Safety is a very crucial thing among the experiments of GEC-CHINA. Before doing the experiment, we had already learned some knowledge about lab safety and we knew how to solve some simple but accidental issues during the experiment. In addition, two teachers would supervise us during the process of the experiments. They demonstrated the operation of some complex machines step by step. So, our experiment was conducted in a very safe environment. There are no ethical issues in our experiment because we did not use human or animals as the experiment object. Also, all the pictures, data and videos we use in human practice are recorded by the person who engaged in the project. All of our activities are conducted in a proper environment.