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  1. Article ; Online: Implementation of ultrasonic sensing for high resolution measurement of binary gas mixture fractions.

    Bates, Richard / Battistin, Michele / Berry, Stephane / Bitadze, Alexander / Bonneau, Pierre / Bousson, Nicolas / Boyd, George / Bozza, Gennaro / Crespo-Lopez, Olivier / Da Riva, Enrico / Degeorge, Cyril / Deterre, Cecile / DiGirolamo, Beniamino / Doubek, Martin / Favre, Gilles / Godlewski, Jan / Hallewell, Gregory / Hasib, Ahmed / Katunin, Sergey /
    Langevin, Nicolas / Lombard, Didier / Mathieu, Michel / McMahon, Stephen / Nagai, Koichi / Pearson, Benjamin / Robinson, David / Rossi, Cecilia / Rozanov, Alexandre / Strauss, Michael / Vitek, Michal / Vacek, Vaclav / Zwalinski, Lukasz

    Sensors (Basel, Switzerland)

    2014  Volume 14, Issue 6, Page(s) 11260–11276

    Abstract: We describe an ultrasonic instrument for continuous real-time analysis of the fractional mixture of a binary gas system. The instrument is particularly well suited to measurement of leaks of a high molecular weight gas into a system that is nominally ... ...

    Abstract We describe an ultrasonic instrument for continuous real-time analysis of the fractional mixture of a binary gas system. The instrument is particularly well suited to measurement of leaks of a high molecular weight gas into a system that is nominally composed of a single gas. Sensitivity < 5 × 10(-5) is demonstrated to leaks of octaflouropropane (C3F8) coolant into nitrogen during a long duration (18 month) continuous study. The sensitivity of the described measurement system is shown to depend on the difference in molecular masses of the two gases in the mixture. The impact of temperature and pressure variances on the accuracy of the measurement is analysed. Practical considerations for the implementation and deployment of long term, in situ ultrasonic leak detection systems are also described. Although development of the described systems was motivated by the requirements of an evaporative fluorocarbon cooling system, the instrument is applicable to the detection of leaks of many other gases and to processes requiring continuous knowledge of particular binary gas mixture fractions.
    MeSH term(s) Chemistry Techniques, Analytical/instrumentation ; Chemistry Techniques, Analytical/methods ; Complex Mixtures/analysis ; Equipment Design ; Equipment Failure Analysis ; Gases/analysis ; Microchemistry/instrumentation ; Microchemistry/methods ; Ultrasonography/instrumentation ; Ultrasonography/methods
    Chemical Substances Complex Mixtures ; Gases
    Language English
    Publishing date 2014-06-24
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2052857-7
    ISSN 1424-8220 ; 1424-8220
    ISSN (online) 1424-8220
    ISSN 1424-8220
    DOI 10.3390/s140611260
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Search for solar axions by the CERN axion solar telescope with 3He buffer gas: closing the hot dark matter gap.

    Arik, M / Aune, S / Barth, K / Belov, A / Borghi, S / Bräuninger, H / Cantatore, G / Carmona, J M / Cetin, S A / Collar, J I / Da Riva, E / Dafni, T / Davenport, M / Eleftheriadis, C / Elias, N / Fanourakis, G / Ferrer-Ribas, E / Friedrich, P / Galán, J /
    García, J A / Gardikiotis, A / Garza, J G / Gazis, E N / Geralis, T / Georgiopoulou, E / Giomataris, I / Gninenko, S / Gómez, H / Gómez Marzoa, M / Gruber, E / Guthörl, T / Hartmann, R / Hauf, S / Haug, F / Hasinoff, M D / Hoffmann, D H H / Iguaz, F J / Irastorza, I G / Jacoby, J / Jakovčić, K / Karuza, M / Königsmann, K / Kotthaus, R / Krčmar, M / Kuster, M / Lakić, B / Lang, P M / Laurent, J M / Liolios, A / Ljubičić, A / Luzón, G / Neff, S / Niinikoski, T / Nordt, A / Papaevangelou, T / Pivovaroff, M J / Raffelt, G / Riege, H / Rodríguez, A / Rosu, M / Ruz, J / Savvidis, I / Shilon, I / Silva, P S / Solanki, S K / Stewart, L / Tomás, A / Tsagri, M / van Bibber, K / Vafeiadis, T / Villar, J / Vogel, J K / Yildiz, S C / Zioutas, K

    Physical review letters

    2014  Volume 112, Issue 9, Page(s) 91302

    Abstract: The CERN Axion Solar Telescope has finished its search for solar axions with (3)He buffer gas, covering the search range 0.64 eV ≲ ma ≲ 1.17 eV. This closes the gap to the cosmological hot dark matter limit and actually overlaps with it. From the absence ...

