Fig. 4

Emission current (I) with respect to time (t) for AlGr1.25, AlGr1.5, AlGr1.75 and AlGr2 recorded for the preset value of 1 mA.

Emission current (I) with respect to time (t) for AlGr1.25, AlGr1.5, AlGr1.75 and AlGr2 recorded for the preset value of 1 mA.