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

  • Total hydrocarbon analysis with a planar micro Flame Ionization detector
    2009 IEEE Sensors, 2009
    Co-Authors: Winfred Kuipers, Jörg Müller
    Abstract:

    This paper discusses the possibility of total hydrocarbon analysis (THA) with a planar micro Flame Ionization detector (μFID). Because of reduced fuel gas consumption, the μFID allows for portable applications, which are numerous in the case of THA. Although, the minimum detectable limit (MDL) and fuel gas consumption are still relatively high compared to commercially available portable devices, these first investigations are promising and it is believed that similar or better performance with respect to MDL, linear range and fuel gas consumption can be achieved. Especially, the novel approach of sampling from atmospheric pressure and simultaneously improving Flame stability by evacuating the Flame chamber is promising.

  • A planar micro-Flame Ionization detector with an integrated guard electrode
    Journal of Micromechanics and Microengineering, 2008
    Co-Authors: Winfred Kuipers, Jörg Müller
    Abstract:

    The Flame Ionization detector (FID) quantifies small concentrations of organic compounds by Flame Ionization of hydrocarbons and measurement of the resulting ion current. The ion current represents the number of carbon atoms in the sample gas. The miniaturization of the FID by MEMS technology (µFID) is expected to increase its use, because of reduced oxyhydrogen consumption. This loosens safety precautions and makes portable applications possible. In contrast to a former µFID design, the current planar µFID is designed to prevent environmental air from entering the system and deteriorating the measurement signal. The oxyhydrogen Flame burns in the silicon plane of an almost completely encapsulating glass–silicon–glass sandwich. Only a small opening remains for removal of the exhaust gas from the system. In between the detector electrodes, a guard electrode is integrated to intercept and by-pass leak currents past the picoammeter, which then only measures the ion current. Due to the design of the guard electrode, small leak currents are still measured by the picoammeter. Yet, these leak currents can be corrected for to obtain the ion current. Measurements of the ion current as a function of the applied voltage and the sample gas flow show expected FID behaviour.

  • Miniaturized Flame Ionization detector for gas chromatography
    Sensors and Actuators B-chemical, 2002
    Co-Authors: Stefan Zimmermann, Peter Krippner, Albrecht Vogel, Jörg Müller
    Abstract:

    Abstract The Technical University Hamburg-Harburg and ABB Corporate Research are currently exploring the potential to apply silicon–glass microsystems as technology platform for creating a miniaturized Flame Ionization detector (FID). This device can be used for the detection of hydrocarbons in gas chromatography. Design and first characterizations of such micro-FIDs have been published elsewhere in Ref. [1] [Sens. Actuators 63B (3) (2000)]. For a deeper understanding of the performance and further optimization potential, the detectors have now been investigated more detailed. The results of those tests show a detection limit of 104 ppb pentane and 441 ppb methane.

  • Micro Flame Ionization detector and micro Flame spectrometer
    Sensors and Actuators B-chemical, 2000
    Co-Authors: Stefan Zimmermann, S. Wischhusen, Jörg Müller
    Abstract:

    Abstract In this paper we present a miniaturized Flame Ionization detector and Flame spectrometer fabricated using conventional micromachining technologies. The main component of both devices is a micro burner unit, which uses minimal oxyhydrogen to produce a stable miniature Flame. The oxyhydrogen is generated at low energy consumption by a miniaturized electrolysis cell, which can be operated by battery. Because of the low oxyhydrogen consumption and the minute scale of the burner unit and electrolyzer the oxyhydrogen is generated as-required, rather than stored as in conventional systems. Thus, there is no explosion hazard and the devices are not only made easily portable, but also safe. Furthermore, these systems possess sensitivity and selectivity that is comparable to conventional systems. Concentrations down to 1 ppm have been demonstrated with the micro Flame Ionization detector and a detection limit in the ppb range appears within reach. The micro Flame spectrometer is undergoing initial development, but measurements based on atomic emission spectrometry demonstrate already a detection limit only 100-fold above levels observed in conventional systems.

Stefan Zimmermann - One of the best experts on this subject based on the ideXlab platform.

