Figure 5
Oxygen X-ray fluorescence maps on (a), (b), (g), (h) ultralene, (c), (d), (i), (j) paraffin on Si3N4 membranes and (e), (f), (k), (l) paraffin on ultralene. In the first session (a), (c), (e) an area previously exposed to Rad3 and (g), (i), (k) another area to Rad4. After breaking the vacuum, a bigger area which covered the area already exposed in the first session was further exposed to observe the effect of the first session, delivering a final dose corresponding to (b), (d), (f) Rad3* or (h), (j), (l) Rad5*. These last panels present the same O map with two different scales to better highlight the intensity values inside the twice-exposed (central panel) and the single-exposed area (surrounding area). |