In a pre-process, a particle shape substance is decomposed and removed using a cyclone and an electric dust collection apparatus, NOx in an exhaust gas is decomposed completely using discharge, to establish technique for generating NO2 for necessary to oxidize a particle shape substance in a real time. For example, at least one of the received IP addresses may be encoded into a respective MAC address. The cover defines at least one opening for receiving an input tube therethrough such that raw materials, reagents, gases and products can be introduced into or removed from the test tube. The invention aims to provide a valve with a compact construction.