The research presented in this dissertation is a result of several chemical substitution studies on correlated electron systems. Through careful synthesis and measurement at low temperatures, we create lanthanide- and actinide-based compounds and environments in which various exotic phenomena can be studied in detail. Such phenomena include heavy fermion behavior (HF), superconductivity (SC), exotic magnetic ordering, the Kondo effect, valence fluctuations, non-Fermi liquid behavior (NFL), quantum criticality, among many others. Not only are these phenomena probed through measurements at extreme conditions like low temperatures down to 30 mK and high magnetic fields up to 65 T, but they are also studied as the electronic structure is modified through the substitution of atoms. By providing a detailed survey of certain correlated electron systems through multiple measurement techniques, we hope to better understand the underlying physical phenomena which drive the macroscopic behavior in these compounds which have been the subject of great interest for decades.
