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  1. Sprachvermittlung und Spracherwerb in Afrika. Deutsch nach ...

    African Journals Online (AJOL)

    erlernende Fremdsprache richtig und auf hohem Niveau sprechen zu lernen. Lehrende sollten alles daransetzen zu verhindern, dass die Lernenden in dieser Vereinfachungsphase stehen bleiben und ihre Sprache fossilieren. Die Bewusstmachung der Ähnlichkeiten von Zulu und. Deutsch kann dazu beitragen, indem man ...

  2. Zwischenberichterstattung nach Börsenrecht, DRS, IAS und US-GAAP

    OpenAIRE

    Alvarez von Zerboni di Sposetti, Manuel

    2003-01-01

    Zwischenberichterstattung nach Börsenrecht, DRS, IAS und US-GAAP / von Manuel Alvarez und Stefan Wotschofsky. - 2., neubearb. und erw. Aufl. - Berlin : Erich Schmidt, 2003. - XX, 219 S. [1. Aufl. 2000

  3. Folgebewertung im vorratsvermögen - Fallstudie zur Vorgehensweise nach IFSR und HGB

    DEFF Research Database (Denmark)

    Quick, Reiner; Warming-Rasmussen, Bent

    2013-01-01

    über die wichstigsten Normen zur Folgebeweriung nach IFSR und HGB sowie zu deren Auslegung. Es schliessen sich ein Fallbeispiel und ein Vorschlag zu dessen Lösung an, in dessen Mittelpunkt sinkende Zeitwerte, die Frage des für die Folgebewerunng relevanten Markts und das Zuschreibungsgebot stehen....

  4. Metatheoriebildung in der dialogischen Konfliktbearbeitung – ein konzeptioneller Vorschlag am Beispiel der Konflikttransformation nach Galtung und des Konfliktmanagements nach Glasl und des Integralen Ansatzes nach Wilber

    Directory of Open Access Journals (Sweden)

    Karim Fathi

    2010-07-01

    really integrated Peace and Conflict Researcher should be familiar with epistemological and heuristic contexts, but also metatheoretical and theoretical contexts as well. Abstract - Deutsch Angesichts immer komplexerer Konflikte in der Friedens- und Konfliktforschung (Friedens- und Konfliktforschung sind Metatheorien von Nöten, die diese unübersichtliche Vielfalt unterschiedlicher Methoden zu integrieren vermögen. Im Rahmen des vorliegenden Papers soll hierzu ein konzeptioneller Vorschlag skizziert werden, indem zwei holistische und bekannte Ansätze der mediativen Konfliktbearbeitung in einem integrativen Kontext diskutiert werden:- Der Konfliktmanagement-Ansatz nach Prof. Dr. Friedrich Glasl (2004.- Die Transcend-Methode nach Prof. Dr. Johan Galtung (2000. Den theoretischen Rahmen, auf den sich die Überlegungen dieser Arbeit stützen, liefert der Integrale Ansatz (IA von Ken Wilber (2001 – eine viel diskutierte philosophische „Theorie von Allem“, die im Rahmen der Friedens- und Konfliktforschung jedoch noch weitgehend unberücksichtigt geblieben ist. Daher ist es im Rahmen der Arbeit von weiterem Interesse den IA auf seinen Mehrwert für eine integrierte Friedens- und Konfliktforschung zu untersuchen.Die Untersuchung verlief wie folgt: 1. Vorstellung der in der Untersuchung berücksichtigten Ansätze: a. Der Konfliktmanagement-Ansatz von Glasl unterscheidet eine Vielzahl von Kategorien und Ansatzmomenten, die ein komplexes Interventionsspektrum ergeben. Sehr wichtig ist hierbei unter anderem die Berücksichtigung von Eskalationsstufen, die eine Unterscheidung zwischen perzeptions- (niedrige Eskalation, gefühls- (mittlere Eskalation und verhaltensorientierten (hohe Eskalation Maßnahmen ermöglichen. b. Die Konflikttransformation nach Galtung zeichnet sich unter anderem durch dreigeteilte Schematisierungen aus, die ein komplexes Verständnis von Gewalt (direkt, kulturell, strukturell, Konflikt (Verhalten, Annahmen, Widerspruch und Frieden (Gewaltlosigkeit

  5. Postoperative Verlaufskontrollen beim Ulcus cruris nach Shave-Operation und Hauttransplantation

    OpenAIRE

    Pantelaki, Ioanna

    2016-01-01

    \\(\\bf Hintergrund:\\) Die Arbeit hat das Ziel die Shave-Operation mit Meshgraft-Deckung hinsichtlich der Einheilungsrate und der Schmerzreduktion zu untersuchen. \\(\\bf Methoden:\\) 56 Patienten mit einem Ulcus cruris unterzogen sich dem genannten Eingriff. Vor und 6 Monate nach der Operation wurden die Ulkusgröße, die bakterielle Besiedlung und die Schmerzintensität analysiert. \\(\\bf Ergebnis:\\) Bei 42,86% der Patienten konnte eine Abheilung erreicht werden, wobei die Ergebnisse hoch sign...

  6. Narrative Expositionstherapie (NET) für Menschen nach Gewalt und Flucht : Ein Einblick in das Verfahren

    OpenAIRE

    Schauer, Maggie; Elbert, Thomas; Neuner, Frank

    2017-01-01

    Die Narrative Expositionstherapie (NET) ist ein effizientes Kernelement der Behandlung von Kindern und Erwachsenen, die unter den Folgen von Mehrfach- und Komplextraumatisierung nach Gewalt und Flucht leiden. Die chronologische Erarbeitung einer Narration, der individuellen Lebensgeschichte in der NET ermöglicht Traumaüberlebenden eine Gesamtschau ihres Lebens und so die Integration der Lebenserfahrungen in den biografischen Zusammenhang. Sie aktiviert Ressourcen und erlaubt korrigierende Bez...

  7. Morphologische Veränderung des Beckenbodens und klinisches Outcome nach Resektionsrektopexie bei Beckenbodeninsuffizienz : Eine explorative, deskriptive Studie anhand der dynamischen Beckenboden-MRT

    OpenAIRE

    Busse, Anika

    2013-01-01

    Der Beckenboden und insbesondere die Beckenbodeninsuffizienz mit ihren Folgeerkrankungen wie anale Inkontinenz und Obstipationen sind nach wie vor ein Tabuthema. Aufgrund der steigenden Prävalenz, der damit verbundenen steigenden Kosten für das Gesundheitssystem und aufgrund der deutlichen Beeinflussung der Lebensqualität ist es wichtig effektive diagnostische Möglichkeiten und Therapien zu besitzen. Ziel dieser vorliegenden Studie sollte es somit sein das Outcome nach Resektionsrektopexie be...

  8. Quantenfische die Stringtheorie und die Suche nach Weltformel

    CERN Document Server

    Lüst, Dieter

    2011-01-01

    Lässt sich das Verhalten aller Dinge, von den kleinsten Teilchen bis zum Universum, einheitlich beschreiben? Der heißeste Kandidat für die Entwicklung einer Weltformel, die alle physikalischen Phänomene erklären kann, ist die Stringtheorie. Sollte sie sich als richtig erweisen, so würde das unser Verständnis über den Ursprung der Naturgesetze dramatisch verändern. Denn das von uns beobachtete Universum wäre dann vermutlich eine winzige Blase in einem viel größeren Gebilde, dem Multiversum. Um die Stringtheorie und die Idee des Multiversums plausibel zu machen, greift der international bekannte theoretische Physiker Dieter Lüst auf ein Modell zurück: das Leben von Fischen in einem Teich. Eines Tages gelingt es den Fischen, die kleinsten Teilchen zu identifizieren, aus denen alles im Fischteich besteht - eingeschlossen sie selbst. Sie nennen diese Urbausteine Quantenfische, da ihr Verhalten nahelegt, dass sie auch eine Art von Lebewesen sind. Doch der ersten folgt eine weitere Entdeckung der Fisch...

  9. Imaging before and after uterine artery embolization; Bildgebende Diagnostik vor und nach Uterusmyomembolisation

    Energy Technology Data Exchange (ETDEWEB)

    Kroencke, T.J. [Charite - Universitaetsmedizin Berlin, Radiologische Klinik, Campus Virchow-Klinikum, Berlin (Germany)

    2008-07-15

    Percutaneous catheter-based embolization treatment of symptomatic uterine fibroids has evolved into the most widely used alternative therapeutic approach to surgical treatment worldwide. Uterine artery embolization (UAE) induces infarction of leiomyomas, resulting in ischemic necrosis, hyaline degeneration, and size reduction with resolution of associated symptoms. Published experience suggests that UAE is an effective and reliable option for treating uterine fibroids with high patient satisfaction. Magnetic resonance imaging (MRI) is superior to ultrasonography for determining the site, size and number of fibroids, which is important for establishing the indication for UAE. Other potential advantages of MRI include the option of performing MR angiography (MRA) and obtaining contrast-enhanced images for monitoring the outcome of UAE and assessing possible complications after UAE. (orig.) [German] Die perkutane kathetergestuetzte Uterusmyomembolisation ist inzwischen weltweit die am meisten verbreitete Alternative zur operativen Behandlung des symptomatischen Uterus myomatosus. Der durch Embolisation der Aa. uterinae (Syn. Uterusarterienembolisation, UAE) bewirkte 'Myominfarkt' fuehrt zu ischaemischer Nekrose, hyalinem Umbau und Groessenreduktion der Myome unter Rueckbildung myomassoziierter Beschwerden. Die bisher publizierten Erfahrungen zeigen, dass es sich bei der Embolisation um eine effektive und sichere Methode mit hoher Patientinnenzufriedenheit handelt. Die Magnetresonanztomographie (MRT) ist dem Ultraschall in der fuer die Indikationsstellung wichtigen Beurteilung von Lage, Groesse und Zahl der Myomknoten ueberlegen. Weitere moegliche Vorteile ergeben sich durch den Einsatz der MR-Angiographie (MRA) sowie kontrastmittelunterstuetzter Aufnahmen zur Erfolgskontrolle und Abklaerung von Komplikationen nach Embolisation. (orig.)

  10. Endovascular brachytherapy to prevent restenosis after angioplasty; Endovaskulaere Brachytherapie in der Restenoseprophylaxe nach Angioplastie und Stentimplantation: Eine Uebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, W.A.; Bohndorf, K. [Klinikum Augsburg (Germany). Klinik fuer Diagnostische Radiologie und Neuroradiologie

    2003-02-01

    Endovascular radiotherapy is the first effective prophylaxis of restenosis after percutaneous transluminal angioplasty (PTA) and stenting. The FDA recently approved two devices for the delivery of intracoronary radiation following coronary artery stenting. Published multicenter, double-blind, randomized trials of intracoronary radiation therapy report good results for preventing in-stent restenosis, while the data for the peripheral circulation are still inconclusive. Beta-emitters are easier applicable and probably also safer, whereas gamma-emitters have been more extensively evaluated clinically so far. Primary indication for endovascular brachytherapy are patients at high risk for restenosis, such as previous restenoses, in-stent hyperplasia, long stented segment, long PTA lesion, narrow residual vascular lumen and diabetes. Data from coronary circulation suggest a safety margin of at least 4 to 10 mm at both ends of the angioplastic segment to avoid edge restenosis. To prevent late thrombosis of the treated coronary segment, antiplatelet therapy with clopidogrel and aspirin are recommended for at least 6 months after PTA and for 12 months after a newly implanted stent. An established medication regimen after radiotherapy of peripheral arteries is still lacking. (orig.) [German] Die endovaskulaere Radiotherapie stellt das erste erfolgreiche Therapiekonzept in der Restenoseprophylaxe nach PTA und Stentimplantation dar. Am 3.11.2000 hat die amerikanische Food and Drug Administration erstmalig zwei Brachytherapiegeraete zur Restenoseprophylaxe nach Koronararterien-Stenting zugelassen. Grosse multizentrische, kontrollierte Studien wurden fuer das koronare Stromgebiet mit positiven Ergebnissen publiziert, die Datenlage im peripheren Stromgebiet ist noch ungenuegend. Beta-Strahler bieten Vorteile in der Anwendung, moeglicherweise auch in der Sicherheit, Gamma-Strahler dagegen sind besser klinisch evaluiert. Die primaere Indikation zur endovaskulaeren Brachytherapie

  11. Information to go: Kommunikation im Prozess der Migration am Beispiel syrischer und irakischer Flüchtlinge auf ihrem Weg nach Deutschland

    Directory of Open Access Journals (Sweden)

    Anke Fiedler

    2016-07-01

    Full Text Available Vor dem Hintergrund der Flüchtlingsdebatte in Deutschland 2015 wird in diesem Beitrag danach gefragt, welche (Massen-Kommunikationskanäle Flüchtlinge vor, während und nach der Flucht nutzen, um sich über migrationsrelevante Themen zu informieren und sich darüber mit anderen Migrationswilligen auszutauschen. Dabei wird nicht nur die Frage nach der subjektiven Bewertung der genutzten Quellen gestellt, sondern auch untersucht, ob die Flüchtlinge eine informierte Entscheidung in den verschiedenen Phasen der Migration treffen. Auf Basis des Uses-and-Gratifications-Ansatzes und der Handlungstheorie (symbolischer Interaktionismus wurden zwischen November 2015 und Februar 2016 vier Fokusgruppen und 36 Tiefeninterviews mit syrischen und irakischen Flüchtlingen durchgeführt. Die Ergebnisse verdeutlichen, dass sich die befragten Flüchtlinge vor und während der Flucht gut informiert fühlten, da persönliche Kontakte und soziale Medien die Informationsbedürfnisse weitgehend befriedigen konnten. Informationsdefizite zeigten sich vor allem nach der Ankunft in Deutschland.

  12. Radiologic assessment of the outcome of Keller and Brandes arthroplasty for hallux rigidus; Hallux rigidus operiert nach Keller und Brandes: Radiologische Erfolgs- und Prognoseparameter

    Energy Technology Data Exchange (ETDEWEB)

    Breitenseher, M.J. [Abt. fuer Osteologie, Universitaetsklinik fueer Radiodiagnostik und Besondere Klinische Einrichtung Magnet Resonanz, Wien (Austria)]|[Ludwig-Boltzmann-Institut fuer Radiologische Tumordiagnostik, Wien (Austria); Toma, C.D. [Universitaetsklinik fuer Orthopaedie, Wien (Austria); Gottsauner-Wolf, F. [Universitaetsklinik fuer Orthopaedie, Wien (Austria); Imhof, H. [Abt. fuer Osteologie, Universitaetsklinik fueer Radiodiagnostik und Besondere Klinische Einrichtung Magnet Resonanz, Wien (Austria)]|[Ludwig-Boltzmann-Institut fuer Radiologische Tumordiagnostik, Wien (Austria)

    1996-06-01

    The aim of this study was to evaluate the pre- and postoperative radiographic findings of hallux rigidus treated with Keller and Brandes arthroplasty to determine the radiographic outcome and to identify a prognostic marker. 83 patients with a total of 121 cases of hallux rigidus operated using Keller and Brandes arthroplasty were followed up (mean 9.7 y). A comparison of the pre- and postoperative radiographs, the clinical and subjective findings was predicated on a five point scale: 1. Percentage of proximal phalanx resected (<33%, 33-50%, >50%), 2. joint space, 3. ratio of the length of the first and second metatarsals, 4. first intermetatarsal angle, and 5. hallux valgus angle. In the patient group which had 33-50% of the proximal phalanx excised (n=67. 55%) the highest patient satisfaction was observed (96%). If resection of the proximal phalanx exceeded 50% (n=13. 11%), non physiologic dorsiflexion of the toe occurred and patients were unsatisfied (62%). Excision of less than 33% of the hallux (n=41. 34%) was associated with a recurrent hallux rigidus. No other evaluated radiological parameter proved to be of significance. The most important radiological parameter in the evaluation of the outcome of Keller and Brandes arthroplasty as the percentage of the proximal phalanx which had ben excised. (orig.) [Deutsch] Ziel der Studie war es, auf prae- und postoperativen Roentgenbildern des Hallux rigidus radiologische Parameter zu ermitteln, die den Erfolg der Arthroplastik nach Keller und Brandes abschaetzen und von prognostischer Relevanz sind. 121 Hallux-rigidus-Operationen bei 83 Patienten wurden nachuntersucht (9,7 a). 5 Kriterien wurden an den prae- und postoperativen Roentgenbildern ausgewertet: 1. Anteil der Grosszehengrundgliedresektion in Prozent (<33%, 33-50%, >50%), 2. Gelenkspaltbreite, 3. Laengenverhaeltnis von erstem und zweitem Metartasalknochen, 4. erster Intermetatarsalwinkel und 5. Hallux-valgus-Winkel und mit den klinischen Ergebnissen

  13. Feministische Gesellschaftstheorie und die Suche nach der Anschlussfähigkeit Feminist Social Theory in Search of Connections

    Directory of Open Access Journals (Sweden)

    Silke Schneider

    2002-07-01

    Full Text Available Der Sammelband „Soziale Verortung der Geschlechter“ stellt einen Querschnitt aktueller feministischer Theoriediskussionen vor. Dass bei der Suche nach angemessenen gesellschaftsanalytischen Kategorien sowohl die Klassiker/-innen der Politischen Theorie und Gesellschaftstheorie wie auch ihre Epigonen mannigfache Kritik-, aber auch vielversprechende Anschlußpunkte zu bieten haben, vermögen alle Beiträge zu vermitteln. Somit bietet der Band mit seiner breit angelegten Konzeption, die wichtige und durchaus gegensätzliche Theorien verbindet, einen guten Überblick und regt gleichzeitig zur vertiefenden Lektüre an. Bemerkenswert ist, dass nahezu alle Beiträge für eine Verbindung von Empirie und Theorie plädieren und hierbei die Einbeziehung einer historischen Perspektive als grundlegend und unabdingbar für eine Analyse der Geschlechterverhältnisse als Teil gesellschaftlicher Entwicklung erachtet wird.The anthology “The Social Positionings of Gender” presents a cross section of current debates in feminist theory. The authors show how authors of classical political and social theory as well as their successors offer plenty of room for criticism, but also promising starting points in the search for appropriate socio-analytic categories. This anthology not only offers a good overview over current theory by connecting different (and at times contradicting schools of thought, but also inspires to engage in further reading on these issues. What is particularly remarkable about this work is that almost all of the contributions plead for a combination of empirical research and theoretical work, as they consider the inclusion of a historical perspective as fundamental and indispensable for an analysis of gender relations as part of societal developments.

  14. DNA-Methylierung nach abiotischen und biotischen Einflüssen und Expressionsanalyse pathogeninduzierter Gene in Picea abies (L.) Karst.

    OpenAIRE

    Baumann, Ruediger

    2006-01-01

    Basierend auf Beobachtungen über phänotypische Änderungen in Vollgeschwisterfamilien der Fichte,Picea abies, aus unterschiedlichen Kreuzungsumwelten wurde nach der geneti-schen Untersuchung mit EST-Markern eine kapillarelektrophoretische Untersuchung der DNA durchgeführt. Dabei wurden signifikante Unterschiede im Methylcytosin(mC)-Gehalt festgestellt. Messungen der mC-Gehalte nach Hitzeschock zeigten, den Einfluss der Um-weltbedingungen auf die Methylierung der DNA. Untersuchungen zur Dynamik...

  15. Verwendung von Kabeln und isolierten Leitungen für Fernmeldeanlagen und Informationsverarbeitungsanlagen; Besondere Richtlinien für Leitungen mit Litzenleitern für erhöhte mechanische Beanspruchung für Fernmeldeanlagen und Informationsverarbeitungsanlagen nach DIN 57817/VDE 0817 [VDE-Richtlinie

    CERN Document Server

    Deutsches Institut für Normung. Berlin

    1984-01-01

    Verwendung von Kabeln und isolierten Leitungen für Fernmeldeanlagen und Informationsverarbeitungsanlagen; Besondere Richtlinien für Leitungen mit Litzenleitern für erhöhte mechanische Beanspruchung für Fernmeldeanlagen und Informationsverarbeitungsanlagen nach DIN 57817/VDE 0817 [VDE-Richtlinie

  16. Avascular bone necrosis: MR imaging findings before and after core decompression; MR-Tomographie avaskulaerer Knochennekrosen: Primaerbefunde und Verlaufsbeobachtungen nach Markraumdekompression

    Energy Technology Data Exchange (ETDEWEB)

    Adam, G [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Keulers, P [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Forst, J [Technische Hochschule Aachen (Germany). Klinik fuer Orthopaedie; Neuerburg, J [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Kilbinger, M [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Guenther, R W [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik

    1995-10-01

    17 patients with avascular epiphyseal necrosis were examined by MRI using T{sub 1}-weighted spin echo sequences before and after gadopentetate dimeglumine application, T{sub 2}-weighted spin echo sequences and in some patients with fat-saturated 2D gradient echo sequences up to 22 months after core decompression. All patients but one recovered from symptoms after core decompression. Although the signal morphology of the necrotic area remained unchanged in the majority of the cases, a decrease of the joint effusion was observed as well as an ongoing signal increase after gadopentetate dimeglumine application. The last examinations displayed similar signal characteristics as on the preoperative scans; however, a reduction of the necrotic zone became evident. (orig./MG) [Deutsch] 17 Patienten mit avaskulaerer Epiphysennekrose wurden mit T{sub 1}-gewichteten Spin-Echo-Sequenzen vor und nach Gadolinium-DTPA-Gabe, T{sub 2}-gewichteten Spin-Echo-Sequenzen und teilweise mit fettsupprimierten 2-D-Gradienten-Echo-Sequenzen bis zu 22 Monate nach Markraumdekompression untersucht. Mit einer Ausnahme waren alle Patienten nach dem Eingriff beschwerdefrei. Obwohl sich die Signalmorphologie zunaechst nicht oder wenig aenderte, konnte eine Abnahme des begleitenden Gelenkergusses bei weiterhin nachweisbarem Signalanstieg im Nekroseareal nach Kontrastmittelgabe beobachtet werden. Bei den letzten Untersuchungen nach Dekompression (bis zu 22 Monate) konnten zum Teil noch aehnliche Signalveraenderungen wie bei der Erstuntersuchung, jedoch keine Verkleinerung des Nekroseareals nachgewiesen werden. (orig./MG)

  17. Assessment of cognitive functions after prophylactic and therapeutic whole brain irradiation using neuropsychological testing; Erfassung kognitiver Funktionen nach prophylaktischer und therapeutischer Ganzhirnbestrahlung mittels neuropsychologischer Testverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Penitzka, S.; Wannenmacher, M. [Universitaetsklinikum Heidelberg (Germany). Abt. Klinische Radiologie; Steinvorth, S. [Universitaetsklinikum Heidelberg (Germany). Abt. Klinische Radiologie; MIT, Cambridge, MT (United States). Dept. of Brain and Cognitive Sciences; Sehlleier, S. [Universitaetsklinikum Heidelberg (Germany). Abt. Klinische Radiologie; Universitaetsklinikum Wuerzburg (Germany). Abt. Strahlentherapie; Fuss, M. [Universitaetsklinikum Heidelberg (Germany). Abt. Klinische Radiologie; Texas Univ., San Antonio, TX (United States). Health Science Center; Wenz, F. [Universitaetsklinikum Heidelberg (Germany). Abt. Klinische Radiologie; Universitaetsklinikum Mannheim (Germany). Sektion Radioonkologie

    2002-05-01

    Purpose: Aim of this study was the assessment of neuropsychological changes after whole brain irradiation. Patients and Method: 64 patients were tested before, and 29 after whole brain irradiation, including 28 patients with small cell lung cancer (SCLC) before prophylactic cranial irradiation (PCI) and 36 patients with cerebral metastases before therapeutic cranial irradiation (TCI), as well as 14 patients after PCI and 15 after TCI (Table 1). Intelligence, attention and memory were assessed applying a 90-minute test battery of standardized, neuropsychological tests (Table 3). Results: Patients with SCLC showed test results significantly below average before PCI (n=28, mean IQ=83, SD=17). Neither after PCI, nor after TCI the tested neuropsychological functions decreased significantly (Tables 4, 5). A comparison between SCLC-patients with and without cerebral metastases before whole brain irradiation showed better test-results in patients with cerebral metastases and fewer cycles of preceding chemotherapy (Table 7). Conclusion: Neuropsychological capacity in patients with SCLC was impaired even before PCI. Possible reason is the preceding chemotherapy. Whole brain irradiation did not induce a significant decline of cognitive functions in patients with PCI or TCI. A decline in a longer follow-up nevertheless seems possible. (orig.) [German] Zielsetzung: Ziel der Studie war die Erfassung moeglicher Veraenderungen der neuropsychologischen Leistungsfaehigkeit nach Ganzhirnbestrahlung. Patienten und Methode: Untersucht wurden 64 Patienten vor und 29 Patienten nach Ganzhirnbestrahlung. Es handelte sich um 28 Patienten mit kleinzelligem Bronchialkarzinom (SCLC) vor prophylaktischer Ganzhirnbestrahlung (PCI) und um 36 Patienten mit Hirnmetastasen vor therapeutischer Ganzhirnbestrahlung (TCI). Es wurden 14 Patienten nach PCI und 15 Patienten nach TCI getestet. Zur Anwendung kam eine 90-minuetige Testbatterie standardisierter, neuropsychologischer Testverfahren zur Messung

  18. Antisemitismus, Shoah und deutsche Verantwortung:(Nach)Wirkungen des Nationalsozialismus im medialen Nahostdiskurs

    OpenAIRE

    Ullrich, Peter

    2010-01-01

    Wahrscheinlich wird kein anderer internationaler Konflikt derart kontrovers und emotional in der bundesrepublikanischen Öffentlichkeit sowie auch und gerade in der politischen Linken diskutiert wie der israelisch-palästinensische oder weiter gefasst, der Nahost-Konflikt. Aus diesem Grund nimmt dieses Thema einen besonderen Platz in der Bildungsarbeit der Rosa-Luxemburg- Stiftung im Inland wie im Ausland ein. Wenngleich dabei auch in der Stiftung und ihrem Umfeld die Meinungen auseinandergehen...

  19. Was kommt nach dem Handel? Umnutzung von Einzelhandelsflächen und deren Beitrag zur Stadtentwicklung

    OpenAIRE

    Sperle, Tilman

    2012-01-01

    In der Stadt europäischen Typs sind Stadt und Handel eng miteinander verwoben. Die Bedeutung des Handels geht weit über dessen originäre Versorgungsfunktion hinaus. Für die städtischen Zentren und Nebenzentren übernimmt er sowohl gestaltende als auch soziale Funktionen und trägt mit seiner belebenden Wirkung maßgeblich zum urbanen Leben bei. Mit dem tief greifenden Strukturwandel im Einzelhandel verändert sich diese Beziehung zwischen Stadt und Handel dramatisch, Trading-down-Prozesse geh...

  20. Radiological findings, evaluation and treatment of patellofemoral pain after total knee arthroplasty; Radiologische Diagnostik, Beurteilung und Behandlung des patellofemoralen Schmerzes nach primaerer Knieendoprothetik

    Energy Technology Data Exchange (ETDEWEB)

    Springorum, H.R.; Keshmiri, A.; Heers, G.; Renkawitz, T.; Grifka, J.; Baier, C. [Asklepios Klinikum Bad Abbach, Orthopaedische Klinik fuer die Universitaet Regensburg, Bad Abbach (Germany)

    2012-11-15

    Total knee arthroplasty (TKA) is one of the most successful operative procedures over the last decades in orthopedic surgery; however, some patients suffer from pain, limited range of motion, instability, infections or other complications postoperatively. Patellofemoral pain (PFP) in particular is a common problem after TKA and often necessitates revision surgery. Mainly increasing and localized contact pressure and patella maltracking are held responsible for PFP but the reasons vary. Diagnostics and therapy of PFP is not easy to manage and should be treated following a clinical pathway. The authors suggest that patients with PFP should be categorized after basic diagnostic measures according to the suspected diagnosis: (1) tendinosis, (2) mechanical reasons, (3) intra-articular non-mechanical reasons and (4) neurogenic/psychiatric reasons. Efficient application of special diagnostic measures and further therapy is facilitated by this classification. (orig.) [German] Die endoprothetische Versorgung des Kniegelenks ist eine Operation mit hohem Zugewinn an Lebensqualitaet. Dennoch sind je nach Literaturstelle bis zu 50% der Patienten von Schmerzen, Bewegungseinschraenkung, Instabilitaet, Infektion oder anderen Komplikationen betroffen. Insbesondere der patellofemorale Schmerz (PFS) ist eine haeufige Komplikation nach primaerer Knieendoprothetik und wird je nach Literatur mit 1-50% der Faelle angegeben. Insbesondere der erhoehte retropatellare Anpressdruck und eine schlechte Fuehrung der Patella werden fuer den PFS verantwortlich gemacht, doch die Ursachen sind vielfaeltig. Diagnostik und Behandlung sind komplex und sollten strukturiert durchgefuehrt werden. Nach der Basisdiagnostik schlagen die Autoren daher eine Einteilung in eine der 4 Gruppen vor: (1) Tendinosen, (2) mechanische Probleme, (3) intraartikulaere nichtmechanische Probleme, (4) neurogene/psychische Probleme. Durch die Einteilung in diese verschiedenen Gruppen werden eine effiziente spezielle

  1. Steueroptimierte Alters- und Berufsunfähigkeitsvorsorge nach dem Alterseinkünftegesetz

    OpenAIRE

    Eberhardt, Michael G.

    2007-01-01

    Eine höhere Lebenserwartung bei gleichzeitiger Überalterung der deutschen Gesellschaft sind maßgebliche Gründe eines heute bereits festzustellenden Defizits der gesetzlichen Rentenversicherung. Die jüngste Rentenreform mit dem Altersvermögens- und Alterseinkünftegesetz setzte deshalb maßgebliche Anreize, die Alterssicherung eigenverantwortlich um eine private, staatlich geförderte Vorsorge zu ergänzen. Jedoch mangelt es derzeit vorwiegend an einer fachkundigen Informations- und Beratungsleist...

  2. [Annemarie Stiedl. Auf nach Wien! Die mobilität des mitteleuropäischen Handwerks im 18. und 19. Jahrhundert am Beispiel der Haupt- und Residenzstadt] / Raimo Pullat

    Index Scriptorium Estoniae

    Pullat, Raimo, 1935-

    2009-01-01

    Arvustus: Stiedl, Annemarie. Auf nach Wien! Die mobilität des mitteleuropäischen Handwerks im 18. und 19. Jahrhundert am Beispiel der Haupt- und Residenzstadt. Sozail- und wirtschaftshistorische Studien. Bd. 30. Wien, 2003. Teose põhisisu moodustab 18. ja 19. sajandi linnakäsitööliste rände ruumiliste muutuste ja nihete jälgimine. Autor on võtnud vaatluse alla peamiselt neli käsitööametit : lihunikud, korstnapühkijad, siidist asjakeste valmistajad ning nahast kottide ja mappide valmistajad

  3. MR imaging of the lateral collateral ligaments after ankle sprain; Aussenbandrupturen des Sprunggelenkes - Darstellung mit der MRT vor und nach funktioneller Therapie

    Energy Technology Data Exchange (ETDEWEB)

    Grebe, P. [Klinik fuer Radiologie der Universitaetsklinik, Mainz (Germany); Kreitner, K.F. [Klinik fuer Radiologie der Universitaetsklinik, Mainz (Germany); Roeder, W. [Abt. fuer Chirurgie, St-Hildegardis-Krankenhaus, Mainz (Germany); Kersjes, W. [Klinik fuer Radiologie der Universitaetsklinik, Mainz (Germany); Hennes, R. [Abt. fuer Allgemein- und Unfallchirurgie, St. Josefshospital, Wiesbaden (Germany); Runkel, M. [Unfallchirurgische Klinik der Unversitaetsklinik, Mainz (Germany)

    1995-09-01

    35 patients with ankle sprain were examined by MRI and stress radiographs. 13 were operated afterwards, 22 patients underwent a functional conservative therapy and were examined by MRI and stress radiographs and second time after three months. MRI reports were correct in 12 of 13 operated cases. After conservative therapy we did not find any disrupted ankle ligament. MRI showed intact ligaments thickened by scar. (orig./MG) [Deutsch] 35 Patienten mit klinischem Verdacht auf Aussenbandruptur wurden mit der MRT untersucht. 13 Patienten wurden operiert, 22 konzervativ therapiert. Letztere wurden nach drei Monaten erneut mit MRT und gehaltenen Aufnahmen untersucht. Die MRT-Befunde stimmten in 12 von 13 Faellen mit den operativ erhobenen Befunden ueberein. Nach dreimonatiger konzervativer Therapie waren alle 22 Sprunggelenke stabil. Die rupturierten Baender stellten sich verdickt und durchgaengig dar. (orig./MG)

  4. Das Konzept "Neue Soziale Bewegungen" nach Alain Touraine und die Grenzen seiner Anwendbarkeit in Guatemala

    OpenAIRE

    Kalny, Eva

    2012-01-01

    "Sowohl indigene Bewegungen als auch soziale Bewegungen gegen Großprojekte wie Staudämme, Minen und den Anbau von Palmöl und Zuckerrohr für die Gewinnung von Agrarsprit sind im Nachkriegsguatemala sehr aktiv. Dabei ist im letzten Jahrzehnt eine Verschiebung von identitären Forderungen hin zur vermehrten Verteidigung natürlicher Ressourcen beobachtbar. Der verstärkte Kampf um die Erhaltung des Lebensraums, der in ganz Lateinamerika zu beobachten ist, greift in Guatemala auf indigene Konzepte z...

  5. Massenmedien und Versöhnung: Die Berichterstattung über den deutsch-französischen Friedensprozeß nach dem 2. Weltkrieg

    Directory of Open Access Journals (Sweden)

    Susanne Jaeger

    2003-10-01

    Full Text Available Der vorliegende Beitrag beinhaltet die ersten Ergebnisse einer Langzeitstudie, bei der flächendeckend die deutsche Nachkriegsberichterstattung über Frankreich von 1946 bis 1970 inhaltsanalytisch ausgewertet wurde. Die Studie stützt sich dabei auf das Modell der Nachrichtenfaktoren von Johan Galtung, welche nach seiner Ansicht die Auswahl der Themen bestimmen, die zu einer Nachricht werden. Genau in diesen Selektionsroutinen liegt jedoch die implizite Gefahr, Konflikte zu vertiefen statt sie einzudämmen bzw. durch ein breites Verständnis der Hintergründe gewaltfrei bearbeitbar zu machen. Für die Zeit nach einem Krieg könnten sie Hindernisse auf dem Weg zur Annäherung und Aussöhnung ehemaliger Gegner darstellen. Wie jedoch sieht die Berichterstattung nach dem Krieg tatsächlich aus? Zeigen Massenmedien Bereitschaft zu einer veränderten Berichterstattung? Der Fall der französisch-deutschen Aussöhnung, welcher als Beispiel für einen gelungenen Aussöhnungsprozess gelten kann, belegt, dass Friedensprozesse von den Medien durchaus adäquat begleitet werden können: Z.B. ist der Anteil "positiver" Themen bzw. Berichterstattung konsistent höher als der "negativer", und der Anteil von Non-Elite-Themen steigt an und kündet von Interesse an französischer Lebensart und Kultur. Die Ergebnisse zeigen, dass Negativismus in den Medien kein Naturgesetz ist, sondern überwunden werden kann, wenn Frieden und Versöhnung auf der Tagesordnung stehen.

  6. Auf in die Zukunft! Was kommt nach der bücherlosen Bibliothek? Reflexionen und Wahrnehmungsunterschiede zur Rolle von öffentlichen Bibliotheken

    Directory of Open Access Journals (Sweden)

    Wolfgang Kaiser

    2014-03-01

    Full Text Available Die Sehnsucht nach papierlosen und digitalen Bibliotheken ist auch in Deutschland weit verbreitet. Dabei entsteht der Irrglaube, die alleinige digitale Ausrichtung der eigenen Bibliothek mache diese zukunftsfähig. Ökonomisierungstendenzen, ein Mangel an Handeln nach ethischen Prinzipien, die ständige Messung von Ausleihen und Kunden sind das Spiegelbild des gegenwärtigen ideologischen Zeitgeistes. Im Artikel werden vermeintliche Glücksversprechen entlarvt und Alternativen aufgezeigt. Es wird für eine Öffnung hin zu anderen verwandten Disziplinen und der Förderung von mehr Vielfalt in der Ausbildung von Bibliothekaren und Bibliothekarinnen plädiert. Alternative Hinweise und Anregungen, welche für eine Neubewertung öffentlicher Bibliotheken eintreten, sind Teil des folgenden Beitrags. The longing for paperless and digital libraries is also very widespread in Germany as well as in other countries. At the same time there’s the misconception that the digital orientation might be the silver bullet for their institutions for a sustainable future. Tendencies of economization, the steady measurement of growth in library loans, and the notion and perception of clients and customers in libraries are a mirror image of our current ideological Zeitgeist. The article unmasks assumed promises of digitalization. It illustrates alternatives for the implementation of more democratic and participatory library policies. Furthermore the author pleads for an opening to other disciplines and the promotion of more diversity within the library field. Alternative leads and suggestions, which advocate a different evaluation of public libraries, are part of the following article.

  7. Erzwingt die Quantenmechanik eine drastische Änderung unseres Weltbilds? Gedanken und Experimente nach Einstein, Podolsky und Rosen

    Science.gov (United States)

    Frodl, Peter

    Von den Anfängen der Quantenmechanik bis heute gibt es Versuche, sie als statistische Theorie über Ensembles individueller klassischer Systeme zu interpretieren. Die Bedingungen, unter denen Theorien verborgener Parameter zu deterministischen Beschreibungen dieser individuellen Systeme als klassisch angesehen werden können, wurden von Einstein, Podolsky und Rosen 1935 formuliert: 1. Physikalische Systeme sind im Prinzip separierbar. 2. Zu jeder physikalischen Größe, deren Wert man ohne Störung des betrachteten Systems mit Sicherheit voraussagen kann, existiert ein ihr entsprechendes Element der physikalischen Realität.Zusammen sind sie, wie Bell 1964 gezeigt hat, prinzipiell unverträglich mit der Quantenmechanik und unhaltbar angesichts neuerer Experimente. Diese erweisen einmal mehr die Quantenmechanik als richtige Theorie. Um ihre Ergebnisse zu verstehen, müssen wir entweder die in der klassischen Physik als selbstverständlich angesehene Annahme der Separierbarkeit physikalischer Systeme aufgeben oder unseren Begriff der physikalischen Realität revidieren. Eine Untersuchung des Begriffs der Separabilität und einige Überlegungen zum Problem der Messung von Observablen zeigen, daß eine Änderung des Begriffs der physikalischen Realität unumgänglich ist. Der revidierte Realitätsbegriff sollte mit klassischer Physik und Quantenmechanik verträglich sein, um ein einheitliches Weltbild zu ermöglichen.Translated AbstractDo Quantum Mechanics Force us to Drastically Change our View of the World? Thoughts and Experiments after Einstein, Podolsky and RosenSince the advent of quantum mechanics there have been attempts of its interpretation in terms of statistical theory concerning individual classical systems. The very conditions necessary to consider hidden variable theories describing these individual systems as classical had been pointed out by Einstein, Podolsky and Rosen in 1935: 1. Physical systems are in principle separable. 2. If it is possible to

  8. Verwendung von Kabeln und isolierten Leitungen für Fernmeldeanlagen und Informationsverarbeitungsanlagen; Besondere Richtlinie für selbsttragende Fernmelde-Luftkabel auf Starkstrom-Freileitungen über 1 kV nach DIN 57818/VDE 0818 [VDE-Richtlinie

    CERN Document Server

    Deutsches Institut für Normung. Berlin

    1983-01-01

    Verwendung von Kabeln und isolierten Leitungen für Fernmeldeanlagen und Informationsverarbeitungsanlagen; Besondere Richtlinie für selbsttragende Fernmelde-Luftkabel auf Starkstrom-Freileitungen über 1 kV nach DIN 57818/VDE 0818 [VDE-Richtlinie

  9. Die Rechtsstellung von Ausländern nach staatlichem Recht und Völkerrecht. Herausgegeben von Jochen Abr. Frowein und Torsten Stein. (Beiträge zum ausländischen öffentlichen Recht und Völkerrecht, Band 94) / Henn-Jüri Uibopuu

    Index Scriptorium Estoniae

    Uibopuu, Henn-Jüri, 1929-2012

    1988-01-01

    Raamatuarvustus: Die Rechtsstellung von Ausländern nach staatlichem Recht und Völkerrecht = The legal position of aliens in national and international law = Le régime juridique des étrangers en droit national et international / Max-Planck-Institut für ausländisches öffentliches Recht und Völkerrecht ; herausgegeben von Jochen A. Frowein, Torsten Stein. Berlin [etc.] : Springer, 1987

  10. Ecotoxicological and human toxicological risk assessment of PAH-contaminated soils before and after biological treatment; Oekotoxikologische und humantoxikologische Risikobewertung PAK-belasteter Boeden vor und nach biologischer Behandlung

    Energy Technology Data Exchange (ETDEWEB)

    Roos, P.H.; Hanstein, W.G. [Bochum Univ. (Germany). Inst. fuer Physiologische Chemie; Weissenfels, W.D. [RAG Umwelt Kommunal GmbH, Bottrop (Germany); Afferden, M. van [IMTA, Jiutepec, Mor. (Mexico); Pfeifer, F. [DMT-Gesellschaft fuer Forschung und Pruefung mbH, Essen (Germany)

    2000-07-01

    The goal of the present work is to assess the adverse effects of soil bound polycyclic aromatic hydrocarbons (PAH) which remain in soils after biological remediation. We focus on risk assessment for mammalian species with respect to the oral uptake of contaminated soil particles and compare the results of a biomarker test with those of an ecotoxicological assay, the bioluminescence inhibition test with Vibrio fischeri. As a biomarker effect in mammals, we determined the liver microsomal cytochrome P450 enzyme CYP1A1 which is induced by PAH in exposed rats. After biological soil treatment, different amounts of PAH remain in the soil depending on the soil properties and initial pollutant composition. Particularly, higher condensated PAH resists biological treatment due to its hydrophobicity. In addition, high amounts of organic carbon in the soils affect remediation efficiency. In the bioluminescence inhibition test, eluates of all biologically treated soils studied do not reveal any or only low inhibitory effects. In contrast, the oral uptake of biologically treated contaminated soils leads to induction levels for CYP1A1 similar to those in the untreated samples. A good correlation is obtained between CYP1A1 levels and the amount of 5 and 6-ring PAH in the soil samples. The main result is that the remediation efficiency determined by the luminescence test is not reflected by the biomarker test, a finding which indicates the high bioavailability of residual PAH in soils. Consequently, new criteria for human risk assessment can be delineated. (orig.) [German] Ziel dieser Arbeit ist es, moegliche toxische Wirkungen PAK-belasteter Boeden vor und nach biologischer Sanierung zu erfassen. Hierbei liegt der Schwerpunkt auf der Abschaetzung des Risikos fuer Saeugetiere nach oraler Aufnahme von Bodenpartikeln. Als Biomarker-Effekt fuer die PAK-Aufnahme haben wir in Ratten die Induktion des lebermikrosomalen P450-Enzyms CYP1A1 bestimmt, dessen Expression durch PAK moduliert

  11. Thyroid volume reduction following radioiodine therapy in patients with autonomous goitre and Graves` disease; Volumenreduktion der Schilddruese nach Radiojodtherapie bei Patienten mit Schilddruesenautonomie und Morbus Basedow

    Energy Technology Data Exchange (ETDEWEB)

    Dederichs, B. [Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany); Otte, R. [Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany); Klink, J.E. [Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany); Schicha, H. [Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)

    1996-10-01

    Aim: It is well known that radioiodine therapy (RITh) leads to a significant thyroid volume reduction (TVR). But until now only little data has been presented due to the course of time and the extent of TVR. Method: Therefore the data of 33 patients with Graves` disease (GD), 36 patients with multifocal (MAG) and 31 with solitary (SAG) autonomous goitre were analyzed retrospectively. Results: All the patients showed a highly significant (p<0.001) TVR, which continued up to 1 year after RITh. Receiving equal effective radiation doses, the extent of TVR was significantly greater for GD than for MAG. This difference developed within six weeks up to 3 months after RITh. Conclusion: This observation suggests that the underlying thyroid disease affects the therapeutic effect of RITh and may be partially explained by the total suppression of non-autonomous thyroid tissue in AG at the time of RITh. In patients with SAG with a 1.7 times higher effective radiation dose than in MAG relative TVR was about 1.6 times stronger in SAG than in MAG. This demonstrates a direct relation between the effective radiation dose and the extent of the TVR after RITh. (orig.) [Deutsch] Ziel: Es ist bekannt, dass die Radiojodtherapie (RJTh) zu einer relvanten Schilddruesenvolumenreduktion (SVR) fuehrt. Bisher wurden jedoch nur vereinzelt systematische Daten zum zeitlichen Verlauf und quantitativen Ausmass der SVR veroeffentlicht. Methode: Daher fuehrten wir eine retrospektive Auswertung der Daten von 33 Patienten mit Morbus Basedow (MB), 36 Patienten mit multifokaler (MFA) und 31 mit unifokaler (UFA) Autonomie der Schilddruese durch. Ergebnisse: Fuer alle Patientengruppen ergab sich eine hochsignifikante (p<0,001) SVR, welche sich bis ein Jahr nach RJTh signifikant fortsetzte. Obwohl die effektive Herddosis nicht signifikant verschieden war, war das Ausmass der SVR fuer Patienten mit MB signifikant groesser als fuer Patienten mit MFA. Dieser Unterschied war bereits innerhalb der ersten 6

  12. Beijing Bubble, Beijing Bust: Inequality, Trade, and Capital Inflow into China Beijing Blase, Beijing Krise: Ungleichheit, Handel und Kapitalzufluss nach China

    Directory of Open Access Journals (Sweden)

    James K. Galbraith

    2009-07-01

    Full Text Available This paper explores the relationships between inequality, trade, and capital flows into China since the early 1990s and particularly in the first years of the present decade. We show that the rise in economic inequality in China has more to do directly with the activities associated with China’s financial and building boom, notably in Beijing, than with the massive growth in manufacturing employment and in Chinese exports since China joined the WTO in 2001. Nevertheless, it is likely that a flow of profits from the export boom did feed the speculative fires in the capital and elsewhere, and therefore it should be no surprise that the fall of one should be linked to the fall of the other, in a particularly painful reduction of economic inequality. In diesem Artikel werden die Beziehungen zwischen Ungleichheit, Handel und Kapitalzufluss nach China seit den frühen 1990er Jahren untersucht. Es wird aufgezeigt, dass die steigende wirtschaftliche Ungleichheit in China weit mehr mit Chinas Finanz- und Bauboom insbesondere in Beijing zu tun hat als mit dem großen Anstieg der Beschäftigung in der Produktion und in Chinas Exporten seit dem WTO-Beitritt im Jahr 2001.

  13. Bewegungseinschränkung nach vorderer Kreuzbandrekonstruktion

    OpenAIRE

    Weig, Thomas G.

    2002-01-01

    5. Zusammenfassung: 223 Patienten , die sich einer Revision bei Bewegungseinschränkung nach Vorderer Kreuzbandrekonstruktion unterzogen hatten , wurden nachuntersucht. Es wurde eine Arthrofibrosegruppe (n=156; 70%) und eine Cyclops-Gruppe (n=67; 30%) gebildet. Es bestand ein durchschnittlicher Zeitraum zwischen Arthrolyse und Nachuntersuchung von 4,29 Jahren. Der Zeitabstand zwischen Unfall und vorderer Kreuzbandplastik, die Begleitverletzungen, der Reizzustand, die Schme...

  14. 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...

  15. IT-Compliance nach COBIT: Gegenüberstellung zwischen COBIT 4.0 und COBIT 5

    OpenAIRE

    Klotz, Michael

    2014-01-01

    Mit der aktuellen fünften Version (COBIT 5) wurden grundlegende Erweiterungen und Änderungen des COBIT-Frameworks vorgenommen. Inwieweit sich dies auf das IT-Compliance-Verständnis und das Management von IT-Compliance ausgewirkt hat, wird in diesem Arbeitspapier untersucht. Hierzu werden die vierte und die fünfte Version von COBIT auf ihre compliance-relevanten Aussagen hin untersucht und vergleichend gegenübergestellt. Im Ergebnis weist COBIT 4.0 in seiner Struktur zahlreiche Inkonsistenzen ...

  16. Determination and calculation of hazardous incident scenarios in accordance with the 3rd hazardous incident administrative instruction. Vol. 2; Ermittlung und Berechnung von Stoerfallablaufszenarien nach Massgabe der 3. Stoerfallverwaltungsvorschrift. Bd. 2: Berechnungsmethoden, aktuelle Modelle und Modellgleichungen

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, W; Rogazewski, P; Schindler, M [TUeV Anlagentechnik GmbH, Berlin-Schoeneberg (Germany). Unternehmensgruppe TUeV Rheinland/Berlin-Brandenburg; Acikalin, A; Albrecht, M; Lambert, M; Steinbach, J [Technische Univ. Berlin (Germany)

    2000-07-01

    Stoerfaellen sowie zu Bedingungen des Standortes und der Anlage die erforderlichen Grundannahmen zum Stoerfallablauf gewinnen kann. Unterschieden nach Stofffreisetzungen, Explosionen und Braenden wird jeweils auf die konkreteren Hinweise im Anhang 1 zur Abschaetzung von Quelltermen, im Anhang 2 zur Abschaetzung der Ausbreitung und im Anhang 3 zur Abschaetzung der Auswirkungen verwiesen. Der Anhang 4 enthaelt einige Erlaeuterungen zu den Anhaengen 1 bis 3. Mit einer Sammlung von 15 Beispielen fuer Stoerfallablaufszenarien wird im Anhang 5 das im Leitfaden beschriebene methodische Vorgehen veranschaulicht und erlaeutert. Im Anhang 6 werden die auf dem deutschen Markt erhaeltlichen DV-Programme (Software) zur Berechnung von Stoerfallablaufszenarien beschrieben und kommentiert. Der Band 2 untermauert das Vorgehen im Hinblick auf Berechnungsmethoden, aktuelle Modelle und Modellgleichungen aus wissenschaftlicher Sicht. (orig.)

  17. Diagnosis and therapy of dysfunctions of human leukocytes after irradiation. Final report; Diagnose und Therapie von Funktionsstoerungen menschlicher Leukozyten nach Bestrahlung. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Beuningen, D. van; Kaffenberger, W. [Sanitaetsakademie der Bundeswehr, Muenchen (Germany); Baaske, C.; Leipert, D.

    1999-08-01

    Immunkomplexe bzw. Phorbolester) aktiviert die NADPH-Oxidase auf parallel verlaufenden Signaltransduktionskaskaden, die in einer Aktivierung von Proteinkinase C-Isoenzymen zusammenlaufen. Einzelne Enzyme der Kaskaden wurden mittels pharmakologischer Inhibitoren in Verbindung mit dem 'Western'-Verfahren identifiziert, Lipid-'2{sup nd}-messenger' durch HPLC-Analyse. Die Daten weisen auf ein aeusserst komplexes System mit Quervernetzungen, Rueckkopplungen und Parallelschaltungen bei der Aktivierung der NADPH-Oxidase hin. Sie identifizieren erstmals mehrere zytoplasmatische/membranstaendige Elemente von Signaltransduktionskaskaden als strahlenempfindlich, die eine moegliche Basis fuer kausal-orientierte Therapieansaetze und eine Erklaerung fuer Immundefekte nach Bestrahlung bieten. (orig.)

  18. Zusammenführen was zusammengehört – Intellektuelle und automatische Erfassung von Werken nach RDA

    Directory of Open Access Journals (Sweden)

    Barbara Pfeifer

    2016-12-01

    Full Text Available Der Beitrag will die Erschließungspraxis der Deutschen Nationalbibliothek im ersten Implementierungsschritt der RDA zur Angabe der Werkebene darstellen, Erfahrungen zur grundsätzlichen Vorgehensweise und zu Sonderregelungen vermitteln und einen Ausblick in die Zukunft bieten. Die Angabe der Werkebene als Kernelement des neuen Standards wird bei der Erschließung von Ressourcen in der Deutschen Nationalbibliothek immer berücksichtigt. Bei der intellektuellen Erschließung von Monografien wird das Element als Normdatensatz oder als textuelle Angabe im Katalogisat erfasst. Allerdings setzt die derzeitige Praxis auch auf zukünftige automatische Clusterverfahren. Der erreichte Stand zu Algorithmen und Testläufen für das Werkclustering soll ebenso aufgezeigt werden, wie die daraus resultierenden Entscheidungen und die weitere Perspektive. Von zentraler Bedeutung ist die Frage, ob und unter welchen Bedingungen auf der Basis der Werkcluster Normdatensätze für die Gemeinsame Normdatei (GND generiert werden können, um sie im deutschen Sprachraum kooperativ zu nutzen und sie in der Linked-Data-Cloud zu vernetzen.   This article explains how works are catalogued at the Deutsche Nationalbibliothek (German National Library in the first implementation step of RDA. It discusses experiences with the general approach as well as some special rules and points out future prospects. When cataloguing resources at the Deutsche Nationalbibliothek, the work entity is always included as the work elements are core elements of the new standard. If the cataloguing is done intellectually, the work entity is described either as a link to an authority record or as a textual string within the description of the resource. However, the current practice builds also on automatic clustering of works in the future. The state of the art of automatic cluster algorithms and their evaluation and testing is described as well as the next steps for the future. An essential question

  19. Von Kalifornien nach Taxham / Katri Soe

    Index Scriptorium Estoniae

    Soe, Katri, 1971-

    2005-01-01

    Neljas osa magistritööst "Von Kalifornien nach Taxham: Formen und Strukturen der Kommunikation in Peter Handkes Romanen "Der kurze Brief zum langen Abschied" und "In einer dunklen Nacht ging ich aus meinem stillen Haus"" (Tartu, 2000. Juhendaja: Claus Sommerhage)

  20. Umgang mit Antithrombotika bei Operationen an der Haut vor und nach Publikation der entsprechenden S3-Leitlinie.

    Science.gov (United States)

    Gaskins, Matthew; Dittmann, Martin; Eisert, Lisa; Werner, Ricardo Niklas; Dressler, Corinna; Löser, Christoph; Nast, Alexander

    2018-03-01

    Laut einer Befragung im Jahre 2012 war der Umgang mit Antithrombotika bei dermatochirurgischen Eingriffen in Deutschland sehr heterogen. 2014 wurde erstmals eine evidenzbasierte Leitlinie zu diesem Thema veröffentlicht. Es wurde eine anonyme Befragung derselben Stichprobe zum Umgang mit Antithrombotika sowie zu Kenntnissen der Leitlinie durchgeführt. Die Ergebnisse wurden als relative Häufigkeiten berichtet und denen aus 2012 gegenübergestellt. 208 Antwortbögen wurden ausgewertet (Rücklaufquote: 36,6 %). Die große Mehrheit der Dermatologen erklärte, kleinere Eingriffe unter Fortführung der Therapie mit Phenprocoumon, niedrig dosierter Acetylsalicylsäure (≤ 100 mg) und Clopidogrel sowie mit direkten oralen Antikoagulanzien durchzuführen. Bei größeren Eingriffen war der Umgang hingegen weiterhin heterogen, insbesondere unter niedergelassenen Dermatologen. Der Anteil der Dermatologen, die Phenprocoumon, Acetylsalicylsäure und Clopidogrel leitlinienkonform verwendeten, hat sich insgesamt vergrößert. Führten 2012 beispielsweise 53,8 % der Klinikärzte bzw. 36,3 % der niedergelassenen Dermatologen eine große Exzision unter Fortführung der Therapie mit niedrig dosierter Acetylsalicylsäure durch, taten dies 2017 90,2 % bzw. 57,8 % (Phenprocoumon: 33,8 % bzw. 11,9 % auf 63,9 % bzw. 29,9 %; Clopidogrel: 36,9 % bzw. 23,2 % auf 63,9 % bzw. 30,6 %). Unter den Klinikärzten war ein hoher Anteil mit der Leitlinie vertraut und fand diese hilfreich. Eine Zunahme des leitlinienkonformen Verhaltens war bei allen Eingriffen zu verzeichnen. Bei größeren Eingriffen zeigte sich trotz deutlicher Verbesserung die Notwendigkeit verstärkter Anstrengungen zur Leitlinienumsetzung bzw. zur Identifizierung von Implementierungsbarrieren. © 2018 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  1. Intraindividual comparison of gastric peristalsis after ingestion of a semiliquid and solid test meal; Intraindividueller Vergleich der Magenperistaltik nach Gabe von semiliquiden und festen Testmahlzeiten

    Energy Technology Data Exchange (ETDEWEB)

    Linke, R. [Muenchen Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Tatsch, K. [Muenchen Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Muenzing, W. [Muenchen Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Vorderholzer, W. [Muenchen Univ. (Germany). Medizinische Klinik Innenstadt; Schindlbeck, N. [Muenchen Univ. (Germany). Medizinische Klinik Innenstadt; Hahn, K. [Muenchen Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    1997-06-01

    Aim: Patients with various disorders of gastric function were studied with radiolabeled test meals of different consistency to elaborate the effect of ingested media on gastric peristalsis and emptying. Methods: In 12 patients parameters of gastric function were intraindividually compared after ingestion of a semiliquid and a solid test meal. In addition to the standard evaluation derived from time activity curves condensed images were established from two fixed time intervals (early and late period). These images were used to evaluate the amplitude and frequency of gastric contractions using Fourier analysis. Results: As expected gastric emptying was influenced by the consistency of the test meal. Mean emptying rates for the solid meal were significant lower than those for the semiliquid one (p<0,01). The amplitude and frequency of gastric contractions, however, did not depend on the consistency of the test meal. Within the course of the examination contraction amplitudes significantly increased (p<0,05) from the early to the late period using both, solid as well as semiliquid test meals. The frequency of gastric contractions remained unchanged. Conclusion: As shown by an intraindividual data comparison amplitude and frequency of gastric contractions seem to be independent of the consistency of ingested test meals whereas gastric emptying is significantly influenced by the administered media. Semiliquid meals offer advantages with respect to the shorter examination time and simpler preparation and therefore may be preferred for routine use. Since amplitudes seem to vary within the observation period standardized acquisition protocols are recommended for the evaluation of this parameter. (orig.) [Deutsch] Ziel: An einem heterogenen Kollektiv von Patienten mit gastrointestinalen Beschwerden wurde der Einfluss von Testspeisen unterschiedlicher Konsistenz auf Peristaltik und Entleerungsrate des Magens untersucht. Methodik: Bei 12 Patienten wurde nach Gabe von

  2. Die Frage nach Gerechtigkeit.

    Directory of Open Access Journals (Sweden)

    Martin Jäggle

    2014-07-01

    Full Text Available ENGLISH: In the first part six stages in the author’s path of life are described, which have influenced his engagement with justice. The second part gives an insight into his religious educational work, in which the issue of justice was especially significant on the example of ‘religion in the context of migration’ and of the ecumenic initiative ‘lebens.werte.schule’ (school worth living. The vision of the Kingdom of God and the necessity of participation become apparent. DEUTSCH: Im ersten Teil werden sechs Stationen am Lebensweg des Autors beschrieben, die seine Auseinandersetzung mit Gerechtigkeit geprägt haben. Der zweite Teil gibt Einblick in seine religionspädagogische Arbeit, in der die Frage nach Gerechtigkeit besonders bedeutsam war am Beispiel ‚Religion im Kontext Migration‘ und der ökumenischen Initiative ‚lebens.werte.schule‘. Die Vision vom Reich Gottes und die Notwendigkeit von Partizipation werden dabei deutlich.

  3. Kardiovaskuläres Risikofaktorenprofil und Herzinfarktrisiko nach dem PROCAM-Index bei Männern mittleren Alters unter besonderer Berücksichtigung der EKG-Veränderungen unter Belastungsbedingungen

    OpenAIRE

    Kirchhof, M.R. (Monika)

    2006-01-01

    An 1248 Soldaten, wurde das kardiovaskuläre Risikofaktorenprofil bestimmt und das Herzinfarktrisiko nach dem PROCAM-Index ermittelt. Häufigkeit der Risikofaktoren: BMI?25kg/m2: 68,8%, positive Familienanamnese für Herzinfarkt 13,4%, Zigarettenrauchen 17,9%, körperliche Inaktivität 4,9%, systolischer RR?140mmHg: 50,9%, diastolischer RR?90mmHg: 41,4%, Gesamtcholesterin?5,2 mmol/l: 59,7%, HDL-Cholesterin?1,2 mmol/l: 33,5%, Gesamtcholesterin/HDL-Cholesterin-Quotient?4: 52,3%, LDL-Cholesterin ?4,...

  4. The risk for cancer and genetic abnormalities after radioiodine treatment of hyperthyroidism; Zum Krebs- und genetischen Risiko nach Radioiodtherapie der Hyperthyreose

    Energy Technology Data Exchange (ETDEWEB)

    Reiners, C. [Wuerzburg Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    1997-12-01

    According to recent studies, the risk for thyroid cancer is not increased after radioiodine treatment in patients with hyperthyroidism. Only the risk of cancer of the stomach seems to be increased slightly in patents treated with I-131 because of functional autonomy. However, the risk for gastric cancer is not increased after higher activities of I-131 because of thyroid cancer. There is no increased risk for genetic abnormalities after radioiodine treatment of hyperthyroidism. (orig.) [Deutsch] Aktuelle Studien zum Karzinomrisiko nach Radioiodtherapie wegen Hyperthyreose ergeben keinen Anhalt fuer eine erhoehte Inzidenz des Schilddruesenkarzinoms nach therapeutischer Gabe von I-131. Allenfalls scheint die Inzidenz von Magenkarzinomen bei Patienten nach Radioiodtherapie wegen funktioneller Autonomie geringfuegig erhoeht zu sein, obwohl diese Beobachtung bei Patienten nach hochdosierter Radioiodtherapie wegen eines Schilddruesenkarzinoms nicht gemacht wurde. Hinweise fuer ein erhoehtes genetisches Risiko nach Radioiodtherapie der Hyperthyreose ergeben sich nicht. (orig.)

  5. Determination and calculation of hazardous incident scenarios in accordance with the 3rd hazardous incident administrative instruction. Vol. 1; Ermittlung und Berechnung von Stoerfallablaufszenarien nach Massgabe der 3. Stoerfallverwaltungsvorschrift. Bd. 1: Methodischer Teil zum Erarbeiten von Stoerfallablaufszenarien

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, W.; Rogazewski, P.; Schindler, M. [TUeV Anlagentechnik GmbH, Berlin-Schoeneberg (Germany). Unternehmensgruppe TUeV Rheinland/Berlin-Brandenburg; Acikalin, A.; Albrecht, M.; Lambert, M.; Steinbach, J. [Technische Univ. Berlin (Germany)

    2000-07-01

    Stoerfaellen sowie zu Bedingungen des Standortes und der Anlage die erforderlichen Grundannahmen zum Stoerfallablauf gewinnen kann. Unterschieden nach Stofffreisetzungen, Explosionen und Braenden wird jeweils auf die konkreteren Hinweise im Anhang 1 zur Abschaetzung von Quelltermen, im Anhang 2 zur Abschaetzung der Ausbreitung und im Anhang 3 zur Abschaetzung der Auswirkungen verwiesen. Der Anhang 4 enthaelt einige Erlaeuterungen zu den Anhaengen 1 bis 3. Mit einer Sammlung von 15 Beispielen fuer Stoerfallablaufszenarien wird im Anhang 5 das im Leitfaden beschriebene methodische Vorgehen veranschaulicht und erlaeutert. Im Anhang 6 werden die auf dem deutschen Markt erhaeltlichen DV-Programme (Software) zur Berechnung von Stoerfallablaufszenarien beschrieben und kommentiert. Der Band 2 untermauert das Vorgehen im Hinblick auf Berechnungsmethoden, aktuelle Modelle und Modellgleichungen aus wissenschaftlicher Sicht. (orig.)

  6. Zukunftssicherung für die Zeit nach der Krise

    OpenAIRE

    Ackermann, Karl-Friedrich; Wehner, Martina

    2009-01-01

    Die Studie berichtet zusammenfassend über die Ergebnisse der 9. HR-Expertenbefragung mit der Zeitschrift „Personalwirtschaft“ zum Thema „Employer Branding“. Berichtet wird über die Verbreitung des Employer Branding, die dabei verfolgten Ziele und die Instrumente, mit denen ein erfolgreiches Employer Branding realisiert werden kann. Eng damit verbunden sind ergänzende Fragen nach den Einflussfaktoren und den Gestaltungsmöglichkeiten der Arbeitgebermarke sowie nach den eingesetzten Methoden zur...

  7. Dynamic MR imaging: Follow-up study after femoral head core decompression and rhBMP-2 instillation in patients with avascular necrosis of the femoral head; Dynamische Magnetresonanztomographie (MRT): Verlaufsbeobachtung nach Femurkerndekompression und Auffuellung mit rekombinantem, humanem Bone morphogenetic Protein-2 (rhBMP-2) bei avaskulaerer Femurkopfnekrose

    Energy Technology Data Exchange (ETDEWEB)

    Schedel, H. [Klinik Prof. Schedel, Kellberg (Germany); Schneller, A. [Humboldt-Universitaet, Berlin (Germany). Klinik fuer Allgemein- und Transplantationschirurgie; Vogl, T.; Mueller, H.F.; Maeurer, J.; Felix, R. [Humboldt-Universitaet, Berlin (Germany). Strahlenklinik und Poliklinik; Suedkamp, N. [Humboldt-Universitaet, Berlin (Germany). Unfall- und Wiederherstellungschirurgie; Eisenschenk, A. [Freie Univ. Berlin (Germany). Orthopaedische Klinik und Poliklinik

    2000-07-01

    Material and Methods: Six patients with avascular necrosis of the femoral head ARCO-stage I- or II-lesions were treated surgically by femoral head core decompression. Three of these patients were additionally treated with rhBMP-2-instillation. The progression or regression could be confirmed by T1- and T2-weighted spinecho-sequences (zero, four, ten, sixteen weeks and 24 months follow up). Results: Corresponding ARCO-classification with partly more sensitive measurement of vitality signs in comparison to the optical X-ray classification. The objective, quantitative measurement of signalintensity post contrast medium reduces the influence of experience and level of education. The dynamic sequences results are reproducable. (orig.) [German] Material und Methoden: Sechs Patienten mit avaskulaerer Nekrose des Femurkopfes des Stadiums I oder II nach ARCO wurden einer Femurkerndekompression unterzogen. Drei dieser Patienten erhielten zusaetzlich eine rhBMP-2-Auffuellung. Zum Zeitpunkt null, vier, zehn, sechszehn Wochen und 24 Monaten post OP erfolgte die kernspintomographische Untersuchung mit T1- und T2-gewichteten Sequenzen unter besonderer Beruecksichtigung der dynamischen Untersuchungssequenz nach Gabe von Gd-DTPA (Gadopentetsaeure, Dimegluminsalz; Magnevist {sup trademark}) zur Dokumentation der Signalintensitaetssteigerung pro Zeiteinheit in der Nekroseregion. Ergebnisse: Uebereinstimmende Stadienklassifikation nach ARCO mit zum Teil empfindlicherer Messung von Vitalitaetszeichen im Vergleich zu rein visuellen roentgenologischen Einteilung. Die objektive, quantitative Messung des Signalintensitaetssteigerungsverhaltens nach Kontrastmittelgabe im Bereich der Femurkopfnekrose kann den Einfluss von subjektiven Eigenschaften des Untersuchers (Erfahrung, Ausbildungsstand) reduzieren, wobei die Ergebnisse der Dynamiksequenzen objektiv reproduzierbar sind. (orig.)

  8. A Novel Large-scale Mentoring Program for Medical Students based on a Quantitative and Qualitative Needs Analysis [Aufbau eines innovativen Mentorenprogramms für eine große Zahl Medizinstudierender nach quantitativer und qualitativer Bedarfsanalyse

    Directory of Open Access Journals (Sweden)

    von der Borch, Philip

    2011-05-01

    Ludwig-Maximilians-Universität München (LMU und beschreiben die Einführung eines innovativen, umfassenden Mentorenprogramms.Methoden: Die Bedarfsanalyse wurde durch eine an alle Medizinstudierenden der Medizinischen Fakultät gerichtete Online-Umfrage durchgeführt (n=578 von 4.109 Studenten, Rücklauf 14,1%. Außerdem führten wir Fokusgruppen mit Medizinstudenten (n=24 und ärztlichem Personal (n=22 durch. Schließlich wurden alle Studierenden, die sich für das individuelle Mentorenprogramm interessierten, zu ihren Erwartungen befragt (n=534.Ergebnisse: 83% der Medizinstudierenden äußerten Zufriedenheit mit dem aktuellen Münchener Curriculum. Im Gegensatz dazu fühlten sich nur 36.5% der Studierenden unserer großen Fakultät ausreichend im Studium betreut, und 86% der Studierenden äußerten den Wunsch nach mehr Betreuung. Die Rolle ihres Mentors wünschten sich 55.6% "sehr" als Berater, Kontaktvermittler (36.4% und Ideenlieferant (28.1%. Die Themen, die angehende Mentees im Vorfeld "sehr" mit ihren Mentoren besprechen wollten, waren die Doktorarbeit (56.6%, das Praktische Jahr (55.8% und Auslandsaufenthalte (45.5%.Schlussfolgerungen: Wir haben anhand der Erkenntnisse unserer Bedarfsanalyse ein innovatives, zweigleisiges Konzept entworfen, das aus einem beliebig skalierbaren individuellen Mentorenprogramm für Studierende in klinischen Semestern und einem Peer Mentoring-Programm für sämtliche Medizinstudierende unserer Fakultät besteht. Ein Jahr nach der Initiierung des Programms haben über 300 Studierende im klinischen Studienabschnitt einen individuellen Mentor aus der Fakultät ausgewählt und 1.503 Studierende und Ärzte nahmen am Peer Mentoring teil.

  9. AOX determination in industrial waste water according to EN 1485, DEV H14. Experience with high salt freights and interfering organic matter; AOX-Bestimmungen in Industrieabwaessern nach EN 1485, DEV H14 Erfahrungen mit hohen Salzfrachten und organischen Stoerstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Helmreich, B. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl und Pruefamt fuer Wasserguete- und Abfallwirtschaft

    1999-07-01

    AOX determination in industrial waste water is not always trivial on account of high salt freights or high organic loads. Interfering substances of inorganic or organic nature can cause increases or decreases of readings that often are not plausible or reproducible. In most cases the AOX enrichment step is limiting to quantitative analysis. In the present work, enrichment in two industrial waste waters was critically assessed according to EN 1485 DEV H14. In addition, experience with the enrichment method according to Dr. Lange is reported. For the elimination of high salt freights beside a low organic concentration, cleanup by means of solid-phase extraction is considered. The results suggest that the standardized procedure is not universally applicable to any type of sample. However, appropriate action can minimize flaws of enrichment and, thereby, AOX determination. (orig.) [German] Die AOX-Bestimmung aus Industrieabwaessern ist aufgrund hoher Salzfrachten oder hoher organischer Belastungen nicht immer trivial. Stoerstoffe anorganischer wie auch organischer Art koennen zu Mehr- oder Minderbefunden fuehren, die oft nicht plausibel und reproduzierbar sind. In den meisten Faellen ist der Anreicherungsschritt des AOX fuer die quantitative Analyse limitierend. In der vorliegenden Arbeit wurde die Anreicherung nach den EN 1485 DEV H14 fuer zwei Industrieabwaesser kritisch betrachtet. Zudem werden Erfahrungen mit der Anreicherungsmethode nach Dr. Lange vorgestellt. Zur Entfernung hoher Salzfrachten neben einer geringen organischen Konzentration wurde ein Clean-up mittels Festphasenextraktion betrachtet. Die Ergebnisse legen nahe, dass das genormte Verfahren nicht universell auf jeden Probentyp anwendbar ist. Durch ein gezieltes Vorgehen koennen jedoch Fehler bei der Anreicherung und damit bei der AOX-Bestimmung minimiert werden. (orig.)

  10. Long term results of surgery in Perthes disease: Comparison of X-ray and MR-studies; Spaetergebnisse nach operativer Behandlung des Morbus Perthes: Vergleich der roentgenologischen und kernspintomographischen Untersuchung

    Energy Technology Data Exchange (ETDEWEB)

    Tosch, U. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Berlin (Germany); Sparmann, M. [Orthopaedische Klinik im Oskar-Helene-Heim, Berlin (Germany); Stelling, E. [Orthopaedische Klinik im Oskar-Helene-Heim, Berlin (Germany); Tomala, D. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Berlin (Germany)

    1995-05-01

    Twenty patients treated by surgery for Perthes` disease were studied between 4 and 9 years postoperatively. In the clinical investigation eight patients complained of persistent stress-induced pain. In nine patients flexion, extension, ab- and adduction of the hip joint was limited. In the MRI-Study of ten hip joints a reduction of fatty marrow was seen in the femoral head. In 11 hip joints of patients complaining of persistent pain, a deformation of the femoral head (n = 2), a dysplasia of the femoral metaphysis (n = 2), and diaphysis (n = 4) or both (n = 2) were seen. In another five patients an additional dysplasia of the acetabulum was visualized. All these findings were diagnosed by X-ray studies as well. However, only by MRI were the extents of the postoperative defects of femoral spongiosa diagnosed in fifteen hip joints. (orig.) [Deutsch] 20 wegen eines Morbus Perthes operierte Patienten wurden 4-9 Jahre nach einer Umstellungsosteotomie klinisch, radiologisch und kernspintomographisch untersucht. Bei der klinischen Nachuntersuchung gaben 8 Patienten persistierende Beschwerden bei Belastung an. Bei der koerperlichen Untersuchung war die Flexion und Extension bei 9 sowie die Abduktion und Adduktion bei einem Patienten eingeschraenkt. Bei der kernspintomographischen Untersuchung liessen sich bei 10 Hueftgelenken Residuen des M. Perthes im Fettmark des Femurkopfs nachweisen. An 11 Hueftkoepfen wurden pathologische Veraenderungen wie eine Femurkopfentrundung (n = 2), eine Deformierung der Femurmeta- (n = 3) und -diaphyse (n = 4) bis hin zur hirtenstabfoermigen Konfiguration (n = 2) nachgewiesen. Bei 5 Patienten wurde eine Pfannendysplasie gefunden. Diese Befunde waren auch roentgenologisch darzustellen. Als postoperative Defekte waren im Schaftmark des Femurs eine langstreckige Hoehlenbildung mit Zysten oder durch Fettmark aufgefuellte Spongiosadefekte bei 15 Hueftgelenken nur kernspintomographisch nachweisbar. (orig.)

  11. KlimaCH4. Climate effects of biomethane economy; KlimaCH4. Klimaeffekte von Biomethan

    Energy Technology Data Exchange (ETDEWEB)

    Westerkamp, Tanja; Reinelt, Torsten; Oehmichen, Katja; Ponitka, Jens; Naumann, Karin

    2014-07-01

    the identical period. In addition, with the optical remote measurement method one can from the time profile of the path-averaged concentrations in comparison with plant operation infer possible causes of increased emissions. This is mainly the case with operating problems with correspondingly high emissions. [German] Im Rahmen des Projektes ''Klimaeffekte einer Biomethanwirtschaft'' (KlimaCH4) wurden durch das Deutsche Biomasseforschungszentrum zwei Methoden fuer Messungen von direkten Treibhausgasemissionen hinsichtlich ihrer Anwendbarkeit und Vergleichbarkeit untersucht. Im Rahmen konkreter Messungen wurden die direkten Emissionen, v. a. von Methan, an drei Biogasanlagen mit Methanaufbereitung zur Einspeisung ins Erdgasnetz quantifiziert. Diese Untersuchungen erfolgten einerseits direkt vor Ort mittels Leckagesuche, Einhausungen und ''Open Chamber''-Messungen, andererseits indirekt mittels optischer Fernmessungen mit Tunable Diode Laser Absorption Spectrometry (TDLAS) und Quelltermrueckrechnung mittels inverser Ausbreitungsmodellierung. Die Vor-Ort-Methode bietet dabei die Moeglichkeit, die Einfluesse des Anlagenbetriebs auf die Emissionen bekannter diffuser Quellen zu untersuchen, u. a. durch den Abgleich des Betriebszustandes mit dem zeitlichem Verlauf der Emission einer bestimmten Quelle (z.B. erhoehte Methanfreisetzung aufgrund von Ruehrintervallen). Dies ist insbesondere fuer die Ableitung geeigneter Emissionsminderungsmassnahmen von zentraler Bedeutung. Die Quantifizierung einzelner, diffuser Emissionsquellen ist messtechnisch gegebenenfalls nur sehr aufwendig umsetzbar. Der Aufwand ist in erheblichem Masse von der Bauweise und Groesse der zu untersuchenden Biogasanlage abhaengig. Um den Einfluss jahreszeitlich wechselnder Umgebungsbedingungen zu erfassen wurden wiederkehrende Emissionsmessungen realisiert. Der Einsatz optischer Fernmesstechnik stellte sich als vorteilhafte Alternative zur Vor-Ort-Methode dar, da er

  12. KlimaCH4. Climate effects of biomethane economy; KlimaCH4. Klimaeffekte von Biomethan

    Energy Technology Data Exchange (ETDEWEB)

    Westerkamp, Tanja; Reinelt, Torsten; Oehmichen, Katja; Ponitka, Jens; Naumann, Karin

    2014-07-01

    the optical remote measurement method one can from the time profile of the path-averaged concentrations in comparison with plant operation infer possible causes of increased emissions. This is mainly the case with operating problems with correspondingly high emissions. [German] Im Rahmen des Projektes ''Klimaeffekte einer Biomethanwirtschaft'' (KlimaCH4) wurden durch das Deutsche Biomasseforschungszentrum zwei Methoden fuer Messungen von direkten Treibhausgasemissionen hinsichtlich ihrer Anwendbarkeit und Vergleichbarkeit untersucht. Im Rahmen konkreter Messungen wurden die direkten Emissionen, v. a. von Methan, an drei Biogasanlagen mit Methanaufbereitung zur Einspeisung ins Erdgasnetz quantifiziert. Diese Untersuchungen erfolgten einerseits direkt vor Ort mittels Leckagesuche, Einhausungen und ''Open Chamber''-Messungen, andererseits indirekt mittels optischer Fernmessungen mit Tunable Diode Laser Absorption Spectrometry (TDLAS) und Quelltermrueckrechnung mittels inverser Ausbreitungsmodellierung. Die Vor-Ort-Methode bietet dabei die Moeglichkeit, die Einfluesse des Anlagenbetriebs auf die Emissionen bekannter diffuser Quellen zu untersuchen, u. a. durch den Abgleich des Betriebszustandes mit dem zeitlichem Verlauf der Emission einer bestimmten Quelle (z.B. erhoehte Methanfreisetzung aufgrund von Ruehrintervallen). Dies ist insbesondere fuer die Ableitung geeigneter Emissionsminderungsmassnahmen von zentraler Bedeutung. Die Quantifizierung einzelner, diffuser Emissionsquellen ist messtechnisch gegebenenfalls nur sehr aufwendig umsetzbar. Der Aufwand ist in erheblichem Masse von der Bauweise und Groesse der zu untersuchenden Biogasanlage abhaengig. Um den Einfluss jahreszeitlich wechselnder Umgebungsbedingungen zu erfassen wurden wiederkehrende Emissionsmessungen realisiert. Der Einsatz optischer Fernmesstechnik stellte sich als vorteilhafte Alternative zur Vor-Ort-Methode dar, da er insbesondere an grossen Biogasanlagen bzw. Anlagen mit zahlreichen Einzelquellen den

  13. Urbanität nach exklusivem Rezept. Die Ausdeutung des Städtischen durch hochpreisige Immobilienprojekte in Berlin und Los Angeles

    Directory of Open Access Journals (Sweden)

    Henning Füller

    2013-07-01

    Full Text Available Innerstädtisches Wohnen steht zunehmend hoch im Kurs. Wahlweise als „Renaissance der Stadt“, Reurbanisierung oder Gentrifizierung thematisiert, ist das gegenwärtige Interesse von Investor_innen, Projektentwickler_innen und Käufer_innen an innerstädtischen Lagen prägnanter Ausdruck einer fortgesetzten Restrukturierung europäischer und US-amerikanischer Städte. Neben Prozessen der Inwertsetzung und Verdrängung umfasst diese Neuordnung auch die Ebene der Bedeutungen von Stadt und Urbanität. Insbesondere hochpreisige Neubauprojekte konkretisieren derzeit veränderte Vorstellungen bezüglich der Qualität der Stadt, ihrer Nutzer_innen und Nutzungsweisen. Der Beitrag zieht Projekte innerstädtischen Luxuswohnens in Berlin und Los Angeles heran, um dieser baulichen Konkretisierung von Diskursen um Stadt und Urbanität als Aspekt der gegenwärtigen „Renaissance der Stadt“ nachzugehen. In welcher Weise manifestieren sich Vorstellungen des erstrebenswerten städtischen Lebens in aktuellen Projekten hochpreisigen innerstädtischen Wohnungsbaus und welche Implikationen hat dies für die Gestalt der Stadt?

