramics, advances in aluminum oxide technology, advances in zirconia technology, and advances in beryllium oxide technology

  18. Climate protection by reducing the emissions of greenhouse gases in households and the tertiary sector through climate-conscious behaviour. Vol. 2; Klimaschutz durch Minderung von Treibhausgasemissionen im Bereich Haushalte und Kleinverbrauch durch klimagerechtes Verhalten. Bd. 2. Gewerbe, Handel und Dienstleistung

    Energy Technology Data Exchange (ETDEWEB)

    Boede, U; Gruber, E [Fraunhofer-Institut fuer Systemtechnik und Innovationsforschung (ISI), Karlsruhe (Germany); Deutscher, P; Elsberger, M; Rouvel, L [Technische Univ., Muenchen (Germany). Lehrstuhl fuer Energiewirtschaft und Innovationsforschung; Brakhage, A; Jaekel, M [Abacus, Trier (Germany); Renner, G [Innovative Energieberatung, Koeln (Germany); Brohmann, B; Cames, M; Herold, A

    2000-08-01

    The aim of the project was to identify areas in households and the tertiary sector in which changes in behaviour could result in energy conservation and thus a reduction of greenhouse gas emissions, and to quantify the potentials for 1995, 2005 and 2020. A second focus was on the analysis and evaluation of programmes and instruments to realise the potentials. With literature evaluation, expert interviews, and a household servey potentials and further technical development have been identified. In sum, behavioural measures can contribute to the CO2 reduction by 64 million tons in 1995 in households and 27 in the commercial sector in which the potential decreases to 18 million tons in 2020 due to the autonomous technical development. Adequate promotion programmes can help to realise 20-30% of the potential by 2020. (orig.) [German] Ziel des Vorhabens war, im Sektor private Haushalte und Kleinverbrauch Bereiche zu identifizieren, in denen Verhaltensaenderungen zur Energieeinsparung fuehren koennen, und diese Potenziale fuer 1995, 2005 und 2020 zu quantifizieren. Darauf aufbauend waren Programme und Instrumente zur Umsetzung aufzuzeigen und zu bewerten. Gestuetzt auf Literaturrecherchen und Expertengespraeche wurden Einzelpotenziale, Rahmenbedingungen, Entwicklungstrends in der Technik und im Ausstattungsgrad ermittelt. Insgesamt koennten Verhaltensmassnahmen im Haushaltssektor die CO2-Emissionen im Basisjahr 1995 um 64 Mio, im Kleinverbrauch um 27 Mio t vermindern. Bis 2020 bleibt dieses Potenzial im Haushaltssektor in etwa gleich. Im Kleinverbrauch sinkt es infolge der autonomen Technikentwicklung auf 18 Mio t ab. Durch geeignete Programme koennen bis 2020 etwa 20-30% des Potenzials erreicht werden. (orig.)

  19. Instruments. Climate protection of reduction of no-load losses in electric appliances and equipment; Klimaschutz durch Minderung von Leerlaufverlusten bei Elektrogeraeten. Instrumente

    Energy Technology Data Exchange (ETDEWEB)

    Rath, U.; Hellmann, R. [Ingenieurbuero fuer Energieberatung, Haustechnik und Oekologische Konzepte GbR (eboek), Tuebingen (Germany); Moehring-Hueser, W.; Wortmann, K.; Bregas, J. [Energiestiftung Schleswig-Holstein, Kiel (Germany); Mordziol, C. [Umweltbundesamt, Berlin (Germany)

    1999-12-01

    Two studies on the subject of 'Climate Protection through Reduction of No-load Losses in Electric Applicances and Equipment' have been performed on behalf of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety and the German Federal Environmental Agency. The first study, carried out by the Tuebingen-based engineering bureau eboek, has been published in the Federal Environmental Agency's TEXTE series (Texte 45/97, 2{sup nd} edition, 1998). It was the starting point for a multitude of activities among them two information campaigns carried out in 1998 and 1999 that were funded by the Federal Ministry for the Environment and the German Section of the Friends of the Earth (BUND). The study also served as a basis for decisions taken by the German Bundestag and the Bundesrat (Council of Constituent States). The second study on the subject was carried out by the engineering bureau eboek and Energiestiftung Schleswig-Holstein. Building on the results obtained in the first study, it presents estimates of relevant data for the European Union and examines various approaches for possible measures to reduce no-load losses as to their suitability. The studies impressively show that effective climate protection can be achieved in all relevant sectors, and in many cases even save costs. The results are detailed below. (orig.) [German] Im Auftrag des Bundesministeriums fuer Umwelt, Naturschutz und Reaktorsicherheit sowie des Umweltbundesamtes wurden zwei Studien zum Thema: 'Klimaschutz durch Minderung von Leerlaufverlusten bei Elektrogeraeten' durchgefuehrt: Die erste, vom Ingenieurbuero fuer Energieberatung, Haustechnik und oekologische Konzepte (eboek), Tuebingen, earbeitete Studie wurde in der Reihe TEXTE des UBA veroeffentlicht (Texte 45/97, 2. Auflage 1998). Sie bildete den Ausgangspunkt fuer eine Vielzahl von Aktivitaeten, unter anderem zwei vom Bundesumweltministerium finanzierte und vom Bund fuer Umwelt und

  20. Workflow improvement and efficiency gain with near digitalization of a Radiology Department; Workflowverbesserung und Effizienzsteigerungsaspekte durch nahezu vollstaendige Digitalisierung einer Roentgenabteilung

    Energy Technology Data Exchange (ETDEWEB)

    Langen, H.L.; Bielmeier, J.; Selbach, R. [Missionsaerztlichen Klinik Wuerzburg (Germany). Radiologische Abteilung; Wittenberg, G. [Univ. Wuerzburg (Germany). Inst. fuer Roentgendiagnostik; Feustel, H. [Missionsaerztlichen Klinik Wuerzburg (Germany). Chirurgische Abteilung

    2003-10-01

    Purpose: To determine the temporal changes of the workflow caused by digitalization of the radiology department after installation of digital luminescence-radiography (DLR), a radiology information system (RIS) and picture archiving and communication system (PACS) at the Missionsaerztliche Klinik in April 2000. Materials and methods: In a comparative study, a workflow analysis by manual registration of different work steps was performed before (1999) and after (2001) digitalization of a radiology department. Results: The digitalization shortened the examination time for patients from a mean of 8 min to 5 min. The time the patient is absent from the emergency room did not change. Reporting radiographic examinations including comparison with previous studies begins earlier from a mean of 2 h 37 min to 17 min. Using PACS, 85.9% of all cases could be interpreted on the day of the examination (without PACS 41.2%) and 87.2% of the reports were completed the day after the examination (without PACS 64.5%). No time differences were found between reading conventional studies on the monitor or as soft-copy. Conclusion: Compared to conventional film-screen systems, complete digitalization of a radiology department is time saving at nearly all steps of the workflow, with expected positive effects on the workflow quality of the entire hospital. (orig.) [German] Fragestellung/Zielsetzung: An der Missionsaerztlichen Klinik folgte im April 2000 mit der Einfuehrung der digitalen Lumineszenzradiographie (DLR), eines radiologischen Informationssystems (RIS) und eines Bildarchivierungs- und Kommunkationssystems (PACS) die vollstaendige Digitalisierung der Roentgenabteilung. Die durch diese Umstellung bedingten zeitlichen Veraenderungen der Prozessablaeufe in der Roentgenabteilung wurden untersucht. Material und Methode: In Form einer Vorher-Nachher-Studie wurde 1999 im konventionellen und 2001 im digitalen Routinebetrieb anhand von Analysen der Prozessablaeufe eine manuelle

  1. Instruments. Climate protection of reduction of no-load losses in electric appliances and equipment; Klimaschutz durch Minderung von Leerlaufverlusten bei Elektrogeraeten. Instrumente

    Energy Technology Data Exchange (ETDEWEB)

    Rath, U; Hellmann, R [Ingenieurbuero fuer Energieberatung, Haustechnik und Oekologische Konzepte GbR (eboek), Tuebingen (Germany); Moehring-Hueser, W; Wortmann, K; Bregas, J [Energiestiftung Schleswig-Holstein, Kiel (Germany); Mordziol, C [Umweltbundesamt, Berlin (Germany)

    1999-12-01

    Two studies on the subject of 'Climate Protection through Reduction of No-load Losses in Electric Applicances and Equipment' have been performed on behalf of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety and the German Federal Environmental Agency. The first study, carried out by the Tuebingen-based engineering bureau eboek, has been published in the Federal Environmental Agency's TEXTE series (Texte 45/97, 2{sup nd} edition, 1998). It was the starting point for a multitude of activities among them two information campaigns carried out in 1998 and 1999 that were funded by the Federal Ministry for the Environment and the German Section of the Friends of the Earth (BUND). The study also served as a basis for decisions taken by the German Bundestag and the Bundesrat (Council of Constituent States). The second study on the subject was carried out by the engineering bureau eboek and Energiestiftung Schleswig-Holstein. Building on the results obtained in the first study, it presents estimates of relevant data for the European Union and examines various approaches for possible measures to reduce no-load losses as to their suitability. The studies impressively show that effective climate protection can be achieved in all relevant sectors, and in many cases even save costs. The results are detailed below. (orig.) [German] Im Auftrag des Bundesministeriums fuer Umwelt, Naturschutz und Reaktorsicherheit sowie des Umweltbundesamtes wurden zwei Studien zum Thema: 'Klimaschutz durch Minderung von Leerlaufverlusten bei Elektrogeraeten' durchgefuehrt: Die erste, vom Ingenieurbuero fuer Energieberatung, Haustechnik und oekologische Konzepte (eboek), Tuebingen, earbeitete Studie wurde in der Reihe TEXTE des UBA veroeffentlicht (Texte 45/97, 2. Auflage 1998). Sie bildete den Ausgangspunkt fuer eine Vielzahl von Aktivitaeten, unter anderem zwei vom Bundesumweltministerium finanzierte und vom Bund fuer Umwelt und Naturschutz (BUND) 1998 und

  2. MTBE experts' discussion: Environmental pollution from MTBE fuel additives. Proceedings; MTBE-Fachgespraech: Umweltbelastungen durch die Nutzung von MTBE (Methyl-tertiaer-butylether) als Kraftstoffzusatz. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    Normalbenzin bei uns durchschnittlich 0,3% und Super 1,6% MTBE enthalten, liegen die Werte fuer SuperPlus und Optimax bei etwa 6-12% Vol-%. In neun Fachvortraegen und einer ausfuehrlichen Diskussionsrunde, die in dem vorliegenden Tagungsband wiedergegeben sind, wurden Messdaten zur Konzentration von MTBE in Luft, Niederschlag, Oberflaechen- und Grundwasser vorgestellt und die Moeglichkeiten einer Modellbildung eroertert. Die Teilnehmer des Fachgespraechs waren sich einig, dass die derzeitige Datenlage und die Kenntnisse zum Vorkommen und zu den Verbreitungswegen von MTBE in den Umweltmedien keinesfalls geeignet sind, abschliessend Entwarnung zu geben und eine Grundwassergefaehrdung durch MTBE auszuschliessen. (orig.)

  3. Low-cost development of the Algyoefield in Hungary by means of horizontal re-entry boreholes; Die kostenguenstige Entwicklung des Algyoe-West-Feldes in Ungarn durch horizontale Re-Entry-Bohrungen

    Energy Technology Data Exchange (ETDEWEB)

    Kinzel, H. [Weatherford Oil Tool GmbH, Langenhagen (Germany); Osz, A. [Magyar Olaj (MOL), Budapest (Hungary); Kerk, T. [Becfield Drilling Services, Edemissen-Berkhoepen (Germany)

    1998-12-31

    Planning and implementation of a typical re-entry borehole in southern Hungary are described. The cost is about half that of a new borehole, and the available infrastructure can be used. The production index of a typical Algyoehorizontal borehole is higher by a factor of 12 than for a vertical borehole in the same field. (orig.) [Deutsch] Anhand einer Beispielbohrung (Algyoe488) wird die Planung und Durchfuehrung einer typischen Re-Entry Bohrung in Suedungarn beschrieben. Durch die weitgehende Verwendung von standardisierten Komponenten und Verfahren sowie durch die enge Zusammenarbeit zweier deutscher Service Unternehmen mit dem Auftraggeber wurde bei insgesamt 35 Horizontalbohrungen in Ungarn der Effekt der Lernkurve zur optimierten Erstellung der Bohrung und damit zur Kostensenkung effektiv eingesetzt. Die so aufgearbeiteten Bohrungen werden im Vergleich zu einer neuen Bohrung fuer etwa die Haelfte der Kosten erstellt. Die vorhandene Infrastruktur des Feldes kann weiter verwendet werden. Der Produktionsindex einer typischen AlgyoeHorizontalbohrung liegt um den Faktor 12 hoeher als eine Vertikalbohrung im gleichen Feld. (orig.)

  4. Selective oxidation

    International Nuclear Information System (INIS)

    Cortes Henao, Luis F.; Castro F, Carlos A.

    2000-01-01

    It is presented a revision and discussion about the characteristics and factors that relate activity and selectivity in the catalytic and not catalytic partial oxidation of methane and the effect of variables as the temperature, pressure and others in the methane conversion to methanol. It thinks about the zeolites use modified for the catalytic oxidation of natural gas

  5. Attempted treatment of meningeosis leucaemica by intrathecal application of 90-silicate and 90Y-citrate colloid in a case of chronic myleoic leukaemia; Behandlungsversuch einer Meningeosis leucaemica durch intrathekale Applikation von {sup 90}Y-Silikat- und {sup 90}Y-Zitrat-Kolloid bei chronisch-myleoischer Leukaemie

    Energy Technology Data Exchange (ETDEWEB)

    Kittner, C.; Schuemichen, C. [Rostock Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Steiner, B.; Kahl, C.; Wolff, D.; Freund, M. [Rostock Univ. (Germany). Klinik fuer Innere Medizin, Abt. fuer Haematologie; Putzar, H.; Roesler, K.; Hauenstein, K.H. [Rostock Univ. (Germany). Inst. fuer Diagnostische und Interventionalle Radiologie

    2003-12-01

    A 41-year-old man with chronic myeoloic leukaemia was treated for Meningeosis leucaemica by intrathecal application of yttrium-90-citrate colloide as palliative therapy. (orig.) [German] Wir berichten ueber einen 41-jaehrigen Mann mit chronisch-myeloischer Leukaemie bei dem eine Meningeosis leucaemica durch eine intrathekale Applikation von Yttrium-90-Zitrat-Kolloid palliativ therapiert wurde. (orig.)

  6. Anodic oxidation

    CERN Document Server

    Ross, Sidney D; Rudd, Eric J; Blomquist, Alfred T; Wasserman, Harry H

    2013-01-01

    Anodic Oxidation covers the application of the concept, principles, and methods of electrochemistry to organic reactions. This book is composed of two parts encompassing 12 chapters that consider the mechanism of anodic oxidation. Part I surveys the theory and methods of electrochemistry as applied to organic reactions. These parts also present the mathematical equations to describe the kinetics of electrode reactions using both polarographic and steady-state conditions. Part II examines the anodic oxidation of organic substrates by the functional group initially attacked. This part particular

  7. Energy conservation in refrigerating machines by combining of thermo-static expansion valve and interior heat transfer material; Energieeinsparung in Kaelteanlagen durch Kombination von thermostatischem Expansionsventil und innerem Waermeuebertrager

    Energy Technology Data Exchange (ETDEWEB)

    Tambovtsev, Alexander

    2007-12-15

    bekannten Komponenten TEV und IWUeals inkompatibel miteinander, weil die einfache Aneinanderreihung zu einem instabilen Regelverhalten fuehrt. Nach detaillierter Analyse der Ursachen dieser Instabilitaet wird die Hypothese aufgestellt, dass durch eine absichtliche ''Verschlechterung'' des IWUeein stabiler Arbeitsbereich gefunden werden kann. Bei dieser ''Verschlechterung'' kann es sich z. B. um den Bypass eines Teils des Hochdruckstromes oder um eine Gleichstromanordnung der Stroeme im Waermeuebertrager handeln. Diese Hypothese wurde primaer durch Experimente, aber zusaetzlich auch durch Simulationsrechnungen bestaetigt. Dafuer wurde ein Versuchsstand aufgebaut, mit welchem verschiedene Konfigurationen und Regelstrategien getestet wurden. Es wurde eine deutliche Verringerung des Energieverbrauchs gegenueber herkoemmlichen Anordnungen erreicht. (orig.)

  8. Measurements of size distributions of radon progeny for improved quantification of the lung cancer risk emanating from exposure to radon decay products; Messungen der Groessenverteilungen von Radon-Folgeprodukten zur Verbesserung der Quantifizierung des durch Radonexposition verursachten Lungenkrebsrisikos

    Energy Technology Data Exchange (ETDEWEB)

    Haninger, T

    1998-12-31

    A major issue in radiation protection is to protect the population from the harmful effects of exposure to radon and radon progeny. Quantification of the lung cancer risk emanating from exposure to radon decay products in residential and working environments poses problems, as epidemiologic studies yield information deviating from the results obtained by the indirect method of assessment based on dosimetric respiratory tract models. One important task of the publication here was to characterize the various exposure conditions and to quantify uncertainties that may result from application of the ``dose conversion convention``. A special aerosol spectrometer was therefore designed and built in order to measure the size distributions of the short-lived radon decay products in the range between 0.5 nm and 10 000 nm. The aerosol spectrometer consists of a three-step diffusion battery with wire nets, an 11-step BERNER impactor, and a detector system with twelve large-surface proportional detectors. From the measured size distributions, dose conversion coefficients, E/P{sup eq}, were calculated using the PC software RADEP; the RADEP program was developed by BIRCHALL and JAMES and is based on the respiratory tract model of the ICRP. The E/P{sup eq} coefficients indicate the effective dose E per unit exposure P{sup eq} to radon decay products. (orig./CB) [Deutsch] Eines der groessten Probleme des Strahlenschutzes ist der Schutz der Bevoelkerung vor einer Strahlenexposition durch Radon und seine Folgeprodukte. Die Quantifizierung des Lungenkrebsrisikos, das durch Radonexpositionen in Wohnungen und an Arbeitsplaetzen verursacht wird, ist ein grosses Problem, weil epidemiologische Studien ein anderes Ergebnis liefern, als die indirekte Methode der Abschaetzung mit dosimetrischen Atemtrakt-Modellen. Eine wichtige Aufgabe der vorliegenden Arbeit war es, unterschiedliche Expositionsbedingungen zu charakterisieren und die Unsicherheiten zu quantifizieren, die sich aus der

  9. Racism, Ethnicity and the Media in Africa: Reflections Inspired by Studies of Xenophobia in Cameroon and South Africa Rassismus, Ethnizität und die Medien in Afrika: Reflektionen angeregt durch Studien zu Fremdenfeindlichkeit in Kamerun und Südafrika

    Directory of Open Access Journals (Sweden)

    Francis B. Nyamnjoh

    2010-01-01

    Full Text Available This paper demonstrates the extent to which the media and belonging in Africa are torn between competing and often conflicting claims of bounded and flexible ideas of culture and identity. It draws on studies of xenophobia in Cameroon and South Africa, inspired by the resilience of the politicization of culture and identity, to discuss the hierarchies and inequalities that underpin political, economic and social citizenship in Africa and the world over, and the role of the media in the production, enforcement and contestation of these hierarchies and inequalities. In any country with liberal democratic aspirations or pretensions, the media are expected to promote national citizenship and its emphasis on large-scale, assimilationist and territorially bounded belonging, while turning a blind eye to those who fall through the cracks as a result of racism and/or ethnicity. Little wonder that such an exclusionary articulation of citizenship is facing formidable challenges from its inherent contradictions and closures, and from an upsurge in the politics of recognition and representation by small-scale communities claiming autochthony at a historical juncture where the rhetoric espouses flexible mobility, postmodern flux and discontinuity. Der vorliegende Beitrag zeigt auf, inwieweit die Medien und gesellschaftliche Bindungen in Afrika zwischen konfligierenden Ansprüchen abgegrenzter und sich wandelnder kultureller Identitäten zerrissen sind. Angeregt durch die Erfahrung der kontinuierlichen Politisierung kultureller und sozialer Identitäten zieht der Autor Studien zu Fremdenfeindlichkeit in Kamerun und Südafrika heran, um die Hierarchien und Ungleichheiten zu diskutieren, auf denen politische, wirtschaftliche und soziale Staatsbürgerschaft in Afrika und darüber hinaus basiert, sowie die Rolle der Medien bei der Entstehung, Verstärkung und im Wettstreit dieser Hierarchien und Ungleichheiten. In jedem liberal-demokratisch ausgerichteten Staat

  10. Measurements of size distributions of radon progeny for improved quantification of the lung cancer risk emanating from exposure to radon decay products; Messungen der Groessenverteilungen von Radon-Folgeprodukten zur Verbesserung der Quantifizierung des durch Radonexposition verursachten Lungenkrebsrisikos

    Energy Technology Data Exchange (ETDEWEB)

    Haninger, T.

    1997-12-31

    A major issue in radiation protection is to protect the population from the harmful effects of exposure to radon and radon progeny. Quantification of the lung cancer risk emanating from exposure to radon decay products in residential and working environments poses problems, as epidemiologic studies yield information deviating from the results obtained by the indirect method of assessment based on dosimetric respiratory tract models. One important task of the publication here was to characterize the various exposure conditions and to quantify uncertainties that may result from application of the ``dose conversion convention``. A special aerosol spectrometer was therefore designed and built in order to measure the size distributions of the short-lived radon decay products in the range between 0.5 nm and 10 000 nm. The aerosol spectrometer consists of a three-step diffusion battery with wire nets, an 11-step BERNER impactor, and a detector system with twelve large-surface proportional detectors. From the measured size distributions, dose conversion coefficients, E/P{sup eq}, were calculated using the PC software RADEP; the RADEP program was developed by BIRCHALL and JAMES and is based on the respiratory tract model of the ICRP. The E/P{sup eq} coefficients indicate the effective dose E per unit exposure P{sup eq} to radon decay products. (orig./CB) [Deutsch] Eines der groessten Probleme des Strahlenschutzes ist der Schutz der Bevoelkerung vor einer Strahlenexposition durch Radon und seine Folgeprodukte. Die Quantifizierung des Lungenkrebsrisikos, das durch Radonexpositionen in Wohnungen und an Arbeitsplaetzen verursacht wird, ist ein grosses Problem, weil epidemiologische Studien ein anderes Ergebnis liefern, als die indirekte Methode der Abschaetzung mit dosimetrischen Atemtrakt-Modellen. Eine wichtige Aufgabe der vorliegenden Arbeit war es, unterschiedliche Expositionsbedingungen zu charakterisieren und die Unsicherheiten zu quantifizieren, die sich aus der

  11. Magnesium Oxide

    Science.gov (United States)

    Magnesium is an element your body needs to function normally. Magnesium oxide may be used for different reasons. Some people use it as ... one to four times daily depending on which brand is used and what condition you have. Follow ...

  12. Rezension von: Ulf Gebken, Söhnke Vosgerau (Hg.: Fußball ohne Abseits. Ergebnisse und Perspektiven des Projekts ‚Soziale Integration von Mädchen durch Fußball‘. Wiesbaden: Springer VS 2014.

    Directory of Open Access Journals (Sweden)

    Robert Claus

    2014-12-01

    Full Text Available Seit 2006 wurden im Rahmen des vom Deutschen Fußball-Bund durchgeführten Modellprojektes „Soziale Integration von Mädchen durch Fußball“ an über 200 Standorten Schul-AGs in sogenannten Brennpunktbezirken aufgebaut. Im vorliegenden Sammelband beleuchten die Autor/-innen ausführlich die Funktion von Sport für die pädagogische Kompetenzvermittlung. Zudem erbringen sie einen umfassenden Projektbericht und leisten ein Plädoyer für die Modernisierung des Verhältnisses zwischen Schule und Vereinen, Lehrplan und Ehrenamt. Somit stellt das Buch, wie auch das Projekt, einen enorm wichtigen Beitrag zur Geschlechtergerechtigkeit im Sport dar. Gleichzeitig jedoch liest sich eine Reihe an Texten etwas zu sperrig für den Bericht einer Praxisforschung, und Begriffe im Feld der ‚Integration’ bleiben schwammig.

  13. Superconductors for the medium-voltage grid. A superconducting power cable running through the inner city of Essen passes a two-year field test; Supraleiter fuer das Mittelspannungsnetz. Ein supraleitendes Stromkabel quer durch die Essener Innenstadt besteht zweijaehrigen Feldtest

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Franz

    2017-04-01

    Scientists are testing the longest high-temperature superconducting cable in the world under real conditions in Essen. One kilometre long, it connects two substations in the inner city. It replaces a conventional 110 kV line and renders one substation in the inner city obsolete. After two years of testing, it has passed the field test. It could be a blueprint for the future power supply system in urban areas. [German] Wissenschaftler testen in Essen das laengste Hochtemperatur-Supraleiterkabel der Welt unter realen Bedingungen. Mit einer Laenge von einem Kilometer verbindet es zwei Umspannstationen quer durch die Innenstadt. Es ersetzt eine konventionelle 110-kV-Leitung und macht eine Umspannanlage im Stadtzentrum ueberfluessig. In einer zweijaehrigen Erprobung hat es den Praxistest bestanden. Es koennte eine Blaupause fuer die kuenftige Stromversorgung in Ballungsraeumen sein.

  14. Tests in excess sludge minimization through cell membrane break-up by means of ozone at a municipal sewage treatment plant; Versuche zur Ueberschussschlamm-Minimierung durch Zellaufschluss mit Ozon auf einer kommunalen Klaeranlage

    Energy Technology Data Exchange (ETDEWEB)

    Ried, A.; Peters, B. [WEDECO Umweltdienstleistungen GmbH, Herford (Germany)

    1999-07-01

    Disposing of sewage sludge involves high cost. Therfore, processes to reduce sewage sludge are more and more in demand. One such process is the treatment with ozone. The company WEDESCO GmbH is also concerned with ozonification of sewage sludge and carries out tests on a technical scale at a municipal sewage treatment plant. The objective is to reduce the amount of sewage sludge by approximately 50 %, corresponding, in the present case, to the organic sludge portion. (orig.) [German] Da die Entsorgung dieses Klaerschlamms hohe Kosten verursacht, gewinnen Verfahren zur Klaerschlammreduzierung zunehmend an Bedeutung. Eine Moeglichkeit der Reduzierung des Klaerschlamms besteht in der Behandlung mit Ozon. Auch die WEDECO GmbH befasst sich mit der Ozonung von Klaerschlamm und fuehrt Versuche im grosstechnischen Massstab auf einer kommunalen Klaeranlage durch. Ziel dieser Versuche ist es, den anfallenden Klaerschlamm um ca. 50% zu reduzieren, was in diesem Anwendungsfall dem organischen Anteil des Schlamms entspricht. (orig.)

  15. Water pollution potential of mineral oils with high content of polycyclic aromatic hydrocarbons (heavy fuel oil and neutral oil extracts); Untersuchungen zur Wassergefaehrdung durch Mineraloele mit hohen Gehalten an polycyclischen aromatischen Kohlenwasserstoffen (Heizoel Schwer und Extrakte)

    Energy Technology Data Exchange (ETDEWEB)

    Albers, G. [Mobil Schmierstoff GmbH, Hamburg (Germany)

    1999-01-01

    A data base on highly aromatic mineral oils has been compiled to classify mineral oil products according to their water-pollution potential (water hazard class or Wassergefaehrdungsklasse, WGK). This activity has been undertaken through the Commission for Water Hazardous Materials (Kommission Bewertung Wassergefaehrdender Stoffe, KBwS). In this special case, highly aromatic mineral oils containing a high concentration of polycyclic aromatic hydrocarbons (Polyaromatische Kohlenwasserstoffe, PAK) were evaluated. A test method for measuring the elution potential of PAK into water was developed on petroleum products with high viscosity and high freeze point. This method was applied to determine the solubility of 23 PAK (including 16 PAK according to EPA 610 and 6 PAK according to the German drinking water regulation (Trinkwasserverordnung, TVO)) from heavy fuel oil and neutral oil extract in the aqueous phase. For the 6 PAK, according to TVO, a sum limit of 0,2 {mu}g/l in drinking water is permitted by German legislation. This limit was not exceeded in any of the water phases examined. (orig.) [Deutsch] Fuer die Einstufung von Mineraloelprodukten in die Wassergefaehrdungsklassen (WGK) durch die Kommission Bewertung Wassergefaehrdender Stoffe ist es notwendig, Basisdaten zur Verfuegung zu stellen. Im speziellen Fall handelt es sich um die Bewertung von Mineraloelen, die sich durch einen hohen Gehalt an polycyclischen aromatischen Kohlenwasserstoffen (PAK) auszeichnen. Zur Eluierbarkeit von PAK`s aus Produkten mit hoher Viskosiaet bzw. mit hohem Stockpunkt wurde eine Pruefmethode entwickelt. Diese Methode wurde zur Bestimmung der Loeslichkeit von 23 PAK`s (16 PAK`s nach EPA-Liste incl. 6 PAK`s der TVO) aus den Mineraloelen Heizoel Schwer und Neutralextrakt in der Wasserphase eingesetzt. Fuer die PAK der TVO ist in der TVO ein Summengrenzwert von 0,2 {mu}g/l Trinkwasser angegeben. Dieser Grenzwert wurde in keiner der untersuchten Wasserphasen ueberschritten. (orig.)

  16. Oxidative stress

    Directory of Open Access Journals (Sweden)

    Osredkar Joško

    2012-05-01

    Full Text Available The human organism is exposed to the influence of various forms of stress, either physical, psychological or chemical, which all have in common that they may adversely affect our body. A certain amount of stress is always present and somehow directs, promotes or inhibits the functioning of the human body. Unfortunately, we are now too many and too often exposed to excessive stress, which certainly has adverse consequences. This is especially true for a particular type of stress, called oxidative stress. All aerobic organisms are exposed to this type of stress because they produce energy by using oxygen. For this type of stress you could say that it is rather imperceptibly involved in our lives, as it becomes apparent only at the outbreak of certain diseases. Today we are well aware of the adverse impact of radicals, whose surplus is the main cause of oxidative stress. However, the key problem remains the detection of oxidative stress, which would allow us to undertake timely action and prevent outbreak of many diseases of our time. There are many factors that promote oxidative stress, among them are certainly a fast lifestyle and environmental pollution. The increase in oxidative stress can also trigger intense physical activity that is directly associated with an increased oxygen consumption and the resulting formation of free radicals. Considering generally positive attitude to physical activity, this fact may seem at first glance contradictory, but the finding has been confimed by several studies in active athletes. Training of a top athlete daily demands great physical effort, which is also reflected in the oxidative state of the organism. However, it should be noted that the top athletes in comparison with normal individuals have a different defense system, which can counteract the negative effects of oxidative stress. Quite the opposite is true for irregular or excessive physical activity to which the body is not adapted.

  17. Oxidation catalyst

    Science.gov (United States)

    Ceyer, Sylvia T.; Lahr, David L.

    2010-11-09

    The present invention generally relates to catalyst systems and methods for oxidation of carbon monoxide. The invention involves catalyst compositions which may be advantageously altered by, for example, modification of the catalyst surface to enhance catalyst performance. Catalyst systems of the present invention may be capable of performing the oxidation of carbon monoxide at relatively lower temperatures (e.g., 200 K and below) and at relatively higher reaction rates than known catalysts. Additionally, catalyst systems disclosed herein may be substantially lower in cost than current commercial catalysts. Such catalyst systems may be useful in, for example, catalytic converters, fuel cells, sensors, and the like.

  18. RNA oxidation

    DEFF Research Database (Denmark)

    Kjaer, L. K.; Cejvanovic, V.; Henriken, T.

    2015-01-01

    .9 significant hazard ratio for death compared with the quartile with the lowest 8oxoGuo excretion when adjusted for age, sex, BMI, smoker status, s-HbA1c, urine protein excretion and s-cholesterol. We conclude that it is now established that RNA oxidation is an independent risk factor for death in type 2...

  19. Radiolytic oxidation

    International Nuclear Information System (INIS)

    Burns, W.G.; Ewart, F.T.; Hobley, J.; Smith, A.J.; Walters, W.S.; Williams, S.J.

    1991-01-01

    Work under the Radiolytic Oxidation Contract from 1986 until April 1989 is reported. The effects of alpha- and gamma-irradiation on the chemistries of plutonium, neptunium and technetium, under conditions representative of the near fields of intermediate and high level waste repositories, were investigated. Gamma-radiolysis of Np (IV) results in oxidation in solutions below pH 12. Solutions of Tc (VII) are reduced to Tc (IV) by gamma-irradiation in contact with blast furnace slag/ordinary Portland cement under an inert atmosphere but not when in contact with pulverized fuel ash/ordinary Portland cement. Tc (IV) is shown to be susceptible to oxidation by the products of the alpha-radiolysis of water. The results of 'overall effects' experiments, which combined representative components of typical ILW or HLW near fields, supported these observations and also showed enhanced plutonium concentrations in alpha-irradiated, HLW simulations. Mathematical models of the behaviour of plutonium and neptunium during gamma-radiolysis have been developed and indicate that oxidation to Pu (VI) is possible at dose rates typical of those expected for HLW. Simulations at ILW dose rates have indicated some effect upon the speciation of neptunium. Laboratory studies of the gamma-irradiation of Np (IV) in bentonite-equilibrated water have also been modelled. Computer code used: PHREEQE, 8 Figs.; 48 Tabs.; 38 refs

  20. Oxidative stress

    Directory of Open Access Journals (Sweden)

    Stevanović Jelka

    2012-01-01

    Full Text Available The unceasing need for oxygen is in contradiction to the fact that it is in fact toxic to mammals. Namely, its monovalent reduction can have as a consequence the production of short-living, chemically very active free radicals and certain non-radical agents (nitrogen-oxide, superoxide-anion-radicals, hydroxyl radicals, peroxyl radicals, singlet oxygen, peroxynitrite, hydrogen peroxide, hypochlorous acid, and others. There is no doubt that they have numerous positive roles, but when their production is stepped up to such an extent that the organism cannot eliminate them with its antioxidants (superoxide-dismutase, glutathione-peroxidase, catalase, transferrin, ceruloplasmin, reduced glutathion, and others, a series of disorders is developed that are jointly called „oxidative stress.“ The reactive oxygen species which characterize oxidative stress are capable of attacking all main classes of biological macromolecules, actually proteins, DNA and RNA molecules, and in particular lipids. The free radicals influence lipid peroxidation in cellular membranes, oxidative damage to DNA and RNA molecules, the development of genetic mutations, fragmentation, and the altered function of various protein molecules. All of this results in the following consequences: disrupted permeability of cellular membranes, disrupted cellular signalization and ion homeostasis, reduced or loss of function of damaged proteins, and similar. That is why the free radicals that are released during oxidative stress are considered pathogenic agents of numerous diseases and ageing. The type of damage that will occur, and when it will take place, depends on the nature of the free radicals, their site of action and their source. [Projekat Ministarstva nauke Republike Srbije, br. 173034, br. 175061 i br. 31085

  1. Radiation exposure to the patient caused by single-photon transmission measurement for 3D whole-body PET; Die Strahlenexposition des Patienten durch die Einzelphotonen-Transmissionsmessung bei der PET

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, A.; Donsch, P.; Kirsch, C.M. [Universitaet des Saarlandes, Homburg/Saar (Germany). Abt. fuer Nuklearmedizin; Seifert, H. [Universitaet des Saarlandes, Homburg/Saar (Germany). Abt. Strahlentherapie der Radiologischen Klinik

    2000-11-01

    Patienten durch die Transmissionsmessung mittels Einzelphotonenquellen bei der PET. Material und Methode: Zwei Cs-137-Punktquellen (E{gamma}=662 keV, A=614 MBq) werden zur Transmissionsmessung im Einzelphotonenmodus an einem 3D-Scanner (ECAT ART) eingesetzt. Bei der Simulation einer Ganzkoerper-Transmission (axiale Laenge: 75 cm, 6 ueberlappende Bettpositionen), werden Dosismessungen mit Thermolumineszenzdosimetern unter Verwendung eines Thorax- und eines Abdomenphantoms durchgefuehrt. Aus den Messwerten wurde in Anlehnung an den Report Nr. 60 der ICRP die effektive Dosis fuer die Transmissionsmessung abgeschaetzt. Ergebnisse: Bei einer Gesamtaufnahmedauer von 360 min (60 min pro Bettposition) ergaben sich folgende Energiedosen: Oberflaeche (Xyphoid) 189 {mu}Gy, Herz 196 {mu}Gy, Lunge 234 {mu}Gy, BWS 240 {mu}Gy, Niere 207 {mu}Gy, Leber 204 {mu}Gy, Gonaden 205 {mu}Gy, Schilddruese 249 {mu}Gy und Blase 185 {mu}Gy, aus denen sich ein Konversionsfaktor von 1,7*10{sup -4} mSv/(h*MBq) errechnete. Die Abschaetzung der effektiven Dosis fuer den Patienten aufgrund einer Transmissionsmessung (Akquisitionszeit von 3,2 min pro Bettposition) ergab einen Wert von 11 {mu}Sv. Die Abschaetzung des Verhaeltnisses der Konversionsfaktoren durch Transmissionsmessung im Einzelphotonen- und im Koinzidenzmodus (zwei Ge-68/Ga-68-Linienquellen mit jeweils 40 MBq) ergab einen Wert von 0,18. Der Vergleich zwischen den effektiven Dosen durch die Transmission im Einzelphotonen-Modus und die Emission (bei Injektion von 250 MBq FDG) ergab ein Verhaeltnis von 2,3*10{sup -3}. Schlussfolgerung: Die Strahlenexposition der Patienten durch die Transmissionsmessung in der 3D-PET ist vernachlaessigbar gering. Sie wird durch die Verwendung der Einzelphotonenmethode mit kollimierten Punktquellen relativ hoher Aktivitaet im Vergleich zur Koinzidenzmethode mit nicht-kollimierten Linienquellen relativ niedriger Aktivitaet weiter reduziert. (orig.)

  2. Improved patient repositioning accuracy by integrating an additional jaw fixation into a high precision face mask system in stereotactic radiotherapy of the head; Verbesserte lagerungsreproduzierbarkeit eines nichtinvasiven hochpraezisionsmaskensystems in der stereotaktischen Radiotherapie durch eine integrierte kieferfixierung

    Energy Technology Data Exchange (ETDEWEB)

    Lopatta, E.; Liesenfeld, S.M.; Bank, P.; Guenther, R.; Wiezorek, T.; Wendt, T.G. [Klinik fuer Radiologie, Abt. fuer Strahlentherapie, Friedrich-Schiller-Univ. Jena (Germany); Wurm, R. [Campus Charite Mitte, Klinik fuer Strahlentherapie, Berlin (Germany)

    2003-08-01

    Strahlentherapie. Material und Methoden: 29 Patienten wurden unter stereotaktischen Bedingungen fraktioniert bestrahlt. Jeder Patient erhielt das individuell angepasste Zwei-Halbschalen-Maskensystem (BrainLab trademark). Bei 18 dieser Patienten kam eine zusaetzliche Kieferfixierung entweder als Oberkieferfixierung (OKF) oder als zusaetzliche Unterkieferfixierung (UKF) zum Einsatz. Die Reproduzierbarkeit der Lagerung wurde durch Ausmessung von Verschiebungen anatomischer Strukturen auf Filmebene in 0 und 90 bestimmt. Vor den Aufnahmen in Gantryposition 0 und 90 erfolgte die Feinjustierung des Simulators ueber ein optisches Ringsystem. Insgesamt wurden waehrend der 2- bis 7-woechigen Therapie 844 Messungen an einem digitalen Bildverarbeitungssystem erhoben. Ergebnisse: Im Vergleich der Standardabweichungen der Messergebnisse ergibt sich unter Verwendung einer zusaetzlichen Kieferfixierung eine signifikante Verbesserung der Lagerungsreproduzierbarkeit in den drei Freiheitsgraden: Lateralverschiebung 0,6 mm mit Kieferfixierung vs. 0,7 mm ohne Fixierung (p < 0,001); Longitudinalverschiebung in 0 Aufnahme gemessen 0,5 vs. 1,3 mm (p < 0,001), Longitudinalverschiebung in 90 -Aufnahme gemessen 0,5 mm vs. 1,5 mm (p < 0,001), Vertikalverschiebung 0,6 vs. 0,9 mm (p = 0,001). Kein signifikanter Unterschied der Abweichungen ergibt sich im Vergleich zwischen OKF und UKF. Schlussfolgerung: Diese Untersuchung konnte eine signifikante Verbesserung der Lagerungspraezision durch die Verwendung einer zusaetzlichen, individuell geformten Kieferfixierung mit dem BrainLab trademark -Maskensystem nachweisen. Die Lagerungsvariabilitaet betraegt in allen Richtungen weniger als 2 mm. Somit kann der Sicherheitssaum um das klinische Zielvolumen insbesondere bei benignen Tumoren durch verbesserte Fixierung entscheidend verkleinert werden. (orig.)

  3. Prise en charge des complications de la chirurgie partielle du larynx ...

    African Journals Online (AJOL)

    Smoking is the main risk factor especially if associated with chronic alcoholism. ... of the tumor in a very limited rigid tube and to a well-codified surgical treatment. ... emphysema (7.4%), salivary fistula (1 case) and acute pancreatitis (1 case).

  4. Capacités calorifiques apparente et partielle des alcanoates de ...

    African Journals Online (AJOL)

    AKA Boko

    Figure 3 : Variation de log (cmc) en fonction du nombre d'atome de carbones de la chaîne hydrophobe des alcanoates de sodium. 3-2. Capacités calorifiques molaires apparentes. Les courbes. ) ( 2/1 mf cp. =Φ. (Figures 1 et 2) évoluent avec la longueur de la chaîne hydrophobe. Aux concentrations en dessous de la cmc, ...

  5. Exhaust purification of DI spark ignition engines by means of barrier discharge. Final report; Abgasreinigung von DI-Ottomotoren durch Barrierenentladungen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Wolters, P.; Lepperhoff, G.; Baumgarten, H.; Scharr, D.; Neff, W.; Trompeter, F.J.; Seiwert, S.; Kamp, J.; Pochner, K.

    2000-07-01

    Dielectric barrier discharge offers the advantage to excite and dissociate molecules in the exhaust gas stream. Those dissociated and excited species are oxidizing or reducing harmful exhaust gas components. The advantage of a plasma chemical system in comparison to a catalytic converter is the instantaneous activity at ambient temperature from the turn key of the engine. The investigations presented here focus on the plasma chemical oxidation of hydrocarbons in the exhaust gas stream during cold start conditions. The article concerns the design and development of a plasma system in order to decrease the hydrocarbon emissions from engine start till catalyst light off. Vehicle results in the new European driving cycle show a hydrocarbon conversion of more than 43% in the first 11 seconds from engine start. In this period nearly all types of hydrocarbon were reduced. The exhaust back pressure of the sytem is comparable to the conventional muffler. Further system improvement can be achieved by an optimization of the disk electrode design. [German] Um die strengen zukuenftigen Schadstoffemissionsgrenzwerte von Ottomotoren in der EU oder den USA einhalten zu koennen, werden derzeit weltweit auch plasmachemische Methoden zur Abgasnachbehandlung in Betracht gezogen. Insbesondere nichtthermische Atmosphaerendruck-Gasentladungen, wie die Barrierenentladung, zeigen Chancen auf, die Betriebsbedingungen und Grenzen gegenwaertiger katalytischer Techniken zu erweitern. In diesem Vorhaben wurde die Barrierenentladung zur plasmachemischen Umsetzung von Schadstoffen im Abgas eines mager betriebenen Ottomotors im Serienautomobil untersucht, um das Potential zur Abgasreinigung zu bewerten und auszuweiten. (orig.)

  6. PREFACE: Semiconducting oxides Semiconducting oxides

    Science.gov (United States)

    Catlow, Richard; Walsh, Aron

    2011-08-01

    Semiconducting oxides are amongst the most widely studied and topical materials in contemporary condensed matter science, with interest being driven both by the fundamental challenges posed by their electronic and magnetic structures and properties, and by the wide range of applications, including those in catalysis and electronic devices. This special section aims to highlight recent developments in the physics of these materials, and to show the link between developing fundamental understanding and key application areas of oxide semiconductors. Several aspects of the physics of this wide and expanding range of materials are explored in this special section. Transparent semiconducting oxides have a growing role in several technologies, but challenges remain in understanding their electronic structure and the physics of charge carriers. A related problem concerns the nature of redox processes and the reactions which interconvert defects and charge carriers—a key issue which may limit the extent to which doping strategies may be used to alter electronic properties. The magnetic structures of the materials pose several challenges, while surface structures and properties are vital in controlling catalytic properties, including photochemical processes. The field profits from and exploits a wide range of contemporary physical techniques—both experimental and theoretical. Indeed, the interplay between experiment and computation is a key aspect of contemporary work. A number of articles describe applications of computational methods whose use, especially in modelling properties of defects in these materials, has a long and successful history. Several papers in this special section relate to work presented at a symposium within the European Materials Research Society (EMRS) meeting held in Warsaw in September 2010, and we are grateful to the EMRS for supporting this symposium. We would also like to thank the editorial staff of Journal of Physics: Condensed Matter for

  7. The production of wear protection coatings reinforced with tungsten carbide by temperature-controlled welding with the CO{sub 2} laser; Herstellung wolframkarbidverstaerkter Verschleissschutzschichten durch temperaturgeregeltes Auftragschweissen mit dem CO{sub 2}-Laser

    Energy Technology Data Exchange (ETDEWEB)

    Nowotny, S.; Boddin, G.C.; Luft, A.; Techel, A. [Fraunhofer-Inst. fuer Werkstoffphysik und Schichttechnologie, Dresden (Germany); Uelze, A. [Hochschule fuer Technik und Wirtschaft Dresden (Germany)

    1995-12-31

    Protective coatings can be produced by laser coating with metal alloys reinforced by carbide, whose resistance to abrasive wear with a content of 40 to 50% by volume of hard material is comparable to sintered TC-Co hard metal. Due to the remaining ductile material behaviour and the metallurgical binding to the substrate, the coatings have high impact, fatigue and adhesion strengths. The use of process control leads to a stable coating process and to increased safety and reproduceability when working in narrow parameter areas. (orig./RHM) [Deutsch] Durch das Laserbeschichten mit karbidverstaerkten Metallegierungen koennen Schutzschichten erzeugt werden, deren Widerstand gegen Abrasivverschleiss bereits bei einem Hartstoff-Volumengehalt von 40 bis 50% gesintertem WC-Co-Hartmetall vergleichbar ist. Aufgrund des verbleibenden duktilen Werkstoffverhaltens und der metallurgischen Bindung zum Substrat verfuegen die Schichten ueber hohe Schlag-, Ermuedungs- und Haftfestigkeiten. Der Einsatz der Prozessregelung fuehrt zu einem stabilen Beschichtungsvorgang und zu einer erhoehten Sicherheit und Reproduzierbarkeit beim Arbeiten in eng begrenzten Parameterbereichen. (orig./RHM)

  8. New epoxide polymers generated by metal organic catalysts (chelates) and their application in composite structures. Pt. 2. Final report; Neue Epoxidpolymere durch Metallorgano-Katalysatoren und ihr Einsatz in Faserverbundstrukturen. T. 2. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Merz, T.; Raeckers, B.

    1999-08-01

    Epoxy resins cured by catalysts based on chelate compound can offer an additional potential concerning storage and heat stability, toughness and curing characteristic. To prove these advantages and to prepare a serial application was target of the project, by which physico-chemical investigations, determination of mechanical properties and component tests were used. Besides an improvement of storage time and a minimized curing cycle a satisfactory processing behaviour and mechanical properties approaching currently used aircraft materials became evident. Serial production of fibre reinforced components for automotive industry is basically possible, because all requirements concerning costs, performance and station time were met. The results can also be used for new applications in other technical fields like apparatus construction or sporting goods industry. (orig.) [German] Mittels Metallorganokatalysatoren gehaertete Epoxidharze versprechen gegenueber herkoemmlichen Systemen zusaetzliche Potentiale hinsichtlich Lager- und Waermestabilitaet sowie Zaehigkeit und Haertungscharakteristik. Diese nachzuweisen und eine zukuenftige Serienanwendung vorzubereiten war Ziel des Projektes, wozu physico-chemische Untersuchungen, mechanische Kennwertermittlungen und Bauteilversuche dienten. Neben verbesserter Lagerstabilitaet und minimierten Haertungszyklen konnten gute Verarbeitungseingeschaften und ein Leistungsprofil nachgewiesen werden, das nahe an das heutiger Luftfahrtwerkstoffe heranreicht. Die Serienherstellung von Faserverbundbauteilen im Automobilbau ist prinzipiell moeglich, da durch die entwickelten Katalysatoren alle Vorgaben hinsichtlich Kosten, Leistungsfaehigkeit und Taktzeiten erreicht werden konnten. Hierdurch koennen sich auch fuer andere Bereiche (z.B. Geraetebau, Sportartikelindustrie) neue Anwendungsmoeglichkeiten eroeffnen. (orig.)

