21 research outputs found

    Application of the TDMA Technique Toward the Size and Charge Distribution Measurement of Graphite, Gold, Palladium, and Silver Aerosols

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    The knowledge of charge distributions among aerosol particles has been an important topic for many years because of the strong electrostatic interactions which can greatly influence aerosol transport and evolution. Theoretical models have been developed although experimental verification has been limited because of the difficulty in measuring charged aerosols. Recently a method utilizing a tandem differential mobility analyzer (TDMA) has been shown to be applicable toward measuring both the size and charge distributions of nanosized combustion aerosols. The goal of this work is on further exploration of this method toward the measurement of non-combustion aerosols and in particular those associated with very high temperature reactors (VHTRs). The complete bipolar charge and size distributions of spark generated graphite, gold, silver, and palladium aerosol have been measured with a TDMA apparatus assembled and calibrated during this study. In addition, an electrostatic precipitator has been designed and constructed for measuring the size distributions of neutrally charged particles associated with these aerosols. The results show charge asymmetry in all measured aerosols with higher concentrations of positively charged particles than negative at the same charge level. These results differ from equilibrium charge distributions of both Boltzmann and Fuchs showing that charge equilibrium may not always be an appropriate assumption. The TDMA technique should find applications in characterizing VHTR aerosols and rate processes such as coagulation, deposition, and resuspension which will be important for both reactor design, and accident modeling and simulation

    Colloque. La coexistence confessionnelle en France et dans les mondes germaniques

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    Du 18 au 20 octobre 2012, se tiendra à Strasbourg un colloque international portant sur La coexistence confessionnelle en France et dans les mondes germaniques du Moyen Âge à nos jours. Il est organisé par la Société d’histoire religieuse de la France, l’université de Strasbourg (EA ARCHE) et l’Institut universitaire de France. Programme : Jeudi 18 octobre / Après-midi Présidence de séance : Jean-Marie Husser, université de Strasbourg. 14h00 : Ouverture du colloque. Nicolas Bourguinat, direct..

    Groupe de travail « Philosophie des mathématiques »

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    Responsables : Giuseppina Ronzitti et Tero Tulenheimo 1ère séance : vendredi 28 septembre 2012, 13h-15h Introduction du séminaire de lecture de Pénélope Maddy, Realism in mathematics - Clarendon Press, 1992, par G. Ronzitti. voir le site du groupe de travail. Université Lille 3, Maison de la recherche, salle F1.07
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