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Sample records for temperatur unter statischer

  1. Crack initiation and crack growth in high temperature materials under cyclic thermal stresses; Rissinitiierung und Risswachstum in Hochtemperaturwerkstoffen unter zyklisch thermischer Beanspruchung

    Energy Technology Data Exchange (ETDEWEB)

    Gruen, C.

    1996-12-01

    The high temperatures of use in drive units, such as the combustion chamber or the hot gas turbine, for example, usually cause high temperature changes. Great temperature differences occur for short periods in the components, and thermal shock is produced. In this work, theoretical and experimental investigations are introduced on crack initiation and crack growth in high temperature materials under cyclic thermal stresses. The experiments were carried out with the inter-metallic phase Ni{sub 3}Al, the nickel-based alloy Nimonic 80A and the iron-based alloy PM 2000 strengthened by oxide dispersion (ODS). A characteristic crack appearance picture was found for each material, which was examined more closely. The stresses occurring in the sample during one cycle were calculated with the aid of the finite element program ABAQUS, knowing the specific material parameters. Based on the linear-elastic fracture mechanics, stress intensity factors were calculated on the superimposition principle. Using the material data from isothermal crack propagation experiments, the prediction of fatigue crack spread with cyclic thermal stresses is compared with the experimental findings. (orig./AKF) [Deutsch] Die hohen Einsatztemperaturen in Antriebsaggregaten wie z.B. der Brennkammer oder der Heissgasturbine bedingen in der Regel hohe Temperaturwechsel. Dabei treten kurzzeitig grosse Temperaturunterschiede in den Bauteilen auf, ein Thermoschock wird erzeugt. In der vorliegenden Arbeit werden theoretische und experimentelle Untersuchungen zur Rissinitiierung und zum Risswachstum in Hochtemperaturwerkstoffen unter zyklisch thermischer Belastung vorgestellt. Die Experimente wurden mit der intermetallischen Phase Ni{sub 3}Al, der Nickelbasislegierung Nimonic 80A und der oxid-dispersionsverfestigten (ODS) Eisenbasislegierung PM2000 durchgefuehrt. Fuer jeden Werkstoff stellte sich ein charakteristisches Risserscheinungsbild dar, das naeher untersucht wurde. Die in der Probe auftretenden

  2. Magnetic resonance imaging. Recent studies on biological effects of static magnetic and high-frequency electromagnetic fields; Magnetresonanztomographie. Neuere Studien zur biologischen Wirkung statischer Magnetfelder und hochfrequenter elektromagnetischer Felder

    Energy Technology Data Exchange (ETDEWEB)

    Pophof, B. [Bundesamt fuer Strahlenschutz, Abteilung fuer Wirkungen und Risiken ionisierender und nichtionisierender Strahlung, Oberschleissheim/Neuherberg (Germany); Brix, G. [Bundesamt fuer Strahlenschutz, Abteilung fuer medizinischen und beruflichen Strahlenschutz, Oberschleissheim/Neuherberg (Germany)

    2017-07-15

    During the last few years, new studies on biological effects of strong static magnetic fields and on thermal effects of high-frequency electromagnetic fields used in magnetic resonance imaging (MRI) were published. Many of these studies have not yet been included in the current safety recommendations. Scientific publications since 2010 on biological effects of static and electromagnetic fields in MRI were researched and evaluated. New studies confirm older publications that have already described effects of static magnetic fields on sensory organs and the central nervous system, accompanied by sensory perceptions. A new result is the direct effect of Lorentz forces on ionic currents in the semicircular canals of the vestibular system. Recent studies of thermal effects of high-frequency electromagnetic fields were focused on the development of anatomically realistic body models and a more precise simulation of exposure scenarios. Strong static magnetic fields can cause unpleasant sensations, in particular, vertigo. In addition, they can influence the performance of the medical staff and thus potentially endanger the patient's safety. As a precaution, medical personnel should move slowly within the field gradient. High-frequency electromagnetic fields lead to an increase in the temperature of patients' tissues and organs. This should be considered especially in patients with restricted thermoregulation and in pregnant women and neonates; in these cases exposure should be kept as low as possible. (orig.) [German] In den letzten Jahren wurden neue Studien zu biologischen Wirkungen starker statischer Magnetfelder und zu thermischen Effekten hochfrequenter elektromagnetischer Feldern, wie sie bei der Magnetresonanztomographie (MRT) verwendet werden, publiziert. Viele dieser Studien sind noch nicht in aktuelle Sicherheitsempfehlungen eingeflossen. Wissenschaftliche Publikationen ab dem Jahr 2010 zur biologischen Wirkung statischer und elektromagnetischer Felder

  3. Simulation of a model predictive room temperature control by use of an ideal weather forecast; Simulation einer praediktiven Raumtemperaturregelung unter Verwendung einer idealen Wettervorhersage

    Energy Technology Data Exchange (ETDEWEB)

    Goertler, Gregor [Fachhochschulstudiengaenge Burgenland GesmbH, Pinkafeld (Austria). Kernkompetenzbereich Energie- und Umweltmanagement; Beigelboeck, Barbara

    2010-12-15

    Due to the use of MPC (Model Predictive Control) for room heating applications users and constructors expect nameable energy savings. By usage of a simulation for a special case the energy saving potential of predictive control algorithm for room temperature control in connection with an ideal weather forecast, in comparison to established algorithms (PI-control, two level controller) is estimated. The controlled system with the control variable room temperature is a room with floor heating which was modelled in TRNSYS. A linear state space model of the controlled system was derived with suitable identification methods. This model was used by the predictive control algorithm, which was programmed in MATLAB. The weather data was taken from the TRNSYS library and has been made available also for the control algorithm, so that an ideal weather forecast was established. For the example considered in this paper, the amount of energy saving was 10 % per year with the MPC-controller compared to a PI-controller. (Copyright copyright 2010 Ernst and Sohn Verlag fuer Architektur und technische Wissenschaften GmbH and Co. KG, Berlin)

  4. Betoninstandsetzung unter Wasser : Mörtelentwicklung und Applikationstechniken

    OpenAIRE

    Nguyen-Sauerbaum, Lina Phan Anh

    2017-01-01

    Für die Instandsetzung von Betonbauteilen unter Wasser stehen aktuell keine gängigen Verfahren zur Verfügung, die ohne Trockenlegung oder Einschalen des Bauteils auskommen. Diese Arbeit legt die Grundlagen für eine Betoninstandsetzung unter Wasser ohne Einschalen des Bauwerks. Es wurden neue Mörtel entwickelt, die unter Wasser einsetzbar sind und Applikationstechniken untersucht, die eine Applikation unter Wasser mit erfolgreichem Haftverbund erlauben. There are currently no established...

  5. Geometrie verstehen: statisch - kinematisch

    Science.gov (United States)

    Kroll, Ekkehard

    Dem Allgemeinen steht begrifflich das Besondere gegenüber. In diesem Sinne sind allgemeine Überlegungen zum Verstehen von Mathematik zu ergänzen durch Untersuchungen hinsichtlich des Verstehens der einzelnen mathematischen Disziplinen, insbesondere der Geometrie. Hier haben viele Schülerinnen und Schüler Probleme. Diese rühren hauptsächlich daher, dass eine fertige geometrische Konstruktion in ihrer statischen Präsentation auf Papier nicht mehr die einzelnen Konstruktionsschritte erkennen lässt; zum Nachvollzug müssen sie daher ergänzend in einer Konstruktionsbeschreibung festgehalten werden.

  6. Calorific value and EnEV (German Energy Saving Ordinance). Why return flow temperatures are to be planned below the dew point; Brennwert und EnEV. Warum Ruecklauftemperaturen weit unter Taupunkt planen?

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2003-07-01

    Why does the efficiency of a condensing boiler system increase by 5 percent if the temperature is lowered from 45 to 30 degrees centigrade? The condensation temperature of 57-58 degrees centigrade is far higher, so the cold return flow should always remove the complete evaporation heat from the flue gas plumes and transfer it to the incoming flow. Why is this not the case?. [German] Wieso klettert der Wirkungsgrad einer Brennwertkesselanlage bei Absenkung der Kesselruecklauftemperatur von vorher 45 C auf zum Beispiel 30 C um beachtliche 5 Prozent an? Der Wasserdampftaupunkt des Abgases liegt mit 57 C oder 58 C doch in jedem Fall weit oberhalb der 45 C. Der kalte Ruecklauf muesste mithin in beiden Faellen den 58-graedigen Rauchgasschwaden die komplette Verdampfungswaerme entziehen und dem Vorlauf zufuehren - tut er aber nicht. Warum nicht? (orig.)

  7. Static-dynamic MR urography. Comparison with excretory urography and scintigraphy in experimentally induced urinary tract obstruction (UTO); Statisch-dynamische MR-Urographie. Vergleich mit Ausscheidungsurographie und Szintigraphie bei experimentell induzierter Harntransportstoerung (HTS)

    Energy Technology Data Exchange (ETDEWEB)

    Rohrschneider, W.K.; Wunsch, R.; Troeger, J. [Paediatrische Radiologie, Univ. Heidelberg (Germany); Hoffend, J. [Nuklearmedizinische Klinik, Univ. Heidelberg (Germany); Becker, K. [Inst. fuer Versuchstierkunde, Univ. Heidelberg (Germany); Darge, K.; Clorius, J.H. [Kooperationseinheit Nuklearmedizin, Deutsches Krebsforschungszentrum, Heidelberg (Germany); Kooijman, H. [Philips Medizin-Systeme, Hamburg (Germany)

    2001-02-01

    Purpose: To assess the diagnostic value of combined static-dynamic MR urography (MRU) for the functional-morphological evaluation of experimentally induced urinary tract obstruction. Methods: Static-dynamic MRU - combination study with a respiratory-triggered 3D-IR-TSE sequence and a dynamic 2D-FFE sequence after Gd-DTPA and furosemide - was obtained in comparison with {sup 99m}Tc-MAG3 diuretic renal scintigraphy (DRS), excretory urography (EU) and ultrasound (US) in 29 healthy piglets and in 20 piglets with surgically induced ureteric stenosis (total of 50 postoperative examination blocks). Results: MRU allowed complete depiction of the urinary tract in all controls, in operated piglets the stenosis was always correctly identified. Quality of MRU was superior to EU in 36 to 43 comparative studies. Calculation of single kidney function from parenchymal renograms, and assessment of urinary excretion from whole-kidney renograms resulted in a highly significant agreement of MRU with DRS. Conclusion: Static-dynamic MR urography allows excellent depiction of experimentally induced urinary tract obstruction, and reliable assessment of individual renal function and urinary excretion. Two advantages of the method stand out, it does not require radiation and it permits a functional-morphological correlation. (orig.) [German] Ziel: Einschaetzung der Wertigkeit der kombinierten statisch-dynamischen MR-Urographie (MRU) zur umfassenden funktionell-morphologischen Diagnostik tierexperimentell induzierter Harntransportstoerungen. Methodik: Die statisch-dynamische MRU-Kombination aus einer atemgetriggerten 3D-IR-TSE-Sequenz und einer dynamischen 2D-FFE-Sequenz nach Gd-DTPA und Furosemid - wurde im Vergleich zu {sup 99m}Tc-MAG3-Diurese-Nierenszintigraphie (DNS), Ultraschall (US) und Ausscheidungsurographie (AUG) bei 29 gesunden Ferkeln sowie bei 20 Ferkeln mit operativ indizierter Harnwegsstenose (insgesamt 50 postoperative Untersuchungsbloecke) durchgefuehrt. Ergebnisse: Die MRU

  8. Ausländerfeindlichkeit unter Jugendlichen in Leipzig

    OpenAIRE

    Petermann, Sören; Goldenberg, Olga

    2017-01-01

    In kommunalen Umfragen erhobene Einstellungen gegenüber Ausländern repräsentieren ein Bild gelebter Toleranz. Selten werden Jugendliche zu ihren ausländerbezogenen Einstellungen gefragt und mit altersspezifischen Faktoren in Verbindung gesetzt. Dieser Beitrag bezieht sich auf theoretische Ansätze der Anomietheorie, der Sozialisations- und Deprivationsforschung, um Kompensationsprozesse und Konfliktpotenziale als Wirkungsmechanismen für Ausländerfeindlichkeit unter Leipziger Jugendlichen zu un...

  9. Investigation of LPP combustors under elevated pressure conditions; Untersuchungen zu LPP-Flugtriebwerksbrennkammern unter erhoehtem Druck

    Energy Technology Data Exchange (ETDEWEB)

    Fink, R.

    2001-05-01

    The development of new combustor concepts for aero engines to meet future emissions regulations in based on a detailed knowledge of the combustion process and the velocity field. In the presented thesis, non intrusive measurements were performed in a model combustion chamber under almost realistic pressure and temperature conditions. The species OH, NO, unburned hydrocarbons and fuel droplets were detected in 2 dimensions with the Laser Induced Fluorescence (LIF). The velocity field was measured with the Particle Image Velocimetry technique (PIV). [German] Die Weiterentwicklung neuer Brennkammerkonzepte zur Erfuellung zukuenftiger Schadstoffemissionsrichtlinien erfordert genaue Kenntnisse der ablaufenden Verbrennungs- und Stroemungsvorgaenge in der Brennkammer. Bei den in der Arbeit vorgestellten Untersuchungen wurden in einer LPP-Modellbrennkammer unter annaehernd realistischen Eintrittsbedingungen die Spezies OH, NO, unverbrannte Kohlenwasserstoffe sowie noch fluessiger Brennstoff zweidimensional anhand der Laserinduzierten Fluoreszenz (LIF) nachgewiesen. Das Stroemungsfeld wurde mit Hilfe der Particle Image Velocimetry (PIV) gemessen.

  10. Schlafmedizinische Charakterisierung von Parkinson-Patienten mit Schlafattacken unter dopaminerger Therapie

    OpenAIRE

    Rethfeldt, Mira

    2006-01-01

    1999 wurden erstmals sogenannte Schlafattacken bei Parkinson-Patienten unter der Therapie mit Nonergolin-Dopaminagonisten berichtet. Später zeigten Studien, dass diese Schlafattacken unter jeglicher dopaminerger Therapie auftreten können. Bis heute ist jedoch die Pathophysiologie dieses Phänomens nicht hinreichend geklärt. Es wird diskutiert, ob diese Attacken als paroxysmales Symptom überhaupt bestehen oder nicht vielmehr ...

  11. Investigations of coal ignition in a short-range flame burner using optical measuring systems; Untersuchungen zur Kohlezuendung am Flachflammenbrenner unter Verwendung optischer Messtechnik

    Energy Technology Data Exchange (ETDEWEB)

    Hackert, G.; Kremer, H.; Wirtz, S. [Bochum Univ. (Germany). Lehrstuhl fuer Energieanlagentechnik

    1999-09-01

    The short-range flame burner and the KOALA reactor of DMT are experimental facilities for realistic simulation of coal conversion processes at high temperatures and pressures in atmospheric conditions. The TOSCA system enable measurements of temperatures, sizes, shapes and velocities of the fuel particles, which serve as a basis for a three-dimensional simulation model of coal combustion. In the future, further parameter studies will deepen the present knowledge of coal dust combustion under pressure and enable optimisation of the numerical models for simulation of industrial-scale systems for coal dust combustion under pressure. [Deutsch] Mit dem Flachflammenbrenner und dem KOALA-Reaktor der DMT stehen Versuchsapparaturen zur Verfuegung, mit deren Hilfe die Kohleumwandlungsprozesse bei hohen Temperaturen unter Druck und unter atmosphaerischen Bedingungen realistisch wiedergegeben werden. Das TOSCA-System erlaubt dabei die Bestimmung von Temperaturen, Groessen, Formen und Geschwindigkeiten der Brennstoffpartikel. Diese Daten liefern die Grundlage fuer die Erstellung eines dreidimensionalen Simulationsmodells zur Modellierung der Kohleverbrennung. In Zukunft werden weitere Parameterstudien das Verstaendnis der Kohlenstaubdruckverbrennung vertiefen und ein Optimierung der numerischen Modelle ermoeglichen, so dass die Simulation grosstechnischer Kohlenstaubdruckverbrennungsanlagen realisiert werden kann. (orig.)

  12. Damage characterisation of silicon carbides for applications in gas turbines in complex load conditions; Charakterisierung des Schaedigungsverhaltens von Siliciumcarbiden fuer den Einsatz in Gasturbinen unter komplexen Beanspruchungsbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Nestle, E.

    2000-06-01

    A tensile test facility for simultaneous thermal, mechanical and corrosive loading was developed and constructed for the purpose of characterizing the damage characteristics of ceramic high-temperature materials. Apart from tensile tests for up to 830 h, tests were also carried out on four-point bending test pieces and disk-shaped oxidation test pieces. The experiments were made at 1450 - 1550 C in dry or moist air. The materials investigated were one hot-pressed silicon carbide and two sintered silicon carbides. [German] Um keramische Hochtemperaturwerkstoffe bezueglich ihres Schaedigungsverhaltens charakterisieren zu koennen, wurde im Rahmen der vorliegenden Arbeit eine Zugpruefanlage zur gleichzeitigen Beanspruchung unter thermischen, mechanischen und korrosiven Bedingungen entwickelt und aufgebaut. Neben den in dieser Anlage durchgefuehrten Zugpruefungen mit Versuchszeiten bis zu 830 h wurden begleitende Untersuchungen an Vierpunkt-Biegeproben und scheibenfoermigen Oxidationsproben durchgefuehrt. Die Versuche konzentrierten sich auf den Temperaturbereich 1450-1550 unter trockenen und feuchten Luftatmosphaeren. Bei den untersuchten Werkstoffen handelte es sich um eine heissgepresste und zwei gesinterte Siliciumcarbid-Qualitaeten. (orig.)

  13. Messung der Respirationsverschiebung intraabdominaler Organe am Beispiel der Leber unter maschineller Ventilation

    OpenAIRE

    Olbrich, Bernhard

    2008-01-01

    Ziel dieser Arbeit ist es, die Bewegung intraabominaler Organe am Beispiel der Leber unter den Bedingungen maschineller Beatmung zu quantifizieren. Ein Messverfahren mit Hilfe eines elektromagnetischen Trackingsystems, wurde hierzu im Tierversuch neu entwickelt. Im Anschluss wurden die Messdaten mit Hilfe einer Explorativen Datenanalyse, validiert und ein einfaches Modell entwickelt, das die virtuelle Kompensation der Atemverschiebung ermöglicht. Zusätzlich wird eine praktische Anwendungsmögl...

  14. Die Analyse der Wertschöpfungskette Schweinefleisch unter den Aspekten des Supply Chain Management

    OpenAIRE

    Schönberger, Wolfgang

    2008-01-01

    Inhalt der Arbeit ist die vergleichende Analyse der Wertschöpfungskette Schweinefleisch unter den Aspekten des Supply Chain Management für Bayern sowie für Dänemark als dem weltweit größten Nettoexporteur von Schweinefleisch. Wichtige Wettbewerbsfaktoren und die Strukturen der Wertschöpfungskette werden untersucht. Die Produktionskosten werden nach der Methode der Vollkostenrechnung ermittelt. In Dänemark haben sich auf allen Stufen der Wertschöpfungskette Strukturen entwickelt, die die...

  15. Coalification reactions under pressure. Inkohl-ungsreaktionen unter Druck

    Energy Technology Data Exchange (ETDEWEB)

    Huck, G.; Patteisky, K.

    1964-12-15

    Studies of the influence of pressure on the coalification reactions in hard coal (temperature ranges from 240 to 350/sup 0/C and pressures ranging from 0.1 to 8000 ata) have shown that coalification reactions in younger coals are impeded by higher mechanical pressures. The relationship of the mutual effect of pressure and temperature on the coalification reactions may be illustrated by graphs, if the parameters are determined, which cause an increase in the reflection index of the vitrinite of 0.89 to 1.0 and liberate 8 liters of gas per kilogram of finely ground coal, at 0.5 mm Hg. The results indicate, contrary to theories often expressed in the literature, that the intensifying influence of pressure on coalification may be excluded if the pressure charge operates through shear- and friction-forces, without temperature changes. The results also show that the use of spores as coalification thermometers is limited. It is shown that at higher pressures spores may be exposed to temperatures above 200/sup 0/C without showing thermal modifications.

  16. Anforderungen an Marketingkonzepte für Großtraktoren unter Berücksichtigung des Wandels landwirtschaftlicher Rahmenbedingungen

    OpenAIRE

    Thiel, Jörg

    2017-01-01

    Beeinflusst von der Volatilität der Märkte, ergänzt um gesellschaftspolitische wie absatzorientierte Maßnahmen, ist die Landtechnikbranche seit jeher einem permanenten Wandel ausgesetzt. Insbesondere unter dem derzeit im Fokus stehenden Aspekt der Nachhaltigkeit in landwirtschaftlichen Produktionssystemen bedarf es der Gestaltung innovativer Ansätze für effizientere sowie gleichzeitig ressourcenschonende Verfahren. Zusätzlich verstärkt durch die seit geraumer Zeit anhaltend angespannten Situa...

  17. Predicting the service life of connecting rod and main bearings, taking into account different engine loads. Final report; Lebensdauervorhersage fuer Pleuel- und Hauptlager unter Beruecksichtigung unterschiedlicher Motorlastkollektive. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Berkowitz, B.; Lueneburg, B.; Liu, J.

    1994-12-31

    Connecting rod and main bearings of internal combustion engines are among the most heavily stressed components in modern engines. It was found that these engine components are increasingly reaching the limits of their strength and therefore become the components limiting engine life. However, there is no known process which makes a calculated prediction of the service life of modern connecting rod and main bearings possible, taking into account various engine loads. In this research project, a new concept for the calculated prediction of the service life of non-static highly loaded radial sliding bearings is worked out. The basis is a process of calculation which realistically determines the pressure and gap course in highly loaded sliding bearings. Apart from the viscosity depending on pressure and temperature, the elastic deformations of the system sliding bearing/conn rod are also taken into account. Calculations are done for different operating points for a complete cycle of a four stroke Diesel engine (Daimler-Benz OM 364 LA). The results are compared with the present conventional process of calculation and the effects which occur are discussed. Based on the elasto-hydrodynamic calculation, a method of calculating the service life of non-statically loaded sliding bearings, taking into account various motor loads, is worked out. (orig./HW) [Deutsch] Pleuel- und Hauptlager von Verbrennungskraftmaschinen zaehlen mit zu den spezifisch am hoechsten beanspruchten Bauteilen in modernen Motoren. Es hat sich gezeigt, dass vor allem diese Maschinenelemente zunehmend an die Grenzen ihrer Belastbarkeit stossen und so zum lebensdauerbegrenzenden Bauteil werden. Es ist jedoch kein Verfahren bekannt, das eine rechnerische Lebensdauervorhersage moderner Pleuel- und Hauptlager unter Beruecksichtigung unterschiedlicher Motorlastkollektive ermoeglicht. Im vorliegenden Forschungsvorhaben wird daher ein neuartiges Konzept zur rechnerischen Lebensdauervorhersage von instationaeren

  18. Zero-leakage shut-off butterflies for high-temperature applications; Dichtschliessende Absperrklappen fuer die Hochtemperaturtechnik

    Energy Technology Data Exchange (ETDEWEB)

    Meier, N. [Krombach Armaturen, Kreuztal (Germany)

    2000-03-01

    Over many years, zero-leakage butterfly valves have eminently proven their capabilities in a large range of elevated-temperature and elevated-pressure processes. This article examines the basic design differences between various butterfly valves. These differences are, among other factors, important indicators of the suitability of the various valve types for their use in industry. (orig.) [German] Dichtschliessende Absperrklappen haben sich ueber Jahre in vielen Prozessen, die unter hoeherem Druck und hoeherer Temperatur ablaufen, bestens bewaehrt. Der Beitrag zeigt die grundsaetzlichen konstruktiven Unterschiede dichtschliessender Absperrklappen. Diese Unterschiede sind unter anderem Indikatoren fuer die Prozesstauglichkeit von Absperrklappen in der Industrie. (orig.)

  19. Fragmentierungsarten von Nierensteinen unter extrakorporaler Stoßwellenlithotripsie: eine multivariate Analyse

    Directory of Open Access Journals (Sweden)

    Aeberli D

    1999-01-01

    Full Text Available Das primäre Ziel dieser retrospektiven Studie war die Evaluation von routinemäßig anwendbaren Kriterien, welche die Fragmentierung von Nierensteinen unter extrakorporaler Stoßwellenlithotripsie (ESWL voraussagen können. Die Serie umfaßte 202 konsekutive Patienten (121 Männer, 81 Frauen mit einem medianen Alter von 48 Jahren (19-81 Jahre, die an der Urologischen Universitätsklinik Bern mit dem originalen Dornier HM-3 behandelt wurden. Einschlußkriterien waren Einzelsteine von 10-30 mm Größe mit Lage im Nierenbeckenkelchsystem. Die Steine wurden im Abdomen-Leerbild nach ihrer Lage, Größe, Form, Dichte (im Vergleich zur 12. Rippe, Struktur und Oberfläche beurteilt. Weiter wurden Alter, Geschlecht und Body-Mass-Index des Patienten berücksichtigt. Die Desintegration wurde am 1. Tag nach ESWL mittels Abdomen-Leerbild dokumentiert. Zielwert der Analyse war die binäre Variable steinfrei versus Restfragmente, gegen die alle präoperativen Parameter mittels multivariater logistischer Regression getestet wurden. Die Erfolgsrate betrug 95,5 %; 42 Patienten (20,8 % waren steinfrei und 151 Patienten (74,7 % hatten sog. klinisch insignifikante Restfragmente (5 mm oder kleiner. Von den Männern waren 14,9 %, von den Frauen 29,6 % steinfrei (p = 0,01. Alle anderen Parameter erreichten keine statistische Signifikanz, möglicherweise aufgrund zu kleiner Subgruppen (fehlende statistische Macht. Die Desintegrationsrate des HM-3 für Nierensteine ist insgesamt ausgezeichnet, bei Frauen noch besser als bei Männern. Gerade wegen dieser hohen Erfolgsrate wären größere Patientenzahlen notwendig, um eventuelle Unterschiede zwischen den präinterventionellen Parametern definieren zu können.

  20. Modelling of in-vessel retention after relocation of corium into the lower plenum - Evaluation of the temperature field and of the viscoplastic deformation of the vessel wall. Reactor safety research, project No.:150 1254 - Final report; Beitrag zur Modellierung der Schmelzerueckhaltung im RDB nach Verlagerung von Corium in das untere Plenum - Berechnung des Temperaturfeldes und der viskoplastischen Verformung der Behaelterwand. Reaktorsicherheitsforschung, Vorhaben-Nr.: 150 1254 - Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Altstadt, E.; Willschuetz, H.G. [Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany)

    2005-01-01

    Considering the hypothetical core melt down scenario for a light water reactor (LWR) a possible failure mode of the reactor pressure vessel (RPV) and its failure time has to be investigated for a determination of the loadings on the containment. Several experiments have been performed accompanied with material properties evaluation, theoretical, and numerical work. At the Institute Of Safety Research of the FZR a finite element model has been developed simulating the thermal processes and the viscoplastic behaviour of the vessel wall. An advanced model for creep and material damage has been established and has been validated using experimental data. The thermal hydraulic and the mechanical calculations are sequentially and recursively coupled. The model is capable of evaluating fracture time and fracture position of a vessel with an internally heated melt pool. The model was applied to pre- and post test calculations for the FOREVER test series representing the RPV of a PWR in the scale of 1:10. These experiments were performed at the Royal Institute of Technology in Stockholm. The results of the calculations can be summarised as follows: The creeping process is caused by the simultaneous presence of high temperature (>600 C) and pressure (>1 MPa). The hot focus region is the most endangered zone exhibiting the highest creep strain rates. The exact level of temperature and pressure has an influence on the vessel failure time but not on the failure position. The failure time can be predicted with an uncertainty of 20 to 25%. This uncertainty is caused by the large scatter and the high temperature sensitivity of the viscoplastic properties of the RPV steel. Contrary to the hot focus region, the lower centre of the vessel head exhibits a higher strength because of the lower temperatures in this zone. The lower part moves down without significant deformation. Therefore it can be assumed, that the vessel failure can be retarded or prevented by supporting this range. The

  1. "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...

  2. Static and dynamic magnetic properties of CoPt{sub 3}. Nanoparticles in comparison with bulk matter; Statische und dynamische magnetische Eigenschaften von CoPt{sub 3}. Nanopartikel im Vergleich zum Volumenmaterial

    Energy Technology Data Exchange (ETDEWEB)

    Raeder, C.

    2006-09-22

    In this work the structural and magnetic characteristics of CoPt{sub 3}-particles are examined. In particular the determination of the g-factor is of interest as well as the damping behavior of the magnetization vector under influence of a microwave radiation. Moreover the magnetic anisotropy energy density of individual particles is covered by the presented thesis. The particles exist in the chemically disordered phase. They are monocrystalline and monodisperse with a mean diameter of d=4.04 nm and a width of the size distribution of {sigma}=0.15, as determined by transmission electron microscopy. Moreover the particles are embedded into a polymer with high dilution (0.08 vol%). To compare the results for the particles CoPt{sub 3} films and bulk-material are prepared and examined with the same procedure. X-ray diffraction (XRD) shows that all three sample systems are an alloy and do not appear as cobalt clusters embedded in platinum. The lattice constant of the particles is increased by 0.5% in comparison to the bulk material (a{sub NP}=0.388{+-}0.003 nm). The evaluation of the peak widths of the XRD experiments exhibit a crystalline size of 95.5{+-}6.5 nm of the films and 48.5{+-}6.5 nm of the bulk material. The evaluation of the relative intensities of (111)- and (200)-peaks points the fact that both the film and the particles preferentially grow in the (111)-direction. The films are polycrystalline in the film-plane. From magnetic resonance measurements the g-factor and the damping constant {alpha} is extracted. The measurement shows that both the g-factor (about 2%) and the damping-constant {alpha} (about 125%) is increased in comparison to the film, and/or bulk material. For the films M{sub eff} is determined from angle-dependent resonance-field measurements. From the temperature dependence of the resonance field the magnetic anisotropy is determined. Because of the fact that the measurements could be done only to a minimum of 50 K the value of the anisotropy

  3. Rigiscan®-Monitoring der Erektion unter audiovisueller sexueller Stimulation ohne/mit Viagra™ bei Patienten mit erektiler Dysfunktion

    Directory of Open Access Journals (Sweden)

    Perabo FGE

    2000-01-01

    Full Text Available Die orale Medikation mit Sildenafil (Viagra™ hat sich zur Therapie der erektilen Dysfunktion etabliert und relativiert die Differentialdiagnose zwischen psychogener und organischer Dysfunktion mit den entsprechenden therapeutischen Konsequenzen. Diesem Problem widmet sich diese Studie zur Prüfung der erektilen Antwort unter RigiScan®-Monitoring ohne/mit 50 mg Viagra™. 64 Patienten (mittleres Alter 48 Jahre mit einer erektilen Dysfunktion arteriogener (n = 10, venöser (n = 7, gemischt neurogen/vaskulärer (n = 15 und psychogener (n = 32 Genese von mehr als 6 Monaten Dauer wurden in die Studie aufgenommen. Alle Patienten wurden eingehend diagnostisch abgeklärt, inklusive Hormonlabor, dynamischer Pharmako-Duplexsonographie und, falls indiziert, mit einer Cavernosometrie/ -graphie. Zur Testung der penilen Rigidität und zur Objektivierung der Erektion wurde das "real-time" RigiScan® verwendet. In zwei konsekutiven Messungen wurden sowohl die direkte erektile Antwort auf visuelle Stimulation als auch die nächtlichen Erektionen abgeleitet und die Meßergebnisse mit den Begleiterkrankungen, "lifestyle"-Faktoren und dem Ergebnis der Pharmako-Duplexsonographie korreliert. Es fand sich keine Korrelation zwischen der Ätiologie der erektilen Dysfunktion in bezug auf organische oder psychogene Genese und dem Alter der Patienten, der Dauer der Erektionsstörung, dem Nikotinabusus, den Blutfetten, den Testosteronwerten, dem klinischen Ergebnis der Pharmakotestung (Erektionsgrad und dem duplexsonographisch gemessenen Fluß der penilen Arterien. Hingegen zeigte sich eine positive Korrelation zwischen Genese der erektilen Dysfunktion (organisch bzw. psychogen und dem RigiScan®-Meßergebnis (r = 0,29. Patienten mit psychogen bedingter Erektionsstörung profitierten am meisten von Viagra™, während Patienten mit vaskulärer Genese oder gemischt neurogener/vaskulärer Genese deutlich schlechter auf Viagra™ ansprachen. Es bestand keine Korrelation

  4. Zu entwicklungstendenzen im satzbau der Deutschen sprache der gegenwart unter besonderer Berücksichtigung der ausrahmung

    Directory of Open Access Journals (Sweden)

    Jasna Makovec

    1983-01-01

    Full Text Available Die vorliegende Arbeit wurde durch das Bestreben motiviert, weitere Ergänzungen zum Phänornen "Ausrahrnung in der modernen deutschen Schriftsprache der Gegenwart" zu leisten. Der Ausgangspunkt dieses "fakultativ" geregelten Bereiches ist die Annahme bzw. die Arbeitshypothese, daß sich linguistische und außerlinguistische Faktoren einander zuordnen lassen. Das bedeutet, daß die Linearität innerhalb des Kornrnunikationspro­ zesses auch einige wichtige kommunikative Funktionen auszuüben hat, und daß die kontextuellen Modifikationen der Stellungsva­ rianten bei gleichern Denotatsbezug unter diesern Blickwinkel untersucht werden müssen, und nicht gleich als stilistische Varianten qualifiziert werden.

  5. Mechanical-biological waste treatment with thermal processing of partial fractions; Mechanisch-biologische Restabfallbehandlung unter Einbindung thermischer Verfahren fuer Teilfraktionen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    Technologies for mechanical-biological treatment of waste in the Land of Hessen were compared including thermal processes like combustion and gasification. The new and more rigid limiting values specified in the Technical Guide for Municipal Waste Treatment (Technische Anleitung Siedlungsabfall - TASI) get a special mention. [Deutsch] Verschiedene Technologien der mechanisch-biologischen Restabfallbehandlung im Raum Hessen wurden unter Einbezug thermischer Verfahren (Verbrennung, Vergasung) miteinander verglichen. Dabei wurden besonders auf die verschaerften Grenzwerte der Technischen Anleitung Siedlungsabfall (TASI) eingegangen. (ABI)

  6. Alkali release and sorption during combustion and gasification of coal under pressure; Freisetzung und Einbindung von Alkalien bei der Verbrennung und Vergasung von Kohle unter Druck

    Energy Technology Data Exchange (ETDEWEB)

    Steffin, C.R.; Wanzl, W.; Heek, K.H. van [DMT-Gesellschaft fuer Forschung und Pruefung mbH, Essen (Germany). Geschaeftsbereich FuelTec - Kokerei- und Brennstofftechnik

    1999-09-01

    Investigations and model calculations have shown that water-soluble alkaline substances (in German coal, mostly NaCl) are released by a desorption process rather than a purely physical evaporation process. Sorption takes place in the presence of reactive oxygen species (H{sub 2}O or O{sub 2}), but only the reaction with water vapour is applicable to technical processes. Soorption is preferred to desorption at low temperatures both kinetically and thermodynamically. Metakaolin has a high alkali sorption capacity and potential depending significantly on the chemical properties of the clay mineral. With increasing basicity, the sorption potential decreases drastically, which has a significant effect in terms of fuel selection and mode of operation of the process of coal dust combustion under pressure. A fuel with low alkali emissions would be a coal grade with a small fraction of water-soluble alkalis and a high fraction of acid clay minerals. Intensive scrubbing in a wet chemical treatment stage may serve to reduce the water-soluble alkalis. [Deutsch] Die Untersuchungen und Modellrechnungen haben gezeigt, dass die Freisetzung der wasserloeslichen Alkalien, was in deutschen Steinkohlen hauptsaechlich NaCl ist, ein Desorptionsmechanismus zugrunde liegt und die Vorstellung eines rein physikalischen Verdampfungsprozesses verworfen werden muss. Die Einbindung der Alkalien findet unter Teilnahme reaktiver Sauerstoffspezies (H{sub 2}O oder O{sub 2}) statt, wobei aber nur die Reaktion mit Wasserdampf auch auf technische Prozesse uebertragbar ist. Die Einbindung ist gegenueber der Desorption bei niedrigen Temperaturen kinetisch und thermodynamisch bevorzugt. Metakaolin besitzt eine hohe Kapazitaet und ein hohes Potential zur Einbindung von Alkalien, wobei die Faehigkeit zur Einbindung ganz entscheidend von den chemischen Eigenschaften des Tonminerals abhaengig ist. Mit steigender Basizitaet nimmt das Einbindungspotential der Mineralsubstanz drastisch ab. Das hat auch

  7. 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.

  8. Pressure vessel failure at high internal pressure; Untersuchungen zum Versagen des Reaktordruckbehaelters unter hohem Innendruck

    Energy Technology Data Exchange (ETDEWEB)

    Laemmer, H.; Ritter, B.

    1995-08-01

    A RPV failure due to plastic instability was investigated using the ABAQUS finite element code together with a material model of thermal plasticity for large deformations. Not only rotational symmetric temperature distributions were studied, but also `hot spots`. Calculations show that merely by the depletion of strength of the material - even at internal wall temperatures well below the melting point of the fuel elements of about 2000/2400 C - the critical internal pressure can decrease to values smaller than the operational pressure of 16 Mpa. (orig.)

  9. Optimisation of a truck diesel engine with a view to environmental pollution. Interstate research project. Final report; Optimierung eines mit Rapsoelmethylester betriebenen Nutzfahrzeug-Dieselmotors unter besonderer Beruecksichtigung der Umweltvertraeglichkeit. Laenderuebergreifendes Verbundforschungsvorhaben. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Hattingen, U.; Adt, H.U. [Kaiserslautern Univ. (Germany). Arbeitsgruppe Verbrennungskraftmaschinen; Sauer, B.; Ruhl, C.; Huber, M. [Kaiserslautern Univ. (Germany). Lehrstuhl fuer Maschinenelemente und Getriebetechnik; Regitz, M.; Weber, B. [Kaiserslautern Univ. (Germany). Lehrstuhl fuer Organische Chemie; Bereswill, S. [Motoren-Werke Mannheim AG (Germany); Luther, R.; Acker, I. [Fuchs Mineraloelwerke GmbH, Eschweiler (Germany)

    1999-05-01

    Detailed rheological analyses of lubricants are carried out with a view to the temperature dependence of the viscosity functions. Two sliding bearings of similar design but made of different materials were tested on a test bench after lubrication with an oil of the SAE grade 10W-40 diluted with increasing concentrations of rapeseed oil methyl ester. The results were analyzed and compared with the bearings characteristics calculated according to DIN 31652. The measurements were found to be in good agreement with calculated values. [German] Im Rahmen dieses Projektes wurden zunaechst detaillierte rheologische Untersuchungen der Schmierstoffeigenschaften unter Beruecksichtigung der Schmieroelverduennung mit RME und DK vorgenommen und die Temperaturabhaengigkeit der jeweiligen Viskositaetsfunktion ermittelt. Auf einem geeigneten Gleitlagerpruefstand wurden zwei bezueglich der Motorenhauptlager geometrisch aehnliche Lager unterschiedlichen Werkstoffes untersucht. Die Schmierung erfolgte dabei mit einem Motorenoel der SAE-Klasse 10W-40, welches zuvor jeweils mit einem im Verlauf der Versuchsreihe ansteigenden Anteil an Rapsoelmethylester verduennt wurde. Die Messergebnisse wurden ausgewertet und den nach DIN 31652 berechneten Lagerkennzahlen gegenuebergestellt. Danach ergeben sich fuer die gemessenen Lagerkenngroessen qualitativ aehnliche Abhaengigkeiten von der Schmieroelverduennung wie berechnet. (orig.)

  10. Kontrastmittelverstärkte Magnet-Resonanz-Urographie unter forcierter Diurese - Stellenwert in der Differentialdiagnostik bei Obstruktionen des oberen Harntraktes

    Directory of Open Access Journals (Sweden)

    Jung P

    2001-01-01

    Full Text Available Die Magnet-Resonanz-Urographie (MRU ist ein relativ neues Verfahren in der Diagnostik des oberen Harntraktes. Das Ziel dieser Studie war der Vergleich der Aussagefähigkeit der MRU unter Gabe von Gadolinium und Furosemid und dem konventionellen Urogramm (IVU in der Diagnostik der Ursache von Obstruktionen im Bereich des Harnleiters. 82 Patienten mit im IVU nachgewiesener Obstruktion des oberen Harntraktes oder urographisch stummer Niere bei sonographisch nachgewiesener Dilatation wurden der MRU zugeführt. Die Bilder beider Untersuchungsmethoden wurden von voneinander unabhängigen Untersuchern befundet. Zwei Urologen befundeten die IVU-Bilder, zwei Radiologen die MRU-Bilder, die Radiologen kannten die IVU-Diagnose nicht. Bei unklarer Diagnose wurden weitere Untersuchungen wie Computertomographie, retrograde Pyelographie oder Ureteroskopie durchgeführt. Die Diagnosen waren: Harnleitersteine bei 72 Patienten, Harnleitertumore bei 8 Patienten und extraureterale Tumore bei 2 Patienten. Eine richtige Diagnose bei den Steinpatienten wurde durch IVU bei 49 von 72 Patienten und durch MRU bei 64 von 72 Patienten gestellt. In dieser Patientengruppe wurden durch die MRU zwei falsche Diagnosen gestellt. Fehlende Kontrastmittelausscheidung war der Hauptgrund für Versagen der IVU. 3 der 8 Patienten mit Harnleitertumoren wurden durch die IVU richtig dignostiziert, bei dreien wurde eine falsche Diagnose gestellt. Durch die MRU konnten in dieser Gruppe 7 von 8 Patienten korrekt diagnostiziert werden, es wurde keine falsche Diagnose erhoben. IVU wird zunächst die Standarduntersuchungstechnik zur Darstellung des oberen Harntraktes bleiben, aber durch diese Studie konnte die Möglichkeit gezeigt werden, die in der MRU in Kombination mit Gadolinium und Furosemid liegt. Die größte Bedeutung dieser Untersuchung liegt in der urographisch stummen Niere, bei Untersuchungen in der Schwangerschaft, bei Kindern und bei Patienten mit Kontrastmittelunverträglichkeit.

  11. Treibhausgasemissionen unter Bewässerung und unterschiedlicher Stickstoffdüngungsintensität auf einem Sandboden in Nord-Ost-Deutschland

    OpenAIRE

    Trost, Benjamin

    2015-01-01

    Ziel der Arbeit ist die Gesamtbilanzierung der Treibhausgasemissionen eines Anbausystems unter Bewässerung auf einem Sandboden. Die dazu aufgestellte Treibhausgasbilanz basiert auf langjährigen Datenreihen zu Erträgen und Corg-Vorräten eines Dauerfeldversuchs sowie auf zweijährigen im Feldversuch durchgeführten N2O-Messungen. Die durchgeführten Untersuchungen zum Einfluss der Bewässerung auf die Corg-Vorräte zeigen, dass der Einsatz von mineralischem Stickstoffdünger und Bewässerung auf einem...

  12. A laser-based study of kerosine evaporation and -mixing for lean prevaporized combustion at elevated pressure; Lasermesstechnische Untersuchung der Kerosinverdampfung und -mischung fuer die magere Vormischverbrennung unter erhoehtem Druck

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, M.

    1999-05-01

    The evaporation and mixing of a kerosine spray in the turbulent airstream of a prevaporizer is investigated at conditions prevailing in the combustion chamber of gas turbines. An experiment is described that allows to study an evaporating fuel spray downstream a prefilming airblast atomizer with Phase-Doppler anemometry, laser-induced fluorescence and an infrared light absorption technique. At an air pressure of 9 bars, an air temperature of 750 K, a mean air velocity of 120 m/s and a fuel flow rate of 1 g/s the kerosine spray evaporates completely without autoignition. At this operating condition the parameters air pressure, air temperature and air turbulence are varied. The influence of these parametric variations on the dropsize distribution, the evaporation rate and the concentration profiles of liquid and evaporated fuel is presented and discussed. (orig.) [German] Die Verdampfung und Vermischung eines Kerosinsprays in der turbulenten Luftstroemung eines Vorverdampfers wird unter Bedingungen untersucht, die in Brennkammern fuer Gasturbinen vorherrschen. Ein Experiment wird vorgestellt, welches es erlaubt, ein verdampfendes Kraftstoffspray stromab eines ebenen Luftstromzerstaeubers mit Filmleger mittels der Phasen-Doppler-Anemometrie, Laser-induzierter Fluoreszenz und einer Infrarotabsorptionsmesstechnik zu untersuchen. Bei einem Luftdruck von 9 bar, einer Vorwaermetemperatur der Luft von 750 K, einer mittleren Luftgeschwindigkeit von 120 m/s und einem Kraftstoffmassenstrom von 1 g/s verdampft das Kerosinspray vollstaendig, ohne die Selbstzuendungszeit zu erreichen. Bei dieser Betriebsbedingung werden die Parameter Luftdruck, Lufttemperatur und Turbulenzgrad variiert. Der Einfluss dieser Parameter auf das Tropfengroessenspektrum, den Verdampfungsgrad und die Konzentrationsprofile des fluessigen sowie des verdampften Kraftstoffs wird dargestellt und diskutiert. (orig.)

  13. Investigation of hydrogen recombination under natural convection conditions; Untersuchungen zur Wasserstoffrekombination unter Naturkonvektionsbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Berno

    2015-09-04

    Passive Autocatalytic Recombiners (PAR) are installed inside the containment of nuclear power plants in order to prevent the build-up of flammable mixtures and to mitigate the effects of hydrogen deflagrations, which can occur in the event of a severe accident combined with the release of hydrogen. In order to simulate the operating behaviour of PARs, the computer program REKO-DIREKT is being developed at the Forschungszentrum Juelich in collaboration with the Institute for Reactor Safety and Reactor Technology at the RWTH Aachen. For the validation of the code, data from experimental facilities operated at Juelich are used. This work focusses on the analysis of the chimney effect through the PAR housing as well as the optimization of the chimney model of REKO-DIREKT. Therefore experimental investigations are carried out in the REKO-4 facility under natural convection conditions. This facility is equipped with numerous measuring devices, e.g. katharometers for in-situ measuring of the hydrogen concentration and the optical flow measurement technique Particle-Image-Velocimetry. In preliminary assessments the equipment is being qualified in order to determine the measurement accuracy. In the following experimental investigations, a small-scale PAR is used, that is built in a modular way allowing it to be equipped with different chimney geometries. The experimental results produce a database that shows the central correlation between the hydrogen concentration, the catalyst temperature and the inlet velocity. The results include the variation of the recombiner's chimney height and experiments at different operating pressures. After optimization of the chimney model, the simulation program is validated against experiments in the large-scale facility THAI in Eschborn, which have been performed subsequent to this thesis in the context of the OECD/NEA-THAI project. Finally, the influence of a downward-directed, near-wall flow on the operational behaviour of the small

  14. Carbon dioxide digital subtraction angiography using a new gas management system; Digitale Subtraktionsangiographie mit Kohlendioxid unter Verwendung eines neuen Gasdosiersystems

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz-Rode, T.; Alzen, G.; Guenther, R.W. [Klinik fuer Radiologische Diagnostik, Universitaetsklinikum der RWTH Aachen (Germany)

    1997-07-01

    Purpose: The clinical evaluation of digital subtraction angiography with carbon dioxide using a newly developed low-tech CO{sub 2}-dosage- and injection system. Method and patients: The hand-held system (CO{sub 2} angio set) consists of a dosage chamber in connection with a special stopcock to apportion the gas. By optimising injection volume and pressure steady gas flow characteristics are approximated. A safety design prevents unintentional gas injection volume and pressure steady gas flow characteristics are approximated. A safety design prevents unintentional gas injection. CO{sub 2} arteriographies were performed on 185 patients. Main indications were renal insufficiency and a history of adverse reactions to iodinated contrast media. In patients with femoral connula access, catheterless reflux angiography was performed. Results: The injection system provided complete and coherent visualisation of the abdominal aorta, visceral, pelvic, and lower limb arteries via catheter (71 cases) or via femoral cannula using reflux technique (114 cases). Stenoses, occlusions, and collaterals were assessable. Employing the gas reflux over the aortic bifurcation bilateral run-off studies up to the calf trifurcation were performed via unilateral femoral cannula. Use of a dedicated stacking software improved image quality of distal femoral, popliteal and calf arteries. Conclusion: The CO{sub 2} management system allows adequate imaging of the arteries below the diaphragm. Ease and safety of use and low costs are advantageous. (orig.) [Deutsch] Ziel: Die klinische Erprobung der digitalen Subtraktionsangiographie mit Kohlendioxid unter Verwendung eines neuentwickelten, einfachen Gasdosier- und Injektionssystems. Methode und Patienten: Eine Dosierkammer mit einstellbarem Volumen in Verbindung mit einem Spezial-Hahn (CO{sub 2}-Angio-Set) portioniert das Gas. Durch Optimierung von Injektionsvolumen und -druck wurde eine konstante Ausstroemcharakteristik angenaehert. Das System wurde

  15. Ein (neuer Blick auf die Konkurrenz unter Frauenforscherinnen A (New Look at Competition Among Women Scholars in Women’s Studies

    Directory of Open Access Journals (Sweden)

    Anina Mischau

    2002-07-01

    Full Text Available Die Solidarität unter Frauenforscherinnen wird bis heute als politisch-ideologisches Postulat der Frauenforschung aufrechterhalten, obwohl im Zuge einer zunehmenden Institutionalisierung und Professionalisierung bei einer gleichzeitig nahezu unveränderten Marginalisierung der Frauenforschung an deutschen Hochschulen eine stärker werdende Konkurrenz auch unter Frauenforscherinnen zu beobachten ist. Sünne Andresen geht der Frage nach den möglichen Ursachen von Konkurrenz unter Frauenforscherinnen in der Hochschule nach. Diese Fragestellung ist in der Frauen- und Geschlechterforschung nicht neu, wenngleich sie bislang eher allgemein auf die Konkurrenz unter Wissenschaftlerinnen bezogen worden ist. Innovativ ist jedoch, dass die Autorin hierfür den subjektwissenschaftlichen Ansatz der Kritischen Psychologie und die Habitus-Feld-Konzeption Bourdieus als theoretischen Bezugsrahmen auswählt und damit deutlich über die vorherrschenden subjektzentrierten oder strukturtheoretischen Erklärungsansätze hinausgeht. Die empirische Basis ihrer Studie sind sechs qualitative Interviews mit Habilitandinnen der geistes- und sozialwissenschaftlichen Fächer, die sich auf die Frauen- und Geschlechterforschung spezialisiert haben. Insgesamt arbeitet die Autorin interessante Aspekte möglicher Ursachen des Konkurrenzverhaltens unter und der Konkurrenzerfahrungen von Frauenforscherinnen heraus. Sie bleibt der Leserin aber mindestens genauso viele Antworten schuldig, wie sie durch die dargestellten „empirischen Ergebnisse" zu geben vermag.Until the present day, solidarity among feminist scholars is upheld as an ideological-political postulate in this particular scholarly community. These views continue to be upheld despite the increasing institutionalisation and professionalisation of research in women’s studies research. These institutional changes result in an increased sense of competition among feminist scholars, while women’s studies continue to

  16. Islands sinking; Land unter

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, Joerg-Rainer

    2013-04-15

    The urbanization is a global trend. Today, 22 of the 30megacities, each with more than 10 million inhabitants, are located in developing countries and emerging countries. These megacities consume the most electricity: About two-thirds of the global consumption of electricity and heat are consumed in megacities. At the same time, the prosperity is concentrated in monopolies: In the last 50 years, the per capita income of the urban population has increased by about 150 %. The productivity of urban areas increases. Thus, cities are of central importance to our culture. If global warming is not stopped, climate change hits them with full force.

  17. Ironieentwicklung unter interaktionslinguistischer Perspektive

    OpenAIRE

    Kotthoff, Helga

    2007-01-01

    Der vorliegende Aufsatz gibt Einblick in ein Pilotprojekt zur Entwicklung von Ironie und vergleichbaren Formen der Kommunikation einer Bewertungskluft in Interaktionssituationen mit Schulkindern. Um Ironie zu verstehen, muss man davon ausgehen, dass Äußerungen verschiedene Bedeutungsschichten haben können. Man kann diesem Typus indirekten Sprechens nur Sinn zuordnen, wenn man generelle Haltungen des Sprechers inferieren kann, und diese Haltung dann gleichzeitig zum Ausgangspunkt nimmt, auch s...

  18. Visusminderung unter Silikon

    DEFF Research Database (Denmark)

    Dornonville de la Cour, Morten; Lux, Anja; Heegaard, Steffen

    2010-01-01

    Silicone oil is used as intravitreal tamponading agent in surgery for rhegmatogenous retinal detachment (RRD) cases complicated with proliferative vitreoretinopathy (PVR). Recently, a number of case series have appeared where profound central visual loss has been found in eyes after uncomplicated...... vitrectomy with silicone tamponade for RRD in eyes with seemingly good visual potential. Several reports have demonstrated the migration of silicone oil droplets into the retina and the optic nerve, others the widespread loss of myelinated optic nerve fibres. These reports are reviewed, and it is concluded...... that caution is warranted when silicone oil is used in eyes with good visual potential. Finally the additional danger of central visual loss should be taken into consideration when deciding to use silicone oil or gas as intravitreal tamponade....

  19. Numerical simulation of spatial whole-body vibration behaviour of sitting man taking into account individual anthropometry and position; Numerische Simulation des raeumlichen Ganzkoerperschwingungsverhaltens des sitzenden Menschen unter Beruecksichtigung der individuellen Anthropometrie und Haltung

    Energy Technology Data Exchange (ETDEWEB)

    Pankoke, S.

    2003-07-01

    A dynamic FE model of the anatomy of humans in sitting position is presented for assessing the dynamic internal response of the human body to the effect of external vibrations. The model can be adapted to individual body measures, different positions and different spatial orientation. It was verified on the basis of extensive measured data. The problem of contact between the human body and the driver seat is solved by a simplified static description. The model comprises a sub-model of the lumbar vertebral column for assessing the spatial load distributions in this body region. [German] In der vorliegenden Arbeit wird ein dynamisches, an der menschlichen Anatomie orientiertes Finite-Elemente-Modell des sitzenden Menschen vorgestellt, das es gestaltet, dynamische innere Antworten des Koerpers auf von aussen auf den Menschen einwirkende Schwingungen zu ermitteln. Das Modell ist ueber eine Auswahl anthropometrischer Masse an das Schwingungsverhalten eines Individuums anpassbar und ermoeglicht zudem die Simulation von Schwingungseinwirkungen in unterschiedlichen Haltungen und in allen Raumrichtungen. Die Modellverifikation erfolgte an umfangreichen Messdatenbestaenden. Das Kontaktproblem des Menschen zum Fahrzeugsitz ist durch eine vereinfachte statische Beschreibung abgebildet. Ferner beinhaltet das Ganzkoerpermodell ein Submodell der Lendenwirbelsaeule, mit dessen Hilfe die aus den Ganzkoerperschwingungen folgenden raeumlichen Beanspruchungsverteilungen in der Lendenwirbelsaeule ermittelt werden koennen. (orig.)

  20. Dynamic oxygen transfer measurements under operating conditions as a basis for the optimization of ventilation systems; Dynamische Sauerstoffeintragsmessungen unter Betriebsbedingungen als Grundlage zur Optimierung von Belueftungssystemen

    Energy Technology Data Exchange (ETDEWEB)

    Libra, J.A.; Biskup, M.; Wiesmann, U. [Technische Univ. Berlin (Germany). Inst. fuer Verfahrenstechnik; Sahlmann, C.; Gnirss, R. [Berliner Wasserbetriebe, Berlin (Germany)

    1999-07-01

    The largest single energy consumer at sewage treatment plants is the ventilation system of activated sludge tanks. This is why controlling and optimizing ventilation systems is the most appropriate approach to the cutting down of energy costs. The present paper reports on measurements of dynamic oxygen transfer by means of the off-gas method under operating conditions at the Berlin-Ruhleben sewage treatment plant. (orig.) [German] Der groesste Einzelenergieverbraucher auf Klaerwerken ist das Belueftungssystem von Belebungsbecken. Deshalb ist die Kontrolle und Optimierung der Belueftungssysteme der geeignete Weg zur Verringerung der Energiekosten. In diesem Beitrag wird ueber Messungen des dynamischen Sauerstoffeintrags mit der Abluft-Methode unter Betriebsbedingungen im Klaerwerk Berlin-Ruhleben berichtet. (orig.)

  1. Harmonisation of fire testing of conveyor belts for underground applications within the EC; Harmonisierung der brandtechnischen Pruefverfahren von Foerdergurten fuer den Einsatz unter Tage innerhalb der EG

    Energy Technology Data Exchange (ETDEWEB)

    Foit, W. [DMT-Gesellschaft fuer Forschung und Pruefung mbH, Dortmund (Germany). Fachstelle fuer Brand- und Explosionsschutz unter Tage - Versuchsgrube Tremonia

    1998-12-01

    The mining countries of the EC still have different regulations for fire testing of conveyor belts. The test methods will be harmonized for the Common Market, and requirements on conveyor belts will be standardized within the EC. A new EC standard will be drawn up. [Deutsch] Zur Zeit sind in den bergbaubetreibenden Laendern der EG noch unterschiedliche Verfahren zur brandtechnischen Pruefung von Foerdergurten vorgeschrieben. Mit dem Inkrafttreten des Gemeinsamen Marktes und der damit zusammenhaengenden Forderung nach Abbau von Handelshemmnissen sollen diese Pruefverfahren harmonisiert werden. Ziel ist es, die an die Foerdergurte zu stellenden brandtechnischen Anforderungen innerhalb der EG zu vereinheitlichen. Es soll deshalb eine europaeische Norm zur Beurteilung des Brandverhaltens und der Brandausbreitung an Foerdergurten fuer den Kohlenbergbau unter Tage erstellt werden. (orig./MSK)

  2. [Dimitri Steinke: Die Zivilrechtsordnungen des Baltikums unter dem Einfluss ausländischer, insbesondere deutscher Rechtsquellen. (Osnabrücker Schriften zur Rechtsgeschichte, Bd. 16.) V&R unipress. Göttingen 2009. 243 S. ISBN 978-3-89971-573-6] / M

    Index Scriptorium Estoniae

    Luts-Sootak, Marju, 1966-

    2011-01-01

    Arvustus: Dimitri Steinke. Die Zivilrechtsordnungen des Baltikums unter dem Einfluss ausländischer, insbesondere deutscher Rechtsquellen. (Osnabrücker Schriften zur Rechtsgeschichte ; 16). Göttingen, 2009

  3. Hydrogen diffusion into fatigue cracks of aluminium alloy 6013 in a corrosive environment; Wasserstoffeinlagerung an Ermuedungsrissen der Aluminiumlegierung 6013 unter korrosiver Umgebung

    Energy Technology Data Exchange (ETDEWEB)

    Lenk, Christian Alexander

    2009-08-13

    The author attempted a time-resolved detection of raised hydrogen concentrations in the plastic deformation region of fatigue cracks in an aluminium test piece deformed by cyclic stress in a corrosive environment. Mechanical material parameters like the crack propagation velocity under cyclic stress change dramatically in a corrosive environment. This is assumed to be caused by hydrogen diffusion, but so far there is no method that reliably measures additional hydrogen from the corrosive environment. For this reason, a special analytical configuration was set up which makes use of the thermal desorption method. First, chips with a thickness of about 20 micrometers are sawed out of the test specimen in high-vacuum conditions. The chips fall into a hot melting vessel in a UHV chamber, where the hydrogen contained in the chips is released. The resulting pressure increase is recorded by a mass spectrometer. A hydrogen profile of the test specimen is obtained by assigning the chip position to the signal. For the corrosive medium in which the test specimen is immersed during crack initiation, i.e. NaCl solution, heavy water was used. This makes it possible to distinguish between the hydrogen contained in a piece of technical aluminium alloy (AA6013) and the deuterium diffusing in from the corrosive fluid. The deuterium is found exclusively in the test piece volume in the strongly plastically deformed region surrounding the fatigue crack. (orig.) [German] Das Ziel der vorliegenden Arbeit besteht im ortsaufgeloesten Nachweis einer erhoehten Wasserstoffkonzentration im plastisch deformierten Bereich von Ermuedungsrissen einer unter korrosiver Umgebung zyklisch verformten Aluminiumprobe. Mechanische Materialparameter wie z.B. die Rissausbreitungsgeschwindigkeit unter zyklischer Belastung aendern sich drastisch in korrosiver Umgebung. Als Ursache fuer dieses Verhalten wird eine Eindiffusion von Wasserstoff vermutet, jedoch gibt es bisher keine Messung die den zusaetzlichen

  4. Room temperature fatigue behaviour of a normalized steel SAE 4140 in torsion. Ermuedungsverhalten von normalisiertem 42CrMo4 unter Torsionsbeanspruchung bei Raumtemperatur

    Energy Technology Data Exchange (ETDEWEB)

    Klumpp, S.; Eifler, D.; Macherauch, E. (Karlsruhe Univ. (T.H.) (Germany, F.R.). Inst. fuer Werkstoffkunde 1)

    1990-05-01

    Cyclic deformation behaviour of a normalized steel SAE 4140 in shear strain-controlled torsion is characterized by cyclic softening and cyclic hardening. If mean shear stresses are superimposed to an alternating shear stress, cycle-dependent creep occurs, and the number of cycles to failure decreases. In shear strain-controlled torsional loading, mean stresses are observed to relax nearly to zero within a few cycles. Fatigue life is not influenced by mean shear strains. (orig.).

  5. Magneto-optical measurements on high-temperature superconductors influenced by AC-fields; Magnetooptische Untersuchungen an Hochtemperatursupraleitern unter Einfluss von Frequenzfeldern

    Energy Technology Data Exchange (ETDEWEB)

    Che' Rose, Simon

    2007-01-15

    In this work magneto-optical measurements on YBa{sub 2}Cu{sub 3}O{sub 7-x} and MgB{sub 2} thin films were done. For YBCO the influence of AC-pulses on the flux and current density of a thin film with transport current was investigated. For MgB{sub 2} the influence of AC-fields on the homogenous and dendritic flux penetration was researched. (orig.)

