Motivated by engineering application of cryogenic helium as a coolant, as well as the generation of high Reynolds number turbulent flows due to its small kinematic viscosity, the development of effective visualization and velocimetry techniques is important. In this talk, I will discuss the development of helium molecular tracers that are created via femtosecond-laser field-ionization of helium atoms and can be imaged using a laser-induced fluorescence technique. This powerful velocimetry technique has been validated and applied to extract quantitative information about the flow field in cryogenic helium.  Besides, I will introduce high power target system at Facility for Rare Isotope Beams (FRIB). The facility is designed to reach beam on target power >400 kW for state-of-the-art rare isotope studies. Due to extremely high power density and heavy ion induced radiation damage on the material, one of the major challenges of the FRIB project is the design and integration of the high power target system. The status and future development of FRIB target system will be presented.