  • Miniaturized Flame Ionization detector for gas chromatography
    Sensors and Actuators B-chemical, 2002
    Co-Authors: Stefan Zimmermann, Peter Krippner, Albrecht Vogel, Jörg Müller
    Abstract:

    Abstract The Technical University Hamburg-Harburg and ABB Corporate Research are currently exploring the potential to apply silicon–glass microsystems as technology platform for creating a miniaturized Flame Ionization detector (FID). This device can be used for the detection of hydrocarbons in gas chromatography. Design and first characterizations of such micro-FIDs have been published elsewhere in Ref. [1] [Sens. Actuators 63B (3) (2000)]. For a deeper understanding of the performance and further optimization potential, the detectors have now been investigated more detailed. The results of those tests show a detection limit of 104 ppb pentane and 441 ppb methane.

  • Micro Flame Ionization detector and micro Flame spectrometer
    Sensors and Actuators B-chemical, 2000
    Co-Authors: Stefan Zimmermann, S. Wischhusen, Jörg Müller
    Abstract:

    Abstract In this paper we present a miniaturized Flame Ionization detector and Flame spectrometer fabricated using conventional micromachining technologies. The main component of both devices is a micro burner unit, which uses minimal oxyhydrogen to produce a stable miniature Flame. The oxyhydrogen is generated at low energy consumption by a miniaturized electrolysis cell, which can be operated by battery. Because of the low oxyhydrogen consumption and the minute scale of the burner unit and electrolyzer the oxyhydrogen is generated as-required, rather than stored as in conventional systems. Thus, there is no explosion hazard and the devices are not only made easily portable, but also safe. Furthermore, these systems possess sensitivity and selectivity that is comparable to conventional systems. Concentrations down to 1 ppm have been demonstrated with the micro Flame Ionization detector and a detection limit in the ppb range appears within reach. The micro Flame spectrometer is undergoing initial development, but measurements based on atomic emission spectrometry demonstrate already a detection limit only 100-fold above levels observed in conventional systems.

  • Micromachined Flame Ionization detector and Flame spectrometer
    Micromachined Devices and Components V, 1999
    Co-Authors: Stefan Zimmermann, S. Wischhusen, Joerg Mueller
    Abstract:

    In the course of a progressive miniaturization of complex measuring systems conventional Flame Ionization detectors and Flame spectrometers are no longer competitive with the new generation of mobile analysis systems. This paper presents a micro Flame Ionization detector and Flame spectrometer structured by methods of the microsystem technology. Main component is a micro burner unit with a reduced oxyhydrogen consumption to realize a stable miniature oxyhydrogen Flame. The required oxyhydrogen is generated by electrolysis in a miniaturized electrolysis cell at low energy consumption. Thus the electrolyzer can be battery operated. Due to the reduced amount of explosive oxyhydrogen and the small dimensions of the gas supply micro Flame analyzers have an unlimited mobility without safety restrictions and are easy to handle. Furthermore they have a high sensitivity and selectivity similar to conventional systems. Concentrations down to one ppm are detectable up to now with the micro Flame Ionization detector. The micro Flame spectrometer is in its initial stage. First measurements to demonstrate the further possibilities of such a microsystem are presented.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Albert Lynes - One of the best experts on this subject based on the ideXlab platform.

T. Cotgreave - One of the best experts on this subject based on the ideXlab platform.

Jaroslav Janák - One of the best experts on this subject based on the ideXlab platform.

  • Response of the alkali Flame Ionization detector to halogen compounds
    Journal of Chromatography A, 2001
    Co-Authors: M. Dressler, Jaroslav Janák
    Abstract:

    Abstract The response of the alkali Flame Ionization detector to halogen compounds, as well as the effect of the halogen compound structure on the molar response, have been determined using various alkali metals. An increase in response, as compared with the Flame Ionization detector, occurs with sodium with chloro and bromo compounds and with sodium and potassium in the case of iodo compounds. The molar responses of various monobromo compounds are approximately equal. The response to the chlorobenzenes increases proportionately to the number of chlorine atoms in the molecule.

  • EFFECT OF PRESSURE ON THE PERFORMANCE OF THE Flame Ionization DETECTOR
    Journal of Chromatography A, 2001
    Co-Authors: Petr Boček, Jan Novak, Jaroslav Janák
    Abstract:

    Abstract A study has been made of the performance of a Flame Ionization detector operated under various pressures, at either constant volume flow rates or constant mass flow rates, of the gases fed into the Flame. The Ionization efficiency was highly dependent on pressure; up to 10% changes in Ionization efficiency, depending on the H 2 and N 2 flow rates, resulted from varying the pressure within the range 740–780 mm Hg. For precise quantitative gas chromatographic analysis it is essential that the pressure in the Flame Ionization detector should be stabilized. The effects of pressure on the Ionization efficiency seem to stem from their respective effect on the ion-producing mechanisms.