  9. Enhancing the dewatering properties of sludge through aimed building-up of floc structures on the basis of detailed morphological analyses; Verbesserung der Entwaesserungseigenschaften von Schlaemmen durch den gezielten Aufbau von Flockenstrukturen auf der Basis detaillierter morphologischer Analysen

    Energy Technology Data Exchange (ETDEWEB)

    Nagel, M.; Ay, P. [Brandenburgische Technische Univ. Cottbus (Germany). Lehrstuhl Aufbereitungstechnik

    1999-07-01

    Aimed building-up of aggregates as they originate in flocculation processes, for instance in sewage and sludge treatment, have especially lately been meeting with increasing resonance: they permit to influence, inter alia, important properties (e.g., the dewatering properties) of such systems. As conventional mathematical methods for the characterization of flocs - as a basis for process optimization - are inadequate or flawed, a concept for the effective characterization of the inner getup of such structures needs to be sought. One approach is cluster analysis, which is demonstrated and discussed in the present paper by means of the evaluation of sectional views of floc structures. (orig.) [German] Der gezielte Aufbau von Aggregaten, wie sie bei Flockungsprozessen z.B. in der Abwasser- und Schlammbehandlung entstehen, findet besonders in juengerer Zeit zunehmend Beachtung, da sich damit unter anderem wichtige Eigenschaften (z.B. die Entwaesserungseigenschaften) dieser Systeme beeinflussen lassen. Da herkoemmliche mathematische Methoden zur Charakterisierung von Flocken - als Basis fuer eine Prozessoptimierung - nur unzureichend bzw. fehlerbehaftet sind, ergibt sich daraus die Notwendigkeit, nach einem Konzept zur effektiven Charakterisierung des inneren Aufbaus solcher Strukturen zu suchen. Ein Ansatz ist die Clusteranalyse, die im Beitrag durch die Auswertung von Schnittbildern von Flockenstrukturen vorgestellt und diskutiert wird. (orig.)

  10. New epoxide polymers generated by metal organic catalysts (chelates) and their application in composite structures. Pt. 1. Final report; Neue Epoxidpolymere durch Metallorgano-Katalysatoren und ihr Einsatz in Faserverbundstrukturen. T. 1. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Merz, T.; Raeckers, B.; Boettcher, A.; Haessler, R.; Renner, M.; Schmidtke, K.

    1999-08-01

    Epoxy resins cured by catalysts based on chelate compound can offer an additional potential concerning storage and heat stability, toughness and curing characteristic. To prove these advantages and to prepare a serial application was target of the project, by which physico-chemical investigations, determination of mechanical properties and component tests were used. Besides an improvement of storage time and a minimized curing cycle a satisfactory processing behaviour and mechanical properties approaching currently used aircraft materials became evident. Serial production of fibre reinforced components for automotive industry is basically possible, because all requirements concerning costs, performance and station time were met. The results can also be used for new applications in other technical fields like apparatus construction or sporting goods industry. (orig.) [German] Mittels Metallorganokatalysatoren gehaertete Epoxidharze versprechen gegenueber herkoemmlichen Systemen zusaetzliche Potentiale hinsichtlich Lager- und Waermestabilitaet sowie Zaehigkeit und Haertungscharakteristik. Diese nachzuweisen und eine zukuenftige Serienanwendung vorzubereiten war Ziel des Projektes, wozu physico-chemische Untersuchungen, mechanische Kennwertermittlungen und Bauteilversuche dienten. Neben verbesserter Lagerstabilitaet und minimierten Haertungszyklen konnten gute Verarbeitungseingeschaften und ein Leistungsprofil nachgewiesen werden, das nahe an das heutiger Luftfahrtwerkstoffe heranreicht. Die Serienherstellung von Faserverbundbauteilen im Automobilbau ist prinzipiell moeglich, da durch die entwickelten Katalysatoren alle Vorgaben hinsichtlich Kosten, Leistungsfaehigkeit und Taktzeiten erreicht werden konnten. Hierdurch koennen sich auch fuer andere Bereiche (z.B. Geraetebau, Sportartikelindustrie) neue Anwendungsmoeglichkeiten eroeffnen. (orig.)

  11. Optimisation of the energy potential of low-CO2 gas turbines by using large monocrystal turbine blades. Final report; Optimierung des Energiepotentials fuer CO{sub 2}-arme Gasturbinen durch grosse Einkristall-Turbinenschaufeln. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Grossmann, J.

    2002-07-01

    Apart from the experimental identification and assessment of process characteristics during industrial-scale application of the so-called liquid metal cooling (LPC) process, the project focused on the characterisation of monocrystalline, directionally solidified materials and components. This involved the construction and commissioning of appropriate production and test aggregates, i.e. the LMC casting system and a Laue orientation testing unit, as well as the modification of a vacuum heat treatment furnace to meet the specific requirement of glow annealing of monocrystalline, directionally solidified turbine blades. [German] Das Ziel des Forschungsvorhabens (Laufzeit: 01. Juli 1997 bis 31. Dezember 2001) 'Optimierung des Energiepotentials fuer CO{sub 2}-arme Gasturbinen durch grosse Einkristall-Turbinenschaufeln' lag neben der experimentellen Bestimmung und Bewertung von Verfahrens- und Prozesskennwerten bei der industriellen Umsetzung des sogenannten Liquid-Metal-Cooling-Verfahrens (LMC) in der Eigenschaftscharakterisierung von einkristallin-gerichtet erstarrten Proben und Bauteilen, die mittels dieser neuartigen Giesstechnologie dargestellt wurden. Grundvoraussetzung fuer die umfassende Bearbeitung der o.g. Arbeitsinhalte war die Konstruktion und Inbetriebnahme der notwendigen Fertigungs- und Pruefaggregate, d.h. der LMC-Giessanlage und einer Laue-Orientierungspruefeinrichtung bzw. der Abstimmung eines Vakuum-Waermebehandlungsofens auf die spezifischen Anforderungen der Loesungsgluehung einkristallin-gerichtet erstarrter Turbinenlaufschaufeln. (orig.)

  12. The oxidation; Okislenie

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, V I

    1961-07-01

    In this chapter of book author determine that alkylene tetra hydro-{gamma}-piron, oxidated by potassium permanganate in all cases of passed oxidation gave oxidation products, confirmatory their structure.

  13. Engine 3E. NO{sub x} reduction by means of homogenisation of mixtures inside combustion chambers. Final report; Engine 3E. NO{sub x}-Reduktion durch Homogenisierung des Gemisches in Brennkammern. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Zarzalis, N.; Homann; Schubert

    1999-11-05

    This is the final report of the Technology Project 'NO{sub x} reduction by means of homogenisation of mixtures inside combustion chambers', which is part of the Engine 3E 2010 programme of the BMBF, which was to promote research in aircraft engineering. In this project, technologies were developed to achieve a 60% reduction of NO{sub x} emissions as compared to ICAO '95 in an annular combustion chamber in realistic operating conditions where the emissions of substances oher than NO{sub x} were to be of the same level as the emissions of modern jet drives. Further, the design of the new combustion chamber was to be conventional in order to retain the possibility of converting existing propulsion systems to the new technology. [German] Diese Notiz enthaelt den Abschlussbericht des Technologievorhabens 'NO{sub x}-Reduktion durch Homogenisierung des Gemisches in Brennkammern'. Das Vorhaben ist Teil des Luftfahrtfoerderprogramms Engine 3E 2010 der Bundesregierung und wird vom Bundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie (BMBF) unter dem Foerderkennzeichen 20T9540 gefoerdert. Das Programm wurde am 01. Juli 1995 begonnen und endete am 30. Juni 1999. Entsprechend dem Foerderantrag wurden in dem Vorhaben Einzeltechnologien erarbeitet, die erforderlich sind, um eine 60% Reduktion der NO{sub x}-Emissionen gegenueber ICAO '95 in einer Ringbrennkammer unter realistischen Betriebsbedingungen zu demonstrieren, wobei die restlichen Emissionen das Emissionsniveau moderner Triebwerke nicht ueberschreiten sollten. Darueber hinaus sollte das aeussere Design der zu entwickelnden Brennkammer sind von konventionellen Brennkammern nicht unterscheiden, um die Moeglichkeit der Umruestung von alten Triebwerken mit der Brennkammern der neuen Technologie offen zu halten. (orig.)

  14. Reduction of construction cost and carbon dioxide emissions by heat contracting. Obstacles and solutions. Final report; Baukostensenkung und CO{sub 2}-Minderung durch Waerme-Contracting. Hemmnisse und Loesungswege. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, V.; Liebernickel, T.; Froemel, T.; Kues, H.

    2000-11-01

    The poor condition of many heating systems is caused by a conflict of interest between investors and users. Landlords tended to opt for low investment cost, while the accompanying higher consumption cost was paid by their tenants. The only thing that has changed here is the fact that the 'secondary cost' has become a criterion for new tenants' decision to rent an apartment. Heat contracting may be a way out of the problem as contractors are interested in high-efficiency heating systems and optimally controlled operation. Heat contracting is a service concept of private and communal organisations that involves payment, construction and operation of a heating system by the contractor depending on the contracting model used. [German] Die relativ schlechte und veraltete heizungstechnische Ausruestung der Wohngebaeude in Deutschland ist auf den lange Jahre bestehenden Interessenkonflikt zwischen Investor und Nutzer im Mietwohnungsbau zurueckzufuehren. Durch die Umlagefaehigkeit der Heizkosten auf die Nutzer (Mieter) war der Gebaeudeeigentuemer i.d.R. bestrebt, eine Anlage zu guenstigen Investitionskosten zu erwerben. Die daraus resultierenden, relativ hoeheren Verbrauchskosten waren als Betriebskosten auf die Mieter umlegbar und belasteten den Vermieter nicht. An dieser Situation hat sich bis heute prinzipiell nichts geaendert; allerdings sind die Nebenkosten mit der Hauptkostenposition 'Heizkosten' zu einem Kriterium der Vermietbarkeit geworden, so dass der Vermieter heute die Kosten moeglichst niedrig halten muss. Ein Ausweg aus dem Interessenkonflikt und der neuen Vermietsituation koennte das Waerme-Contracting sein. Seitens des Contractors ist der Einsatz hocheffizienter Anlagentechnik und optimale, d.h. ueberwachte Betriebsbedingungen fuer einen wirtschaftlichen Erfolg unabdingbar. Waerme-Contracting ist ein Dienstleistungskonzept von privatwirtschaftlichen und kommunalen Unternehmen, die - je nach Contracting

  15. If science does create more than knowledge. A congress is asking for 'education by science'; Wenn Wissenschaft mehr als Wissen schafft. Ein Kongress fragt nach 'Bildung durch Wissenschaft'

    Energy Technology Data Exchange (ETDEWEB)

    Nuissl, E. (ed.)

    2002-07-01

    The role of science in the development of the so-called 'knowledge society' was investigated at this interdisciplinary congress. Three problem areas were identified: 1. Science itself must constantly review its own ethical fundamentals and investigate and extend its ability to keep a dialogue running. 2. Society is asked to provide an ethical and moral orientation for dealing with newly acquired knowledge and to define the social standing of science. 3. Each and every individual must work on maintaining and extending his or her level of knowledge in order to cope with everyday life and perform social functions. [German] Ziel des Kongresses ''Bildung durch Wissenschaft'' war es, im interdisziplinaeren Austausch die Rolle der Wissenschaft bei der Entwicklung der so genannten ''Wissensgesellschaft'' zu eroertern. Der enorme Wissenszuwachs des vergangenen Jahrhunderts bedeutet eine Zunahme des ''Machbaren'', von dessen positiven wie negativen Folgen die Gesellschaft und der Einzelne gleichermassen betroffen ist. Das gilt gerade fuer diejenigen Technologien und Wissensbestaende, die im Alltag von Bedeutung sind. Der Kongress beschaeftigte sich mit diesen Entwicklungen und mit den Problemen, die sich daraus ergeben. Der erste Problemkreis betrifft die Wissenschaft selbst: Sie muss sich ihrer eigenen ethischen Grundlagen wieder neu vergewissern, ihre Dialogfaehigkeit ueberpruefen und erweitern. Ein zweiter Problemkreis ist auf Seiten der Oeffentlichkeit auszumachen: Die Gesellschaft wird ethische und moralische Orientierungen fuer den Umgang mit dem neu erworbenen Wissen schaffen und grundsaetzlich den gesellschaftlichen Stellenwert der Wissenschaft bestimmen muessen. Der dritte Problemkreis stellt sich dem Einzelnen: Jeder ist gefordert, kontinuierlich sein Wissensniveau zu erhalten und zu erweitern, um den Alltag bewaeltigen und gesellschaftliche Aufgaben wahrnehmen zu koennen. (orig.)

  16. Deposit formation by 20 % (V/V) FAME fuels in premix burner systems; Ablagerungsbildung durch 20% (V/V) FAME-Brennstoffe in Vormischbrennersystemen

    Energy Technology Data Exchange (ETDEWEB)

    Jaschinski, Christian; Rheinberg, Oliver van [OWI Oel-Waerme-Institut GmbH, Aachen (Germany); RWTH Aachen (Germany). An-Institut

    2012-09-15

    In the domestic heating market the development and use of fuels with an increasing share of biogenic or alternative fuels is propagated. Due to the fact, that modern fuel oil burner feature a complex carburation techniques and combustion, changes on the fuel properties and composition can lead to increased emissions or deposit formation therein. Furthermore, the different fuel properties may result in decreased storage stability, which has to be evaluated before introducing them into the market. The scope of the project was to investigate the performance of low-sulfur domestic heating oil (DHO) with up to 20 % v/v FAME on the storage stability and on the use in oil-fired heating systems. The project was split into two major parts. The first part covered a two-year storage of the fuels including sampling and analysis of the fuels every half year. The analysis was conducted according to DIN 51603-1 for the pure DHO and according to DIN SPEC 51603-6 for the blends. It has been shown, that low sulphur domestic heating oil with up to 20 % (V/V) of FAME after two years of storage fits the parameter of the corresponding standards. Furthermore, a new testing method, called 'DGMK-714' derived from the PetroOxy-test (EN 16091) has been defined. With this method for the determination of oxidation stability the fuels can be characterized being comparable to the standardized testing methods of modified Rancimat or PetroOxy. The higher sample volume of the method allows further analysis of the fuel sample after testing for characterization of the fuels. The second part of the project investigated the deposit formation tendencies of the fuels in an idealized testing apparatus and in three different kinds of oil burners. Using the idealized testing apparatus proved an increased tendency of deposit formation during evaporation for an increasing FAME content. However, this tendency could not be observed in the three commercial oil-fired heating systems. A precise fuel

  17. Thermally exfoliated graphite oxide

    Science.gov (United States)

    Prud'Homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor); Abdala, Ahmed (Inventor)

    2011-01-01

    A modified graphite oxide material contains a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g, wherein the thermally exfoliated graphite oxide displays no signature of the original graphite and/or graphite oxide, as determined by X-ray diffraction.

  18. The Enzymatic Oxidation of Graphene Oxide

    Science.gov (United States)

    Kotchey, Gregg P.; Allen, Brett L.; Vedala, Harindra; Yanamala, Naveena; Kapralov, Alexander A.; Tyurina, Yulia Y.; Klein-Seetharaman, Judith; Kagan, Valerian E.; Star, Alexander

    2011-01-01

    Two-dimensional graphitic carbon is a new material with many emerging applications, and studying its chemical properties is an important goal. Here, we reported a new phenomenon – the enzymatic oxidation of a single layer of graphitic carbon by horseradish peroxidase (HRP). In the presence of low concentrations of hydrogen peroxide (~40 µM), HRP catalyzed the oxidation of graphene oxide, which resulted in the formation of holes on its basal plane. During the same period of analysis, HRP failed to oxidize chemically reduced graphene oxide (RGO). The enzymatic oxidation was characterized by Raman, UV-Vis, EPR and FT-IR spectroscopy, TEM, AFM, SDS-PAGE, and GC-MS. Computational docking studies indicated that HRP was preferentially bound to the basal plane rather than the edge for both graphene oxide and RGO. Due to the more dynamic nature of HRP on graphene oxide, the heme active site of HRP was in closer proximity to graphene oxide compared to RGO, thereby facilitating the oxidation of the basal plane of graphene oxide. We also studied the electronic properties of the reduced intermediate product, holey reduced graphene oxide (hRGO), using field-effect transistor (FET) measurements. While RGO exhibited a V-shaped transfer characteristic similar to a single layer of graphene that was attributed to its zero band gap, hRGO demonstrated a p-type semiconducting behavior with a positive shift in the Dirac points. This p-type behavior rendered hRGO, which can be conceptualized as interconnected graphene nanoribbons, as a potentially attractive material for FET sensors. PMID:21344859

  19. Tin-antimony oxide oxidation catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Berry, Frank J. [Open University, Department of Chemistry (United Kingdom)

    1998-12-15

    Tin-antimony oxide catalysts for the selective oxidation of hydrocarbons have been made by precipitation techniques. The dehydration of the amorphous dried precipitate by calcination at increasingly higher temperatures induces the crystallisation of a rutile-related tin dioxide-type phase and the segregation of antimony oxides which volatilise at elevated temperatures. The rutile-related tin dioxide-type phase contains antimony(V) in the bulk and antimony(III) in the surface. Specific catalytic activity for the oxidative dehydrogenation of butene to butadiene is associated with materials with large concentrations of antimony(III) in the surface.

  20. Oxidation films morphology

    International Nuclear Information System (INIS)

    Paidassi, J.

    1960-01-01

    After studying the oxidation of several pure polyvalent metals (Fe, Cu, Mn, Ni, U) and of their oxides at high temperature and atmospheric pressure, the author suggests how to modify the usual representation of the oxide film (a piling of different oxide layers, homogeneous on a micrographic scale with a equi-axial crystallisation, free of mechanical tensions, with flat boundary surfaces) to have it nearer to reality. In this first part, the author exposes the study of the real micrographic structure of the oxidation film and gives examples of precipitation in the oxides during the cooling of the oxidised sample. (author) [fr

  1. Optimised utilisation of existing incinerators by installation of upstream reactors for treatment of waste with high calorifica value - HYBRID waste treatment plants; Optimierte Nutzung bestehender Abfallverbrennungsanlagen durch Errichtung vorgeschalteter Reaktoren zur Behandlung heizwertreicher Abfaelle - HYBRID-Abfallbehandlungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    El Labani, M

    2000-07-01

    Abfallverbrennungsanlagen nachtraeglich um leistungsfaehige Rauchgasreinigungssysteme ergaenzt werden. Dies fuehrte zu einem erheblichen Anstieg der Kosten und Behandlungsgebuehren mit dem entsprechenden Druck zur optimierten Nutzung. Zusaetzliche Behandlungskapazitaeten werden benoetigt fuer heizwertreiche Abfaelle. Sie koennen zwar in konventionellen Abfallverbrennungsanlagen fuer Hausmuell behandelt werden, bedingen aber aufgrund des hoeheren Heizwertes eine Durchsatzreduzierung was die Kostensituation weiter negativ beeinflusst. Daher favorisieren aktuelle Konzepte die Behandlung heizwertreicher Abfaelle in spezifischen, dezentralen Anlagen. Die ueblicherweise kleinen Anlagen gehen einher mit hohen Nebenkosten der Errichtung. Zur Abschaetzung des Optimierungspotentials bestehender Abfallverbrennungsanlagen wurde deren Auslastungssituation untersucht. Bei umfangreichen Messkampagnen am MHKW Darmstadt konnte selbst bei 100%iger Auslastung der Verbrennungseinheit in der Rauchgasreinigungsanlage eine Luecke aufgezeigt werden, die durch eine entsprechend angepasste Vorschaltanlage aufgefuellt werden koennte. Eine solche Vorschaltanlage definiert zusammen mit der bestehenden Abfallverbrennungsanlage eine HYBRID-Abfallbehandlungsanlage. Die Bereitstellung eines Instrumentariums zur Unterstuetzung der Entscheidungsfindung bei der Konzeption solcher Anlagen ist Gegenstand dieser Arbeit. (orig.)

  2. Durch Kooperation und Vernetzung zu neuen Aufgabenfeldern – Serviceentwicklung in der Bibliothek der Medizinischen Fakultät Mannheim [Opening up new tasks through cooperation and networking – service development in the Library for the Medical Faculty of Mannheim

    Directory of Open Access Journals (Sweden)

    Semmler-Schmetz, Martina

    2013-09-01

    Full Text Available [english] The Library for the Medical Faculty of Mannheim of the University of Heidelberg supplies literature and information for research, teaching and further education purposes at the “Universitätsmedizin Mannheim”. Cooperation and networking with the central facilities, departments, working groups, and information multipliers result in new, future-oriented areas of work that go beyond traditional library tasks. New services for students focus primarily on academic research and writing skills, while information and consulting services which are flexible in terms of time and location are being developed for staff members of the clinical departments and institutes. The recent cooperation with actors in the field of evidence-based medicine has yielded the innovative service “systematic literature search” which is designed to support doctors and scientists in the preparation of grant proposals for clinical trials, systematic reviews, and guidelines. Currently, the library is widening access to its new services to include doctors, scientists, and other health practitioners in the region, and evaluating chargeable services for these user groups.[german] Die Bibliothek der Medizinischen Fakultät Mannheim der Universität Heidelberg dient der Literatur- und Informationsversorgung für Forschung, Lehre, Fort- und Weiterbildung an der Universitätsmedizin Mannheim. Neue, zukunftsorientierte Aufgabenfelder, die über die klassischen bibliothekarischen Arbeitsschwerpunkte hinausgehen, erschließt sich die Bibliothek durch enge Kooperation und Vernetzung mit den zentralen Einrichtungen und Abteilungen, Arbeitskreisen und Multiplikatoren innerhalb der Universitätsmedizin Mannheim. Neue Services für die Zielgruppe der Studierenden richten sich vor allem auf den Bereich des wissenschaftlichen Arbeitens, während für Mitarbeiter in den Einrichtungen, Kliniken und Instituten der Universitätsmedizin zeitlich und räumlich flexible Informations

  3. Internal fuel pin oxidizer

    International Nuclear Information System (INIS)

    Andrews, M.G.

    1978-01-01

    A nuclear fuel pin has positioned within it material which will decompose to release an oxidizing agent which will react with the cladding of the pin and form a protective oxide film on the internal surface of the cladding

  4. Oxidation-resistant cermet

    Science.gov (United States)

    Phillips, W. M.

    1977-01-01

    Chromium metal alloys and chromium oxide ceramic are combined to produce cermets with oxidation-resistant properties. Application of cermets includes use in hot corrosive environments requiring strong resistive materials.

  5. Bridged graphite oxide materials

    Science.gov (United States)

    Herrera-Alonso, Margarita (Inventor); McAllister, Michael J. (Inventor); Aksay, Ilhan A. (Inventor); Prud'homme, Robert K. (Inventor)

    2010-01-01

    Bridged graphite oxide material comprising graphite sheets bridged by at least one diamine bridging group. The bridged graphite oxide material may be incorporated in polymer composites or used in adsorption media.

  6. Oxidative phosphorylation revisited

    DEFF Research Database (Denmark)

    Nath, Sunil; Villadsen, John

    2015-01-01

    The fundamentals of oxidative phosphorylation and photophosphorylation are revisited. New experimental data on the involvement of succinate and malate anions respectively in oxidative phosphorylation and photophosphorylation are presented. These new data offer a novel molecular mechanistic...

  7. Oxidative Stress in Neurodegeneration

    Directory of Open Access Journals (Sweden)

    Varsha Shukla

    2011-01-01

    Full Text Available It has been demonstrated that oxidative stress has a ubiquitous role in neurodegenerative diseases. Major source of oxidative stress due to reactive oxygen species (ROS is related to mitochondria as an endogenous source. Although there is ample evidence from tissues of patients with neurodegenerative disorders of morphological, biochemical, and molecular abnormalities in mitochondria, it is still not very clear whether the oxidative stress itself contributes to the onset of neurodegeneration or it is part of the neurodegenerative process as secondary manifestation. This paper begins with an overview of how oxidative stress occurs, discussing various oxidants and antioxidants, and role of oxidative stress in diseases in general. It highlights the role of oxidative stress in neurodegenerative diseases like Alzheimer's, Parkinson's, and Huntington's diseases and amyotrophic lateral sclerosis. The last part of the paper describes the role of oxidative stress causing deregulation of cyclin-dependent kinase 5 (Cdk5 hyperactivity associated with neurodegeneration.

  8. Zinc oxide overdose

    Science.gov (United States)

    Zinc oxide is an ingredient in many products. Some of these are certain creams and ointments used ... prevent or treat minor skin burns and irritation. Zinc oxide overdose occurs when someone eats one of ...

  9. Oxidative Stress in BPH

    Directory of Open Access Journals (Sweden)

    Murat Savas

    2009-01-01

    The present study has shown that there were not relationship between potency of oxidative stress and BPH. Further well designed studies should be planned to find out whether the oxidative stress-related parameters play role in BPH as an interesting pathology in regard of the etiopathogenesis. Keywords: benign prostatic hyperplasia, oxidative stress, prostate

  10. Oxidation and Reduction of Iron-Titanium Oxides in Chemical Looping Combustion: A Phase-Chemical Description Oxydation et réduction des minerais de fer-titane dans la combustion en boucle chimique

    Directory of Open Access Journals (Sweden)

    den Hoed P.

    2011-05-01

    Full Text Available Ilmenite (FeTiO3 is being explored as an oxygen carrier in chemical looping processes. Its reduction and oxidation are described by the system Fe-Fe2O3-TiO2-Ti2O3. The phase diagram at 1 000°C, presented here, offers a useful tool for predicting reactions and their products. We see that Fe2TiO5 (pseudobrookite and TiO2 (rutile form a stable phase assemblage following the oxidation of FeTiO3 (ilmenite in air. The subsequent reduction of Fe2TiO5 at oxygen partial pressures of 10-15.5atm stabilizes Fe1.02Ti0.98O3, a solid solution of ilmenite. Further reduction will produce metallic iron, which compromises the integrity of the oxygen carrier for chemical looping processes. We speculate that the reduction of Fe-Ti oxides in several practical instances does not reach completion (and equilibrium under the imposed atmospheres operating in fuel reactors. L’ilménite (FeTiO3 est considéré comme un transporteur d’oxygène potentiel pour les procédés en boucle chimique. Ses mécanismes de réduction et d’oxydation sont décrits à travers le système Fe-Fe2O3-TiO2-TiO3. Le diagramme de phase à 1 000°C, présenté ici, est un outil utile pour prédire les réactions et les produits. Nous constatons que Fe2TiO5 (pseudobrookite et TiO2 (rutile forment un assemblage de phase stable après oxydation de l’ilménite (FeTiO3 dans l’air. La réduction subséquente de Fe2TiO5 à la pression partielle de 10−15,5atm stabilise vers Fe1.02Ti0.98O3, une solution solide d’ilménite. Une réduction plus poussée va produire du fer métallique et compromettre l’intégrité du transporteur d’oxygène dans la boucle chimique. Il est probable que la réduction des oxydes Fe-Ti ne soit pas, en pratique, complète et n’atteigne pas l’équilibre dans les conditions rencontrées en opération dans les réacteurs de réduction.

  11. Internationale Wachstumsstrategien produzierender Familienunternehmen durch Mergers & Acquisitions

    NARCIS (Netherlands)

    Sachs, Andreas Fabian Constantin Johannes

    2007-01-01

    Family businesses are experiencing a revival in the German economy. In the face of the challenges of globalization and the ongoing relocation of production facilities, “home base oriented” enterprises meet with increasing attention and gain in importance. Family-owned enterprises have indeed been

  12. Wolframcarbid/Silber-Kontaktwerkstoffe durch Gasdruckinfiltration

    OpenAIRE

    Stadler, Thomas

    2017-01-01

    von Thomas Stadler Arbeit an der Bibliothek noch nicht eingelangt - Daten nicht geprueft Abweichender Titel nach Übersetzung der Verfasserin/des Verfassers Technische Universität Wien, Univ., Diplomarbeit, 2017

  13. Erkenntnisgewinnn durch Virtuelle Realitäten

    Directory of Open Access Journals (Sweden)

    Breiner, Tobias

    2009-11-01

    Full Text Available Virtual reality will gain a more and more important role in our everyday life. So it is very important to understand fully the impact and influence virtual reality will have on or view of the world. This article reveals that the interdependencies between the real space and the virtual space are much more subtle and profound then on first sight. Especially the value of several mathematical, physical and biological models and simulation methodologies will be reestimated by the use of virtual reality in the long term. As an example the article describes the historical chain from quaternions to quaoaring and how this may lead to a paradigm change in biology.

  14. Safety by simulation; Sicherheit durch Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Eberhard [KSG Kraftwerks-Simulator-Gesellschaft mbH, Essen (Germany); GfS Gesellschaft fuer Simulatorschulung mbH, Essen (Germany)

    2009-06-15

    Simulator training is a key component in achieving and preserving on the long term the necessary expertise of plant personnel also required by the authorities. In this way, it makes an important contribution to the safe operation of nuclear power plants. Simulators are a component in the training of operating personnel of nuclear power plants which allows nuclear power plant operators to be prepared in a focused and practice-oriented way for their activity in everyday plant operation and for possible accident simulation. The simulator center is supported by 5 nuclear power plant operators: the German E.ON Kernkraft GmbH, RWE Power AG, EnBW Kraftwerke AG, and Vattenfall Europe Nuclear Energy GmbH companies as well as the Netherlands N.V. Electriciteits-Produktiemaatschappij Zuid-Nederland. They established a joint enterprise in Essen which performs in one central place the duty of simulator training incumbent upon all nuclear power plants. (orig.)

  15. Health injuries by noise; Gesundheitsgefahren durch Laerm

    Energy Technology Data Exchange (ETDEWEB)

    Plath, P [Klinik fuer Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie, Bochum Univ., Prosper-Hospital, Recklinghausen (Germany)

    1995-07-01

    Within the civilized world, noise is a common danger for health. There is not only the well known hearing loss by occupational noise, but there are also a lot of noise induced hearing losses by noise injuries in private life which are comparable to the occupational ones. The sources of these injuries within private life mostly are unknown and can be found in household goods as well as from listening to loud music. Also the danger from loud cracks mostly is underestimated, so as the cracks from children toys often reach more than 150 dB(Al). Alladay`s noise levels, e.g. in public trafic, also reach dangerous levels, and the sum of all these noise injuries results in a lesion of the cilias of the outer hair cells in the Corti`s organ. The resulting hearing loss is called `sociacusis` and increases the effect of physiological presbyacusis to an amount that results in the fact, that more than 10% of all adults in civilized countries have a severe, handicapping deafness. The immediate effect of noise in this regard is intensified by the effects of disturbing noise onto the psychovegetative and hormonal regulations by chronical stress. So people in civilized countries are going to become a society of hard hearing subjects, and deafness will become a common peoples` disease. (orig.) [Deutsch] Laerm ist in der zivilisierten Welt ein allgemeines Gesundheitsproblem. Es gibt nicht nur die berufliche Laermschwerhoerigkeit, die gut erforscht ist, sondern schaedlicher Laerm tritt sehr oft auch im Privatleben auf und verursacht Gehoerschaeden, die der beruflich bedingten Laermschwerhoerigkeit vergleichbar sind. Die Gehoergefaehrdung im Privatleben ist oft unbekannt und betrifft neben lauten Geraeten im Haushalt und dem Hoeren zu lauter Musik auch die oft in ihrer Gefaehrlichkeit unterschaetzten Knalle, die selbst bei Kinderspielzeug Spitzenwerte der Pegel von ueber 150 dB(Al) erreichen. Die allgemeine zivilisatorische Laermbelastung, z.B. im oeffentlichen Verkehr, die oft schaedigende Ausmasse erreicht, im Beurteilungspegel aber unter den Grenzwerten bleibt, bewirkt im Laufe der Jahre ebenfalls bleibende Schaeden an der Zilien der aeusseren Haarzellen des Corti-Organs, die eine ueber die physiologische Alterung hinausgehende `Soziakusis` bewirken. Schliesslich haben die staendigen Geraeusch- und Laermbelaestigungen und -stoerungen des Alltagslebens deutliche Effekte auf die neurovegetativen und hormonellen Regulationen des Organismus und verursachen somit mittelbar ueber Stressreaktionen ebenfalls Hoerstoerungen in Form von Hoerstuerzen und Tinnitus. Der alltaegliche Laerm, dem zu wenig Bedeutung zugemessen wird, droht Schwerhoerigkeit, von der mehr als 10% aller Erwachsenen betroffen sind, zur Volkskrankheit werden zu lassen. (orig.)

  16. "Fine-tuning" durch interkulturelles Coaching

    OpenAIRE

    Steixner, Margret

    2009-01-01

    Margret Steixner plädiert in ihrem Beitrag für eine Integration des interkulturellen Coachings in andere Bereiche des Coachings. Basierend auf einer Coaching-Fallstudie entwickelt die Autorin einen hilfreichen Fragenkatalog für das interkulturelle Coaching. Intercultural Coaching identifies and develops intercultural competence as a key to success in the international and globalised work environment. Coaching in general has gained recognition as a very suitable method for competence develo...

  17. Sputtered indium oxide films

    International Nuclear Information System (INIS)

    Gillery, F.H.

    1986-01-01

    A method is described for depositing on a substrate multiple layer films comprising at least one primary layer of a metal oxide and at least one primary layer of a metal other than the metal of the oxide layer. The improvement described here comprises improving the adhesion between the metal oxide and metal layers by depositing between the layers an intermediate metal-containing layer having an affinity for both the metal and metal oxide layers. An article of manufacture is described comprising a nonmetallic substrate, and deposited thereon in any order: a. at least one coating layer of metal; b. at least one coating layer of an oxide of a metal other than the metal of the metal layer; and c. deposited between the metal and metal oxide layers an intermediate metal-containing layer having an affinity for both the metal and metal oxide layers

  18. Modeling and experimental validation of CO heterogeneous chemistry and electrochemistry in solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Yurkiv, Vitaly

    2010-12-17

    -Reaktionssysteme zu erhalten. Unter Verwendung dieser Daten wurden auf Elementarreaktionen basierende mikrokinetische Modelle, die vier verschiedene Ladungstransfermechanismen enthielten, fuer die elektrochemische CO-Oxidation entwickelt und zur numerischen Simulation experimenteller elektrochemischer Literaturdaten wie Polarisationskurven und Impedanzspektren herangezogen. Durch Vergleich zwischen Simulation und Experiment konnte gezeigt werden, dass nur einer der vier Ladungstransfermechanismen die vorhandenen elektrochemischen Daten ueber einen weiten Temperatur- und CO/CO{sub 2}-Gaszusammensetzungsbereich konsistent reproduzieren kann.

  19. Oxidation Resistant Graphite Studies

    Energy Technology Data Exchange (ETDEWEB)

    W. Windes; R. Smith

    2014-07-01

    The Very High Temperature Reactor (VHTR) Graphite Research and Development Program is investigating doped nuclear graphite grades exhibiting oxidation resistance. During a oxygen ingress accident the oxidation rates of the high temperature graphite core region would be extremely high resulting in significant structural damage to the core. Reducing the oxidation rate of the graphite core material would reduce the structural effects and keep the core integrity intact during any air-ingress accident. Oxidation testing of graphite doped with oxidation resistant material is being conducted to determine the extent of oxidation rate reduction. Nuclear grade graphite doped with varying levels of Boron-Carbide (B4C) was oxidized in air at nominal 740°C at 10/90% (air/He) and 100% air. The oxidation rates of the boronated and unboronated graphite grade were compared. With increasing boron-carbide content (up to 6 vol%) the oxidation rate was observed to have a 20 fold reduction from unboronated graphite. Visual inspection and uniformity of oxidation across the surface of the specimens were conducted. Future work to determine the remaining mechanical strength as well as graphite grades with SiC doped material are discussed.

  20. „Wir verbrachten mehr als 24 Stunden, ohne etwas anderes als Schokolade und Limonade zu uns zu nehmen“. Hinweise in Alexander von Humboldts Tagebuchaufzeichnungen zu Fragen der Verpflegung auf der Forschungsreise durch Spanisch-Amerika

    Directory of Open Access Journals (Sweden)

    Ursula Thiemer-Sachse

    2013-12-01

    Full Text Available Zusammenfassung In Alexander von Humboldts Tagebüchern seiner berühmten Forschungsreise durch Spanisch-Amerika finden sich Bemerkungen und Hinweise für künftige Leser seiner Reisedarstellungen zu Problemen der Verpflegung. Zumeist werden Engpässe und Missstände erwähnt sowie Fragen soziopolitischer Situation verdeutlicht. Sie beziehen sich auf Extrembedingungen in stadtfernen Gebieten und im Kontakt mit den indigenen Trägern und Helfern während der einzelnen Exkursionen. Die Darstellungen der alltäglichen Gegebenheiten sind zugleich eine interessante Quelle für Verhaltensmuster der verschiedenen Schichten der spanischkolonialen Gesellschaft wie der Forschungsreisenden, die mit den Schwierigkeiten umzugehen hatten, sich anzupassen verstanden oder ihre eigenen Verhaltensmuster entwickelt haben. Damit ermöglichen Humboldts Aufzeichnungen zugleich auch auf diesem Gebiet manchen Blick auf den seither erfolgten Kulturwandel. Resumen En los diarios del famoso viaje de estudios de Alejandro de Humboldt por la América española se encuentran observaciones y notas sobre problemas de aprovisionamiento, en favor de lectores futuros de sus relaciones de viaje. En la mayoría de los casos Humboldt menciona situaciones precarias o ilustra cuestiones de carácter sociopolítico. Frecuentemente, sus apuntes se refieren a condiciones extremas en regiones remotas y en contacto con los cargadores y ayudantes indígenas durante las diferentes excursiones. Las descripciones de los acontecimientos cotidianos al mismo tiempo son una fuente interesante sobre los modos de proceder de las diferentes capas de la sociedad colonial española así como de los viajeros científicos que tuvieron que enfrentar dificultades a las cuales había que adaptarse o desarrollar modelos propios de comportamiento. Por esto al mismo tiempo las noticias de Humboldt también en este asunto posibilitan más de una vez la atención al cambio cultural que se ha realizado hasta hoy

  1. Der Einfluss von Anonymität in der Lehrevaluation durch Studierende [The Effects of Anonymity on Student Ratings of Teaching and Course Quality in a Bachelor Degree Programme

    Directory of Open Access Journals (Sweden)

    Schaffner, Noemi

    2013-08-01

    is being taken seriously; consequently, they feel able to provide a constructive and honest evaluation.[german] Zielsetzung und Fragestellung: Unterscheiden sich die Ergebnisse anonymisierter und personalisierter Evaluationen? Methodik: Während zweier Jahre wurden bei jeder Modulevaluation alle Studierenden randomisiert den Halbgruppen „anonym“ und „personalisiert“ zugeteilt. Die Qualität des Moduls in seinen relevanten Aspekten wurde mit einem standardisierten Fragebogen erhoben. Zusätzlich konnten optionale Textantworten formuliert werden. Drei unabhängige Personen bewerteten die Aussagequalität der Antworten gemäss einem Leitfaden. Dieser beinhaltete die fünf Dimensionen positiv-negativ, differenziert-absolut, Nennung einer Person-allgemein, Befehl enthaltend-neutral und optisch akzentuiert-blank. Der Datensatz bestand aus 615 Fragebogen, davon waren 306 in anonymer Form. Mit einer multivariaten Varianzanalyse wurde überprüft, ob sich zwischen anonym und personalisiert erhobenen Daten ein Unterschied sowohl bei den durch Skalen bewerteten Aspekten als auch bei der Qualität der optionalen Textantworten zeigte. Zusätzlich wurde untersucht, ob sich die Häufigkeit der optionalen Textantworten unterschied.Ergebnisse: In der Aussagequalität liess sich kein signifikanter Unterschied zwischen anonym und personalisiert erhobenen Daten nachweisen. Hingegen haben Studierende aus der personalisierten Gruppe tendenziell häufiger optionale Textantworten geliefert.Schlussfolgerung: Personalisierte Evaluationen generieren dann keine verfälschten Resultate im Sinne der sozialen Erwünschtheit, wenn der Evaluationszirkel geschlossen und transparent ist: Die Verantwortlichen melden den Studierenden die Evaluationsergebnisse konsequent zurück und Änderungs-, Optimierungswünsche und Umsetzungsmöglichkeiten werden mit ihnen diskutiert. Die Studierenden erfahren so, dass ihre Rückmeldungen ernst genommen werden. So können sie sich echte Kritik erlauben.

  2. Parameters for characterisation of the ecochemical soil status and the potential hazards of acidification and nitrogen saturation in level II forest sites; Kennwerte zur Charakterisierung des oekochemischen Bodenzustandes und des Gefaehrdungspotentials durch Bodenversauerung und Stickstoffsaettigung an Level II-Waldoekosystem-Dauerbeobachtungsflaechen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The ad hoc working group on soil acidification and nitrogen saturation of the Federal Government/Laender Working Group level II primarily aimed at drafting a manual for the interpretation of soil data (soil solid phase, soil solution) acquired on Level II plots. The manual contains parameters and proposals for evaluating the acid/base-status of forest soils, the nutrient supply and nitrogen status as well as for assessing the risks caused by aluminium, acid and heavy metal stress. Further parameters and proposals for evaluation concern the risks for spring and ground water quality through acidification and elevated nitrate concentrations. All parameters are described in detail, their informative value is discussed and examples are given for their use. A distinction is made between indicators to show the current ecochemical situation and to describe future risks, e.g. through progressive soil acidification, nutrient depletion and increasing nitrogen saturation. The manual thus fits in right with the overall objectives of the Level II Programme to reveal cause-effect relations in the forest damage situation and to give advice on timely counteraction via forecasts of the future development. (orig.) [German] Das vorrangige Ziel des Arbeitskreises 'Bodenversauerung und Stickstoffsaettigung' der Bundes-Laender-Arbeitsgruppe Level II war die Erarbeitung eines Auswerteleitfadens fuer die Bodendaten (Bodenfestphase, Sickerwasser) der Level II-Flaechen. Der Leitfaden enthaelt Kennwerte und Bewertungsvorschlaege zum Saeure-Base-Zustand des Waldbodens, zur Naehrstoffbereitstellung, zum Stickstoffstatus, zur Abschaetzung von Risiken durch Aluminium-, Saeure- und Schwermetallstress und zur Gefaehrdung des Quell- und Grundwassers durch Versauerung und steigende Nitratgehalte. Alle Kennwerte werden eingehend beschrieben, ihre Aussagekraft diskutiert und ihre Anwendung an Beispielen dargestellt. Unterschieden wird zwischen Indikatoren zur Darstellung der aktuellen

  3. Reduction of {sup 137}caesium contamination in wild boars by supplementing offered food with ammonium-iron-hexa-cyanoferrate; Reduktion der {sup 137}Caesium-Aktivitaet in Wildschweinen durch Zusatz von Ammonium-Eisen-Hexacyanoferrat (''Berliner Blau'') zum Kirrfutter

    Energy Technology Data Exchange (ETDEWEB)

    Morfeld, P. [Evonik Industries AG, Essen (Germany). Inst. fuer Epidemiologie und Risikobewertung in der Arbeitswelt (IERA); Koeln Univ. (Germany). Inst. und Poliklinik fuer Arbeitsmedizin, Umweltmedizin und Praeventionsforschung; Reddemann, J.; Schungel, P. [Landesjagdverband Bayern e.V., Feldkirchen (Germany); Kienzle, E. [Muenchen Univ., Oberschleissheim (Germany). Lehrstuhl fuer Tierernaehrung und Diaetetik

    2014-06-15

    This replication study investigated whether the {sup 137}caesium ({sup 137}Cs) contamination of wild boars could be relevantly reduced under field conditions by adding ammonium-iron-hexa-cyanoferrate (AFCF; Prussian blue) to the food. In 285 wild boars that had been shot in six Bavarian hunting territories during the season (November until May) between 01 November 2010 and 10 December 2011 {sup 137}Cs contamination was analysed. Thirty-five animals originated from two hunting territories in which offered food had been supplemented with 1250 mg AFCF per kilogram food. The control animals showed a mean {sup 137}Cs contamination of 522 Bq/kg lean skeletal muscle meat. Direct (univariable) comparisons of the two experimental territories with the four control territories yielded a mean reduction in {sup 137}Cs contamination due to Prussian bluefeeding by -211 Bq/kg (p < 0.001). Multivariable mo dels that took potential confounders into account (age, weight, sex, hunting date, territory) estimated the effect to be -344 Bq/kg (p < 0.05). This replication study confirmed the finding of Kienzle et al. (12) who described a statistically significant reduction in {sup 137}Cs contamination by -380 Bq/kg due to the feeding of Prussian blue in other territories. [German] Gegenstand und Ziel: Diese Replikationsstudie pruefte, ob unter Feldbedingungen die Kontamination von Wildschweinen mit {sup 137}Caesium ({sup 137}Cs) durch Zugabe vn Ammonium-Eisen-Hexacyanoferrat (AFCF, ''Berliner Blau'') zum ausgelegten Futter relevant verringert werden kann. Material und Methoden: Bei 285 Wildschweinen, die zwischen dem 01.11.2010 und dem 10.12.2011 waehrend der Jagdsaison (November bis Mai) in sechs bayerischen Jagdrevieren erlegt worden waren, erfolgte eine Analyse der {sup 137}Cs-Aktivitaet. Von diesen Tieren stammten 35 aus zwei Revieren, in denen das ausgelegte Futter mit 1250 mg AFCF/kg Futter supplementiert worden war. Ergebnisse: Die Kontrolltiere wiesen eine

  4. Barium oxide, calcium oxide, magnesia, and alkali oxide free glass

    Science.gov (United States)

    Lu, Peizhen Kathy; Mahapatra, Manoj Kumar

    2013-09-24

    A glass composition consisting essentially of about 10-45 mole percent of SrO; about 35-75 mole percent SiO.sub.2; one or more compounds from the group of compounds consisting of La.sub.2O.sub.3, Al.sub.2O.sub.3, B.sub.2O.sub.3, and Ni; the La.sub.2O.sub.3 less than about 20 mole percent; the Al.sub.2O.sub.3 less than about 25 mole percent; the B.sub.2O.sub.3 less than about 15 mole percent; and the Ni less than about 5 mole percent. Preferably, the glass is substantially free of barium oxide, calcium oxide, magnesia, and alkali oxide. Preferably, the glass is used as a seal in a solid oxide fuel/electrolyzer cell (SOFC) stack. The SOFC stack comprises a plurality of SOFCs connected by one or more interconnect and manifold materials and sealed by the glass. Preferably, each SOFC comprises an anode, a cathode, and a solid electrolyte.

  5. Direct oxide reducing method

    International Nuclear Information System (INIS)

    Tokiwai, Moriyasu.

    1995-01-01

    Calcium oxides and magnetic oxides as wastes generated upon direct reduction are subjected to molten salt electrolysis, and reduced metallic calcium and magnesium are separated and recovered. Then calcium and magnesium are used recyclically as the reducing agent upon conducting direct oxide reduction. Even calcium oxides and magnesium oxides, which have high melting points and difficult to be melted usually, can be melted in molten salts of mixed fluorides or chlorides by molten-salt electrolysis. Oxides are decomposed by electrolysis, and oxygen is removed in the form of carbon monoxide, while the reduced metallic calcium and magnesium rise above the molten salts on the side of a cathode, and then separated. Since only carbon monoxide is generated as radioactive wastes upon molten salt electrolysis, the amount of radioactive wastes can be greatly reduced, and the amount of the reducing agent used can also be decreased remarkably. (N.H.)

  6. Oxidizer Scoping Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chancellor, Christopher John [Los Alamos National Laboratory

    2016-11-07

    The purpose of this report is to present the results of the acceptable knowledge (AK) review of oxidizers present in active waste streams, provide a technical analysis of the oxidizers, and report the results of the scoping study testing. This report will determine the fastest burning oxidizer to be used in the development of a Test Plan for Preparation and Testing of Sorbents Mixed with Oxidizer found in Transuranic Waste (DWT-TP-001). The companion report, DWT-RPT-002, Sorbent Scoping Studies, contains similar information for sorbents identified during the AK review of TRU waste streams. The results of the oxidizer and sorbent scoping studies will be used to inform the QL1 test plan. The QL1 test results will support the development of a basis of knowledge document that will evaluate oxidizing chemicals and sorbents in TRU waste and provide guidance for treatment.

  7. Review of zircaloy oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias, F.C. [Royal Military College of Canada, Kingston, Ontario (Canada); Lewis, B.J. [Univ. of Ontario Inst. of Technology, Faculty of Energy Systems and Nuclear Science, Oshawa, Ontario (Canada)

    2013-07-01

    This paper provides an overview of the kinetics for Zircaloy clad oxidation behaviour in steam and air during reactor accident conditions. The generation of chemical heat from metal/water reaction is considered. The effect of internal clad oxidation due to Zircaloy/UO{sub 2} interaction is also discussed. Low-temperature oxidation of Zircaloy due to water-side corrosion is further described. (author)

  8. OXIDATION OF TRANSURANIC ELEMENTS

    Science.gov (United States)

    Moore, R.L.