  14. Nachtraege zu den „Tertiaerschichten auf Java.” 1ter Nachtrag: Mollusken. Nach Sammlungen der Indischen Bergbeamten, Hunghuhn’s und Reinwardt’s

    NARCIS (Netherlands)

    Martin, K.

    1881-01-01

    Durch Vermittelung Verbeek’s erhielt ich eine grosse Reihe von Versteinerungen, welche von Bergbeamten Indiens (hauptsächlich von R. Everwijn und P. van Dijk) gesammelt waren und sich bis vor Kurzem, ohne näher untersucht zu sein, in Batavia befanden ¹). Diese Sammlung umfasste neben vielem

  15. Radiological risk assessment of isotope laboratories according to the requirements of the radiation protection ordinance and the protective labour legislation; Beurteilung des radiologischen Risikos von Isotopenlaboratorien nach den Vorgaben der Strahlenschutzverordnung und den Richtlinien fuer Arbeitssicherheit

    Energy Technology Data Exchange (ETDEWEB)

    Stuerm, R.P. [SafPro AG, Ausbildung und Beratung in Strahlenschutz, Basel (Switzerland); Kuster, M. [Novartis International AG, Corporate Health, Safety and Environment, Basel (Switzerland); Traub, K. [Novartis Pharma AG, Zentralstelle fuer Strahlenschutz, Basel (Switzerland)

    2001-07-01

    . 94). Isotopenlaboratorien der chemischen Industrie werden von der Schweizerischen Unfallversicherungsanstalt SUVA beaufsichtigt. Die SUVA nimmt nebst den Strahlenschutzaufgaben in den industriellen Betrieben auch die allgemeine Arbeitssicherheit wahr und hat Richtlinien zum Erstellen von Risikoanalysen erarbeitet. Bei diesen konventionellen Analysen werden die Arbeitsprozesse nach ihrem moeglichen Schadensausmass (Tod, schwere bleibende Gesundheitsschaden; leichter bleibender Gesundheitsschaden; heilbare Verletzung mit Arbeitsausfall; heilbare Verletzung ohne Arbeitsausfall) und der Eintretenswahrscheinlichkeit (haeufig; gelegentlich; selten; unwahrscheinlich; praktisch unmoeglich) in einer Risikomatrix beurteilt (grosse, mittlere und kleine Risiken). Die SUVA hat von zwei Baslern Isotopenlaboratorien des Typs B Risikobeurteilungen eingefordert, die einerseits die Gefaehrdung der Mitarbeiter und andererseits der Stadtbevoelkerung analysieren und radiologisch bewerten sollen. Fuer die Beurteilung des Mitarbeiterrisikos schlug sie vor, eine etablierte Methode aus der Arbeitssicherheit oder der Versicherungsbranche anzuwenden. Zudem muesse die Risikomatrix der von der Firmenleitung vorgegebenen Sicherheitskultur entsprechen. Damit standen wir vor dem Problem, radiologische Risiken, die sich als Strahlendosen in mSv ausdruecken lassen, fuer nicht radiologisch geschulte Manager mit den Folgen konventioneller Arbeitsunfaelle (Tod, Invaliditaet und Arbeitsausfall) bzw. mit den Reaktionen von Bevoelkerung und Politikern auf chemische Stoerfaelle zu vergleichen. Im Vortrag wird die aus Diskussionen mit der Aufsichtsbehoerde, der Firmenleitung, den Laborleitern und Labormitarbeitern entstandene Risikomatrix vorgestellt. Die Autoren sind der Meinung, dass bis anhin ein solcher Vergleich zwischen radiologischen und konventionellen Risiken noch nie etabliert worden sei und stellen ihr Resultat zur Diskussion. (orig.)

  16. Außergerichtliche Vollstreckung aus der Hypothek und Quasi-Datio in Solutum nach russischem Recht – Teil 2 / Tim Lassen

    Index Scriptorium Estoniae

    Lassen, Tim

    2014-01-01

    Hüpoteeklaenudega seotud vaidlustest Venemaal. Hüpoteekidega seotud õigusaktide rakendamise probleemidest ja vastavatest vahekohtu lahenditest. Järg. Algus Wirtschaft und Recht in Osteuropa 20014, nr. 5, lk. 136-140

  17. Present DDT and lindane indoor concentrations after extensive use of wood preservatives in attics in the past; Aktuelle DDT- und Lindan-Konzentrationen in Wohnraeumen nach intensivem Holzschutzmitteleinsatz auf Dachboeden in der Vergangenheit

    Energy Technology Data Exchange (ETDEWEB)

    Rosskamp, E.; Horn, W.; Ullrich, D.; Seifert, B. [Umweltbundesamt, Berlin (Germany). Inst. fuer Wasser-, Boden- und Lufthygiene

    1999-12-01

    ausgebauten Dachwohnungen zu bestimmen. Die untersuchten behandelten Dachboeden wiesen - z.T. auch ueber 20 Jahre nach Anwendung des Schutzmittels - DDT- und Lindan-Luftkonzentrationen bis zu 4600 ng/m{sup 3} bzw. 930 ng/m{sup 3} auf. In den ausgebauten Dachwohnungen und in den Wohnungen direkt unter den behandelten Dachboeden waren die Konzentrationen an DDT und Lindan jedoch wesentlich niedriger. Die Medianwerte lagen fuer DDT bei 20 bzw. 40 ng/m{sup 3} und fuer Lindan bei 5 bzw. 20 ng/m{sup 3}. Lediglich in einigen Wohnungen betrug die DDT- oder Lindan-Konzentration in der Luft mehr als 100 ng/m{sup 3}. In diesen Faellen war auch eine direkte Biozidanwendung in den Raeumen vorgenommen worden oder es bestand direkter Luftaustausch mit einem DDT-belasteten Dachraum. Eine Exposition der Wohnungsnutzer gegenueber DDT und Lindan kann sowohl ueber die Innenraumluft als auch - insbesondere fuer Kleinkinder mit ihrem spezifischen Spielverhalten - ueber den Hausstaub erfolgen. In Wohnraeumen wurden maximal 200 mg DDT/kg Staub nachgewiesen, der Median lag mit 20 mg/kg eine Groessenordnung niedriger. Die Lindan-Staubgehalte lagen alle unter 9 mg/kg. Die fuer Kleinkinder moegliche Exposition gegenueber DDT oder Lindan im Hausstaub liegt weiter unter den aus dem ADI-Wert der WHO abgeleiteten zulaessigen Aufnahmemengen. (orig.)

  18. Early clinical phase of patient's management after polytrauma using 1- and 4-slice helical CT; Fruehes klinisches Management nach Polytrauma mit 1- und 4-Schicht-Spiral-CT

    Energy Technology Data Exchange (ETDEWEB)

    Kloeppel, R.; Kahn, T. [Klinik und Poliklinik fuer Diagnostische Radiologie, Universitaetsklinikum Leipzig (Germany); Schreiter, D. [Chirurgische Intensivtherapieabteilung, Zentrum fuer Chirurgie, Universitaetsklinikum Leipzig (Germany); Dietrich, J. [Abt. Neuroradiologie der Klinik und Poliklinik fuer Diagnostische Radiologie, Universitaetsklinikum Leipzig (Germany); Josten, C. [Klinik und Poliklinik fuer Unfall- und Wiederherstellungschirurgie, Zentrum fuer Chirurgie, Universitaetsklinikum Leipzig (Germany)

    2002-07-01

    In the early clinical phase the comprehensive imaging of patients with multiple trauma using helical CT is already established. Aim of this study was to assess whether MSCT may improve the patient management and the diagnostic results.The procedure is designed as follows: after life-thretening treatment x-ray of chest and ultrasound are carried out in the emergency room. Then the patient is moved to CT. From 1998 to december 2000 241 patients were examined using a single slice helical CT (Somatom plus 4), in 2001 79 patients using a 4-slice helical CT (Somatom VZ, Siemens Med.Sol.). After CT selected radiograms of the extremities were taken.359 of 360 procedures were carried out successfully. Excluding 1 case (death during 1-sl. h CT) all relevant lesions of head, neck, and body were diagnosed. Although the patients had an injury severity score of {approx}30. The change from 1slice-helical CT to 4 slice-helical CT allowed us to reduce the stay in the CT room from 28 to 16 min. The total lethality decreased by {approx}4%.Advantages for the patient arose from the standardized examination protocol using multislice CT. If integrated in an interdisciplinary management concept, it is a good compromise between examination time, comprehensive diagnostic imaging, life-saving therapeutic procedures, and therapy planning. (orig.) [German] Die klinische Erstversorgung Polytraumatisierter schliesst inzwischen in vielen Unfallkliniken den fruehzeitigen Einsatz der Spiral-CT ein. Kann die neuerlich eingefuehrte Mehrschicht-Spiral-CT Ergebnisse und Patientenmanagement weiter verbessern?Nach lebensrettenden Sofortmassnahmen, Thoraxroentgen und Notsonographie im Schockraum erfolgte die CT: Von 1998-2000 wurden 241 Patienten mit einem 1-Schicht-Spiral-CT (Somatom plus 4) und in 2001 79 Patienten mit einem 4-Schicht-Spiral-CT (Somatom VZ, beide Siemens Med. Sol.) untersucht. Klinisch ausgewaehlte Extremitaetenaufnahmen wurden ergaenzt.359 von 360 Untersuchungen verliefen erfolgreich

  19. Analysis of binding delivery agreements in electricity supply contracts from the angle of German and EC antitrust law; Die Beurteilung von Bezugsbindungen in Elektrizitaetsliefervertraegen nach deutschem und EG-Kartellrecht

    Energy Technology Data Exchange (ETDEWEB)

    Scholz, U.

    1998-12-31

    Binding delivery agreements in the form of contractual clauses determining exclusive total or partial coverage of electricity demand, take-or-pay contracts, or minimum purchase quota, are standard provisions of energy supply contracts concluded in order to ensure amortization of earlier commitments such as investment or other obligations. In the wake of the recent amendment of the German energy industry law for implementation of the deregulation of electricity markets in EU Member States, those agreements have become items of concern in the eyes of the cartel authority. In Germany, where utilities as from 1990 had to invest particularly strongly into the modernisation of existing power plants and distribution systems in the eastern parts of the country, review of the legality of those agreements touches upon vital interests of the electric power industry. The article here examines the situation with reference to EU legislation and the German law against restraints on competition (GWB). (orig./CB) [Deutsch] Bezugsbindungen in Gestalt von Gesamt- oder Teilbedarfsdeckungsklauseln, Take-or-Pay-Verpflichtungen oder Mindestbezugspflichten sind regelmaessig Bestandteile von Elektrizitaetsliefervertraegen, die zum einen der Amortisation bereits getaetigter Investitionen sowie eingegangener Verpflichtungen dienen. Insbesondere nach der Reform des deutschen Energiewirtschaftsrechts gewinnt die Frage der kartellrechtlichen Zulaessigkeit von Bezugsbindungen besondere Relevanz. Nicht zuletzt vor dem Hintergrund der besonders kapitalintensiven Investitionen zur Modernisierung der ostdeutschen Elektrizitaetsversorgung stellt sich daher die Frage, ob und inwieweit Bezugsbindungen nach der Aenderung des rechtlichen Ordnungsrahmens in der leitungsgebundenen Energieversorgung zulaessig sind. Der rechtliche Rahmen fuer die Beurteilung der Zulaessigkeit von Bezugsbindungen wird insbesondere durch die EU-Wettbewerbsregeln sowie die Bestimmungen des GWB gebildet. (orig.)

  20. Substanzbegriff und systematik

    NARCIS (Netherlands)

    Lütjeharms, W.J.

    1934-01-01

    Bei der Einteilung der Organismen, welche in dieser Arbeit mir von botanischem Gesichtspunkt betrachtet wird, ist die Frage nach „wesentlichen” Merkmalen oder Einteilungsgründen von grosser Wichtigkeit. Es ist die Frage nach der Substanz (Essenz) und den akzidentellen Merkmalen. Der Substanzbegriff

  1. (CH4)-C-14 Measurements in Greenland Ice: Investigating Last Glacial Termination CH4 Sources

    DEFF Research Database (Denmark)

    Petrenko, V. V.; Smith, A. M.; Brook, E. J.

    2009-01-01

    by direct cosmogenic C-14 production in ice. C-14 of CO was measured to better understand this process and correct the sample (CH4)-C-14. Corrected results suggest that wetland sources were likely responsible for the majority of the Younger Dryas-Preboreal CH4 rise.......The cause of a large increase of atmospheric methane concentration during the Younger Dryas-Preboreal abrupt climatic transition (similar to 11,600 years ago) has been the subject of much debate. The carbon-14 (C-14) content of methane ((CH4)-C-14) should distinguish between wetland and clathrate...... contributions to this increase. We present measurements of (CH4)-C-14 in glacial ice, targeting this transition, performed by using ice samples obtained from an ablation site in west Greenland. Measured (CH4)-C-14 values were higher than predicted under any scenario. Sample (CH4)-C-14 appears to be elevated...

  2. Postoperative and posttherapeutic changes after primary bone tumors. What's important for radiologists?; Postoperative und posttherapeutische Veraenderungen nach primaeren Knochentumoren. Was ist wichtig fuer den Radiologen

    Energy Technology Data Exchange (ETDEWEB)

    Grieser, T. [Klinikum Augsburg, Klinik fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie, Augsburg (Germany); Noebauer-Huhmann, I.M. [Med. Universitaet Wien, Univ.-Klinik fuer Radiologie und Nuklearmedizin, Wien (Austria)

    2017-11-15

    Posttreatment imaging of primary bone tumours represents a diagnostic challenge for radiologists. Depending on the primary bone tumour common radiological procedures, such as radiography, computed tomography (CT), and magnetic resonance imaging (MRI), are employed. Radiography and CT are particularly useful in benign bone tumours and in matrix-forming bone tumours. MRI comes into consideration with malignant tumour recurrence and tumoral soft tissue infiltration. Bone scintigraphy is of superior importance if a primarily multifocal manifestation of bone tumour or metastasizing tumour disease is suspected. Molecular imaging (FDG-PET and hybrid imaging, using CT) are gaining increasing importance in light of monitoring neoadjuvant chemotherapy and detecting recurrent tumour appearance. The current literature shows sensitivity and specificity values for recurrent detection of up to 92% and 93%. Diagnostic accuracy is as high as 95%, thus, exceeding accuracy values for CT (67%) and MRI (86%) by far. Likewise, this is also applicable for the assessment of the neoadjuvant chemotherapy. Moreover, PET-based modalities are able to establish prognostic statements using SUV-threshold values at baseline (especially for Ewing sarcomas). Advanced imaging techniques have made a great diagnostic step forward and have proven to be relevant and reproducible with respect to both relapse detection and treatment assessment. Furthermore, it is not clear whether a higher detection rate of early tumour recurrence will inevitably lead to better outcome and survival. (orig.) [German] Die posttherapeutische Bildgebung primaerer Knochentumoren stellt eine diagnostische Herausforderung fuer jeden Radiologen dar. In Abhaengigkeit vom primaeren Knochentumor werden zur Nachsorge die gaengigen radiologischen Standardverfahren eingesetzt (Projektionsradiographie, Computertomographie [CT] und Magnetresonanztomographie [MRT]). Die Projektionsradiographie und CT haben einen besonderen Stellenwert v. a

  3. Pyrrole and 2,5-heptanedione in the urine of rats and 2,5-heptanedione in the urine of man: analytical determination of excretion upon exposure to n-heptane; Pyrrole und 2,5-Heptandion im Urin der Ratte und 2,5-Heptandion im Urin des Menschen: Analytische Bestimmung der Ausscheidung nach Exposition gegn n-Heptan

    Energy Technology Data Exchange (ETDEWEB)

    Stoermer, A.G.C.

    1997-09-01

    A method for quantifying levels of the neurotoxic metabolite 2,5-heptanedione in rats and man after experimental exposure to n-heptane was developed. It consisted in determining the quantity of 2,5-heptanedione excreted in urine and the relevant excretion kinetics. Moreover, the excretion of pyrrole in the urine of rats was measured. In the urine of non-exposed rats and man, a basic excretion of 2,5-heptanedione was measured, with the rates of excretion being 0.11 and 4.5 nmol per hour, respectively. This basic excretion of 2,5-heptanedione is assumed to have an endogenous cause. The quantitive investigation of the dose dependence of the excretion of 2,5-heptanedione and pyrrole in the urine of rats and of 2,5-heptanedione in the urine of man is a prerequisite for assessing the risk posed by n-heptane with a view to peripheral neuropathies. (orig./MG) [Deutsch] Ziel dieser Arbeit war die Entwicklung einer Methode zur Quantifizierung der Belastung von Ratte und Mensch mit dem neurotoxischen Metaboliten 2,5-Heptandion nach experimentellen Expositionen gegen n-Heptan. Dazu sollte jeweils die ausgeschiedene Menge und die zugehoerige Ausscheidungskinetik von 2,5-Heptandion im Urin bestimmt werden. Darueber hinaus sollte die Ausscheidung von Pyrrolen im Urin von Ratten gemessen werden. Im Urin von nicht exponierten Ratten und Menschen wurde eine Grundausscheidung von 2,5-Heptandion gefunden, wobei die Ausscheidungsraten jeweils 0,11 bzw. 4,5 nmol/h betrugen. Fuer die Grundausscheidung von 2,5-Heptandion wird ein endogener Ursprung angenommen. Die quantitativen Untersuchungen zur Dosisabhaengigkeit der Ausscheidung im Urin von 2,5-Heptandion und Pyrrolen bei der Ratte und von 2,5-Heptandion beim Menschen sind eine Grundvoraussetzung fuer eine Abschaetzung des Risikos von n-Heptan fuer periphere Neuropathien. (orig./MG)

  4. Signifikante Verbesserungen eines klinischen Untersuchungskurses nach einfachen strukturierten Veränderungen des Lehrinhalts und der Lehrmethoden [Significant improvement of a clinical training course in physical examination after basic structural changes in the teaching content and methods

    Directory of Open Access Journals (Sweden)

    Bott-Flügel, Lorenz

    2013-05-01

    von ihnen erlernten Untersuchungstechniken führen.Methoden: In drei medizinischen Kliniken der Technischen Universität München wurden im Sommersemester 2010 die quantitativen Evaluationsergebnisse (deutsches Schulnotensystem, Noten 1-6 von insgesamt 49 Studierenden von einem Kurstag vor und einem Kurstag nach strukturierten Verbesserungsmaßnahmen des klinischen Untersuchungskurses verglichen. Zum Einsatz kamen strukturierte Instruktion der Dozenten, Handouts und über das Internet verfügbares Zusatzmaterial.Ergebnisse: Es wurden 47 Evaluationsbögen vor und 34 Evaluationsbögen nach den Verbesserungsmaßnahmen ausgefüllt. Die oben genannten Maßnahmen führten zu signifikanten Verbesserungen der Evaluationsnoten in folgenden Bereichen: Einführen ins jeweilige Kursthema (von 2,4±1,2 auf 1,7±1,0, p=0,002 und in hygienische Maßnahmen (von 3,8±1,9 auf 2,5±1,8, p=0,004, strukturiertes Vorführen der einzelnen Untersuchungsschritte (von 2,9±1,5 auf 1,8±1, p=0,001, Üben der Untersuchungsschritte (von 3,1±1,8 auf 2,2±1,4, p=0,030, strukturiertes Feedback zur Untersuchungstechnik (von 3,0±1,4 auf 2,3±1,0, p0,=0,007, Verwenden von Handouts (von 5,2±1,4 auf 1,8±1,4, p<0,001, Tipps zu weiterem Lernmaterial (von 5,0±1,4 auf 3,4±2,0, p<0,001, Lernerfahrung insgesamt (von 2,4±0,9 auf 1,9±0,8, p=0,017 und Selbsteinschätzung der Studenten bezüglich der Sicherheit bei der Durchführung einer körperlichen Untersuchung (von 3,5±1,3 auf 2,5±1,1, p<0,001.Zusammenfassung: Strukturierte Verbesserungsmaßnahmen führten zu signifikanten Verbesserungen der Evaluationsnoten eines klinischen Untersuchungskurstages in den Bereichen „Vorbereitung der Dozenten“, „Struktur des Kurses“ und „selbst eingeschätzte Sicherheit beim Durchführen einer Untersuchung“.

  5. Einmaliges studentisches standardisiertes Training der chirurgischen Händedesinfektion nach EN1500: Quantifizierung des Trainingseffektes, Nutzen der Methode und Vergleich mit klinischen Referenzgruppen [A single standardized practical training for surgical scrubbing according to EN1500: Effect Quantification, value of the standardized method and comparison with clinical reference groups

    Directory of Open Access Journals (Sweden)

    Wullenk, Katharina

    2013-05-01

    Full Text Available [english] The standardized training of practical competences in skills labs is relatively new among German Medical Faculties. The broad acceptance and outstanding evaluation results do not provide objective data on the efficiency and cost-efficiency of these trainings. This study aims on the quantification of the teaching effect of the surgical scrubbing technique EN1500 and its comparison with clinical references of OR personnel.Methods: 161 4 year medical students were randomized into intervention and control group. The intervention group received a 45 minute standardized peer-teaching training of practical competences necessary in the OR including the scrubbing according to EN1500. Fluorescence dye was mixed in the disinfectant solution. After hand disinfection, standardized fotographs and semi-automated digital processing resulted in quantification of the insufficiently covered hand area. These results were compared with the control group that received the training after the test. In order to provide information on the achieved clinical competence level, the results were compared with the two clinical reference groups.Results: The intervention group remained with 4,99% (SD 2,34 insufficiently covered hand area after the training compared to the control group 7,33% (SD 3,91, p[german] Die standardisierte Schulung klinisch-praktischer Fertigkeiten in sog. Skills Labs ist erst seit wenigen Jahren an deutschen Universitäten verbreitet. Den zumeist umfangreichen und sehr guten Evaluationsergebnissen stehen kaum Untersuchungen zur Effektquantifizierung und Kosten-Nutzen-Analyse gegenüber. In der vorliegenden Studie soll eine Methode zur digitalen Quantifizierung der Güte der chirurgischen Händedesinfektion vorgestellt werden sowie das Skills-Lab-Training der standardisierten Einreibemethode nach EN1500 auf seinen Effekt hin untersucht und mit OP-Pflegepersonal und Operateuren als klinische Referenzgruppen verglichen werden.Methode: 161

  6. Tropospheric radiative forcing of CH4

    International Nuclear Information System (INIS)

    Grossman, A.S.; Grant, K.E.

    1994-04-01

    We have evaluated the tropospheric radiative forcing of CH 4 in the 0-3000 cm -1 wavenumber range and compared this with prior published calculations. The atmospheric test cases involved perturbed methane scenarios in both a McClatchey mid latitude, summer, clear sky approximation, model atmosphere, as well as a globally and seasonally averaged model atmosphere containing a representative cloud distribution. The scenarios involved pure CH 4 radiative forcing and CH 4 plus a mixture of H 2 O, CO 2 , O 3 , and N 2 O. The IR radiative forcing was calculated using a correlated k-distribution transmission model. The major purposes of this paper are to first, use the correlated k-distribution model to calculate the tropospheric radiative forcing for CH 4 , as the only radiatively active gas, and in a mixture with H 2 O, CO 2 , O 3 , and N 2 O, for a McClatchey mid-latitude summer, clear-sky model atmosphere, and to compare the results to those obtained in the studies mentioned above. Second, we will calculate the tropospheric methane forcing in a globally and annually averaged atmosphere with and without a representative cloud distribution in order to validate the conjecture given in IPCC (1990) that the inclusion of clouds in the forcing calculations results in forcing values which are approximately 20 percent less than those obtained using clear sky approximations

  7. Polilingvizmas kaip „grįžimas namõ“: tarp Babilono katastrofos ir Jeruzalės Sekminių stebuklo. Vlado Braziūno poezijos at(sivėrimai | Der Polylinguismus als „Rückkehr nach Hause“: zwischen der babylonischen Katastrophe und dem Pfingstwunder von Jerusalem

    Directory of Open Access Journals (Sweden)

    Skirmantas Valentas

    2006-01-01

    Full Text Available In diesem Beitrag wird ein Versuch unternommen, die Widerspiegelung von zwei philologisch wichtigen Episoden der Heiligen Schrift in der modernen Poesie zu vermitteln. Es geht um die Erzählung von der babylonischen Sprachenverwirrung im Buch der Anfänge und um das in den Apostelgeschichten erwähnte Pfingstwunder, die beide unter einen Begriff Polylinguismus fallen.Der Polylinguismus in der Poesie ist als eine syntagmatische Mehrsprachigkeit, anders gesagt, als eine implizite Benennung desgleichen Denotats in einigen Sprachen, zu betrachten.Der verallgemeinernde Begriff „Rückkehr nach Hause“ lässt zwei Begriffe in Verbindung setzen: die sich nach der babylonischen Katastrophe etablierte Mehrsprachigkeit und das Pfingstwunder als eine Möglichkeit die verwirrten Sprachen wieder zu einem Harmonischen zusammenzufügen.Da die Poesie als ein Grammatik modellierender Text vorliegt, ist eine Idee hervorzuheben, dass neben einer üblichen Sprache in der Poesie eine andere Sprache mit völlig anderen Regeln aufgedeckt werden muss.Als eines der Grundmerkmale der üblichen Sprache ist ein in ihr enthaltenes Oppositionsystem zu betrachten. Als Grundmerkmal einer anderen Sprache gilt dagegen das Schwinden der grundlegenden Oppositionen, das einen endlosen und periodischen Text schafft.Der Polylinguismus der Poesie wird in den linguistischen Geschichten am deutlichsten sichtbar. Der Polylinguismus in der Poesie, der dem Simultandolmetschen nahsteht, führt uns auf das Pfingstwunder zurück.

  8. Substancinė Dievo formos kaita kaip meninė Visybės reprezentacija (pagal Thomo Manno romaną Juozapas ir jo broliai | Substanziales Werden der Form Gottes als künstleriche Repräsentation des Ganzen (nach der Tetralogie Joseph und seine Brüder von Thomas Mann

    Directory of Open Access Journals (Sweden)

    Juldita Nagliuvienė

    2004-01-01

    Full Text Available Anhand der Polemik zwischen der Totalitätsphänomenologie von Emmanuel Lévinas und der Selbstphänomenologie von Ernst Bloch werden in diesem Artikel die Erscheinungen Gottes, mit denen sich das patriarchalische Subjekt in die Beziehung eingetreten ist, analysiert. Vor allem aktualisiert man den substanziellen Inhalt der künstlerichen Gottesform, deren Wurzeln in der primitiven archaischen Ikonographie der Babylonier und der Ägypter liegen. Das Bild Gottes verwandelt sich in der Situation der Begegnung aus der Substanz des unförmigen Steines, die pfallische Intentionen des Helden akzentuiert, in die symbiotische Form eines Menschentieres (oder Gottes-Tieres, das als Fremde Gott auf der Ebene der Erzählung funktioniert und den Numenaspekt durch die künstliche Form der animalischen Gottheit in sich trägt. Durch die Maske des Tieres strebt der göttliche Begegnungspartner, der das Werden Gottes aktualisiert, nach der Verwandlung in die Gestalt eines sterbenden und wieder auferstehenden Menschen-Gottes, der den sündigen Menschen erlösen kann. In der Tetralogie von Thomas Mann existiert diese Ebene des Nochnicht-gewordenen-Gottes als utopische Stufe der vollkommenen Beziehungen zwischen Mensch und Gott. Die Begegnung zwischen dem tierischen Gott und dem Helden geschieht im Roman in der Traumsphäre, die den Dialog zwischen dem Kunstding und dem Menschen möglich macht. Auf der Traumebene wird der Prozess der Metamorphose einer Gottheit dargestellt, aber sie erscheint als ein schon verwandeltes Wesen, das die Antropomorphie des Erlösungsprinzips aufnimmt, und dem Helden erst im bewussten Zustand begegnet.

  9. Fotografie und atomare Katastrophe

    OpenAIRE

    Bürkner, Daniel

    2015-01-01

    Die Dissertation setzt sich mit den fotografischen Repräsentationen der Atombombenabwürfe auf Hiroshima und Nagasaki sowie der Havarie des Kernkraftwerks Tschernobyl auseinander. Dabei werden künstlerische, dokumentarische und touristische Bilder analysiert, die sich der jeweiligen Strahlenkatastrophe oftmals erst Jahre nach dem Ereignis annehmen und ikonografische oder medial-materielle Bezüge zu ihr aufweisen. Es zeigen sich zentrale Strategien, atomare Katastrophen, seien sie militäri...

  10. Signale ohne Antwort? Die Suche nach außerirdischem Leben.

    Science.gov (United States)

    Davoust, E.

    This book is a German translation, by M. Röser, of the English version "The cosmic water hole", published in 1991 (see 53.003.080). The original French edition "Silence au point d'eau" was published in 1988 (see 45.003.059). Contents: I. Leben auf der Erde. 1. Kometen und der Ursprung des Lebens. 2. Die zeitliche Dimension des Lebens. 3. Evolution und Katastrophen. 4. Liegt unsere Zukunft im Weltall? II. Leben im Universum. 5. Die Suche nach Leben in der Sonnenumgebung. 6. Die Suche nach Planetensystemen. III. Intelligentes Leben im Universum. 7. Demographie außerirdischer Zivilisationen. 8. Soziologie außerirdischer Zivilisationen. 9. UFO's und Besuche in der Vergangenheit. 10. Strategien bei der Suche nach außerirdischen Zivilisationen. 11. Die Suche nach künstlichen Signalen. 12. Die Diskussion innerhalb der Gesellschaft. 13. Die Stellung des Menschen im Universum.

  11. Arbeitszeitflexibilisierung in der westdeutschen Metall- und Elektroindustrie und die Verbandsstrategien - Eine vergleichende Analyse der arbeitszeitpolitischen Strategien des Arbeitgeberverbandes Gesamtmetall und der Industriegewerkschaft Metall

    OpenAIRE

    Altun, Ufuk

    2005-01-01

    Arbeitszeitpolitik und Arbeitszeitgestaltung haben seit dem Tarifkompromiss im Jahre 1984 in der Metall-, und Elektroindustrie in der politischen und wissenschaftlichen Diskussion einen immensen Bedeutungszuwachs erfahren. Die Forderungen nach einer flexibleren Arbeitszeitgestaltung haben zeitgleich sowohl aus der Globalisierungsdiskussion und der Debatte um die Wettbewerbsfähigkeit des "Wirtschaftsstandorts Deutschland" heraus wie auch aus beschäftigungspolitischen Gründen neuen Auftrieb bek...

  12. Stabilität und Frieden? Ehebeziehungen im Transformationsprozeß

    Directory of Open Access Journals (Sweden)

    Martina Ritter

    2001-03-01

    Full Text Available In der sehr guten Studie, die auf der Kooperation von amerikanischen und russischen Forscherinnen beruht, werden die ehelichen Beziehungen im gegenwärtigen Rußland diskutiert. Nach einer kontextuellen Einbettung in eine historische Reflexion über die Entwicklung von Ehe und Familie in Rußland und der Sowjetunion und nach transformationstheoretischen Überlegungen werden Themen wie Geschlechterbilder, Arbeitsteilung, Ehe-Qualität und Gewalt mit Hilfe quantitativer Methoden analysiert.

  13. Suche nach Charginos in 4 Jet Ereignissen bei LEP2

    CERN Document Server

    AUTHOR|(CDS)2086503

    1997-01-01

    Zum heutigen Tag sind der Hochenergiephysik einige Hundert Teilchen und Teilchenzustände bekannt, die dem Anschein nach auf sehr komplexe Weise wechselwirken und so die beobachtbare Welt konstituieren. Bei näherer Betrachtung sind jedoch nur wenige Teilchen und Wechselwirkungen elementar, in dem Sinne, dass die übrigen sich als aus ihnen zusammengesetzt ansehen lassen. Die Frage, wie man diese elementaren Teilchen und ihre fundamentalen Wechselwirkungen systematisch beschreiben kann, beantwortet das Standardmodell der Elementarteilchenphysik. Es verwendet das Spektrum der fundamentalen Materie, die inneren Symmetrieeigenschaften dieses Spektrums und das Eichprinzip, um eine Beschreibung im Rahmen der Quantenfeldtheorie zu formalisieren. Das Standardmodell leistet so eine prinzipielle Beschreibung der bis heute betrachteten Hochenergiephysik. Dabei treten allerdings einige Probleme auf, die es attraktiv erscheinen lassen, das Standardmodell um eine weitere Symmetrieeigenschaft zu erweitern, nämlich um die ...

  14. Length change of the alloys Waspaloy and Inconel 718 after long-term annealing; Laengenaenderung der Legierungen Waspaloy und Inconel 718 nach Langzeitauslagerung

    Energy Technology Data Exchange (ETDEWEB)

    Kinzel, Svenja

    2016-07-01

    of contraction is reversible. It causes an increase in lattice parameter and the Ni-Cr domains formed at lower temperatures are dissolved by the influence of higher temperatures. The sample elongation caused by stress relief heat treatment therefore is more pronounced for samples annealed at lower temperatures. The combination of lattice parameter change and formation of Ni-Cr rich domains explains the sample behavior within the first 300 hours. The further, slowly proceeding contraction for longer annealing times refers to carbide transformation. Particles of TiC and Ti(N,C) slowly dissolve in a peritectic reaction. An extrapolation of the results shows that complete dissolution will be reached after 14,000,000 hours (= 1,600 years). Dissolution of these phases leads to sample contraction reaching values of about -4,0.10{sup -4} after 10,000 hours. A contrary effect is caused by the concurrent formation of Cr{sub 23}C{sub 6}, which consumes the free C-atoms from carbide dissolution. Formation of this carbide type with 1.4% volume fraction is finished after 16,000,000 h (= 1,800 years). Within 10,000 h the phase formation leads to sample elongation of about +3,4.10{sup -4}. The combination of both effects almost cancels out and therefore only causes contraction of about -0,6.10{sup -4}, which is about 30% of the measured contraction. When the carbide transformation is complete, no further length change is expected. Although conditions are more complicated for alloy Inconel 718 due to the presence of additional phases (γ'' und δ-phase) the results can transferred in principal. The measured sample contraction is lower than for Waspaloy. Within the investigated temperature range the calculated phase diagram shows significant changes only for the phase fraction of γ{sup '} phase. As volume fraction of γ{sup '} precipitates is small (<10%) for Inconel 718, the compositional fluctuations caused by its dissolution are low. The measured length

  15. Short circuit - How our power supply became more expensive and got worse. A critical balance after eight years ''deregulation'' of the German Energy Economy; Kurzschluss - Wie unsere Stromversorgung teurer und schlechter wurde. Eine kritische Bilanz nach acht Jahren ''Liberalisierung'' der deutschen Energiewirtschaft

    Energy Technology Data Exchange (ETDEWEB)

    Leuschner, U.

    2007-07-01

    verursachte. Wie Leuschner feststellt, waere der Schaltungsfehler der EON-Netzleitstelle Lehrte vor ein paar Jahren noch vom System toleriert worden. Er habe nur deshalb so gravierende Folgen haben koennen, weil das UCTE-Netz inzwischen durch den Stromhandel und andere Folgen der Deregulierung bis an die Grenzen seiner Kapazitaet belastet sei. Im dritten Teil (''Netznutzung und Netzentgelte'') beleuchtet er in einem zusaetzlichen Kapitel die Bemuehungen der EU-Kommission, doch noch die Rahmenbedingungen fuer echten Wettbewerb herzustellen. Die neueste Forderung der Kommission nach eigentumsmaessiger Entflechtung der Netze deutet er als ''Flucht nach vorn'' angesichts der Tatsache, dass in saemtlichen EU-Laendern seit der Liberalisierung die Strompreise gestiegen sind und das zum Teil sogar ueber die Haelfte (mit der einzigen Ausnahme Englands, und hier auch nur der Haushaltsstrompreise). Kraeftig erweitert hat der Verfasser auch den vierten Teil zum Thema ''Management und Politik'': Zum einen findet man hier nun beschrieben, wie Ex-Bundeskanzler Gerhard Schroeder einen Spitzenjob beim russischen Energiekonzern Gazprom erhielt, dem er bereits in seiner Amtszeit als Bundeskanzler politisch behilflich war, und wie sein ehemaliger Wirtschaftsminister Wolfgang Clement in den Aufsichtsrat von RWE Power einziehen durfte. Zum anderen wird ein kritischer Blick auf die Werbekampagnen geworfen, mit denen die Energiekonzerne versuchen, ihr Erscheinungsbild in der Oeffentlichkeit aufzuhellen und den Energieverbrauchern ein X fuer ein U vorzumachen. (orig.)

  16. Sprachvermittlung und Spracherwerb in Afrika. Deutsch nach ...

    African Journals Online (AJOL)

    Teaching foreign languages in a multilingual context, such as one finds in South African schools, poses unique questions. The theory that pedagogically underpins and articulates the value of the study of foreign languages is internationally established and thus also valid in the South African context. Nevertheless, one has ...

  17. Ellbogen- und Handgelenksendoprothetik beim Rheumatiker - Richtlinien und Rehabilitation

    Directory of Open Access Journals (Sweden)

    Chochole M

    2008-01-01

    Full Text Available Die Endoprothetik an Ellbogen und Handgelenk ist seit etwa drei Jahrzehnten etabliert. An beiden Gelenken haben sich einzelne Implantate oder Designs durchgesetzt. Operationstechniken und Nachuntersuchungsergebnisse sind publiziert. Wenig ist jedoch zum Thema Nachbehandlung und Nachsorge veröffentlicht. Diese Arbeit beschäftigt sich detailliert mit der ärztlichen und therapeutischen Betreuung nach Implantation einer Ellbogen- oder Handgelenksendoprothese beim Patienten mit rheumatischer Arthritis unter Aufgliederung in Krankenhausaufenthalt, ambulanter Nachsorge sowie stationärer Rehabilitation. Dabei werden Zeitrahmen, Therapieziele und Behandlungen gesondert angeführt.

  18. Zuwanderung nach Österreich. Integrationspolitische Herausforderungen

    Directory of Open Access Journals (Sweden)

    Heinz Faßmann

    2016-12-01

    Full Text Available ENGLISH: Since the early 1960ies, Austria has become an immigration country against its will. In the beginning, the migration of Guestworkerswas a flexible supplement of the national labour market. Gradually it developed towards a permanent immigration.With the accession to the European Union Austria became a part of the common European migration era. The immigration fromthird countries lost importance, the immigration from other member states gained. Beside, Austria was always a target countryfor asylum seekers. The structural characteristics of the immigrants as well as the historical context showed some changes. Therefore,the integration processes happened differently. While the integration of the immigrants from other member states –especially from Germany – performed conflict – free and quick, the integration of the guestworkers and their descendants proceededonly stepwise. A similar stepwise and long lasting integration process can be expected for the asylum seekers due totheir qualification and their cultural background. Therefore, the cultural diversity will increase and it is not always an enrichmentonly, but also a reason of conflicts about the valid societal perspectives. DEUTSCH: Österreich hat sich seit den 1960er zu einem Einwanderungsland wider Willen entwickelt. Anfangs war die Zuwanderung vonGastarbeiterInnen eine flexible Ergänzung des nationalen Arbeitsmarktes. Nach und nach entwickelte sich daraus aber eine dauerhafteZuwanderung. Mit dem Beitritt zur Europäischen Union wurde Österreich auch Teil eines Europäischen Wanderungsraums.Die Zuwanderung aus den Drittstaaten verlor an Bedeutung, die Zuwanderung aus anderen Mitgliedstaaten der EuropäischenUnion wurde wichtiger. Daneben war Österreich auch immer wieder Aufnahmeland von Asylwerbern. Die strukturellenMerkmale der Zugewanderten und der zeitliche Kontext der Zuwanderung waren ungleich. Daher verliefen auch die Integrationsprozessesehr unterschiedlich. W

  19. Gosvig und das Problem der Geschichte

    DEFF Research Database (Denmark)

    Wentzer, Thomas Schwarz

    2016-01-01

    Der Essay geht der Frage nach, wieso so viele philosophische Bücher, insbesondere innerhalb der sogenannten 'kontinentalen' Philosophie des 20. Jhs, einen Titel tragen, der durch die Struktur 'x und y' gekennzeichnet ist. Hat Heideggers 'Sein und Zeit' auch hier Schule gemacht? Wenn ja, wie so? U...... These, dass die Iteration des 'und' tatsächlich und in Kontrast zur Genetivkonstruktion der Idealisten ('Phänomenologie des Geistes') die Geschichtlichkeit im Zeitalter postsubjektivistischen Denkens reflektiert....

  20. Modeling of DNA damage-cluster, cell-cycle and repair pathway dependent radiosensitivity after low- and high-LET irradiation; Modellierung der DNA-Schadenscluster-, Zellzyklus- und Reparaturweg-abhaengigen Strahlenempfindlichkeit nach niedrig- und hoch-LET-Bestrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, Paul

    2017-07-17

    irradiation. This method is able to qualitatively predict the influence of the cell-cycle and the radiation quality on radiosensitivity. Based on this, two approaches for the LEM prediction of the Relative Biological Effectiveness (RBE) are compared. The first approach predicts the RBE based on the survival of asynchronous cells. The second approach predicts the RBE from the sum of survival curves of the subpopulations, which contribute to the asynchronous cell population. Both approaches lead to qualitatively similar results. In the context of describing the microscopic dose deposition of ion irradiation by the amorphous track structure, two questions are addressed: 1. Is it possible to improve the prediction of cell survival after ion irradiation by a more sophisticated composition of the direct and indirect effect? 2. is the amorphous track structure an appropriate model of the dose deposition regarding the DNA damage clustering on the nm-scale or is it necessary to evaluate single ionizations on the molecular level? Regarding the first question, it is shown that a more detailed evaluation of the direct and indirect effect improves the agreement of the LEM predictions to data. Concerning the second question, it is shown that the amorphous track structure can be used for the prediction of DNA damage induction on the nm-scale similar to an ab initio Monte Carlo simulation. In the context of cell-survival modeling, the relevant length scale for DNA damage-clustering is often discussed. The iDSBs und cDSBs used in the GLOBLE and LEM are referring to DNA damage clustering on the μm-scale. There are also models which predict the cell survival after ion irradiation based on complex DNA-damage-clusters on the nm-scale. This work shows, that complex DNA damage-clusters on the μm-scale are correlated to damage clusters on the nm-scale. Therefore, it is possible to predict the cell survival after ion irradiation based on both scales. However, the cell survival after photon

  1. Dissociative sticking of CH4 on Ru(0001)

    DEFF Research Database (Denmark)

    Nielsen, Jane Hvolbæk; Holmblad, Peter Mikal; Chorkendorff, Ib

    1999-01-01

    In this study the CH4 dissociation probability on Ru(0001) is found for various translational and vibrational energies. The absolute sticking values are determined from King and Wells experiments and carbon uptake curves. The carbon amount is determined from the recombination signal of carbon...... with oxygen obtained after the beam exposure when heating in an oxygen atmosphere. The measured sticking coefficient of CH4 is strongly enhanced both by increasing the translational and the vibrational energy of the CH4 molecule. A model is applied to the data and an estimate of the thermal activation energy...

  2. Vom Sprechen des Unsagbaren und vom Sehen des Unsichtbaren oder die essayistische Suche nach der verlorenen Ganzheit On Speaking about the Unspeakable and Seeing the Invisible or: The Search for Lost Entirety

    Directory of Open Access Journals (Sweden)

    Maria Marchetta

    2002-03-01

    Full Text Available Christina Scherer weist in ihrer Dissertation die strukturelle Äquivalenz zwischen einer essayistischen Filmästhetik und dem Prozess des Erinnerns auf. Ivens, Marker, Godard und Jarman thematisieren in und mit ihren Filmen die Unverfügbarkeit der Erinnerung und halten trotz ihres Zweifels an der Abbildbarkeit von Welt und ihrer Einsicht in die Uneinholbarkeit der Vergangenheit den Horizont der Möglichkeit von Erinnerung offen. In Essayfilmen sind es vor allem die selbstreflexive Selbstvergewisserung, die Einsicht in das unausweichliche Verfehlen der Vergangenheit und der melancholische Rückblick auf eine verloren gegangene Ganzheit, die einen fühlenden Verstand und ein denkendes Herz generieren.Christina Scherer’s dissertation points to the structural equivalence between the aesthetics of the essay film and the process of remembering. Ivens, Marker, Godard and Jarman make the unavailability of memory their central theme. Despite the filmmakers’ doubts about the possibility of replicating a true image of the world and their knowledge of the irretrievability of the past they nonetheless insist on the possibility of memory. Reflectively positioning oneself, acknowledging inevitable errors of the past, and looking back in melancholy on a lost entirety are some of the strategies in essay films which generate a sympathetic mind and a thinking heart.

  3. High Resolution CH4 Emissions and Dissolved CH4 Measurements Elucidate Surface Gas Exchange Processes in Toolik Lake, Arctic Alaska

    Science.gov (United States)

    Del Sontro, T.; Sollberger, S.; Kling, G. W.; Shaver, G. R.; Eugster, W.

    2013-12-01

    Approximately 14% of the Alaskan North Slope is covered in lakes of various sizes and depths. Diffusive carbon emissions (CH4 and CO2) from these lakes offset the tundra sink by ~20 %, but the offset would substantially increase if ebullitive CH4 emissions were also considered. Ultimately, arctic lake CH4 emissions are not insignificant in the global CH4 budget and their contribution is bound to increase due to impacts from climate change. Here we present high resolution CH4 emission data as measured via eddy covariance and a Los Gatos gas analyzer during the ice free period from Toolik Lake, a deep (20 m) Arctic lake located on the Alaskan North Slope, over the last few summers. Emissions are relatively low (Gatos gas analyzer. Thus, having both the flux and the CH4 gradient across the air-water interface measured directly, we can calculate k and investigate the processes influencing CH4 gas exchange in this lake. Preliminary results indicate that there are two regimes in wind speed that impact k - one at low wind speeds up to ~5 m s-1 and another at higher wind speeds (max ~10 m s-1). The differential wind speeds during night and day may compound the effect of convective mixing and cause the diurnal variation in observed fluxes.

  4. Das Sabbatjahr für Lehrerinnen und Lehrer: Wer profitiert und in welcher Form?

    OpenAIRE

    Rothland, Martin

    2013-01-01

    Das Sabbatjahr für Lehrerinnen und Lehrer wird programmatisch als Maßnahme der Belastungsreduktion, der Regeneration sowie der Ressourcenstärkung diskutiert. Empirische Belege für die erwarteten Effekte finden sich jedoch kaum. Im Rahmen einer Längsschnittstudie mit drei Erhebungszeitpunkten vor, während und nach dem Sabbatjahr werden die Entwicklung der Belastungswahrnehmung, des Gesundheitszustands und allgemeiner sowie arbeitsbezogener Emotionen (Berufs- und Lebenszufriedenheit) auf der Ba...

  5. Raman spectroscopy measurement of CH4 gas and CH4 dissolved in water for laser remote sensing in water

    Science.gov (United States)

    Somekawa, Toshihiro; Fujita, Masayuki

    2018-04-01

    We examined the applicability of Raman spectroscopy as a laser remote sensing tool for monitoring CH4 in water. The Raman technique has already been used successfully for measurements of CO2 gas in water. In this paper, considering the spectral transmittance of water, third harmonics of Q-switched Nd:YAG laser at 355 nm (UV region) was used for detection of CH4 Raman signals. The Raman signal at 2892 cm-1 from CH4 dissolved in water was detected at a tail of water Raman signal.

  6. δ13C-CH4 in ice core samples

    DEFF Research Database (Denmark)

    Sperlich, Peter

    Ice core records of δ13C-CH4 reflect the variability of CH4 biogeochemistry in response to climate change and show this system is far more complex than expected. The first part of this work is concerned with the development of analytical techniques that allow 1) precise referencing and 2) measure......Ice core records of δ13C-CH4 reflect the variability of CH4 biogeochemistry in response to climate change and show this system is far more complex than expected. The first part of this work is concerned with the development of analytical techniques that allow 1) precise referencing and 2......) measurements of δ13C-CH4 in ice core samples as is required when δ13C-CH4 records that are measured in several laboratories are merged for analysis. Both the referencing and measurement techniques have been compared to further laboratories which proofed the accuracy of the analytical systems. The second part...

  7. Aufgabenspektrum, Ausgestaltung und Geschäftsmodelle von E-Learning-Einrichtungen an Hochschulen

    OpenAIRE

    Bremer, Claudia; Eichhorn, Michael

    2015-01-01

    Im Rahmen des Projektes „Uni:prise – Universities as Enterprises“ wurden Geschäftsmodelle und Transferbeziehungen an Hochschulen untersucht und dabei auch speziell die Leistungen und Transferbeziehungen von Zentren und Einrichtungen an Hochschulen und Universitäten insbesondere aus dem Bereich E-Learning in den Blick genommen. Als Richtschnur für die Untersuchung diente dem Gesamtprojekt (Gaus & Raith, 2013) der Business Model Canvas nach Osterwalder und Pigneur (2009) mit neun Teilaspekten, ...

  8. Zur Materialfrage in der Implantatchirurgie des Deszensus: Vergleich zwischen Polypropylenvlies und dermaler porciner azellulärer Kollagenmatrix unter Berücksichtigung der Erfahrungen nach 7 Jahren Anwendung von Implantaten

    Directory of Open Access Journals (Sweden)

    Fischer A

    2004-01-01

    Full Text Available Ziel der Studie: Die Studie beschreibt Verwendung, Effektivität und Nebenwirkungen zwei verschiedener Implantate, die in der Senkungschirurgie verwendet werden und stellen die Ergebnisse in einen Zusammenhang mit den Erfahrungen mit anderen Implantaten seitens der Autoren und in der Literatur. Material und Methode: 180 Patientinnen mit verschiedenen Formen von Genitalprolaps werden mit Biomesh(R behandelt, 185 Patientinnen mit Pelvicol(R in der Zeit von Juli 2000 bis Dezember 2002. Die Ergebnisse werden verglichen. Ergebnisse: Die Verwendung von Implantaten ist häufig erforderlich, vor allen Dingen in Fällen eines stark zerstörten Beckenbodensystems oder bei Rezidiven. Die Verwendung von Netz-Implantaten in der Senkungschirurgie ist sicher, solange eine vernünftige Implantatstruktur zugrunde liegt. Beide in dieser Studie untersuchten Implantate erfüllen dies zufriedenstellend. Rezidiv- und Senkungszustände der benachbarten Kompartimente müssen getrennt ausgewertet werden, um eine Verwechslung zwischen einem schlechten Therapieergebnis (obwohl es eigentlich gut ist und Strukturschwächen in den (noch nicht behandelten Kompartimenten nicht in einem Topf zu werfen. Die Notwendigkeit einer Explantation, das Ausbilden von Abszessen oder die Abstoßungsreaktion wurden nur gesehen, wenn multifilamente mikroporöse Bänder oder entsprechend strukturiertes Nahtmaterial zur gleichen Zeit eingesetzt worden sind, oder wenn Blutergußbildung nicht durch subtile Hämostase während des Eingriffs unterdrückt werden konnte. Schlußfolgerung: Beide Materialien (Biomesh(R und Pelvicol(R liefern in der Verwendung bei implantatunterstützter Deszensus-Chirurgie gute Ergebnisse, gleich, wo sie auch eingesetzt werden. Es gibt keine signifikanten Unterschiede in der Effektivität oder in der Nebenwirkungsrate. Es bedarf nun der größer angelegten multizentrischen Studien, um alloplastisch unterstützte rekonstruktive Beckenbodenchirurgie nicht nur in den

  9. The Drivers of the CH4 Seasonal Cycle in the Arctic and What Long-Term Observations of CH4 Imply About Trends in Arctic CH4 Fluxes

    Science.gov (United States)

    Sweeney, C.; Karion, A.; Bruhwiler, L.; Miller, J. B.; Wofsy, S. C.; Miller, C. E.; Chang, R. Y.; Dlugokencky, E. J.; Daube, B.; Pittman, J. V.; Dinardo, S. J.

    2012-12-01

    The large seasonal change in the atmospheric column for CH4 in the Arctic is driven by two dominant processes: transport of CH4 from low latitudes and surface emissions throughout the Arctic region. The NOAA ESRL Carbon Cycle Group Aircraft Program along with the NASA funded Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) have initiated an effort to better understand the factors controlling the seasonal changes in the mole fraction of CH4 in the Arctic with a multi-scale aircraft observing network in Alaska. The backbone of this network is multi-species flask sampling from 500 to 8000 masl that has been conducted every two weeks for the last 10 years over Poker Flat, AK. In addition regular profiles at the interior Alaska site at Poker Flat, NOAA has teamed up with the United States Coast Guard to make profiling flights with continuous observations of CO2, CO, CH4 and Ozone between Kodiak and Barrow every 2 weeks. More recently, CARVE has significantly added to this observational network with targeted flights focused on exploring the variability of CO2, CH4 and CO in the boundary layer both in the interior and the North Slope regions of Alaska. Taken together with the profiling of HIAPER Pole-to-Pole Observations (HIPPO), ground sites at Barrow and a new CARVE interior Alaska surface site just north of Fairbanks, AK, we now have the ability to investigate the full evolution of the seasonal cycle in the Arctic using both the multi-scale sampling offered by the different aircraft platforms as well as the multi-species sampling offered by in-situ and flask sampling. The flasks also provide a valuable tie-point between different platforms so that spatial and temporal gradients can be properly interpreted. In the context of the seasonal cycle observed by the aircraft platforms we will look at long term ground observations over the last 20 years to assess changes in Arctic CH4 emissions which have occurred as a result of 0.6C/decade changes in mean surface

  10. Sacherschliessung nach RDA

    Directory of Open Access Journals (Sweden)

    Hans Schürmann

    2015-05-01

    Full Text Available Die Resource Description and Access (RDA wird für den deutschsprachigen Raum das neue Regelwerk für die bibliothekarische Erschliessung der Bestände. In diesem Regelwerk wird auch die Sacherschliessung neu geregelt. Zurzeit sind diese Seiten noch leer. Doch wie soll ein Regelwerk für die Sacherschliessung aussehen? Kriterien für eine Regelung fehlen, zu stark hat sich das Umfeld der Inhaltserschliessung in den letzten Jahren geändert. Auch von der Schlagworttheorie her sind noch keine Hinweise in Sicht. Deshalb wird in verschiedenen Gremien intensiv diskutiert, wie eine zukunftsfähige Sacherschliessung aussehen könnte. In welchem Rahmen bewegt sich die Diskussion und woran soll sich die Regelwerksentwicklung für den Sachkatalog orientieren? Der Beitrag erwägt zwischen der Sachkataloggeschichte einerseits und dem modernen Datenmanagement im Netz andererseits die Bedeutung und die Rolle eines Sacherschliessungsregelwerks. Resource Description and Access (RDA will be the new standard for descriptive cataloguing in the German-speaking countries. Under RDA, subject indexing will also be redefined, although, at present, the relevant pages remain blank. This article ponders the question what these new standards could look like. As yet no clear criteria have emerged – the field of subject indexing has undergone too much change in recent years for that. Nor does the theory appear to offer any answers at the moment. There is therefore intensive and ongoing debate in the various forums. What is the framework of these discussions and what are the key criteria? The article summarizes them and considers the importance of indexing standards in the light of both the history of indexing and modern data management on the web.

  11. Vibrational transition moments of CH4 from first principles

    Science.gov (United States)

    Yurchenko, Sergei N.; Tennyson, Jonathan; Barber, Robert J.; Thiel, Walter

    2013-09-01

    New nine-dimensional (9D), ab initio electric dipole moment surfaces (DMSs) of methane in its ground electronic state are presented. The DMSs are computed using an explicitly correlated coupled cluster CCSD(T)-F12 method in conjunction with an F12-optimized correlation consistent basis set of the TZ-family. A symmetrized molecular bond representation is used to parameterise these 9D DMSs in terms of sixth-order polynomials. Vibrational transition moments as well as band intensities for a large number of IR-active vibrational bands of 12CH4 are computed by vibrationally averaging the ab initio dipole moment components. The vibrational wavefunctions required for these averages are computed variationally using the program TROVE and a new ‘spectroscopic’ 12CH4 potential energy surface. The new DMSs will be used to produce a hot line list for 12CH4.

  12. Macromolecule simulation and CH4 adsorption mechanism of coal vitrinite

    Science.gov (United States)

    Yu, Song; Yan-ming, Zhu; Wu, Li

    2017-02-01

    The microscopic mechanism of interactions between CH4 and coal macromolecules is of significant practical and theoretical importance in CBM development and methane storage. Under periodic boundary conditions, the optimal energy configuration of coal vitrinite, which has a higher torsion degree and tighter arrangement, can be determined by the calculation of molecular mechanics (MM) and molecular dynamics (MD), and annealing kinetics simulation based on ultimate analysis, 13C NMR, FT IR and HRTEM. Macromolecular stabilization is primarily due to the van der Waals energy and covalent bond energy, mainly consisting of bond torsion energy and bond angle energy. Using the optimal configuration as the adsorbent, GCMC simulation of vitrinite adsorption of CH4 is conducted. A saturated state is reached after absorbing 17 CH4s per coal vitrinite molecule. CH4 is preferentially adsorbed on the edge, and inclined to gathering around the branched chains of the inner vitrinite sites. Finally, the adsorption parameters are calculated through first principle DFT. The adsorbability order is as follows: aromatic structure> heteroatom rings > oxygen functional groups. The adsorption energy order is as follows: Top graphene. However, the energy of the most preferential location is much lower than that of graphite/graphene. CH4 is more easily absorbed on the surface of vitrinite. Adsorbability varies considerably at different adsorption locations and sites on the surface of vitrinite. Crystal parameter of vitrinite is a = b = c = 15.8 Å and majority of its micropores are blow 15.8 Å, indicating that the vitrinite have the optimum adsorption aperture. It can explain its higher observed adsorption capacities for CH4 compared with graphite/graphene.

  13. Use of residual fuels and biowaste of low calorific value for syngas production by the Noell conversion process; Der Einsatz niederkaloriger Energietraeger aus Reststoffen und Bioabfaellen zur Synthesegaserzeugung nach dem Noell-Konversionsverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Schingnitz, M.; Goehler, P. [Noell-KRC Energie- und Umwelttechnik GmbH, Freiberg (Germany)

    1996-12-31

    By gasification with oxygen, municipal waste can be converted into a pure, burnable gas. The gas can be used like natural gas, e.g. in boilers and industrial furnaces, gas engines and gas turbines for heat and electric power generation, but also in chemical synthesis processes, e.g. methanol synthesis. If the right gasification technology is selected, the mineral constitutents of the waste materials can be melted down at the same time, e.g. into a granulate with a glass-like structure that can be used as constructional material. (orig) [Deutsch] Durch Vergasung mit Sauerstoff lassen sich kommunale Abfaelle in ein brennbares Gas umwandeln. Dieses Gas kann mit einfachen und bewaehrten verfahren von Schadstoffen wie Schwefelverbindungen befreit werden. Es laesst sich wie sauberes Erdgas umweltfreundlich in Kesseln und Industrieoefen einsetzen, in Gasmotoren oder Gasturbinen zur Erzeugung von Elektroenergie und Heizwaerme nutzen, aber auch zu chemischen Synthesen, beispielsweise von Methanol, verwenden. Bei geeigneter Wahl der Vergasungstechnologie gelingt es ausserdem, die mineralischen Bestandteile der Abfallstoffe prozessintern aufzuschmelzen und in ein beispielsweise als Baustoff verwertbares Schmelzgranulat mit glasartiger Struktur zu ueberfuehren. (orig)

  14. Use of residual fuels and biowaste of low calorific value for syngas production by the Noell conversion process; Der Einsatz niederkaloriger Energietraeger aus Reststoffen und Bioabfaellen zur Synthesegaserzeugung nach dem Noell-Konversionsverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Schingnitz, M; Goehler, P [Noell-KRC Energie- und Umwelttechnik GmbH, Freiberg (Germany)

    1997-12-31

    By gasification with oxygen, municipal waste can be converted into a pure, burnable gas. The gas can be used like natural gas, e.g. in boilers and industrial furnaces, gas engines and gas turbines for heat and electric power generation, but also in chemical synthesis processes, e.g. methanol synthesis. If the right gasification technology is selected, the mineral constitutents of the waste materials can be melted down at the same time, e.g. into a granulate with a glass-like structure that can be used as constructional material. (orig) [Deutsch] Durch Vergasung mit Sauerstoff lassen sich kommunale Abfaelle in ein brennbares Gas umwandeln. Dieses Gas kann mit einfachen und bewaehrten verfahren von Schadstoffen wie Schwefelverbindungen befreit werden. Es laesst sich wie sauberes Erdgas umweltfreundlich in Kesseln und Industrieoefen einsetzen, in Gasmotoren oder Gasturbinen zur Erzeugung von Elektroenergie und Heizwaerme nutzen, aber auch zu chemischen Synthesen, beispielsweise von Methanol, verwenden. Bei geeigneter Wahl der Vergasungstechnologie gelingt es ausserdem, die mineralischen Bestandteile der Abfallstoffe prozessintern aufzuschmelzen und in ein beispielsweise als Baustoff verwertbares Schmelzgranulat mit glasartiger Struktur zu ueberfuehren. (orig)

  15. Lew Kopelew - der Schriftsteller und Wissenschaftler, der Freund der Menschen und Verfechter ihrer Grundrechte

    OpenAIRE

    Keller, Werner

    2010-01-01

    Unsere Erwartung war anders als sonst – freudig, doch nicht frei von Erregung und leiser Furcht: Wird man im Kreml das gegebene Wort halten und nach einem Jahr die Rückkehr in die russische Heimat erlauben? Als Gast Heinrich Bölls kam Lew Kopelew im November 1980 nach Deutschland. In der Bonner Wohnung des Slawisten Wolfgang Kasack konnte ich mich ihm wenige Tage später vorstellen: Er war groß, von beeindruckender Physiognomie – nicht nur durch den Prophetenbart –, allerdings fast bleich und ...

  16. Renewable energy based catalytic CH4 conversion to fuels

    NARCIS (Netherlands)

    Baltrusaitis, Jonas; Jansen, I.; Schuttlefield, J.D.S.

    2014-01-01

    Natural gas is envisioned as a primary source of hydrocarbons in the foreseeable future. With the abundance of shale gas, the main concerns have shifted from the limited hydrocarbon availability to the sustainable methods of CH4 conversion to fuels. This is necessitated by high costs of natural gas

  17. CO2/CH4 Separation via Polymeric Blend Membrane

    Directory of Open Access Journals (Sweden)

    H. Sanaeepur

    2013-01-01

    Full Text Available CO2/CH4 gas separation is a very important applicatable process in upgrading the natural gas and landfil gas recovery. In this work, to investigate the membrane separation process performance, the gas permeation results andCO2/CH4 separation characteristics of different prepared membranes (via blending different molecular weights of polyethylene glycol (PEG as a modifier with acrylonitrile-butadiene-styrene (ABS as a backbone structure have been studied. Furthermore, SEM analysis was carried out for morphological investigations. The effect of PEG content on gas transport properties on the selected sample was also studied. The effect of pressure on CO2 permeation was examined and showed that at the pressure beyond 4 bar, permeability is not affected by pressure. The results showed that more or less in all cases, incorporation of PEG molecules without any significant increase in CH4 permeability increases the CO2/CH4 selectivity. From the view point of gas separation applications the resultant data are within commercial attractive range

  18. Person, Profil, Privatheit. Die Suche nach Eigennamen als informationsethisches Problem

    OpenAIRE

    Bordat, Josef

    2005-01-01

    Zusammenfassung: Der Schutz der Privatsphäre im Rahmen der Nutzung von Internet-Suchmaschinen wird auf der Ebene der privacy als Recht auf wirksamen Schutz seiner Daten und der Privatheit als Recht des "Für-Sich-Seins", auf "solitude, anonymity and intimacy" sowie auf "control of personal information" untersucht. Gerade letztere gerät im Zusammenhang mit der Suche nach Eigennamen in Gefahr, da im Ergebnis über persönliche Daten verfügt wird, ohne das die betreffende Person weiß, wer zu wel...

  19. Cuts in energy and operating cost with the Swiss system 'Energie in ARA' - practical experience in Germany; Energie- und Betriebskosteneinsparungen nach dem schweizerischen System ''Energie in ARA'' - Praxiserfahrungen in Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Christmann, B. [UmBAUwelt Partnerschaft Architekten und Ingenieure, Riedstadt (Germany)

    1999-07-01

    German sewage treatment plants, too, have potential for saving energy cost and cutting down on their operating expenditure. Following the systematy developed by the 'Energie in ARA' concept, this potential can be harnessed. (orig.) [German] Potential fuer Energiekosteneinsparungen und dadurch initiierte Betriebskosteneinsparungen ist auch bei deutschen Klaeranlagen vorhanden. Die Systematik 'Energie in ARA' kann fuer die Erschliessung der Einsparpotentiale verwendet werden. (orig.)

  20. Simulasi Numeris Karakteristik Pembakaran CH4/CO2/Udara dan CH4/CO2/O2 pada Counterflow Premixed Burner

    Directory of Open Access Journals (Sweden)

    Hangga Wicaksono

    2017-08-01

    Full Text Available The high amount of CO2 produced in a conventional biogas reactor needs to be considered. A further analysis is needed in order to investigate the effect of CO2 addition especially in thermal and chemical kinetics aspect. This numerical study has been held to analyze the effect of CO2 in CH4/CO2/O­2 and CH4/CO2/Air premixed combustion. In this study one dimensional analisys in a counterflow burner has been performed. The volume fraction of CO2 used in this study was 0%-40% from CH4’s volume fraction, according to the amount of CO2 in general phenomenon. Based on the flammability limits data, the volume fraction of CH4 used was 5-61% in O2 environment and 5-15% in air environment. The results showed a decreasing temperature along with the increasing percentage of CO2 in each mixtures, but the effect was quite smaller especially in stoichiometric and lean mixture. CO2 could affects thermally (by absorbing heat due to its high Cp and also made the production of unburnt fuel species such as CO relatively higher.

  1. The effects of CO addition on the autoignition of H-2, CH4 and CH4/H-2 fuels at high pressure in an RCM

    NARCIS (Netherlands)

    Gersen, Sander; Darmeveil, Harry; Levinsky, Howard

    2012-01-01

    Autoignition delay times of stoichiometric and fuel-lean (phi = 0.5) H-2, H-2/CO, CH4, CH4/CO, CH4/H-2 and CH4/CO/H-2 mixtures have been measured in an Rapid Compression Machine at pressures ranging from 20 to 80 bar and in the temperature range 900-1100K. The effects of CO addition on the ignition

  2. On the use of satellite-derived CH4 : CO2 columns in a joint inversion of CH4 and CO2 fluxes

    NARCIS (Netherlands)

    Pandey, S.

    2015-01-01

    We present a method for assimilating total column CH4 : CO2 ratio measurements from satellites for inverse modeling of CH4 and CO2 fluxes using the variational approach. Unlike conventional approaches, in which retrieved CH4 : CO2 are multiplied by model-derived total column CO2 and only the

  3. Experimental ion mobility measurements in Xe-CH4

    Science.gov (United States)

    Perdigoto, J. M. C.; Cortez, A. F. V.; Veenhof, R.; Neves, P. N. B.; Santos, F. P.; Borges, F. I. G. M.; Conde, C. A. N.

    2017-09-01

    Data on ion mobility is important to improve the performance of large volume gaseous detectors. In the present work, the method, experimental setup and results for the ion mobility measurements in Xe-CH4 mixtures are presented. The results for this mixture show the presence of two distinct groups of ions. The nature of the ions depend on the mixture ratio since they are originated by both Xe and CH4. The results here presented were obtained for low reduced electric fields, E/N, 10-25 Td (2.4-6.1 kV ṡ cm-1 ṡ bar-1), at low pressure (8 Torr) (10.6 mbar), and at room temperature.

  4. Ion irradiation of CH4-containing icy mixtures

    International Nuclear Information System (INIS)

    Baratta, G.A.; Domingo, M.; Ferini, G.; Leto, G.; Palumbo, M.E.; Satorre, M.A.; Strazzulla, G.

    2003-01-01

    We have studied by infrared absorption spectroscopy the effects of ion irradiation with 60 keV Ar 2+ ions on pure methane (CH 4 ) ice at 12 K and mixtures with water (H 2 O) and nitrogen (N 2 ). Ion irradiation, among other effects, causes the rupture of original molecular bonds and the formation of molecular species not present in the initial ice. Here we present the experimental results and discuss their astrophysical relevance

  5. Preparation of CH4 for 14C measurements

    International Nuclear Information System (INIS)

    Cechova, A.; Grgula, M.; Povinec, P.; Sivo, A.

    1988-01-01

    An improved method of methane preparation from wood samples is described. It consists of the preparation of α-cellulose to secure a complete removal of contamination from the wood, its combustion to the form of CO 2 and the preparation of CH 4 in a new designed hydrogenation converter. Purified methane is suitable as a gas filling of the proportional counter. (author). 1 fig., 16 ref

  6. CH4 emissions from enteric fermentation in Austria

    International Nuclear Information System (INIS)

    Gebetsroither, E.; Orthofer, R.; Strebl, F.

    2002-07-01

    This report contains the results of an inventory for methane (CH 4 ) emissions from agricultural enteric fermentation in Austria for the period 1980-2001. Emissions were calculated according to IPCC guidelines. The detailed IPCC 'Tier 2' methodology was applied for cattle (which contribute the vast majority of emissions). The 'Tier 2' methodology relies on specific emission factors that are calculated from the energy intake for different cattle farming practices. The less detailed 'Tier 1' methodology was applied for all other animal categories. Emissions from organic and conventional farming practices were calculated separately. Results indicate that CH 4 emissions from manure management have increased from 1980 to a peak in 1984-1985, and since then have steadily declined. CH 4 emissions were about 169.300 t/yr in 'Kyoto' base year 1990 and have since declined by about 11 % to about 150.000 t/yr in 2001. Almost all emissions (95 % in 1990 and 94 % in 2001) are caused by cattle farming. The contribution of 'dairy cattle' to all emissions from cattle was 49 % in 1990, and has declined to 43 % in 2001. The overall reduction was caused mainly by a decrease in the total numbers of animals. However, in the case of dairy cows the reduction of animals is partly counterbalanced by an increase in emissions per animal (because of the increasing gross energy intake and milk production of milk cattle since 1990). Uncertainties of emissions were estimated with a 'Monte Carlo' simulation. Assuming a normal probability distribution, the calculated standard deviation is 4 %. This indicates there is a 95 % probability that CH 4 emissions are between ± 2 standard deviations, i.e. between 153.000 t and 178.000 t in the year 1990 and between 138.000 t and 162.000 t in the year 2001. (author)

  7. Thermodynamic and hydrochemical controls on CH4 in a coal seam gas and overlying alluvial aquifer: new insights into CH4 origins

    OpenAIRE

    Owen, D. Des. R.; Shouakar-Stash, O.; Morgenstern, U.; Aravena, R.

    2016-01-01

    Using a comprehensive data set (dissolved CH4, ?13C-CH4, ?2H-CH4, ?13C-DIC, ?37Cl, ?2H-H2O, ?18O-H2O, Na, K, Ca, Mg, HCO3, Cl, Br, SO4, NO3 and DO), in combination with a novel application of isometric log ratios, this study describes hydrochemical and thermodynamic controls on dissolved CH4 from a coal seam gas reservoir and an alluvial aquifer in the Condamine catchment, eastern Surat/north-western Clarence-Moreton basins, Australia. ?13C-CH4 data in the gas reservoir (?58? to ?49?) and sha...

  8. Body weight gain after radioiodine therapy of hyperthyroidism; Koerpergewichtsentwicklung nach Radioiodtherapie einer Hyperthyreose

    Energy Technology Data Exchange (ETDEWEB)

    Scheidhauer, K.; Odatzidu, L.; Schicha, H. [Koeln Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Kiencke, P. [Koeln Univ. (DE). Inst. fuer Medizinische Statistik, Informatik und Epidemiologie (IMSIE)

    2002-02-01

    Aim: Analysis and follow up of body weight after radioiodine therapy (RITh) of hyperthyroidism, since excessive weight gain is a common complaint among these patients. Methods: Therapy and body weight related data of 100 consecutive RITh-patients were retrospectively analysed from the time before up to three years after RITh. All patients suffered from hyperthyroidism (Graves' disease or autonomy), but were adjusted to euthyroid levels after RITh. Patients' data were compared to a control group of 48 euthyroid patients out of the same ambulance and during the same time scale. Results: All patients (RITh and controls) gained weight over the time. There was no statistically significant difference in BMI development over three years between RITh-patients and controls (5.5% resp. 4.9% increase). In the first year after RITh, weight gain of the RITh patients was higher indeed, but lower in the follow up, resulting in the same range of weight gain after three years as the controls. Besides that women showed a slightly higher increase of BMI than men, and so did younger patients compared to elder as well as patients with overweight already before RITh. Conclusions: An initially distinct increase of body weight after RITh of hyperthyroidism is mainly a compensation of pretherapeutic weight loss due to hyperthyroidism. Presupposing adequate euthyroid adjustment of thyroid metabolism after therapy, RITh is not responsible for later weight gain and adipositas. (orig.) [German] Ziel: Untersuchung der Entwicklung des Koerpergewichtes nach {sup 131}I-Therapie einer Hyperthyreose, da der Radioiodtherapie (RITh) haeufig eine exzessive posttherapeutische Gewichtszunahme angelastet wird. Methoden: Retrospektiv wurden therapie- und koerpergewichtsbezogene Daten von 100 konsekutiven Patienten vor und bis drei Jahre nach RITh einer Hyperthyreose (Morbus Basedow oder funktionelle Autonomie) erfasst und mit denen einer euthyreoten Kontrollgruppe (n = 48) verglichen. Die

  9. Das Doppelgesicht der Nichterwerbstätigkeit: Opportunitätsbilanz und Situationsdefinition als Determinanten der Zufriedenheit mit der Nichterwerbstätigkeit in einer Kohorte ehemaliger Gymnasiasten zwischen dem 30. und 43. Lebensjahr

    OpenAIRE

    Meulemann, Heiner; Hellwig, Jörg Otto

    2001-01-01

    'Dass unterschiedliche Definitionen dergleichen Situation zu unterschiedlichen Konsequenzen führen, wird an der Frage untersucht, ob die Tatsache und die Definition der Nichterwerbstätigkeit die Zufriedenheit mit ihr bei Kontrolle der Opportunität und des Geschlechts beeinflussen. Nach der Opportunitätsbilanzhypothese sollten Opportunitätsverluste die Zufriedenheit senken und Opportunitätsgewinne steigern; nach der Situationsdefinitionshypothese sollten positive Definitionen die Zufriedenheit...

  10. Hans Werner Richter - Wolfgang Borchert : zwei Schriftsteller im 2. Weltkrieg ; ihre Kriegseinsätze und die Umsetzung in Literatur

    OpenAIRE

    Brandes, Katrein

    2018-01-01

    Hans Werner Richter und Wolfgang Borchert, zwei der bekanntesten deutschen Nachkriegsschriftsteller, waren selbst auf erbittert umkämpften Schauplätzen des 2. Weltkrieges eingesetzt: Richter in Italien bei Cassino, Borchert an der Ostfront südlich Moskaus. Trotz der Auseinandersetzung mit ihren literarischen Zeugnissen aus dieser Zeit, wie Richters Roman „Die Geschlagenen“ und Borcherts Kurzgeschichten, ist die Frage nach ihrem eigenen Kriegserleben, nach Schuldbewusstsein und dem Niederschla...

  11. Die Suche nach den Gottesteilchen

    CERN Multimedia

    2007-01-01

    2008 wird der größte jemals gebaute Teilchenbeschleuniger in Betrieb genommen Anlässlich des Mathematik-Jahres 2008 hat der Experimentalphysiker der Universität Hamburg und der designierte Generaldirektor des europäischen Zentrums für Teilchenphysik CERN in Genf, Rolf-Dieter Heuer, die Bedeutung des Dialogs zwischen Naturwissenschaftlern und Philosophen hervorgehoben.

  12. Lassen Veränderungen des Prostata-spezifischen Antigen- (PSA- Spiegels nach Prostatastanzbiopsie Rückschlüsse auf das pathologische Ergebnis zu?