  6. Presentation of the Well Tractor Concept and practical experience in extreme conditions; Vorstellung des Well Tractor Konzepts mit Erfahrungen bei Einsaetzen unter Extrembedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Kater, H.; Preiss, F. [Preussag Wireline- und Messservice, Edemissen (Germany)

    1998-12-31

    So-called extended reach boreholes with horizontal sections of more than 2000 m, short radius drilling, multilaterals and other variations are common enough. Problems occur when this type of borehole needs to be surveyed or modified. The contribution describes the newly developed ``Well Tracotor{sup circledR}`` technology and outlines its potential. (orig.) [Deutsch] Sogenannte Extended Reach Bohrungen mit Horizontalsektionen von mehr als 2.000 Meter Laenge, Short Radius Drilling, Multilaterals und andere Variationen sind bohrtechnisch einwandfrei durchfuehrbar und gehoeren zum gaengigen Repertoire der Bohrfirmen. Grosse Probleme entstehen jedoch wenn dieser Bohrungstyp vermessen, komplettiert oder aufgewaeltigt werden soll. Insbesondere Bohrlochmessfirmen haben es in den letzten ca. 20 Jahren versaeumt Innovationen zwecks oekonomischen Einsatzes ihrer Technologie in diesen Bohrungen bereitzustellen. Die Durchfuehrung von Perforationen und Bohrlochmessungen, das Setzen von Stopfen, Schneiden von Rohren und auch einfachste Slickline-Operationen sind bei einer Bohrlochneigung beginnend bei ca. 60 bis 80 nur unter Anwendung von kosten- und zeitintensiven Verfahren moeglich. Eine guenstige Alternative zu diesen Verfahren bietet der Well Tractor. Diese Technologie ermoeglicht das Einfahren von Geraeten, die ueblicherweise am Kabel oder Draht eingesetzt werden, in Horizontalbohrungen. Im Folgenden werden das technische Konzept, ein Vergleich mit alternativen Verfahren, und verschiedene Referenzen des Well Tracotors {sup trademark} dargestellt. Weiterhin wird auf die Modifikationen eingegangen, die noetig waren, um dieses Geraet den Gegebenheiten in tiefen, heissen Gasbohrungen anzupassen. Abschliessend soll durch einen Ausblick auf zum Teil schon im Feldtest befindliche Weiterentwicklungen das weitere Potential dieser Technologie aufgezeichnet werden. (orig.)

  7. MR-imaging of finger osteoarthritis: Morphology and cartrilage signal intensity before and after treatment with ademetionin; Magnetresonanztomographie der Fingerpolyarthrose: Morphologie und Knorpelsignalverhalten unter Ademetonintherapie

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, H. [Radiologische Klinik, Abt. fuer Roentgendiagnostik und Nuklearmedizin, Univ.-Klinikum Steglitz, FU Berlin (Germany); Stahl, H. [Radiologische Klinik, Univ.-Klinikum Rudolf-Virchow, FU Berlin (Germany); Sieper, J. [Medizinische Klinik und Poliklinik, Univ.-Klinikum Steglitz, FU Berlin (Germany); Wolf, K.J. [Radiologische Klinik, Abt. fuer Roentgendiagnostik und Nuklearmedizin, Univ.-Klinikum Steglitz, FU Berlin (Germany)

    1995-01-01

    This report deals with a prospective study of 21 patients with finger osteoarthritis treated over a period of three months with either Ademetionin (therapy group: 14/21) or without (control group: 7/21). MR-Imaging was carried out before and after treatment using spin-echo and 3D-Flash sequences. Morphological parameters and signal intensity changes of the hyaline cartilage were evaluated. The increase of the cartilage signal intensity was significant in the therapy group, this can be interpreted as an structural improvement. Also a decrease of the cartilage signal intensity with age was found. The morphological parameters showed no significant changes in the therapy and control groups. (orig.) [Deutsch] Im Rahmen einer prospektiven Studie wurden magnetresonanztomographische Untersuchungen bei Patientinnen mit Fingerpolyarthrose vor und nach Ademetionintherapie durchgefuehrt. Es erfolgten zwei Messungen an einer Kontrollgruppe (n=7, keine Ademetionintherapie) und an der Therapiegruppe (n=14) im Abstand von drei Monaten. Zur Anwendung kamen eine Doppel-Spin-Echo-Sequenz sowie eine 3D-Flash-Sequenz. Ausgewertet wurden neben morphologischen Parametern auch der Signalintensitaetsverlauf im Bereich des hyalinen Gelenkknorpels der Interphalangealgelenke. Signifikant war der Knorpelsignalzuwachs unter Ademetionintherapie, dies kann als Zeichen einer strukturellen Befundbesserung interpretiert werden. Ebenfalls signifikant zeigte sich die Abnahme der Knorpelsignalintensitaet mit zunehmendem Lebensalter der Patientinnen. Bei den morphologischen Befundaenderungen konnte kein signifikanter Therapieeffekt festgestellt werden. (orig.)

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

    Directory of Open Access Journals (Sweden)

    Giovanni Mosti

    2017-09-01

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

  9. Gerichtete Erstarrung von Al-Si und Al-Si-Mn Legierungen unter dem Einfluss von magnetischen Wechselfeldern

    OpenAIRE

    Orth, Andreas

    2013-01-01

    In this work, samples of two alloys, Al-Si7 and Al-Si7-Mn1, are directionally solidified and their structure microscopically analysed. Thereby, the combined influence of induced current flow and intermetallic precipitates is of particular interest. A newly modified "Artemis" setup at the institute of material physics at the DLR in Cologne allows controlled solidification velocities of 30 to 240 micron/s under a constant temperature gradient of 3 K/mm. In using silica aerogels as part of the c...

  10. Deformation behavior and load limits of asphaltic concrete under the conditions of cores in embankment dams; Deformationsverhalten und Belastungsgrenzen des Asphaltbetons unter den Bedingungen von Staudammkerndichtungen

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, U.

    1998-12-31

    Based on the analysis of existing dams with asphaltic diaphragm and investigations in the three-phase-system of asphaltic concrete a recipe for the composition of asphaltic cores is recommended. For the construction, rest and operating period of an embankment dam the load and the reaction of the asphaltic concrete cores as well as the appearing stress and deformations are described. Extensive material testings have been performed and at 41 asphaltic concrete specimens triaxial stress controlled pressure and creeping tests have been carried out. The evaluation of the triaxial tests led to proportions of the main stress and deformation limits as criteria of breaking. Under application of the standard equation for nonlinear viscoelastic element-laws a rheonom element formulation was developed from the experiment data and transformed into its differential form. With this approach the stress and deformation behavior of watertight asphaltic diaphragm can be precalculated for a period up to 10 years. The applicability of this approach, which can be also used within FE-calculations as well, is illustrated in four examples. (orig.) [Deutsch] Nach der Analyse bestehender Staudaemme mit Asphaltbetonkerndichtung und Untersuchungen zum Dreiphasensystem Asphaltbeton wird eine Rezepturempfehlung fuer den Asphaltkerndichtungsbau aufgestellt. Fuer die Bau-, Ruhe- und Betriebsphase eines Staudammes werden die Beanspruchungen und Reaktionen der Asphaltbetonkerndichtung sowie die auftretenden Spannungen und Verformungen beschrieben. Nach umfangreichen Materialpruefungen sind an 41 Asphaltbetonpruefkoerpern triaxiale spannungsgesteuerte Druck-Kriechversuche durchgefuehrt worden. Die Auswertung der Triaxialversuche ergab ein Grenzhauptspannungsverhaeltnis und Deformationsgrenzen als Bruchkriterien. Unter Verwendung der Standarformulierung fuer nichtlineare viskoelastische Stoffgesetze wurde aus den Versuchsdaten ein rheonomer Stoffansatz entwickelt und in seine differentielle Form

  11. Investigations of the surface tension of coal ash slags under gasification conditions; Untersuchungen zur Oberflaechenspannung von Kohleschlacken unter Vergasungsbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Melchior, Tobias

    2011-10-26

    In the context of CO{sub 2}-emission-induced global warming, greenhouse gases resulting from the production of electricity in coal-fired power plants gain increasing attention. One possible way to reduce such emissions is to gasify coal instead of burning it. The corresponding process is referred to as Integrated Gasification Combined Cycle and allows for the separation of CO{sub 2} before converting a synthesis gas into electrical energy. However, further improvements in efficiency and availability of this plant technology are needed to render the alternative generation of electricity sensible from an economic point of view. One corresponding approach introduces hot gas cleaning facilities to the gasification plant which guarantee a removal of slag particles from the synthesis gas at high temperatures. The development of such filters depends on the availability of data on the material properties of the coal ash slags to be withdrawn. In this respect, the surface tension is a relevant characteristic. Currently, the surface tension of real coal ash slags as well as of synthetic model systems was measured successfully by means of the sessile drop and the maximum bubble pressure method. With regard to the sessile drop technique, those experiments were conducted in a gasification-like atmosphere at temperatures of up to 1500 C. Furthermore, the pressure inside the experimental vessel was raised to 10 bar in order to allow for deriving the influence of this variable on the surface tension. In contrast, maximum bubble pressure trials were realised at atmospheric pressure while the gas atmosphere assured inert conditions. For performing sessile drop measurements, a corresponding apparatus was set up and is described in detail in this thesis. Three computer algorithms were employed to calculate surface tensions out of the photos of sessile drops and their individual performance was evaluated. A very good agreement between two of the codes was found while the third one

  12. Municipal climate protection as a measure for sustainable energy supply under the conditions of globalization and liberalization? An empirical investigation considering the municipal actors and public utility companies; Kommunaler Klimaschutz als Instrument einer nachhaltigen Energieversorgung unter den Bedingungen von Globalisierung und Liberalisierung? Eine empirische Untersuchung unter besonderer Beruecksichtigung der Akteure Kommune und Stadtwerke

    Energy Technology Data Exchange (ETDEWEB)

    Bielitza-Mimjaehner, Ralf

    2007-03-01

    With the background of the threatening global warming that requires a reduction of greenhouse gas emission by 20 % until 2010 und by 80% until 2050 in Germany, t is reasonable to consider local or municipal climate protection activities. A climate protection politics ''from the bottom'' is not only contributing to a real greenhouse gas reduction, but also triggering the stagnant international climate politics and enhances the sustainable development on a local level. Due to this fact amongst others the Enquete commission of the German Bundestag ''sustainable energy supply under the conditions of globalization and liberalization'' identifies the municipal climate protection activities as important part within the mix of measures that will allow the initiation of an alteration of the actual energy system toward a sustainable energy supply in the long-run. The consequences of globalization and liberalization on the municipal level have not yet been discussed or considered by the Enquete commission. This thesis analyses the conditions induced by the globalization and liberalization on the municipal climate protection activities as constituent of a sustainable energy supply. The project is focusing on the municipal actors and the public utility companies as central point of the considerations. [German] Vor dem Hintergrund einer drohenden globalen Erwaermung, die eine Reduktion der klimawirksamen Treibhausgase bundesweit um 20 % bis 2010 und um 80 % bis 2050 noetig macht, sind Klimaschutzaktivitaeten auf einer lokalen oder kommunalen Ebene in mehreren Dimensionen sinnvoll. Den tatsaechlichen, bezifferbaren Reduktionen von CO2, die hier geleistet werden, gesellt sich ein ''vorbildhafter'' Druck auf eine stockende internationale Klimapolitik hinzu, ebenso leistet die ''Klimaschutzpolitik von unten'' einer nachhaltigen Entwicklung der lokalen Ebene durch Lerneffekte Vorschub. Unter anderem aus

  13. Solar reactors for freshwater treatment in developing countries with high radiation intensity, with particular regard to part-project No. 1: Microbiology, process conception. Final report; Solarreaktoren fuer die Trinkwasseraufbereitung in Entwicklungslaendern mit hoher Sonnenstrahlungsintensitaet unter besonderer Beruecksichtigung von Teilprojekt 1: Mikrobiologie, Verfahrenskonzeption. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Watzke, E.; Roth, M.; Hoffmeier, C.

    2000-07-01

    Erhoehung der Bakterienabtoetungsraten wird die erhoehte Temperatur des behandelten Wassers in einem isolierten Sammelbehaelter ueber mehrere Stunden gehalten. Ausserdem wurden Trinkwasserentkeimungsgefaesse (TWEG) aus hoch UV-durchlaessigem Glas entwickelt, die ebenfalls zur Trinkwasserdesinfektion verwendet werden koennen. In einem Folgeprojekt werden mit den TWEA Langzeittests unter praxisrelevanten Anwendungsbedingungen in Entwicklungslaendern durchgefuehrt. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Eisenacher, Germar

    2014-01-28

    Spruce wood is frequently used as an energy absorbing material in impact limiters of packages for the transportation of radioactive material. A 9m drop test onto an unyielding target is mandatory for the packages. The impact results in a dynamic compression load of the spruce wood inside the impact limiter. The lateral dilation of the wood is restrained thereby due to encasing steel sheets. This work's objective was to provide a material model for spruce wood based on experimental investigations to enable the calculation of such loading conditions. About 600 crush tests with cubical spruce wood specimens were performed to characterize the material. The compression was up to 70% and the material was assumed to be transversely isotropic. Particularly the lateral constraint showed to have an important effect: the material develops a high lateral dilation without lateral constraint. The force-displacement characteristics show a comparably low force level and no or only slight hardening. Distinctive softening occurs after the linear-elastic region when loaded parallel to the fiber. On the other hand, using a lateral constraint results in significantly higher general force levels, distinctive hardening and lateral forces. The softening effect when loaded parallel to the fiber is less distinctive. Strain rate and temperature raise or lower the strength level, which was quantified for the applicable ranges of impact limiters. The hypothesis of an uncoupled evolution of the yield surface was proposed based on the experimental findings. It postulates an independent strength evolution with deviatoric and volumetric deformation. The hypothesis could be established using the first modeling approach, the modified LS-DYNA material model MAT075. A transversely isotropic material model was developed based thereupon and implemented in LS-DYNA. The material characteristics of spruce wood were considered using a multi-surface yield criterion and a non-associated flow rule. The

  15. New approaches for the reliability-oriented structural optimization considering time-variant aspects; Neue Ansaetze fuer die zuverlaessigkeitsorientierte Strukturoptimierung unter Beachtung zeitvarianter Aspekte

    Energy Technology Data Exchange (ETDEWEB)

    Kuschel, N.

    2000-07-01

    The optimization of structures with respect to cost, weight or performance is a well-known application of the nonlinear optimization. However reliability-based structural optimization has been subject of only very few studies. The approaches suggested up to now have been unsatisfactory regarding general possibility of application or easy handling by user. The objective of this thesis is the development of general approaches to solve both optimization problems, the minimization of cost with respect to constraint reliabilty and the maximization of reliability under cost constraint. The extented approach of an one-level-method will be introduced in detail for the time-invariant problems. Here, the reliability of the sturcture will be analysed in the framework of the First-Order-Reliability-Method (FORM). The use of time-variant reliability analysis is necessary for a realistic modelling of many practical problems. Therefore several generalizations of the new approaches will be derived for the time-variant reliability-based structural optimization. Some important properties of the optimization problems are proved. In addition some interesting extensions of the one-level-method, for example the cost optimization of structural series systems and the cost optimization in the frame of the Second-Order-Reliabiity-Method (SORM), are presented in the thesis. (orig.) [German] Die Optimierung von Tragwerken im Hinblick auf die Kosten, das Gewicht oder die Gestalt ist eine sehr bekannte Anwendung der nichtlinearen Optimierung. Die zuverlaessigkeitsorientierte Strukturoptimierung wurde dagegen weit seltener untersucht. Die bisher vorgeschlagenen Ansaetze koennen bezueglich ihrer allgemeinen Verwendbarkeit oder ihrer nutzerfreundlichen Handhabung nicht befriedigen. Das Ziel der vorliegenden Arbeit ist nun die Entwicklung allgemeiner Ansaetze zur Loesung der beiden Optimierungsprobleme, einer Kostenminimierung unter Zuverlaessigkeitsrestriktionen und einer

  16. Numerically efficient simulation of multi-vaporator air conditioners in highly dynamic boundary conditions; Numerisch effiziente Simulation von Mehrverdampfer-Klimaanlagen unter hochdynamischen Randbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, Christian; Kaiser, Christian [TLK-Thermo GmbH, Braunschweig (Germany); Tegethoff, Wilhelm; Koehler, Juergen [TU Braunschweig (Germany). Inst. fuer Thermodynamik

    2011-07-01

    In the development of physically based models for dynamic simulations of cycle processes, a good equilibrium must be chosen between the degree of detailing and the speed of calculation. Dynamic modelling of mult-evaporator air conditioners is a special challenge as the interaction of several heat transfer fluides at one pressure level may result in numerically challenging effects like reflux. The contribution goes into the simulation of the heat transfer fluids in such systems in highly dynamic boundary conditions, e.g. after shutoff of the compressor. There are different modelling methods, e.g. finite volume, moving boundary, or finite element analysis. The methods are presented and evaluated. For the 1-D finite volume method, various established simplification strategies are presented that may enhance numerical efficiency. It is also shown that the equation system will not always be solvable with these strategies, and an approach to ensure solvability is presented. The new approach is illustrated by the example of a multi-evaporator bus air conditioner. [German] Bei der Erstellung von physikalisch basierten Modellen fuer die dynamische Simulation von Kreisprozessen muss ein gutes Gleichgewicht zwischen Detaillierungsgrad und Rechengeschwindigkeit gewaehlt werden: Das Modell muss die Realitaet hinreichend genau abbilden, im Gegenzug jedoch auch innerhalb eines angemessenen Zeitraums Ergebnisse liefern sowie in allen Betriebszustaenden loesbar sein. Die dynamische Modellierung von Mehrverdampfer-Klimaanlagen stellt im Vergleich zu einfachen Kreisprozessen eine besondere Herausforderung dar, da in diesen Systemen die Interaktion mehrerer Waermeuebertrager auf einem Druckniveau zu numerisch herausfordernden Effekten wie z. B. Rueckstroemung fuehren kann. Dieser Beitrag beschaeftigt sich mit der Simulation der Waermeuebertrager in diesen Systemen unter hochdynamischen Randbedingungen wie z. B. einer Abschaltung des Verdichters. Zur Modellierung der Waermeuebertrager

  17. Investigations on radionuclide release and on the corrosion behaviour of spent fuels from research reactors under disposal conditions. Final report; Untersuchungen zur Radionuklidfreisetzung und zum Korrosionsverhalten von bestrahltem Kernbrennstoff aus Forschungsreaktoren unter Endlagerbeedingungen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Bruecher, H.; Curtius, H.; Fachinger, J.; Kaiser, G.; Mazeina, L.; Nau, K.

    2003-12-01

    From the present report 'Untersuchungen zur Radionuklidfreisetzung und zum Korrosionsverhalten von bestrahltem Kernbrennstoff aus Forschungsreaktoren unter Endlagerbedingungen' with the code number FKZ 9108 carried out in the time periode 01.06.1998 till 30.11.2001 the following results can be withdrawn: U/Al-RR-fuel elements corroded slowly in granite water (Grimsel-West) at 90 C under anaerobic conditions. For a complete dissolution of the fuel element a time period of 10{sup 3} years is assumed according to present conservative results. In salt brines, especially in magnesium chloride rich brines the corrosion rate is high. Addition of GGG40 (basic material of the fuel element container with iron as main element) had an acceleration effect. A complete dissolution of the fuel is achieved within a couple of months. Under aerobic and under anaerobic conditions the bulk of released radionuclides were fixed by the corrosion products formed (secondary phases). The actinides were mobilised by variation of the ionic strength of the leaching solution. This process can be explained by phase conversion reactions within the secondary phases. Secondary phases formed by corrosion of a non-irradiated U/Al-RR-fuel element, were analysed and hydrotalcites were identified as phase components. This result justifies the assumption, that hydrotalcites are components of the corrosion products from irradiated fuels. To clarify the questions which bindings exist between radionuclides and secondary phases, sorption experiments were performed. The sorption experiments were performed in salt brines and in granite water using repository relevant radionuclides and minerals which are considered to represent thermodynamic final components of the secondary phases. Pu sorbed as cationic species quantitatively and the binding is covalent. In granite water the same behaviour was found for Am. (orig.) [German] Aus dem vorliegenden Bericht 'Untersuchungen zur Radionuklidfreisetzung

  18. Assimilation of carbon and transport of assimilates in coniferous trees under the influence of airborne pollutants. Photosynthesis rate and assimilate distribution in young fir trees (Picea abies [L.]Karst.) under controlled exposure to ozone. Final report; Assimilation von Kohlenstoff und der Assimilattransport in Coniferen unter dem Einfluss von Luftschadstoffen. Photosyntheseleistung und Assimilatverteilung in jungen Fichten (Picea abies [L.]Karst.) unter kontrollierter Ozon-Exposition. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Willenbrink, J.; Schatten, T.

    1992-12-31

    In this project, effects of long-term, low-level ozone exposure on CO{sub 2}fixation and assimilate partitioning in 4-years spruces old were studied. 1. In October, ozone exposure resulted in a 40% decrease of photosynthesis. Chlorophyll content was not altered. Depression of net photosynthesis by ozone exposure fluctuates. At least partly, this depression of net photosynthesis might reflect an increase of respiration. After 6 weeks of ozone exposure, both stomatal conductivity and transpiration seemed to be lowered. However, internal [CO{sub 2}] and water use efficiency were not significantly altered. 2. Compared with the control, needles of ozone-exposed plants exhibited a shift of the {sup 14}C-ratio of {beta}-carotene/xanthophylls which effect faded away with the season (October). 3. In August and October, translocation of {sup 14}C-assimilates from the {sup 14}C-fed source leaves seems to be impeded by ozone exposure. 4. No O{sub 3}-related differences were found for the lipophilic as well as for the fractions of organic or amino acids. For the sink tissues (twig, stem, root), less label was found in non-starch residue in August (main growth season), in O{sub 3}-exposed plants. 5. Starch and sugar content of cortex, cambium, xylem, and of the root follow annual cycles. Under ozon exposure, levels of {sup 14}C-starch and {sup 14}C-sucrose are lowered whereas in the needles, build-up of {sup 14}C-starch was detected. 6. Obviously, long-term low-level ozone affects allocation of assimilates. Secondary effects on chloroplasts by the treatment cannot be excluded. (orig./UWA) [Deutsch] Unter Labor- bzw. Gewaechshausbedingungen wurde der Einfluss einer kontrollierten Ozonexposition auf die Photosyntheseleistung und die Assimilatverteilung in 4-jaehrigen Fichten untersucht. 1. Unter Ozon-Exposition wird die Netto-Photosyntheserate in den jungen Nadeln zum Herbst hin reduziert, waehrend der Chlorophyllgehalt unbeeinflusst bleibt. Die Photosyntheserate der jungen Nadeln

  19. Radiology in managed care environment: Opportunities for cost savings in an HMO; Radiologie unter Managed-Care-Bedingungen. Einsparpotenziale aus der Sicht einer Krankenversicherung in den USA

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, C. [Universitaet Kiel (Germany). Klinik fuer Allgemeine Chirurgie und Thoraxchirurgie; Mohr, A. [University of California, San Francisco (United States). Dept. of Radiology; Universitaet Kiel (Germany). Klinik fuer Radiologische Diagnostik; Moeller, J. [Universitaet Bielefeld (Germany). Fakultaet fuer Gesundheitswissenschaften; Levin-Scherz, J. [Tufts Healthplan, Boston (United States); Heller, M. [Universitaet Kiel (Germany). Klinik fuer Radiologische Diagnostik

    2003-09-01

    : Darstellung des Einsparungspotenzials, welches einer effizienten Nutzung von Radiologieleistungen in einer Health-Maintenance-Organisation (HMO) innewohnt, und der zur Realisierung verwendeten Managed-Care-Techniken. Material und Methoden: Im Rahmen eines Projektes zur Kostenreduktion an einer HMO in den USA wurden die Ursachen fuer gestiegene Ausgaben im Bereich Radiologie (''Radiology-Utilisation-Line'') untersucht. Durch umfassende Datenanalysen, Ueberpruefungen der Kodierlogik, Interviews mit Angestellten sowie kritische Beleuchtung der Vertragsbeziehungen zu Leistungserbringern konnte das Einsparpotenzial beziffert werden. Saemtliche Daten wurden in Microsoft Excel {sup trademark} dokumentiert und unter Verwendung von SPSS 8.0 (Statistical Package for the Social Sciences) fuer Windows {sup trademark} mithilfe nicht-parametrischer Tests ausgewertet. Ergebnisse: Hauptursache war eine verstaerkte Verordnung von Radiologieleistungen pro versichertem Patienten, wobei die Kosten pro Untersuchung annaehernd gleich blieben. Ein wesentlicher Kostenhebel lag in der Verbesserung des elektronischen Abrechnungssystems, welches fuer eine Ueberbezahlung von Leistungen verantwortlich war. Die Gestaltung der vertraglichen Risikovereinbarungen zwischen Versicherer und Leistungserbringer sowie die Qualitaet der Managementstrukturen innerhalb der radiologischen Einrichtungen hatten einen signifikanten Einfluss auf deren Wirtschaftlichkeit. Ferner konnte nachgewiesen werden, dass Aerzte mit eigenen Roentgenanlagen bis zu 4-5-mal mehr Untersuchungen veranlassen als Aerzte ohne eigene Roentgenausstattung und so einen erheblichen Kostentreiber darstellen. (orig.)

  20. Receptor imaging of schizophrenic patients under treatment with typical and atypical neuroleptics; Nuklearmedizinische Rezeptordiagnostik bei schizophrenen Patienten unter Therapie mit typischen und atypischen Neuroleptika

    Energy Technology Data Exchange (ETDEWEB)

    Dresel, S.; Tatsch, K. [Klinik und Poliklinik fuer Nuklearmedizin der Ludwig-Maximilians-Univ. Muenchen (Germany); Meisenzahl, E. [Psychiatrische Klinik der Ludwig-Maximilians-Univ. Muenchen (Germany); Scherer, J. [Bezirkskrankenhaus Haar (Germany)

    2002-09-01

    -motorische Nebenwirkungen hervorzurufen. Die Besetzung postsynaptischer Dopamin-D2-Rezeptoren wird als ein wesentlicher Aspekt der antipsychotischen Wirksamkeit der Neuroleptika angesehen. Diese koennen nuklearmedizinisch durch [I-123]IBZM-SPECT dargestellt werden. Fuer das typische Neuroleptikum Haloperidol wurde eine dosisabhaengige, exponentielle Besetzung der Dopamin-D2-Rezeptoren nachgewiesen. Ab einem Schwellenwert des spezifischen Bindungsindex von 0,4 (Norm: >0,95) zeigten mit einer Ausnahme alle untersuchten Patienten extrapyramidal-motorische Nebenwirkungen. Auch unter Therapie mit dem atypischen Neuroleptikum Clozapin ergab sich eine exponentielle Dosis-Wirkungsbeziehung mit jedoch einem deutlich flacheren Kurvenverlauf im Vergleich zu Haloperidol. Extrapyramidalmotorische Nebenwirkungen traten bei diesen Patienten nicht auf. Neuere, als atypisch eingestufte Neuroleptika wie Risperidon und Olanzapin zeigten ebenfalls eine exponenzielle Dosis-Wirkungsbeziehung, wobei deren Kurvenverlaeufe zwischen denen von Haloperidol und Clozapin lagen. Extrapyramidal-motorische Nebenwirkungen traten bei den letzteren Neuroleptika seltener als bei Haloperidol, bei Olanzapin nur bei einem Patienten in unserem eigenen Patientengut auf. Das pharmakologische Profil atypischer Neuroleptika zeichnet sich neben der Bindung an die postsynaptischen Dopamin-D2-Rezeptoren auch durch Bindung an Rezeptoren diverser anderer Neurotransmittersysteme, insbesondere des serotonergen Systems, aus. Somit ist wahrscheinlich, dass die niedrigere Inzidenz fuer extrapyramidal-motorische Nebenwirkungen bei atypischen Neuroleptika durch (orig.)

  1. Percolation experiments to determine fluid-matrix interaction (with particular regard to pretreatment of the drill core); Kerndurchstroemungsversuche zur Ermittlung von Fluid-Matrix-Wechselwirkungen (unter besonderer Beruecksichtigung der Kernvorbehandlung)

    Energy Technology Data Exchange (ETDEWEB)

    Martin, M; Seibt, A [TU Bergakademie Freiberg (Germany). Inst. fuer Bohrtechnik und Fluidbergbau; Hoth, P [GeoForschungsZentrum Potsdam (Germany)

    1997-12-01

    The injection of fluids into sandstone reservoirs leads to interactions between these waters, the reservoir rocks, and the formation fluids. Estimations about possible permeability reducing processes caused by these interactions are therefore of great importance for the exploitation of sandstone aquifers as geothermal reservoirs. Percolation experiments under in situ conditions with core samples from North German geothermal boreholes were done in order to investigate these fluid-rock interactions. (orig./AKF) [Deutsch] Die Injektion von Fluiden in Aquiferspeicher fuehrt zu Wechselwirkungen zwischen dem Speichergestein, den Formationsfluiden und den injizierten Loesungen. Fuer die Bewirtschaftung der Speicher sind insbesondere Kenntnisse ueber moegliche Permeabilitaetsreduzierungen durch diese Wechselwirkungen von Bedeutung. Mit Hilfe von Kern-Durchstroemungsexperimenten, durchgefuehrt unter lagerstaettenaehnlichen Bedingungen mit Original- bzw. modifizierten Fluiden, wurde daher das Durchstroemungsverhalten von unterschiedlich ausgebildeten Reservoirsandsteinen aus norddeutschen Geothermiebohrungen untersucht. (orig./AKF)

  2. MR-imaging of the breast at 0.5 Tesla: menstrual-cycle dependency of parenchymal contrast enhancement in healthy volunteers with oral contraceptive use?; MR-Mammographie bei 0,5 Tesla: Menstruationszyklusabhaengigkeit der Kontrastmittelanreicherung unter hormoneller Kontrazeption?

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzen, J.; Welger, J.; Krupski, G.; Adam, G. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Hamburg-Eppendorf (Germany); Lisboa, B.W. [Klinik und Poliklinik fuer Frauenheilkunde und Geburtshilfe, Universitaetsklinikum Hamburg-Eppendorf (Germany)

    2003-04-01

    Introduction: To evaluate changes of contrast medium enhancement of the breast parenchyma due to menstrual cycle in healthy volunteers with oral contraceptive use in MR-imaging of the breast. Material and Methods: 15 healthy volunteers (age: 22 - 36, mean 28,2) without breast disease were examined two times during one menstrual cycle (days 7 - 14 and days 21 - 2). Two volunteers were examined only in the second part of the cycle (days 21 - 2). All volunteers used oral contraceptives for more than 6 month continuously. Examinations were performed with a 0,5 T magnet (dynamic 3D-gradient echo protocol with subtraction postprocessing). We evaluated the number of enhancing foci and the parenchymal contrast medium enhancement during the different phases of the cycle by region of interest. Results: Only a total of two enhancing foci were found in 2 of 17 volunteers. Time/signal intensity diagrams in these both cases were not suspicious (< 80% initial signal increase after of contrast medium injection, no wash-out phenomenon) and sonography of the breast in these two cases was inconspicuous. Contrast medium enhancement of breast parenchyma in cycle days 7 - 14 (mean enhancement: 0.12 - 0.26, minutes 1 - 9 p.i.) was not significantly different (p = 0.2209; Wilcoxon signed rank test) from cycle days 21 - 2 (mean: 0.13 - 0.32). Conclusion: Menstrual cycle dependency of parenchymal contrast medium enhancement seems to be of minor relevance for premenopausal women with use of oral contraceptives. (orig.) [German] Fragestellung: Untersuchung der Kontrastmittelaufnahme des Brustparenchyms in Abhaengigkeit vom Menstruationszyklus bei gesunden Probandinnen unter oraler Kontrazeption. Material und Methode: Bei 15 gesunden Probandinnen ohne Brusterkrankung in der Anamnese wurde eine MR-Mammographie zweimal waehrend eines Menstruationszyklus durchgefuehrt (Zyklustag: 7 - 14 und 21 - 2). Bei zwei weiteren Probandinnen erfolgte die MR-Mammographie nur in der zweiten Zyklushaelfte

  3. The value of magnetic resonance imaging (MRI) in the treatment planning of vertebral metastasis considering economic aspects. A cost benefit-analysis; Die Wertigkeit der Magnetresonanztomographie (MRT) unter oekonomischen Aspekten bei der Bestrahlungsplanung von Wirbelkoerpermetastasen. Eine Kosten-Nutzen-Analyse

    Energy Technology Data Exchange (ETDEWEB)

    Prott, F.J.; Schlehuber, E.; Scharding, B.J.; Rinast, E. [Strahlentherapie Wiesbaden, St.-Josefs-Hospital (Germany); Micke, O. [Klinik und Poliklinik fuer Strahlentherapie - Radioonkologie, Universitaetsklinikum Muenster (Germany)

    2002-05-01

    Is magnetic resonance imaging (MRI) based target volume definition for treatment planning of vertebral metastasis effective under economic considerations.From 1994 to 1999, a total of 137 patients with bone metastases affecting the vertebral column underwent MRI of the cercival, thoracic, or lumbar spine for the treatment planning of palliative radiation therapy. The following radiation treatment consisted in a irradiation of the affected vertebral region up to a total dose of 30-40 Gy.The cost calculation for radiotherapy and magnetic resonance tomography was done using the common tariff model (EBM) of the German Health Insurances.In 73% of patients (101 patients), magnetic resonance imaging resulted in marked corrections of the irradiation fields which would have resulted in the necessity of treatment for recurrence in the case of treatment planning without MRI.Consequently, the higher cost of MRI of 345.00 DEM (176,40 EUR) lead to a saving of 497.00 DEM (254,11 EUR) compared to a recurrence treatment of 10 fractions and of 1,428.00 DEM (730,12 EUR) compared to 20 fractions. The transport expenses for the second treatment could be saved as well.Even under economic considerations MRI is effective. (orig.) [German] Ist eine MRT-gestuetzte Zielvolumendefinition bei der Strahlentherapie von Knochenmetastasen ein sinnvolles Vorgehen unter oekonomischen Gesichtspunkten?1994-1999 wurde bei 137 Patienten mit einem ossaer metastasierenden Tumor und Befall der Wirbelsaeule eine Magnetresonanztomographie (MRT) zur Planung einer palliativen Radiatio durchgefuehrt. Die nachfolgende Strahlentherapie bestand aus einer Radiatio des betroffenen Wirbelkoerperabschnitts bis zu einer Gesamtherddosis von 30-40 Gy. Fuer die Berechnung der Kosten wurde der einheitliche Bewertungsmassstab der Deutschen Krankenkassen zugrunde gelegt.Aufgrund der MRT-Untersuchungen wurde bei 73% der Patienten eine Veraenderung des Bestrahlungsfeldes vorgenommen, die im Falle einer nicht MRT

  4. Powertrain definitions for Opel's brand sound considering the vehicle portfolio; Gestaltung des Powertrains fuer den Opel-Brand-Sound unter Beruecksichtigung der unterschiedlichen Positionierung der Fahrzeugpalette

    Energy Technology Data Exchange (ETDEWEB)

    Bernhard, U.; Herrmann, G.; Schmidt, G.O. [Adam Opel AG, Ruesselsheim (Germany)

    2002-07-01

    The change of value orientation in Western Europe lead to an increase of emotions buying a car. In addition to classic factors like design, today the carmakers use elements of emotion like brand sound to inspire the customers. On the one hand the job of the acoustic engineers is to meet the acoustic expectations depending on driving conditions. On the other hand there are to develop both combining elements over the whole portfolio and elements which allow a defined position of a carline-powertrain combination in the market. (orig.) [German] Im Zuge der Wandlung der westlichen Gesellschaften spielen Emotionen beim Kauf eines Automobils eine immer staerkere Rolle. Zur Unterstuetzung klassischer Mittel wie dem Design werden heute weitere emotionalisierende Elemente zur Begeisterung der Kunden eingesetzt, unter anderem auch das Klangbild eines Fahrzeugs. Dabei liegt die Aufgabe einerseits darin, der unterschiedlichen Erwartungshaltung in Abhaengigkeit vom Fahrzustand des Fahrzeugs gerecht zu werden. Andererseits die Gestaltung des Klangbildes so durchzufuehren, dass innerhalb des Portfolios sowohl verbindende Elemente als markentypisch zu finden sind als auch der Marktpositionierung gerecht werdende Elemente der einzelnen Fahrzeugtypen zu generieren. (orig.)

  5. Comparison calculation/experiment on the load case ``shutdown of TH high pressure pumps under consideration of fluid structure interaction``; Vergleich Rechnung/Messung zum Lastfall ``Abschaltung der TH-Hochdruckpumpen unter Beruecksichtigung der Fluid-Struktur-Wechselwirkung``

    Energy Technology Data Exchange (ETDEWEB)

    Erath, W.; Nowotny, B.; Maetz, J. [KED, Rodenbach (Germany)

    1998-11-01

    Measurements of an experiment in a pipe system with pump shutdown and valve closing have been performed in the nuclear power plant KRB II. Comparative calculations of fluid and structure including interaction show an excellent agreement with the measured results. Theory and implementation of the fluid/structure interaction and the results of the comparison are described. It turns out that the consideration of the fluid/structure interaction is mostly a significant increase of the effective structural damping. (orig.) [Deutsch] Es wurden Messungen am nuklearen Nachkuehlsystem des Kernkraftwerks Gundremmingen (KRB II) bei einem Versuche mit Pumpenabschalten und Ventilschliessen durchgefuehrt. Vergleichsrechnungen der Fluid-Strukturdynamik unter echter Beruecksichtigung der Wechselwirkung ergaben eine ausgezeichnete Uebereinstimmung der Rechnung mit den Messungen. Es werden Theorie und Implementierung der Koppelung der Fluid- und Struktur-Berechnungen sowie die Vergleiche von Messung und Rechnung beschrieben. Es ergibt sich, dass die Beruecksichtigung der Wechselwirkung notwendig ist zur genaueren Berechnung von `weichen` Rohrleitungsystemen. Eine wichtige Folge der Wechselwirkung ist meist eine deutliche Erhoehung der effektiven Strukturdaempfung. (orig.)

  6. Optimizing the gear efficiency under consideration of thermal optimisation strategies and customer-specific load conditions; Optimierung des Getriebewirkungsgrads unter Beruecksichtigung thermischer Optimierungsstrategien und kundenspezifischer Lastkollektive

    Energy Technology Data Exchange (ETDEWEB)

    Inderwisch, Kathrien; Kuecuekay, Ferit [Technische Univ. Braunschweig (Germany). Inst. fuer Fahrzeugtechnik

    2012-11-01

    Nowadays, the automotive industry have been received more attention to improve the transmission efficiency. Most of the researches have been concentrated on development and optimisation on transmission actuators, shifting elements, bearings, lubricants or lightweight constructions. Due to the low load requirements and associated low efficiencies for transmissions in driving cycles the transmissions cause energy losses which cannot be neglected. Two main stategies can be followed up for the optimisation of transmission efficiency. At first the efficiency benefit of transmissions through optimisation of hardware components will be presented. The second possibility is the representation of an optimal thermal management especially at low temperatures. Warming-up the transmission oil or transmission components can increase the efficiency of transmissions significantly. Techniques like this become more important in the course of electrification of drive trains and therefore decreased availability of heat. A simulation tool for calculation and minimisation of power loss for manual and dual-clutch transmissions was developed at the Institute of Automotive Engineering and verified by measurements. The simulation tool calculates the total transmission efficiency as well as the losses of individual transmission components depending on various environmental conditions. In this paper, the results in terms of increasing the efficiency of transmissions by optimisation of hardware components will be presented. Furthermore, the effects of temperature distribution in the transmission as well as the potential of minimising loss at low temperatures through thermal management will be illustrated. (orig.)

  7. Further development of landfill sealing systems. Subproject 20: long-term behaviour of earthen layers in landfill liners, moisture conditions under the action of temperature; Weiterentwicklung von Deponieabdichtungssystemen. Teilvorhaben 20: Langzeitverhalten von Erdstoffschichten in Deponiebasisabdichtungen, Feuchtehaushalt unter Temperatureinwirkung

    Energy Technology Data Exchange (ETDEWEB)

    Holzloehner, U.; Schossig, W.; Wuttke, W.; Ziegler, F.

    1996-12-31

    The sealing properties of the earthen layers in landfill liners depend on water content, which is not constant but changes according to the moisture conditions of the landfill and the adjacent soil. Earthen layers in landfill liners tend to lose water over the course of time and this may result in desiccation cracking. To study the behaviour of soils undergoing desiccation, test devices and methods were developed to evaluate the water transport characteristics of soil samples. Measurement of the temporal and spatial changes in moisture distribution within the cylindrical soil sample was accompanied by a calculation in which diffusion coefficients were iteratively varied so as to reach optimum agreement with the observed moisture distribution. Overburden pressure can to some extent prevent desiccation. Therefore test devices were developed which made it possible to load soil samples simultaneously by vertical stress and by suction. (orig./SR) [Deutsch] Die Dichtigkeit von Erdstoffschichten in Deponieabdichtungen haengt vom Wassergehalt ab, der nicht konstant ist, sondern sich entsprechend dem Feuchtehaushalt von Deponie und umgebendem Boden aendert. Die Erdstoffabdichtungssschichten tendieren langfristig zum Trocknerwerden, wodurch es zu Rissen kommen kann. Um das Austrocknungsverhalten zu untersuchen, wurden Versuchsgeraete und -verfahren zur Bestimmung von Wassertransportkennwerten an Bodenproben entwickelt. Die Messung der zeitlichen und oertlichen Aenderung der Feuchteverteilung in der zylindrischen Bodenprobe wurde durch eine Rechnung begleitet, in der die eingegebenen Diffusionskoeffizienten iterativ variiert wurden, bis optimale Uebereinstimmung mit der gemessenen Feuchteverteilung erreicht war. Auflast kann Austrocknung bis zu einem gewissen Grad verhindern. Deshalb wurden Geraete entwickelt, in denen Bodenproben gleichzeitig einer Wasserspannung und einer vertikalen Spannung ausgesetzt werden koennen. (orig./SR)

  8. Investigations to the reduction of the drying time of temperature sensitive goods with assistance of sorbents. Final report; Untersuchungen zur Verkuerzung der Trocknungszeit temperaturempfindlicher Gueter unter Verwendung von Sorptionsmitteln. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Coutelle, R.

    1998-07-31

    It was the aim of the project to improve the solar drying process with assistance of solar regenerated sorbents. Fruits, vegetables, herbs and mushrooms were dried in hurdles and calcium chloride solutions were concentrated in black plastic basins with solar energy during the day. At night or at bad meteorological conditions the hurdles with the drying goods were set into the basins and capped in order to continue the drying process. By this means a microbial decay was prohibited and the drying time was shortened roughly by half. (orig.) [Deutsch] Ziel des Vorhabens war es, den Prozess der solaren Trocknung mit Hilfe von solar regenerierten Sorptionsmitteln zu verbessern. Tagsueber wurden mit Solarenergie Fruechte, Gemuese, Kraeuter und Pilze in Horden getrocknet, und Calciumchloridloesungen wurden in schwarzen Kunststoffwannen regeneriert. Zur Fortsetzung der Trocknung waehrend der Nacht und bei unguenstigen Witterungsverhaeltnissen wurden die Horden mit den Trocknungsguetern in die Wannen gesetzt und abgedeckt. Durch dieses Verfahren konnte ein mikrobieller Verderb vermieden und die Trocknungszeit auf ca. die Haelfte verkuerzt werden. (orig.)

  9. Cross-sectoral modeling and optimization of a future German energy system, taking energy efficiency measures into account in the building sector; Sektoruebergreifende Modellierung und Optimierung eines zukuenftigen deutschen Energiesystems unter Beruecksichtigung von Energieeffizienzmassnahmen im Gebaeudesektor

    Energy Technology Data Exchange (ETDEWEB)

    Palzer, Andreas

    2016-07-01

    With the aim of reducing greenhouse gas emissions, comprehensive climate protection measures have already been adopted both nationally and internationally. This raises the question of how economically and ecologically useful system infrastructure looks, which at the same time ensures the supply reliability of all consumers. The regenerative energy model (REMod) presented in this book has been developed to provide answers. The sectors electricity, heat, transport and industry are considered for the first time simultaneous in an energy system model. In particular, in order to satisfy the criterion of reliability of supply, the model calculates the energy flows in hourly resolution for the period from today (2015) to 2050. The system is optimized with regard to minimum overall costs and under the boundary condition that a maximum set quantity of permitted greenhouse gas emissions is not exceed. On the example of Germany (REMod-D), the results show that, in particular, the interaction of the sectors can lead to strong differences in the design of the system infrastructure. [German] Mit dem Ziel den Ausstoss der Treibhausgase zu reduzieren, wurden bereits national wie international umfangreiche Klimaschutzmassnahmen verabschiedet. Hieraus ergibt sich die Frage wie eine oekonomisch und oekologisch sinnvolle Systeminfrastruktur aussieht, die gleichzeitig die Versorgungssicherheit aller Verbraucher gewaehrleistet. Das in diesem Buch vorgestellte Regenerative Energien Modell (REMod) wurde entwickelt um hierauf Antworten zu liefern. Beruecksichtigt werden erstmalig in einem Energiesystemmodell die Sektoren Strom, Waerme, Verkehr und Industrie gleichzeitig. Insbesondere um dem Kriterium der Versorgungssicherheit gerecht zu werden, berechnet das Modell die Energiefluesse in stuendlicher Aufloesung fuer den Zeitraum von heute (2015) bis 2050. Optimiert wird das System hinsichtlich minimaler Gesamtkosten und unter der Randbedingung, dass eine maximal vorgegebene Menge erlaubter

  10. Marginal flow in compressor cascades. Influence of gap, cascade geometry, loads and inflow boundary layer. Final report; Randstroemung in Verdichtergittern. Untersuchung der Randstroemung in Verdichtergittern unter dem Einfluss von Spalt, Gittergeometrie, Gitterbelastung und Zustroemgrenzschicht. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Huebner, J

    1996-07-01

    der Abstroemwinkelverteilung zusammengestellt und mit den Messungen verglichen. Dabei ergab sich eine grosse Streubreite der Korrelationen, die auf eine unterschiedliche Bewertung der Spaltweite und der aerodynamischen Belastung zurueckzufuehren ist. Die haeufig anzutreffende Trennung in einen reinen Spaltverlust und einen von der Spaltstroemung unbeeinflussten Sekundaerverlust erscheint physikalisch nicht sinnvoll. Unter Beruecksichtigung der experimentellen Ergebnisse wurden verbesserte Spaltverlust- und Abstroemwinkelkorrelationen erarbeitet. (orig.)

  11. Materials model for describing the austenite-martensite phase transformation considering transformation-induced plasticity; Ein Materialmodell zur Beschreibung der Austenit-Martensit Phasentransformation unter Beruecksichtigung der transformationsinduzierten Plastizitaet

    Energy Technology Data Exchange (ETDEWEB)

    Oberste-Brandenburg, C.

    1999-06-01

    In this thesis, a model to describe the austenite martensite transformation was developed. The transformation induced plasticity (TRIP) was taken into consideration. The model can be used to design complex structures. A local examination of the energy and entropy balance at the phase boundary serves as the starting point for the identification of the thermodynamical driving force and the thermodynamic flow. For both, a tensorial description is necessary for a general nonhydrostatically stressed solid. In the second part, a material law for the description of TRIP-Steels was developed based on the values derived in the first part. The different mechanical behavior of the phases, especially the differing yield stresses, was taken into account. The model developed was implemented into the finite element program MARC. Simulations of the material and the structural behavior were performed. The experimentally observed strong dependence of the transformation kinetics on the yield stress of the austenite and the dependence of the orientation of the martensite inclusion on the stress state could be verified. (orig.) [German] Im Rahmen dieser Arbeit wurde ein Materialmodell zur Beschreibung der Austenit-Martensit Phasenumwandlung unter Beruecksichtigung der transformationsinduzierten Plastizitaet (TRIP) entwickelt. Das Modell ist zur Berechnung ausgedehnter Strukturen einsetzbar. Eine lokale Betrachtung der Energie- und Entropiebilanz an der Phasengrenze bildet den Ausgangspunkt zur Identifikation der thermodynamischen Kraft und des thermodynamischen Flusses bei Beschreibung der Transformationskinetik. Fuer beide Groessen muss fuer den allgemein nichthydrostatischen Spannungszustand eine tensorielle Beschreibung verwendet werden. Im zweiten Teil der Arbeit bilden diese Groessen die Basis zur Entwicklung eines Stoffgesetzes zur Beschreibung des TRIP-Phaenomens. Es wird das unterschiedliche mechanische Verhalten der Phasen, insbesondere die stark unterschiedlichen

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-07-01

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

  13. Firing technology in practice - temperature, residence time, corrosion; Feuerungstechnik in der Praxis - Temperatur, Verweilzeit, Korrosion

    Energy Technology Data Exchange (ETDEWEB)

    Freimann, P.; Holl, D. [Muellheizkraftwerk Betriebsgesellschaft mbH, Burgkirchen/Alz (Germany)

    1998-09-01

    In a circular dated 1st Sept. 1994, i.e., after the issue of the pertinent planning decision, the Federal Environmental Ministry, BMU, laid down uniform standards on measurements and the parameterisation of the evaluation system for different operation states and loads. Subsequently, TUeV, the German Technical Control Board, prepared the parameterisation curves on the basis of these specifications. The implementation of the BMU paper of 1st Sept. 1994 did not result in any advantage, nor did it lead to a reduction of plant emissions, nor to advantages in the operation of the waste-fuelled cogeneration plant. On the contrary, elevated gas consumption and operating trouble due to frequent feed stops worsened the operating state of the plant. Elevated crude gas temperature in the boiler reduced the lifetime of the two boilers to a critical degree. An operating temperature of 850 C and a residence time of approx. 1 sec. in Burgkirchen waste-fuelled cogeneration plant have not worsened emission values while rendering the plant operable again. [Deutsch] Durch Rundschreiben d. BMU vom 01.09.1994 - also nach Erlass des Planfeststellungsbeschlusses - wurden einheitliche Vorgaben ueber Messungen und Parametrierung des Auswertesystems fuer die verschiedenen Betriebs- bzw. Lastzustaende erlassen. Unter Beruecksichtigung dieser Vorgaben wurden vom TUeV die Parametrierungskurven erstellt. Die Umsetzung des BMU-Papieres vom 01.09.1994 ergab keinerlei Vorteile, weder gab es eine Verringerung der anlagenbedingten Emissionen noch Vorteile fuer den Betrieb des MHKW`s. Im Gegenteil, erhoehte Gasverbraeuche und Betriebsstoerungen durch oftmalige Beschickungsstops verschlechterten den Betriebszustand. Erhoehte Rohgastemperatur im Kessel reduzierten die Lebensdauer der beiden Kessel kritisch. Der Betrieb mit 850 C und mit einer Verweilzeit von ca. 1 sec. fuehrt im MHKW Burgkirchen zu keiner Verschlechterung der Emissionswerte, macht aber die Anlagen wieder betreibbar. (orig./SR)

  14. Improved load flow control for distribution system operators under consideration of wind and solar performance prognosis; Verbesserte Lastflussfuehrung fuer Verteilnetzbetreiber unter Einbeziehung von Wind- und Solarleistungsprognosen

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Ralf [IDS GmbH, Ettlingen (Germany); Strunk, Achim [EWC Weather Consult GmbH, Karlsruhe (Germany)

    2012-07-01

    Smart grid and smart metering are the results from the social and legal intention to detach from the nuclear energy, to expand the production of renewable energy and to bring more competition into the energy market. The next decade will be characterized by extensive investments to integrate the myriad of distributed production plants into the network management, optimal use of the networks and the offer of flexible tariffs to end-users in order to respond to the effects of the weather-related production potential. With the predictability of depression measures distribution operators would be able to optimize the purchase from suppliers, the production in its own network and the feed-in performance of renewable energy systems and to derive the economic benefit from this. This requires a holistic approach to forecast which surpasses far beyond previous approaches for the optimization of the energy supply based on load profiles and forecasts of temperature and wind.

  15. Determination of W-erosion through optical spectroscopy under ITER-relevant plasma conditions; Bestimmung der Wolframerosion mittels optischer Spektroskopie unter ITER-relevanten Plasmabedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Laengner, Marko

    2016-11-21

    Tungsten (W) is used in present fusion experiments and is as well a material choice for future reactors like ITER and DEMO. However, tungsten eroded from the wall leads to high radiation losses in the plasma and the transport to the plasma center to critical plasma cooling. Therefore a detailed investigation of the interaction between eroded tungsten and the plasma is necessary. The emission of tungsten line radiation in the plasma and thus the shape of the emission profiles is characterized by excitation and ionisation. Quantitatively the ionisation can be described in terms of the ionisation rate coefficients. This knowledge is necessary for the interpretation of spectroscopic data and especially to determine tungsten fluxes into the plasma that are caused by tungsten erosion. Up to now, ionisation rate coefficients for neutral tungsten were not determined except for the plasma temperature range below 20 eV. For higher temperatures only uncertain calculated data or semi-empirical data is available. Therefore, within this thesis for the first time ionisation and emission processes of tungsten originating from tungsten erosion were investigated in the temperature range between (41±8) eV and (81±8) eV at the tokamak TEXTOR and ionisation rate coefficients were determined experimentally. Measured emission profiles of the W I(400.88 nm)-line show a typical exponential decrease that is caused by the ionisation of the neutral tungsten atoms. But moreover, at a distance of 1 to 2 mm away from the sputtered surface the emission initially increases to a maximum. By introducing a relaxation time between 0.5 and 1 μs before reaching the equilibrium of the population of the emitting energy level of this line the increase of the emission profiles can be reproduced. Simulating the emissions profiles through a Monte-Carlo-simulation that was developed in the scope of this thesis results in ionisation rate coefficients that are identical with values calculated through using

  16. Experimental determination and numerical simulation of viscositites in slag-systems under gasification conditions; Experimentelle Bestimmung und numerische Simulation von Viskositaeten in Schlackesystemen unter Vergasungsbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Nentwig, Thomas

    2011-07-01

    Silica melts are reflected in many different industrial and natural processes such as slags in steel production and gasification of coal, glass in the glass making industry, lava in the volcanology and in lots of other fields. Rheological properties like the viscosity of this silica melts are really important in all of these processes. A general and good working viscosity model would help all scientists and engineers, who have to simulate and optimise these processes. First, it is important to have the possibility to measure viscosities of slags. As part of this PhD thesis a new high-temperature high-pressure rotational viscosimeter is developed for measurements up to {>=}1600 C and 20 bar. Particularly in relation to the coal gasification process this two parameters are really important, because coal gasification occurs under high temperatures and high pressures. With this new viscosimeter it is possible to measure slag viscosities under realistic gasification conditions. To show that the new viscosimeter works quite good viscosity measurements of four real slags have been done. The influence of pressure and atmosphere on viscosity have been examined. The measurements are also compared with different viscosity models. The Arrhenius- and Weymann-Equation have been determined and the correlation between viscosity and basicity of the slag has been evaluated. In the second part of the Phd thesis a new viscosity model is developed. The model is based on the structure inside the slag and consists in existing thermodynamic models. After a detailed literature research the model is developed for the SiO{sub 2}-Al{sub 2}O{sub 3}-Na{sub 2}O-K{sub 2}O system. The quality of this new model is estimated by comparing calculated viscosity values with measurements found during the literature research. The new model is also compared with other existing models for viscosity calculation.

  17. Characterization of polyelectrolytes and lithium salts for electrochemical energy storage devices using novel measurement systems; Charakterisierung von Polyelektrolyten und Lithiumsalzen fuer elektrochemische Energiespeicher unter Verwendung neu entwickelter Messsysteme

    Energy Technology Data Exchange (ETDEWEB)

    Huber, Benedikt

    2013-04-08

    In the first part of this work, three imidazolium-based ionic liquid monomers with polymerizable vinyl groups and the resulting polyelectrolytes have been synthesized and characterized. Particular attention was paid to the purity of the materials. Besides comprehensive monomer and polymer analytics, electrical impedance spectroscopy was carried out to obtain information about the ion conducting properties of the three systems under investigation: poly(3-ethyl-1-vinylimidazolium)-bis(trifluoromethanesulfonyl)imide (P1), poly(3-methyl-1-(4-vinylbenzyl)imidazolium)-bis(trifluoromethanesulfonyl)imide (P2) and poly(1-butyl-3-methyl-2-(4-vinylphenethyl)imidazolium)-bis(trifluoromethanesulfonyl)imide (P3). The pure polymers, which are bis(trifluoromethanesulfonyl)imide (N(Tf)2) anion conductors, exhibit room-temperature conductivities of the order of 10-8 S/cm in the best case. The anion conduction mechanism is strongly influenced by the length of the spacer group between the polymer backbone and the imidazolium cations attached to the side chain. In polymers P1 and P2 with short spacer groups, intra- and inter-cation hopping of the N(Tf)2 anions can be distinguished below the glass transition temperature, while this is not possible in the case of polymer P3 with longer spacer groups. Furthermore, we have studied several mixtures of the best conducting polymer P2 with LiN(Tf)2, zwitterions and monomeric ionic liquid. While the zwitterions were capable of compensating for the conductivity drop due to Li salt addition, the addition of monomeric IL as plasticizer leads to a considerable conductivity enhancement without a significant loss of mechanical stability. In the second part of this work, three lithium salts, lithium bis(pentafluorophenyl)amide LiN(Pfp)2, lithium pentafluorophenyl-trifluoromethyl-sulfonylimide LiN(Pfp)(Tf) and lithium pentafluorophenyl-nonafluorobutyl-sulfonylimide LiN(Pfp)(Nf) were characterized with respect to their thermal and electrochemical

  18. Process measuring techniques applying in-line and on-line analyzers. Betriebsmesstechnik unter Einsatz von in-line und on-line Analysatoren

    Energy Technology Data Exchange (ETDEWEB)

    Oehme, F; Jola, M

    1982-01-01

    The measurement and control of classical physical parameters such as pressure, temperature etc, is frequently not sufficient now for optimum process control in chemistry and associated fields. Only the use of inline and online analysers makes it possible to maintain the narrow limits of chemical reaction conditions. This ABC pocket book should help the user to select the best from the large number of available methods of measurement. Using 120 alphabetically arranged key words with many cross-references, it has a well-thought-out treatment of basic measurements and descriptions of apparatus, and on the other hand, it contains selected typical examples of applications. Width rather than depth of information is aimed at. The electrochemical methods discussed are potentiometry (pH value, redox potential, direct potentiometry with ion selective electrodes), conductometry (measurement of conductivity) and voltammetry (polarography, ammetry). Photometry, the measurement of density, the refractive index, surface tension and viscosity are described. From the large number of applications, the examples of textile processing, the cellulose and paper industry, the surface treatment of materials and petrochemicals are discussed. Special attention is paid to the treatment of service water, drinking water and boiler feed water. In connection with questions of work and environmental protection, emission control and the treatment of domestic and industrial waste water are described. With 119 figs.

  19. Analysis of injection sprays by means of large high-speed engines under cold and evaporating conditions; Analyse von Einspritzsprays mittelschnelllaufender Grossmotoren unter kalten und verdampfenden Bedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Fink, Christian; Pinkert, Fabian; Harndorf, Horst [Rostock Univ. (Germany). Lehrstuhl fuer Kolbenmaschinen und Verbrennungsmotoren; Frobenius, Moritz [AVL Deutschland GmbH, Haimhausen (Germany)

    2011-07-01

    The introduction of future emission limits for marine diesel engines requires an improved understanding of the fuel injection process and mixture formation as well as the development of robust and powerful tools to calculate the emission generation. This publication presents research results of the project partners AVI Deutschland GmbH and Rostock University obtained in the associated project EMI-MINI II. Objective of the experimental part of the work is the fundamental investigation of the mixture formation at cold and evaporative conditions in a high-pressure and high-temperature chamber by means of optical methods. For the measurements, a modem, heavy fuel capable single circuit common-rail injector of a medium speed diesel engine is applied. Based on the experimental results a calibration and validation of spray break-up and evaporation models is done. The models are applied in a specific simulation approach in order to predict engine emissions. Characteristic feature of the chosen approach is the consideration of specific nozzle internal flow conditions as boundary conditions for the spray break-up models and thus for the ignition, combustion and emission generation. The presented results demonstrate that the applied models are very sufficient to calculate injection and mixture formation processes. By comparing calculated engine emissions to experimental results obtained by WTZ Rosslau gGmbH it is shown that the presented simulation approach is capable to predict the impact of varying engine parameters on NO{sub x}- and soot emissions effectively. (orig.)

  20. Pyrolysis of petroleum residues while making use of the hydrogen potential of polymer waste; Pyrolyse von Erdoelrueckstaenden unter Nutzung des Wasserstoffpotentials von Polymerabfaellen

    Energy Technology Data Exchange (ETDEWEB)

    Klemens, I; Butz, T; Rahimian, I; Linde, A [Institut fuer Erdoel- und Erdgasforschung, Clausthal-Zellerfeld (Germany)

    1998-09-01

    The hydrogen potential contained in waste plastics is to be utilized optimally for cracking of petroleum residues. Homogeneous distribution of the plastic particles in the petroleum residue is to ensure short distances between the hydrogen donor and acceptor, a sufficently large reaction surface, and stable mixing for further processing. Apart from homogeneity, another factor of interest is the influence of mixed-in polymer particles on the colloidal stability of the petroleum residue and the physico-chemical properties of the mixtures. With a view to further processing, the mixtures were analyzed for high-temperature stability, flow characteristics, and reaction behaviour during pyrolysis. (orig.) [Deutsch] Ziel dieses Vorhabens ist es, das in den Kunststoffabfaellen vorhandene Wasserstoffpotential optimal fuer eine tiefergehende Spaltung der Erdoelrueckstaende nutzbar zu machen. Durch eine homogene Verteilung der Kunststoffpartikel im Erdoelrueckstand soll ein moeglichst kurzer Transportweg zwischen Wasserstoff-Donor und -Akkzeptor, eine ausreichend grosse Reaktionsoberflaeche und eine fuer weitere Verarbeitungsschritte notwendige stabile Mischung erreicht werden. Ebenso interessant wie die Homogenitaet solcher Gemische ist auch der Einfluss der eingemengten Polymerteilchen auf die Kolloidstabilitaet des Erdoelrueckstandes und die physikalisch-chemischen Eigenschaften der Mischungen. Im Hinblick auf eine technische Weiterverarbeitung werden die Gemische besonders auf ihre Stabilitaet bei erhoehten Temperaturen (Heisslagerstabilitaet), ihr Fliessverhalten sowie ihr Reaktionsverhalten waehrend der Pyrolyse untersucht. (orig.)