    1959-02-17

    A method is reported for oxidizing neptunium or plutonium in the presence of cerous values without also oxidizing the cerous values. The method consists in treating an aqueous 1N nitric acid solution, containing such cerous values together with the trivalent transuranic elements, with a quantity of hydrogen peroxide stoichiometrically sufficient to oxidize the transuranic values to the hexavalent state, and digesting the solution at room temperature.

  9. METAL OXIDE NANOPARTICLES

    Energy Technology Data Exchange (ETDEWEB)

    FERNANDEZ-GARCIA,M.; RODGRIGUEZ, J.A.

    2007-10-01

    This chapter covers the fundamental science, synthesis, characterization, physicochemical properties and applications of oxide nanomaterials. Explains fundamental aspects that determine the growth and behavior of these systems, briefly examines synthetic procedures using bottom-up and top-down fabrication technologies, discusses the sophisticated experimental techniques and state of the art theory results used to characterize the physico-chemical properties of oxide solids and describe the current knowledge concerning key oxide materials with important technological applications.

  10. Oxidation mechanisms occurring in wines

    OpenAIRE

    Oliveira, Carla Maria; Ferreira, António César Silva; Freitas, Victor De; Silva, Artur M. S.

    2011-01-01

    The present review aims to show the state of the art on the oxidation mechanisms occurring in wines, as well as the methods to monitor, classify and diagnose wine oxidation. Wine oxidation can be divided in enzymatic oxidation and non-enzymatic oxidation. Enzymatic oxidation almost entirely occurs in grape must and is largely correlated with the content of hydroxycinnamates, such as caffeoyltartaric acid and paracoumaroyltartaric acid, and flavan-3-ols. Non-enzymatic oxidation, al...

  11. Molecular water oxidation catalysis

    CERN Document Server

    Llobet, Antoni

    2014-01-01

    Photocatalytic water splitting is a promising strategy for capturing energy from the sun by coupling light harvesting and the oxidation of water, in order to create clean hydrogen fuel. Thus a deep knowledge of the water oxidation catalysis field is essential to be able to come up with useful energy conversion devices based on sunlight and water splitting. Molecular Water Oxidation Catalysis: A Key Topic for New Sustainable Energy Conversion Schemes presents a comprehensive and state-of-the-art overview of water oxidation catalysis in homogeneous phase, describing in detail the most importan

  12. Isotopes in oxidation reactions

    International Nuclear Information System (INIS)

    Stewart, R.

    1976-01-01

    The use of isotopes in the study of organic oxidation mechanisms is discussed. The help provided by tracer studies to demonstrate the two-equivalent path - hydride transfer, is illustrated by the examples of carbonium oxidants and the Wacker reaction. The role of kinetic isotope effects in the study of the scission of carbon-hydrogen bonds is illustrated by hydride abstraction, hydrogen atom abstraction, proton abstraction and quantum mechanical tunnelling. Isotopic studies on the oxidation of alcohols, carbonyl compounds, amines and hydrocarbons are discussed. The role of isotopes in the study of biochemical oxidation is illustrated with a discussion on nicotinamide and flavin coenzymes. (B.R.H.)

  13. Rare earth oxide doping in oxide cathodes

    International Nuclear Information System (INIS)

    Engelsen, Daniel den; Gaertner, Georg

    2006-01-01

    The effect on life performance and poisoning with O 2 by doping oxide cathodes with rare earth oxides and pseudo rare earth oxides, notably yttria, is qualitatively explained in terms of electrolysis of BaO during emission of electrons. Doped cathodes show less electrolysis and consume therefore less Ba during life: consequently, doped cathodes have a better life performance. However, the lower Ba-production makes doped cathodes more sensitive to oxygen poisoning. The experimentally found relation between conductivity and yttria concentration was the motive to propose a new model for the crystal imperfections in BaO. In this new imperfection model most Y 3+ -ions will combine with barium vacancies, therefore, the increase of the conductivity is modest and also the effect on the position of the Fermi level is modest. By assuming a combination of bulk and surface conductivity, the agreement between experiment and theory can be improved further

  14. Preparation of uranium-based oxide catalysts; Preparation de catalyseurs oxydes a base d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Bressat, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1965-07-01

    We have studied the thermal decomposition of uranyl and uranium IV oxalates as a mean of producing uranium dioxide. We have isolated the main intermediate phases of the decompositions and have indexed the lines of their X-ray diffraction patterns. The oxides produced by the decomposition are ill-defined and unstable: they strongly absorb atmospheric oxygen with modification of the composition and, in certain cases, of the structure (pyrophoric oxide). With a view to obtaining stable oxides, we have prepared mixed uranium-thorium oxalates. In order to prepare an oxalate having a homogeneous composition, it is necessary to adopt a well-defined preparation method: the addition of solutions of thorium and uranium IV nitrates to a continually saturated oxalic acid solution. The mixed oxide obtained from the thermal decomposition of an oxalate U{sub x}Th{sub 1-x}(C{sub 2}O{sub 4}){sub 2}, 2 H{sub 2}O at 500 C for 24 hours in a current of oxygen leads to a cubic structure which is well-defined both in the bulk and superficially when x is less than 0.35. Above this atomic concentration of uranium, some uranium moves out of the lattice in the form of UO{sub 3} or U{sub 3}O{sub 8} according to the temperature. The mixed oxide is not stoichiometric,(U{sub x}Th{sub 1-x}O{sub 2+y}) and the average degree of oxidation of the uranium varies with the temperature and partial oxygen pressure. The oxides thus formed have a high surface area. By dissolving the mixed oxalates in a concentrated solution of ammonium oxalate, it is possible to deposit the catalyst on a support, but the differences in the solubilities of the thorium and uranium IV oxalates in the ammonium oxalate make it impossible to prepare double salts formed either of thorium and uranium and of ammonium. (author) [French] Nous avons etudie la decomposition thermique des oxalates d'uranyle et d'uranium IV en vue d'aboutir au dioxide d'uranium. Nous avons pu isoler les principales phases intermediaires des decompositions

  15. The bioenergy village - preconditions and consequences of autonomous heat and power supply on the basis of biomass for agricultrue, ecology and lifestyle in rural regions. Final report phase I; Das Bioenergiedorf - Voraussetzungen und Folgen einer eigenstaendigen Waerme- und Stromversorgung durch Biomasse fuer Landwirtschaft, Oekologie und Lebenskultur im laendlichen Raum. Endbericht Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Ruppert, H.; Ahl, C.; Girschner, W.; Krumbein, W.; Marggraf, R.; Scheffer, K.; Schmuck, P. (eds.)

    2003-07-01

    With support from the Federal Minister of Consumer Protection, Nutrition and Agriculture through the Fachagentur Nachwachsende Rohstoffe e.V. (Renewable Fuels Agency), a project group of Goettingen University was able to demonstrate how complete conversion to biomass of heat and power supply can be achieved for a whole village with maximum social acceptance, environmental compatibility, and economic and technical efficiency. This and further projects will provide flexible, generally applicable concepts for wider use and are expected to give new impetus to bioenergy and help reduce CO2 emissions. This documentation presents the results of the first project phase, which lasted from October 2000 through November 2002. After describing the criteria for which the model village was selected, the work carried out by the various scientific disciplines cooperating in the project (environmental geoscience, crop research, soil research, agricultural economy, psychology, sociology and political science) is described, and the current project status is outlined. (orig.) [German] Mit Unterstuetzung des Bundesministeriums fuer Verbraucherschutz, Ernaehrung und Landwirtschaft durch die Fachagentur Nachwachsende Rohstoffe e.V. konnte die Projektgruppe der Universitaet damit beginnen, beispielhaft in einem Dorf zu demonstrieren, wie eine komplette Umstellung der Strom- und Waermeversorgung auf den Energietraeger Biomasse sozial, umweltvertraeglich, wirtschaftlich und technisch erfolgen kann. Auf der Basis dieser konkreten Umstellugsarbeiten und Erfahrungen aus anderen aehnlichen Projekten sollen uebertragbare, flexible Konzepte erarbeitet werden, die der Nutzung der Bioenergie einen deutlichen Auftrieb geben und dadurch auch erhebliche Kohlendioxid-Einsparpotentiale erschliessen koennen. In dieser Dokumentation sind die Ergebnisse der ersten Phase des Projektes 'Das Bioenergiedorf' vom Oktober 2000 bis November 2002 niedergelegt. Es wird zunaechst in einem Ueberblick

  16. Stabilized chromium oxide film

    Science.gov (United States)

    Garwin, Edward L.; Nyaiesh, Ali R.

    1988-01-01

    Stabilized air-oxidized chromium films deposited on high-power klystron ceramic windows and sleeves having a thickness between 20 and 150.ANG. are useful in lowering secondary electron emission yield and in avoiding multipactoring and window failure due to overheating. The ceramic substrate for the film is chosen from alumina, sapphire or beryllium oxide.

  17. Catalyst for Ammonia Oxidation

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a bimetallic catalyst for ammonia oxidation, a method for producing a bimetallic catalyst for ammonia oxidation and a method for tuning the catalytic activity of a transition metal. By depositing an overlayer of less catalytic active metal onto a more catalytic...

  18. Reducible oxide based catalysts

    Science.gov (United States)

    Thompson, Levi T.; Kim, Chang Hwan; Bej, Shyamal K.

    2010-04-06

    A catalyst is disclosed herein. The catalyst includes a reducible oxide support and at least one noble metal fixed on the reducible oxide support. The noble metal(s) is loaded on the support at a substantially constant temperature and pH.

  19. Death from Nitrous Oxide.

    Science.gov (United States)

    Bäckström, Björn; Johansson, Bengt; Eriksson, Anders

    2015-11-01

    Nitrous oxide is an inflammable gas that gives no smell or taste. It has a history of abuse as long as its clinical use, and deaths, although rare, have been reported. We describe two cases of accidental deaths related to voluntary inhalation of nitrous oxide, both found dead with a gas mask covering the face. In an attempt to find an explanation to why the victims did not react properly to oncoming hypoxia, we performed experiments where a test person was allowed to breath in a closed system, with or without nitrous oxide added. Vital signs and gas concentrations as well as subjective symptoms were recorded. The experiments indicated that the explanation to the fact that neither of the descendents had reacted to oncoming hypoxia and hypercapnia was due to the inhalation of nitrous oxide. This study raises the question whether nitrous oxide really should be easily, commercially available. © 2015 American Academy of Forensic Sciences.

  20. RNA modifications by oxidation

    DEFF Research Database (Denmark)

    Poulsen, Henrik E; Specht, Elisabeth; Broedbaek, Kasper

    2012-01-01

    to encompass various classes of novel regulatory RNAs, including, e.g., microRNAs. It is well known that DNA is constantly oxidized and repaired by complex genome maintenance mechanisms. Analogously, RNA also undergoes significant oxidation, and there are now convincing data suggesting that oxidation......The past decade has provided exciting insights into a novel class of central (small) RNA molecules intimately involved in gene regulation. Only a small percentage of our DNA is translated into proteins by mRNA, yet 80% or more of the DNA is transcribed into RNA, and this RNA has been found......, and the consequent loss of integrity of RNA, is a mechanism for disease development. Oxidized RNA is found in a large variety of diseases, and interest has been especially devoted to degenerative brain diseases such as Alzheimer disease, in which up to 50-70% of specific mRNA molecules are reported oxidized, whereas...

  1. Engineering complex oxide interfaces for oxide electronics

    NARCIS (Netherlands)

    Roy, Saurabh

    2015-01-01

    A complex interplay of physics and chemistry in transition metal oxides determines their electronic, magnetic, and ferroic properties enabling a wide range of applications of these materials. BiFeO_3, a canonical multiferroic system exhibits the interesting feature of enhanced conductivity on

  2. Separation of plutonium oxide nanoparticles and colloids

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Richard E.; Skanthakumar, S.; Soderholm, L. [Argonne National Laboratory, IL (United States). Chemical Sciences and Engineering Division

    2011-11-18

    Colloidal plutonium is an important component of Pu aqueous speciation. Pu colloids are problematic in nuclear separations and are a potential transport vector in the environment. Using a mixture of n-octanol and trichloroacetic acid a selective and reversible separation of these particles can be achieved by exploiting their surface reactivity. [German] Kolloidales Plutonium ist ein wichtiger Bestandteil in waessrigen Pu-Bereitungen. Pu-Kolloide sind problematisch bei der Wiederaufbereitung von Kernmaterial und bilden einen potenziellen Transportvektor in die Umwelt. Mit einem Loesungsmittelgemisch aus n-Octanol und Trichloressigsaeure gelingt die selektive und reversible Trennung dieser Partikel durch Ausnutzung ihrer Oberflaechenreaktivitaet.

  3. Protein oxidation in aquatic foods

    DEFF Research Database (Denmark)

    Baron, Caroline P.

    2014-01-01

    The chapter discusses general considerations about protein oxidation and reviews the mechanisms involved in protein oxidation and consequences of protein oxidation on fish proteins. It presents two case studies, the first deals with protein and lipid oxidation in frozen rainbow trout......, and the second with oxidation in salted herring. The mechanisms responsible for initiation of protein oxidation are unclear, but it is generally accepted that free radical species initiating lipid oxidation can also initiate protein oxidation. The chapter focuses on interaction between protein and lipid...... oxidation. The protein carbonyl group measurement is the widely used method for estimating protein oxidation in foods and has been used in fish muscle. The chapter also talks about the impact of protein oxidation on protein functionality, fish muscle texture, and food nutritional value. Protein oxidation...

  4. Oxidation of uraninite

    International Nuclear Information System (INIS)

    Janeczek, J.; Ewing, R.C.

    1993-06-01

    Samples of uraninite and pitchblende annealed at 1200 degrees C in H 2 , and untreated pitchblende were sequentially oxidized in air at 180-190 degrees C, 230 degrees C, and 300 degrees C. Uraninite and untreated pitchblende oxidized to the U 4 O 9 -type oxide, and their x-ray symmetry remained isometric up to 300 degrees C. Reduced pitchblende, after oxidation to UO 2+x and U 4 O 9 -type oxides, transformed into α-U 3 O 8 at 300 degrees C. Two major mechanisms control uraninite and untreated pitchblende stability during oxidation: 1. Th and/or lanthanide elements maintain charge balance and block oxygen interstitials near impurity cations; 2. the uraninite structure saturates with respect to excess and radiation-induced oxygen interstitials. Untreated pitchblende during oxidation behaved similarly to irradiated UO 2 in spent nuclear fuel; whereas, reduced pitchblende resembled non-irradiated UO 2 . An analysis of the data in the literature, as well as our own efforts (XRD, EMPA, SEM, AEM) to identify U 3 O 7 in samples form Cigar Lake, Canada, failed to provide conclusive evidence of the natural occurrence of tetragonal αU 3 O 7 . Most probably, reported occurrences of U 3 O 7 are mixtures of isometric uraninites of slightly different compositions, 45 refs

  5. Détermination de la composition chimique partielle des graines de trois cultivars de Psophocarpus tetragonolobus (L. DC

    Directory of Open Access Journals (Sweden)

    Lukoki, L.

    1987-01-01

    Full Text Available Determination of some chemical constituents of seeds of three Psophocarpus tetragonolobus cultivars. Studies have been conducted to establish the nutritional characteristics of three cultivars of the winged bean (Psophocarpus tetragonolobus (L. DC. Protein, lipid, amino acids and mineral compositions of the beans have been determined. The protein and fat contents were 37 to 40 % and 16 to 22 % respectively. Defatted beans meal had a very high protein content (47-49 %. The average mineral levels in the seeds, expressed as g/kg DM, were 6.6g, 1.6g, 0.08g and 0.06g for phosphorus, calcium, iron and zinc respectively. The amino acids profile revealed very high levels of aspartic acid, glutamic acid, lysine, arginine, leucine and threonine as compared to these of soybean protein. Sulfur amino acids levels are low.

  6. German RPV safety assessment. Underpinning of the procedure by complementary test results measured in the hot cells; Der deutsche RDB-Sicherheitsnachweis. Untermauerung der Vorgehensweise durch ergaenzende Kennwertermittlung in den Heissen Zellen

    Energy Technology Data Exchange (ETDEWEB)

    Keim, Elisabeth; Hein, Hieronymus; Gundermann, Arnulf [AREVA NP GmbH (Germany); Hoffmann, Harald [VGB (Germany); Koenig, Guenter; Ilg, Ulf [EnBW (Germany); Nagel, Gerhard [e-on Kernkraft (Germany); Widera, Martin [RWE (Germany); Rebsamen, Daniel [KKW Goesgen (Germany)

    2008-07-01

    , um beide Konzepte miteinander vergleichen zu koennen. Die Auswertung der generierten Datenbasis fuehrte zu folgenden wesentlichen Ergebnissen des Vorhabens: -Die ''lower bound'' ASME K{sub Ic}-Kurve fuer Rissinitiierung (Sprodbruchversagen) konnte durch die gemessenen Bruchzaehigkeitswerte fuer den bestrahlten Werkstoffzustand bestaetigt werden. -Der signifikante Einfluss der Legierungselemente Kupfer und Nickel auf das Bestrahlungsverhalten von RDB-Werkstoffen wurde mit beiden Konzepten bestaetigt. -Die Uebergangstemperaturverschiebungen beider Konzepte {delta}T{sub 41} und {delta}T{sub 0} korrelieren relativ gut miteinander. -Bruchmechanikproben vom Typ SE(B) 10 mm x 10 mm sind fuer die T{sub 0}-Bestimmung geeignet und ergeben tendenziell etwas niedrigere T{sub 0}-Werte als Kompakt-Proben. -Die gemessenen Crack Arrest Zaehigkeitswerte werden weitestgehend von der ''lower bound'' ASME K{sub Ia}-Kurve eingehuellt. (orig.)

  7. Reduction of radiation exposure in PET examinations by data acquisition in the 3D mode; Reduktion der Strahlenexposition bei PET-Untersuchungen durch Datenakquisition im 3D-Modus

    Energy Technology Data Exchange (ETDEWEB)

    Brix, G. [Bundesamt fuer Strahlenschutz, Neuherberg (Germany). Inst. fuer Strahlenhygiene]|[Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Adam, L.E. [Department of Radiology, Philadelphia, PA (United States). Div. of Nuclear Medicine; Zaers, J.; Trojan, H.; Doll, J. [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Bellemann, M.E. [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie]|[Fachhochschule Jena (Germany). Fachbereich Medizintechnik; Nosske, D. [Bundesamt fuer Strahlenschutz, Neuherberg (Germany). Inst. fuer Strahlenhygiene

    1999-04-01

    , auf die abschirmende Wirkung von Septen zwischen den einzelnen Detektorringen (2D-Modus) zu verzichten, so dass auch koinzidente Ereignisse zwischen Detektoren auf weiter entfernt liegenden Ringen erfasst werden koennen (3D-Modus). Ziel der vorliegenden Arbeit war es, das Zaehlratenverhalten eines PET-Scanners der neuesten Generation im 2D- und im 3D-Modus anhand von Phantommessungen zu untersuchen und die sich daraus ergebenden Konsequenzen fuer die Strahlenhygiene bei PET-Untersuchungen mit 2-[F-18]-Fluor-2-Desoxyglukose (F-18-FDG) zu diskutieren. Methoden: Alle Messungen wurden am Ganzkoerper-PET-System ECAT EXACT HR{sup +} durchgefuehrt. Fuer die 2D-Messungen wurde ein Kollimator aus duennen Wolframlamellen in das Gesichtsfeld eingebracht. Das Zaehlratenverhalten des Scanners wurde dem NEMA-Protokoll folgend ueber einen weiten Bereich von F-18-Aktivitaetskonzentrationen untersucht. Darueber hinaus wurden PET-Aufnahmen des EEC-Ganzkoerperphantoms mit verschiedenen Einsaetzen im 2D- und im 3D-Modus jeweils ueber 15 min akquiriert, wobei die F-18-Aktivitaetskonzentrationen bei der 3D-Messung halb so hoch waren wie bei der 2D-Messung. Ergebnisse: Fuer das zylinderfoermige NEMA-Phantom (Durchmesser=19,4 cm, Laenge=19,0 cm) ergab sich im 3D-Modus eine im Vergleich zur 2D-Akquisition etwa fuenffach hoehere Systemsensitivitaet (27,7 statt 5,7 cps/Bq/ml). Die Auswertung der rekonstruierten Aktivitaetsverteilungen des EEC-Phantoms ergab, dass die Qualitaet der aus dem 3D-Projektionsdatensatz berechneten PET-Aufnahmen besser war als die der korrespondierenden 2D-Aufnahmen, obwohl die Aktivitaetskonzentrationen nur halb so hoch waren. Schlussfolgerungen: Durch die Datenakquisition im 3D-Modus kann die zu applizierende Aktivitaetsmenge bei gleichzeitiger Verbesserung der Bildqualitaet erheblich reduziert werden. Fuer Patientenuntersuchungen mit F-18-FDG im Ganzkoerperbereich reicht es unserer Erfahrung nach aus, eine Aktivitaet zwischen 150 und 200 MBq zu applizieren. Dies

  8. Recovery of vanadium oxide

    International Nuclear Information System (INIS)

    Bates, C.P.; Clark, N.E.

    1985-01-01

    This invention relates to the recovery of vanadium oxide from molten metal. The invention provides a method for recovering vanadium oxide from molten metal, which includes passing oxygen and at least one coolant gas or shroud into the molten metal by way of at least one elongate lance. The invention also provides an arrangement for the recovery of vanadium oxide from molten metal, which includes at least one elongate lance extending into the molten metal. The lance is provided with at least one elongate bore extending therethrough. Means are provided to allow at least oxygen and at least one coolant gas to pass through the lance and into the molten metal

  9. High Current Oxide Cathodes

    National Research Council Canada - National Science Library

    Luhmann, N

    2000-01-01

    The aim of the AASERT supported research is to develop the plasma deposition/implantation process for coating barium, strontium and calcium oxides on nickel substrates and to perform detailed surface...

  10. Markers of protein oxidation

    DEFF Research Database (Denmark)

    Headlam, Henrietta A; Davies, Michael Jonathan

    2004-01-01

    Exposure of proteins to radicals in the presence of O2 gives both side-chain oxidation and backbone fragmentation. These processes can be interrelated, with initial side-chain oxidation giving rise to backbone damage via transfer reactions. We have shown previously that alkoxyl radicals formed...... of this process depends on the extent of oxidation at C-3 compared with other sites. HO*, generated by gamma radiolysis, gave the highest total carbonyl yield, with protein-bound carbonyls predominating over released. In contrast, metal ion/H2O2 systems, gave more released than bound carbonyls, with this ratio...... modulated by EDTA. This is ascribed to metal ion-protein interactions affecting the sites of initial oxidation. Hypochlorous acid gave low concentrations of released carbonyls, but high yields of protein-bound material. The peroxyl radical generator 2,2'-azobis(2-amidinopropane) hydrochloride...

  11. Oxidizer in phosphoric reactors

    International Nuclear Information System (INIS)

    Santos Benedetto, J. dos

    1985-01-01

    Oxidation during the manufacture of wet-process phosphoric acid affected the distribution of uranium and impurities between phosphoric acid and gypsum, by decreasing the uranium loss to gypsum and the impurities solubilization in phosphoric acid. (Author) [pt

  12. Single sheet iron oxides

    DEFF Research Database (Denmark)

    Yin, Zhou

    profile with reversible reduction and oxidation, suggesting the formation of FeII-OH/O-FeIII clusters as that in GRs were formed on the ITO electrode (trichloroethylene (TCE), tetrachloride (CT) and 4-chlorophenol are used to test...

  13. High Current Oxide Cathodes

    National Research Council Canada - National Science Library

    Luhmann, N

    2000-01-01

    .... The vacuum are plasma deposition gun developed at Lawrence Berkeley National Laboratory (LBNL) has been used to deposit oxides and nitrides with very precise control over deposition rate and composition.

  14. Titanium oxide fever

    International Nuclear Information System (INIS)

    De Jonge, D.; Visser, J.

    2012-01-01

    One measure to improve air quality is to apply photo-catalytic substances that capture NOx onto the road surface or onto baffle boards alongside the roads. The effect of titanium oxide containing clinkers with coating was discussed in the report 'Demonstration project of air-purifying pavement in Hengelo, The Netherlands' that was published in May 2011. This article examines the way in which the effectiveness of this study was determined. Can titanium oxide containing clinkers and coatings indeed capture NOx?. [nl

  15. Metal atom oxidation laser

    International Nuclear Information System (INIS)

    Jensen, R.J.; Rice, W.W.; Beattie, W.H.

    1975-01-01

    A chemical laser which operates by formation of metal or carbon atoms and reaction of such atoms with a gaseous oxidizer in an optical resonant cavity is described. The lasing species are diatomic or polyatomic in nature and are readily produced by exchange or other abstraction reactions between the metal or carbon atoms and the oxidizer. The lasing molecules may be metal or carbon monohalides or monoxides

  16. Chemistry of phospholipid oxidation.

    Science.gov (United States)

    Reis, Ana; Spickett, Corinne M

    2012-10-01

    The oxidation of lipids has long been a topic of interest in biological and food sciences, and the fundamental principles of non-enzymatic free radical attack on phospholipids are well established, although questions about detail of the mechanisms remain. The number of end products that are formed following the initiation of phospholipid peroxidation is large, and is continually growing as new structures of oxidized phospholipids are elucidated. Common products are phospholipids with esterified isoprostane-like structures and chain-shortened products containing hydroxy, carbonyl or carboxylic acid groups; the carbonyl-containing compounds are reactive and readily form adducts with proteins and other biomolecules. Phospholipids can also be attacked by reactive nitrogen and chlorine species, further expanding the range of products to nitrated and chlorinated phospholipids. Key to understanding the mechanisms of oxidation is the development of advanced and sensitive technologies that enable structural elucidation. Tandem mass spectrometry has proved invaluable in this respect and is generally the method of choice for structural work. A number of studies have investigated whether individual oxidized phospholipid products occur in vivo, and mass spectrometry techniques have been instrumental in detecting a variety of oxidation products in biological samples such as atherosclerotic plaque material, brain tissue, intestinal tissue and plasma, although relatively few have achieved an absolute quantitative analysis. The levels of oxidized phospholipids in vivo is a critical question, as there is now substantial evidence that many of these compounds are bioactive and could contribute to pathology. The challenges for the future will be to adopt lipidomic approaches to map the profile of oxidized phospholipid formation in different biological conditions, and relate this to their effects in vivo. This article is part of a Special Issue entitled: Oxidized phospholipids

  17. Thin zirconium oxides

    International Nuclear Information System (INIS)

    Oviedo, Cristina

    2000-01-01

    Polycrystalline Zr and two pure Zr single-crystal samples, one oriented with the normal to the surface parallel to the c-axis of the hcp structure (Z1) and the other with the normal perpendicular to c (Z2), were oxidised at 10 -8 , 10 -7 and 10 -6 Torr and room temperature. Oxidation kinetics, composition and thicknesses of the oxide films formed in each case were analyzed using XPS (X-ray Photoelectron Spectroscopy) as the main technique. The oxidation kinetics followed logarithmic laws in all cases. The deconvolution of XPS Zr3d peaks indicated the formation of two Zr-O compounds before the formation of ZrO 2 . Varying the photoelectrons take-off angle, the compound distribution inside the oxide films could be established. Thus, it was confirmed that the most external oxide, in contact with the gas, was ZrO 2 . The thickness of the films grown at the different pressures was determined. In the polycrystalline samples, thicknesses between 15 and 19 ± 2Angstroem were obtained for pressures between 10 -8 and 10 -6 Torr, in close coincidence with the determined ones for Z2. The thicknesses measured in Z1 were smaller, reaching 13 ± 2Angstroem for the oxidations performed at 10 -6 Torr. (author)

  18. Does oxidative stress shorten telomeres?

    NARCIS (Netherlands)

    Boonekamp, Jelle J.; Bauch, Christina; Mulder, Ellis; Verhulst, Simon

    Oxidative stress shortens telomeres in cell culture, but whether oxidative stress explains variation in telomere shortening in vivo at physiological oxidative stress levels is not well known. We therefore tested for correlations between six oxidative stress markers and telomere attrition in nestling

  19. Electrochemistry of hydrous oxide films

    International Nuclear Information System (INIS)

    Burke, L.D.; Lyons, M.E.G.

    1986-01-01

    The formation, acid-base properties, structural aspects, and transport processes of hydrous oxide films are discussed. Classical and nonclassical theoretical models of the oxide-solution interface are compared. Monolayer oxidation, behavior, and crystal growth of oxides on platinum, palladium, gold, iridium, rhodium, ruthenium, and some non-noble metals, including tungsten, are reviewed and compared

  20. Porous ceramics out of oxides

    International Nuclear Information System (INIS)

    Bakunov, V.S.; Balkevich, V.L.; Vlasov, A.S.; Guzman, I.Ya.; Lukin, E.S.; Poluboyarinov, D.N.; Poliskij, R.Ya.

    1977-01-01

    A review is made of manufacturing procedures and properties of oxide ceramics intended for high-temperature thermal insulation and thermal protection applications. Presented are structural characteristics of porous oxide refractories and their properties. Strength and thermal conductivity was shown to depend upon porosity. Described is a procedure for manufacturing porous ceramic materials from aluminium oxide, zirconium dioxide, magnesium oxide, beryllium oxide. The thermal resistance of porous ceramics from BeO is considerably greater than that of other high-refractoriness oxides. Listed are areas of application for porous materials based on oxides

  1. Staphylococcal response to oxidative stress

    Directory of Open Access Journals (Sweden)

    Rosmarie eGaupp

    2012-03-01

    Full Text Available Staphylococci are a versatile genus of bacteria that are capable of causing acute and chronic infections in diverse host species. The success of staphylococci as pathogens is due in part to their ability to mitigate endogenous and exogenous oxidative and nitrosative stress. Endogenous oxidative stress is a consequence of life in an aerobic environment; whereas, exogenous oxidative and nitrosative stress are often due to the bacteria’s interaction with host immune systems. To overcome the deleterious effects of oxidative and nitrosative stress, staphylococci have evolved protection, detoxification, and repair mechanisms that are controlled by a network of regulators. In this review, we summarize the cellular targets of oxidative stress, the mechanisms by which staphylococci sense oxidative stress and damage, oxidative stress protection and repair mechanisms, and regulation of the oxidative stress response. When possible, special attention is given to how the oxidative stress defense mechanisms help staphylococci control oxidative stress in the host.

  2. Protein oxidation and peroxidation

    DEFF Research Database (Denmark)

    Davies, Michael Jonathan

    2016-01-01

    Proteins are major targets for radicals and two-electron oxidants in biological systems due to their abundance and high rate constants for reaction. With highly reactive radicals damage occurs at multiple side-chain and backbone sites. Less reactive species show greater selectivity with regard...... to the residues targeted and their spatial location. Modification can result in increased side-chain hydrophilicity, side-chain and backbone fragmentation, aggregation via covalent cross-linking or hydrophobic interactions, protein unfolding and altered conformation, altered interactions with biological partners...... and modified turnover. In the presence of O2, high yields of peroxyl radicals and peroxides (protein peroxidation) are formed; the latter account for up to 70% of the initial oxidant flux. Protein peroxides can oxidize both proteins and other targets. One-electron reduction results in additional radicals...

  3. Bacterium oxidizing carbon monoxide

    Energy Technology Data Exchange (ETDEWEB)

    Kistner, A

    1953-01-01

    Present-day knowledge of the microbiological oxidation of carbon monoxide is based on doubtful observations and imperfect experimental procedures. By making use of shake cultures in contact with gas mixtures containing high concentrations of CO and by employing liquid enrichment media with a low content of organic matter and solid media of the same composition with not more than 1.2% agar, it proved possible to isolate a co-oxidizing bacterium of the genus hydrogenomonas from sewage sludge. For the first time irrefutable proof has been given of the oxidation of carbon monoxide by a pure culture of a bacterium, both in growing cultures and in resting cell suspensions. 12 references.

  4. Zircaloy oxidation studies

    International Nuclear Information System (INIS)

    Prater, J.T.; Beauchamp, R.H.; Saenz, N.T.

    1985-06-01

    The oxidation kinetics of Zircaloy-4 in steam have been determined at 1300-2400 0 C. Growth of the ZrO 2 and α-Zr layers display parabolic behavior over the entire temperature range studied. A discontinuity in the oxidation kinetics at 1510 0 C causes rates to increase above those previously established by the Baker-Just relationship. This increase coincides with the tetragonal-to-cubic phase transformation in ZrO/sub 2-x/. No discontinuity in the oxide growth rate is observed upon melting of Zr(0). The effects of temperature gradients have been taken into account and corrected values representative of near-isothermal conditions have been computed

  5. Oxidative Tritium Decontamination System

    International Nuclear Information System (INIS)

    Gentile, Charles A.; Parker, John J.; Guttadora, Gregory L.; Ciebiera, Lloyd P.

    2002-01-01

    The Princeton Plasma Physics Laboratory, Tritium Systems Group has developed and fabricated an Oxidative Tritium Decontamination System (OTDS), which is designed to reduce tritium surface contamination on various components and items. The system is configured to introduce gaseous ozone into a reaction chamber containing tritiated items that require a reduction in tritium surface contamination. Tritium surface contamination (on components and items in the reaction chamber) is removed by chemically reacting elemental tritium to tritium oxide via oxidation, while purging the reaction chamber effluent to a gas holding tank or negative pressure HVAC system. Implementing specific concentrations of ozone along with catalytic parameters, the system is able to significantly reduce surface tritium contamination on an assortment of expendable and non-expendable items. This paper will present the results of various experimentation involving employment of this system

  6. Design criteria for crankshafts - axial slide bearing in Otto and diesel engines by means of computer-based simulations and experimental investigations. Axial slide bearing design - final report; Auslegungskriterien fuer Kurbelwellen - Axialgleitlager in Otto- und Dieselmotoren durch rechnergestuetzte Simulation und experimentelle Untersuchungen. Axialgleitlagerauslegung - Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Backhaus, K. [Univ. GH Kassel (Germany). Inst. fuer Maschinenelemente und Konstruktionstechnik; Hunsicker, W. [Fachhochschule Mannheim (Germany). Inst. fuer Tribologie; Schubert, W. [KS Gleitlager GmbH, St. Leon-Rot (Germany)

    2003-07-01

    In the frame of this research project a simulation program has been developed in order to investigate suspension pressure build-up in crankshaft axial bearings taking into account mixed friction conditions. The investigated system is performing in a dynamic way taking into account the engine dynamics. Based upon the high engineering state of radial slide bearings, axial bearings as well as conical slide faces with any conical angle can be simulated in the same way. The solid body contact share in the system to be investigated is taken into account by the integral effect of the real microscopic surface structure on microhydrodynamics and contact pressure build-up. The influence of individual parameters, as e.g. macro-geometric bearing surface design can be investigated by means of simulation results. Wavy stopping faces and bearing surfaces with Rayleigh-steps are characterised by high hydrodynamic supporting pressure magnitudes in terms of macrogeometry. Elasto-hydrodynamic investigations at one stop collar and under engine-specific load on stop disks of a base bearing show the influence of structure elasticity and prove the necessity to consider them when the individual systems are analysed. (orig.) [German] Im Rahmen des durchgefuehrten Forschungsvorhabens wurde ein Simulationsprogramm zur Untersuchung des Tragdruckaufbaus in Kurbelwellen-Axiallagern unter Beruecksichtigung von Mischreibungszustaenden entwickelt. Das untersuchte System verhaelt sich dabei unter Beruecksichtigung der Motordynamik dynamisch. Ausgehend von dem hohen Entwicklungsstand von Radialgleitlagern koennen Axiallager sowie kegelfoermige Gleitflaechen mit beliebigen Kegelwinkeln in gleicher Weise simuliert werden. Dem hohen Festkoerperkontaktanteil in dem zu untersuchenden System wird durch die Beruecksichtigung der integralen Wirkung der realen mikroskopischen Oberflaechenstruktur auf Mikrohydrodynamik und Kontaktdruckaufbau Rechnung getragen. Anhand von Simulationsergebnissen kann der

  7. Krypton oxides under pressure.

    Science.gov (United States)

    Zaleski-Ejgierd, Patryk; Lata, Pawel M

    2016-02-02

    Under high pressure, krypton, one of the most inert elements is predicted to become sufficiently reactive to form a new class of krypton compounds; krypton oxides. Using modern ab-initio evolutionary algorithms in combination with Density Functional Theory, we predict the existence of several thermodynamically stable Kr/O species at elevated pressures. In particular, our calculations indicate that at approx. 300 GPa the monoxide, KrO, should form spontaneously and remain thermo- and dynamically stable with respect to constituent elements and higher oxides. The monoxide is predicted to form non-molecular crystals with short Kr-O contacts, typical for genuine chemical bonds.

  8. Sintering of beryllium oxide

    International Nuclear Information System (INIS)

    Caillat, R.; Pointud, R.

    1955-01-01

    This study had for origin to find a process permitting to manufacture bricks of beryllium oxide of pure nuclear grade, with a density as elevated as possible and with standardized shape. The sintering under load was the technique kept for the manufacture of the bricks. Because of the important toxicity of the beryllium oxide, the general features for the preliminary study of the sintering, have been determined while using alumina. The obtained results will be able to act as general indication for ulterior studies with sintering under load. (M.B.) [fr

  9. Preparation of uranium-based oxide catalysts; Preparation de catalyseurs oxydes a base d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Bressat, R. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1965-07-01

    We have studied the thermal decomposition of uranyl and uranium IV oxalates as a mean of producing uranium dioxide. We have isolated the main intermediate phases of the decompositions and have indexed the lines of their X-ray diffraction patterns. The oxides produced by the decomposition are ill-defined and unstable: they strongly absorb atmospheric oxygen with modification of the composition and, in certain cases, of the structure (pyrophoric oxide). With a view to obtaining stable oxides, we have prepared mixed uranium-thorium oxalates. In order to prepare an oxalate having a homogeneous composition, it is necessary to adopt a well-defined preparation method: the addition of solutions of thorium and uranium IV nitrates to a continually saturated oxalic acid solution. The mixed oxide obtained from the thermal decomposition of an oxalate U{sub x}Th{sub 1-x}(C{sub 2}O{sub 4}){sub 2}, 2 H{sub 2}O at 500 C for 24 hours in a current of oxygen leads to a cubic structure which is well-defined both in the bulk and superficially when x is less than 0.35. Above this atomic concentration of uranium, some uranium moves out of the lattice in the form of UO{sub 3} or U{sub 3}O{sub 8} according to the temperature. The mixed oxide is not stoichiometric,(U{sub x}Th{sub 1-x}O{sub 2+y}) and the average degree of oxidation of the uranium varies with the temperature and partial oxygen pressure. The oxides thus formed have a high surface area. By dissolving the mixed oxalates in a concentrated solution of ammonium oxalate, it is possible to deposit the catalyst on a support, but the differences in the solubilities of the thorium and uranium IV oxalates in the ammonium oxalate make it impossible to prepare double salts formed either of thorium and uranium and of ammonium. (author) [French] Nous avons etudie la decomposition thermique des oxalates d'uranyle et d'uranium IV en vue d'aboutir au dioxide d'uranium. Nous avons pu isoler les principales phases

  10. Catalytic Oxidation of Cyanogen Chloride over a Monolithic Oxidation Catalyst

    National Research Council Canada - National Science Library

    Campbell, Jeffrey

    1997-01-01

    The catalytic oxidation of cyanogen chloride was evaluated over a monolithic oxidation catalyst at temperatures between 200 and 300 deg C in air employing feed concentrations between 100 and 10,000 ppm...

  11. Uranium oxidation: characterization of oxides formed by reaction with water

    International Nuclear Information System (INIS)

    Fuller, E.L. Jr.; Smyrl, N.R.; Condon, J.B.; Eager, M.H.

    1983-01-01

    Three different uranium oxide samples have been characterized with respect to the different preparation techniques. Results show that the water reaction with uranium metal occurs cyclically forming laminar layers of oxide which spall off due to the strain at the oxide/metal interface. Single laminae are released if liquid water is present due to the prizing penetration at the reaction zone. The rate of reaction of water with uranium is directly proportional to the amount of adsorbed water on the oxide product. Rapid transport is effected through the open hydrous oxide product. Dehydration of the hydrous oxide irreversibly forms a more inert oxide which cannot be rehydrated to the degree that prevails in the original hydrous product of uranium oxidation with water. 27 figures

  12. Green oxidations: Titanium dioxide induced tandem oxidation coupling reactions

    OpenAIRE

    Jeena, Vineet; Robinson, Ross S

    2009-01-01

    Summary The application of titanium dioxide as an oxidant in tandem oxidation type processes is described. Under microwave irradiation, quinoxalines have been synthesized in good yields from the corresponding ?-hydroxyketones.

  13. Compliance with future emission standards of mobile machines by developing a monovalent natural gas combustion process; Einhaltung zukuenftiger Abgasnormen von mobilen Arbeitsmaschinen durch Entwicklung eines monovalenten Erdgas-Brennverfahrens

    Energy Technology Data Exchange (ETDEWEB)

    Prehn, Sascha [Rostock Univ. (Germany). Lehrstuhl fuer Kolbenmaschinen und Verbrennungsmotoren; Wichmann, Volker; Harndorf, Horst; Beberdick, Wolfgang

    2014-08-01

    Within the presented project a monovalent natural gas engine is being developed. Based on a serial diesel engine the operation mode of this prototype is changed to a spark ignition concept. The long term purpose of this new engine is an agricultural application. One major objective of the project is the investigation and evaluation of a combustion process, able to fulfil the performance requests as well as the European emission limits for nitrogen oxides NO{sub x}, and carbon monoxide CO of mobile machinery, which become into law in October 2014 (EU stage IV). At the time there are no legislative regulations existing regarding the methane emissions of the observed engines. To get a benefit in greenhouse gas emissions compared to diesel or gasoline engines the methane emissions have to be minimized while operating in natural gas mode. In the course of the current project an engine operation with a methane emission less than 0.5 g/kWh (representing the EURO VI limit for heavy duty vehicles) could be demonstrated. In contrast to diesel engines for agricultural applications it is possible to comply with the emission standards without using a high sophisticated after treatment system consisting of diesel oxidation catalyst (DOC), particulate filter (DPF) and SCR catalyst. The usage of a three way catalyst optimized for high methane conversions is sufficient for a stoichiometry gas operation with exhaust gas recirculation. Therefore a significant cost advantage is given.

  14. Oxidation of methyl heterocyclic compounds on vanadium oxide catalysts

    International Nuclear Information System (INIS)

    Shimanskaya, M.V.; Lejtis, L.A.; Iovel', I.G.; Gol'dberg, Yu.Sh.; Skolmejstere, R.A.; Golender, L.O.

    1985-01-01

    Data on vapor-phase oxidation of methyl derivatives of thiophene, Δ 2 - thiazo line, pyridine, pyrazine and pyramidine on oxide vanadium-molybdenum catalysts to corresponding heterylaldehydes are generalized. The dependence of catalytic properties of oxide vanadium-molybdenum systems in oxidation reactions of methylheterocyclic compounds on V:Mo ratio in the catalyst is revealed. It is shown that heterocyclic compounds are coordinated by a heteroatom on Lewis centres of V-Mo-O-catalyst primarily with partially reduced vanadium ions

  15. Improved Understanding of In Situ Chemical Oxidation Contaminant Oxidation Kinetics

    Science.gov (United States)

    2007-12-01

    natural oxidant demand •OH hydroxide radical Ox oxidant O3 ozone PCE perchloroethylene HSO5− peroxymonosulfate PNDA p...properties (e.g., soil mineralogy , natural carbon content) affect oxidant mobility and stability in the subsurface, and develop a standardized natural...chlorinated ethenes For contaminant oxidation by activated S2O82−, it is more difficult to develop a general description of kobs vs. T because there are

  16. Iron oxides photochemical dissolution

    International Nuclear Information System (INIS)

    Blesa, M.A.; Litter, M.I.

    1987-01-01

    This work was intended to study the light irradiation influence of diverse wave-lengths on iron oxides dissolution in aqueous solutions. The objectives of this work were: the exploration of photochemical processes with the aim of its eventual application in: a) decontamination and chemical cleaning under special conditions; b) materials for solar energy conversion. (Author)

  17. Highly oxidized superconductors

    Science.gov (United States)

    Morris, Donald E.

    1994-01-01

    Novel superconducting materials in the form of compounds, structures or phases are formed by performing otherwise known syntheses in a highly oxidizing atmosphere rather than that created by molecular oxygen at atmospheric pressure or below. This leads to the successful synthesis of novel superconducting compounds which are thermodynamically stable at the conditions under which they are formed.

  18. Oxidative Stress in Myopia

    Directory of Open Access Journals (Sweden)

    Bosch-Morell Francisco

    2015-01-01

    Full Text Available Myopia affected approximately 1.6 billion people worldwide in 2000, and it is expected to increase to 2.5 billion by 2020. Although optical problems can be corrected by optics or surgical procedures, normal myopia and high myopia are still an unsolved medical problem. They frequently predispose people who have them to suffer from other eye pathologies: retinal detachment, glaucoma, macular hemorrhage, cataracts, and so on being one of the main causes of visual deterioration and blindness. Genetic and environmental factors have been associated with myopia. Nevertheless, lack of knowledge in the underlying physiopathological molecular mechanisms has not permitted an adequate diagnosis, prevention, or treatment to be found. Nowadays several pieces of evidence indicate that oxidative stress may help explain the altered regulatory pathways in myopia and the appearance of associated eye diseases. On the one hand, oxidative damage associated with hypoxia myopic can alter the neuromodulation that nitric oxide and dopamine have in eye growth. On the other hand, radical superoxide or peroxynitrite production damage retina, vitreous, lens, and so on contributing to the appearance of retinopathies, retinal detachment, cataracts and so on. The objective of this review is to suggest that oxidative stress is one of the key pieces that can help solve this complex eye problem.

  19. Wet oxidation of quinoline

    DEFF Research Database (Denmark)

    Thomsen, A.B.; Kilen, H.H.

    1998-01-01

    The influence of oxygen pressure (0.4 and 2 MPa). reaction time (30 and 60 min) and temperature (260 and 280 degrees C) on the wet oxidation of quinoline has been studied. The dominant parameters for the decomposition of quinoline were oxygen pressure and reaction temperature. whereas the reactio...

  20. Solid Oxide Fuel Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The solid oxide fuel cell comprising a metallic support material, an active anode layer consisting of a good hydrocarbon cracking catalyst, an electrolyte layer, an active cathode layer, and a transition layer consisting of preferably a mixture of LSM and a ferrite to the cathode current collector...

  1. Dopamine Oxidation and Autophagy

    Directory of Open Access Journals (Sweden)

    Patricia Muñoz

    2012-01-01

    Full Text Available The molecular mechanisms involved in the neurodegenerative process of Parkinson's disease remain unclear. Currently, there is a general agreement that mitochondrial dysfunction, α-synuclein aggregation, oxidative stress, neuroinflammation, and impaired protein degradation are involved in the neurodegeneration of dopaminergic neurons containing neuromelanin in Parkinson's disease. Aminochrome has been proposed to play an essential role in the degeneration of dopaminergic neurons containing neuromelanin by inducing mitochondrial dysfunction, oxidative stress, the formation of neurotoxic α-synuclein protofibrils, and impaired protein degradation. Here, we discuss the relationship between the oxidation of dopamine to aminochrome, the precursor of neuromelanin, autophagy dysfunction in dopaminergic neurons containing neuromelanin, and the role of dopamine oxidation to aminochrome in autophagy dysfunction in dopaminergic neurons. Aminochrome induces the following: (i the formation of α-synuclein protofibrils that inactivate chaperone-mediated autophagy; (ii the formation of adducts with α- and β-tubulin, which induce the aggregation of the microtubules required for the fusion of autophagy vacuoles and lysosomes.

  2. Plutonium oxide dissolution

    International Nuclear Information System (INIS)

    Gray, J.H.

    1992-01-01

    Several processing options for dissolving plutonium oxide (PuO 2 ) from high-fired materials have been studied. The scoping studies performed on these options were focused on PuO 2 typically generated by burning plutonium metal and PuO 2 produced during incineration of alpha contaminated waste. At least two processing options remain applicable for dissolving high-fired PuO 2 in canyon dissolvers. The options involve solid solution formation of PuO 2 With uranium oxide (UO 2 ) and alloying incinerator ash with aluminum. An oxidative dissolution process involving nitric acid solutions containing a strong oxidizing agent, such as cerium (IV), was neither proven nor rejected. This uncertainty was due to difficulty in regenerating cerium (IV) ions during dissolution. However, recent work on silver-catalyzed dissolution of PuO 2 with persulfate has demonstrated that persulfate ions regenerate silver (II). Use of persulfate to regenerate cerium (IV) or bismuth (V) ions during dissolution of PuO 2 materials may warrant further study

  3. Aqueous polyethylene oxide solutions

    International Nuclear Information System (INIS)

    Breen, J.