    Directory of Open Access Journals (Sweden)

    Volkmer BG

    2004-01-01

    Full Text Available Einleitung: Die diagnostische Biopsie der Prostata führt bekanntermaßen zum Anstieg des Serum-PSA-Spiegels. Diese prospektive Untersuchung sollte die Frage klären, ob die Änderungen des Serum-PSA-Spiegels nach Stanzbiopsie Rückschlüsse auf das histologische Ergebnis zulassen und so als Entscheidungshilfe bei der Frage der Rebiopsie dienen können. Patienten und Methoden: Insgesamt 79 konsekutive Patienten mit klinischem Verdacht auf das Vorliegen eines Prostatakarzinoms (PCA und einem Gesamt-PSA 50 ng/ml wurden in die Studie eingeschlossen. Ausschlußkriterien waren klinische Hinweise für eine Prostatitis und Prostatabiopsie innerhalb der letzten 3 Monate. Die Serum-PSA-Werte wurden mit einem ultrasensitiven Enzymimmunoassay bestimmt. Die Bestimmung des Gesamt-PSA und des freien PSA im Serum erfolgte unmittelbar vor und 60 Minuten nach der Biopsie. Die Spiegel des Gesamt-PSA und freien PSA, sowie die f/t-PSA-Ratio vor und nach Biopsie wurden in Korrelation zum histologischen Ergebnis gesetzt. Ergebnisse: 86 Biopsieserien wurden bei 79 Patienten durchgeführt. 38 Biopsieserien diagnostizierten ein PCA, 48 eine benigne Prostatahyperplasie (BPH. Die abschließende Histologie nach wiederholter Biopsie war PCA und BPH in je 43 Fällen. Insgesamt fand sich ein Anstieg des durchschnittlichen Gesamt-PSA von 18,39 ng/ml auf 107,8 ng/ml, des durchschnittlichen freien PSA von 3,43 ng/ml auf 33,7 ng/ml und der durchschnittlichen f/t PSA-Ratio von 18,1 % auf 52,0 %. Es fand sich keine Korrelation zwischen dem Anstieg dieser Parameter und der Anzahl der Biopsiezylinder (4–51. Bezüglich des histologischen Befundes ergaben sich statistisch signifikante Unterschiede für das Gesamt-PSA vor und die f/t PSA-Ratio vor und nach Stanzbiopsie. Schlußfolgerung: Die Analyse der PSA-Parameter nach Stanzbiopsie bietet keine zusätzliche Information über die konventionellen PSA-Parameter vor der Biopsie hinaus. Sie korrelieren vor allem nicht mit falsch

  13. Der Sport und die traditionelle Bewegungskultur der Aborigines

    OpenAIRE

    Wrogemann, Ohle

    2001-01-01

    Bei mehreren Studienaufenthalten in Australien wurde nach den Betrachtungsweisen der deutschen Sportwissenschaft umfangreiches Material der nachstehenden Quellen gesammelt: persönliche Kontakte zu einzelnen Personen, Besuch von öffentlichen und privaten Institutionen, Verfolgen des aktuellen Mediengeschehens, narrative Interviews mit Aborigines, Gespräche mit Experten unterschiedlicher Fachrichtungen, Politikern und Personen der multikulturellen australischen Gesellschaft, Teilnahme ...

  14. Besitzt Mentoring kultur- und strukturverändernde Potenziale?

    Directory of Open Access Journals (Sweden)

    Astrid Franzke

    2006-11-01

    Full Text Available Während Mentoring bislang hinsichtlich seiner individuellen Effekte vor allem in theoretischen Arbeiten untersucht und in Evaluationsstudien empirisch ausgewertet worden ist, fragen die Herausgeberinnen nach den kultur- und strukturverändernden Potenzialen durch Mentoring im universitären Feld.

  15. Immer schlanker und kranker? Models in der Werbung

    NARCIS (Netherlands)

    Koch, T.; Hofer, L.; Holtz-Bacha, C.

    2011-01-01

    Es gibt eine mit Regelmäßigkeit und Vehemenz in den Massenmedien geführte Diskussion darüber, ob die mediale Darstellung so genannter „Magermodels" insbesondere für junge Frauen als eine Art Vorbild dienen könnte und spezifische Wirkungen nach sich zöge, etwa negative Körperbilder, Magersucht oder

  16. Hinkelbeinchen und "little chicken's leg": deutsche und amerikanische Idiome als kommunikative Textsorten-Problematik

    Directory of Open Access Journals (Sweden)

    Martin Wierschin

    1998-12-01

    Full Text Available Als Marin Luther 1522 seine Übersetzung des Neuen Testaments nach der griechischen Edition des Erasmus von Rotterdam abschloß, hatte er dabei zwar mit größtem Sprachgefühl nicht nur dem deutschen, sondem auch dem idiomatischen 'logos' des Griechischen "auf das Maul" gesehen. Aber er mußte in seinem "Sendbrief vom Dolmetschen" 1530 dennoch zugeben, daß selbst er - zusammen mit seinen beiden Assistenten Melanchthon und Aurogallus - sehr oft zwei bis vier Wochen lang nach einem einzigen idiomatisch treffenden Wort zu suchen hatte. Damit wird von einem eminenten Kronzeugen, nämlich vom Schöpfer des protestantischen 'Hausbuches' Lutherbibel und vom eigentlichen Begründer einer einheitlichen deutschen Schrift­ sprache, samt ihrer sprach- und literargeschichtlich wirkungsmächtigen Idiomatik, die Schwierigkeit und Problematik idiomatischer Äquivalenzen und Transferenzen zwischen den Einzelsprachen verbürgt.

  17. Mapping pan-Arctic CH4 emissions using an adjoint method by integrating process-based wetland and lake biogeochemical models and atmospheric CH4 concentrations

    Science.gov (United States)

    Tan, Z.; Zhuang, Q.; Henze, D. K.; Frankenberg, C.; Dlugokencky, E. J.; Sweeney, C.; Turner, A. J.

    2015-12-01

    Understanding CH4 emissions from wetlands and lakes are critical for the estimation of Arctic carbon balance under fast warming climatic conditions. To date, our knowledge about these two CH4 sources is almost solely built on the upscaling of discontinuous measurements in limited areas to the whole region. Many studies indicated that, the controls of CH4 emissions from wetlands and lakes including soil moisture, lake morphology and substrate content and quality are notoriously heterogeneous, thus the accuracy of those simple estimates could be questionable. Here we apply a high spatial resolution atmospheric inverse model (nested-grid GEOS-Chem Adjoint) over the Arctic by integrating SCIAMACHY and NOAA/ESRL CH4 measurements to constrain the CH4 emissions estimated with process-based wetland and lake biogeochemical models. Our modeling experiments using different wetland CH4 emission schemes and satellite and surface measurements show that the total amount of CH4 emitted from the Arctic wetlands is well constrained, but the spatial distribution of CH4 emissions is sensitive to priors. For CH4 emissions from lakes, our high-resolution inversion shows that the models overestimate CH4 emissions in Alaskan costal lowlands and East Siberian lowlands. Our study also indicates that the precision and coverage of measurements need to be improved to achieve more accurate high-resolution estimates.

  18. Methanogenic Conversion of CO2 Into CH4

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, S.H., Ferry, J.G., Schoell, M.

    2012-05-06

    This SBIR project evaluated the potential to remediate geologic CO2 sequestration sites into useful methane gas fields by application of methanogenic bacteria. Such methanogens are present in a wide variety of natural environments, converting CO2 into CH4 under natural conditions. We conclude that the process is generally feasible to apply within many of the proposed CO2 storage reservoir settings. However, extensive further basic R&D still is needed to define the precise species, environments, nutrient growth accelerants, and economics of the methanogenic process. Consequently, the study team does not recommend Phase III commercial application of the technology at this early phase.

  19. ASS-induzierte Asthmaanfälle nach ASS-Desaktivierung - Fallbericht einer seltenen Komplikation

    OpenAIRE

    Doktorowski, S; Creutz, P; Förster-Ruhrmann, U; Olze, H

    2015-01-01

    Einleitung: Patienten mit einer nasalen Polyposis (NP), einem Asthma und einer ASS-Intoleranz sind häufig durch schwere Krankheitsverläufe gekennzeichnet. Die ASS-Desaktivierung ist eine Therapieoption mit günstigen Effekten auf rhinitische und pulmonale Beschwerden.Methoden: Vorstellung eines ungewöhnlichen Verlaufs eines Patienten nach ASS-Desaktivierung. Ergebnisse: Ein männlicher 34-jähriger Patient mit einer ASS-Trias (NP-Grad 2., FEV-1 94,7%, Ø Peakflow 470 l/Min) erhielt stationär p...

  20. Quantifying Gas Flaring CH4 Consumption Using VIIRS

    Directory of Open Access Journals (Sweden)

    Xiaodong Zhang

    2015-07-01

    Full Text Available A method was developed to estimate the consumption of CH4 and the release of CO2 by gas flaring using VIIRS nighttime data. The results agreed with the field data collected at six stations in Bakken field, North Dakota, USA, within ±50%, as measured by mean relative errors and with a correlation coefficient of 0.75. This improved over the NOAA NightFire estimates, likely due to: (1 more stringent data selection using only the middle portion of cloud-free VIIRS nighttime imagery; (2 the use of a lower heating rate, which is more suitable for the field condition; and (3 more accurate efficiency factors in calculating completeness in combustion and conversion of total reaction energy into radiant energy that can be sensed by a satellite sensor. While using atmospherically-corrected data can further improve the estimate of CH4 consumption by ~10%, the major uncertainty remains as being the form factor of the flares, particularly the ratio of total surface area of a flare to the cross-section area that was seen by a satellite sensor.

  1. Uncertainties in modelling CH4 emissions from northern wetlands in glacial climates: effect of hydrological model and CH4 model structure

    Directory of Open Access Journals (Sweden)

    J. van Huissteden

    2009-07-01

    Full Text Available Methane (CH4 fluxes from northern wetlands may have influenced atmospheric CH4 concentrations at climate warming phases during the last 800 000 years and during the present global warming. Including these CH4 fluxes in earth system models is essential to understand feedbacks between climate and atmospheric composition. Attempts to model CH4 fluxes from wetlands have previously been undertaken using various approaches. Here, we test a process-based wetland CH4 flux model (PEATLAND-VU which includes details of soil-atmosphere CH4 transport. The model has been used to simulate CH4 emissions from continental Europe in previous glacial climates and the current climate. This paper presents results regarding the sensitivity of modeling glacial terrestrial CH4 fluxes to (a basic tuning parameters of the model, (b different approaches in modeling of the water table, and (c model structure. In order to test the model structure, PEATLAND-VU was compared to a simpler modeling approach based on wetland primary production estimated from a vegetation model (BIOME 3.5. The tuning parameters are the CH4 production rate from labile organic carbon and its temperature sensitivity. The modelled fluxes prove comparatively insensitive to hydrology representation, while sensitive to microbial parameters and model structure. Glacial climate emissions are also highly sensitive to assumptions about the extent of ice cover and exposed seafloor. Wetland expansion over low relief exposed seafloor areas have compensated for a decrease of wetland area due to continental ice cover.

  2. Effect of interannual variation in winter vertical mixing on CH4 dynamics in a subtropical reservoir

    Science.gov (United States)

    Itoh, Masayuki; Kobayashi, Yuki; Chen, Tzong-Yueh; Tokida, Takeshi; Fukui, Manabu; Kojima, Hisaya; Miki, Takeshi; Tayasu, Ichiro; Shiah, Fuh-Kwo; Okuda, Noboru

    2015-07-01

    Although freshwaters are considered to be substantial natural sources of atmospheric methane (CH4), in situ processes of CH4 production and consumption in freshwater ecosystems are poorly understood, especially in subtropical areas, leading to uncertainties in the estimation of global CH4 emissions. To improve our understanding of physical and biogeochemical factors affecting CH4 dynamics in subtropical lakes, we examined vertical and seasonal profiles of dissolved CH4 and its carbon isotope ratio (δ13C) and conducted incubation experiments to assess CH4 production and oxidation in the deep subtropical Fei-Tsui Reservoir (FTR; Taiwan). The mixing pattern of the FTR is essentially monomixis, but the intensity of winter vertical mixing changes with climatic conditions. In years with incomplete vertical mixing (does not reach the bottom) and subsequent strong thermal stratification resulting in profundal hypoxia, we observed increases in sedimentary CH4 production and thus profundal CH4 storage with the development of reducing conditions. In contrast, in years with strong winter vertical mixing to the bottom of the reservoir, CH4 production was suppressed under NO3--rich conditions, during which denitrifiers have the competitive advantage over methanogens. Diffusive emission from profundal CH4 storage appeared to be negligible due to the efficiency of CH4 oxidation during ascent through methane-oxidizing bacteria (MOB) activity. Most of the profundal CH4 was rapidly oxidized by MOB in both oxic and anoxic layers, as characterized by its carbon isotope signature. In contrast, aerobic CH4 production in the subsurface layer, which may be enhanced under high temperatures in summer, may account for a large portion of atmospheric CH4 emissions from this reservoir. Our CH4 profiling results provide valuable information for future studies predicting CH4 emissions from subtropical lakes with the progress of global warming.

  3. High rate monitoring CH4 production dynamics and their link with behavioral phases in cattle

    OpenAIRE

    Blaise, Yannick; Lebeau, Frédéric; Andriamandroso, Andriamasinoro; Beckers, Yves; Heinesch, Bernard; Bindelle, Jérôme

    2016-01-01

    Microbial fermentation in the rumen produces methane (CH4) which is a loss of energy for ruminants and also contributes to global warming. While the respiration chamber is the standard reference for CH4 emissions quantification, daily CH4 production dynamics can be measured only by steps of 30 min and measurements on pasture are impossible. The alternative method using SF6 as tracer gas can be applied for grazing animals but provides average CH4 production values over at least several hours, ...

  4. Lebenspartnerschaften mit und ohne Kinder: Ambivalenzen der Institutionalisierung privater Lebensformen

    OpenAIRE

    Lüscher, Kurt; Grabmann, Barbara

    2002-01-01

    Die historisch neue Aufgabe der rechtlichen Regelung von Lebensgemeinschaften gleichgeschlechtlich orientierter Menschen beinhaltet den Abbau von Diskriminierungen und stellt Fragen nach dem Verständnis von Ehe und Familie sowie deren Verhältnis zu anderen privaten Lebensformen. Die Analyse der zahlenmäßigen Verbreitung gleichgeschlechtlicher Partnerschaften und der Begründung ihrer Verrechtlichung verweist auf spezifische Ambivalenzen der Institutionalisierung privater Lebensformen. Ein Über...

  5. Ontologische und epistemologische Grundlagen qualitative Forschung

    OpenAIRE

    Vasilachis de Gialdino, Irene

    2009-01-01

    Dieser Beitrag zielt auf das Herzstück qualitativer Forschung, indem gezeigt wird, dass es – aus der Perspektive einer Epistemologie des "gewussten" Subjekts – erforderlich ist, zunächst deren ontologische und dann deren epistemologische Grundlagen neu zu überdenken. Hierzu zeichne ich in einem ersten Schritt den Weg von einer Epistemologie des "bewussten" Subjekts hin zu einer Epistemologie des "gewussten" Subjekts nach, die ich als neuen (und nicht exklusiven) Weg des Wissens vorschlage. Da...

  6. Entscheidungsprozesse und Partizipation in der Stadtentwicklung Dresdens

    OpenAIRE

    Schmidt-Lerm, Susanne

    2010-01-01

    Untersucht wurde die Auseinandersetzung um das Autobahnbauvorhaben A 17 Dresden - Prag zwischen 1990 und 1995 als ein Beispiel der Stadtentwicklung Dresdens. Seit 1935 als Reichsautobahn ins Sudetenland geplant, sollte dieses Verkehrsprojekt nach 1990 als „Lückenschluß im europäischen Autobahnnetz“ umgesetzt werden. Angesichts des hohen Konfliktpotentials erlangte der Fall überregionale Aufmerksamkeit und Beispielcharakter für die neuen Bundesländer. Die Kontroverse gipfelte im ersten Bürgere...

  7. Windrow composting mitigated CH4 emissions: characterization of methanogenic and methanotrophic communities in manure management.

    Science.gov (United States)

    Chen, Ruirui; Wang, Yiming; Wei, Shiping; Wang, Wei; Lin, Xiangui

    2014-12-01

    With increasing livestock breeding, methane (CH4 ) emissions from manure management will increasingly contribute more to atmospheric CH4 concentration. The dynamics of methanogens and methanotrophs have not yet been studied in the manure environment. The current study combines surface CH4 emissions with methanogenic and methanotrophic community analyses from two management practices, windrow composting (WCOM) and solid storage (SSTO). Our results showed that there was an c. 50% reduction of CH4 emissions with WCOM compared with SSTO over a 50-day period. A sharp decrease in the quantities of both methanogens and methanotrophs in WCOM suggested that CH4 mitigation was mainly due to decreased CH4 production rather than increased CH4 oxidation. Pyrosequencing analysis demonstrated that aeration caused a clear shift of dominant methanogens in the manure, with specifically a significant decrease in Methanosarcina and increase in Methanobrevibacter. The composition of methanogenic community was influenced by manure management and regulated CH4 production. A sharp increase in the quantity of methanotrophs in SSTO suggested that microbial CH4 oxidation is an important sink for the CH4 produced. The increased abundance of Methylococcaceae in SSTO suggested that Type I methanotrophs have an advantage in CH4 oxidation in occupying niches under low CH4 and high O2 conditions. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  8. "Ich soll nicht zu mir selbst kommen" : Werther, Goethe und die Formung des Subjekts in der Moderne

    OpenAIRE

    Petersdorff, Dirk von (Prof. Dr.)

    2012-01-01

    Die Leiden des jungen Werther: Sie gehen aus einem neuen Reflexions- uns Ausgleichungsbedürfnis hervor, aus der Suche nach einem konsistenten Ich. Werther erlebt die kognitiven und affektiven Veränderungen, die die Moderne heraufführt, und aus diesen Erfahrungen geht sein Verlangen nach Einheit hervor (...). Die Suche nach dem einheitlichen, festen, verläßlichen Ich hält den Briefroman zusammen, und die Gattungswahl korrespondiert mit der Fragestellung, denn das Medium des Briefes hat im 18. ...

  9. Imaging of postarthroscopic complications after knee injuries; Bildgebung postarthroskopischer Komplikationen nach Knieverletzungen

    Energy Technology Data Exchange (ETDEWEB)

    Schueller-Weidekamm, C. [Medizinische Universitaet Wien, Abteilung fuer Neuroradiologie und muskuloskelettale Radiologie, Klinik fuer Radiodiagnostik, Wien (Austria); Skrbensky, G. von [Medizinische Universitaet Wien, Klinik fuer Orthopaedie, Wien (Austria)

    2012-11-15

    The most common joint injuries in professional and recreational sports participants and also in the total population are knee injuries. Arthroscopy is indicated if this modality will improve the patient outcome and potential long-term complications can be avoided. Although uncommon, complications following arthroscopy are mostly evaluated by magnetic resonance imaging (MRI). For planning further therapy strategies following postarthroscopic complications, e.g. if anterior cruciate ligament (ACL) reconstruction is required, digital radiographs and computed tomography (CT) are helpful. This article provides an overview of the different procedures for surgical treatment which are a prerequisite for the analysis of postarthroscopic images. In addition typical complications after treatment of meniscal and chondral injuries as well as after ACL reconstruction are described and typical signs in MRI, radiography and CT are explained in detail. (orig.) [German] Kniegelenkverletzungen sind nicht nur bei Profisportlern, sondern auch in der Gesamtbevoelkerung die haeufigsten Gelenkverletzungen. Die Indikation zur arthroskopischen Operation wird gestellt, wenn im Vergleich zur konservativen Therapie ein besseres Ergebnis postarthroskopisch zu erwarten ist und potenzielle Spaetkomplikationen verhindert werden koennten. Die selten aber dennoch auftretenden postarthroskopischen Komplikationen werden zumeist mit der Magnetresonanztomographie (MRT) abgeklaert. Zur weiteren Therapieplanung nach Komplikationen, z. B. wenn eine Kreuzbandrevision notwendig ist, sind die digitale Projektionsradiographie und die Computertomographie (CT) hilfreich. Dieser Artikel bietet eine kurze Uebersicht ueber die unterschiedlichen Operationstechniken, die eine Voraussetzung fuer das Verstaendnis der bildgebenden postoperativen Veraenderungen sind. Weiter wird auf die haeufigsten Komplikationen nach Meniskus- und Knorpeloperationen sowie nach vorderer Kreuzbandrekonstruktion und den damit

  10. Die Rolle von Charaktereigenschaften, Umwelt und dem Genpolymorphismus des Serotonintransporters bei der Entstehung on Major Depression

    OpenAIRE

    Schmid, Bianca

    2011-01-01

    1.1 Hintergrund und Ziele Weltweit sind derzeit 121 Millionen Menschen von Depressionen betroffen. Unter diesem Krankheitsbild versteht man einen Verlust von Interesse oder Freude, depressive Verstimmung, Müdigkeit und Energieverlust, verminderte Denk- und Entscheidungsfähigkeit, Unruhe oder Verlangsamung, aber auch körperliche Symptome wie Schlafstörungen oder Appetitverlust gehören dazu. Je nach Schwere und Ausprägungsgrad der Erkrankung sind die Betroffenen in ihrem Lebensalltag enorm beei...

  11. Ein Lehr- und Studienbuch der interkulturellen Pädagogik A Textbook of Inter-Cultural Pedagogy

    OpenAIRE

    Kerstin Schenkel

    2003-01-01

    Renate Nestvogel gibt anhand von Auszügen ausgewählter biographischer Romane und Erzählungen einen Einblick in Aspekte weibliche verschiedener Kulturen und Gesellschaften. Den Texten vorangestellt ist u. a. ein Forschungsüberblick zu Sozialisationskonzepten, zur weiblichen Sozialisation und den Geschlechterverhältnissen sowie zur Kindheit und Jugend. Die Texte werden thematisch nach unterschiedlichen Themen wie Lebensräumen, Kinderarbeit, Phantasie, Geschlechtersozialisation, Körpersozialisat...

  12. Replacement of CH4 in the hydrate by use of liquid CO2

    International Nuclear Information System (INIS)

    Ota, Masaki; Morohashi, Kenji; Abe, Yuki; Watanabe, Masaru; Smith, Richard Lee Jr.; Inomata, Hiroshi

    2005-01-01

    The dynamics of CH 4 replacement in the CH 4 hydrate with saturated liquid CO 2 at 273.2 K was measured with a high pressure optical cell. The results showed that CH 4 in the hydrate gradually moved to the liquid CO 2 phase while CO 2 in the liquid phase penetrated into the hydrate from the quantitative analysis. The decomposing process of the CH 4 hydrate during the replacement was analyzed with in situ Raman spectroscopy, which allowed us to distinguish the cage structure of the CH 4 hydrate and discuss the microscopic view of the replacement in the hydrate. It was found that the decomposition of the medium cage (M-cage) in the CH 4 hydrate proceeded faster than that of the small cage (S-cage). The observed rate difference could be related to the stability of the S-cage in the CH 4 hydrate or the re-formation tendency of CH 4 and water molecules in the S-cage after decomposing the hydrate structure, whereas the guest molecule exchange of CH 4 with CO 2 could occur in the M-cage. Based on the experimental data, we developed a kinetic model for calculation of the CH 4 remaining in the hydrate considering the decomposition rate difference between the M-cage and S-cage in the CH 4 hydrate. The results indicate that the driving force could be the fugacity difference between the fluid phase and the hydrate phase for the replacement process

  13. Zoophilie in Zoologie und Roman: Sex und Liebe zwischen Mensch und Tier bei Plutarch, Plinius dem Älteren, Aelian und Apuleius

    Directory of Open Access Journals (Sweden)

    Judith Hindermann

    2011-09-01

    Full Text Available Die Bedeutung von Zoophilie in der antiken Literatur wurde bislang – mit Ausnahme des Mythos – kaum untersucht. Überblickt man die überlieferten literarischen Texte, fällt auf, dass Zoophilie ausserhalb des Mythos vor allem in zwei literarischen Gattungen auftritt : Einerseits in den zoologischen Schriften von Plutarch, Plinius dem Älteren und Aelian, andererseits im antiken Roman, d.h. in den Metamorphosen des Apuleius und im pseudo-lukianischen Onos. In diesem Beitrag soll untersucht werden, welche Funktion Zoophilie in den beiden literarischen Gattungen hat und wie die Autoren die sexuelle Praktik bewerten, die weder nach griechischem noch römischen Recht strafbar war. Da Vorstellungen über Tiere eng mit Gender und Geschlechterhierarchien verbunden sind, soll insbesondere die Frage berücksichtigt werden, inwiefern männliche und weibliche Verhaltens- und Rollenzuschreibungen bei der Darstellung zoophiler Akte wirksam werden.

  14. Scintigraphic diagnosis of silent aspiration following double-sided lung transplantation; Szintigraphischer Nachweis einer stillen Aspiration nach beidseitiger Lungentransplantation

    Energy Technology Data Exchange (ETDEWEB)

    Toenshoff, G. [Kiel Univ. (Germany). Klinik fuer Nuklearmedizin; Stock, U. [Kiel Univ. (Germany). Klinik fuer Herz- und Gefaesschirurgie; Bohuslavizki, K.H. [Kiel Univ. (Germany). Klinik fuer Nuklearmedizin; Brenner, W. [Kiel Univ. (Germany). Klinik fuer Nuklearmedizin; Costard-Jaeckle, A. [Kiel Univ. (Germany). Klinik fuer Herz- und Gefaesschirurgie; Cremer, J. [Kiel Univ. (Germany). Klinik fuer Herz- und Gefaesschirurgie; Clausen, M. [Kiel Univ. (Germany). Klinik fuer Nuklearmedizin

    1996-08-01

    We present a case of a 25 year old patient who underwent double-sided lung transplantation and suffered from recurrent pneumonia. Silent aspiration was suspected clinically. Aspiration was proved by scintigraphy enabling to discriminate between direct oro-pulmonal aspiration and aspiration after gastro-esophageal reflux. (orig.) [Deutsch] Vorgestellt wird der Fall einer 25jaehrigen Patientin nach beidseitiger Lungentransplantation und rezidivierenden Pneumonien. Klinisch bestand der Verdacht auf eine stille Aspiration. Szintigraphisch gelang sowohl der Aspirationsnachweis als auch eine Differenzierung hinsichtlich der Genese: Direkte oro-pulmonale Aspiration versus Aspiration nach gastrooesophagealem Reflux. (orig.)

  15. Contribution of Anthropogenic and Natural Emissions to Global CH4 Balances by Utilizing δ13C-CH4 Observations in CarbonTracker Data Assimilation System (CTDAS)

    Science.gov (United States)

    Kangasaho, V. E.; Tsuruta, A.; Aalto, T.; Backman, L. B.; Houweling, S.; Krol, M. C.; Peters, W.; van der Laan-Luijkx, I. T.; Lienert, S.; Joos, F.; Dlugokencky, E. J.; Michael, S.; White, J. W. C.

    2017-12-01

    The atmospheric burden of CH4 has more than doubled since preindustrial time. Evaluating the contribution from anthropogenic and natural emissions to the global methane budget is of great importance to better understand the significance of different sources at the global scale, and their contribution to changes in growth rate of atmospheric CH4 before and after 2006. In addition, observations of δ13C-CH4 suggest an increase in natural sources after 2006, which matches the observed increase and variation of CH4 abudance. Methane emission sources can be identified using δ13C-CH4, because different sources produce methane with process-specific isotopic signatures. This study focuses on inversion model based estimates of global anthropogenic and natural methane emission rates to evaluate the existing methane emission estimates with a new δ13C-CH4 inversion system. In situ measurements of atmospheric methane and δ13C-CH4 isotopic signature, provided by the NOAA Global Monitoring Division and the Institute of Arctic and Alpine Research, will be assimilated into the CTDAS-13C-CH4. The system uses the TM5 atmospheric transport model as an observation operator, constrained by ECMWF ERA Interim meteorological fields, and off-line TM5 chemistry fields to account for the atmospheric methane sink. LPX-Bern DYPTOP ecosystem model is used for prior natural methane emissions from wetlands, peatlands and mineral soils, GFED v4 for prior fire emissions and EDGAR v4.2 FT2010 inventory for prior anthropogenic emissions. The EDGAR antropogenic emissions are re-divided into enteric fermentation and manure management, landfills and waste water, rice, coal, oil and gas, and residential emissions, and the trend of total emissions is scaled to match optimized anthropogenic emissions from CTE-CH4. In addition to these categories, emissions from termites and oceans are included. Process specific δ13C-CH4 isotopic signatures are assigned to each emission source to estimate 13CH4 fraction

  16. Global Inverse Modeling of CH4 and δ13C-CH4 Measurements to Understand Recent Trends in Methane Emissions

    Science.gov (United States)

    Karmakar, S.; Butenhoff, C. L.; Rice, A. L.; Khalil, A. K.

    2017-12-01

    Methane (CH4) is the second most important greenhouse gas with a radiative forcing of 0.97 W/m2 including both direct and indirect effects and a global warming potential of 28 over a 100-year time horizon. After a decades-long period of decline beginning in the 1980s, the methane growth rate rebounded in 2007 for reasons that are of current debate. During this same growth period atmospheric methane became less enriched in the 13CH4 isotope suggesting the recent CH4 growth was caused by an increase in 13CH4-depleted biogenic emissions. Recent papers have attributed this growth to increasing emissions from wetlands, rice agriculture, and ruminants. In this work we provide additional insight into the recent behavior of atmospheric methane and global wetland emissions by performing a three-dimensional Bayesian inversion of surface CH4 and 13CH4/12CH4 ratios using NOAA Global Monitoring Division (GMD) "event-level" CH4 measurements and the GEOS-Chem chemical-transport model (CTM) at a horizontal grid resolution of 2ox2.5o. The spatial pattern of wetland emissions was prescribed using soil moisture and temperature from GEOS-5 meteorology fields and soil carbon pools from the Lund-Potsdam-Jena global vegetation model. In order to reduce the aggregation error caused by a potentially flawed distribution and to account for isotopic measurements that indicate northern high latitude wetlands are isotopically depleted in 13CH4 relative to tropical wetlands we separated our pattern into three latitudinal bands (90-30°N, 30°N-0, 0-90°S). Our preliminary results support previous claims that the recent increase in atmospheric methane is driven by increases in biogenic CH4 emissions. We find that while wetland emissions from northern high latitudes (90-30°N) remained relatively constant during this time, southern hemisphere wetland emissions rebounded from a decade-long decline and began to rise again in 2007 and have remained elevated to the present. Emissions from rice

  17. Indirect MR-arthography in the fellow up of autologous osteochondral transplantation; Indirekte MR-Arthrographie zur Verlaufskontrolle nach autologer osteochondraler Transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Herber, S.; Pitton, M.B.; Kalden, P.; Thelen, M.; Kreitner, K.F. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Runkel, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Unfallchirurgie

    2003-02-01

    following autologous osteochondral transplantation. Assessment of transplant vitality, osseous fixation and stability is possible. (orig.) [German] Zielsetzung: Evaluation der Befunde nach indirekter MR-Arthrographie bei Patienten mit autologer osteochondraler Transplantation. Patienten und Methoden: 10 konsekutive Patienten mit einer Mosaik-Plastik wurden drei, 6 und 12 Monate nach dem Eingriff mittels indirekter MR-Arthrographie untersucht. Das MR-Protokoll bei 1,5T beinhaltete neben nativen PD- und T{sub 2}-gewichteten TSE-Sequenzen mit und ohne Fett-Suppression T{sub 1}-gewichtete, fettsupprimierte SE-Sequenzen vor und unmittelbar nach Kontrastmittelgabe sowie nach Bewegung des Gelenkes. Die Bildanalyse wurde gemeinsam von zwei Radiologen durchgefuehrt und beinhaltete die Auswertung der Signalintensitaet (SI) und Integritaet des knoechernen Zylinders ebenso wie der Knorpeloberflaeche, das Vorhandensein eines Knochenmarkoedems und eines Gelenkergusses. Ergebnisse: Drei Monate nach dem Eingriff zeigte sich in allen Faellen in der T{sub 2}-TSE-Sequenz ein ausgepraegtes Knochenmarkoedem auf Empfaenger- und Donorseite, korrespondierend zu einem deutlichem Signalintensitaetsanstieg nach Kontrastmittelgabe. Die Grenzzone zwischen dem Transplantat und dem originaerem Knochen zeigte eine erhoehte SI nach drei und 6 Monaten in der T{sub 2}-TSE-Sequenz sowie nach i.v. Gd-DTPA-Gabe. Eine Transplantatdislokation wurde in keinem Fall beobachtet. Als Zeichen der Vitalitaet des osteochondralen Transplantats normalisierte sich das Marksignal in der T{sub 1}-SE-Sequenz in den meisten Faellen nach 6 bzw. 12 Monaten. Die indirekte MR-Arthrographie war dem Nativ-Scan ueberlegen bei der Beurteilung der knorpeligen Ueberdeckung des Transplantats. In allen Faellen zeigte sich eine komplette Ueberdeckung des knoechernen Zylinders mit Gelenkknorpel. Transplantierter und originaerer hyaliner Knorpel zeigten einen deutlichen Anstieg der SI in der indirekten MR-Arthrographie. Signalalterationen und

  18. Landscape Controls of CH4 Fluxes in a Catchment of the Forest Tundra in Northern Siberia

    Science.gov (United States)

    Flessa, H.; Rodionov, A.; Guggenberger, G.; Fuchs, H.; Magdon, P.; Shibistova, O.; Zrazhevskaya, G.; Kasansky, O.; Blodau, C.

    2007-12-01

    Soils have the capacity to both produce and consume atmospheric methane. The direction and the size of net- CH4 exchange between soils and atmosphere is mainly controlled by the soil aeration, temperature and the amount of bioavailable organic matter. All these factors are strongly influenced by distribution and seasonal dynamics of permafrost. Thus, distribution of permafrost and the thickness of the active layer can exert strong influence on CH4 dynamics in artic and northern boreal ecosystems. We analyzed the spatial and temporal variability of net-CH4 exchange within a catchment located in the Siberian forest tundra at the eastern shore of the lower Yenissej River to constrain the current function of this region as a sink or source of atmospheric CH4 and to gain insight into the potential for climatic change to alter the rate and form of carbon cycling and CH4 fluxes in this region. Net-fluxes of CH4 were measured from July to November 2003 and from August 2006 to July 2007 on representative soils of the catchment (mineral soils with different thawing depth, soils of bog plateaux) and on a thermokarst pond. In addition, dissolved CH4 in the stream draining the catchment was determined. Field observations, classification of landscape structures from satellite images and flux measurements were combined to estimate total catchment CH4 exchange. Nearly all soils of the catchment were net-sinks of atmospheric CH4 with annual CH4-C uptake rates ranging between 1.2 and 0.2 kg ha-1 yr-1. The active layer depth was the main factor determining the size of CH4 uptake. Total net-exchange of CH4 from the catchment was dominated by ponds that covered only about 2% of the catchment area. Due to high CH4 emission from these aquatic systems, the catchment was a net source of atmospheric CH4 with a mean annual emission of approximately 170 kg CH4-C ha-1. CH4 concentration in streams draining the catchment can help to identify areas with high CH4 production. The results suggest

  19. Effects of plant species on soil microbial processes and CH4 emission from constructed wetlands

    International Nuclear Information System (INIS)

    Wang, Yanhua; Yang, Hao; Ye, Chun; Chen, Xia; Xie, Biao; Huang, Changchun; Zhang, Jixiang; Xu, Meina

    2013-01-01

    Methane (CH 4 ) emission from constructed wetland has raised environmental concern. This study evaluated the influence of mono and polyculture constructed wetland and seasonal variation on CH 4 fluxes. Methane emission data showed large temporal variation ranging from 0 to 249.29 mg CH 4 m −2 h −1 . Results indicated that the highest CH 4 flux was obtained in the polyculture system, planted with Phragmites australis, Zizania latifolia and Typha latifolia, reflecting polyculture system could stimulate CH 4 emission. FISH analysis showed the higher amount of methanotrophs in the profile of Z. latifolia in both mono and polyculture systems. The highest methanogens amount and relatively lower methanotrophs amount in the profile of polyculture system were obtained. The results support the characteristics of CH 4 fluxes. The polyculture constructed wetland has the higher potential of global warming. -- Highlights: ► The polyculture constructed wetland has the higher contribution to CH 4 emission. ► The CH 4 –C conversion ranged from 0 to 3.7%. ► The Z. latifolia played important roles in methanotrophs growth and CH 4 consumption. ► Major influence of T-N, TOC and plant cover on CH 4 emission was obtained. -- The polyculture constructed wetland has the higher contribution to global warming

  20. Neutron scattering and proton spin conversion in solid CH4

    International Nuclear Information System (INIS)

    Lushington, K.J.; Morrison, J.A.

    1977-01-01

    The total neutron cross section of pure and O 2 -doped condensed CH 4 has been measured in the temperature range 0.75< T<100 K. The neutron wave length was sufficiently long (4.7 A) so that changes in cross section could be directly related to changes in γI(I + 1)μ, the mean squared proton nuclear angular momentum per molecule, to a sensitivity of about 1%. The temperature dependences of γI(I + 1)μ for the pure and doped specimens differ considerably in solid phase II(T<20.4 K). For the former specimen, the change in cross section is consistent with conversion occurring between the nuclear spin symmetry species on the orientationally disordered sublattices only. The addition of oxygen enhances the rate of conversion such that the value of γI(I + 1)μ corresponds to conversion on both the disordered and ordered sublattices. The characteristic lifetimes of the catalyzed and uncatalyzed conversion processes have been estimated. (author)

  1. Der Mensch und die "Künstliche Intelligenz" : Eine Profilierung und kritische Bewertung der unterschiedlichen Grundauffassungen vom Standpunkt des gemäßigten Realismus

    OpenAIRE

    Eraßme, Rolf

    2002-01-01

    Nach einer kurzen Einleitung in die Problematik der "Künstlichen Intelligenz" (KI) nimmt die Arbeit ihren Ausgang in einer zusammenfassenden Darstellung des Standes der Technik. Daran anschließend werden vier verschiedene naturwissenschaftliche Grundauffassungen vom Menschen und der KI profiliert: Symbolismus, Konnektionismus, Biologismus und Physikalismus. Der Schwerpunkt liegt auf der Verdeutlichung der anthropologisch relevanten Aussagen zu Intelligenz, Geist, Denken, Erkennen, Wille, Bewu...

  2. Morphologische Qualitätsmerkmale der Mäuseeizelle und deren Zusammenhang mit einer Fehlverteilung des Chromosoms 16

    OpenAIRE

    Rogge, Sabine

    2009-01-01

    Eizellen der Maus wurden nach lichtmikroskopischen Kriterien bewertet. Mittels Fluoreszenz- in- situ- Hybridisierung wurden zudem meiotische Fehlverteilungen des Chromosom 16 der Maus 16 dargestellt. Die Korrelation zwischen morphologischen Kriterien und chromosomaler Fehlverteilung wurde untersucht.

  3. Observing and modeling links between soil moisture, microbes and CH4 fluxes from forest soils

    Science.gov (United States)

    Christiansen, Jesper; Levy-Booth, David; Barker, Jason; Prescott, Cindy; Grayston, Sue

    2017-04-01

    Soil moisture is a key driver of methane (CH4) fluxes in forest soils, both of the net uptake of atmospheric CH4 and emission from the soil. Climate and land use change will alter spatial patterns of soil moisture as well as temporal variability impacting the net CH4 exchange. The impact on the resultant net CH4 exchange however is linked to the underlying spatial and temporal distribution of the soil microbial communities involved in CH4 cycling as well as the response of the soil microbial community to environmental changes. Significant progress has been made to target specific CH4 consuming and producing soil organisms, which is invaluable in order to understand the microbial regulation of the CH4 cycle in forest soils. However, it is not clear as to which extent soil moisture shapes the structure, function and abundance of CH4 specific microorganisms and how this is linked to observed net CH4 exchange under contrasting soil moisture regimes. Here we report on the results from a research project aiming to understand how the CH4 net exchange is shaped by the interactive effects soil moisture and the spatial distribution CH4 consuming (methanotrophs) and producing (methanogens). We studied the growing season variations of in situ CH4 fluxes, microbial gene abundances of methanotrophs and methanogens, soil hydrology, and nutrient availability in three typical forest types across a soil moisture gradient in a temperate rainforest on the Canadian Pacific coast. Furthermore, we conducted laboratory experiments to determine whether the net CH4 exchange from hydrologically contrasting forest soils responded differently to changes in soil moisture. Lastly, we modelled the microbial mediation of net CH4 exchange along the soil moisture gradient using structural equation modeling. Our study shows that it is possible to link spatial patterns of in situ net exchange of CH4 to microbial abundance of CH4 consuming and producing organisms. We also show that the microbial

  4. From California dreaming to California data: Challenging historic models for landfill CH4 emissions

    OpenAIRE

    Spokas, Kurt; Bogner, Jean; Corcoran, Meg; Walker, Scott

    2015-01-01

    Abstract Improved quantification of diverse CH4 sources at the urban scale is needed to guide local GHG mitigation strategies in the Anthropocene. Herein, we focus on landfill CH4 emissions in California, challenging the current IPCC methodology which focuses on a climate dependency for landfill CH4 generation (methanogenesis), but does not explicitly consider climate or soil dependencies for emissions. Relying on a comprehensive California landfill database, a field-validated process-based m...

  5. Methane (CH4) Flux for North America L4 Daily V1 (CMS_CH4_FLX_NAD) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The CMS Methane (CH4) Flux for North America data set contains estimates of methane emission in North America based on an inversion of the GEOS-Chem chemical...

  6. Oberbergamt fuer das Saarland und das Land Rheinland-Pfalz, Bergamt Saarbruecken/Bergamt Rheinland-Pfalz. Annual report 1999. Economic and technical aspects, industrial safety and environmental protection, statistics, activities of the mining authorities; Oberbergamt fuer das Saarland und das Land Rheinland-Pfalz, Bergamt Saarbruecken/Bergamt Rheinland-Pfalz. Jahresbericht 1999.. Bergwirtschaft, Bergtechnik, Arbeitsschutz, Umweltschutz, Statistiken, Taetigkeiten der Bergbehoerden

    Energy Technology Data Exchange (ETDEWEB)

    Boettcher, R.; Hugo, K.H.; Kuhn, M.; Strauch, T. (comps.)

    1999-07-01

    The developments in Saarland and Rhineland-Palatinate mining are presented. Structure and responsibilities of the regional mines inspectorate are described, and their activities in the following fields are reported: industrial safety, health, mining and safety, mining and environmental protection. (orig.) [German] Nach Darstellung der bergwirtschaftlichen Entwicklung im Saarland und im Land Rheinland-Pfalz wird ueber den Aufbau und die Zustaendigkeit der Bergbehoerden sowie ueber deren Taetigkeiten auf folgenden Gebieten berichtet: Arbeits- und Gesundheitsschutz, Bergtechnik und Sicherheit, Bergbau und Umwelt. (orig.)

  7. RELATIONSHIP BETWEEN ATMOSPHERIC CO_2 AND CH_4 CONCENTRATIONS AT SYOWA STATION, ANTARCTICA

    OpenAIRE

    アオキ, シュウジ; ナカザワ, タカキヨ; ムラヤマ, ショウヘイ; シミズ, アキラ; ハヤシ, マサヒコ; イワイ, クニモト; Shuhji, AOKI; Takakiyo, NAKAZAWA; Shohei, MURAYAMA; Akira, SHIMIZU; Masahiko, HAYASHI; Kunimoto, IWAI

    1994-01-01

    Precise measurements of the atmospheric CO_2 and CH_4 concentrations have been continued at Syowa Station since 1984 and 1987,respectively. Measured concentrations show secular increase, together with seasonal cycle and irregular variations. Negative correlation is clearly seen between the secular trends of the CO_2 and CH_4 concentrations. The increase rates of CO_2 and CH_4 show oscillations with periods of 2.3 to 2.8 years. The phases of the average seasonal cycles of CO_2 and CH_4 coincid...

  8. Method for indirect quantification of CH4 production via H2O production using hydrogenotrophic methanogens

    Directory of Open Access Journals (Sweden)

    Ruth-Sophie eTaubner

    2016-04-01

    Full Text Available ydrogenotrophic methanogens are an intriguing group of microorganisms from the domain Archaea. They exhibit extraordinary ecological, biochemical, physiological characteristics colorbox{yellow}{and have a huge biotechnological potential}. Yet, the only possibility to assess the methane (CH$_4$ production potential of hydrogenotrophic methanogens is to apply gas chromatographic quantification of CH$_4$.In order to be able to effectively screen pure cultures of hydrogenotrophic methanogens regarding their CH$_4$ production potential we developed a novel method for indirect quantification of colorbox{yellow}{the} volumetric CH$_4$ production rate by measuring colorbox{yellow}{the} volumetric water production rate. This colorbox{yellow}{ } method was established in serum bottles for cultivation of methanogens in closed batch cultivation mode. Water production was colorbox{yellow}{estimated} by determining the difference in mass increase in an isobaric setting.This novel CH$_4$ quantification method is an accurate and precise analytical technique, colorbox{yellow}{which can be used} to rapidly screen pure cultures of methanogens regarding colorbox{yellow}{their} volumetric CH$_{4}$ evolution rate. colorbox{yellow}{It} is a cost effective alternative colorbox{yellow}{determining} CH$_4$ production of methanogens over CH$_4$ quantification by using gas chromatography, especially if colorbox{yellow}{ } applied as a high throughput quantification method. colorbox{yellow}{Eventually, the} method can be universally applied for quantification of CH$_4$ production from psychrophilic, thermophilic and hyperthermophilic hydrogenotrophic methanogens.

  9. Photosynthates as dominant source of CH4 and CO2 in soil water and CH4 emitted to the atmosphere from paddy fields

    Science.gov (United States)

    Minoda, Tomomi; Kimura, Mamoto; Wada, Eitaro

    1996-09-01

    Emission rates of CH4 from paddy soil with and without rice straw applications were measured with pot experiments to estimate the contribution of rice straw to the total CH4 emission during the growth period of rice plants. The CH4 derived from rice straw was calculated to be 44% of the total emission. 13CO2 uptake experiments were also carried out four times from June 30 to September 13, 1994, to estimate the contribution of photosynthesized carbon to CH4 emission. The contribution percentages of photosynthesized carbon to the total CH4 emitted to the atmosphere were 3.8% around June 30, 31% around July 25, 30% around August 19, and 14% around September 13 in the treatment with rice straw applications, and 52% around July 25, 28% around August 19, and 15% around September 13 in the treatment without rice straw applications. They were calculated to be 22% and 29% for the entire growth period in the treatments with and without rice straw applications, respectively. The contribution percentages of photosynthesized carbon to the total CH4 and inorganic carbon (Σ CO2) dissolved in soil water were 1.3%, 30%, 29%, and 34% for dissolved CH4 and 3.0%, 36%, 30% and 28% for dissolved inorganic carbon around June 30, July 25, August l9, and September 13, respectively, in the treatment with rice straw applications. They were 70%, 23%, and 32% for dissolved CH4 and 31%, 16%, and 19% for dissolved inorganic carbon around July 25, August 19, and September 13, respectively, in the treatment without rice straw applications.

  10. Abscesses after appendectomy due to intraoperative loss of fecaliths; Abszesse nach Appendektomie durch intraoperativ verlorene Appendicolithen

    Energy Technology Data Exchange (ETDEWEB)

    Hoermann, M.; Kreuzer, S. [Universitaetsklinik fuer Radiodiagnostik, Vienna (Austria). Abt. chirurgische Faecher; Sacher, P. [UniversitaetsSpital Zuerich (Switzerland). Abt. Kinderchirurgie; Eich, G.F. [UniversitaetsSpital Zuerich (Switzerland). Inst. fuer Diagnostische Radiologie

    2001-08-01

    Objective: Fecaliths appear to predispose a patient to acute appendicitis, abscess formation, and perforation. The number of preoperative radiological evaluations is increasing, although children with suspected perforation still undergo surgery immediately. We report and discuss imaging findings and implications in children with acute appendicitis and fecalithis. Methods: Four children (3 girls, 1 boy; mean age 9 years) underwent surgery for acute appendicitis. Three children underwent sonography and plain radiography before surgery, 1 child was operated without radiological evaluation. After readmission, all 4 children underwent sonography and plain radiography before surgery. Results: In 3 patients a fecalith was diagnosed initially. After uneventful recovery all 4 patients had acute abdominal pain and readmission was necessary. In all 4 patients the escaped fecalith was demonstrated with sonography and plain radiography confirmed surgically. Conclusion: Discussion about the role of imaging in acute appendicitis has concentrated on the diagnostic yield of cross-section techniques. The importance of demonstrating a fecalith, prompting a more thorough intraoperative search has found little attention. The radiologist should also detect and localize a fecalith and should be aware of retained fecaliths as a cause of abscess formation after appendectomy. (orig.) [German] Ziel: Faekolithen praedisponieren Kinder zu akuter Appendizitis und fuehren vermehrt zu Perforation und Abszessen. Wir berichten und diskutieren die Bedeutung der Bildgebung bei Kindern mit Faekolithen und perforierter akuter Appendizitis. Methoden: 4 Kinder (drei Maedchen, ein Junge, Altersmeridian 9 Jahre) wurden wegen perforierter akuter Appendizitis operiert. Drei Kinder erhielten praeoperativ eine Ultraschalluntersuchung und ein Abdomen-Uebersichtsbild. Nach Neuaufnahme wurden nun bei allen Kindern eine Ultraschalluntersuchung und ein Abdomen-Uebersichtsbild angefertigt und neuerlich operiert

  11. Über 20 Jahre ARIADNE. Die frauenspezifische Information und Dokumentation der Österreichischen Nationalbibliothek

    Directory of Open Access Journals (Sweden)

    Lydia Jammernegg

    2016-09-01

    Full Text Available 1992 wurde Ariadne als Fraueninformations- und -dokumentationsstelle an der Österreichischen Nationalbibliothek (ÖNB eingerichtet und arbeitet seitdem sowohl an der dokumentarischen Aufarbeitung des aktuellen frauen-, geschlechterrelevanten und feministischen Literaturbestandes als auch an der Sichtbarmachung des historischen Bestandes der ÖNB zu diesem Themenbereich. In diesem Beitrag geht es darum, die Position von Ariadne im Fraueninformations- und -dokumentationswesen, als Teil der ÖNB, an der Schnittstelle zur Frauenszene, Frauenbewegung, feministischen Szene und zur Frauen- und Geschlechterforschung einer Reflexion zu unterziehen. Nach einer mehr als 20-jährigen Tätigkeit soll ein Rückblick in die Geschichte zeigen, was Ariadne geleistet hat und wo Grenzen liegen, welche Ansprüche und Anliegen Ausgangspunkte für die Arbeit waren und wofür es heute noch frauenspezifische Informations- und Dokumentationseinrichtungen wie Ariadne braucht.

  12. Generation und Familie – über die Ambivalenz eines multistrukturellen Verhältnisses

    Directory of Open Access Journals (Sweden)

    Vera Bollmann

    2008-07-01

    Full Text Available Der Sammelband Generationen und Familien, welcher dem Soziologen Kurt Lüscher zum 70. Geburtstag gewidmet ist, stellt eine kritische Gegenwartsdiagnose des aktuellen Theorie- und Forschungsstandes zu diesem Thema dar. Schon in ihrem Vorwort machen die beiden Herausgeber auf die Diversität und den Facettenreichtum des Familien- und Generationenkonzeptes in modernen Gesellschaften aufmerksam: familiale Generationenbeziehungen werden in ganz unterschiedlicher Weise gelebt, und je nach theoretischer Lesart ergeben sich vielfältige Deutungsmuster. Die Beiträge nähern sich der Verflechtung von Familie, Generation und Gesellschaft sowohl in theoretischer als auch in empirischer Hinsicht. Inhaltlich reihen sie sich in drei übergeordnete Themenblöcke ein: „Generationen, Generationenverhältnisse und Generationenbeziehungen“, „Familie, Alltag und Identität“ und „Soziologie, Recht und Politik”.

  13. Aviation NOx-induced CH4 effect: Fixed mixing ratio boundary conditions versus flux boundary conditions

    Science.gov (United States)

    Khodayari, Arezoo; Olsen, Seth C.; Wuebbles, Donald J.; Phoenix, Daniel B.

    2015-07-01

    Atmospheric chemistry-climate models are often used to calculate the effect of aviation NOx emissions on atmospheric ozone (O3) and methane (CH4). Due to the long (∼10 yr) atmospheric lifetime of methane, model simulations must be run for long time periods, typically for more than 40 simulation years, to reach steady-state if using CH4 emission fluxes. Because of the computational expense of such long runs, studies have traditionally used specified CH4 mixing ratio lower boundary conditions (BCs) and then applied a simple parameterization based on the change in CH4 lifetime between the control and NOx-perturbed simulations to estimate the change in CH4 concentration induced by NOx emissions. In this parameterization a feedback factor (typically a value of 1.4) is used to account for the feedback of CH4 concentrations on its lifetime. Modeling studies comparing simulations using CH4 surface fluxes and fixed mixing ratio BCs are used to examine the validity of this parameterization. The latest version of the Community Earth System Model (CESM), with the CAM5 atmospheric model, was used for this study. Aviation NOx emissions for 2006 were obtained from the AEDT (Aviation Environmental Design Tool) global commercial aircraft emissions. Results show a 31.4 ppb change in CH4 concentration when estimated using the parameterization and a 1.4 feedback factor, and a 28.9 ppb change when the concentration was directly calculated in the CH4 flux simulations. The model calculated value for CH4 feedback on its own lifetime agrees well with the 1.4 feedback factor. Systematic comparisons between the separate runs indicated that the parameterization technique overestimates the CH4 concentration by 8.6%. Therefore, it is concluded that the estimation technique is good to within ∼10% and decreases the computational requirements in our simulations by nearly a factor of 8.

  14. Transpersonale Aspekte von Musik und Imagination in der Traumatherapie

    DEFF Research Database (Denmark)

    Maack, Carola

    2013-01-01

    Guided Imagery and Music nach Helen Bonny (GIM) und ihre Modifikationen haben sich in der Traumatherapie als sehr effektiv herausgestellt. In meinem Vortrag werde ich die Methode und ihre Anwendungen in der Traumatherapie vorstellen. Dabei gehe ich auch auf die Abgrenzung von Imagination im...... personalen und traunspersonalen Raum und deren jeweilige Bedeutung für traumatisierte Menschen in der unterschiedlichen Phasen ihrer Therapie ein. [The Bonny Methode of Guided Imagery and Music (GIM) and its modifications have shown to be quite effective in trauma therapy. In my presentation I will give...

  15. Osteopetrose - aktuelle Diagnostik und Therapie

    Directory of Open Access Journals (Sweden)

    Schulz AS

    2008-01-01

    Full Text Available Unter dem Begriff Osteopetrose wird eine heterogene Gruppe von Krankheiten zusammengefasst, die durch eine pathologisch vermehrte Knochenmasse charakterisiert ist. Diese Osteosklerose basiert in den meisten Fällen auf einem Defekt in der Knochenresorption durch Osteoklasten. Beim Menschen können mehrere Typen unterschieden und nach dem Vererbungsmodus, dem Manifestationsalter, der Schwere der klinischen Symptomatik und nach assoziierten Symptomen klassifiziert werden. Hauptformen sind die infantile "maligne" autosomal rezessive Osteopetrose (ARO, intermediäre autosomal rezessive Formen (IARO und milder verlaufende autosomal dominante Subtypen (ADO. In den letzten Jahren konnten mehrere zur Osteopetrose führende Genveränderungen identifiziert werden. Alle diese Genveränderungen bei humaner Osteopetrose betreffen Proteine, die an der Differenzierung oder Funktion der Osteoklasten beteiligt sind. Da die Osteoklasten sich aus der hämatopoietischen Stammzelle differenzieren, ist die hämatopoietische Stammzelltransplantation eine kurative Therapieoption bei schweren Osteopetroseformen. Allerdings ist diese Therapie mit erheblichen Risiken verbunden. Darüber hinaus sind bestimmte Subtypen der Osteopetrose mit schweren neurologischen Veränderungen assoziiert, die durch eine Stammzelltransplantation nicht positiv beeinflusst werden können. Ein genaues Verständnis der Pathogenese der humanen Osteopetrose ist daher wichtig für die Wahl der richtigen Therapie und gewährt darüber hinaus einen tieferen Einblick in die Physiologie and andere Pathologien des Knochens.

  16. Gedenken, Geschichte und Versöhnung in Südafrika und Zimbabwe

    OpenAIRE

    Marx, Christoph

    2006-01-01

    'Die Gesellschaft Südafrikas hat sich nach der Überwindung der Apartheid mit der Einrichtung einer Wahrheits- und Versöhnungskommission auf eine wichtige öffentliche Debatte über ihre Vergangenheit eingelassen. Der Kontext dieser Debatte und die Vorgabe, dass die Beschäftigung mit der Vergangenheit in die Bildung einer neuen Nation münden solle, führten indes dazu, dass sich neue Formen von Inklusion und Exklusion entwickelten. Da Identität nur über die Betonung von Differenz möglich ist, läs...

  17. From California dreaming to California data: Challenging historic models for landfill CH4 emissions

    Science.gov (United States)

    Improved quantification of diverse CH4 sources at the urban scale is needed to guide local greenhouse gas (GHG) mitigation strategies in the Anthropocene. Herein, we focus on landfill CH4 emissions in California, challenging the current IPCC methodology which focuses on a climate dependency for land...

  18. Geschichtsbezogene und rechtspolitische Polonica im Bücherbestand Gottfried Lengnichs

    Directory of Open Access Journals (Sweden)

    Iwona Imańska

    2017-11-01

    Full Text Available Gottfried Lengnich, der Historiker und Syndikus der Stadt Danzig aus dem 18. Jahrhundert, hinterließ eine Büchersammlung mit über viertausend Büchern, die nach seinem Tode in zwei Auktionen im Juli und November 1774 versteigert werden sollten. Die Auktionskataloge befinden sich in der Staatsbibliothek zu Berlin – Stiftung Preußischer Kulturbesitz und sind auch online zugänglich. Wegen wissenschaftlicher Interessen Lengnichs befanden sich in seiner Bibliothek ca. 600 Polonica-Drucke, die meisten davon waren Abhandlungen im Themenfeld Geschichte, Recht und Politik. Die Analyse dieses Fragments des Bücherbestands Lengnichs bewies, dass der Syndikus eine perfekte Arbeitswerkstatt für sich schuf, indem er die Werke der meisten wichtigsten polnischen und fremden Autoren, die über die Geschichte und die Gesetzgebung Polens und Preußens schrieben, sammelte.

  19. Megafauna and frozen soil: the drivers of atmospheric CH4 dynamics

    Science.gov (United States)

    Zimov, N.; Zimov, S. A.

    2010-12-01

    During the last deglaciation (LD) a strong increase in atmospheric methane (CH4) concentrations occurred simultaneously with a rise in Greenland temperatures indicating that in the north, during this time period, strong CH4 sources “awakened”, as additionally documented by the appearance of a strong gradient between northern (Greenland) and southern (Antarctica) hemisphere atmospheric CH4 concentrations. This rise could not be caused by wetland expansion. A reconstruction of peatland formation dynamics has indicated that wetlands on Earth were few in LD and only actively expanded 10,000 yr BP, after atmospheric CH4 concentrations began to decline. Destabilization of methane clathrates also could not be the source for atmospheric CH4 increase. Geological CH4 (including methane clathrates) has the highest deuterium content (δD) among all of the known sources of CH4 while atmospheric CH4 δD values determined for the LD were record low. To explain recorded atmospheric CH4 and its isotopic dynamics required a strong northern source, which was active only during the LD and that provided very low δD CH4 values. Such a source is permafrost thawing under anaerobic conditions (or better stated soils of mammoth steppe-tundra ecosystems). Permafrost thawing is the strongest, among known, wetland sources (usually over 100g CH4/m2yr) and has a unique isotopic signature (δD = -400 per mil (-338 to -479 per mil), δ13C = -73 per mil (-58 to -99 per mil)). The main sources of atmospheric CH4 have different isotopic signatures (δ13C, δD). The isotopic content of atmospheric CH4 is a simple function of the weight average for all of the sources. Inclusion of permafrost source into a budget model of the atmospheric methane and its isotopes allowed us to reconstruct the dynamics of methane’s main sources. Model indicated geological source to be negligible as in LGM so and in LD and Holocene. During the glaciation, the largest methane source was megafauna, whose 1

  20. Biotic controls on CO2 and CH4 exchange in wetlands - a closed environment study

    DEFF Research Database (Denmark)

    Christensen, TR; Panikov, N; Mastepanov, M

    2003-01-01

    Wetlands are significant sources of the important greenhouse gas CH4. Here we explore the use of an experimental system developed for the determination of continuous fluxes of CO2 and CH4 in closed ecosystem monoliths including the capture of (CO2)-C-14 and (CH4)-C-14 following pulse labelling...... with (CO2)-C-14. We show that, in the ecosystem studied, ebullition (bubble emission) may account for 18 to 50% of the total CH4 emission, representing fluxes that have been difficult to estimate accurately in the past. Furthermore, using plant removal and C-14 labelling techniques, we use the system....../atmosphere interactions, including possible feedback effects on climate change. In recent years much attention has been devoted to ascertaining and subsequently using the relationship between net ecosystem productivity and CH4 emission as a basis for extrapolation of fluxes across large areas. The experimental system...

  1. Stenting und technische Stentumgebung

    Science.gov (United States)

    Hoffstetter, Marc; Pfeifer, Stefan; Schratzenstaller, Thomas; Wintermantel, Erich

    In hoch entwickelten Industrieländern stehen laut Weltgesundheitsorganisation (WHO) Herz-Kreislauf-Erkrankungen und speziell die Koronare Herzkrankheit (KHK) an erster Stelle der Todesursachen. In Deutschland betrug die Zahl der erfassten, an KHK erkrankten Personen ohne Berücksichtigung der Dunkelziffer allein im Jahre 2001 über 473.000. Die KHK war im Jahre 2003 mit 92.673 erfassten Todesfällen immer noch die häufigste Todesursache, obgleich in Deutschland die Häufigkeit der Koronarinterventionen zur Behandlung der KHK zwischen 1984 und 2003 um fast das 80fache von 2.809 auf 221.867 Eingriffe pro Jahr gestiegen ist [1]. Neben der hohen Zahl an Todesfällen haben die betroffenen Personen durch chronische Schmerzen und eingeschränkte körperliche Leistungsfähigkeit zusätzlich eine starke Beeinträchtigung der Lebensqualität [2].In Folge dessen wird die erkrankte Person häufig zum Pflegefall was neben den gesundheitlichen Aspekten auch eine sozioökonomische Komponente in Form der fehlenden Arbeitskraft und den auftretenden Pflegekosten nach sich zieht. Die Kosten für die Behandlung der KHK in Deutschland beliefen sich im Jahre 2002 laut Statistischem Bundesamt auf rund 6,9 Mrd. €. Verglichen mit ähnlichen Zahlen der USA dürfte sich der entstandene Schaden für die deutsche Volkswirtschaft im zwei- bis dreistelligen Milliardenbereich bewegen [3].

  2. Menschewiken in Stockholm vor und nach 1917 / Alexander Kan

    Index Scriptorium Estoniae

    Kan, Alexander

    2005-01-01

    Rootsi sisserännanud menševikest ja bolševikest, nende koostööst rootsi sotsiaaldemokraatidega, vene revolutsionääride tagasipöördumisest Venemaale Veebruarirevolutsiooni järel, repatrieerujaid toetanud Abikomitee tegevusest

  3. Effects of prolonged soil drought on CH4 oxidation in a temperate spruce forest

    Science.gov (United States)

    Borken, W.; Brumme, R.; Xu, Y.-J.

    2000-03-01

    Our objective was to determine potential impacts of changes in rainfall amount and distribution on soil CH4 oxidation in a temperate forest ecosystem. We constructed a roof below the canopy of a 65-year-old Norway spruce forest (Picea abies (L.) Karst.) and simulated two climate change scenarios: (1) an extensively prolonged summer drought of 172 days followed by a rewetting period of 19 days in 1993 and (2) a less intensive summer drought of 108 days followed by a rewetting period of 33 days in 1994. CH4 oxidation, soil matric potential, and soil temperature were measured hourly to daily over a 2-year period. The results showed that annual CH4 oxidation in the drought experiment increased by 102% for the climate change scenario 1 and by 41% for the climate change scenario 2, compared to those of the ambient plot (1.33 kg CH4 ha-1 in 1993 and 1.65 kg CH4 ha-1 in 1994). We tested the relationships between CH4 oxidation rates, water-filled pore space (WFPS), soil matric potential, gas diffusivity, and soil temperature. Temporal variability in the CH4 oxidation rates corresponded most closely to soil matric potential. Employing soil matric potential and soil temperature, we developed a nonlinear model for estimating CH4 oxidation rates. Modeled results were in strong agreement with the measured CH4 oxidation for the ambient (r2 = 0.80) and drought plots (r2 = 0.89) over two experimental years, suggesting that soil matric potential is a highly reliable parameter for modeling CH4 oxidation rate.

  4. Spectrally-resolved UV photodesorption of CH4 in pure and layered ices

    Science.gov (United States)

    Dupuy, R.; Bertin, M.; Féraud, G.; Michaut, X.; Jeseck, P.; Doronin, M.; Philippe, L.; Romanzin, C.; Fillion, J.-H.

    2017-07-01

    Context. Methane is among the main components of the ice mantles of interstellar dust grains, where it is at the start of a rich solid-phase chemical network. Quantification of the photon-induced desorption yield of these frozen molecules and understanding of the underlying processes is necessary to accurately model the observations and the chemical evolution of various regions of the interstellar medium. Aims: This study aims at experimentally determining absolute photodesorption yields for the CH4 molecule as a function of photon energy. The influence of the ice composition is also investigated. By studying the methane desorption from layered CH4:CO ice, indirect desorption processes triggered by the excitation of the CO molecules are monitored and quantified. Methods: Tunable monochromatic vacuum ultraviolet light (VUV) light from the DESIRS beamline of the SOLEIL synchrotron is used in the 7-13.6 eV (177-91 nm) range to irradiate pure CH4 or layers of CH4 deposited on top of CO ice samples. The release of species in the gas phase is monitored by quadrupole mass spectrometry, and absolute photodesorption yields of intact CH4 are deduced. Results: CH4 photodesorbs for photon energies higher than 9.1 eV ( 136 nm). The photodesorption spectrum follows the absorption spectrum of CH4, which confirms a desorption mechanism mediated by electronic transitions in the ice. When it is deposited on top of CO, CH4 desorbs between 8 and 9 eV with a pattern characteristic of CO absorption, indicating desorption induced by energy transfer from CO molecules. Conclusions: The photodesorption of CH4 from pure ice in various interstellar environments is around 2.0 ± 1.0 × 10-3 molecules per incident photon. Results on CO-induced indirect desorption of CH4 provide useful insights for the generalization of this process to other molecules co-existing with CO in ice mantles.

  5. From California dreaming to California data: Challenging historic models for landfill CH4 emissions

    Directory of Open Access Journals (Sweden)

    Kurt Spokas

    2015-06-01

    Full Text Available Abstract Improved quantification of diverse CH4 sources at the urban scale is needed to guide local GHG mitigation strategies in the Anthropocene. Herein, we focus on landfill CH4 emissions in California, challenging the current IPCC methodology which focuses on a climate dependency for landfill CH4 generation (methanogenesis, but does not explicitly consider climate or soil dependencies for emissions. Relying on a comprehensive California landfill database, a field-validated process-based model for landfill CH4 emissions (CALMIM, and select field measurements at 10 California sites with a variety of methods, we support the contrary position: Limited climate dependency for methanogenesis, but strong climate dependency for landfill CH4 emissions. Contrary to the historic IPCC empirical model for methanogenesis with kinetic constants related to climate, we demonstrate a simpler and more robust linear empirical relationship (r2 = 0.85; n=128 between waste mass and landfill biogas recovery [126 × 10-6 Nm3 CH4 hr-1 Mgwaste-1]. More interestingly, there are no statistically significant relationships with climate, site age, or status (open/closed for landfill biogas recovery. The current IPCC methodology does not consider soil or climate drivers for gaseous transport or seasonal methanotrophy in different cover soils. On the other hand, we illustrate strong climate and soil dependencies for landfill emissions—e.g., average intermediate cover emissions below 20 g CH4 m-2 d-1 when the site’s mean annual precipitation is >500 mm y-1. Thereby, for the California landfill CH4 inventory, the highest-emitting sites shift from landfills containing the largest mass of waste to sites dominated by intermediate cover types having a reduced rate of soil CH4 oxidation during the annual cycle. These differences have profound implications for developing more realistic, science-based urban and regional scale GHG inventories for landfill CH4 while reducing

  6. Theorie & Praxis des Lehrer Angst und Stress Test: (Lehramts-)StudentInnen & Lehrkräfte im Vergleich

    OpenAIRE

    Preidel, Julia; Weikamp, Julia; Werhand, Manuela

    2009-01-01

    Der Lehrer Angst und Stress Test (LAST) ist ein Test, der für die Messung von Lehrerangst angedacht ist. Lehrerangst umfasst all jene Ängste von Lehrern, die sie bei der Ausübung ihres Berufs erfahren. Der LAST fragt hierzu nach Reaktionsweisen auf Belastungssituationen, der Stärke zweier Angstkomponenten, nach Faktoren, die zur Angstverstärkung führen und nach Bewältigungsstrategien. Diese Arbeit soll die Testgüte des LAST ein weiteres Mal überprüfen. Diesbezüglich wurde getestet, inwiefe...

  7. Long-term results after fibroid embolization; Langzeitergebnisse nach Myomembolisation

    Energy Technology Data Exchange (ETDEWEB)

    Mueller-Huelsbeck, S. [Medizinischer Klinikverbund Flensburg, Akademisches Lehrkrankenhaus des Universitaetsklinikums Schleswig-Holstein, Abt. Diagnostische und interventionelle Radiologie/Neuroradiologie, Ev.-Luth. Diakonissenanstalt zu Flensburg, Flensburg (Germany)

    2008-07-15

    Fibroids (leiomyoma) are the most frequent benign tumors of the uterus during female reproductive age. In the case of clinical symptoms, uterine artery embolization (UAE) is a well established treatment option for symptomatic fibroids, resulting in promising long-term results. In order to estimate long-term success after UAE, reduction of fibroids and uterus volume is less important than complete improvement and disappearance of fibroid-related symptoms. In addition to a high technical success rate and a low perioperative complication rate, UAE results in high short-term and long-term patient satisfaction (>87%) and improvement of symptoms (>81%). Candidates for UAE should be informed about potential reinterventions in terms of repeated UAE (up to 18% of cases) or surgical treatment options. (orig.) [German] Myome sind die haeufigsten gutartigen soliden Tumoren des weiblichen Genitaltrakts im reproduktiven Alter. Bei klinischen Beschwerden stellt die Uterusarterienembolisation (UAE) zur Therapie des symptomatischen Uterus myomatosus einen fest etabliertes Verfahren dar, das mit viel versprechenden Langzeitergebnissen aufwarten kann. Im Vordergrund der Abschaetzung eines lang andauernden Therapieerfolgs nach UAE stehen weniger die Volumenreduktion eines dominanten Myoms bzw. des gesamten Uterus nach der Behandlung, sondern vielmehr die Besserung oder das voellige Verschwinden der von der Patientin initial vor der UAE angegebenen (myombedingten) Beschwerden. Neben einer hohen technischen Erfolgsrate und geringen perioperativen Komplikationsrate fuehrt die fachkundig durchgefuehrte UAE sowohl im Kurz- als auch Langzeitverlauf zu einem hohen Mass an Patientenzufriedenheit (>87%), verbunden mit einer deutlichen Symptombesserung (>81%). Ueber eine Reintervention (in bis zu ca. 18% der Faelle) im Sinne einer erneuten UAE oder einer operativen Massnahme sollten die Patientinnen allerdings im Vorfeld aufgeklaert werden. (orig.)

  8. Persönlichkeit und Belastungs- bzw. Ressourcenfaktoren. Eine multivariate Betrachtung

    OpenAIRE

    Schneider, Benno

    1997-01-01

    In verschiedenen Modellvorstellungen wird der Zusammenhang zwischen Persönlichkeitseigenschaften und subjektiv erlebtem Streß immer wieder postuliert. Die Forschung ging dabei immer nur einzelnen Variablen nach. Diese Arbeit untersucht den Zusammenhang zwischen einer mehrdimensional erhobenen Persönlichkeit und die mit einem Screeningverfahren erfaßten belastende Ereignisse, soziale Unterstützung und objektiv erlebte positiven oder negative Lebensereignisse. Es wurden über 420 Patienten aus A...

  9. Implementierung, Evaluation und vergleichende Untersuchungen des Powerplex 16 Systems zur quantitativen Chimärismusanalyse

    OpenAIRE

    Joachim, Stefanie

    2010-01-01

    Die allogene Stammzelltransplantation ist ein Verfahren zur Therapie verschiedener maligner und nicht-maligner hämatologischer Erkrankungen. Da es sich um eine sehr aufwendige Therapie handelt, sind Methoden, die den Behandlungsverlauf dokumentieren, wie minimale Resterkrankung und Chimärismusanalyse, essentiell. Eine nach Stammzelltransplantation vollständig vom Spender abgeleitete Hämatopoese ist Voraussetzung für das Engraftment und die Prophylaxe eines Rezidivs der zugrundeliegenden Er...

  10. Ostdeutsche, westdeutsche und ost-west-mobile Mütter im Vergleich

    OpenAIRE

    Grunow, Daniela; Müller, Dana

    2012-01-01

    Am Beispiel des wiedervereinigten Deutschlands zeigt dieser Beitrag, welche Unterschiede in den Erwerbsunterbrechungsdauern von Müttern in Ost- und Westdeutschland bestehen. Empirisch betrachten wir das Rückkehrverhalten nach Erstgeburten im Zeitraum von 1992 bis 2009. In dieser Zeit gelten in Ost- und Westdeutschland gleiche Elternzeit- und Elterngeldgesetze, während sich kulturelle Orientierungen hinsichtlich der Mutterrolle unterscheiden. Unser Vergleich erlaubt deshalb Rückschlüsse auf di...

  11. 371 Exhumierungen : eine Untersuchung aus morphologischer, versicherungsmedizinischer und rechtsmedizinischer Sicht

    OpenAIRE

    Ulm, Kristin

    2008-01-01

    In der vorliegenden Arbeit wurden die Ergebnisse von 371 Exhumierungen aus den Jahren 1967 bis 1998 ausgewertet unter der Fragestellung, ob aussagekräftige morphologische Befunde auch noch nach einer längeren Leichenliegezeit erhoben werden und versicherungsmedizinische Fragen hierdurch beantwortet werden können. Die erhobenen morphologischen Befunde sowohl auf mikroskopischer als auch auf makroskopischer Ebene wurden zu einem Erwartungskatalog zusammengefasst und mit den Ergebnissen der...

  12. Zum Stand und zu den Perspek-tiven der allgemeinsprachlichen ...

    African Journals Online (AJOL)

    Nach einer kurzen Übersicht über die allgemeinsprachlichen zwei-sprachigen Wörterbücher mit Deutsch und Slowenisch werden folgende Wörterbücher näher untersucht: Plet, DebN, DebS, PonsN und PonsS. Im ersten Teil der Wörterbuchanalyse werden der Benutzerbezug, die Wörterbuchbasis, die primär gebuchte ...

  13. Die Darstellung von guten und schlechten Beziehungen in Kinderzeichnungen

    OpenAIRE

    Gramel, Sabine

    2005-01-01

    Nach welchen Kriterien sich Bilder, auf denen Kinder eine positive Beziehung darstellen, von Bildern unterscheiden, auf denen negative Beziehungen dargestellt sind, wurde an einer Stichprobe von 45 Kindern zwischen 4;6 und 11;6 Jahren untersucht. Die Kinder fertigten jeweils ein positives und ein negatives Beziehungsbild an. Es zeigte sich, dass die Kinder in beiden Beziehungskategorien zum großen Teil Gleichaltrige darstellten. Sie benannten für ihre Bilder Kriterien, anhand derer man die po...

  14. Local- and regional-scale measurements of CH4, δ13CH4, and C2H6 in the Uintah Basin using a mobile stable isotope analyzer

    Science.gov (United States)

    Rella, C. W.; Hoffnagle, J.; He, Y.; Tajima, S.

    2015-10-01

    In this paper, we present an innovative CH4, δ13CH4, and C2H6 instrument based on cavity ring-down spectroscopy (CRDS). The design and performance of the analyzer is presented in detail. The instrument is capable of precision of less than 1 ‰ on δ13CH4 with 1 in. of averaging and about 0.1 ‰ in an hour. Using this instrument, we present a comprehensive approach to atmospheric methane emissions attribution. Field measurements were performed in the Uintah Basin (Utah, USA) in the winter of 2013, using a mobile lab equipped with the CRDS analyzer, a high-accuracy GPS, a sonic anemometer, and an onboard gas storage and playback system. With a small population and almost no other sources of methane and ethane other than oil and gas extraction activities, the Uintah Basin represents an ideal location to investigate and validate new measurement methods of atmospheric methane and ethane. We present the results of measurements of the individual fugitive emissions from 23 natural gas wells and six oil wells in the region. The δ13CH4 and C2H6 signatures that we observe are consistent with the signatures of the gases found in the wells. Furthermore, regional measurements of the atmospheric CH4, δ13CH4, and C2H6 signatures throughout the basin have been made, using continuous sampling into a 450 m long tube and laboratory reanalysis with the CRDS instrument. These measurements suggest that 85 ± 7 % of the total emissions in the basin are from natural gas production.

  15. Die linke und die rechte todesauffassung: Zur kritik einer antitotalitären thanatologie

    Directory of Open Access Journals (Sweden)

    Kuljić Todor

    2011-01-01

    Full Text Available Hier sind die tiefere Schichten in der Todesauffassung bei der Ideologien der Linke und der Rechte untersucht und die Frage nach ihren antitotalitären Glei­chsetzung in punkto Betrachtung gestellt. Zu diesem Zweck werden verschiedene Opfersauffassungen und verschiedene Heilshoffnungen, aber auch verschiedene Ideolosierungen des Todes im Faschismus und Sozialismus gelegt, verglichen und in einen breiteren Kontext gestellt. Daraus folgt der starke Kluft zwischen linken und rechten Auffassung von normalen Lebensumständen. Die Herrschaft (nicht der Gott formiert und auf ideologische Weise nützt Angst vom Tod. Für die kritische Theorie ist die Gegenüberstellung von Leben und Tod ein Teil von emanzipatorische Praxis und Kapitalismuskritik. Die dargelegte Kritik der neoliberalen Thanathologie ist ein Teil von dieser Absicht.

  16. Automatic installation of separating 13CH4 from natural CH4, representing a profiled cascade, achieved on the basis of the thermodiffusion column study

    International Nuclear Information System (INIS)

    Ghete, P.

    1976-01-01

    In order to enrich 13 CH 4 from natural CH 4 , an installation, partly automated, has been achieved, using thermodifussion as a separation process for stable isotopes. The thermodifussion columns is original both as construction and solution used for heating the concentric tube. It has been studied the heat transfer properties of the column, the mass transfer and it has been realized an original calculation program concerning the T.D. cascade performances, pointing out an energetical optimum. The experimental results are presented in diagrams each point representing the result of the statistical processing of at least 10 experimental measurements. (author)

  17. A new metal-organic framework for separation of C2H2/CH4 and CO2/CH4 at room temperature

    Science.gov (United States)

    Duan, Xing; Zhou, You; Lv, Ran; Yu, Ben; Chen, Haodong; Ji, Zhenguo; Cui, Yuanjing; Yang, Yu; Qian, Guodong

    2018-04-01

    A 3D microporous metal-organic framework with open Cu2+ sites and suitable pore space, [Cu2(L)(H2O)2]·(H2O)4(DMF)8 (ZJU-15, H4L = 5,5‧-(9H-carbazole-2,7-diyl)diisophthalic acid; DMF = N,N-dimethylformamide; ZJU = Zhejiang University), has been constructed and characterized. The activated ZJU-15a has three different types of cages and exhibits BET surface area of 1660 m2 g-1, and can separate gas mixture of C2H2/CH4 and CO2/CH4 at room temperature.

