Identification des composés phénoliques dans les feuilles de Homogyne alpina,Petasites albus,Petasites hybridus et Adenostyles alliariae

Four polyphenolheterosides have been isolated from the leaves of Homogyne alpina, Petasites albus, Petasites hybridus and Adenostyles alliariae by means of thin layer and column chromatography on polyamide. Isoquercitrine (II) has been isolated from Petasites albus, Petasites hybridus and Adenostyles alliariae; Astragaline (III) from Petasites albus and Petasites hybridus; Glucoluteoline (IV) from Adenostyles alliariae and Rutine (I) from Homogyne alpina. Piceine (V) has also been isolated from Homogyne alpina.     

Interference of coherent and incoherent interactions in the Master Equation for open systems

The limits of validity of a well known type of Master Equation for open systems are discussed. Using Zwanzig's projector formalism we derive a “Generalized Master Equation” which describes interference processes between coherent and incoherent interactions. The conditions under which this equation reduces to the known ones is given and discussed for laser systems.     

On the stationary properties of an open system with internal coherent interactions

The asymptotic behaviour of an open system in which coherent and incoherent interactions interfere is discussed. It is shown that a stationary density operator exists which is diagonal with the coherent interaction, and that detailed balance is satisfied. A model-independent form for this density operator is given. A class of systems is identified for which the stationary solution can be constructed explicitly and in which some known models are contained.