    1987-01-01

    A number of aspects concerning the reorientation of polymer, water and ion hydration complexes have been studied in aqueous solution of polyethylene oxide (PEO). The polymer dynamics are investigated by 1 H-PEO and 13 C-PEO nuclear relaxation experiments. 162 refs.; 30 figs.; 19 tabs

  4. Nitric oxide: a physiologic messenger.

    Science.gov (United States)

    Lowenstein, C J; Dinerman, J L; Snyder, S H

    1994-02-01

    To review the physiologic role of nitric oxide, an unusual messenger molecule that mediates blood vessel relaxation, neurotransmission, and pathogen suppression. A MEDLINE search of articles published from 1987 to 1993 that addressed nitric oxide and the enzyme that synthesizes it, nitric oxide synthase. Animal and human studies were selected from 3044 articles to analyze the clinical importance of nitric oxide. Descriptions of the structure and function of nitric oxide synthase were selected to show how nitric oxide acts as a biological messenger molecule. Biochemical and physiologic studies were analyzed if the same results were found by three or more independent observers. Two major classes of nitric oxide synthase enzymes produce nitric oxide. The constitutive isoforms found in endothelial cells and neurons release small amounts of nitric oxide for brief periods to signal adjacent cells, whereas the inducible isoform found in macrophages releases large amounts of nitric oxide continuously to eliminate bacteria and parasites. By diffusing into adjacent cells and binding to enzymes that contain iron, nitric oxide plays many important physiologic roles. It regulates blood pressure, transmits signals between neurons, and suppresses pathogens. Excess amounts, however, can damage host cells, causing neurotoxicity during strokes and causing the hypotension associated with sepsis. Nitric oxide is a simple molecule with many physiologic roles in the cardiovascular, neurologic, and immune systems. Although the general principles of nitric oxide synthesis are known, further research is necessary to determine what role it plays in causing disease.

  5. It has been suggested that oxidative stress, especially oxidative ...

    African Journals Online (AJOL)

    nabipour

    2012-02-14

    Feb 14, 2012 ... 1Department of Clinical Biochemistry, Faculty of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran. 2Department of Cardiology ... oxidative modification of low-density lipoproteins (LDL), may play a causative role in ... the oxidation of lipids in the cell membrane especially the oxidation of LDL.

  6. Oxidative Stress in BPH.

    Science.gov (United States)

    Savas, M; Verit, A; Ciftci, H; Yeni, E; Aktan, E; Topal, U; Erel, O

    2009-01-01

    In the present study, we investigated the relationship between potency of oxidative stress and BPH and this may assist to contribute to the realistic explanation of the ethiopathogenesis of BPH. Seventy four newly diagnosed men with BPH (mean age: 54+/-11.2), who had not undergone any previous treatment for BPH, and 62 healthy volunteers (mean age: 55+/-14) were enrolled in the present study. To determine the antioxidative status of plasma, total antioxidant capacity (TAC) was calculated, and to determine the oxidative status of plasma (TOS) total peroxide levels were measured. The ratio of TAC to total peroxide was accepted as an indicator of oxidative stress (OSI). Data are presented as mean SD +/- unless specified. Student t-test and correlation analyses were used to evaluate the statistical significance differences in the median values recorded for all parameters between BPH and control group. Plasma TAC TOS were found in patients and controls (1.70 +/- 0.32, 1.68 +/- 0.19 micromol Trolox Equiv./L), (12.48 +/- 1.98, 12.40 +/- 1.14 micromol / L) respectively. OSI was calculated as 7.57 +/- 1.91, 7.48 +/- 1.33, respectively. Plasma TAC, TOS and OSI levels were not found to be significantly difference between patients and control subjects (p>0.05, p>0.05, p>0.05). The present study has shown that there were not relationship between potency of oxidative stress and BPH. Further well designed studies should be planned to find out whether the oxidative stress-related parameters play role in BPH as an interesting pathology in regard of the etiopathogenesis.

  7. Optimization of APS-ZrO{sub 2}-thermal barrier coatings by variations of creep strength and interface roughness; Optimierung von APS-ZrO{sub 2}-Waermedaemmschichten durch Variationen der Kriechfestigkeit und der Grenzflaechenrauhigkeit

    Energy Technology Data Exchange (ETDEWEB)

    Schweda, Mario

    2011-07-01

    Gas turbines operate at combustion chamber temperatures up to 1400 C. Therefore the blades and the combustion chamber lining, which consist of Ni-superalloys for highest loads, are coated with a thermal barrier coating (TBC) of zirconium oxide and an underlying oxidation protection coating of MCrAlY-alloys (M=Ni, Co). At high temperature the MCrAlY-coating oxidizes and an Al{sub 2}O{sub 3}-scale (thermally grown oxide, TGO) forms between MCrAlY-coating and TBC, what constrains the oxidation of the base material. At plasma sprayed TBCs, the MCrAlY-coating provides a bond coat (BC) for the TBC at the same time and therefore is roughened by sandblasting before the deposition of the TBC. By the growth of the Al{sub 2}O{sub 3}-scale and the start up and run down of the gas turbine, stresses arise in the TBC, which lead to lateral crack formation in the field of the TBC-BC-interface and finally to the spallation of the TBC. Thereby other parts of the turbine can be damaged, what causes high costs. Therefrom the aim is to delay the crack growth as strong as possible or rather to maximize the lifetime of the TBC. For this purpose the material properties of the coating components have to be optimized. In the present work, the influence of creep strength of BC and TGO and the influence of TBC-BC-interface-roughness on the lifetime and damage evolution of plasma sprayed ZrO{sub 2}-TBCs are investigated. To determine the lifetime, cylindrical specimens with plasma sprayed ZrO{sub 2}-TBC were produced and thermally cycled with a minimum and maximum temperature of 60 C and 1050 C and a dwell time at maximal temperature of 2h. To exclude the interdiffusion and thermal mismatch between BC and Ni-superalloy, a model system was used: The Ni-superalloy was left and the substrate material consists completely of a BC-like FeCrAlY-alloy. The model system was simulated by the project partner TU Braunschweig with the FE-method. The TBC-BC-interface-roughness was abstracted by a 2

  8. Staged membrane oxidation reactor system

    Science.gov (United States)

    Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

    2012-09-11

    Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

  9. Electrochemical analysis of metal oxides

    Czech Academy of Sciences Publication Activity Database

    Grygar, Tomáš; Bezdička, Petr; Hradil, David; Pikna, L.

    90-91, - (2003), s. 45-50 ISSN 1012-0394 Institutional research plan: CEZ:AV0Z4032918 Keywords : powder electroanalysis * Fe oxides * Mn oxides Subject RIV: CA - Inorganic Chemistry Impact factor: 0.687, year: 2003

  10. Thin film metal-oxides

    CERN Document Server

    Ramanathan, Shriram

    2009-01-01

    Presents an account of the fundamental structure-property relations in oxide thin films. This title discusses the functional properties of thin film oxides in the context of applications in the electronics and renewable energy technologies.

  11. Risks and opportunities of the liberalized electricity market. Partial project: BoFiT, an integrated decision support system for retaining the competitiveness of the cogeneration technology. Final report; Risiken und Chancen des liberalisierten Strommarktes. Teilprojekt: Integrierte Entscheidungsunterstuetzung durch BoFiT zur Erhaltung der Wettbewerbsfaehigkeit der Kraft-Waerme-Kopplung. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Stock, G.; Scheidt, M.

    2002-06-04

    The energy management system called BoFiT and specific new applications are explained which have been developed as one project task of the coordinated research project sponsored by the German ministry of economics,(BMWi), entitled ''Risks and opportunities of the liberalized electricity market''. The major objective of the project is: Finding efficient strategies to ensure the competitiveness of the cogeneration technology in the deregulated power and gas markets, in particular for the purpose of enhancing the penetration of the ecologically beneficial, cogenerated district heating supply in those markets. The focus of this report is on a specific application of the integrated BoFiT decision support system, for which the ''model for microsimulation of spot transactions at the Power Exchange based on a multi-agent system'' has been developed and is explained in great detail. (orig./CB) [German] Mit dem Energiemanagementsystem BoFiT soll den Unternehmen eine effektive und operativ nutzbare Entscheidungsunterstuetzung angeboten werden. Wesentliche Ziele des Verbundprojektes des BMWi sind: Unterstuetzung der KWK und speziell der darauf basierenden oekologisch sinnvollen Fernwaermeversorgung durch Anpassung von Arbeitsablaeufen und Werkzeugen zur Findung betriebswirtschaftlich optimaler Einsatz- und Betriebsstrategien; Kostenoptimierung der Kraftwerke, Vertraege und Stromhandelsaktivitaeten unter den Randbedingungen der deregulierten Strom- und Gasmaerkte. Als Beispiel einer solchen integrierten Entscheidungsunterstuetzung wird das ''Modell zur Mikrosimulation des Spothandels von Strom auf der Basis eines Multi-Agenten-Systems'' ausfuehrlich beschrieben. (orig./CB)

  12. Review Of Plutonium Oxidation Literature

    International Nuclear Information System (INIS)

    Korinko, P.

    2009-01-01

    A brief review of plutonium oxidation literature was conducted. The purpose of the review was to ascertain the effect of oxidation conditions on oxide morphology to support the design and operation of the PDCF direct metal oxidation (DMO) furnace. The interest in the review was due to a new furnace design that resulted in oxide characteristics that are different than those of the original furnace. Very little of the published literature is directly relevant to the DMO furnace operation, which makes assimilation of the literature data with operating conditions and data a convoluted task. The oxidation behavior can be distilled into three regimes, a low temperature regime (RT to 350 C) with a relatively slow oxidation rate that is influenced by moisture, a moderate temperature regime (350-450 C) that is temperature dependent and relies on more or less conventional oxidation growth of a partially protective oxide scale, and high temperature oxidation (> 500 C) where the metal autocatalytically combusts and oxidizes. The particle sizes obtained from these three regimes vary with the finest being from the lowest temperature. It is surmised that the slow growth rate permits significant stress levels to be achieved that help break up the oxides. The intermediate temperatures result in a fairly compact scale that is partially protective and that grows to critical thickness prior to fracturing. The growth rate in this regime may be parabolic or paralinear, depending on the oxidation time and consequently the oxide thickness. The high temperature oxidation is invariant in quiescent or nearly quiescent conditions due to gas blanketing while it accelerates with temperature under flowing conditions. The oxide morphology will generally consist of fine particles ( 250 (micro)m). The particle size ratio is expected to be < 5%, 25%, and 70% for fine, medium and large particles, respectively, for metal temperatures in the 500-600 C range.

  13. Oxidative Decarboxylation of Levulinic Acid by Cupric Oxides

    Directory of Open Access Journals (Sweden)

    Lu Lin

    2010-11-01

    Full Text Available In this paper, cupric oxides was found to effectively oxidize levulinic acid (LA and lead to the decarboxylation of levulinic acid to 2-butanone. The effects of cupric oxide dosage, reaction time and initial pH value were investigated in batch experiments and a plausible mechanism was proposed. The results showed that LA decarboxylation over cupric oxides at around 300 °C under acidic conditions produced the highest yield of butanone (67.5%. In order to elucidate the catalytic activity of cupric oxides, XRD, AFM, XPS and H2-TPR techniques was applied to examine their molecular surfaces and their effects on the reaction process.

  14. Self-assembled manganese oxide structures through direct oxidation

    KAUST Repository

    Zhao, Chao; Wang, Qingxiao; Yang, Yang; Zhang, Bei; Zhang, Xixiang

    2012-01-01

    The morphology and phase of self-assembled manganese oxides during different stages of thermal oxidation were studied. Very interesting morphological patterns of Mn oxide films were observed. At the initial oxidation stage, the surface was characterized by the formation of ring-shaped patterns. As the oxidation proceeded to the intermediate stage, concentric plates formed to relax the compressive stress. Our experimental results gave a clear picture of the evolution of the structures. We also examined the properties of the structures. © 2012 Elsevier B.V.

  15. Self-assembled manganese oxide structures through direct oxidation

    KAUST Repository

    Zhao, Chao

    2012-12-01

    The morphology and phase of self-assembled manganese oxides during different stages of thermal oxidation were studied. Very interesting morphological patterns of Mn oxide films were observed. At the initial oxidation stage, the surface was characterized by the formation of ring-shaped patterns. As the oxidation proceeded to the intermediate stage, concentric plates formed to relax the compressive stress. Our experimental results gave a clear picture of the evolution of the structures. We also examined the properties of the structures. © 2012 Elsevier B.V.

  16. The aqueous chemistry of oxides

    CERN Document Server

    Bunker, Bruce C

    2016-01-01

    The Aqueous Chemistry of Oxides is a comprehensive reference volume and special topics textbook that explores all of the major chemical reactions that take place between oxides and aqueous solutions. The book highlights the enormous impact that oxide-water reactions have in advanced technologies, materials science, geochemistry, and environmental science.

  17. Zinc oxide for spintronic applications. Sol-gel processes and characterization; Zinkoxid fuer spintronische Anwendungen. Sol-Gel-Prozesse und Charakterisierung

    Energy Technology Data Exchange (ETDEWEB)

    Knies, Christoph

    2009-06-15

    Since the year 1999 published theoretical models predict for systems on the base of cobalt-doped zinc oxide the formation of a ferromagnetic order with Curie temperatures above room temperature. Essential condition for the occurrence of the ferromagnetic interaction is the presence of additional charge carriers, which interact with the states of the cobalt. The aim of this thesis represents the fabrication of cobalt-doped thin layers by means of the dip-coating procedure, the characterization of the properties of the matter, as well as the study of the effects arising by additional doping with flat dopants on the magnetic properties and the charge-carrier transport. The structural characterization by means of X-ray diffractometry hints on a one-phase nanocrystalline growth of the ZnO in wurtzite structure at a mean particle size between 20 and 30 nm. Cobalt-based heterophases can be observed for doping concentrations above 20%. Optical and magnetic-resonance studies let no doubt on the insertion of the Co in the 2+ charge state in the lattice place of the zinc in 3d{sup 7} configuration. In measurements of the optical absorption and the magnetic circular dichroism (MCD) the internal crystal-field transitions of the Co{sup 2+} in the visible and additionally in the near-infrared range are to be observed. Abroad absorption transition observed above 2.8 eV was assigned to a Co{sup 2+/+} charge-carrier transition. Both MCD and ESR measurements let to be concluded on a purely paramagnetic behaviour of the matter. By annealing of the samples in zinc vapor an interstitial insection of the zinc could be reached. The formation of a corresponding flat donor state can be controlled by observation of the absorption by free charge carriers in the near-infrared range. By this the essential conditions of the theoretical model named above can be considered as fulfilled. Actually in SQUID magnetization measurements characteristic hysteresis curves up to 300 K can be observed. The

  18. Interactions between iron oxides and copper oxides under hydrothermal conditions

    Energy Technology Data Exchange (ETDEWEB)

    McGarvey, G B; Owen, D G

    1995-08-01

    Under hydrothermal conditions, magnetite and hematite have been shown to undergo interconversion reactions, the extent of which is controlled in part by the presence of copper oxides. In oxygenated water, the degree to which magnetite was oxidized to hematite was found to be dependent on the presence of CuO or Cu{sub 2}O. When these materials were absent, the oxidation of magnetite was limited by the dissolved oxygen in the aqueous system. Participation of the copper oxides in the oxidation process was confirmed by more complete conversion of magnetite was also influenced by the presence of the copper oxides. In addition to driving the reduction to completion, the presence of the copper oxides also exerted a strong influence over the morphology of the magnetite that formed. (author). 13 refs., 1 tab., 3 figs.

  19. Iron oxide surfaces

    Science.gov (United States)

    Parkinson, Gareth S.

    2016-03-01

    The current status of knowledge regarding the surfaces of the iron oxides, magnetite (Fe3O4), maghemite (γ-Fe2O3), haematite (α-Fe2O3), and wüstite (Fe1-xO) is reviewed. The paper starts with a summary of applications where iron oxide surfaces play a major role, including corrosion, catalysis, spintronics, magnetic nanoparticles (MNPs), biomedicine, photoelectrochemical water splitting and groundwater remediation. The bulk structure and properties are then briefly presented; each compound is based on a close-packed anion lattice, with a different distribution and oxidation state of the Fe cations in interstitial sites. The bulk defect chemistry is dominated by cation vacancies and interstitials (not oxygen vacancies) and this provides the context to understand iron oxide surfaces, which represent the front line in reduction and oxidation processes. Fe diffuses in and out from the bulk in response to the O2 chemical potential, forming sometimes complex intermediate phases at the surface. For example, α-Fe2O3 adopts Fe3O4-like surfaces in reducing conditions, and Fe3O4 adopts Fe1-xO-like structures in further reducing conditions still. It is argued that known bulk defect structures are an excellent starting point in building models for iron oxide surfaces. The atomic-scale structure of the low-index surfaces of iron oxides is the major focus of this review. Fe3O4 is the most studied iron oxide in surface science, primarily because its stability range corresponds nicely to the ultra-high vacuum environment. It is also an electrical conductor, which makes it straightforward to study with the most commonly used surface science methods such as photoemission spectroscopies (XPS, UPS) and scanning tunneling microscopy (STM). The impact of the surfaces on the measurement of bulk properties such as magnetism, the Verwey transition and the (predicted) half-metallicity is discussed. The best understood iron oxide surface at present is probably Fe3O4(100); the structure is

  20. Manganese Oxidation by Bacteria: Biogeochemical Aspects

    Digital Repository Service at National Institute of Oceanography (India)

    Sujith, P.P.; LokaBharathi, P.A.

    Manganese is an essential trace metal that is not as readily oxidizable like iron. Several bacterial groups posses the ability to oxidize Mn effectively competing with chemical oxidation. The oxides of Mn are the strongest of the oxidants, next...

  1. Thin Solid Oxide Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material, at least one metal and a catalyst...... material, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same. The present invention also relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous...... cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material and a catalyst material, wherein the electrolyte material is doper zirconia, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same...

  2. Defects at oxide surfaces

    CERN Document Server

    Thornton, Geoff

    2015-01-01

    This book presents the basics and characterization of defects at oxide surfaces. It provides a state-of-the-art review of the field, containing information to the various types of surface defects, describes analytical methods to study defects, their chemical activity and the catalytic reactivity of oxides. Numerical simulations of defective structures complete the picture developed. Defects on planar surfaces form the focus of much of the book, although the investigation of powder samples also form an important part. The experimental study of planar surfaces opens the possibility of applying the large armoury of techniques that have been developed over the last half-century to study surfaces in ultra-high vacuum. This enables the acquisition of atomic level data under well-controlled conditions, providing a stringent test of theoretical methods. The latter can then be more reliably applied to systems such as nanoparticles for which accurate methods of characterization of structure and electronic properties ha...

  3. Electrorheology of graphene oxide.

    Science.gov (United States)

    Zhang, Wen Ling; Liu, Ying Dan; Choi, Hyoung Jin; Kim, Sang Guk

    2012-04-01

    Novel polarizable graphene oxide (GO) particles with oxidized groups on their edge and basal planes were prepared by a modified Hummers method, and their electro-responsive electrorheological (ER) characteristics when dispersed in silicone oil were examined with and without an electric field applied. The fibrillation phenomenon of this GO-based electro-responsive fluid was also observed via an optical microscope under an applied electric field. Both flow curves and dielectric spectra of the ER fluid were measured using a rotational rheometer and a LCR meter, respectively. Its viscoelastic properties of both storage and loss moduli were also examined using a vertical oscillation rheometer equipped with a high voltage generator, finding that the GO-based smart ER system behaves as a viscoelastic material under an applied electric field.

  4. Mechanochemistry of titanium oxides

    Directory of Open Access Journals (Sweden)

    Veljković Ivana

    2009-01-01

    Full Text Available Mechanochemistry represents an alternative route in synthesis of nanomaterials. Mechanochemical routes are attractive because of their simplicity, flexibility, and ability to prepare materials by solid state reactions at room temperature. The aim of this work is the mechanochemical synthesis of nanostructured titanium oxides of different composition starting from mixtures of Ti and TiO2, TiO and TiO2 or Ti2O3 and TiO2. Emphasis is on the Magneli phases Ti4O7 and Ti5O9 because their mixture is commercially known as EBONEX material. The materials prepared were characterized by XRPD, TG/DTA analysis, SEM and optical microscopy. Titanium monoxide and several Magneli oxides, Ti4O7, Ti5O9 and Ti6O11, are successfully prepared. The results are very interesting because the EBONEX materials were prepared at lower than usual temperature, which would decrease the effective cost of production.

  5. Oxidative metabolism in muscle.

    OpenAIRE

    Ferrari, M; Binzoni, T; Quaresima, V

    1997-01-01

    Oxidative metabolism is the dominant source of energy for skeletal muscle. Near-infrared spectroscopy allows the non-invasive measurement of local oxygenation, blood flow and oxygen consumption. Although several muscle studies have been made using various near-infrared optical techniques, it is still difficult to interpret the local muscle metabolism properly. The main findings of near-infrared spectroscopy muscle studies in human physiology and clinical medicine are summarized. The advantage...

  6. Chemical oxidizers treat wastewater

    International Nuclear Information System (INIS)

    Stephenson, F.A.

    1992-01-01

    Based on the inherent benefits of these original oxidation systems, a second generation of advanced oxidation processes (AOPs) has emerged. These processes combine key features of the first generation technologies with more sophisticated advances in UV technology, such as the new pulsed plasma xenon flash lamp that emits high-energy, high-intensity UV light. Second generation systems can be equipped with a transmittance controller to prevent lamp fouling or scaling. The coupling of the first generation's technology with the new UV sources provides the rapid destruction of chlorinated and nonchlorinated hydrocarbons and humic acids from contaminated water. It also is effective in the treatment of organic laden gases from soil vapor extraction systems. AOPs may promote the oxidation (and subsequent removal) of heavy metals in water, though few data are available to verify the claim. The success of AOPs, including ozonation with UV light, hydrogen peroxide with UV light and advanced photolysis, is linked with their creation of hydroxyl-free radicals (OH·) that are effective in eliminating contaminants such as formaldehyde, chlorinated hydrocarbons and chlorinated solvents. Hydroxyl free-radicals are consumed in microsecond reactions and exhibit little substrate selectivity with the exception of halogenated alkanes such as chloroform. They can act as chain carriers. Given their power, hydroxyl free-radicals react with virtually all organic solutes more quickly (especially in water) than any other oxidants, except fluorine. There are projects that have found the combination of some AOPs to be the most efficient organic destruction techniques for the job. For example, one project successfully remediated groundwater contaminated with gasoline and Number 2 diesel through successive treatments of ozone and hydrogen peroxide with ultraviolet light, followed by granular activated carbon. 5 refs., 2 tabs

  7. Krypton oxides under pressure

    OpenAIRE

    Zaleski-Ejgierd, Patryk; Łata, Paweł

    2015-01-01

    Under high pressure, krypton, one of the most inert elements is predicted to become sufficiently reactive to form a new class of krypton compounds; krypton oxides. Using modern ab-initio evolutionary algorithms in combination with Density Functional Theory, we predict the existence of several thermodynamically stable Kr/O species at elevated pressures. In particular, our calculations indicate that at approx. 300?GPa the monoxide, KrO, should form spontaneously and remain thermo- and dynamical...

  8. Radiolytic graphite oxidation revisited

    International Nuclear Information System (INIS)

    Minshall, P.C.; Sadler, I.A.; Wickham, A.J.

    1996-01-01

    The importance of radiolytic oxidation in graphite-moderated CO 2 -cooled reactors has long been recognised, especially in the Advanced Gas-Cooled Reactors where potential rates are higher because of the higher gas pressure and ratings than the earlier Magnox designs. In all such reactors, the rate of oxidation is partly inhibited by the CO produced in the reaction and, in the AGR, further reduced by the deliberate addition of CH 4 . Significant roles are also played by H 2 and H 2 O. This paper reviews briefly the mechanisms of these processes and the data on which they are based. However, operational experience has demonstrated that these basic principles are unsatisfactory in a number of respects. Gilsocarbon graphites produced by different manufacturers have demonstrated a significant difference in oxidation rate despite a similar specification and apparent equivalence in their pore size and distribution, considered to be the dominant influence on oxidation rate for a given coolant-gas composition. Separately, the inhibiting influence of CH 4 , which for many years had been considered to arise from the formation of a sacrificial deposit on the pore walls, cannot adequately be explained by the actual quantities of such deposits found in monitoring samples which frequently contain far less deposited carbon than do samples from Magnox reactors where the only source of such deposits is the CO. The paper also describes the current status of moderator weight-loss predictions for Magnox and AGR Moderators and the validation of the POGO and DIFFUSE6 codes respectively. 2 refs, 5 figs

  9. Oxidative stability of polyaniline

    Czech Academy of Sciences Publication Activity Database

    Stejskal, Jaroslav; Exnerová, Milena; Morávková, Zuzana; Trchová, Miroslava; Hromádková, Jiřina; Prokeš, J.

    2012-01-01

    Roč. 97, č. 6 (2012), s. 1026-1033 ISSN 0141-3910 R&D Projects: GA ČR GA202/09/1626; GA ČR GAP205/12/0911 Institutional research plan: CEZ:AV0Z40500505 Institutional support: RVO:61389013 Keywords : polyaniline * nanotubes * oxidation stability Subject RIV: BK - Fluid Dynamics Impact factor: 2.770, year: 2012

  10. Molecular theory of graphene oxide.

    Science.gov (United States)

    Sheka, Elena F; Popova, Nadezhda A

    2013-08-28

    Applied to graphene oxide, the molecular theory of graphene considers its oxide as a final product in the succession of polyderivatives related to a series of oxidation reactions involving different oxidants. The graphene oxide structure is created in the course of a stepwise computational synthesis of polyoxides of the (5,5) nanographene molecule governed by an algorithm that takes into account the molecule's natural radicalization due to the correlation of its odd electrons, the extremely strong influence of the structure on properties, and a sharp response of the molecule behavior on small actions of external factors. Taking these together, the theory has allowed for a clear, transparent and understandable explanation of the hot points of graphene oxide chemistry and suggesting reliable models of both chemically produced and chemically reduced graphene oxides.

  11. The competing oxide and sub-oxide formation in metal-oxide molecular beam epitaxy

    International Nuclear Information System (INIS)

    Vogt, Patrick; Bierwagen, Oliver

    2015-01-01

    The hetero-epitaxial growth of the n-type semiconducting oxides β-Ga 2 O 3 , In 2 O 3 , and SnO 2 on c- and r-plane sapphire was performed by plasma-assisted molecular beam epitaxy. The growth-rate and desorbing flux from the substrate were measured in-situ under various oxygen to metal ratios by laser reflectometry and quadrupole mass spectrometry, respectively. These measurements clarified the role of volatile sub-oxide formation (Ga 2 O, In 2 O, and SnO) during growth, the sub-oxide stoichiometry, and the efficiency of oxide formation for the three oxides. As a result, the formation of the sub-oxides decreased the growth-rate under metal-rich growth conditions and resulted in etching of the oxide film by supplying only metal flux. The flux ratio for the exclusive formation of the sub-oxide (e.g., the p-type semiconductor SnO) was determined, and the efficiency of oxide formation was found to be the highest for SnO 2 , somewhat lower for In 2 O 3 , and the lowest for Ga 2 O 3 . Our findings can be generalized to further oxides that possess related sub-oxides

  12. The oxidative hypothesis of senescence

    Directory of Open Access Journals (Sweden)

    Gilca M

    2007-01-01

    Full Text Available The oxidative hypothesis of senescence, since its origin in 1956, has garnered significant evidence and growing support among scientists for the notion that free radicals play an important role in ageing, either as "damaging" molecules or as signaling molecules. Age-increasing oxidative injuries induced by free radicals, higher susceptibility to oxidative stress in short-lived organisms, genetic manipulations that alter both oxidative resistance and longevity and the anti-ageing effect of caloric restriction and intermittent fasting are a few examples of accepted scientific facts that support the oxidative theory of senescence. Though not completely understood due to the complex "network" of redox regulatory systems, the implication of oxidative stress in the ageing process is now well documented. Moreover, it is compatible with other current ageing theories (e.g., those implicating the mitochondrial damage/mitochondrial-lysosomal axis, stress-induced premature senescence, biological "garbage" accumulation, etc. This review is intended to summarize and critically discuss the redox mechanisms involved during the ageing process: sources of oxidant agents in ageing (mitochondrial -electron transport chain, nitric oxide synthase reaction- and non-mitochondrial- Fenton reaction, microsomal cytochrome P450 enzymes, peroxisomal β -oxidation and respiratory burst of phagocytic cells, antioxidant changes in ageing (enzymatic- superoxide dismutase, glutathione-reductase, glutathion peroxidase, catalase- and non-enzymatic glutathione, ascorbate, urate, bilirubine, melatonin, tocopherols, carotenoids, ubiquinol, alteration of oxidative damage repairing mechanisms and the role of free radicals as signaling molecules in ageing.

  13. Oxidation kinetics of (B6O) boron oxide

    International Nuclear Information System (INIS)

    Makarov, V.S.; Solov'ev, N.E.; Ugaj, Ya.A.

    1987-01-01

    Reactivity of B 6 O to oxygen is investigated. It is shown that the process of B 6 O oxidation in the air in the temperature range 760-1150 K results in the maximum transformation degree equal to 0.35. At the initial stages oxidation proceeds in kinetic regime, at final stages - in diffusion one, and high viscosity of B 2 O 3 probably affects the oxidation process

  14. Partial oxidation process

    International Nuclear Information System (INIS)

    Najjar, M.S.

    1987-01-01

    A process is described for the production of gaseous mixtures comprising H/sub 2/+CO by the partial oxidation of a fuel feedstock comprising a heavy liquid hydrocarbonaceous fuel having a nickel, iron, and vanadium-containing ash or petroleum coke having a nickel, iron, and vanadium-containing ash, or mixtures thereof. The feedstock includes a minimum of 0.5 wt. % of sulfur and the ash includes a minimum of 5.0 wt. % vanadium, a minimum of 0.5 ppm nickel, and a minimum of 0.5 ppm iron. The process comprises: (1) mixing together a copper-containing additive with the fuel feedstock; wherein the weight ratio of copper-containing additive to ash in the fuel feedstock is in the range of about 1.0-10.0, and there is at least 10 parts by weight of copper for each part by weight of vanadium; (2) reacting the mixture from (1) at a temperature in the range of 2200 0 F to 2900 0 F and a pressure in the range of about 5 to 250 atmospheres in a free-flow refactory lined partial oxidation reaction zone with a free-oxygen containing gas in the presence of a temperature moderator and in a reducing atmosphere to produce a hot raw effluent gas stream comprising H/sub 2/+CO and entrained molten slag; and where in the reaction zone and the copper-containing additive combines with at least a portion of the nickel and iron constituents and sulfur found in the feedstock to produce a liquid phase washing agent that collects and transports at least a portion of the vanadium-containing oxide laths and spinels and other ash components and refractory out of the reaction zone; and (3) separating nongaseous materials from the hot raw effluent gas stream

  15. The 2016 oxide electronic materials and oxide interfaces roadmap

    DEFF Research Database (Denmark)

    Lorenz, M.; Rao, M. S. Ramachandra; Venkatesan, T.

    2016-01-01

    of these materials to understand the tunability of their properties and the novel properties that evolve due to their nanostructured nature is another facet of the challenge. The research related to the oxide electronic field is at an impressionable stage, and this has motivated us to contribute with a roadmap......, Pentcheva, and Gegenwart. Finally, Miletto Granozio presents the European action ‘towards oxide-based electronics’ which develops an oxide electronics roadmap with emphasis on future nonvolatile memories and the required technologies.In summary, we do hope that this oxide roadmap appears as an interesting...

  16. Solid oxide fuel cells fueled with reducible oxides

    Science.gov (United States)

    Chuang, Steven S.; Fan, Liang Shih

    2018-01-09

    A direct-electrochemical-oxidation fuel cell for generating electrical energy includes a cathode provided with an electrochemical-reduction catalyst that promotes formation of oxygen ions from an oxygen-containing source at the cathode, a solid-state reduced metal, a solid-state anode provided with an electrochemical-oxidation catalyst that promotes direct electrochemical oxidation of the solid-state reduced metal in the presence of the oxygen ions to produce electrical energy, and an electrolyte disposed to transmit the oxygen ions from the cathode to the solid-state anode. A method of operating a solid oxide fuel cell includes providing a direct-electrochemical-oxidation fuel cell comprising a solid-state reduced metal, oxidizing the solid-state reduced metal in the presence of oxygen ions through direct-electrochemical-oxidation to obtain a solid-state reducible metal oxide, and reducing the solid-state reducible metal oxide to obtain the solid-state reduced metal.

  17. Sputtered tin oxide and titanium oxide thin films as alternative transparent conductive oxides

    Energy Technology Data Exchange (ETDEWEB)

    Boltz, Janika

    2011-12-12

    Alternative transparent conductive oxides to tin doped indium oxide have been investigated. In this work, antimony doped tin oxide and niobium doped titanium oxide have been studied with the aim to prepare transparent and conductive films. Antimony doped tin oxide and niobium doped titanium oxide belong to different groups of oxides; tin oxide is a soft oxide, while titanium oxide is a hard oxide. Both oxides are isolating materials, in case the stoichiometry is SnO{sub 2} and TiO{sub 2}. In order to achieve transparent and conductive films free carriers have to be generated by oxygen vacancies, by metal ions at interstitial positions in the crystal lattice or by cation doping with Sb or Nb, respectively. Antimony doped tin oxide and niobium doped titanium oxide films have been prepared by reactive direct current magnetron sputtering (dc MS) from metallic targets. The process parameters and the doping concentration in the films have been varied. The films have been electrically, optically and structurally analysed in order to analyse the influence of the process parameters and the doping concentration on the film properties. Post-deposition treatments of the films have been performed in order to improve the film properties. For the deposition of transparent and conductive tin oxide, the dominant parameter during the deposition is the oxygen content in the sputtering gas. The Sb incorporation as doping atoms has a minor influence on the electrical, optical and structural properties. Within a narrow oxygen content in the sputtering gas highly transparent and conductive tin oxide films have been prepared. In this study, the lowest resistivity in the as deposited state is 2.9 m{omega} cm for undoped tin oxide without any postdeposition treatment. The minimum resistivity is related to a transition to crystalline films with the stoichiometry of SnO{sub 2}. At higher oxygen content the films turn out to have a higher resistivity due to an oxygen excess. After post

  18. Actinide oxide photodiode and nuclear battery

    Energy Technology Data Exchange (ETDEWEB)

    Sykora, Milan; Usov, Igor

    2017-12-05

    Photodiodes and nuclear batteries may utilize actinide oxides, such a uranium oxide. An actinide oxide photodiode may include a first actinide oxide layer and a second actinide oxide layer deposited on the first actinide oxide layer. The first actinide oxide layer may be n-doped or p-doped. The second actinide oxide layer may be p-doped when the first actinide oxide layer is n-doped, and the second actinide oxide layer may be n-doped when the first actinide oxide layer is p-doped. The first actinide oxide layer and the second actinide oxide layer may form a p/n junction therebetween. Photodiodes including actinide oxides are better light absorbers, can be used in thinner films, and are more thermally stable than silicon, germanium, and gallium arsenide.

  19. Trends in reactivity of oxides

    DEFF Research Database (Denmark)

    Toftelund, Anja

    The results in this thesis are based on Density Functional Theory calculations. The catalytic activity of oxides and other compound materials are investigated. It is found that the adsorption energy of the molecules NH2, NH, OH and SH on transition metal nitride, oxide and sulfide surfaces scales......, and I) and OH on a wide range of rutile oxide surfaces. Furthermore, Brønsted-Evans-Polanyi (BEP) relations are found for the adsorption of a large number of molecules (including Cl, Br and I) on transition metal oxides. In these relations the activation energies scale linearly with the dissociative...... chemisorption energies. It turns out that the BEP relation for rutile oxides is almost coinciding with the dissociation line, i.e. no barrier exists for the reactive surfaces. The heterogeneous catalytic oxidation of hydrogen halides (HCl, HBr, and HI) is investigated. A micro-kinetic model is solved...

  20. Quantification of the magnetization-transfer contrast effect: can it yield additional information in differentiation of musculoskeletal lesions particularly in separation of benign from malignant lesions; Quantifizierung des Magnetization Transfer Contrast (MTC) Effektes durch Berechnung von MT-Quotienten: Ergeben sich Zusatzinformationen fuer die Differenzierung benigner und maligner Erkrankungen des Bewegungsapparates?

    Energy Technology Data Exchange (ETDEWEB)

    Vahlensieck, M.; Traeber, F.; Schild, H. [Radiologische Universitaetsklinik Bonn (Germany); Gieseke, J. [Philips Medizinsysteme (Germany)

    1999-12-01

    Purpose: To investigate the potential information of the amount of magnetization-transfer effect in musculoskeletal lesions and to compare MT ratios from benign and malignant musculoskeletal lesions. Material and Method: 49 patients with malignant tumors (3 osteosarcoma, 3 malignant fibrous histiocytoma, 4 chondrosarcoma, 2 Ewing sarcomas) and benign lesions (8 chondroma, 2 fibrous dysplasia, 3 osteoid-osteoma, 6 ganglion cyst, 3 cyst, 3 osteomyelitis, 4 tendinitis, 3 rotator cuff tear, 5 scar tissue) were scanned using routine MRI protocols including T{sub 1}- and T{sub 2}-weighted spin echo as well as T{sub 2}*-weighted gradient echo (FFE) sequences at 1.5 Tesla (ACS II, Philips Medical). Additionally MTC images were generated by combining the FFE sequence and the off-resonance MT technique (-1500 Hz off-resonance frequency, 1770 flip angle and 50 ms pulse duration). MT ratios were calculated as SI{sub o}-SI{sub m}/SI{sub o}. Results: The MT ratio of benign lesions was 26{+-}15%, that of malignant lesions was 22{+-}6%. The difference was statistically not significant. As expected muscle showed a high MT ratio of 50{+-}8%. Scar tissue demonstrated an MT ratio of 39{+-}16% which was significantly higher than the tumor MT ratios. Conclusion: MTC (MT ratios) failed to show significant differences between benign and malignant lesions as was expected due to basic differences in cellularity, rate of mitosis and chromatin content. MTC might however gain more importance in separating scar tissue from recurrent tumor in the future. (orig.) [German] Zielsetzung: Durch die Quantifizierung des Magnetization Transfer Contrastes sollte untersucht werden, ob sich Zusatzinformationen in der Magnetresonanztomographie des Stuetz- und Bewegungsapparates ergeben. Insbesondere sollte ermittelt werden, ob gut- und boesartige Laesionen unterschiedliche MT-Quotienten aufweisen. Material und Methode: 49 Patienten mit boesartigen Tumoren (3 Osteosarkom, 4 Chondrosarkom, 3 Malignes

  1. Rare Earth Oxide Thin Films

    CERN Document Server

    Fanciulli, Marco

    2007-01-01

    Thin rare earth (RE) oxide films are emerging materials for microelectronic, nanoelectronic, and spintronic applications. The state-of-the-art of thin film deposition techniques as well as the structural, physical, chemical, and electrical properties of thin RE oxide films and of their interface with semiconducting substrates are discussed. The aim is to identify proper methodologies for the development of RE oxides thin films and to evaluate their effectiveness as innovative materials in different applications.

  2. Transparent conducting oxide nanotubes

    Science.gov (United States)

    Alivov, Yahya; Singh, Vivek; Ding, Yuchen; Nagpal, Prashant

    2014-09-01

    Thin film or porous membranes made of hollow, transparent, conducting oxide (TCO) nanotubes, with high chemical stability, functionalized surfaces and large surface areas, can provide an excellent platform for a wide variety of nanostructured photovoltaic, photodetector, photoelectrochemical and photocatalytic devices. While large-bandgap oxide semiconductors offer transparency for incident light (below their nominal bandgap), their low carrier concentration and poor conductivity makes them unsuitable for charge conduction. Moreover, materials with high conductivity have nominally low bandgaps and hence poor light transmittance. Here, we demonstrate thin films and membranes made from TiO2 nanotubes heavily-doped with shallow Niobium (Nb) donors (up to 10%, without phase segregation), using a modified electrochemical anodization process, to fabricate transparent conducting hollow nanotubes. Temperature dependent current-voltage characteristics revealed that TiO2 TCO nanotubes, doped with 10% Nb, show metal-like behavior with resistivity decreasing from 6.5 × 10-4 Ωcm at T = 300 K (compared to 6.5 × 10-1 Ωcm for nominally undoped nanotubes) to 2.2 × 10-4 Ωcm at T = 20 K. Optical properties, studied by reflectance measurements, showed light transmittance up to 90%, within wavelength range 400 nm-1000 nm. Nb doping also improves the field emission properties of TCO nanotubes demonstrating an order of magnitude increase in field-emitter current, compared to undoped samples.

  3. Corrosion of beryllium oxide

    International Nuclear Information System (INIS)

    Elston, J.; Caillat, R.

    1958-01-01

    Data are reported on the volatilization rate of beryllium oxide in moist air depending on temperature and water vapour concentration. They are concerned with powder samples or sintered shapes of various densities. For sintered samples, the volatilization rate is very low under the following conditions: - temperature: 1300 deg. C, - water vapour concentration in moist air: 25 g/m 3 , - flow rate: 12 I/hour corresponding to a speed of 40 m/hour on the surface of the sample. For calcinated powders (1300 deg. C), grain growth has been observed under a stream of moist air at 1100 deg. C. For instance, grain size changes from 0,5 to at least 2 microns after 500 hours of exposure at this temperature. Furthermore, results data are reported on corrosion of sintered beryllium oxide in pressurized water. At 250 deg. C, under a pressure of 40 kg/cm 2 water is very slightly corrosive; however, internal strains are revealed. Finally, some features on the corrosion in liquid sodium are exposed. (author) [fr

  4. High-productivity laser deposition welding using powder and wire. Final report of the project 'Higher efficiency of thermal coating plants by a combination of energy sources'; Hochproduktives Laser-Auftragschweissen mit Pulver und Draht. Ergebnisbericht zum Verbundvorhaben ''Wirkungsgradsteigerung thermischer Beschichtungsanlagen durch Energiequellenkombination''. SPRAYNERGY

    Energy Technology Data Exchange (ETDEWEB)

    Nowotny, Steffen (ed.)

    2013-05-01

    Excellent precision, maximum mechanical strength and selective properties of the generated coatings and 3D structures caused a breakthrough of laser deposition welding in industrial production. However, the technology is limited by its low deposition rates in those cases where large-surface components are to be coated while laser-typical corrosion and wear resistance characteristics are to be achieved. Examples are, e.g. hydraulic cylinders for offshore applications, tools for petroleum or gas production and mining, or large-scale conveyors. In these cases, modern laser hybrid technologies open up new applications. By effectively combining the laser energy with other energy sources, e.g. inductive heating, autogenic flames or electric resistance, high deposition rates are achieved with excellent coating qualities, which makes the laser process competitive also in the case of large-surface coatings. (orig./AKB) [German] Exzellente Praezision, hoechste mechanische Festigkeit und massgeschneiderte Eigenschaften von Oberflaechenschichten wie auch generativ erzeugten 3D-Strukturen: diese Merkmale haben dem Auftragschweissen mit Laserstrahlen zum Durchbruch in der industriellen Produktion verholfen. Die geringen Auftragraten setzen der Technologie jedoch in jenen Faellen Grenzen, wo es um Flaechenbeschichtungen grosser Bauteile geht, deren Einsatz aber dennoch die lasertypischen Schichteigenschaften hinsichtlich Korrosions- oder Verschleissbestaendigkeit erfordert. Beispiele sind lange Hydraulikzylinder im Offshore-Bereich, Werkzeuge der Oel- und Gasfoerderung und des Bergbaus sowie grosse Foerderschnecken. Hier erweitern moderne Laser-Hybridtechnologien wirkungsvoll die Einsatzmoeglichkeiten. Durch effiziente Kombination der Laserenergie mit anderen Energiequellen in Form induktiver Erwaermung, autogener Flammen oder elektrischem Widerstand werden hohe Auftragraten bei gleichzeitigem Erhalt der besonderen Schichtqualitaet erreicht, die das Laserverfahren auch bei

  5. Development of an early warning system for strong environmental pollution by measuring the activation of defined universally existing stress genes. Final report; Das Auftreten spezifischer Stressproteine bei Umweltbelastung in Chironomiden: Entwicklung eines neuen Fruehwarnsystems fuer starke Umweltbelastung durch Messung der Aktivierung definierter, universell vorkommender Stressgene bei ausgewaehlten Indikatororganismen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kloetzel, P.M.; Mueller, W.

    1991-12-31

    In the present pilot study we established an ELISA based detection system which allows sensitive monitoring of stress induction as a result of heavy metal pollution. The system is based on the immunological detection of the stress induced hsp70 in larvae of Chironomidae. Using this system it is possible to detect environmental pollution by heavy metals far beyond lethal toxicity values. Since only very few animals are needed the system can also be used in field tests. For poluted isopodes as Oniscus asellus for example a single animal turned out be sufficient to monitor stress induction by Pb{sup +}. The established system ought to serve as basis for a more extended study in which different animals are collected from various polluted environments and tested with respect to already induced hsp synthesis. (orig.) [Deutsch] In der vorliegenden Pilotstudie konnte ein sensitives Nachweissystem fuer die Induktion des ubiquitaeren Stresssystem durch Schwermetalle auf der Basis der immunologischen Detektion von HSP70 etabliert werden. Dieses, auf ELISA Basis arbeitende Testverfahren ermoeglicht es Schwermetallbelastungen weit unterhalb der Toxizitaetsgrenze ueber die Induktion der HSP70 Synthese in Chironomidenlarven nachzuweisen. Die Tatsache, dass nur wenige Tiere fuer eine statistische Aussage benoetigt werden laesst eine Anwendungsmoeglichkeit auch auf Freilandtiere erwarten. So reicht fuer bleibelastete Freiland-Asseln ein einziges Tier zum immunologischen Belastungsnachweis aus. Damit sind die Grundlagen fuer die zweite Phase, die Freilandphase, in welcher sowohl Freilandtiere als auch Gewaesser- und Sedimentproben von verschiedenen Standorten in die Untersuchungen miteinbezogen werden sollen; geschaffen. Es koennen jetzt Tiere aus belasteten Gewaessern bezueglich bereits erfolgter Stressproteinproduktion aber auch auf eine Neuinduzierbarkeit nach zusaetzlicher Laborbelastung untersucht werden. Ebenso koennen Labortiere auf ihre Reaktion gegenueber belasteten

  6. Buried oxide layer in silicon

    Science.gov (United States)

    Sadana, Devendra Kumar; Holland, Orin Wayne

    2001-01-01

    A process for forming Silicon-On-Insulator is described incorporating the steps of ion implantation of oxygen into a silicon substrate at elevated temperature, ion implanting oxygen at a temperature below 200.degree. C. at a lower dose to form an amorphous silicon layer, and annealing steps to form a mixture of defective single crystal silicon and polycrystalline silicon or polycrystalline silicon alone and then silicon oxide from the amorphous silicon layer to form a continuous silicon oxide layer below the surface of the silicon substrate to provide an isolated superficial layer of silicon. The invention overcomes the problem of buried isolated islands of silicon oxide forming a discontinuous buried oxide layer.

  7. Continuous lengths of oxide superconductors

    Science.gov (United States)

    Kroeger, Donald M.; List, III, Frederick A.

    2000-01-01

    A layered oxide superconductor prepared by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon. A continuous length of a second substrate ribbon is overlaid on the first substrate ribbon. Sufficient pressure is applied to form a bound layered superconductor precursor powder between the first substrate ribbon and the second substrate ribbon. The layered superconductor precursor is then heat treated to establish the oxide superconducting phase. The layered oxide superconductor has a smooth interface between the substrate and the oxide superconductor.

  8. Crystallization inhibitors for amorphous oxides

    International Nuclear Information System (INIS)

    Reznitskij, L.A.; Filippova, S.E.

