Peak tensiometry

Among various cases, the so-called peak tensiometry is worth mentioning [89, 90]. This relaxation process is observed when the interfacial area is changed in a linear way, i.e. A(t)=Ao(H-a t) and Eq.(4.49) simplifies to the following relationship... 

Most appropriate are experiments with constant expansion rate dA/dt = const or constant relative expansion d In A/dt = const. When a constant expansion rate is used the resulting interfacial tension runs through a maximum [16]. Therefore, this experiment was called Peak Tensiometry by the authors. The position of the maximum (peak) depends on the expansion rate. 

---