  18. Assessing diel variation of CH4 flux from rice paddies through temperature patterns

    Science.gov (United States)

    Centeno, Caesar Arloo R.; Alberto, Ma Carmelita R.; Wassmann, Reiner; Sander, Bjoern Ole

    2017-10-01

    The diel variation in methane (CH4) flux from irrigated rice was characterized during the dry and wet cropping seasons in 2013 and 2014 using the eddy covariance (EC) technique. The EC technique has the advantage of obtaining measurements of fluxes at an extremely high temporal resolution (10Hz), meaning it records 36,000 measurements per hour. The EC measurements can very well capture the temporal variations of the diel (both diurnal and nocturnal) fluxes of CH4 and the environmental factors (temperature, surface energy flux, and gross ecosystem photosynthesis) at 30-min intervals. The information generated by this technique is important to enhance our mechanistic understanding of the different factors affecting the landscape scale diel CH4 flux. Distinct diel patterns of CH4 flux were observed when the data were partitioned into different cropping periods (pre-planting, growth, and fallow). The temporal variations of the diel CH4 flux during the dry seasons were more pronounced than during the wet seasons because the latter had so much climatic disturbance from heavy monsoon rains and occasional typhoons. Pearson correlation analysis and Granger causality test were used to confirm if the environmental factors evaluated were not only correlated with but also Granger-causing the diel CH4 flux. Soil temperature at 2.5 cm depth (Ts 2.5 cm) can be used as simple proxy for predicting diel variations of CH4 fluxes in rice paddies using simple linear regression during both the dry and wet seasons. This simple site-specific temperature response function can be used for gap-filling CH4 flux data for improving the estimates of CH4 source strength from irrigated rice production.

  19. Unusually Warm Spring Temperatures Magnify Annual CH4 Losses From Arctic Ecosystems

    Science.gov (United States)

    Goodrich, J. P.; Oechel, W. C.; Gioli, B.; Murphy, P.; Zona, D.

    2015-12-01

    The relatively fast pace of Northern high latitude warming puts the very large permafrost soil C pool at a higher risk of being lost to the atmosphere as CH4. Estimates for the Arctic tundra's contribution to the global wetland CH4 emissions range from 15-27 TgCH4 y-1 (8-14% of total). However, these estimates are largely based on data from the growing season, or from boreal systems underlain by discontinuous permafrost with different physical, hydrological, and biogeochemical dynamics than continuous permafrost zones. Recent data from a transect of eddy covariance flux towers across the North Slope of Alaska revealed the importance of cold season emissions to the annual CH4 budget, which may not correlate with summer flux patterns. However, understanding of the controls and inter-annual variability in fluxes at these different sites is lacking. Here, we present data from ~3 years at 5 tundra ecosystems along this Arctic transect to show the influence of earlier and deeper spring active layer thaw on timing and magnitude of CH4 fluxes. This year's warm spring led to significantly greater thaw depths and lower water tables than the previous year. Substantial CH4 emissions in 2015 were recorded at the wettest sites >20 days earlier than in the more meteorologically normal previous year. Since the soil remained saturated despite a lowered water table, total spring CH4 emissions more than doubled at these wet sites. At the drier sites, soil moisture declined with water table during the warmer spring, resulting in similar emissions to the previous year. However, deeper thaw depths prolonged fall and early winter emissions during the 'zero-curtain' soil temperature freezing phase, particularly at the drier site. In general, warmer spring temperatures in the Arctic may result in large increases in early season CH4 losses at wet sites and prolonged steady losses at the upland sites, enhancing the feedback between changing climate and tundra CH4 emissions at all sites.

  20. OH vibrational activation and decay dynamics of CH4-OH entrance channel complexes

    International Nuclear Information System (INIS)

    Wheeler, Martyn D.; Tsiouris, Maria; Lester, Marsha I.; Lendvay, Gyoergy

    2000-01-01

    Infrared spectroscopy has been utilized to examine the structure and vibrational decay dynamics of CH 4 -OH complexes that have been stabilized in the entrance channel to the CH 4 +OH hydrogen abstraction reaction. Rotationally resolved infrared spectra of the CH 4 -OH complexes have been obtained in the OH fundamental and overtone regions using an IR-UV (infrared-ultraviolet) double-resonance technique. Pure OH stretching bands have been identified at 3563.45(5) and 6961.98(4) cm-1 (origins), along with combination bands involving the simultaneous excitation of OH stretching and intermolecular bending motions. The infrared spectra exhibit extensive homogeneous broadening arising from the rapid decay of vibrationally activated CH 4 -OH complexes due to vibrational relaxation and/or reaction. Lifetimes of 38(5) and 25(3) ps for CH 4 -OH prepared with one and two quanta of OH excitation, respectively, have been extracted from the infrared spectra. The nascent distribution of the OH products from vibrational predissociation has been evaluated by ultraviolet probe laser-induced fluorescence measurements. The dominant inelastic decay channel involves the transfer of one quantum of OH stretch to the pentad of CH 4 vibrational states with energies near 3000 cm-1. The experimental findings are compared with full collision studies of vibrationally excited OH with CH 4 . In addition, ab initio electronic structure calculations have been carried out to elucidate the minimum energy configuration of the CH 4 -OH complex. The calculations predict a C 3v geometry with the hydrogen of OH pointing toward one of four equivalent faces of the CH 4 tetrahedron, consistent with the analysis of the experimental infrared spectra. (c) 2000 American Institute of Physics

  1. BOREAS TGB-1 CH4 Concentration and Flux Data from NSA Tower Sites

    Science.gov (United States)

    Hall, Forrest G. (Editor); Conrad, Sara K. (Editor); Crill, Patrick; Varner, Ruth K.

    2000-01-01

    The BOREAS TGB-1 team made numerous measurements of trace gas concentrations and fluxes at various NSA sites. This data set contains half-hourly averages of ambient methane (CH4) measurements and calculated fluxes for the NSA-Fen in 1996 and the NSA-BP and NSA-OJP tower sites in 1994. The purpose of this study was to determine the CH4 flux from the study area by measuring ambient CH 4 concentrations. This flux can then be compared to the chamber flux measurements taken at the same sites. The data are provided in tabular ASCII files.

  2. BOREAS TGB-1 Soil CH4 and CO2 Profile Data from NSA Tower Sites

    Science.gov (United States)

    Crill, Patrick; Varner, Ruth K.; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOREAS TGB-1 team made numerous measurements of trace gas concentrations and fluxes at various NSA sites. This data set contains methane (CH4) and carbon dioxide (CO2) concentrations in soil profiles from the NSA-OJP, NSA-OBS, NSA-YJP, and NSA-BP sites during the period of 23-May to 20-Sep-1994. The soil gas sampling profiles of CH 4 and CO 2 were completed to quantify controls on CO2 and CH4 fluxes in the boreal forest. The data are provided in tabular ASCII files.

  3. Environment and traffic. Contribution to environmentally compatible projecting and analysis of roads; Umwelt und Verkehr. Beitraege zur umweltvertraeglichen Planung und Beurteilung von Verkehrswegen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The book contains contributions on air pollution abatement, noise and vibration abatement, conservation and landscaping. It addressses experts, who are given information on efficient and low-cost planning of new roads with minimum adverse effects on nature and landscape and minimum pollutant and noise problems. The focus is on noise, as this field is often left out of account in environmental protection considerations. [German] Das Heft beinhaltet eine Zusammenstellung von Beitraegen aus den Fachbereichen der Luftreinhaltung, des Laerm- und Erschuetterungsschutzes sowie des Naturschutzes und der Landschaftspflege. Es soll der Fachwelt Hinweise und Anregungen geben, um Verkehrswege zweckmaessig und kostenguenstig zu planen sowie Eingriffe in die Natur und Landschaft und verkehrsbedingte Einwirkungen von Schadstoffen und Laerm so gering wie moeglich zu halten. Das Thema Laerm dominiert hier ganz bewusst. Wenn auch bei allen Arten der Umweltbeeintraechtigung durch den Verkehr nach weiteren Loesungen gesucht werden muss, besteht im Laermschutz ein besonderer technischer und regelnder Nachholbedarf. (orig.)

  4. Physik für Studenten der Natur- und Technikwissenschaften

    CERN Document Server

    Stroppe, Heribert

    1999-01-01

    Dieses bewährte Lehrbuch vermittelt in kompakter Form einen Überblick über das gesamte physikalische Grundlagenwissen. Die inhaltiche Gliederung nach den Grundmodellen der Physik : Teilchen, Kontinua, Wärme, Felder, Wellen, Quanten, und die didaktische Aufbereitung des Lehrstoffes ermöglichen eine rationelle Wissensaneignung. [...

  5. CH4/air homogeneous autoignition: A comparison of two chemical kinetics mechanisms

    KAUST Repository

    Tingas, Efstathios Al.; Manias, Dimitris M.; Sarathy, Mani; Goussis, Dimitris A.

    2018-01-01

    Reactions contributing to the generation of the explosive time scale that characterise autoignition of homogeneous stoichiometric CH4/air mixture are identified using two different chemical kinetics models; the well known GRI-3.0 mechanism (53

  6. Studies on the adsorption behavior of CO2-CH4 mixtures using activated carbon

    Directory of Open Access Journals (Sweden)

    R. B. Rios

    2013-12-01

    Full Text Available Separation of CO2 from CO2-CH4 mixtures is an important issue in natural gas and biogas purification. The design of such separation processes depends on the knowledge of the behavior of multicomponent adsorption, particularly that of CO2-CH4 mixtures. In this study, we present a series of experimental binary equilibrium isotherms for CO2-CH4 mixtures on an activated carbon at 293 K and compare them with predicted values using the Ideal Adsorption Solution Theory (IAST and the Extended Langmuir (EL model. Even at concentrations of ca. 20% for all binary isotherms, CO2 already presents higher adsorbed amounts with respect to CH4. A maximum selectivity of around 8.7 was observed for a nearly equimolar mixture at 0.1 MPa. The IAST in conjunction with the Toth equation showed slightly better results than IAST using the Langmuir equation and both showed better results than the EL model.

  7. China’s regional CH_4 emissions: Characteristics, interregional transfer and mitigation policies

    International Nuclear Information System (INIS)

    Zhang, Bo; Yang, T.R.; Chen, B.; Sun, X.D.

    2016-01-01

    Highlights: • China’s CH_4 emissions have significant contributions to global climate change. • The total CH_4 emissions in 2010 amount to 44.3 Tg, half from energy activities. • Half of the national total direct emissions are embodied in interregional trade. • 2/3 of the embodied emission transfers via domestic trade are energy-related. • A national comprehensive action plan to reduce CH_4 emissions should be designed. - Abstract: Methane (CH_4), the second largest greenhouse gas emitted in China, hasn’t been given enough attention in the country’s policies and actions for addressing climate change. This paper aims to perform a bottom-up estimation and multi-regional input–output analysis for China’s anthropogenic CH_4 emissions from both production-based and consumption-based insights. As the world’s largest CH_4 emitter, China’s total anthropogenic CH_4 emissions in 2010 are estimated at 44.3 Tg and correspond to 1507.9 Mt CO_2-eq by the lower global warming potential factor of 34. Energy activities as the largest contributor hold about half of the national total emissions, mainly from coal mining. Inherent economic driving factors covering consumption, investment and international exports play an important role in determining regional CH_4 emission inventories. Interregional transfers of embodied emissions via domestic trade are equivalent to half of the national total emissions from domestic production, of which two thirds are energy-related embodied emissions. Most central and western regions as net interregional CH_4 exporters such as Shanxi and Inner Mongolia have higher direct emissions, while the eastern coastal regions as net interregional importers such as Guangdong and Jiangsu always have larger embodied emissions. Since China’s CH_4 emissions have significant contributions to global climate change, a national comprehensive action plan to reduce CH_4 emissions should be designed by considering supply-side and demand

  8. A pan-Arctic synthesis of CH4 and CO2 production from anoxic soil incubations

    Science.gov (United States)

    Treat, C.C.; Natali, Susan M.; Ernakovich, Jessica; Iverson, Colleen M.; Lupasco, Massimo; McGuire, A. David; Norby, Richard J.; Roy Chowdhury, Taniya; Richter, Andreas; Šantrůčková, Hana; Schädel, C.; Schuur, Edward A.G.; Sloan, Victoria L.; Turetsky, Merritt R.; Waldrop, Mark P.

    2015-01-01

    Permafrost thaw can alter the soil environment through changes in soil moisture, frequently resulting in soil saturation, a shift to anaerobic decomposition, and changes in the plant community. These changes, along with thawing of previously frozen organic material, can alter the form and magnitude of greenhouse gas production from permafrost ecosystems. We synthesized existing methane (CH4) and carbon dioxide (CO2) production measurements from anaerobic incubations of boreal and tundra soils from the geographic permafrost region to evaluate large-scale controls of anaerobic CO2 and CH4 production and compare the relative importance of landscape-level factors (e.g., vegetation type and landscape position), soil properties (e.g., pH, depth, and soil type), and soil environmental conditions (e.g., temperature and relative water table position). We found fivefold higher maximum CH4 production per gram soil carbon from organic soils than mineral soils. Maximum CH4 production from soils in the active layer (ground that thaws and refreezes annually) was nearly four times that of permafrost per gram soil carbon, and CH4 production per gram soil carbon was two times greater from sites without permafrost than sites with permafrost. Maximum CH4 and median anaerobic CO2 production decreased with depth, while CO2:CH4 production increased with depth. Maximum CH4 production was highest in soils with herbaceous vegetation and soils that were either consistently or periodically inundated. This synthesis identifies the need to consider biome, landscape position, and vascular/moss vegetation types when modeling CH4 production in permafrost ecosystems and suggests the need for longer-term anaerobic incubations to fully capture CH4 dynamics. Our results demonstrate that as climate warms in arctic and boreal regions, rates of anaerobic CO2 and CH4 production will increase, not only as a result of increased temperature, but also from shifts in vegetation and increased

  9. CH4 emissions from European Major Population Centers: Results from aircraft-borne CH4 in-situ observations during EMeRGe-Europe campaign 2017

    Science.gov (United States)

    Roiger, A.; Klausner, T.; Schlager, H.; Ziereis, H.; Huntrieser, H.; Baumann, R.; Eirenschmalz, L.; Joeckel, P.; Mertens, M.; Fisher, R.; Bauguitte, S.; Young, S.; Andrés Hernández, M. D.

    2017-12-01

    Urban environments represent large and diffuse area sources of CH4 including emissions from pipeline leaks, industrial/sewage treatment plants, and landfills. However, there is little knowledge about the exact magnitude of these emissions and their contribution to total anthropogenic CH4. Especially in the context of an urbanizing world, a better understanding of the methane footprint of urban areas is crucial, both with respect to mitigation and projection of climate impacts. Aircraft-borne in-situ measurements are particularly useful to both quantify emissions from such area sources, as well as to study their impact on the regional distribution. However, airborne CH4 observations downstream of European cities are especially sparse.Here we report from aircraft-borne CH4 in-situ measurements as conducted during the HALO aircraft campaign EMeRGe (Effect of Megacities on the Transport and Transformation of Pollutants on the Regional to Global Scales) in July 2017, which was led by the University of Bremen, Germany. During seven research flights, emissions from a variety of European (Mega)-cities were probed at different altitudes from 3km down to 500m, including measurements in the outflows of London, Rome, Po Valley, Ruhr and Benelux. We will present and compare the CH4 distribution measured downstream of the various studied urban hot-spots. With the help of other trace gas measurements (including e.g. CO2, CO, O3, SO2), observed methane enhancements will be attributed to the different potential source types. Finally, by the combination of in-situ measurements and regional model simulations using the EMAC-MECO(n) model, the contribution of emissions from urban centers to the regional methane budget over Europe will be discussed.

  10. Reticular synthesis of HKUST-like tbo MOFs with enhanced CH4 storage

    KAUST Repository

    Spanopoulos, Ioannis

    2015-12-22

    Successful implementation of reticular chemistry using a judiciously designed rigid octatopic carboxylate organic linker allowed the construction of expanded HKUST-1-like tbo-MOF series with intrinsic strong CH4 adsorption sites. The Cu-analogue displayed a concomitant enhancement of the gravimetric and volumetric surface area with the highest reported CH4 uptake among the tbo family, comparable to the best performing MOFs for CH4 storage. The corresponding gravimetric (BET) and volumetric surface area of 3971 m2 g-1 and 2363 m2 cm-3 represent an increase of respectively 115 % and 47 % in comparison to the corresponding values for the prototypical HKUST-1 (tbo-MOF-1), and 42 % and 20 % higher than tbo-MOF-2. High pressure methane adsorption isotherms revealed a high total gravimetric and volumetric CH4 uptakes, reaching 372 cm3 (STP) g-1 and 221 cm3 (STP) cm-3 respectively at 85 bar and 298 K. The corresponding working capacities between 5-80 bar were found to be 294 cm3 (STP) g-1 and 175 cm3 (STP) cm-3 and are placed among the best performing MOFs for CH4 storage particularly at relatively low temperature (e.g. 326 cm3 (STP) g-1 and 194 cm3 (STP) cm-3 at 258 K). To better understand the structure-property relationship and gain insight on the mechanism accounting for the resultant enhanced CH4 storage capacity, molecular simulation study was performed and revealed the presence of very strong CH4 adsorption sites at the vicinity of the organic linker with similar adsorption energetics as the open metal sites. The present findings supports the potential of tbo-MOFs based on the supermolecular building layer (SBL) approach as an ideal platform to further enhance the CH4 storage capacity via expansion and functionalization of the quadrangular pillars.

  11. How to oxidize atmospheric CH4? - A challenge for the future

    International Nuclear Information System (INIS)

    Chazelas, Bruno; Leger, Alain; Ollivier, Marc

    2006-01-01

    Methane is an active Greenhouse effect gas whose concentration will likely increase in the future. The possible destabilisation of CH 4 clathrates (hydrates) due to anthropogenic climate warming, and the resulting outgasing of methane, could lead to a major increase of the global Greenhouse effect, with dramatic consequences for Humanity. For these reasons, the study of possible countermeasures should be actively considered. Here, we suggest taking advantage of the thermodynamic instability of CH 4 in air, and search for ways to oxidize it

  12. Reticular synthesis of HKUST-like tbo MOFs with enhanced CH4 storage

    KAUST Repository

    Spanopoulos, Ioannis; Tsangarakis, Constantinos; Klontzas, Emmanuel; Tylianakis, Emmanuel; Froudakis, George; Adil, Karim; Belmabkhout, Youssef; Eddaoudi, Mohamed; Trikalitis, Pantelis N.

    2015-01-01

    Successful implementation of reticular chemistry using a judiciously designed rigid octatopic carboxylate organic linker allowed the construction of expanded HKUST-1-like tbo-MOF series with intrinsic strong CH4 adsorption sites. The Cu-analogue displayed a concomitant enhancement of the gravimetric and volumetric surface area with the highest reported CH4 uptake among the tbo family, comparable to the best performing MOFs for CH4 storage. The corresponding gravimetric (BET) and volumetric surface area of 3971 m2 g-1 and 2363 m2 cm-3 represent an increase of respectively 115 % and 47 % in comparison to the corresponding values for the prototypical HKUST-1 (tbo-MOF-1), and 42 % and 20 % higher than tbo-MOF-2. High pressure methane adsorption isotherms revealed a high total gravimetric and volumetric CH4 uptakes, reaching 372 cm3 (STP) g-1 and 221 cm3 (STP) cm-3 respectively at 85 bar and 298 K. The corresponding working capacities between 5-80 bar were found to be 294 cm3 (STP) g-1 and 175 cm3 (STP) cm-3 and are placed among the best performing MOFs for CH4 storage particularly at relatively low temperature (e.g. 326 cm3 (STP) g-1 and 194 cm3 (STP) cm-3 at 258 K). To better understand the structure-property relationship and gain insight on the mechanism accounting for the resultant enhanced CH4 storage capacity, molecular simulation study was performed and revealed the presence of very strong CH4 adsorption sites at the vicinity of the organic linker with similar adsorption energetics as the open metal sites. The present findings supports the potential of tbo-MOFs based on the supermolecular building layer (SBL) approach as an ideal platform to further enhance the CH4 storage capacity via expansion and functionalization of the quadrangular pillars.

  13. Biogeochemical controls on microbial CH4 and CO2 production in Arctic polygon tundra

    Science.gov (United States)

    Zheng, J.

    2016-12-01

    Accurately simulating methane (CH4) and carbon dioxide (CO2) emissions from high latitude soils is critically important for reducing uncertainties in soil carbon-climate feedback predictions. The signature polygonal ground of Arctic tundra generates high level of heterogeneity in soil thermal regime, hydrology and oxygen availability, which limits the application of current land surface models with simple moisture response functions. We synthesized CH4 and CO2 production measurements from soil microcosm experiments across a wet-to dry permafrost degradation gradient from low-centered (LCP) to flat-centered (FCP), and high-centered polygons (HCP) to evaluate the relative importance of biogeochemical processes and their response to warming. More degraded polygon (HCP) showed much less carbon loss as CO2 or CH4, while the total CO2 production from FCP is comparable to that from LCP. Maximum CH4 production from the active layer of LCP was nearly 10 times that of permafrost and FCP. Multivariate analyses identifies gravimetric water content and organic carbon content as key predictors for CH4 production, and iron reduction as a key regulator of pH. The synthesized data are used to validate the geochemical model PHREEQC with extended anaerobic organic substrate turnover, fermentation, iron reduction, and methanogenesis reactions. Sensitivity analyses demonstrate that better representations of anaerobic processes and their pH dependency could significantly improve estimates of CH4 and CO2 production. The synthesized data suggest local decreases in CH4 production along the polygon degradation gradient, which is consistent with previous surface flux measurements. Methane oxidation occurring through the soil column of degraded polygons contributes to their low CH4 emissions as well.

  14. Surface study of platinum decorated graphene towards adsorption of NH_3 and CH_4

    International Nuclear Information System (INIS)

    Rad, Ali Shokuhi; Pazoki, Hossein; Mohseni, Soheil; Zareyee, Daryoush; Peyravi, Majid

    2016-01-01

    To distinguish the potential of graphene sensors, there is a need to recognize the interaction between graphene sheet and adsorbing molecules. We used density functional theory (DFT) calculations to study the properties of pristine as well as Pt-decorated graphene sheet upon adsorption of NH_3 and CH_4 on its surface to exploit its potential to be as gas sensors for them. We found much higher adsorption, higher charge transfer, lower intermolecular distance, and higher orbital hybridizing upon adsorption of NH_3 and CH_4 gas molecules on Pt-decorated graphene compared to pristine graphene. Also our calculations reveal that the adsorption energies on Pt-decorated graphene sheet are in order of NH_3 >CH_4 which could be corresponded to the order of their sensitivity on this modified surface. We used orbital analysis including density of states as well as frontier molecular orbital study for all analyte-surface systems to more understanding the kind of interaction (physisorption or chemisorption). Consequently, the Pt-decorated graphene can transform the existence of NH_3 and CH_4 molecules into electrical signal and it may be potentially used as an ideal sensor for detection of NH_3 and CH_4 in ambient situation. - Highlights: • Pt-decorated graphene was investigated as an adsorbent for NH_3 and CH_4. • Much higher adsorption of NH_3 and CH_4 on Pt-decorated graphene than pristine graphene. • Higher adsorption of NH_3 compared to CH_4 on Pt-decorated graphene. • Pt influences the electronic structure of graphene.

  15. Assessing fugitive emissions of CH4 from high-pressure gas pipelines

    Science.gov (United States)

    Worrall, Fred; Boothroyd, Ian; Davies, Richard

    2017-04-01

    The impact of unconventional natural gas production using hydraulic fracturing methods from shale gas basins has been assessed using life-cycle emissions inventories, covering areas such as pre-production, production and transmission processes. The transmission of natural gas from well pad to processing plants and its transport to domestic sites is an important source of fugitive CH4, yet emissions factors and fluxes from transmission processes are often based upon ver out of date measurements. It is important to determine accurate measurements of natural gas losses when compressed and transported between production and processing facilities so as to accurately determine life-cycle CH4 emissions. This study considers CH4 emissions from the UK National Transmission System (NTS) of high pressure natural gas pipelines. Mobile surveys of CH4 emissions using a Picarro Surveyor cavity-ring-down spectrometer were conducted across four areas in the UK, with routes bisecting high pressure pipelines and separate control routes away from the pipelines. A manual survey of soil gas measurements was also conducted along one of the high pressure pipelines using a tunable diode laser. When wind adjusted 92 km of high pressure pipeline and 72 km of control route were drive over a 10 day period. When wind and distance adjusted CH4 fluxes were significantly greater on routes with a pipeline than those without. The smallest leak detectable was 3% above ambient (1.03 relative concentration) with any leaks below 3% above ambient assumed ambient. The number of leaks detected along the pipelines correlate to the estimated length of pipe joints, inferring that there are constant fugitive CH4 emissions from these joints. When scaled up to the UK's National Transmission System pipeline length of 7600 km gives a fugitive CH4 flux of 4700 ± 2864 kt CH4/yr - this fugitive emission from high pressure pipelines is 0.016% of the annual gas supply.

  16. Ausbildung und Erwartungshaltung

    Science.gov (United States)

    Knoke, Holger

    1997-09-01

    ätzlich mitbringen. Außerdem wird eine kurze Studiendauer vorausgesetzt. Und was für eine Ausbildung erwarten Wirtschaftsunternehmen von Hydrogeologen? Die Antwort auf diese Frage hängt einerseits von der Größe des Unternehmens und andererseits vom Markt mit seinen aktuell zu bearbeitenden Problemen ab. Allen gemein ist der Wunsch nach unternehmerischer Sichtweise und die Bereitschaft, Verantwortung zu übernehmen. Äußerungen von Managern, die Angewandte Geologen nur als Lieferanten von Zahlen (oder Größen) einschätzen, zeigen meines Erachtens, daß beide Seiten nicht die Fachproblematik des anderen erkennen und in ihre Sichtweise umsetzen können. Man kann mit Bedauern über solche Äußerungen hinweggehen und sie als Einzelfälle abtun. Sie zeigen jedoch exemplarisch ein Defizit im Verständnis zwischen Angewandten Geologen und Managern. Deren Ausbildung beruht zumeist auf einer juristischen oder betriebswirtschaftlichen bzw. volkswirtschaftlichen Grundlage. Um juristisch ausgebildeten Entscheidungsträgern eine Maßnahme oder deren Denk- und Entscheidungsweise nachvollzogen werden können. Wenn auf der anderen Seite von einem Angewandten Geologen eine Sanierungsmaßnahme vorgeschlagen wird, die einer Kosten-Nutzenanalyse nicht standhält, zeigt dies fehlende Einblicke in betriebswirtschaftliche Grundkenntnisse. Diese Art von Ausbildung fehlt im Angebot an den Deutschen Universitäten. Eine echte Studienreform müßte als Wahl- oder Wahlpflichtfächer Jura, Betriebswirtschaft und Informatik für alle Angewandten Geowissenschaftler berücksichtigen. Konsequenterweise muß dann auf andere Studieninhalte verzichtet werden, und es ergeben sich daraus eine Reihe von unbequemen Fragen: Was soll als Grundausbildung jeder Geologe wissen, was jeder Hydrogeologe? Kann z. B. ein Hydrogeologe ohne Grundkenntnisse der Ingenieurgeologie und der Lagerstättenkunde leben? Ist es nötig, Sedimentologie, Bodenkunde, Geophysik oder Paläontologie belegt zu haben? Sind Spezialisten in

  17. [Spatiotemporal variations of natural wetland CH4 emissions over China under future climate change].

    Science.gov (United States)

    Liu, Jian-gong; Zhu, Qiu-an; Shen, Yan; Yang, Yan-zheng; Luo, Yun-peng; Peng, Chang-hui

    2015-11-01

    Based on a new process-based model, TRIPLEX-GHG, this paper analyzed the spatio-temporal variations of natural wetland CH4 emissions over China under different future climate change scenarios. When natural wetland distributions were fixed, the amount of CH4 emissions from natural wetland ecosystem over China would increase by 32.0%, 55.3% and 90.8% by the end of 21st century under three representative concentration pathways (RCPs) scenarios, RCP2. 6, RCP4.5 and RCP8.5, respectively, compared with the current level. Southern China would have higher CH4 emissions compared to that from central and northern China. Besides, there would be relatively low emission fluxes in western China while relatively high emission fluxes in eastern China. Spatially, the areas with relatively high CH4 emission fluxes would be concentrated in the middle-lower reaches of the Yangtze River, the Northeast and the coasts of the Pearl River. In the future, most natural wetlands would emit more CH4 for RCP4.5 and RCP8.5 than that of 2005. However, under RCP2.6 scenario, the increasing trend would be curbed and CH4 emissions (especially from the Qinghai-Tibet Plateau) begin to decrease in the late 21st century.

  18. Evaluation of origins of CH4 carbon emitted from rice paddies

    Science.gov (United States)

    Watanabe, Akira; Takeda, Takuya; Kimura, Makoto

    1999-10-01

    Possible carbon sources for CH4 emitted from rice paddies are organic matter applied to the fields, such as rice straw (RS), soil organic matter (SOM), and carbon supplied from rice plants (RP), such as exudates and sloughed tissues. To estimate the contribution of each carbon source to CH4 emission, a pot experiment was conducted using 13C-enriched soil sample and 13C-enriched RS as tracers. The percentage contribution of RP carbon was estimated by subtraction. When RS was applied at a rate corresponding to 6 t ha-1, the percentage contributions of RS, SOM, and RP carbon to CH4 emission throughout the period of rice growth were 42%, 18-21%, and 37-40%, respectively. The values for SOM and RP carbon for the treatment in which RS was not applied were 15-20% and 80-85%, respectively. Seasonal variations in the percentage contribution of soil organic carbon to CH4 emission were small in the range between 13% and 30% for the pots with RS and between 15% and 24% for the pots without RS. In the RS-applied treatment, RS and SOM accounted for almost 100% of the CH4 carbon early in the period of rice growth, while 65-70% of the CH4 emission in the milky stage was derived from RP carbon.

  19. Study on the Promotion Effect of Ionic Liquid on CH4 Hydrate Formation

    International Nuclear Information System (INIS)

    Shin, Ju-Young; Mun, Sungyong; Kang, Seong-Pil; Kim, Kisub

    2013-01-01

    In this study, we investigated the kinetics of gas hydrate formation in the presence of ionic liquid (IL). Hydroxyethyl-methyl-morpholinium chloride (HEMM-Cl) was chosen as a material for the promotion effect test. Phase equilibrium curve for CH 4 hydrate with aqueous IL solution was obtained and its induction time and consumed amount of CH 4 gas were also measured. Aqueous solutions containing 20-20,000 ppm of HEMM-Cl was prepared and studied at 70 bar and 274.15 K. To compare the measured results to those of the conventional promoter, sodium dodecyl sulfate was also tested at the same condition. Result showed that the hydrate equilibrium curve was shifted toward higher pressure and lower temperature region. In addition, the induction time on CH 4 hydrate formation in the presence of IL was not shown. The amount of consumed CH 4 was increased with the whole range of tested concentration of IL and the highest consumption of CH 4 happened at 1,000 ppm of HEMM-Cl. HEMM-Cl induced and enhanced the CH 4 hydrate formation with a small amount of addition. Obtained result is expected to be applied for the development of technologies such as gas storage and transport using gas hydrates

  20. Phase transitions in solid Kr-CH4 solutions and rotational excitations in phase II

    International Nuclear Information System (INIS)

    Bagatskii, M.I.; Mashchenko, D.A.; Dudkin, V.V.

    2007-01-01

    The heat capacity C p of solid Kr-n CH 4 solutions with the CH 4 concentrations n=0.82, 0.86, 0.90 as well as solutions with n=0.90, 0.95 doped with 0.002 O 2 impurity has been investigated under equilibrium vapor pressure over the internal 1-24 K. The (T,n)-phase diagram was refined and the region of two-phase states was determined for Kr-n CH 4 solid solutions. The contribution of the rotational subsystem, C r ot, to the heat capacity of the solutions has been separated. Analysis of C r ot(T) at T 1 and E 2 between the tunnel levels of the A-, T- and A-, E--nuclear-spin species of CH 4 molecules in the orientationally ordered subsystem, and to determine the effective energy gaps E 1 between lowest levels of the A- and T- species. The relations τ(n) and E 1 (n) stem from changes of the effective potential field caused as the replacement of CH 4 molecules by Kr atoms at sites of the ordered sublattices. The effective gaps E L between a group of tunnel levels of the ground-state liberation state and the nearest group of excited levels of the liberation state of the ordered CH 4 molecules in the solutions with n=0.90 (E L =52 K) and 0.95 (E L =55 K) has been estimated

  1. Global Governance und libertärer Paternalismus: Akteure, Normativität und Legitimität

    Directory of Open Access Journals (Sweden)

    Mende Janne

    2016-07-01

    Full Text Available Der libertäre Paternalismus weist ähnliche Bezugspunkte auf wie die Global Governance. Bei beiden handelt es sich um ein Bündel staatlicher und nichtstaatlicher Steuerungsversuche, die auf eine Lösung individueller und gesellschaftlicher Probleme abzielen. Eine Verschränkung der Perspektiven beider Konzepte verhilft zu einer genaueren Konturierung ihrer konzeptuellen und normativen Prämissen und zu einer Diskussion ihrer Engführungen und Stärken. Deutlich wird: Der normative Bezugsrahmen des ‚besseren Lebens‘ für die Einzelne (Nudging oder für die Gesellschaft (Global Governance benötigt jeweils genauere Bestimmungen des Verhältnisses von Freiheit und Struktur. Die Regulierungsfähigkeit staatlicher und nichtstaatlicher Akteure wird durch jeweils offenzulegende Legitimitätsannahmen bestimmt. Aus der Perspektivenverschränkung ergeben sich Fragen nach der Strukturierung von Entscheidungsräumen in Global Governance (Nudging Governance und nach den Kriterien für eine Regulierung des libertären Paternalismus (Governing Nudges. Eine Diskussion dieser Fragen ist unabdingbar für eine reflexive Fundierung der Kritik oder der Weiterentwicklung der Konzepte.

  2. A review of endocrine late effects in children after brain tumor therapy; Endokrinologische Funktionsstoerungen nach Hirntumortherapie im Kindesalter

    Energy Technology Data Exchange (ETDEWEB)

    Marx, M.; Langer, T.; Beck, J.D.; Doerr, H.G. [Erlangen-Nuernberg Univ., Erlangen (Germany). Kinderklinik mit Poliklinik

    1999-07-01

    : In der Regel kommt es als erstes und am haeufigsten zu Stoerungen der Wachstumshormonsekretion. Stoerungen der spontanen Wachstumshormonsektretion wurden bereits nach konventionell fraktionierter Schaedelbestrahlung mit 18 Gy beobachtet. Mit einiger Latenz koennen auch Stoerungen der anderen hypothalamo-hypophysaeren Achsen bis hin zum Panhypopituitarismus auftreten. Die Pubertaet kann verfrueht oder verspaetet beginnen oder ganz ausbleiben. Insbesondere bei Maedchen kommt es nach Hirntumortherapie gehaeuft zur fruehen und im Ablauf beschleunigten Pubertaetsentwicklung, die durch eine akzelerierte Knochenreifung zu einer weiteren Verminderung der Endgroesse fuehrt. Hypothalamo-hypophysaer bedingte Stoerungen der Schilddruesenfunktion und der Nebennierenrindenfunktion sind seltener und werden in der Regel erst nach hypothalamo-hypophysaeren Strahlendosen von ueber 40 Gy beobachtet. Schlussfolgerung: Ueberlebende eines Hinrtumors im Kindesalter muessen als Langzeitueberlebende betrachtet werden, bei denen bereits kurz nach Ende der Tumortherapie die ersten der therapiebedingten Spaetfolgen auftreten. Um fuer den individuellen Patienten eine maximale Lebensqualitaet zu erreichen, ist eine langfristige Betreuung mit enger Kooperation der verschiedenen beteiligten Fachdisziplinen unabdingbar. (orig.)

  3. The c2d Spitzer spectroscopic survey of ices around low-mass young stellar objects. III. CH4

    NARCIS (Netherlands)

    Oberg, Karin I.; Boogert, A. C. Adwin; Pontoppidan, Klaus M.; Blake, Geoffrey A.; Evans, Neal J.; Lahuis, Fred; van Dishoeck, Ewine F.

    2008-01-01

    CH4 is proposed to be the starting point of a rich organic chemistry. Solid CH4 abundances have previously been determined mostly toward high-mass star-forming regions. Spitzer IRS now provides a unique opportunity to probe solid CH4 toward low-mass star-forming regions as well. Infrared spectra

  4. Editorial: Informationstechnische Bildung und Medienerziehung

    Directory of Open Access Journals (Sweden)

    Annemarie Hauf-Tulodziecki

    2001-10-01

    Berücksichtigung der informatischen Perspektive aussehen kann. Dieser Frage gehen die vorliegenden Beiträge aus verschiedenen Blickwinkeln nach. Die Beiträge von Herzig, Schulte und Wagner zeigen einen systematischen Zugang: Bardo Herzig entwickelt mit einem zeichenorientierten Ansatz einen interdisziplinären Zugang zu einem gemeinsamen Medienbegriff. Über die Semiotik wird eine theoretische Grundlage geschaffen, die es ermöglicht, medienpädagogische und informationstechnische Sichtweisen im Bereich der Informations- und Kommunikationstechnologien miteinander zu verbinden. Carsten Schulte untersucht Sichtweisen der Fachwissenschaft und Fachdidaktik Informatik, die medialen Aspekte des Computers berühren, entwickelt hieraus Aufgabenbereiche einer «informatischen Medienbildung» und weist nach, dass mit ihnen die Anforderungen der «medienpädagogischen Aufgabenbereiche» bezogen auf computerbasierte Medien erfüllt werden können. Aus einer eher medienpädagogischen Perspektive beschreibt Wolf-Rüdiger Wagner Anforderungen, durch aus spezifischen Gefahren durch die Informationstechnologien erwachsen: Medienkompetenz als Fähigkeit zum Selbstschutz erfordert (Un- Sicherheitsbewusstsein, das Recht auf informationelle Selbstbestimmung, ein technisches Grundverständnis sowie ein angemessenes Kommunikationsverhalten. Zu vergleichbaren Ergebnissen kommt übrigens auch Klaus Brunnstein in seinem Vortrag bei der Fachtagung «Informatikunterricht und Medienbildung», die im September 2001 stattgefunden hat. Er plädierte für eine drastische Revision der Informatikcurricula: Statt vertiefender Programmierkenntnisse sei die Beherrschbarkeit unsicherer Informationstechniken in den Vordergrund zu stellen. Verantwortlicher Umgang mit diesen Techniken bedeutet die kontrollierte Nutzung, Verständnis der Leistungsfähigkeit und Grenzen von Produkten sowie Kenntnisse der wirtschaftlichen und rechtlichen Rahmenbedingungen (2. Die weiteren Beiträge sind eher als eine

  5. Prognose und Verlauf der Posttraumatischen Belastungsstörung bei Soldaten der Bundeswehr. Längsschnittstudie zur Neuvalidierung des Kölner Risikoindex-Bundeswehr (KRI-Bw)

    OpenAIRE

    Dunker, Sibylle

    2009-01-01

    In einer Längsschnittuntersuchung werden Ausmaß und Verlauf der Posttraumatischen Belastungsstörung (PTBS) bei deutschen Soldaten nach einem Auslandseinsatz erfasst. Die Stichprobe besteht aus 650 Afghanistan-Rückkehrern, die 2-4 Monate und 6 Monate nach dem Auslandseinsatz befragt wurden. Die PTBS-Prävalenz beträgt 6 Monate nach der Rückkehr für die Gesamtstichprobe 1.9-7.5%, für traumatisierte Soldaten 3.7-12.1%. Die intraindividuelle Auswertung zeigt heterogene Symptomverläufe bei traumati...

  6. [Leben im Eismeer - Tauchuntersuchungen zur Biologie arktischer Meerespflanzen und Meerestiere

    Science.gov (United States)

    Lippert; Karsten; Wiencke

    2000-01-01

    Die Maske wird nochmals auf Dichtigkeit überprüft, der Knoten der Sicherungsleine mit zwei halben Schlägen fixiert, dann rutscht die Taucherin von der Eiskante in das kalte Wasser. Eine halbe Stunde vergeht, bevor ihr Kopf wieder aus dem Eisloch auftaucht und sie ein großes Sammelnetz nach oben reicht, gefüllt mit verschiedenen Arten von Makroalgen. Obwohl noch große Flächen des Kongsfjordes im arktischen Spitzbergen zugefroren sind und das Festland von einer dicken Schneedecke bedeckt ist, hat unter Wasser in den Algenwäldern bereits der Sommer und damit die Saison der Meeresbiologen begonnen.

  7. CO2/CH4 Separation by a Mixed Matrix Membrane of Polymethylpentyne/MIL-53 Particles

    Directory of Open Access Journals (Sweden)

    Reza Abedini

    2014-10-01

    Full Text Available The effect of Materials Institute Lavoisier-53 (MIL-53 particles on gas transport properties of polymethylpentyne (PMP was investigated. MIL-53 was added to the polymer matrix with different loadings of 10, 20 and 30 wt%. The properties of MIL-53 and prepared membranes were analyzed through FTIR, SEM and TGA methods. The adsorption of CO2 and CH4 was conducted and analyzed accurately through Langmuir equation to investigate the gas transport properties of membranes. The results from TGA showed that degradation temperature (Td increases significantly with increasing MIL-53 loading. SEM images demonstrated that MIL-53 particles dispersed well in polymer matrix with no considerable agglomeration and no non-selective void formation at polymer/filler interface. In addition, CO2 and CH4 permeability measurement along with calculation of CO2/CH4 selectivity were performed. The results showed that the permeability of gases (especially for CO2 increased significantly by increasing the MIL-53 loading. Additionally, CO2/CH4 selectivity showed an increasing trend with increasing the MIL-53 weight percent. Unlike CH4, the CO2 solubility coefficient increased with increasing the MIL-53 loading because of high free volume of membrane and selective adsorption of CO2 with MIL-53. Despite CO2 solubility enhancement its diffusivity coefficient remained more or less unchanged. The enhancement in CH4 permeability has been mainly attributed to its slight incremental diffusivity due to the membrane's increasingly higher free volume. Finally, a comparison between membranes performance and CO2/CH4 Robeson upper bound showed that, the performance of membranes improved due to the presence of MIL-53 which was very close to the Robeson bound.

  8. Large CO2 and CH4 release from a flooded formerly drained fen

    Science.gov (United States)

    Sachs, T.; Franz, D.; Koebsch, F.; Larmanou, E.; Augustin, J.

    2016-12-01

    Drained peatlands are usually strong carbon dioxide (CO2) sources. In Germany, up to 4.5 % of the national CO2 emissions are estimated to be released from agriculturally used peatlands and for some peatland-rich northern states, such as Mecklenburg-Western Pomerania, this share increases to about 20%. Reducing this CO2 source and restoring the peatlands' natural carbon sink is one objective of large-scale nature protection and restoration measures, in which 37.000 ha of drained and degraded peatlands in Mecklenburg-Western Pomerania are slated for rewetting. It is well known, however, that in the initial phase of rewetting, a reduction of the CO2 source strength is usually accompanied by an increase in CH4 emissions. Thus, whether and when the intended effects of rewetting with regard to greenhouse gases are achieved, depends on the balance of CO2 and CH4 fluxes and on the duration of the initial CH4 emission phase. In 2013, a new Fluxnet site went online at a flooded formerly drained river valley fen site near Zarnekow, NE Germany (DE-Zrk), to investigate the combined CO2 and CH4 dynamics at such a heavily degraded and rewetted peatland. The site is dominated by open water with submerged and floating vegetation and surrounding Typha latifolia.Nine year after rewetting, we found large CH4 emissions of 53 g CH4 m-2 a-1 from the open water area, which are 4-fold higher than from the surrounding vegetation zone (13 g CH4 m-2 a-1). Surprisingly, both the open water and the vegetated area were net CO2 sources of 158 and 750 g CO2 m-2 a-1, respectively. Unusual meteorological conditions with a warm and dry summer and a mild winter might have facilitated high respiration rates, particularly from temporally non-inundated organic mud in the vegetation zone.

  9. Characterization of surface defects in high strength galvannealed steels; Charakterisierung der Oberflaechendefekte in hochfesten, nach dem Verzinken waermebehandelten Staehlen

    Energy Technology Data Exchange (ETDEWEB)

    Hong, M.H. [Automotive Steels Research Center, Technical Research Labs., POSCO, Gwangyang (Korea)

    2004-03-01

    Hot-dip galvannealed steel sheets, in which Fe of the substrate steel diffused into upper coating layer so as to be alloyed with Zn through a galvannealing above 450 C followed by hot-dip galvanizing process, generally show superior corrosion resistance, weldability and paintability. They have been widely used in automobile, construction, appliance industries and others. In particular, many researches have been carrying out to produce defect-free coating for an exposed automotive body panel. In the present study, high strength interstitial-free steel sheets containing Mn and P were galvannealed in an industrial continuous galvanizing line and defects on the coating surface were investigated by optical microscopy, scanning electron microscopy and transmission electron microscopy. It is clear that the quality of the substrate strongly affects galvannealed coating and it is essential to keep clean surface just before immediately dipping into molten Zn pot. (orig.) [German] Feuerverzinkte und danach waermebehandelte Stahlbleche, wo Fe aus dem Substratstahl in die obere Beschichtungsschicht diffundiert wie bei Legieren mit Zn und einer Waermebehandlung von ueber 450 C, gefolgt von einem Feuerverzinkverfahren, zeigen im Allgemeinen hervorragende Korrosionsbestaendigkeit, Schweissbarkeit und Anstreichbarkeit. Sie finden ein breites Einsatzgebiet bei Automobilen, im Bauwesen, in Werkzeugindustrien und anderen. Insbesondere wurde von vielen Forschern versucht, eine fehlerfreie Beschichtung fuer ein ungeschuetztes Karosserieteil herzustellen. In der vorliegenden Arbeit wurden hochfeste porenfreie Stahlbleche mit Mn- und P-Gehalt nach dem Verzinken in einer industriellen Endlos-Verzinkungslinie (CGL) waermebehandelt, wobei die Defekte auf der Schichtoberflaeche lichtmikroskopisch, rasterund transmissionselektronenmikroskopisch untersucht wurden. Klar ist, dass die Qualitaet des Substrats die nach dem Verzinken waermebehandelten Schichten beeinflusst und es ist von grosser

  10. A Monte Carlo study of backscattering effects in the photoelectron emission from CsI into CH$_{4}$ and Ar-CH$_{4}$ mixtures

    CERN Document Server

    Escada, J; Rachinhas, P J B M; Lopes, J A M; Santos, F P; Távora, L M N; Conde, C A N; Stauffer, A D

    2007-01-01

    Monte Carlo simulation is used to investigate photoelectron backscattering effects in the emission from a CsI photocathode into CH4 and Ar-CH4 mixtures for incident monochromatic photons with energies Eph in the range 6.8 eV to 9.8 eV (182 nm to 127 nm), and photons from a continuous VUV Hg(Ar) lamp with a spectral distribution peaked at Eph = 6.7 eV (185 nm), considering reduced applied electric fields E/N in the 0.1 Td to 40 Td range. The addition of CH4 to a noble gas efficiently increases electron transmission and drift velocity, due to vibrational excitation of the molecules at low electron energies. Results are presented for the photoelectron transmission efficiencies f, where f is the fraction of the number of photoelectrons emitted from CsI which are transmitted through the gas as compared to vacuum. The dependence of f on Eph, E/N, and mixture composition is analyzed and explained in terms of electron scattering in the different gas media, and results are compared with available measurements. Electro...

  11. The H2/CH4 ratio during serpentinization cannot reliably identify biological signatures.

    Science.gov (United States)

    Huang, Ruifang; Sun, Weidong; Liu, Jinzhong; Ding, Xing; Peng, Shaobang; Zhan, Wenhuan

    2016-09-26

    Serpentinization potentially contributes to the origin and evolution of life during early history of the Earth. Serpentinization produces molecular hydrogen (H 2 ) that can be utilized by microorganisms to gain metabolic energy. Methane can be formed through reactions between molecular hydrogen and oxidized carbon (e.g., carbon dioxide) or through biotic processes. A simple criterion, the H 2 /CH 4 ratio, has been proposed to differentiate abiotic from biotic methane, with values approximately larger than 40 for abiotic methane and values of serpentinization experiments at 200 °C and 0.3 kbar. However, it is not clear whether the criterion is applicable at a wider range of temperatures. In this study, we performed sixteen experiments at 311-500 °C and 3.0 kbar using natural ground peridotite. Our results demonstrate that the H 2 /CH 4 ratios strongly depend on temperature. At 311 °C and 3.0 kbar, the H 2 /CH 4 ratios ranged from 58 to 2,120, much greater than the critical value of 40. By contrast, at 400-500 °C, the H 2 /CH 4 ratios were much lower, ranging from 0.1 to 8.2. The results of this study suggest that the H 2 /CH 4 ratios cannot reliably discriminate abiotic from biotic methane.

  12. The H2/CH4 ratio during serpentinization cannot reliably identify biological signatures

    Science.gov (United States)

    Huang, Ruifang; Sun, Weidong; Liu, Jinzhong; Ding, Xing; Peng, Shaobang; Zhan, Wenhuan

    2016-09-01

    Serpentinization potentially contributes to the origin and evolution of life during early history of the Earth. Serpentinization produces molecular hydrogen (H2) that can be utilized by microorganisms to gain metabolic energy. Methane can be formed through reactions between molecular hydrogen and oxidized carbon (e.g., carbon dioxide) or through biotic processes. A simple criterion, the H2/CH4 ratio, has been proposed to differentiate abiotic from biotic methane, with values approximately larger than 40 for abiotic methane and values of serpentinization experiments at 200 °C and 0.3 kbar. However, it is not clear whether the criterion is applicable at a wider range of temperatures. In this study, we performed sixteen experiments at 311-500 °C and 3.0 kbar using natural ground peridotite. Our results demonstrate that the H2/CH4 ratios strongly depend on temperature. At 311 °C and 3.0 kbar, the H2/CH4 ratios ranged from 58 to 2,120, much greater than the critical value of 40. By contrast, at 400-500 °C, the H2/CH4 ratios were much lower, ranging from 0.1 to 8.2. The results of this study suggest that the H2/CH4 ratios cannot reliably discriminate abiotic from biotic methane.

  13. Microbial CH4 and N2O consumption in acidic wetlands

    Directory of Open Access Journals (Sweden)

    Steffen eKolb

    2012-03-01

    Full Text Available Acidic wetlands are global sources of the atmospheric greenhouse gases methane (CH4, and nitrous oxide (N2O. Consumption of both atmospheric gases has been observed in various acidic wetlands, but information on the microbial mechanisms underlying these phenomena is scarce. A substantial amount of CH4 is consumed in sub soil by aerobic methanotrophs at anoxic–oxic interfaces (e.g., tissues of Sphagnum mosses, rhizosphere of vascular plant roots. Methylocystis-related species are likely candidates that are involved in the consumption of atmospheric CH4 in acidic wetlands. Oxygen availability regulates the activity of methanotrophs of acidic wetlands. Other parameters impacting on the methanotroph-mediated CH4 consumption have not been systematically evaluated. N2O is produced and consumed by microbial denitrification, thus rendering acidic wetlands as temporary sources or sinks for N2O. Denitrifier communities in such ecosystems are diverse, and largely uncultured and/or new, and environmental factors that control their consumption activity are unresolved. Analyses of the composition of N2O reductase genes in acidic wetlands suggest that acid-tolerant Proteobacteria have the potential to mediate N2O consumption in such soils. Thus, the fragmented current state of knowledge raises open questions concerning methanotrophs and dentrifiers that consume atmospheric CH4 and N2O in acidic wetlands.

  14. Optimisation of expansion liquefaction processes using mixed refrigerant N_2–CH_4

    International Nuclear Information System (INIS)

    Ding, He; Sun, Heng; He, Ming

    2016-01-01

    Highlights: • A refrigerant composition matching method for N_2–CH_4 expansion processes. • Efficiency improvements for propane pre-cooled N_2–CH_4 expansion processes. • The process shows good adaptability to varying natural gas compositions. - Abstract: An expansion process with a pre-cooling system is simulated and optimised by Aspen HYSYS and MATLAB"™. Taking advantage of higher specific refrigeration effect of methane and easily reduced refrigeration temperature of nitrogen, the designed process adopts N_2–CH_4 as a mixed refrigerant. Based on the different thermodynamic properties and sensitivity difference of N_2 and CH_4 over the same heat transfer temperature range, this work proposes a novel method of matching refrigerant composition which aims at single-stage or multi-stage series expansion liquefaction processes with pre-cooling systems. This novel method is applied successfully in propane pre-cooled N_2–CH_4 expansion process, and the unit power consumption is reduced to 7.09 kWh/kmol, which is only 5.35% higher than the global optimised solutions obtained by genetic algorithm. This novel method can fulfil the accomplishments of low energy consumption and high liquefaction rate, and thus decreases the gap between the mixed refrigerant and expansion processes in energy consumption. Furthermore, the high exergy efficiency of the process indicates good adaptability to varying natural gas compositions.

  15. Edge effects on N2O, NO and CH4 fluxes in two temperate forests.

    Science.gov (United States)

    Remy, Elyn; Gasche, Rainer; Kiese, Ralf; Wuyts, Karen; Verheyen, Kris; Boeckx, Pascal

    2017-01-01

    Forest ecosystems may act as sinks or sources of nitrogen (N) and carbon (C) compounds, such as the climate relevant trace gases nitrous oxide (N 2 O), nitric oxide (NO) and methane (CH 4 ). Forest edges, which catch more atmospheric deposition, have become important features in European landscapes and elsewhere. Here, we implemented a fully automated measuring system, comprising static and dynamic measuring chambers determining N 2 O, NO and CH 4 fluxes along an edge-to-interior transect in an oak (Q. robur) and a pine (P. nigra) forest in northern Belgium. Each forest was monitored during a 2-week measurement campaign with continuous measurements every 2h. NO emissions were 9-fold higher than N 2 O emissions. The fluxes of NO and CH 4 differed between forest edge and interior, but not for N 2 O. This edge effect was more pronounced in the oak than in the pine forest. In the oak forest, edges emitted less NO (on average 60%) and took up more CH 4 (on average 177%). This suggests that landscape structure can play a role in the atmospheric budgets of these climate relevant trace gases. Soil moisture variation between forest edge and interior was a key variable explaining the magnitude of NO and CH 4 fluxes in our measurement campaign. To better understand the environmental impact of N and C trace gas fluxes from forest edges, additional and long-term measurements in other forest edges are required. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Decadal changes in CH4 and CO2 emissions on the Alaskan North Slope

    Science.gov (United States)

    Sweeney, C.; Commane, R.; Wofsy, S.; Dlugokencky, E. J.; Karion, A.; Stone, R. S.; Chang, R.; Tans, P. P.; Wolter, S.

    2016-12-01

    Large changes in surface air temperature, sea ice cover and permafrost in the Arctic Boreal Ecosystems (ABE) are significantly impacting the critical ecosystem services and human societies that are dependent on the ABE. In order to predict the outcome of continued change in the climate system of the ABE, it is necessary to look at how past changes in climate have affected the ABE. We look at 30 years of CH4 and 42 years of CO2 observations from the NOAA Global Greenhouse Gas Reference Network site in Barrow, Alaska. By eliminating background trends and only looking at data collected when winds are blowing off the North Slope we find very little change in CH4 enhancements, but significant changes in the CO2 enhancements coming off the tundra. The bulk of both CO2 and CH4 emissions appear to be emitted well after the first snow fall on the North Slope. CO2 emissions are a strongly correlation with summer surface temperatures, while CH4 emissions appear insensitive to the large temperature changes that occurred over the measurement period. These results suggest that CO2, and not CH4 emissions, are a likely pathway for the degradation of permafrost carbon.

  17. Soziologische Wissenskulturen zwischen individualisierter Inspiration und prozeduraler Legitimation. Zur Entwicklung qualitativer und interpretativer Sozialforschung in der deutschen und französischen Soziologie seit den 1960er Jahren

    Directory of Open Access Journals (Sweden)

    Reiner Keller

    2016-01-01

    Full Text Available Wie wissen Soziologinnen und Soziologen, was sie wissen? Trotz der Internationalisierung der Soziologie bestehen nach wie vor starke sprachräumliche Unterschiede in der soziologischen Wissensproduktion, in eingesetzten Theorien, Methoden und Fragestellungen. Der nachfolgende Beitrag erläutert die Entwicklung und Ausprägung der Unterschiedlichkeit soziologischer Wissenskulturen im Hinblick auf den Einsatz qualitativer bzw. interpretativer Ansätze seit den 1960er Jahren in Deutschland und Frankreich. Er stützt sich auf ein von uns 2012-2014 geleitetes Forschungsprojekt und dessen empirische Grundlagen: Dokumentenanalysen und Interviews. Wissenskulturen werden als die Arten und Weisen der Produktion und Legitimation von (hier: soziologischem Wissen verstanden. Diesbezüglich lässt sich von der Erkenntnisproduktion als dem zentralen Handlungsproblem soziologischen Forschens sprechen. Während für die französischsprachige Soziologie diagnostisch von einer Lösung dieses Erkenntnisproblems durch die den Forschenden zugeschriebenen Kompetenzen und Inspirationen ausgegangen werden kann, schiebt sich im deutschsprachigen Raume eine prozedurale Legitimation durch Verfahren in den Vordergrund. Der Beitrag rekonstruiert exemplarisch die Ausgangssituation dieser Entwicklungen um die Wende zu den 1960er Jahren und bettet sie in die weitere Entfaltung der jeweiligen Soziologien ein. Er will damit zur gegenwärtigen Entwicklung einer reflexiven Soziologie beitragen. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1601145

  18. Raman spectroscopic characterization of CH4 density over a wide range of temperature and pressure

    Science.gov (United States)

    Shang, Linbo; Chou, I-Ming; Burruss, Robert; Hu, Ruizhong; Bi, Xianwu

    2014-01-01

    The positions of the CH4 Raman ν1 symmetric stretching bands were measured in a wide range of temperature (from −180 °C to 350 °C) and density (up to 0.45 g/cm3) using high-pressure optical cell and fused silica capillary capsule. The results show that the Raman band shift is a function of both methane density and temperature; the band shifts to lower wavenumbers as the density increases and the temperature decreases. An equation representing the observed relationship among the CH4 ν1 band position, temperature, and density can be used to calculate the density in natural or synthetic CH4-bearing inclusions.

  19. Experimental Equipment Validation for Methane (CH4) and Carbon Dioxide (CO2) Hydrates

    Science.gov (United States)

    Saad Khan, Muhammad; Yaqub, Sana; Manner, Naathiya; Ani Karthwathi, Nur; Qasim, Ali; Mellon, Nurhayati Binti; Lal, Bhajan

    2018-04-01

    Clathrate hydrates are eminent structures regard as a threat to the gas and oil industry in light of their irritating propensity to subsea pipelines. For natural gas transmission and processing, the formation of gas hydrate is one of the main flow assurance delinquent has led researchers toward conducting fresh and meticulous studies on various aspects of gas hydrates. This paper highlighted the thermodynamic analysis on pure CH4 and CO2 gas hydrates on the custom fabricated equipment (Sapphire cell hydrate reactor) for experimental validation. CO2 gas hydrate formed at lower pressure (41 bar) as compared to CH4 gas hydrate (70 bar) while comparison of thermodynamic properties between CH4 and CO2 also presented in this study. This preliminary study could provide pathways for the quest of potent hydrate inhibitors.

  20. Intermolecular Force Field Parameters Optimization for Computer Simulations of CH4 in ZIF-8

    Directory of Open Access Journals (Sweden)

    Phannika Kanthima

    2016-01-01

    Full Text Available The differential evolution (DE algorithm is applied for obtaining the optimized intermolecular interaction parameters between CH4 and 2-methylimidazolate ([C4N2H5]− using quantum binding energies of CH4-[C4N2H5]− complexes. The initial parameters and their upper/lower bounds are obtained from the general AMBER force field. The DE optimized and the AMBER parameters are then used in the molecular dynamics (MD simulations of CH4 molecules in the frameworks of ZIF-8. The results show that the DE parameters are better for representing the quantum interaction energies than the AMBER parameters. The dynamical and structural behaviors obtained from MD simulations with both sets of parameters are also of notable differences.

  1. Mitigating CH4 and N2O emissions from intensive rice production systems in northern Vietnam

    DEFF Research Database (Denmark)

    Tariq, Azeem; Vu, Quynh Duong; Jensen, Lars Stoumann

    2017-01-01

    -growing seasons in northern Vietnam, to evaluate the effectiveness of drainage patterns on methane (CH4) and nitrous oxide (N2O) emissions under farmers’ variable conditions. Two improved drainage practices (pre-planting plus midseason [PM] drainage and early-season plus midseason [EM] drainage) were compared...... with local practices of water management (midseason drainage [M] and conventional continuous flooding (control) [C]) with full residue [F] and reduced residue [R] (local practice of residue management) incorporation. The GHG mitigation potential of water regimes was tested in two water management systems...... (efficient field water management [EWM] system and inefficient field water management [IWM] system). In EWM system, EM resulted an average 14% and 55% reduction in CH4 emissions compared to M with R and F respectively. The EM lowered the CH4 emissions by 67% and 43% compared to C in the EWM and IWM...

  2. Background CH4 and N2O fluxes in low-input short rotation coppice

    Science.gov (United States)

    Görres, Carolyn-Monika; Zenone, Terenzio; Ceulemans, Reinhart

    2016-04-01

    Extensively managed short rotation coppice systems are characterized by low fluxes of CH4 and N2O. However due to the large global warming potential of these trace gases (GWP100: CH4: 34, N2O: 298), such background fluxes can still significantly contribute to offsetting the CO2 uptake of short rotation coppice systems. Recent technological advances in fast-response CH4 and N2O analysers have improved our capability to capture these background fluxes, but their quantification still remains a challenge. As an example, we present here CH4 and N2O fluxes from a short-rotation bioenergy plantation in Belgium. Poplars have been planted in a double-row system on a loamy sand in 2010 and coppiced in the beginning of 2012 and 2014 (two-year rotation system). In 2013 (June - November) and 2014 (April - August), the plantation's CH4 and N2O fluxes were measured in parallel with an eddy covariance tower (EC) and an automated chamber system (AC). The EC had a detection limit of 13.68 and 0.76 μmol m-2 h-1 for CH4 and N2O, respectively. The median detection limit of the AC was 0.38 and 0.08 μmol m-2 h-1 for CH4 and N2O, respectively. The EC picked up a few high CH4 emission events with daily averages >100 μmol m-2 h-1, but a large proportion of the measured fluxes were within the EC's detection limit. The same was true for the EC-derived N2O fluxes where the daily average flux was often close to the detection limit. Sporadically, some negative (uptake) fluxes of N2O were observed. On the basis of the EC data, no clear link was found between CH4 and N2O fluxes and environmental variables. The problem with fluxes within the EC detection limit is that a significant amount of the values can show the opposite sign, thus "mirroring" the true flux. Subsequently, environmental controls of background trace gas fluxes might be disguised in the analysis. As a next step, it will be tested if potential environmental drivers of background CH4 and N2O fluxes at the plantation can be

  3. Early Mars serpentinization-derived CH4 reservoirs, H2 induced warming and paleopressure evolution

    Science.gov (United States)

    Lasue, J.; Chassefiere, E.; Langlais, B.; Quesnel, Y.

    2016-12-01

    CH4 has been observed on Mars both by remote sensing and in situ during the past 15 years. Early Mars serpentinization is one possible abiotic mechanism that could not only produce methane, but also explain the observed Martian remanent magnetic field. Assuming a cold early Mars, a cryosphere could trap such CH4 as clathrates in stable form at depth. We recently estimated the maximum storage capacity of such clathrate layer to be about 2x1019 to 2x1020 moles of methane. Such reservoirs may be stable or unstable, depending on many factors that are poorly constrained: major and sudden geological events such as the Tharsis bulge formation, the Hellas impact or the martian polar wander, could have destabilized the clathrates early in the history of the planet and released large quantities of gas in the atmosphere. Here we estimate the associated amounts of serpentinization-derived CH4 stored in the cryosphere that have been released to the atmosphere at the end of the Noachian and the beginning of the Hesperian. Due to rapid clathrate dissociation and photochemical conversion of CH4 to H2, these episodes of massive CH4 release may have resulted in transient H2-rich atmospheres, at typical levels of 10-20% in a background 1-2 bar CO2 atmosphere. We propose that the early Mars cryosphere had a sufficient CH4 storage capacity to have maintained H2-rich transient atmospheres during a total time period up to several Myr or tens of Myr, having potentially contributed - by collision-induced heating effect of atmospheric H2 - to the formation of valley networks during the late Noachian and early Hesperian.

  4. Sensitizing effects of NOx on CH4 oxidation at high pressure

    DEFF Research Database (Denmark)

    Rasmussen, Christian Lund; Rasmussen, Anja Egede; Glarborg, Peter

    2008-01-01

    The CH4/O2/NOx system is investigated in a laboratory-scale high pressure laminar flow reactor with the purpose of elucidating the sensitizing effects of NOx on CH4 oxidation at high pressures and medium temperatures. Experiments are conducted at 100, 50, and 20 bar, 600-900 K, and stoichiometric...... ratios ranging from highly reducing to oxidizing conditions. The experimental results are interpreted in terms of a detailed kinetic model drawn from previous work of the authors, including an updated reaction subset for the direct interactions of NOx and C1-2 hydrocarbon species relevant...

  5. Botulinumtoxin-A in der Behandlung neurogener Blasenfunktionsstörungen bei Kindern: Funktionelle und histomorphologische Langzeitergebnisse

    Directory of Open Access Journals (Sweden)

    Schulte-Baukloh H

    2004-01-01

    Full Text Available Die etablierte Therapie der neurogenen Detrusorhyperaktivität bei Kindern besteht in der Gabe von Anticholinergika und begleitendem intermittierendem Einmalkatheterismus. Eine hohe Nebenwirkungsrate der Anticholinergika oder eine nicht ausreichende Dämpfung der Detrusoraktivität limitiert jedoch die Anwendung und zwingt nicht selten zu einem operativen Vorgehen. Wir untersuchten deshalb die Wirksamkeit von Botulinumtoxin-A (BTX-A auf die neurogene Detrusorhyperaktivität bei Kindern mit neurogener Blasenfunktionsstörung. Hierzu wurden 24 Kinder (11 Mädchen, 13 Jungen; 2,5–20 (Ø 11,9 Jahre mit maximalem Detrusordruck 40 cm H2O trotz anticholinerger Medikation in die Studie eingeschlossen. Nach urodynamischer Evaluierung wurden gewichtsadaptiert 85–300 U BTX-A (Botox(R zystoskopisch an 30–40 Stellen in den M. detrusor injiziert. Urodynamische Kontrollen erfolgten nach 1, 3 und 6 Monaten. Urodynamisch fand sich ein erhöhtes Reflexvolumen nach 1 Monat um +84 %, nach 3 Monaten um +68 % und nach 6 Monaten um +23 %. Entsprechend verhielten sich die Maximalkapazitäten: +35 % (nach 1 Monat, +23 % (nach 3 Monaten und +36 % (nach 6 Monaten. Die Maximaldrücke veränderten sich im o.g. Zeitraum um –41 %, –22 % bzw. +4 %. Die korrespondierenden Veränderungen der Inkontinenzrate betrug –46 %, –15 % bzw. –13 %. Bei 5 Kindern konnte jedoch auch mit dieser Therapie keine zufriedenstellende Drucksituation sichergestellt werden; nach der daraufhin durchgeführten Blasenaugmentation fanden sich in den Blasenresektaten histomorphologisch typische BTX-A bedingte Veränderungen, die jedoch in ihrer Ausprägung keinen signifikanten Gradienten aufwiesen. Zusammenfassend läßt sich festhalten, daß es nach Botulinumtoxin-A-Injektion in den Detrusormuskel bei der Mehrzahl der Patienten zu einer ausgeprägten und therapeutisch relevanten Verbesserung sämtlicher urodynamischer Parameter bei sehr guter Verträglichkeit des Medikamentes kommt

  6. "Doch wie’s da drin aussieht, geht niemand was an." Musikausübung und politikverständnis bei Hermann Scherchen

    Directory of Open Access Journals (Sweden)

    Lucchesi Joachim

    2015-01-01

    Full Text Available Am Beispiel des deutschen Dirigenten Hermann Scherchen (1891-1966 wird dargelegt, wie sein öffentliches Verschweigen eigener linker und antifaschistischer Position in den Jahren nach 1933 zu negativen Reaktionen und politisch motivierten Angriffen führte.

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

    Directory of Open Access Journals (Sweden)

    Johannes Fromme

    2008-01-01

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

  8. Positive Effekte des Mindestlohns auf Arbeitsplatzqualität und Arbeitszufriedenheit

    OpenAIRE

    Pusch, Toralf; Rehm, Miriam

    2017-01-01

    Über den Zusammenhang zwischen Mindestlöhnen und Änderungen bei der Arbeitsplatzqualität ist bisher wenig bekannt. Nach der Mindestlohneinführung in Deutschland stieg die Arbeitsplatzzufriedenheit insgesamt. Neben höheren Stunden- und Bruttolöhnen und verringerten Arbeitszeiten gibt es als möglichen Grund auch eine arbeitsorganisatorische Aufwertung der Arbeitsplätze. Bei bestehenden Beschäftigungsverhältnissen konnten Hinweise auf Verbesserungen beim Betriebsklima und einer mehr auf Mitarbei...

  9. Teilzeitbeschäftigte in Europa: Arbeitsbedingungen, Familienkontext, Motive und subjektive Bewertungen

    OpenAIRE

    Schulze Buschoff, Karin; Rückert, Jana

    1998-01-01

    Basis dieser deskriptiven und vergleichenden Bestandsaufnahme von Teilzeitbeschäftigungen in den Ländern der Europäischen Union sind aktuelle Individualdaten (Eurobarometer 1995 und 1996). Auf der Grundlage der Ergebnisse der Studie ist eine Bewertung der Arbeitsbedingungen von Teilzeitbeschäftigten in den einzelnen Ländern nach objektiven und subjektiven Maßstäben möglich. Darüber hinaus können im Ländervergleich auch Aussagen über das vorherrschende Rollenbild und mögliche Benachteiligungen...

  10. Standortdebatte: (Gender Mainstreaming und Herrschaftskritik A Debate of Placement: (Gender Mainstreaming and Criticism of Power

    Directory of Open Access Journals (Sweden)

    Eva Sänger

    2004-07-01

    Full Text Available Die Autorinnen des Bandes Feminismus, Gender, Geschlecht der schweizerischen Zeitschrift Widerspruch diskutieren die Chancen und Risiken von Gender-Mainstreaming-Strategien im Horizont des neoliberalen Gesellschaftsumbaus und fragen im Diskussionsteil nach den Erkenntnispotenzialen und herrschaftskritischen Perspektiven der feministischen Theorie bzw. poststrukturalistischer und konstruktivistischer Ansätze.The authors of the volume Feminismus, Gender, Geschlecht of the Swiss journal Widerspruch discuss the prospects and risks of gender-mainstreaming strategies in the context of neoliberal social restructuring. In the discussion section, they consider the potential and critical perspectives of feminist theory, i.e. poststructuralist and constructivist methods.

  11. Zur Beteiligung und Bedeutung von Großeltern in strittigen Sorgerechtsverfahren

    OpenAIRE

    Speidel, Leonie

    2009-01-01

    Die Beteiligung und Bedeutung von Großeltern in strittigen Sorgerechtsverfahren wurde anhand von 28 kinder- und jugendpsychiatrischen Gutachten über 36 Kinder analysiert. Die Beteiligung der Großeltern an familiären Interaktionen sowie ihre vielfältigen Rollen und Funktionen in der Familie nehmen nach der Trennung zu. Ihre Bedeutsamkeit steigt vor allem für ihre Enkel an. Vor der Separation unterstützen die Großeltern die Eltern in finanziellen Bereichen, im Haushalt und stundenweise i...

  12. Zusammenhänge zwischen Cyberbullying und Bullying – erste Ergebnisse aus einer Selbstberichtsstudie

    OpenAIRE

    Wachs, Sebastian; Wolf, Karsten D.

    2011-01-01

    Wenn Lis (2007) Annahme zutrifft, dass das neue Phänomen Cyberbullying nichts anderes ist als „alter Wein in neuen Schläuchen“, dann sind viele Cyberbullies und Cybervictims gleich-zeitig auch Bullies und Victims im realen Leben. Weitere Ziele waren, die Prävalenz von (Cyber-)Bullying zu messen und die Gemeinsamkeiten und Unterschiede beider Formen zu untersuchen. Die Studie wurde als Online-Umfrage nach der CAPI-Methode umgesetzt. Das Sample besteht aus 838 Jugendlichen (von 11-17 Jahren), d...

  13. A combustion setup to precisely reference δ13C and δ2H isotope ratios of pure CH4 to produce isotope reference gases of δ13C-CH4 in synthetic air

    Directory of Open Access Journals (Sweden)

    H. Schaefer

    2012-09-01

    Full Text Available Isotope records of atmospheric CH4 can be used to infer changes in the biogeochemistry of CH4. One factor currently limiting the quantitative interpretation of such changes are uncertainties in the isotope measurements stemming from the lack of a unique isotope reference gas, certified for δ13C-CH4 or δ2H-CH4. We present a method to produce isotope reference gases for CH4 in synthetic air that are precisely anchored to the VPDB and VSMOW scales and have δ13C-CH4 values typical for the modern and glacial atmosphere. We quantitatively combusted two pure CH4 gases from fossil and biogenic sources and determined the δ13C and δ2H values of the produced CO2 and H2O relative to the VPDB and VSMOW scales within a very small analytical uncertainty of 0.04‰ and 0.7‰, respectively. We found isotope ratios of −39.56‰ and −56.37‰ for δ13C and −170.1‰ and −317.4‰ for δ2H in the fossil and biogenic CH4, respectively. We used both CH4 types as parental gases from which we mixed two filial CH4 gases. Their δ13C was determined to be −42.21‰ and −47.25‰ representing glacial and present atmospheric δ13C-CH4. The δ2H isotope ratios of the filial CH4 gases were found to be −193.1‰ and −237.1‰, respectively. Next, we mixed aliquots of the filial CH4 gases with ultrapure N2/O2 (CH4 ≤ 2 ppb producing two isotope reference gases of synthetic air with CH4 mixing ratios near atmospheric values. We show that our method is reproducible and does not introduce isotopic fractionation for δ13C within the uncertainties of our detection limit (we cannot conclude this for δ2H because our system is currently not prepared for δ2H-CH4 measurements in air samples. The general principle of our method can be applied to produce synthetic isotope reference gases targeting δ2H-CH4 or other gas species.

  14. Formation of H2 and CH4 by weathering of olivine at temperatures between 30 and 70°C

    Directory of Open Access Journals (Sweden)

    Crill Patrick

    2011-06-01

    Full Text Available Abstract Hydrocarbons such as CH4 are known to be formed through the Fischer-Tropsch or Sabatier type reactions in hydrothermal systems usually at temperatures above 100°C. Weathering of olivine is sometimes suggested to account for abiotic formation of CH4 through its redox lowering and water splitting properties. Knowledge about the CH4 and H2 formation processes at low temperatures is important for the research about the origin and cause of early Earth and Martian CH4 and for CO2 sequestration. We have conducted a series of low temperature, long-term weathering experiments in which we have tested the CH4 and H2 formation potential of forsteritic olivine. The results show low temperature CH4 production that is probably influenced by chromite and magnetite as catalysts. Extensive analyses of a potential CH4 source trapped in the crystal structure of the olivine showed no signs of incorporated CH4. Also, the available sources of organic carbon were not enough to support the total amount of CH4 detected in our experiments. There was also a linear relationship between silica release into solution and the net CH4 accumulation into the incubation bottle headspaces suggesting that CH4 formation under these conditions could be a qualitative indicator of olivine dissolution. It is likely that minerals such as magnetite, chromite and other metal-rich minerals found on the olivine surface catalyze the formation of CH4, because of the low temperature of the system. This may expand the range of environments plausible for abiotic CH4 formation both on Earth and on other terrestrial bodies.

  15. TV Programme Presentations: Kreuz und Quer

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    TV Programme Presentations: Kreuz und Quer: Im Anfang war das Teilchen-CERN und die Frage nach Gott by ORF (2010) and Faszination Wissen: CERN-LHC by Bayerisher Rundfunk (2010)   ORF’s Kreuz und Quer: Im Anfang war das Teilchen-CERN und die Frage nach Gott presents a debate on science and religion and their relationship. The film by Stefanie Mahler and Niki Popper leads a discussion between physicists and theologians on the basis of such questions as what role does coincidence play vs. what is the human responsibility and whether there is a place for God between all these questions and answers. Even in these modern times, 80% of the mass distributed in the universe is made of an unknown origin. Bayerisher Rundfunk’s Faszination Wissen: CERN-LHC, CERN physicists explain the exciting physics searches underway at the Large Hadron Collider. By colliding protons that have been accelerated to almost the speed of light, the LHC is able to create the conditions that existed just after th...

  16. Effects of the conversion of cropland to forest on the CH4 oxidation capacity in soils.

    Science.gov (United States)

    Bárcena, Teresa G.; D'Imperio, Ludovica; Priemé, Anders; Gundersen, Per; Vesterdal, Lars; Christiansen, Jesper R.

    2013-04-01

    As the second most important greenhouse gas (GHG) in the atmosphere, methane (CH4) plays a central role in global warming. Diverse types of soil have been reported as potential CH4 sinks due to the activity of methane oxidizing bacteria (MOB), underlining the importance of this functional group of microorganisms on a global basis. Agricultural practices are known to negatively affect CH4 oxidation in soil, while afforestation of former agricultural soils has been shown to enhance CH4 oxidation over time. However, knowledge is scarce with regard to the mechanisms driving the process of CH4 oxidation in different land uses. Our aim was to study the changes in CH4 uptake capacity in soils along a land-use change gradient from cropland to forest. We performed an incubation experiment to study the CH4 oxidation capacity of the top mineral soil (0-5 cm and 5-15 cm depth) for sites representing the transition from agriculture to afforestation based on monoculture of three tree species with different stand ages: pedunculate oak (4, 19, 42 and >200 years old), European larch (22 and 41 years old) and Norway spruce (15 and 43 years old). Main soil parameters were also measured to determine differences in soil properties between sites. Methane oxidation rates were related to the abundance of the soil methanotrophic community based on quantitative PCR (qPCR). In addition, we also estimated the abundance of ammonia-oxidizing bacteria (AOB) and archaea (AOA), in order to investigate the link between these two similar functional groups. Although present, the abundance of AOB was under detection limit. The effects and interactions among all measured variables were summarized by Principal Component Analysis (PCA). Along the gradient, CH4 oxidation increased with increasing stand age in both soil layers (ranging from 0-1.3 nmol g-1dw d-1). However, we detected significant differences, in particular between oak and spruce, suggesting a possible tree species effect on the CH4

  17. Kollektivismus, Individualismus und Persönlichkeit als Prädiktoren von Einstellungen gegenüber psychologischer Beratung - Ein Kulturvergleich zwischen deutschen und chinesischen Studierenden

    OpenAIRE

    Schmahl, Anne

    2007-01-01

    Die vorliegende Diplomarbeit beschäftigt sich mit einem Kulturvergleich zwischen deutschen (n=103) und chinesischen Studierenden (n=98) bezüglich ihrer Einstellungen gegenüber psychologischer Beratung. Als Prädiktoren der Einstellungen wurden hierbei zum einen die kulturelle Dimension Individualismus-Kollektivismus nach Hofstede (2005) und zum anderen das Fünf-Faktoren-Modell der Persönlichkeit (FFM) herangezogen. Der Einfluss der Persönlichkeit auf die Einstellungen gegenüber psychologischer...

