Yes you can. As long as you enter China before the expiration date, you can stay for 30 to 60 days as specified on your visa. Duration of stay start from the day you enter China.
Find more information directly at:
China Embassy
Source & Copyright: The source of the above visa and immigration information and copyright owner/s is the:
Country : China
– Ministry of Foreign Affairs, the People’s Republic of China – URL: www.fmprc.gov.cn
– Embassy of the Peoples Republic of China in the United Kingdom – URL: www.chinese-embassy.org.uk
– Embassy of People’s Republic of China in the United States of America – URL: www.china-embassy.org