... Laboratory and theoretical modelling of the UV bump on the interstellar extinction curve is a very popular topic in dusty investigations. ... feature is illustrated by Fig. 10 where the profiles were calculated using the model of graphite spheres. Figure 10: Normalized extinction efficiencies for graphite spheres. ... The lower panel shows the summary extinction of two graphite spheres with radii and (from upper panel) taken in equal proportions. ...

... We explore the structures immediately surrounding the intermediate-mass young stellar object R Mon with bispec- trum speckle interferometry, conventional near-infrared imaging and by analyzing optical HST archive data. Our near-infrared speckle images with unprecedented diffraction-limited resolution of 55 mas (44 AU; H -band) and 76 mas (61 AU; K -band) represent the highest resolution R Mon images obtained so far and exhibit previously unseen complex structures. ... The features 1­5 are marked. ...