  18. Sinnvolle Lebensführung im Spannungsfeld von Risiko und Sicherheit Die Ethik der Risikominimierung im Lichte von Kierkegaards und Nietzsches Kritik der Moderne

    Directory of Open Access Journals (Sweden)

    Hüsch Sebastian

    2016-07-01

    Full Text Available Der Beitrag betrachtet die für die Gegenwartsgesellschaft charakteristische Orientierung an Sicherheit und Risikovermeidung vor dem Hintergrund der Reflexionen Søren Kierkegaards und Friedrich Nietzsches bezüglich der Abgründigkeit der menschlichen Existenz. Die Untersuchung wirft die Frage auf, ob die Suche nach einem im alltäglichen Sinne verstandenen „guten Leben“ letzten Endes zu Lasten der Möglichkeiten einer als sinnhaft erlebten Existenz geht.

  19. Frauen im Netz weltweit – ausgegrenzt und mittendrin

    Directory of Open Access Journals (Sweden)

    Sigrid Peuker

    2003-03-01

    Full Text Available Mit dem Global Center for Women’s Studies and Politics (GLOW ist das Feministische Institut der Heinrich-Böll-Stiftung 1998 online gegangen. Mit diesem Schritt wurden Fragen nach den Möglichkeiten und Grenzen sowie nach den Gestaltungsräumen virtueller Kommunikation für Frauen zentral. Mit feminist_spaces. Frauen im Netz. Diskurse – Communities – Visionen, legt die Heinrich-Böll-Stiftung zusammen mit dem Feministischen Institut Antworten aus internationaler Perspektive vor. Das Buch geht auf die gleichnamige zweitätige Konferenz in Berlin im November 2001 zurück.

  20. Regional scale variations of atmospheric CO2 and CH4 from satellite observation

    International Nuclear Information System (INIS)

    Ru, F; Lei, L; Guan, X; Bu, R; Qi, J

    2014-01-01

    To identify the sources, sinks and changes of atmospheric CO 2 and CH 4 , this study investigates the spatio-temporal changes of atmospheric CO 2 and CH 4 concentration on the regional scale by the satellite observations. In this paper, choosing the land region of China as the study area, we investigate the spatio-temporal changes of atmospheric CO 2 and CH 4 concentrations using the data of the CO 2 dry air mixing ratio (XCO 2 ), and the CH 4 dry air mixing ratio (XCH 4 ), retrieved by the Greenhouse Gases Observing Satellite (GOSAT) from Jan. 2010 to Dec. 2012. The results show that (1) both XCO 2 and XCH 4 show higher concentrations in southeastern regions than that in the northwestern, and tend to yearly increasing from 2010 to 2013; (2) XCO 2 shows obvious seasonal change with higher values in the spring than that in summer. The seasonal peak-to-peak amplitude is 8 ppm and the annual growth is about 2 ppm. XCH 4 , however, does not show a seasonal change; (3) With regard to different land-use backgrounds, XCO 2 shows larger concentrations over the areas of urban agglomeration than that over the grasslands and deserts, and XCH 4 shows lower concentrations over deserts than that over the Yangtze River Delta region and Sichuan Basin

  1. Tidal influence on the sea-to-air transfer of CH4 in the coastal ocean

    International Nuclear Information System (INIS)

    Hahm, Doshik; Kim, Guebuem; Lee, Yong-Woo; Nam, Sungh-Yun; Kim, Kyung-Ryul; Kim, Kuh

    2006-01-01

    We obtained real-time monitoring data of water temperature, salinity, wind, current, CH 4 and other oceanographic parameters in a coastal bay in the southern sea of Korea from July 8 to August 15, 2003, using an environmental monitoring buoy. In general, the transfer velocity of environmental gases across the air-sea interface is obtained exclusively from empirical relationships with wind speeds. However, our monitoring data demonstrate that the agitation of the aqueous boundary layer is controlled significantly by tidal turbulence, similar to the control exercised by wind stress in the coastal ocean. The sea-to-air transfer of CH 4 is enhanced significantly during spring tide due to an increase in the gas transfer velocity and vertical CH 4 transport from bottom water to the surface layer. Thus, our unique time-series results imply that the sea-to-air transfer of gases, such as CH 4 , DMS, DMHg, N 2 O, CO 2 and 222 Rn, from highly enriched coastal bottom waters, is controlled not only by episodic wind events but also by regular tidal turbulence in the coastal ocean

  2. The global variation of CH4 and CO as seen by SCIAMACHY

    NARCIS (Netherlands)

    Straume, A.G.; Schrijver, H.; Gloudemans, A.M.S.; Houweling, S.; Aben, I.; Maurellis, A.N.; de Laat, A.T.J.; Kleipool, Q.; Lichtenberg, G.; van Hees, R.; Meirink, J.F.; Krol, M.

    2005-01-01

    The methane (CH4) and carbon monoxide (CO) total columns retrieved from SCIAMACHY's near-infrared channel 8 have been compared to satellite measurements by the MOPITT instrument and chemistry transport model calculations (TM3). Results from the SRON retrieval algorithm IMLM (v5.1) are presented here

  3. Accurate quantum calculations of the reaction rates for H/D+ CH4

    NARCIS (Netherlands)

    Harrevelt, R. van; Nyman, G.; Manthe, U.

    2007-01-01

    In previous work [T. Wu, H. J. Werner, and U. Manthe, Science 306, 2227 (2004)], accurate quantum reaction rate calculations of the rate constant for the H+CH4 -> CH3+H-2 reaction have been presented. Both the electronic structure calculations and the nuclear dynamics calculations are converged with

  4. What affects CH4/CO2 ratio in cow’s breath

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Weisbjerg, Martin Riis; Madsen, Jørgen

    2013-01-01

    under farm management control. CO2 is released largely from microbial decay or burning of plant litter and soil organic matter. CH4 is produced when organic materials decompose under anoxic conditions, notably from fermentative digestion by ruminant livestock, stored manures, wetlands and rice grown...

  5. Presumed PDF modeling of microjet assisted CH4–H2/air turbulent flames

    International Nuclear Information System (INIS)

    Chouaieb, Sirine; Kriaa, Wassim; Mhiri, Hatem; Bournot, Philippe

    2016-01-01

    Highlights: • Microjet assisted CH 4 –H 2 /air turbulent flames are numerically investigated. • Temperature, species and soot are well predicted by the Presumed PDF model. • An inner flame is identified due to the microjet presence. • The addition of hydrogen to the microjet assisted flames enhances mixing. • Soot emission is reduced by 36% for a 10% enriched microjet assisted flame. - Abstract: The characteristics of microjet assisted CH 4 –H 2 /air flames in a turbulent mode are numerically investigated. Simulations are performed using the Computational Fluid Dynamics code Fluent. The Presumed PDF and the Discrete Ordinates models are considered respectively for combustion and radiation modeling. The k–ε Realizable model is adopted as a turbulence closure model. The Tesner model is used to calculate soot particle quantities. In the first part of this paper, the Presumed PDF model is compared to the Eddy Dissipation model and to slow chemistry combustion models from literature. Results show that the Presumed PDF model predicts correctly thermal and species fields, as well as soot formation. The effect of hydrogen enrichment on CH 4 /air confined flames under the addition of an air microjet is investigated in the second part of this work. The found results show that an inner flame was identified due to the air microjet for the CH 4 –H 2 /air flames. Moreover, the increase of hydrogen percentage in the fuel mixture leads to mixing enhancement and consequently to considerable soot emission reduction.

  6. Diurnal and seasonal variations in CH4 emission from various freshwater wetlands

    International Nuclear Information System (INIS)

    Kim, J.; Kim, J.-W.; Verma, B.; Shurpali, N.J.; Harazono, Y.; Miyata, A.; Yun, J.-I.; Tanner, B.

    2000-01-01

    Recent evidence indicates that future increases in atmospheric CO2 concentration may lead to significant increases in methane emissions from wetlands. Based on the concurrent eddy covariance measurements of CH4 and ecosystem production in freshwater wetlands. Also, we briefly discuss the current concerns of the micrometeorological community on the long-term monitoring of these greenhouse gases. 16 refs

  7. Linking soil O2, CO2, and CH4 concentrations in a wetland soil

    DEFF Research Database (Denmark)

    Elberling, Bo; Jensen, Louise Askær; Jørgensen, Christian Juncher

    2011-01-01

    and CH4 were measured in the laboratory during flooding of soil columns using a combination of planar O2 optodes and membrane inlet mass spectrometry. Microsensors were used to assess apparent diffusivity under both field and laboratory conditions. Gas concentration profiles were analyzed...... plants tissue on soil gas dynamics and greenhouse gas emissions following marked changes in water level....

  8. CO2 Reforming of CH4 by Atmospheric Pressure Abnormal Glow Plasma

    International Nuclear Information System (INIS)

    Chen Qi; Dai Wei; Tao Xumei; Yu Hui; Dai Xiaoyan; Yin Yongxiang

    2006-01-01

    A novel plasma atmospheric pressure abnormal glow discharge was used to investigate synthesis gas production from reforming methane and carbon dioxide. Special attentions were paid to the discharge characteristics and CH 4 , CO 2 conversion, H 2 , CO selectivity, and ratio of H 2 /CO varied with the changing of discharging power, the total flux, and the ratio of CH 4 /CO 2 . Experiments were performed in wider operation variables, the discharging power of 240 to 600 W, the CH 4 /CO 2 of 0.2 to 1.0 and the total flux of 140 to 500 mL/min. The experiments showed that the conversion of CH 4 and CO 2 was up to 91.9% and 83.2%, the selectivity of CO and H 2 was also up to 80% and 90% and H 2 /CO mole ratio was 0.2 to 1.2, respectively. A brief analysis for discharge characteristics and the experimental results were given

  9. BOREAS TGB-1/TGB-3 CH4 Chamber Flux Data over the NSA Fen

    Science.gov (United States)

    Bubier, Jill L.; Moore, Tim R.; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOREAS TGB-3 team collected methane (CH4) chamber flux measurements at the NSA fen site during May-September 1994 and June-October 1996. Gas samples were extracted approximately every 7 days from chambers and analyzed at the NSA lab facility. The data are provided in tabular ASCII files.

  10. Assessing fugitive emissions of CH4 from high-pressure gas pipelines in the UK

    Science.gov (United States)

    Clancy, S.; Worrall, F.; Davies, R. J.; Almond, S.; Boothroyd, I.

    2016-12-01

    Concern over the greenhouse gas impact of the exploitation of unconventional natural gas from shale deposits has caused a spotlight to be shone on to the entire hydrocarbon industry. Numerous studies have developed life-cycle emissions inventories to assess the impact that hydraulic fracturing has upon greenhouse gas emissions. Incorporated within life-cycle assessments are transmission and distribution losses, including infrastructure such as pipelines and compressor stations that pressurise natural gas for transport along pipelines. Estimates of fugitive emissions from transmission, storage and distribution have been criticized for reliance on old data from inappropriate sources (1970s Russian gas pipelines). In this study, we investigate fugitive emissions of CH4 from the UK high pressure national transmission system. The study took two approaches. Firstly, CH4 concentration is detected by driving along roads bisecting high pressure gas pipelines and also along an equivalent distance along a route where no high pressure gas pipeline was nearby. Five pipelines and five equivalent control routes were driven and the test was that CH4 measurements, when adjusted for distance and wind speed, should be greater on any route with a pipe than any route without a pipe. Secondly, 5 km of a high pressure gas pipeline and 5 km of equivalent farmland, were walked and soil gas (above the pipeline where present) was analysed every 7 m using a tunable diode laser. When wind adjusted 92 km of high pressure pipeline and 72 km of control route were drive over a 10 day period. When wind and distance adjusted CH4 fluxes were significantly greater on routes with a pipeline than those without. The smallest leak detectable was 3% above ambient (1.03 relative concentration) with any leaks below 3% above ambient assumed ambient. The number of leaks detected along the pipelines correlate to the estimated length of pipe joints, inferring that there are constant fugitive CH4 emissions from

  11. Stabilität und Frieden? Ehebeziehungen im Transformationsprozeß Stability and Peace? Changing Relationships Between Husbands and Wives

    Directory of Open Access Journals (Sweden)

    Martina Ritter

    2001-03-01

    Full Text Available In der sehr guten Studie, die auf der Kooperation von amerikanischen und russischen Forscherinnen beruht, werden die ehelichen Beziehungen im gegenwärtigen Rußland diskutiert. Nach einer kontextuellen Einbettung in eine historische Reflexion über die Entwicklung von Ehe und Familie in Rußland und der Sowjetunion und nach transformationstheoretischen Überlegungen werden Themen wie Geschlechterbilder, Arbeitsteilung, Ehe-Qualität und Gewalt mit Hilfe quantitativer Methoden analysiert.In this exceedingly interesting study, American and Russian researchers discuss the relationships between husbands and wives in Russia today. Following an outline of the historical development of marriage and family in Russia and the Soviet Union and some reflexions on the theory of transformation, the book presents analyses of issues like gender attitudes, division of labour, marital quality and abuse. These are carried out on the basis of methods of quantitative empirical research.

  12. Einleitung: Jahrbuch Medienpädagogik 5. Evaluation und Analyse

    Directory of Open Access Journals (Sweden)

    Ben Bachmair

    2017-09-01

    Full Text Available Evaluationsmethoden für E-Learning, Forschungsmethoden zur Mediennutzung und zur Analyse von Medienkulturen sind Gegenstand dieses Jahrbuchs Medienpädagogik. Dabei reicht das Spektrum der Medien von Fernsehen über Video bis zum Internet. Die Auswahl dieses Themenschwerpunkts kommt dabei nicht von ungefähr. Zum einen hat wissenschaftliche Medienforschung bereits eine lange Tradition und ist in vielen Disziplinen etabliert. Forschungsmethoden lieferten der medienpädagogischen Praxis empirisch fundierte Ergebnisse und Instrumente. Forschungsdesigns und Methodologien wurden entwickelt, um Mediennutzungsverhalten und Medienwirkungen zu erklären, Evaluationsmethoden eingesetzt, um Lernprozesse zu beurteilen. Zum anderen gewinnen Qualitätssicherung und Leistungsmessungen im Bildungssystem generell immer mehr an Bedeutung. In den Ergebnissen aktueller Evaluationen zeigen sich Bestrebungen nach Qualität von Bildungs- und Lernprozessen. Empirische Forschung kommt die Aufgabe zu medienpädagogische Wirkungsgrade und Zielerreichung zu überprüfen und zu kontrollieren. Quantitative Forschungsmethoden ermöglichen es Mediennutzungsverhalten bestimmter Zielgruppen in Wechselwirkung mit Programmstrukturen und -inhalten zu ermitteln. Nutzungsmuster von Medienangeboten – vor allem bei Kindern und Jugendlichen – sind auch bei der Entwicklung medienpädagogischer Ansätze wichtig. Qualitative Medienforschung dient als Planungsinstrument für medienpädagogische Konzeptionen sowie für medienpädagogische Praxis und hilft bei der Entwicklung neuer, mehr als bisher an inhaltlichen Kriterien orientierter Angebote eingesetzt werden. Eine der zentralen Fragestellungen war und ist dabei, mit welchen kognitiven und ästhetischen Vermittlungsformen die Inhalte einer Sendung am besten kommuniziert werden können. Dies ist zugleich eine der Grundfragen im Hinblick auf den Medieneinsatz in pädagogisch orientierten Lernprozessen (vgl. Dichanz 1998.

  13. Standortbestimmungen der feministischen Film- und TV-Wissenschaft Assessing the Position of Feminist Film and Television Scholarship

    Directory of Open Access Journals (Sweden)

    Tanja Maier

    2005-07-01

    Full Text Available Der vorliegende Band versammelt zeitgenössische Perspektiven und Ansätze feministischer Film- und TV-Wissenschaften. In vier Kapiteln werden Fragen nach visuellen Praxen, dem ‚Frühen Kino‘, nach Genre und Geschlecht sowie Räumen des Fernsehens diskutiert. Die Themen und Aspekte reichen von Publikumstheorien, Fragen nach dem Verhältnis von Medialität und Geschlecht, der Wahrnehmungsgeschichte des Films bis hin zu Fragen der Intermedialität oder nach der Bedeutung des Feminismus im (frühen Kino und im Fernsehen.The volume at hand collects contemporary perspectives on and approaches to feminist film and television studies. Questions as to visual praxis, early cinema, genre and gender, and the space of television are discussed in four chapters. The topics and aspects span audience theory, questions as to the relationship between mediality and gender, the history of perception of film, questions of intermediality, and the meaning of feminism in (early cinema and television.

  14. Study of atmospheric CH4 mole fractions at three WMO/GAW stations in China

    Science.gov (United States)

    Fang, Shuang-Xi; Zhou, Ling-Xi; Masarie, Kenneth A.; Xu, Lin; Rella, Chris W.

    2013-05-01

    CH4 mole fractions were continuously measured from 2009 to 2011 at three WMO/GAW stations in China (Lin'an, LAN; Longfengshan, LFS; and Waliguan, WLG) using three Cavity Ring Down Spectroscopy instruments. LAN and LFS are GAW regional measurement stations. LAN is located in China's most economically developed region, and LFS is in a rice production area (planting area > 40,000 km2). WLG is a global measurement station in remote northwest China. At LAN, high methane mole fractions are observed in all seasons. Surface winds from the northeast enhance CH4 values, with a maximum increase of 32 ± 15 ppb in summer. The peak to peak amplitude of the seasonal cycle is 77 ± 35 ppb. At LFS, the diurnal cycle amplitude is approximately constant throughout the year except summer, when a value of 196 ± 65 ppb is observed. CH4 values at LFS reach their peak in July, which is different from seasonal variations typically observed in the northern hemisphere. CH4 mole fractions at WLG show both the smallest values and the lowest variability. Maximum values occur during summer, which is different from other northern hemisphere WMO/GAW global stations. The seasonal cycle amplitude is 17 ± 11 ppb. The linear growth rates at LAN, LFS, and WLG are 8.0 ± 1.2, 7.9 ± 0.9, and 9.4 ± 0.2 ppb yr-1, respectively, which are all larger than the global mean over the same 3 year period. Results from this study attempt to improve our basic understanding of observed atmospheric CH4 in China.

  15. Flask sample measurements for CO2, CH4 and CO using cavity ring-down spectrometry

    Science.gov (United States)

    Wang, J.-L.; Jacobson, G.; Rella, C. W.; Chang, C.-Y.; Liu, I.; Liu, W.-T.; Chew, C.; Ou-Yang, C.-F.; Liao, W.-C.; Chang, C.-C.

    2013-08-01

    In recent years, cavity ring-down spectrometry (CRDS) has been demonstrated to be a highly sensitive, stable and fast analytical technique for real-time in situ measurements of greenhouse gases. In this study, we propose the technique (which we call flask-CRDS) of analyzing whole air flask samples for CO2, CH4 and CO using a custom gas manifold designed to connect to a CRDS analyzer. Extremely stable measurements of these gases can be achieved over a large pressure range in the flask, from 175 to 760 Torr. The wide pressure range is conducive to flask sample measurement in three ways: (1) flask samples can be collected in low-pressure environments (e.g. high-altitude locations); (2) flask samples can be first analyzed for other trace gases with the remaining low-pressure sample for CRDS analysis of CO2, CH4 and CO; and (3) flask samples can be archived and re-analyzed for validation. The repeatability of this method (1σ of 0.07 ppm for CO2, 0.4 ppb for CH4, and 0.5 ppb for CO) was assessed by analyzing five canisters filled with the same air sample to a pressure of 200 Torr. An inter-comparison of the flask-CRDS data with in-situ CRDS measurements at a high-altitude mountain baseline station revealed excellent agreement, with differences of 0.10 ± 0.09 ppm (1σ) for CO2 and 0.9 ± 1.0 ppb for CH4. This study demonstrated that the flask-CRDS method was not only simple to build and operate but could also perform highly accurate and precise measurements of atmospheric CO2, CH4 and CO in flask samples.

  16. Inverse modelling of national and European CH4 emissions using the atmospheric zoom model TM5

    Directory of Open Access Journals (Sweden)

    P. Bergamaschi

    2005-01-01

    Full Text Available A synthesis inversion based on the atmospheric zoom model TM5 is used to derive top-down estimates of CH4 emissions from individual European countries for the year 2001. We employ a model zoom over Europe with 1° × 1° resolution that is two-way nested into the global model domain (with resolution of 6° × 4°. This approach ensures consistent boundary conditions for the zoom domain and thus European top-down estimates consistent with global CH4 observations. The TM5 model, driven by ECMWF analyses, simulates synoptic scale events at most European and global sites fairly well, and the use of high-frequency observations allows exploiting the information content of individual synoptic events. A detailed source attribution is presented for a comprehensive set of 56 monitoring sites, assigning the atmospheric signal to the emissions of individual European countries and larger global regions. The available observational data put significant constraints on emissions from different regions. Within Europe, in particular several Western European countries are well constrained. The inversion results suggest up to 50-90% higher anthropogenic CH4 emissions in 2001 for Germany, France and UK compared to reported UNFCCC values (EEA, 2003. A recent revision of the German inventory, however, resulted in an increase of reported CH4 emissions by 68.5% (EEA, 2004, being now in very good agreement with our top-down estimate. The top-down estimate for Finland is distinctly smaller than the a priori estimate, suggesting much smaller CH4 emissions from Finnish wetlands than derived from the bottom-up inventory. The EU-15 totals are relatively close to UNFCCC values (within 4-30% and appear very robust for different inversion scenarios.

  17. 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.

  18. Reactions of 11C recoil atoms in the systems H2O-NH3, H2O-CH4 and NH3-CH4

    International Nuclear Information System (INIS)

    Nebeling, B.

    1988-11-01

    In this study the chemical reactions of recoil carbon 11 in the binary gas mixtures H 2 O-NH 3 , H 2 O-CH 4 and NH 3 -CH 4 in different mixing ratios as well as in solid H 2 O and in a solid H 2 O-NH 3 mixture were analyzed in dependence of the dose. The analyses were to serve e.g. the simulation of chemical processes caused by solar wind, solar radiation and cosmic radiation in the coma and core of comets. They were to give further information about the role of the most important biogeneous element carbon, i.e. carbon, in the chemical evolution of the solar system. Besides the actual high energy processes resulting in the so-called primary products, also the radiation-chemical changes of the primary products were also observed in a wide range of dosing. The generation of the energetic 11 C atoms took place according to the target composition by the nuclear reactions 14 N(p,α) 11 C, 12 C( 3 He,α) 11 C or the 16 O(p,αpn) 11 C reaction. The identification of the products marked with 11 C was carried out by means of radio gas chromatography or radio liquid chromatography (HPLC). (orig./RB) [de

  19. Osteoporose und Genetik des Knochenstoffwechsels

    Directory of Open Access Journals (Sweden)

    Obermayer-Pietsch B

    2002-01-01

    Full Text Available Osteoporose ist in hohem Maß genetisch determiniert. Neue Wege der molekularbiologischen Forschung haben sich in den letzten Jahren auf diesem Gebiet etabliert. "Gene mapping" mit polymorphen genetischen Markern auf der Suche nach Phänotyp-assoziierten Genen ist ein aufwendiges, aber vielversprechendes Verfahren und wird durch die Erkenntnisse des Human Genome Projects beschleunigt. So wurde jüngst u. a. das Low-density Lipoprotein 5-Gen als wichtig für den Knochenstoffwechsel identifiziert. Kandidaten-gene wie Hormonrezeptor-, Cytokin- oder Kollagen-Gene werden hinsichtlich ihrer Gen-Gen- und Gen-Umwelt- Interaktionen untersucht und erlauben neue funktionelle Einsichten in Erkrankungen des Knochenstoffwechsels. Mutationen der Kollagen-Gene sind bei einigen seltenen Erkrankungen, wie dem Osteoporose-Pseudogliom-Syndrom oder der Osteogenesis imperfecta gefunden worden, könnten aber auch für häufige Varianten von Bindegewebsstörungen wie der congenitalen Hüftdysplasie verantwortlich sein, die etwa 10 % der weiblichen kaukasischen Bevölkerung in unterschiedlichem Ausmaß betrifft. Osteoporose am Schenkelhals und erhöhte Gelenkslaxizität sowie andere generalisierte Veränderungen des Knochen- und Kollagenstoffwechsels können hier möglicherweise ebenfalls durch Störungen des Kollagen I alpha 1-Gens erklärt werden. In Summe können wir zahlreiche neue Einsichten in die Pathophysiologie des Skelettsystems erwarten, die uns auch neue Zugangswege für Diagnostik und Therapie unserer Patienten ermöglichen werden.

  20. Super Rice Cropping Will Enhance Rice Yield and Reduce CH4 Emission: A Case Study in Nanjing, China

    Directory of Open Access Journals (Sweden)

    Yu JIANG

    2013-11-01

    Full Text Available A pot experiment was performed to learn the differences in plant productivity and CH4 emission between two rice cultivars, super rice variety Ningjing 1 and traditional variety Zhendao 11, which were currently commercially applied in Nanjing, China. Similar seasonal changes of CH4 emission fluxes and soil solution CH4 contents were found between the tested cultivars. Although there was no significant difference in plant biomass production between the cultivars, the grain yield of Ningjing 1 was significantly higher by 35.0% (P < 0.05 than that of Zhendao 11, whereas the total CH4 emission from Ningjing 1 was 35.2% lower (P < 0.05. The main difference in the amounts of CH4 emission between the cultivars occurred in the period from the tillering stage to the heading stage. The biomass-scaled and yield-scaled CH4 emissions were respectively 3.8 and 5.2 mg/g for Ningjing 1, significantly lower than those for Zhendao 11 (7.4 and 12.8 mg/g, respectively. According to the relationships between the plant growth characteristics and the CH4 emission, a stronger root system contributed mainly to the lower CH4 emission of Ningjing 1, as compared with Zhendao 11. Our results demonstrated that super rice has advantages not only in grain productivity but also in CH4 emission mitigation. Further expansion of super rice cropping will enhance rice yield and reduce greenhouse gas emission in China.

  1. Transport Mechanisms for CO2-CH4 Exchange and Safe CO2 Storage in Hydrate-Bearing Sandstone

    Directory of Open Access Journals (Sweden)

    Knut Arne Birkedal

    2015-05-01

    Full Text Available CO2 injection in hydrate-bearing sediments induces methane (CH4 production while benefitting from CO2 storage, as demonstrated in both core and field scale studies. CH4 hydrates have been formed repeatedly in partially water saturated Bentheim sandstones. Magnetic Resonance Imaging (MRI and CH4 consumption from pump logs have been used to verify final CH4 hydrate saturation. Gas Chromatography (GC in combination with a Mass Flow Meter was used to quantify CH4 recovery during CO2 injection. The overall aim has been to study the impact of CO2 in fractured and non-fractured samples to determine the performance of CO2-induced CH4 hydrate production. Previous efforts focused on diffusion-driven exchange from a fracture volume. This approach was limited by gas dilution, where free and produced CH4 reduced the CO2 concentration and subsequent driving force for both diffusion and exchange. This limitation was targeted by performing experiments where CO2 was injected continuously into the spacer volume to maintain a high driving force. To evaluate the effect of diffusion length multi-fractured core samples were used, which demonstrated that length was not the dominating effect on core scale. An additional set of experiments is presented on non-fractured samples, where diffusion-limited transportation was assisted by continuous CO2 injection and CH4 displacement. Loss of permeability was addressed through binary gas (N2/CO2 injection, which regained injectivity and sustained CO2-CH4 exchange.

  2. Editorial 01/2013 Normen und Normierungen

    Directory of Open Access Journals (Sweden)

    Christian Swertz

    2013-03-01

    Gottes normativ als wichtigste Instanz der Wahrheit begriffen haben, dem die Schrift untergeordnet war. Er rekapituliert dabei im Rekurs auf Michel Foucaults Ordnung der Dinge das moderne Aufkommen einer schrift- und d. h. am Alphabet orientierten Medientheorie etwa bei Jacques Derrida und Friedrich Kittler und expliziert die sozialdisziplinierende und normierende Rolle der Pädagogik, die bis in die Gegenwart reicht. Diese Normierungen existieren auch, so Friesen, in den aktuellen Debatten zur computeraffinen Generation der Digital Natives für die indes andere (medienkompetente Normen der (Medien-pädagogik gelten als für historische Generationen.Und so untersuchen auch Sascha Trültsch und Daniela Pscheida mit ihrem Beitrag die Frage nach Normen und Normierungen im Blick auf die Geschichte und Gegenwart des privaten Lebens. Dabei zeigen sie in vier Schritten, dass Privatheit etwa in der (publizistischen Fotografie seit jeher eine – auch skandalöse oder verletzende – Rolle gespielt hat und heben hervor, dass es dabei immer um normierende Mediennutzung ging und geht. Der Bereich des Geheimen und seiner Aufklärung wird dabei ebenso analysiert wie der Problembereich der kommunikativen Übertragung(en zwischen Privatem und Öffentlichem. So scheint mit der TV-Sendung Big Brother eine gläserne Durchsichtigkeit und Normierung der Intimität erreicht zu sein, die einen markanten Einschnitt in der Mediengeschichte der „veröffentlichten Privatheit“ darstellt, womit auch eine tiefe Veränderung normativer Konzepte einhergeht. Doch damit nicht genug, halten die AutorInnen anhand breiter empirischer Daten fest, dass wir es heute zwar mit Normverschiebungen und -lockerungen zu tun haben, nicht aber mit einer grundsätzlichen Auflösung von Normen und Normierungen in der Wissens- und Informationsgesellschaft.Hier setzen auch Christian Filk und Fredrik Gundelsweiler an, wenn sie analysieren, wie der seit Jahren anhaltende Technologisierungs- beziehungsweise

  3. Männer und Frauen sind nicht gleich. Über Geschlechterstereotype in juristischen Verfahren Men and Women are not Equal. On Gender Stereotypes in Legal Proceedings

    Directory of Open Access Journals (Sweden)

    Claudia Fröhlich

    2004-07-01

    Full Text Available Weibliche und männliche Angeklagte wurden in den NS-Prozessen nach 1945 nicht gleich behandelt. In den Aufsätzen des von Ulrike Weckel und Edgar Wolfrum herausgegebenen Sammelbandes ‚Bestien‘ und ‚Befehlsempfänger‘. Frauen und Männer in NS-Prozessen nach 1945 werden der unmittelbar nach der Kapitulation Deutschlands von den Alliierten initiierte Nürnberger Prozess gegen die Hauptkriegsverbrecher, die Verfahren gegen SS-Aufseherinnen sowie die Hochverratsprozesse in der Weimarer Republik und im Nationalsozialismus analysiert. Daneben ist die Berichterstattung über den Nürnberger Prozess als einem „medialen Großereignis“ ebenso Gegenstand der Untersuchung wie die Fernsehberichterstattung über das in den 1970er Jahren geführte Majdanek-Verfahren gegen SS-Aufseher und -Aufseherinnen. Die Autorinnen fragen, ob und welche Geschlechterstereotype Rechtsprechung und Berichterstattung geprägt haben, welche Funktionen den dabei formulierten Männer- und Frauenbildern im Kontext der Konstituierung der beiden deutschen Gesellschaften nach 1945 zukamen und wie sie kulturgeschichtlich zu verorten sind. Nach der mittlerweile etablierten Täterinnenforschung rückt ein geschlechtergeschichtlicher Ansatz in das Blickfeld der Forschung zu NS-Prozessen und ihrer Wahrnehmung, der frauen- und männergeschichtliche Studien gleichermaßen anregen kann.Accused men and women were not treated equally in the Nazi trials after 1945. In the articles of the volume edited by Ulrike Weckel und Edgar Wolfrum ‘Bestien’ und ‘Befehlsempfänger’. Frauen und Männer in NS-Prozessen nach 1945, the Nuremberg Trials—initiated by the Allies against the main war criminals immediately after the capitulation of Germany, trials against SS concentration camp guards, and trials of high treason during the Weimar Republic and National Socialism are analyzed. A further subject of the study is the reporting of the Nuremberg Trials as a “major media event”, as

  4. GeNeMe ´98 - Virtuelle Organisation und Neue Medien 1998

    OpenAIRE

    2016-01-01

    Aus dem Vorwort: "Die ausgehenden neunziger Jahre zeigen nach allgemeiner Ansicht vor allem durch die Möglichkeiten des Internet die Auswirkungen der Informationstechnologie auf Wirtschaft und Gesellschaft. Als militärisches Informationsnetzwerk geboren und lange Zeit einer wissenschaftlich arbeitenden Minderheit Vorbehalten, hat sich das „Netz der Netze“ zu einem nahezu ubiquitär verfügbaren Medium entwickelt. Umso erstaunlicher erscheint es, daß die ökonomische Nutzbarkeit dieser Plattfo...

  5. Erkrankungen des Traumaspektrums bei ruandischen Waisen des Genozids : Epidemiologie und Behandlung

    OpenAIRE

    Schaal, Susanne

    2006-01-01

    Im Jahre 1994 kamen in Ruanda innerhalb von 100 Tagen fast eine Million Menschen auf brutalste Weise ums Leben. Vorliegende Studie untersuchte die Traumakonfrontation und mentalen Gesundheitseffekte dieses staatlich organisierten Genozids bei ruandischen Waisen (n = 118) 11 Jahre nach dem Völkermord. Die Stichprobe setzte sich aus Vollwaisen zusammen, die entweder in kindergeführten Haushalten oder in Waisenheimen der Hauptstadt Kigali lebten. Risikofaktoren wurden analysiert und die Wirksamk...

  6. Theorie und Validierung der Modellbildung bipolarer Leistungshalbleiter im Temperaturbereich von 100K bis 400K

    OpenAIRE

    Schlögl, Andreas E.

    2007-01-01

    Theoretische Grundlagen zur temperaturabhängigen Modellbildung bipolarer Leistungshalbleiter wurden untersucht, optimiert und validiert. Basierend auf der neuen Formulierung von Trägerbeweglichkeiten nach Mnatsakanov wurde eine neue Kontinuitätsgleichung zur Beschreibung des bipolaren Stromtransports in schwach dotierten Driftzonen hergeleitet und charakterisiert. Ein vollständiges Leistungsdioden-Modell wurde erstellt. Zur temperaturabhängigen Validierung wurden experimentelle Techniken entw...

  7. Die Tempel von Khajuraho (Indien) und ihre erotischen Skulpturen in den Augen ihrer Betrachter

    OpenAIRE

    Spieß, Nicolai

    2008-01-01

    Ebenso wie der klassische Sanskrittext des Kamasutra des Vatsayana (ca. 3. Jh. nach unserer Zeitrechnung) mit seinen detaillierten Beschreibungen sexueller Praktiken, waren und sind auch die Tempel von Khajuraho aus der Epoche der Chandella Dynstie (10. bis 12. Jh.) mit ihren erotischen Skulpturen (mithunas) Gegenstand zahlloser Beschreibungen und Interpretationen. Stark beeinfusst durch die Kolonialzeit mit ihrer sexualfeindlichen Grundhaltung, ist in Indien, bis in die jüngste Vergangenheit...

  8. Energiesuffizienz - Transformation von Energiebedarf, Versorgungsökonomie, Geschlechterverhältnissen und Suffizienz

    OpenAIRE

    Spitzner, Meike; Buchmüller, Sandra

    2016-01-01

    Effizienzpolitiken allein werden nicht mehr ausreichen, um Klimaschutzziele zu erreichen. Diese Erkenntnis setzt sich in der aktuellen Nachhaltigkeitsdebatte immer mehr durch, partiell selbst innerhalb der Green Economy-Diskurse. Wir werden um Politiken der Eindämmung struktureller Energiebedarfs-Erzeugung nicht herumkommen. Allerdings besteht die Gefahr, dass die Forderungen nach Suffizienz und "Maß-Halten" nicht die Erwerbsökonomie und Wachstumspolitiken adressieren, sondern die privaten Ha...

  9. Airborne measurements of CO2, CH4 and HCN in boreal biomass burning plumes

    Science.gov (United States)

    O'Shea, Sebastian J.; Bauguitte, Stephane; Muller, Jennifer B. A.; Le Breton, Michael; Archibald, Alex; Gallagher, Martin W.; Allen, Grant; Percival, Carl J.

    2013-04-01

    Biomass burning plays an important role in the budgets of a variety of atmospheric trace gases and particles. For example, fires in boreal Russia have been linked with large growths in the global concentrations of trace gases such as CO2, CH4 and CO (Langenfelds et al., 2002; Simpson et al., 2006). High resolution airborne measurements of CO2, CH4 and HCN were made over Eastern Canada onboard the UK Atmospheric Research Aircraft FAAM BAe-146 from 12 July to 4 August 2011. These observations were made as part of the BORTAS project (Quantifying the impact of BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellites). Flights were aimed at transecting and sampling the outflow from the commonly occurring North American boreal forest fires during the summer months and to investigate and identify the chemical composition and evolution of these plumes. CO2 and CH4 dry air mole fractions were determined using an adapted system based on a Fast Greenhouse Gas Analyser (FGGA, Model RMT-200) from Los Gatos Research Inc, which uses the cavity enhanced absorption spectroscopy technique. In-flight calibrations revealed a mean accuracy of 0.57 ppmv and 2.31 ppbv for 1 Hz observations of CO2 and CH4, respectively, during the BORTAS project. During these flights a number of fresh and photochemically-aged plumes were identified using simultaneous HCN measurements. HCN is a distinctive and useful marker for forest fire emissions and it was detected using chemical ionisation mass spectrometry (CIMS). In the freshest plumes, strong relationships were found between CH4, CO2 and other tracers for biomass burning. From this we were able to estimate that 8.5 ± 0.9 g of CH4 and 1512 ± 185 g of CO2 were released into the atmosphere per kg of dry matter burnt. These emission factors are in good agreement with estimates from previous studies and can be used to calculate budgets for the region. However for aged plumes the correlations between CH4 and other

  10. Electromagnetism and life. A field of research bordering on mysticism, medicine and environmental protection; Elektromagnetismus und Leben. Eine Forschungsrichtung zwischen Mystik, Medizin und Umweltschutz

    Energy Technology Data Exchange (ETDEWEB)

    Glaser, R. [Humboldt Univ., Berlin (Germany). Inst. fuer Biologie

    1998-02-01

    The rapid technical development requires scientifically founded answers to people`s fears about hazards of low- and high-frequency magnetic fields. New findings of molecular and cellular biophysics and new methods of detection (fluorescence-optical and electrical) have extended our knowledge about the electrodynamic structure of biological organisms. They promise to provide a scientific foundation both of the limiting values of radiation protection and of new methods in electrotherapy and magnetotherapy. (orig./MG) [Deutsch] Die stuermische Entwicklung der Technik erfordert wissenschaftlich fundierte Antworten auf die Fragen der Bevoelkerung nach moeglichen Gefahren durch elektromagnetische Felder im Nieder- und Hochfrequenzbereich: Erkenntnisse der molekularen und zellulaeren Biophysik und neue fluoreszenzoptische und elektrische Nachweismethoden haben unsere Vorstellung ueber die elektrodynamische Struktur biologischer Organisation wesentlich erweitert und versprechen eine wissenschaftliche Fundierung sowohl der Grenzwerte des Strahlenschutzes als auch neuer Methoden der Elektro- und Magnettherapie. (orig./MG)

  11. Computed tomography of the patellofemoral alignment after arthroscopic reconstruction following patella dislocation; Postoperative Bestimmung des patellofemoralen Alignements nach Patellaluxation - eine computertomographische Analyse

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, R.J.; Hidajat, N.; Maeurer, J.; Felix, R. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-Univ. Berlin (Germany); Weiler, A.; Hoeher, J. [Sektion Sporttraumatologie und Arthroskopie, Klinik fuer Unfall- und Wiederherstellungschirurgie, Charite, Campus Virchow-Klinikum, Humboldt-Univ. Berlin (Germany)

    2003-04-01

    Purpose: To evaluate the diagnostic impact of different CT-based measurements to analyze the patellofemoral alignment after arthroscopic reconstruction in patients with patella dislocation. Materials and Methods: In 18 patients with dislocation of the patella, CT of the patellofemoral joint was performed after arthroscopic reconstruction. Various methods recommended in the literature were used to analyze the structure and the alignment of the patellofemoral joint with a relaxed quadriceps muscle. Axial CT scans were taken in four different knee flexion angles (15 , 30 , 45 , 60 ). Results: After arthroscopic stabilization in patients with patella dislocation, only the lateral patellofemoral angle (15 and 30 knee flexion) and the congruence angle (15 knee flexion) showed significant differences between the CT-measurements in the normal and the operated group. The differences of the remaining mean values were not significant due to a high standard deviation. With increasing flexion of the knee, the differences between the normal and the dislocation group almost disappeared. Only the lateral patellofemoral angle, the patella tilt and the lateral patella shift revealed differences between the normal and the group with recurrent dislocation in every degree of knee flexion. With increasing knee flexion above 30 and especially at 60 , the majority of the measured values returned to the normal range. Conclusions: For CT-measurements of the patellofemoral joint after arthroscopic stabilization, the patellofemoral angle and the congruence angle seemed to be most useful. The measurements of the patellofemoral joint should be taken in various degrees of knee flexion. (orig.) [German] Ziel: Evaluation der Aussagekraft verschiedener CT-Vermessungsmethoden des Patellofemoralgelenkes nach arthroskopischer Stabilisierung bei Patellaluxation. Material und Methode: Axiale CT-Vermessung des Patellofemoralgelenkes bei 18 Patienten nach arthroskopischer medialer patellofemoraler Naht

  12. Erektile Dysfunktion - Was kommt nach Viagra?

    Directory of Open Access Journals (Sweden)

    Jungwirth A

    2001-01-01

    Full Text Available Man darf nie vergessen, daß es sich bei der erektilen Dysfunktion nicht um ein "Life-Style"-Thema, sondern um eine Erkrankung handelt, welche die Lebensqualität der Patienten deutlich verschlechtert. Die Therapie der erektilen Dysfunktion hat sich in den letzten Jahren revolutioniert und wie man sieht, ist sowohl die Forschung als auch die Pharmaindustrie bemüht, für den Patienten neue, bessere, schneller wirksame und nebenwirkungsärmere Medikamente zu entwickeln. Diese neuen Entwicklungen werden für uns Andrologen/Urologen das Armamentarium für die Therapie der erektilen Dysfunktion bereichern. Welche der nun genannten Substanzen letztendlich übrigbleiben und mit welchen Substanzen wir uns in der näheren Zukunft zu befassen haben, werden die weiteren Entwicklungen zeigen.

  13. Direct Measurements of Leaf Level CH4 and CO2 Exchange in a Boreal Forest

    Science.gov (United States)

    Crill, P.; Lindroth, A.; Vestin, P.; Båth, A.

    2008-12-01

    Reports of aerobic CH4 sources from leaves and litter of a variety of forests and plant functional types have added a potential mystery to our understanding of CH4 dynamics especially if these sources contribute enough to have a significant impact on the global budget. We have made direct measurements of leaf level CH4 and CO2 exchange using a quartz branch cuvette in a boreal forest in Norunda, Sweden since August of this year. The cuvette was temperature controlled and was designed to close for 5 minutes every 30 minutes. Air was circulated to a Los Gatos CH4/CO2 infrared absorption laser spectrometer. Air and cuvette temperatures, PAR and UV radiation (Kipp and Zonen, CUV4; spectral range 300-380 nm) were measured at the branch chamber. The study was made in the Norunda 100 years old stand consisting of a mixture of Scots pine (Pinus sylvestris L.) , Birch (Betula sp.) and Norway spruce (Picea abies (L.) Karst.). The cuvette was moved between trees at roughly 5 day intervals. A null empty cuvette period was included in the rotation. The initial data show the expected CO2 uptake correlated with incident PAR and low rates of emission at night. However, there was no clear pattern of emissions detectable in the CH4. We estimate that we should be able to resolve a change of 0.5 ppbv CH4 min- 1 with our analytical setup. Both the daytime (1000-1600) and nighttime (2200-0400) averages were less than our detection. Even on very sunny days with high PAR and UV flux values, no consistent pattern was detectable. The lack of a distinct signal may be due to the fact that the past month has been very rainy, it is late in the growth season at these latitudes and sun angles are increasing quickly. The trees were at the northern edge of a clearing and we were also measuring mid height (2-3 m) leaves and branches of young trees. The branch cuvette design can also be optimized to improve its sensitivity.

  14. CO2 and CH4 exchange by Phragmites australis under different climates

    Science.gov (United States)

    Serrano Ortiz, Penélope; Chojnickic, Bogdan H.; Sánchez-Cañete, Enrique P.; Kowalska, Natalia; López-Ballesteros, Ana; Fernández, Néstor; Urbaniak, Marek; Olejnik, Janusz; Kowalski, Andrew S.

    2015-04-01

    The key role of wetlands regarding global warming is the resulting balance between net CO2 assimilation, via photosynthesis, and CO2 and CH4 emissions, given the potential to release stored carbon, because of the high temperature sensitivity of heterotrophic soil respiration and anoxic conditions. However, it is still unknown whether wetlands will convert from long-term carbon sinks to sources as a result of climate change and other anthropogenic effects such as land use changes. Phragmites australis is one of the most common species found in wetlands and is considered the most globally widespread and productive plant species in this type of ecosystem. In this context, the main objective of this study is to analyse the GHG exchange (CO2 and CH4) of two wetlands with Phragmites australis as the dominant species under different climates using the eddy covariance (EC) technique. The first site, Padul, is located in southern Spain, with a sub-humid warm climate, characterised by a mean annual temperature of 16°C and annual precipitation of ca. 470 mm, with a very dry summer. The second site, Rzecin is located in Poland with a mean annual temperature of 8°C, and annual precipitation around 600mm with no dry season. The Padul EC station is equipped with two infrared gas analysers to measure CO2 and CH4 fluxes (LI-7200 and LI-7700 respectively) while the Rzecin EC station has the same CH4 sensor as Padul, but also a sensor measuring both GHG fluxes (DLT-100 Fast Methane Analyser, Los Gatos). In this study, we present: i) the results of a CH4 analyser inter-comparison campaign (LI-7700 vs. Los Gatos), ii) a comparative analysis of the functional behaviour of respiration and photosynthesis in both sites testing relationships between CO2 fluxes measured with the EC technique and meteorological variables such as temperature and direct or diffuse radiation and iii) the CH4 dynamicsat both sites by identifying, when possible, annual, seasonal and diurnal patterns.

  15. Annual variation of CH4 emissions from the middle taiga in West Siberian Lowland (2005–2009: a case of high CH4 flux and precipitation rate in the summer of 2007

    Directory of Open Access Journals (Sweden)

    M. Sasakawa

    2012-03-01

    Full Text Available We described continuous measurements of CH4 and CO2 concentration obtained at two sites placed in the middle taiga, Karasevoe (KRS and Demyanskoe (DEM, in West Siberian Lowland (WSL from 2005 to 2009. Although both CH4 and CO2 accumulation (ΔCH4 and ▵CO2 during night-time at KRS in June and July 2007 showed an anomalously high concentration, higher ratios of ΔCH4/ΔCO2 compared with those in other years indicated that a considerably higher CH4 flux occurred relative to the CO2 flux. The daily CH4 flux calculated with the ratio of ΔCH4/ΔCO2 and terrestrial biosphere CO2 flux from an ecosystem model showed a maximum in July at the both sites. Although anomalously high flux was observed in June and July 2007 at KRS, only a small flux variation was observed at DEM. The high regional CH4 flux in June and July 2007 at KRS was reproduced using a process-based ecosystem model, Vegetation Integrative Simulator for Trace gases (VISIT, in response to high water table depth caused by the anomalously high precipitation during the summer of 2007.

  16. Comparison of atmospheric CH4 concentration observed by GOSAT and in-situ measurements in Thailand and India

    Science.gov (United States)

    Hayashida, S.; Ono, A.; Ishikawa, S.; Terao, Y.; Takeuchi, W.

    2012-12-01

    The concentration of atmospheric methane (CH4) has more than doubled since pre-industrial levels and the observed long-term changes in the CH4 concentration have been attributed to anthropogenic activity. However, despite the importance of atmospheric CH4 in global warming, the strength of individual sources of CH4 remains highly uncertain [e.g.,Dlugokencky et al., 2011]. To characterize and quantify the emissions of CH4 especially in Monsoon Asia and Siberia, which are the most important regions as CH4 source, we started a new project, "Characterization and Quantification of global methane emissions by utilizing GOSAT and in-situ measurements " by support of the Environment Research and Technology Development Fund (ERTDF) from June 2012 under the umbrella of Ministry of Environment Japan. The projects includes (1) satellite data applications, (2) in-situ measurements in Siberia, over Western Pacific and in Monsoon Asia, (3) development of the inverse model to derive CH4 emissions by top-down approach, and (4) flux measurements in Siberia and Asia to improve the bottom-up inventories. As an initiatory approach in the project, we started air sampling in Thailand and India where there are only a few CH4 data of direct sampling with high precision. We took eight air samples at Kohn Kaen and Pimai in Thailand on June 9 and 10, 2012. The high CH4 concentration near rice paddy field contrasted to the lower CH4 concentration near Cassava field. We are planning to take more samples in India in mid-August. The satellite CH4 data including GOSAT and SCIAMACHY are also compared with the Land Surface Water Coverage (LSWC) and the Normalized Difference Vegetation Index (NDVI). The analysis revealed the seasonal variation in of xCH4 is closely related to the variation of the LSWC, coupled with NDVI. However, the satellite measurements are all column-averaged mixing ratio (xCH4), and therefore do not necessarily reflect high CH4 concentration near the surface over the emission

  17. Das Répertoire International des Sources Musicales (RISM nach Fünfzig Jahren

    Directory of Open Access Journals (Sweden)

    Heckmann, Harald

    2001-12-01

    Full Text Available In 1952, a Commission Mixte formed by members of the International Musicological Society (IMS and the International Association of Music Libraries (lAML constituted in Paris the Répertoire International des Sources Musicales (RISM. In 1971, the first two volumes appeared - the Écrits imprimés concernant la musique edited by François Lesure. In 1960, a central editorial office (Zentralredaktion was founded in Kassel for the Series of the Einzeldrucke vor 1800/Single Prints before 1800. Consisting of 13 volumes, this is now complete with the exception of an index. Since moving to Frankfurt am Main in 1987, the Zentralredaktion has concentrated its work on the Handschriften nach 1600/Manuscripts after 1600. Because of its scope, this project presented RISM with an enormous challenge and, therefore, digitalization was a very early priority. In 1995, the first CD-ROM with the RISM manuscript database appeared followed each year by a cumulative edition; the sixth CD appeared at the end of 2000 containing about 350,000 entries from 575 libraries in 31 countries. Looking at what has been achieved in the last 50 years and taking into account the Series of special catalogs, now expanded to 29 printed volumes, the result deserves respect. There are, however, gaps. These include the fact that in some countries with an especially rich tradition, sources not yet accessible will have to be integrated into the RISM catalog. Spain is such a country and F. Gonzalez Valle has rendered great service in making these sources accessible. His pupils and successors are called upon to mobilize all forces so that within the international RISM community Spain takes up the place appropriate to its past and present rich musical culture.[de] 1952 konstituierte eine Commission Mixte aus Mitgliedern der Internationalen Gesellschaft fur Musikwissenschaft (IGMW und der Internationalen Vereinigung der Musikbibliotheken (IVMB in Paris das Répertoire International des Sources

  18. Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence

    International Nuclear Information System (INIS)

    Johnston, Carmel E; Ewing, Stephanie A; Harden, Jennifer W; Fuller, Christopher C; Manies, Kristen; Varner, Ruth K; Wickland, Kimberly P; Koch, Joshua C; Jorgenson, M Torre

    2014-01-01

    Permafrost soils store over half of global soil carbon (C), and northern frozen peatlands store about 10% of global permafrost C. With thaw, inundation of high latitude lowland peatlands typically increases the surface-atmosphere flux of methane (CH 4 ), a potent greenhouse gas. To examine the effects of lowland permafrost thaw over millennial timescales, we measured carbon dioxide (CO 2 ) and CH 4 exchange along sites that constitute a ∼1000 yr thaw chronosequence of thermokarst collapse bogs and adjacent fen locations at Innoko Flats Wildlife Refuge in western Alaska. Peak CH 4 exchange in July (123 ± 71 mg CH 4 –C m −2 d −1 ) was observed in features that have been thawed for 30 to 70 (<100) yr, where soils were warmer than at more recently thawed sites (14 to 21 yr; emitting 1.37 ± 0.67 mg CH 4 –C m −2 d −1 in July) and had shallower water tables than at older sites (200 to 1400 yr; emitting 6.55 ± 2.23 mg CH 4 –C m −2 d −1 in July). Carbon lost via CH 4 efflux during the growing season at these intermediate age sites was 8% of uptake by net ecosystem exchange. Our results provide evidence that CH 4 emissions following lowland permafrost thaw are enhanced over decadal time scales, but limited over millennia. Over larger spatial scales, adjacent fen systems may contribute sustained CH 4 emission, CO 2 uptake, and DOC export. We argue that over timescales of decades to centuries, thaw features in high-latitude lowland peatlands, particularly those developed on poorly drained mineral substrates, are a key locus of elevated CH 4 emission to the atmosphere that must be considered for a complete understanding of high latitude CH 4 dynamics. (paper)

  19. Rotational study of the CH4–CO complex: Millimeter-wave measurements and ab initio calculations

    International Nuclear Information System (INIS)

    Surin, L. A.; Tarabukin, I. V.; Panfilov, V. A.; Schlemmer, S.; Kalugina, Y. N.; Faure, A.; Rist, C.; Avoird, A. van der

    2015-01-01

    The rotational spectrum of the van der Waals complex CH 4 –CO has been measured with the intracavity OROTRON jet spectrometer in the frequency range of 110–145 GHz. Newly observed and assigned transitions belong to the K = 2–1 subband correlating with the rotationless j CH4 = 0 ground state and the K = 2–1 and K = 0–1 subbands correlating with the j CH4 = 2 excited state of free methane. The (approximate) quantum number K is the projection of the total angular momentum J on the intermolecular axis. The new data were analyzed together with the known millimeter-wave and microwave transitions in order to determine the molecular parameters of the CH 4 –CO complex. Accompanying ab initio calculations of the intermolecular potential energy surface (PES) of CH 4 –CO have been carried out at the explicitly correlated coupled cluster level of theory with single, double, and perturbative triple excitations [CCSD(T)-F12a] and an augmented correlation-consistent triple zeta (aVTZ) basis set. The global minimum of the five-dimensional PES corresponds to an approximately T-shaped structure with the CH 4 face closest to the CO subunit and binding energy D e = 177.82 cm −1 . The bound rovibrational levels of the CH 4 –CO complex were calculated for total angular momentum J = 0–6 on this intermolecular potential surface and compared with the experimental results. The calculated dissociation energies D 0 are 91.32, 94.46, and 104.21 cm −1 for A (j CH4 = 0), F (j CH4 = 1), and E (j CH4 = 2) nuclear spin modifications of CH 4 –CO, respectively

  20. Factors affecting variation in CH4 emission from paddy soils grown with different rice cultivars: A pot experiment

    Science.gov (United States)

    Watanabe, Akira; Kimura, Makoto

    1998-08-01

    The growth of rice plants greatly influences CH4 emission from paddy fields through the supply of organic materials such as root exudates and sloughed tissues, the release of oxygen to the root environment, and the transfer of CH4 from the rhizosphere into the atmosphere through the aerenchyma. In the present pot experiments, the effects of the release of water-soluble organic substances from roots, the air space in roots, and the CH4-oxidizing capacity of roots on intervarietal differences in CH4 emission were examined using three Japonica type cultivars (Norin 25, Nipponbare, and Aoinokaze), which differ in morphological properties. The CH4 emission rates varied among the cultivars from mid-July (tillering stage) to the beginning of September (heading stage).Total CH4 emission throughout the rice growth period was largest for Norin 25, followed by Nipponbare, and Aoinokaze. In August, the rate of release of water-soluble organic substances from roots was largest for Norin 25. The air space in roots was also largest in Norin 25 and least in Aoinokaze. The stable carbon isotopic ratios (δ13C) of CH4 in roots were 3-10‰ higher than those in soil in August. The difference in δ13C values of CH4 between roots and soil was largest for Aoinokaze and smallest for Norin 25. In September, the difference in δ13C values of CH4 between roots and soil became small (2-3‰). These findings suggest that the proportion of CH4 oxidation in the rhizosphere was largest in the cultivar which emitted the smallest amount of CH4 and that the proportion became smaller with continued plant growth.

  1. Quantifying 12/13CH4 migration and fate following sub-surface release to an agricultural soil

    International Nuclear Information System (INIS)

    Shaw, G.; Atkinson, B.; Meredith, W.; Snape, C.; Steven, M.; Hoch, A.; Lever, D.

    2014-01-01

    Following gas generation in a Geological Disposal Facility (GDF), 14 C-containing gases could migrate through the geosphere, eventually diffusing into soils at the Earth's surface. This paper reports summary results from laboratory and field experiments to obtain information on the probable rates of a) diffusive transport and b) oxidation of 12/13 CH 4 (as a surrogate for 14 CH 4) in a typical agricultural soil in the UK. Rates of CH 4 oxidation were generally low in the field and undisturbed soil columns, though a re-packed column of homogenised topsoil oxidised ambient atmospheric CH 4 20× faster than an undisturbed soil column. In contrast to low observed rates of CH 4 oxidation, the effective diffusion of CH 4 through the soil was rapid. Isotopically labelled CH 4 injected at a depth of 45 cm in the field diffused to the surface and exited the soil over a time period ranging from 8 to 24 h. The rate of CH 4 diffusion through the soil was increased by the presence of ryegrass roots which increased soil porosity and decreased water content. δ 13 C values for laboratory column soils after labelled CH 4 injection experiments showed no sign of residual 13 C, despite the extremely high δ 13 C values of the injected 12/13 CH 4 . If laboratory observations are confirmed by measurements in field samples it can be concluded that the majority of 14 CH 4 from a GDF which enters a soil with low methanotrophic activity will be lost to the free atmosphere after diffusing rapidly through the soil column

  2. Simulations and experimental investigations of the competitive adsorption of CH4 and CO2 on low-rank coal vitrinite.

    Science.gov (United States)

    Yu, Song; Bo, Jiang; Jiahong, Li

    2017-09-16

    The mechanism for the competitive adsorption of CH 4 and CO 2 on coal vitrinite (DV-8, maximum vitrinite reflectance R o,max  = 0.58%) was revealed through simulation and experimental methods. A saturated state was reached after absorbing 17 CH 4 or 22 CO 2 molecules per DV-8 molecule. The functional groups (FGs) on the surface of the vitrinite can be ranked in order of decreasing CH 4 and CO 2 adsorption ability as follows: [-CH 3 ] > [-C=O] > [-C-O-C-] > [-COOH] and [-C-O-C-] > [-C=O] > [-CH 3 ] > [-COOH]. CH 4 and CO 2 distributed as aggregations and they were both adsorbed at the same sites on vitrinite, indicating that CO 2 can replace CH 4 by occupying the main adsorption sites for CH 4 -vitrinite. High temperatures are not conducive to the adsorption of CH 4 and CO 2 on vitrinite. According to the results of density functional theory (DFT) and grand canonical Monte Carlo (GCMC) calculations, vitrinite has a higher adsorption capacity for CO 2 than for CH 4 , regardless of whether a single-component or binary adsorbate is considered. The equivalent adsorption heat (EAH) of CO 2 -vitrinite (23.02-23.17) is higher than that of CH 4 -vitrinite (9.04-9.40 kJ/mol). The EAH of CO 2 -vitrinite decreases more rapidly with increasing temperature than the EAH of CH 4 -vitrinite does, indicating in turn that the CO 2 -vitrinite bond weakens more quickly with increasing temperature than the CH 4 -vitrinite bond does. Simulation data were found to be in good accord with the corresponding experimental results.

  3. Laudatio für Herrn Dr. Lars Krogmann : anlässlich der Verleihung des Förderpreises der Ingrid Weiss / Horst Wiehe Stiftung durch der Deutschen Gesellschaft für allgemeine und angewandte Entomologie am 27. Februar 2007 in Innsbruck

    OpenAIRE

    Peters, Ralph

    2008-01-01

    Lars Krogmann wurde 1976 geboren in Norderstedt bei Hamburg. Schon früh entwickelte er eine Leidenschaft für Insekten, insbesondere für Tagschmetterlinge. Der Legende nach soll er bereits als Heranwachsender stets „Entomologe“ als Berufsziel ausgegeben haben. Folgerichtig begann er nach dem Abitur und Zivildienst im Jahr 1996 ein Studium der Biologie in Hamburg. Im Studium belegte er jeden Kurs, der entomologische Inhalte hatte, und er arbeitete als studentische Hilfskraft in der Entomologisc...

  4. Ein Integraler Gestalt-Ansatz fuer Therapie und Beratung

    Directory of Open Access Journals (Sweden)

    Martina Gremmler-Fuhr

    2005-06-01

    Full Text Available Zusammenfassung: In diesem Text stellen wir unseren Ansatz für Psychotherapie und Beratung auf dem Hintergrund des integralen Paradigmas dar. Wir erläutern zunächst kurz vier Anforderungen an ein integrales Konzept in diesem professionellen Bereich: Umgang mit Komplexität und Vielperspektivität, Berücksichtigung gerichteter, vieldimensionaler Entwicklung, Orientierungs- und Sinngebungsfunktion, Realisierung relationaler Qualitäten in der Arbeit. Nach einer Begriffsbestimmung von „Therapie“, „Beratung“ und „Bildung“ charakterisieren wir das seit vielen Jahren von uns entwickelte Konzept für den Integralen Gestalt-Ansatz unter den Fragen nach (1 den Intentionen und Aufgaben von Therapie und Beratung, (2 der Gestaltung der Kommunikation und Beziehung, (3 der Art der Problemdefinition und dem Umgang mit Diagnostik sowie (4 den Strategien und Methoden – alle unter Rückkopplung an die zuvor erläuterten Anforderungen an ein integrales Konzept. Abstract: In this text we present our approach to psychotherapy and counseling on the background of the integral paradigm. We shortly explain four major requirements for such an integral concept: handling complexity and multi-perspectivity, considering directed and multi-dimensional development, offering orientation and meaning, relational qualities. After defining the terms „psychotherapy“, „counselling“, and „education“ we present our concept for the Integral Gestalt Approach which we have developed and evaluated for many years by dealing with four questions: (1 the intentions and tasks of therapy and counselling, (2 the formation of communication and relationship, (3 the specific way of defining problems and using diagnostics, and (4 the strategies and methods – all related back to the major requirements of an integral concept.

  5. Medienbildung und Schulkultur. Implikationen der Verbindung von Medienbildung und Schulkultur für die Medienpädagogik

    Directory of Open Access Journals (Sweden)

    Nina Grünberger

    2017-08-01

    Full Text Available Gegenwärtig werden häufig Fragen nach der Konstituierung der Medienpädagogik als Disziplin gestellt und Antwortversuche aus je unterschiedlicher Perspektive formuliert. Der vorliegende Beitrag unternimmt einen solchen Versuch durch die Diskussion von Implikationen weitreichender Medialisierungsprozesse für die «Disziplinierung» der Medienpädagogik und ihrer Forschungsfelder am Beispiel von Schule als genuin pädagogischem Ort. Die Zusammenführung einer poststrukturalistisch gedachten Medienbildung und einer damit einhergehenden Entdichotomisierung von Subjekt und Welt respektive Subjekt und Medien mit dem Konzept der Schulkultur und einem damit verbundenen holistischen Blick auf das Schulgefüge eröffnet eine neue, produktive und gleichsam kritische Perspektive, ohne dabei jeweils auf eine vereinfachte Gesellschaftskritik zurück zu fallen. Dies stellt bisherige medienpädagogische Theoreme und insbesondere das Medienkompetenzkonzept, das über den medienpädagogischen Wirkungskreis hinaus auch in anderen Kontexten etabliert ist, in Frage. So wird eine neue Perspektive auf Medienpädagogik und ihre Ziele eröffnet, die nicht vorschnell in Abgrenzungsmechanismen unterschiedlicher medienpädagogischer Schulen verfällt, sondern zu aller erst eine «offene» sein will.

  6. Supplement to: Astronomical ephemerides, navigation and war. The astonishing cooperation of the ephemeris institutes of Germany, England, France and the USA during the Second World War based on documents in the archives of the Astronomisches Rechen-Institut. Scans of the documents. (German Title: Supplement zu: Astronomische Ephemeriden, Navigation und Krieg. Die erstaunliche Zusammenarbeit der Ephemeriden-Institute von Deutschland, England, Frankreich und den USA im Zweiten Weltkrieg nach Dokumenten im Archiv des Astronomischen Rechen-Instituts. Scans der Dokumente.)

    Science.gov (United States)

    Wielen, Roland; Wielen, Ute

    In a previous paper (Wielen R. und Wielen U. 2016a: Astronomical Ephemerides, Navigation and War), we have presented the astonishing cooperation of the ephemeris institutes of Germany, England, France and the USA during the Second World War. We were able to use numerous archivalia which we also describe and comment in that paper. In the present paper, we publish colour scans of these archivalia. All the documents shown here are held in the archives of the Astronomisches Rechen-Institut in Heidelberg.

  7. Possibilities for the reduction of CO2- and CH4-emissions of natural gas

    International Nuclear Information System (INIS)

    Muessig, S.

    1994-01-01

    The use of fossil fuels increases the portion of greenhouse gases, especially CO 2 and CH 4 . In this paper firstly the specific emission rates of these greenhouse gases for the various fuels are compared. Secondly possibilities for the reduction of CO 2 and CH 4 for natural gas which are relatively small anyhow are discussed. Thirdly the use of renewable energy within the gas industry and the ocean and into depleted reservoirs are discussed. It is shown that the efficient use of energy of the fossil fuel natural gas is most successful in all branches of gas consumption to decrease emission. Combined-cycle processes, cogeneration as well as modern domestic heating systems are described. Fuel cells and the application of hydrogen is shortly discussed. (orig.)

  8. Thermodynamic calculations in the system CH4-H2O and methane hydrate phase equilibria

    Science.gov (United States)

    Circone, S.; Kirby, S.H.; Stern, L.A.

    2006-01-01

    Using the Gibbs function of reaction, equilibrium pressure, temperature conditions for the formation of methane clathrate hydrate have been calculated from the thermodynamic properties of phases in the system CH4-H 2O. The thermodynamic model accurately reproduces the published phase-equilibria data to within ??2 K of the observed equilibrium boundaries in the range 0.08-117 MPa and 190-307 K. The model also provides an estimate of the third-law entropy of methane hydrate at 273.15 K, 0.1 MPa of 56.2 J mol-1 K-1 for 1/n CH4??H 2O, where n is the hydrate number. Agreement between the calculated and published phase-equilibria data is optimized when the hydrate composition is fixed and independent of the pressure and temperature for the conditions modeled. ?? 2006 American Chemical Society.

  9. Impact of Equivalence Ratio on the Macrostructure of Premixed Swirling CH 4 /Air and CH 4 /O 2 /CO 2 Flames

    KAUST Repository

    Watanabe, Hirotatsu

    2015-06-15

    Premixed CH4/O2/CO2 flames (oxy-flames) and CH4/air flames (air-flames) were experimentally studied in a swirl-stabilized combustor. For comparing oxy and air flames, the same equivalence ratio and adiabatic flame temperature were used. CO2 dilution was adjusted to attain the same adiabatic temperature for the oxy-flame and the corresponding air-flame while keeping the equivalence ratio and Reynolds number (=20,000) the same. For high equivalence ratios, we observed flames stabilized along the inner and outer shear layers of the swirling flow and sudden expansion, respectively, in both flames. However, one notable difference between the two flames appears as the equivalence ratio reaches 0.60. At this point, the outer shear layer flame disappears in the air-flame while it persists in the oxy-flame, despite the lower burning velocity of the oxy-flame. Prior PIV measurements (Ref. 9) showed that the strains along the outer shear layer are higher than along the inner shear layer. Therefore, the extinction strain rates in both flames were calculated using a counter-flow premixed twin flame configuration. Calculations at the equivalence ratio of 0.60 show that the extinction strain rate is higher in the oxy than in the air flame, which help explain why it persists on the outer shear layer with higher strain rate. It is likely that extinction strain rates contribute to the oxy-flame stabilization when air flame extinguish in the outer shear layer. However, the trend reverses at higher equivalence ratio, and the cross point of the extinction strain rate appears at equivalence ratio of 0.64.

  10. In-operando elucidation of bimetallic CoNi nanoparticles during high-temperature CH 4 /CO 2 reaction

    KAUST Repository

    Al-Sabban, Bedour E.; Falivene, Laura; Kozlov, Sergey M.; Aguilar Tapia, Antonio; Ould-Chikh, Samy; Hazemann, Jean-Louis; Cavallo, Luigi; Basset, Jean-Marie; Takanabe, Kazuhiro

    2017-01-01

    Dry reforming of methane (DRM) proceeds via CH4 decomposition to leave surface carbon species, followed by their removal with CO2-derived species. Reactivity tuning for stoichiometric CH4/CO2 reactants was attempted by alloying the non-noble metals

  11. Fluxes of CH4 and N2O in aspen stands grown under ambient and twice-ambient CO2

    DEFF Research Database (Denmark)

    Ambus, P.; Robertson, G.P.

    1999-01-01

    Elevated atmospheric CO2 has the potential to change below-ground nutrient cycling and thereby alter the soil-atmosphere exchange of biogenic trace gases. We measured fluxes of CH4 and N2O in trembling aspen (Populus tremuloides Michx.) stands grown in open-top chambers under ambient and twice......-ambient CO2 concentrations crossed with `high' and low soil-N conditions. Flux measurements with small static chambers indicated net CH4 oxidation in the open-top chambers. Across dates, CH4 oxidation activity was significantly (P CO2 (8.7 mu g CH4-C m(-2) h(-1)) than...... with elevated CO2 (6.5 mu g CH4-C m(-2) h(-1)) in the low N soil. Likewise, across dates and soil N treatments CH4 was oxidized more rapidly (P CO2 (9.5 mu g CH4-C m(-2) h(-1)) than in chambers with elevated CO2 (8.8 mu g CH4-C m(-2) h(-1)). Methane oxidation in soils incubated...

  12. Process for the separation of contaminant or mixture of contaminants from a Ch4-comprising gaseous feed streem

    NARCIS (Netherlands)

    2012-01-01

    The invention provides a process for the separation of a contaminant or mixture of contaminants from a CH4-comprising gaseous feed streem, comprising the subsequent steps of: a) passing a CH4-comprising gaseous feed streem comprising the contaminant or the mixture of contaminants in to and through a

  13. Emissions of CO2 and CH4 from sludge treatment reed beds depend on system management and sludge loading

    DEFF Research Database (Denmark)

    Olsson, Linda; Dam Larsen, Julie; Ye, Siyuan

    2014-01-01

    , the SD had no vegetation and a poor dewatering capacity, which resulted in anaerobic conditions favoring CH4 emission. In contrast, the well-managed STRB had more aerobic conditions in the sludge residue resulting in low CH4 emission rates. We conclude that well-designed and well-managed STRBs have a low...

  14. Precise soil management as a tool to reduce CH4 and N2O emissions from agricultural soils

    NARCIS (Netherlands)

    Mosquera Losada, J.; Hol, J.M.G.; Rappoldt, C.; Dolfing, J.

    2007-01-01

    Soil compaction stimulates the emission of nitrous oxide (N2O) and methane (CH4) from agricultural soils. N2O and CH4 are potent greenhouse gases, with a global warming potential respectively 296 times and 23 times greater than CO2.. Agricultural soils are an important source of N2O. Hence there is

  15. Comprehensive effects of a sedge plant on CH4 and N2O emissions in an estuarine marsh

    Science.gov (United States)

    Li, Yangjie; Wang, Dongqi; Chen, Zhenlou; Hu, Hong

    2018-05-01

    Although there have been numerous studies focusing on plants' roles in methane (CH4) emissions, the influencing mechanism of wetland plants on nitrous oxide (N2O) emissions has rarely been studied. Here, we test whether wetland plants also play an important role in N2O emissions. Gas fluxes were determined using the in situ static flux chamber technique. We also carried out pore-water extractions, sedge removal experiments and tests of N2O transportation. The brackish marsh acted as a net source of both CH4 and N2O. However, sedge plants played the opposite role in CH4 and N2O emissions. The removal of the sedges led to reduced CH4 emissions and increased accumulation of CH4 inside the sediment. Apart from being a conduit for CH4 transport, the sedges made a greater contribution to CH4 oxidation than CH4 production. The sedges exerted inhibitory effects on the release of N2O. The N2O was barely detectable inside the sediment in both vegetated and vegetation-removed plots. The denitrification measurements and nitrogen addition (the addition rates were equal to 0.028, 0.056 and 0.112 g m-2) experiments suggest that denitrification associated with N2O production occurred mainly in the surface sediment layer. The vascular sedge could transport atmospheric N2O downward into the rhizosphere. The rhizospheric sediment, together with the vascular sedge, became an effective sink of atmospheric N2O.

  16. The H2/CH4 ratio during serpentinization cannot reliably identify biological signatures

    OpenAIRE

    Huang, Ruifang; Sun, Weidong; Liu, Jinzhong; Ding, Xing; Peng, Shaobang; Zhan, Wenhuan

    2016-01-01

    Serpentinization potentially contributes to the origin and evolution of life during early history of the Earth. Serpentinization produces molecular hydrogen (H2) that can be utilized by microorganisms to gain metabolic energy. Methane can be formed through reactions between molecular hydrogen and oxidized carbon (e.g., carbon dioxide) or through biotic processes. A simple criterion, the H2/CH4 ratio, has been proposed to differentiate abiotic from biotic methane, with values approximately lar...

  17. BOREAS TGB-1 NSA CH4 and CO2 Chamber Flux Data

    Science.gov (United States)

    Hall, Forrest G. (Editor); Conrad, Sara K. (Editor); Crill, Patrick; Varner, Ruth K.

    2000-01-01

    The BOREAS TGB-1 team made methane (CH4) and carbon dioxide (CO2) dark chamber flux measurements at the NSA-OJP, NSA-OBS, NSA-BP, and NSA-YJP sites from 16-May-1994 through 13-Sep-1994. Gas samples were extracted approximately every 7 days from dark chambers and analyzed at the NSA lab facility. The data are provided in tabular ASCII files.

  18. Neodadjuvante und adjuvante Kurzzeit-Hormontherapie in Kombination mit konformaler HDR-Brachytherapie beim Prostatakarzinom

    Directory of Open Access Journals (Sweden)

    Martin T

    2004-01-01

    Full Text Available Zielsetzung: Auswertung der Behandlungsergebnisse der neoadjuvanten und adjuvanten Kurzzeit-Hormontherapie kombiniert mit konformaler HDR-Brachytherapie und externer Radiotherapie beim Prostatakarzinom. Patienten und Methoden: Von 01/97 bis 09/99 behandelten wir 102 Patienten mit Prostatakarzinomen im Stadium T1–3 N0 M0. Im Stadium T1–2 befanden sich 71, im Stadium T3 31 Patienten. Der mediane prätherapeutische PSA-Wert betrug 15,3 ng/ml. Nach ultraschallgesteuerter transrektaler Implantation von vier Afterloadingnadeln erfolgte die CT-gestützte 3D-Brachytherapie- Planung. Alle Patienten erhielten vier HDR-Implantate mit einer Referenzdosis von 5 Gy oder 7 Gy pro Implantat. Die Zeit zwischen jedem Implantat betrug jeweils 14 Tage. Nach der Brachytherapie folgte die externe Radiotherapie bis 39,6 Gy oder 45,0 Gy. Alle Patienten erhielten eine neoadjuvante und adjuvante Kurzzeit-Hormontherapie, die 2–19 Monate vor der Brachytherapie eingeleitet und 3 Monate nach Abschluß der externen Radiotherapie abgesetzt wurde (mediane Dauer: 9 Monate. Ergebnisse: Die mediane Nachbeobachtungszeit war 2,6 Jahre (range: 2,0–4,1 Jahre. Die biochemische Kontrollrate betrug 82 % nach 3 Jahren. Bei 14/102 Patienten registrierten wir ein biochemisches Rezidiv, bei 5/102 Patienten ein klinisches Rezidiv. Das Gesamtüberleben betrug 90 %, das krankheitsspezifische Überleben 98,0 % nach 3 Jahren. Ein Patient entwickelte eine prostato-urethro-rektale Fistel als späte Grad 4-Toxizität. Akute Grad-3 Toxizitäten traten bei 4 %, späte Grad-3 Toxizitäten bei 5 % der Patienten auf. Schlußfolgerung: Die neoadjuvante und adjuvante Kurzzeit-Hormontherapie kombiniert mit konformaler HDR-Brachytherapie und externer Radiotherapie erweist sich als sichere und wirksame Behandlungsmodalität beim Prostatakarzinom mit minimalen behandlungsbedingten Toxizitäten und einer vielversprechenden biochemischen Kontrollrate nach medianer Nachbeobachtungszeit von 2,6 Jahren.

  19. Präoperative Vorhersge der Rezidivrate des klinisch lokalisierten Prostatakarzinoms nach einer radikalen Prostatektomie

    Directory of Open Access Journals (Sweden)

    Graefen M

    1999-01-01

    Full Text Available Die radikale Prostatektomie scheint die zur Zeit effektivste Therapie des klinisch lokalisierten Prostatakarzinoms zu sein. Dennoch liegt die Rezidivrate bei bis zu 40 % der operierten Patienten. Mit dieser Arbeit wurde anhand präoperativer Befunde ein Algorithmus entwickelt, mit welchem die Prognose des klinisch lokalisierten Prostatakarzinoms bereits vor einer operativen Therapie abgeschätzt werden kann. Hierzu wurden multiple präoperative Befunde, welche bei der Diagnose des Prostatakarzinoms erhoben werden, bezüglich ihres Einflusses auf einen PSA-Progress nach radikaler Prostatektomie geprüft. Dies erfolgte mittels einer univariaten Kaplan-Meier Analyse sowie einer multivariaten Statistik (Cox-Regression und CART-Analyse. Schwerpunkt bildete hierbei die Einbeziehung der Ergebnisse der systematischen Sextanten-Biopsie der Prostata. Alle präoperativen Befunde haben in der univariaten Kaplan-Meier Analyse einen signifikanten Einfluß auf ein PSA-Rezidiv. In der Cox-Regression hatte der Anteil an niedrigdifferenziertem Prostatakarzinom den größten Einfluß auf das Auftreten eines Tumorprogresses, gefolgt von der Anzahl der positiven Stanzen in der Biopsie und dem präoperativen PSA-Wert; alle anderen Parameter hatten keinen unabhängig signifikanten Einfluß auf den Tumorprogress. Mittels der zusätzlich durchgeführten CART Analyse konnten verschiedene Risikogruppen definiert werden, deren Rezidivrisiko bei 3 % für Patienten mit geringem Rezidivrisiko sowie 80 % für solche mit einem hohen Rezidivrisiko 2 Jahre nach der Operation betrug. Der niedrigdifferenzierte Tumoranteil hat somit den größten Einfluß auf die Prognose eines klinisch lokalisierten Prostatakarzinoms. Anhand der präsentierten CART-Analysen wurden einfach anwendbare Entscheidungsbäume entwickelt, mit denen eine Abschätzung des Therapieerfolges des klinisch lokalisierten Prostatakarzinoms bereits vor einer Operation möglich ist.

