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Polychlorinated dibenzofurans (PCDFs) and polychlorinated naphthalenes (PCNs) are known to be emitted from municipal waste incinerators (MWIs) with polychlorinated dibenzo-p-dioxins (PCDDs). Two formation paths for PCDD/ Fs could mainly work, which are condensation of the precursors such as chlorophenols and "de novo" formation from carbon. However the correlation between the chemical structure of carbon and the resulting PCDD/Fs still remains unknown. In this study, the PCDD/Fs formation from polycyclic aromatic hydrocarbons (PAHs) and CuCl was examined at 400 under 10% O 2 . Coronene among the PAHs characteristically gave 1,2,8,9-T4CDF and the derivatives. These isomers clearly indicate that chlorination causes the cleavage of the C-C bonds in a coronene molecule and also that oxygen is easily incorporated from its outside to form 1,2,8,9-T4CDF. The symmetrical preformed structures in the coronene molecule enabled to amplify the de novo formation of the isomer. PCNs are also formed directly from these PAHs. Since there have been few reports on the formation mechanism of PCNs, this study will be a first step to know the whole formation paths. We also define the de novo synthesis as the breakdown reaction of a carbon matrix, since the word has been used without the precise definition.

ABSTRACT. There are a number of published empirical formulae for drift-snow transport as a function of wind velocity. Comparing these formulae at the same wind velocity, however, results in considerable disagreement. It is hypothesized that the disparity arises from snow conditions and the various stages of development of drifting snow.The horizontal distribution of drift flux was measured with snow traps along a transect parallel with the wind, beginning at an up-wind boundary that served as the starting point of drifting snow. Results indicate that drift-snow transport cannot be defined uniquely unless the drifting snow attains equilibrium (i.e. the snow profile is saturated ).Saltation of snow particles is thought to prevail near the snow surface. However, the vertical flux profile of saltating snow h as never been measured. Vertical profiles of drift flux from the snow surface to a height of 30 cm were measured at nine levels, using snow traps composed of nine streamers (compartments) . It appears that the saltation flux prevails up to a height of 7-9 cm above the surface, and the suspension flux gradually takes over as the drifting snow develops. RESUME. Profil vertical et accroissement horizontal pour le transport de la neige par le vent.It existe un grand nombre de formules empiriques publiees pour le transport de la neige en fonction de la vitesse du vent. Cependant, en comparant ces formules pour la m eme vitesse de vent, on trouve de considerables discordances. On ernet l'hypothese que ces differences proviennent de ['etat de la neige et des differents stades de developpement de la congere.La distribution horizon tale du flux de neige a ete mesuree a I'aide de trap pes a neige le long d'un alignement parallele au vent, cornmen<;ant en un point a l'amont considere comme le point d'origine du drift. Les resultats montrent qu'on ne peut definir le transport de la neige souffiee de rnaniere unique a moins que le flux de neige n'ait atteint son point d'equilibre (c'est-a-dire que le profil de neige est satun:).On pense que la saltation des particules de neige est le phenomene qui prevaut pres de la surface de la neige. Cependant, les profils verticaux de la neige en saltation n'ontjamais ete mesures. Des profils verticaux de drift depuis la surface de la neige jusqu'a une hauteur de 30 cm ont ete mesures a neuf niveaux grace a des trappes a neige composees de neuf compartiments. 11 apparait que le flux de saltation predomine jusqu'iJ.une hauteur de 7 a 9 cm au-dessus de la surface et que le flux en suspension prend progressivement le pas quand le transport de neige se developpe.