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Georges Zissis - One of the best experts on this subject based on the ideXlab platform.

  • Frequency dimmable electronic ballast for a 250W HPS Lamp
    2016 7th International Renewable Energy Congress (IREC), 2016
    Co-Authors: Mn Nehdi, W Nsibi, A. Chammam, Anis Sellami, Georges Zissis
    Abstract:

    In this paper, a simple circuit is proposed to achieve ability in dimming range, and to reduce the number of electronic components in the drive circuit, which helps to reduce its cost. Detailed analysis and design of a dimmable electronic-ballast high intensity Discharge Lamp circuit with frequency control are presented. A dimming technique for resonant circuit electronic ballast based on a variable frequency is introduced. Dimming is successfully accomplished and simulation results and experimental results are presented on high-frequency control electronic ballast.

  • Experimental and theoretical investigations on the warm-up of a high-pressure mercury Discharge Lamp
    Physics of Plasmas, 2011
    Co-Authors: J. Zalach, K. Charrada, Z. Araoud, St. Franke, H. Schoepp, Georges Zissis
    Abstract:

    Modern high-pressure Discharge Lamps are forced to provide instant light and hot relight capabilities—if possible at lower power units. A detailed understanding of the warm-up of high-pressure Discharge Lamps is therefore required. Complex fluid model codes were developed for the past years including more and more processes like two-dimensional treatment of convection trying to provide a more comprehensive and consistent description of high-pressure Discharge Lamps. However, there is a lack of experimental data to examine the performance of these models. This work provides a very complete set of geometrical, electrical, spectroscopic, and thermographic data according to the warm-up of a high-pressure mercury Discharge Lamp that is compared to the results of a state of the art fluid code. Quantitative agreement is achieved for single parameters like wall temperatures. But the paper also reveals the need for further investigations and improvements of the code.

  • A Discharge Lamp Model Based on Lamp Dynamic Conductance
    IEEE Transactions on Power Electronics, 2007
    Co-Authors: Cecilio Blanco, J.c. Anton, A. Robles, Francisco Ferrero, Juan Carlos Campo, Manuela Gonzalez, Georges Zissis
    Abstract:

    A model for Discharge Lamp based on Lamp electrical conductance is proposed. Physical assumptions are used to obtain this model. The model allows simulating Lamp behavior at different frequencies and delivered power levels. The model has been verified using a high pressure sodium Lamp supplied at 50 and 100kHz

  • implementation of an efficiency indicator in an electrical modeling of a dielectric barrier Discharge Lamp
    IEEE Industry Applications Society Annual Meeting, 2006
    Co-Authors: S Bhosle, Georges Zissis, J J Damelincourt, A Capdevila, K Gupta, F P Dawson, V F Tarasenko
    Abstract:

    Dielectric barrier Discharge (DBD) excimer or exciplex Lamps are known as efficient UV and VUV sources but their power supply operates at a high voltage (some kV) and at a frequency of some tens of kHz. Consequently, for industrial applications, DBD Lamps need specific power supplies, designed for one Lamp geometry and gas filling. We have proposed in [Bhosle, S et al., 2004] and [Bhosle, S et al., 2005] an electrical model of a DBD which can be implemented in an electrical simulation software and can thus be used as virtual load for innovative DBD power supply design. The aim of that paper is to describe the mechanisms involved in the development of an homogeneous DBD and their transcription to an electrical equivalent circuit where the UV flux of the Discharge can be estimated

  • Numerical modelling of metal halide Discharge Lamp
    Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344), 1
    Co-Authors: L. Troudi, Georges Zissis, S. Aissi, K. Charrada, Mohamed Sassi
    Abstract:

    A finite-element analysis code based on the resolution of fluid equations is developed to simulate metal halide Discharge Lamps. For a realistic modelling of the Discharge, many fundamental data are needed, this work is devoted to the computation of the transport coefficients in Discharge Lamp using thallium iodide doped mercury. For this purpose we have first calculated the plasma composition under local thermodynamic equilibrium (LTE) condition, then we have computed transport coefficients for different interactions. In the next step chemical model will be coupled to a fluid model to simulate the behaviour of the Discharge plasma.

Vladimir Cirkva - One of the best experts on this subject based on the ideXlab platform.