  20. The relationships between termite mound CH4/CO2 emissions and internal concentration ratios are species specific

    Directory of Open Access Journals (Sweden)

    H. Jamali

    2013-04-01

    Full Text Available We investigated the relative importance of CH4 and CO2 fluxes from soil and termite mounds at four different sites in the tropical savannas of northern Australia near Darwin and assessed different methods to indirectly predict CH4 fluxes based on CO2 fluxes and internal gas concentrations. The annual flux from termite mounds and surrounding soil was dominated by CO2 with large variations among sites. On a carbon dioxide equivalent (CO2-e basis, annual CH4 flux estimates from termite mounds were 5- to 46-fold smaller than the concurrent annual CO2 flux estimates. Differences between annual soil CO2 and soil CH4 (CO2-e fluxes were even greater, soil CO2 fluxes being almost three orders of magnitude greater than soil CH4 (CO2-e fluxes at site. The contribution of CH4 and CO2 emissions from termite mounds to the total CH4 and CO2 emissions from termite mounds and soil in CO2-e was less than 1%. There were significant relationships between mound CH4 flux and mound CO2 flux, enabling the prediction of CH4 flux from measured CO2 flux; however, these relationships were clearly termite species specific. We also observed significant relationships between mound flux and gas concentration inside mound, for both CH4 and CO2, and for all termite species, thereby enabling the prediction of flux from measured mound internal gas concentration. However, these relationships were also termite species specific. Using the relationship between mound internal gas concentration and flux from one species to predict mound fluxes from other termite species (as has been done in the past would result in errors of more than 5-fold for mound CH4 flux and 3-fold for mound CO2 flux. This study highlights that CO2 fluxes from termite mounds are generally more than one order of magnitude greater than CH4 fluxes. There are species-specific relationships between CH4 and CO2 fluxes from a mound, and between the inside mound concentration of a gas and the mound flux emission of the

  1. The relationships between termite mound CH4/CO2 emissions and internal concentration ratios are species specific

    Science.gov (United States)

    Jamali, H.; Livesley, S. J.; Hutley, L. B.; Fest, B.; Arndt, S. K.

    2013-04-01

    We investigated the relative importance of CH4 and CO2 fluxes from soil and termite mounds at four different sites in the tropical savannas of northern Australia near Darwin and assessed different methods to indirectly predict CH4 fluxes based on CO2 fluxes and internal gas concentrations. The annual flux from termite mounds and surrounding soil was dominated by CO2 with large variations among sites. On a carbon dioxide equivalent (CO2-e) basis, annual CH4 flux estimates from termite mounds were 5- to 46-fold smaller than the concurrent annual CO2 flux estimates. Differences between annual soil CO2 and soil CH4 (CO2-e) fluxes were even greater, soil CO2 fluxes being almost three orders of magnitude greater than soil CH4 (CO2-e) fluxes at site. The contribution of CH4 and CO2 emissions from termite mounds to the total CH4 and CO2 emissions from termite mounds and soil in CO2-e was less than 1%. There were significant relationships between mound CH4 flux and mound CO2 flux, enabling the prediction of CH4 flux from measured CO2 flux; however, these relationships were clearly termite species specific. We also observed significant relationships between mound flux and gas concentration inside mound, for both CH4 and CO2, and for all termite species, thereby enabling the prediction of flux from measured mound internal gas concentration. However, these relationships were also termite species specific. Using the relationship between mound internal gas concentration and flux from one species to predict mound fluxes from other termite species (as has been done in the past) would result in errors of more than 5-fold for mound CH4 flux and 3-fold for mound CO2 flux. This study highlights that CO2 fluxes from termite mounds are generally more than one order of magnitude greater than CH4 fluxes. There are species-specific relationships between CH4 and CO2 fluxes from a mound, and between the inside mound concentration of a gas and the mound flux emission of the same gas, but

  2. Bioelectrochemical methane (CH4) production in anaerobic digestion at different supplemental voltages.

    Science.gov (United States)

    Choi, Kwang-Soon; Kondaveeti, Sanath; Min, Booki

    2017-12-01

    Microbial electrolysis cells (MECs) at various cell voltages (0.5, 0.7 1.0 and 1.5V) were operated in anaerobic fermentation. During the start-up period, the cathode potential decreased from -0.63 to -1.01V, and CH 4 generation increased from 168 to 199ml. At an applied voltage of 1.0V, the highest methane yields of 408.3ml CH 4 /g COD glucose was obtained, which was 30.3% higher than in the control tests (313.4ml CH 4 /g COD glucose). The average current of 5.1mA was generated at 1.0V at which the maximum methane yield was obtained. The other average currents were 1.42, 3.02, 0.53mA at 0.5, 0.7, and 1.5V, respectively. Cyclic voltammetry and EIS analysis revealed that enhanced reduction currents were present at all cell voltages with biocatalyzed cathode electrodes (no reduction without biofilm), and the highest value was obtained with 1V external voltage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Catalytic reduction of NOx with H2/CO/CH4 over PdMOR catalysts

    International Nuclear Information System (INIS)

    Pieterse, Johannis A.Z.; Booneveld, Saskia

    2007-01-01

    Conversion of NO x with reducing agents H 2 , CO and CH 4 , with and without O 2 , H 2 O, and CO 2 were studied with catalysts based on MOR zeolite loaded with palladium and cerium. The catalysts reached high NO x to N 2 conversion with H 2 and CO (>90% conversion and N 2 selectivity) range under lean conditions. The formation of N 2 O is absent in the presence of both H 2 and CO together with oxygen in the feed, which will be the case in lean engine exhaust. PdMOR shows synergic co-operation between H 2 and CO at 450-500 K. The positive effect of cerium is significant in the case of H 2 and CH 4 reducing agent but is less obvious with H 2 /CO mixture and under lean conditions. Cerium lowers the reducibility of Pd species in the zeolite micropores. The catalysts showed excellent stability at temperatures up to 673 K in a feed with 2500 ppm CH 4 , 500 ppm NO, 5% O 2 , 10% H 2 O (0-1% H 2 ), N 2 balance but deactivation is noticed at higher temperatures. Combining results of the present study with those of previous studies it shows that the PdMOR-based catalysts are good catalysts for NO x reduction with H 2 , CO, hydrocarbons, alcohols and aldehydes under lean conditions at temperatures up to 673 K. (author)

  4. Modified ZIF-8 mixed matrix membrane for CO2/CH4 separation

    Science.gov (United States)

    Nordin, Nik Abdul Hadi Md; Ismail, Ahmad Fauzi; Misdan, Nurasyikin; Nazri, Noor Aina Mohd

    2017-10-01

    Tunability of metal-organic frameworks (MOFs) properties enables them to be tailored for specific applications. In this study, zeolitic imidazole framework 8 (ZIF-8), sub-class of MOF, underwent pre-synthesis and post-synthesis modifications. The pre-synthesis modification using GO (ZIF-8/GO) shows slight decrease in textural properties, while the post-synthesis modification using amine solution (ZIF-8/NH2) resulted in superior BET surface area and pore volume. Mixed matrix membranes (MMMs) derived from polysulfone (PSf) and the modified ZIF-8s were then prepared via dry/wet phase inversion. The polymer chain flexibility of the resulted MMMs shows rigidification, where ZIF-8/NH2 as filler resulting higher rigidification compared to ZIF-8/GO. The MMMs were further subjected to pure CO2 and CH4 gas permeation experiments. The PSf/ZIF-8/NH2 shows superior CO2/CH4 selectivity (88% increased) while sacrificing CO2 permeance due to combination of severe polymer chain rigidification and the presence of CO2-philic group, amine. Whereas, the PSf/ZIF-8/GO possess 64% increase in CO2 permeance without notable changes in CO2/CH4 selectivity.

  5. Wastes Management Can Minimize CH4 and N2O Emissions from Wetlands in Indonesia

    Directory of Open Access Journals (Sweden)

    Abdul Hadi

    2015-07-01

    Full Text Available Paddy (Oriza sativa L. and Oil palm (Elaeis guineensis Jack are two important crops and are potential to produce wastes which may lead to huge greenhouse gas emissions if they are not managed properly.  Open burning and conventional composting are commonly practiced by farmers and/or planters to managed agricultural wastes in Indonesia.  A series of research has been carried out  to elucidate (1 the reductions of CH4 and N2O due to incertion of a catalitic converter on burning kiln, (2 the best composting technique of oil palm field wastes, and (3 the effects of oil palm field wastes compost application in oil palm fields and of paddy field wastes biochar in integrated oil palm-paddy fields.  The results showed that CH4 and N2O emissions from paddy field wastes (i.e., rice straw or rice husk was lower than that from oil palm empty fruit bunch (EFB.  Furthermore, insertion of a catalytic converter into pyrolysis installation reduced the CO2, CH4 and N2O emissions from paddy field wastes as much as 14.5, 17.8 and 11.1%, respectively.  Incorporation of EFB compost did not increase greenhouse gas emission from oil palm fields. These results suggest that biochar and EFB compost can be practiced to manage agricultural wastes in Indonesia.

  6. Synthesis of Fine Mo2C Powder from Prereduced Mo in Undiluted CH4 Flow

    Science.gov (United States)

    Cetinkaya, S.; Eroglu, S.

    2017-10-01

    The carburization behavior of prereduced Mo was investigated in undiluted CH4 flow at 900-1000 K. Prior to the experiments, equilibrium thermodynamic analysis was carried out in the Mo-C-H system. The products were characterized by mass measurement, x-ray diffraction and scanning electron microscopy techniques. A single Mo2C phase was obtained within 45 min, 5 min, and 2.5 min at 900 K, 950 K, and 1000 K, respectively, at CH4 contents higher than the predicted ones. The reasons for this behavior were discussed in terms of CH4 stability, open tube flow, and self-created atmosphere in the powder bed. The fractional conversion-time curves indicated that the carburization kinetics followed a linear rate law. The Mo2C crystallite size (26-37 nm) and platelet thickness (50-100 nm) were found to be smaller than those of the parent Mo phase. These findings were attributable to the defects formed as a result of stresses associated with the reduction and the carburization.

  7. Catalytic performance of activated carbon supported cobalt catalyst for CO2 reforming of CH4.

    Science.gov (United States)

    Zhang, Guojie; Su, Aiting; Du, Yannian; Qu, Jiangwen; Xu, Ying

    2014-11-01

    Syngas production by CO2 reforming of CH4 in a fixed bed reactor was investigated over a series of activated carbon (AC) supported Co catalysts as a function of Co loading (between 15 and 30wt.%) and calcination temperature (Tc=300, 400 or 500°C). The catalytic performance was assessed through CH4 and CO2 conversions and long-term stability. XRD and SEM were used to characterize the catalysts. It was found that the stability of Co/AC catalysts was strongly dependent on the Co loading and calcination temperature. For the loadings (25wt.% for Tc=300°C), stable activities have been achieved. The loading of excess Co (>wt.% 25) causes negative effects not only on the performance of the catalysts but also on the support surface properties. In addition, the experiment showed that ultrasound can enhance and promote dispersion of the active metal on the carrier, thus improving the catalytic performance of the catalyst. The catalyst activity can be long-term stably maintained, and no obvious deactivation has been observed in the first 2700min. After analyzing the characteristics, a reaction mechanism for CO2 reforming of CH4 over Co/AC catalyst was proposed. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Oktaedrische vakuoläre Proteinkristalle in Phycomyces blakesleeanus: Biochemische und fluoreszenzspektroskopische Charakterisierung

    OpenAIRE

    Fries, Volker

    2004-01-01

    Die negativ gravitropen Sporangiophoren des Zygomyceten Phycomyces blakesleeanus enthalten in ihrem zentralen Vakuolensystem parakristalline Proteinkörper. Diese sogenannten oktaedrischen Kristalle sedimentieren und zeigen eine passive Verlagerung nach Reorientierung der Sporangiophore im Raum. Aufgrund dessen wird ihre Funktion als Statolithen zur Graviperzeption diskutiert. Die Dichte der Kristalle variiert zwischen von ...

  9. Verzeichnis der Echiuridae, Sipunculidae und Priapulidae des Naturhistorichen Reichsmuseums in Leiden

    NARCIS (Netherlands)

    Stiasny, G.

    1930-01-01

    Die vorliegende Mitteilung ist das Ergebnis der Bearbeitung zumeist älteren Materiales an Echiuriden, Sipunculiden und Priapuliden des Naturhistorischen Reichs-Museums in Leiden. Obwohl die Sammlung nach Anzahl der Exemplare nicht umfangreich ist, zeigt sie einen überraschenden Reichtum an Formen

  10. EMISSION ASSESSMENT AT THE ŠTĚPÁNOVICE MUNICIPAL SOLID WASTE LANDFILL FOCUSING ON CH4 EMISSIONS

    Directory of Open Access Journals (Sweden)

    Dana Adamcová

    2016-07-01

    Full Text Available The study was conducted to measure the emission from landfill in the years 2005–2011. The results are used to diagnose the emissions of CH4. The mean value of CH4 in vol. % in the collection wells ranged from 0 to 2.14 vol. % the mean concentration of CH4 in mg/m3 ranged from 0 to 25 251 mg/m3 the average concentration of CH4 in mg/Nm3 at the measuring and control points ranged from 2.2 to 24.1 mg/Nm3. CH4 emissions from the landfill do not exceed the reporting thresholds the landfill does not meet conditions for being included in the Integrated Register of Pollutants.

  11. CO2 and CH4 fluxes in a Spartina salt marsh and brackish Phragmites marsh in Massachusetts

    Science.gov (United States)

    Tang, J.; Wang, F.; Kroeger, K. D.; Gonneea, M. E.

    2017-12-01

    Coastal salt marshes play an important role in global and regional carbon cycling. Tidally restricted marshes reduce salinity and provide a habitat suitable for Phragmites invasion. We measured greenhouse gas (GHG) emissions (CO2 and CH4) continuously with the eddy covariance method and biweekly with the static chamber method in a Spartina salt marsh and a Phragmites marsh on Cape Cod, Massachusetts, USA. We did not find significant difference in CO2 fluxes between the two sites, but the CH4 fluxes were much higher in the Phragmites site than the Spartina marsh. Temporally, tidal cycles influence the CO2 and CH4 fluxes in both sites. We found that the salt marsh was a significant carbon sink when CO2 and CH4 fluxes were combined. Restoring tidally restricted marshes will significantly reduce CH4 emissions and provide a strong ecosystem carbon service.

  12. "America first": die Außen- und Sicherheitspolitik der USA unter Präsident Trump

    OpenAIRE

    2017-01-01

    "Donald J. Trump ist der 45. Präsident der Vereinigten Staaten - und auch zehn Wochen nach der Wahl hat sich die Aufregung über das Wahlergebnis nicht gelegt. Diesseits des Atlantiks interessiert vor allem eine Frage: Wie wird die amerikanische Außen- und Sicherheitspolitik unter Präsident Trump aussehen? Wird sie von Kontinuität geprägt sein? Oder wird es gravierende Brüche geben? In diesem Report werfen HSFK-Autorinnen und -Autoren Blicke auf Themen, die aus Sicht der Friedens- und Konflikt...

  13. Numerical Simulation and Industrial Experimental Research on the Coherent Jet with "CH4 + N2" Mixed Fuel Gas

    Science.gov (United States)

    Hu, Shaoyan; Zhu, Rong; Dong, Kai; Liu, Runzao

    2018-06-01

    Coherent jet technology is widely used in the electric arc furnace (EAF) steelmaking process to deliver more energy and momentum into the molten steel bath. Meanwhile, the characteristics of a coherent jet using pure CH4 as the fuel gas have been well investigated in previous studies. To reduce the consumption of CH4, coherent jet technology using "CH4 + N2" mixed fuel gas instead of pure CH4 was proposed and studied in detail by numerical simulation in the present work. The Eddy Dissipation Concept model, which has detailed chemical kinetic mechanisms, was adopted to model the fuel gas combustion reactions. Experimental measurements were carried out to validate the accuracy of the computational model. The present study shows that the jet characteristics of the main oxygen improve along with the increase of the CH4 ratio in fuel gas and with the increase of the flow rate of fuel gas. When the CH4 ratio in the fuel gas is 25 pct, the fuel gas flow rate only has a limited influence on the jet characteristics, unlike the rest of the fuel gas compositions, because a high N2 proportion deteriorates the combustion performance and leads to severe incomplete combustion. Moreover, a false potential core phenomenon was observed and explained in the present study. Based on the average values, the jet length of a coherent jet with 75 pct CH4 can achieve 89.8 pct of that with 100 pct CH4. Finally, an industrial experiment was carried out on a commercial 100t EAF using coherent jet with 75 pct CH4, showing that the average CH4 consumption was reduced from 3.84 to 3.05 Nm3 t-1 under the premise of no obvious changes in the other production indexes.

  14. Die Verschränkung von Arbeitskultur, beruflichem Erfolg und Geschlecht in technik- und naturwissenschaftlichen Berufen

    Directory of Open Access Journals (Sweden)

    Inken Lind

    2007-11-01

    Full Text Available In dem Band geht die Autorin Dr. Yvonne Haffner, Wissenschaftliche Mitarbeiterin am Institut für Soziologie der Universität Darmstadt, den strukturellen Barrieren für eine gleichberechtigte Karriere von Frauen und Männern im Beruf nach. Dabei werden vor allem gängige Leistungskriterien in den Blick genommen und die verbreitete Vorstellung von der auf individuellen Leistungen beruhenden Karriere hinterfragt. Die Ergebnisse verdeutlichen, dass karriererelevante Anforderungen nur in relativ geringem Maße an objektivierbare Leistungskriterien gebunden sind und impliziten, wenig objektivierbaren Kriterien eine besondere Bedeutung für den Karriereverlauf zukommt. Diese impliziten Kriterien beziehen sich auf die moderne Arbeitskultur mit ihrem hohen Verfügbarkeitsanspruch, der sich wiederum geschlechtsspezifisch unterschiedlich auswirkt.

  15. Medienpädagogik unter der differenztheoretischen Lupe. Eine Identitätssuche zwischen Disziplin und Profession

    Directory of Open Access Journals (Sweden)

    Franziska Linke

    2017-09-01

    Full Text Available Der Beitrag diskutiert die dem Themenheft zugrundeliegende Fragestellung nach der Konstitution der Medienpädagogik aus einer systemtheoretischen Perspektive. Dabei wird im Anschluss an Stichweh (2013 Ansatz der funktionalen Differenzierung ein Untersuchungsrahmen aufgezeigt, der es ermöglicht, die Medienpädagogik sowohl aus wissenschaftssoziologischer als auch professionssoziologischer Perspektive zu betrachten. Gerade die zentrale Rolle der (digitalen Medien für Lern- und Bildungsprozesse sowie für den Arbeitsmarkt (u. a. KMK 2016 verlangt eine stetige Reflexion professioneller Handlungssysteme der Medienpädagogik, die nicht losgelöst von der Frage nach dem Selbstverständnis der Medienpädagogik als Wissenschaftsdisziplin gelingen kann (u. a. Hugger 2001. Divergierende theoretische Positionierungen der Akteurinnen und Akteure sowie verschiedene Zielvorstellungen zur Medienpädagogik selbst und zu dem, was sie praktisch leisten kann, erschweren ein solches Vorhaben. Die Autorinnen des Beitrags begeben sich daher, unter Berücksichtigung der Differenzierung zwischen Disziplin und Profession, auf die Suche nach möglichen Antworten. Vorgeschlagen wird eine erweiterte Betrachtungsweise, welche die Medienpädagogik als wissenschaftliche Produktionsgemeinschaft beschreibt und dadurch Potenziale eröffnet theoretische und empirische Erkenntnisse von Akteurinnen und Akteuren unterschiedlicher wissenschaftlicher Disziplinen mit Medienzusammenhang zu berücksichtigen. Ferner wird dargelegt, dass ein solcher Beschreibungsansatz neue Forschungsperspektiven auf die professionstheoretische Einordnung praktischer Handlungssysteme der Medienpädagogik eröffnen kann.

  16. Oberbergamt fuer das Saarland und das Land Rheinland-Pfalz, Bergamt Saarbruecken / Bergamt Rheinland-Pfalz. Annual report 1998. Economic and technical aspects, industrial safety and environmental protection, statistics, activities of the mining authorities; Oberbergamt fuer das Saarland und das Land Rheinland-Pfalz, Bergamt Saarbruecken / Bergamt Rheinland-Pfalz. Jahresbericht 1998. Bergwirtschaft, Bergtechnik, Arbeitsschutz, Umweltschutz, Statistiken, Taetigkeiten der Bergbehoerde

    Energy Technology Data Exchange (ETDEWEB)

    Boettcher, R.; Hugo, K.H.; Kuhn, M.; Strauch, T. [comps.

    1999-07-01

    After outlining developmental trends in the various mining sectors as well as the structure and tasks of the State Mines Inspectorate, the annual report describes the activities in the fields of health and industrial safety, mining engineering and safety, and the environmental effects of mining activities, as well as special accidents and incidents. (HS) [German] Nach einem Ueberblick ueber die bergwirtschaftliche Entwicklung in den einzelnen Bergbauzweigen sowie ueber den Aufbau und die Zustaendigkeit der Bergbehoerde werden die Aktivitaeten in den Bereichen Arbeits- und Gesundheitsschutz, Bergtechnik und Sicherheit, Bergbau und Umwelt sowie bemerkenswerte Unfaelle und Vorkommnisse beschrieben. (HS)

  17. CO2 and CH4 fluxes and carbon balance in the atmospheric interaction of boreal peatlands

    International Nuclear Information System (INIS)

    Alm, J.

    1997-01-01

    Release of CO 2 from peat was studied using IR analyzer in a range of boreal peatlands under varying nutrient status and moisture conditions. Root associated CO 2 efflux was separated from the total release by experiments both in the field and in a greenhouse. Emissions of CO 2 and CH 4 (the latter by gas chromatography) were measured during the snow-covered period and their contribution to the annual fluxes of these gases was inspected. Ecosystem exchange of CO 2 under varying irradiation, temperature and moisture conditions was measured at different microsites at two peatland sites with different nutrient ecology. One site represented minerotrophic conditions during a wet growing season and the other site ombrotrophic conditions during an exceptionally dry growing season. Annual carbon balances were compiled for the two sites, and the role of the microsites in the annual carbon balance and CH 4 release was studied. The Holocene history of CO 2 sequestration and CH 4 emission dynamics in a raised mire were simulated using lateral and vertical growth rates derived from radiocarbon ages of peat samples from mire bottom and vertical cores. The model was formulated for a geographic information system (GIS). Artificial or natural lowering of water table increased CO 2 release from peat. A drought lasting from late May to July caused a 90 g C m 2 net loss in the annual C balance of a natural ombrotrophic bog. In drained forested sites the increase in peat CO 2 release could be even 100 %, but the development of the tree layer at least partially compensated for these losses. Wet conditions induced a net accumulation of 67 g C m -2 a -1 in the minerotrophic fen site, while the long term average accumulation rate is estimated to be only 15 g C m -2 a -1 for Finnish fens. Carbon balance in boreal peatlands is thus extremely sensitive to year-to-year climatic variations. Root activity of vascular plants contributed to the total peat CO 2 efflux by 10-40 % as root respiration

  18. [COPD und Klangtherapie: Pilotstudie zur Wirksamkeit einer Behandlung mit Körpertambura bei COPD-Patienten].

    Science.gov (United States)

    Hartwig, Bernhard; Schmidt, Stefan; Hartwig, Isabella

    2016-01-01

    Hintergrund: Erkrankungen der Atemorgane treten mit steigendem Alter öfter auf, nehmen weltweit zu und sind häufige Ursachen für Morbidität und Mortalität. In dieser Pilotstudie wurde der Frage nachgegangen, ob eine einmalige 10-minütige Behandlung mit einer Körpertambura eine signifikante und effektive Verbesserung der Lungenfunktion von Patienten mit chronisch-obstruktiver Lungenerkrankung (COPD; GOLD-Stadium A oder B) erbringen kann. Patienten und Methoden: 54 Probanden konnten je zur Hälfte in eine Behandlungsgruppe (Körpertambura) und eine aktive Kontrollgruppe (Atemtherapie) randomisiert werden. Eine Bestimmung der Lungenfunktionsmessparameter «Einsekundenkapazität» (FEV1) und «inspiratorische Vitalkapazität» (IVC) zu den Zeitpunkten T1 (Baseline), T2 (direkt nach Behandlung) und als Follow-up etwa 3 Wochen nach T1 (T3). Ergebnisse: Die Behandlungsgruppe zeigte sich der Kontrollgruppe in beiden Werten signifikant überlegen. Die Zeit-×-Gruppe-Interaktion (Varianzanalyse) ergab p = 0,001 (FEV1) bzw. p = 0,04 (IVC). Die Behandlungsgruppe zeigte bei beiden Werten eine Verbesserung von klinischer Relevanz. Schlussfolgerung: Diese Ergebnisse zeigen, dass die Klangbehandlung mittels einer Körpertambura - neben den schulmedizinischen, leitliniengerechten Therapien - eine zusätzliche, nebenwirkungsarme, aber durchaus klinisch wirksame Option für die Behandlung von COPD-Patienten darstellen kann, um deren Lebensqualität zu stabilisieren und zu verbessern. © 2016 S. Karger GmbH, Freiburg.

  19. Effect of CH4 concentration on the growth behavior, structure, and transparent properties of ultrananocrystalline diamond films synthesized by focused microwave Ar/CH4/H2 plasma jets

    International Nuclear Information System (INIS)

    Liao, Wen-Hsiang; Lin, Chii-Ruey; Wei, Da-Hua

    2013-01-01

    The effects of CH 4 concentration (0.5–5%) on the growth mechanisms, nanostructures, and optically transparent properties of ultrananocrystalline diamond (UNCD) films grown from focused microwave Ar/CH 4 /H 2 (argon-rich) plasma jets were systematically studied. The research results indicated that the grain size and surface roughness of the diamond films increased with increasing CH 4 concentration in the plasma jet, however, the nondiamond contents in films would not be correspondingly decreased resulting from the dispersed diamond nanocrystallites in the films synthesized at higher CH 4 concentration. The reason is due to that the relative emission intensity ratios of the C 2 /H α and the CH/C 2 in the plasma jets were increased and decreased with increasing CH 4 concentration, respectively, to lower the etching of nondiamond phase and the renucleation of diamond during synthesis. The studies of transmission electron microscopy demonstrated that, while the CH 4 introduction of 1% into the plasma jet produced the UNCD films with a spherical geometry (4–8 nm) and the CH 4 introduction of 5% into the plasma jet led to the elongated (∼90 nm in length and ∼35 nm in width) grains in the nanocrystalline diamond (NCD) films with a dendrite-like geometry. The transmittance of diamond films was decreased gradually by films transition from UNCD to NCD, resulting from the enhanced surface roughness and nondiamond contents in films to concurrently increase the light scattering and absorption during photon transmission.

  20. Facilities granted by the authorities to companies certified in accordance with the EC Eco-Audit Ordinance; Behoerdliche Erleichterungen fuer validierte Unternehmen nach der EG-Oeko-Audit-Verordnung

    Energy Technology Data Exchange (ETDEWEB)

    Funda, K. [Witzenhausen-Institut fuer Abfall, Umwelt und Energie, Witzenhausen (Germany)

    1999-07-01

    During the past few years there has been a growing discussion on possible ways of granting facilities and allowing simplified legal procedures for companies which have been certified according to the EU Eco-Audit Regulation and which have thus submitted themselves voluntarily to the requirements of this code. This paper gives an account of the current stage of the discussion and describes the facilities currently granted by the German federal states to certified companies. It is largely based on the relevant regulations and decrees issued by the federal states as chief enactors of environmental law and on information given orally and in writing by the various ministries involved in the data search carried out between January and March 1999. [German] In den letzten Jahren wurde zunehmend die Frage nach ordnungsrechtlichen Erleichterungen und Vereinfachungen fuer Unternehmen diskutiert, die eine Validierung nach der EG-Oeko-Audit-Verordnung durchgefuehrt und sich damit freiwillig den Anforderungen dieses Regelwerkes unterworfen haben. Der vorliegende Beitrag versucht den aktuellen Stand dieser Diskussion zu beleuchten und die zur Zeit von den Bundeslaendern eingeraeumten Erleichterungen fuer Unternehmen darzustellen. Grundlage der Aussagen sind im wesentlichen die einschlaegigen Vorschriften und Erlasse der Laender, in deren Hand zum groessten Teil der Vollzug des Umweltrechtes liegt, sowie muendliche und schriftliche Informationen aus den verschiedenen Fachministerien, die im Rahmen einer Datenrecherche zwischen Januar und Maerz 1999 zusammengetragen wurden. (orig.)

  1. Hinderniserkennung und -verfolgung mit einer PMD-kamera im automobil

    Science.gov (United States)

    Schamm, Thomas; Vacek, Stefan; Natroshvilli, Koba; Marius Zöllner, J.; Dillmann, Rüdiger

    Die Detektion von Hindernissen vor dem Automobil ist eine Hauptanforderung an moderne Fahrerassistenzsysteme (FAS). In dieser Arbeit wird ein System vorgestellt, das mit Hilfe einer PMDKamera (Photomischdetektor) Hindernisse auf der Fahrspur erkennt und deren relevante Parameter bestimmt. Durch die PMD-Kamera werden zunächst 3D-Tiefenbilder der Fahrzeugumwelt generiert. Nach einem initialen Filterprozess werden im Tiefenbild mit Hilfe eines Bereichswachstumsverfahrens Hindernisse gesucht. Zur Stabilisierung des Verfahrens und zur Parameterberechnung wird ein Kaiman Filter eingesetzt. Das Ergebnis ist eine Liste aller Hindernisse im Fahrbereich des Automobils.

  2. Uncertainties in modelling CH4 emissions from northern wetlands in glacial climates: the role of vegetation parameters

    Directory of Open Access Journals (Sweden)

    J. van Huissteden

    2011-10-01

    Full Text Available Marine Isotope Stage 3 (MIS 3 interstadials are marked by a sharp increase in the atmospheric methane (CH4 concentration, as recorded in ice cores. Wetlands are assumed to be the major source of this CH4, although several other hypotheses have been advanced. Modelling of CH4 emissions is crucial to quantify CH4 sources for past climates. Vegetation effects are generally highly generalized in modelling past and present-day CH4 fluxes, but should not be neglected. Plants strongly affect the soil-atmosphere exchange of CH4 and the net primary production of the vegetation supplies organic matter as substrate for methanogens. For modelling past CH4 fluxes from northern wetlands, assumptions on vegetation are highly relevant since paleobotanical data indicate large differences in Last Glacial (LG wetland vegetation composition as compared to modern wetland vegetation. Besides more cold-adapted vegetation, Sphagnum mosses appear to be much less dominant during large parts of the LG than at present, which particularly affects CH4 oxidation and transport. To evaluate the effect of vegetation parameters, we used the PEATLAND-VU wetland CO2/CH4 model to simulate emissions from wetlands in continental Europe during LG and modern climates. We tested the effect of parameters influencing oxidation during plant transport (fox, vegetation net primary production (NPP, parameter symbol Pmax, plant transport rate (Vtransp, maximum rooting depth (Zroot and root exudation rate (fex. Our model results show that modelled CH4 fluxes are sensitive to fox and Zroot in particular. The effects of Pmax, Vtransp and fex are of lesser relevance. Interactions with water table modelling are significant for Vtransp. We conducted experiments with different wetland vegetation types for Marine Isotope Stage 3 (MIS 3 stadial and interstadial climates and the present-day climate, by coupling PEATLAND-VU to high resolution climate model simulations for Europe. Experiments assuming

  3. Uncertainties in modelling CH4 emissions from northern wetlands in glacial climates: the role of vegetation parameters

    Science.gov (United States)

    Berrittella, C.; van Huissteden, J.

    2011-10-01

    Marine Isotope Stage 3 (MIS 3) interstadials are marked by a sharp increase in the atmospheric methane (CH4) concentration, as recorded in ice cores. Wetlands are assumed to be the major source of this CH4, although several other hypotheses have been advanced. Modelling of CH4 emissions is crucial to quantify CH4 sources for past climates. Vegetation effects are generally highly generalized in modelling past and present-day CH4 fluxes, but should not be neglected. Plants strongly affect the soil-atmosphere exchange of CH4 and the net primary production of the vegetation supplies organic matter as substrate for methanogens. For modelling past CH4 fluxes from northern wetlands, assumptions on vegetation are highly relevant since paleobotanical data indicate large differences in Last Glacial (LG) wetland vegetation composition as compared to modern wetland vegetation. Besides more cold-adapted vegetation, Sphagnum mosses appear to be much less dominant during large parts of the LG than at present, which particularly affects CH4 oxidation and transport. To evaluate the effect of vegetation parameters, we used the PEATLAND-VU wetland CO2/CH4 model to simulate emissions from wetlands in continental Europe during LG and modern climates. We tested the effect of parameters influencing oxidation during plant transport (fox), vegetation net primary production (NPP, parameter symbol Pmax), plant transport rate (Vtransp), maximum rooting depth (Zroot) and root exudation rate (fex). Our model results show that modelled CH4 fluxes are sensitive to fox and Zroot in particular. The effects of Pmax, Vtransp and fex are of lesser relevance. Interactions with water table modelling are significant for Vtransp. We conducted experiments with different wetland vegetation types for Marine Isotope Stage 3 (MIS 3) stadial and interstadial climates and the present-day climate, by coupling PEATLAND-VU to high resolution climate model simulations for Europe. Experiments assuming dominance of

  4. Entsorgungswirtschaft zwischen Grünem Punkt und Dosenpfand

    OpenAIRE

    Johann Wackerbauer

    2003-01-01

    Die Zeiten der hohen Wachstumsraten in der Abfallentsorgung dürften vorbei sein. Die Nachfrage nach Entsorgungsleistungen wird stärker von der Umweltpolitik als von der allgemeinen Konjunkturentwicklung beeinflusst. Die Turbulenzen im Zusammenhang mit der Einführung der Pfandpflicht auf Einweggetränkeverpackungen und die Diskussion um die Monopolstellung der Gesellschaft »Der Grüne Punkt - Duales System Deutschland AG« im Bereich der Entsorgung von Verkaufsverpackungen haben die Entsorgungs...

  5. Politische Bildung im Kontext von Regierung, Unterricht und Zucht

    Directory of Open Access Journals (Sweden)

    Thomas Rucker

    2014-02-01

    Full Text Available Johann Friedrich Herbart (1776-1841 gilt als der Begründer der wissenschaftlichen Pädagogik. In diesem Beitrag wird zu zeigen versucht, dass Herbart die Unterstützung politischer Bildung als eine Aufgabe von Regierung, Unterricht und Zucht bestimmt und in seinem Werk wichtige „Bausteine“ für eine Theorie der politischen Bildung unter den Bedingungen von Erziehung vorlegt hat. Nach Herbart ist das politische Selbst- und Weltverhältnis auf Sachverhalte bezogen, die nicht nur die Lebensführung einzelner Menschen, sondern die Lebensführung einer Mehrzahl von Menschen betreffen. Nicht das Zusammenleben von Menschen generell ist jedoch Orientierungsgesichtspunkt des politischen Selbst- und Weltverhältnisses, sondern nur das problematisch gewordene Zusammenleben. Politik ergibt sich nach Herbart aus einem Konflikt hinsichtlich der Frage, wie das Zusammenleben von Menschen geregelt sein sollte. Während die Regierung lediglich mittelbar einen Beitrag zur politischen Bildung leistet, indem sie die Voraussetzungen für Unterricht und Zucht bereitstellt, fungieren die beiden zuletzt genannten Formen von Erziehung als die eigentlichen Medien, in denen die politische Bildung im Sinne Herbarts ihren Ort hat.

  6. Beckenbodenbeschwerden bei Fahrradfahrerinnen und mögliche Therapieansätze

    Directory of Open Access Journals (Sweden)

    Lyatoshinsky P

    2016-01-01

    Full Text Available Einleitung und Hypothese: Fahrradfahren ist nicht nur ein immer beliebter werdender Freizeitsport, sondern auch ein immer intensiver genutztes Fortbewegungsmittel. Somit ist es mittlerweile von großer Bedeutung, herauszufinden, welchen negativen Einfluss das Fahrradfahren auf den menschlichen Körper hat. Dieser Review fasst die aktuelle Evidenz zur Epidemiologie, Therapie und Prävention der Genital- und Beckenbodenbeschwerden bei weiblichen Fahrradfahrerinnen zusammen.brMethoden: Zwei Metadatenbanken, OvidSP und Deutsches Institut für Medizinische Dokumentation und Information (DIMDI, wurden auf Studien durchsucht, die über Genital- und Beckenbodenbeschwerden bei weiblichen Fahrradfahrerinnen berichteten und mögliche Therapie- oder Prophylaxeansätze untersuchten. Für die Literaturrecherche wurden folgende Schlagwörter verwendet: „female“, „bicycling“, „pelvic floor“, „lower urinary tract symptoms“ und „vulvar diseases“.brErgebnis: Die Suche ergab 1219 Artikel. Nach Entfernen der Duplikate aus dem Ergebnispool wurden 763 Publikationen nach relevanten Titeln untersucht. Letztendlich konnten 12 Fachartikel für unser Review herangezogen werden. 10 Studien waren Beobachtungsstudien und 2 experimentell. Symptome, die hierbei mit Fahrradfahren assoziiert wurden, waren: Schmerz und Neuropathien in der Beckenbodenregion sowie urologische Dysfunktionen und Hautverletzungen. Breitere und konventionelle Sättel führten zu einer geringeren Symptomatik als Sättel mit einer Lochung sowie schmälere Sportsättel.brZusammenfassung: Die Qualität der gegenwärtigen Studien war im Allgemeinen niedrig. Dennoch gibt es Evidenz dafür, dass Radfahrerinnen unter sehr ähnlichen Symptomen leiden wie Radfahrer: von kleineren Hautläsionen bis hin zu neurologischen Beschwerden.

  7. Das Alter ist der wichtigste Risikofaktor der postoperativen erektilen Dysfunktion nach radikaler nerverhaltender Prostatektomie

    Directory of Open Access Journals (Sweden)

    Gruschka M

    2009-01-01

    Full Text Available Die radikale Prostatektomie ohne Nerverhalt geht mit Impotenz einher. Bei nerverhaltendem Vorgehen kann das Risiko der erektilen Dysfunktion gesenkt, aber nicht ausgeschlossen werden. Die präoperative Beratung der Patienten erfordert bei nerverhaltender Prostatektomie die Kenntnis der Faktoren, die Einfluss auf die postoperative Potenz haben. Patienten & Methoden: 110 Patienten antworteten 24 Monate nach radikaler perinealer nerverhaltender Prostatektomie auf einen per Post übermittelten Fragebogen. Die Patienten wurden, entsprechend dem Erection Hardness Score, nach der Rigidität ihrer Erektionen befragt. Überwiegend erfolgte der Nerverhalt unilateral (104/110. Verschiedene potenzielle Risikofaktoren (Alter, Qualität der präoperativen Erektion, Serum-PSA, Gleason-Score, Tumorvolumen, Prostatavolumen, adjuvante Strahlentherapie, ASA-Score, Chronic Disease Score [CDS], arterielle Hypertonie, Hypercholesterinämie, Diabetes mellitus, KHK, Nikotinkonsum wurden univariat mit der postoperativ erzielten Potenz korreliert. Multivariat wurden dann jene Parameter untersucht, die in der univariaten Analyse einen signifikanten (p ≤ 0,05 oder einen tendenziellen Zusammenhang (p ≤ 0,2 mit der postoperativen erektilen Funktion aufwiesen. Ergebnisse:Das Alter (p 0,001 und der ASAScore (p = 0,018 waren in der univariaten Analyse negative Prädiktoren der postoperativen Potenz. In der multivariaten Analyse war lediglich das Alter (p = 0,028 von signifikanter Bedeutung. Mit jedem Lebensjahr der Männer steigt das Risiko einer um eine Stufe im EHS schlechteren Erektion um das 1,128-Fache an. Bei einem Altersunterschied von 10 Jahren ist das Risiko eines postoperativ schlechteren Erektionsvermögens um den Faktor 3,334 erhöht, bei einem um 20 Jahre höheren Alter beträgt dieser Faktor 11,121. Diskussion & Praxisrelevanz: Das Lebensalter der Patienten wurde im Einklang mit der Literatur als signifikanter Faktor für die postoperative Potenz identifiziert

  8. Perception and processing of information relevant to critical incidents and emergencies; Wahrnehmung und Verarbeitung stoer- und unfallrelevanter Informationen

    Energy Technology Data Exchange (ETDEWEB)

    Dombrowsky, W.R. [Kiel Univ. (Germany). Katastrophenforschungsstelle

    1997-12-31

    Based on the results of empirical research, which implemented and evaluated information to the public requested by law (HIO-Paragraph-11a) and based on the general findings of crisis- and risk-communication research, some disturbing elements in the relationship between entrepreneurs, administration and the public will be described in terms of cognitive dissonance, prejudice, fears and false expectations. The empirical example of public information in emergencies will evidence the conflicting views on types, styles, size and profoundity of such information as well as the differences in perception, motivation and interest of all parties involved. Finally, the cultural context of risk perception and of coping capabilities will be interrelated with historical changes of risk-management to prepare for the understanding that risk- and crisis communication has to be more than talking about safety. (orig.) [Deutsch] Am Beispiel einer Implementations- und Evaluationsforschung zur Erstellung von Stoerfallinformationen nach Paragraph 11a BimSchG fuer zwei Unternehmen und auf Basis des Kenntnisstandes der internationalen Forschung zur Krisen- und Risikokommunikation wird verdeutlicht, welche kognitiven Dissonanzen zwischen Anlagenbetreibern, Behoerden und Bevoelkerung ueber Art, Umfang und Gestaltung von Gefahrinformationen bestehen, welche Vorurteile und Aengste eine sachliche Kommunikation behindern, welche gesellschaftlichen Faktoren bislang weitgehend uebersehen wurden, was von wem fuer `stoer- und unfallrelevant` gehalten wird und welche gesellschaftlichen, sozialen `settings`, d.h. welche menschlichen Bedingungen die Wahrnehmung und Verarbeitung welcher Informationen beeinflussen. Darin liegt die empirische Bestaetigung der Hypothese, dass sich die Wahrnehmung von Risiken und Bedrohungen historisch kurzfristig (bereits innerhalb einer Generation) veraendert und es keine `one-for-all`-Strategie der Risiko- und Krisenkommunikation geben kann, wohl aber allgemeine

  9. In-situ studies of microbial CH4 oxidation efficiency in Arctic wetland soils. Applications of stable carbon isotopes

    International Nuclear Information System (INIS)

    Preuss, Inken-Marie

    2013-01-01

    Arctic wetland soils are significant sources of the climate-relevant trace gas methane (CH 4 ). The observed accelerated warming of the Arctic is expected to cause deeper permafrost thawing followed by increased carbon mineralization and CH 4 formation in water-saturated permafrost-affected tundra soils thus creating a positive feedback to climate change. Aerobic CH 4 oxidation is regarded as the key process reducing CH 4 emissions from wetlands, but quantification of turnover rates has remained difficult so far. This study improved the in-situ quantification of microbial CH 4 oxidation efficiency in arctic wetland soils in Russia's Lena River Delta based on stable isotope signatures of CH 4 . In addition to the common practice of determining the stable isotope fractionation during oxidation, additionally the fractionation effect of diffusion, an important gas transport mechanism in tundra soils, was investigated for both saturated and unsaturated conditions. The isotopic fractionation factors α ox and α diff were used to calculate the CH 4 oxidation efficiency from the CH 4 stable isotope signatures of wet polygonal tundra soils of different hydrology. Further, the method was used to study the short-term effects of temperature increase with a climate manipulation experiment. For the first time, the stable isotope fractionation of CH 4 diffusion through water-saturated soils was determined with α diff = 1.001 ± 0.0002 (n = 3). CH 4 stable isotope fractionation during diffusion through air-filled pores of the investigated polygonal tundra soils was α diff = 1.013 ± 0.003 (n = 18). For the studied sites the fractionation factor for diffusion under saturated conditions α diff = 1.001 seems to be of utmost importance for the quantification of the CH 4 oxidation efficiency, since most of the CH 4 is oxidized in the saturated part at the aerobic-anaerobic interface. Furthermore, it was found that α ox differs widely between sites and horizons (mean α ox = 1

  10. CO2 adsorption-assisted CH4 desorption on carbon models of coal surface: A DFT study

    Science.gov (United States)

    Xu, He; Chu, Wei; Huang, Xia; Sun, Wenjing; Jiang, Chengfa; Liu, Zhongqing

    2016-07-01

    Injection of CO2 into coal is known to improve the yields of coal-bed methane gas. However, the technology of CO2 injection-enhanced coal-bed methane (CO2-ECBM) recovery is still in its infancy with an unclear mechanism. Density functional theory (DFT) calculations were performed to elucidate the mechanism of CO2 adsorption-assisted CH4 desorption (AAD). To simulate coal surfaces, different six-ring aromatic clusters (2 × 2, 3 × 3, 4 × 4, 5 × 5, 6 × 6, and 7 × 7) were used as simplified graphene (Gr) carbon models. The adsorption and desorption of CH4 and/or CO2 on these carbon models were assessed. The results showed that a six-ring aromatic cluster model (4 × 4) can simulate the coal surface with limited approximation. The adsorption of CO2 onto these carbon models was more stable than that in the case of CH4. Further, the adsorption energies of single CH4 and CO2 in the more stable site were -15.58 and -18.16 kJ/mol, respectively. When two molecules (CO2 and CH4) interact with the surface, CO2 compels CH4 to adsorb onto the less stable site, with a resulting significant decrease in the adsorption energy of CH4 onto the surface of the carbon model with pre-adsorbed CO2. The Mulliken charges and electrostatic potentials of CH4 and CO2 adsorbed onto the surface of the carbon model were compared to determine their respective adsorption activities and changes. At the molecular level, our results showed that the adsorption of the injected CO2 promoted the desorption of CH4, the underlying mechanism of CO2-ECBM.

  11. Schule und Bildung im Prozess der Globalisierung

    Directory of Open Access Journals (Sweden)

    Jürgen Oelkers

    2000-05-01

    Full Text Available Der Autor erörtert die Auswirkungen der Globalisierung auf Schulen, Lern- und Lehrarrangements sowie die künftige Rolle der Bildung innerhalb der vernetzten, entgrenzten Lebensräume. Dabei geht er der Frage nach, welche Rolle die Schule als traditionell ortsgebundene Einrichtung hinsichtlich der Vorbereitung auf einen globalem Arbeitsmarkt mit seinen Unsicherheiten einnehmen kann. Zunächst beschreibt er allgemeine Tendenzen der Individualisierung und Flexiblisierung von Arbeitsbedingungen, um Konsequenzen für die Kindheit abzuleiten (Zeit der Eltern als knappes Gut, Kommerzialisierung. In einem zweiten Schritt verdeutlicht er, welche Auswirkungen die neuen Medien Internet und Computer für das Lernen haben (Ungebundenheit hinsichtlich Ort, Zeit, damit verknüpft die Unverlässlichkeit von Quellen. In einem letzten Schritt charakterisiert er die Konsequenzen der Globalisierung für die Bildung und die Schule (internationale Standards in den drei großen Wirtschaftsräumen, Notwendigkeit der Vermittlung von Wissen zur Strukturierung und Bewertung von Informationen.

  12. Expanding Spatial and Temporal Coverage of Arctic CH4 and CO2 Fluxes

    Science.gov (United States)

    Murphy, P.; Oechel, W. C.; Moreaux, V.; Losacco, S.; Zona, D.

    2013-12-01

    Carbon storage and exchange in Arctic ecosystems is the subject of intensive study focused on determining rates, controls, and mechanisms of CH4 and CO2 fluxes. The Arctic contains more than 1 Gt of Carbon in the upper meter of soil, both in the active layer and permafrost (Schuur et al., 2008; Tarnocai et al., 2009). However, the annual pattern and controls on the release of CH4 is inadequately understood in Arctic tundra ecosystems. Annual methane budgets are poorly understood, and very few studies measure fluxes through the freeze-up cycle during autumn months (Mastepanov et al., 2008; Mastepanov et al., 2010; Sturtevant et al., 2012). There is no known, relatively continuous, CH4 flux record for the Arctic. Clearly, the datasets that currently exist for budget calculations and model parameterization and verification are inadequate. This is likely due to the difficult nature of flux measurements in the Arctic. In September 2012, we initiated a research project towards continuous methane flux measurements along a latitudinal transect in Northern Alaska. The eddy-covariance (EC) technique is challenging in such extreme weather conditions due to the effects of ice formation and precipitation on instrumentation, including gas analyzers and sonic anemometers. The challenge is greater in remote areas of the Arctic, when low power availability and limited communication can lead to delays in data retrieval or data loss. For these reasons, a combination of open- and closed-path gas analyzers, and several sonic anemometers (including one with heating), have been installed on EC towers to allow for cross-comparison and cross-referencing of calculated fluxes. Newer instruments for fast CH4 flux determination include: the Los Gatos Research Fast Greenhouse Gas Analyzer and the Li-Cor LI-7700. We also included the self-heated Metek Class-A uSonic-3 Anemometer as a new instrument. Previously existing instruments used for comparison include the Li-Cor LI-7500; Li-Cor LI-7200

  13. Teilen, Sharing 1 und Sharing 2: die Sharing Economy im Licht theoretischer Zugänge

    OpenAIRE

    Haase, Michaela; Pick, Doreén

    2016-01-01

    Der Artikel geht theoretischen Zugängen zum Sharing-Begriff nach. Er erläutert den Beitrag, aber auch die Grenzen von Dienstleistungstheorie und Property-Rights-Theorie für das Verständnis der Sharing Economy. Gründe für die Unterscheidung zwischen kommerzieller und nichtkommerzieller Sharing Economy werden dargelegt sowie mögliche Impulse der Sharing Economy für Änderungen im Verständnis wirtschaftlichen Handels und seiner Organisationsformen erörtert. This article elaborates on theoretic...

  14. Die Ukraine-Krise und kritische Fragen an die EU-Erweiterungspolitik

    OpenAIRE

    Lippert, Barbara

    2014-01-01

    Die Ukraine-Krise konfrontiert die EU mit kritischen Fragen zu ihrer Erweiterungs-politik. Muss sie nach der Osterweiterung 2004/07 und dem gerade erst begonnenen Einzug der Westbalkan-Staaten nun mit Osteuropa für die übernächste Erweiterungs-runde rechnen? Sollte sie sich gar alsbald politisch verpflichten, interessierte und beitrittsfähige osteuropäische Länder eines Tages aufzunehmen? Wie jetzt auch viel-fach von EU-Akteuren geäußert, wäre dies voreilig: Denn in der konfliktgeladenen und ...

  15. Experimental measurements of vapor-liquid equilibria of the H2O + CO2 + CH4 ternary system

    Science.gov (United States)

    Qin, J.; Rosenbauer, R.J.; Duan, Zhenhao

    2008-01-01

    Reported are the experimental measurements on vapor-liquid equilibria in the H2O + CO2 + CH4 ternary system at temperatures from (324 to 375) K and pressures from (10 to 50) MPa. The results indicate that the CH4 solubility in the ternary mixture is about 10 % to 40 % more than that calculated by interpolation from the Henry's law constants of the binary system, H2O + CH4, and the solubility of CO2 is 6 % to 20 % more than what is calculated by the interpolation from the Henry's law constants of the binary mixture, H 2O + CO2. ?? 2008 American Chemical Society.

  16. The relationship between termite mound CH4/CO2 emissions and internal concentration ratios are species specific

    Science.gov (United States)

    Jamali, H.; Livesley, S. J.; Hutley, L. B.; Fest, B.; Arndt, S. K.

    2012-12-01

    1. We investigated the relative importance of CH4 and CO2 fluxes from soil and termite mounds at four different sites in the tropical savannas of Northern Australia near Darwin and assessed different methods to indirectly predict CH4 fluxes based on CO2 fluxes and internal gas concentrations. 2. The annual flux from termite mounds and surrounding soil was dominated by CO2 with large variations among sites. On a CO2-e basis, annual CH4 flux estimates from termite mounds were 5- to 46-fold smaller than the concurrent annual CO2 flux estimates. Differences between annual soil CO2 and soil CH4 (CO2-e) fluxes were even greater, soil CO2 fluxes being almost three orders of magnitude greater than soil CH4 (CO2-e) fluxes at site. 3. There were significant relationships between mound CH4 flux and mound CO2 flux, enabling the prediction of CH4 flux from measured CO2 flux, however, these relationships were clearly termite species specific. 4. We also observed significant relationships between mound flux and gas concentration inside mound, for both CH4 and CO2, and for all termite species, thereby enabling the prediction of flux from measured mound internal gas concentration. However, these relationships were also termite species specific. Using the relationship between mound internal gas concentration and flux from one species to predict mound fluxes from other termite species (as has been done in past) would result in errors of more than 5-fold for CH4 and 3-fold for CO2. 5. This study highlights that CO2 fluxes from termite mounds are generally more than one order of magnitude greater than CH4 fluxes. There are species-specific relationships between CH4 and CO2 fluxes from a~mound, and between the inside mound concentration of a gas and the mound flux emission of the same gas, but these relationships vary greatly among termite species. Consequently, there is no generic relationship that will allow for the prediction of CH4 fluxes from termite mounds of all species.

  17. Complications following surgery and adjuvant irradiation in rectal carcinoma. Komplikationen nach Operation und nach adjuvanter Bestrahlung beim Rektumkarzinom

    Energy Technology Data Exchange (ETDEWEB)

    Suhr, P.; Limmer, J. (Ulm Univ. (Germany, F.R.). Universitaetsklinikum)

    1991-04-12

    Colorectal cancer is one of the most common human malignancies. Adjuvant irradiation can decrease the risk of recurrence and subsequently the associated morbidity compared with surgery alone. The rate of radiation-induced complications amounts to approximately 10%, which is substantially lower than the frequency of observed local failure. (orig.).

  18. The Extent of CH4 Emission and Oxidation in Thermogenic and Biogenic Gas Hydrate Environments

    Science.gov (United States)

    Kastner, M.; Solem, C.; Bartlett, D.; MacDonald, I.; Valentine, D.

    2003-12-01

    The role of methane hydrate in the global methane budget is poorly understood, because relatively little is known about the transport of gaseous and dissolved methane through the seafloor into the ocean, from the water column into the atmosphere, and the extent of water-column methanotrophy that occurs en route. We characterize the transport and consumption of methane in three distinct gas hydrate environments, spanning the spectrum of thermogenic and biogenic methane occurrences: Bush Hill in the Gulf of Mexico, Eel River off the coast of Northern California, and the Noth and South Hydrate Ridges on the Cascadia Oregon margin. At all the sites studied a significant enrichment in δ 13CH4 with distance along isopycnals away from the methane source is observed, indicative of extensive aerobic bacterial methane oxidation in the water column. The effects of this process are principally pronounced in the mostly biogenic methane setting, with δ 13C-CH4 measured as high as -12 permil (PDB) between North and South Hydrate Ridge. The δ 13C-CH4 values ranged from -12 to -67 permil at Hydrate Ridge, -34 to -52 permil at Eel River, and -41 to -49 permil at Bush Hill. The large variation in methane carbon isotope ranges between the sites suggest that major differences exist in both the rates of aerobic methane oxidation and system openness at the studied locations. A mean kinetic isotope fractionation factor is being determined using a closed-system Rayleigh distillation model. An approximate regional methane flux from the ocean into the atmosphere is being estimated for the Gulf of Mexico, by extrapolation of the flux value from the Bush Hill methane plume over 390 plume locations having persistent oil slicks on the ocean surface, mapped by time series satellite data.

  19. Evaluating CO2 and CH4 dynamics of Alaskan ecosystems during the Holocene Thermal Maximum

    Science.gov (United States)

    He, Yujie; Jones, Miriam C.; Zhuang, Qianlai; Bochicchio, Christopher; Felzer, B. S.; Mason, Erik; Yu, Zicheng

    2014-01-01

    The Arctic has experienced much greater warming than the global average in recent decades due to polar amplification. Warming has induced ecological changes that have impacted climate carbon-cycle feedbacks, making it important to understand the climate and vegetation controls on carbon (C) dynamics. Here we used the Holocene Thermal Maximum (HTM, 11–9 ka BP, 1 ka BP = 1000 cal yr before present) in Alaska as a case study to examine how ecosystem Cdynamics responded to the past warming climate using an integrated approach of combining paleoecological reconstructions and ecosystem modeling. Our paleoecological synthesis showed expansion of deciduous broadleaf forest (dominated by Populus) into tundra and the establishment of boreal evergreen needleleaf and mixed forest during the second half of the HTM under a warmer- and wetter-than-before climate, coincident with the occurrence of the highest net primary productivity, cumulative net ecosystem productivity, soil C accumulation and CH4 emissions. These series of ecological and biogeochemical shifts mirrored the solar insolation and subsequent temperature and precipitation patterns during HTM, indicating the importance of climate controls on C dynamics. Our simulated regional estimate of CH4 emission rates from Alaska during the HTM ranged from 3.5 to 6.4 Tg CH4 yr−1 and highest annual NPP of 470 Tg C yr−1, significantly higher than previously reported modern estimates. Our results show that the differences in static vegetation distribution maps used in simulations of different time slices have greater influence on modeled C dynamics than climatic fields within each time slice, highlighting the importance of incorporating vegetation community dynamics and their responses to climatic conditions in long-term biogeochemical modeling.

  20. High-accuracy continuous airborne measurements of greenhouse gases (CO2 and CH4) during BARCA

    Science.gov (United States)

    Chen, H.; Winderlich, J.; Gerbig, C.; Hoefer, A.; Rella, C. W.; Crosson, E. R.; van Pelt, A. D.; Steinbach, J.; Kolle, O.; Beck, V.; Daube, B. C.; Gottlieb, E. W.; Chow, V. Y.; Santoni, G. W.; Wofsy, S. C.

    2009-12-01

    High-accuracy continuous measurements of greenhouse gases (CO2 and CH4) during the BARCA (Balanço Atmosférico Regional de Carbono na Amazônia) phase B campaign in Brazil in May 2009 were accomplished using a newly available analyzer based on the cavity ring-down spectroscopy (CRDS) technique. This analyzer was flown without a drying system or any in-flight calibration gases. Water vapor corrections associated with dilution and pressure-broadening effects for CO2 and CH4 were derived from laboratory experiments employing measurements of water vapor by the CRDS analyzer. Before the campaign, the stability of the analyzer was assessed by laboratory tests under simulated flight conditions. During the campaign, a comparison of CO2 measurements between the CRDS analyzer and a nondispersive infrared (NDIR) analyzer on board the same aircraft showed a mean difference of 0.22±0.09 ppm for all flights over the Amazon rain forest. At the end of the campaign, CO2 concentrations of the synthetic calibration gases used by the NDIR analyzer were determined by the CRDS analyzer. After correcting for the isotope and the pressure-broadening effects that resulted from changes of the composition of synthetic vs. ambient air, and applying those concentrations as calibrated values of the calibration gases to reprocess the CO2 measurements made by the NDIR, the mean difference between the CRDS and the NDIR during BARCA was reduced to 0.05±0.09 ppm, with the mean standard deviation of 0.23±0.05 ppm. The results clearly show that the CRDS is sufficiently stable to be used in flight without drying the air or calibrating in flight and the water corrections are fully adequate for high-accuracy continuous airborne measurements of CO2 and CH4.

  1. CMS (Carbon Monitoring System) Methane (CH4) Flux for North America 0.5 degree x 0.667 degree V1 (CMS_CH4_FLX_NA) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The CMS Methane (CH4) Flux for North America data set contains estimates of methane emission in North America based on an inversion of the GEOS-Chem chemical...

  2. PEBAX®/PAN Hollow Fiber Membranes for CO2/CH4 Separation

    Czech Academy of Sciences Publication Activity Database

    Esposito, E.; Clarizia, G.; Bernardo, P.; Jansen, J. C.; Sedláková, Zuzana; Izák, Pavel; Curcio, S.; de Cindio, B.; Tasselli, F.

    2015-01-01

    Roč. 94, SI (2015), s. 53-61 ISSN 0255-2701. [International Congress of Chemical and Process Engineering CHISA 2014 /21./ and Conference PRES 2014 /17./. Prague, 23.08.2014-27.08.2014] R&D Projects: GA ČR GA14-12695S Grant - others:INRP(IT) MicroPERLA:PON01_01840 Institutional support: RVO:67985858 Keywords : composite membrane * hollow fibers * CO2/CH4 separation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.154, year: 2015

  3. Bayesian model comparison using Gauss approximation on multicomponent mass spectra from CH4 plasma

    International Nuclear Information System (INIS)

    Kang, H.D.; Dose, V.

    2004-01-01

    We performed Bayesian model comparison on mass spectra from CH4 rf process plasmas to detect radicals produced in the plasma. The key ingredient for its implementation is the high-dimensional evidence integral. We apply Gauss approximation to evaluate the evidence. The results were compared with those calculated by the thermodynamic integration method using Markov Chain Monte Carlo technique. In spite of very large difference in the computation time between two methods a very good agreement was obtained. Alternatively, a Monte Carlo integration method based on the approximated Gaussian posterior density is presented. Its applicability to the problem of mass spectrometry is discussed

  4. Vapor-liquid equilibrium thermodynamics of N2 + CH4 - Model and Titan applications

    Science.gov (United States)

    Thompson, W. R.; Zollweg, John A.; Gabis, David H.

    1992-01-01

    A thermodynamic model is presented for vapor-liquid equilibrium in the N2 + CH4 system, which is implicated in calculations of the Titan tropospheric clouds' vapor-liquid equilibrium thermodynamics. This model imposes constraints on the consistency of experimental equilibrium data, and embodies temperature effects by encompassing enthalpy data; it readily calculates the saturation criteria, condensate composition, and latent heat for a given pressure-temperature profile of the Titan atmosphere. The N2 content of condensate is about half of that computed from Raoult's law, and about 30 percent greater than that computed from Henry's law.

  5. Carbon nanosheets by microwave plasma enhanced chemical vapor deposition in CH4-Ar system

    International Nuclear Information System (INIS)

    Wang Zhipeng; Shoji, Mao; Ogata, Hironori

    2011-01-01

    We employ a new gas mixture of CH 4 -Ar to fabricate carbon nanosheets by microwave plasma enhanced chemical vapor deposition at the growth temperature of less than 500 deg. C. The catalyst-free nanosheets possess flower-like structures with a large amount of sharp edges, which consist of a few layers of graphene sheets according to the observation by transmission electron microscopy. These high-quality carbon nanosheets demonstrated a faster electron transfer between the electrolyte and the nanosheet surface, due to their edge defects and graphene structures.

  6. Field detection of CO and CH4 by NIR 2f modulation laser spectroscopy

    Directory of Open Access Journals (Sweden)

    A Khorsandi

    2011-12-01

    Full Text Available   A novel compact fiber-coupled NIR system based on a DFB diode laser source is employed as a portable and sensitive gas sensor for trace detection of combustion pollutant molecules. We demonstrate the performance of such an NIR gas sensor by tracing the absorption lines of CO and CH4 using 2f-WMS technique at moderate temperature of T ~ 600°C in the recuperator channel of an industrial furnace provided by Mobarakeh steel company. This measurement shows the excellent sensitivity of the applied NIR gas sensor to the on-line and in-situ monitoring of such molecular species.

  7. Experimental confirmation of the Jahn-Teller distortion of CH4+

    International Nuclear Information System (INIS)

    Gemmell, D.S.; Kanter, E.P.; Pietsch, W.J.

    1979-01-01

    Measured energy and angular distributions are reported for H + and C/sup n+/ (n = 2,3,4) fragments resulting from the collisional dissociation of 200-keV/amu CH/sub m/ + (m = 0 to 4) in thin carbon targets. From the systematic trends of these Coulomb explosion spectra, qualitative information can be obtained on the structures of these species. In particular, the series displays a narrowing of the carbon angular and energy widths as protons are symmetrically added around a central carbon atom and provide a focusing effect. Because of the Jahn-Teller distortion, the carbon width in CH 4 + is dramatically increased. 8 references

  8. Nitric Oxide Mediates Biofilm Formation and Symbiosis in Silicibacter sp. Strain TrichCH4B.

    Science.gov (United States)

    Rao, Minxi; Smith, Brian C; Marletta, Michael A

    2015-05-05

    Nitric oxide (NO) plays an important signaling role in all domains of life. Many bacteria contain a heme-nitric oxide/oxygen binding (H-NOX) protein that selectively binds NO. These H-NOX proteins often act as sensors that regulate histidine kinase (HK) activity, forming part of a bacterial two-component signaling system that also involves one or more response regulators. In several organisms, NO binding to the H-NOX protein governs bacterial biofilm formation; however, the source of NO exposure for these bacteria is unknown. In mammals, NO is generated by the enzyme nitric oxide synthase (NOS) and signals through binding the H-NOX domain of soluble guanylate cyclase. Recently, several bacterial NOS proteins have also been reported, but the corresponding bacteria do not also encode an H-NOX protein. Here, we report the first characterization of a bacterium that encodes both a NOS and H-NOX, thus resembling the mammalian system capable of both synthesizing and sensing NO. We characterized the NO signaling pathway of the marine alphaproteobacterium Silicibacter sp. strain TrichCH4B, determining that the NOS is activated by an algal symbiont, Trichodesmium erythraeum. NO signaling through a histidine kinase-response regulator two-component signaling pathway results in increased concentrations of cyclic diguanosine monophosphate, a key bacterial second messenger molecule that controls cellular adhesion and biofilm formation. Silicibacter sp. TrichCH4B biofilm formation, activated by T. erythraeum, may be an important mechanism for symbiosis between the two organisms, revealing that NO plays a previously unknown key role in bacterial communication and symbiosis. Bacterial nitric oxide (NO) signaling via heme-nitric oxide/oxygen binding (H-NOX) proteins regulates biofilm formation, playing an important role in protecting bacteria from oxidative stress and other environmental stresses. Biofilms are also an important part of symbiosis, allowing the organism to remain in a

  9. BOREAS TGB-3 CH4 and CO2 Chamber Flux Data over NSA Upland Sites

    Science.gov (United States)

    Savage, Kathleen; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor); Moore, Tim R.

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-3) team collected methane and carbon dioxide (CH4, CO2) chamber flux measurements at the Northern Study Area (NSA) Fen, Old Black Spruce (OBS), Young Jack Pine (YJP), and auxiliary sites along Gillam Road and the 1989 burn site. Gas samples were extracted from chambers and analyzed at the NSA lab facility approximately every 7 days during May to September 1994 and June to October 1996. The data are provided in tabular ASCII files.

  10. Besitzt Mentoring kultur- und strukturverändernde Potenziale? Does Mentoring have Cultural and Structural Changing Potential?

    Directory of Open Access Journals (Sweden)

    Astrid Franzke

    2006-11-01

    Full Text Available Während Mentoring bislang hinsichtlich seiner individuellen Effekte vor allem in theoretischen Arbeiten untersucht und in Evaluationsstudien empirisch ausgewertet worden ist, fragen die Herausgeberinnen nach den kultur- und strukturverändernden Potenzialen durch Mentoring im universitären Feld.Theoretical surveys have examined the individual effects of mentoring and evaluative studies have empirically analyzed these effects. However, the editors inquire into the cultural and structural changing potential of mentoring for the university field.

  11. Environmental and vegetation controls on the spatial variability of CH4 emission from wet-sedge and tussock tundra ecosystems in the Arctic.

    Science.gov (United States)

    McEwing, Katherine Rose; Fisher, James Paul; Zona, Donatella

    Despite multiple studies investigating the environmental controls on CH 4 fluxes from arctic tundra ecosystems, the high spatial variability of CH 4 emissions is not fully understood. This makes the upscaling of CH 4 fluxes from plot to regional scale, particularly challenging. The goal of this study is to refine our knowledge of the spatial variability and controls on CH 4 emission from tundra ecosystems. CH 4 fluxes were measured in four sites across a variety of wet-sedge and tussock tundra ecosystems in Alaska using chambers and a Los Gatos CO 2 and CH 4 gas analyser. All sites were found to be sources of CH 4 , with northern sites (in Barrow) showing similar CH 4 emission rates to the southernmost site (ca. 300 km south, Ivotuk). Gross primary productivity (GPP), water level and soil temperature were the most important environmental controls on CH 4 emission. Greater vascular plant cover was linked with higher CH 4 emission, but this increased emission with increased vascular plant cover was much higher (86 %) in the drier sites, than the wettest sites (30 %), suggesting that transport and/or substrate availability were crucial limiting factors for CH 4 emission in these tundra ecosystems. Overall, this study provides an increased understanding of the fine scale spatial controls on CH 4 flux, in particular the key role that plant cover and GPP play in enhancing CH 4 emissions from tundra soils.

  12. Radiotherapy in early stage dupuytren's contracture; Die Radiotherapie des Morbus Dupuytren im Fruehstadium. Langzeitresultate nach einer medianen Nachbeobachtungszeit von 10 Jahren

    Energy Technology Data Exchange (ETDEWEB)

    Adamietz, B.; Sauer, R. [Erlangen-Nuernberg Univ., Erlangen (Germany). Klinik und Poliklinik fuer Strahlentherapie; Keilholz, L. [Erlangen-Nuernberg Univ., Erlangen (Germany). Klinik und Poliklinik fuer Strahlentherapie; Praxis fuer Strahlentherapie, Klinikum Fuerth (Germany); Gruenert, J. [Abt. fuer Plastische und Handchirurgie der Chirurgischen Universitaetsklinik Erlangen-Nuernberg, Erlangen (Germany)

    2001-11-01

    Purpose: In early stage Dupuytren's contracture radiotherapy was applied to prevent disease progression. Long-term results and late toxicity of this treatment were evaluated in a retrospective analysis. Patients and Methods: Between 1982 and 1994, 99 patients (176 hands) received orthovoltage radiotherapy, which consisted of two courses with 5 x 3 Gy (total dose: 30 Gy, daily fractionated; 120 kV, 4 mm Al), separated by a 6 to 8-week pause. The Dupuytren's contracture was staged according to the classification of Tubiana et al. The long-term outcome was analyzed at last follow-up between July and November 1999. The median follow-up was 10 years (range 7-18 years). Late toxicity was assessed using the LENT-SOMA criteria. Results: In Stage N 84% and Stage N/I 67% of cases remained stable. 65% of the cases in Stage I and 83% in Stage II showed progressive nodules and cords. In case of progression we saw no complications after a second radiotherapy or salvage operation. Conclusion: Radiotherapy effectively prevents disease progression for early stage Dupuytren's contracture (Stage N, N/I). Moreover, in case of disease progression despite radiotherapy salvage surgery is still feasible. (orig.) [German] Hintergrund: Im Fruehstadium des Morbus Dupuytren wird die externe Radiotherapie mit dem Ziel eingesetzt, den progressiven Verlauf der Erkrankung zu verhindern. Eine aktuelle Langzeitverlaufskontrolle soll die Ergebnisse und Nebenwirkungen der Radiotherapie darstellen. Patienten und Methode: Wir untersuchten 99 Patienten (176 Haende), welche sich von 1982-1994 einer Radiotherapie an unserer Klinik unterzogen. Jeder Patient erhielt zwei Serien einer Radiotherapie mit jeweils 5 x 3 Gy (Gesamtdosis 30 Gy, 120 kV, 4 mm Al, Bestrahlungspause von 6-8 Wochen nach 15 Gy). Die Beugekontraktur wurde nach Tubiana et al. eingeteilt. Von Juli bis November 1999 erfolgte nach einer medianen Nachbeobachtungszeit von 10 Jahren (7-18 Jahre) eine Kontrolluntersuchung. Die

  13. Aktuelle Technik der Bruststraffung beim Mann nach Gewichtsverlust [Modern technique in male breast contouring after weight loss

    Directory of Open Access Journals (Sweden)

    Stoff, Alexander

    2013-08-01

    Full Text Available [english] The morbid adiposity and its medical consequences demonstrates a growing problem of our current prosperous society. Due to a significant improvement of bariatric techniques and a reduplication of adipose patients during the 20 century, the number of patients, who present to plastic surgeons with a new degree of suffering, has been growing steadily. Initially, the female patients were in the majority, which has been more balanced nowadays.The male breast is a body region that primarily symbolizes masculinity and strenght. In male patients after massive weight loss, this body region remains as an extremly deflated breast envelope without any sign of possible retraction. The plastic surgeon may choose from different single or combinated ltechniques, which are indicated depending on the local and adjacent tissue characteristics.We are presenting our modified technique of male breast reshaping, referring to the technique of Aly, except for a NAC transposition on a central pedicle. The central pedicle is hereby preserved from resection after tremendous liposuction. This central pedicle technique allows a safe and uncomplicated NAC transposition with significant advantages compared to free NAC-Transposition techniques in terms of aesthetical and functional outcome. [german] Die morbide Adipositas mit ihren Langzeitfolgen ist ein zunehmendes Problem unserer heutigen Wohlstandsgesellschaft. Mit einer Verdoppelung der betroffenen Patienten im Laufe des 20. Jahrhunderts ist gleichzeitig durch rasante Verbesserung der bariatrischen Eingriffe auch die Zahl der Patienten signifikant und stetig gestiegen, die sich nach massiver Gewichtsreduktion nun mit neuem Leidensdruck beim Plastischen Chirurgen vorstellen. Hierbei ist die anfängliche Überzahl der weiblichen Patienten in ein ausgewogenes Verhältnis der betroffenen Geschlechter übergegangen. Die männliche Brust, eine Körperregion, die in erster Linie Männlichkeit und Stärke symbolisiert und

  14. Editorial: Theoriebildung in Mediendidaktik und Wissensmanagement

    Directory of Open Access Journals (Sweden)

    Michael Kerres

    2002-10-01

    , Kognitivismus und Konstruktivismus zur theoretischen Fundierung der Mediendidaktik. Er geht auf Missverständnisse und Probleme in diesem Zusammenhang ein. Als alternative Sichtweise stellen die Autoren eine Interpretation des Pragmatismus von John Dewey vor, der von der Lernsituation ausgeht und einen methodisch orientierten Ansatz anbietet. Damit wird letztlich eine stärkere Verbindung von Theorien der Mediendidaktik und Medienbildung angestrebt. Auch Stefan Krause und Rolf-Dieter Kortmann ziehen die Lerntheorien zur Diskussion der medienbasierten Wissensaneignung heran, sie legen ihren Schwerpunkt aber auf die Frage nach der aktuell diskutierten Problematik der Standardisierung bzw. Standardisierbarkeit von medial aufbereiteten Lerninhalten. Sie beschreiben, wie der Austausch von Inhalten perspektivisch nicht mehr über Datenformate, sondern durch Lernobjekte stattfindet, und diskutieren anhand eines Beispiels die - problematischen - Implikationen für die Mediendidaktik. Einen anderen Impuls gibt der Beitrag von Wolfgang Müskens und Isabel Müskens. Sie verstehen «Provokationen» als methodisches Element einer Didaktik internetgestützter Lernarrangements. «Provoziert» werden soll der Lernende durch einstellungskonträres Material, das letztlich zu einer höheren Individualisierung des Lernens und einer stärkeren Interaktion zwischen Lehrenden und Lernenden führen soll. Die theoretische Begründung solcher provokativen Elemente in einem didaktischen Konzept findet sich im Kompetenzbegriff und in der Systemtheorie, aber auch in psychologischen Ansätzen. In dem zweiten Teil dieser Ausgabe der Online-Zeitschrift geht es insbesondere um den Zusammenhang von Mediendidaktik und Wissensmanagement. Für Gabi Reinmann-Rothmeier handelt es sich bei Wissensmanagement und Mediendidaktik bislang um ein dialektisches Paar. Während Wissensmanagement eher ein Thema für die Betriebswirtschaft war, wurde die Mediendidaktik als eine (Teil-Disziplin der Medienpädagogik verstanden

  15. The use of CO 2 as an additive for ignition delay and pollutant control in CH 4 /air autoignition

    KAUST Repository

    Tingas, Efstathios Al.; Im, Hong G.; Kyritsis, Dimitrios C.; Goussis, Dimitris A.

    2017-01-01

    The effect of CO2 dilution on the adiabatic and isochoric autoignition of CH4/air mixtures is analyzed with Computational Singular Perturbation (CSP) algorithmic tools, with a particular emphasis on the determination of the features of the chemical

  16. An Ultralow Power Fast-Response Nano-TCD CH4 sensor for UAV Airborne Measurements, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — In this project, KWJ proposes to develop a low power, fast response, lightweight miniature CH4 measurement system based on KWJ nano-TCD sensor for airborne...

  17. Improved CRDS δ13C Stability Through New Calibration Application For CO2 And CH4

    Science.gov (United States)

    Rella, Chris; Arata, Caleb; Saad, Nabil; Leggett, Graham; Miles, Natasha; Richardson, Scott; Davis, Ken

    2015-04-01

    Stable carbon isotope ratio measurements of CO2 and CH4 provide valuable insight into global and regional sources and sinks of the two most important greenhouse gases. Methodologies based on Cavity Ring-Down Spectroscopy (CRDS) have been developed and are capable of delivering δ13C measurements with a precision better than 0.12 permil for CO2 and 0.4 permil for CH4 (1 hour window, 5 minute average). Here we present a method to further improve this measurement stability. We have developed a two-point calibration method which corrects for δ13C drift due to a dependence on carbon species concentration. This method calibrates for both carbon species concentration as well as δ13C. In addition, we further demonstrate that this added stability is especially valuable when using carbon isotope data in linear regression models such as Keeling plots, where even small amounts of error can be magnified to give inconclusive results. Furthermore, we show how this method is used to validate multiple instruments simultaneously and can be used to create the standard samples needed for field calibrations.

  18. Biochars as Potential Adsorbers of CH4, CO2 and H2S

    Directory of Open Access Journals (Sweden)

    Sumathi Sethupathi

    2017-01-01

    Full Text Available Methane gas, as one of the major biogases, is a potential source of renewable energy for power production. Biochar can be readily used to purify biogas contaminants such as H2S and CO2. This study assessed the adsorption of CH4, H2S, and CO2 onto four different types of biochars. The adsorption dynamics of biochars were investigated in a fixed-bed column, by determining the breakthrough curves and adsorption capacities of biochars. The physicochemical properties of biochars were considered to justify the adsorption performance. The results showed that CH4 was not adsorbed well by the subjected biochars whereas CO2 and H2S were successfully captured. The H2S and CO2 breakthrough capacity were related to both the surface adsorption and chemical reaction. The adsorption capacity was in the following order: perilla > soybean stover > Korean oak > Japanese oak biochars. The simultaneous adsorption also leads to a competition of sorption sites. Biochars are a promising material for the biogas purification industry.

