The Experts below are selected from a list of 135 Experts worldwide ranked by ideXlab platform
J. Albaladejo - One of the best experts on this subject based on the ideXlab platform.
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Development of a pulsed uniform supersonic gas expansion system based on an aerodynamic chopper for gas phase reaction kinetic studies at ultra-low temperatures
Review of Scientific Instruments, 2015Co-Authors: E. Jiménez, B. Ballesteros, André Canosa, J. Albaladejo, T. M. Townsend, F. J. Maigler, V. Napal, B. R. RoweAbstract:A detailed description of a new pulsed supersonic uniform gas expansion system is presented together with the experimental validation of the setup by applying the CRESU (French acronym for Cinétique de Réaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow ) technique to the gas-phase reaction of OH radicals with 1-butene at ca. 23 K and 0.63 Millibars of helium (carrier gas). The carrier gas flow, containing negligible mixing ratios of OH-precursor and 1-butene, is expanded from a high pressure reservoir (337 Millibars) to a low pressure region (0.63 Millibars) through a convergent-divergent nozzle (Laval type). The novelty of this experimental setup is that the uniform supersonic flow is pulsed by means of a Teflon-coated aerodynamic chopper provided with two symmetrical apertures. Under these operational conditions, the designed Laval nozzle achieves a temperature of (22.4 ± 1.4) K in the gas jet. The spatial characterization of the temperature and the total gas density within the pulsed uniform supersonic flow has also been performed by both aerodynamical and spectroscopic methods. The gas consumption with this technique is considerably reduced with respect to a continuous CRESU system. The kinetics of the OH+1-butene reaction was investigated by the pulsed laser photolysis/laser induced fluorescence technique. The rotation speed of the disk is temporally synchronized with the exit of the photolysis and the probe lasers. The rate coefficient (k OH) for the reaction under investigation was then obtained and compared with the only available data at this temperature.
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Development of a pulsed uniform supersonic gas expansion system based on an aerodynamic chopper for gas phase reaction kinetic studies at ultra-low temperatures
The Review of scientific instruments, 2015Co-Authors: E. Jiménez, B. Ballesteros, André Canosa, T. M. Townsend, F. J. Maigler, V. Napal, Bertrand Rowe, J. AlbaladejoAbstract:A detailed description of a new pulsed supersonic uniform gas expansion system is presented together with the experimental validation of the setup by applying the CRESU (French acronym for Cinetique de Reaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow ) technique to the gas-phase reaction of OH radicals with 1-butene at ca. 23 K and 0.63 Millibars of helium (carrier gas). The carrier gas flow, containing negligible mixing ratios of OH-precursor and 1-butene, is expanded from a high pressure reservoir (337 Millibars) to a low pressure region (0.63 Millibars) through a convergent-divergent nozzle (Laval type). The novelty of this experimental setup is that the uniform supersonic flow is pulsed by means of a Teflon-coated aerodynamic chopper provided with two symmetrical apertures. Under these operational conditions, the designed Laval nozzle achieves a temperature of (22.4 ± 1.4) K in the gas jet. The spatial characterization of the temperature and the total gas density within the pulsed uniform supersonic flow has also been performed by both aerodynamical and spectroscopic methods. The gas consumption with this technique is considerably reduced with respect to a continuous CRESU system. The kinetics of the OH+1-butene reaction was investigated by the pulsed laser photolysis/laser induced fluorescence technique. The rotation speed of the disk is temporally synchronized with the exit of the photolysis and the probe lasers. The rate coefficient (k OH) for the reaction under investigation was then obtained and compared with the only available data at this temperature.
E. Jiménez - One of the best experts on this subject based on the ideXlab platform.
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Development of a pulsed uniform supersonic gas expansion system based on an aerodynamic chopper for gas phase reaction kinetic studies at ultra-low temperatures
Review of Scientific Instruments, 2015Co-Authors: E. Jiménez, B. Ballesteros, André Canosa, J. Albaladejo, T. M. Townsend, F. J. Maigler, V. Napal, B. R. RoweAbstract:A detailed description of a new pulsed supersonic uniform gas expansion system is presented together with the experimental validation of the setup by applying the CRESU (French acronym for Cinétique de Réaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow ) technique to the gas-phase reaction of OH radicals with 1-butene at ca. 23 K and 0.63 Millibars of helium (carrier gas). The carrier gas flow, containing negligible mixing ratios of OH-precursor and 1-butene, is expanded from a high pressure reservoir (337 Millibars) to a low pressure region (0.63 Millibars) through a convergent-divergent nozzle (Laval type). The novelty of this experimental setup is that the uniform supersonic flow is pulsed by means of a Teflon-coated aerodynamic chopper provided with two symmetrical apertures. Under these operational conditions, the designed Laval nozzle achieves a temperature of (22.4 ± 1.4) K in the gas jet. The spatial characterization of the temperature and the total gas density within the pulsed uniform supersonic flow has also been performed by both aerodynamical and spectroscopic methods. The gas consumption with this technique is considerably reduced with respect to a continuous CRESU system. The kinetics of the OH+1-butene reaction was investigated by the pulsed laser photolysis/laser induced fluorescence technique. The rotation speed of the disk is temporally synchronized with the exit of the photolysis and the probe lasers. The rate coefficient (k OH) for the reaction under investigation was then obtained and compared with the only available data at this temperature.
