My major I major in thermal energy engineering, and my research subject is seawater desaliantion utilizing multi-effect distillation.You may ask that why you chose this for your research suject? You can see the date as follow:only 0.25% water in the earth is fresh one, and among which, no more than 1% can be used directly,what's more, in 2025, 3,000,000,000 people will live in the shortage of fresh water. That how to get pure water from sea is a focus topic in the filed of water treatment, because of the serious reduction of the water resourse.