    1993-01-01

    Data for the last 10 years, in which experimental results of studying the temperature stabilization of x-ray amorphous oxides (including R 3 Fe 5 O 12 R-rare earths, ZrO 2 , In 2 O 3 , Sc 2 O 3 ) and their solid solution are presented, are generalized. Processes of amorphous oxide crystallization with the production of simple oxides, solid solutions and chemical compounds with different polyhedral structure, are investigated. Energy and crystallochemical criteria for selecting the doping inhibitor-components stabilizing the amorphous state are ascertained, temperatures and enthalpies of amorpous oxide crystallization are determined, examination of certain provisions of iso,orphous miscibility theory is conducted

  9. Regulation of FoxO transcription factors by environmental NO(x). Influence of metal ions and polycyclic aromatic hydrocarbons; Regulation von FoxO-Transkriptionsfaktoren durch Umweltnoxen. Einfluss von Metallionen und polyzyklischen aromatischen Kohlenwasserstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Eckers, Anna

    2009-12-15

    FoxO transcription factors are crucial modulators of various cellular processes, controlling the expression of target genes such as those coding for manganese superoxide dismutase (MnSOD) and selenoprotein P (SeP), thereby supporting defense against oxidative stress. Environmental stimuli such as heavy metal ions and polycyclic aromatic hydrocarbons (PAH) modulate signaling pathways both by interaction with proteins or by inducing the generation of reactive oxygen species (ROS). Exposure of hepatoma cells to nickel ions at subcytotoxic doses did not translate into modulation of FoxO activity despite an activation of the Ser/Thr-kinase Akt. The cellular response to nickel ions under these conditions is most likely independent of the formation of ROS, since there were no increased levels of glutathione disulfide detectable. FoxO activity was then found to be modulated in response to exposure of cells to PAH or the tryptophan photoproduct FICZ. Both PAH and FICZ caused an increased activity of a FoxO-responsive promoter construct as well as of glucose 6-phosphatase promoter activity. In contrast, the activities of promoters of genes coding for MnSOD or SeP were decreased in response to exposure to the PAH 3-methylcholanthrene (3-MC). In line with the promoter effects, 3-MC also decreased steady-state levels of SeP mRNA. The response of the SeP promoter to 3-MC was abrogated by point mutations introduced at the two identified FoxO binding elements of the SeP promoter, implying that interaction of FoxO proteins with these sites is essential for the downregulation of promoter activity. In addition to FoxO activity being modulated by xenobiotics, it was then demonstrated that FoxO expression was also modulated by exposure of cells to PAH or FICZ. FoxO4 mRNA levels were downregulated in hepatoma cells exposed to 3-MC or FICZ. Similarly, insulin treatment caused a downregulation of mRNA levels of FoxO 1a, 3a and 4 in hepatoma cells. (orig.)

  10. Oxidation of Ethylene Carbonate on Li Metal Oxide Surfaces

    DEFF Research Database (Denmark)

    Østergaard, Thomas M.; Giordano, Livia; Castelli, Ivano Eligio

    2018-01-01

    Understanding the reactivity of the cathode surface is of key importance to the development of batteries. Here, density functional theory is applied to investigate the oxidative decomposition of the electrolyte component, ethylene carbonate (EC), on layered LixMO(2) oxide surfaces. We compare...

  11. Oxidative desulfurization of benzene fraction on transition metal oxides

    Science.gov (United States)

    Boikov, E. B.; Vishnetskaya, M. V.

    2013-02-01

    It is established that molecular oxygen is able to oxidize thiophene selectively in a mixture with benzene on V2O5 · MoO3. The introduction of thiophene inhibits the oxidation of benzene. It is shown that the conversion of thiophene during operation of the catalyst is reduced at first and then increases until it reaches its initial value.

  12. Thermal oxidation of silicon with two oxidizing species

    International Nuclear Information System (INIS)

    Vild-Maior, A.A.; Filimon, S.

    1979-01-01

    A theoretical model for the thermal oxidation of silicon in wet oxygen is presented. It is shown that the presence of oxygen in the oxidation furnace has an important effect when the water temperature is not too high (less than about 65 deg C). The model is in good agreement with the experimental data. (author)

  13. Mechanisms of electrochemical reduction and oxidation of nitric oxide

    NARCIS (Netherlands)

    Vooys, de A.C.A.; Beltramo, G.L.; Riet, van B.; Veen, van J.A.R.; Koper, M.T.M.

    2004-01-01

    A summary is given of recent work on the reactivity of nitric oxide on various metal electrodes. The significant differences between the reactivity of adsorbed NO and NO in solution are pointed out, both for the reduction and the oxidation reaction(s). Whereas adsorbed NO can be reduced only to

  14. Plutonium oxides and uranium and plutonium mixed oxides. Carbon determination

    International Nuclear Information System (INIS)

    Anon.

    Determination of carbon in plutonium oxides and uranium plutonium mixed oxides, suitable for a carbon content between 20 to 3000 ppm. The sample is roasted in oxygen at 1200 0 C, the carbon dioxide produced by combustion is neutralized by barium hydroxide generated automatically by coulometry [fr

  15. Improved Understanding of In Situ Chemical Oxidation. Technical Objective I: Contaminant Oxidation Kinetics Contaminant Oxidation Kinetics

    Science.gov (United States)

    2009-05-01

    methyl tert butyl ether NAPL non-aqueous phase liquid NOD natural oxidant demand •OH hydroxide radical Ox oxidant O3 ozone PCE...and persulfate; and Technical Objective 2, assess how soil properties (e.g., soil mineralogy , natural carbon content) affect oxidant mobility and...to develop a general description of kobs vs. T because there are many reactions that can contribute to the concentration of the reactive intermediate

  16. Ferromagnet / superconductor oxide superlattices

    Science.gov (United States)

    Santamaria, Jacobo

    2006-03-01

    The growth of heterostructures combining oxide materials is a new strategy to design novel artificial multifunctional materials with interesting behaviors ruled by the interface. With the (re)discovery of colossal magnetoresistance (CMR) materials, there has been renewed interest in heterostructures involving oxide superconductors and CMR ferromagnets where ferromagnetism (F) and superconductivity (S) compete within nanometric distances from the interface. In F/S/F structures involving oxides, interfaces are especially complex and various factors like interface disorder and roughness, epitaxial strain, polarity mismatch etc., are responsible for depressed magnetic and superconducting properties at the interface over nanometer length scales. In this talk I will focus in F/S/F structures made of YBa2Cu3O7 (YBCO) and La0.7Ca0.3MnO3 (LCMO). The high degree of spin polarization of the LCMO conduction band, together with the d-wave superconductivity of the YBCO make this F/S system an adequate candidate for the search of novel spin dependent effects in transport. We show that superconductivity at the interface is depressed by various factors like charge transfer, spin injection or ferromagnetic superconducting proximity effect. I will present experiments to examine the characteristic distances of the various mechanisms of superconductivity depression. In particular, I will discuss that the critical temperature of the superconductor depends on the relative orientation of the magnetization of the F layers, giving rise to a new giant magnetoresistance effect which might be of interest for spintronic applications. Work done in collaboration with V. Peña^1, Z. Sefrioui^1, J. Garcia-Barriocanal^1, C. Visani^1, D. Arias^1, C. Leon^1 , N. Nemes^2, M. Garcia Hernandez^2, S. G. E. te Velthuis^3, A. Hoffmann^3, M. Varela^4, S. J. Pennycook^4. Work supported by MCYT MAT 2005-06024, CAM GR- MAT-0771/2004, UCM PR3/04-12399 Work at Argonne supported by the Department of Energy, Basic

  17. Characterization of tin oxide nanoparticles synthesized via oxidation from metal

    International Nuclear Information System (INIS)

    Abruzzi, R.C.; Dedavid, B.A.; Pires, M.J.R.; Streicher, M.

    2014-01-01

    The tin oxide (SnO_2) is a promising material with great potential for applications such as gas sensors and catalysts. This oxide nanostructures show higher activation efficiency due to its larger effective surface. This paper presents the synthesis and characterization of the tin oxide in different conditions, via oxidation of pure tin with nitric acid. Results obtained from the characterization of SnO_2 powder by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDX), Particle size by Dynamic Light Scattering (DLS) and Infrared Spectroscopy (FTIR) indicated that the conditions were suitable for the synthesis to obtain manometric tin oxide granules with crystalline structure of rutile. (author)

  18. Direct Coal Oxidation in Modified Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Deleebeeck, Lisa; Gil, Vanesa; Ippolito, Davide

    2015-01-01

    Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon-carbonate s......Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon......-carbonate slurry or anode layer. The nature of the coal affects both open circuit voltage and power output. Highest OCV and power densities were observed for bituminous coal and by adding manganese oxide or praseodymium-doped ceria to the carbon/carbonate mixture. Comparing the carbon black fueled performance...... bituminous coal (73 mW/cm2). © 2015 ECS - The Electrochemical Society...

  19. Direct Coal Oxidation in Modified Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Deleebeeck, Lisa; Gil, Vanesa; Ippolito, Davide

    2017-01-01

    Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon-carbonate s......Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon......-carbonate slurry or anode layer. The nature of the coal affects both open circuit voltage and power output. Highest OCV and power densities were observed for bituminous coal and by adding manganese oxide or praseodymium-doped ceria to the carbon/carbonate mixture. Comparing the carbon black fueled performance...... bituminous coal (73 mW/cm2)....

  20. Hydrogen oxidation in Azospirillum brasilense

    Energy Technology Data Exchange (ETDEWEB)

    Tibelius, K.

    1984-01-01

    Hydrogen oxidation by Azospirillum brasilense Sp7 was studied in N/sub 2/-fixing and NH/sub 4//sup +/-grown batch cultures. The K/sub m/ for H/sub 2/ of O/sub 2/-dependent H/sup 3/H oxidation in whole cells was 9 uM. The rates of H/sup 3/H and H/sub 2/ oxidation were very similar, indicating that the initial H/sub 2/ activation step in the overall H/sub 2/ oxidation reaction was not rate-limiting and that H/sup 3/H oxidation was a valid measure of H/sub 2/-oxidation activity. Hydrogen-oxidation activity was inhibited irreversibly by air. In N-free cultures the O/sub 2/ optima for O/sub 2/-dependent H/sub 2/ oxidation, ranging from 0.5-1.25% O/sub 2/ depending on the phase of growth, were significantly higher than those of C/sub 2/H/sub 2/ reduction, 0.15-0.35%, suggesting that the H/sub 2/-oxidation system may have a limited ability to aid in the protection of nitrogenase against inactivation by O/sub 2/. Oxygen-dependent H/sub 2/ oxidation was inhibited by NO/sub 2//sup +/, NO, CO, and C/sub 2/H/sub 2/ with apparent K/sub 1/ values of 20, 0.4, 28, and 88 uM, respectively. Hydrogen-oxidation activity was 50 to 100 times higher in denitrifying cultures when the terminal electron acceptor for growth was N/sub 2/O rather than NO/sub 3//sup -/, possibly due to the irreversible inhibition of hydrogenase by NO/sub 2//sup -/ and NO in NO/sub 3//sup -/-grown cultures.

  1. Operation of staged membrane oxidation reactor systems

    Science.gov (United States)

    Repasky, John Michael

    2012-10-16

    A method of operating a multi-stage ion transport membrane oxidation system. The method comprises providing a multi-stage ion transport membrane oxidation system with at least a first membrane oxidation stage and a second membrane oxidation stage, operating the ion transport membrane oxidation system at operating conditions including a characteristic temperature of the first membrane oxidation stage and a characteristic temperature of the second membrane oxidation stage; and controlling the production capacity and/or the product quality by changing the characteristic temperature of the first membrane oxidation stage and/or changing the characteristic temperature of the second membrane oxidation stage.

  2. Effects of Oxidation on Oxidation-Resistant Graphite

    Energy Technology Data Exchange (ETDEWEB)

    Windes, William [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smith, Rebecca [Idaho National Lab. (INL), Idaho Falls, ID (United States); Carroll, Mark [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    The Advanced Reactor Technology (ART) Graphite Research and Development Program is investigating doped nuclear graphite grades that exhibit oxidation resistance through the formation of protective oxides on the surface of the graphite material. In the unlikely event of an oxygen ingress accident, graphite components within the VHTR core region are anticipated to oxidize so long as the oxygen continues to enter the hot core region and the core temperatures remain above 400°C. For the most serious air-ingress accident which persists over several hours or days the continued oxidation can result in significant structural damage to the core. Reducing the oxidation rate of the graphite core material during any air-ingress accident would mitigate the structural effects and keep the core intact. Previous air oxidation testing of nuclear-grade graphite doped with varying levels of boron-carbide (B4C) at a nominal 739°C was conducted for a limited number of doped specimens demonstrating a dramatic reduction in oxidation rate for the boronated graphite grade. This report summarizes the conclusions from this small scoping study by determining the effects of oxidation on the mechanical strength resulting from oxidation of boronated and unboronated graphite to a 10% mass loss level. While the B4C additive did reduce mechanical strength loss during oxidation, adding B4C dopants to a level of 3.5% or more reduced the as-fabricated compressive strength nearly 50%. This effectively minimized any benefits realized from the protective film formed on the boronated grades. Future work to infuse different graphite grades with silicon- and boron-doped material as a post-machining conditioning step for nuclear components is discussed as a potential solution for these challenges in this report.

  3. High temperature oxidation resistant cermet compositions

    Science.gov (United States)

    Phillips, W. M. (Inventor)

    1976-01-01

    Cermet compositions are designed to provide high temperature resistant refractory coatings on stainless steel or molybdenum substrates. A ceramic mixture of chromium oxide and aluminum oxide form a coating of chromium oxide as an oxidation barrier around the metal particles, to provide oxidation resistance for the metal particles.

  4. 21 CFR 184.1545 - Nitrous oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Nitrous oxide. 184.1545 Section 184.1545 Food and... Substances Affirmed as GRAS § 184.1545 Nitrous oxide. (a) Nitrous oxide (empirical formula N2O, CAS Reg. No.... Nitrous oxide is manufactured by the thermal decomposition of ammonium nitrate. Higher oxides of nitrogen...

  5. Optical properties and electronic transitions of zinc oxide, ferric oxide, cerium oxide, and samarium oxide in the ultraviolet and extreme ultraviolet

    DEFF Research Database (Denmark)

    Pauly, N; Yubero, F; Espinós, J P

    2017-01-01

    Optical properties and electronic transitions of four oxides, namely zinc oxide, ferric oxide, cerium oxide, and samarium oxide, are determined in the ultraviolet and extreme ultraviolet by reflection electron energy loss spectroscopy using primary electron energies in the range 0.3-2.0 ke...

  6. Uranium oxide recovering method

    International Nuclear Information System (INIS)

    Ota, Kazuaki; Takazawa, Hiroshi; Teramae, Naoki; Onoue, Takeshi.

    1997-01-01

    Nitrates containing uranium nitrate are charged in a molten salt electrolytic vessel, and a heat treatment is applied to prepare molten salts. An anode and a cathode each made of a graphite rod are disposed in the molten salts. AC voltage is applied between the anode and the cathode to conduct electrolysis of the molten salts. Uranium oxides are deposited as a recovered product of uranium, on the surface of the anode. The nitrates containing uranium nitrate are preferably a mixture of one or more nitrates selected from sodium nitrate, potassium nitrate, calcium nitrate and magnesium nitrate with uranium nitrate. The nitrates may be liquid wastes of nitrates. The temperature for the electrolysis of the molten salts is preferably from 150 to 300degC. The voltage for the electrolysis of the molten salts is preferably an AC voltage of from 2 to 6V, more preferably from 4 to 6V. (I.N.)

  7. Solid Oxide Electrolyser Cell

    DEFF Research Database (Denmark)

    Jensen, Søren Højgaard

    Solid oxide fuel cells (SOFCs) produced at Risø National Laboratory was tested as steam electrolysers under various current densities, operating temperatures and steam partial pressures. At 950 °C and a cell voltage of 1.48V the current density was -3.6A/cm2 with app. 30% H2 + 70% H2O in the inlet...... it is possible to achieve a production price of 0.7 US$/kg H2 with an electricity price of 1.3 US¢/kWh. The cell voltage was measured as function of time. In test ofabout two month of duration a long-term degradation was observed. At 850 °C, -0.5 A/cm2 with 50 vol% H2 the degradation rate was app. 20 mV/1000h...

  8. Uranium plutonium oxide fuels

    International Nuclear Information System (INIS)

    Cox, C.M.; Leggett, R.D.; Weber, E.T.

    1981-01-01

    Uranium plutonium oxide is the principal fuel material for liquid metal fast breeder reactors (LMFBR's) throughout the world. Development of this material has been a reasonably straightforward evolution from the UO 2 used routinely in the light water reactor (LWR's); but, because of the lower neutron capture cross sections and much lower coolant pressures in the sodium cooled LMFBR's, the fuel is operated to much higher discharge exposures than that of a LWR. A typical LMFBR fuel assembly is shown. Depending on the required power output and the configuration of the reactor, some 70 to 400 such fuel assemblies are clustered to form the core. There is a wide variation in cross section and length of the assemblies where the increasing size reflects a chronological increase in plant size and power output as well as considerations of decreasing the net fuel cycle cost. Design and performance characteristics are described

  9. Thermal and oxidation effects

    Energy Technology Data Exchange (ETDEWEB)

    Adamcova, J.; Kolaoikova, I. [Prague Univ., Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles (Czech Republic); Adamcova, J. [Czech Geological Survey, Geologicka 6, Prague (Czech Republic); Kaufhold, S.; Dohrmann, R. [BGR, Federal Institute for Geoscience and Natural Resources, Hannover (Germany); Dohrmann, R. [LBEG, State Authority for Mining, Energy, and Geology, Hannover (Germany); Craen, M. de; Van Geet, M.; Honty, M.; Wang, L.; Weetjens, E. [CK-CEN - Belgian Nuclear Research Centre - Environment, Healt and Safety Institute, Mol (Belgium); Van Geet, M. [ONDRAF/NIRAS - Belgian Agency for Radioactive Waste and Enriched Fissile Materials, Brussel (Belgium); Pozzi, J.P.; Janots, D. [Ecole Normale Paris, CNRS Lab. de Geologie, 75 - Paris (France); Aubourg, C. [Universite Cergy Pontoise, CNRS Lab. de Tectonique, 95 (France); Cathelineau, M.; Rousset, D.; Ruck, R. [Nancy-1 Univ. Henri Poincare, CNRS G2R, 54 (France); Clauer, N. [Strasbourg-1 Univ., CNRS CGS, 67 (France); Liewig, N. [Institut Pluridisciplinaire Hubert Curien, CNRS, 67 - Strasbourg (France); Techer, I. [Nimes Univ., CNRS Cerege, 30 (France)

    2007-07-01

    This session gathers 4 articles dealing with: the alteration processes in bentonites: mineralogical and structural changes during long-term and short-term experiments (J. Adamcov, I. Kolarikova); the implications from the lot experiment regarding the selection of an optimum HLRW bentonite (S. Kaufhold, R. Dohrmann); the extent of oxidation in Boom clay as a result of excavation and ventilation of the HADES URF: Experimental and modelling assessments (M. De Craen, M. Van Geet, M. Honty, L. Wang, E. Weetjens); and the magnetic and mineralogical alterations under thermal stress at 95 deg. C of Callovo-Oxfordian clay-stones (Bure, France) and lower Dogger Mont Terri clay-stones, Switzerland (J.P. Pozzi, C. Aubourg, D. Janots, M. Cathelineau, N. Clauer, D. Rousset, R. Ruck, N. Liewig, I. Techer)

  10. Computer simulation of oxides

    International Nuclear Information System (INIS)

    Rowley, A.

    1998-01-01

    An ionic interaction model is developed which accounts for the effects of the ionic environment upon the electron densities of both cations and anions through changes in their size and shape and is transferable between materials. These variations are represented by additional dynamical variables which are handled within the model using the techniques of the Car-Parrinello method. The model parameters are determined as far as possible by input from external ab initio electronic structure calculations directed at examining the individual effects of the ionic environment upon the ions, particularly the oxide ion. Techniques for the evaluation of dipolar and quadrupolar Ewald sums in non-cubic simulation cells and the calculation of the pressure due to the terms in the potential are presented. This model is applied to the description of the perfect crystal properties and phonon dispersion curves of MgO. Consideration of the high symmetry phonon modes allows parameterization of the remaining model parameters in an unambiguous fashion. The same procedure is used to obtain parameters for CaO. These two parameter sets are examined to determine how they may be used to generate the parameters for SrO and simple scaling relationships based on ionic radii and polarizabilities are formulated. The transferability of the model to Cr 2 O 3 is investigated using parameters generated from the alkaline earth oxides. The importance of lower symmetry model terms, particularly quadrupolar interactions, at the low symmetry ion sites in the crystal structure is demonstrated. The correct ground-state crystal structure is predicted and the calculated surface energies and relaxation phenomena are found to agree well with previous ab initio studies. The model is applied to GeO 2 as a strong test of its applicability to ion environments far different from those encountered in MgO. An good description of the crystal structures is obtained and the interplay of dipolar and quadrupolar effects is

  11. Nanoroses of nickel oxides: Synthesis, electron tomography study, and application in CO oxidation and energy storage

    KAUST Repository

    Fihri, Aziz; Sougrat, Rachid; Baby, Rakhi Raghavan; Rahal, Raed; Cha, Dong Kyu; Hedhili, Mohamed N.; Bouhrara, Mohamed; Alshareef, Husam N.; Polshettiwar, Vivek

    2012-01-01

    Nickel oxide and mixed-metal oxide structures were fabricated by using microwave irradiation in pure water. The nickel oxide self-assembled into unique rose-shaped nanostructures. These nickel oxide roses were studied by performing electron

  12. Nitrous oxide and perioperative outcomes.

    Science.gov (United States)

    Ko, Hanjo; Kaye, Alan David; Urman, Richard D

    2014-06-01

    There is emerging evidence related to the effects of nitrous oxide on important perioperative patient outcomes. Proposed mechanisms include metabolic effects linked to elevated homocysteine levels and endothelial dysfunction, inhibition of deoxyribonucleic acid and protein formation, and depression of chemotactic migration by monocytes. Newer large studies point to possible risks associated with the use of nitrous oxide, although data are often equivocal and inconclusive. Cardiovascular outcomes such as stroke or myocardial infarction were shown to be unchanged in previous studies, but the more recent Evaluation of Nitrous Oxide in the Gas Mixture for Anesthesia I trial shows possible associations between nitrous oxide and increased cardiovascular and pulmonary complications. There are also possible effects on postoperative wound infections and neuropsychological function, although the multifactorial nature of these complications should be considered. Teratogenicity linked to nitrous oxide use has not been firmly established. The use of nitrous oxide for routine anesthetic care may be associated with significant costs if complications such as nausea, vomiting, and wound infections are taken into consideration. Overall, definitive data regarding the effect of nitrous oxide on major perioperative outcomes are lacking. There are ongoing prospective studies that may further elucidate its role. The use of nitrous oxide in daily practice should be individualized to each patient's medical conditions and risk factors.

  13. Modern chemistry of nitrous oxide

    International Nuclear Information System (INIS)

    Leont'ev, Aleksandr V; Fomicheva, Ol'ga A; Proskurnina, Marina V; Zefirov, Nikolai S

    2001-01-01

    Modern trends of the chemistry of nitrous oxide are discussed. Data on its structure, physical properties and reactivity are generalised. The effect of N 2 O on the environment and the possibility of its utilisation are considered. Attention is focused on the processes in which the oxidising potential of nitrous oxide can be employed. The bibliography includes 329 references.

  14. on THICKNESS OF COPPER (|) OXIDE

    African Journals Online (AJOL)

    2006-12-20

    Dec 20, 2006 ... known materials to be used as semiconductor devices. The oxide is. Observed to be an attractive starting material for the production of solar cells for low cost terrestrial conversion of solar energy to electricity. Copper (I) oxide is one Of the earliest known photovoltaic materials and the first in which the ...

  15. BRCA1 and Oxidative Stress

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Yong Weon; Kang, Hyo Jin [Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057 (United States); Bae, Insoo, E-mail: ib42@georgetown.edu [Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057 (United States); Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057 (United States)

    2014-04-03

    The breast cancer susceptibility gene 1 (BRCA1) has been well established as a tumor suppressor and functions primarily by maintaining genome integrity. Genome stability is compromised when cells are exposed to oxidative stress. Increasing evidence suggests that BRCA1 regulates oxidative stress and this may be another mechanism in preventing carcinogenesis in normal cells. Oxidative stress caused by reactive oxygen species (ROS) is implicated in carcinogenesis and is used strategically to treat human cancer. Thus, it is essential to understand the function of BRCA1 in oxidative stress regulation. In this review, we briefly summarize BRCA1’s many binding partners and mechanisms, and discuss data supporting the function of BRCA1 in oxidative stress regulation. Finally, we consider its significance in prevention and/or treatment of BRCA1-related cancers.

  16. Nanotoxicology of Metal Oxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    Amedea B. Seabra

    2015-06-01

    Full Text Available This review discusses recent advances in the synthesis, characterization and toxicity of metal oxide nanoparticles obtained mainly through biogenic (green processes. The in vitro and in vivo toxicities of these oxides are discussed including a consideration of the factors important for safe use of these nanomaterials. The toxicities of different metal oxide nanoparticles are compared. The importance of biogenic synthesized metal oxide nanoparticles has been increasing in recent years; however, more studies aimed at better characterizing the potent toxicity of these nanoparticles are still necessary for nanosafely considerations and environmental perspectives. In this context, this review aims to inspire new research in the design of green approaches to obtain metal oxide nanoparticles for biomedical and technological applications and to highlight the critical need to fully investigate the nanotoxicity of these particles.

  17. Selective catalytic oxidation of ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Leppaelahti, J; Koljonen, T [VTT Energy, Espoo (Finland)

    1997-12-31

    In the combustion of fossil fuels, the principal source of nitrogen oxides is nitrogen bound in the fuel structure. In gasification, a large part of fuel nitrogen forms NH{sub 3}, which may form nitrogen oxides during gas combustion. If NH{sub 3} and other nitrogen species could be removed from hot gas, the NO emission could be considerably reduced. However, relatively little attention has been paid to finding new means of removing nitrogen compounds from the hot gasification gas. The possibility of selectively oxidizing NH{sub 3} to N{sub 2} in the hot gasification has been studied at VTT Energy. The largest NH{sub 3} reductions have been achieved by catalytic oxidation on aluminium oxides. (author) (4 refs.)

  18. Selective catalytic oxidation of ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Leppaelahti, J.; Koljonen, T. [VTT Energy, Espoo (Finland)

    1996-12-31

    In the combustion of fossil fuels, the principal source of nitrogen oxides is nitrogen bound in the fuel structure. In gasification, a large part of fuel nitrogen forms NH{sub 3}, which may form nitrogen oxides during gas combustion. If NH{sub 3} and other nitrogen species could be removed from hot gas, the NO emission could be considerably reduced. However, relatively little attention has been paid to finding new means of removing nitrogen compounds from the hot gasification gas. The possibility of selectively oxidizing NH{sub 3} to N{sub 2} in the hot gasification has been studied at VTT Energy. The largest NH{sub 3} reductions have been achieved by catalytic oxidation on aluminium oxides. (author) (4 refs.)

  19. Exploring oxidative modifications of tyrosine

    DEFF Research Database (Denmark)

    Houée-Lévin, C; Bobrowski, K; Horakova, L

    2015-01-01

    residues are oxidised in vivo with impact on cellular homeostasis and redox signalling pathways. A notable example is tyrosine, which can undergo a number of oxidative post-translational modifications to form 3-hydroxy-tyrosine, tyrosine crosslinks, 3-nitrotyrosine and halogenated tyrosine, with different...... effects on cellular functions. Tyrosine oxidation has been studied extensively in vitro, and this has generated detailed information about the molecular mechanisms that may occur in vivo. An important aspect of studying tyrosine oxidation both in vitro and in biological systems is the ability to monitor...... residues modified and the nature of the modification. These approaches have helped understanding of the consequences of tyrosine oxidation in biological systems, especially its effects on cell signalling and cell dysfunction, linking to roles in disease. There is mounting evidence that tyrosine oxidation...

  20. Superparamagnetic iron oxides for MRI

    International Nuclear Information System (INIS)

    Weissleder, R.; Reimer, P.

    1993-01-01

    Pharmaceutical iron oxide preparations have been used as MRI contrast agents for a variety of purposes. These agents predominantly decrease T2 relaxation times and therefore cause a decrease in signal intensity of tissues that contain the agent. After intravenous administration, dextran-coated iron oxides typically accumulate in phagocytic cells in liver and spleen. Clinical trials have shown that iron oxide increases lesion/liver and lesion/spleen contrast, that more lesions can be depicted than on plain MRI or CT, and that the size threshold for lesion detection decreases. Decreased uptake of iron oxides in liver has been observed in hepatitis and cirrhosis, potentially allowing the assessment of organ function. More recently a variety of novel, target-specific monocrystalline iron oxides compounds have been used for receptor and immunospecific images. Future development of targeted MRI contrast agents is critical for organ- or tissue-specific quantitative and functional MRI. (orig.)

  1. Superparamagnetic iron oxides for MRI

    Energy Technology Data Exchange (ETDEWEB)

    Weissleder, R [MGH-NMR Center, Dept. of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Reimer, P [MGH-NMR Center, Dept. of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); [Inst. fuer Klinische Radiologie, Zentrale Roentgendiagnostik, Westfaelische-Wilhelms-Univ., Muenster (Germany)

    1993-06-01

    Pharmaceutical iron oxide preparations have been used as MRI contrast agents for a variety of purposes. These agents predominantly decrease T2 relaxation times and therefore cause a decrease in signal intensity of tissues that contain the agent. After intravenous administration, dextran-coated iron oxides typically accumulate in phagocytic cells in liver and spleen. Clinical trials have shown that iron oxide increases lesion/liver and lesion/spleen contrast, that more lesions can be depicted than on plain MRI or CT, and that the size threshold for lesion detection decreases. Decreased uptake of iron oxides in liver has been observed in hepatitis and cirrhosis, potentially allowing the assessment of organ function. More recently a variety of novel, target-specific monocrystalline iron oxides compounds have been used for receptor and immunospecific images. Future development of targeted MRI contrast agents is critical for organ- or tissue-specific quantitative and functional MRI. (orig.)

  2. Selective carbon monoxide oxidation over Ag-based composite oxides

    Energy Technology Data Exchange (ETDEWEB)

    Guldur, C. [Gazi University, Ankara (Turkey). Chemical Engineering Department; Balikci, F. [Gazi University, Ankara (Turkey). Institute of Science and Technology, Environmental Science Department

    2002-02-01

    We report our results of the synthesis of 1 : 1 molar ratio of the silver cobalt and silver manganese composite oxide catalysts to remove carbon monoxide from hydrogen-rich fuels by the catalytic oxidation reaction. Catalysts were synthesized by the co-precipitation method. XRD, BET, TGA, catalytic activity and catalyst deactivation studies were used to identify active catalysts. Both CO oxidation and selective CO oxidation were carried out in a microreactor using a reaction gas mixture of 1 vol% CO in air and another gas mixture was prepared by mixing 1 vol% CO, 2 vol% O{sub 2}, 84 vol% H{sub 2}, the balance being He. 15 vol% CO{sub 2} was added to the reactant gas mixture in order to determine the effect of CO{sub 2}, reaction gases were passed through the humidifier to determine the effect of the water vapor on the oxidation reaction. It was demonstrated that metal oxide base was decomposed to the metallic phase and surface areas of the catalysts were decreased when the calcination temperature increased from 200{sup o}C to 500{sup o}C. Ag/Co composite oxide catalyst calcined at 200{sup o}C gave good activity at low temperatures and 90% of CO conversion at 180{sup o}C was obtained for the selective CO oxidation reaction. The addition of the impurities (CO{sub 2} or H{sub 2}O) decreased the activity of catalyst for selective CO oxidation in order to get highly rich hydrogen fuels. (author)

  3. Oxide ultrathin films science and technology

    CERN Document Server

    Pacchioni, Gianfranco

    2012-01-01

    A wealth of information in one accessible book. Written by international experts from multidisciplinary fields, this in-depth exploration of oxide ultrathin films covers all aspects of these systems, starting with preparation and characterization, and going on to geometrical and electronic structure, as well as applications in current and future systems and devices. From the Contents: Synthesis and Preparation of Oxide Ultrathin Films Characterization Tools of Oxide Ultrathin Films Ordered Oxide Nanostructures on Metal Surfaces Unusual Properties of Oxides and Other Insulators in the Ultrathin Limit Silica and High-K Dielectrics Thin Films in Microelectronics Oxide Passive Films and Corrosion Protection Oxide Films as Catalytic Materials and as Models of Real Catalysts Oxide Films in Spintronics Oxide Ultrathin Films in Solid Oxide Fuel Cells Transparent Conducting and Chromogenic Oxide Films as Solar Energy Materials Oxide Ultrathin Films in Sensor Applications Ferroelectricity in Ultrathin Film Capacitors T...

  4. Catalyst for Decomposition of Nitrogen Oxides

    Science.gov (United States)

    Schryer, David R. (Inventor); Jordan, Jeffrey D. (Inventor); Akyurtlu, Ates (Inventor); Akyurtlu, Jale (Inventor)

    2015-01-01

    This invention relates generally to a platinized tin oxide-based catalyst. It relates particularly to an improved platinized tin oxide-based catalyst able to decompose nitric oxide to nitrogen and oxygen without the necessity of a reducing gas.

  5. Test Concept for Advanced Oxidation Techniques

    DEFF Research Database (Denmark)

    Bennedsen, Lars Rønn; Søgaard, Erik Gydesen; Mortensen, Lars

    advanced on-site oxidation tests. The remediation techniques included are electrochemical oxidation, photochemical/photocatalytic oxidation, ozone, hydrogen peroxide, permanganate, and persulfate among others. A versatile construction of the mobile test unit makes it possible to combine different...

  6. Treatment of Fatty Acid Oxidation Disorders

    Science.gov (United States)

    ... Treatment of fatty acid oxidation disorders Treatment of fatty acid oxidation disorders E-mail to a friend Please ... this page It's been added to your dashboard . Fatty acid oxidation disorders are rare health conditions that affect ...

  7. Trends for Methane Oxidation at Solid Oxide Fuel Cell Conditions

    DEFF Research Database (Denmark)

    Kleis, Jesper; Jones, Glenn; Abild-Pedersen, Frank

    2009-01-01

    First-principles calculations are used to predict a plausible reaction pathway for the methane oxidation reaction. In turn, this pathway is used to obtain trends in methane oxidation activity at solid oxide fuel cell (SOFC) anode materials. Reaction energetics and barriers for the elementary...... the Ni surfaces to other metals of interest. This allows the reactivity over the different metals to be understood in terms of two reactivity descriptors, namely, the carbon and oxygen adsorption energies. By combining a simple free-energy analysis with microkinetic modeling, activity landscapes of anode...

  8. Electrochemical Thinning for Anodic Aluminum Oxide and Anodic Titanium Oxide

    Energy Technology Data Exchange (ETDEWEB)

    Lee, In Hae; Jo, Yun Kyoung; Kim, Yong Tae; Tak, Yong Sug; Choi, Jin Sub [Inha University, Incheon (Korea, Republic of)

    2012-05-15

    For given electrolytes, different behaviors of anodic aluminum oxide (AAO) and anodic titanium oxide (ATO) during electrochemical thinning are explained by ionic and electronic current modes. Branched structures are unavoidably created in AAO since the switch of ionic to electronic current is slow, whereas the barrier oxide in ATO is thinned without formation of the branched structures. In addition, pore opening can be possible in ATO if chemical etching is performed after the thinning process. The thinning was optimized for complete pore opening in ATO and potential-current behavior is interpreted in terms of ionic current-electronic current switching.

  9. Mesoporous Transition Metal Oxides for Supercapacitors

    OpenAIRE

    Wang, Yan; Guo, Jin; Wang, Tingfeng; Shao, Junfeng; Wang, Dong; Yang, Ying-Wei

    2015-01-01

    Recently, transition metal oxides, such as ruthenium oxide (RuO2), manganese dioxide (MnO2), nickel oxides (NiO) and cobalt oxide (Co3O4), have been widely investigated as electrode materials for pseudo-capacitors. In particular, these metal oxides with mesoporous structures have become very hot nanomaterials in the field of supercapacitors owing to their large specific surface areas and suitable pore size distributions. The high specific capacities of these mesoporous metal oxides are result...

  10. The oxidation and corrosion of ODS alloys

    Science.gov (United States)

    Lowell, Carl E.; Barrett, Charles A.

    1990-01-01

    The oxidation and hot corrosion of high temperature oxide dispersion strengthened (ODS) alloys are reviewed. The environmental resistance of such alloys are classified by oxide growth rate, oxide volatility, oxide spalling, and hot corrosion limitations. Also discussed are environmentally resistant coatings for ODS materials. It is concluded that ODS NiCrAl and FeCrAl alloys are highly oxidation and corrosion resistant and can probably be used uncoated.

  11. Oxidation And Hot Corrosion Of ODS Alloy

    Science.gov (United States)

    Lowell, Carl E.; Barrett, Charles A.

    1993-01-01

    Report reviews oxidation and hot corrosion of oxide-dispersion-strengthened (ODS) alloys, intended for use at high temperatures. Classifies environmental resistances of such alloys by rates of growth of oxides, volatilities of oxides, spalling of oxides, and limitations imposed by hot corrosion. Also discusses environmentally resistant coatings for ODS materials. Concludes ODS NICrAl and FeCrAl alloys highly resistant to oxidation and corrosion and can be used uncoated.

  12. Harmful loading of water courses caused by precipitation. Phase 2. Part project 8: Loading of harmful substances by precipitation. Pt. A, B, and C. Pt. A: Harmful substances introduced by atmospheric deposition dust.Pt. B: Sources and mobility of harmful substances. Pt. C: Load of harmful substances from roof and road surfaces; NIEDERschlagsbedingte SCHadstoffbeLAstung der Gewaesser - Phase 2. Teilprojekt 8: Schadstoffbelastung durch Niederschlag. T. A, B und C. T. A: Schadstoffeintrag durch atmosphaerische Staubdeposition. T. B: Quellen und Mobilitaet von Schadstoffen. T. C: Schadstofffrachten von Dach- und Strassenflaechen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Luetzner, K.; Grothkopp, H.; Gebhard, V.; Rennert, S.; Huth, B.

    1997-02-28

    Stadtgebieten ist die Belastung der Oberflaechenabfluesse nicht allein von der Verkehrsdichte abhaengig. Dies gilt hoechstens ueber die Partikelbeladung hinsichtlich einiger Elemente. Das Fahrverhalten, z.B. haeufiges Anfahren und Bremsen, ist hier ebenso von Bedeutung. Weiterhin beeinflussen die Hintergrundbelastung, Abspuelungen von unbefestigten Flaechen sowie weitere Aktivitaeten (z.B. intensive Bautaetigkeit) die Belastung von Nebenstrassen. Im Verlauf der untersuchten Niederschlagsereignisse war nach ca. 6 mm Niederschlag die Auswaschung der bodennahen Luftschicht beendet. Nach einem gefallenen Niederschlag von jeweils 15 mm konnte bei zwei Ereignissen die nahezu vollstaendige Abspuelung der partikulaeren Fracht festgestellt werden. Rund 80% der Schwermetallbelastung (bei Cu nur ca. 50%) des Einzugsgebietes werden durch die Emissionen des Strassenverkehrs verursacht. Kupferdaecher emittieren rund 40% der Cu-Fracht. Die Schwermetallfracht der Dachabfluessen ist ueberwiegend in der fluessigen Phase enthalten (ausser Pb, Fe), dagegen ist die Fracht der Strassenabfluesse zu ueber 90% partikulaer gebunden. Ein Rueckhalt dieser Schwermetallfracht koennte somit ueber den AFS-Rueckhalt geschehen. Entsprechend der durchgefuehrten Berechnung auf Grundlage bekannter Mittelwerte entfernt die Stadtreinigung Dresden gegenwaertig etwa die Haelfte der Fe- und Ni-Gesamtfracht sowie rund 40% der Cu-, Pb- und Zn-Gesamtfracht des Einzugsgebietes. (orig./AJ)

  13. Oxidation kinetics of corium pool

    Energy Technology Data Exchange (ETDEWEB)

    Sulatsky, A.A., E-mail: andrei314@mail.ru [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation); Smirnov, S.A. [D.V. Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA), St. Petersburg (Russian Federation); Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Kotova, S.Yu. [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation); Fischer, M.; Hellmann, S. [AREVA NP GmbH, Erlangen (Germany); Tromm, W.; Miassoedov, A. [Forschungzentrum Karlsruhe (FZK), Karlsruhe (Germany); Bottomley, D. [EUROPÄISCHE KOMMISSION, Joint Research Centre Institut für Transurane (ITU), Karlsruhe (Germany); Piluso, P. [CEA Cadarache-DEN/DTN/STRI, St.Paul-lez-Durance (France); Barrachin, M. [Institut de Radioprotection et Sûreté Nucléaire, St.Paul-lez-Durance (France)

    2013-09-15

    Highlights: • The analysis of experimental data on molten corium oxidation was been carried out. • The analysis has revealed the main factors influencing the oxidation kinetics. • The analysis was used for developing a qualitative analytical model. • The numerical modeling has confirmed the results of experimental data analysis. -- Abstract: Experimental, theoretical and numerical studies of oxidation kinetics of an open surface corium pool have been reported. The experiments have been carried out within OECD MASCA program and ISTC METCOR, METCOR-P and EVAN projects. It has been shown that the melt oxidation is controlled by an oxidant supply to the melt free surface from the atmosphere, not by the reducer supply from the melt. The project experiments have not detected any input of the zirconium oxidation kinetics into the process chemistry. The completed analysis puts forward a simple analytical model, which gives an explanation of the main features of melt oxidation process. The numerical modeling results are in good agreement with experimental data and theoretical considerations.

  14. Oxidation kinetics of corium pool

    International Nuclear Information System (INIS)

    Sulatsky, A.A.; Smirnov, S.A.; Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Kotova, S.Yu.; Fischer, M.; Hellmann, S.; Tromm, W.; Miassoedov, A.; Bottomley, D.; Piluso, P.; Barrachin, M.

    2013-01-01

    Highlights: • The analysis of experimental data on molten corium oxidation was been carried out. • The analysis has revealed the main factors influencing the oxidation kinetics. • The analysis was used for developing a qualitative analytical model. • The numerical modeling has confirmed the results of experimental data analysis. -- Abstract: Experimental, theoretical and numerical studies of oxidation kinetics of an open surface corium pool have been reported. The experiments have been carried out within OECD MASCA program and ISTC METCOR, METCOR-P and EVAN projects. It has been shown that the melt oxidation is controlled by an oxidant supply to the melt free surface from the atmosphere, not by the reducer supply from the melt. The project experiments have not detected any input of the zirconium oxidation kinetics into the process chemistry. The completed analysis puts forward a simple analytical model, which gives an explanation of the main features of melt oxidation process. The numerical modeling results are in good agreement with experimental data and theoretical considerations

  15. Alumina composites for oxide/oxide fibrous monoliths

    International Nuclear Information System (INIS)

    Cruse, T. A.; Polzin, B. J.; Picciolo, J. J.; Singh, D.; Tsaliagos, R. N.; Goretta, K. C.

    2000-01-01

    Most work on ceramic fibrous monoliths (FMs) has focused on the Si 3 N 4 /BN system. In an effort to develop oxidation-resistant FMs, several oxide systems have recently been examined. Zirconia-toughened alumina and alumina/mullite appear to be good candidates for the cell phase of FMs. These composites offer higher strength and toughness than pure alumina and good high-temperature stability. By combining these oxides, possibly with a weaker high-temperature oxide as the cell-boundary phase, it should be possible to product a strong, resilient FM that exhibits graceful failure. Several material combinations have been examined. Results on FM fabrication and microstructural development are presented

  16. Plutonium oxide shipment report

    International Nuclear Information System (INIS)

    1979-01-01

    While following procedures for unloading shipping containers containing plutonium oxide, SRP personnel experienced problems. While using a pipe cutter to cut through the wall of the inner container, the pipe section fell to the floor. Three empty food cans in the bottom of the inner canister also fell to the floor and a puff of smoke was observed. Personnel were evacuated and contamination was detected in the room. As a result of the investigations conducted by Westinghouse and SRP, thermal effects, food can coatings, and fuel volatiles were eliminated as the cause of the problem. Helium used to leak test the RL070 shipping container seals entered the inner canister through two weld defects resulting in a pressurization of the contents. When the end cap was removed, the inner canister vented rapidly, the food cans did not, thus creating a differential pressure across the food cans. This caused the food cans to swell. It was recommended that a dye penetrant test of all inner container welds be added. Additional unloading procedures were also recommended

  17. Nitric oxide nanoparticles

    Science.gov (United States)

    Schairer, David O.; Martinez, Luis R.; Blecher, Karin; Chouake, Jason S.; Nacharaju, Parimala; Gialanella, Philip; Friedman, Joel M.; Nosanchuk, Joshua D.; Friedman, Adam J.

    2012-01-01

    Nitric oxide (NO) is a critical component of host defense against invading pathogens; however, its therapeutic utility is limited due to a lack of practical delivery systems. Recently, a NO-releasing nanoparticulate platform (NO-np) was shown to have in vitro broad-spectrum antimicrobial activity and in vivo pre-clinical efficacy in a dermal abscess model. To extend these findings, both topical (TP) and intralesional (IL) NO-np administration was evaluated in a MRSA intramuscular murine abscess model and compared with vancomycin. All treatment arms accelerated abscess clearance clinically, histologically, and by microbiological assays on both days 4 and 7 following infection. However, abscesses treated with NO-np via either route demonstrated a more substantial, statistically significant decrease in bacterial survival based on colony forming unit assays and histologically revealed less inflammatory cell infiltration and preserved muscular architecture. These data suggest that the NO-np may be an effective addition to our armament for deep soft tissue infections. PMID:22286699

  18. Nitrous oxide availability.

    Science.gov (United States)

    Murray, M J; Murray, W J

    1980-04-01

    Nitrous oxide (N2O) is marketed as an inhalation anesthetic and as a food ingredient (e.g., whipping cream propellant). In the human, inhalation has been associated with "highs," peripheral nerve damage, mitotic poisoning of bone marrow, psychosis, and mental impairment. Exposure to hypoxemic mixtures has resulted in death. The commercial N2O sources specifically studied were aerosol whipping cream containers (three brands) and 6.5-cm cylinders, or chargers (two brands). The gas content and N2O concentrations of these devices were measured. The aerosol cans, when not shaken, will dispense at least 3 liters of 87 to 90% N2O. Charger misuse may occur when they are substituted for identically designed carbon dioxide (CO2) chargers of a seltzer bottle; 4.3 to 5.0 liters of 93 to 98% N2O is expelled at a controllable rate. The toxicity of these inexpensive N2O products, their high potential for misuse, and the absence of labeling (chargers) argue that their distribution be discontinued.

  19. Oxidative desulfurization: kinetic modelling.

    Science.gov (United States)

    Dhir, S; Uppaluri, R; Purkait, M K

    2009-01-30

    Increasing environmental legislations coupled with enhanced production of petroleum products demand, the deployment of novel technologies to remove organic sulfur efficiently. This work represents the kinetic modeling of ODS using H(2)O(2) over tungsten-containing layered double hydroxide (LDH) using the experimental data provided by Hulea et al. [V. Hulea, A.L. Maciuca, F. Fajula, E. Dumitriu, Catalytic oxidation of thiophenes and thioethers with hydrogen peroxide in the presence of W-containing layered double hydroxides, Appl. Catal. A: Gen. 313 (2) (2006) 200-207]. The kinetic modeling approach in this work initially targets the scope of the generation of a superstructure of micro-kinetic reaction schemes and models assuming Langmuir-Hinshelwood (LH) and Eley-Rideal (ER) mechanisms. Subsequently, the screening and selection of above models is initially based on profile-based elimination of incompetent schemes followed by non-linear regression search performed using the Levenberg-Marquardt algorithm (LMA) for the chosen models. The above analysis inferred that Eley-Rideal mechanism describes the kinetic behavior of ODS process using tungsten-containing LDH, with adsorption of reactant and intermediate product only taking place on the catalyst surface. Finally, an economic index is presented that scopes the economic aspects of the novel catalytic technology with the parameters obtained during regression analysis to conclude that the cost factor for the catalyst is 0.0062-0.04759 US $ per barrel.

  20. Oxidative desulfurization: Kinetic modelling

    International Nuclear Information System (INIS)

    Dhir, S.; Uppaluri, R.; Purkait, M.K.

    2009-01-01

    Increasing environmental legislations coupled with enhanced production of petroleum products demand, the deployment of novel technologies to remove organic sulfur efficiently. This work represents the kinetic modeling of ODS using H 2 O 2 over tungsten-containing layered double hydroxide (LDH) using the experimental data provided by Hulea et al. [V. Hulea, A.L. Maciuca, F. Fajula, E. Dumitriu, Catalytic oxidation of thiophenes and thioethers with hydrogen peroxide in the presence of W-containing layered double hydroxides, Appl. Catal. A: Gen. 313 (2) (2006) 200-207]. The kinetic modeling approach in this work initially targets the scope of the generation of a superstructure of micro-kinetic reaction schemes and models assuming Langmuir-Hinshelwood (LH) and Eley-Rideal (ER) mechanisms. Subsequently, the screening and selection of above models is initially based on profile-based elimination of incompetent schemes followed by non-linear regression search performed using the Levenberg-Marquardt algorithm (LMA) for the chosen models. The above analysis inferred that Eley-Rideal mechanism describes the kinetic behavior of ODS process using tungsten-containing LDH, with adsorption of reactant and intermediate product only taking place on the catalyst surface. Finally, an economic index is presented that scopes the economic aspects of the novel catalytic technology with the parameters obtained during regression analysis to conclude that the cost factor for the catalyst is 0.0062-0.04759 US $ per barrel

  1. Electrochromism in transition metal oxides

    International Nuclear Information System (INIS)

    Estrada, W.

