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Identification of Thermal Degradation Products from Diuron and IprodioneDiuron and iprodione were pyrolyzed at 400-1000 °C in a helium atmosphere. They showed many similarities in their thermal behavior: both emitted carbon monoxide, hydrogen chloride, and hydrogen cyanide. The N-CO bonds were the first to be split and led to an isocyanate and an amine which degraded in turn into substituted ureas and gaseous products.With the objective of limiting the dangers resulting from chemical products, many industrial countries established regulations which have led to studies of the fate of these products. The behavior of some widely distributed pesticides when subjected to heat have already been described either for the thermal destruction of wastes and stocks (Me

The catalytic activity of several iron additives was studied during the liquefaction of poplar wood suspended in water at 340°C. Iron powder gave good oil yields of -40%. The iron seemed to be an effective additive at the beginning of the reaction before being converted into Fe304. A systematic study of the influence of the initial pressure and volumetric composition of the gas phase (hydrogen-helium mixtures) was also made. An initial pressure in the range 4.0-6.0 MPa was necessary, but the nature of the gas had no significant effect on the yield and the quality of the oils obtained when the percentage amount of iron on dry wood was at least 14%. A stoichiometric equation for the liquefaction reaction is proposed which agrees with experimental results regardless of the initial gas composition.L'activitC catalytique de plusieurs composCs a base de fer a CtC CtudiCe lors de reactions de liquefaction de bois de peuplier, dans I'eau, a 340°C. La poudre de fer conduit ti des rendements en huile d'environ 40%. C'est au dCbut de la rCaction que le fer exercerait son activitC catalytique, et serait ensuite transform6 en Fe304, non actif. Une Ctude systkmatique de l'influence de la pression initiale de gaz et de la nature de ce gaz (melanges hydrogene-hClium) a Cte faite; une pression comprise entre 4,O et 6,O MPa est nkcessaire mais la nature du gaz n'a pas d'influence sur les rendements et la qualitt des huiles obtenues, si le pourcentage de fer par rapport au bois est au moins Cgal a 14%. Une Cquation stoechiomCtrique de la reaction de liquefaction a Ct C Ctablie, elle est valable quelle que soit la nature du gaz initial.wing the energy crisis of the 1970's, people became