  1. Lifetime assessment of thick-walled components made of nickel-base alloys under near-service loading conditions; Lebensdauerbewertung dickwandiger Bauteile aus Nickelbasislegierungen unter betriebsnahen Beanspruchungen

    Energy Technology Data Exchange (ETDEWEB)

    Hueggenberg, Daniel

    2015-11-06

    Until 2050 the renewable energies should provide 80% of the power in Germany according to Renewable Energy law. Due to that reason the conventional power plants are not used for base load, but rather for the supply of average and peak load. The change of the operating mode leads to shorter times at stationary temperatures and the number of faster start-ups/shut-downs of the power plants will increase. As a result of this the components are exposed to an interacting load of creep and fatigue which reduces the lifetimes. The aim of this thesis is the development and verification of a lifetime assessment procedure for components made of the nickel-base alloys Alloy 617 mod. and Alloy 263 under creep fatigue loading conditions based on numerical phenomenological models and on the approaches of different standards/recommendations. The focus lies on two components of the high temperature material test rig II (HWT II), a header made of Alloy 617 mod. and Alloy 263 as well as a formed part made of Alloy 617 mod. For the basis characterization of the HWT II melts, specimens of the Alloy 617 mod. and Alloy 263 are tested in uniaxial tensile tests, (creep-)fatigue tests, creep tests and charpy tests in a temperature range between 20 C and 725 C. From the comparisons of the test results and the material specifications respectively the results of the projects COORETEC DE4, MARCKO DE2 and MARCKO700 no deviations were obvious for both materials with the exception of the creep test results with Alloy 617 mod. material. The creep tests with Alloy 617 mod. material of the HWT II melt show differences regarding the deformation and damage behavior. In addition to the basis characterization tests some complex lab tests for the characterization of the material behavior under creep-fatigue and multiaxial loading conditions were conducted. The developments of the microstructure, the precipitations as well as the structure of dislocations are investigated in the light optical microscope

  2. Climatic change and the effects on the marine ecosystem around the island of Sylt. Final report; Das marine Oekosystem um Sylt unter veraenderten Klimabedingungen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Lackschewitz, D.; Menn, I.; Reise, K.

    2000-05-01

    Climatic warming of 1.5 to 2.5 C with a higher water temperature may only slightly change the species spectrum of the intertidal zone of the island of Sylt (North Sea). This is shown by a comparison with tidal flats of the French Atlantic coast. Stronger effects are expected from a sea level rise and an increase in hydrodynamic forces. This may result in a decrease of eelgrass and mussel beds. On the high intertidal zone muddy flats will be replaced by sandy flats due to wave action. Enhanced erosion at the Wadden Sea shoreline will probably entail its continued petrification to prevent further losses. This will cause a decrease of natural habitats with their specific assemblages, and the esthetic appeal of the Wadden Sea will decrease too. It is proposed that sand replenishment on the Wadden Sea shoreline will better preserve the natural sequence of biotopes on the tidal flats. The erosive beach on the seaward side of the island of Sylt is both focal place for tourist recreation, and the site of a highly diverse interstitial fauna. This fauna will be able to re-establish itself three months after a campaign of sand replenishment. Sand replenishment was found to be an effective way to compensate beach erosion and, due to the quick re-establishment of the fauna, it may be regarded as an acceptable method of coastal defense from an ecological perspective. (orig.) [German] Bei einer Klimaerwaermung um 1,5 bis 2,5 C wird der direkte Einfluss hoeherer Wassertemperatur das biologische Artenspektrum im Sylter Gezeitenbereich nicht wesentlich veraendern. Dies ergibt ein Vergleich mit Watten der franzoesischen Atlantikkueste. Bedeutender sind voraussichtlich Auswirkungen hoeherer Wasserstaende und einer zunehmenden Hydrodynamik. Seegraswiesen und Muschelbaenke werden dadurch im Wattbereich abnehmen. In Ufernaehe werden schlickige von sandigen Watten verdraengt. Einer verstaerkten Erosion an ungeschuetzten Wattufern wird voraussichtlich mit weiteren Befestigungen begegnet

  3. Experimental investigations on the coolability of prototypical particle beds with respect to reactor safety; Experimentelle Untersuchungen der Kuehlbarkeit prototypischer Schuettungskonfigurationen unter dem Aspekt der Reaktorsicherheit

    Energy Technology Data Exchange (ETDEWEB)

    Leininger, Simon

    2017-02-22

    In case of a severe accident in a light water reactor, continuous unavailability of cooling water to the reactor core may result in overheating of the fuel elements and finally the loss of core integrity. Under such conditions, a structure of heat-releasing particles of different size and shape may be formed by fragmentation of molten core material in several stages of the accident. The long-term coolability of such beds is of prime im-portance to avoid any damage to the reactor pressure vessel or even a release of fission products to the environment. In the frame of this work, specific experiments were con-ducted under prototypical conditions employing the existing DEBRIS test facility in order to gain further knowledge about the thermohydraulic behavior of such beds. In steady state boiling experiments, the pressure gradients in particle beds were meas-ured both for one- and multi-dimensional cooling water flow conditions and compared with one another in order to assess the flow behavior inside the bed. For these different flow conditions as well as for stratified bed configurations, the maximum removable heat flux densities were determined in the dryout experiments. E. g., it was found that an axial stratification of the permeability can significantly reduce the bed's coolability. For the first time, the quenching behavior of dry, superheated beds was investigated at elevated system pressure up to 0.5 MPa. In these experiments, the effect of system pressure on the coolability was quantified by means of the quenching time (time period to cool down the bed to saturation temperature). The investigated particle beds mainly consisted of non-spherical particles with well-defined geometry (cylinders and screws). It was shown that the effect of the particles geometry on the flow in a particle bed can be best estimated by using an equivalent particle diameter calculated for monodisperse particle beds from the product of the Sauter diameter and a shape factor and for

  4. Productivity of agricultural surfaces in the eastern parts of Germany under the influence of climatic changes; Die Ertragsfaehigkeit ostdeutscher Ackerflaechen unter Klimawandel

    Energy Technology Data Exchange (ETDEWEB)

    Wechsung, Frank; Gerstengarbe, Friedrich-Wilhelm; Lasch, Petra; Luettger, Andrea (eds.)

    2008-12-15

    More than most other economic sectors agriculture depends on climatic conditions. This report presents an analysis of possible climate change effects on Eastern Germany's agriculture. It suggests that the risk of Eastern Germany's acreage losing in value is low. Negative regional impacts of climate change could be countered by appropriate adaptation measures, crop yields in many areas could even be raised and yield losses might be of set by counteracting price increases on the world market. The projection is based on a regional climate scenario. Using the statistical scenario-model STAR II available large scale projections from climate change global circulation models for middle Europe were downscaled to the existing network of East-German weather stations. The available weather records for the period 1951 to 2003 were extended for the scenario period 2004-2055. For the extension, a general increase of the average annual temperature in Eastern Germany by up to 2.7 degrees Celsius (4.8 degrees Fahrenheit) was assumed until the middle of the 21st century. The increase in temperature was triggered by a rise in atmospheric CO2 concentration from 386 at present to 542 ppm in 2055. The scenario model STAR II was used to derive the associated changes of the other major climate variables. Following the results the average annual rainfall is projected to decrease only marginally. However, shift of rainfall patterns is to be expected. Summertime rainfall will probably decrease while wintertime rainfall is likely to increase. This trend can already be monitored today and will continue as a tendency into the future. According to the projections this development will be interrupted infrequently, though, by relatively humid phases with comparatively high amounts of rainfall during the summer months. Based on this scenario, the future crop yield potentials were evaluated for the summer crop maize and the winter crop wheat in Eastern Germany. The evaluation used

  5. Temperature Pill

    Science.gov (United States)

    1988-01-01

    Ingestible Thermal Monitoring System was developed at Johns Hopkins University as means of getting internal temperature readings for treatments of such emergency conditions as dangerously low (hypothermia) and dangerously high (hyperthermia) body temperatures. ITMS's accuracy is off no more than one hundredth of a degree and provides the only means of obtaining deep body temperature. System has additional applicability in fertility monitoring and some aspects of surgery, critical care obstetrics, metabolic disease treatment, gerontology (aging) and food processing research. Three-quarter inch silicone capsule contains telemetry system, micro battery, and a quartz crystal temperature sensor inserted vaginally, rectally, or swallowed.

  6. Implementation of new concepts for space HVAC systems in domestic buildings in consideration of cost, consumption and user comfort. Final report; Umsetzung neuer Konzepte der technischen Gebaeudeausruestung im Wohnungsbau unter Beruecksichtigung von Kosten, Verbraeuchen und Nutzerkomfort. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, F.; Sucic, D.; Wendler, M.

    1998-03-01

    The goal of this project was the development of a set of tools for the selection of optimal concepts for HVAC-systems in housing buildings. Several factors are considered. They include technical feasibility, costs for investment, maintenance and operation, energy concumption, environmental impacts and user comfort. It is intended with the help of these tools to identify the most important factors which influence energy consumption and to suggest simple and cost effective measures to reduce energy consumption. Measures include improvements of the envelope, changes in the HVAC-system and its operation according to the needs to the inhabitants of the building. This report describes these components of this tool set which were developed in the frame of the project WohnKomfort. It lists data and rules chosen. In addition we report experiences which we gained with an prototypical implementation. This implementation allows load calculations for more than 60.000 different buildings applying EN 802 (only one zone model) as calculation method. It also supports selection of heating systems for such buildings by offering an evaluation according to user specified criteria including cost, environment and comfort. (orig./MM) [Deutsch] Ziel des Vorhabens war die Entwicklung eines Instrumentariums zur Auswahl optimaler Konzepte fuer technische Anlagen in Wohngebaeuden unter Beruecksichtigung der Faktoren technische Machbarkeit, Erstellungs-, Betriebskosten, Energieverbrauch, Umweltbelastung und Nutzerkomfort. Mit Hilfe dieses Instrumentariums soll es moeglich werden, die Haupteinflussfaktoren fuer den Energieverbrauch anzugeben und Vorschlaege fuer einfache und kostenguenstige Massnahmen zu seiner Reduzierung auf der Seite des Gebaeudes (bauliche Massnahmen) und der Anlage (technische Massnahmen, Nutzerverhalten) anzugeben. In diesem Bericht beschreiben wir die im Vorhaben entwickelten Komponenten des Instrumentariums, die zugrundeliegenden Daten und Regeln sowie Erfahrungen, die

  7. Calculations of an unsteady flow through a hydraulic axial turbine with reference to interaction between stator and rotor; Instationaere Berechnung einer hydraulischen Axialturbine unter Beruecksichtigung der Interaktion zwischen Leit- und Laufrad

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, C.

    2001-07-01

    The objective of this study is the development of an algorithm enabling coupling of nonmatching computational grids to carry out calculations of an unsteady flow through a hydraulic axial turbine with reference to interaction between stator and rotor. The algorithm should offer the possibility to operate the computational grids in a fixed position relative to each other as well as in relative movement. Furthermore, the calculation should be feasible with separate grids in parallel and different frames of reference. Employing selected examples this method is investigated in detail the results are compared with performed measurements. The unsteady numerical examination of the coupling process is carried out with different examples; especially the interaction effects between stator, rotor and draft tube of a hydraulic axial turbine are observed. In addition, the effect of tip clearance of the mean flow is described. Extensive model tests using the axial turbine have been performed at the Institute for Fluid Mechanics and Hydraulic Machinery, IHS. Flow time dependent velocities have been measured with a Laser Doppler Velocimeter placed at midspan of the blading. Periodical changes in static pressure have been recorded at different locations near the wall of the turbine casing. These measurements serve as reference for the comparison with results derived from the unsteady calculations. The confrontation of the time-dependent fluctuations of the flow quantities and the calculation of the efficiency of the turbine resulting from the simulation results allow a comparison in absolute terms. (orig.) [German] Fuer die instationaere Berechnung einer hydraulischen Axialturbine unter Beruecksichtigung der Interaktion zwischen Leit- und Laufrad wird ein Algorithmus zum Koppeln von nichtpassenden Berechnungsnetzen entwickelt. Diese Berechnungsnetze sollen zueinander ortsfest sein oder auch eine Relativbewegung zueinander haben koennen. Sie sollen ausserdem und in unterschiedlichen

  8. A survey of anticoagulation practice among German speaking microsurgeons – Perioperative management of anticoagulant therapy in free flap surgery [Erhebung über die antikoagulatorische Praxis unter deutschsprachigen Mikrochirurgen – Perioperatives Management der antikoagulatorischen Therapie bei freien Lappentransplantaten

    Directory of Open Access Journals (Sweden)

    Jokuszies, Andreas

    2012-02-01

    Full Text Available [english] Background: Anticoagulation is a crucial element in microsurgery. Although various clinical studies and international surveys have revealed that anticoagulation strategies can vary and result in similar outcomes, anticoagulative regimen are far away from standardization. In Germany and german speaking countries standardized anticoagulation protocols concerning free flap surgery do not exist so far. Methods: To evaluate the current practice of clinics in Germany, Austria and Switzerland with specialization in microsurgery we performed a questionnaire surveying the perioperative regimen of anticoagulant and antiplatelet therapy in free flap surgery. The microsurgeons were interrogated on several anticoagulant, rheologic and antiplatelet medications, their dosage and perioperative frequency of application pre-, intra- and postoperative.Results: The questionnaire revealed that the used antithrombotic and perioperative regimens varied from department to department presumably based on the personal experience of the surgeon. Multiple approaches are used with a wide range of anticoagulants used either alone or in combination, with different intervals of application and different dosages. Conclusion: Therefore consensus meetings should be held in future leading to conduct prospective multicenter studies with formulation of standardized anticoagulative and perioperative protocols in microsurgery reducing flap failure to other than pharmacologic reasons.[german] Hintergrund: Die Antikoagulation stellt ein zentrales Element in der Mikrochirurgie dar. Zahlreiche klinische Studien und internationale Erhebungen zu antikoagulatorischen Strategien weisen eine grosse Varianz bei vergleichbaren Resultaten nach, entbehren jedoch einer Standardisierung. Auch in Deutschland und deutschsprachigen Ländern fehlen bislang standardisierte Regime zur Antikoagulation in der Mikrochirurgie.Methodik: Zur Erhebung der antikoagulatorischen Praxis unter

  9. Ungarn seit der Wahl: Demokratie unter Druck

    NARCIS (Netherlands)

    Freyberg-Inan, A.; Varga, M.

    2011-01-01

    Die Verfasser zeigen, dass die Orban-Regierung legitime Probleme benennt, wie etwa Ungarns extrem niedrige Beschäftigungsrate, die mit zu den großen wirtschaftliche Schwierigkeiten des Landes beiträgt. Doch packt sie die identifizierten Probleme zu oft auf eine Weise an, die ganz nebenbei dem

  10. Temperature metrology

    Science.gov (United States)

    Fischer, J.; Fellmuth, B.

    2005-05-01

    The majority of the processes used by the manufacturing industry depend upon the accurate measurement and control of temperature. Thermal metrology is also a key factor affecting the efficiency and environmental impact of many high-energy industrial processes, the development of innovative products and the health and safety of the general population. Applications range from the processing, storage and shipment of perishable foodstuffs and biological materials to the development of more efficient and less environmentally polluting combustion processes for steel-making. Accurate measurement and control of temperature is, for instance, also important in areas such as the characterization of new materials used in the automotive, aerospace and semiconductor industries. This paper reviews the current status of temperature metrology. It starts with the determination of thermodynamic temperatures required on principle because temperature is an intensive quantity. Methods to determine thermodynamic temperatures are reviewed in detail to introduce the underlying physical basis. As these methods cannot usually be applied for practical measurements the need for a practical temperature scale for day-to-day work is motivated. The International Temperature Scale of 1990 and the Provisional Low Temperature Scale PLTS-2000 are described as important parts of the International System of Units to support science and technology. Its main importance becomes obvious in connection with industrial development and international markets. Every country is strongly interested in unique measures, in order to guarantee quality, reproducibility and functionability of products. The eventual realization of an international system, however, is only possible within the well-functioning organization of metrological laboratories. In developed countries the government established scientific institutes have certain metrological duties, as, for instance, the maintenance and dissemination of national

  11. Temperature metrology

    International Nuclear Information System (INIS)

    Fischer, J; Fellmuth, B

    2005-01-01

    The majority of the processes used by the manufacturing industry depend upon the accurate measurement and control of temperature. Thermal metrology is also a key factor affecting the efficiency and environmental impact of many high-energy industrial processes, the development of innovative products and the health and safety of the general population. Applications range from the processing, storage and shipment of perishable foodstuffs and biological materials to the development of more efficient and less environmentally polluting combustion processes for steel-making. Accurate measurement and control of temperature is, for instance, also important in areas such as the characterization of new materials used in the automotive, aerospace and semiconductor industries. This paper reviews the current status of temperature metrology. It starts with the determination of thermodynamic temperatures required on principle because temperature is an intensive quantity. Methods to determine thermodynamic temperatures are reviewed in detail to introduce the underlying physical basis. As these methods cannot usually be applied for practical measurements the need for a practical temperature scale for day-to-day work is motivated. The International Temperature Scale of 1990 and the Provisional Low Temperature Scale PLTS-2000 are described as important parts of the International System of Units to support science and technology. Its main importance becomes obvious in connection with industrial development and international markets. Every country is strongly interested in unique measures, in order to guarantee quality, reproducibility and functionability of products. The eventual realization of an international system, however, is only possible within the well-functioning organization of metrological laboratories. In developed countries the government established scientific institutes have certain metrological duties, as, for instance, the maintenance and dissemination of national

  12. temperature overspecification

    Directory of Open Access Journals (Sweden)

    Mehdi Dehghan

    2001-01-01

    Full Text Available Two different finite difference schemes for solving the two-dimensional parabolic inverse problem with temperature overspecification are considered. These schemes are developed for indentifying the control parameter which produces, at any given time, a desired temperature distribution at a given point in the spatial domain. The numerical methods discussed, are based on the (3,3 alternating direction implicit (ADI finite difference scheme and the (3,9 alternating direction implicit formula. These schemes are unconditionally stable. The basis of analysis of the finite difference equation considered here is the modified equivalent partial differential equation approach, developed from the 1974 work of Warming and Hyett [17]. This allows direct and simple comparison of the errors associated with the equations as well as providing a means to develop more accurate finite difference schemes. These schemes use less central processor times than the fully implicit schemes for two-dimensional diffusion with temperature overspecification. The alternating direction implicit schemes developed in this report use more CPU times than the fully explicit finite difference schemes, but their unconditional stability is significant. The results of numerical experiments are presented, and accuracy and the Central Processor (CPU times needed for each of the methods are discussed. We also give error estimates in the maximum norm for each of these methods.

  13. Development and application of dynamic MR-imaging for evaluation of perfusion changes in rectal carcinoma during a course of radiotherapy in clinical use. Preliminary results; Entwicklung und Anwendung dynamischer MRT-Messungen zur Evaluierung von Perfusionsveraenderungen bei Rektumkarzinomen unter Bestrahlung in der klinischen Routine. Erste Ergebnisse

    Energy Technology Data Exchange (ETDEWEB)

    Vries, A. de; Griebel, J.; Gneiting, T.; Hoflehner, J.; Brandl, M.; Lukas, P. [Leopold-Franzens-Univ. Innsbruck (Austria). Universitaetsklinik fuer Strahlentherapie - Radioonkologie; Judmaier, W.; Kremser, C.; Schocke, M.; Aichner, F. [Leopold-Franzens-Univ. Innsbruck (Austria). Inst. fuer Magnetresonanztomographie; Peer, S.; Rettl, G. [Leopold-Franzens-Univ. Innsbruck (Austria). Universitaetsklinik fuer Radiodiagnostik I; Oefner, D. [Leopold-Franzens-Univ. Innsbruck (Austria). Universitaetsklinik fuer Chirurgie; Debbage, P. [Leopold-Franzens-Univ. Innsbruck (Austria). Inst. fuer Histologie und Embryologie

    1999-11-01

    procedures. (orig.) [German] Ziel: Entwicklung und Anwendung dynamischer Magnetresonanztomographiemessungen zur Erhebung von Perfusionsparametern bei Rektumkarzinomen unter Bestrahlung in der klinischen Routine. Patienten und Methode: Bei Rektumkarzinompatienten (n=8), die sich einer praeoperativen kombinierten Radiochemotherapie unterzogen, wurden Perfusionsdaten erhoben. An einem 1,5-Tesla-Ganzkoerperkernspintomographen wurden ultraschnelle T1-Mapping-Sequenzen zum Erhalt von T1-Maps mit Intervallen von 14 und 120 Sekunden implementiert. Die Messzeit der dynamischen Messungen betrug 40 Minuten. Die Messschicht (Schichtdicke 5 mm) wurde so gewaehlt, dass sowohl Tumor als auch arterielle Gefaesse dargestellt wurden. Gadolinium-DTPA-(Gd-DTPA-)Konzentrations-Zeit-Kurven wurden nach einem prolongierten Bolus im arteriellen Blut und im Tumor berechnet. Die angewendete Methode erlaubte eine raeumliche Aufloesung von 2x2x5 mm und eine zeitliche Aufloesung von 14 Sekunden. Die Messdaten wurden vor und in konstanten Intervallen waehrend Therapie erhoben. Ergebnisse: Die raeumliche und zeitliche Aufloesung der T1-Maps war ausreichend, um Areale mit unterschiedlicher Kontrastmittelkinetik innerhalb des Tumors zu erfassen sowie die grossen Beckenarterien sicher zu identifizieren. Bei sechs Patienten konnten Gd-DTPA-Konzentrationskurven im Tumor unter Therapie erhoben werden. Der Perfusionsindex (Pi) versus Strahlendosis zeigte eine signifikante Zunahme in der ersten oder zweiten Woche der Bestrahlung, bevor er entweder kontinuierlich absank oder nach anfaenglichem Abfall einen erneuten Anstieg aufwies. Der durchschnittliche Pi-Ausgangswert betrug 0,16 ({+-}0,049), das durchschnittliche Pi-Maximum war 0,23 ({+-}0,058). Die relativen Perfusionsveraenderungen betrugen zwischen 20 und 83%. Schlussfolgerung: Unsere Ergebnisse zeigen, dass sich die verwendete Methode zur Erfassung von Perfusionsparametern unter Bestrahlung eignet und in der klinischen Routine anwendbar ist. In der Zukunft

  14. Briquetting properties of sponge iron at high temperature; Das Heissbrikettierverhalten von Eisenschwamm

    Energy Technology Data Exchange (ETDEWEB)

    Naundorf, W. [TU Bergakademie Freiberg (Germany); Trommer, D. [TU Bergakademie Freiberg (Germany); Guenter, H. [Koeppern Aufbereitungstechnik GmbH und Co. KG (Germany); Kuschel, M. [TU Bergakademie Freiberg (Germany)

    1994-12-31

    In the briquetting laboratory of the TU Bergakademie Freiberg hot briquetting of sponge iron was investigated. It was found that on increasing the pressing temperature in the range of 600 C to 1000 C a sudden improvement of briquette quality occurs. Applying a pressure of p = 200 MPa and a pressing temperature of above 700 C practically all kinds of sponge iron can be densified into briquettes with a density of {>=} 5 g/cm{sup 3}. As the pressing temperature increases the thickness expansion of the briquettes decreases, turning into a shrinkage process above 600 C. As regards the effect of grain size of sponge iron on briquette quality it was found that coarser fractions of the raw material lead to more dense and harder briquetts under the same briquetting conditions. Fine material with a grain size < 6 mm deteriorates briquette quality. Further more, it has been established that there is a order of rank in the briquettability. (orig.) [Deutsch] Im Brikettierlabor der TU Bergakademie Freiberg wude das Heissbrikettierverhalten von Eisenschwaemmen untersucht. Es wurde gefunden, dass mit steigender Verpressungstemperatur der Eisenschwaemme im Bereich 600 C bis 1000 C eine sprunghafte Verbesserung der Brikettqualitaet erreicht wird. Bei Anwendung eines Pressdruckes von p = 200 MPa und einer Verpressungstemperatur oberhalb 700 C lassen sich faktisch alle Eisenschwaemme zu Briketts mit einer Rohdichte {>=} 5 g/cm{sup 3} verdichten. Mit steigender Verpressungstemperatur vermindert sich die Dickenexpansion der Briketts. Oberhalb 600 C setzt eine Schrumpfung der Briketts ein. Zum Einfluss der Koernung der Eisenschwaemme auf die Brikettqualitaet wurde festgestellt, dass sich groebere Produktfraktionen unter gleichen Brikettierbedingungen zu dichteren und festeren Briketts verpressen lassen. Feingut mit der Korngroesse < 6 mm verschlechtert die Qualitaet der Briketts. Es konnte weiter festgestellt werden, dass eine Rangfolge im Brikettiercharakter der Eisenschwaemme besteht

  15. Development and application of a NaNiCl{sub 2}-battery for industrial trucks regarding the requirements cycle life, safety and reliability. Final report; Entwicklung und Erprobung einer NaNiCl{sub 2}-Batterie fuer Flurfoerderzeuge unter besonderer Beruecksichtigung der Aspekte Lebensdauer, Sicherheit und Zuverlaessigkeit. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, H.; Beyermann, G.; Bulling, M.

    1996-07-01

    Two NaNiCl{sub 2}-battery types including the battery controller and peripheral equipment have been developed for the application in fork lift trucks and driverless transportation. The batteries have been tested and evaluated on bench testing as well as in fork lift trucks and driverless trucks in practical application. The field tests have been performed by the subcontractors Still, Mercedes-Benz and Indumat. All test results have shown that the NaNiCl{sub 2}-battery (ZEBRA-battery) is well suited for the application in industrial traction. A series development together with a cost reduction programme have to be performed ahead of the introduction of the ZEBRA-battery into the market for industrial traction batteries. (orig.) [Deutsch] Im Rahmen des Vorhabens wurden zwei NaNiCl{sub 2}-Batterietypen, eine fuer die Anwendung in Gabelstaplern, die andere fuer den Einsatz in fahrerlosen Transportsystemen (FTS), einschliesslich des Batteriesteuergeraetes und der Batterieperipherie entwickelt. Die Batterien wurden auf Teststaenden im Labor sowie in Gabelstaplern und FTS unter Praxisbedingungen erprobt. Der praktische Einsatz erfolgte bei den Unterauftragnehmern Still, Mercedes-Benz und Indumat. Die Ergebnisse haben gezeigt, dass die NaNiCl{sub 2}-Batterie (ZEBRA-Batterie) fuer die Anwendung in Gabelstaplern und FTS geeignet ist. Insbesondere wurde nachgewiesen, dass die NaNiCl{sub 2}-Batterie im Gegensatz zu anderen Batteriesystemen einen Zweischichtbetrieb von Gabelstaplern ohne Batteriewechsel ermoeglicht. Vor Einfuehrung der ZEBRA-Batterie in den Flurfoerdermarkt muss die Serienentwicklung bei gleichzeitiger Senkung der Herstellkosten durchgefuehrt werden. (orig.)

  16. Power to gas to relieve the electricity distribution networks. Continuation of the study ''Benefit of smart grid concepts taking into account the PtG technology''; Power-to-Gas zur Entlastung der Stromverteilungsnetze. Fortsetzung der Studie ''Nutzen von Smart-Grid-Konzepten unter Beruecksichtigung der PtG-Technologie''

    Energy Technology Data Exchange (ETDEWEB)

    Huettenrauch, Jens; Zoellner, Sylvana; Mueller-Syring, Gert [DBI Gastechnologisches Institut gGmbH, Freiberg (Germany); and others

    2015-07-01

    One of the main challenges in the energy transition is to integrate the increasing based on volatile renewable energy generated power in market and network. Based on actual distribution networks in Emsland in the study presented below was investigated, what contribution an intelligent coupling of electricity and gas distribution networks by means of power to gas (PtG) systems can do to solve this challenge. The investigations have shown, among other things, that the network expansion costs in particular can be significantly reduced by the coupling when otherwise an oversizing would be done by discrete power grid expansion measures. [German] Eine der wesentlichen Herausforderung bei der Energiewende besteht darin, die zunehmend auf volatilen erneuerbaren Energien basierende Stromerzeugung in Markt und Netz zu integrieren. Anhand realer Verteilungsnetze im Emsland wurde in der im Folgenden vorgestellten Studie untersucht, welchen Beitrag eine intelligente Kopplung von Strom- und Gasverteilungsnetzen mittels Power-to-Gas (PtG)-Anlagen zur Loesung dieser Herausforderung leisten kann. Die Untersuchungen haben unter anderem gezeigt, dass durch die Kopplung die Netzausbaukosten insbesondere dann signifikant reduziert werden koennen, wenn andernfalls eine Ueberdimensionierung durch diskrete Stromnetzausbaumassnahmen erfolgen wuerde.

  17. Temperature simulations in hyperthermia treatment planning of the head and neck region. Rigorous optimization of tissue properties

    Energy Technology Data Exchange (ETDEWEB)

    Verhaart, Rene F.; Rijnen, Zef; Verduijn, Gerda M.; Paulides, Margarethus M. [Erasmus MC - Cancer Institute, Department of Radiation Oncology, Hyperthermia Unit, Rotterdam (Netherlands); Fortunati, Valerio; Walsum, Theo van; Veenland, Jifke F. [Erasmus MC, Departments of Medical Informatics and Radiology, Biomedical Imaging Group Rotterdam, Rotterdam (Netherlands)

    2014-12-15

    Vorbehandlung, Entscheidungsfindung und zur Echtzeitanpassung der Behandlung verwendet. In der gegenwaertigen klinischen Praxis basiert die HTP auf Vorhersagen der Energieabsorption. Die Waerme-Dosis-Wirkungs-Beziehung befuerwortet jedoch eine Erweiterung durch Temperaturvorhersagen. Aufgrund der starken thermoregulatorischen Reaktion des Kopf- und Halsgewebes sind fuer die Ausnutzung von Temperatursimulationen region- und temperaturspezifische thermische Gewebeeigenschaften notwendig. Das Ziel dieser Arbeit ist die Entwicklung eines Verfahrens zur patientengruppenspezifischen Optimierung von thermischen Gewebeeigenschaften, basierend auf invasiv gemessenen Temperaturen. Anschliessend soll die mit dieser Methode erreichbare Genauigkeit evaluiert werden. Die Perfusions- und Waermeleitfaehigkeitswerte des thermischen Modells, basierend auf der ''Bioheat Equation'' von Pennes, wurden unter Verwendung der Daten von 17 behandelten Patienten optimiert. Fuer die genaue Bestimmung der Differenz zwischen der gemessenen und simulierten Temperatur (∇T) wurde ein ''Leave-One-Out''-Validierungsverfahren verwendet. Zur Evaluierung der Verbesserung von ∇T unter Verwendung der optimierten Waermeeigenschaftswerte wurden diese mit Werten aus der Literatur, sowohl ohne als auch mit thermischer Belastung, verglichen. Die optimierten Perfusions- und Waermeleitfaehigkeitswerte fuer Tumore, Muskeln und Fett fuehren zu einer Verbesserung der Simulationsgenauigkeit (∇T: 2,1 ± 1,2 C) im Vergleich zu herkoemmlichen Verfahren ohne (∇T: 12,7 ± 11,1 C) und mit thermischer Belastung (∇T: 4,4 ± 3,5 C). Die vorgestellte Methode fuehrt zu patienten-gruppenspezifischen Temperatureigenschaftswerten, welche die Simulationsgenauigkeit in der anspruchsvollen Kopf- und Halsregion erheblich verbessern. Simulationen bilden somit eine elegante Ergaenzung zu invasiven Messungen. Die rigorose ''Leave-One-Out''-Validierung zeigt, dass Verbesserungen

  18. Damage and service life of nickel-base alloys under thermal-mechanical fatigue stress at different phase positions; Schaedigung und Lebensdauer von Nickelbasislegierungen unter thermisch-mechanischer Ermuedungsbeanspruchung bei verschiedenen Phasenlagen

    Energy Technology Data Exchange (ETDEWEB)

    Guth, Stefan

    2016-07-01

    This work considers the behaviour of two nickel-base alloys (NiCr22Co12Mo9 and MAR-M247 LC) under thermo-mechanical fatigue loading with varying phase angles between mechanical strain and temperature. The investigations focus on the characterisation of microstructures and damage mechanisms as a function of the phase angle. Based on the results, a life prediction model is proposed.

  19. Total emissivity and spectral emissivity of high-temperature materials; Gesamtemissionsgrad und spektraler Emissionsgrad von Hochtemperaturmaterialien

    Energy Technology Data Exchange (ETDEWEB)

    Neuer, G.; Pohlmann, P.; Schreiber, E.

    1998-05-01

    A new emissivity measurement device with inductive sample heating is described. The disc shaped samples can be measured between 800 C and 2000 C in vacuum or in each available gas atmosphere. Two kinds of surface temperature measurement methods are described, one by measuring in a blackbody hole and one by measuring at the surface without additional measures to correct emissivity. Total normal and spectral emissivity at wavelengths between 0,5 {mu}m and 8,3 {mu}m of various high temperature materials like platinum and Pt-Rh-alloys, siliconcarbide and molybdenum disilicide have been measured. From the investigated materials a few have been selected as reference samples for comparative emissivity measurements fullfilling the requirement of stability on air up to 400 C to 1000 C in order to ensure reproducibility of the results at different measurement conditions in air and in vacuum. (orig.) [Deutsch] Der Aufbau einer neuen Messapparatur fuer Emissionsgradmessungen bei Temperaturen zwischen 1000 C und 2000 C wird beschrieben. Die scheibenfoermigen Proben werden induktiv beheizt, und die Messungen koennen entweder in Vakuum oder einer beliebigen Gasatmosphaere durchgefuehrt werden. Es werden zwei verschiedene Verfahren zur Bestimmung der Oberflaechentemperatur bechrieben, wobei entweder in einer oder direkt an der Oberflaeche ohne zusaetzliche Massnahmen zur Emissionsgradkorrektur gemessen wird. An verschiedenen Hochtemperaturwerkstoffen wie Platin und Platin-Rhodium-Legierungen, Siliziumkarbid mit unterschiedlichen Herstellungsarten und Molybdaen-Disilizid wurden der Gesamtemissionsgrad und der spektrale Emissionsgrad bei Wellenlaengen von 0,5 {mu}m bis 8,3 {mu}m senkrecht zur Oberflaeche gemessen. Aus den untersuchten Materialien wurden solche als Referenzmaterialien fuer vergleichende Emissionsgradmessungen ausgewaehlt, die sowohl im Vakuum als auch in Luft und bei Temperaturen von 1400 C bis 1600 C unter verschiedenen Messbedingungen reproduzierbare Ergebnisse

  20. Body temperature norms

    Science.gov (United States)

    Normal body temperature; Temperature - normal ... Morrison SF. Regulation of body temperature. In: Boron WF, Boulpaep EL, eds. Medical Physiology . 3rd ed. Philadelphia, PA: Elsevier; 2017:chap 59. Sajadi MM, Mackowiak ...

  1. Survey of risks related to static magnetic fields in ultra high field MRI; Bestandsaufnahme zu Risiken durch statische Magnetfelder im Zusammenhang mit der Ultrahochfeld-MRT

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, H.E. [Max-Planck-Inst. fuer Kognitions- und Neurowissenschaften, Leipzig (Germany); Cramon, D.Y. von [Max-Planck-Inst. fuer Kognitions- und Neurowissenschaften, Leipzig (Germany); Max-Planck-Inst. fuer Neurologische Forschung, Koeln (Germany)

    2008-04-15

    In magnetic resonance imaging (MRI), substantial improvements with respect to sensitivity are expected due to the development of so-called ultra high field scanners, i.e., whole-body scanners with a magnetic field strength of 7 T or above. Users of this technology need to evaluate this benefit for potential risks since commercially available systems are not certified as a medical device for human use. This review provides a detailed survey of static field bioeffects related to the exposure of subjects being scanned, to occupational exposure, and to exposure of the general public under consideration of current standards and directives. According to present knowledge, it is not expected that exposure of human subjects to static magnetic fields of 7 T implies a specific risk of damage or disease provided that known contraindications are observed. The available database does not permit definition of exact thresholds for harmful effects. However, experience from previous application of ultra high field MRI indicates that transient phenomena, such as vertigo, nausea, metallic taste, or magnetophosphenes, are more frequently observed. In particular, movements in the field or the gradient of the fringe field seem to lead to detectable effects. Besides such observations, there is a strong demand for systematic investigation of potential interaction mechanisms related to static field exposure during MRI examinations. (orig.)

  2. De verkeersonveiligheid van voetgangers, fietsers en bromfietsers binnen de bebouwde kom in cijfers. Een statische beschrijving van de landelijke gegevens betreffende verkeersongevallen en verkeersslachtoffers.

    NARCIS (Netherlands)

    Blokpoel, A.

    1978-01-01

    A statistical description is given of Dutch national data of traffic accidents and traffic victims. The purpose of the study was to review the magnitude and development of the traffic unsafety of pedestrians, cyclists and moped riders.

  3. {sup 31}P-MR-spectroscopy of the skeletal muscles under load: demonstration of normal energy metabolism compared to different neuromuscular diseases; {sup 31}P-MR-Spektroskopie der peripheren Skelettmuskulatur unter Belastung: Darstellung des normalen Energiestoffwechsels im Vergleich zu metabolischen Muskelerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Block, W.; Traeber, F.; Kuhl, C.K.; Keller, E.; Rink, H.; Schild, H.H. [Bonn Univ. (Germany). Radiologische Klinik; Lamerichs, R. [Philips Medical Systems, Best (Netherlands); Karitzky, J. [Bonn Univ. (Germany). Neurologische Klinik

    1998-03-01

    Purpose: {sup 31}P-MR spectroscopy of skeletal muscle under ecercise was used to obtain the range of normal variation and comparison was made for different neuromascular diseases. Methods: 41 examinations of 24 volunteers and 41 investigations in 35 patients were performed on 1.5 T MR systems (Gyroscan S15 und S15/ACSII, Philips). Localised {sup 31}P-MR spectra of the calf muscle were obtained in time series with a resolution of 12 s. Results: Two types of muscle energy metabolism were identified from the pattern of spectroscopic time course in volunteers: While the first group was characterised by a remarkable decline to lower pH values during exercise, the second group showed only small pH shifts (minimum pH: 6.48{+-}0.13 vs 6.87{+-}0.07, p<10{sup -6}) although comparable workload conditions were maintained. The pH-values correlated well with blood lactate analysis. Patients with metabolic disorders and chronic fatigue syndrome (CFS) showed decreased resting values of PCr/(PCr+P{sub i}) and increased pH levels during exercise. PCr recovery was significantly delayed (0.31 vs 0.65 min{sup -1}, p<0.00005) in metabolic muscle disorders but was normal in CFS patients. Conclusion: Findings in volunteers indicate utilisation of different metabolic pathways which seems to be related to the fibre type composition of muscle. Reduced resting levels for PCr/(PCr+P{sub i}), altered pH time courses, and decreased PCr recovery seem to be helpful indicators for diagnosis of metabolic muscle disorders. (orig./MG) [Deutsch] Ziel: Bestimmung der Bandbreite des gesunden Energiestoffwechsels der peripheren Skelettmuskulatur mit Hilfe der {sup 31}P-MR-Spektroskopie als Grundlage der Diagnostik neuromuskulaerer Erkrankungen. Methoden: In Mehrfachuntersuchungen an 24 Probanden und 35 Patienten in 1,5 T MR-Systemen (Gyroscan S15 und S15/ACSII, Philips) wurden {sup 31}P-MR-Spektren unter Belastung akquiriert. Ergebnisse: Die Probanden liessen sich streng in zwei Gruppen einteilen

  4. MC-PELMO 3.0 - a computer model to estimate groundwater contamination caused by leaching of wood preservatives from storage sites of treated wood in Germany; Grundwassergefaehrdung durch Holzschutzmittel. MCPELMO 3.0 - ein mathematische Simulationsprogramm zur Abschaetzung der Grundwassergefaehrdung unter Holzlagerflaechen in Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Klein, M. [Fraunhofer-Inst. fuer Molekularbiologie und Angewandte Oekologie, Schmallenberg-Grafschaft (Germany); Herrmann, M. [Umweltbundesamt, Berlin (Germany)

    2004-07-01

    Methods. Based on already in-use versions of the leaching model PELMO, an advanced version (MC-PELMO 3.0) was developed with a specific focus on estimating groundwater contamination under storage sites at wood preserving facilities in Germany. The model processes twenty-two different leaching scenarios that were derived from twelve characteristic soil profiles representing pedological regions in Germany along with recorded meteorological data from nine weather stations. These data are related to geographic distribution of industrial wood preserving activity. The model calculates statistic probabilities of concentrations of wood preservatives in seepage water beneath timber storage sites of regions to be selected by the user. Results and Discussion. The reports provided by MC-PELMO 3.0 include mean average concentrations, 55 to 99 percentiles, and single maximum concentrations for each of the scenarios. The results can be related to the total area of Germany, its forest area or to the density of preservation activity in various regions. Beside concentrations of the parent compounds, those of degradation products may be calculated for the seepage water. Conclusion. The described model is a particularly useful tool for comparative assertion of various wood preservative products under aspects of the exposure of groundwater resources. Comparative assertion is a new element within EU-chemicals policy, for the first time materialized in the biocidal products directive 98/8/EC. Furthermore, the results of model calculations identify vulnerable regions in Germany for which appropriate risk management measures have to be taken in order to protect groundwater from contamination. (orig.) [German] Methoden. Basierend auf bestehenden Versionen des Versickerungsmodells PELMO wurde eine Version speziell fuer die Abschaetzung des Versickerungsverhaltens von Holzschutzmitteln unter Lagerplaetzen von Holz-Impraegnierbetrieben in Deutschland entwickelt. Das stochastische Modell

  5. Suitability of alumina cements for the cementation of boreholes under corrosive conditions, especially at the press fitting of CO{sub 2}; Eignung von Tonerdezementen fuer die Bohrlochzementierung unter korrosiven Bedingungen, insbesondere bei CO{sub 2}-Einpressung. Literaturstudie

    Energy Technology Data Exchange (ETDEWEB)

    Plank, J.; Sieber, R. (comps.) [Technische Univ. Muenchen (Germany). Lehrstuhl fuer Bauchemie

    2011-07-15

    Calcium aluminate cements, also called aluminate cements, are special cements based on calcium aluminates. In construction (especially in dry-mix mortars), they are valued for their remarkably higher acid and corrosion resistance compared to Portland cement. Their high temperature resistance especially qualifies them for refractory cements which are used e.g. as liners in cement rotary kilns. The worldwide production of calcium aluminate cements adds up to about 3 million tons. In oil well cementing, calcium aluminate cements have first been used at the beginning of the 90ies, in fact initially for geothermal wells. Applications in permafrost soils as well as fire-flooding wells came later. The reason for the use in geothermal wells. Applications in permafrost soils as well as fire-flooding wells came later. The reason for the use in geothermal wells were severe problems with API Portland cements affected by hot, carbonic acid rich formation brines. With support from the companies Unocal and Halliburton, the Brookhaven National Laboratory (USA) developed a special cement based on 60 parts by weight of calcium aluminate cement and 40 parts ASTM class F fly ash. This binder is notably CO{sub 2} resistant when mixed with a 25 wt.% Na-polyphosphate solution. Laboratory tests and field applications conclude that this cement is resistant to CO{sub 2} corrosion at temperatures up to 300 C for over 20 years. In 1997, for the first time numerous geothermal wells have been cemented using this cement. They are intact to this day. When this cement hardens at room temperature, amorphous reaction products are formed and the reaction is incomplete. However, at higher temperatures hydroxyapatite, boehmite, Na-P-zeolite, analcime or katoite are formed as crystalline reaction products. The CO{sub 2} resistance of this cement is due to specific chemical reactions. In contact with hot alkaline carbonate solutions, analcime converts to cancrinite, and CO{sub 2} is incorporated into

  6. Distribution of heavy metals in a wood culture water catchment area under the influence of acid deposition as shown by the example of the Soese trough (Western Harz region); Verteilung von Schwermetallen in einem forstlich genutzten Wassereinzugsgebiet unter dem Einfluss saurer Deposition am Beispiel der Soesemulde (Westharz)

    Energy Technology Data Exchange (ETDEWEB)

    Andreae, H. [ed.

    1993-12-31

    This thesis deals with the distribution and turnover of heavy metals in partial terrestrial ecosystems of the water catchment area of the Soese storage dam in the Western Harz region, a forested area affected by acid deposition. The metals investigated are cadmium, chromium, cobalt, copper, nickel, lead and zinc. The work distinguishes three spatial areas: Regional heavy metal pollution is characterized via the establishment of nine deposition measuring sites (recent pollutant stress) in the field or under spruce stands and via cadastre-oriented surveying of element contents and accumulations in humus ground covers and mineral soils (historical pollutant stress). In-soil heavy metal turnovers are documented in five representative sites via investigation of the soil solution (years of measurement 1989-1991). In three sites, heavy metal turnovers are quantified via flow balances for the terrestrial ecosystem and the soil zone free of roots. (orig.) [Deutsch] Die vorliegende Arbeit befasst sich mit der Verteilung und dem Umsatz von Schwermetallen in terrestrischen Teiloekosystemen des bewaldeten, durch saure Deposition beeinflussten Wassereinzugsgebiets der Soese-Talsperre im Westharz. Untersucht werden die Metalle Cadmium, Chrom, Kobalt, Kupfer, Nickel, Blei und Zink. In der Arbeit werden drei raeumliche Ebenen unterschieden: Die regionale Belastung wird ueber die Einrichtung von neun Depositionsmessstellen [rezente Belastung] im Freiland bzw. unter Fichtenbestaenden sowie ueber eine katasterorientierte Erfassung von Element-Gehalten und -Vorraeten in Humusauflagen und Mineralboeden [historische Belastung] charakterisiert. Die bodeninternen Umsaetze der Schwermetalle werden an fuenf repraesentativen Standorten anhand der Untersuchung der Bodenloesung dokumentiert (Messjahre 1989-1991). An drei Standorten werden die Schwermetall-Umsaetze ueber Flussbilanzen fuer das terrestrische Oekosystem und die undurchwurzelte Bodenzone quantifiziert. (orig.)

  7. Development status of the experimental and numerical load analysis of package units CASTOR {sup registered} under drop test conditions; Entwicklungsstand in der experimentellen und numerischen Beanspruchungsanalyse von Versandstuecken der Bauart CASTOR {sup registered} unter Fallpruefbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Voelzer, Walter; Schaefer, Marc; Rumanus, Erkan; Liedtke, Ralph [Gesellschaft fuer Nuklear-Service mbH (Germany); Brehmer, Frank [ITB GmbH (Germany)

    2012-11-01

    The mechanical integrity of package units CASTOR {sup registered} for a 9-m drop test under accident conditions has to be demonstrated according the requirements of IAEA among others. For reduction of the loads the containers have to be equipped with shock absorbers on the bottom and top sides. The determination of loads under drop test conditions can be performed with experimental or numerical methods. Due to the complexity of the load state and the verification of results both methods are usually used for integrity demonstration. The numerical codes have to model the short-term dynamic behavior of the whole container for different drop orientations and temperatures, local stress states have to be quantifiable for assessment. One of the problems is the modeling of the material behavior of wood that is used in the shock absorbers. The so far used energetic calculation approach will be replaced by a dynamic approach, the numerical models will have to be verified by experimental drop tests.

  8. Simulation and design of multi-stage demineralisation processes by using reverse osmosis and ion exchanger; Simulation und Auslegung mehrstufiger Wasser-Entsalzungsprozesse unter Einsatz von Umkehrosmose und Ionenaustausch

    Energy Technology Data Exchange (ETDEWEB)

    Lipnizki, Jens; Dinges, Bjoern; Schaberger, Heinz [Lanxess Deutschland GmbH, Leverkusen (Germany)

    2013-09-01

    Simulation and design of both reverse osmosis (RO) and ion exchange (IEX) processes for water demineralisation are supported by the user-friendly, integrated software LewaPlus trademark. This new software offers the option to design complex water treatment solutions, and provides the possibility to directly compare the results of RO and IEX calculations. It is possible to calculate with a given water analysis the results of RO treatment, and of subsequent treatment of this water with RO or IEX, respectively. The effect of variables such as temperature, silica, and carbonate concentration in the feed on process design and final water quality can be calculated for a whole system. The paper gives an overview of the capabilities of the software package and presents several application examples. (orig.)

  9. Quality-oriented production of brown-coal coke with due regard to its application in metallurgy and environmental protection; Qualitaetsgerechte Erzeugung von Braunkohlenkoks unter Beruecksichtigung der Anwendung in Metallurgie und Umweltschutz

    Energy Technology Data Exchange (ETDEWEB)

    Achtelik, M.; Erken, M.; Juessen, P.; Knapp, A. [Rheinbraun AG, Koeln (Germany)

    1998-12-31

    In the nineteen seventies the Fortuna Nord refining factory of Rheinbraun AG began to restructure its operations from domestic coal briquetting to the manufacture of industrial products. One of these products, high-temperature brown-coal coke, is produced in two hearth-type furnaces. Coke produced in these plants is mainly used in metallurgy and environmental engineering, in the latter especially for flue gas purification. Rheinbraun has succeeded in introducing a quality management system for brown-coal coke which ensures high quality and security of supply. (orig.) [Deutsch] Im Veredlungsbetrieb Fabrik Fortuna-Nord der Rheinbraun AG begann in den 70er Jahren der Strukturwandel vom Hausbrandbrikett zu Industrieprodukten. Eins dieser Produkte, der Hochtemperatur-Braunkohlenkoks, wird in zwei Herdofenanlagen erzeugt. Die Haupteinsatzbereiche des Herdofenkokses sind die Metallurgie sowie der Umweltschutz und hier insbesondere die Rauchgasreinigung. Um die hohe Produktqualitaet und die Liefersicherheit zu gewaehrleisten, hat Rheinbraun ein Qualitaetsmanagementsystem fuer Braunkohlenkoks erfolgreich eingefuehrt. (orig.)

  10. Nanoscaled boehmites' modes of action in a polymer and its carbon fiber reinforced plastic under compression load; Wirkungsweisen nanoskaliger Boehmite in einem Polymer und seinem Kohlenstofffaserverbund unter Druckbelastung

    Energy Technology Data Exchange (ETDEWEB)

    Arlt, Christine

    2011-07-01

    Increasing ecological awareness as well as quality and safety demands, which are present, for instance, in the aerospace and automotive sectors, lead to the need to use more sophisticated and more effective materials. For that purpose, laminates of carbon fiber reinforced plastic (CFRP), which are manufactured by injection technology, are reinforced with boehmite particles. This doping strengthens the laminates, whose original properties are weaker than prepregs. Besides the shear strength, compression strength and the damage tolerance, the mode of action of the nanoparticles in resin and in CRFP is also analyzed. It thereby reveals that the hydroxyl groups and even more a taurine modification of the boehmites' surface after the elementary polymer morphology. Consequently a new flow and reaction comportment, lower glass transition temperatures and shrinkage, as well as a changed mechanical behavior occur. Due to a structural upgrading of the matrix (higher shear stiffness, reduced residual stress), a better fiber-matrix adhesion, and differing crack paths, the boehmite nanoparticles move the degradation barrier of the material to higher loadings, thus resulting in considerably upgraded new CFRP. (orig.)

  11. Interventional MRI. Current status and potential for development considering economic perspectives. Pt. 2. Liver and other applications in oncology; Interventionelle MRT. Status Quo und Entwicklungspotenzial unter oekonomischen Perspektiven. T. 2. Therapeutische und onkologische Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Barkhausen, Joerg [Univ. Hospital Schleswig Holstein, Luebeck (Germany). Dept. of Radiology and Nuclear Medicine; Kahn, Thomas [Clinic and Policlinic for Diagnostic and Interventional Radiology, Leipzig (Germany); Krombach, Gabriele A. [Univ. Hospital Giessen (Germany). Dept. of Radiology; Kuhl, Christiane K. [Univ. Hospital RWTH Aachen (Germany). Dept. of Diagnostic and Interventional Radiology; Lotz, Joachim [Goettingen Univ. (Germany). Inst. for Diagnostic and Interventional Radiology; Maintz, David [Univ. Hospital Cologne (Germany). Dept. of Radiology; Ricke, Jens [Univ. Hospital Magdeburg (Germany). Dept. of Radiology and Nuclear Medicine; Schoenberg, Stefan O. [Univ. Medical Center Mannheim, Heidelberg Univ., Mannheim (Germany). Inst. of Clinical Radiology and Nuclear Medicine; Vogl, Thomas J. [Frankfurt Univ. Hospital (Germany). Dept. of Diagnostic and Interventional Radiology; Wacker, Frank K. [Hannover Medical School (Germany). Dept. for Diagnostic and Interventional Radiology

    2017-11-15

    MRI is attractive for guiding and monitoring interventional procedures due to its high intrinsic soft tissue contrast and the possibility to measure flow and cardiac function. Technical solutions have been developed for all procedural steps including imaging guidance, MR-safe catheters and instruments and patient monitoring. This has led to widening of the clinical applications. Interventional MRI is becoming increasingly important for the treatment of patients suffering from malignant diseases. The detectability of masses and consequently their accessibility for biopsy is higher, compared to other modalities, due to the high intrinsic soft tissue contrast of MRI. Temperature-dependent sequences allow for minimally invasive and tissue-sparing ablation (A-0 ablation). Interventional MRI has become established in the clinical routine for a variety of indications, including biopsies and tumor ablation. Since the economic requirement of covering costs by reimbursement is met and interventional MRI decreases the mortality and morbidity of interventional procedures, broader application of interventional MRI can be expected in the clinical routine in the future.

  12. Temperature indicating device

    International Nuclear Information System (INIS)

    Angus, J.P.; Salt, D.

    1988-01-01

    A temperature indicating device comprises a plurality of planar elements some undergoing a reversible change in appearance at a given temperature the remainder undergoing an irreversible change in appearance at a given temperature. The device is useful in indicating the temperature which an object has achieved as well as its actual temperature. The reversible change is produced by liquid crystal devices. The irreversible change is produced by an absorbent surface carrying substances e.g. waxes which melt at predetermined temperatures and are absorbed by the surface; alternatively paints may be used. The device is used for monitoring processes of encapsulation of radio active waste. (author)

  13. Numerical investigations of instationary heating processes at motor bearings by means of differently coupled methods of calculation; Numerische Untersuchungen instationaerer Aufheizvorgaenge an einem Motorlager unter Verwendung verschiedener gekoppelter Berechnungsmethoden

    Energy Technology Data Exchange (ETDEWEB)

    Disch, Mario; Wittmeier, Felix; Widdecke, Nils; Wiedemann, Jochen [Forschungsinstitut fuer Fahrzeugmotoren und Kraftfahrwesen (FKFS), Stuttgart (Germany); Reister, Heinrich; Weidmann, Ernst-Peter [Daimler AG, Sindelfingen (Germany)

    2012-11-01

    In the vehicle development process at Daimler, thermal protection is an important task that has to be fulfilled. In the early stages of car development numerical analysis techniques are used to ensure that all critical components stay well below given temperature limits. Especially engine mounts are in the focus of investigation due to the geometrical design and the arrangement next to hot exhaust components. For a better understanding of the complex heat transfer mechanisms taking place in this part and as a first step into transient full Vehicle Thermal Management (VTM) computation, two different transient computational analyses are performed and described in this paper. The first one is the Conjugate Heat Transfer method (CHT) in which convection, conduction and radiation phenomena are solved simultaneously. The second one is a COSIM-method in which fluid and solid structures are splitted into two different simulations and brought to interaction by exchanging data at predetermined points. The major problem in transient computation is that thermal time scales on solid and fluid structures vary over a wide range. Using CHT a fine temporal discretization is needed for fluid and solid computation causing an enormous computational effort. In the COSIM-method solid structures are computed unsteady while the corresponding fluid is treated as steady and recalculated after each exchange. Corresponding measurements at an engine mount test rig show that both transient coupling schemes fit well to unsteady experimental results. In conclusion it can be said that the COSIM-method is an effective alternative to CHT computations for transient thermal applications. Computational and modeling effort can be reduced considerably especially for larger time scales which are relevant for full VTM computations. (orig.)

  14. Temperature fluctuations superimposed on background temperature change

    International Nuclear Information System (INIS)

    Otto, James; Roberts, J.A.

    2016-01-01

    Proxy data allows the temperature of the Earth to be mapped over long periods of time. In this work the temperature fluctuations for over 200 proxy data sets were examined and from this set 50 sets were analyzed to test for periodic and quasi-periodic fluctuations in the data sets. Temperature reconstructions over 4 different time scales were analyzed to see if patterns emerged. Data were put into four time intervals; 4,000 years, 14,000 years, 1,000,000 years, and 3,000,000 years and analyzed with a goal to understanding periodic and quasi-periodic patterns in global temperature change superimposed on a “background” average temperature change. Quasi-periodic signatures were identified that predate the Industrial Revolution, during much of which direct data on temperature are not available. These data indicate that Earth temperatures have undergone a number of periodic and quasi-periodic intervals that contain both global warming and global cooling cycles. The fluctuations are superimposed on a background of temperature change that has a declining slope during the two periods, pre-ice age and post ice age with a transition about 12,000 BCE. The data are divided into “events” that span the time periods 3,000,000 BCE to “0” CE, 1,000,000 BCE to “0” CE, 12,000 BCE to 2,000 CE and 2,000 BCE to 2,000 CE. An equation using a quasi-periodic (frequency modulated sine waves) patterns was developed to analyze the date sets for quasi-periodic patterns. “Periodicities” which show reasonable agreement with the predictions of Milankovitch and other investigators were found in the data sets.

  15. Maine River Temperature Monitoring

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We collect seasonal and annual temperature measurements on an hourly or quarter hourly basis to monitor habitat suitability for ATS and other species. Temperature...

  16. GISS Surface Temperature Analysis

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The GISTEMP dataset is a global 2x2 gridded temperature anomaly dataset. Temperature data is updated around the middle of every month using current data files from...

  17. Supersymmetry at high temperatures

    International Nuclear Information System (INIS)

    Das, A.; Kaku, M.

    1978-01-01

    We investigate the properties of Green's functions in a spontaneously broken supersymmetric model at high temperatures. We show that, even at high temperatures, we do not get restoration of supersymmetry, at least in the one-loop approximation

  18. Supersymmetry at finite temperature

    International Nuclear Information System (INIS)

    Clark, T.E.; Love, S.T.

    1983-01-01

    Finite-temperature supersymmetry (SUSY) is characterized by unbroken Ward identities for SUSY variations of ensemble averages of Klein-operator inserted imaginary time-ordered products of fields. Path-integral representations of these products are defined and the Feynman rules in superspace are given. The finite-temperature no-renormalization theorem is derived. Spontaneously broken SUSY at zero temperature is shown not to be restored at high temperature. (orig.)

  19. Room temperature superconductors

    International Nuclear Information System (INIS)

    Sleight, A.W.

    1995-01-01

    If the Holy Grail of room temperature superconductivity could be achieved, the impact on could be enormous. However, a useful room temperature superconductor for most applications must possess a T c somewhat above room temperature and must be capable of sustaining superconductivity in the presence of magnetic fields while carrying a significant current load. The authors will return to the subject of just what characteristics one might seek for a compound to be a room temperature superconductor. 30 refs., 3 figs., 1 tab

  20. Study of the diffusion of lithium and sodium ions in solids under regardment of the dimensionality of the crystal lattice; Untersuchung der Diffusion von Lithium- und Natrium-Ionen in Festkoerpern unter Beruecksichtigung der Dimensionalitaet des Kristallgitters

    Energy Technology Data Exchange (ETDEWEB)

    Volgmann, Kai Tristan

    2016-07-29

    Low-dimensional diffusion was investigated to improve the understanding of the fundamentals of ion movement in condensed matter. Different model systems with different dimensionality of cation migration pathways were investigated using solidstate nuclear magnetic resonance (NMR) spectroscopy and impedance spectroscopy. Both experimental methods made it possible to complementarily study both Li and Na mobility over a wide range of jump rates. Metallic lithium as a well-known model system for isotropic diffusion was investigated using {sup 7}Li field-cycling NMR. The spin-lattice relaxation (SLR) rates were separated into an electronic contribution and a diffusion-induced contribution. The Korringa product was calculated from the actual measurements. The main focus was the comparison of different theoretical models describing the Li motion in metallic lithium. The well-known model by Bloembergen, Purcell and Pound already reproduced the data well, but two models by Sholl improved the results taking into account the type of crystal lattice and jump correlation effects. A single-vacancy diffusion mechanism was observed, but a double-vacancy mechanism was not excluded as elevated temperatures near the melting point of lithium were not available. Li{sub 0.7}Nb{sub 3}S{sub 4} is isostructural to Li{sub 0.7}Nb{sub 3}Se{sub 4} which was reported as possible 1D Li ion conductor due to its channel structure. Thus, Li{sub 0.7}Nb{sub 3}S{sub 4} was investigated as 1D model system using solid-state NMR spectroscopy. Multinuclear NMR spectroscopy gave insights into structural properties. Li dynamics was observed by several NMR methods over a wide temperature range. {sup 7}Li NMR motional narrowing led to an estimate of the activation energy for local Li hopping. {sup 7}Li NMR spin-alignment echo (SAE) was used for the determination of Li jump rates on a macroscopic scale. Possible dimensionality effects were investigated by {sup 7}Li NMR SLR. Out of the phase system Li{sub 2}O

  1. Simulation of phenomena at crack-like leaks and breaks in piping with consideration of fluid-structure interaction. Final report; Simulation der Phaenomene bei rissartigen Lecks und Bruechen in Rohrleitungen unter Beruecksichtigung der Fluid-Struktur-Kopplung. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Sievers, J.; Grebner, H.; Bahr, L.; Heckmann, K.; Arndt, J.; Pallas-Moner, G.