  • microwave photocatalysis of mono chloroacetic acid over nanoporous titanium iv oxide thin films using mercury electrodeless Discharge Lamps
    Journal of Photochemistry and Photobiology A-chemistry, 2008
    Co-Authors: Vladimir Cirkva, Hana žabova, Milan Hajek
    Abstract:

    The degradation of mono-chloroacetic acid (MCAA) by microwave-assisted photocatalysis has been examined by a new method. A novel electrodeless Discharge Lamp (EDL) was employed as UV light source generated by microwave irradiation. Titanium(IV) oxide film was used as the photocatalyst due to its superior characteristics. Several factors influencing the degradation of MCAA, such as number of coating cycles, light intensity, initial pH value, gas bubbling, and H2O2 dosage have been studied in detail. Mono-chloroacetic acid was efficiently decomposed to HCl, CO2, and H2O by the UV irradiated titanium dioxide thin film in a microwave field. The decomposition was enhanced in an alkaline solution and in the presence of H2O2, and significantly enhanced by increasing the intensity of UV light. © 2008 Elsevier B.V. All rights reserved.

  • The electrodeless Discharge Lamp: a prospective tool for photochemistry Part 5: Fill material-dependent emission characteristics
    Journal of Photochemistry and Photobiology A: Chemistry, 2005
    Co-Authors: Pavel Müller, Petr Klán, Vladimir Cirkva
    Abstract:

    This work expands our previous research on an original photochemical reactor consisting of the electrodeless Discharge Lamp (EDL) inside a reaction mixture that generates ultraviolet radiation in the microwave (MW) field. The effects of temperature MW output power of the reactor, and EDL envelope material, were already published [P. M¨uller, P. Klan, V. Cirkva, J. Photochem. Photobiol. A: Chem. 158 (2003) 1]. Now we report on the emission characteristics (250–650 nm) of various EDLs containing different fill materials (Hg, HgI2, Cd, I2, KI, P, Se, and S). While distinct line emission peaks were found for mercury, cadmium and phosphorus fills, iodine, selenium and sulfur-containing EDLs emitted continuous bands. Sulfur-containing EDLs are proposed for phototransformations that are of environmental interest due to the emission flux comparable to solar terrestrial radiation. It is concluded that the right choice of EDL envelope fill material can be very useful in planning an efficient course of photochemical process without necessity of filtering off the undesirable part of the UV radiation by other tools, such as glass or solution filters or monochromators. Quantum efficiency measurements of the Norrish type II reaction were accomplished to compare usefulness of the EDLs in photochemical applications. Sulfur and phosphorus-containing EDLs were found as the most efficient sources of UV radiation.

Martin R. Green - One of the best experts on this subject based on the ideXlab platform.

  • Extreme ultraviolet radiation: A mans of Ion activation for tandem mass spectrometry
    Analytical Chemistry, 2018
    Co-Authors: Alexandre Giuliani, Jonathan P. Williams, Martin R. Green
    Abstract:

    Tandem mass spectrometry has long been established as a corner stone of analytical and structural chemistry. Fast radical-directed dissociation, produced by electron-transfer and electron-capture dissociation (ETD and ECD) has been shown to provide important complementary information to collision-induced dissociation (CID). We report the first application of extreme-ultraviolet (XUV) Lamps to tandem mass spectrometry. These Discharge Lamps are versatile, robust, and low-cost sources of energetic photons (40-80 nm). The coupling of the Discharge Lamp with a Waters Synapt G2-Si Q-ToF mass spectrometer is achieved through a specific trapping scheme in the TriWave region of the instrument, allowing efficient irradiation of the precursor ions. Rich radical-directed dissociation was produced for a number of model compounds, providing unique, complementary information to existing dissociation techniques.

Alexandre Giuliani - One of the best experts on this subject based on the ideXlab platform.

  • Extreme ultraviolet radiation: A mans of Ion activation for tandem mass spectrometry
    Analytical Chemistry, 2018
    Co-Authors: Alexandre Giuliani, Jonathan P. Williams, Martin R. Green
    Abstract:

    Tandem mass spectrometry has long been established as a corner stone of analytical and structural chemistry. Fast radical-directed dissociation, produced by electron-transfer and electron-capture dissociation (ETD and ECD) has been shown to provide important complementary information to collision-induced dissociation (CID). We report the first application of extreme-ultraviolet (XUV) Lamps to tandem mass spectrometry. These Discharge Lamps are versatile, robust, and low-cost sources of energetic photons (40-80 nm). The coupling of the Discharge Lamp with a Waters Synapt G2-Si Q-ToF mass spectrometer is achieved through a specific trapping scheme in the TriWave region of the instrument, allowing efficient irradiation of the precursor ions. Rich radical-directed dissociation was produced for a number of model compounds, providing unique, complementary information to existing dissociation techniques.