    1993-01-01

    Electrochromism is discussed for transition metal oxides. Particularly tungsten oxide and nickel oxide are reviewed, in order to put forth the different aspects of the field. Since this phenomena has been reviewed by several authors, it is not tried to be comprehensive but rather pedagogical. The basic requirements for a material -in both non-emissive displays and energy efficiency applications- to be electrochromic, a general view of electrochromic mechanism, anodic and cathodic electrochromic materials, and current problems for a electrochromic theory are presented. (author) 45 refs., 8 figs

  2. Obesity, reproduction and oxidative stress

    Directory of Open Access Journals (Sweden)

    Tamara V. Zhuk

    2017-12-01

    Full Text Available The prevalence of obesity and overweight is one of the most pressing problems nowadays. Obesity as a comorbid condition affects all body systems. Obesity has been reported to be a risk factor not only for cardiovascular diseases and oncopathology, but also for fertility problems, many obstetric and perinatal complications worsening the maternal and infant health. The balance between the oxidative and antioxidant system is one of the indicators of the state of human homeostasis. Today it is proved that obesity is associated with an increase in oxidative stress and a decrease in antioxidant protection. This review reveals a close relationship between obesity, oxidative stress and reproductive problems.

  3. Chaperones, but not oxidized proteins, are ubiquitinated after oxidative stress

    DEFF Research Database (Denmark)

    Kästle, Marc; Reeg, Sandra; Rogowska-Wrzesinska, Adelina

    2012-01-01

    of these proteins by MALDI tandem mass spectrometry (MALDI MS/MS). As a result we obtained 24 different proteins which can be categorized into the following groups: chaperones, energy metabolism, cytoskeleton/intermediate filaments, and protein translation/ribosome biogenesis. The special set of identified......, ubiquitinated proteins confirm the thesis that ubiquitination upon oxidative stress is no random process to degrade the mass of oxidized proteins, but concerns a special group of functional proteins....

  4. Oxidation of tritium by hopcalite bed

    Energy Technology Data Exchange (ETDEWEB)

    Nishikawa, Masabumi; Shinnai, Kohsuke; Matsunaga, Sohichi; Kinoshita, Yoshihiko

    1984-08-01

    Oxidation by the catalyst bed with a metal oxide and subsequent adsorption to the porous dehydrative reagents is supposed to be effective process for scavenging tritium from an inert atmosphere. Use of spongy copper oxide or wires of copper oxide is not recommended to use as the metal oxide catalyst from the view point of mass transfer because of sintering and of limited effective surface area. Use of hopcalites and copper oxide-kieselguhr are examined in this study and it is concluded that hopcalites are more suitable as the metal oxide catalyst because they not only remain the oxidation power on hydrogen isotopes even at an ambient temperature, but also show a negligible drop in oxidation performances with repeated regeneration. The effective temperature is about 400/sup 0/C for hopcalites and 300-600/sup 0/C for copper oxide-kieselguhr to use as the oxidation bed of tritium.

  5. Oxidation of tritium by hopcalite bed

    International Nuclear Information System (INIS)

    Nishikawa, Masabumi; Shinnai, Kohsuke; Matsunaga, Sohichi; Kinoshita, Yoshihiko

    1984-01-01

    Oxidation by the catalyst bed with a metal oxide and subsequent adsorption to the porous dehydrative reagents is supposed to be effective process for scavenging tritium from an inert atmosphere. Use of spongy copper oxide or wires of copper oxide is not recommended to use as the metal oxide catalyst from the view point of mass transfer because of sintering and of limited effective surface area. Use of hopcalites and copper oxide-kieselguhr are examined in this study and it is concluded that hopcalites are more suitable as the metal oxide catalyst because they not only remain the oxidation power on hydrogen isotopes even at an ambient temperature, but also show a negligible drop in oxidation performances with repeated regeneration. The effective temperature is about 400 0 C for hopcalites and 300--600 0 C for copper oxide-kieselguhr to use as the oxidation bed of tritium. (author)

  6. Synthesis of vertically aligned metal oxide nanostructures

    KAUST Repository

    Roqan, Iman S.

    2016-03-03

    Metal oxide nanostructure and methods of making metal oxide nanostructures are provided. The metal oxide nanostructures can be 1 -dimensional nanostructures such as nanowires, nanofibers, or nanotubes. The metal oxide nanostructures can be doped or undoped metal oxides. The metal oxide nanostructures can be deposited onto a variety of substrates. The deposition can be performed without high pressures and without the need for seed catalysts on the substrate. The deposition can be performed by laser ablation of a target including a metal oxide and, optionally, a dopant. In some embodiments zinc oxide nanostructures are deposited onto a substrate by pulsed laser deposition of a zinc oxide target using an excimer laser emitting UV radiation. The zinc oxide nanostructure can be doped with a rare earth metal such as gadolinium. The metal oxide nanostructures can be used in many devices including light-emitting diodes and solar cells.

  7. Investigations performed on the compost worm Eisenia fetida and selected species of earthworms concerning the intake of HCB and pyrene with the goal of deriving a bioaccumulation test; Untersuchungen zur Aufnahme von HCB und Pyren durch den Kompostwurm Eisenia fetida und ausgewaehlte Regenwurmwildarten. Ableitung eines Bioakkumulationstests

    Energy Technology Data Exchange (ETDEWEB)

    Vespermann, A.; Riepert, F.; Pflugmacher, J. [Biologische Bundesanstalt fuer Land- und Forstwirtschaft, Inst. fuer Oekotoxikologie im Pflanzenschutz, Berlin (Germany)

    2003-07-01

    . Die Expositionszeit der Regenwuermer betrug 4 Wochen bei woechentlicher Bestimmung der Konzentrationen der Testsubstanzen in den Wuermern und Boeden. Die fuer E. fetida sowie die Wildarten errechneten Anreicherungsfaktoren (AF) beliefen sich bei HCB in Abhaengigkeit des verwendeten Bodens auf Werte zwischen 10 und 17 und bei Pyren auf Werte zwischen 0,9 und 1,7. Durch Umrechnung der Bodenkonzentrationen auf Gehalte in der Wasserphase und Ableitung der entsprechenden Anreicherungsfaktoren kann ein Vergleich mit BCF-Werten, die aus QSAR'S anderer Regenwurmarten und Fischen berechnet wurden, hergestellt werden. Die Ergebnisse lassen den Schluss zu, dass der Regenwurmtest mit E. fetida (OECD 1984, ISO 1998) fuer die Untersuchung der Bioakkumulation geeignet ist. (orig.)

  8. Contactless detection of the structure and selected parameters of a two-phase-flow by pattern recognition based ultrasonic techniques. Final report; Beruehrungslose Detektion der Struktur und Messung ausgewaehlter Parameter von Zweiphasenstroemungen durch Mustererkennungsverfahren unter Verwendung von Ultraschall als Messsonde. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Prasser, H.M.; Schuetz, P.; Kossok, N.

    1997-11-01

    , wenn die thermodynamischen und geometrischen Randbedingungen nahezu konstant bleiben. Durch die Erweiterung der Trainingsmatrizen um einen, die thermodynamischen Eigenschaften determinierenden Parameter (z.B. Temperatur, Druck) kann das Klassifizierungsverfahren auch auf Faelle mit veraenderlichen Stoffwerten angewandt werden. Das Mustererkennungsverfahren und die Ultraschalltechnik wurden experimentell optimiert und erprobt. Die Ultraschallsignale wurden ausserdem mit Hilfe der Methode des unueberwachten Lernens klassifiziert. Die gefundenen Gruppen von Signalmustern weisen eine deutliche Aehnlichkeit zu bekannten Stroemungskarten auf. Es wird gezeigt, dass das Verfahren des unueberwachten Lernens sich fuer die objektive Aufstellung von Stroemungskarten eignet. In einem speziellen Kapitel werden die Ergebnisse von Tests zur Fuellstandsmessung in einem Segment der Hauptumwaelzleitung von Druckwasserreaktoren vorgestellt. (orig.)

  9. MR-Imaging optimisation of the articular hip cartilage by using a T{sub 1}-weighted 3-dimensional gradient-echo sequence and the application of a hip joint traction; Magnetresonanztomographische Optimierung der Hueftknorpeldarstellung durch die Wahl einer T{sub 1}-Volumen-Gradienten-Echo-Sequenz und die Anwendung einer Hueftgelenkstraktion

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, R. [Heidelberg Univ. (Germany). Orthopaedische Klinik und Poliklinik; Bernd, L. [Heidelberg Univ. (Germany). Orthopaedische Klinik und Poliklinik; Wrazidlo, W. [ATOS-Praxisklinik, Heidelberg (Germany). Radiologische Gemeinschaftspraxis Drs. Lederer, Schneider und Wrazidlo; Lederer, W. [ATOS-Praxisklinik, Heidelberg (Germany). Radiologische Gemeinschaftspraxis Drs. Lederer, Schneider und Wrazidlo; Schneider, S. [ATOS-Praxisklinik, Heidelberg (Germany). Radiologische Gemeinschaftspraxis Drs. Lederer, Schneider und Wrazidlo

    1995-10-01

    Images of three animal cadaver hips, 8 dissected patient femoral heads and 18 hip joints of human corpses, all either with arthrosis stage I-III or artificial cartilage defects, were compared with their corresponding anatomic sections. Additional histomorphologic examinations of the arthrotic cartilages were conducted, and MR-Imaging of 20 healthy and 21 arthrotic patient hips was performed using a specific traction method. Using a T{sub 1}-weighted 3-dimensional gradient-echo sequence and a traction of the hip joint, it was possible due to the low-signal imaging of the joint space to separate in vivo the high-signal femoral head cartilage from the high-signal acetabular cartilage. In horizontal position of the phase-encoding parameter, minimisation of the chemical-shift artifact, mainly in the ventro-lateral areas, was accomplished. MRI measurements of the articular cartilage widths showed significant correlations (p < 0.001) with the corresponding anatomic sections. At the same time the T{sub 1} 3-dimensional gradient-echo sequence of the lateral femoral head with r = 0.94 showed the lowest deviations of the measurements. It was possible with MR-Imaging to distinguish four cartilage qualities. (orig./MG) [Deutsch] Im experimentellen Teil der Studie wurden den MRT-Bildern von drei Kadavertierhueften, 8 resezierten Patientenhueftkoepfen und 18 Leichenhueftgelenken, an denen entweder artifizielle Knorpeldefekte gesetzt wurden oder die ein Koxarthrose-Stadium I-III aufwiesen, die korrespondierenden makroskopischen Kryomikrotomschnitte zugeordnet. Bei den Koxarthrosen erfolgten zusaetzliche histomorphologische Knorpeluntersuchungen. Im klinischen Teil der Studie wurden 20 gesunde und 21 arthrotische Probandenhueftgelenke mit einem speziellen Traktionsverfahren untersucht. Unter Anwendung einer T{sub 1}-Volumen-Gradienten-Echo-Sequenz und einer Traktion am zu untersuchenden Hueftgelenk konnte in vivo durch die signalarme Darstellung des Gelenkspaltes der

  10. CNS metabolism in high-risk drug abuse, German version. Insights gained from {sup 1}H- and {sup 31}P MRS and PET; ZNS-Stoffwechsel bei Missbrauch von Hochrisikodrogen. Erkenntnisse durch {sup 1}H- und {sup 31}P-MRS sowie PET

    Energy Technology Data Exchange (ETDEWEB)

    Bodea, S.V. [Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Universitaetsklinikum des Saarlandes, Homburg/Saar (Germany)

    2017-06-15

    Methamphetamin-, Kokain- und Heroinkonsumenten bis Maerz 2017 wurde ueber PubMed-Recherchen erforscht. Suchbegriffe wie ''methamphetamine'', ''cocaine'', ''heroin'', ''MR spectroscopy'', ''PET'' wurden benutzt. MRT- und PET-Verfahren sind unerlaessliche Werkzeuge bei der Erforschung der zerebralen Reaktionen auf illegale Drogen. Zukuenftige Durchbrueche werden voraussichtlich durch die Untersuchung neuer Neurotransmittersysteme in der PET sowie die Abbildung von Phosphor- und Kohlenstoffmetaboliten in der MRT erfolgen. (orig.)

  11. Study of nitric oxide catalytic oxidation on manganese oxides-loaded activated carbon at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    You, Fu-Tian [Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); University of Chinese Academy of Sciences, Beijing (China); Yu, Guang-Wei, E-mail: gwyu@iue.ac.cn [Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); Wang, Yin, E-mail: yinwang@iue.ac.cn [Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); Xing, Zhen-Jiao [Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); Liu, Xue-Jiao; Li, Jie [Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); University of Chinese Academy of Sciences, Beijing (China)

    2017-08-15

    Highlights: • Loading manganese oxides on activated carbon effectively promotes NO oxidation. • NO adsorption-desorption on activated carbon is fundamental to NO oxidation. • A high Mn{sup 4+}/Mn{sup 3+} ratio contributes to NO oxidation by promoting lattice O transfer. - Abstract: Nitric oxide (NO) is an air pollutant that is difficult to remove at low concentration and low temperature. Manganese oxides (MnO{sub x})-loaded activated carbon (MLAC) was prepared by a co-precipitation method and studied as a new catalyst for NO oxidation at low temperature. Characterization of MLAC included X-ray diffraction (XRD), scanning electron microscopy (SEM), N{sub 2} adsorption/desorption and X-ray photoelectron spectroscopy (XPS). Activity tests demonstrated the influence of the amount of MnO{sub x} and the test conditions on the reaction. MLAC with 7.5 wt.% MnO{sub x} (MLAC003) exhibits the highest NO conversion (38.7%) at 1000 ppm NO, 20 vol.% O{sub 2}, room temperature and GHSV ca. 16000 h{sup −1}. The NO conversion of MLAC003 was elevated by 26% compared with that of activated carbon. The results of the MLAC003 activity test under different test conditions demonstrated that NO conversion is also influenced by inlet NO concentration, inlet O{sub 2} concentration, reaction temperature and GHSV. The NO adsorption-desorption process in micropores of activated carbon is fundamental to NO oxidation, which can be controlled by pore structure and reaction temperature. The activity elevation caused by MnO{sub x} loading is assumed to be related to Mn{sup 4+}/Mn{sup 3+} ratio. Finally, a mechanism of NO catalytic oxidation on MLAC based on NO adsorption-desorption and MnO{sub x} lattice O transfer is proposed.

  12. Phenol oxidation with hydrogen peroxide

    Energy Technology Data Exchange (ETDEWEB)

    Ramiez Cortina, R.C.; Hernadez Perez, I. [Univ. Autonoma Metropolitana - Azcapotzalco, Div. de CBI, Dept. de Energia, Azcapotzalco (Mexico); Ortiz Lozoya, C.E. [Univ. Autonoma Metropolitana - Azcapotzalco, Div. de CBI, Dept. de Energia, Azcapotzalco (Mexico)]|[Inst. Mexicano del Petroleo (Mexico); Alonso Gutierrez, M.S. [Inst. National Polytechnique, ENSCT, Lab. of Chimie Agro-Industrielle, Toulouse (France)

    2003-07-01

    In this work the process application of advanced oxidation is investigated with hydrogen peroxide, for the phenol destruction. The experiments were carried out in a glass reactor of 750 mL. Three phenol concentrations were studied (2000, 1000 and 500 ppm) being oxidized with H{sub 2}O{sub 2} (1, 2 and 3 M). The tests of oxidation had a reaction time of 48 h at ambient temperature and pressure. The phenol degradation was determined as COD at different reaction times and intermediate oxidation products were analyzed by chromatography. The results of this study show that it is possible to degrade phenol (1000 ppm) until 90% with H{sub 2}O{sub 2} 2M. Being achieved the best efficiency with a good molar relationship of H{sub 2}O{sub 2}/phenol. Intends a reaction outline in the degradation of the phenol. (orig.)

  13. Diffusion of single oxidation pond

    Directory of Open Access Journals (Sweden)

    Song Ruo-Yuan

    2016-01-01

    Full Text Available The hydraulic characteristic of an oxidation pond was studied by the tracer experiment, and an empirical formula of Peclet number was obtained, which can be well applied to the model of plug flow reactor with longitudinal diffusion.

  14. ENGINEERING BULLETIN: SUPERCRITICAL WATER OXIDATION

    Science.gov (United States)

    This engineering bulletin presents a description and status of supercritical water oxidation technology, a summary of recent performance tests, and the current applicability of this emerging technology. This information is provided to assist remedial project managers, contractors...

  15. Reduction of blue tungsten oxide

    International Nuclear Information System (INIS)

    Wilken, T.; Wert, C.; Woodhouse, J.; Morcom, W.

    1975-01-01

    A significant portion of commercial tungsten is produced by hydrogen reduction of oxides. Although several modes of reduction are possible, hydrogen reduction is used where high purity tungsten is required and where the addition of other elements or compounds is desired for modification of the metal, as is done for filaments in the lamp industry. Although several investigations of the reduction of oxides have been reported (1 to 5), few principles have been developed which can aid in assessment of current commercial practice. The reduction process was examined under conditions approximating commercial practice. The specific objectives were to determine the effects of dopants, of water vapor in the reducing atmosphere, and of reduction temperature upon: (1) the rate of the reaction by which blue tungsten oxide is reduced to tungsten metal, (2) the intermediate oxides associated with reduction, and (3) the morphology of the resulting tungsten powder

  16. Oxidation dynamics of aluminum nanorods

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ying [Argonne Leadership Computing Facility, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya [Collaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Chemical Engineering and Materials Science, Department of Computer Science, University of Southern California, Los Angeles, California 90089-0242 (United States)

    2015-02-23

    Aluminum nanorods (Al-NRs) are promising fuels for pyrotechnics due to the high contact areas with oxidizers, but their oxidation mechanisms are largely unknown. Here, reactive molecular dynamics simulations are performed to study thermally initiated burning of oxide-coated Al-NRs with different diameters (D = 26, 36, and 46 nm) in oxygen environment. We found that thinner Al-NRs burn faster due to the larger surface-to-volume ratio. The reaction initiates with the dissolution of the alumina shell into the molten Al core to generate heat. This is followed by the incorporation of environmental oxygen atoms into the resulting Al-rich shell, thereby accelerating the heat release. These results reveal an unexpectedly active role of the alumina shell as a “nanoreactor” for oxidation.

  17. Aliphatic amine oxides as ligands

    International Nuclear Information System (INIS)

    Garla, L.C.; Betarello, V.H.; Chiericato Junior, G.; De Giovani, W.F.

    1984-01-01

    The reaction between some hydrated lanthanide perchlorates with trimethylamine oxide (TMAO) was studied. Compounds of general formula Ln(Cl 4 ) 3 : . 5,5 TMAO (Ln = La, Pr, Er and Y) were isolated. (Author) [pt

  18. Electrolytic recovery of uranium oxides

    International Nuclear Information System (INIS)

    Gurr, W.R.

    1979-01-01

    A method is described for extracting uranium oxide from a solution of one or more uranium compounds, e.g. leach liquors, comprising subjecting the solution to electrolysis utilizing a high current density, e.g. 500 to 4000 amp/m 2 , whereby uranium oxide is formed at the cathode and is recovered. The method is particularly suited to a continuous process using a rotating cathode cell. (author)

  19. ASSESSMENT OF GALLIUM OXIDE TECHNOLOGY

    Science.gov (United States)

    2017-08-01

    AFRL-RY-WP-TR-2017-0167 ASSESSMENT OF GALLIUM OXIDE TECHNOLOGY Burhan Bayraktaroglu Devices for Sensing Branch Aerospace...TITLE AND SUBTITLE ASSESSMENT OF GALLIUM OXIDE TECHNOLOGY 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER N/A 6...report summarizes the current status of the Ga2O3 technology based on published results on theoretical electronic structure, materials growth, and

  20. Oxygen potentials of transuranium oxides

    International Nuclear Information System (INIS)

    Haruyoshi Otobe; Mituso Akabori; Arai Yasuo; Kazuo Minato

    2008-01-01

    The oxygen potentials of pyrochlore-type Pu 2 Zr 2 O 7+y , fluorite-type (Pu 0.5 Zr 0.5 )O 2-x and AmO 2-x have been measured by the electromotive force (EMF) method with a zirconia solid-electrolyte. The oxygen potentials of these oxides were reviewed. The phase relations, microstructure, equilibrium state of these oxides were discussed, referring to the isothermal curve of the oxygen potentials. (authors)

  1. Neutron diffraction and oxide research

    International Nuclear Information System (INIS)

    Hunter, B.; Howard, C.J.; Kennedy, B.J.

    1999-01-01

    Oxide compounds form a large class of interesting materials that have a diverse range of mechanical and electronic properties. This diversity and its commercial implications has had a significant impact on physics research. This is particularly evident in the fields of superconductivity magnetoresistivity and ferroelectricity, where discoveries in the last 15 years have given rise to significant shifts in research activities. Historically, oxides have been studied for many years, but it is only recently that significant effort has been diverted to the study of oxide materials for their application to mechanical and electronic devices. An important property of such materials is the atomic structure, for the determination of which diffraction techniques are ideally suited. Recent examples of structure determinations using neutron diffraction in oxide based systems are high temperature superconductors, where oxygen defects are a key factor. Here, neutron diffraction played a major role in determining the effect of oxygen on the superconducting properties. Similarly, neutron diffraction has enjoyed much success in the determination of the structures of the manganate based colossal magnetoresistive (CMR) materials. In both these cases the structure plays a pivotal role in determining theoretical models of the electronic properties. The neutron scattering group at ANSTO has investigated several oxide systems using neutron powder diffraction. Two such systems are presented in this paper; the zirconia-based materials that are used as engineering materials, and the perovskite-based oxides that include the well known cuprate superconductors and the manganate CMR materials

  2. Accelerated oxidation processes is biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Canakci, M.; Monyem, A.; Van Gerpen, J.

    1999-12-01

    Biodiesel is an alternative fuel for diesel engines that can be produced from renewable feedstocks such as vegetable oil and animal fats. These feedstocks are reacted with an alcohol to produce alkyl monoesters that can be used in conventional diesel engines with little or no modification. Biodiesel, especially if produced from highly unsaturated oils, oxidizes more rapidly than diesel fuel. This article reports the results of experiments to track the chemical and physical changes that occur in biodiesel as it oxidizes. These results show the impact of time, oxygen flow rate, temperature, metals, and feedstock type on the rate of oxidation. Blending with diesel fuel and the addition of antioxidants are explored also. The data indicate that without antioxidants, biodiesel will oxidize very quickly at temperatures typical of diesel engines. This oxidation results in increases in peroxide value, acid value, and viscosity. While the peroxide value generally reaches a plateau of about 350 meq/kg ester, the acid value and viscosity increase monotonically as oxidation proceeds.

  3. 46 CFR 154.1725 - Ethylene oxide.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Ethylene oxide. 154.1725 Section 154.1725 Shipping COAST....1725 Ethylene oxide. (a) A vessel carrying ethylene oxide must: (1) Have cargo piping, vent piping, and... space of an ethylene oxide cargo tank for a period of 30 days under the condition of paragraph (e) of...

  4. 49 CFR 172.426 - OXIDIZER label.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false OXIDIZER label. 172.426 Section 172.426... SECURITY PLANS Labeling § 172.426 OXIDIZER label. (a) Except for size and color, the OXIDIZER label must be... OXIDIZER label must be yellow. [Amdt. 172-123, 56 FR 66257, Dec. 20, 1991] ...

  5. 21 CFR 73.2250 - Iron oxides.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Iron oxides. 73.2250 Section 73.2250 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2250 Iron oxides. (a) Identity. The color additives iron oxides consist of any one or any combination of synthetically prepared iron oxides, including the...

  6. Solid oxide electrolyser cell

    Energy Technology Data Exchange (ETDEWEB)

    Hoejgaard Jensen, S.

    2006-12-15

    Solid oxide fuel cells (SOFCs) produced at Riso National Laboratory was tested as steam electrolysers under various current densities, operating temperatures and steam partial pressures. At 950 deg. C and a cell voltage of 1.48V the current density was -3.6 A/cm{sup 2} with app. 30% H{sub 2} + 70% H{sub 2}O in the inlet gas and a H{sub 2}O utilization of app. 40%. The tested SOECs were also used for CO{sub 2} electrolysis. Economy studies of CO and H2 production show that especially H{sub 2} production can be competitive in areas with cheap electricity. Assuming the above described initial performance and a lifetime of 10 years it is possible to achieve a production price of 0.7 US dollar/kg H{sub 2} with an electricity price of 1.3 US cent/kWh. The cell voltage was measured as function of time. In test of about two month of duration a long-term degradation was observed. At 850 deg. C, -0.5 A/cm{sup 2} with 50 vol% H{sub 2} the degradation rate was app. 20 mV/1000h. It was shown that the degradation happens at Ni/YSZ-electrode. The long term degradation is probably caused by coarsening of the Ni-particles. After onset of electrolysis operation a transient passivation/reactivation phenomena with duration of several days was observed. It was shown that the phenomenon is attributed to the SiO{sub 2} contamination at the Ni/YSZ electrode-electrolyte interface. The SiO{sub 2} arises from the albite glass sealing (NaAlSi{sub 3}O{sub 8}) that surrounds the electrode. Si may enter the Ni/YSZ electrode via the reaction Si(OH){sub 4}(g) {r_reversible} SiO{sub 2}(l)+H{sub 2}O(g). At the active sites of the Ni/YSZ electrode steam is reduced via the reaction H{sub 2}O - 2e {yields} H{sub 2}+O{sup 2-} . This shifts the equilibrium of the first reaction to form SiO{sub 2}(l) at the active sites. After a certain time the sealing crystallizes and the SiO{sub 2}(l) evaporates from the active sites and the cell reactivates. The passivation is shown to relate to a build up of a

  7. Oxidative stress-mediated antibacterial activity of graphene oxide and reduced graphene oxide in Pseudomonas aeruginosa

    OpenAIRE

    Gurunathan, Sangiliyandi; Han,Jae Woong; Abdal Daye,Ahmed; Eppakayala,Vasuki; Kim,Jin-Hoi

    2012-01-01

    Sangiliyandi Gurunathan, Jae Woong Han, Ahmed Abdal Dayem, Vasuki Eppakayala, Jin-Hoi KimDepartment of Animal Biotechnology, Konkuk University, Seoul, South KoreaBackground: Graphene holds great promise for potential use in next-generation electronic and photonic devices due to its unique high carrier mobility, good optical transparency, large surface area, and biocompatibility. The aim of this study was to investigate the antibacterial effects of graphene oxide (GO) and reduced graphene oxid...

  8. Protein oxidation in muscle foods: A review

    DEFF Research Database (Denmark)

    Lund, Marianne; Heinonen, Marina; Baron, Caroline P.

    2011-01-01

    insight into the reactions involved in the oxidative modifications undergone by muscle proteins. Moreover, a variety of products derived from oxidized muscle proteins, including cross-links and carbonyls, have been identified. The impact of oxidation on protein functionality and on specific meat quality...... and consequences of Pox in muscle foods. The efficiency of different anti-oxidant strategies against the oxidation of muscle proteins is also reported.......Protein oxidation in living tissues is known to play an essential role in the pathogenesis of relevant degenerative diseases, whereas the occurrence and impact of protein oxidation (Pox) in food systems have been ignored for decades. Currently, the increasing interest among food scientists...

  9. Hydrogen sulfide oxidation without oxygen - oxidation products and pathways

    International Nuclear Information System (INIS)

    Fossing, H.

    1992-01-01

    Hydrogen sulfide oxidation was studied in anoxic marine sediments-both in undisturbed sediment cores and in sediment slurries. The turn over of hydrogen sulfide was followed using 35 S-radiolabeled hydrogen sulfide which was injected into the sediment. However, isotope exchange reactions between the reduced sulfur compounds, in particular between elemental sulfur and hydrogen sulfide, influenced on the specific radioactivity of these pools. It was, therefore, not possible to measure the turn over rates of the reduced sulfur pools by the radiotracer technique but merely to use the radioisotope to demonstrate some of the oxidation products. Thiosulfate was one important intermediate in the anoxic oxidation of hydrogen sulfide and was continuously turned over by reduction, oxidation and disproportionation. The author discusses the importance of isotope exchange and also presents the results from experiments in which both 35 S-radiolabeled elemental sulfur, radiolabeled hydrogen sulfide and radiolabeled thiosulfate were used to study the intermediates in the oxidative pathways of the sulfur cycle

  10. Size of oxide vacancies in fluorite and perovskite structured oxides

    DEFF Research Database (Denmark)

    Chatzichristodoulou, Christodoulos; Norby, Poul; Hendriksen, Peter Vang

    2015-01-01

    An analysis of the effective radii of vacancies and the stoichiometric expansion coefficient is performed on metal oxides with fluorite and perovskite structures. Using the hard sphere model with Shannon ion radii we find that the effective radius of the oxide vacancy in fluorites increases...... with increasing ion radius of the host cation and that it is significantly smaller than the radius of the oxide ion in all cases, from 37% smaller for HfO2 to 13 % smaller for ThO2. The perovskite structured LaGaO3 doped with Sr or Mg or both is analyzed in some detail. The results show that the effective radius...... of an oxide vacancy in doped LaGaO3 is only about 6 % smaller than the oxide ion. In spite of this the stoichiometric expansion coefficient (a kind of chemical expansion coefficient) of the similar perovskite, LaCrO3, is significantly smaller than the stoichiometric expansion coefficient of the fluorite...

  11. Diffusion of hydrogen in iron oxides

    International Nuclear Information System (INIS)

    Bruzzoni, P.

    1993-01-01

    The diffusion of hydrogen in transitions metals oxides has been recently studied at room temperature through the permeability electrochemical technique. This work studies thin oxide layers grown in air or in presence of oxidizing atmospheres at temperatures up to 200 deg C. The substrate was pure iron with different superficial treatments. It was observed that these oxides reduce up to three magnitudes orders, the hydrogen stationary flux through membranes of usual thickness in comparison with iron membranes free of oxide. (Author)

  12. Transparent conducting oxides and production thereof

    Science.gov (United States)

    Gessert, Timothy A.; Yoshida, Yuki; Coutts, Timothy J.

    2014-06-10

    Transparent conducting oxides and production thereof are disclosed. An exemplary method of producing a transparent conducting oxide (TCO) material may comprise: providing a TCO target doped with either a high-permittivity oxide or a low-permittivity oxide in a process chamber. The method may also comprise depositing a metal oxide on the target in the process chamber to form a thin film having enhanced optical properties without substantially decreasing electrical quality.

  13. 21 CFR 186.1374 - Iron oxides.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Iron oxides. 186.1374 Section 186.1374 Food and... Substances Affirmed as GRAS § 186.1374 Iron oxides. (a) Iron oxides (oxides of iron, CAS Reg. No. 1332-37-2) are undefined mixtures of iron (II) oxide (CAS Reg. No. 1345-25-1, black cubic crystals) and iron (III...

  14. Wet-cupping removes oxidants and decreases oxidative stress.

    Science.gov (United States)

    Tagil, Suleyman Murat; Celik, Huseyin Tugrul; Ciftci, Sefa; Kazanci, Fatmanur Hacievliyagil; Arslan, Muzeyyen; Erdamar, Nazan; Kesik, Yunus; Erdamar, Husamettin; Dane, Senol

    2014-12-01

    Wet-cupping therapy is one of the oldest known medical techniques. Although it is widely used in various conditions such as acute\\chronic inflammation, infectious diseases, and immune system disorders, its mechanism of action is not fully known. In this study, we investigated the oxidative status as the first step to elucidate possible mechanisms of action of wet cupping. Wet cupping therapy is implemented to 31 healthy volunteers. Venous blood samples and Wet cupping blood samples were taken concurrently. Serum nitricoxide, malondialdehyde levels and activity of superoxide dismutase and myeloperoxidase were measured spectrophotometrically. Wet cupping blood had higher activity of myeloperoxidase, lower activity of superoxide dismutase, higher levels of malondialdehyde and nitricoxide compared to the venous blood. Wet cupping removes oxidants and decreases oxidative stress. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Metal oxide nanorod arrays on monolithic substrates

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Pu-Xian; Guo, Yanbing; Ren, Zheng

    2018-01-02

    A metal oxide nanorod array structure according to embodiments disclosed herein includes a monolithic substrate having a surface and multiple channels, an interface layer bonded to the surface of the substrate, and a metal oxide nanorod array coupled to the substrate surface via the interface layer. The metal oxide can include ceria, zinc oxide, tin oxide, alumina, zirconia, cobalt oxide, and gallium oxide. The substrate can include a glass substrate, a plastic substrate, a silicon substrate, a ceramic monolith, and a stainless steel monolith. The ceramic can include cordierite, alumina, tin oxide, and titania. The nanorod array structure can include a perovskite shell, such as a lanthanum-based transition metal oxide, or a metal oxide shell, such as ceria, zinc oxide, tin oxide, alumina, zirconia, cobalt oxide, and gallium oxide, or a coating of metal particles, such as platinum, gold, palladium, rhodium, and ruthenium, over each metal oxide nanorod. Structures can be bonded to the surface of a substrate and resist erosion if exposed to high velocity flow rates.

  16. Heterogeneous Partial (ammOxidation and Oxidative Dehydrogenation Catalysis on Mixed Metal Oxides

    Directory of Open Access Journals (Sweden)

    Jacques C. Védrine

    2016-01-01

    Full Text Available This paper presents an overview of heterogeneous partial (ammoxidation and oxidative dehydrogenation (ODH of hydrocarbons. The review has been voluntarily restricted to metal oxide-type catalysts, as the partial oxidation field is very broad and the number of catalysts is quite high. The main factors of solid catalysts for such reactions, designated by Grasselli as the “seven pillars”, and playing a determining role in catalytic properties, are considered to be, namely: isolation of active sites (known to be composed of ensembles of atoms, Me–O bond strength, crystalline structure, redox features, phase cooperation, multi-functionality and the nature of the surface oxygen species. Other important features and physical and chemical properties of solid catalysts, more or less related to the seven pillars, are also emphasized, including reaction sensitivity to metal oxide structure, epitaxial contact between an active phase and a second phase or its support, synergy effect between several phases, acid-base aspects, electron transfer ability, catalyst preparation and activation and reaction atmospheres, etc. Some examples are presented to illustrate the importance of these key factors. They include light alkanes (C1–C4 oxidation, ethane oxidation to ethylene and acetic acid on MoVTe(SbNb-O and Nb doped NiO, propene oxidation to acrolein on BiMoCoFe-O systems, propane (ammoxidation to (acrylonitrile acrylic acid on MoVTe(SbNb-O mixed oxides, butane oxidation to maleic anhydride on VPO: (VO2P2O7-based catalyst, and isobutyric acid ODH to methacrylic acid on Fe hydroxyl phosphates. It is shown that active sites are composed of ensembles of atoms whose size and chemical composition depend on the reactants to be transformed (their chemical and size features and the reaction mechanism, often of Mars and van Krevelen type. An important aspect is the fact that surface composition and surface crystalline structure vary with reaction on stream until

  17. Solid oxide electrochemical reactor science.

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Neal P. (Colorado School of Mines, Golden, CO); Stechel, Ellen Beth; Moyer, Connor J. (Colorado School of Mines, Golden, CO); Ambrosini, Andrea; Key, Robert J. (Colorado School of Mines, Golden, CO)

    2010-09-01

    Solid-oxide electrochemical cells are an exciting new technology. Development of solid-oxide cells (SOCs) has advanced considerable in recent years and continues to progress rapidly. This thesis studies several aspects of SOCs and contributes useful information to their continued development. This LDRD involved a collaboration between Sandia and the Colorado School of Mines (CSM) ins solid-oxide electrochemical reactors targeted at solid oxide electrolyzer cells (SOEC), which are the reverse of solid-oxide fuel cells (SOFC). SOECs complement Sandia's efforts in thermochemical production of alternative fuels. An SOEC technology would co-electrolyze carbon dioxide (CO{sub 2}) with steam at temperatures around 800 C to form synthesis gas (H{sub 2} and CO), which forms the building blocks for a petrochemical substitutes that can be used to power vehicles or in distributed energy platforms. The effort described here concentrates on research concerning catalytic chemistry, charge-transfer chemistry, and optimal cell-architecture. technical scope included computational modeling, materials development, and experimental evaluation. The project engaged the Colorado Fuel Cell Center at CSM through the support of a graduate student (Connor Moyer) at CSM and his advisors (Profs. Robert Kee and Neal Sullivan) in collaboration with Sandia.

  18. Cost reduction through combined solutions?; Kostensenkung durch Kombinationsloesungen?

    Energy Technology Data Exchange (ETDEWEB)

    Bilitewski, B. [Technische Univ. Dresden (Germany). Inst. fuer Abfallwirtschaft und Altlasten

    1998-09-01

    The implementation of material-specific residue treatment processes requires reconstruction measures both in the case of mechanical-biological and in that of thermal treatment plants. Such measures involves great uncertainties and wide variation in cost prediction. The present paper deals with various factors that influence the costs of residual waste treatment. [Deutsch] Zur Umsetzung der stoffspezifischen Restabfallbehandlung sind Anpassungen sowohl der derzeit betriebenen mechanisch-biologischen als auch der thermischen Anlagen erforderlich, was zu Unsicherheiten und grossen Schwankungsbreiten bei den Kostenprognosen fuehrt. Der Bericht beleuchtet verschiedene Einflussgroessen auf die Kosten der Behandlung des Restabfalls. (orig./SR)

  19. Energy - achieving an optimum through information. Energie - optimal durch Information

    Energy Technology Data Exchange (ETDEWEB)

    Gitt, W.

    1986-01-01

    What have computer programs in common with everyday human behaviour. Or the birds' passage, or photosynthesis, or the chemical reactions in a cell. They all primarily are information-controlled processes. The book under review deals with 'information' and 'energy', two main concepts in today's technological world. 'Energy' during the last few years has become a significant criterion with regard to technological progress. 'Information' is not only a main term in informatics terminology, but also a central concept for example in biology, linguistics, and communication science. The author shows that every 'information' is the result of an intellectual and purposeful process. The concept of information is taken as the red thread leading the author's journey through manifold strata of modern life, asking questions, finding answers, discussing problems. The wide spectrum of aspects discussed, including for instance a new approach to the Bible, and the remarkable examples presented by the author, make this book a treasure of knowledge, and of faith.

  20. Energy transparency by business intelligence; Energietransparenz durch Business Intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Flieder, Karl [Academia Nova, Schwechat (Austria). Business Process Management and Engineering

    2012-10-15

    The efficiency of energy is one of several key performance parameters, when it comes to the questions how innovative and economical a plant operates compared to its competitors. However, in order to evaluate energy saving potentials in the industry, we need transparency first: A clear picture of the energy consumption based on products and processes. This transparency can be accomplished through business intelligence (BI). This term encompasses analytical processes and tools that can help to transform enterprise data and information into applied knowledge. In this article, we focus on transparency of the energy consumption through a targeted analysis by making use of business intelligence.

  1. Rechtsmissbrauch durch „AGG-Hopping“ / Steffen Krieger

    Index Scriptorium Estoniae

    Krieger, Steffen

    2016-01-01

    Euroopa Kohtu otsusest, mis puudutab töökohale kandideerija staatust eesmärgiga esitada kahju hüvitamise nõudeid kui teda ei valita tööle ja sellise teguviisi käsitlemist õiguse kuritarvitamisena. Vt. ka lk. 699-700

  2. Safety - thanks to the freedom to decide; Sicherheit durch Entscheidungsfreiheit

    Energy Technology Data Exchange (ETDEWEB)

    Brandes, B. [Brandes GmbH, Eutin (Germany)

    1994-12-01

    The pipe manufacturers who are grouped together in the EuHP have reached agreement on offering bare copper wire as `their` compatible standard sensor. This is not a new decision: This always was the case, and was always sold as such if the customer did not express any particular wishes of their own in this respect when placing the order. The inspiration for this action is, rather, concern with some monitoring systems. These have become the subject of gossip over the past few years, and we too view this development with concern. Only the `Nordic system` and the resistance comparison measuring system process are unaffected by this. Against this background, attempts are also being made to have copper declared as the sole standard. This decision is in fact only a logical defence of interests, because compatibility between not only the pipe manufacturers but also between the laying processes is only available with the resistance wire - and that has always been the case. It is important not to treat the topic as an `article of faith`, but in such a way that the way is open to solutions which really are acceptable to all parties. (orig./KO) [Deutsch] Die im EuHP zusammengefassten Rohrhersteller haben sich nun darauf verstaendigt, kuenftig zwei Kupferadern als `ihren` Standardsensor anzubieten. Das ist keine neue Entscheidung, denn das war schon immer so und wurde immer dann verkauft, wenn der Kunde keine feste eigene Meinung in die Auftragsvergabe einbrachte. Neu ist, dass man kuenftig `keine stoerenden Komponenten` in den Rohren mehr will und dass man das `Kupfersystem` offensiv nach aussen traegt. Mit diesem Hintergrund ist es verstaendlich, dass manche bei dieser Gelegenheit gleich den Sensor, der ihnen als Rohrhersteller am angenehmsten ist, zum Standard erklaeren moechten. Dieser Beschluss ist konsequente Interessenwahrnehmung. Denn: Wirkliche Kompatibilitaet nicht nur zwischen den Verlegeverfahren, gibt es mit dem Widerstandsdraht schon seit ueber 20 Jahren. Ob der Vorstoss mehr Vor- als Nachteile bringt, muessen daher die entscheiden, die als Auftraggeber Nutzen aus der Fernheizleitung und Sicherheit fuer das investierte Geld aus dem Sicherheitssystem ziehen wollen. Eine Fehlentscheidung waere endgueltig und kritisch fuer die Fernwaerme. (orig./KO)

  3. Asymmetrische Alkensynthesen durch Kinetische Racematspaltungen von Aldehyden mit Chiralen Phosphonaten

    DEFF Research Database (Denmark)

    Kreuder, Reinhard; Bodmann, Kerstin; von Zezschwitz, Paultheo

    1998-01-01

    The article gives an overview of how synthetically useful chiral building blocks can be obtained by kinetic resolution of chiral, racemic aldehydes through the reaction with chiral phosphonate reagents....

  4. Verletzung der A. subscapularis durch Reposition einer vorderen Schulterluxation

    DEFF Research Database (Denmark)

    Schmal, H; Strohm, P C; Rosahl, S K

    2006-01-01

    report a case with rupture of the arteria subscapularis following reduction of an anterior shoulder dislocation with formation of an axillary hematoma and consecutive paresis of the plexus brachialis. Interdisciplinary operative revision was necessary to remove the hematoma, stop the hemorrhage...... and for neurolysis of the plexus brachialis. Treatment resulted in a speedy recovery of the patient. Gentle reduction of a dislocated shoulder is a prerequisite for a low complication rate. Contrast-enhanced computed tomography facilitated diagnosis of the hematoma and identification of the bleeding vessel....

  5. Erfahrbares Programmieren durch den zielgerichten Einsatz von Flugdrohnen im Informatikunterricht

    Directory of Open Access Journals (Sweden)

    Raphael Zender

    2015-11-01

    Full Text Available Today, teaching on fundamental programming skills is one of the essential IT-related topics in schools. This trend is brought forward by simple development environments like Scratch. Those abstract from detailed programming concepts in terms of graphical building blocks. Exotic runtime platforms like robots further increase the attractiveness. The solution “ScratchDrone” provides quadrocopters as an innovative new platform to run Scratch programs. The modular system architecture of ScratchDrone allows children to program on multiple layers of abstraction depending on their individual learning progress. The combination of a multi-layer didactical model, the movement in 3D space, as well as the natural human fascination for flying results in a high learning motivation for young programmers.

  6. Qualitätssicherung an Hochschulen durch Zulassungsverfahren

    OpenAIRE

    Hell, Benedikt

    2007-01-01

    Dieser Beitrag zeigt auf, dass Zulassungsverfahren einen wichtigen Beitrag zur Qualitätssicherung im tertiären Bildungsbereich leisten können. In Form eines Gedankenspiels wird das Portersehe Value Chain Framework herangezogen, um die besondere Stellung von Auswahlverfahren als Qualitätssicherungselement aufzuzeigen. Einen weiteren Schwerpunkt bildet die Analyse der prognostischen Aussagekraft und der Betrachtung des Nutzens von Auswahlverfahren. Hierzu werden Kennzahlen präsentiert, die durc...

  7. Product bundling as a customer loyalty strategy; Kundenbindung durch Produktbuendel

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, H.G. [Arthur Andersen Business Consulting GmbH, Duesseldorf (Germany)

    2000-12-01

    In the deregulated market in electricity, all marketers and energy-related service providers are competing not only for new customers, but also for customer loyalty. The article sets out concepts and strategies developed by a business consulting firm, for maintaing or enhancing customer loyalty in the end-use market segment, focusing on customized product bundling. A four-tier approach for product bundle development and implementation is discussed. (orig./CB) [German] Fuer Energieversorger und -dienstleister ergibt sich neben der Neukundengewinnung der strategische Zwang zur Bindung bestehender Kunden. An praktischen Ansaetzen fuer Privatkunden stehen neben Value-Added-Services und Incentives (Kundenclub, -karte) nicht zuletzt Produktbuendel (Bundles) zur Verfuegung. Zur erfolgreichen Entwicklung und Implementierung von Produktbuendeln wird ein vierphasiges Vorgehensmodell erlaeutert. (orig./CB)

  8. Die Leben Einsteins eine Reise durch die Geschichte der Physik

    CERN Document Server

    Fiami

    2005-01-01

    Jeder kennt die Namen Einstein, Newton oder Galilei. aber was weiss man über sie? Hier ein Porträt Einsteins anhand von sechs Meilensteinen aus der Geschichte der Physik. Einstein tritt auf als Protagonist in verschiedenen Epochen und bei verschiedenen Entdeckungen, die die Welt verändert haben.

  9. Allergien durch Stiche und Bisse von Insekten und Spinnentieren

    DEFF Research Database (Denmark)

    Blank, S; Schiener, M; Ollert, M.

    2016-01-01

    Allergic reactions due to stings of Hymenoptera species, such as honeybees or yellow jackets, are well known as severe allergies with potentially fatal outcome. Much less common is that also bites of blood-sucking insects (mosquitos, horseflies, flies, bugs, lice and fleas) and arachnids (ticks...

  10. Verminderung der Prüfungsangst durch Modellernen im Klassenzimmer

    OpenAIRE

    Ellgring, Johann Heinrich; Elbing, Eberhard

    2010-01-01

    Die Wirksamkeit des Modellernens im Klassenzimmer zur Veränderung der Prüfungsangst wurde bei 152 Knaben und 164 Mädchen der Klassen 5-8 einer Hauptschule untersucht. Den Schülern wurden die Angst-Skalen (TASe und GASC) von Sarason vorgelegt. Anhand der Fragebogenergebnisse wurden die Kinder den Kategorien "hochängstlich" (HA), "mittelängstlich" (MA) und "niedrigängstlich" (NA) zugeordnet. Für 3,5 Monate wurden die folgenden Paarbildungen (Banknachbarn) beibehalten: HA neben HA, MA und NA, NA...

  11. Y{sub 2}BaCuO{sub 5} particle distribution in YBa{sub 2}Cu{sub 3}O{sub 7-y} grains of melt growth processed YBCO oxides; Y{sub 2}BaCuO{sub 5}-Partikelverteilung in YBa{sub 2}Cu{sub 3}O{sub 7-y}-Koernern durch das Melt-Growth-Verfahren verarbeiteter YBCO-Oxide

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chan-Joong; Park, Soon-Dong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of). Neutron Science Div.; Park, Hai-Woong [Korea Univ. of Technology and Education, Chungnam (Korea, Republic of). College of Energy, Materials and Chemical Engineering

    2013-02-01

    Y{sub 2}BaCuO{sub 5} (Y211) particle distribution within YBa{sub 2}Cu{sub 3}O{sub 7-y} (Y123) grains of YBCO samples melt growth (MG) processed was examined. To understand the processing variables on the Y211 distribution, a cooling rate (R{sub C}=1 K/h to R{sub C}=20 K/h) through a peritectic temperature (T{sub p} = 1010 C), a precursor powder size and composition were changed. Two different Y211 distributions (a linear x-like track and planar butterfly-like pattern) were observed, depending on the processing variables. The linear x-like Y211 tracks were observed in the Y123 samples prepared using a stoichiometric Y123 precursor, whereas the planar butterfly-like Y211 patterns were observed in the Y{sub 1.8}Ba{sub 2.4}Cu{sub 3.4}O{sub 7-d} (Y1.8) samples prepared using an Y211-excess composition precursor. The track and planar Y211 patterns were clearer at lower R{sub C} (slower growth rate of Y123 grains) and for the smaller Y211 particles. In contrast, the random Y211 distribution was dominant at the higher R{sub C} and for the larger Y211 particles. The Y211 distribution patterns in the Y123 grains were explained in terms of the interfacial energy difference among growing Y123 fronts. (orig.)

  12. Anaerobic sulfide-oxidation in marine colorless sulfur-oxidizing bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.; Nair, S.; Chandramohan, D.

    Colorless sulfur-oxidizing bacteria are ubiquitous in Indian waters and have the ability to oxidize sulfide under anaerobic conditions. These bacteria can not only mediate the sulfur cycle oxidatively but also the nitrogen cycle reductively without...