    2013-11-15

    The evaluation of fluid flow rates through crack-like leaks in pressurized components plays an important role for assessments on break preclusion, especially leak-before-break considerations. In the framework of project RS1194 various calculation methods for the simulation of structure mechanical and thermo-hydraulic phenomena due to flows through crack-like leaks in the coolant circuit were examined and validated on selected leak rate experiments. Besides large program systems as ATHLET, CFX and ADINA also several simplified evaluation methods included in the GRS program WinLeck were applied especially for the determination of leak rates. For the validation of analysing methods, tests were selected previously conducted at the former Nuclear Research Centre (KfK) at Karlsruhe and the Power Plant Union (KWU). The review of experimental results already at disposal in regards to availability of measure d values of thermo-hydraulic parameters like flow-through rates, spatial distributions of pressure, temperature and aggregate state of the medium, velocity of the medium as well as leak openings, displacements and structure strains indicated, that the experiments in terms of quantification of thermo-hydraulic and structure mechanical phenomena as well as appropriate coupling effects do not provide sufficiently meaningful results. Due to missing experiments for validation of 3d numerical flow simulation in crack-like leaks experiments with flow through a Venturi orifice, which are relevant in this context, were chosen. Experiments with single phase flow were considered as well as ones with two phase flow. The post-calculations of the single phase flow showed a good agreement between the calculation results and the appropriate measured data. In the two phase flow, despite tests with various model variations, no satisfying agreement between calculation and test could be reached. According to the authors' opinion is the model approach available in CFX for the

  2. Digital temperature meter

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, S

    1982-01-01

    Digital temperature meter for precise temperature measurements is presented. Its parts such as thermostat, voltage-frequency converter and digital frequency meter are described. Its technical parameters such as temperature range 50degC-700degC, measurement precision 1degC, measurement error +-1degC are given. (A.S.).

  3. Rescaling Temperature and Entropy

    Science.gov (United States)

    Olmsted, John, III

    2010-01-01

    Temperature and entropy traditionally are expressed in units of kelvin and joule/kelvin. These units obscure some important aspects of the natures of these thermodynamic quantities. Defining a rescaled temperature using the Boltzmann constant, T' = k[subscript B]T, expresses temperature in energy units, thereby emphasizing the close relationship…

  4. High-temperature superconductivity

    International Nuclear Information System (INIS)

    Lynn, J.W.

    1990-01-01

    This book discusses development in oxide materials with high superconducting transition temperature. Systems with Tc well above liquid nitrogen temperature are already a reality and higher Tc's are anticipated. The author discusses how the idea of a room-temperature superconductor appears to be a distinctly possible outcome of materials research

  5. Development of an analysis method for determining chlorinated hydrocarbons in marine sediments and suspended matter giving particular consideration to supercritical fluid extraction; Entwicklung eines Analysenverfahrens zur Bestimmung von chlorierten Kohlenwasserstoffen in marinen Sedimenten und Schwebstoffen unter besonderer Beruecksichtigung der ueberkritischen Fluidextraktion

    Energy Technology Data Exchange (ETDEWEB)

    Sterzenbach, D.

    1997-11-01

    diesem Grund soll das gesamte Verfahren und dessen Einzelschritte unter diesem Gesichtspunkt ueberprueft und gegebenenfalls verbessert werden. Fuer die Probennahme von marinen Schwebstoffen soll ein Verfahren erarbeitet werden, das eine effiziente Abtrennung moeglichst kleiner suspendierter Partikel aus Seewasser ermoeglicht. Mit dem entwickelten Analysenverfahren sollen aktuelle Aspekte der Meereschemie zu Quellen, Transport, Verteilung und Verbleib von chlorierten Kohlenwasserstoffen in der marinen Umwelt behandelt werden. (orig.)

  6. In situ measurement of flow characteristics of natural saline rock in loose zones for gas and saline solutions in given rock stress conditions. Final report; In-situ-Ermittlung von Stroemungskennwerten natuerlicher Salzgesteine in Auflockerungszonen gegenueber Gas und Salzloesungen unter den gegebenen Spannungsbedingungen im Gebirge. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Haefner, F.; Belohlavek, K.U.; Behr, A.; Foerster, S.; Pohl, A.

    2001-04-01

    A method and equipment were developed for measuring the extension of loose zones around worked areas in saline rock and for in situ measurement of very small permeabilities and porosities in these zones. The experiments are based on unsteady borehole logs with flowing gases or liquids with special multiple pack systems that enable measurements from 4 cm to 15 m from the cavern contour. The measurements were evaluated by a specially developed software with automatic parameter identification. Permeabilities were identified between 10{sup 14} m{sup 2} and the detection limit of 10{sup 24} m{sup 2} and effective porosities of less than 0.1% at experimental times of several minutes up to several days. The logs were made in 3 mines in Stassfurt rock salt at depths of 700 and 500 m with different geological and geomechanical boundary conditions, worked in different ways and for different periods of time (between a few days and 37 years). Some of the findings were validated by ultrasonic measurements. [German] Fuer die Ermittlung der Ausdehnung von Auflockerungszonen um bergmaennisch aufgefahrene Strecken/Hohlraeume im Salzgestein und zur In-situ-Bestimmung kleinster Permeabilitaeten und Porositaeten in diesen Bereichen wurde ein Verfahren und eine praktikable Versuchsausruestung entwickelt. Diese eignet sich auch fuer Frac-Untersuchungen. Basis der Versuchsdurchfuehrungen sind instationaere Bohrlochuntersuchungen mit Gasen oder Fluessigkeiten als Stroemungsfluid unter Einsatz spezieller Mehrfachpackersysteme. Damit sind Messungen ab 4 cm Abstand zur Hohlraumkontur bis zu 15 m moeglich. Die Versuchsauswertung erfolgt mittels einer speziell entwickelten Software mit automatischer Parameteridentifikation, die die instationaere Stroemung um die Versuchsbohrung raeumlich vollstaendig beschreibt. Permeabilitaeten wurden je nach Abstand zur Hohlraumkontur zwischen 10{sup -14} m{sup 2} und der Nachweisgrenze 10{sup -24} m{sup 2} und effektive Porositaeten bis <0,1% ermittelt, bei

  7. Temperature compensated photovoltaic array

    Science.gov (United States)

    Mosher, Dan Michael

    1997-11-18

    A temperature compensated photovoltaic module (20) comprised of a series of solar cells (22) having a thermally activated switch (24) connected in parallel with several of the cells (22). The photovoltaic module (20) is adapted to charge conventional batteries having a temperature coefficient (TC) differing from the temperature coefficient (TC) of the module (20). The calibration temperatures of the switches (24) are chosen whereby the colder the ambient temperature for the module (20), the more switches that are on and form a closed circuit to short the associated solar cells (22). By shorting some of the solar cells (22) as the ambient temperature decreases, the battery being charged by the module (20) is not excessively overcharged at lower temperatures. PV module (20) is an integrated solution that is reliable and inexpensive.

  8. Locality of Temperature

    Science.gov (United States)

    Kliesch, M.; Gogolin, C.; Kastoryano, M. J.; Riera, A.; Eisert, J.

    2014-07-01

    This work is concerned with thermal quantum states of Hamiltonians on spin- and fermionic-lattice systems with short-range interactions. We provide results leading to a local definition of temperature, thereby extending the notion of "intensivity of temperature" to interacting quantum models. More precisely, we derive a perturbation formula for thermal states. The influence of the perturbation is exactly given in terms of a generalized covariance. For this covariance, we prove exponential clustering of correlations above a universal critical temperature that upper bounds physical critical temperatures such as the Curie temperature. As a corollary, we obtain that above the critical temperature, thermal states are stable against distant Hamiltonian perturbations. Moreover, our results imply that above the critical temperature, local expectation values can be approximated efficiently in the error and the system size.

  9. Melting temperature of graphite

    International Nuclear Information System (INIS)

    Korobenko, V.N.; Savvatimskiy, A.I.

    2001-01-01

    Full Text: Pulse of electrical current is used for fast heating (∼ 1 μs) of metal and graphite specimens placed in dielectric solid media. Specimen consists of two strips (90 μm in thick) placed together with small gap so they form a black body model. Quasy-monocrystal graphite specimens were used for uniform heating of graphite. Temperature measurements were fulfilled with fast pyrometer and with composite 2-strip black body model up to melting temperature. There were fulfilled experiments with zirconium and tungsten of the same black body construction. Additional temperature measurements of liquid zirconium and liquid tungsten are made. Specific heat capacity (c P ) of liquid zirconium and of liquid tungsten has a common feature in c P diminishing just after melting. It reveals c P diminishing after melting in both cases over the narrow temperature range up to usual values known from steady state measurements. Over the next wide temperature range heat capacity for W (up to 5000 K) and Zr (up to 4100 K) show different dependencies of heat capacity on temperature in liquid state. The experiments confirmed a high quality of 2-strip black body model used for graphite temperature measurements. Melting temperature plateau of tungsten (3690 K) was used for pyrometer calibration area for graphite temperature measurement. As a result, a preliminary value of graphite melting temperature of 4800 K was obtained. (author)

  10. Chapter 6: Temperature

    Science.gov (United States)

    Jones, Leslie A.; Muhlfeld, Clint C.; Hauer, F. Richard; F. Richard Hauer,; Lamberti, G.A.

    2017-01-01

    Stream temperature has direct and indirect effects on stream ecology and is critical in determining both abiotic and biotic system responses across a hierarchy of spatial and temporal scales. Temperature variation is primarily driven by solar radiation, while landscape topography, geology, and stream reach scale ecosystem processes contribute to local variability. Spatiotemporal heterogeneity in freshwater ecosystems influences habitat distributions, physiological functions, and phenology of all aquatic organisms. In this chapter we provide an overview of methods for monitoring stream temperature, characterization of thermal profiles, and modeling approaches to stream temperature prediction. Recent advances in temperature monitoring allow for more comprehensive studies of the underlying processes influencing annual variation of temperatures and how thermal variability may impact aquatic organisms at individual, population, and community based scales. Likewise, the development of spatially explicit predictive models provide a framework for simulating natural and anthropogenic effects on thermal regimes which is integral for sustainable management of freshwater systems.

  11. MULTISYS: Computer code for calculating multicomponent equilibria in high-temperature subcritical and supercritical aqueous systems; MULTISYS: Ein Programm zur Berechnung von Mehrkomponenten-Gleichgewichten in unterkritischen und ueberkritischen waessrigen Systemen

    Energy Technology Data Exchange (ETDEWEB)

    Lvov, S.N.; Akinfiev, N.N.; Bandura, A.V.; Sigon, F.; Perboni, G.

    1999-12-01

    The studies of the corrosion and deposition processes on the structural materials of power plants in high temperature aqueous environments have aroused considerable interest. To understand these processes, it is required to develop a detailed knowledge of thermodynamics that control the solution chemistry, phase relations, kinetics, and mass and heat transport. By knowing the equilibrium composition of the high temperature aqueous solution and by accessing the thermodynamic properties of the corrosion products, it is possible to predict the initial stage of the corrosion processes or oxides deposition, in order to protect plant equipment against damages. (orig.) [German] Studien zur Korrosion und zu Ablagerungsprozessen auf den Komponentenwerkstoffen in Kraftwerken in einer waessrigen Hochtemperaturumgebung sind von betraechtlichem Interesse. Um solche Prozesse zu verstehen, muss ein detailliertes Verstaendnis der Thermodynamik vorhanden sein, welches die Loesungschemie, Phasenbeziehungen, Kinetik sowie Masse- und Waermetransport kontrolliert. Mit dem Wissen um die Gleichgewichtszusammensetzung der waessrigen Hochtemperaturloesung und unter Zugriff auf die thermodynamischen Eigenschaften der Korrosionsprodukte ist es moeglich, die einleitende Stufe von Korrosionsprozessen oder Oxidablagerungen vorherzusagen, um so Anlagenkomponenten vor Schaeden zu schuetzen. (orig.)

  12. High temperature refrigerator

    International Nuclear Information System (INIS)

    Steyert, W.A. Jr.

    1978-01-01

    A high temperature magnetic refrigerator is described which uses a Stirling-like cycle in which rotating magnetic working material is heated in zero field and adiabatically magnetized, cooled in high field, then adiabatically demagnetized. During this cycle the working material is in heat exchange with a pumped fluid which absorbs heat from a low temperature heat source and deposits heat in a high temperature reservoir. The magnetic refrigeration cycle operates at an efficiency 70% of Carnot

  13. Temperature control in vacuum

    International Nuclear Information System (INIS)

    Dearnaley, G.

    1986-01-01

    The patent concerns a method for controlling the temperature of silicon wafers (or samples), during ion beam treatment of the wafers, in a vacuum. The apparatus and method are described for irradiation and temperature control of the samples. The wafers are mounted on a drum which is rotated through the ion beam, and are additionally heated by infra-red lamps to achieve the desired temperature. (U.K.)

  14. Low temperature carbonization

    Energy Technology Data Exchange (ETDEWEB)

    Abbott, A A

    1934-01-10

    A process is described in which coal is passed through a distillation chamber in one retort at a comparatively low temperature, then passing the coal through a distillation chamber of a second retort subjected to a higher temperature, thence passing the coal through the distillation chamber of a third retort at a still higher temperature and separately collecting the liquid and vapors produced from each retort.

  15. Temperature measurement and control

    CERN Document Server

    Leigh, JR

    1988-01-01

    This book treats the theory and practice of temperature measurement and control and important related topics such as energy management and air pollution. There are no specific prerequisites for the book although a knowledge of elementary control theory could be useful. The first half of the book is an application oriented survey of temperature measurement techniques and devices. The second half is concerned mainly with temperature control in both simple and complex situations.

  16. Maximal combustion temperature estimation

    International Nuclear Information System (INIS)

    Golodova, E; Shchepakina, E

    2006-01-01

    This work is concerned with the phenomenon of delayed loss of stability and the estimation of the maximal temperature of safe combustion. Using the qualitative theory of singular perturbations and canard techniques we determine the maximal temperature on the trajectories located in the transition region between the slow combustion regime and the explosive one. This approach is used to estimate the maximal temperature of safe combustion in multi-phase combustion models

  17. Neutron ion temperature measurement

    International Nuclear Information System (INIS)

    Strachan, J.D.; Hendel, H.W.; Lovberg, J.; Nieschmidt, E.B.

    1986-11-01

    One important use of fusion product diagnostics is in the determination of the deuterium ion temperature from the magnitude of the 2.5 MeV d(d,n) 3 He neutron emission. The detectors, calibration methods, and limitations of this technique are reviewed here with emphasis on procedures used at PPPL. In most tokamaks, the ion temperature deduced from neutrons is in reasonable agreement with the ion temperature deduced by other techniques

  18. High temperature materials; Materiaux a hautes temperatures

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    The aim of this workshop is to share the needs of high temperature and nuclear fuel materials for future nuclear systems, to take stock of the status of researches in this domain and to propose some cooperation works between the different research organisations. The future nuclear systems are the very high temperature (850 to 1200 deg. C) gas cooled reactors (GCR) and the molten salt reactors (MSR). These systems include not only the reactor but also the fabrication and reprocessing of the spent fuel. This document brings together the transparencies of 13 communications among the 25 given at the workshop: 1) characteristics and needs of future systems: specifications, materials and fuel needs for fast spectrum GCR and very high temperature GCR; 2) high temperature materials out of neutron flux: thermal barriers: materials, resistance, lifetimes; nickel-base metal alloys: status of knowledge, mechanical behaviour, possible applications; corrosion linked with the gas coolant: knowledge and problems to be solved; super-alloys for turbines: alloys for blades and discs; corrosion linked with MSR: knowledge and problems to be solved; 3) materials for reactor core structure: nuclear graphite and carbon; fuel assembly structure materials of the GCR with fast neutron spectrum: status of knowledge and ceramics and cermets needs; silicon carbide as fuel confinement material, study of irradiation induced defects; migration of fission products, I and Cs in SiC; 4) materials for hydrogen production: status of the knowledge and needs for the thermochemical cycle; 5) technologies: GCR components and the associated material needs: compact exchangers, pumps, turbines; MSR components: valves, exchangers, pumps. (J.S.)

  19. Temperature controlled 'void' formation

    International Nuclear Information System (INIS)

    Dasgupta, P.; Sharma, B.D.

    1975-01-01

    The nucleation and growth of voids in structural materials during high temperature deformation or irradiation is essentially dependent upon the existence of 'vacancy supersaturation'. The role of temperature dependent diffusion processes in 'void' formation under varying conditions, and the mechanical property changes associated with this microstructure are briefly reviewed. (author)

  20. Disorders of body temperature.

    Science.gov (United States)

    Gomez, Camilo R

    2014-01-01

    The human body generates heat capable of raising body temperature by approximately 1°C per hour. Normally, this heat is dissipated by means of a thermoregulatory system. Disorders resulting from abnormally high or low body temperature result in neurologic dysfunction and pose a threat to life. In response to thermal stress, maintenance of normal body temperature is primarily maintained by convection and evaporation. Hyperthermia results from abnormal temperature regulation, leading to extremely elevated body temperature while fever results from a normal thermoregulatory mechanism operating at a higher set point. The former leads to specific clinical syndromes with inability of the thermoregulatory mechanism to maintain a constant body temperature. Heat related illness encompasses heat rash, heat cramps, heat exhaustion and heat stroke, in order of severity. In addition, drugs can induce hyperthermia and produce one of several specific clinical syndromes. Hypothermia is the reduction of body temperature to levels below 35°C from environmental exposure, metabolic disorders, or therapeutic intervention. Management of disorders of body temperature should be carried out decisively and expeditiously, in order to avoid secondary neurologic injury. © 2014 Elsevier B.V. All rights reserved.

  1. High temperature structural silicides

    International Nuclear Information System (INIS)

    Petrovic, J.J.

    1997-01-01

    Structural silicides have important high temperature applications in oxidizing and aggressive environments. Most prominent are MoSi 2 -based materials, which are borderline ceramic-intermetallic compounds. MoSi 2 single crystals exhibit macroscopic compressive ductility at temperatures below room temperature in some orientations. Polycrystalline MoSi 2 possesses elevated temperature creep behavior which is highly sensitive to grain size. MoSi 2 -Si 3 N 4 composites show an important combination of oxidation resistance, creep resistance, and low temperature fracture toughness. Current potential applications of MoSi 2 -based materials include furnace heating elements, molten metal lances, industrial gas burners, aerospace turbine engine components, diesel engine glow plugs, and materials for glass processing

  2. Stable and flexible under power; Stabil und flexibel unter Strom

    Energy Technology Data Exchange (ETDEWEB)

    Irrgang, Reinhard

    2011-03-25

    If conveyor routes, shelve service devices, hall cranes or other haulage equipment - all this systems want to be supported economically, securely and reliably by energy. Optimized energy chains and gliding connect with innovative details function as probate systems. Also touchless energy- and data transmission technologies open an immense potential. (orig./GL)

  3. Vehicles under electricity. Result booklet; Autos unter Strom. Ergebnisbroschuere

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-09-15

    The booklet under consideration reports on the environmental relief of electric-driven vehicles by means of the research project OPTUM 'Potentials of environmental relief of electric driven vehicles - Integrated analysis of vehicle usage and energy economy'. Experts from the Institute for Applied Ecology (Freiburg, Federal Republic of Germany) and the Institute for Social-Ecological Research (Frankfurt (Main), Federal Republic of Germany) are devoted to the following issues: (1) What is the acceptance for electric-driven vehicles?; (2) What is their future market potential?; (3) What are the advantages of electromobility with respect to the climate?; (4) Are their supply shortages concerning major raw materials?.

  4. Der antiskeptische Boden unter dem Gehirn im Tank

    OpenAIRE

    Müller, Olaf L.

    2001-01-01

    Crispin Wright hat die bislang beste Rekonstruktion von Putnams Beweis gegen die skeptische Hypothese vom Gehirn im Tank vorgelegt. Aber selbst in Wrights Fassung hat der Beweis einen Mangel: Er wird mithilfe eines Prädikates wie z.B. "Tiger" geführt und funktioniert nur, wenn man sich darauf verlassen kann, dass es Tiger wirklich gibt. Aber die Skeptikerin bestreitet, über die Existenz von Tigern bescheid zu wissen. Das Problem lässt sich dadurch beheben, dass man den Beweis – statt mit dem ...

  5. Electricity trade under financial market supervision; Der Stromhandel unter Finanzmarktaufsicht

    Energy Technology Data Exchange (ETDEWEB)

    Hagena, Martin

    2011-07-01

    With the competitive opening of the electricity market at European and national level, the goods electricity became a freely traded commodity. The author of the contribution under consideration describes the legal consequences related to financial market for trading electricity in the context of the current Directive 2004/39/EC now under consideration of the commodity futures trading in its representational scope. The statements clearly indicate that the power market is a goods market with its own laws and not a classical financial market. It considers what characteristics exist in electricity trading and whether and how they are considered for regulatory purposes.

  6. Mythos Qualifikation – Berufungsverfahren unter der gleichstellungspolitischen Lupe

    Directory of Open Access Journals (Sweden)

    Eva Blome

    2008-11-01

    Full Text Available Auf der Grundlage von qualitativen Interviews und einer Vollerhebung aller Verfahrensregelungen liefert die Studie eine umfassende Analyse der Gestaltung von Berufungsverfahren aus gleichstellungspolitischer Perspektive. Aufgrund der ergänzenden konkreten Handlungsempfehlungen zum gleichstellungsorientierten Verfahrensmanagement verhilft die Untersuchung nicht nur zu einer empirisch fundierten Einsicht in die Diskriminierungsmechanismen an deutschen Hochschulen, sondern stellt zudem einen wichtigen Beitrag für die Integration von Gleichstellung in die aktuellen Reformen von Berufungsverfahren dar.

  7. Akustische und perzeptive Analysen von Sprache unter Alkoholeinfluss

    OpenAIRE

    Baumeister, Barbara Susanne

    2015-01-01

    In this thesis, several acoustic and perceptive studies on the influence of alcoholic intoxication on speech are presented. The speech samples for the experiments are taken from the Alcohol Language Corpus, a large database containing recordings of 162 (77 female and 85 male) speakers in both sober and intoxicated conditions with various blood alcohol concentrations. An acoustic analysis of recordings of 148 speakers in intoxicated and sober condition reveals a significant increase of the mea...

  8. Control of supply temperature

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, H; Nielsen, T S; Soegaard, H T

    1996-09-01

    For many district heating systems, e.g. the system in Hoeje Taastrup, it is desirable to minimize the supply temperature from the heat production unit(s). Lower supply temperature implies lower costs in connection with the production and distribution of heat. Factors having impact on the heat demand are for instance solar radiation, wind speed, wind direction and a climate independent part, which is a function of the time of the day/week/year. By applying an optimization strategy, which minimizes the supply temperature, it is assumed that optimal economical operation can be obtained by minimizing the supply temperature and thereby the heat losses in the system. The models and methods described in this report take such aspects into account, and can therefore be used as elements in a more efficient minimization of the supply temperature. The theoretical part of this report describes models and methods for optimal on-line control of the supply temperature in district heating systems. Some of the models and methods have been implemented - or are going to be implemented - in the computer program PRESS which is a tool for optimal control of supply temperature and forecasting of heat demand in district heating systems. The principles for using transfer function models are briefly described. The ordinary generalized predictive control (OGPC) method is reviewed, and several extensions of this method are suggested. New controller, which is called the extended generalized predictive controller (XGPC), is described. (EG) 57 refs.

  9. Visualisation of flux distributions in high-temperature superconductors. Final report; Sichtbarmachung der Flussverteilung in Hochtemperatursupraleitern nach verschiedenen Mikrostrukturaenderungen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, H.; Kronmueller, H.

    1998-05-01

    Theoretical calculation models for current, magnetic and electric field distributions in thin superconductors of arbitrary shape in perpendicular magnetic field were developed. Calculations were done for inhomogeneous and anisotropic critical currents and compared with magnetooptical observations of flux penetration. Nice agreement of theory and experiment was found. Flux-line depinning and motion in superconductors with linear defects was investigated by magneto-optics. Depinning mechanisms were deduced from observations of high-temperature superconductors which are irradiated with swift heavy ions parallel and crosswisely at various angles to the surface normal. Magneto-optical investigations of flux penetration into (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+{delta}} multifilament tapes showed a strong dependence of the current capability on the microstructure of single filaments. The different filament textures which are caused by the inhomogeneous deformation of the tape during thermomechanical treatment results in critical current densities varying by about one order of magnitude. (orig.) [Deutsch] Theoretische Modelle zur Berechnung von Strom-, Magnet- und elektrischen Feldverteilungen wurden fuer duenne Supraleiter beliebiger Geometrie mit inhomogener und anisotroper kritischer Stromdichte im senkrechten Magnetfeld entwickelt und mit magnetooptischen Beobachtungen des Flusseindringens verglichen, wobei eine hervorragende Uebereinstimmung zwischen Theorie und Experiment erzielt wurde. Mit Hilfe von magnetooptischen Untersuchungen des Flusseindringens in schwerionenbestrahlte Hochtemperatursupraleiter, die unter verschiedenen Winkeln zur Oberflaechennormalen parallel und kreuzweise bestrahlt wurden, konnten Bewegungs- und Entankerungsmechanismen von Flusslinien in Supraleitern mit linearen Defekten abgeleitet werden. Magnetooptische Untersuchungen des Flusseindringens in (Bi, Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+{delta

  10. High temperature pipeline design

    Energy Technology Data Exchange (ETDEWEB)

    Greenslade, J.G. [Colt Engineering, Calgary, AB (Canada). Pipelines Dept.; Nixon, J.F. [Nixon Geotech Ltd., Calgary, AB (Canada); Dyck, D.W. [Stress Tech Engineering Inc., Calgary, AB (Canada)

    2004-07-01

    It is impractical to transport bitumen and heavy oil by pipelines at ambient temperature unless diluents are added to reduce the viscosity. A diluted bitumen pipeline is commonly referred to as a dilbit pipeline. The diluent routinely used is natural gas condensate. Since natural gas condensate is limited in supply, it must be recovered and reused at high cost. This paper presented an alternative to the use of diluent to reduce the viscosity of heavy oil or bitumen. The following two basic design issues for a hot bitumen (hotbit) pipeline were presented: (1) modelling the restart problem, and, (2) establishing the maximum practical operating temperature. The transient behaviour during restart of a high temperature pipeline carrying viscous fluids was modelled using the concept of flow capacity. Although the design conditions were hypothetical, they could be encountered in the Athabasca oilsands. It was shown that environmental disturbances occur when the fluid is cooled during shut down because the ground temperature near the pipeline rises. This can change growing conditions, even near deeply buried insulated pipelines. Axial thermal loads also constrain the design and operation of a buried pipeline as higher operating temperatures are considered. As such, strain based design provides the opportunity to design for higher operating temperature than allowable stress based design methods. Expansion loops can partially relieve the thermal stress at a given temperature. As the design temperature increase, there is a point at which above grade pipelines become attractive options, although the materials and welding procedures must be suitable for low temperature service. 3 refs., 1 tab., 10 figs.

  11. Temperature measurement device

    International Nuclear Information System (INIS)

    Oltman, B.G.; Eckerman, K.F.; Romberg, G.P.; Prepejchal, W.

    1975-01-01

    Thermoluminescent dosimeter (TLD) material is exposed to a known amount of radiation and then exposed to the environment where temperature measurements are to be taken. After a predetermined time period, the TLD material is read in a known manner to determine the amount of radiation energy remaining in the TLD material. The difference between the energy originally stored by irradiation and that remaining after exposure to the temperature ofthe environment is a measure of the average temperature of the environment during the exposure. (U.S.)

  12. Finite temperature field theory

    CERN Document Server

    Das, Ashok

    1997-01-01

    This book discusses all three formalisms used in the study of finite temperature field theory, namely the imaginary time formalism, the closed time formalism and thermofield dynamics. Applications of the formalisms are worked out in detail. Gauge field theories and symmetry restoration at finite temperature are among the practical examples discussed in depth. The question of gauge dependence of the effective potential and the Nielsen identities are explained. The nonrestoration of some symmetries at high temperature (such as supersymmetry) and theories on nonsimply connected space-times are al

  13. High temperature reaction kinetics

    International Nuclear Information System (INIS)

    Jonah, C.D.; Beno, M.F.; Mulac, W.A.; Bartels, D.

    1985-01-01

    During the last year the dependence of the apparent rate of OD + CO on water pressure was measured at 305, 570, 865 and 1223 K. An explanation was found and tested for the H 2 O dependence of the apparent rate of OH(OD) + CO at high temperatures. The isotope effect for OH(D) with CO was determined over the temperature range 330 K to 1225 K. The reason for the water dependence of the rate of OH(OD) + CO near room temperatures has been investigated but no clear explanation has been found. 1 figure

  14. Microelectronic temperature sensor; silicon temperature sensor

    International Nuclear Information System (INIS)

    Beitner, M.; Kanert, W.; Reichert, H.

    1982-01-01

    The goal of this work was to develop a silicon temperature sensor with a sensitivity and a reliability as high and a tolerance as small as possible, for use in measurement and control. By employing the principle of spreading-resistance, using silicon doped by neutron transmutation, and trimming of the single wafer tolerances of resistance less than +- 5% can be obtained; overstress tests yielded a long-term stability better than 0.2%. Some applications show the advantageous use of this sensor. (orig.) [de

  15. Development of an ultratrace analysis method for elements of the platinum group contained in environmental and geological samples using an ICP-QMS with isotope dilution analysis and suitable separation techniques; Entwicklung eines Verfahrens zur Ultraspurenbestimmung der Platingruppenelemente in Umwelt- und geologischen Proben mit einem ICP-QMS unter Verwendung der Isotopenverduennungsanalyse sowie geeigneter Separationstechniken

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, M.

    2001-07-01

    environment of elements of the platinum group. [German] Schwerpunkt dieser Arbeit war die Verfahrensentwicklung zur Ultraspurenbestimmung der PGE in Umwelt- und geologischen Proben unter Verwendung der massenspektrometrischen Isotopenverduennungsanalyse mit anschliessender Bestimmung an einem Quadrupol ICP-MS (ICP-QMSIVA). Das in dieser Arbeit entwickelte Verfahren zur Ultraspurenbestimmung der PGE mit ICPQMSIVA wurde im Rahmen des Projektes ''Production and certification of a road dust reference material for platinum, palladium and rhodium (PGEs) in automative catalytic converters (PACEPAC)'' der Europaeischen Union zur Zertifizierung von zwei Referenzmaterialien fuer Umweltproben eingesetzt. Hierbei wurde in der Vorrunde der Zertifizierung (''intercomparison round'') eine sehr gute Uebereinstimmung der Ergebnisse mit dem gewichteten Mittelwert der Ergebnisse fuer Pd und Pt mit den uebrigen teilnehmenden Laboratorien festgestellt. Die mit der hier entwickelten Methode erhaltenen Ergebnisse wurden ohne Ausnahme fuer alle gemessenen Elemente zur vorlaeufigen Zertifizierung herangezogen. Damit leistete die vorliegende Arbeit einen erheblichen Beitrag zum erfolgreichen Abschluss dieses Projekts. Den Erwartungen hinsichtlich Richtigkeit und Reproduzierbarkeit des entwickelten Verfahrens wurde somit voll entsprochen. Erneut konnte die grosse Bedeutung der Isotopenverduennungstechnik fuer die Zertifizierung von Referenzmaterialien aufgezeigt werden, da mit dieser Technik bei sachgerechtem Einsatz Ergebnisse hoher Richtigkeit erzielt werden. Durch vergleichende Messungen mit der NiS-Dokimasie und NAA, die in einer Kooperation mit dem Kernchemischen Institut der Universitaet Mainz durchgefuehrt wurden, und dem hier verwendeten Verfahren, konnten uebereinstimmende Daten, hinsichtlich der Abnahme der Konzentrationen von Pd und Pt in Abhaengigkeit von der Entfernung zu einer Autobahn, erzielt werden. Diese Arbeit und die Forschungsergebnisse, die

  16. Temperatures of exploding nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Serfling, V.; Schwarz, C.; Begemann-Blaich, M.; Fritz, S.; Gross, C.; Kleinevoss, U.; Kunze, W.D; Lynen, U.; Mahi, M.; Mueller, W.F.J.; Odeh, T.; Schnittker, M.; Trautmann, W.; Woerner, A.; Xi, H. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Bassini, R.; Iori, I.; Moroni, A.; Petruzzelli, F. [Milan Univ. (Italy). Ist. di Scienze Fisiche]|[Istituto Nazionale di Fisica Nucleare, Milan (Italy); Gaff, S.J.; Kunde, G.J. [Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy]|[Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab.; Imme, G.; Maddalena, V.; Nociforo, C.; Raciti, G.; Riccobene, G.; Romano, F.P.; Saija, A.; Sfienti, C.; Verde, G. [Catania Univ. (Italy). Dipt. di Fisica]|[Istituto Nazionale di Fisica Nucleare, Catania (Italy); Moehlenkamp, T.; Seidel, W. [Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany); Ocker, B.; Schuettauf, A. [Frankfurt Univ. (Germany). Inst. fuer Kernphysik; Pochodzalla, J. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Trzcinski, A.; Zwieglinski, B. [Soltan Inst. for Nuclear Studies, Warsaw (Poland)

    1998-01-01

    Breakup temperatures in central collisions of {sup 197}Au+{sup 197}Au at bombarding energies E/A=50 to 200 MeV were determined with two methods. Isotope temperatures, deduced from double ratios of hydrogen, helium, and lithium isotopic yields, increase monotonically with bombarding energy from 5 MeV to 12 MeV, in qualitative agreement with a scenario of chemical freeze-out after adiabatic expansion. Excited-state temperatures, derived from yield ratios of states in {sup 4}He, {sup 5,6}Li, and {sup 8}Be, are about 5 MeV, independent of the projectile energy, and seem to reflect the internal temperature of fragments at their final separation from the system. (orig.)

  17. Surface Temperature Data Analysis

    Science.gov (United States)

    Hansen, James; Ruedy, Reto

    2012-01-01

    Small global mean temperature changes may have significant to disastrous consequences for the Earth's climate if they persist for an extended period. Obtaining global means from local weather reports is hampered by the uneven spatial distribution of the reliably reporting weather stations. Methods had to be developed that minimize as far as possible the impact of that situation. This software is a method of combining temperature data of individual stations to obtain a global mean trend, overcoming/estimating the uncertainty introduced by the spatial and temporal gaps in the available data. Useful estimates were obtained by the introduction of a special grid, subdividing the Earth's surface into 8,000 equal-area boxes, using the existing data to create virtual stations at the center of each of these boxes, and combining temperature anomalies (after assessing the radius of high correlation) rather than temperatures.

  18. Temperature measurement device

    International Nuclear Information System (INIS)

    Fournier, Christian; Lions, Noel.

    1975-01-01

    The present invention relates to a temperature measuring system that can be applied in particular to monitoring the temperature of the cooling liquid metal of the outlet of the core assemblies of a fast reactor. Said device combines a long hollow metallic pole, at least partially dipped into the liquid metal and constituting a first thermocouple junction between said pole, and two metallic conductors of different nature, joined at one of their ends to constitute the second thermocouple junction. Said conductors suitably insulated are arranged inside a sheath. Said sheath made of the same metals as the pole extends inside the latter and is connected with the pole through a soldered joint. Said reliable system permits an instantaneous measurement of a quantity representing the variations in the recorded temperature and a measurement of the mean surrounding temperature that can be direcly used as a reference for calibrating the first one [fr

  19. Designing for elevated temperature

    International Nuclear Information System (INIS)

    Boer, G.A. de

    1982-01-01

    The reasons for the application of higher process temperatures are explained. The properties of stainless steel are compared with those of other materials such as molybdenum. Factors influencing the choice of the material such as availability of material data at high temperature, controllability, and strength of heat-affected zone are discussed. The process of designing a structure for safe and economic high-temperature application is outlined: design-by-analysis in contrast to the design-by-rule which is general practice for low-temperature applications. The rules laid down in the ASME Pressure Vessel Code Case N47 are explained as well as the procedure for inelastic stress calculations. (author)

  20. Elevated temperature fracture mechanics

    International Nuclear Information System (INIS)

    Tomkins, B.

    1979-01-01

    The application of fracture mechanics concepts to cracks at elevated temperatures is examined. Particular consideration is given to the characterisation of crack tip stress-strain fields and parameters controlling crack extension under static and cyclic loads. (author)

  1. High temperature battery. Hochtemperaturbatterie

    Energy Technology Data Exchange (ETDEWEB)

    Bulling, M.

    1992-06-04

    To prevent heat losses of a high temperature battery, it is proposed to make the incoming current leads in the area of their penetration through the double-walled insulating housing as thermal throttle, particularly spiral ones.

  2. QCD at finite temperature

    International Nuclear Information System (INIS)

    Kikkawa, Keiji

    1983-01-01

    The varidity of the perturbation method in the high temperature QCD is discussed. The skeleton expansion method takes account of plasmon effects and eliminates the electric infrared singularity but not the magnetic one. A possibility of eliminating the latter, which was recently proposed, is examined by a gauge invariant skeleton expansion. The magnetic singularity is unable to be eliminated by the perturbation method. This implies that some non-perturbative approaches must be incorporated in the high temperature QCD. (author)

  3. High-temperature superconductivity

    International Nuclear Information System (INIS)

    Ginzburg, V.L.

    1987-07-01

    After a short account of the history of experimental studies on superconductivity, the microscopic theory of superconductivity, the calculation of the control temperature and its possible maximum value are presented. An explanation of the mechanism of superconductivity in recently discovered superconducting metal oxide ceramics and the perspectives for the realization of new high-temperature superconducting materials are discussed. 56 refs, 2 figs, 3 tabs

  4. Temperature measuring device

    Energy Technology Data Exchange (ETDEWEB)

    Lauf, R.J.; Bible, D.W.; Sohns, C.W.

    1999-10-19

    Systems and methods are described for a wireless instrumented silicon wafer that can measure temperatures at various points and transmit those temperature readings to an external receiver. The device has particular utility in the processing of semiconductor wafers, where it can be used to map thermal uniformity on hot plates, cold plates, spin bowl chucks, etc. without the inconvenience of wires or the inevitable thermal perturbations attendant with them.

  5. Sweating at low temperature

    International Nuclear Information System (INIS)

    Chalaye, H.; Launay, J.P.

    1980-11-01

    Tests of penetration liquids normally used between 10 and 40 0 C have shown that the arrangement of operationaal conditions (penetration and revealing times) was not sufficient to maintain their sensitivity below 10 0 C, thereby confirming that this temperature is a limit below which such products cannot be employed. The results achieved with a penetrant and a tracer specially devised for low temperatures (SHERWIN B 305 + D100) are satisfactory between 0 0 C and 15 0 C [fr

  6. Temperature in the throat

    Directory of Open Access Journals (Sweden)

    Dariush Kaviani

    2016-09-01

    Full Text Available We study the temperature of extended objects in string theory. Rotating probe D-branes admit horizons and temperatures a la Unruh effect. We find that the induced metrics on slow rotating probe D1-branes in holographic string solutions including warped Calabi–Yau throats have distinct thermal horizons with characteristic Hawking temperatures even if there is no black hole in the bulk Calabi–Yau. Taking the UV/IR limits of the solution, we show that the world volume black hole nucleation depends on the deformation and the warping of the throat. We find that world volume horizons and temperatures of expected features form not in the regular confining IR region but in the singular nonconfining UV solution. In the conformal limit of the UV, we find horizons and temperatures similar to those on rotating probes in the AdS throat found in the literature. In this case, we also find that activating a background gauge field form the U(1 R-symmetry modifies the induced metric with its temperature describing two different classes of black hole solutions.

  7. Development of CaO-swelling cements for cementing of natural gas underground storage wells in field trial (temperature range {<=} 60 C) and composition of CaO and MgO-swelling cements for a temperature range between 60 C-105 C. Final report; Entwicklung von CaO-Quellzementen fuer die Zementation von Erdgasspeicherbohrungen im Feldversuch (Temperaturbereich {<=} 60 C) sowie Formulierung von CaO- und MgO-Quellzementen fuer den Einsatz im Temperaturbereich 60 C-105 C. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Ghofrani, R.; Gheorghiu, A.S.; Radu, G.; Rogojinoiu, E.; Stan, M.; Miehe, H.

    2000-11-01

    The investigations conducted within the scope of this project are a consistent continuation of the work already performed at ITE, especially DGMK research projects 444-1, 444-2 and 444-3. These investigations should lead to a field trial of selected CaO-swelling cement recipes. Essential parameters examined within the course of this project include the HPHT-consistency behavior, HPHT-expansion behavior and the long-term stability behavior of CaO-swelling cements under similar conditions to those prevailing in the borehole. The swelling cement will be made up in correlation with the appropriate industrial make up method using the ITE-equipment; in accordance to the borehole conditions, the swelling cement slurry will be then treated in the ITE-Circulating Facility with respect to shear, temperature and pressure. The cement slurry treated in the ITE-Circulating Facility in accordance to the borehole conditions will be then experimentally investigated regarding the HPHT-consistency behavior and HPHT-expansion behavior. With respect to the long-term stability the swelling cement slurry treated in the Circulating Facility will be cured in autoclaves under appropriate pT-conditions. After evacuation from the autoclaves the compressive strength, the shear strength and the system permeability of the samples will be measured. With respect to the properties of a CaO-reference swelling cement recipe measured under the same experimental conditions, the ITE-make up method has been correlated to the common industrial make up methods LPHM, LPRM and HPRM; the alignment of the ITE-make up method with the planned industrial make up method for an appropriate cement job should make sure that the properties of a swelling cement measured in lab will be of practice relevance. For filling in and annular cementing of selected boreholes CaO-swelling cement recipes have been composed, optimized after experimental investigation results, and ultimately released to field usage after the results

  8. Temperature Effect on Energy Demand

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Duk [Korea Energy Economics Institute, Euiwang (Korea)

    1999-03-01

    We provide various estimates of temperature effect for accommodating seasonality in energy demand, particularly natural gas demand. We exploit temperature response and monthly temperature distribution to estimate the temperature effect on natural gas demand. Both local and global smoothed temperature responses are estimated from empirical relationship between hourly temperature and hourly energy consumption data during the sample period (1990 - 1996). Monthly temperature distribution estimates are obtained by kernel density estimation from temperature dispersion within a month. We integrate temperature response and monthly temperature density over all the temperatures in the sample period to estimate temperature effect on energy demand. Then, estimates of temperature effect are compared between global and local smoothing methods. (author). 15 refs., 14 figs., 2 tabs.

  9. Low temperature distillation

    Energy Technology Data Exchange (ETDEWEB)

    Vandegrift, J N; Postel, C

    1929-04-09

    To recover gas, oil tars, and coked residues by low temperature distillation from bituminous coals, lignites, oil shales, and the like, the raw material is fed from a hopper into a rotary retort which is zonally heated, the temperature being greatest at the discharge end. The material is heated first to a relatively low temperature, thereby removing the moisture and lighter volatiles which are withdrawn through a pipe by the suction of a pump, while the higher boiling point volatiles and fixed gases are withdrawn by suction through an outlet from the higher temperature zone. The vapors withdrawn from the opposite ends of the retort pass through separate vapor lines and condensers, and the suction in each end of the retort, caused by the pumps, is controlled by valves, which also control the location of the neutral point in the retort formed by said suction. Air and inert gas may be introduced into the retort from pipe and stack respectively through a pipe, and steam may be admitted into the high temperature zone through a pipe.

  10. High temperature thermometric phosphors

    Science.gov (United States)

    Allison, Stephen W.; Cates, Michael R.; Boatner, Lynn A.; Gillies, George T.

    1999-03-23

    A high temperature phosphor consists essentially of a material having the general formula LuPO.sub.4 :Dy.sub.(x),Eu.sub.y) wherein: 0.1 wt %.ltoreq.x.ltoreq.20 wt % and 0.1 wt %.ltoreq.y.ltoreq.20 wt %. The high temperature phosphor is in contact with an article whose temperature is to be determined. The article having the phosphor in contact with it is placed in the environment for which the temperature of the article is to be determined. The phosphor is excited by a laser causing the phosphor to fluoresce. The emission from the phosphor is optically focused into a beam-splitting mirror which separates the emission into two separate emissions, the emission caused by the dysprosium dopant and the emission caused by the europium dopent. The separated emissions are optically filtered and the intensities of the emission are detected and measured. The ratio of the intensity of each emission is determined and the temperature of the article is calculated from the ratio of the intensities of the separate emissions.

  11. Temperature Data Evaluation

    International Nuclear Information System (INIS)

    Gillespie, David

    2003-01-01

    Groundwater temperature is sensitive to the competing processes of heat flow from below the advective transport of heat by groundwater flow. Because groundwater temperature is sensitive to conductive and advective processes, groundwater temperature may be utilized as a tracer to further constrain the uncertainty of predictions of advective radionuclide transport models constructed for the Nevada Test Site (NTS). Since heat transport, geochemical, and hydrologic models for a given area must all be consistent, uncertainty can be reduced by devaluing the weight of those models that do not match estimated heat flow. The objective of this study was to identify the quantity and quality of available heat flow data at the NTS. One-hundred-forty-five temperature logs from 63 boreholes were examined. Thirteen were found to have temperature profiles suitable for the determination of heat flow values from one or more intervals within the boreholes. If sufficient spatially distributed heat flow values are obtained, a heat transport model coupled to a hydrologic model may be used to reduce the uncertainty of a nonisothermal hydrologic model of the NTS

  12. Do `negative' temperatures exist?

    Science.gov (United States)

    Lavenda, B. H.

    1999-06-01

    A modification of the second law is required for a system with a bounded density of states and not the introduction of a `negative' temperature scale. The ascending and descending branches of the entropy versus energy curve describe particle and hole states, having thermal equations of state that are given by the Fermi and logistic distributions, respectively. Conservation of energy requires isentropic states to be isothermal. The effect of adiabatically reversing the field is entirely mechanical because the only difference between the two states is their energies. The laws of large and small numbers, leading to the normal and Poisson approximations, characterize statistically the states of infinite and zero temperatures, respectively. Since the heat capacity also vanishes in the state of maximum disorder, the third law can be generalized in systems with a bounded density of states: the entropy tends to a constant as the temperature tends to either zero or infinity.

  13. Estimating plasma temperatures

    International Nuclear Information System (INIS)

    Nash, J.K.; Iglesias, C.A.; Chen, M.H.; Rogers, F.J.

    1992-04-01

    Recent laser-produced plasma experiments have relied on spectroscopic comparisons with models to infer plasma temperatures. The models use an experimentally determined value for the matter density as input and treat the temperature as a free parameter to obtain a best fit to the experimental absorption spectrum. However, uncertainties in the ionization balance theories lead to inferred temperatures that are model dependent. We report results of a new approach which combines high=quality atomic data with an ionization balance obtained from systematic expansions of the grand canonical ensemble. The latter avoids the ad hoc cutoffs required in free energy minimization schemes and includes Coulomb corrections usually neglected in other models. Comparisons to experimental spectra show excellent agreement

  14. Temperature-reflection I

    DEFF Research Database (Denmark)

    McGady, David A.

    2017-01-01

    -temperature path integrals for quantum field theories (QFTs) should be T-reflection invariant. Because multi-particle partition functions are equal to Euclidean path integrals for QFTs, we expect them to be T-reflection invariant. Single-particle partition functions though are often not invariant under T......In this paper, we revisit the claim that many partition functions are invariant under reflecting temperatures to negative values (T-reflection). The goal of this paper is to demarcate which partition functions should be invariant under T-reflection, and why. Our main claim is that finite...... that T-reflection is unrelated to time-reversal. Finally, we study the interplay between T-reflection and perturbation theory in the anharmonic harmonic oscillator in quantum mechanics and in Yang-Mills in four-dimensions. This is the first in a series of papers on temperature-reflections....

  15. The behaviour of concrete at high temperatures and triaxial stress - FE model based on the concrete structure; Betonverhalten bei hohen Temperaturen und triaxialer Beanspruchung - FE-Modell auf der Basis der Betonstruktur

    Energy Technology Data Exchange (ETDEWEB)

    Ameler, J.

    1997-12-31

    In this work, an analytical material model was developed, based on the finite element (FE) method, with which the material behaviour of a normal quartzite concrete under temperature stress can be described. Starting from natural fires, the short term area and temperatures between the normal temperature and about 800 C are of special interest. Altogether, it was found that important processes reducing the strength, which occur in high temperature stresses of concrete, can be directly traced back to the additive or the mortar phase, while others are due to the interaction between the two partners. In this attempted model, the compound material concrete is therefore regarded as a system consisting of two components, the additive and the mortar matrix. The mortar matrix is defined as the part consisting of the cement, the water and the fine proportion of the additive (diameter{<=}4 mm). (orig./MM) [Deutsch] In der vorliegenden Arbeit wurde ein analytisches Werkstoffmodell auf der Basis der FE-Methode entwickelt, mit dem das Werkstoffverhalten eines quarzitischen Normalbetons unter einer Temperaturbeanspruchung beschrieben werden kann. Ausgehend vom natuerlichen Brandgeschehen, interessieren besonders der Kurzzeitbereich und Temperaturen zwischen Normaltemperatur und ca. 800 C. In der Summe zeichnet sich ab, dass wesentliche festigkeitsmindernde Prozesse, die sich bei einer Hochtemperaturbeanspruchung von Beton abspielen, direkt dem Zuschlag bzw. der Moertelphase zugeordnet werden koennen, waehrend andere auf die Interaktion zwischen den beiden Partnern zurueckzufuehren sind. Im vorliegenden Modellansatz wird der Verbundwerkstoff Beton deshalb als ein aus zwei Komponenten bestehendes System betrachtet, dem Zuschlag und der Moertelmatrix. Die Moertelmatrix wird als der aus dem Zement, dem Wasser und dem Feinanteil des Zuschlags (Durchmesser{<=}4 mm) zusammengesetzte Teil definiert. (orig./MM)

  16. ITS Temperature Monitoring

    CERN Document Server

    Savin, A E; CERN. Geneva; Gerasimov, S F

    1999-01-01

    The results of the R&D done under the ISTC#345 grant are presented for consideration for possible future application. The choice of the temperature sensors is described. Thin-film miniature Pt-sensors were produced and the results of the metrological studies of the manufactured samples are presented. The multi-channel temperature data readout system prototype and results of long-term stability tests are discussed. List of figures: Figure 1 Thin film Pt-thermometer topology Figure 2 Studies of long-term stability of Pt-thermometers Figure 3 DT structural scheme Figures 4 & 5 Output data ADC read operation, Control register ADC write operation

  17. Low temperature destructive distillation

    Energy Technology Data Exchange (ETDEWEB)

    1938-07-05

    A process is given and apparatus is described for the destructive distillation at low temperature of coal, oil shale, and the like by subjection to the action of a stream of hot gases or superhearted steam, flowing in a closed circuit. Subsequent treatment of the distillation residues with a gas stream containing oxygen results in combustion of the carbon-containing material therein brings to a high temperature the solid residue, in which the process comprises subsequently contacting the hot solid residue with the fluid stream effecting the distillation.

  18. WORKSHOP: Low temperature devices

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    With extraterrestrial neutrinos (whether from the sun or further afield) continuing to make science news, and with the search for the so far invisible 'dark matter' of the universe a continual preoccupation, physicists from different walks of life (solid state, low temperature, particles, astrophysics) gathered at a workshop on low temperature devices for the detection of neutrinos and dark matter, held from 12-13 March at Ringberg Castle on Lake Tegernsee in the Bavarian Alps, and organized by the Max Planck Institute for Physics and Astrophysics in Munich

  19. WORKSHOP: Low temperature devices

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1987-06-15

    With extraterrestrial neutrinos (whether from the sun or further afield) continuing to make science news, and with the search for the so far invisible 'dark matter' of the universe a continual preoccupation, physicists from different walks of life (solid state, low temperature, particles, astrophysics) gathered at a workshop on low temperature devices for the detection of neutrinos and dark matter, held from 12-13 March at Ringberg Castle on Lake Tegernsee in the Bavarian Alps, and organized by the Max Planck Institute for Physics and Astrophysics in Munich.

  20. Digitale Archivierung papierbasierter Krankenakten von Studienpatienten – Eckpunktepapier des KKSN, der GMDS und der TMF unter Mitwirkung des BfArM und der Landesüberwachungsbehörde Nordrhein-Westfalen [Digital archiving of paper-based patient records of clinical trial subjects – a key issues paper of KKSN, GMDS, and TMF in collaboration with the Federal Institute for Drugs and Medical Devices (BfArM and the Health Authority Northrhine-Westphalia

    Directory of Open Access Journals (Sweden)

    Kohl, Christian D.

    2013-04-01

    Full Text Available [english] The management and maintenance of paper-based patient record archives involve high running costs. Therefore, many health care providers choose to digitize their paper records subsequently destroying the originals. By now, this is an established procedure for patient records from routine care.However, at present it is unclear under which circumstances the patient records of patients taking part in clinical trials can be destroyed after digitization. Paper-based original records may only be destroyed if their digital copies are recognized as source documents by both sponsors and authorities. The authors believe that this recognition should be possible, as long as the scanned paper-based records fulfill the requirements for certified copies according to the Note for Guidance (ICH-GCP. This requires that, based on the applied rules, it can be proven at any time that the existing digitization process is clearly regulated, and the resulting quality is regularly controlled and sufficiently high.The objective of this key issues paper is to present the manner in which the existing regulatory guidelines can be implemented to allow the digitized patient records being recognized as source documents.An English version of this article will be published in “Clinical Investigation” (Future Science .[german] Das Verwalten und Vorhalten von Archiven für papierbasierte Patientenakten verursacht hohe laufende Kosten. Viele Gesundheitsversorger sind daher dazu übergegangen, ihre Papierakten in einem Scan-Prozess zu digitalisieren und die Originalakten anschließend zu vernichten. Für die Patientenversorgung hat sich dieses Vorgehen bewährt.Zum gegenwärtigen Zeitpunkt ist jedoch unklar, unter welchen Voraussetzungen Krankenakten von Patienten, die an klinischen Studien teilnehmen, nach dem Digitalisieren vernichtet werden können. Die papierbasierten Originalakten können nur dann vernichtet werden, wenn deren digitale Kopien von Sponsoren und Beh

  1. Determination of irradiation temperature using SiC temperature monitors

    International Nuclear Information System (INIS)

    Maruyama, Tadashi; Onose, Shoji

    1999-01-01

    This paper describes a method for detecting the change in length of SiC temperature monitors and a discussion is made on the relationship between irradiation temperature and the recovery in length of SiC temperature monitors. The SiC specimens were irradiated in the experimental fast reactor JOYO' at the irradiation temperatures around 417 to 645degC (design temperature). The change in length of irradiated specimens was detected using a dilatometer with SiO 2 glass push rod in an infrared image furnace. The temperature at which recovery in macroscopic length begins was obtained from the annealing intersection temperature. The results of measurements indicated that a difference between annealing intersection temperature and the design temperature sometimes reached well over ±100degC. A calibration method to obtain accurate irradiation temperature was presented and compared with the design temperature. (author)

  2. The energy sector between the two poles of the free market system and the public service obligations. Potential and limitations of state control, with an emphasis on the act for reform of the energy industry law (ENG) and the EU Internal Market Directive; Der Energiesektor zwischen Marktwirtschaft und oeffentlicher Aufgabe. Moeglichkeiten und Grenzen staatlicher Steuerung unter besonderer Beruecksichtigung des Gesetzes zur Neuregelung des Energiewirtschaftsrechts und des Europarechts

    Energy Technology Data Exchange (ETDEWEB)

    Hoelzer, F.

    2000-07-01

    In Part A of the book it will be brought out that despite differing conceptual starting points and despite state control's way of working, there is no alternative to legal control. In co-operative models and consensual solutions in those states with private sector service providers, which exist in diverse forms in the energy sector, too, the law operates as a framework or regulatory warning, or it has a reserve function. An end to state control is not linked to that because the state remains responsible for the achievement of the goals the notification ans definition of which it undertakes as a public duty. The results found are discussed and confirmed in Part B of the book in connection with the reform of the legal framework of the energy industry (the German act named ENG). In Part C of the book it will be shown to what extent legal constitutional limitations stand in the way of state control in the energy sector. (orig./CB) [German] Im ersten Teil der Arbeit wird staatliche Steuerung durch Recht an Beispielen des Energiesektors untersucht, wobei insbesondere Fragen des Wirkens und der Erscheinungsformen staatlicher Steuerung sowie die Auswirkungen der Veraenderung staatlicher Steuerung auf die Rolle des Staates und auf das Verhaeltnis von Staat und Gesellschaft im Vordergrund stehen. Im zweiten Teil werden unter besonderer Beruecksichtigung der europarechtlichen Regelungen die Moeglichkeiten, rechtliche Grenzen und Maengel staatlicher Steuerung im bisherigen System der Elektrizitaetsversorgung in Deutschland dargestellt, da Reformen, um dem Steuerungsanspruch des Staates gerecht zu werden, diesezu beachten haben. Es wird u.a. untersucht, inwieweit Entstaatlichungsstrategien im Rahmen der Reformen im Energiesektor Anwendung finden. Im dritten Teil werden die verfassungsrechtlichen Restriktionen untersucht. (orig./CB)

  3. High temperature niobium alloys

    International Nuclear Information System (INIS)

    Wojcik, C.C.

    1991-01-01

    Niobium alloys are currently being used in various high temperature applications such as rocket propulsion, turbine engines and lighting systems. This paper presents an overview of the various commercial niobium alloys, including basic manufacturing processes, properties and applications. Current activities for new applications include powder metallurgy, coating development and fabrication of advanced porous structures for lithium cooled heat pipes

  4. High-temperature uncertainty

    International Nuclear Information System (INIS)

    Timusk, T.

    2005-01-01

    Recent experiments reveal that the mechanism responsible for the superconducting properties of cuprate materials is even more mysterious than we thought. Two decades ago, Georg Bednorz and Alex Mueller of IBM's research laboratory in Zurich rocked the world of physics when they discovered a material that lost all resistance to electrical current at the record temperature of 36 K. Until then, superconductivity was thought to be a strictly low-temperature phenomenon that required costly refrigeration. Moreover, the IBM discovery - for which Bednorz and Mueller were awarded the 1987 Nobel Prize for Physics - was made in a ceramic copper-oxide material that nobody expected to be particularly special. Proposed applications for these 'cuprates' abounded. High-temperature superconductivity, particularly if it could be extended to room temperature, offered the promise of levitating trains, ultra-efficient power cables, and even supercomputers based on superconducting quantum interference devices. But these applications have been slow to materialize. Moreover, almost 20 years on, the physics behind this strange state of matter remains a mystery. (U.K.)

  5. Dual temperature concentration system

    International Nuclear Information System (INIS)

    Spevack, J.S.

    1975-01-01

    In a dual temperature isotope exchange system--exemplified by exchange of deuterium and protium between water and hydrogen sulfide gas in hot and cold towers, in which the feed stream (water) containing the desired isotope is passed through a pair of towers maintained at different temperatures wherein it effects isotope exchange with countercurrently circulated auxiliary fluid (H 2 S) and is impoverished in said isotope and then disposed of, e.g. discharged to waste,--the flow of isotope enriched auxiliary fluid between said towers (hot H 2 S saturated with water vapor) is divided and a part thereof is adjusted in its temperature (to cold tower conditions) and then passed to the auxiliary fluid impoverishing (cold) tower, while the remainder of the divided flow of such enriched auxiliary fluid is passed through a subsequent isotope concentration treatment to produce a product more highly enriched in the desired isotope and wherein it is also adjusted in its temperature and is impoverished in said isotope during said subsequent treatment before it is delivered to the said auxiliary fluid impoverishing (cold) tower. Certain provisions are made for returning to the hot tower liquid carried as vapor by the remainder of the divided flow to the subsequent isotope concentration treatment, for recovering sensible and latent heat, and for reducing passage of auxiliary fluid to waste

  6. Low Temperature Plasma Medicine

    Science.gov (United States)

    Graves, David

    2013-10-01

    Ionized gas plasmas near room temperature are used in a remarkable number of technological applications mainly because they are extraordinarily efficient at exploiting electrical power for useful chemical and material transformations near room temperature. In this tutorial address, I will focus on the newest area of low temperature ionized gas plasmas (LTP), in this case operating under atmospheric pressure conditions, in which the temperature-sensitive material is living tissue. LTP research directed towards biomedical applications such as sterilization, surgery, wound healing and anti-cancer therapy has seen remarkable growth in the last 3-5 years, but the mechanisms responsible for the biomedical effects have remained mysterious. It is known that LTP readily create reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS (or RONS), in addition to a suite of other radical and non-radical reactive species, are essential actors in an important sub-field of aerobic biology termed ``redox'' (or oxidation-reduction) biology. I will review the evidence suggesting that RONS generated by plasmas are responsible for their observed therapeutic effects. Other possible bio-active mechanisms include electric fields, charges and photons. It is common in LTP applications that synergies between different mechanisms can play a role and I will review the evidence for synergies in plasma biomedicine. Finally, I will address the challenges and opportunities for plasma physicists to enter this novel, multidisciplinary field.

  7. High temperature storage loop :

    Energy Technology Data Exchange (ETDEWEB)

    Gill, David Dennis; Kolb, William J.

    2013-07-01

    A three year plan for thermal energy storage (TES) research was created at Sandia National Laboratories in the spring of 2012. This plan included a strategic goal of providing test capability for Sandia and for the nation in which to evaluate high temperature storage (>650ÀC) technology. The plan was to scope, design, and build a flow loop that would be compatible with a multitude of high temperature heat transfer/storage fluids. The High Temperature Storage Loop (HTSL) would be reconfigurable so that it was useful for not only storage testing, but also for high temperature receiver testing and high efficiency power cycle testing as well. In that way, HTSL was part of a much larger strategy for Sandia to provide a research and testing platform that would be integral for the evaluation of individual technologies funded under the SunShot program. DOEs SunShot program seeks to reduce the price of solar technologies to 6/kWhr to be cost competitive with carbon-based fuels. The HTSL project sought to provide evaluation capability for these SunShot supported technologies. This report includes the scoping, design, and budgetary costing aspects of this effort

  8. Fast Air Temperature Sensors

    DEFF Research Database (Denmark)

    Hendricks, Elbert

    1998-01-01

    The note documents briefly work done on a newly developed sensor for making fast temperature measurements on the air flow in the intake ports of an SI engine and in the EGR input line. The work reviewed has been carried out in close cooperation with Civ. Ing. Michael Føns, the author (IAU...

