You will have difficulty in getting a new position in China. Most schools require a reference letter from previous employee ( actually it is a release letter). If you leave a school without adequate notice then the school will probably not want to provide you the letter. Also you run the risk of having your Z visa and residency permit canceled which means that you will be in the country illegally. I would strongly suggest that you do the right thing and give appropriate notice. While schools may be reluctant, most reputable schools will do so.