  13. Resveratrol and Endothelial Nitric Oxide

    Directory of Open Access Journals (Sweden)

    Ning Xia

    2014-10-01

    Full Text Available Nitric oxide (NO derived from the endothelial NO synthase (eNOS has antihypertensive, antithrombotic, anti-atherosclerotic and antiobesogenic properties. Resveratrol is a polyphenol phytoalexin with multiple cardiovascular and metabolic effects. Part of the beneficial effects of resveratrol are mediated by eNOS. Resveratrol stimulates NO production from eNOS by a number of mechanisms, including upregulation of eNOS expression, stimulation of eNOS enzymatic activity and reversal of eNOS uncoupling. In addition, by reducing oxidative stress, resveratrol prevents oxidative NO inactivation by superoxide thereby enhancing NO bioavailability. Molecular pathways underlying these effects of resveratrol involve SIRT1, AMPK, Nrf2 and estrogen receptors.

  14. Oxides gets environmentally-friendly

    DEFF Research Database (Denmark)

    Pryds, Nini

    for high temperature oxide thermoelectric (TE) modules to become a viable route for power generation, the overall efficiency of these devices must be improved. While most research currently focuses on the enhancement of the thermoelectric properties of the p- and n-type elements of the module, it is also...... necessary to demonstrate a working oxide module and develop stable interconnects with low contact resistance as well as mechanical and the chemical stability. In this presentation I will also show our latest results on the performance of oxide module made of ZnO doped Al (n-type) and CaCoO 349 (p-type) [1...... in realizing cooling devices with high efficiency and low global warming potentials, which are highly desirable for a broad range of applications. The technology relies on the magnetocaloric effect in a solid refrigerant rather than the temperature change that occurs when a gas is compressed. This talk...

  15. Atmospheric oxidation of selected hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Benter, T.; Olariu, R.I.

    2002-02-01

    This work presents investigations on the gas-phase chemistry of phenol and the cresol isomers performed in a 1080 l quartz glass reactor in Wuppertal and in a large-volume outdoor photoreactor EUPHORE in Valencia, Spain. The studies aimed at clarifying the oxidation mechanisms of the reactions of these compounds with OH and NO{sub 3} radicals. Product investigations on the oxidation of phenol and the cresol isomers initiated by OH radicals were performed in the 1080 l quartz glass reactor with analyses by in situ FT-IR absorption spectroscopy. The primary focus of the investigations was on the determination of product yields. This work represents the first determination and quantification of 1,2-dihydroxybenzenes in the OH oxidation of phenolic compounds. Possible reaction pathways leading to the observed products have been elucidated. (orig.)

  16. CELLULOSE DEGRADATION BY OXIDATIVE ENZYMES

    Directory of Open Access Journals (Sweden)

    Maria Dimarogona

    2012-09-01

    Full Text Available Enzymatic degradation of plant biomass has attracted intensive research interest for the production of economically viable biofuels. Here we present an overview of the recent findings on biocatalysts implicated in the oxidative cleavage of cellulose, including polysaccharide monooxygenases (PMOs or LPMOs which stands for lytic PMOs, cellobiose dehydrogenases (CDHs and members of carbohydrate-binding module family 33 (CBM33. PMOs, a novel class of enzymes previously termed GH61s, boost the efficiency of common cellulases resulting in increased hydrolysis yields while lowering the protein loading needed. They act on the crystalline part of cellulose by generating oxidized and non-oxidized chain ends. An external electron donor is required for boosting the activity of PMOs. We discuss recent findings concerning their mechanism of action and identify issues and questions to be addressed in the future.

  17. Oxidative stability of marine phospholipids

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng; Nielsen, Nina Skall; Baron, Caroline Pascale

    Many studies have shown that marine phospholipids (MPL) provide more advantages than fish oil. They have better bioavailability, better resistance towards oxidation and higher content of eicosapentaenoic acids (EPA) and docosahexaenoic acids (DHA) than oily triglycerides (fish oil). The objective...... of this study is to investigate the oxidative and hydrolytic stability of MPL. In addition, this study also investigates the effect of chemical composition of MPL and Maillard reaction (interaction between lipids oxidation products with the residue of amino acids) on MPL emulsions’ stability. Firstly, MPL were...... was further investigated through measurement of secondary volatile compounds by Solid Phase Microextraction at several time intervals. On the other hand, the Maillard reaction was investigated through the measurement of color changes and pyrrole content before and after 32 days storage. Preliminary result...

  18. Graphite oxidation in HTGR atmosphere

    International Nuclear Information System (INIS)

    Growcock, F.B.; Barry, J.J.; Finfrock, C.C.; Rivera, E.; Heiser, J.H. III

    1982-01-01

    On-going and recently completed studies of the effect of thermal oxidation on the structural integrity of HTGR candidate graphites are described, and some results are presented and discussed. This work includes the study of graphite properties which may play decisive roles in the graphites' resistance to oxidation and fracture: pore size distribution, specific surface area and impurity distribution. Studies of strength loss mechanisms in addition to normal oxidation are described. Emphasis is placed on investigations of the gas permeability of HTGR graphites and the surface burnoff phenomenon observed during recent density profile measurements. The recently completed studies of catalytic pitting and the effects of prestress and stress on reactivity and ultimate strength are also discussed

  19. Graphite Oxidation Thermodynamics/Reactions

    International Nuclear Information System (INIS)

    Propp, W.A.

    1998-01-01

    The vulnerability of graphite-matrix spent nuclear fuel to oxidation by the ambient atmosphere if the fuel canister is breached was evaluated. Thermochemical and kinetic data over the anticipated range of storage temperatures (200 to 400 C) were used to calculate the times required for a total carbon mass loss of 1 mgcm-2 from a fuel specimen. At 200 C, the time required to produce even this small loss is large, 900,000 yr. However, at 400 C the time required is only 1.9 yr. The rate of oxidation at 200 C is negligible, and the rate even at 400 C is so small as to be of no practical consequence. Therefore, oxidation of the spent nuclear fuel upon a loss of canister integrity is not anticipated to be a concern based upon the results of this study

  20. Adaptive oxide electronics: A review

    Science.gov (United States)

    Ha, Sieu D.; Ramanathan, Shriram

    2011-10-01

    Novel information processing techniques are being actively explored to overcome fundamental limitations associated with CMOS scaling. A new paradigm of adaptive electronic devices is emerging that may reshape the frontiers of electronics and enable new modalities. Creating systems that can learn and adapt to various inputs has generally been a complex algorithm problem in information science, albeit with wide-ranging and powerful applications from medical diagnosis to control systems. Recent work in oxide electronics suggests that it may be plausible to implement such systems at the device level, thereby drastically increasing computational density and power efficiency and expanding the potential for electronics beyond Boolean computation. Intriguing possibilities of adaptive electronics include fabrication of devices that mimic human brain functionality: the strengthening and weakening of synapses emulated by electrically, magnetically, thermally, or optically tunable properties of materials.In this review, we detail materials and device physics studies on functional metal oxides that may be utilized for adaptive electronics. It has been shown that properties, such as resistivity, polarization, and magnetization, of many oxides can be modified electrically in a non-volatile manner, suggesting that these materials respond to electrical stimulus similarly as a neural synapse. We discuss what device characteristics will likely be relevant for integration into adaptive platforms and then survey a variety of oxides with respect to these properties, such as, but not limited to, TaOx, SrTiO3, and Bi4-xLaxTi3O12. The physical mechanisms in each case are detailed and analyzed within the framework of adaptive electronics. We then review theoretically formulated and current experimentally realized adaptive devices with functional oxides, such as self-programmable logic and neuromorphic circuits. Finally, we speculate on what advances in materials physics and engineering may

  1. On hydrazine oxidation in nitric acid media

    International Nuclear Information System (INIS)

    Zil'berman, B.Ya.; Lelyuk, G.A.; Mashkin, A.N.; Yasnovitskaya, A.L.

    1988-01-01

    Yield of products of radiolytic ( 60 Co gamma radiation) and chemical hydrazine (HZ) oxidation in nitric acid media is studied. Under radiolyte HZ oxidation by nitric acid hydrazoic acid, ammonia and nitrogen appear to be the reaction products. HN 3 yield maximum under HZN oxidation makes up ∼ 0.35 mol per a mol of oxiduzed HZN. Under chemical oxidation HZN is oxidized by HNO 3 according to reaction catalysed by technetium HN 3 yield makes up ∼ 0.35 mol per a mol of oxidized HZN. Radiation-chemical oxidation of HN 3 proceeds up to its complete decomposition, decomposition rate is comparable with HZ oxidation rate. Under the chemical oxidation HN 3 is more stable, it is slowly decomposed after complete HZ decomposition

  2. Method for hot pressing beryllium oxide articles

    Science.gov (United States)

    Ballard, Ambrose H.; Godfrey, Jr., Thomas G.; Mowery, Erb H.

    1988-01-01

    The hot pressing of beryllium oxide powder into high density compacts with little or no density gradients is achieved by employing a homogeneous blend of beryllium oxide powder with a lithium oxide sintering agent. The lithium oxide sintering agent is uniformly dispersed throughout the beryllium oxide powder by mixing lithium hydroxide in an aqueous solution with beryllium oxide powder. The lithium hydroxide is converted in situ to lithium carbonate by contacting or flooding the beryllium oxide-lithium hydroxide blend with a stream of carbon dioxide. The lithium carbonate is converted to lithium oxide while remaining fixed to the beryllium oxide particles during the hot pressing step to assure uniform density throughout the compact.

  3. Dissolving method for nuclear fuel oxide

    International Nuclear Information System (INIS)

    Tomiyasu, Hiroshi; Kataoka, Makoto; Asano, Yuichiro; Hasegawa, Shin-ichi; Takashima, Yoichi; Ikeda, Yasuhisa.

    1996-01-01

    In a method of dissolving oxides of nuclear fuels in an aqueous acid solution, the oxides of the nuclear fuels are dissolved in a state where an oxidizing agent other than the acid is present together in the aqueous acid solution. If chlorate ions (ClO 3 - ) are present together in the aqueous acid solution, the chlorate ions act as a strong oxidizing agent and dissolve nuclear fuels such as UO 2 by oxidation. In addition, a Ce compound which generates Ce(IV) by oxidation is added to the aqueous acid solution, and an ozone (O 3 ) gas is blown thereto to dissolve the oxides of nuclear fuels. Further, the oxides of nuclear fuels are oxidized in a state where ClO 2 is present together in the aqueous acid solution to dissolve the oxides of nuclear fuels. Since oxides of the nuclear fuels are dissolved in a state where the oxidizing agent is present together as described above, the oxides of nuclear fuels can be dissolved even at a room temperature, thereby enabling to use a material such as polytetrafluoroethylene and to dissolve the oxides of nuclear fuels at a reduced cost for dissolution. (T.M.)

  4. Oxidation phase growth diagram of vanadium oxides film fabricated by rapid thermal annealing

    Institute of Scientific and Technical Information of China (English)

    Tamura KOZO; Zheng-cao LI; Yu-quan WANG; Jie NI; Yin HU; Zheng-jun ZHANG

    2009-01-01

    Thermal evaporation deposited vanadium oxide films were annealed in air by rapid thermal annealing (RTP). By adjusting the annealing temperature and time, a series of vanadium oxide films with various oxidation phases and surface morphologies were fabricated, and an oxidation phase growth diagram was established. It was observed that different oxidation phases appear at a limited and continuous annealing condition range, and the morphologic changes are related to the oxidation process.

  5. RESIDUAL RISK ASSESSMENT: ETHYLENE OXIDE ...

    Science.gov (United States)

    This document describes the residual risk assessment for the Ethylene Oxide Commercial Sterilization source category. For stationary sources, section 112 (f) of the Clean Air Act requires EPA to assess risks to human health and the environment following implementation of technology-based control standards. If these technology-based control standards do not provide an ample margin of safety, then EPA is required to promulgate addtional standards. This document describes the methodology and results of the residual risk assessment performed for the Ethylene Oxide Commercial Sterilization source category. The results of this analyiss will assist EPA in determining whether a residual risk rule for this source category is appropriate.

  6. Oxidation of amines by flavoproteins.

    Science.gov (United States)

    Fitzpatrick, Paul F

    2010-01-01

    Many flavoproteins catalyze the oxidation of primary and secondary amines, with the transfer of a hydride equivalent from a carbon-nitrogen bond to the flavin cofactor. Most of these amine oxidases can be classified into two structural families, the D-amino acid oxidase/sarcosine oxidase family and the monoamine oxidase family. This review discusses the present understanding of the mechanisms of amine and amino acid oxidation by flavoproteins, focusing on these two structural families. Copyright 2009 Elsevier Inc. All rights reserved.

  7. Aromatic-radical oxidation chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Glassman, I.; Brezinsky, K. [Princeton Univ., NJ (United States)

    1993-12-01

    The research effort has focussed on discovering an explanation for the anomalously high CO{sub 2} concentrations observed early in the reaction sequence of the oxidation of cyclopentadiene. To explain this observation, a number of plausible mechanisms have been developed which now await experimental verification. One experimental technique for verifying mechanisms is to probe the reacting system by perturbing the radical concentrations. Two forms of chemical perturbation of the oxidation of cyclopentadiene were begun during this past year--the addition of NO{sub 2} and CO to the reacting mixture.

  8. Supported versus colloidal zinc oxide for advanced oxidation processes

    Science.gov (United States)

    Laxman, Karthik; Al Rashdi, Manal; Al Sabahi, Jamal; Al Abri, Mohammed; Dutta, Joydeep

    2017-07-01

    Photocatalysis is a green technology which typically utilizes either supported or colloidal catalysts for the mineralization of aqueous organic contaminants. Catalyst surface area and surface energy are the primary factors determining its efficiency, but correlation between the two is still unclear. This work explores their relation and hierarchy in a photocatalytic process involving both supported and colloidal catalysts. In order to do this the active surface areas of supported zinc oxide nanorods (ZnO NR's) and colloidal zinc oxide nanoparticles (having different surface energies) were equalized and their phenol oxidation mechanism and capacity was analyzed. It was observed that while surface energy had subtle effects on the oxidation rate of the catalysts, the degradation efficiency was primarily a function of the surface area; which makes it a better parameter for comparison when studying different catalyst forms of the same material. Thus we build a case for the use of supported catalysts, wherein their catalytic efficiency was tested to be unaltered over several days under both natural and artificial light, suggesting their viability for practical applications.

  9. Graphene oxide and H2 production from bioelectrochemical graphite oxidation.

    Science.gov (United States)

    Lu, Lu; Zeng, Cuiping; Wang, Luda; Yin, Xiaobo; Jin, Song; Lu, Anhuai; Jason Ren, Zhiyong

    2015-11-17

    Graphene oxide (GO) is an emerging material for energy and environmental applications, but it has been primarily produced using chemical processes involving high energy consumption and hazardous chemicals. In this study, we reported a new bioelectrochemical method to produce GO from graphite under ambient conditions without chemical amendments, value-added organic compounds and high rate H2 were also produced. Compared with abiotic electrochemical electrolysis control, the microbial assisted graphite oxidation produced high rate of graphite oxide and graphene oxide (BEGO) sheets, CO2, and current at lower applied voltage. The resultant electrons are transferred to a biocathode, where H2 and organic compounds are produced by microbial reduction of protons and CO2, respectively, a process known as microbial electrosynthesis (MES). Pseudomonas is the dominant population on the anode, while abundant anaerobic solvent-producing bacteria Clostridium carboxidivorans is likely responsible for electrosynthesis on the cathode. Oxygen production through water electrolysis was not detected on the anode due to the presence of facultative and aerobic bacteria as O2 sinkers. This new method provides a sustainable route for producing graphene materials and renewable H2 at low cost, and it may stimulate a new area of research in MES.

  10. Protective effect of nitric oxide against arsenic-induced oxidative ...

    African Journals Online (AJOL)

    The effects of NO on alleviating arsenic-induced oxidative damage in tall fescue leaves were investigated. Arsenic (25 M) treatment induced significantly accumulation of reactive oxygen species (ROS) and led to serious lipid peroxidation in tall fescue leaves and the application of 100 M SNP before arsenic stress resulted ...

  11. Oxidation of aniline with strong and weak oxidants

    Czech Academy of Sciences Publication Activity Database

    Sapurina, I. Yu.; Stejskal, Jaroslav

    2012-01-01

    Roč. 82, č. 2 (2012), s. 256-275 ISSN 1070-3632 R&D Projects: GA AV ČR IAA400500905 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyaniline * conducting polymer * oxidant Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.432, year: 2012

  12. SELECTIVE OXIDATION IN SUPERCRITICAL CARBON DIOXIDE USING CLEAN OXIDANTS

    Science.gov (United States)

    We have systematically investigated heterogeneous catalytic oxidation of different substrates in supercritical carbon dioxide (SC-CO2). Three types of catagysts: a metal complex, 0.5% platinum g-alumina and 0.5% palladium g-alumina were used at a pressure of 200 bar, temperatures...

  13. Oxidation kinetics of Si and SiGe by dry rapid thermal oxidation, in-situ steam generation oxidation and dry furnace oxidation

    Science.gov (United States)

    Rozé, Fabien; Gourhant, Olivier; Blanquet, Elisabeth; Bertin, François; Juhel, Marc; Abbate, Francesco; Pribat, Clément; Duru, Romain

    2017-06-01

    The fabrication of ultrathin compressively strained SiGe-On-Insulator layers by the condensation technique is likely a key milestone towards low-power and high performances FD-SOI logic devices. However, the SiGe condensation technique still requires challenges to be solved for an optimized use in an industrial environment. SiGe oxidation kinetics, upon which the condensation technique is founded, has still not reached a consensus in spite of various studies which gave insights into the matter. This paper aims to bridge the gaps between these studies by covering various oxidation processes relevant to today's technological needs with a new and quantitative analysis methodology. We thus address oxidation kinetics of SiGe with three Ge concentrations (0%, 10%, and 30%) by means of dry rapid thermal oxidation, in-situ steam generation oxidation, and dry furnace oxidation. Oxide thicknesses in the 50 Å to 150 Å range grown with oxidation temperatures between 850 and 1100 °C were targeted. The present work shows first that for all investigated processes, oxidation follows a parabolic regime even for thin oxides, which indicates a diffusion-limited oxidation regime. We also observe that, for all investigated processes, the SiGe oxidation rate is systematically higher than that of Si. The amplitude of the variation of oxidation kinetics of SiGe with respect to Si is found to be strongly dependent on the process type. Second, a new quantitative analysis methodology of oxidation kinetics is introduced. This methodology allows us to highlight the dependence of oxidation kinetics on the Ge concentration at the oxidation interface, which is modulated by the pile-up mechanism. Our results show that the oxidation rate increases with the Ge concentration at the oxidation interface.

  14. New insight of high temperature oxidation on self-exfoliation capability of graphene oxide

    Science.gov (United States)

    Liu, Yuhang; Zeng, Jie; Han, Di; Wu, Kai; Yu, Bowen; Chai, Songgang; Chen, Feng; Fu, Qiang

    2018-05-01

    The preparation of graphene oxide (GO) via Hummers method is usually divided into two steps: low temperature oxidation at 35 °C (step I oxidation) and high temperature oxidation at 98 °C (step II oxidation). However, the effects of these two steps on the exfoliation capability and chemical structure of graphite oxide remain unclear. In this study, both the functional group content of graphite oxide and the entire evolution of interlayer spacing were investigated during the two steps. Step I oxidation is a slowly inhomogeneous oxidation step to remove unoxidized graphite flakes. The prepared graphite oxide can be easily self-exfoliated but contains a lot of organic sulfur. During the first 20 min of step II oxidation, the majority of organic sulfur can be efficiently removed and graphite oxide still remains a good exfoliation capability due to sharp increasing of carboxyl groups. However, with a longer oxidation time at step II oxidation, the decrease of organic sulfur content is slowed down apparently but without any carboxyl groups forming, then graphite oxide finally loses self-exfoliation capability. It is concluded that a short time of step II oxidation can produce purer and ultralarge GO sheets via self-exfoliation. The pure GO is possessed with better thermal stability and liquid crystal behavior. Besides, reduced GO films prepared from step II oxidation show better mechanical and electric properties after reducing compared with that obtained only via step I oxidation.

  15. [Solidification of volatile oil with graphene oxide].

    Science.gov (United States)

    Yan, Hong-Mei; Jia, Xiao-Bin; Zhang, Zhen-Hai; Sun, E; Xu, Yi-Hao

    2015-02-01

    To evaluate the properties of solidifying volatile oil with graphene oxide, clove oil and zedoary turmeric oil were solidified by graphene oxide. The amount of graphene oxide was optimized with the eugenol yield and curcumol yield as criteria. Curing powder was characterized by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The effects of graphene oxide on dissolution in vitro and thermal stability of active components were studied. The optimum solidification ratio of graphene oxide to volatile oil was 1:1. Dissolution rate of active components had rare influence while their thermal stability improved after volatile oil was solidified. Solidifying herbal volatile oil with graphene oxide deserves further study.

  16. Thermal Oxidation of Structured Silicon Dioxide

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lehrmann; Hansen, Ole; Jensen, Jørgen Arendt

    2014-01-01

    The topography of thermally oxidized, structured silicon dioxide is investigated through simulations, atomic force microscopy, and a proposed analytical model. A 357 nm thick oxide is structured by removing regions of the oxide in a masked etch with either reactive ion etching or hydrofluoric acid....... Subsequent thermal oxidation is performed in both dry and wet ambients in the temperature range 950◦C to 1100◦C growing a 205 ± 12 nm thick oxide in the etched mask windows. Lifting of the original oxide near the edge of the mask in the range 6 nm to 37 nm is seen with increased lifting for increasing...

  17. Calibration of partial safety factors for wind turbine rotor blades against fatigue; Kalibrering af partielle sikkerhedsfaktorer for udmattelse af vindmoellerotorer. Bilagsrapport

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, C.J.; Ronold, K.O.; Thoegersen, M.L.

    2000-08-01

    The report describes a calibration of partial safety factors for wind turbine rotor blades subjected to fatigue loading in flapwise and edgewise bending. While earlier models - developed by the authors - dealt with such calibrations for site-specific individual turbines only, the calibration model applied herein covers an integrated analysis with different turbines on different sites and with different blade materials. The result is an optimized set of partial safety factors, i.e. a set of safety factors that lead to minimum deviation from the target reliability of the achieved reliabilities over the selected scope of turbines, sites and materials. The turbines included in the study cover rated powers of 450-600 kW. (au)

  18. Calibration of partial safety factors for wind turbine rotor blades against fatigue failure; Kalibrering af partielle sikkerhedsfaktorer for udmattelse af vindmoellerotorer

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, C.J.; Ronold, K.O.; Thoegersen, M.L.

    2000-08-01

    The report describes a calibration of partial safety factors for wind turbine rotor blades subjected to fatigue loading in flapwise and edgewise bending. While earlier models - developed by the authors - dealt with such calibrations for site-specific individual turbines only, the calibration model applied herein covers an integrated analysis with different turbines on different sites and with different blade materials. The result is an optimized set of partial safety factors, i.e. a set of safety factors that lead to minimum deviation from the target reliability of the achieved reliabilities over the selected scope of turbines, sites and materials. The turbines included in the study cover rated powers of 450-600 kW. The result from the calibration are discussed in relation to the partial safety factors that are given in the Danish codes for design of glass fibre reinforced rotor blades (DS472 and DS456). (au)

  19. Plasmas pour valorisation totale ou partielle des gaz contenant de l'H2S Plasmas for Total Or Partial Upgrading of H2s Containing Gases

    Directory of Open Access Journals (Sweden)

    Czernichowski A.

    2006-12-01

    Full Text Available Des procédés par plasmas alternatifs au procédé Claus sont proposés pour produire de l'hydrogène et récupérer du soufre à partir des gaz contenant une forte teneur en H2S. Quand la teneur en H2S est moins importante, des techniques plasma peuvent également être utiles pour assister certains étages du procédé classique Claus ou réaliser ce procédé pour des gaz non conventionnels. Les tests allant jusqu'à l'échelle industrielle sont menés dans divers réacteurs à plasmas et les résultats encourageants rapportés de la littérature et de la recherche propre laissent envisager des prochaines applications. Plasma assisted processes are proposed to act as an alternative to the Claus process in order to recover hydrogen and sulphur from high H2S gases. For less concentrated gases plasma techniques may also be inserted into classical Claus plant or may allow treatment of non conventional gases. Up to industrial scale tests are performed using different plasma reactors. The literature-based results as well as our own ones make the future applications quite optimistic.

  20. The partial privatization of EDF and the fight against the greenhouse effect; Privatisation partielle d'EDF et lutte contre l'effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    Prevot, H

    2006-01-15

    Despite competition, the rationale of the marketplace will push the price of electricity far above the costs of electricity produced by nuclear power. The fight against the greenhouse effect will then suffer a serious setback because even an old fossil-fueled power plant will stay profitable. In order to reduce the emission of greenhouse gases, it will not be enough to optimize the contribution of nuclear energy in the panel of power production means, it will also necessary to make fossil energies more expensive through taxes or any other penalizing constraints. The government will have to channel competition.

  1. Le tourisme pyrénéen face au développement durable : une intégration partielle et hésitante

    Directory of Open Access Journals (Sweden)

    Sylvie Clarimont

    2009-12-01

    Full Text Available L’étude transfrontalière comparée des formes et des résultats de la mise en œuvre du tourisme durable par l’intercommunalité dans les Pyrénées occidentales montre les difficultés du modèle à s’imposer ; pire, il est souvent l’alibi justifiant une multitude de politiques touristiques éclatées, qui, par défaut de prospective et de cohérence territoriale, rendent difficile son application. Une recherche a été menée sur ce thème de 2004 à 2006 à l’Université de Pau et des Pays de l’Adour en collaboration avec l’Université de Saragosse. Elle est parvenue à trois conclusions dont on présente ici l’essentiel : 1. l’intégration du tourisme dans le champ du développement durable a été tardive et hésitante, d’où un retard important dans son application ; 2. en France plus qu’en Espagne, le « millefeuille » des intercommunalités et l’absence de transfert du tourisme en bloc de compétences ont produit un éclatement de l’ancrage territorial de l’aménagement et de sa gestion, occultant la prise en compte du long terme dans les projets ; 3. la prégnance toujours sensible des grandes opérations d’immobilier de loisirs bouleverse les équilibres résidentiels et fonciers traditionnels et témoigne d’un effort de planification insuffisant.The cross-border comparative study of the forms and outcomes of the introduction of sustainable tourism by inter-communal efforts in the western Pyrenees has revealed the difficulties of imposing the model, and, worse, this model is often the alibi justifying a mass of incoherent tourist policy, which, being defective in forward planning and territorial coherence, makes it difficult to apply. Research on this theme was carried out from 2004-2006 at the Université de Pau et des Pays de l'Adour in collaboration with the University of Saragosse. The three conclusions it reached are presented in summarized form as follows: 1 - incorporation of tourism in the field of sustainable development has been belated and hesitant, resulting in big delays as far as its application is concerned; 2 - in France more than in Spain, the multi-level nature of inter-communal bodies together with the lack of transfer of competences in mass tourism have produced the breaking-up of territorial-based development and its management, excluding long-term consideration project-wise. 3 - the overbearing presence of big leisure-construction operations is upturning the traditional residential and land management balance and reveals insufficient initial planning efforts.

  2. Partial combustion of a fuel cartridge in reactor G1; Combustion partielle d'une cartouche de combustible dans le reacteur G 1

    Energy Technology Data Exchange (ETDEWEB)

    De, Rouville; Leduc,; Segot, [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    On the 26 october 1956, after having stopped a few days, the G1 reactor was started up again. The burst slug system gave a first warning at 19 h 07 on loading side, a second one at 19 h 13 on unloading side, and so on others. Ath 15 the Control Engineer ordered a quick decrease of power and then, made it rise again from 2 to 5 MW, to find out, with accuracy, the failing channel. Soon after, in order to avoid any exterior contamination, scanning had to be stopped and a {gamma} ray detecting system outside the burst slug piping system, found out the damaged element in the channel 19-13. The health stations recording showed that the highest experienced measures were still notably lower than the maxima permissible levels. The methodical examination and the unloading of the damaged channel lasted three weeks. On the loading side, bare uranium billets could be seen on a magnesia powder bed. On the unloading side, the can was undamaged, but the element's end was hanging inside the gap of the inlet air. Pushed back, about 30 cm (12 in.), on the loading side, the element got blocked up. After several tests, while argon was still being injected, working staff being kept under strict protection conditions, a countersink tube was operating like the one used for drilling. The channel was cleaned up by sucking up, without, however, avoiding slight contamination in the building of the reactor. On the 7 december 1956, the reactor had a divergence at 2 MW, the first since the fault. A hundred or so channels were still giving a background, therefore making the burst slug system inefficient for those channels. Systematical brushing and sucking up were not able to reduce it beyond a certain level. It forced the reactor to operate during several months with 56 unloaded semi-channels. At last, in june 1957, two handling allowed the reactor to operate in a satisfactory way: removal of 1 mm-thickness of graphite, by re-reaming 54 semi-channels and setting on the burst slug detection-devices, some null regulating tension systems, annealing the background due to continuous pollution. This event has been fruitful. A grid trap has been set right ahead the reactor. Stricter instructions have been given for rising power operations and automatic burst slug sy (already improved as said above) has been duplicated by a human control. At last, the fault has pointed out that the reactors with gap had the disadvantage of facilitating the contamination of channels from one to another. On the other hand, graphite stores the radioactive dusts and hinders an easy decontamination. (author) [French] Le 26 octobre 1956, le reacteur G1 etait remis en marche apres un arret de quelques jours. L'installation de detection de rupture de gaines donna un premier signal de prealerte a 19h07 cote chargement, un second a 19h13 cote dechargement, puis d'autres. Le chef de quart ordonna a 19h15 une baisse rapide de la puissance mais voulant reperer le canal fautif avec precision la fit remonter ensuite a 2 puis a 5 MW. Bientot, par crainte de contamination exterieure, on dut arreter l'exploration et c'est par detection {gamma} a l'exterieur des tuyaux de detection de rupture de gaine qu'on identifia la cartouche endommagee dans le canal 19-13. Les enregistrements des stations de sante montrerent que les pointes observees etaient restees notablement inferieures aux limites maxima admissibles. L'examen methodique et le degagement du canal accidente occuperent trois semaines. On put apercevoir cote chargement les billettes d'uranium nues sur un lit de poudre de magnesie; cote dechargement, la gaine etait intacte mais l'extremite de la cartouche 'pendait' a l'interieur de la fente d'arrivee d'air. Repoussee cote chargement d'environ 30 cm, la cartouche se bloqua. Apres des essais divers, toujours sous injection d'argon, et avec des protections severes du personnel, on mit en oeuvre un tube fraise, analogue a ceux utilises pour les forages. On nettoya le canal par aspiration, sans toutefois eviter de legeres contaminations du hall de la pile. Le 7 decembre 1956 eut lieu une premiere divergence a 2 MW. Une centaine de canaux donnaient encore un bruit de fond rendant inoperante pour ces canaux la detection de ruptures de gaines. Des brossages et aspirations systematiques ne purent le reduire ala d'un palier qui obligea a faire fonctionner le reacteur pendant plusieurs mois avec 56 demi-canaux decharges. Enfin, en juin 1957, deux operations rendirent au reacteur un regime pleinement satisfaisant; enlevement d'une epaisseur de 1 mm de graphite par realesage de 54 demi-canaux et montage sur les appareils de detection de dispositifs d'opposition de tension reglable eliminant dans les mesures la part du bruit de fond due a la pollution permanente. Cet incident a ete riche d'enseignements: une grille piege a ete mise en place juste en amont de la pile; les consignes de montee en puissance ont ete rendues plus prudentes, le controle automatique des detections de ruptures de gaines (deja ameliorees comme il a ete dit) a ete double d'un controle humain. Enfin, l'incident a mis en evidence que les piles a fente avaient le defaut de faciliter la contamination des canaux de proche en proche. Par ailleurs le graphite emmagasine les poussieres radioactives et rend la decontamination difficile. (auteur)

  3. Concept Mapping zur Unterstützung der differentialdiagnostischen Hypothesenbildung im fallbasierten Online-Lernsystem CASUS: Qualitative Verbesserung der Diagnosefindung durch ICD-10 Kodierung [Concept mapping for supporting the differential diagnostic generation of hypotheses in the case-based online learning system CASUS: Qualitative improvement of dagnostic performance through ICD-10 coding

    Directory of Open Access Journals (Sweden)

    Kernt, Marcus

    2008-08-01

    akzeptiert werden und zu einer vermehrten Hypothesenbildung beitragen. Es gibt bisher jedoch wenige Erkenntnisse über die Qualität der dabei vom Anwender erstellten Hypothesen. Die vorliegende Studie untersucht die Qualität der im Netzwerk-Tool im fallbasierten Lernsystem CASUS erstellten Hypothesen und inwieweit diese durch Kodierung mittels ICD10 präzisiert werden können. Methodik: Die Lernenden bearbeiteten zu zweit einen Computerlernfall zum Thema Malaria. Wir randomisierten 192 Teilnehmer der Studie aus dem 3. Studienjahr an der Universität München in zwei Gruppen: Gruppe A wurde gebeten, die erdachten Hypothesen vor der Eingabe in das Netzwerk-Tool mittels eines ICD10-Browsers zu kodieren. Gruppe B erstellte ihre Hypothesen ohne weitere Hilfsmittel. Die Netzwerke wurden quantitativ und qualitativ evaluiert und die Ergebnisse der beiden Gruppen verglichen. Als Referenz diente das von Experten erstellte Netzwerk. Ergebnisse: 87 differentialdiagnostische Netzwerke konnten ausgewertet werden. In Gruppe A mit ICD10-Kodierung der Hypothesen, konnten die Lernenden signifikant häufiger (p<0,005 die exakte Hauptdiagnose Malaria tropica stellen. In der Gruppe ohne ICD10 Kodierung wurde signifikant häufiger (p<0,005 die unpräzise Diagnose "Malaria" gestellt. Für die Nebendiagnosen ergaben sich qualitativ und quantitativ keine Unterschiede. Schlussfolgerungen: Die ICD10-Kodierung der Hypothesen im Netzwerk-Tool führte zu einer präziseren Diagnosestellung der Studierenden im klinischen Studienabschnitt. Die Integration eines ICD-Browsers zur Unterstützung der differentialdiagnostischen Hypothesenbildung in fallbasierten Lernsystemen ist sinnvoll.

  4. Reduzierbarkeit der Abbrecherquote im Humanmedizinstudium durch das Hamburger Auswahlverfahren für Medizinische Studiengänge - Naturwissenschaftsteil (HAM-Nat [Possible reduction of the medical school dropout number by the Hamburg Assessment test for Medicine - part Natural sciences (HAM-Nat

    Directory of Open Access Journals (Sweden)

    Harendza, Sigrid

    2008-05-01

    eines zukünftigen „guten Arztes“ zu entwickeln und zu validieren. Daher beschränkt sich das Auswahlverfahren in Hamburg auf das pragmatische Ziel die Studienabbrecherzahl zu reduzieren, damit möglichst viele Studienanfänger durch gute Lehre zu „guten Ärzten“ ausgebildet werden. Methodik: Zu diesem Zweck wurde der HAM-Nat (Hamburger Auswahlverfahren für Medizinische Studiengänge - Naturwissenschaftsteil mit 52 Multiple-choice Fragen auf Schulniveau über naturwissenschaftliche Kenntnisse und ihre Anwendung entwickelt, zunächst an 6 Schulen in 3 Bundesländern erprobt und dann mit 333 Studienanfängern im Oktober 2006 durchgeführt. Das Testergebnis und die Abiturnote wurden mit dem Studienerfolg in den ersten beiden Semestern korreliert. Als Studienerfolgsparameter wurde die Anzahl der bestandenen Leistungsnachweise verwendet. Ergebnisse: Das HAM-Nat-Ergebnis korreliert nach dem 2. Semester höher mit dem Studienerfolg als die Abiturnote, von der es relativ unabhängig ist. Insbesonders zeigt die Simulation eines Auswahlverfahrens unter Berücksichtigung von HAM-Nat-Ergebnis und Abiturnote eine deutliche Reduktion der Zahl der Studienabbrecher im Vergleich zur jetzigen Auswahl nur nach Abiturnote. Weitere abgefragte mögliche Studienauswahlparameter wie belegte naturwissenschaftliche Kurse oder eine abgeschlossene Berufsausbildung korrelieren nicht mit besserem Studienerfolg. Schlussfolgerung: Der HAM-Nat ist ein wertvolles zusätzliches Auswahlverfahren für Studienbewerber in der Medizin. Aufgrund dieser Ergebnisse hat die Medizinische Fakultät Hamburg beschlossen, den HAM-Nat für die Studienbewerberauswahl zum Wintersemester 2008/2009 einzuführen.

  5. The semidry acid-anhydrite process (the use of flue gas desulphurization (FGD) gypsum by development of a new process for the production of FGD anhydrite); Das quasitrockene Saeure-Anhydrit-Verfahren (Erweiterung der Verwendungsmoeglichkeiten von REA-Gips durch Entwicklung eines Verfahrens zur Herstellung von REA-Anhydrit aus REA-Gips)

    Energy Technology Data Exchange (ETDEWEB)

    Wirsching, F. [Gebr. Knauf, Westdeutsche Gipswerke, Iphofen (Germany); Hueller, R. [Gebr. Knauf, Westdeutsche Gipswerke, Iphofen (Germany); Limmer, B. [Gebr. Knauf, Westdeutsche Gipswerke, Iphofen (Germany)

    1994-10-01

    -Anhydrit untersucht. Die Reaktion erfolgt mit feuchtem, feinteiligem REA-Gips unter der katalytischen Wirkung kleiner Mengen Schwefelsaeure bei Temperaturen um 100 bis 200 C. Es wird wasserfreier REA-Anhydrit mit orthorhombischer Kristallstruktur erhalten. Die Umwandlung des Kristallgitters von Calciumsulfat-Dihydrat in Calciumsulfat-Anhydrit II vollzieht sich dabei direkt durch Mineralneubildung. Diese Umwandlung wird zu einem Verfahren entwickelt und als `Quasitrockenes Saeure-Anydrit-Verfahren` bezeichnet. Die Reaktion und ihr Mechanismus wurde zuerst in Laborversuchen untersucht. Als Ausgangsstoff ist jedes feinteilige Calciumsulfat-Dihydrat geeignet. Der bereits im Kraftwerk feinteilig-kristallin erzeugte REA-Gips mit 10% Restfeuchte ist besonders vorteilhaft, da er fuer diese Verwendung vorher nicht getrocknet und nicht gemahlen werden muss. Die Verfahrensentwicklung wurde bis in den halbtechnischen Massstab durchgefuehrt und Auslegungsgrundlagen fuer Grossanlagen an Kraftwerksstandorten erarbeitet. Als Reaktionsaggregat zeigte sich der direkt beheizte Drehrohrofen geeignet. Der REA-Anhydrit wird in diesem Verfahren als trockenes feinteiliges Produkt mit reproduzierbaren Teilchengroessen um 2 Mikron erhalten und besitzt neuartige technologische Eigenschaften. Seine Verwendungsmoeglichkeit wurde fuer die Zementindustrie sowie als Rohstoff zur Herstellung von Fuellstoffen untersucht. Fuer die Zementindustrie ist er grundsaetzlich geeignet. Der Einsatz als Fuellstoff ermoeglicht eine erweiterte Verwendung des REA-Gipses ausserhalb der traditionellen Bereiche der Gipsindustrie. Erste Versuche erlauben die Schlussfolgerung, dass der REA-Anhydrit nach einer Aufbereitung, die ebenfalls labormaessig neu entwickelt wurde, die fuer einen hochwertigen Fuellstoff notwendigen guten Eigenschaftsmerkmale hat. (orig.)

  6. MC-PELMO 3.0 - a computer model to estimate groundwater contamination caused by leaching of wood preservatives from storage sites of treated wood in Germany; Grundwassergefaehrdung durch Holzschutzmittel. MCPELMO 3.0 - ein mathematische Simulationsprogramm zur Abschaetzung der Grundwassergefaehrdung unter Holzlagerflaechen in Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Klein, M. [Fraunhofer-Inst. fuer Molekularbiologie und Angewandte Oekologie, Schmallenberg-Grafschaft (Germany); Herrmann, M. [Umweltbundesamt, Berlin (Germany)

    2004-07-01

    verarbeitet dabei 22 ausgewaehlte Versickerungsszenarien, die ihrerseits aus der Verknuepfung von Leitboeden aus 12 Bodenregionen und Wetterdaten von 9 Klimastationen abgeleitet wurden. Diese Szenarien werden gewichtet mit den Standortdaten von Holzimpraegnierbetrieben in Deutschland. Als Ergebnis der Simulationsrechnungen werden statistische Wahrscheinlichkeiten fuer die Konzentrationen im Sickerwasser unter Holzlagerplaetzen in den vom Anwender ausgewaehlten Regionen angegeben. Ergebnisse und Diskussion. Die Ergebnisprotokolle der Simulationsrechnungen beinhalten sowohl mittlere Sickerwasserkonzentrationen als auch frei waehlbare Perzentile (50-99), sowie die jeweils maximale Standortkonzentration. Die Ergebnisse koennen in Relation zur Gesamtflaeche der Bundesrepublik, den jeweiligen forstlich genutzten Flaechenanteilen, oder zur Dichte von Holzschutzmittel anwendenden Betrieben dargestellt werden. Neben der Konzentration der Ausgangssubstanz koennen auch fuer mehrere Abbauprodukte Konzentrationen in der Grundwasserneubildung berechnet werden. Schlussfolgerungen. Das beschriebene Modell ist insbesondere zum Vergleich der Grundwassergefaehrdung durch verschiedene Holzschutzmittel geeignet. Die vergleichende Bewertung stellt ein neues Element der EU-Politik zur Chemikaliensicherheit dar, das zum ersten Mal in der Biozidrichtlinie 98/8/EG festgeschrieben wurde. Die Ergebnisse der Modellrechnungen identifizieren aber auch besonders gefaehrdete Regionen in Deutschland, fuer die geeignete Risikominderungsmassnahmen ergriffen werden muessen um das dortige Grundwasser zu schuetzen. (orig.)

  7. Metal oxide/polyaniline nanocomposites

    Indian Academy of Sciences (India)

    Nanocomposites of iron oxide with conducting polymer in the form of powders of varying compositions have been studied to understand the effects of particle size, cluster size and magnetic inter-particle interactions. The sizes of the nanoparticles were estimated to be ∼ 10–20 nm from the X-ray diffraction (XRD) and the ...

  8. Ferroelectricity in undoped hafnium oxide

    International Nuclear Information System (INIS)

    Polakowski, Patrick; Müller, Johannes

    2015-01-01

    We report the observation of ferroelectric characteristics in undoped hafnium oxide thin films in a thickness range of 4–20 nm. The undoped films were fabricated using atomic layer deposition (ALD) and embedded into titanium nitride based metal-insulator-metal (MIM) capacitors for electrical evaluation. Structural as well as electrical evidence for the appearance of a ferroelectric phase in pure hafnium oxide was collected with respect to film thickness and thermal budget applied during titanium nitride electrode formation. Using grazing incidence X-Ray diffraction (GIXRD) analysis, we observed an enhanced suppression of the monoclinic phase fraction in favor of an orthorhombic, potentially, ferroelectric phase with decreasing thickness/grain size and for a titanium nitride electrode formation below crystallization temperature. The electrical presence of ferroelectricity was confirmed using polarization measurements. A remanent polarization P r of up to 10 μC cm −2 as well as a read/write endurance of 1.6 × 10 5 cycles was measured for the pure oxide. The experimental results reported here strongly support the intrinsic nature of the ferroelectric phase in hafnium oxide and expand its applicability beyond the doped systems

  9. Plasma electrolytic oxidation of metals

    Directory of Open Access Journals (Sweden)

    Stojadinović Stevan

    2013-01-01

    Full Text Available In this lecture results of the investigation of plasma electrolytic oxidation (PEO process on some metals (aluminum, titanium, tantalum, magnesium, and zirconium were presented. Whole process involves anodizing metals above the dielectric breakdown voltage where numerous micro-discharges are generated continuously over the coating surface. For the characterization of PEO process optical emission spectroscopy and real-time imaging were used. These investigations enabled the determination of electron temperature, electron number density, spatial density of micro-discharges, the active surface covered by micro-discharges, and dimensional distribution of micro-discharges at various stages of PEO process. Special attention was focused on the results of the study of the morphology, chemical, and phase composition of oxide layers obtained by PEO process on aluminum, tantalum, and titanium in electrolytes containing tungsten. Physicochemical methodes: atomic force microscopy (AFM, scanning electron microscopy (SEM-EDS, x-ray diffraction (XRD, x-ray photoelectron spectroscopy (XPS, and Raman spectroscopy served as tools for examining obtained oxide coatings. Also, the application of the obtained oxide coatings, especially the application of TiO2/WO3 coatings in photocatalysis, were discussed.

  10. In-Situ Chemical Oxidation

    Science.gov (United States)

    2006-08-01

    wells at a bioremediation field site (Weisner et al., 1996). Colloidal clay particles mobilized during injec- tion have resulted in permeability losses...phase material. Nevertheless, O3 was readily delivered and transported through unsaturated porous media where phenanthrene and diesel range...tion, but is not currently a well-developed technology. Bioremediation : Sequencing oxidation and reduction reactions may be achieved through

  11. Riboflavin photosensitized oxidation of myoglobin.

    Science.gov (United States)

    Grippa, Juliana M; de Zawadzki, Andressa; Grossi, Alberto B; Skibsted, Leif H; Cardoso, Daniel R

    2014-02-05

    The reaction of the fresh meat pigment oxymyoglobin, MbFe(II)O₂, and its oxidized form metmyoglobin, MbFe(III), with triplet-state riboflavin involves the pigment protein, which is oxidatively cleaved or dimerized as shown by SDS-PAGE and Western blotting. The overall rate constant for oxidation of MbFe(II)O₂ by ³Rib is (3.0 ± 0.5) × 10⁹ L·mol⁻¹·s⁻¹ and (3.1 ± 0.4) × 10⁹ L·mol⁻¹·s⁻¹ for MbFe(III) in phosphate buffer of pH 7.4 at 25 °C as determined by laser flash photolysis. The high rates are rationalized by ground state hydrophobic interactions as detected as static quenching of fluorescence from singlet-excited state riboflavin by myoglobins using time-resolved fluorescence spectroscopy and a Stern-Volmer approach. Binding of riboflavin to MbFe(III) has K(a) = (1.2 ± 0.2) × 10⁴ mol·L⁻¹ with ΔH° = -112 ± 22 kJ·mol⁻¹ and ΔS° = -296 ± 75 J·mol⁻¹·K⁻¹. For meat, riboflavin is concluded to be a photosensitizer for protein oxidation but not for discoloration.

  12. Radiation annealing in cuprous oxide

    DEFF Research Database (Denmark)

    Vajda, P.

    1966-01-01

    Experimental results from high-intensity gamma-irradiation of cuprous oxide are used to investigate the annealing of defects with increasing radiation dose. The results are analysed on the basis of the Balarin and Hauser (1965) statistical model of radiation annealing, giving a square...

  13. Perovskite catalysts for oxidative coupling

    Science.gov (United States)

    Campbell, Kenneth D.

    1991-01-01

    Perovskites of the structure A.sub.2 B.sub.2 C.sub.3 O.sub.10 are useful as catalysts for the oxidative coupling of lower alkane to heavier hydrocarbons. A is alkali metal; B is lanthanide or lanthanum, cerium, neodymium, samarium, praseodymium, gadolinium or dysprosium; and C is titanium.

  14. Corium Oxidation at Temperatures Above 2000 K

    International Nuclear Information System (INIS)

    Hagrman, Donald L.; Rempe, Joy L.

