doctoral – relating to the highest-ranking degree given by a university
expertise – expert skill or knowledge in a particular field
nanocomposite – denoting a composite material that has a grain size measured in nanometres
postdoctoral – being beyond the doctoral level: of or relating to advanced academic or professional work beyond a doctor’s degree or a postdoctoral fellowship.
energy density – is the amount of energy stored in a given system or region of space per unit volume
fluctuates or amount
– rise and fall irregularly in number