玻璃可以热铸成型，省料省工
3Ag+4HNO3=3AgNO3+NO（g）=2H2O （稀硝酸）
Li Yan, an engineer, was born on February 9, 1965 in Beijing, China. After he graduated from Qinghua University in 1987, he made an important decision in his life. He decided to go to the United States for his further study. After four years hard work, he mastered new management ideas an advanced technologies in computer field. In 1992, he got his doctors degree. In 2008, he made another decision that to return to his motherland and started a company. However, his wife and daughter had got used to the American way of life, so they still stay in the United States. But they still can meet frequently, because of the convenient transportation, and his wife and daughter often visit him in holidays.