H-SHARE companies benefited from a surge of buying interest yesterday. The mainland companies listed on the exchange in Hong Kong took the top three slots for the most active stocks by share volume. Of the top 10, seven were either H-share or back-door-listed companies. They also took three of the top 10 rankings as performers of the day. By share volume Yizheng Chemical, which on Thursday announced bumper results, was the most active stock. It rose three per cent or eight cents to $2.53 on a turnover of 40.74 million shares amounting to $102.62 million, making it the seventh most active stock by value. Shanghai Petrochemical was in second place by share volume, rising 5.9 per cent or 13 cents to $2.32. This performance made it the fifth best performing stock of the day. The share volume was 23.08 million shares. In third place by share volume was Maanshan Iron & Steel with 12.81 million shares traded. The share rose 10 cents or 3.89 per cent to $2.67. Filling places seven to 10 were Shougang International, a back-door listing; Qingling Motors; Guangdong Investment, a Hong Kong-incorporated mainland investment vehicle; and Paragon, another back-door listing. Respectively, they saw volumes of 7.26 million, 7.04 million, 7.02 million and 6.85 million shares. Shougang rose four cents to $2.48, Qingling added five to $2.61, Guangdong Investment fell 7.5 cents to $5.025, and Paragon edged up 0.6 cent to 31.9 cents. Of the best performers, Kunming Machine, which announced results yesterday, ranked second for the day. It was up 28 cents or nine per cent to $3.40. Guangzhou Shipyard also was busy, rising 16 cents to $3.44. After suffering from poor sentiment in the past few months, a more optimistic view of China's economic situation has led some overseas investors to take another glance at these companies.