  19. Northern peatland initiation lagged abrupt increases in deglacial atmospheric CH4.

    Science.gov (United States)

    Reyes, Alberto V; Cooke, Colin A

    2011-03-22

    Peatlands are a key component of the global carbon cycle. Chronologies of peatland initiation are typically based on compiled basal peat radiocarbon (14C) dates and frequency histograms of binned calibrated age ranges. However, such compilations are problematic because poor quality 14C dates are commonly included and because frequency histograms of binned age ranges introduce chronological artefacts that bias the record of peatland initiation. Using a published compilation of 274 basal 14C dates from Alaska as a case study, we show that nearly half the 14C dates are inappropriate for reconstructing peatland initiation, and that the temporal structure of peatland initiation is sensitive to sampling biases and treatment of calibrated 14C dates. We present revised chronologies of peatland initiation for Alaska and the circumpolar Arctic based on summed probability distributions of calibrated 14C dates. These revised chronologies reveal that northern peatland initiation lagged abrupt increases in atmospheric CH4 concentration at the start of the Bølling-Allerød interstadial (Termination 1A) and the end of the Younger Dryas chronozone (Termination 1B), suggesting that northern peatlands were not the primary drivers of the rapid increases in atmospheric CH4. Our results demonstrate that subtle methodological changes in the synthesis of basal 14C ages lead to substantially different interpretations of temporal trends in peatland initiation, with direct implications for the role of peatlands in the global carbon cycle.

  20. OEDGE modeling of the DIII-D double null (CH4)-C-13 puffing experiment

    International Nuclear Information System (INIS)

    Elder, J.D.; Wampler, W.R.; McLean, A.G.; Stangeby, P.C.; Allen, S.L.; Bray, B.D.; Brooks, N.H.; Leonard, A.W.; Unterberg, Ezekial A.; Watkins, J.G.

    2011-01-01

    Unbalanced double null ELMy H-mode configurations in DIII-D are used to simulate the situation in ITER high triangularity, burning plasma magnetic equilibria, where the second X-point lies close to the top of the vacuum vessel, creating a secondary divertor region at the upper blanket modules. The measured plasma conditions in the outer secondary divertor closely duplicated those projected for ITER. (CH4)-C-13 was injected into the secondary outer divertor to simulate sputtering there. The majority of the C-13 found was in the secondary outer divertor. This material migration pattern is radically different than that observed for main wall (CH4)-C-13 injections into single null configurations where the deposition is primarily at the inner divertor. The implications for tritium codeposition resulting from sputtering at the secondary divertor in ITER are significant since release of tritium from Be co-deposits at the main wall bake temperature for ITER, 240 degrees C, is incomplete. The principal features of the measured C-13 deposition pattern have been replicated by the OEDGE interpretive code.

  1. Burning Behaviour of High-Pressure CH4-H2-Air Mixtures

    Directory of Open Access Journals (Sweden)

    Jacopo D'Alessio

    2013-01-01

    Full Text Available Experimental characterization of the burning behavior of gaseous mixtures has been carried out, analyzing spherical expanding flames. Tests were performed in the Device for Hydrogen-Air Reaction Mode Analysis (DHARMA laboratory of Istituto Motori—CNR. Based on a high-pressure, constant-volume bomb, the activity is aimed at populating a systematic database on the burning properties of CH4, H2 and other species of interest, in conditions typical of internal combustion (i.c. engines and gas turbines. High-speed shadowgraph is used to record the flame growth, allowing to infer the laminar burning parameters and the flame stability properties. Mixtures of CH4, H2 and air have been analyzed at initial temperature 293÷305 K, initial pressure 3÷18 bar and equivalence ratio  = 1.0. The amount of H2 in the mixture was 0%, 20% and 30% (vol.. The effect of the initial pressure and of the Hydrogen content on the laminar burning velocity and the Markstein length has been evaluated: the relative weight and mutual interaction has been assessed of the two controlling parameters. Analysis has been carried out of the flame instability, expressed in terms of the critical radius for the onset of cellularity, as a function of the operating conditions.

  2. Serpentinization and the Formation of H2 and CH4 on Celestial Bodies (Planets, Moons, Comets).

    Science.gov (United States)

    Holm, N G; Oze, C; Mousis, O; Waite, J H; Guilbert-Lepoutre, A

    2015-07-01

    Serpentinization involves the hydrolysis and transformation of primary ferromagnesian minerals such as olivine ((Mg,Fe)2SiO4) and pyroxenes ((Mg,Fe)SiO3) to produce H2-rich fluids and a variety of secondary minerals over a wide range of environmental conditions. The continual and elevated production of H2 is capable of reducing carbon, thus initiating an inorganic pathway to produce organic compounds. The production of H2 and H2-dependent CH4 in serpentinization systems has received significant interdisciplinary interest, especially with regard to the abiotic synthesis of organic compounds and the origins and maintenance of life in Earth's lithosphere and elsewhere in the Universe. Here, serpentinization with an emphasis on the formation of H2 and CH4 are reviewed within the context of the mineralogy, temperature/pressure, and fluid/gas chemistry present in planetary environments. Whether deep in Earth's interior or in Kuiper Belt Objects in space, serpentinization is a feasible process to invoke as a means of producing astrobiologically indispensable H2 capable of reducing carbon to organic compounds.

  3. PENGARUH WAKTU KONTAK TERHADAP DAYA ADSORPSI KARBON AKTIF PADA PROSES PURIFIKASI CH4 DARI BIOGAS

    Directory of Open Access Journals (Sweden)

    Nani Harihastuti

    2016-11-01

    Full Text Available ABSTRAK Penggunaan biogas sebagai bahan bakar secara langsung sering menimbulkan permasalahan yaitu terjadi bau tidak sedap, peralatan logam  dan kompor cepat berkarat, dinding dapur terkikis  dan api sering  padam sendiri. Hal ini disebabkan dalam biogas selain metana (CH4 terkandung gas-gas lain H2S, NH3, CO2, H2 , CO dan uap air (H2O. Beberapa gas yang bersifat impurities ( H2S, NH3, CO2 dan uap air /H2O akan menurunkan nilai kalori dari biogas dan merugikan lingkungan dan kesehatan. Tujuan dari penelitian ini adalah untuk menghilangkan gas impurities dari biogas melalui proses purifikasi sehingga diperoleh biogas yang mempunyai nilai kalor tinggi dan ramah lingkungan.Metode yang dilakukan dengan proses adsorpsi menggunakan  adsorben karbon aktif dengan variabel waktu kontak, untuk mendapatkan daya adsorpsi yang optimum dari karbon aktif terhadap gas impurities yang ada dalam biogas. Hasil penelitian ini diperoleh data- data              penghilangan / reduksi gas  impuritis H2S mencapai 99,99% , dari 4200 ppm menjadi 0,22 ppm, penghilangan gas NH3 mencapai 94,96%, dari 12,7 ppm menjadi 0,65 ppm, penghilangan gas CO2 mencapai 77,48 %, dari 30, 77 % menjadi 6,93 %, penghilangan uap air (H2O mencapai 97,95%,  dari 0,584 mg/lt menjadi 0,012 mg/lt.Kenaikan konsentrasi methane (CH4 dari 38,2 % menjadi 84,12 %. Hasil purifikasi metana (CH4 dari biogas ini merupakan sumber energi  terbarukan yang aman dan  ramah lingkungan serta dapat di kembangkan lagi penerapannya di IKM tahu lainnya. Waktu jenuh adsorben karbon aktif diperoleh setelah  48 jam proses purifikasi berlangsung. Daya adsorpsi Karbon aktif optimum terhadap masing masing komponen gas impuritis adalah sebagai berikut terhadap H2S adalah  10,98 mg H2S/gram karbon aktif/menit, terhadap NH3  adalah 0,016 mg NH3/gram karbon aktif/menit, terhadap CO2 adalah 0,090mg CO2/gram karbon aktif/menit.Dampak yang terjadi bila biogas tidak dimanfaatkan dan dibiarkan terlepas ke

  4. Summary of LOX/CH4 Thruster Technology Development at NASA/MSFC

    Science.gov (United States)

    Greene, Sandra Elam

    2015-01-01

    In recent years, a variety of injectors for liquid oxygen (LOX) and methane (CH4) propellant systems have been designed, fabricated, and demonstrated with hot-fire testing at Marshall Space Flight Center (MSFC). Successful designs for liquid methane (LCH4) and gaseous methane (GCH4) have been developed. A variety of chambers, including a transpiration cooled design, along with uncooled ablatives and refractory metals, have also been hot-fire tested by MSFC for use with LOX/LCH4 injectors. Hot-fire testing has also demonstrated multiple ignition source options. Heat flux data for selected injectors has been gathered by testing with a calorimeter chamber. High performance and stable combustion have been demonstrated, along with designs for thrust levels ranging from 500 to 7,000 lbf. The newest LOX/CH4 injector and chamber developed by MSFC have been fabricated with additive manufacturing techniques and include unique design features to investigate regenerative cooling with methane. This low cost and versatile hardware offers a design for 4,000 lbf thrust and will be hot-fire tested at MSFC in 2015. Its design and operation can easily be scaled for use in systems with thrust levels up to 25,000 lbf.

  5. Inverse modelling of European CH4 emissions during 2006-2012 using different inverse models and reassessed atmospheric observations

    Science.gov (United States)

    Bergamaschi, Peter; Karstens, Ute; Manning, Alistair J.; Saunois, Marielle; Tsuruta, Aki; Berchet, Antoine; Vermeulen, Alexander T.; Arnold, Tim; Janssens-Maenhout, Greet; Hammer, Samuel; Levin, Ingeborg; Schmidt, Martina; Ramonet, Michel; Lopez, Morgan; Lavric, Jost; Aalto, Tuula; Chen, Huilin; Feist, Dietrich G.; Gerbig, Christoph; Haszpra, László; Hermansen, Ove; Manca, Giovanni; Moncrieff, John; Meinhardt, Frank; Necki, Jaroslaw; Galkowski, Michal; O'Doherty, Simon; Paramonova, Nina; Scheeren, Hubertus A.; Steinbacher, Martin; Dlugokencky, Ed

    2018-01-01

    We present inverse modelling (top down) estimates of European methane (CH4) emissions for 2006-2012 based on a new quality-controlled and harmonised in situ data set from 18 European atmospheric monitoring stations. We applied an ensemble of seven inverse models and performed four inversion experiments, investigating the impact of different sets of stations and the use of a priori information on emissions. The inverse models infer total CH4 emissions of 26.8 (20.2-29.7) Tg CH4 yr-1 (mean, 10th and 90th percentiles from all inversions) for the EU-28 for 2006-2012 from the four inversion experiments. For comparison, total anthropogenic CH4 emissions reported to UNFCCC (bottom up, based on statistical data and emissions factors) amount to only 21.3 Tg CH4 yr-1 (2006) to 18.8 Tg CH4 yr-1 (2012). A potential explanation for the higher range of top-down estimates compared to bottom-up inventories could be the contribution from natural sources, such as peatlands, wetlands, and wet soils. Based on seven different wetland inventories from the Wetland and Wetland CH4 Inter-comparison of Models Project (WETCHIMP), total wetland emissions of 4.3 (2.3-8.2) Tg CH4 yr-1 from the EU-28 are estimated. The hypothesis of significant natural emissions is supported by the finding that several inverse models yield significant seasonal cycles of derived CH4 emissions with maxima in summer, while anthropogenic CH4 emissions are assumed to have much lower seasonal variability. Taking into account the wetland emissions from the WETCHIMP ensemble, the top-down estimates are broadly consistent with the sum of anthropogenic and natural bottom-up inventories. However, the contribution of natural sources and their regional distribution remain rather uncertain. Furthermore, we investigate potential biases in the inverse models by comparison with regular aircraft profiles at four European sites and with vertical profiles obtained during the Infrastructure for Measurement of the European Carbon

  6. Implications for carbon processing beneath the Greenland Ice Sheet from dissolved CO2 and CH4 concentrations of subglacial discharge

    Science.gov (United States)

    Pain, A.; Martin, J.; Martin, E. E.

    2017-12-01

    Subglacial carbon processes are of increasing interest as warming induces ice melting and increases fluxes of glacial meltwater into proglacial rivers and the coastal ocean. Meltwater may serve as an atmospheric source or sink of carbon dioxide (CO2) or methane (CH4), depending on the magnitudes of subglacial organic carbon (OC) remineralization, which produces CO2 and CH4, and mineral weathering reactions, which consume CO2 but not CH4. We report wide variability in dissolved CO2 and CH4 concentrations at the beginning of the melt season (May-June 2017) between three sites draining land-terminating glaciers of the Greenland Ice Sheet. Two sites, located along the Watson River in western Greenland, drain the Isunnguata and Russell Glaciers and contained 1060 and 400 ppm CO2, respectively. In-situ CO2 flux measurements indicated that the Isunnguata was a source of atmospheric CO2, while the Russell was a sink. Both sites had elevated CH4 concentrations, at 325 and 25 ppm CH4, respectively, suggesting active anaerobic OC remineralization beneath the ice sheet. Dissolved CO2 and CH4 reached atmospheric equilibrium within 2.6 and 8.6 km downstream of Isunnguata and Russell discharge sites, respectively. These changes reflect rapid gas exchange with the atmosphere and/or CO2 consumption via instream mineral weathering. The third site, draining the Kiagtut Sermiat in southern Greenland, had about half atmospheric CO2 concentrations (250 ppm), but approximately atmospheric CH4 concentrations (2.1 ppm). Downstream CO2 flux measurements indicated ingassing of CO2 over the entire 10-km length of the proglacial river. CO2 undersaturation may be due to more readily weathered lithologies underlying the Kiagtut Sermiat compared to Watson River sites, but low CH4 concentrations also suggest limited contributions of CO2 and CH4 from OC remineralization. These results suggest that carbon processing beneath the Greenland Ice Sheet may be more variable than previously recognized

  7. Metal–organic frameworks for H2 and CH4 storage: insights on the pore geometry–sorption energetics relationship

    KAUST Repository

    Al Kordi, Mohamed; Belmabkhout, Youssef; Cairns, Amy; Eddaoudi, Mohamed

    2017-01-01

    This study aims to assess the possibility of improving H2 and CH4 binding affinity to the aromatic walls of a designed new Metal-Organic Framework (MOF) through simultaneous dispersive interactions. It is suggested here that desirable H2 and CH4 storage media at low pressures require narrow uniform pores associated with large surface area, a trade-off that is challenging to achieve.

  8. Organic chemistry of NH3 and HCN induced by an atmospheric abnormal glow discharge in N2-CH4 mixtures

    OpenAIRE

    2010-01-01

    Abstract The formation of the chemical products produced in an atmospheric glow discharge fed by a N2-CH4 gas mixture has been studied using Fourier Transform InfraRed (FTIR) and Optical Emission Spectrometry (OES). The measurements were carried out in a flowing regime at ambient temperature and pressure with CH4 concentrations ranging from 0.5% to 2%. In the recorded emission spectra the lines of the second positive system CN system and the first negative s...

  9. Quantifying the Variability of CH4 Emissions from Pan-Arctic Lakes with Lake Biogeochemical and Landscape Evolution Models

    Science.gov (United States)

    Tan, Z.; Zhuang, Q.

    2014-12-01

    Recent studies in the arctic and subarctic show that CH4 emissions from pan-arctic lakes are playing much more significant roles in the regional carbon cycling than previously estimated. Permafrost thawing due to pronounced warming at northern high latitudes affects lake morphology, changing its CH4 emissions. Thermokarst can enlarge the extent of artic lakes, exposing stable ancient carbon buried in the permafrost zone for degradation and changing a previously known carbon sink to a large carbon source. In some areas, the thawing of subarctic discontinuous and isolated permafrost can diminish thermokarst lakes. To date, few models have considered these important hydrological and biogeochemical processes to provide adequate estimation of CH4 emissions from these lakes. To fill this gap, we have developed a process-based climate-sensitive lake biogeochemical model and a landscape evolution model, which have been applied to quantify the state and variability of CH4 emissions from this freshwater system. Site-level experiments show the models are capable to capture the spatial and temporal variability of CH4 emissions from lakes across Siberia and Alaska. With the lake biogeochemical model solely, we estimate that the magnitude of CH4 emissions from lakes is 13.2 Tg yr-1 in the north of 60 ºN at present, which is on the same order of CH4 emissions from northern high-latitude wetlands. The maximum increment is 11.8 Tg CH4 yr-1 by the end of the 21st century when the worst warming scenario is assumed. We expect the landscape evolution model will improve the existing estimates.

  10. Flux and distribution of methane (CH4) in the Gunsan Basin of the southeastern Yellow Sea, off the Western Korea.

    Science.gov (United States)

    Lee, Jun-Ho; Woo, Han Jun; Son, Seung-Kyu; Kim, Moonkoo; Lee, Dong-Hun; Tsunogai, Urumu; Jeong, Kap-Sik

    2018-04-16

    The flux and distribution of methane (CH 4 ) was investigated in the seawater column at 14 stations in the Gunsan Basin, the southeastern part of Yellow Sea from 2013 to 2015. Here CH 4 is concentrated 2.4-4.7 (3.4 ± 0.7) nM in the surface and 2.5-7.4 (5.2 ± 1.7) nM in the bottom layer. The CH 4 saturation ratios ranged from 65.5% to 295.5% (162.6 ± 68.7), comprising the mean sea-to-air CH 4 flux of 3.8 to 25.3 (15.6 ± 5.5) µM m -2 d -1 . Methane concentration was largely different in the upper and the lower seawater layers that is separated by the thermocline of which depth is variable (20-60 m) depending on the time of sampling. The concentration of seawater dissolved CH 4 is high between the bottom surface of the thermocline layer and the sea floor. Generally it tends to decrease from the south-westernmost part of the basin toward the west coast of Korea. This distribution pattern of CH 4 seems to result from the CH 4 supply by decomposition of organic matters produced in the upper seawater layer that is superimposed by the larger supply from the underlying sediment layer especially beneath the thermocline. The latter is manifested by ubiquitous CH 4 seeps from the seafloor sediments.

  11. Metal–organic frameworks for H2 and CH4 storage: insights on the pore geometry–sorption energetics relationship

    KAUST Repository

    Al Kordi, Mohamed

    2017-02-09

    This study aims to assess the possibility of improving H2 and CH4 binding affinity to the aromatic walls of a designed new Metal-Organic Framework (MOF) through simultaneous dispersive interactions. It is suggested here that desirable H2 and CH4 storage media at low pressures require narrow uniform pores associated with large surface area, a trade-off that is challenging to achieve.

  12. Contribution of rice straw carbon to CH4 emission from rice paddies using 13C-enriched rice straw

    Science.gov (United States)

    Watanabe, Akira; Yoshida, Mariko; Kimura, Makoto

    1998-04-01

    It is generally recognized that the application of rice straw (RS) increases CH4 emission from rice paddies. To estimate the contribution of RS carbon to CH4 emission, a pot experiment was conducted using 13C-enriched RS. The percentage contributions of RS carbon to CH4 emission throughout the rice growth period were 10±1, 32±3, and 43±3% for the treatments with RS applied at the rates of 2, 4, and 6 g kg-1 soil, respectively. The increase in the rate of application of RS increased CH4 emission derived from both RS carbon and other carbon sources. The percentage contribution of RS carbon to CH4 emission was larger in the earlier period (maximum 96%) when the decomposition rate of RS was larger. After RS decomposition had slowed, CH4 emission derived from RS carbon decreased. However, the δ13C values of CH4 emitted from the pots with 13C-enriched RS applied at rates of 4 and 6 g kg-1 soil were significantly higher than those from the pots with natural RS until the harvesting stage. An increased atom-13C% of roots of rice plants growing in the pots with 6 g kg-1 of 13C-enriched RS at around the maximum tiller number stage and a decrease during the following 2 months suggested that rice plants assimilated RS carbon once and then released a portion of it. This supply of RS carbon from roots may be one of the sources of CH4 in the late period of rice growth.

  13. Effects of shifting growth stage and regulating temperature on seasonal variation of CH4 emission from rice

    Science.gov (United States)

    Watanabe, Akira; Yamada, Hiromi; Kimura, Makoto

    2001-09-01

    Seasonal variations in CH4 emission rates from rice paddies have been reported to have one or more maxima during the middle and late periods of rice growth. The factor affecting an appearance of CH4 emission maxima was examined in three types of pot experiments. In the experiment 1, four rice cultivars with difference in length of the period from transplanting to heading were transplanted on the same days. For the experiment 2, a cultivar was transplanted 4 times with interval of two weeks. In these experiments, the heading differed about a month between the earliest and latest treatments, respectively. However, shifting growth stage of rice plants did not shift the CH4 emission maxima, and the CH4 emission maxima often matched the maxima of daily mean air temperature. The effect of variation in temperature on CH4 emission rate was further investigated in the experiment 3 by placing the rice-planted pots under regulated temperature. Besides the first emission peak of CH4 attributable to rice straw (RS) carbon, three emission peaks corresponding to the peaks of air temperature were detected for the RS-applied pots placed outdoors. These three peaks were not observed or much less conspicuous for the RS-applied pots in a phytotron at 30°C. Temporal decreases in CH4 emission were detected both for the pots placed in the phytotron and outdoors just after the topdressing of (NH4)2SO4, which was considered to be a major cause of irregular disagreement between the variations in CH4 emission rates and in air temperature during the middle period of rice growth.

  14. Die Position des Rätoromanischen und seine Beziehungen zum Deutschen, Französischen und Italienischen

    Directory of Open Access Journals (Sweden)

    Roland Bauer

    2010-12-01

    Full Text Available Die Dialektometrie (DM ist eine induktive Methode, die es erlaubt, in Massendaten versteckte Oberflächenmuster und Tiefenstrukturen zu entdecken und mittels multipler, computergestützter Visualisierungen sicht- und damit auch interpretierbar zu machen. So bietet die DM u.a. eine Reihe von Möglichkeiten, Relationen zwischen den untersuchten Objekten (das sind in der Regel alle in einem Sprachatlas datenseitig abgebildeten Dialekte aufzudeckenund kartographisch in verschiedenster Form zu modellieren, um solcherart u.a. die Position einzelner Dialekte bzw. Geotypen im gesamten Beobachtungsraum näher bestimmen zu können. In diesem Zusammenhang hat es sich als durchaus nützlich erwiesen, zusätzliche Vergleichspunkte mit akrolektalen, also auf Standard- bzw. Hochsprachen bezogene Datenserien einzubauen. Im vorliegenden Fall konnten solcherart wechselseitige, je nach innerlinguistischer Ausrichtung der gewählten Corpora unterschiedlich ausgerichtete Einflüsse der Großsprachen Französisch und Italienisch auf die oberitalienische Dialektlandschaft sowie auf die drei Mitglieder der Sprachfamilie Rätoromanisch (nach Gartner 1883 bzw. ladino (nach Ascoli 1873 aufgezeigt werden. Dem Sprachkontakt aller genannten Idiome mit dem Deutschen konnte hingegen sowohl über die Visualisierung der relativen Präsenz von Germanismen mittels einer Dichtekarte als auch über eine gesonderte dialektometrische Ähnlichkeitskartierung nachgegangen werden, wobei interessante Einblicke in die von verschiedenen Substrat- und Adstratwirkungen abhängige, z.T. deutlich divergente Bewirtschaftung der rätoromanischen Teilräume gewonnen werden konnten.

  15. Climate change impact of livestock CH4 emission in India: Global temperature change potential (GTP) and surface temperature response.

    Science.gov (United States)

    Kumari, Shilpi; Hiloidhari, Moonmoon; Kumari, Nisha; Naik, S N; Dahiya, R P

    2018-01-01

    Two climate metrics, Global surface Temperature Change Potential (GTP) and the Absolute GTP (AGTP) are used for studying the global surface temperature impact of CH 4 emission from livestock in India. The impact on global surface temperature is estimated for 20 and 100 year time frames due to CH 4 emission. The results show that the CH 4 emission from livestock, worked out to 15.3 Tg in 2012. In terms of climate metrics GTP of livestock-related CH 4 emission in India in 2012 were 1030 Tg CO 2 e (GTP 20 ) and 62 Tg CO 2 e (GTP 100 ) at the 20 and 100 year time horizon, respectively. The study also illustrates that livestock-related CH 4 emissions in India can cause a surface temperature increase of up to 0.7mK and 0.036mK over the 20 and 100 year time periods, respectively. The surface temperature response to a year of Indian livestock emission peaks at 0.9mK in the year 2021 (9 years after the time of emission). The AGTP gives important information in terms of temperature change due to annual CH 4 emissions, which is useful when comparing policies that address multiple gases. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Effects of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence

    Science.gov (United States)

    Carmel E. Johnston,; Stephanie A. Ewing,; Harden, Jennifer W.; Ruth K. Varner,; Wickland, Kimberly P.; Koch, Joshua C.; Fuller, Christopher C.; Manies, Kristen L.; M. Torre Jorgenson,

    2014-01-01

    Permafrost soils store over half of global soil carbon (C), and northern frozen peatlands store about 10% of global permafrost C. With thaw, inundation of high latitude lowland peatlands typically increases the surface-atmosphere flux of methane (CH4), a potent greenhouse gas. To examine the effects of lowland permafrost thaw over millennial timescales, we measured carbon dioxide (CO2) and CH4 exchange along sites that constitute a ~1000 yr thaw chronosequence of thermokarst collapse bogs and adjacent fen locations at Innoko Flats Wildlife Refuge in western Alaska. Peak CH4exchange in July (123 ± 71 mg CH4–C m−2 d−1) was observed in features that have been thawed for 30 to 70 (peatlands, particularly those developed on poorly drained mineral substrates, are a key locus of elevated CH4 emission to the atmosphere that must be considered for a complete understanding of high latitude CH4 dynamics.

  17. CO2 and CH4 in sea ice from a subarctic fjord under influence of riverine input

    DEFF Research Database (Denmark)

    Crabeck, O.; Delille, B.; Thomas, D. N.

    2014-01-01

    We present CH4 concentration [CH4] and the partial pressure of CO2 (pCO2) in bulk sea ice from subarctic, land-fast sea ice in the Kapisillit fjord, Greenland. The bulk ice [CH4] ranged from 1.8 to 12.1 nmol L−1, which corresponds to a partial pressure range of 3 to 28 ppmv. This is markedly higher......-saturated compared to the atmosphere (390 ppmv). Our study adds to the few existing studies of CH4 and CO2 in sea ice and concludes that sub-arctic sea can be a sink for atmospheric CO2, while being a net source of CH4. Processes related to the freezing and melting of sea ice represents large unknowns...... to the exchange of CO2 but also CH4. It is therefore imperative to assess the consequences of these unknowns through further field campaigns and targeted research under other sea ice conditions at both hemispheres....

  18. Adsorption of CH4 on nitrogen- and boron-containing carbon models of coal predicted by density-functional theory

    Science.gov (United States)

    Liu, Xiao-Qiang; Xue, Ying; Tian, Zhi-Yue; Mo, Jing-Jing; Qiu, Nian-Xiang; Chu, Wei; Xie, He-Ping

    2013-11-01

    Graphene doped by nitrogen (N) and/or boron (B) is used to represent the surface models of coal with the structural heterogeneity. Through the density functional theory (DFT) calculations, the interactions between coalbed methane (CBM) and coal surfaces have been investigated. Several adsorption sites and orientations of methane (CH4) on graphenes were systematically considered. Our calculations predicted adsorption energies of CH4 on graphenes of up to -0.179 eV, with the strongest binding mode in which three hydrogen atoms of CH4 direct to graphene surface, observed for N-doped graphene, compared to the perfect (-0.154 eV), B-doped (-0.150 eV), and NB-doped graphenes (-0.170 eV). Doping N in graphene increases the adsorption energies of CH4, but slightly reduced binding is found when graphene is doped by B. Our results indicate that all of graphenes act as the role of a weak electron acceptor with respect to CH4. The interactions between CH4 and graphenes are the physical adsorption and slightly depend upon the adsorption sites on graphenes and the orientations of methane as well as the electronegativity of dopant atoms in graphene.

  19. Isotopomer analysis of production and consumption mechanisms of N2O and CH4 in an advanced wastewater treatment system.

    Science.gov (United States)

    Toyoda, Sakae; Suzuki, Yuuri; Hattori, Shohei; Yamada, Keita; Fujii, Ayako; Yoshida, Naohiro; Kouno, Rina; Murayama, Kouki; Shiomi, Hiroshi

    2011-02-01

    Wastewater treatment processes are believed to be anthropogenic sources of nitrous oxide (N(2)O) and methane (CH(4)). However, few studies have examined the mechanisms and controlling factors in production of these greenhouse gases in complex bacterial systems. To elucidate production and consumption mechanisms of N(2)O and CH(4) in microbial consortia during wastewater treatment and to characterize human waste sources, we measured their concentrations and isotopomer ratios (elemental isotope ratios and site-specific N isotope ratios in asymmetric molecules of NNO) in water and gas samples collected by an advanced treatment system in Tokyo. Although the estimated emissions of N(2)O and CH(4) from the system were found to be lower than those from the typical treatment systems reported before, water in biological reaction tanks was supersaturated with both gases. The concentration of N(2)O, produced mainly by nitrifier-denitrification as indicated by isotopomer ratios, was highest in the oxic tank (ca. 4000% saturation). The dissolved CH(4) concentration was highest in in-flow water (ca. 3000% saturation). It decreased gradually during treatment. Its carbon isotope ratio indicated that the decrease resulted from bacterial CH(4) oxidation and that microbial CH(4) production can occur in anaerobic and settling tanks.

  20. Influence of Meteorology and interrelationship with greenhouse gases (CO2 and CH4) at a suburban site of India

    Science.gov (United States)

    Sreenivas, Gaddamidi; Mahesh, Pathakoti; Subin, Jose; Lakshmi Kanchana, Asuri; Venkata Narasimha Rao, Pamaraju; Dadhwal, Vinay Kumar

    2016-03-01

    Atmospheric greenhouse gases (GHGs), such as carbon dioxide (CO2) and methane (CH4), are important climate forcing agents due to their significant impacts on the climate system. The present study brings out first continuous measurements of atmospheric GHGs using high-precision LGR-GGA over Shadnagar, a suburban site of Central India during the year 2014. The annual mean CO2 and CH4 over the study region are found to be 394 ± 2.92 and 1.92 ± 0.07 ppm (μ ± 1σ) respectively. CO2 and CH4 show a significant seasonal variation during the study period with maximum (minimum) CO2 observed during pre-monsoon (monsoon), while CH4 recorded the maximum during post-monsoon and minimum during monsoon. Irrespective of the seasons, consistent diurnal variations of these gases are observed. Influences of prevailing meteorology (air temperature, wind speed, wind direction, and relative humidity) on GHGs have also been investigated. CO2 and CH4 show a strong positive correlation during winter, pre-monsoon, monsoon, and post-monsoon with correlation coefficients (Rs) equal to 0.80, 0.80, 0.61, and 0.72 respectively, indicating a common anthropogenic source for these gases. Analysis of this study reveals the major sources for CO2 are soil respiration and anthropogenic emissions while vegetation acts as a main sink, whereas the major source and sink for CH4 are vegetation and presence of hydroxyl (OH) radicals.

  1. Disproportionation and thermochemical sulfate reduction reactions in S-H20-Ch4 and S-D2O-CH4 systems from 200 to 340 °C at elevated pressures

    Science.gov (United States)

    Yuan, Shunda; Chou, I-Ming; Burruss, Robert A.

    2013-01-01

    Elemental sulfur, as a transient intermediate compound, by-product, or catalyst, plays significant roles in thermochemical sulfate reduction (TSR) reactions. However, the mechanisms of the reactions in S-H2O-hydrocarbons systems are not clear. To improve our understanding of reaction mechanisms, we conducted a series of experiments between 200 and 340 °C for S-H2O-CH4, S-D2O-CH4, and S-CH4-1m ZnBr2 systems in fused silica capillary capsules (FSCC). After a heating period ranging from 24 to 2160 hours (hrs), the quenched samples were analyzed by Raman spectroscopy. Combined with the in situ Raman spectra collected at high temperatures and pressures in the S-H2O and S-H2O-CH4 systems, our results showed that (1) the disproportionation of sulfur in the S-H2O-CH4 system occurred at temperatures above 200 °C and produced H2S, SO42-, and possibly trace amount of HSO4-; (2) sulfate (and bisulfate), in the presence of sulfur, can be reduced by methane between 250 and 340 °C to produce CO2 and H2S, and these TSR temperatures are much closer to those of the natural system (2O-CH4 system may take place simultaneously, with TSR being favored at higher temperatures; and (4) in the system S-D2O-CH4, both TSR and the competitive disproportionation reactions occurred simultaneously at temperatures above 300 °C, but these reactions were very slow at lower temperatures. Our observation of methane reaction at 250 °C in a laboratory time scale suggests that, in a geologic time scale, methane may be destroyed by TSR reactions at temperatures > 200 °C that can be reached by deep drilling for hydrocarbon resources.

  2. Modeling Plasma-based CO2 and CH4 Conversion in Mixtures with N2, O2 and H2O: the Bigger Plasma Chemistry Picture

    KAUST Repository

    Wang, Weizong; Snoeckx, Ramses; Zhang, Xuming; Cha, Min; Bogaerts, Annemie

    2018-01-01

    performed regarding the single component gases, i.e. CO2 splitting and CH4 reforming, as well as for two component mixtures, i.e. dry reforming of methane (CO2/CH4), partial oxidation of methane (CH4/O2), artificial photosynthesis (CO2/H2O), CO2

  3. „Überholen ohne einzuholen“ Die Entwicklung von Technologien für übermorgen in Kernenergie und Mikroelektronik der DDR

    Science.gov (United States)

    Barkleit, Gerhard

    Dem nuklearen Patt zwischen Ostblock und westlichem Staatenbündnis ist es nach weitgehend übereinstimmender Auffassung von Politik und Wissenschaft zu danken, dass der "Kalte Krieg" in der zweiten Hälfte des 20. Jahrhunderts nicht zum weltumfassenden Flächenbrand eskalierte. An der raschen Herstellung dieses Patts waren zwei Dresdner Physiker maßgeblich beteiligt, deren einer im Manhattan-Projekt in den USA gearbeitet hatte und später in England der Spionage für die Sowjetunion und des Verrats des Know-how der Atombombe überführt wurde.

  4. Emotionen und Kontrollüberzeugungen beim komplexen Problemlösen : eine experimentelle Untersuchung anhand des computersimulierten Problemlöseszenarios FSYS 2.0

    OpenAIRE

    Spering, Miriam

    2001-01-01

    Diese Studie untersucht den Einfluss positiver und negativer Emotionen auf komplexes Problemlösen unter Berücksichtigung der Kompetenz- und Kontrollüberzeugungen als Traits. 74 studentische männliche und weibliche Probanden bearbeiteten das computersimulierte Szenario FSYS 2.0 (Wagener & Conrad, 1997), anhand dessen sich Aussagen sowohl über die Problemlösegüte als auch das Problemlöseverhalten (z.B. Informationsmanagement) treffen lassen. Emotionen wurden vor Beginn des Szenarios und nach de...

  5. MERLIN and MICROCARB : Preparation of 2 space missions for CO2 and CH4

    Science.gov (United States)

    Deniel, Carole; Millet, Bruno; Buisson, Francois; Pierangelo, Clémence; Jouglet, Denis; Bréon, Francois-Marie; Bousquet, Philippe; Chevallier, Fréderic; Crevoisier, Cyril; Ehret, Gerhard

    2017-04-01

    In collaboration with the research community and with close European partnerships, the French space agency, CNES is developing or co-developing two missions to be launched by 2021, MERLIN and MICROCARB, that are dedicated respectively to the observation of atmospheric concentrations of CH4 and CO2. Both missions are based on innovative instrumentation, microsatellites, specific algorithm inversion processes and calibration /validation approaches. Both will deliver very accurate weighted atmospheric column measurements over the globe for the two species that play a major role in climate change. The MERLIN (MEthane Remote sensing LIdar missioN) space segment consists of the new Myriade-Evolutions platform type (range of 400 kg) developed under CNES control, and of the first IPDA (Integrated Path Differential Absorption) LIDAR (Light Detecting And Ranging) instrument developed under DLR responsibility (Germany). The MERLIN satellite will be operated at an altitude of around 500 km, on a sun-synchronous orbit, either at 06:00 or 18:00 of the local time of the ascending node. The main science objective is to bring a significant improvement on the knowledge of CH4 emissions and sinks, derived from estimates of the CH4 column-averaged dry-mixing ratio at a 50 km horizontal resolution, with a precision of 1% and a challenging targeted accuracy of 0.2%. The MICROCARB mission is based on a compact grating spectrometer (around 60 kg) onboard a Myriade micro-satellite platform (170kg range). The satellite will fly on a sun-synchronous orbit at altitude around 650 km and at around 10h30 local time for the ascending node. The instrument will measure the reflected solar radiance in four spectral ranges in the infrared. Two bands with CO2 absorptions, at 1.6 µm (weak absorptions) and 2.0 µm (strong absorptions), allows retrieving the quantity of molecules of CO2. Two bands centered around 0.76 and 1.27 µm sample oxygen absorption lines and provide a proxy of the atmospheric

  6. Atmospheric modeling of Mars CH4 subsurface clathrates releases mimicking SAM and 2003 Earth-based detections

    Science.gov (United States)

    Pla-García, J.; Rafkin, S. C.

    2017-12-01

    The aim of this work is to establish the amount of mixing during all martian seasons to test whether CH4 releases inside or outside of Gale crater are consistent with MSL-SAM observations. Several modeling scenarios were configured, including instantaneous and steady releases, both inside and outside the crater. A simulation to mimic the 2003 Earth-based detections (Mumma et al. 2009 or M09) was also performed. In the instantaneous release inside Gale experiments, Ls270 was shown to be the faster mixing season when air within and outside the crater was well mixed: all tracer mass inside the crater is diluted after just 8 hours. The mixing of near surface crater air with the external environment in the rest of the year is potentially rapid but slower than Ls270.In the instantaneous release outside Gale (NW) experiment, in just 12 hours the CH4 that makes it to the MSL landing location is diluted by six orders of magnitude. The timescale of mixing in MRAMS experiments is on the order of 1 sol regardless of season. The duration of the CH4 peak observed by SAM is 100 sols. Therefore there is a steady release inside the crater, or there is a very large magnitude steady release outside the crater. In the steady release Gale experiments, CH4 flux rate from ground is 1.8 kg m-2 s-1 (derived from Gloesener et al. 2017 clathrates fluxes) and it is not predictive. In these experiments, 200 times lower CH4 values detected by SAM are modeled around MSL location. There are CH4 concentration variations of orders of magnitude depending on the hour, so timing of SAM measurements is important. With a larger (but further away) outside crater release area compared to inside, similar CH4 values around MSL are modeled, so distance to source is important. In the steady experiments mimicking M09 detection release area, only 12 times lower CH4 values detected by SAM are modeled around MSL. The highest value in the M09 modeled scenario (0.6 ppbv) is reached in Ls270. This value is the

  7. CH4 and N2O from mechanically turned windrow and vermicomposting systems following in-vessel pre-treatment

    International Nuclear Information System (INIS)

    Hobson, A.M.; Frederickson, J.; Dise, N.B.

    2005-01-01

    Methane (CH 4 ) and nitrous oxide (N 2 O) are included in the six greenhouse gases listed in the Kyoto protocol that require emission reduction. To meet reduced emission targets, governments need to first quantify their contribution to global warming. Composting has been identified as an important source of CH 4 and N 2 O. With increasing divergence of biodegradable waste from landfill into the composting sector, it is important to quantify emissions of CH 4 and N 2 O from all forms of composting and from all stages. This study focuses on the final phase of a two stage composting process and compares the generation and emission of CH 4 and N 2 O associated with two differing composting methods: mechanically turned windrow and vermicomposting. The first stage was in-vessel pre-treatment. Source-segregated household waste was first pre-composted for seven days using an in-vessel system. The second stage of composting involved forming half of the pre-composted material into a windrow and applying half to vermicomposting beds. The duration of this stage was 85 days and CH 4 and N 2 O emissions were monitored throughout for both systems. Waste samples were regularly subjected to respirometry analysis and both processes were found to be equally effective at stabilising the organic matter content. The mechanically turned windrow system was characterised by emissions of CH 4 and to a much lesser extent N 2 O. However, the vermicomposting system emitted significant fluxes of N 2 O and only trace amounts of CH 4 . In-vessel pre-treatment removed considerable amounts of available C and N prior to the second stage of composting. This had the effect of reducing emissions of CH 4 and N 2 O from the second stage compared to emissions from fresh waste found in other studies. The characteristics of each of the two composting processes are discussed in detail. Very different mechanisms for emission of CH 4 and N 2 O are proposed for each system. For the windrow system, development

  8. Germany and the nuclear non-proliferation; Current situation and prospects; Deutschland und die nukleare Nichtverbreitung; Zwischenbilanz und Ausblick

    Energy Technology Data Exchange (ETDEWEB)

    Preisinger, J.

    1993-07-01

    A summary is given of the consequences, both positive and negative, of international non-proliferation policy. The numerous, complex branches and connections of national measures and inter-stake agreements for the peaceful, controlled uses of nuclear technology and related military technologies are expertly described, and assessed on their effectiveness. Weak aspects of the nuclear non-proliferation regime are pointed out and past reforms are illustrated and assessed in the light of recent developments. The interests of the German Federal Republic from the centre of this analysis. The author shows that, after a certain hesitary, German diplomacy has now become active in the establishment of an international non-proliferation regime. He concludes that Germany should take a strong initiative role in maintaining a peaceful international nuclear order. (orig.) [Deutsch] Es wird ein Resuemee der bisherigen Erfolge und Misserfolge internationaler Nichtverbreitungspolitik gezogen. Die komplexen, vielfach veraestelten und verschachtelten nationalen Massnahmen und zwischenstaatlichen Vereinbarungen zur Ueberwachung und friedlichen Zweckbindung von Nukleartechnologie und militaerisch relevanten Anschlusstechnologien werden sachkundig erlaeutert und auf ihre Wirksamkeit ueberprueft. Schwachstellen des nuklearen Nichtverbreitungsregimes werden offengelegt, Reformschritte der vergangenen Jahre werden dargestellt und im Lichte der juengsten Entwicklungen bewertet. Dabei steht die Interessenlage der Bundesrepublik Deutschland im Zentrum der Analyse. Der Autor zeigt, dass die deutsche Diplomatie sich nach einer gewissen Zurueckhaltung schliesslich aktiv in die Gestaltung des internationalen Nichtverbreitungsregimes eingeschaltet hat. Er plaediert fuer eine kraftvolle Initiativrolle Deutschlands zur Erhaltung einer friedlichen internationalen Nuklearordnung. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Lohr, H.

    2001-07-01

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

  10. Deutschland und Polen: Kooperation trotz Differenzen; die Beziehungen zu Warschau sollten realpolitisch gedacht und verfolgt werden

    OpenAIRE

    Lang, Kai-Olaf

    2018-01-01

    Das Verhältnis zwischen Deutschland und Polen befindet sich in einer schwierigen Phase. Diverse bilaterale Streitpunkte sind dafür verantwortlich, dass sich die Beziehungen verschlechtert haben - darunter der mögliche Bau der Gaspipeline Nord Stream 2 durch die Ostsee, polnische Reparationsforderungen an die Adresse Berlins sowie europapolitischer Disput etwa um Aufnahmequoten für Flüchtlinge. Zudem hat Brüssel ein Verfahren nach Artikel 7 des EU-Vertrags eingeleitet - als Reaktion auf die in...

  11. Astronomical ephemerides, navigation and war. The astonishing cooperation of the ephemeris institutes of Germany, England, France and the USA during the Second World War based on documents in the archives of the Astronomisches Rechen-Institut. Edition of the documents. (German Title: Astronomische Ephemeriden, Navigation und Krieg. Die erstaunliche Zusammenarbeit der Ephemeriden-Institute von Deutschland, England, Frankreich und den USA im Zweiten Weltkrieg nach Dokumenten im Archiv des Astronomischen Rechen-Instituts. Edition der Dokumente.)

    Science.gov (United States)

    Wielen, Roland; Wielen, Ute

    During the whole period of the Second World War, England and the USA have exchanged astronomical ephemerides with Germany, even though these data were used for the navigation of warships and aircraft and were therefore of war importance. This astonishing fact is attested by numerous documents which survived in the archives of the Astronomisches Rechen-Institut (ARI). In Germany, the exchange was even explicitly authorized by the ministry which supervised the ARI (i.e. the Reichserziehungsminister). We present here examples of ephemerides for the Sun, the Moon, planets and stars, and explain the position determination by means of astronomical data. Ephemerides were published in almanacs which were computed and issued by special ephemeris institutes. We describe the agreements on the international exchange of ephemerides which were reached in peace times, and the continuation of this exchange during the war using intermediaries in neutral countries, first in the USA (U.S. Naval Observatory, USNO), and, from 1942 onwards, in Sweden (Stockholm Observatory). Involved persons were especially H. Spencer Jones (Astronomer Royal, Greenwich), J. F. Hellweg und W. J. Eckert (USNO), B. Lindblad (Sweden), and A. Kopff (ARI). All those relevant documents which are hold in the archives of the ARI, are described and annotated in detail. Scans of these documents are presented in a separate supplement.

  12. Rapid labelling of radiopharmaceuticals using 11CO2 and 11CH4

    International Nuclear Information System (INIS)

    Crouzel, C.

    1988-07-01

    In the past two decades, much effort has been devoted to the development of new molecules, labelled with β+ emitters usable for Positron Emission Tomography. Gaseous forms of 11 C ( 11 CO 2 or 11 CH 4 ) must be converted to a reactive form known as a ''radioactive precursor'': 11 C-methanol, 11 C-formaldehyde, 11 C-acetone, 11 C-phosgene, 11 C-diazomethane, 11 C-methylamine. These precursors are used to label radiopharmaceuticals. Few examples are given: 11 C-prazosin, 11 C-CGP 12177, 11 C-pindolol. Such synthesis procedures require strong initial activity (1.5 Ci). The processes are therefore remotely controlled or automated, and confined to shielded cells. Small laboratory robots have lately been introduced for this type of production

  13. Plasma discharge in N2 + CH4 at low pressures - Experimental results and applications to Titan

    Science.gov (United States)

    Thompson, W. Reid; Henry, Todd J.; Schwartz, Joel M.; Khare, B. N.; Sagan, Carl

    1991-01-01

    Results are reported from laboratory continuous-flow plasma-discharge experiments designed to simulate the formation of hydrocarbons and nitriles from N2 and CH4 in the atmosphere of Titan. Gas-chromatography and mass-spectrometry data were obtained in experiments lasting up to 100 h at temperature 295 K and pressure 17 or 0.24 mbar, modeling (1) cosmic-ray-induced processes in the Titan troposphere and (2) processes related to stratospheric aurorae excited by energetic electrons and ions from the Saturn magnetosphere, respectively. The results are presented in extensive tables and graphs, and the 0.24-mbar yields are incorporated into an eddy-mixing model to give stratospheric column abundances and mole fractions in good agreement with Voyager IRIS observations.

  14. Nitrogen Incorporation in CH4-N2 Photochemical Aerosol Produced by Far UV Irradiation

    Science.gov (United States)

    Trainer, Melissa G.; Jimenez, Jose L.; Yung, Yuk L.; Toon, Owen B.; Tolbert, Margaret A.

    2012-01-01

    Nitrile incorporation into Titan aerosol accompanying hydrocarbon chemistry is thought to be driven by extreme UV wavelengths (lambda irradiated gas. The aerosol mass greatly decreases when N2 is removed, indicating that N2 plays a major role in aerosol production. Because direct dissociation of N2 is highly improbable given the immeasurably low cross-section at the wavelengths studied, the chemical activation of N2 must occur via another pathway. Any chemical activation of N2 at wavelengths > 120 nm is presently unaccounted for in atmospheric photochemical models. We suggest that reaction with CH radicals produced from CH4 photolysis may provide a mechanism for incorporating N into the molecular structure of the aerosol. Further work is needed to understand the chemistry involved, as these processes may have significant implications for prebiotic chemistry on the early Earth and similar planets.

  15. Effect of CH4–Air Ratios on Gas Explosion Flame Microstructure and Propagation Behaviors

    Directory of Open Access Journals (Sweden)

    Ying Zhang

    2012-10-01

    Full Text Available To reveal the inner mechanism of gas explosion dynamic behavior affected by gas equivalent concentration, a high speed Schlieren image system and flow field measurement technology was applied to record the gas explosion flame propagation and flame structure transition. The results show that a flame front structure transition occurs, followed by a flame accelerating propagation process. The laminar to turbulence transition was the essential cause of the flame structure changes. The laminar flame propagation behavior was influenced mainly by gas expansion and fore-compressive wave effect, while the turbulent flame speed mostly depended on turbulence intensity, which also played an important role in peak value of the explosive pressure and flame speed. On the condition that the laminar-turbulent transition was easier to form, the conclusion was drawn that, the lowest CH4 concentration for maximum overpressure can be obtained, which was the essential reason why the ideal explosive concentration differs under different test conditions.

  16. Measurements and models of CO2 and CH4 Flux in the Baltimore/Washington area.

    Science.gov (United States)

    Dickerson, R. R.; Ren, X.; Salawitch, R. J.; Ahn, D.; Karion, A.; Shepson, P. B.; Whetstone, J. R.; Martin, C.

    2017-12-01

    Direct measurements of concentrations of pollutants such as CO2 and CH4 can be combined with wind fields to determine the flux of these species and to evaluate emissions inventories or models. The mass balance approach, assumng linear flow into and out of a volume set over a city, works best where wind fields are simplest. Over typical American east coast cities, upwind sources and complex circulation (e.g., the sea breeze) complicate such analyses. We will present findings from a coupled measurement and modeling project involving a network of surface-based tower measurements, aircraft observations, and remote sensing that constrain model calculations. Summer and winter scenarios are contrasted, and results help evaluate the emissions of short-lived pollutants. Determinations are compared to several emissions inventories and are being used to help States evaluate evaluate plans for pollution control.

  17. Measurements and Experimental Database Review for Laminar Flame Speed Premixed Ch4/Air Flames

    Science.gov (United States)

    Zubrilin, I. A.; Matveev, S. S.; Matveev, S. G.; Idrisov, D. V.

    2018-01-01

    Laminar flame speed (SL ) of CH4 was determined at atmospheric pressure and initial gas temperatures in range from 298 to 358 K. The heat flux method was employed to measure the flame speed in non-stretched flames. The kinetic mechanism GRI 3.0 [1] were used to simulate SL . The measurements were compared with available literature results. The data determined with the heat flux method agree with some previous burner measurements and disagree with the data from some vessel closed method and counterflow method. The GRI 3.0 mechanism was able to reproduce the present experiments. Laminar flame speed was determined at pressures range from of 1 to 20 atmospheres through mechanism GRI 3.0. Based on experimental data and calculations was obtained SL dependence on pressure and temperature. The resulting of dependence recommended use during the numerical simulation of methane combustion.

  18. Collision of H+ + CH4 at 30 eV: A simulation study

    International Nuclear Information System (INIS)

    Gao, Cong-Zhang; Wang, Jing; Zhang, Feng-Shou

    2013-01-01

    The process of proton impinging upon CH 4 molecule has been theoretically studied at 30 eV. The study is based on time-dependent local density approximation coupled with molecular dynamics model. The electronic density evolution, ionic motion, and the scattering angle are presented. We found that the mechanism of target ionization in present simulation is electron capture. The predicted rainbow angle is in good agreement with experiments and previous calculations. By comparing the scattering angle from present calculation with that from classical collision, we found that the nuclear stopping is dominant in small impact parameters, and the discrepancy in large impact parameters may be due to the neglect of electronic stopping in classical collision

  19. BOREAS TGB-5 CO2, CH4 and CO Chamber Flux Data Over the NSA

    Science.gov (United States)

    Burke, Roger; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor); Zepp, Richard

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-5) team collected a variety of trace gas concentration and flux measurements at several NSA sites. This data set contains carbon dioxide (CO2), methane (CH4), and carbon monoxide (CO) chamber flux measurements conducted in 1994 at upland forest sites that experienced stand-replacement fires. These measurements were acquired to understand the impact of fires on soil biogeochemistry and related changes in trace gas exchange in boreal forest soils. Relevant ancillary data, including data concerning the soil temperature, solar irradiance, and information from nearby un-burned control sites, are included to provide a basis for modeling the regional impacts of fire and climate changes on trace gas biogeochemistry. The data are provided in tabular ASCII files.

  20. Reduced gas seepages in ophiolitic complexes: Evidences for multiple origins of the H2-CH4-N2 gas mixtures

    Science.gov (United States)

    Vacquand, Christèle; Deville, Eric; Beaumont, Valérie; Guyot, François; Sissmann, Olivier; Pillot, Daniel; Arcilla, Carlo; Prinzhofer, Alain

    2018-02-01

    This paper proposes a comparative study of reduced gas seepages occurring in ultrabasic to basic rocks outcropping in ophiolitic complexes based on the study of seepages from Oman, the Philippines, Turkey and New Caledonia. This study is based on analyses of the gas chemical composition, noble gases contents, stable isotopes of carbon, hydrogen and nitrogen. These seepages are mostly made of mixtures of three main components which are H2, CH4 and N2 in various proportions. The relative contents of the three main gas components show 4 distinct types of gas mixtures (H2-rich, N2-rich, N2-H2-CH4 and H2-CH4). These types are interpreted as reflecting different zones of gas generation within or below the ophiolitic complexes. In the H2-rich type, associated noble gases display signatures close to the value of air. In addition to the atmospheric component, mantle and crustal contributions are present in the N2-rich, N2-H2-CH4 and H2-CH4 types. H2-bearing gases are either associated with ultra-basic (pH 10-12) spring waters or they seep directly in fracture systems from the ophiolitic rocks. In ophiolitic contexts, ultrabasic rocks provide an adequate environment with available Fe2+ and alkaline conditions that favor H2 production. CH4 is produced either directly by reaction of dissolved CO2 with basic-ultrabasic rocks during the serpentinization process or in a second step by H2-CO2 interaction. H2 is present in the gas when no more carbon is available in the system to generate CH4. The N2-rich type is notably associated with relatively high contents of crustal 4He and in this gas type N2 is interpreted as issued mainly from sediments located below the ophiolitic units.

  1. Sensitivity analysis of a new SWIR-channel measuring tropospheric CH 4 and CO from space

    Science.gov (United States)

    Jongma, Rienk T.; Gloudemans, Annemieke M. S.; Hoogeveen, Ruud W. M.; Aben, Ilse; de Vries, Johan; Escudero-Sanz, Isabel; van den Oord, Gijsbertus; Levelt, Pieternel F.

    2006-08-01

    In preparation for future atmospheric space missions a consortium of Dutch organizations is performing design studies on a nadir viewing grating-based imaging spectrometer using OMI and SCIAMACHY heritage. The spectrometer measures selected species (O 3, NO II, HCHO, H IIO, SO II, aerosols (optical depth, type and absorption index), CO and CH4) with sensitivity down to the Earth's surface, thus addressing science issues on air quality and climate. It includes 3 UV-VIS channels continuously covering the 270-490 nm range, a NIR-channel covering the 710-775 nm range, and a SWIR-channel covering the 2305-2385 nm range. This instrument concept is, named TROPOMI, part of the TRAQ-mission proposal to ESA in response to the Call for Earth Explorer Ideas 2005, and, named TROPI, part of the CAMEO-proposal prepared for the US NRC decadal study-call on Earth science and applications from space. The SWIR-channel is optional in the TROPOMI/TRAQ instrument and included as baseline in the TROPI/CAMEO instrument. This paper focuses on derivation of the instrument requirements of the SWIR-channel by presenting the results of retrieval studies. Synthetic detector spectra are generated by the combination of a forward model and an instrument simulator that includes the properties of state-of-the-art detector technology. The synthetic spectra are input to the CO and CH 4 IMLM retrieval algorithm originally developed for SCIAMACHY. The required accuracy of the Level-2 SWIR data products defines the main instrument parameters like spectral resolution and sampling, telescope aperture, detector temperature, and optical bench temperature. The impact of selected calibration and retrieval errors on the Level-2 products has been characterized. The current status of the SWIR-channel optical design with its demanding requirements on ground-pixel size, spectral resolution, and signal-to-noise ratio will be presented.

  2. Measurement of Kr-85 and Xe-133 as undisturbed tracers for the representing of atmospheric transport after disposal of radioactivity from nuclear facilities; Messungen von Kr-85 und Xe-133 als ungestoerte Tracer zur Darstellung atmosphaerischer Transportvorgaenge nach Freisetzung von Radioaktivitaet aus kerntechnischen Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    Frank, G.; Steinkopff, T. [Deutscher Wetterdienst (Germany); Salvamoser, J. [Institut fuer Angewandte Isotopen-, Gas- und Umweltuntersuchungen (IGU), Woerthsee (Germany)

    2016-07-01

    The Deutscher Wetterdienst (DWD, German Meteorological Service) operates since 1996 a sampling and measurement device for the radioactive rare gases Kr-85 and Xe-133 in Offenbach. These measurements are embedded in the German Measurement and Information System for Monitoring Environmental Radioactivity (Integriertes Mess- und Informationssystem zur Ueberwachung der Radioaktivitaet in der Umwelt, IMIS) [1]. In addition to these measurements the DWD is sampling rare gases in Potsdam and since 2014 in Trier in cooperation with the Bundesamt fuer Strahlenschutz (Federal Office for Radiation Protection, BfS). In the frame of the Global Atmosphere Watch (GAW)-program of the WMO the DWD operated a sampling station at the Zugspitze (Schneefernerhaus) from 1999 to 2005. This location at the Zugspitze is well suited for the observation of long distance transport of Kr-85 in the higher atmosphere. The DWD in Offenbach operates a complex analytical system for the measurement of Kr-85 and Xe-133 since 1998. This system consists of sampling with first enrichment, second enrichment, gas chromatographic separation and preparation of Krypton and Xenon and measurement of Kr-85 and Xe-133. Using the example Fukushima, it is shown, that the radioactive rare gases Kr-85 and Xe-133 are well undisturbed tracers for atmospheric transport in case of a nuclear accident or routine nuclear reprocessing plants. Measurements of Xe-133, I-131, Cs-137 and Kr-85 are correlated with source and atmospheric transport to the sampling sites at Offenbach and Potsdam.

  3. Carbon dynamics and CO2 and CH4 outgassing in the Mekong delta

    Science.gov (United States)

    Borges, Alberto V.; Abril, Gwenaël; Bouillon, Steven

    2018-02-01

    We report a data set of biogeochemical variables related to carbon cycling obtained in the three branches (Mỹ Tho, Hàm Luông, Cố Chiên) of the Mekong delta (Bến Tre province, Vietnam) in December 2003, April 2004, and October 2004. Both the inner estuary (upstream of the mouth) and the outer estuary (river plume) were sampled, as well as side channels. The values of the partial pressure of CO2 (pCO2) ranged between 232 and 4085 ppm, O2 saturation level (%O2) between 63 and 114 %, and CH4 between 2 and 2217 nmol L-1, within the ranges of values previously reported in temperate and tropical meso- and macro-tidal estuaries. Strong seasonal variations were observed. In the upper oligohaline estuary, low pCO2 (479-753 ppm) and high %O2 (98-106 %) values were observed in April 2004 most probably related to freshwater phytoplankton growth owing to low freshwater discharge (1400 m3 s-1) and increase in water residence time; during the two other sampling periods with a higher freshwater discharge (9300-17 900 m3 s-1), higher pCO2 (1895-2664 ppm) and lower %O2 (69-84 %) values were observed in the oligohaline part of the estuary. In October 2004, important phytoplankton growth occurred in the offshore part of the river plume as attested by changes in the contribution of particulate organic carbon (POC) to total suspended matter (TSM) (%POC) and the stable isotope composition of POC (δ13C-POC), possibly related to low TSM values (improvement of light conditions for phytoplankton development), leading to low pCO2 (232 ppm) and high %O2 (114 %) values. Water in the side channels in the Mekong delta was strongly impacted by inputs from the extensive shrimp farming ponds. The values of pCO2, CH4, %O2, and the stable isotope composition of dissolved inorganic carbon (δ13C-DIC) indicated intense organic matter degradation that was partly mediated by sulfate reduction in sediments, as revealed by the slope of total alkalinity (TA) and DIC covariations. The δ13C

  4. One year of continuous measurements of soil CH4 and CO2 fluxes in a Japanese cypress forest: Temporal and spatial variations associated with Asian monsoon rainfall

    OpenAIRE

    Sakabe, Ayaka; Kosugi, Yoshiko; Takahashi, Kenshi; Itoh, Masayuki; Kanazawa, Akito; Makita, Naoki; Ataka, Mioko

    2015-01-01

    We examined the effects of Asian monsoon rainfall on CH[4] absorption of water-unsaturated forest soil. We conducted a 1 year continuous measurement of soil CH[4] and CO[2] fluxes with automated chamber systems in three plots with different soil characteristics and water content to investigate how temporal variations in CH[4] fluxes vary with the soil environment. CH[4] absorption was reduced by the “Baiu” summer rainfall event and peaked during the subsequent hot, dry period. Although CH[4] ...

  5. Mycotic aneurysm of the superior mesenteric artery after septic embolism; Entwicklung eines mykotischen Aneurysmas der A. mesenterica superior nach septischer Embolie

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, F.; Dinkel, H.P. [Institut fuer Diagnostische Radiologie, Inselspital, Universitaetsklinik Bern (Switzerland)

    2002-07-01

    Mycotic aneurysms of the aorta and the visceral arteries are life-threatening diseases, due to potential rupture and organ or limb ischemia. They occur in endocarditis, immunodeficiency, bacteremia and fungemia, and have a poor prognosis.We report on a case of a 54-year-old male patient suffering from abdominal angina after mitral valve replacement for septic mycotic endocarditis. In presence of a mycotic-embolic occlusion of the left popliteal artery and multiple septic organ infarctions a mycotic aneurysm of the superior mesenteric artery was found in abdominal spiral-CT.Based on sequential spiral-CT examinations, this case demonstrates the development of a septic aneurysm of the superior mesenteric artery. (orig.) [German] Mykotische Aneurysmen der Aorta und ihrer Aeste stellen wegen Rupturgefahr und moeglicher Minderperfusion von Organen und Extremitaeten eine lebensgefaehrliche Erkrankung mit unguenstiger Prognose dar. Beguenstigende Faktoren sind geschwaechte Immunabwehr, Endokarditis, Bakteriaemie und Fungaemie.Wir berichten ueber einen 54-jaehrigen Patienten, der nach einem Mitralklappenersatz bei mykotischer Endokarditis zunehmende abdominelle Beschwerden im Sinne einer Angina abdominalis entwickelte. Die abdominelle Spiralcomputertomographie zeigte ein mykotisches Aneurysma der A. mesenterica superior. Daneben bestanden ein mykotischer Verschluss der linken A. poplitea und multiple septische Organinfarkte.Der Fall demonstriert anhand sequentieller Computertomographien eindrucksvoll die Entwicklung eines septischen Viszeralarterienaneurysmas. (orig.)

  6. Die Struktur der Handgesten im indischen Tanz nach dem „Nāṭya-Śāstra“ des Bharata (NŚBh)

    OpenAIRE

    Müller, Biliana

    2008-01-01

    In der vorliegenden Untersuchung wird eine Strukturanalyse der Gestensprache im indischen Tanz nach einem schriftlich vorliegenden Text vorgeschlagen – dem neunten Kapitel des ‚Nāṭya-Śāstra‘ eines legendären Autors namens Bharata. Der untersuchte Text ist Zeugnis für ein Zeichensystem, das über mehr als zwei Jahrtausende als Basis für die symbolische Interaktion auf dem indischen Subkontinent gedient hat und heute in zahlreichen Variationen präsent ist. Dieses Zeichensystem ist im semiotische...

  7. Greenhouse gas (CO2 and CH4) emissions from a high altitude hydroelectric reservoir in the tropics (Riogrande II, Colombia)

    Science.gov (United States)

    Guérin, Frédéric; Leon, Juan

    2015-04-01

    Tropical hydroelectric reservoirs are considered as very significant source of methane (CH4) and carbon dioxide (CO2), especially when flooding dense forest. We report emissions from the Rio Grande II Reservoir located at 2000 m.a.s.l. in the Colombian Andes. The dam was built at the confluence of the Rio Grande and Rio Chico in 1990. The reservoir has a surface of 12 km2, a maximum depth of 40m and a residence time of 2.5 month. Water quality (temperature, oxygen, pH, conductivity), nitrate, ammonium, dissolved and particulate organic carbon (DOC and POC), CO2 and CH4 were monitored bi-monthly during 1.5 year at 9 stations in the reservoir. Diffusive fluxes of CO2 and CH4 and CH4 ebullition were measured at 5 stations. The Rio grande II Reservoir is weakly stratified thermally with surface temperature ranging from 20 to 24°C and a constant bottom temperature of 18°C. The reservoir water column is well oxygenated at the surface and usually anoxic below 10m depth. At the stations close to the tributaries water inputs, the water column is well mixed and oxygenated from the surface to the bottom. As reported for other reservoirs located in "clear water" watersheds, the concentrations of nutrients are low (NO3-10 mmol m-2 d-1) were observed during the dry season. Close to the tributaries water inputs where the water column is well mixed, the average diffusive flux is 8 mmol m-2 d-1. CH4 ebullition was 3.5 mmol m-2 d-1 and no ebullition was observed for a water depth higher than 5m. The zone under the influence of the water inputs from tributaries represents 25% of the surface of the reservoir but contributed half of total CH4 emissions from the reservoir (29MgC month-1). Ebullition contributed only to 12% of total CH4 emissions over a year but it contributed up to 60% during the dry season. CH4 emissions from the Rio Grande Reservoir contributed 30% of the total GHG emissions (38GgCO2eq y-1). Overall, this study show that the majority of CH4 emissions from this

  8. Paradigmen und Textsorten lebensgeschichtlichen Erzählens

    Directory of Open Access Journals (Sweden)

    Neva Šlibar

    1995-12-01

    Full Text Available Denn im Grunde, heißt es da, ist Jugendfreundschaft um so sonderbarer, je älter man wird. Man ändert sich im Laufe solcher Jahre vom Scheitel bis zur Sohle und von den Härchen der Haut bis ins Herz, aber das Verhältnis zueinander bleibt merkwürdigerweise das gleiche und ändert sich sowenig wie die Beziehungen, die jeder einzelne Mensch zu den verschiedenen Herren pflegt, die er der Reihe nach mit Ich anspricht. Es kommt ja nicht darauf an, ob man so empfindet wie der kleine Knabe mit dickem Kopf und blondem Haar, der einst photographiert worden ist; nein, man kann im Grunde nicht einmal sagen, daß man dieses kleine, alberne, ichige Scheusal gern hat.

  9. Effects of coastal marsh conversion to shrimp aquaculture ponds on CH4 and N2O emissions

    Science.gov (United States)

    Yang, P.; Bastviken, D.; Lai, D. Y. F.; Jin, B. S.; Mou, X. J.; Tong, C.; Yao, Y. C.

    2017-12-01

    In this study, we compared the CH4 and N2O fluxes from a tidal brackish Cyperus malaccensis marsh ecosystem and nearby shrimp ponds, converted from C. malaccensis marsh in the last 3-4 years, in the Min River estuary of southeast China over the aquaculture period of the year. Significant differences in CH4 and N2O fluxes were observed in space (between brackish marsh and shrimp ponds) and in time (between sampling occasions that were distributed over the aquaculture period). CH4 fluxes from the shrimp ponds were on an average 10-fold higher than from the brackish marsh. N2O emissions, on the other hand, were lower from the shrimp pond (25% of the emissions from the brackish marsh). Accessory data indicates that these patterns were primarily linked to water level variability and temperature (all fluxes), sediment porewater sulfate concentrations (CH4 flux) and total nitrogen concentrations (N2O flux). Our research demonstrates that the coastal marsh ecosystem converted to aquaculture ponds considerably alter emissions of CH4 and N2O and provides input to the global discussion on how to account for emissions from various types of flooded land in greenhouse gas inventories.

  10. Glacial/interglacial wetland, biomass burning, and geologic methane emissions constrained by dual stable isotopic CH4 ice core records

    Science.gov (United States)

    Bock, Michael; Schmitt, Jochen; Beck, Jonas; Seth, Barbara; Chappellaz, Jérôme; Fischer, Hubertus

    2017-07-01

    Atmospheric methane (CH4) records reconstructed from polar ice cores represent an integrated view on processes predominantly taking place in the terrestrial biogeosphere. Here, we present dual stable isotopic methane records [δ13CH4 and δD(CH4)] from four Antarctic ice cores, which provide improved constraints on past changes in natural methane sources. Our isotope data show that tropical wetlands and seasonally inundated floodplains are most likely the controlling sources of atmospheric methane variations for the current and two older interglacials and their preceding glacial maxima. The changes in these sources are steered by variations in temperature, precipitation, and the water table as modulated by insolation, (local) sea level, and monsoon intensity. Based on our δD(CH4) constraint, it seems that geologic emissions of methane may play a steady but only minor role in atmospheric CH4 changes and that the glacial budget is not dominated by these sources. Superimposed on the glacial/interglacial variations is a marked difference in both isotope records, with systematically higher values during the last 25,000 y compared with older time periods. This shift cannot be explained by climatic changes. Rather, our isotopic methane budget points to a marked increase in fire activity, possibly caused by biome changes and accumulation of fuel related to the late Pleistocene megafauna extinction, which took place in the course of the last glacial.

  11. Adsorption of Dissolved Gases (CH4, CO2, H2, Noble Gases) by Water-Saturated Smectite Clay Minerals

    Science.gov (United States)

    Bourg, I. C.; Gadikota, G.; Dazas, B.

    2016-12-01

    Adsorption of dissolved gases by water-saturated clay minerals plays important roles in a range of fields. For example, gas adsorption in on clay minerals may significantly impact the formation of CH4 hydrates in fine-grained sediments, the behavior of CH4 in shale, CO2 leakage across caprocks of geologic CO2 sequestration sites, H2 leakage across engineered clay barriers of high-level radioactive waste repositories, and noble gas geochemistry reconstructions of hydrocarbon migration in the subsurface. Despite its importance, the adsorption of gases on clay minerals remains poorly understood. For example, some studies have suggested that clay surfaces promote the formation of CH4 hydrates, whereas others indicate that clay surfaces inhibit the formation of CH4 hydrates. Here, we present molecular dynamics (MD) simulations of the adsorption of a range of gases (CH4, CO2, H2, noble gases) on clay mineral surfaces. Our results indicate that the affinity of dissolved gases for clay mineral surfaces has a non-monotone dependence on the hydrated radius of the gas molecules. This non-monotone dependence arises from a combination of two effects: the polar nature of certain gas molecules (in particular, CO2) and the templating of interfacial water structure by the clay basal surface, which results in the presence of interfacial water "cages" of optimal size for intermediate-size gas molecules (such as Ne or Ar).

  12. A simple calculation algorithm to separate high-resolution CH4 flux measurements into ebullition and diffusion-derived components

    Science.gov (United States)

    Hoffmann, Mathias; Schulz-Hanke, Maximilian; Garcia Alba, Joana; Jurisch, Nicole; Hagemann, Ulrike; Sachs, Torsten; Sommer, Michael; Augustin, Jürgen

    2016-04-01

    Processes driving methane (CH4) emissions in wetland ecosystems are highly complex. Especially, the separation of CH4 emissions into ebullition and diffusion derived flux components, a perquisite for the mechanistic process understanding and identification of potential environmental driver is rather challenging. We present a simple calculation algorithm, based on an adaptive R-script, which separates open-water, closed chamber CH4 flux measurements into diffusion- and ebullition-derived components. Hence, flux component specific dynamics are revealed and potential environmental driver identified. Flux separation is based on a statistical approach, using ebullition related sudden concentration changes obtained during high resolution CH4 concentration measurements. By applying the lower and upper quartile ± the interquartile range (IQR) as a variable threshold, diffusion dominated periods of the flux measurement are filtered. Subsequently, flux calculation and separation is performed. The algorithm was verified in a laboratory experiment and tested under field conditions, using flux measurement data (July to September 2013) from a flooded, former fen grassland site. Erratic ebullition events contributed 46% to total CH4 emissions, which is comparable to values reported by literature. Additionally, a shift in the diurnal trend of diffusive fluxes throughout the measurement period, driven by the water temperature gradient, was revealed.

  13. On the question of whether particular demarcation and franchise agreements permitted by the German GWB Act are compatible with Art. 85 of the Treaty of Rome. Decision of the BGH (Federal High Court) of 11 March 1997 - KZR 2/96; Zur Vereinbarkeit der nach deutschem Recht vom Kartellverbot freigestellten Demarkations- und Konzessionsabsprachen mit Art. 85 EGV. BGH, Beschluss vom 11.3.1997 - KZR 2/96

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1997-11-01

    The BGH division for restraints of trade suspended the proceedings and submitted five questions to the European Court of Justice for preliminary ruling. The five questions as well as the reasons stated by the court are given as authentic texts. (CB) [Deutsch] Der Kartellsenat des BGH hat das Verfahren ausgesetzt und dem EuGH fuenf Fragen zur Vorentscheidung vorgelegt. Die Fragen und die vollstaendige Begruendung werden im vollen Wortlaut angegeben. (CB)

  14. Das Usutu-Virus als Ursache von Massensterben bei Amseln Turdus merula und anderen Vogelarten in Europa: Erfahrungen aus fünf Ausbrüchen zwischen 2001 und 2011

    OpenAIRE

    Bosch, Stefan; Schmidt-Chanasit, Jonas; Fiedler, Wolfgang

    2012-01-01

    Das Usutu-Virus (USUV) ist ein durch Stechmücken der Gattung Culex übertragenes Flavivirus. Es wurde wahrscheinlich durch Zugvögel oder Stechmücken nach Europa eingeschleppt und hat sich inzwischen dauerhaft in der einheimischen Stechmücken-und Vogelfauna etabliert. Seit seinem Erstnachweis 2001 in Österreich hat das USUV fünf größere Ausbrüche mit USUV-assoziierten Vogelsterben, vor allem unter Amseln und in Volieren gehaltenen Eulen, sowie vermutlich kleinere Ausbrüche ohne augenfälliges Vo...

  15. Study of the daily and seasonal atmospheric CH4 mixing ratio variability in a rural Spanish region using 222Rn tracer

    Science.gov (United States)

    Grossi, Claudia; Vogel, Felix R.; Curcoll, Roger; Àgueda, Alba; Vargas, Arturo; Rodó, Xavier; Morguí, Josep-Anton

    2018-04-01

    The ClimaDat station at Gredos (GIC3) has been continuously measuring atmospheric (dry air) mixing ratios of carbon dioxide (CO2) and methane (CH4), as well as meteorological parameters, since November 2012. In this study we investigate the atmospheric variability of CH4 mixing ratios between 2013 and 2015 at GIC3 with the help of co-located observations of 222Rn concentrations, modelled 222Rn fluxes and modelled planetary boundary layer heights (PBLHs). Both daily and seasonal changes in atmospheric CH4 can be better understood with the help of atmospheric concentrations of 222Rn (and the corresponding fluxes). On a daily timescale, the variation in the PBLH is the main driver for 222Rn and CH4 variability while, on monthly timescales, their atmospheric variability seems to depend on emission changes. To understand (changing) CH4 emissions, nocturnal fluxes of CH4 were estimated using two methods: the radon tracer method (RTM) and a method based on the EDGARv4.2 bottom-up emission inventory, both using FLEXPARTv9.0.2 footprints. The mean value of RTM-based methane fluxes (FR_CH4) is 0.11 mg CH4 m-2 h-1 with a standard deviation of 0.09 or 0.29 mg CH4 m-2 h-1 with a standard deviation of 0.23 mg CH4 m-2 h-1 when using a rescaled 222Rn map (FR_CH4_rescale). For our observational period, the mean value of methane fluxes based on the bottom-up inventory (FE_CH4) is 0.33 mg CH4 m-2 h-1 with a standard deviation of 0.08 mg CH4 m-2 h-1. Monthly CH4 fluxes based on RTM (both FR_CH4 and FR_CH4_rescale) show a seasonality which is not observed for monthly FE_CH4 fluxes. During January-May, RTM-based CH4 fluxes present mean values 25 % lower than during June-December. This seasonal increase in methane fluxes calculated by RTM for the GIC3 area appears to coincide with the arrival of transhumant livestock at GIC3 in the second half of the year.

  16. Safety in pipeline systems. Prevention of pressure shocks and cavitation shocks; Sichere Rohrleitungssysteme. Vermeidung von Druckstoessen und Kavitationsschlaegen

    Energy Technology Data Exchange (ETDEWEB)

    Prasser, H.-M. [Forschungszentrum Rossendorf, Dresden (Germany); Dudlik, Andreas; Schoenfeld, Sri Budi Handajani; Apostolidis, Alexander; Schlueter, Stefan [Fraunhofer-Institut UMSICHT, Oberhausen (Germany)

    2002-06-01

    The Fraunhofer institute UMSICHT, Oberhausen, and Rossendorf research centre FZR investigated the causes and consequences of pressure shocks and cavitation shocks and ways to prevent them. The experimental set-up and software tools were made available. New methods for preventing pressure shocks and cavitation shocks were developed, and armatures were developed on this basis which are also suited for retrofitting. [German] In Rohrleitungssystemen koennen durch instationaere Stroemungsvorgaenge gefaehrliche Betriebsbedingungen entstehen, die infolge von mehrfach erhoehtem Systemdruck und von Lasteintraegen in Halterungen Mensch und Umwelt erheblich schaedigen. Je nach Industriebranche koennen unterschiedliche betriebsbedingte Ursachen zu sog. Druckstoessen, Kavitations- und Kondensationsschlaegen fuehren, z.B. Kontaktkondensation von Dampf und Wasser oder ploetzliche Aenderung der Fluessigkeitsgeschwindigkeit. Das Fraunhofer-Institut UMSICHT in Oberhausen und das Forschungszentrum Rossendorf FZR untersuchen Ursachen, Folgen und Moeglichkeiten zur Vermeidung von Druckstoessen und Kavitationsschlaegen. Hierzu stehen Versuchsanlagen unterschiedlichen Massstabs sowie Softwaretools zur Verfuegung. Aus den Forschungsergebnissen wurden neue Methoden zur Vermeidung von Druckstoessen und Kavitationsschlaegen entwickelt. Hierbei werden neue oder vorhandene Absperrarmaturen mit einem hydraulischen Bremssystem ausgeruestet und mit einer Rueckschlagklappe kombiniert angeordnet. Das System gilt auch fuer bereits existierende Anlagen als besonders geeignet, da es keine Hilfsenergie benoetigt und sich an Aenderungen der Systemparameter Druck und Fliessgeschwindigkeit selbststaendig anpasst. (orig.)

