4. Effective in heat removing and broad operating temperature: most of photoreactions are carried out under ambient temperature and atmospheric environment. The reaction should be motivated only by the photon excitation and free of the thermal path, therefore the effect of temperature should be minimized. As a result, air or liquid cooling is necessary. 5. Flexibility in the use of different types of reaction containers and ease to work with the flow conditions: the reaction containers in use can be arbitrarily assigned and the test rig can work in flow without too much additional effort.