    2001-01-01

    A mechanistic model, based on a quasi-equilibrium analysis of oxidation reactions, is proposed for predicting high-temperature corium oxidation. The analysis suggests that oxide forming on the surface of corium containing uranium, zirconium, and iron is similar to the oxides formed on zirconium and uranium as long as there is a small percentage of unoxidized zirconium or uranium in the metallic phase. This is because of the higher affinity of zirconium and uranium for oxygen. Hence, oxidation rates and heat production rates are similar to (U,Zr) compounds until nearly all the uranium and zirconium in the corium oxidizes. Oxidation rates after this point are predicted to be similar to those implied by the oxide thickness present when the forming oxide ceases to be protective, and heat generation rates should be similar to those implied by iron oxidation, i.e., ∼4% of the zirconium oxidation heating rate.The maximum atomic ratio of unoxidized iron to unoxidized liquid zirconium plus uranium for the formation of a solid protective oxide below 2800 K is estimated for a temperature, T (in Kelvin), as follows:(unoxidized iron)/(unoxidized zirconium + turanium) = (1/28){5.7/exp[-(147 061 + 12.08T log(T) - 61.03T - 0.000555T 2 /1.986T)]} 1/2 .As long as this limit is not exceeded, either zirconium or uranium metal oxidation rates and heating describe the corium oxidation rate. If this limit is exceeded, diffusion of steam to the corium surface will limit the oxidation rate, and linear time-dependent growth of a nonprotective, mostly FeO, layer will occur below the protective (Zr,U) O 2 scale. When this happens, the oxidation should be at the constant rate given by the thickness of the protective layer. Heat generation should be similar to that of iron oxidation

  15. Corium Oxidation at Temperatures Above 2000 K

    Energy Technology Data Exchange (ETDEWEB)

    Hagrman, Donald Lee; Rempe, Joy Lynn

    2001-02-01

    A mechanistic model, based on a quasi-equilibrium analysis of oxidation reactions, is proposed for predicting high-temperature corium oxidation. The analysis suggests that oxide forming on the surface of corium containing uranium, zirconium, and iron is similar to the oxides formed on zirconium and uranium as long as there is a small percentage of unoxidized zirconium or uranium in the metallic phase. This is because of the higher affinity of zirconium and uranium for oxygen. Hence, oxidation rates and heat production rates are similar to (U,Zr) compounds until nearly all the uranium and zirconium in the corium oxidizes. Oxidation rates after this point are predicted to be similar to those implied by the oxide thickness present when the forming oxide ceases to be protective, and heat generation rates should be similar to those implied by iron oxidation, i.e., ~4% of the zirconium oxidation heating rate. The maximum atomic ratio of unoxidized iron to unoxidized liquid zirconium plus uranium for the formation of a solid protective oxide below 2800 K is estimated for a temperature, T (in Kelvin), as follows: (unoxidized iron)/(unoxidized zirconium + turanium) = (1/28){5.7/exp[-(147 061 + 12.08T log(T) - 61.03T - 0.000555T2/1.986T)]}1/2. As long as this limit is not exceeded, either zirconium or uranium metal oxidation rates and heating describe the corium oxidation rate. If this limit is exceeded, diffusion of steam to the corium surface will limit the oxidation rate, and linear time-dependent growth of a nonprotective, mostly FeO, layer will occur below the protective (Zr,U) O2 scale. When this happens, the oxidation should be at the constant rate given by the thickness of the protective layer. Heat generation should be similar to that of iron oxidation.

  16. Oxidation of pyrite: Consequences and significance

    Directory of Open Access Journals (Sweden)

    Dimitrijević Mile D.

    2002-01-01

    Full Text Available This paper presents the most important studies on the oxidation of pyrite particularly in aqueous solutions. The consequences of pyrite oxidation was examined, as well as its importance, from both the technical-technological and environmental points of view. The oxidation of pyrite was considered in two parts. The spontaneous oxidation of pyrite in nature was described in the first part, with this part comprising pyrite oxidation in deposits depots and mines. It is explained how way natural electrochemical processes lead to the decomposition of pyrite and other minerals associated with pyrite. The oxidation of pyrite occurring during technological processes such as grinding, flotation and leaching, was shown in the second part. Particular emphasis was placed on the oxidation of pyrite during leaching. This part includes the leaching of sulphide and oxide ores, the leaching of pyrite coal and the leaching of refractory gold-bearing ores (pressure oxidation, bacterial oxidation, oxidation by means of strong oxidants and the electrolysis of pyrite suspensions. Various mechanisms of pyrite oxidation and of the galvanic interaction of pyrite with other sulphide minerals are shown.

  17. Selective propene oxidation on mixed metal oxide catalysts

    International Nuclear Information System (INIS)

    James, David William

    2002-01-01

    Selective catalytic oxidation processes represent a large segment of the modern chemical industry and a major application of these is the selective partial oxidation of propene to produce acrolein. Mixed metal oxide catalysts are particularly effective in promoting this reaction, and the two primary candidates for the industrial process are based on iron antimonate and bismuth molybdate. Some debate exists in the literature regarding the operation of these materials and the roles of their catalytic components. In particular, iron antimonate catalysts containing excess antimony are known to be highly selective towards acrolein, and a variety of proposals for the enhanced selectivity of such materials have been given. The aim of this work was to provide a direct comparison between the behaviour of bismuth molybdate and iron antimonate catalysts, with additional emphasis being placed on the component single oxide phases of the latter. Studies were also extended to other antimonate-based catalysts, including cobalt antimonate and vanadium antimonate. Reactivity measurements were made using a continuous flow microreactor, which was used in conjunction with a variety of characterisation techniques to determine relationships between the catalytic behaviour and the properties of the materials. The ratio of Fe/Sb in the iron antimonate catalyst affects the reactivity of the system under steady state conditions, with additional iron beyond the stoichiometric value being detrimental to the acrolein selectivity, while extra antimony provides a means of enhancing the selectivity by decreasing acrolein combustion. Studies on the single antimony oxides of iron antimonate have shown a similarity between the reactivity of 'Sb 2 O 5 ' and FeSbO 4 , and a significant difference between these and the Sb 2 O 3 and Sb 2 O 4 phases, implying that the mixed oxide catalyst has a surface mainly comprised of Sb 5+ . The lack of reactivity of Sb 2 O 4 implies a similarity of the surface with

  18. Nanostructured manganese oxide/carbon nanotubes, graphene and graphene oxide as water-oxidizing composites in artificial photosynthesis.

    Science.gov (United States)

    Najafpour, Mohammad Mahdi; Rahimi, Fahime; Fathollahzadeh, Maryam; Haghighi, Behzad; Hołyńska, Małgorzata; Tomo, Tatsuya; Allakhverdiev, Suleyman I

    2014-07-28

    Herein, we report on nano-sized Mn oxide/carbon nanotubes, graphene and graphene oxide as water-oxidizing compounds in artificial photosynthesis. The composites are synthesized by different and simple procedures and characterized by a number of methods. The water-oxidizing activities of these composites are also considered in the presence of cerium(IV) ammonium nitrate. Some composites are efficient Mn-based catalysts with TOF (mmol O2 per mol Mn per second) ~ 2.6.

  19. Oxidative stress in cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Shyamal K Goswami

    2015-01-01

    Full Text Available Oxidative stress caused by various oxygen containing free radicals and reactive species (collectively called "Reactive Oxygen Species" or ROS has long been attributed to cardiovascular diseases. In human body, major oxidizing species are super oxide, hydrogen peroxide, hydroxyl radical, peroxy nitrite etc. ROS are produced from distinct cellular sources, enzymatic and non-enzymatic; have specific physicochemical properties and often have specific cellular targets. Although early studies in nineteen sixties and seventies highlighted the deleterious effects of these species, later it was established that they also act as physiological modulators of cellular functions and diseases occur only when ROS production is deregulated. One of the major sources of cellular ROS is Nicotinamide adenine dinucleotide phosphate oxidases (Noxes that are expressed in almost all cell types. Superoxide and hydrogen peroxide generated from them under various conditions act as signal transducers. Due to their immense importance in cellular physiology, various Nox inhibitors are now being developed as therapeutics. Another free radical of importance in cardiovascular system is nitric oxide (a reactive nitrogen species generated from nitric oxide synthase(s. It plays a critical role in cardiac function and its dysregulated generation along with superoxide leads to the formation of peroxynitrite a highly deleterious agent. Despite overwhelming evidences of association between increased level of ROS and cardiovascular diseases, antioxidant therapies using vitamins and omega 3 fatty acids have largely been unsuccessful till date. Also, there are major discrepancies between studies with laboratory animals and human trials. It thus appears that the biology of ROS is far complex than anticipated before. A comprehensive understanding of the redox biology of diseases is thus needed for developing targeted therapeutics.

  20. The properties of protective oxide scales containing cerium on alloy 800H in oxidizing and oxidizing/sulphidizing environments

    NARCIS (Netherlands)

    Haanappel, V.A.C.; Haanappel, V.A.C.; Fransen, T.; Geerdink, Bert; Gellings, P.J.; Stroosnijder, M.F.

    1991-01-01

    The corrosion protection of oxide scales formed by electrophoretic deposition in a cerium-containing sol on Alloy 800H, a 32Ni-20Cr steel, followed by firing in air at 1123 K was studied in oxidizing and mixed oxidizing/sulphidizing environments at elevated temperatures. In particular, the influence

  1. Experimental investigation and thermodynamic simulation of the uranium oxide-zirconium oxide-iron oxide system in air

    Czech Academy of Sciences Publication Activity Database

    Petrov, Y. B.; Udalov, Y. P.; Šubrt, Jan; Bakardjieva, Snejana; Sázavský, P.; Kiselová, M.; Selucký, P.; Bezdička, Petr; Joumeau, C.; Piluso, P.

    2011-01-01

    Roč. 37, č. 2 (2011), s. 212-229 ISSN 1087-6596 Institutional research plan: CEZ:AV0Z40320502 Keywords : uranium oxide * zirconium oxide * iron oxide * fusibility curve * oxygen partial pressure * crystallization * phase composition Subject RIV: CA - Inorganic Chemistry Impact factor: 0.492, year: 2011

  2. "UCx fission targets oxidation test stand"

    CERN Document Server

    Lacroix, Rachel

    2014-01-01

    "Set up a rig dedicated to the oxidation of UCx and define a procedure for repeatable, reliable and safe method for converting UC2 fission targets into an acceptable uranium carbide oxide waste for subsequent disposal by the Swiss Authorities."

  3. Methods for synthesizing metal oxide nanowires

    Science.gov (United States)

    Sunkara, Mahendra Kumar; Kumar, Vivekanand; Kim, Jeong H.; Clark, Ezra Lee

    2016-08-09

    A method of synthesizing a metal oxide nanowire includes the steps of: combining an amount of a transition metal or a transition metal oxide with an amount of an alkali metal compound to produce a mixture; activating a plasma discharge reactor to create a plasma discharge; exposing the mixture to the plasma discharge for a first predetermined time period such that transition metal oxide nanowires are formed; contacting the transition metal oxide nanowires with an acid solution such that an alkali metal ion is exchanged for a hydrogen ion on each of the transition metal oxide nanowires; and exposing the transition metal oxide nanowires to the plasma discharge for a second predetermined time period to thermally anneal the transition metal oxide nanowires. Transition metal oxide nanowires produced using the synthesis methods described herein are also provided.

  4. Consecutive dynamic resolutions of phosphine oxides

    NARCIS (Netherlands)

    Kortmann, Felix A.; Chang, Mu-Chieh; Otten, Edwin; Couzijn, Erik P. A.; Lutz, Martin; Minnaard, Adriaan J.

    2013-01-01

    A crystallization-induced asymmetric transformation (CIAT) involving a radical-mediated racemization provides access to enantiopure secondary phosphine oxides. A consecutive CIAT is used to prepare enantio-and diastereo-pure tert-butyl(hydroxyalkyl)phenylphosphine oxides.

  5. Oxidation catalysts and process for preparing same

    International Nuclear Information System (INIS)

    1980-01-01

    Compounds particularly suitable as oxidation catalysis are described, comprising specified amounts of uranium, antimony and tin as oxides. Processes for making and using the catalysts are described. (U.K.)

  6. Transparent Oxide Semiconductors for Emerging Electronics

    KAUST Repository

    Caraveo-Frescas, Jesus Alfonso

    2013-01-01

    Transparent oxide electronics have emerged as promising materials to shape the future of electronics. While several n-type oxides have been already studied and demonstrated feasibility to be used as active materials in thin film transistors, high

  7. Electrochemical, Chemical and Enzymatic Oxidations of Phenothiazines

    NARCIS (Netherlands)

    Blankert, B.; Hayen, H.; van Leeuwen, S.M.; Karst, U.; Bodoki, E.; Lotrean, S.; Sandulescu, R.; Mora Diaz, N.; Dominguez, O.; Arcos, J.; Kauffmann, J.-M.

    2005-01-01

    The oxidation of several phenothiazine drugs (phenothiazine, promethazine hydrochloride, promazine hydrochloride, trimeprazine hydrochloride and ethopropazine hydrochloride) has been carried out in aqueous acidic media by electrochemical, chemical and enzymatic methods. The chemical oxidation was

  8. Nanostructured Thermoelectric Oxides for Energy Harvesting Applications

    KAUST Repository

    Abutaha, Anas I.

    2015-01-01

    of thermoelectrics are still limited to one materials system, namely SiGe, since the traditional thermoelectric materials degrade and oxidize at high temperature. Therefore, oxide thermoelectrics emerge as a promising class of materials since they can operate

  9. Oxidation of boron carbide at high temperatures

    International Nuclear Information System (INIS)

    Steinbrueck, Martin

    2005-01-01

    The oxidation kinetics of various types of boron carbides (pellets, powder) were investigated in the temperature range between 1073 and 1873 K. Oxidation rates were measured in transient and isothermal tests by means of mass spectrometric gas analysis. Oxidation of boron carbide is controlled by the formation of superficial liquid boron oxide and its loss due to the reaction with surplus steam to volatile boric acids and/or direct evaporation at temperatures above 1770 K. The overall reaction kinetics is paralinear. Linear oxidation kinetics established soon after the initiation of oxidation under the test conditions described in this report. Oxidation is strongly influenced by the thermohydraulic boundary conditions and in particular by the steam partial pressure and flow rate. On the other hand, the microstructure of the B 4 C samples has a limited influence on oxidation. Very low amounts of methane were produced in these tests

  10. Solid Oxide Fuel Cell Experimental Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — NETL’s Solid Oxide Fuel Cell Experimental Laboratory in Morgantown, WV, gives researchers access to models and simulations that predict how solid oxide fuel cells...

  11. Sodium Perborate Oxidation of an Aromatic Amine

    Science.gov (United States)

    Juestis, Laurence

    1977-01-01

    Describes an experiment involving the oxidation of aromatic primary amines to the corresponding azo compound; suggests procedures for studying factors that influence the yield of such a reaction, including the choice of solvent and the oxidant-amine ratio. (MLH)

  12. Clinical Relevance of Biomarkers of Oxidative Stress

    DEFF Research Database (Denmark)

    Frijhoff, Jeroen; Winyard, Paul G; Zarkovic, Neven

    2015-01-01

    SIGNIFICANCE: Oxidative stress is considered to be an important component of various diseases. A vast number of methods have been developed and used in virtually all diseases to measure the extent and nature of oxidative stress, ranging from oxidation of DNA to proteins, lipids, and free amino ac....... The vast diversity in oxidative stress between diseases and conditions has to be taken into account when selecting the most appropriate biomarker.......SIGNIFICANCE: Oxidative stress is considered to be an important component of various diseases. A vast number of methods have been developed and used in virtually all diseases to measure the extent and nature of oxidative stress, ranging from oxidation of DNA to proteins, lipids, and free amino...... acids. RECENT ADVANCES: An increased understanding of the biology behind diseases and redox biology has led to more specific and sensitive tools to measure oxidative stress markers, which are very diverse and sometimes very low in abundance. CRITICAL ISSUES: The literature is very heterogeneous...

  13. Periodontitis and increase in circulating oxidative stress

    OpenAIRE

    Takaaki Tomofuji; Koichiro Irie; Toshihiro Sanbe; Tetsuji Azuma; Daisuke Ekuni; Naofumi Tamaki; Tatsuo Yamamoto; Manabu Morita

    2009-01-01

    Reactive oxygen species (ROS) are products of normal cellular metabolism. However, excessive production of ROS oxidizes DNA, lipids and proteins, inducing tissue damage. Studies have shown that periodontitis induces excessive ROS production in periodontal tissue. When periodontitis develops, ROS produced in the periodontal lesion diffuse into the blood stream, resulting in the oxidation of blood molecules (circulating oxidative stress). Such oxidation may be detrimental to systemic health. Fo...

  14. Diesel soot oxidation under controlled conditions

    OpenAIRE

    Song, Haiwen

    2003-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University, 11/12/2003. In order to improve understanding of diesel soot oxidation, an experimental rig was designed and set up, in which the soot oxidation conditions, such as temperature, oxygen partial pressure, and CO2 partial pressure, could be varied independently of each other. The oxidizing gas flow in the oxidizer was under laminar condition. This test rig comprised a naturally-aspirated single ...

  15. Mechanisms of wet oxidation by hydrogen peroxide

    International Nuclear Information System (INIS)

    Baxter, R.A.

    1987-08-01

    A research programme is currently under way at BNL and MEL to investigate the possible use of Hydrogen Peroxide with metal ion catalysts as a wet oxidation treatment system for CEGB organic radioactive wastes. The published literature relating to the kinetics and mechanism of oxidation and decomposition reactions of hydrogen peroxide is reviewed and the links with practical waste management by wet oxidation are examined. Alternative wet oxidation systems are described and the similarities to the CEGB research effort are noted. (author)

  16. Oxidation of 1-butene over uranium oxide (UO3)-antimony oxide (Sb2O3) catalysts

    NARCIS (Netherlands)

    Simons, T.; Houtman, P.N.; Schuit, G.C.A.

    1971-01-01

    The oxidative dehydrogenation of butene to butadiene over U-Sb catalysts was investigated. The presence of two compds., (UO2)Sb3O7 and Sb3U3O14, reported by Grasselli and Callahan (1969), was confirmed with (UO2)Sb3O7 being the actual catalyst. The reaction is first order in butene and zero order in

  17. Absorption and oxidation of nitrogen oxide in ionic liquids

    DEFF Research Database (Denmark)

    Kunov-Kruse, Andreas Jonas; Thomassen, Peter Langelund; Riisager, Anders

    2016-01-01

    A new strategy for capturing nitrogen oxide, NO, from the gas phase is presented. Dilute NO gas is removed from the gas phase by ionic liquids under ambient conditions. The nitrate anion of the ionic liquid catalyzes the oxidation of NO to nitric acid by atmospheric oxygen in the presence of water....... The nitric acid is absorbed in the ionic liquid up to approximately one mole HNO3 per mole of the ionic liquid due to the formation of hydrogen bonds. The nitric acid can be desorbed by heating, thereby regenerating the ionic liquid with excellent reproducibility. Here, time-resolved in-situ spectroscopic...... investigations of the reaction and products are presented. The procedure reveals a new vision for removing the pollutant NO by absorption into a non-volatile liquid and converting it into a useful bulk chemical, that is, HNO3....

  18. The initial oxidation of magnesium

    Energy Technology Data Exchange (ETDEWEB)

    Kurth, M.

    2004-07-01

    Pure Magnesium samples have been oxidised in an UHV chamber under controlled conditions. Pressure range was 10{sup -10} Torr to 10{sup -7} Torr, temperature range was 273 K to 435 K. The samples have then been investigated with XPS, Ellipsometry and HERDA. Additionally, furnace oxidations at 750 Torr and 673 K have been carried out and investigated with XPS. From the XPS measurements data concerning layer thickness, composition, oxidation state and binding state have been gained. The ellipsometrie measurements yielded additional data concerning layer thickness as well as the size of the band gap of the developing oxide. With the HERDA measurements, the oxygen content within the oxide layer has been determined yielding additional information about composition and layer thickness. The layer thickness as a function of time have then been modelled with a kinetic growth model of Fromhold and Cook. For the refinement of the XPS data concerning layer thickness and composition, the pronounced plasmon excitations that occur in magnesium have been determined with two different procedures which have been developed in the methodical part of this work. The layer thickness and composition values have thus been corrected. Results: Two oxidation stages could be identified: a strong increase for the first few Langmuirs (1L = 1s x 10{sup -6} Torr), followed by a saturation'' region which was about 1.2 nm to 1.5 nm in magnitude. XPS and ellipsometry results have thereby been in very good agreement. The composition of the developing oxide showed a clear deviation from stoichiometric MgO, mainly caused by an oxygen deficiency; this deficiency has also been confirmed with the HERDA measurements. The Mg/O ratio as a function of layer thickness showed a continous decay starting from very high values for the thinnest layers (>{proportional_to}2.5) down to a saturation value of about 1.4, even for larger layer thicknesses gained with the furnace oxidations. The determination of

  19. New oxidation and photo-oxidation products of tryptophan

    International Nuclear Information System (INIS)

    Savige, W.E.

    1975-01-01

    Dye-sensitized photo-oxidation of tryptophan in water gives N'-formylkynurenine and (+-)-3a-hydroxy-1,2,3a,8,8a-hexahydropyrrolo[2,3-b] indole-2-carboxylic acid. The latter rearranges to oxindolyl-3-alanine on irradiation with UV light and reacts with thiols, including cysteine, in warm 20% acetic acid to give the corresponding 2-tryptophyl sulphides. (orig.) [de

  20. Dense high temperature ceramic oxide superconductors

    Science.gov (United States)

    Landingham, Richard L.

    1993-01-01

    Dense superconducting ceramic oxide articles of manufacture and methods for producing these articles are described. Generally these articles are produced by first processing these superconducting oxides by ceramic processing techniques to optimize materials properties, followed by reestablishing the superconducting state in a desired portion of the ceramic oxide composite.

  1. 21 CFR 582.1210 - Calcium oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium oxide. 582.1210 Section 582.1210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1210 Calcium oxide. (a) Product. Calcium oxide. (b) Conditions of use. This substance is generally...

  2. 21 CFR 582.5210 - Calcium oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium oxide. 582.5210 Section 582.5210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5210 Calcium oxide. (a) Product. Calcium oxide. (b) Conditions of use. This substance is...

  3. Free energy of hydration of niobium oxide

    International Nuclear Information System (INIS)

    Plodinec, M.J.

    1996-01-01

    Some of the glasses being formulated by SRTC researchers contain niobium oxide. In this report, the free energy of hydration of the oxide is calculated from the free energies of formation of the oxide, the hydroxide, and water. This value can be used in calculations of the free energy of hydration of glasses containing niobium

  4. 29 CFR 1910.105 - Nitrous oxide.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Nitrous oxide. 1910.105 Section 1910.105 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Hazardous Materials § 1910.105 Nitrous oxide. The piped systems for the in-plant transfer and distribution of nitrous oxide shall be designed, installed, maintained, and...

  5. Nitrous oxide emissions from estuarine intertidal sediments

    NARCIS (Netherlands)

    Middelburg, J.J.; Klaver, G.; Nieuwenhuize, J.; Markusse, R.M.; Vlug, T.; Nat, F.J.W.A. van der

    1995-01-01

    From September 1990 through December 1991 nitrous oxide flux measurements were made at 9 intertidal mud flat sites in the Scheldt Estuary. Nitrous oxide release rates were highly variable both between sites and over time at any one site. Annual nitrous oxide fluxes vary from about 10 mmol N m-2 at

  6. Separation medium containing thermally exfoliated graphite oxide

    Science.gov (United States)

    Prud'homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor); Herrera-Alonso, Margarita (Inventor)

    2012-01-01

    A separation medium, such as a chromatography filling or packing, containing a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m.sup.2/g to 2600 m.sup.2/g, wherein the thermally exfoliated graphite oxide has a surface that has been at least partially functionalized.

  7. Air Quality Criteria for Sulfur Oxides.

    Science.gov (United States)

    National Air Pollution Control Administration (DHEW), Washington, DC.

    Included is a literature review which comprehensively discusses knowledge of the sulfur oxides commonly found in the atmosphere. The subject content is represented by the 10 chapter titles: Physical and Chemical Properties and the Atmospheric Reactions of the Oxides of Sulfur; Sources and Methods of Measurements of Sulfur Oxides in the Atmosphere;…

  8. Graphene oxide reduction recipes, spectroscopy, and applications

    CERN Document Server

    Gao, Wei

    2015-01-01

    This book focuses on a group of new materials labeled ""graphene oxides."" It provides a comprehensive overview of graphene oxide-based nanomaterials in terms of their synthesis, structures, properties, and extensive applications in catalysis, separation, filtration, energy storage and conversion. The book also covers emerging research on graphite oxides and the impact of the research on fundamental and applied sciences.

  9. 49 CFR 173.323 - Ethylene oxide.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Ethylene oxide. 173.323 Section 173.323... SHIPMENTS AND PACKAGINGS Gases; Preparation and Packaging § 173.323 Ethylene oxide. (a) For packaging ethylene oxide in non-bulk packagings, silver mercury or any of its alloys or copper may not be used in any...

  10. 29 CFR 1910.1047 - Ethylene oxide.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 6 2010-07-01 2010-07-01 false Ethylene oxide. 1910.1047 Section 1910.1047 Labor... Ethylene oxide. (a) Scope and application. (1) This section applies to all occupational exposures to ethylene oxide (EtO), Chemical Abstracts Service Registry No. 75-21-8, except as provided in paragraph (a...

  11. On chemical activity of heavy metal oxides

    International Nuclear Information System (INIS)

    Mechev, V.V.

    1994-01-01

    Interaction of solid oxides of heavy nonferrous metals with sulfur and carbon is investigated. The results are discussed. Direct dependence of chemical activity of oxides on disordering of their crystal lattice at heating is established. Beginning of interaction in the systems studied is accompanied by change of oxide conductivity type

  12. 21 CFR 582.5431 - Magnesium oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Magnesium oxide. 582.5431 Section 582.5431 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5431 Magnesium oxide. (a) Product. Magnesium oxide. (b) Conditions of use. This substance...

  13. 21 CFR 582.1431 - Magnesium oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Magnesium oxide. 582.1431 Section 582.1431 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1431 Magnesium oxide. (a) Product. Magnesium oxide. (b) Conditions of use. This substance is...

  14. 21 CFR 184.1431 - Magnesium oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium oxide. 184.1431 Section 184.1431 Food and... Substances Affirmed as GRAS § 184.1431 Magnesium oxide. (a) Magnesium oxide (MgO, CAS Reg. No. 1309-48-4... powder (light) or a relatively dense white powder (heavy) by heating magnesium hydroxide or carbonate...

  15. 21 CFR 73.3125 - Iron oxides.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Iron oxides. 73.3125 Section 73.3125 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3125 Iron oxides. (a) Identity and specifications. The color additive iron oxides (CAS Reg. No. 1332-37-2), Color Index No. 77491, shall conform in...

  16. Synthesis of vertically aligned metal oxide nanostructures

    KAUST Repository

    Roqan, Iman S.; Flemban, Tahani H.

    2016-01-01

    ablation of a target including a metal oxide and, optionally, a dopant. In some embodiments zinc oxide nanostructures are deposited onto a substrate by pulsed laser deposition of a zinc oxide target using an excimer laser emitting UV radiation. The zinc

  17. Structure and catalytic reactivity of Rh oxides

    DEFF Research Database (Denmark)

    Gustafson, J.; Westerström, R.; Resta, A.

    2009-01-01

    Using a combination of experimental and theoretical techniques, we show that a thin RhO2 surface oxide film forms prior to the bulk Rh2O3 corundum oxide on all close-packed single crystal Rh surfaces. Based on previous reports, we argue that the RhO2 surface oxide also forms on vicinal Rh surface...

  18. Limits to the adherence of oxide scales

    International Nuclear Information System (INIS)

    Robertson, J.; Manning, M.I.

    1989-10-01

    Fracture mechanics is used to identify criteria under which uniform oxide scales may be expected to fail due to rapidly applied strains. The most common failure mode occurs when the strain, ε, builds up in the scale until the strain energy density per unit area exceeds the fracture surface energy, γ, of the oxide. This produces spalling when ε > (2γ/hE) 1/2 , where h is the scale thickness and E is the oxide Youngs modulus. In thin scales, as the external strain is applied to the oxide via the metal substrate, it is clear that no further strain can be applied to the oxide if the substrate has itself been strained beyond yield. This gives rise to extended oxide adherence in which the oxide cracks and forms a series of islands but remains attached to the deformed metal. When the oxide thickness is less than its comminution limit, the flaw size necessary for brittle fracture exceeds the oxide thickness and the oxide yields in a ductile manner without cracking. The results are presented as maps of failure strain versus oxide thickness for various oxide systems such as Fe 3 O 4 , Cr 2 O 3 , Al 2 O 3 , SiO 2 and NiO. The observed cases of spalling are found to lie within the predicted regions. (author)

  19. Shocked plate metal atom oxidation laser

    International Nuclear Information System (INIS)

    De Koker, J.G.; Rice, W.W. Jr.; Jensen, R.J.

    1975-01-01

    A method and apparatus for producing metal atom oxidation lasing wherein an explosively shocked grooved metal plate produces metal vapor jets directed through an appropriate gaseous oxidizer are described. Reaction of the metal vapor with the oxidizer produces molecular species having a population inversion therein. (U.S.)

  20. Oxidized Lipoprotein as a Major Vessel Cell Proliferator in Oxidized Human Serum.

    Directory of Open Access Journals (Sweden)

    Yoshiro Saito

    Full Text Available Oxidative stress is correlated with the incidence of several diseases such as atherosclerosis and cancer, and oxidized biomolecules have been determined as biomarkers of oxidative stress; however, the detailed molecular relationship between generated oxidation products and the promotion of diseases has not been fully elucidated. In the present study, to clarify the role of serum oxidation products in vessel cell proliferation, which is related to the incidence of atherosclerosis and cancer, the major vessel cell proliferator in oxidized human serum was investigated. Oxidized human serum was prepared by free radical exposure, separated using gel chromatography, and then each fraction was added to several kinds of vessel cells including endothelial cells and smooth muscle cells. It was found that a high molecular weight fraction in oxidized human serum specifically induced vessel cell proliferation. Oxidized lipids were contained in this high molecular weight fraction, while cell proliferation activity was not observed in oxidized lipoprotein-deficient serum. Oxidized low-density lipoproteins induced vessel cell proliferation in a concentration-dependent manner. Taken together, these results indicate that oxidized lipoproteins containing lipid oxidation products function as a major vessel cell proliferator in oxidized human serum. These findings strongly indicate the relevance of determination of oxidized lipoproteins and lipid oxidation products in the diagnosis of vessel cell proliferation-related diseases such as atherosclerosis and cancer.

  1. Advanced methods for the treatment of organic aqueous wastes: wet air oxidation and wet peroxide oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Debellefontaine, Hubert; Chakchouk, Mehrez; Foussard, Jean Noel [Institut National des Sciences Appliquees (INSA), 31 - Toulouse (France). Dept. de Genie des Procedes Industriels; Tissot, Daniel; Striolo, Phillipe [IDE Environnement S.A., Toulouse (France)

    1993-12-31

    There is a growing concern about the problems of wastes elimination. Various oxidation techniques are suited for elimination of organic aqueous wastes, however, because of the environmental drawbacks of incineration, liquid phase oxidation should be preferred. `Wet Air Oxidation` and `Wet Peroxide Oxidation`are alternative processes which are discussed in this paper. 17 refs., 13 figs., 4 tabs.

  2. Polyaniline: Aniline oxidation with strong and weak oxidants under various acidity

    Energy Technology Data Exchange (ETDEWEB)

    Bláha, Michal, E-mail: blaha@imc.cas.cz [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6 (Czech Republic); Trchová, Miroslava; Bober, Patrycja; Morávková, Zuzana [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6 (Czech Republic); Prokeš, Jan [Charles University, Faculty of Mathematics and Physics, 180 00 Prague 8 (Czech Republic); Stejskal, Jaroslav [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6 (Czech Republic)

    2017-06-15

    Aniline was oxidized with three strong inorganic oxidants (ammonium peroxydisulfate, cerium(IV) sulfate, potassium dichromate), two weak inorganic oxidants (iron(III) chloride, silver nitrate), and one organic oxidant (p-benzoquinone) in aqueous solutions of methanesulfonic acid (MSA) of various concentration. Whereas oxidation of aniline with ammonium peroxydisulfate yielded high-molecular-weight conducting polyaniline (PANI) in the whole acidity range, the oxidation with cerium(IV) sulfate led also to a single product close to PANI with considerably lower molecular weight and lower conductivity. Potassium dichromate gave PANI only at high concentration of MSA. The use of iron(III) chloride yielded composite mixtures of PANI and low-molecular-weight aniline oligomers. The oxidation of aniline with silver nitrate led to composites of silver and an organic part, which was constituted either by aniline oligomers or conducting polyaniline or both. p-Benzoquinone as oxidant produced mainly aniline oligomers with poor conductivity and 2,5-dianilino-p-benzoquinone-like structure detected in FTIR and Raman spectra when oxidation proceeded with weak oxidants. A general model of oxidation with strong and weak oxidants was formulated. - Highlights: • Comparison of aniline oxidation with oxidants of different redox potential. • UV–vis, FTIR and Raman spectroscopies combined with size-exclusion chromatography. • The contents of polymer and oligomers were analyzed and discussed. • General model of aniline oxidation with strong and weak oxidants was formulated.

  3. Advanced methods for the treatment of organic aqueous wastes: wet air oxidation and wet peroxide oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Debellefontaine, Hubert; Chakchouk, Mehrez; Foussard, Jean Noel [Institut National des Sciences Appliquees (INSA), 31 - Toulouse (France). Dept. de Genie des Procedes Industriels; Tissot, Daniel; Striolo, Phillipe [IDE Environnement S.A., Toulouse (France)

    1994-12-31

    There is a growing concern about the problems of wastes elimination. Various oxidation techniques are suited for elimination of organic aqueous wastes, however, because of the environmental drawbacks of incineration, liquid phase oxidation should be preferred. `Wet Air Oxidation` and `Wet Peroxide Oxidation`are alternative processes which are discussed in this paper. 17 refs., 13 figs., 4 tabs.

  4. Fatty acid omega-oxidation as a rescue pathway for fatty acid oxidation disorders in humans

    NARCIS (Netherlands)

    Wanders, Ronald J. A.; Komen, Jasper; Kemp, Stephan

    2011-01-01

    Fatty acids (FAs) can be degraded via different mechanisms including alpha-, beta- and omega-oxidation. In humans, a range of different genetic diseases has been identified in which either mitochondrial FA beta-oxidation, peroxisomal FA beta-oxidation or FA alpha-oxidation is impaired. Treatment

  5. Production of oceanic nitrous oxide by ammonia-oxidizing archaea

    Directory of Open Access Journals (Sweden)

    C. R. Löscher

    2012-07-01

    Full Text Available The recent finding that microbial ammonia oxidation in the ocean is performed by archaea to a greater extent than by bacteria has drastically changed the view on oceanic nitrification. The numerical dominance of archaeal ammonia-oxidizers (AOA over their bacterial counterparts (AOB in large parts of the ocean leads to the hypothesis that AOA rather than AOB could be the key organisms for the oceanic production of the strong greenhouse gas nitrous oxide (N2O that occurs as a by-product of nitrification. Very recently, enrichment cultures of marine ammonia-oxidizing archaea have been reported to produce N2O.

    Here, we demonstrate that archaeal ammonia monooxygenase genes (amoA were detectable throughout the water column of the eastern tropical North Atlantic (ETNA and eastern tropical South Pacific (ETSP Oceans. Particularly in the ETNA, comparable patterns of abundance and expression of archaeal amoA genes and N2O co-occurred in the oxygen minimum, whereas the abundances of bacterial amoA genes were negligible. Moreover, selective inhibition of archaea in seawater incubations from the ETNA decreased the N2O production significantly. In studies with the only cultivated marine archaeal ammonia-oxidizer Nitrosopumilus maritimus SCM1, we provide the first direct evidence for N2O production in a pure culture of AOA, excluding the involvement of other microorganisms as possibly present in enrichments. N. maritimus showed high N2O production rates under low oxygen concentrations comparable to concentrations existing in the oxycline of the ETNA, whereas the N2O production from two AOB cultures was comparably low under similar conditions. Based on our findings, we hypothesize that the production of N2O in tropical ocean areas results mainly from archaeal nitrification and will be affected by the predicted decrease in dissolved

  6. Synthesis of Graphene Oxide by Oxidation of Graphite with Ferrate(VI) Compounds: Myth or Reality?

    Science.gov (United States)

    Sofer, Zdeněk; Luxa, Jan; Jankovský, Ondřej; Sedmidubský, David; Bystroň, Tomáš; Pumera, Martin

    2016-09-19

    It is well established that graphene oxide can be prepared by the oxidation of graphite using permanganate or chlorate in an acidic environment. Recently, however, the synthesis of graphene oxide using potassium ferrate(VI) ions has been reported. Herein, we critically replicate and evaluate this new ferrate(VI) oxidation method. In addition, we test the use of potassium ferrate(VI) for the synthesis of graphene oxide under various experimental routes. The synthesized materials are analyzed by a number of analytical methods in order to confirm or disprove the possibility of synthesizing graphene oxide by the ferrate(VI) oxidation route. Our results confirm the unsuitability of using ferrate(VI) for the oxidation of graphite on graphene oxide because of its high instability in an acidic environment and low oxidation power in neutral and alkaline environments. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Contribution to characteristics of uranium oxides

    International Nuclear Information System (INIS)

    Fritsche, R.; Dahlkamp, F.J.

    2001-01-01

    Uranium oxides from pegmatitic, metamorphic and metasomatic uranium occurrences were investigated with the objective to check for differences in their physico-chemical properties and, whether such properties are sufficiently distinct to be applied as an exploration tool. Research methods included microscopy, electron microprobe and X-ray diffractometry amended by determinations of reflectance, Vickers hardness, unit-cell dimension and oxidation grade. Tentative research results are as follows: (a) U-oxides (uraninites) of pegmatites always contain significant amounts of Th (1,5-10 wt.% ThO2). (b) U-oxides from metasomatic environments have high, but variable contents of Fe, Ca, Ti, Si and Th (around 10 wt.%), Th being low. (c) U-oxides crystallised during metamorphism contain minor impurities of the above listed elements (total of oxides < 2 wt.%). (d) Redistributed U-oxides have elevated amounts of these elements. (e) Unit-cell dimensions of U-oxides tend to reflect a complex function of formation temperature, oxidation grade and the influence of incorporated elements caused by their radius and electro-negativity. (f) A global negative correlation of unit-cell dimension and oxidation grade of uranium oxides is indicated but based on widely varying ratios of the two parameters. (g) Colloform U-oxide (pitchblende) is characterised by elevated Ca-contents (1-5 wt.% CaO) and an almost complete lack of Th (< 1 wt.% ThO2). (h) Idiomorphic U-oxide (uraninite) is commonly low in Ca (< 1.5 wt.% CaO) but contains relatively high Th values. (i) The reflectance of U-oxides generally correlates positively with Vickers hardness and unit-cell dimension, but the incorporation of other elements in the lattice of U-oxides may cause strong interference. (author)

  8. Compacting and crystallisation of transparent conductive oxidic sol-gel layers as illustrated by the example of zinc oxide; Verdichtung und Kristallisation von transparenten leitfaehigen oxidischen Sol-gel-Schichten am Beispiel des Zinkoxids

    Energy Technology Data Exchange (ETDEWEB)

    Schuler, T.

    2003-07-01

    It is shown that doped zinc oxide films on glass can be obtained by a low-cost sol-gel dip coating process. The lowest possible specific resistance is 1.1x10{sup -3}ohmcm for multiple layers of aluminium-doped zinc oxide. It was shown that for thick layers the crystallite size depends on the doping of the sol, the temperature and the sintering time while the film thickness is largely defined by the concentration (viscosity) of the solution and the drawing time. On this basis, a model of the observed structures was obtained which is also applicable to other sol-gel layers. Using the process parameter p of the equation ESD = p x IKG, the morphology of multiple layers can thus be defined. The structural change from a grain structure to a layered structure was at p = 2.4 to 3 and the transition from layer structure to columnar structure at p = 1. A comparison with spray pyrolysis showed that the suggested model is also suitable as a prototype model for film growth and may possibly applied to physical coating technologies as well. The observed morphology affects the electric and optical properties of the layers, as a result of grain boundaries and compacting. With increasing compacting, the specific resistance of the layer will get lower. It was demonstrated that the coating temperature can be reduced from 550 deg C to 450 deg C without impairing conductivity by reducing the thickness of individual films. Further, possibilities were shown of improving film characteristics or reducing process time by means of other sinter technologies, e.g. pyrolytic gas flame sintering and laser sintering. The biggest problem of sol-gel coating was the segregation of dopands. For all systems, it is assumed that the dopands not converted into (optical) charge carriers will segregate on the surfaces of the crystallites and may even agglomerate into X-ray amorphous oxidic phases if dopand concentrations are high enough. In any case, potential barriers will result which slow down current

  9. Radiation Response of Rhombohedral Oxides

    International Nuclear Information System (INIS)

    Devanathan, R.; Weber, W.J.; Mitchell, J.N.; Sickafus, K.E.; Nastasi, M.

    1997-05-01

    The radiation response of three rhombohedral oxides, namely, sapphire (α-Al 2 O 3 ), ilmenite (FeTiO 3 ), and geikielite (MgTiO 3 ), has been examined by irradiating electron transparent samples with 1 MeV Kr(+) and 1.5 MeV Xe(+)ions. The microstructural changes during irradiation were observed in situ in a high-voltage electron microscope using electron diffraction and microscopy. The irradiation conditions were designed to minimize beam heating and chemical effects due to the implanted ion. Of the three oxides studied, ilmenite is the most susceptible to radiation-induced amorphization while sapphire is the least susceptible. In all three materials, the critical temperature for amorphization was below 300 K indicating good room temperature resistance to amorphization by energetic beams

  10. Durability of Solid Oxide Cells

    DEFF Research Database (Denmark)

    Knibbe, Ruth; Hauch, Anne; Hjelm, Johan

    2011-01-01

    In recent years extended focus has been placed on monitoring and understanding degradation mechanisms in both solid oxide fuel cells and solid oxide electrolysis cells. The time-consuming nature of degradation experiments and the disparate conclusions from experiment reproductions indicates...... that not all degradation mechanisms are fully understood. Traditionally, cell degradation has been attributed to the materials, processing and cell operating conditions. More recently, focus has been placed on the effect of raw material and gas impurities and their long-term effect on cell degradation. Minor...... impurities have been found to play a significant role in degradation and in some cases can overshadow the cell operation condition related degradation phenomenon. In this review, several degradation diagnostic tools are discussed, a benchmark for a desirable degradation rate is proposed and degradation...

  11. Supercritical Water Oxidation Program (SCWOP)

    International Nuclear Information System (INIS)

    1994-02-01

    Purpose of SCWOP is to develop and demonstrate supercritical water oxidation as a viable technology for treating DOE hazardous and mixed wastes and to coordinate SCWO research, development, demonstration, testing, and evaluation activities. The process involves bringing together organic waste, water, and an oxidant (air, O 2 , etc.) to temperatures and pressures above water's critical point (374 C, 22.1 MPa); organic destruction is >99.99% efficient, and the resulting effluents (mostly water, CO 2 ) are relatively benign. Pilot-scale (300--500 gallons/day) SCWO units are to be constructed and demonstrated. Two phases will be conducted: hazardous waste pilot plant demonstration and mixed waste pilot demonstration. Contacts for further information and for getting involved are given

  12. Thermal expansion of beryllium oxide

    International Nuclear Information System (INIS)

    Solodukhin, A.V.; Kruzhalov, A.V.; Mazurenko, V.G.; Maslov, V.A.; Medvedev, V.A.; Polupanova, T.I.

    1987-01-01

    Precise measurements of temperature dependence of the coefficient of linear expansion in the 22-320 K temperature range on beryllium oxide monocrystals are conducted. A model of thermal expansion is suggested; the range of temperature dependence minimum of the coefficient of thermal expansion is well described within the frames of this model. The results of the experiment may be used for investigation of thermal stresses in crystals

  13. Functionality of the iron oxides

    International Nuclear Information System (INIS)

    Castano, J.G.; Arroyave, C.

    1998-01-01

    Some iron oxides have a great scientific and technological possibilities, not only for their importance in the present, but also for their great potential in the development of the future technologies. They have adequate properties to carry out several functions. They are plentiful in the nature and their synthetic obtention is not complex. This paper shows five of them (hematite, magnetite, maghemite, goethite and akaganeite) and their utilization in fields like chemical industry, biotechnology medicine, new materials and electromagnetism. (Author) 77 refs

  14. 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...... higher hydrogen sulfide uptake followed by oxidation catalyzed by iron-containing enzymes such as cytochrome c oxidase in a process uncoupled from energy conservation....

  15. 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...... higher hydrogen sulfide uptake followed by oxidation catalyzed by iron-containing enzymes such as cytochrome c oxidase in a process uncoupled from energy conservation....

  16. P -type transparent conducting oxides

    International Nuclear Information System (INIS)

    Zhang, Kelvin H L; Xi, Kai; Blamire, Mark G; Egdell, Russell G

    2016-01-01

    Transparent conducting oxides constitute a unique class of materials combining properties of electrical conductivity and optical transparency in a single material. They are needed for a wide range of applications including solar cells, flat panel displays, touch screens, light emitting diodes and transparent electronics. Most of the commercially available TCOs are n -type, such as Sn doped In 2 O 3 , Al doped ZnO, and F doped SnO 2 . However, the development of efficient p -type TCOs remains an outstanding challenge. This challenge is thought to be due to the localized nature of the O 2 p derived valence band which leads to difficulty in introducing shallow acceptors and large hole effective masses. In 1997 Hosono and co-workers (1997 Nature 389 939) proposed the concept of ‘chemical modulation of the valence band’ to mitigate this problem using hybridization of O 2 p orbitals with close-shell Cu 3 d 10 orbitals. This work has sparked tremendous interest in designing p -TCO materials together with deep understanding the underlying materials physics. In this article, we will provide a comprehensive review on traditional and recently emergent p -TCOs, including Cu + -based delafossites, layered oxychalcogenides, nd 6 spinel oxides, Cr 3+ -based oxides (3 d 3 ) and post-transition metal oxides with lone pair state (ns 2 ). We will focus our discussions on the basic materials physics of these materials in terms of electronic structures, doping and defect properties for p -type conductivity and optical properties. Device applications based on p -TCOs for transparent p – n junctions will also be briefly discussed. (topical review)

  17. Nanoparticular metal oxide/anatase catalysts

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention concerns a method of preparation of nanoparticular metal oxide catalysts having a narrow particle size distribution. In particular, the invention concerns preparation of nanoparticular metal oxide catalyst precursors comprising combustible crystallization seeds upon which...... the catalyst metai oxide is co-precipitated with the carrier metal oxide, which crystallization seeds are removed by combustion in a final calcining step. The present invention also concerns processes wherein the nanoparticular metal oxide catalysts of the invention are used, such as SCR (deNOx) reactions...

  18. Radiation induced lipid oxidation in fish

    International Nuclear Information System (INIS)

    Snauwaert, F.; Tobback, P.; Maes, E.; Thyssen, J.

    1977-01-01

    Oxidative rancidity in herring and redfish was studied as a function of the applied irradiation dose, the storage time and storage temperature and the packaging conditions. - Measurements of the TBA (thiobarbituric acid) value and the peroxide value were used to evaluate the degree of oxidation of lipids, and were related with sensory scores. - Especially for the fatty fish species (herring) irradiation accelerated lipid oxidation and induced oxidative rancidity. Irradiation of vacuum-packed herring fillets and subsequent storage at +2 C seems to be an interesting process. For the experiments conducted on a semi-fatty fish (redfish), oxidative rancidity was never the limiting factor for organoleptic acceptability. (orig.) [de

  19. Hypoxia, Oxidative Stress and Fat

    Directory of Open Access Journals (Sweden)

    Nikolaus Netzer

    2015-06-01

    Full Text Available Metabolic disturbances in white adipose tissue in obese individuals contribute to the pathogenesis of insulin resistance and the development of type 2 diabetes mellitus. Impaired insulin action in adipocytes is associated with elevated lipolysis and increased free fatty acids leading to ectopic fat deposition in liver and skeletal muscle. Chronic adipose tissue hypoxia has been suggested to be part of pathomechanisms causing dysfunction of adipocytes. Hypoxia can provoke oxidative stress in human and animal adipocytes and reduce the production of beneficial adipokines, such as adiponectin. However, time-dose responses to hypoxia relativize the effects of hypoxic stress. Long-term exposure of fat cells to hypoxia can lead to the production of beneficial substances such as leptin. Knowledge of time-dose responses of hypoxia on white adipose tissue and the time course of generation of oxidative stress in adipocytes is still scarce. This paper reviews the potential links between adipose tissue hypoxia, oxidative stress, mitochondrial dysfunction, and low-grade inflammation caused by adipocyte hypertrophy, macrophage infiltration and production of inflammatory mediators.

  20. Electrochemical oxidation of organic waste

    International Nuclear Information System (INIS)

    Almon, A.C.; Buchanan, B.R.

    1990-01-01

    Both silver catalyzed and direct electrochemical oxidation of organic species are examined in analytical detail. This paper describes the mechanisms, reaction rates, products, intermediates, capabilities, limitations, and optimal reaction conditions of the electrochemical destruction of organic waste. A small bench-top electrocell being tested for the treatment of small quantities of laboratory waste is described. The 200-mL electrochemical cell used has a processing capacity of 50 mL per day, and can treat both radioactive and nonradioactive waste. In the silver catalyzed process, Ag(I) is electrochemically oxidized to Ag(II), which attacks organic species such as tributylphosphate (TBP), tetraphenylborate (TPB), and benzene. In direct electrochemical oxidation, the organic species are destroyed at the surface of the working electrode without the use of silver as an electron transfer agent. This paper focuses on the destruction of tributylphosphate (TBP), although several organic species have been destroyed using this process. The organic species are converted to carbon dioxide, water, and inorganic acids