  17. Investigating CH4 production in an oxic plant-soil system -a new approach combining isotopic labelling (13C) and inhibitors

    Science.gov (United States)

    Lenhart, Katharina; Keppler, Frank

    2017-04-01

    Typically, aerated soil are net sinks of atmospheric methane (CH4), being highest in native ecosystems (pristine forests > managed forests > grasslands > crop fields). However, this does not exclude a simultaneous endogenic CH4 production in the plant-soil system, which cannot be detected simply via CH4 flux measurements. Methanogenic archaea producing CH4 under anoxic conditions were thought to be the only biotic source of CH4 in the soil. However, until recently a non-archaeal pathway of CH4 formation is known where CH4 is produced under oxic conditions in plants (Keppler et al. 2006) and fungi (Lenhart et al. 2012). Additionally, abiotic formation of CH4 from soil organic matter was reported (Jugold et al. 2012) and may be ubiquitous in terrestrial ecosystems. The major goal of this project was to determine soil endogenic CH4 sources and to estimate their contribution to the endogenic CH4 production. Especially the effect of plants and fungi on soil CH4 production was investigated. Therefore, a series of experiments was carried out on field fresh soil collected in a grassland and a forest ecosystem under controlled laboratory conditions. By combining selective inhibitors and 13C labelling, CH4 production rates of several CH4 sources were quantified. The major difficulty was to detect the comparatively small flux of CH4 production against the background of the high CH4 consumption rates due to methanotrophic bacteria. Therefore, we supplemented bare soil and soil with vegetation with selective inhibitors and 13C labelled substrates in a closed chamber system. In a first step, CH4 production was determined by the inhibition of CH4 oxidizing bacteria with Difluoromethane (DFM, 2ml l-1). In the following, a 13C labelled substrate (either CO2, Acetate, or Methionine -S-CH3 labelled) was added in combination with a specific inhibitor -either for archaeal methanogenesis (Bromoethanesulfonate), bacteria (Streptomycin), or fungi (Captan, Cycloheximide). Gas samples were

  18. Carbonate control of H2 and CH4 production in serpentinization systems at elevated P-Ts

    Science.gov (United States)

    Jones, L. Camille; Rosenbauer, Robert; Goldsmith, Jonas I.; Oze, Christopher

    2010-01-01

    Serpentinization of forsteritic olivine results in the inorganic synthesis of molecular hydrogen (H2) in ultramafic hydrothermal systems (e.g., mid-ocean ridge and forearc environments). Inorganic carbon in those hydrothermal systems may react with H2 to produce methane (CH4) and other hydrocarbons or react with dissolved metal ions to form carbonate minerals. Here, we report serpentinization experiments at 200°C and 300 bar demonstrating Fe2+ being incorporated into carbonates more rapidly than Fe2+ oxidation (and concomitant H2 formation) leading to diminished yields of H2 and H2-dependent CH4. In addition, carbonate formation is temporally fast in carbonate oversaturated fluids. Our results demonstrate that carbonate chemistry ultimately modulates the abiotic synthesis of both H2 and CH4 in hydrothermal ultramafic systems and that ultramafic systems present great potential for CO2-mineral sequestration.

  19. Thermal effects of an ICL-based mid-infrared CH4 sensor within a wide atmospheric temperature range

    Science.gov (United States)

    Ye, Weilin; Zheng, Chuantao; Sanchez, Nancy P.; Girija, Aswathy V.; He, Qixin; Zheng, Huadan; Griffin, Robert J.; Tittel, Frank K.

    2018-03-01

    The thermal effects of an interband cascade laser (ICL) based mid-infrared methane (CH4) sensor that uses long-path absorption spectroscopy were studied. The sensor performance in the laboratory at a constant temperature of ∼25 °C was measured for 5 h and its Allan deviation was ∼2 ppbv with a 1 s averaging time. A LabVIEW-based simulation program was developed to study thermal effects on infrared absorption and a temperature compensation technique was developed to minimize these effects. An environmental test chamber was employed to investigate the thermal effects that occur in the sensor system with variation of the test chamber temperature between 10 and 30 °C. The thermal response of the sensor in a laboratory setting was observed using a 2.1 ppm CH4 standard gas sample. Indoor/outdoor CH4 measurements were conducted to evaluate the sensor performance within a wide atmospheric temperature range.

  20. Bio-refinery system of DME or CH4 production from black liquor gasification in pulp mills.

    Science.gov (United States)

    Naqvi, M; Yan, J; Fröling, M

    2010-02-01

    There is great interest in developing black liquor gasification technology over recent years for efficient recovery of bio-based residues in chemical pulp mills. Two potential technologies of producing dimethyl ether (DME) and methane (CH(4)) as alternative fuels from black liquor gasification integrated with the pulp mill have been studied and compared in this paper. System performance is evaluated based on: (i) comparison with the reference pulp mill, (ii) fuel to product efficiency (FTPE) and (iii) biofuel production potential (BPP). The comparison with the reference mill shows that black liquor to biofuel route will add a highly significant new revenue stream to the pulp industry. The results indicate a large potential of DME and CH(4) production globally in terms of black liquor availability. BPP and FTPE of CH(4) production is higher than DME due to more optimized integration with the pulping process and elimination of evaporation unit in the pulp mill.

  1. Seasonal CH4 and N2O emissions and plant growth characteristics of several cultivars in direct seeded rice systems

    Science.gov (United States)

    Simmonds, M.; Anders, M. M.; Adviento-Borbe, M. A.; Van Kessel, C.; McClung, A.; Linquist, B.

    2014-12-01

    Understanding cultivar effects on field greenhouse gas (GHG) emissions in rice (Oryza sativa L.) systems is needed to improve the accuracy of predictive models used for estimating GHG emissions, and to determine to what extent choice of cultivar may have on GHG mitigation. We compared CH4 and N2O emissions, global warming potential (GWP = N2O + CH4), yield-scaled GWP (GWPY = GWP Mg-1 grain), and plant growth characteristics of 8 cultivars within 4 study sites in California and Arkansas. Seasonal CH4 emissions differed between cultivars by a factor of 2.1 and 1.3 at one California and one Arkansas site, respectively. Nitrous oxide emissions were negligible, comprised food security.

  2. Predictive parameters of infectiologic complications in patients after TIPSS; Praediktive Parameter infektiologischer Komplikationen bei Patienten nach TIPSS-Anlage

    Energy Technology Data Exchange (ETDEWEB)

    Cohnen, M.; Saleh, A.; Moedder, U. [Institut fuer Diagnostische Radiologie, Universitaetsklinikum Duesseldorf (Germany); Luethen, R.; Bode, J.; Haeussinger, D. [Klinik fuer Gastroenterologie, Hepatologie und Infektiologie, Universitaetsklinikum Duesseldorf (Germany); Daeubener, W. [Institut fuer Mikrobiologie und Virologie, Universitaetsklinikum Duesseldorf (Germany)

    2003-02-01

    Aim To define predictive parameters of a complicated clinical course after the TIPSS procedure. Blood cultures were drawn prospectively in 41 patients from a central line and from the portal venous blood before stent placement as well as from the central line 20 min after intervention. C-reactive proteine (CRP) (mg/dl) and white blood cell count (WBC,/{mu}l) on the day of TIPSS-procedure (d0), the first (d1) and seven (d7) days after TIPSS were compared in patients with a complicated clinical course (spontaneous bacterial peritonitis, pneumonia, sepsis; group I) to patients without clinical complications (group II) Group I showed a significant increase in CRP (d0: 1.8{+-}1.0; d1: 3.2{+-}1.5; d7: 4.3{+-}3.2), and white blood cell count (d0: 7700{+-}2600; d1: 10800{+-}2800; d7: 7500{+-}1800) on the first day after TIPSS-procedure in comparison to group II (CRP: d0: 1.6{+-}0.6; d1: 1.8{+-}1.0; d7: 1.9{+-}0.6. WBC: d0: 6900{+-}1500; d1: 8000{+-}1600; d7: 7600{+-}1400).Microbiological analysis showed in 12% skin or oral flora in the last sample. The course of CRP and WBC-count during the first week after TIPSS procedure may indicate patients with a potential risk of a complicated clinical course. (orig.) [German] Fragestellung Definition praediktiver Parameter infektiologischer Komplikationen bei Patienten nach TIPSS-Anlage.Methodik Bei 41 Patienten wurden Blutproben prospektiv vor intrahepatischer Stentanlage zentralvenoes und portalvenoes sowie 20 min postinterventionell erneut zentralvenoes entnommen und mikrobiologisch analysiert. C-reaktives Protein (CRP) (mg/dl) und Leukozytenzahl (/{mu}l) wurden am Interventionstag (d0), am 1. (d1) sowie 7 Tage (d7) postinterventionell bestimmt. Patienten mit kompliziertem Verlauf (spontane bakterielle Peritonitis,Pneumonie, Sepsis; Gruppe 1) wurden von Patienten ohne klinische Komplikationen (Gruppe 2) unterschieden.Ergebnisse Gruppe 1 wies einen signifikanten Anstieg des CRP (d0: 1,8{+-}1,0; d1: 3,2{+-}1,5; d7: 4,3{+-}3,2) und

  3. Site specific comparison of H2, CH4 and compressed air energy storage in porous formations

    Science.gov (United States)

    Tilmann Pfeiffer, Wolf; Wang, Bo; Bauer, Sebastian

    2016-04-01

    The supply of energy from renewable sources like wind or solar power is subject to fluctuations determined by the climatic and weather conditions, and shortage periods can be expected on the order of days to weeks. Energy storage is thus required if renewable energy dominates the total energy production and has to compensate the shortages. Porous formations in the subsurface could provide large storage capacities for various energy carriers, such as hydrogen (H2), synthetic methane (CH4) or compressed air (CAES). All three energy storage options have similar requirements regarding the storage site characteristics and consequently compete for suitable subsurface structures. The aim of this work is to compare the individual storage methods for an individual storage site regarding the storage capacity as well as the achievable delivery rates. This objective is pursued using numerical simulation of the individual storage operations. In a first step, a synthetic anticline with a radius of 4 km, a drop of 900 m and a formation thickness of 20 m is used to compare the individual storage methods. The storage operations are carried out using -depending on the energy carrier- 5 to 13 wells placed in the top of the structure. A homogeneous parameter distribution is assumed with permeability, porosity and residual water saturation being 500 mD, 0.35 and 0.2, respectively. N2 is used as a cushion gas in the H2 storage simulations. In case of compressed air energy storage, a high discharge rate of 400 kg/s equating to 28.8 mio. m³/d at surface conditions is required to produce 320 MW of power. Using 13 wells the storage is capable of supplying the specified gas flow rate for a period of 31 hours. Two cases using 5 and 9 wells were simulated for both the H2 and the CH4 storage operation. The target withdrawal rates of 1 mio. sm³/d are maintained for the whole extraction period of one week in all simulations. However, the power output differs with the 5 well scenario producing

  4. Mädchenschulen: Dramatisierung oder Entdramatisierung von Geschlecht? Eine verschränkende Darstellung vertiefter quantitativer und qualitativer empirischer Analysen zur 'Wirkungsweise' der Geschlechtersegregation

    OpenAIRE

    Schurt, Verena

    2011-01-01

    Wie die Ergebnisse aktueller Bildungsstudien verdeutlichen, werden die Unterschiede zwischen Mädchen und Jungen zwar insbesondere in Bezug auf den formalen Schulerfolg immer geringer, allerdings bestehen nach wie vor bereichsspezifische Geschlechterdifferenzen, die ihren Niederschlag u.a. in der (ökonomisch und sozial) meist ungünstigeren Situation von Frauen im Erwerbsleben finden. Vor diesem Hintergrund stellt sich die Ausgangsfrage, ob monoedukative Schulen Chancen für eine Nivellierung ge...

  5. Untersuchung der Abgaswärmeübertragung und der Dampfstrahlverdichtung zur Bewertung von Dampfstrahlkälteanlagen als Ladeluftkühler aufgeladener Ottomotoren

    OpenAIRE

    Zegenhagen, Mark Tobias

    2015-01-01

    In der vorliegenden Arbeit werden die Eigenschaften und das Potential eines mit Abgaswärme angetriebenen Dampfstrahlkälteprozesses mit dem Kältemittel R134a zur weiteren Kühlung der Ladeluft nach der konventionellen Ladeluftkühlung bei aufgeladenen Ottomotoren im Kraftfahrzeug analysiert, indem der Abgaswärmeübertrager sowie der Dampfstrahlverdichter als Kernkomponenten des Kälteprozesses getrennt voneinander experimentell und mit Simulationsmodellen theoretisch untersucht werden. Die vom ...

  6. Hydrogenation of organic matter as a terminal electron sink sustains high CO 2 :CH 4 production ratios during anaerobic decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Rachel M.; Tfaily, Malak M.; Rich, Virginia I.; Keller, Jason K.; Bridgham, Scott D.; Zalman, Cassandra Medvedeff; Meredith, Laura; Hanson, Paul J.; Hines, Mark; Pfeifer-Meister, Laurel; Saleska, Scott R.; Crill, Patrick; Cooper, William T.; Chanton, Jeff P.; Kostka, Joel E.

    2017-10-01

    Once inorganic electron acceptors are depleted, organic matter in anoxic environments decomposes by hydrolysis, fermentation, and methanogenesis, requiring syntrophic interactions between microorganisms to achieve energetic favorability. In this classic anaerobic food chain, methanogenesis represents the terminal electron accepting (TEA) process, ultimately producing equimolar CO2 and CH4 for each molecule of organic matter degraded. However, CO2:CH4 production in Sphagnum-derived, mineral-poor, cellulosic peat often substantially exceeds this 1:1 ratio, even in the absence of measureable inorganic TEAs. Since the oxidation state of C in both cellulose-derived organic matter and acetate is 0, and CO2 has an oxidation state of +4, if CH4 (oxidation state -4) is not produced in equal ratio, then some other compound(s) must balance CO2 production by receiving 4 electrons. Here we present evidence for ubiquitous hydrogenation of diverse unsaturated compounds that appear to serve as organic TEAs in peat, thereby providing the necessary electron balance to sustain CO2:CH4 >1. While organic electron acceptors have previously been proposed to drive microbial respiration of organic matter through the reversible reduction of quinone moieties, the hydrogenation mechanism that we propose, by contrast, reduces C-C double bonds in organic matter thereby serving as 1) a terminal electron sink, 2) a mechanism for degrading complex unsaturated organic molecules, 3) a potential mechanism to regenerate electron-accepting quinones, and, in some cases, 4) a means to alleviate the toxicity of unsaturated aromatic acids. This mechanism for CO2 generation without concomitant CH4 production has the potential to regulate the global warming potential of peatlands by elevating CO2:CH4 production ratios.

  7. Phosphorus addition mitigates N2O and CH4 emissions in N-saturated subtropical forest, SW China

    Directory of Open Access Journals (Sweden)

    L. Yu

    2017-06-01

    Full Text Available Chronically elevated nitrogen (N deposition has led to severe nutrient imbalance in forest soils. Particularly in tropical and subtropical forest ecosystems, increasing N loading has aggravated phosphorus (P limitation of biomass production, and has resulted in elevated emissions of nitrous oxide (N2O and reduced uptake of methane (CH4, both of which are important greenhouse gases. Yet, the interactions of N and P and their effects on greenhouse gas emissions remain elusive. Here, we report N2O and CH4 emissions together with soil N and P data for a period of 18 months following a single P addition (79 kg P ha−1, as NaH2PO4 powder to an N-saturated, Masson pine-dominated forest soil at TieShanPing (TSP, Chongqing, south-western (SW China. We observed a significant decline in both nitrate (NO3− concentrations in soil water (5 and 20 cm depths and in soil N2O emissions, following P application. We hypothesise that enhanced N uptake by plants in response to P addition, resulted in less available NO3− for denitrification. By contrast to most other forest ecosystems, TSP is a net source of CH4. P addition significantly decreased CH4 emissions and turned the soil from a net source into a net sink. Based on our observation and previous studies in South America and China, we believe that P addition relieves N inhibition of CH4 oxidation. Within the 1.5 years after P addition, no significant increase of forest growth was observed and P stimulation of forest N uptake by understorey vegetation remains to be confirmed. Our study indicates that P fertilisation of N-saturated, subtropical forest soils may mitigate N2O and CH4 emissions, in addition to alleviating nutrient imbalances and reducing losses of N through NO3− leaching.

  8. Prediction CH4 Emissions from the Wetlands in the Sanjiang Plain of Northeastern China in the 21st Century.

    Directory of Open Access Journals (Sweden)

    Tingting Li

    Full Text Available The Sanjiang Plain has been experienced significant wetland loss due to expanded agricultural activities, and will be potentially restored by the China National Wetland Conservation Action Plan (NWCP in future. The objective of this study is to evaluate the impact of future climate warming and wetland restoration on wetland CH4 emissions in northeast China. We used an atmosphere-vegetation interaction model (AVIM2 to drive a modified biogeophysical model (CH4MODwetland, and projected CH4 flux variations from the Sanjiang Plain wetlands under different Representative Concentration Pathway scenarios throughout the 21st century. Model validation showed that the regressions between the observed and simulated CH4 fluxes by the modified model produced an R2 of 0.49 with a slope of 0.87 (p<0.001, n = 237. According to the AVIM2 simulation, the net primary productivity of the Sanjiang Plain wetlands will increase by 38.2 g m-2 yr-1, 116.6 g m-2 yr-1 and 250.4 g m-2 yr-1 under RCP 2.6, RCP 4.5 and RCP 8.5, respectively, by the end of this century. For RCP 2.6, 4.5 and 8.5 scenarios, the CH4 fluxes will increase by 5.7 g m-2 yr-1, 57.5 g m-2 yr-1 and 112.2 g m-2 yr-1. Combined with the wetland restoration, the regional emissions will increase by 0.18‒1.52 Tg. The CH4 emissions will be stimulated by climate change and wetland restoration. Regional wetland restoration planning should be directed against different climate scenarios in order to suppress methane emissions.

  9. Environmental controls of temporal and spatial variability in CO2 and CH4 fluxes in a neotropical peatland.

    Science.gov (United States)

    Wright, Emma L; Black, Colin R; Turner, Benjamin L; Sjögersten, Sofie

    2013-12-01

    Tropical peatlands play an important role in the global storage and cycling of carbon (C) but information on carbon dioxide (CO2) and methane (CH4) fluxes from these systems is sparse, particularly in the Neotropics. We quantified short and long-term temporal and small scale spatial variation in CO2 and CH4 fluxes from three contrasting vegetation communities in a domed ombrotrophic peatland in Panama. There was significant variation in CO2 fluxes among vegetation communities in the order Campnosperma panamensis > Raphia taedigera > Cyperus. There was no consistent variation among sites and no discernible seasonal pattern of CH4 flux despite the considerable range of values recorded (e.g. -1.0 to 12.6 mg m(-2) h(-1) in 2007). CO2 fluxes varied seasonally in 2007, being greatest in drier periods (300-400 mg m(-2) h(-1)) and lowest during the wet period (60-132 mg m(-2) h(-1)) while very high emissions were found during the 2009 wet period, suggesting that peak CO2 fluxes may occur following both low and high rainfall. In contrast, only weak relationships between CH4 flux and rainfall (positive at the C. panamensis site) and solar radiation (negative at the C. panamensis and Cyperus sites) was found. CO2 fluxes showed a diurnal pattern across sites and at the Cyperus sp. site CO2 and CH4 fluxes were positively correlated. The amount of dissolved carbon and nutrients were strong predictors of small scale within-site variability in gas release but the effect was site-specific. We conclude that (i) temporal variability in CO2 was greater than variation among vegetation communities; (ii) rainfall may be a good predictor of CO2 emissions from tropical peatlands but temporal variation in CH4 does not follow seasonal rainfall patterns; and (iii) diurnal variation in CO2 fluxes across different vegetation communities can be described by a Fourier model. © 2013 John Wiley & Sons Ltd.

  10. Tidal variability of CO2 and CH4 emissions from the water column within a Rhizophora mangrove forest (New Caledonia).

    Science.gov (United States)

    Jacotot, Adrien; Marchand, Cyril; Allenbach, Michel

    2018-08-01

    We performed a preliminary study to quantify CO 2 and CH 4 emissions from the water column within a Rhizophora spp. mangrove forest. Mean CO 2 and CH 4 emissions during the studied period were 3.35±3.62mmolCm -2 h -1 and 18.30±27.72μmolCm -2 h -1 , respectively. CO 2 and CH 4 emissions were highly variable and mainly driven by tides (flow/ebb, water column thickness, neap/spring). Indeed, an inverse relationship between the magnitude of the emissions and the thickness of the water column above the mangrove soil was observed. δ 13 CO 2 values ranged from -26.88‰ to -8.6‰, suggesting a mixing between CO 2 -enriched pore waters and lagoon incoming waters. In addition, CO 2 and CH 4 emissions were significantly higher during ebb tides, mainly due to the progressive enrichment of the water column by diffusive fluxes as its residence time over the forest floor increased. Eventually, we observed higher CO 2 and CH 4 emissions during spring tides than during neap tides, combined to depleted δ 13 CO 2 values, suggesting a higher contribution of soil-produced gases to the emissions. These higher emissions may result from higher renewable of the electron acceptor and enhanced exchange surface between the soil and the water column. This study shows that CO 2 and CH 4 emissions from the water column were not negligible and must be considered in future carbon budgets in mangroves. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Cryotherapy of malignant tumors: MR imaging in comparison with pathological changes in mice; Kryotherapie maligner Tumoren: Untersuchungen mittels MRT im Tierexperiment und Vergleich mit morphologischen Veraenderungen

    Energy Technology Data Exchange (ETDEWEB)

    Romaneehsen, B.; Anders, M.; Roehrl, B.; Hast, H.J.; Schiffer, I.; Neugebauer, B.; Teichmann, E.; Schreiber, W.G.; Thelen, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Hengstler, J.G. [Mainz Univ. (Germany). Inst. fuer Toxikologie

    2001-07-01

    Aim of our study was to investigate the efficacy of 7 F cryoprobes for percutaneous use morpho- and histologically, to examine the role of apoptosis after cryotherapy, and to compare contrast-enhanced MRI with histopathological findings at different time intervals in a tumor-mouse model. Methods: Percutaneous cryotherapy was performed in 15 immunocompromised nude mice with subcutaneously implanted tumors using the non-small-cell lung cancer cell line Lu 1. In group a) 7 mice were sacrificed after definite time intervals and histological examinations were done for evaluation of necrosis and apoptosis (HE; TUNEL assay); 2 mice are in long-term follow-up. In group b) in 6 mice tumor destruction and perfusion before and after freezing were investigated with native and contrast-enhanced MR imaging (T{sub 1}- and T{sub 2}-weighted spin-echo) and compared with histopathological findings. Histological control were done in 2 untreated mice. Results: We observed fast tumor-reduction within two weeks (ca. 50%). On long-term follow-up (> 6 months) no recurrence has been noticed so far. Tumors were well vascularized prior to treatment and did not-show contrast enhancement an any time after cryotherapy. A narrow contrast-enhanced zone was seen on the tumor border subcutaneously as a sign of peripheral hyperemia and central vascular stasis after cryotherapy. On histology there was evidence of both apoptosis and necrosis. (orig.) [German] Evaluierung der Durchfuehrbarkeit und Effizienz einer perkutanen Kryotherapie mittels 7-F-Kryosonde in Nacktmaeusen. Erheben des histopathologischen Befundes der Kryolaesion nach definierten Zeitintervallen und Ueberpruefung einer moeglichen Rolle der Apoptose nach Kryotherapie. Darstellung morphologischer Veraenderungen des Tumors und des angrenzenden Gewebes im Anschluss an die Kryotherapie mittels kontrastmittelunterstuetzter MRT. Methodik: Zweiminuetige Kryotherapie subkutan implantierter Tumoren eines nicht-kleinzelligen Bronchialkarzinoms

  12. Biosphere-Atmosphere Exchange of NOx, CH4, and O3 in Central Amazon

    Science.gov (United States)

    Wiedemann, K. T.; Munger, J. W.; Wofsy, S. C.; Budney, J.; Rizzo, L. V.; Campos, K.; Rocha, H.; Freitas, H.

    2016-12-01

    Oxidation by OH is the dominant pathway for removing important trace gases such as CH4, CO, CH3Br, and HCFCs. The primary source of atmospheric OH is the photolysis of O3 in the presence of water vapor, and NOx are the main precursors of O3 and OH. Thus, in NOx-rich environments that have both high humidity and high solar radiation, OH concentrations are enhanced, and therefore, tropical forests dominate global oxidation of long-lived gases. The Amazon rain forest has a unique combination of vegetation with diverse characteristics, climate, and a dynamic land use, factors that altogether govern the emission and fate of trace-gases and control particle formation and atmospheric chemistry. Understanding the interactions among the mechanisms that govern local precursor emissions will lead to a better description of the local atmospheric chemistry, which have global impacts. As part of the GoAmazon project, an array of complementary measurements was conducted in a research site in central Amazon, southeast of Santarem (PA, Brazil), situated inside the Tapajos National Forest. The site where the measurements were taken is surrounded by intact rain forest in a 6 km radius, and a 45 m closed canopy. In the east side out of this radius (upwind), some settlements are distributed in a stripe along a road, which were cleared for agriculture and are sparsely populated. The 67 m tower was assembled in the site in 2001 for flux measurements (CO2 and H2O), and included CO in order to assess local and regional biomass burning. In mid 2014 additional instrumentation were added, measuring NOx, O3, CH4, and SO2 fluxes and profiles. The SO2 measurements (until early 2015) showed concentrations up to 0.1 ppb during the peak of the dry season, and a small vertical gradient, suggesting the predominance of biogenic sources. Preliminary results show no significant seasonality in the daytime and nighttime O3 vertical profiles. Occasionally, nighttime profiles showed high concentrations for

  13. Determination of Model Kinetics for Forced Unsteady State Operation of Catalytic CH4 Oxidation

    Directory of Open Access Journals (Sweden)

    Effendy Mohammad

    2016-01-01

    Full Text Available The catalytic oxidation of methane for abating the emission vented from coal mine or natural gas transportation has been known as most reliable method. A reverse flow reactor operation has been widely used to oxidize this methane emission due to its capability for autothermal operation and heat production. The design of the reverse flow reactor requires a proper kinetic rate expression, which should be developed based on the operating condition. The kinetic rate obtained in the steady state condition cannot be applied for designing the reactor operated under unsteady state condition. Therefore, new approach to develop the dynamic kinetic rate expression becomes indispensable, particularly for periodic operation such as reverse flow reactor. This paper presents a novel method to develop the kinetic rate expression applied for unsteady state operation. The model reaction of the catalytic methane oxidation over Pt/-Al2O3 catalyst was used with kinetic parameter determined from laboratory experiments. The reactor used was a fixed bed, once-through operation, with a composition modulation in the feed gas. The switching time was set at 3 min by varying the feed concentration, feed flow rate, and reaction temperature. The concentrations of methane in the feed and product were measured and analysed using gas chromatography. The steady state condition for obtaining the kinetic rate expression was taken as a base case and as a way to judge its appropriateness to be applied for dynamic system. A Langmuir-Hinshelwood reaction rate model was developed. The time period during one cycle was divided into some segments, depending on the ratio of CH4/O2. The experimental result shows that there were kinetic regimes occur during one cycle: kinetic regime controlled by intrinsic surface reaction and kinetic regime controlled by external diffusion. The kinetic rate obtained in the steady state operation was not appropriate when applied for unsteady state operation

  14. Inter-annual variability and trend detection of urban CO2, CH4 and CO emissions

    Science.gov (United States)

    Lauvaux, T.; Deng, A.; Gurney, K. R.; Nathan, B.; Ye, X.; Oda, T.; Karion, A.; Hardesty, M.; Harvey, R. M.; Richardson, S.; Whetstone, J. R.; Hutyra, L.; Davis, K. J.; Brewer, A.; Gaudet, B. J.; Turnbull, J. C.; Sweeney, C.; Shepson, P. B.; Miles, N.; Bonin, T.; Wu, K.; Balashov, N. V.

    2017-12-01

    The Indianapolis Flux (INFLUX) Experiment has conducted an unprecedented volume of atmospheric greenhouse gas measurements across the Indianapolis metropolitan area from aircraft, remote-sensing, and tower-based observational platforms. Assimilated in a high-resolution urban inversion system, atmospheric data provide an independent constraint to existing emission products, directly supporting the integration of economic data into urban emission systems. We present here the first multi-year assessment of carbon dioxide (CO2), methane (CH4), and carbon monoxide (CO) emissions from anthropogenic activities in comparison to multiple bottom-up emission products. Biogenic CO2 fluxes are quantified using an optimized biogeochemical model at high resolution, further refined within the atmospheric inversion system. We also present the first sector-based inversion by jointly assimilating CO2 and CO mixing ratios to quantify the dominant sectors of emissions over the entire period (2012-2015). The detected trend in CO2 emissions over 2012-2015 from both bottom-up emission products and tower-based inversions agree within a few percent, with a decline in city emissions over the 3-year time period. Major changes occur at the primary power plant, suggesting a decrease in energy production within the city limits. The joint assimilation of CO2 and CO mixing ratios confirms the absence of trends in other sectors. However, top-down and bottom-up approaches tend to disagree annually, with a decline in urban emissions suggested by atmospheric data in 2014 that is several months earlier than is observed in the bottom-up products. Concerning CH4 emissions, the inversion shows a decrease since mid-2014 which may be due to lower landfill emissions or lower energy consumption (from coal and natural gas). This first demonstration of a high-accuracy long-term greenhouse gas measurement network merged with a high-resolution bottom-up information system highlights the potential for informing

  15. Corona discharge experiments in admixtures of N2 and CH4: a laboratory simulation of Titan's atmosphere

    OpenAIRE

    Horvath, G.; Skalny, J. D.; Mason, N. J.; Klas, M.; Zahoran, M.; Vladoiu, R.; Manole, M.

    2009-01-01

    A positive corona discharge fed by a N2:CH4 mixture (98:2) at atmospheric pressure and ambient temperature has been studied as a laboratory mimic of the chemical processes occurring in the atmosphere of Titan, Saturn's largest moon. In-situ measurements of UV and IR transmission spectra within the discharge have shown that the main chemical product is C2H2, produced by dissociation of CH4, with small but significant traces of ethane and HCN, all species that have been detected in Titan's atmo...

  16. Gully hotspot contribution to landscape methane (CH4) and carbon dioxide (CO2) fluxes in a northern peatland

    International Nuclear Information System (INIS)

    McNamara, N.P.; Plant, T.; Oakley, S.; Ward, S.; Wood, C.; Ostle, N.

    2008-01-01

    Peatlands are long term carbon catchments that sink atmospheric carbon dioxide (CO 2 ) and source methane (CH 4 ). In the uplands of the United Kingdom ombrotrophic blanket peatlands commonly exist within Calluna vulgaris (L.) dominated moorland ecosystems. These landscapes contain a range of topographical features that influence local hydrology, climate and plant community composition. In this study we examined the variation in ecosystem CO 2 respiration and net CH 4 fluxes from typical plant-soil systems in dendritic drainage gullies and adjacent blanket peat during the growing season. Typically, Eriophorum spp., Sphagnum spp. and mixed grasses occupied gullies while C. vulgaris dominated in adjacent blanket peat. Gross CO 2 respiration was highest in the areas of Eriophorum spp. (650 ± 140 mg CO 2 m -2 h -1 ) compared to those with Sphagnum spp. (338 ± 49 mg CO 2 m -2 h -1 ), mixed grasses (342 ± 91 mg CO 2 m -2 h -1 ) and C. vulgaris (174 ± 63 mg CO 2 m -2 h -1 ). Measurements of the net CH 4 flux showed higher fluxes from the Eriophorum spp (2.2 ± 0.6 mg CH 4 m -2 h -1 ) locations compared to the Sphagnum spp. (0.6 ± 0.4 mg CH 4 m -2 h -1 ), mixed grasses (0.1 ±0.1 mg CH 4 m -2 h -1 ) and a negligible flux detected from C. vulgaris (0.0 ± 0.0 mg CH 4 m -2 h -1 ) locations. A GIS approach was applied to calculate the contribution of gullies to landscape scale greenhouse gas fluxes. Findings from the Moor House National Nature Reserve in the UK showed that although gullies occupied only 9.3% of the total land surface, gullies accounted for 95.8% and 21.6% of the peatland net CH 4 and CO 2 respiratory fluxes, respectively. The implication of these findings is that the relative contribution of characteristic gully systems need to be considered in estimates of landscape scale peatland greenhouse gas fluxes

  17. High net CO2 and CH4 release at a eutrophic shallow lake on a formerly drained fen

    Science.gov (United States)

    Franz, Daniela; Koebsch, Franziska; Larmanou, Eric; Augustin, Jürgen; Sachs, Torsten

    2016-05-01

    Drained peatlands often act as carbon dioxide (CO2) hotspots. Raising the groundwater table is expected to reduce their CO2 contribution to the atmosphere and revitalise their function as carbon (C) sink in the long term. Without strict water management rewetting often results in partial flooding and the formation of spatially heterogeneous, nutrient-rich shallow lakes. Uncertainties remain as to when the intended effect of rewetting is achieved, as this specific ecosystem type has hardly been investigated in terms of greenhouse gas (GHG) exchange. In most cases of rewetting, methane (CH4) emissions increase under anoxic conditions due to a higher water table and in terms of global warming potential (GWP) outperform the shift towards CO2 uptake, at least in the short term.Based on eddy covariance measurements we studied the ecosystem-atmosphere exchange of CH4 and CO2 at a shallow lake situated on a former fen grassland in northeastern Germany. The lake evolved shortly after flooding, 9 years previous to our investigation period. The ecosystem consists of two main surface types: open water (inhabited by submerged and floating vegetation) and emergent vegetation (particularly including the eulittoral zone of the lake, dominated by Typha latifolia). To determine the individual contribution of the two main surface types to the net CO2 and CH4 exchange of the whole lake ecosystem, we combined footprint analysis with CH4 modelling and net ecosystem exchange partitioning.The CH4 and CO2 dynamics were strikingly different between open water and emergent vegetation. Net CH4 emissions from the open water area were around 4-fold higher than from emergent vegetation stands, accounting for 53 and 13 g CH4 m-2 a-1 respectively. In addition, both surface types were net CO2 sources with 158 and 750 g CO2 m-2 a-1 respectively. Unusual meteorological conditions in terms of a warm and dry summer and a mild winter might have facilitated high respiration rates. In sum, even after 9

  18. Westliche und muslimische Geschlechter? Western and Muslim Genders?

    Directory of Open Access Journals (Sweden)

    Stanislawa Paulus

    2008-11-01

    Full Text Available Mihçiyazgan geht der Frage nach wie Differenzen in männlichen und weiblichen Subjektkonstutionen im Westen und im Islam empirisch erfasst werden können. Hierbei verfolgt sie eine antiessentialitische Perspektive, in der sie sich zentral auf Judith Butler und Michel Foucault bezieht. Über beide hinausgehend entwickelt sie ein Modell pluraler Diskurse, mit dessen Hilfe kulturelle bedingte Geschlechterkonstruktionen verstehbar werden. Anhand einer Untersuchung von Interviews, in der sie interaktionsanalytische und diskursanalytische Herangehensweisen verbindet, macht sie unterschiedliche Zonen des Sagbaren und Unsagbaren in westlichen und muslimischen Geschlechterdiskursen sichtbar.Mihçiyazgan approaches the question as to how differences in the constitution of the subject in men and women in the west and in Islam can be empirically measured. She takes an anti-essentialist perspective, referring primarily to Judith Butler and Michel Foucault. Going beyond both, however, she develops a model of plural discourses with which gender constructions that are contingent on culture can be understood. On the basis of interviews, in which she connects her approaches through an interactional and discursive analysis, she makes visible different zones of the speakable and the unspeakable in western and Muslim gender discourses. She points to partially discursive incongruities, referring in particular to Muslim men in marginalized positions. The model presented offers a contribution to understanding discourse analysis as an empirical method. It needs to be made more dynamic, however, in order to avoid cultural codification.

  19. Veno-occlusive liver disease after infradiaphragmatic total lymphoid irradiation. A rare complication; Die Venenverschlusskrankheit der Leber nach infradiaphragmaler total lymphatischer Bestrahlung. Eine seltene Nebenwirkung

    Energy Technology Data Exchange (ETDEWEB)

    Bischof, M.; Zierhut, D.; Gutwein, S.; Wannenmacher, M. [Heidelberg Univ. (DE.) Abt. fuer Klinische Radiologie - Schwerpunkt Strahlentherapie; Hansmann, J. [Heidelberg Univ. (DE.) Abt. fuer Radiologische Diagnostik; Stremmel, W.; Mueller, M. [Heidelberg Univ. (DE). Abt. Innere Medizin 4 (Schwerpunkt Gastroenterologie)

    2001-06-01

    -jaehrigen Patienten mit einem zentrozytisch-zentroblastischen Non-Hodgkin-Lymphom, Stadium IA (Lokalisation: Linke Leiste) wurde die gesamte Abdomen- und Beckenregion ('abdominelles Bad') bestrahlt. Bei einer woechentlichen Fraktionierung von fuenfmal 1,5 Gy wurde eine Gesamtdosis von 30 Gy appliziert. Zum Schutz der Risikoorgane wurden Nierenbloecke nach 13,5 Gy und Leberbloecke nach 25 Gy eingesetzt. Waehrend der letzten beiden Therapietage kam es zur Verschlechterung des Allgemeinzustandes des Patienten mit Gewichtszunahme, Vergroesserung des Bauchumfanges, Dyspnoe und einem Anstieg der Leberwerte. Die weiterfuehrende Diagnostik ergab eine Hepatosplenomegalie mit ausgepraegter Aszitesbildung und einen erhoehten portosystemischen Druckgradienten. Im Leberbiopsat wurde eine Venenverschlusskrankheit gefunden. Innerhalb 1 Woche nach Anlage eines transjungulaeren intrahepatischen portosystemischen Stent-Shunts (TIPSS), Vollheparinisierung und unter Diuretikagabe war der Patient beschwerdefrei. Die Leberwerte sind im Normbereich. Schlussfolgerung: Die Venenverschlusskrankheit der Leber (VOD) ist eine sehr seltene Nebenwirkung bei der abdominellen Bestrahlung nicht vorbehandelter follikulaerer Keimzentrumslymphome. Bei Oberbauchbeschwerden, Anstieg der Leberenzyme sowie Aszitesbildung, insbesondere in einem Zeitraum von bis zu 4 Monaten nach Therapieabschluss, muss an diese Komplikation gedacht werden. Genese, Diagnostik und Therapie der Venenverschlusskrankheit der Leber werden im Literaturueberblick praesentiert. (orig.)

  20. CFD calculation of a catalyst near the engine connected in series with an exhaust turbocharger; CFD-Berechnung fuer einen motornahen Katalysator nach Abgasturbolader

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, R.; Olesen, M. [Zeuna Staerker GmbH und Co. KG (Germany)

    2002-06-01

    Under the pressure of ever shorter development times and high demands on exhaust systems in terms of exhaust counterpressure, acoustic and sensory aspects and exhaust purification, Zeuna Staerker started at an early stage to use advanced CFD methods in their product development process. The contribution investigates the effects of simplified assumptions of boundary conditions, using laser optical flow measurements on a turbocharger with a catalyst near the engine. [German] Immer kuerzer werdende Entwicklungszeiten und die hohen Anforderungen an Abgasanlagen hinsichtlich Abgasgegendruck, Akustik, Sensorik und Abgasreinigung fuehrten bei Zeuna Staerker schon fruehzeitig zur Etablierung ausgereifter CFD-Methoden im Produktentwicklungsprozess. Doch wie stark werden CFD-Berechnungen durch die aufgepraegten Randbedingungen beeinflusst, wenn diese nach Abgasturbolader oft vereinfacht angenommen werden muessen? Mit Hilfe laseroptischer Stroemungsmessungen an einem Abgasturbolader mit motornahem Katalysator wird dieser Frage nachgegangen. (orig.)

  1. Studierbereitschaft und Wahl von ingenieurwissenschaftlichen Studienfächern: Eine empirische Untersuchung sächsischer Abiturienten der Abschlussjahrgänge 1996, 1998 und 2000

    OpenAIRE

    Becker, Rolf

    2000-01-01

    Ausgangspunkt der vorliegenden empirischen Untersuchung ist zum einen die Frage, warum nach einem rückläufigen Trend bis 1998 die Studierneigung sächsischer Abiturienten wieder angestiegen ist und zum anderen die Frage, warum sich seit 1996 wieder mehr sächsische Abiturienten für das Ingenieurstudium interessieren. Diese Entwicklung wird anhand der Humankapital- und Werterwartungstheorie zu erklären versucht. Im Vordergrund stehen dabei die Mechanismen, die letztlich zur Entscheidung für oder...

  2. Diffuser Haarausfall und klinische Endokrinologie: Neue Erkenntnisse

    Directory of Open Access Journals (Sweden)

    Liptak J

    2013-01-01

    Full Text Available Diffuser Haarausfall ist ein häufiges Krankheitsbild in der täglichen Praxis, dessen Diagnostik allerdings oft eine Herausforderung darstellt. In den vergangenen 10 Jahren wurden große Fortschritte in der Erforschung der Effekte diverser Hormone erzielt. In murinen Haarfollikeln wird Corticoliberin (Corticotropin-releasing Hormone [CRH] mit einem Peak in der Anagenphase (Wachstumsphase exprimiert. Ein stressinduziert erhöhter CRH-Spiegel kann durch Aktivierung von Mastzellen zu erhöhtem Haarverlust führen. Melatonin wird ebenfalls im Haarfollikel exprimiert und wirkt dort auf unterschiedliche Rezeptoren. Besonders der nukleäre Retinoic Acid Receptor-(RAR- Related Orphan-Receptor alpha (RORα scheint regulatorisch auf haarzyklusabhängige Prozesse zu wirken und wird auch abhängig vom Haarzyklus exprimiert. Melatonin greift zudem in androgen- und östrogenvermittelte Signaltransduktionswege ein. Eine topische Anwendung von Melatonin kann zu einer Zunahme der Anagenhaare führen. Auch Leptin wird im Haarfollikel exprimiert und beeinflusst Haarwachstum und Hautregeneration durch Aktivierung von STAT3. Bei Mäusen konnte durch Leptin die Anagenphase induziert werden. Über den Zusammenhang zwischen androgenetischer Alopezie und Metabolischem Syndrom wurden zahlreiche widersprüchliche Daten veröffentlicht. Zuletzt wies eine große koreanische Studie eine positive Assoziation der Krankheitsbilder bei Frauen nach, jedoch nicht bei Männern. Prolaktin induziert den verfrühten Übergang zur Katagenphase, senkt die Proliferationsrate der Keratinozyten im Haarfollikel und steigert deren Apoptoserate. Eine zu Haarausfall führende Hyperprolaktinämie kann unter anderem durch diverse Medikamente, insbesondere typische und atypische Neuroleptika, hervorgerufen werden. Zahlreiche Studien an Mäusen konnten belegen, dass der Vitamin-D-Rezeptor (VDR eng mit dem Haarwachstum assoziiert ist. Dieser scheint den Haarzyklus unabhängig von seinen Liganden

  3. Sport und soziale Integration

    OpenAIRE

    Turan, Günes

    2012-01-01

    Sport und soziale Integration : Chancen, Probleme und Perspektiven für Städte und Kommunen ; Tagungsband der gleichnamigen Tagung am 28. und 29. Juni 2011 in Augsburg / Helmut Altenberger ... (Hrsg.). - Hamburg : Feldhaus, Ed. Czwalina, 2012. - 104 S. - (Sportwissenschaft und Sportpraxis ; 161)

  4. Logos und etos der Heiligkeit im Licht der liturgischen Texte vom hl. Stanislaus, Bischof und Märtyrer

    Directory of Open Access Journals (Sweden)

    Jan Józef Janicki

    2003-12-01

    Full Text Available Im Jahr 2003 feiert die Kirche in Polen das 750-jährige Jubiläum der Heiligsprechung des Bischofs Stanislaus (1030-1079, der im Jahre 1253 in Assisi, als erste Pole, kanonisiert wurde und zum Patron von ganz Polen ernannt. Der Verfasser analisiert das Messformular und Stundengebetsformular von der liturgischen Feier des hl. Stanislaus, Bischof und Märtyrer am 8 Mai und sucht dadurch die Lehre (logos über das christliche Leben und die konkrete Lebens-Konsequenzen (etos aufzuzeigen. Die erneuerten liturgischen Texte der Gebete des neuen römischen Messbuches und des Stundengebetes zeigen den Glauben der betenden Kirche nach dem alten Prinzip: legem credendi lex statuat supplicandi (oder kurz ausgedrückt: lex orandi lex credendi. Der Zweck also des hier vorgestellten Artikels ist es, den Glauben der Kirche über das heilige Leben der Christen zu demonstrieren, welches uns eine Analyse der euchologischen Texte und der Texte der Wortliturgie ermöglicht. Der Verfasser benutzte dann die Möglichkeit, diese ganze Problematik im breiten theologisch-liturgischen und pastoralen Kontext darzustellen. Dabei benutzte er die Dokumente der Kirche der letzten Jahre, insbesondere die Lehre des II. Vatikanischen Konzils wenn es um den pastoralen Dienst der Bischöfe geht, dann die pastoral-theologischen Briefe des Papstes Pius XII und des Papstes Johannes Paul II, zum 700-jährigen und zum 750-jährigen Jubiläum der Kanonisation des hl. Bischofs Stanislaus. Es geht aber auch um alles das, was Johannes Paul II und früher als Kardinal Karol Wojtyła zum Jahrestag des Märtyrertodes geschrieben hat. Die liturgischen Gebetstexte lex orandi und die Wortliturgie unterstreichen in ihrer lex credendi, dass der hl. Stanislaus in seinem Leben, in seiner Zeit und seiner Kirche, den Auftrag und die Vollmacht - die Christus den Aposteln und ihren Nachfolgern gegeben hat - alle Völker zu lehren, die Menschen in der Wahrheit zu heiligen und sie zu weiden, verwirklicht

  5. Vacuum ultraviolet photochemistry of CH4 and isotopomers. II. Product channel fields and absorption spectra

    International Nuclear Information System (INIS)

    Wang, Jen-Han; Liu, Kopin; Min, Zhiyuan; Su, Hongmei; Bersohn, Richard; Preses, Jack; Larese, John Z.

    2000-01-01

    In part I of this work the relative velocities and anisotropies of the atomic H and D fragments from methane photolysis at 10.2 eV were measured. In this paper the relative abundance of the methyl and methylene fragments are reported. A complete set of quantum yields for the different photodissociation channels of each isotopomer is obtained by combining the two sets of data. Previously it was found that H atoms are almost four times more likely than D atoms to be ejected; now it is found that hydrogen molecule photofragments are much richer in H atoms than in D. Overall, the heavier D atoms are more likely than the H atoms to remain attached to the carbon atom. An implication for astrophysics is discussed. The VUV absorption spectra of CH 4 and CH 3 D are almost identical both at room temperature and 75 K. There is, as expected, no variation in the absorption spectrum with temperature. Evidence is given that all or almost all of the methylene is produced in the a 1 A 1 and not in the ground 3 B 1 state. (c) 2000 American Institute of Physics

  6. Homogeneity of Continuum Model of an Unsteady State Fixed Bed Reactor for Lean CH4 Oxidation

    Directory of Open Access Journals (Sweden)

    Subagjo

    2014-07-01

    Full Text Available In this study, the homogeneity of the continuum model of a fixed bed reactor operated in steady state and unsteady state systems for lean CH4 oxidation is investigated. The steady-state fixed bed reactor system was operated under once-through direction, while the unsteady-state fixed bed reactor system was operated under flow reversal. The governing equations consisting of mass and energy balances were solved using the FlexPDE software package, version 6. The model selection is indispensable for an effective calculation since the simulation of a reverse flow reactor is time-consuming. The homogeneous and heterogeneous models for steady state operation gave similar conversions and temperature profiles, with a deviation of 0.12 to 0.14%. For reverse flow operation, the deviations of the continuum models of thepseudo-homogeneous and heterogeneous models were in the range of 25-65%. It is suggested that pseudo-homogeneous models can be applied to steady state systems, whereas heterogeneous models have to be applied to unsteady state systems.

  7. Tropical/Subtropical Peatland Development and Global CH4 during the Last Glaciation.

    Science.gov (United States)

    Xu, Hai; Lan, Jianghu; Sheng, Enguo; Liu, Yong; Liu, Bin; Yu, Keke; Ye, Yuanda; Cheng, Peng; Qiang, Xiaoke; Lu, Fengyan; Wang, Xulong

    2016-07-28

    Knowledge of peatland development over the tropical/subtropical zone during the last glaciation is critical for understanding the glacial global methane cycle. Here we present a well-dated 'peat deposit-lake sediment' alternate sequence at Tengchong, southwestern China, and discuss the peatland development and its linkage to the global glacial methane cycle. Peat layers were formed during the cold Marine Isotope Stage (MIS)-2 and -4, whereas lake sediments coincided with the relatively warm MIS-3, which is possibly related to the orbital/suborbital variations in both temperature and Asian summer monsoon intensity. The Tengchong peatland formation pattern is broadly synchronous with those over subtropical southern China and other tropical/subtropical areas, but it is clearly in contrast to those over the mid-high Northern Hemisphere. The results of this work suggest that the shifts of peatland development between the tropical/subtropical zone and mid-high Northern Hemisphere may have played important roles in the glacial/interglacial global atmospheric CH4 cycles.

  8. A theoretical study of CH4 dissociation on pure and gold-alloyed Ni(111) surfaces

    DEFF Research Database (Denmark)

    Kratzer, P.; Hammer, Bjørk; Nørskov, Jens Kehlet

    1996-01-01

    We present a density functional theory study of the first step of CH4 adsorption on the Ni(111) surface, dissociation into adsorbed CH3 and H. The rupture of the C-H bond occurs preferentially on top of a Ni atom, with a dissociation barrier of about 100 kJ/mol (including zero point corrections......). The transition state involves considerable internal excitation of the molecule. The active C-H bond is both stretched to 1.6 Angstrom and tilted relative to the methyl group. A normal mode analysis shows that the reaction coordinate is mainly a C-H stretch, while the orientation of the C-H bond relative...... to the surface is responsible for the highest real mode. Alloying the surface with gold also affects the reactivity of the Ni atoms on adjacent surface sites. The dissociation barrier is increased by 16 and 38 kJ/mol for a Ni atom with one or two gold neighbors, respectively. We attribute these changes...

  9. CH4/air homogeneous autoignition: A comparison of two chemical kinetics mechanisms

    KAUST Repository

    Tingas, Efstathios Al.

    2018-03-11

    Reactions contributing to the generation of the explosive time scale that characterise autoignition of homogeneous stoichiometric CH4/air mixture are identified using two different chemical kinetics models; the well known GRI-3.0 mechanism (53/325 species/reactions with N-chemistry) and the AramcoMech mechanism from NUI Galway (113/710 species/reactions without N-chemistry; Combustion and Flame 162:315-330, 2015). Although the two mechanisms provide qualitatively similar results (regarding ignition delay and profiles of temperature, of mass fractions and of explosive time scale), the 113/710 mechanism was shown to reproduce the experimental data with higher accuracy than the 53/325 mechanism. The present analysis explores the origin of the improved accuracy provided by the more complex kinetics mechanism. It is shown that the reactions responsible for the generation of the explosive time scale differ significantly. This is reflected to differences in the length of the chemical and thermal runaways and in the set of the most influential species.

  10. Production of hydrogen through the carbonation-calcination reaction applied to CH4/CO2 mixtures

    International Nuclear Information System (INIS)

    Barelli, L.; Bidini, G.; Corradetti, A.; Desideri, U.

    2007-01-01

    The production of hydrogen combined with carbon capture represents a possible option for reducing CO 2 emissions in atmosphere and anthropogenic greenhouse effect. Nowadays the worldwide hydrogen production is based mainly on natural gas reforming, but the attention of the scientific community is focused also on other gas mixtures with significant methane content. In particular mixtures constituted mainly by methane and carbon dioxide are extensively used in energy conversion applications, as they include land-fill gas, digester gas and natural gas. The present paper addresses the development of an innovative system for hydrogen production and CO 2 capture starting from these mixtures. The plant is based on steam methane reforming, coupled with the carbonation and calcination reactions for CO 2 absorption and desorption, respectively. A thermodynamic approach is proposed to investigate the plant performance in relation to the CH 4 content in the feeding gas. The results suggest that, in order to optimize the hydrogen purity and the efficiency, two different methodologies can be adopted involving both the system layout and operating parameters. In particular such methodologies are suitable for a methane content, respectively, higher and lower than 65%

  11. CO2–CH4 permeation in high zeolite 4A loading mixed matrix membranes

    KAUST Repository

    Adams, Ryan T.

    2011-02-01

    Mixed matrix membranes (MMMs) with low particle loadings have been shown to improve the properties of pure polymers for many gas separations. Comparatively few reports have been made for high particle loading (≥50vol.%) MMMs. In this work, CO2-CH4 feeds were used to study the potential of 50vol.% zeolite 4A-poly(vinyl acetate) (PVAc) MMMs for natural gas separations. A low CO2 partial pressure mixed feed probed MMM performance below the plasticization pressure of PVAc and a high CO2 partial pressure mixed feed probed MMM performance at industrially relevant conditions above the plasticization pressure.Under both mixed feed conditions at 35°C, substantial improvements in overall separation performance were observed. At low CO2 partial pressures, CO2 permeability roughly doubled with a nearly 50% increase in selectivity versus pure PVAc under the same conditions. For the high CO2 partial pressure feed, CO2 permeability remained effectively unchanged with a 63% increase in selectivity versus pure PVAc. Surprisingly, the performance of these PVAc based MMMs approached the properties of current " upper bound" polymers. Overall, this work shows that significantly improved performance MMMs can be made with traditional techniques from a low cost, low performance polymer without costly adhesion promoters. © 2010.

  12. CO2–CH4 permeation in high zeolite 4A loading mixed matrix membranes

    KAUST Repository

    Adams, Ryan T.; Lee, Jong Suk; Bae, Tae-Hyun; Ward, Jason K.; Johnson, J.R.; Jones, Christopher W.; Nair, Sankar; Koros, William J.

    2011-01-01

    Mixed matrix membranes (MMMs) with low particle loadings have been shown to improve the properties of pure polymers for many gas separations. Comparatively few reports have been made for high particle loading (≥50vol.%) MMMs. In this work, CO2-CH4 feeds were used to study the potential of 50vol.% zeolite 4A-poly(vinyl acetate) (PVAc) MMMs for natural gas separations. A low CO2 partial pressure mixed feed probed MMM performance below the plasticization pressure of PVAc and a high CO2 partial pressure mixed feed probed MMM performance at industrially relevant conditions above the plasticization pressure.Under both mixed feed conditions at 35°C, substantial improvements in overall separation performance were observed. At low CO2 partial pressures, CO2 permeability roughly doubled with a nearly 50% increase in selectivity versus pure PVAc under the same conditions. For the high CO2 partial pressure feed, CO2 permeability remained effectively unchanged with a 63% increase in selectivity versus pure PVAc. Surprisingly, the performance of these PVAc based MMMs approached the properties of current " upper bound" polymers. Overall, this work shows that significantly improved performance MMMs can be made with traditional techniques from a low cost, low performance polymer without costly adhesion promoters. © 2010.

  13. Measurements of N2O and CH4 from the aerated composting of food waste

    International Nuclear Information System (INIS)

    He, Y.; Sun, T.; Inamori, Y.; Mizuochi, M.; Kong, H.; Iwami, N.

    2000-01-01

    Emissions of N 2 O and CH 4 from an aerated composting system were investigated using small-scale simulated reactors. The results show relatively high emissions of N 2 O at the beginning of composting, in proportion to the application amount of food waste. After 2 days, the N 2 O emission decreased to 0.53 ppmv on average, near to the background level in the atmosphere (0.45 ppmv). The addition of composted cattle manure increased N 2 O emissions not only at the beginning of composting, but also during the later period and resulted in two peak emission curves. Good correlation was observed between the N 2 O concentration at the air outlet and NO 2 - concentration in waste, suggesting a generation pathway for N 2 O from NO 2 - to N 2 O. Methane was only detected in treatments containing composted cattle manure. The high emission of methane illustrates the involvement of anoxic/anaerobic microorganisms with the addition of composted manure. The result suggests the existence of anoxic or anaerobic microsite inside the waste particles even though ventilation was employed during the composting process

  14. Intermolecular potential energy surface and thermophysical properties of the CH4-N2 system.

    Science.gov (United States)

    Hellmann, Robert; Bich, Eckard; Vogel, Eckhard; Vesovic, Velisa

    2014-12-14

    A five-dimensional potential energy surface (PES) for the interaction of a rigid methane molecule with a rigid nitrogen molecule was determined from quantum-chemical ab initio calculations. The counterpoise-corrected supermolecular approach at the CCSD(T) level of theory was utilized to compute a total of 743 points on the PES. The interaction energies were calculated using basis sets of up to quadruple-zeta quality with bond functions and were extrapolated to the complete basis set limit. An analytical site-site potential function with nine sites for methane and five sites for nitrogen was fitted to the interaction energies. The PES was validated by calculating the cross second virial coefficient as well as the shear viscosity and binary diffusion coefficient in the dilute-gas limit for CH4-N2 mixtures. An improved PES was obtained by adjusting a single parameter of the analytical potential function in such a way that quantitative agreement with the most accurate experimental values of the cross second virial coefficient was achieved. The transport property values obtained with the adjusted PES are in good agreement with the best experimental data.

  15. Literatūros mokslas ir teologija: dialogiško santykio realijos ir krikščioniškos mistinės tradicijos laukas. Literaturwissenschaft und Theologie: Realien des dialogischen Verhältnisses und das Feld der mystischen Erfahrung

    Directory of Open Access Journals (Sweden)

    Dalia Jakaitė

    2011-01-01

    Full Text Available Das wichtigste Ziel des vorliegenden Artikels ist eine Bedeutung der Mystik für die Autoren des Dialogs zwischen der Literatur(wissenschaft und Theologie zu zeigen. Dabei wird die Tradition der frühchristlichen Kirche aktualisiert. Die christliche Tradition der Mystik kommt schon in der Bibel zum Vorschein, so z. B. in der Paulusrede auf dem Areopag, die mit der Literaturtheologie in Beziehung gesetzt wird. Als Untersuchungsgegenstand dienen theoretische Studien und einige Arbeiten der Literaturkritik. Die Erfahrung erscheint als ein wesentliches Problem im Bereich der Literatur und Theologie.Kuschel, als Verbindungskette zweier bedeutungsvoller Forschungsetappen des Dialogs zwischen Literatur und Theologie in Deutschland, formuliert einen sich dynamisch verändernden Netz der strukturellen Analogien, der Theopoetik und anderer Begriffe. Als eine der wichtigsten Säulen dient in seinen Arbeiten die Steiners Konzeption der Kunstmetaphysik, die auch für andere nach einem interdisziplinären Dialog suchenden Autoren aktuell ist. Braungart betont die ästhetische Richtung der Theologie, die Literaturwissenschaft wird laut Braungart in Zusammenhang mit ästhetisch und exegetisch-hermeneutisch orientierter Theologie gesetzt. Das ästhetische Kriterium für die Bewertung der Literatur wird in Arbeiten von Sölle durch ein starkes theologisches Interesse ergänzt. Diese Autorin sucht nach Unterstützung des dialogischen Denkens und bedient sich der figurischen Methode in Auffassung von Auerbach. Im Rahmen dieser Problematik wird kontraverse Betrachtung des Begriffs der Literaturtheologie deutlich, zum Verständnis dessen Mieths Ansicht von großer Bedeutung ist. Seiner Meinung nach sei die Literaturtheologie ohne Autonomie der Poesie nicht zu gerechtfertigen, Theologie sei genausoviel ideologisch gefährlich wie gefährlich eine für die Literaturwissenschaft typische leere Ideologie sei.Die Mystik der Kircheenväter und des Mittelaters weist

  16. Diagnose und Therapie einer Depression im höheren Lebensalter – Einflüsse von Patienten- und Arztmerkmalen

    Science.gov (United States)

    von dem Knesebeck, Olaf; Bönte, Markus; Siegrist, Johannes; Marceau, Lisa; Link, Carol; McKinlay, John

    2013-01-01

    Zusammenfassung Studienergebnissee aus dem englischsprachigen Raum zeigen, dass diagnostische und therapeutische Entscheidungen von Hausärzten bei der Versorgung von depressiven Patienten systematischen Einflüssen unterliegen, und dass sowohl Merkmale des Arztes als auch des Patienten unabhängig vom Krankheitsbild Einfluss auf diese Entscheidungen haben. In der vorliegenden Arbeit werden Ergebnisse einer deutschen Studie präsentiert, in der die Einflüsse von Patienten- und Arztmerkmalen auf diagnostische und therapeutische ärztliche Entscheidungen bei einer Depression untersucht wurden. Unter Anwendung eines faktoriellen Experimentaldesigns spielten professionelle Schauspieler in Videofilmen die Rolle von Patienten, die Symptome für eine depressive Erkrankung äußern. In den Videofilmen, die alle auf einem identischen Skript basieren, wurden systematisch die Patientenmerkmale Alter (55 vs. 75 Jahre), Geschlecht und sozialer Status (Hausmeister vs. Lehrer) variiert. Die randomisierte Ärztestichprobe wurde nach dem Arztgeschlecht und professioneller Erfahrung ( 15 Jahre) geschichtet. Der Videofilm wurde insgesamt 128 niedergelassenen Ärzten für Allgemeinmedizin und hausärztlich tätigen Internisten in ihrer Praxis vorgespielt. Danach wurden die Ärzte zu unterschiedlichen Aspekten von Diagnose und Therapie befragt. Es wurde erhoben, ob der Arzt dem Patienten über das gezeigte Gespräch hinausgehende Fragen stellen würde, welche Diagnosen er für wahrscheinlich hält, wie sicher er sich mit seiner Diagnose ist, welche diagnostischen Tests er anordnen würde, ob er den Patienten überweisen würde oder ob er Medikamente verordnen oder ihm Empfehlungen zur Änderung seines Lebensstils geben würde. Die Ergebnisse weisen darauf hin, dass sowohl die Diagnose als auch die Therapie einer Depression durch niedergelassene Hausärzte in Deutschland nur geringfügig durch die untersuchten Merkmale der Patienten und der behandelnden Ärzte beeinflusst wird. PMID

  17. Reactivity of chemisorbed oxygen atoms and their catalytic consequences during CH4-O2 catalysis on supported Pt clusters.

    Science.gov (United States)

    Chin, Ya-Huei Cathy; Buda, Corneliu; Neurock, Matthew; Iglesia, Enrique

    2011-10-12

    Kinetic and isotopic data and density functional theory treatments provide evidence for the elementary steps and the active site requirements involved in the four distinct kinetic regimes observed during CH(4) oxidation reactions using O(2), H(2)O, or CO(2) as oxidants on Pt clusters. These four regimes exhibit distinct rate equations because of the involvement of different kinetically relevant steps, predominant adsorbed species, and rate and equilibrium constants for different elementary steps. Transitions among regimes occur as chemisorbed oxygen (O*) coverages change on Pt clusters. O* coverages are given, in turn, by a virtual O(2) pressure, which represents the pressure that would give the prevalent steady-state O* coverages if their adsorption-desorption equilibrium was maintained. The virtual O(2) pressure acts as a surrogate for oxygen chemical potentials at catalytic surfaces and reflects the kinetic coupling between C-H and O═O activation steps. O* coverages and virtual pressures depend on O(2) pressure when O(2) activation is equilibrated and on O(2)/CH(4) ratios when this step becomes irreversible as a result of fast scavenging of O* by CH(4)-derived intermediates. In three of these kinetic regimes, C-H bond activation is the sole kinetically relevant step, but occurs on different active sites, which evolve from oxygen-oxygen (O*-O*), to oxygen-oxygen vacancy (O*-*), and to vacancy-vacancy (*-*) site pairs as O* coverages decrease. On O*-saturated cluster surfaces, O*-O* site pairs activate C-H bonds in CH(4) via homolytic hydrogen abstraction steps that form CH(3) groups with significant radical character and weak interactions with the surface at the transition state. In this regime, rates depend linearly on CH(4) pressure but are independent of O(2) pressure. The observed normal CH(4)/CD(4) kinetic isotope effects are consistent with the kinetic-relevance of C-H bond activation; identical (16)O(2)-(18)O(2) isotopic exchange rates in the presence or

  18. Measurements and Interpretation of Surface Mixing Ratios of CH4 and CO and δ 13C and δ D of CH4 in Air from Pacific Ocean Transects Between Auckland, New Zealand and Los Angeles, California

    Science.gov (United States)

    Ajie, H. O.; Tyler, S. C.; Gotoh, A. A.; McMillan, A. M.; Rice, A. L.; Lowe, D. C.

    2003-12-01

    We report on measurements of atmospheric CH4 and CO mixing ratios and δ 13C of CH4 from air samples collected every 2.5 to 5° latitude along a transect over the Pacific Ocean using container ships of P&O Nedlloyd (formerly Blue Star) shipping line. Data presented here begins in June 1996 and extends to January 2002. Scientists from the National Institute of Water and Atmospheric Research in New Zealand and from University of California, Irvine alternate sampling trips so that a transect between Auckland, New Zealand (35° S) and Los Angeles, California (35° N) can be sampled over a period of ˜15 days approximately every four months. Data sets from the two laboratories are intercalibrated through a sample exchange program. The data provide detail on the spatial and seasonal variation of CH4 and CO mixing ratios and stable isotope ratios of CH4 over the Pacific equatorial region, including the Intertropical Convergence Zone (ITCZ) and both northern and southern temperate zones to about 30° latitude, including the South Pacific Convergence Zone (SPCZ). Data from 18 transect samplings so far clearly show that δ 13C in the mid latitudes of both hemispheres are ˜6 months out of phase. In June, a minimum in δ 13C CH4 in the southern hemisphere (SH) coincides approximately with the maximum in the northern hemisphere (NH) seasonal cycle. Because the NH is less enriched in 13C than the SH this situation results in a remarkably flat gradient between 30° N and 30° S. In November the opposite situation occurs with the SH mid latitude maximum coinciding with the minimum in the NH cycle, leading to a relatively large gradient of ˜0.5‰ between the hemispheres. We discuss how CH4 and CO mixing ratios are related to the changing positions and strengths of the ITCZ and SPCZ and how this data can be used in multi-dimensional models of atmospheric chemistry and transport to better define CH4 sources and sinks both temporally and spatially.

  19. Undistorted, crack-free and low-cost ceramic components for the transportation, power and medical sector - numerical simulation of pressing and sintering. Final report; Formgenaue, rissfreie und kostenguenstige Bauteile aus Keramik fuer die Verkehrs-, Energie- und Medizintechnik - Numerische Simulation des Pressens und Sinterns. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Stingl, P.; Wittig, F.

    1999-02-01

    One of the economically most important production routes for ceramic parts is die pressing and sintering. Up to now the development cycle is mainly based on empirical experience and sample production. Success or failure can be often determined only after sintering. This procedure is time and cost-intensive and sometimes could lead to the conclusion that a part is not producible at all considering economical restrictions. Finite element simulations in combination with appropriate material laws for pressing and sintering allow qualitative and quantitative predictions of undesirable distortions. Agreement with experimental data of real parts is very good. Using these simulations, the development time of a new part can be significantly reduced by optimizing die geometries, punch movements or temperature-time-curves during sintering. Thus, an effective method to improve the quality is available. (orig.) [German] Das Konstruieren und Einrichten von Werkzeugen wurde bisher hauptsaechlich ueber Musterproduktionen sowie ueber empirische Erfahrungswerte abgestimmt. Erfolg oder Misserfolg konnte oft erst nach dem Sintern beurteilt werden. Dieses Vorgehen ist zeit- und kostenintensiv und fuehrt manchmal nach langen und zeitintensiven Versuchsreihen zu dem Ergebnis, dass ein Bauteil ueber Trockenpresstechnik nicht oder nur mit unzureichender Prozesssicherheit hergestellt werden kann. Mit der numerischen Simulation des Pressens und Sinterns ist es moeglich, die Gruendichteunterschiede und damit auch den Sinterverzug beim Pressen rein rechnerisch zu ermitteln. Die Uebereinstimmung der Simulationsergebnisse mit dem realen Bauteil ist sehr gut. Damit koennen die Realisierbarkeit komplizierter Bauteile bereits am Rechner ueberprueft und Korrekturmassnahmen vorgeschlagen werden. Eine effektive Methode zur Qualitaetsverbesserung ist damit gegeben. (orig.)

  20. Carola Bauschke-Urban, Marion Kamphans, Felizitas Sagebiel (Hg.: Subversion und Intervention. Wissenschaft und Geschlechter(unordnung. Opladen u.a.: Verlag Barbara Budrich 2010.

    Directory of Open Access Journals (Sweden)

    Tina Jung

    2011-12-01

    Full Text Available Inwieweit sind die tradierten Geschlechterverhältnisse in Wissenschaft und Hochschule in Unordnung geraten? Neben empirischen Befunden, theoretischen Reflexionen und Praxisansätzen ist der vorliegende Sammelband mit biographischem Material und Würdigungen der Wissenschaftlerin Sigrid Metz-Göckel angereichert. Der Band gibt Einblicke in die Frauen- und Geschlechterforschung als nach wie vor umkämpftes Terrain in der Wissenschaftslandschaft sowie in die Universität als Arbeitsplatz, der (Karriere-Fallen und Hürden bereithält. Wissenschaft wird aber auch als Ort intellektueller und politischer Leidenschaft und (potentieller Teil eines guten Lebens begriffen. Hier schließt die Frage nach Leitorientierungen über bloß formale Geschlechtergerechtigkeit hinaus an, wie sie exemplarisch in einem Beitrag formuliert wird: Brot und Rosen!To what extent have the traditional gender relations in science and university become out of order? Besides empirical findings, theoretical reflections, and practical approaches, this anthology is enriched with biographical material and evaluations by the scientist Sigrid Metz-Göckel. The volume offers insights into women’s and gender studies as a still contested territory within the scientific community and within the university as a workplace, which holds both (career pitfalls and obstacles. However, science is also seen as a place for intellectual and political passion and a (potential part of a good life. Here, the question for a guiding orientation beyond mere formal gender equality connects as it is exemplarily formulated in one of the articles: bread and roses!

  1. Regional Variation of CH4 and N2 Production Processes in the Deep Aquifers of an Accretionary Prism.

    Science.gov (United States)

    Matsushita, Makoto; Ishikawa, Shugo; Nagai, Kazushige; Hirata, Yuichiro; Ozawa, Kunio; Mitsunobu, Satoshi; Kimura, Hiroyuki

    2016-09-29

    Accretionary prisms are mainly composed of ancient marine sediment scraped from the subducting oceanic plate at a convergent plate boundary. Large amounts of anaerobic groundwater and natural gas, mainly methane (CH4) and nitrogen gas (N2), are present in the deep aquifers associated with an accretionary prism; however, the origins of these gases are poorly understood. We herein revealed regional variations in CH4 and N2 production processes in deep aquifers in the accretionary prism in Southwest Japan, known as the Shimanto Belt. Stable carbon isotopic and microbiological analyses suggested that CH4 is produced through the non-biological thermal decomposition of organic matter in the deep aquifers in the coastal area near the convergent plate boundary, whereas a syntrophic consortium of hydrogen (H2)-producing fermentative bacteria and H2-utilizing methanogens contributes to the significant production of CH4 observed in deep aquifers in midland and mountainous areas associated with the accretionary prism. Our results also demonstrated that N2 production through the anaerobic oxidation of organic matter by denitrifying bacteria is particularly prevalent in deep aquifers in mountainous areas in which groundwater is affected by rainfall.

  2. Continuous flow IRMS application to CH4, MNHCS, and N2O in the atmosphere and the oceans

    International Nuclear Information System (INIS)

    Yoshida, N.; Tsunogai, U.; Toyoda, S.

    2001-01-01

    The application of CF-IRMS to measurement of methane (CH4), non-methane hydrocarbons (NMHCS), and nitrous oxide (N 2 O) is outlined and preliminary information on isotopic variations in the atmosphere and oceans is presented. Labelling of these compounds is expected to provide a robust method for tracing sources, sinks and controlling processes in the environment. (author)

  3. Assessing CH4 and CO2 emissions from wetlands in the Drenthe province, The Netherlands: a modelling approach

    NARCIS (Netherlands)

    Petrescu, A.J.; Huissteden, van J.; Vries, de F.; Bregman, E.P.H.; Scheper, A.

    2009-01-01

    Assessment of land use related greenhouse gas (GHG) emissions on larger spatial scales is usually achieved by modelling. Surface flux measurements are expensive and measurement locations too widely scattered to serve as spatially reliable flux estimates. Here we assess CO2 and CH4 fluxes from

  4. Biogenic CH4 and N2O emissions overwhelm land CO2 sink in Asia: Toward a full GHG budget

    Science.gov (United States)

    Tian, H.

    2017-12-01

    The recent global assessment indicates the terrestrial biosphere as a net source of greenhouse gases to the atmosphere (Tian et al Nature 2016). The fluxes of greenhouse gases (GHG) vary by region. Both TD and BU approaches indicate that human-caused biogenic fluxes of CO2, CH4 and N2O in the biosphere of Southern Asia led to a large net climate warming effect, because the 100-year cumulative effects of CH4 and N2O emissions together exceed that of the terrestrial CO2 sink. Southern Asia has about 90% of the global rice fields and represents more than 60% of the world's nitrogen fertilizer consumption, with 64%-81% of CH4 emissions and 36%-52% of N2O emissions derived from the agriculture and waste sectors. Given the large footprint of agriculture in Southern Asia, improved fertilizer use efficiency, rice management and animal diets could substantially reduce global agricultural N2O and CH4 emissions. This study highlights the importance of including all three major GHGs in regional climate impact assessments, mitigation option and climate policy development.

  5. Laboratory-scale measurements of N2O and CH4 emissions from hybrid poplars (Populus deltoides x Populus nigra).

    Science.gov (United States)

    McBain, M C; Warland, J S; McBride, R A; Wagner-Riddle, C

    2004-12-01

    The purpose of this study was to determine whether or not young hybrid poplar (Populus deltoides x Populus nigra) could transport landfill biogas internally from the root zone to the atmosphere, thereby acting as conduits for landfill gas release. Fluxes of methane (CH4) and nitrous oxide (N2O) from the seedlings to the atmosphere were measured under controlled conditions using dynamic flux chambers and a tunable diode laser trace gas analyser (TDLTGA). Nitrous oxide was emitted from the seedlings, but only when extremely high soil N2O concentrations were applied to the root zone. In contrast, no detectable emissions of CH4 were measured in a similar experimental trial. Visible plant morphological responses, characteristic of flood-tolerant trees attempting to cope with the negative effects of soil hypoxia, were observed during the CH4 experiments. Leaf chlorosis, leaf abscission and adventitious roots were all visible plant responses. In addition, seedling survival was observed to be highest in the biogas 'hot spot' areas of a local municipal solid waste landfill involved in this study. Based on the available literature, these observations suggest that CH4 can be transported internally by Populus deltoides x Populus nigra seedlings in trace amounts, although future research is required to fully test this hypothesis.

  6. An experimental and kinetic modeling study of premixed NH3/CH4/O-2/Ar flames at low pressure

    DEFF Research Database (Denmark)

    Tian, Z.Y.; Li, Y. Y.; Zhang, L. D.

    2009-01-01

    An experimental and modeling study of 11 premixed NH3/CH4/O-2/Ar flames at low pressure (4.0 kPa) with the same equivalence ratio of 1.0 is reported. Combustion intermediates and products are identified using tunable synchrotron vacuum Ultraviolet (VUV) photoionization and molecular-beam mass...

  7. Optical sensor system for time-resolved quantification of methane densities in CH4-fueled spark ignition engines.

    Science.gov (United States)

    Golibrzuch, Kai; Digulla, Finn-Erik; Bauke, Stephan; Wackerbarth, Hainer; Thiele, Olaf; Berg, Thomas

    2017-08-01

    We present the development and the first application of an optical sensor system that allows single-cycle determination of methane (CH 4 ) concentration inside internal combustion (IC) engines. We use non-dispersive infrared absorption spectroscopy to detect the CH 4 density with a time resolution up to 33 μs at acquisition rates of 30 kHz. The measurement scheme takes advantage of the strong temperature dependence of the absorption band applying two detection channels for CH 4 that detect different spectral regions of the ν 3 anti-symmetric C-H-stretch absorption. The strategy allows the simultaneous determination of fuel concentration as well as gas temperature. We show the proof-of-concept by validation of the measurement strategy in static pressure cell experiments as well as its application to a methane-fueled IC engine using a modified spark plug probe. Our results clearly demonstrate that it is crucial to determine the CH 4 temperature in the probe volume. Due to thermal influences of the sensor probe, the temperature needed to calculate the desired quantities (fuel density, fuel concentration) significantly differs from the gas phase temperature in the rest of the combustion chamber and estimations from standard thermodynamic models, e.g., polytropic compression, will fail.

  8. Effect of pressure on the lean limit flames of H2-CH4-air mixture in tubes

    NARCIS (Netherlands)

    Zhou, Z.; Shoshyn, Y.; Hernandez Perez, F.E.; van Oijen, J.A.; de Goey, L.P.H.

    2017-01-01

    The lean limit flames of H2-CH4-air mixtures stabilized inside tubes in a downward flow are experimentally and numerically investigated at elevated pressures ranging from 2 to 5 bar. For the shapes of lean limit flames, a change from ball-like flame to cap-like flame is experimentally observed with

  9. CH4/H2/Ar electron cyclotron resonance plasma etching for GaAs-based field effect transistors

    NARCIS (Netherlands)

    Hassel, van J.G.; Es, van C.M.; Nouwens, P.A.M.; Maahury, J.H.; Kaufmann, L.M.F.

    1995-01-01

    Electron cyclotron resonance (ECR) plasma etch processes with CH4/H2/AR have been investigated on different III–Vsemiconductor materials (GaAs, AlGaAs, InGaAs, and InP). The passivation depth as a function of the GaAs carrierconcentration and the recovery upon annealing at different temperatures

  10. Study of the properties of plasma of CH4/H2 and its interactions with liquid hydrocarbons

    International Nuclear Information System (INIS)

    Gambus, G.; Patino, P.

    2003-01-01

    Properties of a CH 4 /H 2 plasma, as a reducing agent in heterogeneous reactions with one olefin hydrocarbon, were studied in this work. The characterization of the plasma was carried out by means of optical emission spectroscopy, by varying the gas composition (CH 4 /H 2 ) and the working pressure, in a radio frequency discharge. The variation of the relative populations of H and CH radicals was followed, at pressures between 0.001 and 0.4 mbar and CH 4 /H 2 proportions 1:1 to 1:5. The conditions selected for treating squalene were 0.1 mbar and CH 4 /H 2 of 1:5. Although these conditions did not yield the maximum intensities for the two signals, these were strong enough and black carbon and polymers ceased from being produced under this regime. At 5 C, more than two double bonds per molecule, out of six, were hydrogenated with the plasma in 12 hours. (Author)

  11. Rate Coefficient for the (4)Heμ + CH4 Reaction at 500 K: Comparison between Theory and Experiment.

    Science.gov (United States)

    Arseneau, Donald J; Fleming, Donald G; Li, Yongle; Li, Jun; Suleimanov, Yury V; Guo, Hua

    2016-03-03

    The rate constant for the H atom abstraction reaction from methane by the muonic helium atom, Heμ + CH4 → HeμH + CH3, is reported at 500 K and compared with theory, providing an important test of both the potential energy surface (PES) and reaction rate theory for the prototypical polyatomic CH5 reaction system. The theory used to characterize this reaction includes both variational transition-state (CVT/μOMT) theory (VTST) and ring polymer molecular dynamics (RPMD) calculations on a recently developed PES, which are compared as well with earlier calculations on different PESs for the H, D, and Mu + CH4 reactions, the latter, in particular, providing for a variation in atomic mass by a factor of 36. Though rigorous quantum calculations have been carried out for the H + CH4 reac