    Abstract The CERN Axion Solar Telescope has finished its search for solar axions with (3)He buffer gas, covering the search range 0.64 eV ≲ ma ≲ 1.17 eV. This closes the gap to the cosmological hot dark matter limit and actually overlaps with it. From the absence of excess x rays when the magnet was pointing to the Sun we set a typical upper limit on the axion-photon coupling of gaγ ≲ 3.3 × 10(-10)  GeV(-1) at 95% C.L., with the exact value depending on the pressure setting. Future direct solar axion searches will focus on increasing the sensitivity to smaller values of gaγ, for example by the currently discussed next generation helioscope International AXion Observatory.
    Language English
    Publishing date 2014-03-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.112.091302
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Book ; Online: Development of a custom on-line ultrasonic vapour analyzer/flowmeter for the ATLAS inner detector, with application to gaseous tracking and Cherenkov detectors

    Bates, R. / Battistin, M. / Berry, S. / Berthoud, J. / Bitadze, A. / Bonneau, P. / Botelho-Direito, J. / Bousson, N. / Boyd, G. / Bozza, G. / Da Riva, E. / Degeorge, C. / DiGirolamo, B. / Doubek, M. / Godlewski, J. / Hallewell, G. / Katunin, S. / Lombard, D. / Mathieu, M. /
    McMahon, S. / Nagai, K. / Perez-Rodriguez, E. / Rossi, C. / Rozanov, A. / Vacek, V. / Vitek, M. / Zwalinski, L.

    2012  

    Abstract: Precision sound velocity measurements can simultaneously determine binary gas composition and flow. We have developed an analyzer with custom electronics, currently in use in the ATLAS inner detector, with numerous potential applications. The instrument ... ...

    Abstract Precision sound velocity measurements can simultaneously determine binary gas composition and flow. We have developed an analyzer with custom electronics, currently in use in the ATLAS inner detector, with numerous potential applications. The instrument has demonstrated ~0.3% mixture precision for C3F8/C2F6 mixtures and < 10-4 resolution for N2/C3F8 mixtures. Moderate and high flow versions of the instrument have demonstrated flow resolutions of +/- 2% F.S. for flows up to 250 l.min-1, and +/- 1.9% F.S. for linear flow velocities up to 15 ms-1; the latter flow approaching that expected in the vapour return of the thermosiphon fluorocarbon coolant recirculator being built for the ATLAS silicon tracker.

    Comment: Paper submitted to TWEPP2012; Topical Workshop on Electronics for Particle Physics, Oxford, UK, September 17-21, 2012. KEYWORDS: Sonar; Saturated fluorocarbons; Flowmetry; Sound velocity, Gas mixture analysis. 8 pages, 7 figures
    Keywords Physics - Instrumentation and Detectors ; High Energy Physics - Experiment
    Subject code 621
    Publishing date 2012-10-30
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Book ; Online: A combined ultrasonic flow meter and binary vapour mixture analyzer for the ATLAS silicon tracker

    Bates, R. / Battistin, M. / Berry, S. / Berthoud, J. / Bitadze, A. / Bonneau, P. / Botelho-Direito, J. / Bousson, N. / Boyd, G. / Bozza, G. / Da Riva, E. / Degeorge, C. / DiGirolamo, B. / Doubek, M. / Giugni, D. / Godlewski, J. / Hallewell, G. / Katunin, S. / Lombard, D. /
    Mathieu, M. / McMahon, S. / Nagai, K. / Perez-Rodriguez, E. / Rossi, C. / Rozanov, A. / Vacek, V. / Vitek, M. / Zwalinski, L.

    2012  

    Abstract: An upgrade to the ATLAS silicon tracker cooling control system may require a change from C3F8 (octafluoro-propane) evaporative coolant to a blend containing 10-25% of C2F6 (hexafluoro-ethane). Such a change will reduce the evaporation temperature to ... ...

    Abstract An upgrade to the ATLAS silicon tracker cooling control system may require a change from C3F8 (octafluoro-propane) evaporative coolant to a blend containing 10-25% of C2F6 (hexafluoro-ethane). Such a change will reduce the evaporation temperature to assure thermal stability following radiation damage accumulated at full LHC luminosity. Central to this upgrade is a new ultrasonic instrument in which sound transit times are continuously measured in opposite directions in flowing gas at known temperature and pressure to deduce the C3F8/C2F6 flow rate and mixture composition. The instrument and its Supervisory, Control and Data Acquisition (SCADA) software are described in this paper. Several geometries for the instrument are in use or under evaluation. An instrument with a pinched axial geometry intended for analysis and measurement of moderate flow rates has demonstrated a mixture resolution of 3.10-3 for C3F8/C2F6 molar mixtures with 20F6, and a flow resolution of 2% of full scale for mass flows up to 30gs-1. In mixtures of widely-differing molecular weight (mw), higher mixture precision is possible: a sensitivity of <5.10-5 to leaks of C3F8 into part of the ATLAS tracker nitrogen envelope (mw difference 160) has been seen. An instrument with an angled sound path geometry has been developed for use at high fluorocarbon mass flow rates of around 1.2 kgs-1 - corresponding to full flow in a new 60kW thermosiphon recirculator under construction for the ATLAS silicon tracker. Extensive computational fluid dynamics studies were performed to determine the preferred geometry (ultrasonic transducer spacing and placement, together with the sound crossing angle with respect to the vapour flow direction). A prototype with 45deg crossing angle has demonstrated a flow resolution of 1.9% of full scale for linear flow velocities up to 15 ms-1. The instrument has many potential applications.

    Comment: 30 pages, 24 figures, 3 tables KEYWORDS: Sonar; Saturated fluorocarbons; Flowmetry; Sound velocity, Gas mixture analysis
    Keywords Physics - Instrumentation and Detectors ; High Energy Physics - Experiment
    Subject code 621
    Publishing date 2012-10-17
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

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