  9. High Temperature Electrolysis

    DEFF Research Database (Denmark)

    Elder, Rachael; Cumming, Denis; Mogensen, Mogens Bjerg

    2015-01-01

    High temperature electrolysis of carbon dioxide, or co-electrolysis of carbon dioxide and steam, has a great potential for carbon dioxide utilisation. A solid oxide electrolysis cell (SOEC), operating between 500 and 900. °C, is used to reduce carbon dioxide to carbon monoxide. If steam is also i...

  10. Temperature measurements by thermocouples

    International Nuclear Information System (INIS)

    Liermann, J.

    1975-01-01

    The measurement of a temperature (whatever the type of transducer used) raises three problems: the choice of transducer; where it should be placed; how it should be fixed and protected. These are the three main points examined, after a brief description of the most commonly used thermocouples [fr

  11. A temperature profiler

    Digital Repository Service at National Institute of Oceanography (India)

    Peshwe, V.B.; Desa, E.

    An instrument developed for measuring temperature profiles at sea in depth or time scales is described. PC-based programming offers flexibility in setting up the instrument for the mode of operation prior to each cast. A real time clock built...

  12. Temperature dependent anomalous statistics

    International Nuclear Information System (INIS)

    Das, A.; Panda, S.

    1991-07-01

    We show that the anomalous statistics which arises in 2 + 1 dimensional Chern-Simons gauge theories can become temperature dependent in the most natural way. We analyze and show that a statistic's changing phase transition can happen in these theories only as T → ∞. (author). 14 refs

  13. Estimation of bare soil surface temperature from air temperature and ...

    African Journals Online (AJOL)

    Soil surface temperature has critical influence on climate, agricultural and hydrological activities since it serves as a good indicator of the energy budget of the earth's surface. Two empirical models for estimating soil surface temperature from air temperature and soil depth temperature were developed. The coefficient of ...

  14. Relationship between body temperature and air temperature in ...

    African Journals Online (AJOL)

    Body temperatures of singing male Gryllus bimaculatus were measured for the first time. Body temperatures were strongly correlated with ambient temperature. This indicates that, unlike some other orthopterans, larger crickets are not dependent on an elevated body temperature for efficient calling. Our results confirm that it ...

  15. Astronaut James Lovell checks body temperature with oral temperature probe

    Science.gov (United States)

    1965-01-01

    Gemini 7 pilot Astronaut James A. Lovell Jr. has temperature check with oral temperature probe attached to his space suit during final preflight preparations for the Gemini 7 space mission. The temperature probe allows doctors to monitor astronauts body temperature at any time during the mission.

  16. High temperature materials and mechanisms

    CERN Document Server

    2014-01-01

    The use of high-temperature materials in current and future applications, including silicone materials for handling hot foods and metal alloys for developing high-speed aircraft and spacecraft systems, has generated a growing interest in high-temperature technologies. High Temperature Materials and Mechanisms explores a broad range of issues related to high-temperature materials and mechanisms that operate in harsh conditions. While some applications involve the use of materials at high temperatures, others require materials processed at high temperatures for use at room temperature. High-temperature materials must also be resistant to related causes of damage, such as oxidation and corrosion, which are accelerated with increased temperatures. This book examines high-temperature materials and mechanisms from many angles. It covers the topics of processes, materials characterization methods, and the nondestructive evaluation and health monitoring of high-temperature materials and structures. It describes the ...

  17. Zero Temperature Hope Calculations

    International Nuclear Information System (INIS)

    Rozsnyai, B. F.

    2002-01-01

    The primary purpose of the HOPE code is to calculate opacities over a wide temperature and density range. It can also produce equation of state (EOS) data. Since the experimental data at the high temperature region are scarce, comparisons of predictions with the ample zero temperature data provide a valuable physics check of the code. In this report we show a selected few examples across the periodic table. Below we give a brief general information about the physics of the HOPE code. The HOPE code is an ''average atom'' (AA) Dirac-Slater self-consistent code. The AA label in the case of finite temperature means that the one-electron levels are populated according to the Fermi statistics, at zero temperature it means that the ''aufbau'' principle works, i.e. no a priory electronic configuration is set, although it can be done. As such, it is a one-particle model (any Hartree-Fock model is a one particle model). The code is an ''ion-sphere'' model, meaning that the atom under investigation is neutral within the ion-sphere radius. Furthermore, the boundary conditions for the bound states are also set at the ion-sphere radius, which distinguishes the code from the INFERNO, OPAL and STA codes. Once the self-consistent AA state is obtained, the code proceeds to generate many-electron configurations and proceeds to calculate photoabsorption in the ''detailed configuration accounting'' (DCA) scheme. However, this last feature is meaningless at zero temperature. There is one important feature in the HOPE code which should be noted; any self-consistent model is self-consistent in the space of the occupied orbitals. The unoccupied orbitals, where electrons are lifted via photoexcitation, are unphysical. The rigorous way to deal with that problem is to carry out complete self-consistent calculations both in the initial and final states connecting photoexcitations, an enormous computational task. The Amaldi correction is an attempt to address this problem by distorting the

  18. High Temperature Piezoelectric Drill

    Science.gov (United States)

    Bao, Xiaoqi; Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea; Shrout, Tom

    2012-01-01

    Venus is one of the planets in the solar systems that are considered for potential future exploration missions. It has extreme environment where the average temperature is 460 deg C and its ambient pressure is about 90 atm. Since the existing actuation technology cannot maintain functionality under the harsh conditions of Venus, it is a challenge to perform sampling and other tasks that require the use of moving parts. Specifically, the currently available electromagnetic actuators are limited in their ability to produce sufficiently high stroke, torque, or force. In contrast, advances in developing electro-mechanical materials (such as piezoelectric and electrostrictive) have enabled potential actuation capabilities that can be used to support such missions. Taking advantage of these materials, we developed a piezoelectric actuated drill that operates at the temperature range up to 500 deg C and the mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) configuration. The detailed results of our study are presented in this paper

  19. High temperature materials characterization

    Science.gov (United States)

    Workman, Gary L.

    1990-01-01

    A lab facility for measuring elastic moduli up to 1700 C was constructed and delivered. It was shown that the ultrasonic method can be used to determine elastic constants of materials from room temperature to their melting points. The ease in coupling high frequency acoustic energy is still a difficult task. Even now, new coupling materials and higher power ultrasonic pulsers are being suggested. The surface was only scratched in terms of showing the full capabilities of either technique used, especially since there is such a large learning curve in developing proper methodologies to take measurements into the high temperature region. The laser acoustic system does not seem to have sufficient precision at this time to replace the normal buffer rod methodology.

  20. The temperature hydration kinetics

    Directory of Open Access Journals (Sweden)

    Mircea Oroian

    2017-07-01

    Full Text Available The aim of this study is to evaluate the hydration kinetics of lentil seeds (Lens culinaris in water at different temperatures (25, 32.5, 40, 55, 70 and 80 °C for assessing the adequacy of models for describing the absorption phenomena during soaking. The diffusion coefficient values were calculated using Fick’s model for spherical and hemispherical geometries and the values were in the range of 10−6 m2/s. The experimental data were fitted to Peleg, Sigmoidal, Weibull and Exponential models. The models adequacy was determined using regression coefficients (R2, root mean square error (RMSE and reduced chi-square (χ2. The Peleg model is the suitable one for predicting the experimental data. Temperature had a positive and significant effect on the water absorption capacities and absorption was an endothermic process.

  1. Engine Cylinder Temperature Control

    Science.gov (United States)

    Kilkenny, Jonathan Patrick; Duffy, Kevin Patrick

    2005-09-27

    A method and apparatus for controlling a temperature in a combustion cylinder in an internal combustion engine. The cylinder is fluidly connected to an intake manifold and an exhaust manifold. The method and apparatus includes increasing a back pressure associated with the exhaust manifold to a level sufficient to maintain a desired quantity of residual exhaust gas in the cylinder, and varying operation of an intake valve located between the intake manifold and the cylinder to an open duration sufficient to maintain a desired quantity of fresh air from the intake manifold to the cylinder, wherein controlling the quantities of residual exhaust gas and fresh air are performed to maintain the temperature in the cylinder at a desired level.

  2. Ultrahigh temperature intermetallic alloys

    Energy Technology Data Exchange (ETDEWEB)

    Brady, M.P.; Zhu, J.H.; Liu, C.T.; Tortorelli, P.F.; Wright, J.L.; Carmichael, C.A.; Walker, L.R. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.

    1997-12-01

    A new family of Cr-Cr{sub 2}X based alloys with fabricability, mechanical properties, and oxidation resistance superior to previously developed Cr-Cr{sub 2}Nb and Cr-Cr{sub 2}Zr based alloys has been identified. The new alloys can be arc-melted/cast without cracking, and exhibit excellent room temperature and high-temperature tensile strengths. Preliminary evaluation of oxidation behavior at 1100 C in air indicates that the new Cr-Cr{sub 2}X based alloys form an adherent chromia-based scale. Under similar conditions, Cr-Cr{sub 2}Nb and Cr-Cr{sub 2}Zr based alloys suffer from extensive scale spallation.

  3. Supersymmetry at finite temperature

    International Nuclear Information System (INIS)

    Oliveira, M.W. de.

    1986-01-01

    The consequences of the incorporation of finite temperature effects in fields theories are investigated. Particularly, we consider the sypersymmetric non-linear sigma model, calculating the effective potencial in the large N limit. Initially, we present the 1/N expantion formalism and, for the O(N) model of scalar field, we show the impossibility of spontaneous symmetry breaking. Next, we study the same model at finite temperature and in the presence of conserved charges (the O(N) symmetry's generator). We conclude that these conserved charges explicitly break the symmetry. We introduce a calculation method for the thermodynamic potential of the theory in the presence of chemical potentials. We present an introduction to Supersymmetry in the aim of describing some important concepts for the treatment at T>0. We show that Suppersymmetry is broken for any T>0, in opposition to what one expects, by the solution of the Hierachy Problem. (author) [pt

  4. Temperature measuring device

    International Nuclear Information System (INIS)

    Brixy, H.

    1977-01-01

    The temperature measuring device is equipped with an electric resistor installed within a metal shroud tube so as to be insulated from it, the noise voltage of which resistor is fed to a measuring unit. The measuring junctions of one or two thermocouples are connected with the electric resistor and the legs of one or both thermocouples can be connected to the measuring unit by means of a switch. (orig.) [de

  5. Low temperatures - hot topic

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1988-09-15

    Neutrino mass measurements, next-generation double beta experiments, solar neutrino detection, searches for magnetic monopoles and the challenge of discovering what most of the Universe is made of (dark matter), not to mention axions (cosmic and solar), supersymmetric neutral particles and cosmic neutrinos. All this physics could use cryogenic techniques. Thus the second European Workshop on Low Temperature Devices for the Detection of Low Energy Neutrinos and Dark Matter, held at LAPP (Annecy) in May, covered an active and promising field.

  6. Low temperatures - hot topic

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    Neutrino mass measurements, next-generation double beta experiments, solar neutrino detection, searches for magnetic monopoles and the challenge of discovering what most of the Universe is made of (dark matter), not to mention axions (cosmic and solar), supersymmetric neutral particles and cosmic neutrinos. All this physics could use cryogenic techniques. Thus the second European Workshop on Low Temperature Devices for the Detection of Low Energy Neutrinos and Dark Matter, held at LAPP (Annecy) in May, covered an active and promising field

  7. High temperature materials

    International Nuclear Information System (INIS)

    2003-01-01

    The aim of this workshop is to share the needs of high temperature and nuclear fuel materials for future nuclear systems, to take stock of the status of researches in this domain and to propose some cooperation works between the different research organisations. The future nuclear systems are the very high temperature (850 to 1200 deg. C) gas cooled reactors (GCR) and the molten salt reactors (MSR). These systems include not only the reactor but also the fabrication and reprocessing of the spent fuel. This document brings together the transparencies of 13 communications among the 25 given at the workshop: 1) characteristics and needs of future systems: specifications, materials and fuel needs for fast spectrum GCR and very high temperature GCR; 2) high temperature materials out of neutron flux: thermal barriers: materials, resistance, lifetimes; nickel-base metal alloys: status of knowledge, mechanical behaviour, possible applications; corrosion linked with the gas coolant: knowledge and problems to be solved; super-alloys for turbines: alloys for blades and discs; corrosion linked with MSR: knowledge and problems to be solved; 3) materials for reactor core structure: nuclear graphite and carbon; fuel assembly structure materials of the GCR with fast neutron spectrum: status of knowledge and ceramics and cermets needs; silicon carbide as fuel confinement material, study of irradiation induced defects; migration of fission products, I and Cs in SiC; 4) materials for hydrogen production: status of the knowledge and needs for the thermochemical cycle; 5) technologies: GCR components and the associated material needs: compact exchangers, pumps, turbines; MSR components: valves, exchangers, pumps. (J.S.)

  8. Temperature responsive track membranes

    International Nuclear Information System (INIS)

    Omichi, H.; Yoshido, M.; Asano, M.; Tamada, H.

    1994-01-01

    A new track membrane was synthesized by introducing polymeric hydrogel to films. Such a monomer as amino acid group containing acryloyl or methacryloyl was either co-polymerized with diethylene glycol-bis-ally carbonate followed by on beam irradiation and chemical etching, or graft co-polymerized onto a particle track membrane of CR-39. The pore size was controlled in water by changing the water temperature. Some films other than CR-39 were also examined. (author). 11 refs, 7 figs

  9. Portable Body Temperature Conditioner

    Science.gov (United States)

    2014-12-01

    temperature is 36.0o C. The patient complains of severe abdominal pain and intra- abdominal injury is suspected. In this scenario the patient is...hypothermia will shiver, experience pain , and on a whole be really uncomfortable. If they are sufficiently obtunded to require this therapy then they...Convective hyper- hypothermia water blankets/wraps Single-Use Blanket Maxi-Therm Adult Box 5 $127.00 Pediatric Box 5 $90.00 Infant Box 5 $72.00

  10. Low-Temperature Supercapacitors

    Science.gov (United States)

    Brandon, Erik J.; West, William C.; Smart, Marshall C.

    2008-01-01

    An effort to extend the low-temperature operational limit of supercapacitors is currently underway. At present, commercially available non-aqueous supercapacitors are rated for a minimum operating temperature of -40 C. A capability to operate at lower temperatures would be desirable for delivering power to systems that must operate in outer space or in the Polar Regions on Earth. Supercapacitors (also known as double-layer or electrochemical capacitors) offer a high power density (>1,000 W/kg) and moderate energy density (about 5 to 10 Wh/kg) technology for storing energy and delivering power. This combination of properties enables delivery of large currents for pulsed applications, or alternatively, smaller currents for low duty cycle applications. The mechanism of storage of electric charge in a supercapacitor -- at the electrical double-layer formed at a solid-electrode/liquid-electrolyte interface -- differs from that of a primary or secondary electrochemical cell (i.e., a battery) in such a manner as to impart a long cycle life (typically >10(exp 6) charge/discharge cycles).

  11. Low-temperature carbonization

    Energy Technology Data Exchange (ETDEWEB)

    Strankmuller, J

    1954-01-01

    The low-temperature carbonization plant at Boehlen in Eastern Germany (the first in which Lurgi type ovens were installed) worked with a throughput of 300 tons of brown-coal briquets per day per oven since 1936, later increased to 365 tons per day. The rising demand for low-temperature tar for hydrogenation purposes led to development of a modified oven of 450 tons throughput. This was achieved by stepping up the flow of the circulating gas and air mixture from 420,000 to 560,000 cubic feet per hour and by additional rows of V-shaped deflectors across the width of the oven chamber, which break up and loosen the charge, thus reducing cooling-gas pressure and allowing a greater flow of scavenging gas. The distance traversed by each briquet is nearly doubled, and the temperature gradient is less. It is claimed that the tar and the coke from modified ovens are of comparable quality. The compressive strength of the briquets was found to have an appreciable effect on the output. Better qts the chemistry, mechanism and thermodynamics of the Fischer-Tropsch reaction and aectromagnetic radiation.

  12. Ion temperature gradient instability

    International Nuclear Information System (INIS)

    1989-01-01

    Anomalous ion thermal conductivity remains an open physics issue for the present generation of high temperature Tokamaks. It is generally believed to be due to Ion Temperature Gradient Instability (η i mode). However, it has been difficult, if not impossible to identify this instability and study the anomalous transport due to it, directly. Therefore the production and identification of the mode is pursued in the simpler and experimentally convenient configuration of the Columbia Linear Machine (CLM). CLM is a steady state machine which already has all the appropriate parameters, except η i . This parameter is being increased to the appropriate value of the order of 1 by 'feathering' a tungsten screen located between the plasma source and the experimental cell to flatten the density profile and appropriate redesign of heating antennas to steepen the ion temperature profile. Once the instability is produced and identified, a thorough study of the characteristics of the mode can be done via a wide range of variation of all the critical parameters: η i , parallel wavelength, etc

  13. A new temperature collection system

    International Nuclear Information System (INIS)

    Kong Wenchuang; Wang Daihua; Zhang Zhijie

    2011-01-01

    According to the characteristics of explosion field temperature testing, a new temperature collection system based on complex programmable logic device (CPLD), single chip microcontroller (SCM) and static ram (SRAM) is proposed. The system adopts the NANMAC E12 type of thermocouple as the temperature sensor, DS600 temperature sensor for cold temperature compensation, with rapid synchronous collection, trigger and working parameters adjustable characteristics. The system used SCM combined with USB communication interface, easy operation and reliable. (authors)

  14. GlobTemperature

    Science.gov (United States)

    Ghent, Darren; Remedios, John; Bruniquel, Jerome; Sardou, Olivier; Trigo, Isabel; Merchant, Chris; Bulgin, Claire; Goettsche, Frank; Olesen, Folke; Prigent, Catherine; Pinnock, Simon

    2014-05-01

    Land surface temperature (LST) is the mean radiative skin temperature of an area of land resulting from the mean balance of solar heating and land-atmosphere cooling fluxes. It is a basic determinant of the terrestrial thermal behaviour, as it controls the effective radiating temperature of the Earth's surface. The sensitivity of LST to soil moisture and vegetation cover means it is an important component in numerous applications. For instance, LST is a key boundary condition in land surface models, which determine the surface to atmosphere fluxes of heat, water and carbon; thus influencing cloud cover, precipitation and atmospheric chemistry predictions within General Circulation Models. Changes in land-surface cover can affect global climate, and also can be identified by changes in their surface temperatures. With the demand of LST data from Earth Observation currently experiencing considerable growth it is important that the users of this data are appropriately engaged by the LST community. The GlobTemperature project under the Data User Element of ESA's 4th Earth Observation Envelope Programme (2013-2017) aims to promote the wider uptake of global-scale satellite LST by the research and operational user communities. As such, the programme of work is focussed on achieving some innovative milestones for LST data which include: detailed global merged geostationary (GEO) and low earth orbit (LEO) data sets with estimates of both clear-sky and under-cloud LST; a first Climate Data Record for LST for the ATSR series of instruments; and the provision of a globally representative and consistent in-situ validation and intercomparison matchup database. Furthermore, the strength of such a venture lies in the coherence and openness of the interactions with the LST and user communities. For instance: detailed user input into the specifications and subsequent testing of the LST data sets; sustained access to data in a user-friendly manner through common data formats; and

  15. Crowdsourcing urban air temperatures from smartphone battery temperatures

    Science.gov (United States)

    Overeem, Aart; Robinson, James C. R.; Leijnse, Hidde; Steeneveld, Gert-Jan; Horn, Berthold K. P.; Uijlenhoet, Remko

    2014-05-01

    Accurate air temperature observations in urban areas are important for meteorology and energy demand planning. They are indispensable to study the urban heat island effect and the adverse effects of high temperatures on human health. However, the availability of temperature observations in cities is often limited. Here we show that relatively accurate air temperature information for the urban canopy layer can be obtained from an alternative, nowadays omnipresent source: smartphones. In this study, battery temperatures were collected by an Android application for smartphones. It has been shown that a straightforward heat transfer model can be employed to estimate daily mean air temperatures from smartphone battery temperatures for eight major cities around the world. The results demonstrate the enormous potential of this crowdsourcing application for real-time temperature monitoring in densely populated areas. Battery temperature data were collected by users of an Android application for cell phones (opensignal.com). The application automatically sends battery temperature data to a server for storage. In this study, battery temperatures are averaged in space and time to obtain daily averaged battery temperatures for each city separately. A regression model, which can be related to a physical model, is employed to retrieve daily air temperatures from battery temperatures. The model is calibrated with observed air temperatures from a meteorological station of an airport located in or near the city. Time series of air temperatures are obtained for each city for a period of several months, where 50% of the data is for independent verification. The methodology has been applied to Buenos Aires, London, Los Angeles, Paris, Mexico City, Moscow, Rome, and Sao Paulo. The evolution of the retrieved air temperatures often correspond well with the observed ones. The mean absolute error of daily air temperatures is less than 2 degrees Celsius, and the bias is within 1 degree

  16. High temperature superconductors

    CERN Document Server

    Paranthaman, Parans

    2010-01-01

    This essential reference provides the most comprehensive presentation of the state of the art in the field of high temperature superconductors. This growing field of research and applications is currently being supported by numerous governmental and industrial initiatives in the United States, Asia and Europe to overcome grid energy distribution issues. The technology is particularly intended for densely populated areas. It is now being commercialized for power-delivery devices, such as power transmission lines and cables, motors and generators. Applications in electric utilities include current limiters, long transmission lines and energy-storage devices that will help industries avoid dips in electric power.

  17. Residential Indoor Temperature Study

    Energy Technology Data Exchange (ETDEWEB)

    Booten, Chuck [National Renewable Energy Lab. (NREL), Golden, CO (United States); Robertson, Joseph [National Renewable Energy Lab. (NREL), Golden, CO (United States); Christensen, Dane [National Renewable Energy Lab. (NREL), Golden, CO (United States); Heaney, Mike [Arrow Electronics, Centennial, CO (United States); Brown, David [Univ. of Virginia, Charlottesville, VA (United States); Norton, Paul [Norton Energy Research and Development, Boulder, CO (United States); Smith, Chris [Ingersoll-Rand Corp., Dublin (Ireland)

    2017-04-07

    In this study, we are adding to the body of knowledge around answering the question: What are good assumptions for HVAC set points in U.S. homes? We collected and analyzed indoor temperature data from US homes using funding from the U.S. Department of Energy's Building America (BA) program, due to the program's reliance on accurate energy simulation of homes. Simulations are used to set Building America goals, predict the impact of new building techniques and technologies, inform research objectives, evaluate home performance, optimize efficiency packages to meet savings goals, customize savings approaches to specific climate zones, and myriad other uses.

  18. High temperature radioisotope capsule

    International Nuclear Information System (INIS)

    Bradshaw, G.B.

    1976-01-01

    A high temperature radioisotope capsule made up of three concentric cylinders, with the isotope fuel located within the innermost cylinder is described. The innermost cylinder has hemispherical ends and is constructed of a tantalum alloy. The intermediate cylinder is made of a molybdenum alloy and is capable of withstanding the pressure generated by the alpha particle decay of the fuel. The outer cylinder is made of a platinum alloy of high resistance to corrosion. A gas separates the innermost cylinder from the intermediate cylinder and the intermediate cylinder from the outer cylinder

  19. Ambient temperature signalling in plants.

    Science.gov (United States)

    Wigge, Philip A

    2013-10-01

    Plants are exposed to daily and seasonal fluctuations in temperature. Within the 'ambient' temperature range (about 12-27°C for Arabidopsis) temperature differences have large effects on plant growth and development, disease resistance pathways and the circadian clock without activating temperature stress pathways. It is this developmental sensing and response to non-stressful temperatures that will be covered in this review. Recent advances have revealed key players in mediating temperature signals. The bHLH transcription factor PHYTOCHROME INTERACTING FACTOR4 (PIF4) has been shown to be a hub for multiple responses to warmer temperature in Arabidopsis, including flowering and hypocotyl elongation. Changes in chromatin state are involved in transmitting temperature signals to the transcriptome. Determining the precise mechanisms of temperature perception represents an exciting goal for the field. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Teaching Temperature with Technology

    Science.gov (United States)

    Schillaci, Michael

    2010-10-01

    In recent years it has become very popular to introduce computational tools and/or simulations into the classroom. While the intention of this classroom addition is often meant to help elucidate a particular physical phenomena, teachers at ALL levels --- whether graduate or undergraduate, secondary- or middle-school --- may miss important teaching moments by either relying upon or struggling with the technology! I will demonstrate this phenomena with a sample teaching module developed at our instiitution that seeks to discover the relationship between temperature and latitude by having students gather data (e.g., average monthly temperature for a chosen city) from various world wide web resources. This task may be very difficult for students and teachers for reasons ranging from slow connection speeds to an inability to plot and interpret data.I will wrap up by demonstarting a simple Maple routine that will produce the graphs easily and discuss ways in which this kind of top-down solution may be the best bet for using and teaching technology at all levels.

  1. The relationship between body and ambient temperature and corneal temperature

    DEFF Research Database (Denmark)

    Kessel, Line; Johnson, Leif; Arvidsson, Henrik Sven

    2010-01-01

    Exposure to elevated ambient temperatures has been mentioned as a risk factor for common eye diseases, primarily presbyopia and cataract. The aim of the present study was to examine the relationship among ambient, cornea, and body core temperature.......Exposure to elevated ambient temperatures has been mentioned as a risk factor for common eye diseases, primarily presbyopia and cataract. The aim of the present study was to examine the relationship among ambient, cornea, and body core temperature....

  2. Crowdsourcing urban air temperatures from smartphone battery temperatures

    NARCIS (Netherlands)

    Overeem, A.; Robinson, J.C.R.; Leijnse, H.; Steeneveld, G.J.; Horn, B.K.P.; Uijlenhoet, R.

    2013-01-01

    [1] Accurate air temperature observations in urban areas are important for meteorology and energy demand planning. They are indispensable to study the urban heat island effect and the adverse effects of high temperatures on human health. However, the availability of temperature observations in

  3. Temperature measurement in the sea

    Digital Repository Service at National Institute of Oceanography (India)

    Krishnamacharyulu, R.J.; Rao, L.V.G.

    The importance of measuring sea temperature is explained and the various methods employed for this purpose are reviewed. Instruments used for spot measurement of water temperature at the sea surface and at discrete depths (bucket thermometer...

  4. High temperature superconductor accelerator magnets

    NARCIS (Netherlands)

    van Nugteren, J.

    2016-01-01

    For future particle accelerators bending dipoles are considered with magnetic fields exceeding 20T. This can only be achieved using high temperature superconductors (HTS). These exhibit different properties from classical low temperature superconductors and still require significant research and

  5. Strong interaction at finite temperature

    Indian Academy of Sciences (India)

    Quantum chromodynamics; finite temperature; chiral perturbation theory; QCD sum rules. PACS Nos 11.10. ..... at finite temperature. The self-energy diagrams of figure 2 modify it to ..... method of determination at present. Acknowledgement.

  6. Dual reference point temperature interrogating method for distributed temperature sensor

    International Nuclear Information System (INIS)

    Ma, Xin; Ju, Fang; Chang, Jun; Wang, Weijie; Wang, Zongliang

    2013-01-01

    A novel method based on dual temperature reference points is presented to interrogate the temperature in a distributed temperature sensing (DTS) system. This new method is suitable to overcome deficiencies due to the impact of DC offsets and the gain difference in the two signal channels of the sensing system during temperature interrogation. Moreover, this method can in most cases avoid the need to calibrate the gain and DC offsets in the receiver, data acquisition and conversion. An improved temperature interrogation formula is presented and the experimental results show that this method can efficiently estimate the channel amplification and system DC offset, thus improving the system accuracy. (letter)

  7. Tevatron lower temperature operation

    International Nuclear Information System (INIS)

    Theilacker, J.C.

    1994-07-01

    This year saw the completion of three accelerator improvement projects (AIP) and two capital equipment projects pertaining to the Tevatron cryogenic system. The projects result in the ability to operate the Tevatron at lower temperature, and thus higher energy. Each project improves a subsystem by expanding capabilities (refrigerator controls), ensuring reliability (valve box, subatmospheric hardware, and compressor D), or enhancing performance (cold compressors and coldbox II). In January of 1994, the Tevatron operated at an energy of 975 GeV for the first time. This was the culmination, of many years of R ampersand D, power testing in a sector (one sixth) of the Tevatron, and final system installation during the summer of 1993. Although this is a modest increase in energy, the discovery potential for the Top quark is considerably improved

  8. Variable temperature superconducting microscope

    Science.gov (United States)

    Cheng, Bo; Yeh, W. J.

    2000-03-01

    We have developed and tested a promising type of superconducting quantum interference device (SQUID) microscope, which can be used to detect vortex motion and can operate in magnetic fields over a large temperature range. The system utilizes a single-loop coupling transformer, consisting of a patterned high Tc superconducting thin film. At one end of the transformer, a 20 μm diam detecting loop is placed close to the sample. At the other end, a large loop is coupled to a NbTi coil, which is connected to a low Tc SQUID sensor. Transformers in a variety of sizes have been tested and calibrated. The results show that the system is capable of detecting the motion of a single vortex. We have used the microscope to study the behavior of moving vortices at various positions in a YBa2Cu3O7 thin film bridge.

  9. Hadrons at finite temperature

    CERN Document Server

    Mallik, Samirnath

    2016-01-01

    High energy laboratories are performing experiments in heavy ion collisions to explore the structure of matter at high temperature and density. This elementary book explains the basic ideas involved in the theoretical analysis of these experimental data. It first develops two topics needed for this purpose, namely hadron interactions and thermal field theory. Chiral perturbation theory is developed to describe hadron interactions and thermal field theory is formulated in the real-time method. In particular, spectral form of thermal propagators is derived for fields of arbitrary spin and used to calculate loop integrals. These developments are then applied to find quark condensate and hadron parameters in medium, including dilepton production. Finally, the non-equilibrium method of statistical field theory to calculate transport coefficients is reviewed. With technical details explained in the text and appendices, this book should be accessible to researchers as well as graduate students interested in thermal ...

  10. High temperature metallic recuperator

    Science.gov (United States)

    Ward, M. E.; Solmon, N. G.; Smeltzer, C. E.

    1981-06-01

    An industrial 4.5 MM Btu/hr axial counterflow recuperator, fabricated to deliver 1600 F combustion air, was designed to handle rapid cyclic loading, a long life, acceptable costs, and a low maintenance requirement. A cost benefit anlysis of a high temperature waste heat recovery system utilizing the recurperator and components capable of 1600 F combustion air preheat shows that this system would have a payback period of less than two years. Fifteen companies and industrial associations were interviewed and expressed great interest in recuperation in large energy consuming industries. Determination of long term environmental effects on candidate recuperator tubing alloys was completed. Alloys found to be acceptable in the 2200 F flue gas environment of a steel billet reheat furnace, were identified.

  11. Does Carbon Dioxide Predict Temperature?

    OpenAIRE

    Mytty, Tuukka

    2013-01-01

    Does carbon dioxide predict temperature? No it does not, in the time period of 1880-2004 with the carbon dioxide and temperature data used in this thesis. According to the Inter Governmental Panel on Climate Change(IPCC) carbon dioxide is the most important factor in raising the global temperature. Therefore, it is reasonable to assume that carbon dioxide truly predicts temperature. Because this paper uses observational data it has to be kept in mind that no causality interpretation can be ma...

  12. A survey of temperature measurement

    International Nuclear Information System (INIS)

    Saltvold, J.R.

    1976-03-01

    Many different techniques for measuring temperature have been surveyed and are discussed. The concept of temperature and the physical phenomena used in temperature measurement are also discussed. Extensive tables are presented in which the range and accuracy of the various techniques and other related data are included. (author)

  13. Axial anomaly at finite temperature

    International Nuclear Information System (INIS)

    Chaturvedi, S.; Gupte, Neelima; Srinivasan, V.

    1985-01-01

    The Jackiw-Bardeen-Adler anomaly for QED 4 and QED 2 are calculated at finite temperature. It is found that the anomaly is independent of temperature. Ishikawa's method [1984, Phys. Rev. Lett. vol. 53 1615] for calculating the quantised Hall effect is extended to finite temperature. (author)

  14. Battery system with temperature sensors

    Science.gov (United States)

    Wood, Steven J.; Trester, Dale B.

    2012-11-13

    A battery system to monitor temperature includes at least one cell with a temperature sensing device proximate the at least one cell. The battery system also includes a flexible member that holds the temperature sensor proximate to the at least one cell.

  15. High Temperature Superconductor Machine Prototype

    DEFF Research Database (Denmark)

    Mijatovic, Nenad; Jensen, Bogi Bech; Træholt, Chresten

    2011-01-01

    A versatile testing platform for a High Temperature Superconductor (HTS) machine has been constructed. The stationary HTS field winding can carry up to 10 coils and it is operated at a temperature of 77K. The rotating armature is at room temperature. Test results and performance for the HTS field...

  16. Temperature dependence of surface nanobubbles

    NARCIS (Netherlands)

    Berkelaar, R.P.; Seddon, James Richard Thorley; Zandvliet, Henricus J.W.; Lohse, Detlef

    2012-01-01

    The temperature dependence of nanobubbles was investigated experimentally using atomic force microscopy. By scanning the same area of the surface at temperatures from 51 °C to 25 °C it was possible to track geometrical changes of individual nanobubbles as the temperature was decreased.

  17. Advances in high temperature chemistry

    CERN Document Server

    Eyring, Leroy

    1969-01-01

    Advances in High Temperature Chemistry, Volume 2 covers the advances in the knowledge of the high temperature behavior of materials and the complex and unfamiliar characteristics of matter at high temperature. The book discusses the dissociation energies and free energy functions of gaseous monoxides; the matrix-isolation technique applied to high temperature molecules; and the main features, the techniques for the production, detection, and diagnosis, and the applications of molecular beams in high temperatures. The text also describes the chemical research in streaming thermal plasmas, as w

  18. High-Temperature Piezoelectric Sensing

    Directory of Open Access Journals (Sweden)

    Xiaoning Jiang

    2013-12-01

    Full Text Available Piezoelectric sensing is of increasing interest for high-temperature applications in aerospace, automotive, power plants and material processing due to its low cost, compact sensor size and simple signal conditioning, in comparison with other high-temperature sensing techniques. This paper presented an overview of high-temperature piezoelectric sensing techniques. Firstly, different types of high-temperature piezoelectric single crystals, electrode materials, and their pros and cons are discussed. Secondly, recent work on high-temperature piezoelectric sensors including accelerometer, surface acoustic wave sensor, ultrasound transducer, acoustic emission sensor, gas sensor, and pressure sensor for temperatures up to 1,250 °C were reviewed. Finally, discussions of existing challenges and future work for high-temperature piezoelectric sensing are presented.

  19. Micro-Mechanical Temperature Sensors

    DEFF Research Database (Denmark)

    Larsen, Tom

    Temperature is the most frequently measured physical quantity in the world. The field of thermometry is therefore constantly evolving towards better temperature sensors and better temperature measurements. The aim of this Ph.D. project was to improve an existing type of micro-mechanical temperature...... sensor or to develop a new one. Two types of micro-mechanical temperature sensors have been studied: Bilayer cantilevers and string-like beam resonators. Both sensor types utilize thermally generated stress. Bilayer cantilevers are frequently used as temperature sensors at the micro-scale, and the goal....... The reduced sensitivity was due to initial bending of the cantilevers and poor adhesion between the two cantilever materials. No further attempts were made to improve the sensitivity of bilayer cantilevers. The concept of using string-like resonators as temperature sensors has, for the first time, been...

  20. Bradycardia During Targeted Temperature Management

    DEFF Research Database (Denmark)

    Thomsen, Jakob Hartvig; Nielsen, Niklas; Hassager, Christian

    2016-01-01

    OBJECTIVES: Bradycardia is common during targeted temperature management, likely being a physiologic response to lower body temperature, and has recently been associated with favorable outcome following out-of-hospital cardiac arrest in smaller observational studies. The present study sought...... to confirm this finding in a large multicenter cohort of patients treated with targeted temperature management at 33°C and explore the response to targeted temperature management targeting 36°C. DESIGN: Post hoc analysis of a prospective randomized study. SETTING: Thirty-six ICUs in 10 countries. PATIENTS......: We studied 447 (targeted temperature management = 33°C) and 430 (targeted temperature management = 36°C) comatose out-of-hospital cardiac arrest patients with available heart rate data, randomly assigned in the targeted temperature management trial from 2010 to 2013. INTERVENTIONS: Targeted...

  1. Quantum entanglement at negative temperature

    International Nuclear Information System (INIS)

    Furman, G B; Meerovich, V M; Sokolovsky, V L

    2013-01-01

    An isolated spin system that is in internal thermodynamic equilibrium and that has an upper limit to its allowed energy states can possess a negative temperature. We calculate the thermodynamic characteristics and the concurrence in this system over the entire range of positive and negative temperatures. Our calculation was performed for different real structures, which can be used in experiments. It is found that the temperature dependence of the concurrence is substantially asymmetrical similarly to other thermodynamic characteristics. At a negative temperature the maximum concurrence and the absolute temperature of the entanglement appearance are significantly larger than those at a positive temperature. The concurrence can be characterized by two dimensionless parameters: the ratio between the Zeeman and dipolar energies and the ratio of the thermal and dipolar energies. It was shown that for all considered structures the dimensionless temperatures of the transition between entanglement and separability of the first and second spins are independent of spin structure and the number of spins. (paper)

  2. High temperature interface superconductivity

    International Nuclear Information System (INIS)

    Gozar, A.; Bozovic, I.

    2016-01-01

    Highlight: • This review article covers the topic of high temperature interface superconductivity. • New materials and techniques used for achieving interface superconductivity are discussed. • We emphasize the role played by the differences in structure and electronic properties at the interface with respect to the bulk of the constituents. - Abstract: High-T_c superconductivity at interfaces has a history of more than a couple of decades. In this review we focus our attention on copper-oxide based heterostructures and multi-layers. We first discuss the technique, atomic layer-by-layer molecular beam epitaxy (ALL-MBE) engineering, that enabled High-T_c Interface Superconductivity (HT-IS), and the challenges associated with the realization of high quality interfaces. Then we turn our attention to the experiments which shed light on the structure and properties of interfacial layers, allowing comparison to those of single-phase films and bulk crystals. Both ‘passive’ hetero-structures as well as surface-induced effects by external gating are discussed. We conclude by comparing HT-IS in cuprates and in other classes of materials, especially Fe-based superconductors, and by examining the grand challenges currently laying ahead for the field.

  3. Temperature measurement with neutrons

    International Nuclear Information System (INIS)

    Bizard, G.; Durand, D.; Lecolley, J.F.; Lefebvres, F.; Marques, M.; Peter, J.; Tamain, B.

    1998-01-01

    The results presented in this report were obtained from the information provided by charged products. Another alternative consists in detecting the neutrons abundantly emitted particularly by heavy nuclei. The residue channel was studied in the 40 Ar + 197 Au at 60 MeV/nucleon by means of the neutron multidetector DEMON. The evolution of the multiplicity of neutrons emitted backwards in the framework of the heavy nucleus forwardly detected as a function of the residue velocity by a silicon detector, placed at 8 degrees and at 24.5 cm from target, agrees with the expected results i.e. an increase with the residue velocity hence with the collision violence. For the same detector the first measurements show similarly a linear increase of the apparent temperature of 4.0 to around 6.5 MeV for residue velocities varying from 0.5 to 1.3 cm/ns and masses ranging from 140 to 160 uma. This first results of the analysis show therefore a good behaviour of the assembly and especially of the couple DeMoN-SyReP

  4. Core body temperature in obesity.

    Science.gov (United States)

    Heikens, Marc J; Gorbach, Alexander M; Eden, Henry S; Savastano, David M; Chen, Kong Y; Skarulis, Monica C; Yanovski, Jack A

    2011-05-01

    A lower core body temperature set point has been suggested to be a factor that could potentially predispose humans to develop obesity. We tested the hypothesis that obese individuals have lower core temperatures than those in normal-weight individuals. In study 1, nonobese [body mass index (BMI; in kg/m(2)) temperature-sensing capsules, and we measured core temperatures continuously for 24 h. In study 2, normal-weight (BMI of 18-25) and obese subjects swallowed temperature-sensing capsules to measure core temperatures continuously for ≥48 h and kept activity logs. We constructed daily, 24-h core temperature profiles for analysis. Mean (±SE) daily core body temperature did not differ significantly between the 35 nonobese and 46 obese subjects (36.92 ± 0.03°C compared with 36.89 ± 0.03°C; P = 0.44). Core temperature 24-h profiles did not differ significantly between 11 normal-weight and 19 obese subjects (P = 0.274). Women had a mean core body temperature ≈0.23°C greater than that of men (36.99 ± 0.03°C compared with 36.76 ± 0.03°C; P body temperature. It may be necessary to study individuals with function-altering mutations in core temperature-regulating genes to determine whether differences in the core body temperature set point affect the regulation of human body weight. These trials were registered at clinicaltrials.gov as NCT00428987 and NCT00266500.

  5. Temperature measurements in thermonuclear plasmas

    International Nuclear Information System (INIS)

    Breton, D.

    1958-01-01

    The temperatures needed to produce thermonuclear reactions are of the order of several million degrees Kelvin. Devising methods for measuring such temperatures has been the subject of research in many countries. In order to present the problem clearly and to demonstrate its importance, the author reviews the various conditions which must be fulfilled in order that reactions may be qualified as thermonuclear. The relationship between the temperature and the cross-section of the reactions is studied, and it is shown that the notion of temperature in the plasmas is complex, which leads to a consideration of the temperature of the ions and that of the electrons. None of the methods for the temperature measurements is completely satisfactory because of the hypotheses which must be made, and which are seldom fulfilled during high-intensity discharges in the plasmas. In practice it is necessary to use several methods simultaneously. (author) [fr

  6. Central control of body temperature.

    Science.gov (United States)

    Morrison, Shaun F

    2016-01-01

    Central neural circuits orchestrate the behavioral and autonomic repertoire that maintains body temperature during environmental temperature challenges and alters body temperature during the inflammatory response and behavioral states and in response to declining energy homeostasis. This review summarizes the central nervous system circuit mechanisms controlling the principal thermoeffectors for body temperature regulation: cutaneous vasoconstriction regulating heat loss and shivering and brown adipose tissue for thermogenesis. The activation of these thermoeffectors is regulated by parallel but distinct efferent pathways within the central nervous system that share a common peripheral thermal sensory input. The model for the neural circuit mechanism underlying central thermoregulatory control provides a useful platform for further understanding of the functional organization of central thermoregulation, for elucidating the hypothalamic circuitry and neurotransmitters involved in body temperature regulation, and for the discovery of novel therapeutic approaches to modulating body temperature and energy homeostasis.

  7. Dynamical calculation of nuclear temperature

    International Nuclear Information System (INIS)

    Zheng Yuming

    1998-01-01

    A new dynamical approach for measuring the temperature of a Hamiltonian dynamical system in the microcanonical ensemble of thermodynamics is presented. It shows that under the hypothesis of ergodicity the temperature can be computed as a time average of a function on the energy surface. This method not only yields an efficient computational approach for determining the temperature, but also provides an intrinsic link between dynamical system theory and the statistical mechanics of Hamiltonian system

  8. Finite temperature instability for compactification

    International Nuclear Information System (INIS)

    Accetta, F.S.; Kolb, E.W.

    1986-03-01

    We consider finite temperature effects upon theories with extra dimensions compactified via vacuum stress energy (Casimir) effects. For sufficiently high temperature, a static configuration for the internal space is impossible. At somewhat lower temperatures, there is an instability due to thermal fluctuations of radius of the compact dimensions. For both cases, the Universe can evolve to a de Sitter-like expansion of all dimensions. Stability to late times constrains the initial entropy of the universe. 28 refs., 1 fig., 2 tabs

  9. Thermoluminescent system for low temperatures

    International Nuclear Information System (INIS)

    Rosa, L.A.R. da; Caldas, L.V.E.; Leite, N.G.

    1988-09-01

    A system for measurements of the thermoluminescent glow curve, the thermoluminescent emission spectrum and the optical absorption spectrum of solid samples, from liquid nitrogen temperature up to 473 K, is reported. A specially designed temperature programmer provides a linear heating of the sample at a wide range of selectable heating rates, as also long term steady-state temperatures for annealing and isothermal decay studies. The system operates at a pressure of 1.33 x 10 -3 Pa. Presently it is being used for lithium fluoride low temperature thermoluminescent studies. (author) [pt

  10. Mechanical pumping at low temperature

    International Nuclear Information System (INIS)

    Perin, J.P.; Claudet, G.; Disdier, F.

    1995-01-01

    This novel concept consist of a mechanical pump able to run at low temperature (25K). Since gas density varies inversely with temperature, this pump would deliver much higher mass flow rate than at room temperature for a given size. Advantages of this concept are order of magnitude reduction in size, weight, when compared to a conventional pump scaled to perform the same mass flow rate at room temperature. This pump would be a solution to allow continuously tritium extraction and minimize the mass inventory. (orig.)

  11. Photon propagators at finite temperature

    International Nuclear Information System (INIS)

    Yee, J.H.

    1982-07-01

    We have used the real time formalism to compute the one-loop finite temperature corrections to the photon self energies in spinor and scalar QED. We show that, for a real photon, only the transverse components develop the temperature-dependent masses, while, for an external static electromagnetic field applied to the finite temperature system, only the static electric field is screened by thermal fluctuations. After showing how to compute systematically the imaginary parts of the finite temperature Green functions, we have attempted to give a microscopic interpretation of the imaginary parts of the self energies. (author)

  12. High Temperature Superconductor Resonator Detectors

    Data.gov (United States)

    National Aeronautics and Space Administration — High Temperature Superconductor (HTS) infrared detectors were studied for years but never matured sufficiently for infusion into instruments. Several recent...

  13. Temperature standards, what and where: resources for effective temperature measurements

    International Nuclear Information System (INIS)

    Johnston, W.W. Jr.

    1982-01-01

    Many standards have been published to describe devices, methods, and other topics. How they are developed and by whom are briefly described, and an attempt is made to extract most of those relating to temperature measurements. A directory of temperature standards and their sources is provided

  14. Temperature trends with reduced impact of ocean air temperature

    DEFF Research Database (Denmark)

    Lansner, Frank; Pedersen, Jens Olaf Pepke

    Temperature data 1900-2010 from meteorological stations across the world have been analysed and it has been found that all areas generally have two different valid temperature trends. Coastal stations and hill stations facing dominant ocean winds are normally more warm-trended than the valley sta...

  15. Temperature trends with reduced impact of ocean air temperature

    DEFF Research Database (Denmark)

    Lansner, Frank; Pedersen, Jens Olaf Pepke

    2018-01-01

    Temperature data 1900–2010 from meteorological stations across the world have been analyzed and it has been found that all land areas generally have two different valid temperature trends. Coastal stations and hill stations facing ocean winds are normally more warm-trended than the valley station...

  16. Estimation of complete temperature fields from measured temperatures

    International Nuclear Information System (INIS)

    Clegg, S.T.; Roemer, R.B.

    1984-01-01

    In hyperthermia treatments, it is desirable to be able to predict complete tissue temperature fields from sampled temperatures taken at a few locations. This is a difficult problem in hyperthermia treatments since the tissue blood perfusion is unknown. An initial attempt to do this automatically using unconstrained optimization techniques to minimize the differences between steady state temperatures measured during a treatment and temperatures (at the same locations) predicted from treatment simulations has been previously reported. A second technique using transient temperatures following a step decrease in power has been developed. This technique, which appears to be able to better predict complete temperature fields is presented and both it and the steady state technique are applied to data from both simulated and experimental hyperthermia treatments. The results of applying the two techniques are compared for one-dimensional situations. One particularly important problem which the transient technique can solve (and the steady state technique does not seem to be able to do as well) is that of predicting the complete temperature field in situations where the true maximum and/or minimum temperatures present are not measured by the available instrumentation

  17. Thermodynamic Temperatures of High-Temperature Fixed Points: Uncertainties Due to Temperature Drop and Emissivity

    Science.gov (United States)

    Castro, P.; Machin, G.; Bloembergen, P.; Lowe, D.; Whittam, A.

    2014-07-01

    This study forms part of the European Metrology Research Programme project implementing the New Kelvin to assign thermodynamic temperatures to a selected set of high-temperature fixed points (HTFPs), Cu, Co-C, Pt-C, and Re-C. A realistic thermal model of these HTFPs, developed in finite volume software ANSYS FLUENT, was constructed to quantify the uncertainty associated with the temperature drop across the back wall of the cell. In addition, the widely applied software package, STEEP3 was used to investigate the influence of cell emissivity. The temperature drop, , relates to the temperature difference due to the net loss of heat from the aperture of the cavity between the back wall of the cavity, viewed by the thermometer, defining the radiance temperature, and the solid-liquid interface of the alloy, defining the transition temperature of the HTFP. The actual value of can be used either as a correction (with associated uncertainty) to thermodynamic temperature evaluations of HTFPs, or as an uncertainty contribution to the overall estimated uncertainty. In addition, the effect of a range of furnace temperature profiles on the temperature drop was calculated and found to be negligible for Cu, Co-C, and Pt-C and small only for Re-C. The effective isothermal emissivity is calculated over the wavelength range from 450 nm to 850 nm for different assumed values of surface emissivity. Even when furnace temperature profiles are taken into account, the estimated emissivities change only slightly from the effective isothermal emissivity of the bare cell. These emissivity calculations are used to estimate the uncertainty in the temperature assignment due to the uncertainty in the emissivity of the blackbody.

  18. Fibre-optic temperature sensor

    International Nuclear Information System (INIS)

    Zhao Jie; Liu Zhenyuan.

    1993-04-01

    This experiment is a kind of nonfunction fibre-optic temperature sensor. It utilizes high-sensitive bimetallic strip for element of measuring temperature. The changing of bimetallic strip alterates intensity of light through fibre-optic. This equipment is simple in structure, subtle in design, extensive in application, and so on. (author). 4 refs, 6 figs, 1 tab

  19. Prenatal temperature shocks reduce cooperation

    NARCIS (Netherlands)

    Duchoslav, Jan

    2017-01-01

    Climate change has not only led to a sustained rise in mean global temperature over the past decades, but also increased the frequency of extreme weather events. This paper explores the effect of temperature shocks in utero on later-life taste for cooperation. Using historical climate data combined

  20. Temperature evolution during dissipative collapse

    Indian Academy of Sciences (India)

    Abstract. We investigate the gravitational collapse of a radiating sphere evolving into a final static configuration described by the interior Schwarzschild solution. The temperature profiles of this par- ticular model are obtained within the framework of causal thermodynamics. The overall temperature evolution is enhanced by ...

  1. Certification testing at low temperatures

    International Nuclear Information System (INIS)

    Noss, P.W.; Ammerman, D.J.

    2004-01-01

    Regulations governing the transport of radioactive materials require that most hypothetical accident condition tests or analyses consider the effects of the environmental temperature that most challenges package performance. For many packages, the most challenging temperature environment is the cold condition (-29 C according to U.S. regulations), primarily because the low temperature causes the highest free drop impact forces due to the higher strength of many energy-absorbing materials at this temperature. If it is decided to perform low temperature testing, it is only necessary that the relevant parts of the package have the required temperature prior to the drop. However, the details of performing a drop at low temperature can have a large influence on testing cost and technical effectiveness. The selection of the test site, the chamber and type of chilling equipment, instrumentation, and even the time of year are all important. Control of seemingly minor details such as the effect on internal pressure, placement of monitoring thermocouples, the thermal time constant of the test article, and icing of equipment are necessary to ensure a successful low temperature test. This paper will discuss these issues and offer suggestions based on recent experience

  2. Circadian Pacemaker – Temperature Compensation

    NARCIS (Netherlands)

    Gerkema, Menno P.; Binder, Marc D.; Hirokawa, Nobutaka; Windhorst, Uwe

    2009-01-01

    One of the defining characteristics of circadian pacemakers and indicates the independence of the speed of circadian clock processes of environmental temperature. Mechanisms involved, so far not elucidated in full detail, entail at least two processes that are similarly affected by temperature

  3. HIGH TEMPERATURE POLYMER FUEL CELLS

    DEFF Research Database (Denmark)

    Jensen, Jens Oluf; Qingfeng, Li; He, Ronghuan

    2003-01-01

    This paper will report recent results from our group on polymer fuel cells (PEMFC) based on the temperature resistant polymer polybenzimidazole (PBI), which allow working temperatures up to 200°C. The membrane has a water drag number near zero and need no water management at all. The high working...

  4. CTCP temperature fields and stresses

    Directory of Open Access Journals (Sweden)

    Minjiang Zhang

    2017-11-01

    Full Text Available Cross-tensioned concrete pavements (CTCPs are used in the construction of continuous Portland cement concrete pavements. They eliminate the need for transverse joints and also restrict cracking of the pavement. A CTCP consists of three components, namely, the CTCP slab, the sand sliding layer (SSL, and the cement-stabilized macadam base, from top to down. The retard-bonded tendons (RBTs of the CTCP slab are arranged diagonally. In the present study, a detailed 3D finite element model was developed and used to examine the temperature fields and stresses of a CTCP by thermal-mechanical coupling analysis, and the results were compared with field measurements. The model investigations revealed that, under typical cloudless summer conditions, the temperature field of the CTCP varied nonlinearly with both time and depth. The resultant step-type temperature gradient of the CTCP represents a significant deviation from that of a conventional pavement and impacts the thermal contact resistance of the SSL. It was found that the SSL could effectively reduce the temperature stresses in the CTCP, and that the residual temperature stresses were effectively resisted by the staged cross-tensioned RBTs. The potential problem areas in the vicinity of the temperature stresses were also investigated by the finite element method and field tests. Keywords: Portland cement concrete pavement, Prestressed concrete pavement, Temperature stress, Temperature field, Finite element method, Retard-bonded tendon

  5. The Kelvin and Temperature Measurements

    Science.gov (United States)

    Mangum, B. W.; Furukawa, G. T.; Kreider, K. G.; Meyer, C. W.; Ripple, D. C.; Strouse, G. F.; Tew, W. L.; Moldover, M. R.; Johnson, B. Carol; Yoon, H. W.; Gibson, C. E.; Saunders, R. D.

    2001-01-01

    The International Temperature Scale of 1990 (ITS-90) is defined from 0.65 K upwards to the highest temperature measurable by spectral radiation thermometry, the radiation thermometry being based on the Planck radiation law. When it was developed, the ITS-90 represented thermodynamic temperatures as closely as possible. Part I of this paper describes the realization of contact thermometry up to 1234.93 K, the temperature range in which the ITS-90 is defined in terms of calibration of thermometers at 15 fixed points and vapor pressure/temperature relations which are phase equilibrium states of pure substances. The realization is accomplished by using fixed-point devices, containing samples of the highest available purity, and suitable temperature-controlled environments. All components are constructed to achieve the defining equilibrium states of the samples for the calibration of thermometers. The high quality of the temperature realization and measurements is well documented. Various research efforts are described, including research to improve the uncertainty in thermodynamic temperatures by measuring the velocity of sound in gas up to 800 K, research in applying noise thermometry techniques, and research on thermocouples. Thermometer calibration services and high-purity samples and devices suitable for “on-site” thermometer calibration that are available to the thermometry community are described. Part II of the paper describes the realization of temperature above 1234.93 K for which the ITS-90 is defined in terms of the calibration of spectroradiometers using reference blackbody sources that are at the temperature of the equilibrium liquid-solid phase transition of pure silver, gold, or copper. The realization of temperature from absolute spectral or total radiometry over the temperature range from about 60 K to 3000 K is also described. The dissemination of the temperature scale using radiation thermometry from NIST to the customer is achieved by

  6. Pricing of temperature index insurance

    Directory of Open Access Journals (Sweden)

    Che Mohd Imran Che Taib

    2012-01-01

    Full Text Available The aim of this paper is to study pricing of weather insurance contracts based on temperature indices. Three different pricing methods are analysed: the classical burn approach, index modelling and temperature modelling. We take the data from Malaysia as our empirical case. Our results show that there is a significant difference between the burn and index pricing approaches on one hand, and the temperature modelling method on the other. The latter approach is pricing the insurance contract using a seasonal autoregressive time series model for daily temperature variations, and thus provides a precise probabilistic model for the fine structure of temperature evolution. We complement our pricing analysis by an investigation of the profit/loss distribution from the contract, in the perspective of both the insured and the insurer.

  7. Mechanical pumping at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Perin, J.P.; Claudet, G.; Disdier, F.

    1994-12-31

    This new concept consists of a mechanical pump able to run at low temperature (25 K). Since gas density varies inversely with temperature, the pump could deliver much higher mass flow rate than at room temperature for a given size. Advantages of this concept are reduction of an order of magnitude in size and weight when compared to a conventional pump scaled to perform the same mass flow rate at room temperature. Results obtained at 80 K and 25 K with a Holweck type molecular drag pump of 100 mm diameter and with few stages of a turbomolecular pump running at the same temperatures, are given. This pump would be a solution to allow continuous tritium extraction and minimize the mass inventory for the ITER (International Tokamak Experiment Reactor). 5 figs., 2 tabs., 4 refs.

  8. Effect of ambient temperature on human pain and temperature perception.

    Science.gov (United States)

    Strigo, I A; Carli, F; Bushnell, M C

    2000-03-01

    Animal studies show reduced nociceptive responses to noxious heat stimuli and increases in endogenous beta-endorphin levels in cold environments, suggesting that human pain perception may be dependent on ambient temperature. However, studies of changes in local skin temperature on human pain perception have yielded variable results. This study examines the effect of both warm and cool ambient temperature on the perception of noxious and innocuous mechanical and thermal stimuli. Ten subjects (7 men and 3 women, aged 20-23 yr) used visual analog scales to rate the stimulus intensity, pain intensity, and unpleasantness of thermal (0-50 degrees C) and mechanical (1.2-28.9 g) stimuli applied on the volar forearm with a 1-cm2 contact thermode and von Frey filaments, respectively. Mean skin temperatures were measured throughout the experiment by infrared pyrometer. Each subject was tested in ambient temperatures of 15 degrees C (cool), 25 degrees C (neutral), and 35 degrees C (warm) on separate days, after a 30-min acclimation to the environment. Studies began in the morning after an 8-h fast. Mean skin temperature was altered by ambient temperature (cool room: 30.1 degrees C; neutral room: 33.4 degrees C; warm room: 34.5 degrees C; P cool than in the neutral environment (P cool room and that noxious heat stimuli were more unpleasant in a warm environment. Environmental temperature did not alter ratings of warm (37 and 40 degrees C) or mechanical stimuli. These results indicate that, in humans, a decrease in skin temperature following exposure to cool environments reduces thermal pain. Suppression of Adelta primary afferent cold fiber activity has been shown to increase cold pain produced by skin cooling. Our current findings may represent the reverse phenomenon, i.e., a reduction in thermal nociceptive transmission by the activation of Adelta cutaneous cold fibers.

  9. Deformation, strength and toughness of Al-6xxx profile welds under static and crash loads. Final report; Verformungsfaehigkeit, Festigkeit und Zaehigkeit von AI-6XXX-Profilschweissverbindungen bei statischer und crashartiger Belastung. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Oeser, S.; Memhard, D.; Blauel, J.G.; Boehme

    2000-10-01

    The mechanical behaviour of welded aluminium alloy profiles was characterised using a MIG weld on a die-cast ICE floor profile of AlMgSi0,7/SG-AlMg4,5MnZr, including the material gradients induced by welding and the influence of higher load rates. Mechanical-technological characteristics as well as stress/strain curves of the different zones were measured on small tensile test pieces. The tensile tests were simulated using the Gurson model in order to define parameters for a description of the ductile damage. Using these damage parameters, tensile tests were simulated on flat tensile test pieces with orientation transverse to the weld in order to assess the load, deformation and failure characteristics of the whole (flawless) weld. Flawed seams were tested in experiments with CCT (centre-cracked tensile) test pieces in order to obtain cracking resistance curves J{sub R}. The numerical analyses covered both deformation and failure. [German] Das mechanische Verhalten von geschweissten Profilkonstruktionen aus Aluminiumlegierungen wurde am Beispiel einer MIG-Schweissverbindung an einem stranggepressten ICE-Bodenprofil aus AlMgSi0,7/SG-AlMg4,5MnZr werkstoffmechanisch charakterisiert. Dabei wurden die schweissbedingten Werkstoffgradienten ebenso beruecksichtigt wie der Einfluss hoeherer Belastungsgeschwindigkeiten. Anhand von Versuchen an Kleinzugproben wurden mechanisch-technologische Kennwerte sowie wahre Spannungs-Dehnungs-Kurven fuer die einzelnen Materialbereiche (Grundwerkstoff, Waermeeinflusszone, Schweissgut) ermittelt. Diese Zugversuche wurden mit dem Gurson-Modell simuliert, um Parameter fuer eine Beschreibung der duktilen Schaedigung zu bestimmen. Mit diesen Schaedigungsparametern wurden an Flachzugproben mit Orientierung quer zur Naht durchgefuehrte Zugversuche simuliert, um das Traglast-, Verformungs- und Versagensverhalten der gesamten (fehlerfreien) Naht zu analysieren. Fuer die Charakterisierung des Nahtverhaltens mit Fehler wurden Bruchmechanikversuche an CCT (centre-cracked tensile)-Proben zur Ermittlung von Risswiderstands-J{sub R}-Kurven durchgefuehrt und numerisch ueber Verformung bis zum Versagen simuliert. (orig.)

  10. Temperature oscillations at critical temperature in two-phase flow

    International Nuclear Information System (INIS)

    Brevi, R.; Cumo, M.; Palmieri, A.; Pitimada, D.

    Some experiments on the temperature oscillations, or thermal cycling, which occur with steam-water flow in once-through cooling systems at the critical temperature zone, i.e., when dryout occurs, are described. A theoretical analysis is done on the characteristic frequency of the oscillations, and the parameters upon which the operating characteristics and the physical properties of the fluid depend. Finally, the temperature distribution in the critical zone is analyzed, examining the thermal transitions that occur due to the rapid variations in the coefficient of heat transfer

  11. HIgh Temperature Photocatalysis over Semiconductors

    Science.gov (United States)

    Westrich, Thomas A.

