CHENGDU - The Sichuan Yibin Port Economic Development Zone Industry Cooperation Fair was held in Yibin, Southwest China's Sichuan province, on Saturday, drawing 44 firms, chambers of commerce and international organizations from Japan, South Korea and other parts of China.   Some of them are Fortune 500 firms. They compared notes on development of the Yibin Port Economic Development Zone and sought business opportunities there.   On Friday afternoon, representatives of the...