China National Offshore Oil Corp. (CNOOC) is in talks with potential investors about the stock-market listing of its chemical fertilizer unit to raise as much as 400 million US dollars, The Wall Street Journal reported. China Blue, which aims to list on the Hong Kong stock exchange Sept. 29, also intends to sell part of the offering to some tycoons in that city, said the paper, quoted a market source as saying. China's demand for chemical fertilizers is strong, because farmers need to raise crop yields to feed the fast-growing population. According to the China Petroleum and Chemical Industry Association, China's investment in nitrogenous fertilizer in the first half of this year rose 33% from a year earlier. China Blue, based in the southern province of Hainan, plans to use part of the IPO proceeds to upgrade its facility in Inner Mongolia.