    Due in large part to in prevalence of solar energy, increasing demand of energy production (from all sources), and the uncertain future of petroleum energy feedstocks, solar energy harvesting and other photochemical systems will play a major role in the developing energy market. This dissertation focuses on a novel photochemical reaction process: high temperature photocatalysis (i.e., photocatalysis conducted above ambient temperatures, T ≥ 100°C). The overarching hypothesis of this process is that photo-generated charge carriers are able to constructively participate in thermo-catalytic chemical reactions, thereby increasing catalytic rates at one temperature, or maintaining catalytic rates at lower temperatures. The photocatalytic oxidation of carbon deposits in an operational hydrocarbon reformer is one envisioned application of high temperature photocatalysis. Carbon build-up during hydrocarbon reforming results in catalyst deactivation, in the worst cases, this was shown to happen in a period of minutes with a liquid hydrocarbon. In the presence of steam, oxygen, and above-ambient temperatures, carbonaceous deposits were photocatalytically oxidized over very long periods (t ≥ 24 hours). This initial experiment exemplified the necessity of a fundamental assessment of high temperature photocatalytic activity. Fundamental understanding of the mechanisms that affect photocatalytic activity as a function of temperatures was achieved using an ethylene photocatalytic oxidation probe reaction. Maximum ethylene photocatalytic oxidation rates were observed between 100 °C and 200 °C; the maximum photocatalytic rates were approximately a factor of 2 larger than photocatalytic rates at ambient temperatures. The loss of photocatalytic activity at temperatures above 200 °C is due to a non-radiative multi-phonon recombination mechanism. Further, it was shown that the fundamental rate of recombination (as a function of temperature) can be effectively modeled as a

  12. Temperature uniformity mapping in a high pressure high temperature reactor using a temperature sensitive indicator

    NARCIS (Netherlands)

    Grauwet, T.; Plancken, van der I.; Vervoort, L.; Matser, A.M.; Hendrickx, M.; Loey, van A.

    2011-01-01

    Recently, the first prototype ovomucoid-based pressure–temperature–time indicator (pTTI) for high pressure high temperature (HPHT) processing was described. However, for temperature uniformity mapping of high pressure (HP) vessels under HPHT sterilization conditions, this prototype needs to be

  13. Cooling of high temperature superconductors below 60 K by means of a two-stage cryogenic mixed refrigerant cascade; Kuehlung von Hochtemperatursupraleitern unterhalb von 60 K mittels einer zweistufigen Gemischkaeltekaskade

    Energy Technology Data Exchange (ETDEWEB)

    Kochenburger, T.M. [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). Inst. fuer Technische Thermodynamik und Kaeltetechnik (ITTK); Grohmann, S. [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). Inst. fuer Technische Thermodynamik und Kaeltetechnik (ITTK); Karlsruher Institut fuer Technologie (KIT), Eggenstein-Leopoldshafen (Germany). Inst. fuer Technische Physik (ITEP)

    2015-07-01

    High temperature superconductors enable the efficient transmission of electrical energy in urban and industrial networks. It is the availability of simple, reliable and at the same time efficient cooling methods prerequisite for the application of this technology. At operating temperatures 65-80 K is the cooling currently mostly implemented by liquid nitrogen, large-scale turbo-Brayton plants or batteries of regenerative cryocooler; however, all these options for applications in the range of a few kW of required cooling capacity have thermodynamic, economic and practical limitations. In addition, a further lowering the cooling temperature below 60 K is desirable to increase the current density in the superconductors. Two-stage cryogenic mixed refrigerant cascade offer the potential for a reliable and easily scalable alternative for refrigeration in this temperature range. The first stage of the considered process consists of a classic mixture refrigeration cycle to pre-cool to 120 K. The second stage operates in the low temperature range up to 55 K with a mixture of nitrogen, oxygen and neon at high pressures. This paper compares on the basis of experimental data, the performance of combustible and non-combustible mixtures in the precooling level. The applicability of various equations of state for modeling of phase behavior of mixtures is discussed. [German] Hochtemperatursupraleiter ermoeglichen den effizienten Transport elektrischer Energie in urbanen und industriellen Netzen. Dabei ist die Verfuegbarkeit von einfachen, zuverlaessigen und gleichzeitig effizienten Kuehlmethoden Voraussetzung fuer die Anwendung dieser Technologie. Bei Betriebstemperaturen von 65 - 80 K wird die Kuehlung derzeit meist durch Fluessigstickstoff, grossskalige Turbo-Brayton-Anlagen oder Batterien regenerativer Kleinkuehler realisiert; jedoch haben alle diese Optionen fuer Anwendungen im Bereich von einigen kW an erforderlicher Kaelteleistung thermodynamische, oekonomische und

  14. Dinosaur fossils predict body temperatures.

    Directory of Open Access Journals (Sweden)

    James F Gillooly

    2006-07-01

    Full Text Available Perhaps the greatest mystery surrounding dinosaurs concerns whether they were endotherms, ectotherms, or some unique intermediate form. Here we present a model that yields estimates of dinosaur body temperature based on ontogenetic growth trajectories obtained from fossil bones. The model predicts that dinosaur body temperatures increased with body mass from approximately 25 degrees C at 12 kg to approximately 41 degrees C at 13,000 kg. The model also successfully predicts observed increases in body temperature with body mass for extant crocodiles. These results provide direct evidence that dinosaurs were reptiles that exhibited inertial homeothermy.

  15. Particle energy and Hawking temperature

    International Nuclear Information System (INIS)

    Ding Chikun; Wang Mengjie; Jing Jiliang

    2009-01-01

    Some authors have recently found that the tunneling approach gives a different Hawking temperature for a Schwarzschild black hole in a different coordinate system. In this Letter, we find that to work out the Hawking temperature in a different coordinate system by the tunneling approach, we must use the correct definition of the energy of the radiating particles. By using a new definition of the particle energy, we obtain the correct Hawking temperature for a Schwarzschild black hole in two dynamic coordinate systems, the Kruskal-Szekers and dynamic Lemaitre coordinate systems.

  16. Temperature Gradient in Hall Thrusters

    International Nuclear Information System (INIS)

    Staack, D.; Raitses, Y.; Fisch, N.J.

    2003-01-01

    Plasma potentials and electron temperatures were deduced from emissive and cold floating probe measurements in a 2 kW Hall thruster, operated in the discharge voltage range of 200-400 V. An almost linear dependence of the electron temperature on the plasma potential was observed in the acceleration region of the thruster both inside and outside the thruster. This result calls into question whether secondary electron emission from the ceramic channel walls plays a significant role in electron energy balance. The proportionality factor between the axial electron temperature gradient and the electric field is significantly smaller than might be expected by models employing Ohmic heating of electrons

  17. Advanced High Temperature Structural Seals

    Science.gov (United States)

    Newquist, Charles W.; Verzemnieks, Juris; Keller, Peter C.; Rorabaugh, Michael; Shorey, Mark

    2002-10-01

    This program addresses the development of high temperature structural seals for control surfaces for a new generation of small reusable launch vehicles. Successful development will contribute significantly to the mission goal of reducing launch cost for small, 200 to 300 pound payloads. Development of high temperature seals is mission enabling. For instance, ineffective control surface seals can result in high temperature (3100 F) flows in the elevon area exceeding structural material limits. Longer sealing life will allow use for many missions before replacement, contributing to the reduction of hardware, operation and launch costs.

  18. Temperature stabilization of injection lasers

    International Nuclear Information System (INIS)

    Albanese, A.

    1987-01-01

    Apparatus which stabilizes the temperature, and thereby the output wavelength, of an injection laser. Means monitor the laser terminal voltage across a laser and derive a voltage therefrom which is proportional to the junction voltage of the laser. Means compares the voltage to a reference value from source and a temperature controller adjusts the laser temperature in response to the results of the comparison. Further embodiments of the present invention vary the output wavelength of the laser by varying the reference value from source against which the laser junction voltage is compared. (author)

  19. Temperature dependence of Brewster's angle.

    Science.gov (United States)

    Guo, Wei

    2018-01-01

    In this work, a dielectric at a finite temperature is modeled as an ensemble of identical atoms moving randomly around where they are trapped. Light reflection from the dielectric is then discussed in terms of atomic radiation. Specific calculation demonstrates that because of the atoms' thermal motion, Brewster's angle is, in principle, temperature-dependent, and the dependence is weak in the low-temperature limit. What is also found is that the Brewster's angle is nothing but a result of destructive superposition of electromagnetic radiation from the atoms.

  20. The Microwave Temperature Profiler (PERF)

    Science.gov (United States)

    Lim, Boon; Mahoney, Michael; Haggerty, Julie; Denning, Richard

    2013-01-01

    The JPL developed Microwave Temperature Profiler (MTP) has recently participated in GloPac, HIPPO (I to V) and TORERO, and the ongoing ATTREX campaigns. The MTP is now capable of supporting the NASA Global Hawk and a new canister version supports the NCAR G-V. The primary product from the MTP is remote measurements of the atmospheric temperature at, above and below the flight path, providing for the vertical state of the atmosphere. The NCAR-MTP has demonstrated unprecedented instrument performance and calibration with plus or minus 0.2 degrees Kelvin flight level temperature error. Derived products include curtain plots, isentropes, lapse rate, cold point height and tropopause height.

  1. High temperature divertor plasma operation

    International Nuclear Information System (INIS)

    Ohyabu, Nobuyoshi.

    1991-02-01

    High temperature divertor plasma operation has been proposed, which is expected to enhance the core energy confinement and eliminates the heat removal problem. In this approach, the heat flux is guided through divertor channel to a remote area with a large target surface, resulting in low heat load on the target plate. This allows pumping of the particles escaping from the core and hence maintaining of the high divertor temperature, which is comparable to the core temperature. The energy confinement is then determined by the diffusion coefficient of the core plasma, which has been observed to be much lower than the thermal diffusivity. (author)

  2. Amorphisation during elevated temperature implantation

    International Nuclear Information System (INIS)

    Carter, G.; Nobes, M.J.; Elliman, R.G.

    1994-01-01

    Transition state theory is employed to predict the rates of amorphous zone recrystallization by direct thermal and radiation mediated thermal annealing processes. These rates are functions of zone radius and are employed to describe the competition between amorphous zone generation and annealing during elevated temperature heavy ion implantation of, particularly, Si and the accumulation of amorphousness with increasing ion fluence. This analysis predicts a change from monotonic to sigmoidal to biexponential accumulation functions with increasing annealing rate or substrate temperature in agreement with experiments. A logarithmic dependence of ion flux density upon substrate temperature for the achievement of defined fractional amorphisation is predicted and is also in agreement with the experiment. (author)

  3. Temperature expansions for magnetic systems

    International Nuclear Information System (INIS)

    Cangemi, D.; Dunne, G.

    1996-01-01

    We derive finite temperature expansions for relativistic fermion systems in the presence of background magnetic fields, and with nonzero chemical potential. We use the imaginary-time formalism for the finite temperature effects, the proper-time method for the background field effects, and zeta function regularization for developing the expansions. We emphasize the essential difference between even and odd dimensions, focusing on 2+1 and 3+1 dimensions. We concentrate on the high temperature limit, but we also discuss the T=0 limit with nonzero chemical potential. Copyright copyright 1996 Academic Press, Inc

  4. High temperature thermoelectric energy conversion

    International Nuclear Information System (INIS)

    Wood, C.

    1986-01-01

    Considerable advances were made in the late '50's and early early '60's in the theory and development of materials for high-temperature thermoelectric energy conversion. This early work culminated in a variety of materials, spanning a range of temperatures, with the product of the figure of merit, Z, and temperature, T, i.e., the dimensionless figure of merit, ZT, of the order of one. This experimental limitation appeared to be universal and led a number of investigators to explore the possibility that a ZT - also represents a theoretical limitation. It was found not to be so

  5. Dual vehicle - Development, construction and testing of a dual vehicle for passenger transport on roads and railways. Final report; Zweiwegefahrzeug - Entwicklung, Bau und Erprobung eines Zweiwegefahrzeuges zur Personenbefoerderung Strasse/Schiene. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This feasibility study investigated a prototype dual vehicle for railways and roads. Technical problems, acceptance specifications, legal and economic aspects were gone into. [German] Zielstellung fuer das Vorhaben war die Untersuchung ausgewaehlter technischer Fragestellungen hinsichtlich der Machbarkeit der Entwicklung und Erprobung eines Prototypes fuer ein Zweiwegefahrzeug fuer den Personenverkehr, das fuer den Einsatz auf der Schiene und der Strasse vorgesehen und dafuer entsprechend technisch ausgestattet ist. Damit erbringt das Vorhaben technisch-konstruktive Loesungsansaetze fuer ein vollstaendig neues Fahrzeuggrundkonzept und traegt hinsichtlich eines solchen zukuenftigen Fahrzeugtyps - zur Klaerung technischer Fragen (statische Zusammenbauuntersuchungen, geometrische und massliche Bedingungen sowie Konzipierung, Leistungsanforderungen der Komponenten, Konzept fuer Ein- und Ausspuren sowie fuer Ein- und Ausstieg), - zur Pruefung der technischen Zulassungsfaehigkeit des Fahrzeuges, - zur Klaerung von Rechtsfragen fuer die Sicherung des Betriebes des Fahrzeuges - sowie zum Nachweis des wirtschaftlicheren Betriebes des Fahrzeuges bei. Das Vorhaben unterbreitet unter Beruecksichtigung sicherheitstechnischer, gesetzlicher und wirtschaftlicher Rahmenbedingungen Loesungsvorschlaege fuer die konstruktive Konzipierung des Fahrgestells und ein technisches Konzept fuer das Ein- und Ausspuren fuer einen neuen Fahrzeugtyp, der sowohl fuer die Strassenbenutzung als auch fuer den Schienenverkehr zugelassen ist. (orig.)

  6. Investigations into the use of bacteria for enhanced recovery of petroleum; Untersuchungen zum Einsatz von Bakterien zur Erhoehung des Entoelungsgrades in Erdoellagerstaetten

    Energy Technology Data Exchange (ETDEWEB)

    Amro, M.

    1995-06-01

    Strains of bacteria were investigated with a view to their applicability and efficiency in enhanced recovery of petroleum. The mechanisms of enhanced recovery with bacteria were to be clarified as well. The experiments were carried out as static autoclave experiments without bedrock and as dynamic flooding experiments in a model pore space (Bentheim sandstone and carbonate rock) under the conditions of North German petroleum deposits. The static experiments carried out preliminary to the more time-consuming dynamic flooding experiments were to help with an optimized design of the injection experiments. (orig.) [Deutsch] Die vorliegende Arbeit hat zum Ziel, entoelungswirksame Bakterienstaemme zu untersuchen und hinsichtlich der durch sie bewirkten Erhoehung des Entoelungsgrades zu bewerten. Gleichzeitig sollen die Mechanismen aufgeklaert werden, die der Entoelungsverbesserung durch Einsatz von Bakterien zugrunde liegen. Die Experimente wurden als statische Autoklavenversuche ohne Lagerstaettengestein sowie als dynamische Flutversuche im Modellporenraum (Bentheimer Sandstein und karbonatisches Gesteinsmaterial) unter Bedingungen norddeutscher Lagerstaetten durchgefuehrt. Die statischen Versuche, die als Auswahltests den aufwendigeren dynamischen Flutversuchen vorgeschaltet waren, sollten dazu beitragen, die Flutversuche gezielt konzipieren zu koennen. (orig./EF)

  7. Refrigeration systems of high temperature superconduction transformers for rail vehicles. Final report; Kaelteversorgung von Schienenfahrzeug-Transformatoren mit HT-Supraleitung. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Glatthaar, R.

    2000-09-01

    The refrigeration system for the HTS-transformer was designed in cooperation with the transformer manufacturer and the requirements for the refrigerator have been determined. Several active and passive refrigeration systems were investigated, two of them have been elaborated more detailed. All the refrigeration systems are based on the concept of a liquid nitrogen flow rate of 1000 g/s passing through the 6 MVA transformer at a temperature of approx. 66 K and at a pressure of approx. 3 bars. The passive system uses as refrigerant source a tank with liquid nitrogen, weighing approx. 2300 kg and consuming 500 kg liquid nitrogen per day. After evaporating and preheating the nitrogen used exits to atmosphere with a vacuum pump. The active system elaborated more detailed applies a Stirling engine for refrigeration, will weigh 1600 kg and needs an average electric power of 25 kW. The refrigeration system for a transformer of ceramic superconducting material has significant advantages with regard to weight, power consumption and investment costs compared to a transformer of the same size manufactured as metallic superconductors. (orig.) [German] In Zusammenarbeit mit dem Transformatorhersteller wurden die Kaelteversorgung des HTS-Transformators konzipiert und die Anforderungen an die Kaelteanlage festgelegt. Verschiedene sogenannte passive und aktive Systeme fuer die Kaelteversorgung wurden untersucht, zwei davon naeher ausgearbeitet. Die Kuehlkonzepte sehen vor, dass fuer einen Transformator der Leistung 6 MVA ein Strom an fluessigem Stickstoff von 1000 g/s mit einer Temperatur von ca. 66 K und unter einem Druck von rund 3 bar durch den Transformator geleitet wird. Das passive System ist gekennzeichnet durch Einsatz eines Tanks fuer fluessigen Stickstoff als Kaeltequelle, hat ein Gewicht von etwa 2300 kg und einen Verbrauch an fluessigem Stickstoff von 500 kg/Tag. Der Stickstoff wird nach Verdampfung und Anwaermung mit Hilfe einer Vakuumpumpe an die Umgebung abgegeben

  8. Highly efficient high temperature electrolysis

    DEFF Research Database (Denmark)

    Hauch, Anne; Ebbesen, Sune; Jensen, Søren Højgaard

    2008-01-01

    High temperature electrolysis of water and steam may provide an efficient, cost effective and environmentally friendly production of H-2 Using electricity produced from sustainable, non-fossil energy sources. To achieve cost competitive electrolysis cells that are both high performing i.e. minimum...... internal resistance of the cell, and long-term stable, it is critical to develop electrode materials that are optimal for steam electrolysis. In this article electrolysis cells for electrolysis of water or steam at temperatures above 200 degrees C for production of H-2 are reviewed. High temperature...... electrolysis is favourable from a thermodynamic point of view, because a part of the required energy can be supplied as thermal heat, and the activation barrier is lowered increasing the H-2 production rate. Only two types of cells operating at high temperature (above 200 degrees C) have been described...

  9. ISLSCP II Sea Surface Temperature

    Data.gov (United States)

    National Aeronautics and Space Administration — Sea surface temperature (SST) is an important indicator of the state of the earth climate system as well as a key variable in the coupling between the atmosphere and...

  10. World Ocean Atlas 2005, Temperature

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Ocean Atlas 2005 (WOA05) is a set of objectively analyzed (1° grid) climatological fields of in situ temperature, salinity, dissolved oxygen, Apparent Oxygen...

  11. TEMPERATURE TOLERANCES AND OSMOREGULATION IN ...

    African Journals Online (AJOL)

    The salinity and temperature tolerances of some burrowiq bivalves which oc:eur ... Along most of the estuary the salinity normally remains close to that of seawater (35'/.) ...... grapsoid crabs, Hemigrapsus nudus and Hemigrapsus oregonensis.

  12. Photoirradiation system with temperature control

    International Nuclear Information System (INIS)

    Yonadab Lopez, F.; Stolik, S.; La Rosa, J. M. de; Moreno, E.

    2012-01-01

    During application of phototherapy is possible to induce a significant increase in tissue temperature and generate a localized hyperthermia state if the power density of incident light is high enough. We present a controlled temperature phototherapy system, this allows the application of optical radiation at a wavelength of 630nm using a light emitting diode (LED) of high power. The system automatically controls the irradiation time and power which allows irradiating the tissue with an appropriate energy density. A thermocouple is placed in the irradiated tissue to measure and control the temperature by varying the parameters of power density and time. From results of irradiations made in nu / nu mice using doses of 150 J/cm 2 energy and 250 J/cm 2 shows that the temperature control allows the study of photodynamic therapy in synergy with thermo therapy in different diseases external tissues. (Author)

  13. High temperature creep of vanadium

    International Nuclear Information System (INIS)

    Juhasz, A.; Kovacs, I.

    1978-01-01

    The creep behaviour of polycrystalline vanadium of 99.7% purity has been investigated in the temperature range 790-880 0 C in a high temperature microscope. It was found that the creep properties depend strongly on the history of the sample. To take this fact into account some additional properties such as the dependence of the yield stress and the microhardness on the pre-annealing treatment have also been studied. Samples used in creep measurements were selected on the basis of their microhardness. The activation energy of creep depends on the microhardness and on the creep temperature. In samples annealed at 1250 0 C for one hour (HV=160 kgf mm -2 ) the rate of creep is controlled by vacancy diffusion in the temperature range 820-880 0 C with an activation energy of 78+-8 kcal mol -1 . (Auth.)

  14. RPC operation at high temperature

    CERN Document Server

    Aielli, G; Cardarelli, R; Di Ciaccio, A; Di Stante, L; Liberti, B; Paoloni, A; Pastori, E; Santonico, R

    2003-01-01

    The resistive electrodes of RPCs utilised in several current experiments (ATLAS, CMS, ALICE, BABAR and ARGO) are made of phenolic /melaminic polymers, with room temperature resistivities ranging from 10**1**0 Omega cm, for high rate operation in avalanche mode, to 5 multiplied by 10**1**1 Omega cm, for streamer mode operation at low rate. The resistivity has however a strong temperature dependence, decreasing exponentially with increasing temperature. We have tested several RPCs with different electrode resistivities in avalanche as well as in streamer mode operation. The behaviours of the operating current and of the counting rate have been studied at different temperatures. Long-term operation has also been studied at T = 45 degree C and 35 degree C, respectively, for high and low resistivity electrodes RPCs.

  15. Temperature imaging using epithermal neutrons

    International Nuclear Information System (INIS)

    Fowler, P.H.; Taylor, A.D.

    1987-08-01

    The paper concerns the temperature measurement of suitable targets, both remotely and non-invasively, using epithermal neutrons. The text was presented at the Neutron Resonance Radiography Workshop, Los Alamos, U.S.A., 1987. The technique is demonstrated for tantalum foils at different temperatures, using a pulsed beam of epithermal neutrons, at both Los Alamos and ISIS (United Kingdom). Results on the measured time-of-flight spectra and the tantalum resonances are presented. Beam properties and fluxes at ISIS are discussed. Features of the proposed detectors suitable for the temperature technique are outlined, along with the data analysis, the moving targets, the cyclic temperature variations and transients, and the usefulness of the technique. (U.K.)

  16. Environmental Radioactivity, Temperature, and Precipitation.

    Science.gov (United States)

    Riland, Carson A.

    1996-01-01

    Reports that environmental radioactivity levels vary with temperature and precipitation and these effects are due to radon. Discusses the measurement of this environmental radioactivity and the theory behind it. (JRH)

  17. Temperature dependence of plastic scintillators

    Science.gov (United States)

    Peralta, L.

    2018-03-01

    Plastic scintillator detectors have been studied as dosimeters, since they provide a cost-effective alternative to conventional ionization chambers. Several articles have reported undesired response dependencies on beam energy and temperature, which provides the motivation to determine appropriate correction factors. In this work, we studied the light yield temperature dependency of four plastic scintillators, BCF-10, BCF-60, BC-404, RP-200A and two clear fibers, BCF-98 and SK-80. Measurements were made using a 50 kVp X-ray beam to produce the scintillation and/or radioluminescence signal. The 0 to 40 °C temperature range was scanned for each scintillator, and temperature coefficients were obtained.

  18. High Temperature Materials Laboratory (HTML)

    Data.gov (United States)

    Federal Laboratory Consortium — The six user centers in the High Temperature Materials Laboratory (HTML), a DOE User Facility, are dedicated to solving materials problems that limit the efficiency...

  19. Temperature profiles of coal stockpiles

    Energy Technology Data Exchange (ETDEWEB)

    Sensogut, C.; Ozdeniz, A.H.; Gundogdu, I.B. [Dumlupinar University, Kutahya (Turkey). Mining Engineering Department

    2008-07-01

    Excess of produced coals should be kept in the stockyards of the collieries. The longer the duration time for these coals, the greater possibility for spontaneous combustion to take place. Spontaneously burnt coals result in economical and environmental problems. Therefore, taking the necessary precautions before an outburst of the spontaneous combustion phenomenon is too important in terms of its severe results. In this study, a stockpile having industrial dimensions was formed in coal stockyard. The effective parameters on the stockpiles of coal such as temperature and humidity of the weather, time, and atmospheric pressure values were measured. The interior temperature variations of these stockpiles caused by the atmospheric conditions were also measured. The interior temperature distribution maps of the stockpile together with maximum and minimum temperature values were expressed visually and numerically by the assistance of obtained data.

  20. Temperature controller of semiconductor laser

    Czech Academy of Sciences Publication Activity Database

    Matoušek, Vít; Číp, Ondřej

    2003-01-01

    Roč. 73, č. 3 (2003), s. 10 - 12 ISSN 0928-5008 Institutional research plan: CEZ:AV0Z2065902 Keywords : temperature controller * semiconductor laser * laser diode Subject RIV: BH - Optics, Masers, Lasers

  1. Fuel Temperature Coefficient of Reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Loewe, W.E.

    2001-07-31

    A method for measuring the fuel temperature coefficient of reactivity in a heterogeneous nuclear reactor is presented. The method, which is used during normal operation, requires that calibrated control rods be oscillated in a special way at a high reactor power level. The value of the fuel temperature coefficient of reactivity is found from the measured flux responses to these oscillations. Application of the method in a Savannah River reactor charged with natural uranium is discussed.

  2. Cepheid radii and effective temperatures

    International Nuclear Information System (INIS)

    Fernley, J.A.; Skillen, I.; Jameson, R.F.

    1989-01-01

    New infrared photometry for the Cepheid variables T Vul, δ Cephei and XCyg is presented. Combining this with published infrared photometry of T Vul, ηAql, S Sge and XCyg and published optical photometry we use the infrared flux method to determine effective temperatures and angular radii at all phases of the pulsation cycle. These angular radii combined with published radial velocity curves then give the radii of the stars. Knowing the radii and effective temperatures we obtain the absolute magnitudes. (author)

  3. Morphology and Temperatures at Pele

    Science.gov (United States)

    Howell, Robert R.; Lopes, R. M. C.

    2010-10-01

    The Pele region of Io has been the site of vigorous volcanic activity from the time of the first Voyager I observations in 1979 up through the final Galileo ones in 2001. There is high temperature thermal emission from what is thought to be a rapidly overturning lava lake, and also the source of a large sulfur-rich plume. We present a new analysis of Voyager I visible wavelength images, and Galileo Solid State Imager (SSI) and Near Infrared Mapping Spectrometer (NIMS) thermal emission observations which better define the morphology of the region and the intensity of the emission. The observations show remarkably correlations between the locations of the emission and the features seen in the Voyager images, which provide insight into eruption mechanisms and constrain the longevity of the activity. We also analyze an additional wavelength channel of NIMS data (1.87 micron) which paradoxically, because of reduced sensitivity, allows us to estimate temperatures at the peak locations of emission. Measurements of eruption temperatures on Io are crucial because they provide our best clues to the composition of the magma. High color temperatures indicative of ultramafic composition have been reported for the Pillan hot spot and possibly for Pele, although recent work has called into question the requirement for magma temperatures above those expected for ordinary basalts. Our new analysis of the Pele emission near the peak of the hot spot shows color temperatures near the upper end of the basalt range during the I27 and I32 encounters. We also analyze those temperatures in terms of lava cooling models to determine the required magma temperatures.

  4. Ion temperature profiles in JET

    International Nuclear Information System (INIS)

    Hellermann, M. von; Mandl, W.; Summers, H.P.; Weisen, H.

    1989-01-01

    The results presented in this paper have shown some extreme cases of ion temperature profiles illustrating the different operation modes of the JET tokamak. In the three examples of low-density high temperature, high-density moderates and high-density high-confinement plasmas comparable values of a maximum fusion product n d T i τ E in the order of 10 20 keV m -3 sec are achieved. (author) 1 ref., 7 figs

  5. Physics behind the Debye temperature

    OpenAIRE

    Garai, Jozsef

    2007-01-01

    Textbooks introduce the Debye temperature to simplify the integration of the heat capacity. This approach gives the impression that the Debye temperature is a parameter which makes the integration more convenient. The Debye frequency cut occurs when the wavelength of the phonon frequency reaches the size of the smallest unit of the lattice which is the length of the unit cell. At frequencies higher than the cut off frequency the 'lattice' unable to 'see' the vibration because the wavelength o...

  6. Parameterizing the interstellar dust temperature

    Science.gov (United States)

    Hocuk, S.; Szűcs, L.; Caselli, P.; Cazaux, S.; Spaans, M.; Esplugues, G. B.

    2017-08-01

    The temperature of interstellar dust particles is of great importance to astronomers. It plays a crucial role in the thermodynamics of interstellar clouds, because of the gas-dust collisional coupling. It is also a key parameter in astrochemical studies that governs the rate at which molecules form on dust. In 3D (magneto)hydrodynamic simulations often a simple expression for the dust temperature is adopted, because of computational constraints, while astrochemical modelers tend to keep the dust temperature constant over a large range of parameter space. Our aim is to provide an easy-to-use parametric expression for the dust temperature as a function of visual extinction (AV) and to shed light on the critical dependencies of the dust temperature on the grain composition. We obtain an expression for the dust temperature by semi-analytically solving the dust thermal balance for different types of grains and compare to a collection of recent observational measurements. We also explore the effect of ices on the dust temperature. Our results show that a mixed carbonaceous-silicate type dust with a high carbon volume fraction matches the observations best. We find that ice formation allows the dust to be warmer by up to 15% at high optical depths (AV> 20 mag) in the interstellar medium. Our parametric expression for the dust temperature is presented as Td = [ 11 + 5.7 × tanh(0.61 - log 10(AV) ]χuv1/5.9, where χuv is in units of the Draine (1978, ApJS, 36, 595) UV field.

  7. Michelson interferometer for measuring temperature

    OpenAIRE

    Xie, Dong; Xu, Chunling; wang, Anmin

    2016-01-01

    We investigate that temperature can be measured by a modified Michelson interferometer, where at least one reflected mirror is replaced by a thermalized sample. Both of two mirrors replaced by the corresponding two thermalized samples can help to approximatively improve the resolution of temperature up to twice than only one mirror replaced by a thermalized sample. For further improving the precision, a nonlinear medium can be employed. The Michelson interferometer is embedded in a gas displa...

  8. Quantum Chromodynamic at finite temperature

    International Nuclear Information System (INIS)

    Magalhaes, N.S.

    1987-01-01

    A formal expression to the Gibbs free energy of topological defects of quantum chromodynamics (QCD)by using the semiclassical approach in the context of field theory at finite temperature and in the high temperature limit is determined. This expression is used to calculate the free energy of magnetic monopoles. Applying the obtained results to a method in which the free energy of topological defects of a theory may indicate its different phases, its searched for informations about phases of QCD. (author) [pt

  9. Perturbative QCD at finite temperature

    International Nuclear Information System (INIS)

    Altherr, T.

    1989-03-01

    We discuss an application of finite temperature QCD to lepton-pair production in a quark-gluon plasma. The perturbative calculation is performed within the realtime formalism. After cancellation of infrared and mass singularities, the corrections at O (α s ) are found to be very small in the region where the mass of the Drell-Yan pair is much larger than the temperature of the plasma. Interesting effects, however, appear at the annihilation threshold of the thermalized quarks

  10. Temperature radiation measuring equipment. Temperaturstrahlungsmessgeraet

    Energy Technology Data Exchange (ETDEWEB)

    Lotzer, W

    1981-01-22

    The invention is concerned with a temperature radiation measuring equipment for non-contact temperature measurement by the light intensity variation method, with a photoelectric resistance as the measuring element. By having a circuit with a transistor, the 'dark resistance' occurring in the course of time is compensated for and thus gives a genuine reading (ie. the voltage drop across the photoelectric resistance remains constant).

  11. Spinor pregeometry at finite temperature

    International Nuclear Information System (INIS)

    Yoshimoto, Seiji.

    1985-10-01

    We derive the effective action for gravity at finite temperature in spinor pregeometry. The temperature-dependent effective potential for the vierbein which is parametrized as e sub(kμ) = b.diag(1, xi, xi, xi) has the minimum at b = 0 for fixed xi, and behaves as -xi 3 for fixed b. These results indicate that the system of fundamental matters in spinor pregeometry cannot be in equilibrium. (author)

  12. Bentonite Permeability at Elevated Temperature

    Directory of Open Access Journals (Sweden)

    Katherine A. Daniels

    2017-01-01

    Full Text Available Repository designs frequently favour geological disposal of radioactive waste with a backfill material occupying void space around the waste. The backfill material must tolerate the high temperatures produced by decaying radioactive waste to prevent its failure or degradation, leading to increased hydraulic conductivity and reduced sealing performance. The results of four experiments investigating the effect of temperature on the permeability of a bentonite backfill are presented. Bentonite is a clay commonly proposed as the backfill in repository designs because of its high swelling capacity and very low permeability. The experiments were conducted in two sets of purpose-built, temperature controlled apparatus, designed to simulate isotropic pressure and constant volume conditions within the testing range of 4–6 MPa average effective stress. The response of bentonite during thermal loading at temperatures up to 200 °C was investigated, extending the previously considered temperature range. The results provide details of bentonite’s intrinsic permeability, total stress, swelling pressure and porewater pressure during thermal cycles. We find that bentonite’s hydraulic properties are sensitive to thermal loading and the type of imposed boundary condition. However, the permeability change is not large and can mostly be accounted for by water viscosity changes. Thus, under 150 °C, temperature has a minimal impact on bentonite’s hydraulic permeability.

  13. Temperature Map of Tempel 1

    Science.gov (United States)

    2005-01-01

    A temperature map of the nucleus with different spatial resolutions. The context image (in black and white) is a HRIVIS image taken just before impact. The color bar in the middle gives temperature in Kelvins. The sun is to the right in all images. These data were acquired with the IR spectrometer using signal between 1.8 and 2.2 um and modeled to contain both a reflected and an emitted component. After this model is applied, the resulting number is a temperature which is represented by different colors with red being the highest and purple the coldest. The derived temperature varies from 260 +/- 6K to 329 +/- 8K. Shadows are the coolest temperatures, and the point directly below the sun is hottest. These temperatures indicate that the thermal inertia of the surface (the quality of the surface describing the ability to conduct and store heat) is low. In other words, on Tempel 1, it is hot in the sun and cold in the shadows. A value for thermal inertia is estimated at 2/s1/2.

  14. High temperature thermometric phosphors for use in a temperature sensor

    Science.gov (United States)

    Allison, Stephen W.; Cates, Michael R.; Boatner, Lynn A.; Gillies, George T.

    1998-01-01

    A high temperature phosphor consists essentially of a material having the general formula LuPO.sub.4 :Dy.sub.(x),Eu.sub.(y), wherein: 0.1 wt %.ltoreq.x.ltoreq.20 wt % and 0.1 wt %.ltoreq.y.ltoreq.20 wt %. The high temperature phosphor is in contact with an article whose temperature is to be determined. The article having the phosphor in contact with it is placed in the environment for which the temperature of the article is to be determined. The phosphor is excited by a laser causing the phosphor to fluoresce. The emission from the phosphor is optically focused into a beam-splitting mirror which separates the emission into two separate emissions, the emission caused by the dysprosium dopant and the emission caused by the europium dopent. The separated emissions are optically filtered and the intensities of the emission are detected and measured. The ratio of the intensity of each emission is determined and the temperature of the article is calculated from the ratio of the intensities of the separate emissions.

  15. Mechanical property tests in hot gas environment for evaluation of life expectancy of aero-engine turbine blades and for assessment of procedures for prolonging service life. Mechanische Pruefung unter Heissgasatmosphaere zur Ermittlung der Lebenserwartung von Fluggasturbinenschaufeln und zur Bewertung von Verfahren zur Lebensdauerverlaengerung

    Energy Technology Data Exchange (ETDEWEB)

    Peichl, L

    1984-01-01

    The aim of this programme was the determination and optimization of mechanical testing procedures in order to enable a service life prediction for turbine blades as well as to measure the life consumption of blades which have already been in service. Under these testing conditions procedures were to be investigated which lead to a prolongation of the service life of the blades. The results have shown that the rig test at constant values of load and temperature, which are typical for service conditions, is sufficient for the laboratory simulation. The life consumption of blades run in the engine can be determined by measuring the residual creep life in the rig test. Using the resulting data the life consumption of a particular blade run in the engine can be estimated by the non-destructive measurement of its elongation. The precision of residual life prediction is raised by respecting the master heat and porosity of the blades. From the investigation of high-temperature corrosion resistant coatings it follows that IN 100 can be protected against the attack of sea salt over its whole creep life by coating with a precious metal modified aluminide or by LPPS- or EB-PVD-MCrAlY-coatings. By aluminising, the cooling channels of turbine blades can be protected against oxidation over more than 700 h in the temperature/load cycling test. However, the coating technique used is only applicable under laboratory conditions. In contrary, internal coating by pulse aluminising, which is compatible to production conditions, showed less oxidation resistance.

  16. Low to moderate temperature nanolaminate heater

    Science.gov (United States)

    Eckels, J Del [Livermore, CA; Nunes, Peter J [Danville, CA; Simpson, Randall L [Livermore, CA; Hau-Riege, Stefan [Fremont, CA; Walton, Chris [Oakland, CA; Carter, J Chance [Livermore, CA; Reynolds, John G [San Ramon, CA

    2011-01-11

    A low to moderate temperature heat source comprising a high temperature energy source modified to output low to moderate temperatures wherein the high temperature energy source modified to output low to moderate temperatures is positioned between two thin pieces to form a close contact sheath. In one embodiment the high temperature energy source modified to output low to moderate temperatures is a nanolaminate multilayer foil of reactive materials that produces a heating level of less than 200.degree. C.

  17. Biophysical control of leaf temperature

    Science.gov (United States)

    Dong, N.; Prentice, I. C.; Wright, I. J.

    2014-12-01

    In principle sunlit leaves can maintain their temperatures within a narrower range than ambient temperatures. This is an important and long-known (but now overlooked) prediction of energy balance theory. Net radiation at leaf surface in steady state (which is reached rapidly) must be equal to the combination of sensible and latent heat exchanges with surrounding air, the former being proportional to leaf-to-air temperature difference (ΔT), the latter to the transpiration rate. We present field measurements of ΔT which confirm the existence of a 'crossover temperature' in the 25-30˚C range for species in a tropical savanna and a tropical rainforest environment. This finding is consistent with a simple representation of transpiration as a function of net radiation and temperature (Priestley-Taylor relationship) assuming an entrainment factor (ω) somewhat greater than the canonical value of 0.26. The fact that leaves in tropical forests are typically cooler than surrounding air, often already by solar noon, is consistent with a recently published comparison of MODIS day-time land-surface temperatures with air temperatures. Theory further predicts a strong dependence of leaf size (which is inversely related to leaf boundary-layer conductance, and therefore to absolute magnitude of ΔT) on moisture availability. Theoretically, leaf size should be determined by either night-time constraints (risk of frost damage to active leaves) or day-time constraints (risk of heat stress damage),with the former likely to predominate - thereby restricting the occurrence of large leaves - at high latitudes. In low latitudes, daytime maximum leaf size is predicted to increase with temperature, provided that water is plentiful. If water is restricted, however, transpiration cannot proceed at the Priestley-Taylor rate, and it quickly becomes advantageous for plants to have small leaves, which do not heat up much above the temperature of their surroundings. The difference between leaf

  18. Dynamic Model of High Temperature PEM Fuel Cell Stack Temperature

    DEFF Research Database (Denmark)

    Andreasen, Søren Juhl; Kær, Søren Knudsen

    2007-01-01

    cathode air cooled 30 cell HTPEM fuel cell stack developed at the Institute of Energy Technology at Aalborg University. This fuel cell stack uses PEMEAS Celtec P-1000 membranes, runs on pure hydrogen in a dead end anode configuration with a purge valve. The cooling of the stack is managed by running......The present work involves the development of a model for predicting the dynamic temperature of a high temperature PEM (HTPEM) fuel cell stack. The model is developed to test different thermal control strategies before implementing them in the actual system. The test system consists of a prototype...... the stack at a high stoichiometric air flow. This is possible because of the PBI fuel cell membranes used, and the very low pressure drop in the stack. The model consists of a discrete thermal model dividing the stack into three parts: inlet, middle and end and predicting the temperatures in these three...

  19. High temperature corrosion of metals

    International Nuclear Information System (INIS)

    Quadakkers, W.J.; Schuster, H.; Ennis, P.J.

    1988-08-01

    This paper covers three main topics: 1. high temperature oxidation of metals and alloys, 2. corrosion in sulfur containing environments and 3. structural changes caused by corrosion. The following 21 subjects are discussed: Influence of implanted yttrium and lanthanum on the oxidation behaviour of beta-NiA1; influence of reactive elements on the adherence and protective properties of alumina scales; problems related to the application of very fine markers in studying the mechanism of thin scale formation; oxidation behaviour of chromia forming Co-Cr-Al alloys with or without reactive element additions; growth and properties of chromia-scales on high-temperature alloys; quantification of the depletion zone in high temperature alloys after oxidation in process gas; effects of HC1 and of N2 in the oxidation of Fe-20Cr; investigation under nuclear safety aspects of Zircaloy-4 oxidation kinetics at high temperatures in air; on the sulfide corrosion of metallic materials; high temperature sulfide corrosion of Mn, Nb and Nb-Si alloys; corrosion behaviour or NiCrAl-based alloys in air and air-SO2 gas mixtures; sulfidation of cobalt at high temperatures; preoxidation for sulfidation protection; fireside corrosion and application of additives in electric utility boilers; transport properties of scales with complex defect structures; observations of whiskers and pyramids during high temperature corrosion of iron in SO2; corrosion and creep of alloy 800H under simulated coal gasification conditions; microstructural changes of HK 40 cast alloy caused by exploitation in tubes in steam reformer installation; microstructural changes during exposure in corrosive environments and their effect on mechanical properties; coatings against carburization; mathematical modeling of carbon diffusion and carbide precipitation in Ni-Cr-based alloys. (MM)

  20. Possibilities for using a temperature-controlled pyrolysis method in order to determine the bonding form of mecury in soils and sediments; Moeglichkeiten der Anwendung eines temperaturgesteuerten Pyrolyseverfahrens zur Bestimmung der Bindungsform des Quecksilbers in Boeden und Sedimenten

    Energy Technology Data Exchange (ETDEWEB)

    Biester, H.

    1994-12-31

    The bonding behaviour of mercury in solids was investigated by means of a temperature-controlled pyrolysis method. Starting from the special property of elemental mercury to evaporate already at room temperature, a method was developed which permits to characterize different mercury bonding forms on the basis of Hg evaporation behaviour from solids at continuously increased temperature. The method starts from the assumption that it is possible to thermally reduce compounded mercury and release it in elemental form. The focus of the work was on the study of Hg bonding behaviour in soils and sediments. The soil samples used were from the areas of two mercury deposits, different kyanizing sites, some former mirror factories, and a chlor-alkali electrolysis workshop. The investigated sediments are a collection of mercury-polluted samples from the rivers Elbe, Rhine, Murg, the Rio Sao Joao de Meriti (Brazil) and some brooks and rivers of the Saar-Nahe depression. (orig./EF) [Deutsch] In der vorliegenden Arbeit wurde das Bindungsverhalten von Quecksilber in Feststoffen mittels eines temperaturgesteuerten Pyrolyseverfahrens untersucht. Ausgehend von der besonderen Eigenschaften des elementaren Quecksilbers, bereits bei Zimmertemperatur zu verdampfen, wurde ein Verfahren entwickelt, das eine Charakterisierung verschiedener Quecksilberbindungsformen aufgrund des Abdampfverhaltens des Hg aus dem Feststoff unter kontinuierlicher Temperaturerhoehung zulaesst. Dem Verfahren liegt dabei die Annahme zugrunde, dass sich das Quecksilber in seinen Verbindungen thermisch reduzieren und in elementarer Form freisetzen laesst. Durch den kontinuierlichen Aufheizprozess erfolgt die Freisetzung des Quecksilbers in Abhaengigkeit von der Bindungsstaerke in unterschiedlichen Temperaturbereichen. Die Darstellung der Ergebnisse erfolgte in Form von Abdampfkurven, die die Extinktion in Abhaengigkeit von der Temperatur darstellen. Der Schwerpunkt dieser Arbeit lag auf der Untersuchung des

  1. High temperature microscope (1961); Microscopie a haute temperature (1961)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-06-15

    The purpose of this work is the realization of an apparatus for observation of radioactive metallic samples at high temperature and low pressure. The operating conditions are as follows: to limit oxidation of the metal, pressure of about 10{sup -6} mm of Hg is maintained in the furnace. In case the oxidation of the sample would be too important, on ultra vacuum. device could be used; working temperatures range between room temperature and 1200 deg. C; furnace temperature is regulated; observation is done ever in polarized light or interference contrast; to insure protection of the operator, the apparatus is placed in a glove-box. With that apparatus, we have observed the {alpha}{yields}{beta}, {beta}{yields}{gamma} transformations of uranium. A movie has been done. (author) [French] Le but de ce travail est la realisation d'une appareillage permettant l'observation a chaud et sous vide d'echantillons metalliques radioactifs. Cet appareillage fonctionne dans les conditions suivantes: l'echantillon est chauffe sous une pression de l'ordre de 10{sup -6} mm de mercure afin de limiter l'oxydation du materiau examine. L'utilisation eventuelle d'un groupe de pompage pour ultra vide est prevue; l'echantillon peut etre porte a une temperature comprise entre quelques degres et 1200 deg. C; la temperature du four est regulee; l'observation s'effectue soit en lumiere polarisee soit en contraste interferentiel; l'appareil est dipose dans une boite a gants afin d'assurer la protection de l'operateur contre les poussieres radioactives; Les transformations {alpha}{yields}{beta}, {beta}{yields}{gamma} de l'uranium ont ete observees. Un film a ete realise. (auteur)

  2. VAB Temperature and Humidity Study

    Science.gov (United States)

    Lane, John E.; Youngquist, Robert C.; Muktarian, Edward; Nurge, Mark A.

    2014-01-01

    In 2012, 17 data loggers were placed in the VAB to measure temperature and humidity at 10-minute intervals over a one-year period. In 2013, the data loggers were replaced with an upgraded model and slight adjustments to their locations were made to reduce direct solar heating effects. The data acquired by the data loggers was compared to temperature data provided by three wind towers located around the building. It was found that the VAB acts as a large thermal filter, delaying and reducing the thermal oscillations occurring outside of the building. This filtering is typically more pronounced at higher locations in the building, probably because these locations have less thermal connection with the outside. We surmise that the lower elevations respond more to outside temperature variations because of air flow through the doors. Temperatures inside the VAB rarely exceed outdoor temperatures, only doing so when measurements are made directly on a surface with connection to the outside (such as a door or wall) or when solar radiation falls directly on the sensor. A thermal model is presented to yield approximate filter response times for various locations in the building. Appendix A contains historical thermal and humidity data from 1994 to 2009.

  3. High Temperature Transparent Furnace Development

    Science.gov (United States)

    Bates, Stephen C.

    1997-01-01

    This report describes the use of novel techniques for heat containment that could be used to build a high temperature transparent furnace. The primary objective of the work was to experimentally demonstrate transparent furnace operation at 1200 C. Secondary objectives were to understand furnace operation and furnace component specification to enable the design and construction of a low power prototype furnace for delivery to NASA in a follow-up project. The basic approach of the research was to couple high temperature component design with simple concept demonstration experiments that modify a commercially available transparent furnace rated at lower temperature. A detailed energy balance of the operating transparent furnace was performed, calculating heat losses through the furnace components as a result of conduction, radiation, and convection. The transparent furnace shells and furnace components were redesigned to permit furnace operation at at least 1200 C. Techniques were developed that are expected to lead to significantly improved heat containment compared with current transparent furnaces. The design of a thermal profile in a multizone high temperature transparent furnace design was also addressed. Experiments were performed to verify the energy balance analysis, to demonstrate some of the major furnace improvement techniques developed, and to demonstrate the overall feasibility of a high temperature transparent furnace. The important objective of the research was achieved: to demonstrate the feasibility of operating a transparent furnace at 1200 C.

  4. Extreme Maximum Land Surface Temperatures.

    Science.gov (United States)

    Garratt, J. R.

    1992-09-01

    There are numerous reports in the literature of observations of land surface temperatures. Some of these, almost all made in situ, reveal maximum values in the 50°-70°C range, with a few, made in desert regions, near 80°C. Consideration of a simplified form of the surface energy balance equation, utilizing likely upper values of absorbed shortwave flux (1000 W m2) and screen air temperature (55°C), that surface temperatures in the vicinity of 90°-100°C may occur for dry, darkish soils of low thermal conductivity (0.1-0.2 W m1 K1). Numerical simulations confirm this and suggest that temperature gradients in the first few centimeters of soil may reach 0.5°-1°C mm1 under these extreme conditions. The study bears upon the intrinsic interest of identifying extreme maximum temperatures and yields interesting information regarding the comfort zone of animals (including man).

  5. Human influence on Canadian temperatures

    Science.gov (United States)

    Wan, Hui; Zhang, Xuebin; Zwiers, Francis

    2018-02-01

    Canada has experienced some of the most rapid warming on Earth over the past few decades with a warming rate about twice that of the global mean temperature since 1948. Long-term warming is observed in Canada's annual, winter and summer mean temperatures, and in the annual coldest and hottest daytime and nighttime temperatures. The causes of these changes are assessed by comparing observed changes with climate model simulated responses to anthropogenic and natural (solar and volcanic) external forcings. Most of the observed warming of 1.7 °C increase in annual mean temperature during 1948-2012 [90% confidence interval (1.1°, 2.2 °C)] can only be explained by external forcing on the climate system, with anthropogenic influence being the dominant factor. It is estimated that anthropogenic forcing has contributed 1.0 °C (0.6°, 1.5 °C) and natural external forcing has contributed 0.2 °C (0.1°, 0.3 °C) to the observed warming. Up to 0.5 °C of the observed warming trend may be associated with low frequency variability of the climate such as that represented by the Pacific decadal oscillation (PDO) and North Atlantic oscillation (NAO). Overall, the influence of both anthropogenic and natural external forcing is clearly evident in Canada-wide mean and extreme temperatures, and can also be detected regionally over much of the country.

  6. Magnons at the Curie temperature

    International Nuclear Information System (INIS)

    Poling, D.A.

    1982-01-01

    Random phase approximations (RPA) have very successfully treated spin wave excitations in Heisenberg ferromagnets at low temperatures. The role played by these magnons at the order-disorder transition, however, has been a topic which has eluded RPA theories to date. In light of recent data 1 , the idea of magnons at the Curie temperature and above has become more difficult to refute. This adds incentive to attempt to model interacting magnons at the Curie temperature. This work examines some attempts to formulate higher random phase approximations and discusses why they fail as they approach the transition temperature. A new interpretation of some work by Parmenter and author 2 is presented. The nature of the approximations made in that work is discussed, and an attempt is made to eliminate incorrect contributions from the energetically disfavored paramagnetic state to the correct magnon renormalization. A solution is presented which has the proper low temperature behavior as demonstrated by Dyson 3 restored and the reentrant behavior eliminated. An examination of how close this model comes to behaving correctly is performed, and a comparison is made to some recent work by Parmenter 4

  7. Betavoltaic performance under extreme temperatures

    Directory of Open Access Journals (Sweden)

    Adams Tom

    2016-01-01

    Full Text Available Longevity of sensors and portable devices is severely limited by temperature, chemical instability, and electrolyte leakage issues associated with conventional electrochemical batteries. Betavoltaics, which operate similar to photo voltaics, can operate in a wide temperature range safely without permanent degradation. Though not a new concept, which began in the 1950's and peaked in the mid 1970's, research has been minimal and sporadic until recent advancements in ultra-low power electronics and materialization of low power applications. The technology is rapidly maturing, generating research, and development in increasing the beta emitting source and semiconductor efficiencies. This study presents an update on betavoltaic technology, results from temperature evaluation on commercially available General Licensed betavoltaic cells, development of a hybrid system for latent and burst power, modeling and simulation techniques and results, and current and proposed research and development. Betavoltaic performance was successfully demonstrated for a wide temperature range (-30°C to 70°C. Short circuit current and open circuit voltage were used to compare electrical performance. Results indicate that the open-circuit voltage and maximum power decreased as temperature increased due to increases in the semiconductor's intrinsic carrier concentration.

  8. Temperature Distribution in a Displacement Ventilated Room

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    The vertical temperature gradient is normally given as a linear temperature distribution between a minimum temperature close to the floor and a maximum temperature close to the ceiling. The minimum temperature can either be a constant fraction of a load dependent difference or it can be connected...

  9. Numerical simulation of the unsteady heat-transfer in a turbine-rotor in consideration of hot-spot effects. Final report; AG-Turbo-Vorhaben 1.324: Numerische Simulation des instationaeren Waermeuebergangs an einem Turbinenrotor unter Einschluss von Heissstellen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Nuernberger, D.

    2001-07-01

    In this research project the influence of hot-gas effects, so called hot-spots, to the thermal load of high pressure turbine rotors was investigated in. Generally the total process efficiency can massively be improved by an increase of the temperature level at turbine entrance. However the temperatures of modern gas turbines can only be realized by efficient cooling techniques of the turbine blade materials. Furthermore the turbine stages close to the combustion chamber are exposed to an additional thermal loading due to the so called hot-spots. These streaks of unburned fuel entering the first turbine passages can cause a dramatic increase of local temperature in their afterburning process. For an optimized thermal design a detailed knowledge of these hot-streaks and their interaction with the unsteady flow through the turbomachinery flow is necessary. With this research program time accurate numerical investigations were performed to analyze the interaction process between the occurring hot gases and the high loaded turbine rotors. The numerical simulations started with fundamental investigation of the hot-spot and heat transfer modeling. Based on these developements threedimensional time accurate simulations for a realistic high pressure turbine configuration were performed. Herein the unsteady mechanisms of the hot gases and their influence on the heat transfer of the blade material was analyzed. In total the hot-streaks lead to a massiv increase of the thermal loading mainly on the pressure sides. (orig.) [German] Im Rahmen dieses Forschungsvorhabens wurden der Einfluss von Heissgaseffekten, sogenannten Hot-Spots auf die thermische Belastung von Turbinenrotoren numerisch untersucht. Gemeinhin sind die sehr hohen Turbineneintrittstemperaturen, deren Erhoehung einen wesentlichen Beitrag zur Verbesserung des gesamten Prozesswirkungsgrades leisten, nur durch effektive Kuehlungsmassnahmen der Schaufelwerkstoffe realisierbar. Zudem erfahren diese unmittelbar dem

  10. Seasonal temperature extremes in Potsdam

    Science.gov (United States)

    Kundzewicz, Zbigniew; Huang, Shaochun

    2010-12-01

    The awareness of global warming is well established and results from the observations made on thousands of stations. This paper complements the large-scale results by examining a long time-series of high-quality temperature data from the Secular Meteorological Station in Potsdam, where observation records over the last 117 years, i.e., from January 1893 are available. Tendencies of change in seasonal temperature-related climate extremes are demonstrated. "Cold" extremes have become less frequent and less severe than in the past, while "warm" extremes have become more frequent and more severe. Moreover, the interval of the occurrence of frost has been decreasing, while the interval of the occurrence of hot days has been increasing. However, many changes are not statistically significant, since the variability of temperature indices at the Potsdam station has been very strong.

  11. Flexible Temperature Sensors on Fibers

    Directory of Open Access Journals (Sweden)

    Marcin Sloma

    2010-08-01

    Full Text Available The aim of this paper is to present research dedicated to the elaboration of novel, miniaturized flexible temperature sensors for textronic applications. Examined sensors were manufactured on a single yarn, which ensures their high flexibility and good compatibility with textiles. Stable and linear characteristics were obtained by special technological process and applied temperature profiles. As a thermo-sensitive materials the innovative polymer compositions filled with multiwalled carbon nanotubes were used. Elaborated material was adapted to printing and dip-coating techniques to produce NTC composites. Nanotube sensors were free from tensometric effect typical for other carbon-polymer sensor, and demonstrated TCR of 0.13%/K. Obtained temperature sensors, compatible with textile structure, can be applied in rapidly developing smart textiles and be used for health and protections purposes.

  12. Brain temperature and exercise performance

    DEFF Research Database (Denmark)

    Nybo, Lars

    2012-01-01

    Events arising within the central nervous system seem to play a major factor in the aetiology of hyperthermia-induced fatigue. Thus, various studies with superimposed electrical nerve stimulation or transcranial magnetic stimulation have shown that both passive and exercise-induced hyperthermia...... temperature in exercising goats indicate that excessive brain hyperthermia will directly affect motor performance. However, several homeostatic changes arise in parallel with hyperthermia including factors that may influence both peripheral and central fatigue and it is likely that these changes interact...... will impair voluntary motor activation during sustained maximal contractions. In humans the brain temperature increases in parallel with that of the body core making it very difficult to evaluate the independent effect of the cerebral temperature. Experiments with separate manipulation of the brain...

  13. Vessels for elevated temperature service

    International Nuclear Information System (INIS)

    O'Donnell, W.J.; Porowski, J.S.

    1983-01-01

    The subject is covered in chapters, entitled: introduction (background; elevated temperature concerns; design tools); design of pressure vessels for elevated temperature per ASME code; basic elevated temperature failure modes; allowable stresses and strains per ASME code (basic allowable stress limits; ASME code limits for bending; time-fraction summations; strain limits; buckling and instability; negligible creep and stress-rupture effects); combined membrane and bending stresses in creep regime; thermal stress cycles; bounding methods based on elastic core concept (bounds on accumulated strains; more accurate bounds; strain ranges; maximum stresses; strains at discontinuities); elastic follow-up; creep strain concentrations; time-dependent fatigue (combined creep rupture and fatigue damage; limits for inelastic design analyses; limits for elastic design analyses); flaw evaluation techniques; type 316 stainless steel; type 304 stainless steel; steel 2 1/4Cr1Mo; Inconel 718; Incolloy 800; Hastelloy X; detailed inelastic design analyses. (U.K.)

  14. Taking the moon's internal temperature

    International Nuclear Information System (INIS)

    Duba, A.G.

    1976-01-01

    LLL geophysicists were instrumental in resolving a serious discrepancy between lunar magnetic-field data and melting studies of lunar basalts brought back from the Moon by Apollo astronauts. Estimates of the subsurface temperatures, based on lunar electrical conductivity measurements and laboratory experiments, were hundreds of degrees below those given by models using known melting points of various minerals. The work uncovered a basic flaw in previous measurements. New measurements under more realistic conditions brought the electrical-conductivity temperature estimates into agreement with temperatures derived from melting experiments. This same work also contributed to in situ coal gasification studies; to ERDA's dry, hot-rock geothermal effort; and to a program of monitoring for seismic evidence of clandestine nuclear testing. 4 figures

  15. Michelson interferometer for measuring temperature

    Science.gov (United States)

    Xie, Dong; Xu, Chunling; Wang, An Min

    2017-09-01

    We investigate that temperature can be measured by a modified Michelson interferometer, where at least one reflected mirror is replaced by a thermalized sample. Both of two mirrors replaced by the corresponding two thermalized samples can help to approximatively improve the resolution of temperature up to twice than only one mirror replaced by a thermalized sample. For further improving the precision, a nonlinear medium can be employed. The Michelson interferometer is embedded in a gas displaying Kerr nonlinearity. We obtain the analytical equations and numerically calculate the precision with parameters within the reach of current technology, proving that the precision of temperature can be greatly enhanced by using a nonlinear medium. Our results show that one can create an accurate thermometer by measuring the photons in the Michelson interferometer, with no need to directly measure the population of thermalized sample.

  16. Automatic low-temperature calorimeter

    International Nuclear Information System (INIS)

    Malyshev, V.M.; Mil'ner, G.A.; Shibakin, V.F.; Sorkin, E.L.

    1986-01-01

    This paper describes a low-temperature adiabatic calorimeter with a range of 1.5-500K. The system for maintaining adiabatic conditions is implemented by two resitance thermometers, whose sensitivity at low temperatures is several orders higher than that of thermocouples. The calorimeter cryostat is installed in an STG-40 portable Dewar flask. The calorimeter is controlled by an Elektronika-60 microcomputer. Standard platinum and germanium thermometers were placed inside of the calorimeter to calibrate the thermometers of the calorimeter and the shield, and the specific heats of specimens of OSCh 11-4 copper and KTP-8 paste were measured to demonstrate the possibilities of the described calorimeter. Experience with the calorimeter has shown that a thorough study of the dependence of heat capacity on temperature (over 100 points for one specimen) can be performed in one or two dats

  17. The upper atmosphere of Uranus - Mean temperature and temperature variations

    Science.gov (United States)

    Dunham, E.; Elliot, J. L.; Gierasch, P. J.

    1980-01-01

    The number-density, pressure, and temperature profiles of the Uranian atmosphere in the pressure interval from 0.3 to 30 dynes/sq cm are derived from observations of the occultation of SAO 158687 by Uranus on 1977 March 10, observations made from the Kuiper Airborne Observatory and the Cape Town station of the South African Astronomical Observatory. The mean temperature is found to be about 95 K, but peak-to-peak variations from 10 K to 20 K or more exist on a scale of 150 km or 3 scale heights. The existence of a thermal inversion is established, but the inversion is much weaker than the analogous inversion on Neptune. The mean temperature can be explained by solar heating in the 3.3 micron methane band with a methane mixing ratio of 4 x 10 to the -6th combined with the cooling effect of ethane with a mixing ratio of not greater than 4 x 10 to the -6th. The temperature variations are probably due to a photochemical process that has formed a Chapman layer.

