Since the outbreak of SARS-COV-2, various virus inactivation techniques have been applied to suppress the spread of virus. Ultraviolet exposure inactivation is an efficient approach to inactivate virus, within UV band, UV-C with comparatively higher energy. UV-C has been proved to inactivate viruses efficiently, while to figure out efficient inactivation approach, virus reduction rate as a function of UV-C wavelength with different viral sensitivity and quantitative exposure dose should be measured through experiments. On the one hand, miniatured, energy-efficient and fully-customized UV-C light-emitting diodes (LED) offer possibility of switching wavelengths and adjusting quantitative optical properties, on the other hand, UV-C LEDs have been produced with the latest technology based on Aluminium gallium nitride (AlGaN). ~\Multifunctional UV-C LED Virus Inactivation Experimental Platform is a system designed with replaceable UV-C wavelengths, controllable light intensity and exposure time for quantitative virology experiments. The system has an initial design for standard virology experimental equipment which offers a new and consistent tool for virus researchers. The Inactivation Platform has been assembled and utilized to perform several Influenza A (ssRNA virus) inactivation experiments in order to obtain reduction rate as a function of UV-C wavelength and exposure dose with Germicidal Curve and Inactivation Curve respectively. ~\After inactivation experiments implementation and result analysis, the inactivation mechanism on the basis of molecular dynamic research theory and simulation is supposed to be figured out. Due to the complexity of proteins in virus, the research focuses on Nucleic Acid Bases (NABs) as target genetic viral material. The absorbed ultraviolet energy results in ultrafast decay, including molecular electronic transition, virus structure variation (Dimerization) theoretically. The absorbed energy along the band is revealed with Absorption Spectrum, and the potential electronic transition depends on the initial structure NABs, together with inside chemical bonds. When absorbed energy populates the molecules to transition state, ultrafast decay takes place because of the existence of Gibbs energy of activation. In the light of molecular dynamic simulation, it proves that compared to ground state, excited state leads to lower standard Gibbs energy of activation, causing higher reaction rate (faster inactivation speed).