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Development of a pulsed uniform supersonic gas expansion system based on an aerodynamic chopper for gas phase reaction kinetic studies at ultra-low temperatures
The Review of scientific instruments, 2015Co-Authors: E. Jiménez, B. Ballesteros, André Canosa, T. M. Townsend, F. J. Maigler, V. Napal, Bertrand Rowe, J. AlbaladejoAbstract:A detailed description of a new pulsed supersonic uniform gas expansion system is presented together with the experimental validation of the setup by applying the CRESU (French acronym for Cinetique de Reaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow ) technique to the gas-phase reaction of OH radicals with 1-butene at ca. 23 K and 0.63 Millibars of helium (carrier gas). The carrier gas flow, containing negligible mixing ratios of OH-precursor and 1-butene, is expanded from a high pressure reservoir (337 Millibars) to a low pressure region (0.63 Millibars) through a convergent-divergent nozzle (Laval type). The novelty of this experimental setup is that the uniform supersonic flow is pulsed by means of a Teflon-coated aerodynamic chopper provided with two symmetrical apertures. Under these operational conditions, the designed Laval nozzle achieves a temperature of (22.4 ± 1.4) K in the gas jet. The spatial characterization of the temperature and the total gas density within the pulsed uniform supersonic flow has also been performed by both aerodynamical and spectroscopic methods. The gas consumption with this technique is considerably reduced with respect to a continuous CRESU system. The kinetics of the OH+1-butene reaction was investigated by the pulsed laser photolysis/laser induced fluorescence technique. The rotation speed of the disk is temporally synchronized with the exit of the photolysis and the probe lasers. The rate coefficient (k OH) for the reaction under investigation was then obtained and compared with the only available data at this temperature.
Gregory A. Zielinski - One of the best experts on this subject based on the ideXlab platform.
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A classification scheme for winter storms in the eastern and central United States with an emphasis on nor'easters
Bulletin of the American Meteorological Society, 2002Co-Authors: Gregory A. ZielinskiAbstract:Abstract A classification scheme for nor'easters and other winter storms (November-April) in the eastern and central United States provides real-time information on the potential impact of these storms. This scheme also may be applied to winterstorms over the last century to provide a time series of trends and cycles in specific magnitude nor'easters along the East Coast and Colorado lows that migrate northward toward the Great Lakes (i.e., Witches of November). The classification scheme follows a 1-5 hierarchy with category 1 storms being the least severe and category 5storms the most severe. Winter storm/nor'easter category is determined through the development of an intensity index (I) from surface synoptic charts. The 1-5 scale classification scheme of the storm's intensity is determined from the sumof central low pressure difference from 1013 mb, the deepening rate (Millibars per 12 hours) and the maximum pressure gradient in Millibars per 1000 kilometers. A fivescale (1-5) duration factor (DF), inve...
Jan Aarts - One of the best experts on this subject based on the ideXlab platform.
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APPLIED PHYSICS LETTERS - The surface structure of SrTiO3 at high temperatures under influence of oxygen
Applied Physics Letters, 2014Co-Authors: M. B. S. Hesselberth, S. J. Van Der Molen, Jan AartsAbstract:We use low energy electron microscopy to investigate the structure of the SrTiO3 (001) surface at elevated temperatures and different oxygen pressures. Upon varying the temperature between 500 °C and 900 °C in oxygen pressures ranging from 10−9 Millibar to 10−4 Millibar, two surface transitions are found to be present. The lower temperature (1 × 1) → (2 × 1) transition that is known to occur in ultrahigh vacuum can be reversed by increasing the oxygen pressure. At higher temperatures, we observe a (2 × 1) → disordered (1 × 1) transition which is irreversible in the experimental parameter range. The observations are expected to have a strong bearing on the growth of interface structures.
B. R. Rowe - One of the best experts on this subject based on the ideXlab platform.
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Development of a pulsed uniform supersonic gas expansion system based on an aerodynamic chopper for gas phase reaction kinetic studies at ultra-low temperatures
Review of Scientific Instruments, 2015Co-Authors: E. Jiménez, B. Ballesteros, André Canosa, J. Albaladejo, T. M. Townsend, F. J. Maigler, V. Napal, B. R. RoweAbstract:A detailed description of a new pulsed supersonic uniform gas expansion system is presented together with the experimental validation of the setup by applying the CRESU (French acronym for Cinétique de Réaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow ) technique to the gas-phase reaction of OH radicals with 1-butene at ca. 23 K and 0.63 Millibars of helium (carrier gas). The carrier gas flow, containing negligible mixing ratios of OH-precursor and 1-butene, is expanded from a high pressure reservoir (337 Millibars) to a low pressure region (0.63 Millibars) through a convergent-divergent nozzle (Laval type). The novelty of this experimental setup is that the uniform supersonic flow is pulsed by means of a Teflon-coated aerodynamic chopper provided with two symmetrical apertures. Under these operational conditions, the designed Laval nozzle achieves a temperature of (22.4 ± 1.4) K in the gas jet. The spatial characterization of the temperature and the total gas density within the pulsed uniform supersonic flow has also been performed by both aerodynamical and spectroscopic methods. The gas consumption with this technique is considerably reduced with respect to a continuous CRESU system. The kinetics of the OH+1-butene reaction was investigated by the pulsed laser photolysis/laser induced fluorescence technique. The rotation speed of the disk is temporally synchronized with the exit of the photolysis and the probe lasers. The rate coefficient (k OH) for the reaction under investigation was then obtained and compared with the only available data at this temperature.