  18. Zero temperature dissipation and holography

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Pinaki; Sathiapalan, B. [Institute of Mathematical Sciences,CIT Campus, Taramani, Chennai 600 113 (India)

    2016-04-14

    We use holographic techniques to study the zero-temperature limit of dissipation for a Brownian particle moving in a strongly coupled CFT at finite temperature in various space-time dimensions. The dissipative term in the boundary theory for ω→0, T→0 with ω/T held small and fixed, does not match the same at T=0, ω→0. Thus the T→0 limit is not smooth for ω

  19. "Green" High-Temperature Polymers

    Science.gov (United States)

    Meador, Michael A.

    1998-01-01

    PMR-15 is a processable, high-temperature polymer developed at the NASA Lewis Research Center in the 1970's principally for aeropropulsion applications. Use of fiber-reinforced polymer matrix composites in these applications can lead to substantial weight savings, thereby leading to improved fuel economy, increased passenger and payload capacity, and better maneuverability. PMR-15 is used fairly extensively in military and commercial aircraft engines components seeing service temperatures as high as 500 F (260 C), such as the outer bypass duct for the F-404 engine. The current world-wide market for PMR-15 materials (resins, adhesives, and composites) is on the order of $6 to 10 million annually.

  20. Finite temperature approach to confinement

    International Nuclear Information System (INIS)

    Gave, E.; Jengo, R.; Omero, C.

    1980-06-01

    The finite temperature treatment of gauge theories, formulated in terms of a gauge invariant variable as in a Polyakov method, is used as a device for obtaining an effective theory where the confinement test takes the form of a correlation function. The formalism is discussed for the abelian CPsup(n-1) model in various dimensionalities and for the pure Yang-Mills theory in the limit of zero temperature. In the latter case a class of vortex like configurations of the effective theory which induce confinement correspond in particular to the instanton solutions. (author)

  1. High-temperature metallography setup

    International Nuclear Information System (INIS)

    Blumenfeld, M.; Shmarjahu, D.; Elfassy, S.

    1979-06-01

    A high-temperature metallography setup is presented. In this setup the observation of processes such as that of copper recrystallization was made possible, and the structure of metals such as uranium could be revealed. A brief historical review of part of the research works that have been done with the help of high temperature metallographical observation technique since the beginning of this century is included. Detailed description of metallographical specimen preparation technique and theoretical criteria based on the rate of evaporation of materials present on the polished surface of the specimens are given

  2. High temperature corrosion in gasifiers

    Directory of Open Access Journals (Sweden)

    Bakker Wate

    2004-01-01

    Full Text Available Several commercial scale coal gasification combined cycle power plants have been built and successfully operated during the last 5-10 years. Supporting research on materials of construction has been carried out for the last 20 years by EPRI and others. Emphasis was on metallic alloys for heat exchangers and other components in contact with hot corrosive gases at high temperatures. In this paper major high temperature corrosion mechanisms, materials performance in presently operating gasifiers and future research needs will be discussed.

  3. Selfconsistent calculations at finite temperatures

    International Nuclear Information System (INIS)

    Brack, M.; Quentin, P.

    1975-01-01

    Calculations have been done for the spherical nuclei 40 Ca, 208 Pb and the hypothetical superheavy nucleus with Z=114, A=298, as well as for the deformed nucleus 168 Yb. The temperature T was varied from zero up to 5 MeV. For T>3 MeV, some numerical problems arise in connection with the optimization of the basis when calculating deformed nuclei. However, at these high temperatures the occupation numbers in the continuum are sufficiently large so that the nucleus starts evaporating particles and no equilibrium state can be described. Results are obtained for excitation energies and entropies. (Auth.)

  4. Low-temperature thermal expansion

    International Nuclear Information System (INIS)

    Collings, E.W.

    1986-01-01

    This chapter discusses the thermal expansion of insulators and metals. Harmonicity and anharmonicity in thermal expansion are examined. The electronic, magnetic, an other contributions to low temperature thermal expansion are analyzed. The thermodynamics of the Debye isotropic continuum, the lattice-dynamical approach, and the thermal expansion of metals are discussed. Relative linear expansion at low temperatures is reviewed and further calculations of the electronic thermal expansion coefficient are given. Thermal expansions are given for Cu, Al and Ti. Phenomenologic thermodynamic relationships are also discussed

  5. Superhigh Temperatures and Acoustic Cavitation

    CERN Document Server

    Belyaev, V B; Miller, M B; Sermyagin, A V; Topolnikov, A S

    2003-01-01

    The experimental results on thermonuclear synthesis under acoustic cavitation have been analyzed with the account of the latest data and their discussion. The analysis testifies that this avenue of research is a very promising one. The numerical calculations of the D(d, n)^{3}He reaction rate in the deuterated acetone (C_{3}D_{6}O) under the influence of ultrasound depending on T environment temperature within the range T=249-295 K have been carried out within the framework of hydrodynamic model. The results show that it is possible to improve substantially the effect/background relationship in experiments by decreasing the fluid temperature twenty-thirty degrees below zero.

  6. Covariant gauges at finite temperature

    CERN Document Server

    Landshoff, Peter V

    1992-01-01

    A prescription is presented for real-time finite-temperature perturbation theory in covariant gauges, in which only the two physical degrees of freedom of the gauge-field propagator acquire thermal parts. The propagators for the unphysical degrees of freedom of the gauge field, and for the Faddeev-Popov ghost field, are independent of temperature. This prescription is applied to the calculation of the one-loop gluon self-energy and the two-loop interaction pressure, and is found to be simpler to use than the conventional one.

  7. High temperature water chemistry monitoring

    International Nuclear Information System (INIS)

    Aaltonen, P.

    1992-01-01

    Almost all corrosion phenomena in nuclear power plants can be prevented or at least damped by water chemistry control or by the change of water chemistry control or by the change of water chemistry. Successful water chemistry control needs regular and continuous monitoring of such water chemistry parameters like dissolved oxygen content, pH, conductivity and impurity contents. Conventionally the monitoring is carried out at low pressures and temperatures, which method, however, has some shortcomings. Recently electrodes have been developed which enables the direct monitoring at operating pressures and temperatures. (author). 2 refs, 5 figs

  8. Energy Doubler cryoloop temperature monitor system

    International Nuclear Information System (INIS)

    Pucci, G.; Howard, D.

    1981-10-01

    The Cryoloop Temperature Monitor System is a fully electronic system designed to monitor temperature at key points in the Energy Doubler cryoloop system. It is used for cryoloop diagnostics, temperature studies, and cooldown valve control

  9. Asymetric change of daily temperature range: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Kukla, G. [ed.] [Columbia Univ., Palisades, NY (United States). Lamont-Doherty Earth Observatory; Karl, T.R. [ed.] [National Climatic Data Center, Asheville, NC (United States); Riches, M.R. [ed.] [USDOE, Washington, DC (United States)

    1994-04-01

    This report is a compilation of abstracts of papers presented at the MINIMAX workshop. Topics include; temperature fluxes, influence of clouds on temperature, anthropogenic influences on temperature flux, and carbon dioxide and aerosol induced greenhouse effect.

  10. Asymetric change of daily temperature range: Proceedings

    International Nuclear Information System (INIS)

    Kukla, G.; Riches, M.R.

    1994-04-01

    This report is a compilation of abstracts of papers presented at the MINIMAX workshop. Topics include; temperature fluxes, influence of clouds on temperature, anthropogenic influences on temperature flux, and carbon dioxide and aerosol induced greenhouse effect

  11. Vol. 5: Low Temperature Physics

    International Nuclear Information System (INIS)

    Sitenko, A.

    1993-01-01

    Problems of modern physics and the situation with physical research in Ukraine are considered. Programme of the conference includes scientific and general problems. Its proceeding are published in 6 volumes. The papers presented in this volume refer to low-temperature physics

  12. Ultrahigh Temperature Capacitive Pressure Sensor

    Science.gov (United States)

    Harsh, Kevin

    2014-01-01

    Robust, miniaturized sensing systems are needed to improve performance, increase efficiency, and track system health status and failure modes of advanced propulsion systems. Because microsensors must operate in extremely harsh environments, there are many technical challenges involved in developing reliable systems. In addition to high temperatures and pressures, sensing systems are exposed to oxidation, corrosion, thermal shock, fatigue, fouling, and abrasive wear. In these harsh conditions, sensors must be able to withstand high flow rates, vibration, jet fuel, and exhaust. In order for existing and future aeropropulsion turbine engines to improve safety and reduce cost and emissions while controlling engine instabilities, more accurate and complete sensor information is necessary. High-temperature (300 to 1,350 C) capacitive pressure sensors are of particular interest due to their high measurement bandwidth and inherent suitability for wireless readout schemes. The objective of this project is to develop a capacitive pressure sensor based on silicon carbon nitride (SiCN), a new class of high-temperature ceramic materials, which possesses excellent mechanical and electric properties at temperatures up to 1,600 C.

  13. Proximity effect at Millikelvin temperatures

    International Nuclear Information System (INIS)

    Mota, A.C.

    1986-01-01

    Proximity effects have been studied extensively for the past 25 years. Typically, they are in films several thousand angstroms thick at temperatures not so far below T/sub CNS/, the transition temperature of the NS system. Interesting is, however, the proximity effect at temperatures much lower than T/sub CNS/. In this case, the Cooper-pair amplitudes are not small and very long pair penetration lengths into the normal metal can be expected. Thus, we have observed pair penetration lengths. For these investigations very suitable specimens are commercial wires of one filament of NbTi or Nb embedded in a copper matrix. The reasons are the high transmission coefficient at the interface between the copper and the superconductor and the fact that the copper in these commercial wires is rather clean with electron free paths between 5 to 10 μm long. In this paper, the magnetic properties of thick proximity systems in the range of temperatures between T/sub CNS/ and 5 x 10/sup -4/ T/sub CNS/ in both low and high magnetic fields are discussed

  14. Room temperature cryogenic test interface

    International Nuclear Information System (INIS)

    Faris, S. M.; Davidson, A.; Moskowitz, P. A.; Sai-Halasz, G. A.

    1985-01-01

    This interface permits the testing of high speed semiconductor devices (room-temperature chips) by a Josephson junction sampling device (cryogenic chip) without intolerable loss of resolution. The interface comprises a quartz pass-through plug which includes a planar transmission line interconnecting a first chip station, where the cryogenic chip is mounted, and a second chip station, where the semiconductor chip to be tested is temporarily mounted. The pass-through plug has a cemented long half-cylindrical portion and short half-cylindrical portion. The long portion carries the planar transmission line, the ends of which form the first and second chip mounting stations. The short portion completes the cylinder with the long portion for part of its length, where a seal can be achieved, but does not extend over the chip mounting stations. Sealing is by epoxy cement. The pass-through plug is sealed in place in a flange mounted to the chamber wall. The first chip station, with the cryogenic chip attached, extends into the liquid helium reservoir. The second chip station is in the room temperature environment required for semiconductor operation. Proper semiconductor operating temperature is achieved by a heater wire and control thermocouple in the vicinity of each other and the second chip mounting station. Thermal isolation is maintained by vacuum and seals. Connections for power and control, for test result signals, for temperature control and heating, and for vacuum complete the test apparatus

  15. Material Properties at Low Temperature

    International Nuclear Information System (INIS)

    Duthil, P

    2014-01-01

    From ambient down to cryogenic temperatures, the behaviour of materials changes greatly. Mechanisms leading to variations in electrical, thermal, mechanical, and magnetic properties in pure metals, alloys, and insulators are briefly introduced from a general engineering standpoint. Data sets are provided for materials commonly used in cryogenic systems for design purposes

  16. High-temperature plasma physics

    International Nuclear Information System (INIS)

    Furth, H.P.

    1988-03-01

    Both magnetic and inertial confinement research are entering the plasma parameter range of fusion reactor interest. This paper reviews the individual and common technical problems of these two approaches to the generation of thermonuclear plasmas, and describes some related applications of high-temperature plasma physics

  17. High-Temperature Vibration Damper

    Science.gov (United States)

    Clarke, Alan; Litwin, Joel; Krauss, Harold

    1987-01-01

    Device for damping vibrations functions at temperatures up to 400 degrees F. Dampens vibrational torque loads as high as 1,000 lb-in. but compact enough to be part of helicopter rotor hub. Rotary damper absorbs energy from vibrating rod, dissipating it in turbulent motion of viscous hydraulic fluid forced by moving vanes through small orifices.

  18. Safe Minimum Internal Temperature Chart

    Science.gov (United States)

    ... Internal Temperature Chart Safe steps in food handling, cooking, and storage are essential in preventing foodborne illness. You can't see, smell, or taste harmful bacteria that may cause illness. In every step of food preparation, follow the four guidelines to keep food safe: ...

  19. High temperature soldering of graphite

    International Nuclear Information System (INIS)

    Anikin, L.T.; Kravetskij, G.A.; Dergunova, V.S.

    1977-01-01

    The effect is studied of the brazing temperature on the strength of the brazed joint of graphite materials. In one case, iron and nickel are used as solder, and in another, molybdenum. The contact heating of the iron and nickel with the graphite has been studied in the temperature range of 1400-2400 ged C, and molybdenum, 2200-2600 deg C. The quality of the joints has been judged by the tensile strength at temperatures of 2500-2800 deg C and by the microstructure. An investigation into the kinetics of carbon dissolution in molten iron has shown that the failure of the graphite in contact with the iron melt is due to the incorporation of iron atoms in the interbase planes. The strength of a joint formed with the participation of the vapour-gas phase is 2.5 times higher than that of a joint obtained by graphite recrystallization through the carbon-containing metal melt. The critical temperatures are determined of graphite brazing with nickel, iron, and molybdenum interlayers, which sharply increase the strength of the brazed joint as a result of the formation of a vapour-gas phase and deposition of fine-crystal carbon

  20. Room temperature ferromagnetic and photoluminescence ...

    Indian Academy of Sciences (India)

    32

    electrode, photo electronic devices, photo sensors, liquid crystal displays, electrochromic windows, solar panels and transparent coatings for solar-energy heat mirrors [11-13]. Here we report on magnetic properties of ITO nanoparticles at room temperature and at 100 K. 2. Experimental. The In1.9Sn0.1O3 powder samples ...

  1. Development of high temperature turbine

    Energy Technology Data Exchange (ETDEWEB)

    Takahara, Kitao; Nouse, Hiroyuki; Yoshida, Toyoaki; Minoda, Mitsuhiro; Matsusue, Katsutoshi; Yanagi, Ryoji

    1988-07-01

    For the contribution to the development of FJR710, high by-pass ratio turbofan engine, with the study for many years of the development of high efficiency turbine for the jet engine, the first technical prize from the Energy Resource Research Committee was awarded in April, 1988. This report introduced its technical contents. In order to improve the thermal efficiency and enlarge the output, it is very effective to raise the gas temperature at the inlet of gas turbine. For its purpose, by cooling the nozzle and moving blades and having those blades operate at lower temperature than that of the working limitation, they realized, for the first time in Japan, the technique of cooling turbine to heighten the operational gas temperature. By that technique, it was enabled to raise the gas temperature at the inlet of turbine, to 1,350/sup 0/C from 850/sup 0/C. This report explain many important points of study covering the basic test, visualizing flow experiment, material discussion and structural design in the process of development. (9 figs)

  2. Flux tubes at finite temperature

    Energy Technology Data Exchange (ETDEWEB)

    Cea, Paolo [INFN, Sezione di Bari,Via G. Amendola 173, I-70126 Bari (Italy); Dipartimento di Fisica dell’Università di Bari,Via G. Amendola 173, I-70126 Bari (Italy); Cosmai, Leonardo [INFN, Sezione di Bari,Via G. Amendola 173, I-70126 Bari (Italy); Cuteri, Francesca; Papa, Alessandro [Dipartimento di Fisica, Università della Calabria & INFN-Cosenza,Ponte Bucci, cubo 31C, I-87036 Rende (Cosenza) (Italy)

    2016-06-07

    The chromoelectric field generated by a static quark-antiquark pair, with its peculiar tube-like shape, can be nicely described, at zero temperature, within the dual superconductor scenario for the QCD confining vacuum. In this work we investigate, by lattice Monte Carlo simulations of the SU(3) pure gauge theory, the fate of chromoelectric flux tubes across the deconfinement transition. We find that, if the distance between the static sources is kept fixed at about 0.76 fm ≃1.6/√σ and the temperature is increased towards and above the deconfinement temperature T{sub c}, the amplitude of the field inside the flux tube gets smaller, while the shape of the flux tube does not vary appreciably across deconfinement. This scenario with flux-tube “evaporation” above T{sub c} has no correspondence in ordinary (type-II) superconductivity, where instead the transition to the phase with normal conductivity is characterized by a divergent fattening of flux tubes as the transition temperature is approached from below. We present also some evidence about the existence of flux-tube structures in the magnetic sector of the theory in the deconfined phase.

  3. Hawking temperature from tunnelling formalism

    OpenAIRE

    Mitra, P.

    2007-01-01

    It has recently been suggested that the attempt to understand Hawking radiation as tunnelling across black hole horizons produces a Hawking temperature double the standard value. It is explained here how one can obtain the standard value in the same tunnelling approach.

  4. Temperature distribution and thermal stress

    Indian Academy of Sciences (India)

    Abstract. Thermal effects of a double-end-pumped cubic Nd:YVO4 laser crystal are investigated in this paper. A detailed analysis of temperature distribution and thermal stress in cubic crystal with circular shape pumping is discussed. It has been shown that by considering the total input powers as constant, the ...

  5. Dual temperature isotope exchange system

    International Nuclear Information System (INIS)

    Spevack, J.S.

    1976-01-01

    Improvements in the method for isotope concentration by dual temperature exchange between feed and auxiliary fluids in a multistage system are described. In a preferred embodiment the first is a vaporizable liquid and the auxiliary fluid a gas, comprising steps for improving the heating and/or cooling and/or humidifying and/or dehumidifying operations

  6. High temperature fusion reactor design

    International Nuclear Information System (INIS)

    Harkness, S.D.; dePaz, J.F.; Gohar, M.Y.; Stevens, H.C.

    1979-01-01

    Fusion energy may have unique advantages over other systems as a source for high temperature process heat. A conceptual design of a blanket for a 7 m tokamak reactor has been developed that is capable of producing 1100 0 C process heat at a pressure of approximately 10 atmospheres. The design is based on the use of a falling bed of MgO spheres as the high temperature heat transfer system. By preheating the spheres with energy taken from the low temperature tritium breeding part of the blanket, 1086 MW of energy can be generated at 1100 0 C from a system that produces 3000 MW of total energy while sustaining a tritium breeding ratio of 1.07. The tritium breeding is accomplished using Li 2 O modules both in front of (6 cm thick) and behind (50 cm thick) the high temperature ducts. Steam is used as the first wall and front tritium breeding module coolant while helium is used in the rear tritium breeding region. The system produces 600 MW of net electricity for use on the grid

  7. Material Properties at Low Temperature

    CERN Document Server

    Duthil, P

    2014-07-17

    From ambient down to cryogenic temperatures, the behaviour of materials changes greatly. Mechanisms leading to variations in electrical, thermal, mechanical, and magnetic properties in pure metals, alloys, and insulators are briefly introduced from a general engineering standpoint. Data sets are provided for materials commonly used in cryogenic systems for design purposes.

  8. High temperature electronic gain device

    International Nuclear Information System (INIS)

    McCormick, J.B.; Depp, S.W.; Hamilton, D.J.; Kerwin, W.J.

    1979-01-01

    An integrated thermionic device suitable for use in high temperature, high radiation environments is described. Cathode and control electrodes are deposited on a first substrate facing an anode on a second substrate. The substrates are sealed to a refractory wall and evacuated to form an integrated triode vacuum tube

  9. Ion temperatures in TORTUR III

    International Nuclear Information System (INIS)

    Hendriks, F.B.

    1985-12-01

    Spatially resolved ion-energy distributions are presented for discharges in the TORTUR III tokamak. The measurements are performed in an active method, using a neutral hydrogen probing beam of 20-30 keV, to enhance charge-exchange processes along its path, as well as by the usual passive method. Ion temperatures can amount up to 1 keV

  10. Temperature and the Ideal Gas

    Science.gov (United States)

    Daisley, R. E.

    1973-01-01

    Presents some organized ideas in thermodynamics which are suitable for use with high school (GCE A level or ONC) students. Emphases are placed upon macroscopic observations and intimate connection of the modern definition of temperature with the concept of ideal gas. (CC)

  11. TEMPERATURE DEPENDENCE OF THE THERMAL ...

    African Journals Online (AJOL)

    Thermal conductivity values, in the temperature range 300 – 1200 K, have been measured in air and at atmospheric pressure for a Kenyan kaolinite refractory with 0% - 50% grog proportions. The experimental thermal conductivity values were then compared with those calculated using the Zumbrunnen et al [1] and the ...

  12. Science with low temperature detectors

    International Nuclear Information System (INIS)

    Sadoulet, B.; Lawrence Berkeley National Lab., CA; California Univ., Berkeley

    1996-01-01

    The novel technique of particle detection with low temperature detectors opens a number of new scientific opportunities. We review some of these, focusing on three generic applications: far infrared bolometry taking as an example the cosmic microwave background, X-ray spectroscopy for astrophysics and biological applications, and massive calorimeters for dark matter searches and neutrino physics. (orig.)

  13. Containment of high temperature plasmas

    International Nuclear Information System (INIS)

    Bass, R.W.; Ferguson, H.R.P.; Fletcher, H. Jr.; Gardner, J.; Harrison, B.K.; Larsen, K.M.

    1973-01-01

    Apparatus is described for confining a high temperature plasma which comprises: 1) envelope means shaped to form a toroidal hollow chamber containing a plasma, 2) magnetic field line generating means for confining the plasma in a smooth toroidal shape without cusps. (R.L.)

  14. Finite-temperature confinement transitions

    International Nuclear Information System (INIS)

    Svetitsky, B.

    1984-01-01

    The formalism of lattice gauge theory at finite temperature is introduced. The framework of universality predictions for critical behavior is outlined, and recent analytic work in this direction is reviewed. New Monte Carlo information for the SU(4) theory are represented, and possible results of the inclusion of fermions in the SU(3) theory are listed

  15. Chemistry of high temperature superconductors

    CERN Document Server

    1991-01-01

    This review volume contains the most up-to-date articles on the chemical aspects of high temperature oxide superconductors. These articles are written by some of the leading scientists in the field and includes a comprehensive list of references. This is an essential volume for researchers working in the fields of ceramics, materials science and chemistry.

  16. Material Properties at Low Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Duthil, P [Orsay, IPN (France)

    2014-07-01

    From ambient down to cryogenic temperatures, the behaviour of materials changes greatly. Mechanisms leading to variations in electrical, thermal, mechanical, and magnetic properties in pure metals, alloys, and insulators are briefly introduced from a general engineering standpoint. Data sets are provided for materials commonly used in cryogenic systems for design purposes.

  17. Properties of high temperature SQUIDS

    International Nuclear Information System (INIS)

    Falco, C.M.; Wu, C.T.

    1978-01-01

    A review is given of the present status of weak links and dc and rf biased SQUIDs made with high temperature superconductors. A method for producing reliable, reproducible devices using Nb 3 Sn is outlined, and comments are made on directions future work should take

  18. Ward identities at finite temperature

    International Nuclear Information System (INIS)

    DOlivo, J.C.; Torres, M.; Tututi, E.

    1996-01-01

    The Ward identities for QED at finite temperature are derived using the functional real-time formalism. They are verified by an explicit one-loop calculation. An effective causal vertex is constructed which satisfy the Ward identity with the associated retarded self-energy. copyright 1996 American Institute of Physics

  19. High temperature component life assessment

    CERN Document Server

    Webster, G A

    1994-01-01

    The aim of this book is to investigate and explain the rapid advances in the characterization of high temperature crack growth behaviour which have been made in recent years, with reference to industrial applications. Complicated mathematics has been minimized with the emphasis placed instead on finding solutions using simplified procedures without the need for complex numerical analysis.

  20. Finite-Temperature Higgs Potentials

    International Nuclear Information System (INIS)

    Dolgopolov, M.V.; Gurskaya, A.V.; Rykova, E.N.

    2016-01-01

    In the present article we consider the short description of the “Finite-Temperature Higgs Potentials” program for calculating loop integrals at vanishing external momenta and applications for extended Higgs potentials reconstructions. Here we collect the analytic forms of the relevant loop integrals for our work in reconstruction of the effective Higgs potential parameters in extended models (MSSM, NMSSM and etc.)

  1. Temperature etalon of WWER-440 reactor

    International Nuclear Information System (INIS)

    Stanc, S.; Slanina, M.

    2001-01-01

    The presentation deals with the description, parameters and advantages of use of the temperature etalon. The system ensures temperature measurement of reactor outlet and inlet temperatures with high accuracy. Accuracy of temperature measurement is 0.18 deg C, accuracy of temperature difference measurement is 0.14 deg C, both with probability 0.95. Using the temperature etalon it is possible to increase accuracy of the standard temperature reactor measurements and to check their accuracy in the course of power reactor statuses in every measurement cycle. Temperature reactor etalon was installed in 12 WWER-440 units in Slovakia, Bohemia and Bulgaria. (Authors)

  2. Methods for Melting Temperature Calculation

    Science.gov (United States)

    Hong, Qi-Jun

    Melting temperature calculation has important applications in the theoretical study of phase diagrams and computational materials screenings. In this thesis, we present two new methods, i.e., the improved Widom's particle insertion method and the small-cell coexistence method, which we developed in order to capture melting temperatures both accurately and quickly. We propose a scheme that drastically improves the efficiency of Widom's particle insertion method by efficiently sampling cavities while calculating the integrals providing the chemical potentials of a physical system. This idea enables us to calculate chemical potentials of liquids directly from first-principles without the help of any reference system, which is necessary in the commonly used thermodynamic integration method. As an example, we apply our scheme, combined with the density functional formalism, to the calculation of the chemical potential of liquid copper. The calculated chemical potential is further used to locate the melting temperature. The calculated results closely agree with experiments. We propose the small-cell coexistence method based on the statistical analysis of small-size coexistence MD simulations. It eliminates the risk of a metastable superheated solid in the fast-heating method, while also significantly reducing the computer cost relative to the traditional large-scale coexistence method. Using empirical potentials, we validate the method and systematically study the finite-size effect on the calculated melting points. The method converges to the exact result in the limit of a large system size. An accuracy within 100 K in melting temperature is usually achieved when the simulation contains more than 100 atoms. DFT examples of Tantalum, high-pressure Sodium, and ionic material NaCl are shown to demonstrate the accuracy and flexibility of the method in its practical applications. The method serves as a promising approach for large-scale automated material screening in which

  3. Novel room temperature ferromagnetic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Amita [KTH Royal Inst. of Technology, Stockholm (Sweden)

    2004-06-01

    Today's information world, bits of data are processed by semiconductor chips, and stored in the magnetic disk drives. But tomorrow's information technology may see magnetism (spin) and semiconductivity (charge) combined in one 'spintronic' device that exploits both charge and 'spin' to carry data (the best of two worlds). Spintronic devices such as spin valve transistors, spin light emitting diodes, non-volatile memory, logic devices, optical isolators and ultra-fast optical switches are some of the areas of interest for introducing the ferromagnetic properties at room temperature in a semiconductor to make it multifunctional. The potential advantages of such spintronic devices will be higher speed, greater efficiency, and better stability at a reduced power consumption. This Thesis contains two main topics: In-depth understanding of magnetism in Mn doped ZnO, and our search and identification of at least six new above room temperature ferromagnetic semiconductors. Both complex doped ZnO based new materials, as well as a number of nonoxides like phosphides, and sulfides suitably doped with Mn or Cu are shown to give rise to ferromagnetism above room temperature. Some of the highlights of this work are discovery of room temperature ferromagnetism in: (1) ZnO:Mn (paper in Nature Materials, Oct issue, 2003); (2) ZnO doped with Cu (containing no magnetic elements in it); (3) GaP doped with Cu (again containing no magnetic elements in it); (4) Enhancement of Magnetization by Cu co-doping in ZnO:Mn; (5) CdS doped with Mn, and a few others not reported in this thesis. We discuss in detail the first observation of ferromagnetism above room temperature in the form of powder, bulk pellets, in 2-3 mu-m thick transparent pulsed laser deposited films of the Mn (<4 at. percent) doped ZnO. High-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) spectra recorded from 2 to 200nm areas showed homogeneous

  4. Superconducting critical temperature under pressure

    Science.gov (United States)

    González-Pedreros, G. I.; Baquero, R.

    2018-05-01

    The present record on the critical temperature of a superconductor is held by sulfur hydride (approx. 200 K) under very high pressure (approx. 56 GPa.). As a consequence, the dependence of the superconducting critical temperature on pressure became a subject of great interest and a high number of papers on of different aspects of this subject have been published in the scientific literature since. In this paper, we calculate the superconducting critical temperature as a function of pressure, Tc(P), by a simple method. Our method is based on the functional derivative of the critical temperature with the Eliashberg function, δTc(P)/δα2F(ω). We obtain the needed coulomb electron-electron repulsion parameter, μ*(P) at each pressure in a consistent way by fitting it to the corresponding Tc using the linearized Migdal-Eliashberg equation. This method requires as input the knowledge of Tc at the starting pressure only. It applies to superconductors for which the Migdal-Eliashberg equations hold. We study Al and β - Sn two weak-coupling low-Tc superconductors and Nb, the strong coupling element with the highest critical temperature. For Al, our results for Tc(P) show an excellent agreement with the calculations of Profeta et al. which are known to agree well with experiment. For β - Sn and Nb, we found a good agreement with the experimental measurements reported in several works. This method has also been applied successfully to PdH elsewhere. Our method is simple, computationally light and gives very accurate results.

  5. Static Formation Temperature Prediction Based on Bottom Hole Temperature

    Directory of Open Access Journals (Sweden)

    Changwei Liu

    2016-08-01

    Full Text Available Static formation temperature (SFT is required to determine the thermophysical properties and production parameters in geothermal and oil reservoirs. However, it is not easy to determine SFT by both experimental and physical methods. In this paper, a mathematical approach to predicting SFT, based on a new model describing the relationship between bottom hole temperature (BHT and shut-in time, has been proposed. The unknown coefficients of the model were derived from the least squares fit by the particle swarm optimization (PSO algorithm. Additionally, the ability to predict SFT using a few BHT data points (such as the first three, four, or five points of a data set was evaluated. The accuracy of the proposed method to predict SFT was confirmed by a deviation percentage less than ±4% and a high regression coefficient R2 (>0.98. The proposed method could be used as a practical tool to predict SFT in both geothermal and oil wells.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-11-01

    An ultrasonic measuring method is presented, which allows to measure the volume flow densities of the gas and the liquid phases in a pipeline. A prototype was developed in co-operation with the Technical University of Nishny Novgorod, Russia. It operates in pulse-echo and in pulse-transmission models with wave guide sensors, which can be clamped also on hot pipelines up to 350 C. The basis of the measuring method is a pattern recognition technique. In certain regions of flow rates, it determines the volume flow densities with an error of less than 10%, provided the thermodynamic parameters are almost constant. An extension of the training matrices by adding a thermodynamic parameter (temperature, pressure) allows to apply the classification method for fluids with variable physical properties, too. The pattern recognition and the ultrasonic hardware were experimentally optimised and tested. The ultrasonic signals were also classified by an unsupervised learning procedure. The found clusters show a significant similarity to flow maps known from the literature. It was shown that the method of unsupervised learning can be used for the automatic setup of flow maps. A special chapter is dedicated to the water level measurement in a segment of the main circulation line of nuclear pressurised water reactors. (orig.) [Deutsch] Es wird ein Ultraschall-Messverfahren fuer Zweiphasenstroemungen vorgestellt, das die simultane Messung der Volumenstromdichte der Gas- und Fluessigphase in einer Rohrleitung ermoeglicht. Ein Prototyp wurde in Zusammenarbeit mit der Universitaet Nishny Novgorod (Russland) aufgebaut. Es realisiert einen gepulsten Transmissions- und Reflexionsbetrieb mit Wellenleitersensoren, die auch an heisse Rohrleitungen bis zu 350 C direkt angekoppelt werden koennen. Kernstueck der Messmethode ist ein Mustererkennungsverfahren, das in bestimmten Volumenstrombereichen nach einer umfangreichen Kalibrierung (Trainingsprozess) einen Messfehler von kleiner 10% besitzt

  7. High temperature structural sandwich panels

    Science.gov (United States)

    Papakonstantinou, Christos G.

    High strength composites are being used for making lightweight structural panels that are being employed in aerospace, naval and automotive structures. Recently, there is renewed interest in use of these panels. The major problem of most commercial available sandwich panels is the fire resistance. A recently developed inorganic matrix is investigated for use in cases where fire and high temperature resistance are necessary. The focus of this dissertation is the development of a fireproof composite structural system. Sandwich panels made with polysialate matrices have an excellent potential for use in applications where exposure to high temperatures or fire is a concern. Commercial available sandwich panels will soften and lose nearly all of their compressive strength temperatures lower than 400°C. This dissertation consists of the state of the art, the experimental investigation and the analytical modeling. The state of the art covers the performance of existing high temperature composites, sandwich panels and reinforced concrete beams strengthened with Fiber Reinforced Polymers (FRP). The experimental part consists of four major components: (i) Development of a fireproof syntactic foam with maximum specific strength, (ii) Development of a lightweight syntactic foam based on polystyrene spheres, (iii) Development of the composite system for the skins. The variables are the skin thickness, modulus of elasticity of skin and high temperature resistance, and (iv) Experimental evaluation of the flexural behavior of sandwich panels. Analytical modeling consists of a model for the flexural behavior of lightweight sandwich panels, and a model for deflection calculations of reinforced concrete beams strengthened with FRP subjected to fatigue loading. The experimental and analytical results show that sandwich panels made with polysialate matrices and ceramic spheres do not lose their load bearing capability during severe fire exposure, where temperatures reach several

  8. Operating temperatures for an LMFBR

    International Nuclear Information System (INIS)

    Bhoje, S.B.; Chellapandi, P.

    1993-01-01

    The scope of the present paper is limited to structural mechanics aspects that are associated with this technology. However, for the purpose of comprehensive presentation, all the other related issues are also highlighted. For this study, a Prototype Fast Breeder Reactor (PFBR) with 500 MWe capacity is taken as the reference design. Accordingly, some critical high temperature components of PFBR are analysed in- detail for elastic, inelastic and viscoplastic behaviour towards life prediction as per the requirement of design codes (RCC-MR 87) which form basis for justifying the possibility of higher operating temperatures for LMFBRs. Since operation with higher primary sodium outlet temperature in association with higher ΔT across the core is one of the efficient techniques towards making LMFBRs cost effective, operating Temperature limits are determined for a typical pool type FBR of 500 MWe capacity. Analysis indicates that control plug in the hot pool is the most critical component which limits the operating temperature to 820 K with a ΔT across the core of 160 K. By improving the thermal hydraulic design in conjunction with the structural design optimisation at the plate-shell junctions of control plug, possibility exists to go up to 840-850 K for primary outlet sodium with a T of 160 K across the core. This will result in producing steam of about 790-800 K (520 deg. C). Apart from improving the thermal hydraulic design to mitigate the transient thermal stresses, following are also needed to demonstrate higher safety margins in the design. Reduction of thermal transients, for an example, the temperature drop in the primary sodium outlet can be reduced by decreasing the sodium flow rate to the core, during a reactor scram. Welds should be avoided at the plate-shell junctions of control plug. A complete ring with necessary fillet radius may be forged as a single piece. In case of reactor vessel, a pullout option is better for redan-stand pipe junction

  9. Domain walls at finite temperature

    International Nuclear Information System (INIS)

    Carvalho, C.A. de; Marques, G.C.; Silva, A.J. da; Ventura, I.

    1983-08-01

    It is suggested that the phase transition of lambda phi 4 theory as a function of temperature coincides with the spontaneous appearance of domain walls. Based on one-loop calculations, T sub(c) = 4M/√ lambda is estimated as the temperature for these domains to because energetically favored, to be compared with T sub(c) = 4.9M/√ lambda from effective potential calculations (which are performed directly in the broken phase). Domain walls, as well as other Types of fluctuations, disorder the system above T sub(c), leading to =0. The critical exponent for the specific heat above T sub(c) is computed; and α=2/3 + 0 (√ lambda) is obtained. (Author) [pt

  10. Diacetylene time-temperature indicators

    International Nuclear Information System (INIS)

    Patel, G.N.; Yee, K.C.

    1980-01-01

    An improved recording device is described, useful for measuring the integrated time-temperature or integrated radiation-dosage history of an article, comprising a substrate onto which an acetylenic compound, containing at least two conjugated c*c groups, in an inactive form, is deposited. The inactive form is capable of being converted by melt or solvent recrystallization to an active form, which undergoes 1,4-addition polymerization resulting in an irreversible, progressive color change. The color change produced at any given point in time represents an integrated time-temperature history of thermal annealing or integrated radiation-dosage history of exposure to actinic radiation to which an article has been exposed. Also described is a process for producing an inactive form of the acetylenic compound. A film and a fiber, made from the inactive form of an acetylenic compound are also described

  11. Heat pipes for temperature control

    International Nuclear Information System (INIS)

    Groll, M.

    1978-01-01

    Heat pipes have known for years as effective constructional elements for temperature control. With the aid of special techniques (gas, liquid, steam, and voltage control), special operating characteristics can be obtained, e.g. variable heat conduction or diode behaviour. Their main field of application is in spacecraft technology and in nuclear technology in the isothermalisation of irradiation capsules. The different control techniques are presented and critically evaluated on the basis of characteristic properties like heat transfer capacity, volume and mass requirements, complexity of structure and production, reliability, and temperature control characteristics. Advantages and shortcomings of the different concepts are derived and compared. The state of the art of these control techniques is established on the basis of four development levels. Finally, the necessity and direction of further R + D activities are discussed, and suggestions are made for further work. (orig./HP) [de

  12. 2D-FE throughflow method for multistage cooled turbines with subsonic and transonic flow. Final report; 2D-FE-Verfahren fuer die Kennfeldberechnung von vielstufigen Turbinen mit unter- und ueberkritischen Stufendruckverhaeltnissen mit variabler Kuehlluftzufuhr. Abschlussbericht zum Vorhaben 1.312

    Energy Technology Data Exchange (ETDEWEB)

    Riess, W.; Gehring, S.

    2000-07-01

    Throughflow calculations have proved to be useful tools for flow field analysis and performance prediction of multistage turbines during the design process. The advantages of this method are a very limited effort necessary for preparation and a short calculation time combined with sufficient accuracy. For the design of modern gas turbines it is necessary to consider the influence of modern cooling systems in these computations. The throughflow method presented here is based on the finite element method and includes extensions which consider radial transport processes and the influence of modern cooling systems. In order to calculate modern gas turbines with complex cooling systems the method considers arbitrary combinations of convection cooling, coolant ejection at the trailing edges, film cooling and coolant ejection at the end walls. The mixing of hot gas and coolant is calculated by simplified conservation laws. The raising mass flow due to coolant addition is considered by a modified definition of the stream function or in case of the coolant ejection at the end walls by modified boundary conditions. For a simpler application of the throughflow method the mass flow can be automatically adapted during the calculation in order to achieve a given pressure ratio. Due to the definition of the stream function in use, the mass flow can be corrected directly. Therefore the continuum equation is satisfied in the whole flow field during the calculation and the computing time is reduced. The reliability of the method is verified by calculations of a 1.5-stage turbine and the Siemens AG (KWU) high temperature gas turbine V84.3. In the 1.5-stage turbine coolant is ejected in front of the blading at different radii. The cooling system of the high temperature gas turbine consists of a combination of convective cooling and coolant ejection at the trailing edges. For both machines the calculations agree very well with the measurements. (orig.) [German

  13. Ceramics for high temperature applications

    International Nuclear Information System (INIS)

    Mocellin, A.

    1977-01-01

    Problems related to materials, their fabrication, properties, handling, improvements are examined. Silicium nitride and silicium carbide are obtained by vacuum hot-pressing, reaction sintering and chemical vapour deposition. Micrographs are shown. Mechanical properties i.e. room and high temperature strength, creep resistance fracture mechanics and fatigue resistance. Recent developments of pressureless sintered Si C and the Si-Al-O-N quaternary system are mentioned

  14. Temperatures kept cool in Southampton.

    Science.gov (United States)

    McDonald, Katey

    2010-03-01

    According to Digitron, hospitals countrywide are seeing the benefits of DigiTrak, the company's automatic wireless temperature monitoring system. Katey McDonald, the company's marketing manager, outlines how the system replaces traditional methods of data collection by providing a single networked package, and describes its use at Southampton General Hospital for blood monitoring, with the help of advanced biomedical scientist and quality officer there Marie Cundall.

  15. Temperature measurement in nuclear environment

    International Nuclear Information System (INIS)

    Degas, P.

    1986-12-01

    Some criterions, that the used sensors have to follow, are given together with the conditions they may encountered. They may be used in irradiation or safety test devices, in experiments concerning mock-up or plant element, or even in nuclear plants themselves. The most suitable sensor type are mentioned, with their characteristics and their fiability. Two use examples of temperature probes are given, chosen to illustrate two sensor types: thermocouples in Superphenix-1 and platinum resistance probes in research reactor Orphee [fr

  16. On relativistic transformation of temperature

    Czech Academy of Sciences Publication Activity Database

    Mareš, Jiří J.; Hubík, Pavel; Špička, Václav

    2017-01-01

    Roč. 65, č. 6-8 (2017), 1-13, č. článku 1700018. ISSN 0015-8208 Institutional support: RVO:68378271 Keywords : Special theory of relativity * phenomenological temperature * Planck-Ott imbroglio * principle of equivalence of heat and work Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 2.434, year: 2016

  17. High-temperature geothermal cableheads

    Science.gov (United States)

    Coquat, J. A.; Eifert, R. W.

    1981-11-01

    Two high temperature, corrosion resistant logging cable heads which use metal seals and a stable fluid to achieve proper electrical terminations and cable sonde interfacings are described. A tensile bar provides a calibrated yield point, and a cone assembly anchors the cable armor to the head. Electrical problems of the sort generally ascribable to the cable sonde interface were absent during demonstration hostile environment loggings in which these cable heads were used.

  18. Temperature manipulation during layer chick embryogenesis

    NARCIS (Netherlands)

    Walstra, I.; Napel, ten J.; Kemp, B.; Brand, van den H.

    2010-01-01

    The current study investigated the effects of temperature manipulation (TM) during late embryogenesis on temperature preference, response to high environmental temperature, behavior, and performance in young layer chicks. Control (CC) embryos (n = 96) were incubated at 37.8°C eggshell temperature

  19. Daily temperature variations on Mars

    Science.gov (United States)

    Ditteon, R.

    1982-01-01

    It is noted that for approximately 32% of the Martian surface area no values of thermal inertia or albedo can fit the thermal observations. These temperature anomalies do not correlate with elevation, geologic units, morphology, or atmospheric dust content. All regions having a Lambert albedo less than 0.18 can be well fit with the standard thermal model, but all areas with albedo greater than 0.28 are anomalous. A strong inverse correlation is seen between the magnitude of the anomaly and the thermal inertia. This correlation is seen as indicating that some surface property is responsible for the anomaly. In the anomalous region the temperatures are observed to be warmer in the morning and cooler late in the afternoon and to decrease more slowly during the night than the Viking model temperatures. It is believed that of all the physical processes likely to occur on Mars but not included in the Viking thermal model, only a layered soil can explain the observations. A possible explanation of the layering deduced from the infrared thermal mapper observations is a layer of aeolian deposited dust about one thermal skin depth thick (1 to 4 cm), covering a duricrust.

  20. High temperature PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jianlu; Xie, Zhong; Zhang, Jiujun; Tang, Yanghua; Song, Chaojie; Navessin, Titichai; Shi, Zhiqing; Song, Datong; Wang, Haijiang; Wilkinson, David P.; Liu, Zhong-Sheng; Holdcroft, Steven [Institute for Fuel Cell Innovation, National Research Council Canada, Vancouver, BC (Canada V6T 1W5)

    2006-10-06

    There are several compelling technological and commercial reasons for operating H{sub 2}/air PEM fuel cells at temperatures above 100{sup o}C. Rates of electrochemical kinetics are enhanced, water management and cooling is simplified, useful waste heat can be recovered, and lower quality reformed hydrogen may be used as the fuel. This review paper provides a concise review of high temperature PEM fuel cells (HT-PEMFCs) from the perspective of HT-specific materials, designs, and testing/diagnostics. The review describes the motivation for HT-PEMFC development, the technology gaps, and recent advances. HT-membrane development accounts for {approx}90% of the published research in the field of HT-PEMFCs. Despite this, the status of membrane development for high temperature/low humidity operation is less than satisfactory. A weakness in the development of HT-PEMFC technology is the deficiency in HT-specific fuel cell architectures, test station designs, and testing protocols, and an understanding of the underlying fundamental principles behind these areas. The development of HT-specific PEMFC designs is of key importance that may help mitigate issues of membrane dehydration and MEA degradation. (author)

  1. Summary: High Temperature Downhole Motor

    Energy Technology Data Exchange (ETDEWEB)

    Raymond, David W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-10-01

    Directional drilling can be used to enable multi-lateral completions from a single well pad to improve well productivity and decrease environmental impact. Downhole rotation is typically developed with a motor in the Bottom Hole Assembly (BHA) that develops drilling power (speed and torque) necessary to drive rock reduction mechanisms (i.e., the bit) apart from the rotation developed by the surface rig. Historically, wellbore deviation has been introduced by a “bent-sub,” located in the BHA, that introduces a small angular deviation, typically less than 3 degrees, to allow the bit to drill off-axis with orientation of the BHA controlled at the surface. The development of a high temperature downhole motor would allow reliable use of bent subs for geothermal directional drilling. Sandia National Laboratories is pursuing the development of a high temperature motor that will operate on either drilling fluid (water-based mud) or compressed air to enable drilling high temperature, high strength, fractured rock. The project consists of designing a power section based upon geothermal drilling requirements; modeling and analysis of potential solutions; and design, development and testing of prototype hardware to validate the concept. Drilling costs contribute substantially to geothermal electricity production costs. The present development will result in more reliable access to deep, hot geothermal resources and allow preferential wellbore trajectories to be achieved. This will enable development of geothermal wells with multi-lateral completions resulting in improved geothermal resource recovery, decreased environmental impact and enhanced well construction economics.

  2. Supersymmetry breaking at finite temperature

    International Nuclear Information System (INIS)

    Kratzert, K.

    2002-11-01

    The mechanism of supersymmetry breaking at finite temperature is still only partly understood. Though it has been proven that temperature always breaks supersymmetry, the spontaneous nature of this breaking remains unclear, in particular the role of the Goldstone fermion. The aim of this work is to unify two existing approaches to the subject. From a hydrodynamic point of view, it has been argued under very general assumptions that in any supersymmetric quantum field theory at finite temperature there should exist a massless fermionic collective excitation, named phonino because of the analogy to the phonon. In the framework of a self-consistent resummed perturbation theory, it is shown for the example of the Wess-Zumino model that this mode fits very well into the quantum field theoretical framework pursued by earlier works. Interpreted as a bound state of boson and fermion, it contributes to the supersymmetric Ward-Takahashi identities in a way showing that supersymmetry is indeed broken spontaneously with the phonino playing the role of the Goldstone fermion. The second part of the work addresses the case of supersymmetric quantum electrodynamics. It is shown that also here the phonino exists and must be interpreted as the Goldstone mode. This knowledge allows a generalization to a wider class of models. (orig.)

  3. NSTX High Temperature Sensor Systems

    International Nuclear Information System (INIS)

    McCormack, B.; Kugel, H.W.; Goranson, P.; Kaita, R.

    1999-01-01

    The design of the more than 300 in-vessel sensor systems for the National Spherical Torus Experiment (NSTX) has encountered several challenging fusion reactor diagnostic issues involving high temperatures and space constraints. This has resulted in unique miniature, high temperature in-vessel sensor systems mounted in small spaces behind plasma facing armor tiles, and they are prototypical of possible high power reactor first-wall applications. In the Center Stack, Divertor, Passive Plate, and vessel wall regions, the small magnetic sensors, large magnetic sensors, flux loops, Rogowski Coils, thermocouples, and Langmuir Probes are qualified for 600 degrees C operation. This rating will accommodate both peak rear-face graphite tile temperatures during operations and the 350 degrees C bake-out conditions. Similar sensor systems including flux loops, on other vacuum vessel regions are qualified for 350 degrees C operation. Cabling from the sensors embedded in the graphite tiles follows narrow routes to exit the vessel. The detailed sensor design and installation methods of these diagnostic systems developed for high-powered ST operation are discussed

  4. Global predictability of temperature extremes

    Science.gov (United States)

    Coughlan de Perez, Erin; van Aalst, Maarten; Bischiniotis, Konstantinos; Mason, Simon; Nissan, Hannah; Pappenberger, Florian; Stephens, Elisabeth; Zsoter, Ervin; van den Hurk, Bart

    2018-05-01

    Extreme temperatures are one of the leading causes of death and disease in both developed and developing countries, and heat extremes are projected to rise in many regions. To reduce risk, heatwave plans and cold weather plans have been effectively implemented around the world. However, much of the world’s population is not yet protected by such systems, including many data-scarce but also highly vulnerable regions. In this study, we assess at a global level where such systems have the potential to be effective at reducing risk from temperature extremes, characterizing (1) long-term average occurrence of heatwaves and coldwaves, (2) seasonality of these extremes, and (3) short-term predictability of these extreme events three to ten days in advance. Using both the NOAA and ECMWF weather forecast models, we develop global maps indicating a first approximation of the locations that are likely to benefit from the development of seasonal preparedness plans and/or short-term early warning systems for extreme temperature. The extratropics generally show both short-term skill as well as strong seasonality; in the tropics, most locations do also demonstrate one or both. In fact, almost 5 billion people live in regions that have seasonality and predictability of heatwaves and/or coldwaves. Climate adaptation investments in these regions can take advantage of seasonality and predictability to reduce risks to vulnerable populations.

  5. Satellite Global and Hemispheric Lower Tropospheric Temperature Annual Temperature Cycle

    Directory of Open Access Journals (Sweden)

    Michael A. Brunke

    2010-11-01

    Full Text Available Previous analyses of the Earth’s annual cycle and its trends have utilized surface temperature data sets. Here we introduce a new analysis of the global and hemispheric annual cycle using a satellite remote sensing derived data set during the period 1979–2009, as determined from the lower tropospheric (LT channel of the MSU satellite. While the surface annual cycle is tied directly to the heating and cooling of the land areas, the tropospheric annual cycle involves additionally the gain or loss of heat between the surface and atmosphere. The peak in the global tropospheric temperature in the 30 year period occurs on 10 July and the minimum on 9 February in response to the larger land mass in the Northern Hemisphere. The actual dates of the hemispheric maxima and minima are a complex function of many variables which can change from year to year thereby altering these dates.Here we examine the time of occurrence of the global and hemispheric maxima and minima lower tropospheric temperatures, the values of the annual maxima and minima, and the slopes and significance of the changes in these metrics.  The statistically significant trends are all relatively small. The values of the global annual maximum and minimum showed a small, but significant trend. Northern and Southern Hemisphere maxima and minima show a slight trend toward occurring later in the year. Most recent analyses of trends in the global annual cycle using observed surface data have indicated a trend toward earlier maxima and minima.

  6. Fiber Optic Temperature Sensor Insert for High Temperature Environments

    Science.gov (United States)

    Black, Richard James (Inventor); Costa, Joannes M. (Inventor); Moslehi, Behzad (Inventor); Zarnescu, Livia (Inventor)

    2017-01-01

    A thermal protection system (TPS) test plug has optical fibers with FBGs embedded in the optical fiber arranged in a helix, an axial fiber, and a combination of the two. Optionally, one of the optical fibers is a sapphire FBG for measurement of the highest temperatures in the TPS plug. The test plug may include an ablating surface and a non-ablating surface, with an engagement surface with threads formed, the threads having a groove for placement of the optical fiber. The test plug may also include an optical connector positioned at the non-ablating surface for protection of the optical fiber during insertion and removal.

  7. Apparatus Would Measure Temperatures Of Ball Bearings

    Science.gov (United States)

    Gibson, John C.; Fredricks, Thomas H.

    1995-01-01

    Rig for testing ball bearings under radial and axial loads and measuring surface temperatures undergoing development. Includes extensible thermocouples: by means of bellows as longitudinal positioners, thermocouples driven into contact with bearing balls to sense temperatures immediately after test run. Not necessary to disassemble rig or to section balls to obtain indirect indications of maximum temperatures reached. Thermocouple measurements indicate temperatures better than temperature-sensitive paints.

  8. Inflight fuel tank temperature survey data

    Science.gov (United States)

    Pasion, A. J.

    1979-01-01

    Statistical summaries of the fuel and air temperature data for twelve different routes and for different aircraft models (B747, B707, DC-10 and DC-8), are given. The minimum fuel, total air and static air temperature expected for a 0.3% probability were summarized in table form. Minimum fuel temperature extremes agreed with calculated predictions and the minimum fuel temperature did not necessarily equal the minimum total air temperature even for extreme weather, long range flights.

  9. Quantifying Temperature Effects on Fall Chinook Salmon

    Energy Technology Data Exchange (ETDEWEB)

    Jager, Yetta [ORNL

    2011-11-01

    The motivation for this study was to recommend relationships for use in a model of San Joaquin fall Chinook salmon. This report reviews literature pertaining to relationships between water temperature and fall Chinook salmon. The report is organized into three sections that deal with temperature effects on development and timing of freshwater life stages, temperature effects on incubation survival for eggs and alevin, and temperature effects on juvenile survival. Recommendations are made for modeling temperature influences for all three life stages.

  10. Flexible PVDF ferroelectric capacitive temperature sensor

    KAUST Repository

    Khan, Naveed

    2015-08-02

    In this paper, a capacitive temperature sensor based on polyvinylidene fluoride (PVDF) capacitor is explored. The PVDF capacitor is characterized below its Curie temperature. The capacitance of the PVDF capacitor changes vs temperature with a sensitivity of 16pF/°C. The linearity measurement of the capacitance-temperature relation shows less than 0.7°C error from a best fit straight line. An LC oscillator based temperature sensor is demonstrated based on this capacitor.

  11. Temperature compensation and entrainment in circadian rhythms

    International Nuclear Information System (INIS)

    Bodenstein, C; Heiland, I; Schuster, S

    2012-01-01

    To anticipate daily variations in the environment and coordinate biological activities into a daily cycle many organisms possess a circadian clock. In the absence of external time cues the circadian rhythm persists with a period of approximately 24 h. The clock phase can be shifted by single pulses of light, darkness, chemicals, or temperature and this allows entrainment of the clock to exactly 24 h by cycles of these zeitgebers. On the other hand, the period of the circadian rhythm is kept relatively constant within a physiological range of constant temperatures, which means that the oscillator is temperature compensated. The mechanisms behind temperature compensation and temperature entrainment are not fully understood, neither biochemically nor mathematically. Here, we theoretically investigate the interplay of temperature compensation and entrainment in general oscillatory systems. We first give an analytical treatment for small temperature shifts and derive that every temperature-compensated oscillator is entrainable to external small-amplitude temperature cycles. Temperature compensation ensures that this entrainment region is always centered at the endogenous period regardless of possible seasonal temperature differences. Moreover, for small temperature cycles the entrainment region of the oscillator is potentially larger for rectangular pulses. For large temperature shifts we numerically analyze different circadian clock models proposed in the literature with respect to these properties. We observe that for such large temperature shifts sinusoidal or gradual temperature cycles allow a larger entrainment region than rectangular cycles. (paper)

  12. Localized temperature stability in Low Temperature Cofired Ceramics (LTCC).

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Steven Xunhu; Hsieh, Lung-Hwa.

    2012-04-01

    The base dielectrics of commercial low temperature cofired ceramics (LTCC) systems have a temperature coefficient of resonant frequency ({tau}{sub f}) in the range -50 {approx} -80 ppm/C. In this research we explored a method to realize zero or near zero {tau}{sub f} resonators by incorporating {tau}{sub f} compensating materials locally into a multilayer LTCC structure. To select composition for {tau}{sub f} adjustment, {tau}{sub f} compensating materials with different amount of titanates were formulated, synthesized, and characterized. Chemical interactions and physical compatibility between the {tau}{sub f} modifiers and the host LTCC dielectrics were investigated. Studies on stripline (SL) resonator panels with multiple compensating dielectrics revealed that: 1) compositions using SrTiO{sub 3} provide the largest {tau}{sub f} adjustment among titanates, 2) the {tau}{sub f} compensation is proportional to the amount of SrTiO{sub 3} in compensating materials, as well as the thickness of the compensating layer, and 3) the most effective {tau}{sub f} compensation is achieved when the compensating dielectric is integrated next to the SL. Using the effective dielectric constant of a heterogeneous layered dielectric structure, results from Method of Momentum (MoM) electromagnetic simulations are consistent with the experimental observations.

  13. High temperature superconductivity the road to higher critical temperature

    CERN Document Server

    Uchida, Shin-ichi

    2015-01-01

    This book presents an overview of material-specific factors that influence Tc and give rise to diverse Tc values for copper oxides and iron-based high- Tc superconductors on the basis of more than 25 years of experimental data, to most of which the author has made important contributions. The book then explains why both compounds are distinct from others with similar crystal structure and whether or not one can enhance Tc, which in turn gives a hint on the unresolved pairing mechanism. This is an unprecedented new approach to the problem of high-temperature superconductivity and thus will be inspiring to both specialists and non-specialists interested in this field.   Readers will receive in-depth information on the past, present, and future of high-temperature superconductors, along with special, updated information on what the real highest Tc values are and particularly on the possibility of enhancing Tc for each member material, which is important for application. At this time, the highest Tc has not been...

  14. Modern high-temperature superconductivity

    International Nuclear Information System (INIS)

    Ching Wu Chu

    1988-01-01

    Ever since the discovery of superconductivity in 1911, its unusual scientific challenge and great technological potential have been recognized. For the past three-quarters of a century, superconductivity has done well on the science front. This is because sueprconductivity is interesting not only just in its own right but also in its ability to act as a probe to many exciting nonsuperconducting phenomena. For instance, it has continued to provide bases for vigorous activities in condensed matter science. Among the more recent examples are heavy-fermion systems and organic superconductors. During this same period of time, superconductivity has also performed admirably in the applied area. Many ideas have been conceived and tested, making use of the unique characteristics of superconductivity - zero resistivity, quantum interference phenomena, and the Meissner effect. In fact, it was not until late January 1987 that it became possible to achieve superconductivity with the mere use of liquid nitrogen - which is plentiful, cheap, efficient, and easy to handle - following the discovery of supercondictivity above 90 K in Y-Ba-Cu-O, the first genuine quaternary superconductor. Superconductivity above 90 K poses scientific and technological challenges not previously encountered: no existing theories can adequately describe superconductivity above 40 K and no known techniques can economically process the materials for full-scale applications. In this paper, therefore, the author recalls a few events leading to the discovery of the new class of quaternary compounds with a superconducting transition temperature T c in the 90 K range, describes the current experimental status of high-temperature superconductivity and, finally, discusses the prospect of very-high-temperature superconductivity, i.e., with a T c substantially higher than 100 K. 97 refs., 7 figs

  15. Passivation of high temperature superconductors

    Science.gov (United States)

    Vasquez, Richard P. (Inventor)

    1991-01-01

    The surface of high temperature superconductors such as YBa2Cu3O(7-x) are passivated by reacting the native Y, Ba and Cu metal ions with an anion such as sulfate or oxalate to form a surface film that is impervious to water and has a solubility in water of no more than 10(exp -3) M. The passivating treatment is preferably conducted by immersing the surface in dilute aqueous acid solution since more soluble species dissolve into the solution. The treatment does not degrade the superconducting properties of the bulk material.

  16. Mechanism for elevated temperature leaching

    International Nuclear Information System (INIS)

    Kenna, B.T.; Murphy, K.D.

    1979-01-01

    Long-term, elevated temperature leaching and subsequent electron microprobe analysis of simulated waste glass and ceramic materials have been completed. A cyclic leaching pattern was found in all systems over a 20-month period. It appears that the leaching of mobile ions by simple diffusional processes is modified by more complex chemical interactions. The release of immobile ions is primarily a function of their chemical interactions in the matrix which suggests that these ions may be complex species when released into solution. A mechanism is proposed which incorporates these ideas and the cyclic phenomenon observed

  17. Temperature Modulated Nanomechanical Thermal Analysis

    DEFF Research Database (Denmark)

    Alves, Gustavo Marcati A.; Bose-Goswami, Sanjukta; Mansano, Ronaldo D.

    2018-01-01

    The response of microcantilever deflection to complex heating profiles was used to study thermal events like glass transition and enthalpy relaxation on nanograms of the biopolymer Poly(lactic-co-glycolic acid) (PLGA). The use of two heating rates enables the separation of effects on the deflection...... response that depends on previous thermal history (non-reversing signal) and effects that depends only on the heating rate variation (reversing signal). As these effects may appear superposed in the total response, temperature modulation can increase the measurement sensitivity to some thermal events when...

  18. CONFINEMENT OF HIGH TEMPERATURE PLASMA

    Science.gov (United States)

    Koenig, H.R.

    1963-05-01

    The confinement of a high temperature plasma in a stellarator in which the magnetic confinement has tended to shift the plasma from the center of the curved, U-shaped end loops is described. Magnetic means are provided for counteracting this tendency of the plasma to be shifted away from the center of the end loops, and in one embodiment this magnetic means is a longitudinally extending magnetic field such as is provided by two sets of parallel conductors bent to follow the U-shaped curvature of the end loops and energized oppositely on the inside and outside of this curvature. (AEC)

  19. Ammonia synthesis at low temperatures

    DEFF Research Database (Denmark)

    Rod, Thomas Holm; Logadottir, Ashildur; Nørskov, Jens Kehlet

    2000-01-01

    have been carried out to evaluate its feasibility. The calculations suggest that it might be possible to catalytically produce ammonia from molecular nitrogen at low temperatures and pressures, in particular if energy is fed into the process electrochemically. (C) 2000 American Institute of Physics.......Density functional theory (DFT) calculations of reaction paths and energies for the industrial and the biological catalytic ammonia synthesis processes are compared. The industrial catalyst is modeled by a ruthenium surface, while the active part of the enzyme is modeled by a MoFe6S9 complex...

  20. High temperature superconductors and method

    International Nuclear Information System (INIS)

    Ruvalds, J.J.

