Due to the effect of "colossal" magnetoresistance, bulk lanthanum manganites have become one of the most fashionable objects of investigations in solid state physics. This book illustrates that at radio frequencies, the magnetic permeability exceeds unity far above the temperature of the magnetic phase transition. Furthermore, it is demonstrated that radio-frequency properties of bulk lanthanum manganites can be useful for magnetoelectronic applications: sensors of static and high-frequency electromagnetic fields, non-linear devices with magnetic field modulation. In addition, lightening structural components is becoming more and more important for a lot of applications, particularly in the automotive and aerospace fields. In this book, a review of several recent studies about the effect of surface treatments on the fatigue and contact and rolling fatigue behaviour of different bulk materials is reported. Moreover, the chemical routes to elemental selenium and a number of metal chalcogenide materials are reviewed. Some of the synthesised materials characterised by their structural aspect and also their opto-electrical properties and sensing potentials were investigated. Other chapters investigate the advantageous applications of mercury cadmium tellurium in the military engineering and space technology, the electrical and mechanical properties for bulk polycrystalline materials, and the impact of the effective-mass theory on nanocrystal structures.