  • Atmospheric pressure photoionization mass spectrometry of guanine using tunable synchrotron VUV radiation
    International Journal of Mass Spectrometry, 2012
    Co-Authors: Julie Allegrand, Alexandre Giuliani, David Touboul, Alain Brunelle, Olivier Laprévote
    Abstract:

    Atmospheric pressure photoionization (APPI) source coupled to a krypton Discharge Lamp permits to specifically generate either radical cation or protonated species for guanine depending on the dopant molecule. In order to scrutinize the consecutive or competitive chemical reactions occurring in the gas phase, a tunable synchrotron VUV radiation source was coupled for the first time to the APPI source of a hybrid quadrupole time-of-flight mass spectrometer. Experiments were achieved at different photon energies close to the ionization energy of the different reagents. This unique set-up allowed the confirmation of theoretical models developed by several groups over the last ten years concerning ionization processes underlying APPI, such as proton or charge transfer reactions. (C) 2012 Elsevier B.V. All rights reserved.

  • Tandem mass spectrometer and tandem mass spectrometry method
    2011
    Co-Authors: Alexandre Giuliani, Matthieu Refregiers, Aleksandar R. Milosavljevic, Laurent Nahon
    Abstract:

    The spectrometer has a mass analyzer comprising an ions trap (2) to receive ions from an ionization source (1) and a detecting unit to detect ions leaving the trap based on relative load mass of ions. An ions activation unit activates a part of the trapped ions. A luminescent gas-Discharge Lamp (4) of the activation unit generates a light beam directed toward the trap to fragment energies of photons ranging between 8-41 eV or for photoionization or photodetachment of the electrons guided to the trapped ions, where the beam is electromagnetic radiation in a field of vacuum UV. The luminescent gas-Discharge Lamp is designed as a helium Discharge Lamp, a neon Discharge Lamp, an argon Discharge Lamp or a krypton Discharge Lamp. An independent claim is also included for a tandem mass spectrometry method.

Pavel Müller - One of the best experts on this subject based on the ideXlab platform.

  • The electrodeless Discharge Lamp: a prospective tool for photochemistry Part 5: Fill material-dependent emission characteristics
    Journal of Photochemistry and Photobiology A: Chemistry, 2005
    Co-Authors: Pavel Müller, Petr Klán, Vladimir Cirkva
    Abstract:

    This work expands our previous research on an original photochemical reactor consisting of the electrodeless Discharge Lamp (EDL) inside a reaction mixture that generates ultraviolet radiation in the microwave (MW) field. The effects of temperature MW output power of the reactor, and EDL envelope material, were already published [P. M¨uller, P. Klan, V. Cirkva, J. Photochem. Photobiol. A: Chem. 158 (2003) 1]. Now we report on the emission characteristics (250–650 nm) of various EDLs containing different fill materials (Hg, HgI2, Cd, I2, KI, P, Se, and S). While distinct line emission peaks were found for mercury, cadmium and phosphorus fills, iodine, selenium and sulfur-containing EDLs emitted continuous bands. Sulfur-containing EDLs are proposed for phototransformations that are of environmental interest due to the emission flux comparable to solar terrestrial radiation. It is concluded that the right choice of EDL envelope fill material can be very useful in planning an efficient course of photochemical process without necessity of filtering off the undesirable part of the UV radiation by other tools, such as glass or solution filters or monochromators. Quantum efficiency measurements of the Norrish type II reaction were accomplished to compare usefulness of the EDLs in photochemical applications. Sulfur and phosphorus-containing EDLs were found as the most efficient sources of UV radiation.

  • The electrodeless Discharge Lamp: a prospective tool for photochemistry: Part 4. Temperature- and envelope material-dependent emission characteristics
    Journal of Photochemistry and Photobiology A: Chemistry, 2003
    Co-Authors: Pavel Müller, Petr Klán, Vladimı́r Cı́rkva
    Abstract:

    This work extends our previous research on an original photochemical reactor—the electrodeless Discharge Lamp (EDL) inside a reaction mixture that generates ultraviolet radiation in the microwave (MW) field. This arrangement was found to be a straightforward solution for homogeneous as well as heterogeneous photochemical experiments that need to be carried out at higher temperatures. Here, we report the emission characteristics (250–600 nm) of EDL as a function of temperature, MW output power of the reactor, EDL envelope material, and properties of solvents used in photochemical reactions. Relative intensities of the individual emission peaks were found to be largely dependent on temperature (in the region of 35–174 °C): the short-wavelength bands (particularly the 254 nm peak) were suppressed with increasing temperature. Solvents absorbing MW significantly reduced the EDL emission intensity. It is concluded that the right choice of EDL envelope material and reaction conditions is essential for an efficient course of a photochemical process in this experimental arrangement.