    1977-01-01

    This invention comprises a superconductive compound having the formula: Ni/sub 1-x/M/sub x/Z/sub y/ wherein M is a metal which will destroy the magnetic character of nickel (preferably copper, silver or gold); Z is hydrogen or deuterium; x is 0.1 to 0.9; and y, correspondingly, 0.9 to 0.1, and method of conducting electric current with no resistance at relatively high temperature of T>1 0 K comprising a conductor consisting essentially of the superconducting compound noted above

  1. High temperature internal friction in pure aluminium

    International Nuclear Information System (INIS)

    Aboagye, J.K.; Payida, D.S.

    1982-05-01

    The temperature dependence of internal friction of nearly pure aluminium (99.99% aluminium) has been carefully measured as a function of annealing temperature and hence grain size. The results indicate that, provided the frequency and annealing temperature are held constant, the internal friction increases with temperature until some maximum value is attained and then begins to go down as the temperature is further increased. It is also noted that the internal friction decreases with annealing temperature and that annealing time has the same effect as annealing temperature. It is also noted that the internal friction peak is shifted towards higher temperatures as annealing temperature is increased. It is surmised that the grain size or the total grain boundary volume determines the height of the internal friction curve and that the order-disorder transitions at the grain boundaries induced by both entropy and energy gradients give rise to internal friction peaks in polycrystals. (author)

  2. Spin Hall magnetoresistance at high temperatures

    International Nuclear Information System (INIS)

    Uchida, Ken-ichi; Qiu, Zhiyong; Kikkawa, Takashi; Iguchi, Ryo; Saitoh, Eiji

    2015-01-01

    The temperature dependence of spin Hall magnetoresistance (SMR) in Pt/Y 3 Fe 5 O 12 (YIG) bilayer films has been investigated in a high temperature range from room temperature to near the Curie temperature of YIG. The experimental results show that the magnitude of the magnetoresistance ratio induced by the SMR monotonically decreases with increasing the temperature and almost disappears near the Curie temperature. We found that, near the Curie temperature, the temperature dependence of the SMR in the Pt/YIG film is steeper than that of a magnetization curve of the YIG; the critical exponent of the magnetoresistance ratio is estimated to be 0.9. This critical behavior of the SMR is attributed mainly to the temperature dependence of the spin-mixing conductance at the Pt/YIG interface

  3. Distributed temperature sensor testing in liquid sodium

    Energy Technology Data Exchange (ETDEWEB)

    Gerardi, Craig, E-mail: cgerardi@anl.gov; Bremer, Nathan; Lisowski, Darius; Lomperski, Stephen

    2017-02-15

    Highlights: • Distributed temperature sensors measured high-resolution liquid-sodium temperatures. • DTSs worked well up to 400 °C. • A single DTS simultaneously detected sodium level and temperature. - Abstract: Rayleigh-backscatter-based distributed fiber optic sensors were immersed in sodium to obtain high-resolution liquid-sodium temperature measurements. Distributed temperature sensors (DTSs) functioned well up to 400 °C in a liquid sodium environment. The DTSs measured sodium column temperature and the temperature of a complex geometrical pattern that leveraged the flexibility of fiber optics. A single Ø 360 μm OD sensor registered dozens of temperatures along a length of over one meter at 100 Hz. We also demonstrated the capability to use a single DTS to simultaneously detect thermal interfaces (e.g. sodium level) and measure temperature.

  4. Managing Temperature Effects in Nanoscale Adaptive Systems

    CERN Document Server

    Wolpert, David

    2012-01-01

    This book discusses new techniques for detecting, controlling, and exploiting the impacts of temperature variations on nanoscale circuits and systems.  It provides a holistic discussion of temperature management, including physical phenomena (reversal of the MOSFET temperature dependence) that have recently become problematic, along with circuit techniques for detecting, controlling, and adapting to these phenomena. A detailed discussion is also included of the general aspects of thermal-aware system design and management of temperature-induced faults. A new sensor system is described that can determine the temperature dependence as well as the operating temperature to improve system reliability.  A new method is presented to control a circuit’s temperature dependence by individually tuning pull-up and pull-down networks to their temperature-insensitive operating points. This method extends the range of supply voltages that can be made temperature-insensitive, achieving insensitivity at nominal voltage fo...

  5. Formation temperatures of thermogenic and biogenic methane

    Science.gov (United States)

    Stolper, D.A.; Lawson, M.; Davis, C.L.; Ferreira, A.A.; Santos Neto, E. V.; Ellis, G.S.; Lewan, M.D.; Martini, Anna M.; Tang, Y.; Schoell, M.; Sessions, A.L.; Eiler, J.M.

    2014-01-01

    Methane is an important greenhouse gas and energy resource generated dominantly by methanogens at low temperatures and through the breakdown of organic molecules at high temperatures. However, methane-formation temperatures in nature are often poorly constrained. We measured formation temperatures of thermogenic and biogenic methane using a “clumped isotope” technique. Thermogenic gases yield formation temperatures between 157° and 221°C, within the nominal gas window, and biogenic gases yield formation temperatures consistent with their comparatively lower-temperature formational environments (<50°C). In systems where gases have migrated and other proxies for gas-generation temperature yield ambiguous results, methane clumped-isotope temperatures distinguish among and allow for independent tests of possible gas-formation models.

  6. Evaluation of high temperature pressure sensors

    International Nuclear Information System (INIS)

    Choi, In-Mook; Woo, Sam-Yong; Kim, Yong-Kyu

    2011-01-01

    It is becoming more important to measure the pressure in high temperature environments in many industrial fields. However, there is no appropriate evaluation system and compensation method for high temperature pressure sensors since most pressure standards have been established at room temperature. In order to evaluate the high temperature pressure sensors used in harsh environments, such as high temperatures above 250 deg. C, a specialized system has been constructed and evaluated in this study. The pressure standard established at room temperature is connected to a high temperature pressure sensor through a chiller. The sensor can be evaluated in conditions of changing standard pressures at constant temperatures and of changing temperatures at constant pressures. According to the evaluation conditions, two compensation methods are proposed to eliminate deviation due to sensitivity changes and nonlinear behaviors except thermal hysteresis.

  7. Thermal-hydraulic calculation methods for transients and accidents of the reactor cooling system under special consideration of multi-dimensional flows (ATHLET, FLUBOX, CFX). Final report; Thermohydraulische Rechenmethoden zu Transienten und Stoerfaellen im Reaktorkuehlkreislauf unter besonderer Beruecksichtigung mehrdimensionaler Stroemungen (ATHLET, FLUBOX, CFX). Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Glaeser, H.; Graf, U.; Herb, J.; and others

    2012-02-15

    models have been developed in the frame of further development of ATHLET. The descriptions of these models are provided in the report. The commercial CFX code solves the three-dimensional conservation equations for mass, momentum and energy. The most important physical models in a CFD code for reactor safety applications are the turbulence and multi-phase models. In order to calculate the turbulent transport terms in the averaged conservation equations for momentum and energy, many turbulence models are available. The variety of physical models, to be selected by the code user, range from turbulent one-phase flows up to two-phase flows and mass and heat transfer at the interface. Within this project, available turbulence and two-phase models in ANSYS CFX suitable for reactor-typical transients and detached flows combined with heat transfer were validated and adjusted. If necessary, new models were implemented and tested. The method for uncertainty evaluation of computer code results proposed by GRS is used in many countries and organisations in the meantime. The method is also applied in many licensing cases of nuclear plants. Some extensions of the method were investigated and are proposed. These address two problem areas: 1. Treatment of epistemic and aleatory uncertainties 2. Uncertainty and sensitivity analysis under special consideration of dependences between uncertain input parameters. In the frame of the international OECD/CSNI programme ''Safety Margin Application and Assessment (SM2A)'', GRS performed uncertainty and sensitivity analyses of the results of the thermal-hydraulic computer code ATHLET. The investigated scenario was a steam line break of the pressurized water reactor Zion in USA. The effect of variations of uncertain input parameters on the maximum cladding temperature is significant for the identified relevant event sequences. That result demonstrates the importance of uncertainty analyses.

  8. Temperature influences on growth of aquatic organisms

    International Nuclear Information System (INIS)

    Coutant, C.C.; Suffern, J.S.

    1977-01-01

    Temperature profoundly affects the growth rates of aquatic organisms, and its control is essential for effective aquaculture. Characteristically, both low and high temperatures produce slow growth rates and inefficient food conversion, while intermediate temperature ranges provide rapid growth and efficient food conversion. Distinct, species-specific optimum temperatures and upper and lower temperatures of zero growth can often be defined. Thermal effects can be greatly modified by amounts and quality of food. These data not only provide the basis for criteria which maintain growth of wild organisms but also for effectively using waste heat to create optimal conditions of temperature and food ration for growing aquatic organisms commercially

  9. Distributed temperature sensor testing in liquid sodium

    Energy Technology Data Exchange (ETDEWEB)

    Gerardi, Craig; Bremer, Nathan; Lisowski, Darius; Lomperski, Stephen

    2017-02-01

    Rayleigh-backscatter-based distributed fiber optic sensors were immersed in sodium to obtain high-resolution liquid-sodium temperature measurements. Distributed temperature sensors (DTSs) functioned well up to 400°C in a liquid sodium environment. The DTSs measured sodium column temperature and the temperature of a complex geometrical pattern that leveraged the flexibility of fiber optics. A single Ø 360 lm OD sensor registered dozens of temperatures along a length of over one meter at 100 Hz. We also demonstrated the capability to use a single DTS to simultaneously detect thermal interfaces (e.g. sodium level) and measure temperature.

  10. Temperature-Controlled Chameleonlike Cloak

    Science.gov (United States)

    Peng, Ruiguang; Xiao, Zongqi; Zhao, Qian; Zhang, Fuli; Meng, Yonggang; Li, Bo; Zhou, Ji; Fan, Yuancheng; Zhang, Peng; Shen, Nian-Hai; Koschny, Thomas; Soukoulis, Costas M.

    2017-01-01

    Invisibility cloaking based on transformation optics has brought about unlimited space for reverie. However, the design and fabrication of transformation-optics-based cloaks still remain fairly challenging because of the complicated, even extreme, material prescriptions, including its meticulously engineered anisotropy, inhomogeneity and singularity. And almost all the state-of-the-art cloaking devices work within a narrow and invariable frequency band. Here, we propose a novel mechanism for all-dielectric temperature-controllable cloaks. A prototype device was designed and fabricated with SrTiO3 ferroelectric cuboids as building blocks, and its cloaking effects were successfully demonstrated, including its frequency-agile invisibility by varying temperature. It revealed that the predesignated cloaking device based on our proposed strategy could be directly scaled in dimensions to operate at different frequency regions, without the necessity for further efforts of redesign. Our work opens the door towards the realization of tunable cloaking devices for various practical applications and provides a simple strategy to readily extend the cloaking band from microwave to terahertz regimes without the need for reconfiguration.

  11. Studies of high temperature superconductors

    International Nuclear Information System (INIS)

    Narlikar, A.

    1989-01-01

    The high temperature superconductors (HTSCs) discovered are from the family of ceramic oxides. Their large scale utilization in electrical utilities and in microelectronic devices are the frontal challenges which can perhaps be effectively met only through consolidated efforts and expertise of a multidisciplinary nature. During the last two years the growth of the new field has occurred on an international scale and perhaps has been more rapid than in most other fields. There has been an extraordinary rush of data and results which are continually being published as short texts dispersed in many excellent journals, some of which were started to ensure rapid publication exclusively in this field. As a result, the literature on HTSCs has indeed become so massive and so diffuse that it is becoming increasingly difficult to keep abreast with the important and reliable facets of this fast-growing field. This provided the motivation to evolve a process whereby both professional investigators and students can have ready access to up-to- date in-depth accounts of major technical advances happening in this field. The present series Studies of High Temperature Superconductors has been launched to, at least in part, fulfill this need

  12. Temperature-Controlled Chameleonlike Cloak

    Directory of Open Access Journals (Sweden)

    Ruiguang Peng

    2017-03-01

    Full Text Available Invisibility cloaking based on transformation optics has brought about unlimited space for reverie. However, the design and fabrication of transformation-optics-based cloaks still remain fairly challenging because of the complicated, even extreme, material prescriptions, including its meticulously engineered anisotropy, inhomogeneity and singularity. And almost all the state-of-the-art cloaking devices work within a narrow and invariable frequency band. Here, we propose a novel mechanism for all-dielectric temperature-controllable cloaks. A prototype device was designed and fabricated with SrTiO_{3} ferroelectric cuboids as building blocks, and its cloaking effects were successfully demonstrated, including its frequency-agile invisibility by varying temperature. It revealed that the predesignated cloaking device based on our proposed strategy could be directly scaled in dimensions to operate at different frequency regions, without the necessity for further efforts of redesign. Our work opens the door towards the realization of tunable cloaking devices for various practical applications and provides a simple strategy to readily extend the cloaking band from microwave to terahertz regimes without the need for reconfiguration.

  13. The Low Temperature CFB Gasifier

    DEFF Research Database (Denmark)

    Stoholm, P.; Nielsen, Rasmus Glar; Richardt, K.

    2004-01-01

    straw, animal manure and waste and for co-firing the product gas in existing, e.g. coal fired power plant boilers. The aim is to prevent fouling, agglomeration and high temperature corrosion caused by potassium and chlorine and other fuel components when producing electricity. So far 92 hours......The Low Temperature Circulating Fluidised Bed (LT-CFB) gasification process is described together with the 50 kW and the 500 kW test plants and latest test results. The LT-CFB process is especially developed for medium and large scale (few to >100 MW) gasification of problematic bio-fuels like...... of experiments with the 50 kW test plant with two extremely difficult types of straw has shown low char losses and high retentions of ash including e.g. potassium. Latest 27 hours of experiments with dried, high ash pig- and hen manure has further indicated the concepts high fuel flexibility. The new 500 kW test...

  14. High temperature superconductor current leads

    International Nuclear Information System (INIS)

    Zeimetz, B.; Liu, H.K.; Dou, S.X.

    1996-01-01

    Full text: The use of superconductors in high electrical current applications (magnets, transformers, generators etc.) usually requires cooling with liquid Helium, which is very expensive. The superconductor itself produces no heat, and the design of Helium dewars is very advanced. Therefore most of the heat loss, i.e. Helium consumption, comes from the current lead which connects the superconductor with its power source at room temperature. The current lead usually consists of a pair of thick copper wires. The discovery of the High Temperature Superconductors makes it possible to replace a part of the copper with superconducting material. This drastically reduces the heat losses because a) the superconductor generates no resistive heat and b) it is a very poor thermal conductor compared with the copper. In this work silver-sheathed superconducting tapes are used as current lead components. The work comprises both the production of the tapes and the overall design of the leads, in order to a) maximize the current capacity ('critical current') of the superconductor, b) minimize the thermal conductivity of the silver clad, and c) optimize the cooling conditions

  15. Container floor at high temperatures

    International Nuclear Information System (INIS)

    Reutler, H.; Klapperich, H.J.; Mueller-Frank, U.

    1978-01-01

    The invention describes a floor for container which is stressed at high, changing temperatures and is intended for use in gas-cooled nuclear reactors. Due to the downward cooling gas flow in these types of reactor, the reactor floor is subjected to considerable dimensional changes during switching on and off. In the heating stage, the whole graphite structure of the reactor core and floor expands. In order to avoid arising constraining forces, sufficiently large expansion spaces must be allowed for furthermore restoring forces must be present to close the gaps again in the cooling phase. These restoring forces must be permanently present to prevent loosening of the core cuits amongst one another and thus uncontrollable relative movement. Spring elements are not suitable due to fast fatigue as a result of high temperatures and radiation exposure. It is suggested to have the floor elements supported on rollers whose rolling planes are downwards inclined to a fixed point for support. The construction is described in detail by means of drawings. (GL) [de

  16. Wolte 5. low temperature electronics

    International Nuclear Information System (INIS)

    Balestra, F.; Dieudonne, F.; Jomaah, J.

    2002-01-01

    This book present the latest research and development results in advanced materials, technologies, devices, circuits and systems for low temperature electronics. The main themes of the papers are ranging from physics and fundamental aspects, modeling and simulation, to device and circuit design. The topics include advanced process and characterization, novel devices and cryogenic instrumentation. The papers are divided into nine sections, reflecting the main research efforts in different areas: i) deep submicron silicon MOSFETs, ii) alternative MOSFETs (SOI, innovating device architectures), iii) III-V devices, iv) other semiconductor devices (Ge devices, p-n junctions, IR sensors, semiconductor microcrystals), v) emerging devices and phenomena (nano Si-based devices, conduction and fluctuations mechanisms), vi) superconducting materials, vii) superconducting detectors, viii) superconducting devices and circuits (RSFQ, SIS mixers, metal-superconducting-semiconductor structures), ix) low temperature electronics for space applications. Six invited papers presented by internationally recognized authors, and 39 contributed papers are presented. The invited papers provide an excellent overview of today's status and progress, as well as tomorrow's challenges and trends in this important discipline for many cryogenic applications. (authors)

  17. Changing world extreme temperature statistics

    Science.gov (United States)

    Finkel, J. M.; Katz, J. I.

    2018-04-01

    We use the Global Historical Climatology Network--daily database to calculate a nonparametric statistic that describes the rate at which all-time daily high and low temperature records have been set in nine geographic regions (continents or major portions of continents) during periods mostly from the mid-20th Century to the present. This statistic was defined in our earlier work on temperature records in the 48 contiguous United States. In contrast to this earlier work, we find that in every region except North America all-time high records were set at a rate significantly (at least $3\\sigma$) higher than in the null hypothesis of a stationary climate. Except in Antarctica, all-time low records were set at a rate significantly lower than in the null hypothesis. In Europe, North Africa and North Asia the rate of setting new all-time highs increased suddenly in the 1990's, suggesting a change in regional climate regime; in most other regions there was a steadier increase.

  18. High Temperature Superconductor Accelerator Magnets

    CERN Document Server

    AUTHOR|(CDS)2079328; de Rijk, Gijs; Dhalle, Marc

    2016-11-10

    For future particle accelerators bending dipoles are considered with magnetic fields exceeding $20T$. This can only be achieved using high temperature superconductors (HTS). These exhibit different properties from classical low temperature superconductors and still require significant research and development before they can be applied in a practical accelerator magnet. In order to study HTS in detail, a five tesla demonstrator magnet named Feather-M2 is designed and constructed. The magnet is based on ReBCO coated conductor, which is assembled into a $10kA$ class Roebel cable. A new and optimized Aligned Block layout is used, which takes advantage of the anisotropy of the conductor. This is achieved by providing local alignment of the Roebel cable in the coil windings with the magnetic field lines. A new Network Model capable of analyzing transient electro-magnetic and thermal phenomena in coated conductor cables and coils is developed. This model is necessary to solve critical issues in coated conductor ac...

  19. The international surface temperature initiative

    Science.gov (United States)

    Thorne, P. W.; Lawrimore, J. H.; Willett, K. M.; Allan, R.; Chandler, R. E.; Mhanda, A.; de Podesta, M.; Possolo, A.; Revadekar, J.; Rusticucci, M.; Stott, P. A.; Strouse, G. F.; Trewin, B.; Wang, X. L.; Yatagai, A.; Merchant, C.; Merlone, A.; Peterson, T. C.; Scott, E. M.

    2013-09-01

    The aim of International Surface Temperature Initiative is to create an end-to-end process for analysis of air temperature data taken over the land surface of the Earth. The foundation of any analysis is the source data. Land surface air temperature records have traditionally been stored in local, organizational, national and international holdings, some of which have been available digitally but many of which are available solely on paper or as imaged files. Further, economic and geopolitical realities have often precluded open sharing of these data. The necessary first step therefore is to collate readily available holdings and augment these over time either through gaining access to previously unavailable digital data or through data rescue and digitization activities. Next, it must be recognized that these historical measurements were made primarily in support of real-time weather applications where timeliness and coverage are key. At almost every long-term station it is virtually certain that changes in instrumentation, siting or observing practices have occurred. Because none of the historical measures were made in a metrologically traceable manner there is no unambiguous way to retrieve the true climate evolution from the heterogeneous raw data holdings. Therefore it is desirable for multiple independent groups to produce adjusted data sets (so-called homogenized data) to adequately understand the data characteristics and estimate uncertainties. Then it is necessary to benchmark the performance of the contributed algorithms (equivalent to metrological software validation) through development of realistic benchmark datasets. In support of this, a series of successive benchmarking and assessment cycles are envisaged, allowing continual improvement while avoiding over-tuning of algorithms. Finally, a portal is proposed giving access to related data-products, utilizing the assessment results to provide guidance to end-users on which product is the most suited to

  20. The Influence of Air Temperature on the Dew Point Temperature in ...

    African Journals Online (AJOL)

    ADOWIE PERE

    done to determine the influence and effect of temperature on other climatic environmental ... Key words: Air Temperature, Dew point temperature, Weather, Climate, Influence. Weather ... humidity, clouds and atmospheric pressure. Its.

  1. Similar temperature dependencies of glycolytic enzymes : An evolutionary adaptation to temperature dynamics?

    NARCIS (Netherlands)

    Cruz, L.A.B.; Hebly, M.; Duong, G.H.; Wahl, S.A.; Pronk, J.T.; Heijnen, J.J.; Daran-Lapujade, P.; Van Gulik, W.M.

    2012-01-01

    Background Temperature strongly affects microbial growth, and many microorganisms have to deal with temperature fluctuations in their natural environment. To understand regulation strategies that underlie microbial temperature responses and adaptation, we studied glycolytic pathway kinetics in

  2. NOAA Global Surface Temperature (NOAAGlobalTemp)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Global Surface Temperature Dataset (NOAAGlobalTemp) is a merged land–ocean surface temperature analysis (formerly known as MLOST) (link is external). It is...

  3. GODAE, SFCOBS - Surface Temperature Observations, 1998-present

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — GODAE, SFCOBS - Surface Temperature Observations: Ship, fixed/drifting buoy, and CMAN in-situ surface temperature. Global Telecommunication System (GTS) Data. The...

  4. EOP TDRs (Temperature-Depth-Recordings) Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature-depth-recorders (TDRs) were attached to commercial longline and research Cobb trawl gear to obtain absolute depth and temperature measurement during...

  5. Resonance integral calculations for high temperature reactors

    International Nuclear Information System (INIS)

    Blake, J.P.H.

    1960-02-01

    Methods of calculation of resonance integrals of finite dilution and temperature are given for both, homogeneous and heterogeneous geometries, together with results obtained from these methods as applied to the design of high temperature reactors. (author)

  6. Platinum-Resistor Differential Temperature Sensor

    Science.gov (United States)

    Kolbly, R. B.; Britcliffe, M. J.

    1985-01-01

    Platinum resistance elements used in bridge circuit for measuring temperature difference between two flowing liquids. Temperature errors with circuit are less than 0.01 degrees C over range of 100 degrees C.

  7. Modelling global fresh surface water temperature

    NARCIS (Netherlands)

    Beek, L.P.H. van; Eikelboom, T.; Vliet, M.T.H. van; Bierkens, M.F.P.

    2011-01-01

    Temperature directly determines a range of water physical properties including vapour pressure, surface tension, density and viscosity, and the solubility of oxygen and other gases. Indirectly water temperature acts as a strong control on fresh water biogeochemistry, influencing sediment

  8. Design of a dynamic compensated temperature sensor

    International Nuclear Information System (INIS)

    Yan, Wu; Katz, E.M.; Kerlin, T.W.

    1991-01-01

    One important function of a temperature sensor in a nuclear power plant is to track changing process temperatures, but the sensor output lags the changing temperature. This lag may have a large influence when the sensor is used in control or safety systems. Therefore, it is advantageous to develop methods that increase the sensor response speed. The goal of this project is to develop a fast-responding temperature sensor, the dynamic compensated temperature sensor (DCTS), based on signal dynamic compensation technology. To verify the theoretical basis of the DCTS and incorporate the DCTS into a real temperature measurement process, several experiments have been performed. The DCTS is a simple approach that can decrease the temperature sensor's response time, and it can provide faster temperature signals to the nuclear power plant safety system

  9. Extended Reconstructed Sea Surface Temperature (ERSST)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Extended Reconstructed Sea Surface Temperature (ERSST) dataset is a global monthly sea surface temperature analysis derived from the International Comprehensive...

  10. The Low Temperature Microgravity Physics Facility Project

    Science.gov (United States)

    Chui, T.; Holmes, W.; Lai, A.; Croonquist, A.; Eraker, J.; Abbott, R.; Mills, G.; Mohl, J.; Craig, J.; Balachandra, B.; hide

    2000-01-01

    We describe the design and development of the Low Temperature Microgravity Physics Facility, which is intended to provide a unique environment of low temperature and microgravity for the scientists to perform breakthrough investigations on board the International Space Station.

  11. The high-temperature reactor

    International Nuclear Information System (INIS)

    Kirchner, U.

    1991-01-01

    The book deals with the development of the German high-temperature reactor (pebble-bed), the design of a prototype plant and its (at least provisional) shut-down in 1989. While there is a lot of material on the HTR's competitor, the fast breeder, literature is very incomplete on HTRs. The author describes HTR's history as a development which was characterised by structural divergencies but not effectively steered and monitored. There was no project-oriented 'community' such as there was for the fast breeder. Also, the new technology was difficult to control there were situations where no one quite knew what was going on. The technical conditions however were not taken as facts but as a basis for interpretation, wishes and reservations. The HTR gives an opportunity to consider the conditions under which large technical projects can be carried out today. (orig.) [de

  12. The Low temperature CFB gasifier

    DEFF Research Database (Denmark)

    Stoholm, P.; Nielsen, Rasmus Glar; Fock, Martin W.

    2003-01-01

    %) particle separation by the hot secondary cyclone. The next LT-CFB experiment, currently under preparation, is expected to be on either municipal/industrial waste or animal manure. Eventually a 500 kW LT-CFB test plant scheduled for commission during summer 2003, and the anticipated primary LT......The Low Temperature Circulating Fluidised Bed (LT-CFB) gasification process aims at avoiding problems due to ash deposition and agglomeration when using difficult fuels such as agricultural biomass and many waste materials. This, as well as very simple gas cleaning, is achieved by pyrolysing...... the fuel at around 650?C in a CFB reaction chamber and subsequently gasifying the char at around 730oC in a slowly fluidised bubbling bed chamber located in the CFB particle recirculation path. In this paper the novel LT-CFB concept is further described together with the latest test results from the 50 k...

  13. High temperature industrial heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    Berghmans, J. (Louvain Univ., Heverlee (Belgium). Inst. Mechanica)

    1990-01-01

    The present report intends to describe the state of the art of high temperature industrial heat pumps. A description is given of present systems on the market. In addition the research and development efforts on this subject are described. Compression (open as well as closed cycle) systems, as well as absorption heat pumps (including transformers), are considered. This state of the art description is based upon literature studies performed by a team of researchers from the Katholieke Universiteit Leuven, Belgium. The research team also analysed the economics of heat pumps of different types under the present economic conditions. The heat pumps are compared with conventional heating systems. This analysis was performed in order to evaluate the present condition of the heat pump in the European industry.

  14. LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

    Energy Technology Data Exchange (ETDEWEB)

    Harlan U. Anderson

    2000-03-31

    This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and Testing of Planar Single Cells. During this time period substantial progress has been made in developing low temperature deposition techniques to produce dense, nanocrystalline yttrium-stabilized zirconia films on both dense oxide and polymer substrates. Progress has been made in the preparation and characterization of thin electrolytes and porous LSM substrates. Both of these tasks are essentially on or ahead of schedule. In our proposal, we suggested that the ZrO{sub 2}/Sc system needed to be considered as a candidate as a thin electrolyte. This was because microcrystalline ZrO{sub 2}/Sc has a significantly higher ionic conductivity than YSZ, particularly at the lower temperatures. As a result, some 0.5 micron thick film of ZrO{sub 2}/16% Sc on an alumina substrate (grain size 20nm) was prepared and the electrical conductivity measured as a function of temperature and oxygen activity. The Sc doped ZrO{sub 2} certainly has a higher conductivity that either 20nm or 2400nm YSZ, however, electronic conductivity dominates the conductivity for oxygen activities below 10{sup -15}. Whereas for YSZ, electronic conductivity is not a problem until the oxygen activity decreases below 10{sup -25}. These initial results show that the ionic conductivity of 20nm YSZ and 20nm ZrO{sub 2}/16% Sc are essentially the same and the enhanced conductivity which is observed for Sc doping in microcrystalline specimens is not observed for the same composition when it is nanocrystalline. In addition they show that the electronic conductivity of Sc doped ZrO{sub 2} is at least two orders of magnitude higher than that observed for YSZ. The conclusion one reaches is that for 0.5 to 1 micron thick nanocrystalline films, Sc doping of ZrO{sub 2} has no benefits compared to YSZ. As a result, electrolyte films of ZrO{sub 2}/Sc should not be considered as candidates

  15. Low Temperature Hydrogen Antihydrogen Interactions

    International Nuclear Information System (INIS)

    Armour, E. A. G.; Chamberlain, C. W.

    2001-01-01

    In view of current interest in the trapping of antihydrogen (H-bar) atoms at low temperatures, we have carried out a full four-body variational calculation to determine s-wave elastic phase shifts for hydrogen antihydrogen scattering, using the Kohn Variational Principle. Terms outside the Born-Oppenheimer approximation have been taken into account using the formalism of Kolos and Wolniewicz. As far as we are aware, this is the first time that these terms have been included in an H H-bar scattering calculation. This is a continuation of earlier work on H-H-bar interactions. Preliminary results differ substantially from those calculated using the Born-Oppenheimer approximation. A method is outlined for reducing this discrepancy and taking the rearrangement channel into account.

  16. High temperature humidity sensing materials

    International Nuclear Information System (INIS)

    Tsai, P.P.; Tanase, S.; Greenblatt, M.

    1989-01-01

    This paper reports on new proton conducting materials prepared and characterized for potential applications in humidity sensing at temperatures higher than 100 degrees C by complex impedance or galvanic cell type techniques. Calcium metaphosphate, β-Ca(PO 3 ) 2 as a galvanic cell type sensor material yields reproducible signals in the range from 5 to 200 mm Hg water vapor pressure at 578 degrees C, with short response time (∼ 30 sec). Polycrystalline samples of α-Zr(HPO 4 ) 2 and KMo 3 P 5.8 Si 2 O 25 , and the gel converted ceramic, 0.10Li 2 O-0.25P 2 O 5 -0.65SiO 2 as impedance sensor materials show decreases in impedance with increasing humidity in the range from 9 mm Hg to 1 atm water vapor pressure at 179 degrees C

  17. Faraday imaging at high temperatures

    Science.gov (United States)

    Hackel, Lloyd A.; Reichert, Patrick

    1997-01-01

    A Faraday filter rejects background light from self-luminous thermal objects, but transmits laser light at the passband wavelength, thus providing an ultra-narrow optical bandpass filter. The filter preserves images so a camera looking through a Faraday filter at a hot target illuminated by a laser will not see the thermal radiation but will see the laser radiation. Faraday filters are useful for monitoring or inspecting the uranium separator chamber in an atomic vapor laser isotope separation process. Other uses include viewing welds, furnaces, plasma jets, combustion chambers, and other high temperature objects. These filters are can be produced at many discrete wavelengths. A Faraday filter consists of a pair of crossed polarizers on either side of a heated vapor cell mounted inside a solenoid.

  18. Faraday imaging at high temperatures

    International Nuclear Information System (INIS)

    Hackel, L.A.; Reichert, P.

    1997-01-01

    A Faraday filter rejects background light from self-luminous thermal objects, but transmits laser light at the passband wavelength, thus providing an ultra-narrow optical bandpass filter. The filter preserves images so a camera looking through a Faraday filter at a hot target illuminated by a laser will not see the thermal radiation but will see the laser radiation. Faraday filters are useful for monitoring or inspecting the uranium separator chamber in an atomic vapor laser isotope separation process. Other uses include viewing welds, furnaces, plasma jets, combustion chambers, and other high temperature objects. These filters are can be produced at many discrete wavelengths. A Faraday filter consists of a pair of crossed polarizers on either side of a heated vapor cell mounted inside a solenoid. 3 figs

  19. Laser Pyrometer For Spot Temperature Measurements

    Science.gov (United States)

    Elleman, D. D.; Allen, J. L.; Lee, M. C.

    1988-01-01

    Laser pyrometer makes temperature map by scanning measuring spot across target. Scanning laser pyrometer passively measures radiation emitted by scanned spot on target and calibrated by similar passive measurement on blackbody of known temperature. Laser beam turned on for active measurements of reflectances of target spot and reflectance standard. From measurements, temperature of target spot inferred. Pyrometer useful for non-contact measurement of temperature distributions in processing of materials.

  20. Carbon nanotube temperature and pressure sensors

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Ilia N.; Geohegan, David B.

    2017-09-12

    The present invention, in one embodiment, provides a method of measuring pressure or temperature using a sensor including a sensor element composed of a plurality of carbon nanotubes. In one example, the resistance of the plurality of carbon nanotubes is measured in response to the application of temperature or pressure. The changes in resistance are then recorded and correlated to temperature or pressure. In one embodiment, the present invention provides for independent measurement of pressure or temperature using the sensors disclosed herein.

  1. Elevation in brain temperature during paradoxical sleep.

    Science.gov (United States)

    Kawamura, H; Sawyer, C H

    1965-11-12

    During ordinary sleep, the temperature of the rabbit brain tended to drop, but during paradoxical sleep it rose sharply 0.1 degrees to 0.4 degrees C, a greater elevation than was observed during arousal. Changes in body temperature generally did not parallel the alterations in brain temperature. Shifts of direct-current potential in the brain are basically independent of the changes in brain temperature.

  2. Carbon nanotube temperature and pressure sensors

    Science.gov (United States)

    Ivanov, Ilia N; Geohegan, David Bruce

    2013-10-29

    The present invention, in one embodiment, provides a method of measuring pressure or temperature using a sensor including a sensor element composed of a plurality of carbon nanotubes. In one example, the resistance of the plurality of carbon nanotubes is measured in response to the application of temperature or pressure. The changes in resistance are then recorded and correlated to temperature or pressure. In one embodiment, the present invention provides for independent measurement of pressure or temperature using the sensors disclosed herein.

  3. Crowdsourcing urban air temperature measurements using smartphones

    Science.gov (United States)

    Balcerak, Ernie

    2013-10-01

    Crowdsourced data from cell phone battery temperature sensors could be used to contribute to improved real-time, high-resolution air temperature estimates in urban areas, a new study shows. Temperature observations in cities are in some cases currently limited to a few weather stations, but there are millions of smartphone users in many cities. The batteries in cell phones have temperature sensors to avoid damage to the phone.

  4. Extended Temperature Solar Cell Technology Development

    Science.gov (United States)

    Landis, Geoffrey A.; Jenkins, Phillip; Scheiman, David; Rafaelle, Ryne

    2004-01-01

    Future NASA missions will require solar cells to operate both in regimes closer to the sun, and farther from the sun, where the operating temperatures will be higher and lower than standard operational conditions. NASA Glenn is engaged in testing solar cells under extended temperature ranges, developing theoretical models of cell operation as a function of temperature, and in developing technology for improving the performance of solar cells for both high and low temperature operation.

  5. Corrosion Resistant Coatings for High Temperature Applications

    Energy Technology Data Exchange (ETDEWEB)

    Besman, T.M.; Cooley, K.M.; Haynes, J.A.; Lee, W.Y.; Vaubert, V.M.

    1998-12-01

    Efforts to increase efficiency of energy conversion devices have required their operation at ever higher temperatures. This will force the substitution of higher-temperature structural ceramics for lower temperature materials, largely metals. Yet, many of these ceramics will require protection from high temperature corrosion caused by combustion gases, atmospheric contaminants, or the operating medium. This paper discusses examples of the initial development of such coatings and materials for potential application in combustion, aluminum smelting, and other harsh environments.

  6. What is felt temperature? Air conditioning with felt temperature in buildings and vehicles?; Was ist gefuehlte Temperatur? Klimaregelung mit gefuehlter Temperatur in Gebaeuden und Fahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Eigel, Franz [Technology Marketing Support, St. Georgen (Germany); Rengshausen, Detlef [Vereta GmbH, Einbeck (Germany)

    2010-11-15

    The term 'felt temperature' reaches back to a long series of medical, empirical-sociological and meteorological studies accomplished world-wide for human temperature feeling. The consideration of the felt temperature at the regulation of refrigerators meets not only the comfort feeling of humans, but also saves cash money at the same time.

  7. High Temperature Chemistry at NASA: Hot Topics

    Science.gov (United States)

    Jacobson, Nathan S.

    2014-01-01

    High Temperature issues in aircraft engines Hot section: Ni and Co based Superalloys Oxidation and Corrosion (Durability) at high temperatures. Thermal protection system (TPS) and RCC (Reinforced Carbon-Carbon) on the Space Shuttle Orbiter. High temperatures in other worlds: Planets close to their stars.

  8. Low temperature study of nonstoichiometric titanium carbide

    International Nuclear Information System (INIS)

    Tashmetov, M.Yu.

    2005-05-01

    By low temperature neutron diffraction method was studied structure in nonstoichiometric titanium carbide from room temperature up to 12K. It is found of low temperature phase in titanium carbide- TiC 0.71 . It is established region and borders of this phase. It is determined change of unit cell parameter. (author)

  9. Measuring Poisson Ratios at Low Temperatures

    Science.gov (United States)

    Boozon, R. S.; Shepic, J. A.

    1987-01-01

    Simple extensometer ring measures bulges of specimens in compression. New method of measuring Poisson's ratio used on brittle ceramic materials at cryogenic temperatures. Extensometer ring encircles cylindrical specimen. Four strain gauges connected in fully active Wheatstone bridge self-temperature-compensating. Used at temperatures as low as liquid helium.

  10. Low temperature thermophysical properties of lunar soil

    Science.gov (United States)

    Cremers, C. J.

    1973-01-01

    The thermal conductivity and thermal diffusivity of lunar fines samples from the Apollo 11 and Apollo 12 missions, determined at low temperatures as a function of temperature and various densities, are reviewed. It is shown that the thermal conductivity of lunar soil is nearly the same as that of terrestrial basaltic rock under the same temperature and pressure conditions.

  11. Temperature monitoring of gas-cooled reactors

    International Nuclear Information System (INIS)

    Kaiser, G.E.

    1977-01-01

    The present paper deals with questions like : a) Why temperature monitoring in high-temperature reactors at all. b) How are the measuring positions arranged and how are the measurements designed. c) What technique of temperature measurement is applied. (RW) [de

  12. Borehole Stability in High-Temperature Formations

    Science.gov (United States)

    Yan, Chuanliang; Deng, Jingen; Yu, Baohua; Li, Wenliang; Chen, Zijian; Hu, Lianbo; Li, Yang

    2014-11-01

    In oil and gas drilling or geothermal well drilling, the temperature difference between the drilling fluid and formation will lead to an apparent temperature change around the borehole, which will influence the stress state around the borehole and tend to cause borehole instability in high geothermal gradient formations. The thermal effect is usually not considered as a factor in most of the conventional borehole stability models. In this research, in order to solve the borehole instability in high-temperature formations, a calculation model of the temperature field around the borehole during drilling is established. The effects of drilling fluid circulation, drilling fluid density, and mud displacement on the temperature field are analyzed. Besides these effects, the effect of temperature change on the stress around the borehole is analyzed based on thermoelasticity theory. In addition, the relationships between temperature and strength of four types of rocks are respectively established based on experimental results, and thermal expansion coefficients are also tested. On this basis, a borehole stability model is established considering thermal effects and the effect of temperature change on borehole stability is also analyzed. The results show that the fracture pressure and collapse pressure will both increase as the temperature of borehole rises, and vice versa. The fracture pressure is more sensitive to temperature. Temperature has different effects on collapse pressures due to different lithological characters; however, the variation of fracture pressure is unrelated to lithology. The research results can provide a reference for the design of drilling fluid density in high-temperature wells.

  13. Ultrasensitive string-based temperature sensors

    DEFF Research Database (Denmark)

    Larsen, Tom; Schmid, Silvan; Gronberg, L.

    2011-01-01

    Resonant strings are a promising concept for ultra sensitive temperature detection. We present an analytical model for the sensitivity with which we optimize the temperature response of resonant strings by varying geometry and material. The temperature sensitivity of silicon nitride and aluminum ...

  14. Low temperature thermal conductivities of glassy carbons

    International Nuclear Information System (INIS)

    Anderson, A.C.

    1979-01-01

    The thermal conductivity of glassy carbon in the temperature range 0.1 to 100 0 K appears to depend only on the temperature at which the material was pyrolyzed. The thermal conductivity can be related to the microscopic structure of glassy carbon. The reticulated structure is especially useful for thermal isolation at cryogenic temperatures

  15. Genetic aftereffects of increased temperature in Larix

    Science.gov (United States)

    Michael S. Greenwood; Keith W. Hutchinson

    1996-01-01

    We tested the hypothesis that temperature during gametogenesis and embryogenesis can affect progeny genotype and phenotype. Identical crosses were made among cloned parents of Larix spp. inside and outside a greenhouse, where the temperature inside averaged 4?C above the outside temperature. Significant growth differences as a function of crossing...

  16. Post-placement temperature reduction techniques

    DEFF Research Database (Denmark)

    Liu, Wei; Nannarelli, Alberto

    2010-01-01

    With technology scaled to deep submicron era, temperature and temperature gradient have emerged as important design criteria. We propose two post-placement techniques to reduce peak temperature by intelligently allocating whitespace in the hotspots. Both methods are fully compliant with commercial...

  17. Enhanced temperature-independent magnetoresistance below the ...

    Indian Academy of Sciences (India)

    The film exhibits a large nearly temperature-independent magnetoresistance around 99% in the temperature regime below p. The zero field-cooled (ZFC) and field-cooled (FC) magnetization data at 50 Oe shows irreversibility between the ZFC and FC close to the ferromagnetic transition temperature c = 250 K. The ZFC ...

  18. Precision cryogenic temperature data acquisition system

    International Nuclear Information System (INIS)

    Farah, Y.; Sondericker, J.H.

    1985-01-01

    A Multiplexed Temperature Data Acquisition System with an overall precision of +-25 ppM has been designed using state-of-the-art electronics to accurately read temperature between 2.4 K and 600 K from pre-calibrated transducers such as germanium, silicon diode, thermistor or platinum temperature sensors

  19. High temperature incineration. Densification of granules from high temperature incineration

    International Nuclear Information System (INIS)

    Voorde, N. van de; Claes, J.; Taeymans, A.; Hennart, D.; Gijbels, J.; Balleux, W.; Geenen, G.; Vangeel, J.

    1982-01-01

    The incineration system of radioactive waste discussed in this report, is an ''integral'' system, which directly transforms a definite mixture of burnable and unburnable radioactive waste in a final product with a sufficient insolubility to be safely disposed of. At the same time, a significant volume reduction occurs by this treatment. The essential part of the system is a high temperature incinerator. The construction of this oven started in 1974, and while different tests with simulated inactive or very low-level active waste were carried out, the whole system was progressively and continuously extended and adapted, ending finally in an installation with completely remote control, enclosed in an alpha-tight room. In this report, a whole description of the plant and of its auxiliary installations will be given; then the already gained experimental results will be summarized. Finally, the planning for industrial operation will be briefly outlined. An extended test with radioactive waste, which was carried out in March 1981, will be discussed in the appendix

  20. High temperature alloys and ceramic heat exchanger

    International Nuclear Information System (INIS)

    Okamoto, Masaharu

    1984-04-01

    From the standpoint of energy saving, the future operating temperatures of process heat and gas turbine plants will become higher. For this purpose, ceramics is the most promissing candidate material in strength for application to high-temperature heat exchangers. This report deals with a servey of characteristics of several high-temperature metallic materials and ceramics as temperature-resistant materials; including a servey of the state-of-the-art of ceramic heat exchanger technologies developed outside of Japan, and a study of their application to the intermediate heat exchanger of VHTR (a very-high-temperature gas-cooled reactor). (author)

  1. High-temperature peridotites - lithospheric or asthenospheric?

    International Nuclear Information System (INIS)

    Hops, J.J.; Gurney, J.J.

    1990-01-01

    High-temperature peridotites by definition yield equilibration temperatures greater than 1100 degrees C. On the basis of temperature and pressure calculations, these high-temperature peridotites are amongst the deepest samples entrained by kimberlites on route to the surface. Conflicting models proposing either a lithospheric or asthenospheric origin for the high-temperature peridotites have been suggested. A detailed study of these xenoliths from a single locality, the Jagersfontein kimberlite in the Orange Free State, has been completed as a means of resolving this controversy. 10 refs., 2 figs

  2. Temperature Scaling Law for Quantum Annealing Optimizers.

    Science.gov (United States)

    Albash, Tameem; Martin-Mayor, Victor; Hen, Itay

    2017-09-15

    Physical implementations of quantum annealing unavoidably operate at finite temperatures. We point to a fundamental limitation of fixed finite temperature quantum annealers that prevents them from functioning as competitive scalable optimizers and show that to serve as optimizers annealer temperatures must be appropriately scaled down with problem size. We derive a temperature scaling law dictating that temperature must drop at the very least in a logarithmic manner but also possibly as a power law with problem size. We corroborate our results by experiment and simulations and discuss the implications of these to practical annealers.

  3. Precambrian Surface Temperatures and Molecular Phylogeny

    Science.gov (United States)

    Schwartzman, David; Lineweaver, Charles H.

    2004-06-01

    The timing of emergence of major organismal groups is consistent with the climatic temperature being equal to their upper temperature limit of growth (T_{max}), implying a temperature constraint on the evolution of each group, with the climatic temperature inferred from the oxygen isotope record of marine cherts. Support for this constraint comes from the correlation of T_{max} with the rRNA molecular phylogenetic distance from the last common ancestor (LCA) for both thermophilic Archaea and Bacteria. In particular, this correlation for hyperthermophilic Archaea suggests a climatic temperature of about 120°C at the time of the LCA, likely in the Hadean.

  4. High temperature vapors science and technology

    CERN Document Server

    Hastie, John

    2012-01-01

    High Temperature Vapors: Science and Technology focuses on the relationship of the basic science of high-temperature vapors to some areas of discernible practical importance in modern science and technology. The major high-temperature problem areas selected for discussion include chemical vapor transport and deposition; the vapor phase aspects of corrosion, combustion, and energy systems; and extraterrestrial high-temperature species. This book is comprised of seven chapters and begins with an introduction to the nature of the high-temperature vapor state, the scope and literature of high-temp

  5. Micro string resonators as temperature sensors

    DEFF Research Database (Denmark)

    Larsen, T.; Schmid, S.; Boisen, A.

    2013-01-01

    The resonance frequency of strings is highly sensitive to temperature. In this work we have investigated the applicability of micro string resonators as temperature sensors. The resonance frequency of strings is a function of the tensile stress which is coupled to temperature by the thermal...... to the low thermal mass of the strings. A temperature resolution of 2.5×10-4 °C has been achieved with silicon nitride strings. The theoretical limit for the temperature resolution of 8×10-8 °C has not been reached yet and requires further improvement of the sensor....

  6. Temperature distributions in 136 superficial radiothermotherapies

    International Nuclear Information System (INIS)

    Willich, N.; Duve, S.; Pfluger, T.; Bachmeier, K.

    1992-01-01

    Temperature distributions from 136 superficial radiothermotherapies in patients were analysed and three-dimensionally reconstructed. The calculation of mean values and standard deviations of the temperature measuring probes considering water bolus temperature, master probe temperature, site of the probes relatively to different applicator positions and site of the probes in the heated tissues yielded satisfactory temperature distributions for chest wall treatment in contrast to other regions of the body. Radiothermotherapy was statistically not superior to radiotherapy alone with respect to local tumor control. (authors)

  7. CADDIS Volume 2. Sources, Stressors and Responses: Temperature

    Science.gov (United States)

    Introduction to the temperature module, when to list temperature as a candidate cause, ways to measure temperature, simple and detailed conceptual diagrams for temperature, temperature module references and literature reviews.

  8. Temperature of the Gulf Stream

    Science.gov (United States)

    2002-01-01

    The Gulf Stream is one of the strong ocean currents that carries warm water from the sunny tropics to higher latitudes. The current stretches from the Gulf of Mexico up the East Coast of the United States, departs from North America south of the Chesapeake Bay, and heads across the Atlantic to the British Isles. The water within the Gulf Stream moves at the stately pace of 4 miles per hour. Even though the current cools as the water travels thousands of miles, it remains strong enough to moderate the Northern European climate. The image above was derived from the infrared measurements of the Moderate-resolution Imaging Spectroradiometer (MODIS) on a nearly cloud-free day over the east coast of the United States. The coldest waters are shown as purple, with blue, green, yellow, and red representing progressively warmer water. Temperatures range from about 7 to 22 degrees Celsius. The core of the Gulf Stream is very apparent as the warmest water, dark red. It departs from the coast at Cape Hatteras, North Carolina. The cool, shelf water from the north entrains the warmer outflows from the Chesapeake and Delaware Bays. The north wall of the Gulf Stream reveals very complex structure associated with frontal instabilities that lead to exchanges between the Gulf Stream and inshore waters. Several clockwise-rotating warm core eddies are evident north of the core of the Gulf Stream, which enhance the exchange of heat and water between the coastal and deep ocean. Cold core eddies, which rotate counter clockwise, are seen south of the Gulf Stream. The one closest to Cape Hatteras is entraining very warm Gulf Stream waters on its northwest circumference. Near the coast, shallower waters have warmed due to solar heating, while the deeper waters offshore are markedly cooler (dark blue). MODIS made this observation on May 8, 2000, at 11:45 a.m. EDT. For more information, see the MODIS-Ocean web page. The sea surface temperature image was created at the University of Miami using

  9. Temperature impacts on deep-sea biodiversity.

    Science.gov (United States)

    Yasuhara, Moriaki; Danovaro, Roberto

    2016-05-01

    Temperature is considered to be a fundamental factor controlling biodiversity in marine ecosystems, but precisely what role temperature plays in modulating diversity is still not clear. The deep ocean, lacking light and in situ photosynthetic primary production, is an ideal model system to test the effects of temperature changes on biodiversity. Here we synthesize current knowledge on temperature-diversity relationships in the deep sea. Our results from both present and past deep-sea assemblages suggest that, when a wide range of deep-sea bottom-water temperatures is considered, a unimodal relationship exists between temperature and diversity (that may be right skewed). It is possible that temperature is important only when at relatively high and low levels but does not play a major role in the intermediate temperature range. Possible mechanisms explaining the temperature-biodiversity relationship include the physiological-tolerance hypothesis, the metabolic hypothesis, island biogeography theory, or some combination of these. The possible unimodal relationship discussed here may allow us to identify tipping points at which on-going global change and deep-water warming may increase or decrease deep-sea biodiversity. Predicted changes in deep-sea temperatures due to human-induced climate change may have more adverse consequences than expected considering the sensitivity of deep-sea ecosystems to temperature changes. © 2014 Cambridge Philosophical Society.

  10. A new cryostat for precise temperature control

    Science.gov (United States)

    Dong, B.; Zhou, G.; Liu, L. Q.; Zhang, X.; Xiong, L. Y.; Li, Q.

    2013-09-01

    Gifford-McMahon (GM) cryocoolers are often used in cryostat as cold sources. It has advantages of simple structure and low operating cost as well as disadvantages of vibration and temperature oscillation, which are fatal for some applications that are very sensitive to temperature stability at low temperature. To solve the problem, a thermal analysis model which is used to simulate heat transfer in the cryostat is built and discussed. According to the analysis results, a cryostat that can provide variable temperature (4-20 K) for the accurate temperature control experiments is designed and manufactured. In this cryostat, a polytetrafluoroethylene (PTFE) sheet is used as a thermal damper to reduce the temperature oscillation, with which, the temperature oscillation of the sample cooling holder is less than 4 mK at the 20 K region.

  11. Nuclear fuels for very high temperature applications

    International Nuclear Information System (INIS)

    Lundberg, L.B.; Hobbins, R.R.

    1992-01-01

    The success of the development of nuclear thermal propulsion devices and thermionic space nuclear power generation systems depends on the successful utilization of nuclear fuel materials at temperatures in the range 2000 to 3500 K. Problems associated with the utilization of uranium bearing fuel materials at these very high temperatures while maintaining them in the solid state for the required operating times are addressed. The critical issues addressed include evaporation, melting, reactor neutron spectrum, high temperature chemical stability, fabrication, fission induced swelling, fission product release, high temperature creep, thermal shock resistance, and fuel density, both mass and fissile atom. Candidate fuel materials for this temperature range are based on UO 2 or uranium carbides. Evaporation suppression, such as a sealed cladding, is required for either fuel base. Nuclear performance data needed for design are sparse for all candidate fuel forms in this temperature range, especially at the higher temperatures

  12. Temperature and electrical memory of polymer fibers

    International Nuclear Information System (INIS)

    Yuan, Jinkai; Zakri, Cécile; Grillard, Fabienne; Neri, Wilfrid; Poulin, Philippe

    2014-01-01

    We report in this work studies of the shape memory behavior of polymer fibers loaded with carbon nanotubes or graphene flakes. These materials exhibit enhanced shape memory properties with the generation of a giant stress upon shape recovery. In addition, they exhibit a surprising temperature memory with a peak of generated stress at a temperature nearly equal to the temperature of programming. This temperature memory is ascribed to the presence of dynamical heterogeneities and to the intrinsic broadness of the glass transition. We present recent experiments related to observables other than mechanical properties. In particular nanocomposite fibers exhibit variations of electrical conductivity with an accurate memory. Indeed, the rate of conductivity variations during temperature changes reaches a well defined maximum at a temperature equal to the temperature of programming. Such materials are promising for future actuators that couple dimensional changes with sensing electronic functionalities

  13. Temperature dependency in motor skill learning.

    Science.gov (United States)

    Immink, Maarten A; Wright, David L; Barnes, William S

    2012-01-01

    The present study investigated the role of temperature as a contextual condition for motor skill learning. Precision grip task training occurred while forearm cutaneous temperature was either heated (40-45 °C) or cooled (10-15 °C). At test, temperature was either reinstated or changed. Performance was comparable between training conditions while at test, temperature changes decreased accuracy, especially after hot training conditions. After cold training, temperature change deficits were only evident when concurrent force feedback was presented. These findings are the first evidence of localized temperature dependency in motor skill learning in humans. Results are not entirely accounted for by a context-dependent memory explanation and appear to represent an interaction of neuromuscular and sensory processes with the temperature present during training and test.

  14. What Controls the Arctic Lower Stratosphere Temperature?

    Science.gov (United States)

    Newman, Paul A.; Nash, Eric R.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    The temperature of the Arctic lower stratosphere is critical for understanding polar ozone levels. As temperatures drop below about 195 K, polar stratospheric clouds form, which then convert HCl and ClONO2 into reactive forms that are catalysts for ozone loss reactions. Hence, the lower stratospheric temperature during the March period is a key parameter for understanding polar ozone losses. The temperature is basically understood to be a result of planetary waves which drive the polar temperature away from a cold "radiative equilibrium" state. This is demonstrated using NCEP/NCAR reanalysis calculations of the heat flux and the mean polar temperature. The temperature during the March period is fundamentally driven by the integrated impact of large scale waves moving from the troposphere to the stratosphere during the January through February period. We will further show that the recent cold years in the northern polar vortex are a result of this weakened wave driving of the stratosphere.

  15. Temperature monitoring device and thermocouple assembly therefor

    Science.gov (United States)

    Grimm, Noel P.; Bauer, Frank I.; Bengel, Thomas G.; Kothmann, Richard E.; Mavretish, Robert S.; Miller, Phillip E.; Nath, Raymond J.; Salton, Robert B.

    1991-01-01

    A temperature monitoring device for measuring the temperature at a surface of a body, composed of: at least one first thermocouple and a second thermocouple; support members supporting the thermocouples for placing the first thermocouple in contact with the body surface and for maintaining the second thermocouple at a defined spacing from the body surface; and a calculating circuit connected to the thermocouples for receiving individual signals each representative of the temperature reading produced by a respective one of the first and second thermocouples and for producing a corrected temperature signal having a value which represents the temperature of the body surface and is a function of the difference between the temperature reading produced by the first thermocouple and a selected fraction of the temperature reading provided by the second thermocouple.

  16. Theta, time reversal and temperature

    Energy Technology Data Exchange (ETDEWEB)

    Gaiotto, Davide [Perimeter Institute for Theoretical Physics,Waterloo, Ontario, N2L 2Y5 (Canada); Kapustin, Anton [Walter Burke Institute for Theoretical Physics, California Institute of Technology,Pasadena, CA 91125 (United States); Komargodski, Zohar [Department of Particle Physics and Astrophysics, Weizmann Institute of Science,Rehovot 76100 (Israel); Seiberg, Nathan [School of Natural Sciences, Institute for Advanced Study,Princeton, NJ 08540 (United States)

    2017-05-17

    SU(N) gauge theory is time reversal invariant at θ=0 and θ=π. We show that at θ=π there is a discrete ’t Hooft anomaly involving time reversal and the center symmetry. This anomaly leads to constraints on the vacua of the theory. It follows that at θ=π the vacuum cannot be a trivial non-degenerate gapped state. (By contrast, the vacuum at θ=0 is gapped, non-degenerate, and trivial.) Due to the anomaly, the theory admits nontrivial domain walls supporting lower-dimensional theories. Depending on the nature of the vacuum at θ=π, several phase diagrams are possible. Assuming area law for space-like loops, one arrives at an inequality involving the temperatures at which CP and the center symmetry are restored. We also analyze alternative scenarios for SU(2) gauge theory. The underlying symmetry at θ=π is the dihedral group of 8 elements. If deconfined loops are allowed, one can have two O(2)-symmetric fixed points. It may also be that the four-dimensional theory around θ=π is gapless, e.g. a Coulomb phase could match the underlying anomalies.

  17. Low-temperature nuclear orientation

    International Nuclear Information System (INIS)

    Stone, N.J.; Postma, H.

    1986-01-01

    This book comprehensively surveys the many aspects of the low temperature nuclear orientation method. The angular distribution of radioactive emissions from nuclei oriented by hyperfine interactions in solids, is treated experimentally and theoretically. A general introductory chapter is followed by formal development of the theory of the orientation process and the anisotropic emission of decay products from oriented nuclei, applied to radioactive decay and to reactions. Five chapters on applications to nuclear physics cover experimental studies of alpha, beta and gamma emission, nuclear moment measurement and level structure information. Nuclear orientation studies of parity non-conservation and time reversal asymmetry are fully described. Seven chapters cover aspects of hyperfine interactions, magnetic and electric, in metals, alloys and insulating crystals, including ordered systems. Relaxation phenomena and the combined technique of NMR detection using oriented nuclei are treated at length. Chapters on the major recent development of on-line facilities, giving access to short lived nuclei far from stability, on the use of nuclear orientation for thermometry below 1 Kelvin and on technical aspects of the method complete the main text. Extensive appendices, table of relevant parameters and over 1000 references are included to assist the design of future experiments. (Auth.)

  18. Correlation Models for Temperature Fields

    KAUST Repository

    North, Gerald R.

    2011-05-16

    This paper presents derivations of some analytical forms for spatial correlations of evolving random fields governed by a white-noise-driven damped diffusion equation that is the analog of autoregressive order 1 in time and autoregressive order 2 in space. The study considers the two-dimensional plane and the surface of a sphere, both of which have been studied before, but here time is introduced to the problem. Such models have a finite characteristic length (roughly the separation at which the autocorrelation falls to 1/e) and a relaxation time scale. In particular, the characteristic length of a particular temporal Fourier component of the field increases to a finite value as the frequency of the particular component decreases. Some near-analytical formulas are provided for the results. A potential application is to the correlation structure of surface temperature fields and to the estimation of large area averages, depending on how the original datastream is filtered into a distribution of Fourier frequencies (e.g., moving average, low pass, or narrow band). The form of the governing equation is just that of the simple energy balance climate models, which have a long history in climate studies. The physical motivation provided by the derivation from a climate model provides some heuristic appeal to the approach and suggests extensions of the work to nonuniform cases.

  19. Correlation Models for Temperature Fields

    KAUST Repository

    North, Gerald R.; Wang, Jue; Genton, Marc G.

    2011-01-01

    This paper presents derivations of some analytical forms for spatial correlations of evolving random fields governed by a white-noise-driven damped diffusion equation that is the analog of autoregressive order 1 in time and autoregressive order 2 in space. The study considers the two-dimensional plane and the surface of a sphere, both of which have been studied before, but here time is introduced to the problem. Such models have a finite characteristic length (roughly the separation at which the autocorrelation falls to 1/e) and a relaxation time scale. In particular, the characteristic length of a particular temporal Fourier component of the field increases to a finite value as the frequency of the particular component decreases. Some near-analytical formulas are provided for the results. A potential application is to the correlation structure of surface temperature fields and to the estimation of large area averages, depending on how the original datastream is filtered into a distribution of Fourier frequencies (e.g., moving average, low pass, or narrow band). The form of the governing equation is just that of the simple energy balance climate models, which have a long history in climate studies. The physical motivation provided by the derivation from a climate model provides some heuristic appeal to the approach and suggests extensions of the work to nonuniform cases.

  20. High Temperature Superconducting Underground Cable

    International Nuclear Information System (INIS)

    Farrell, Roger A.

    2010-01-01

    The purpose of this Project was to design, build, install and demonstrate the technical feasibility of an underground high temperature superconducting (HTS) power cable installed between two utility substations. In the first phase two HTS cables, 320 m and 30 m in length, were constructed using 1st generation BSCCO wire. The two 34.5 kV, 800 Arms, 48 MVA sections were connected together using a superconducting joint in an underground vault. In the second phase the 30 m BSCCO cable was replaced by one constructed with 2nd generation YBCO wire. 2nd generation wire is needed for commercialization because of inherent cost and performance benefits. Primary objectives of the Project were to build and operate an HTS cable system which demonstrates significant progress towards commercial progress and addresses real world utility concerns such as installation, maintenance, reliability and compatibility with the existing grid. Four key technical areas addressed were the HTS cable and terminations (where the cable connects to the grid), cryogenic refrigeration system, underground cable-to-cable joint (needed for replacement of cable sections) and cost-effective 2nd generation HTS wire. This was the worlds first installation and operation of an HTS cable underground, between two utility substations as well as the first to demonstrate a cable-to-cable joint, remote monitoring system and 2nd generation HTS.