A system and method for measuring recirculation of blood in a catheter designed for implantation in a human is described. The inventive method is characterized in that the intended contact zone of at least one of the two work pieces with which the latter adjoins to the other work piece is at least partially subjected to a high-energy radiation to such an extent that the glass transition temperature is reduced in a marginal zone. The ionic liquid and hydrocarbon mixture is maintained in contact under conditions which promote the formation of ionic sulfur-containing derivatives that are soluble in the ionic liquid to be formed, thereby enabling extractive removal and separation of the organosulfur compounds from the feedstock. The first and second legs are maintained at the intermediate spread configuration when the plunger is received in the first cavity. Comparison of the power level feedback signal to a target value may occur to generate an amplifier control signal. The interfacial tension agent reduces the size of liquid crystal droplets formed within the polymer-dispersed liquid crystal optical element during polymerization.