BEIJING, April 29 (Xinhua) -- Chinese shares concluded Tuesday trading slightly higher, with brokers, power, energy sectors leading the upward movement.

    But the impending unlocking of large amount of non-tradable equities dampened market sentiment and drove the upward adjustment to a halt, market observers said.

    In May, there will be formerly non-tradable shares valued at 230 billion yuan (32.9 billion U.S. dollars) becoming negotiable, which will add to pressure on liquidity and threaten investors' enthusiasm, the observers added.

    On Tuesday, China Aluminum Industry, one of the top 10 heavyweights, lost 1.36 percent to 21.11 yuan, as it will have 2.5billion non-tradable shares to become negotiable on Wednesday.

    However, Bank of China and PetroChina, also included in the top10, performed well on release of their quarterly corporate results.

    Bank of China, a leading commercial bank, reported a 78 percent growth in net profits for the first quarter of this year, while PetroChina, the nation's largest oil producer, unveiled higher-than-expected quarterly earnings -- though its net profits declined 29 percent, its earnings per share stood at 0.14 yuan, higher than the market-anticipated 0.08 yuan.

    The bank rose 2.41 percent to 5.09 yuan, while the oil company, up 1.31 percent to 17.06 yuan.

    Meanwhile, the broker, power and energy sectors performed in an impressive manner.

    Guojin Securities and Jidian Electricity rose by the 10-percentdaily limit. Changjiang Securities gained 9.98 percent and Pacific Securities increased by more than eight percent. Huaneng International, a leading power supplier, went up 8.04 percent, and Guodian Electricity, soared 8.86 percent.

    On Tuesday, the benchmark Shanghai Composite Index ended the daily trading at 3,523.41 points, 48.68 points, or 1.40 percent, higher than the previous close.

    The Shenzhen Component Index for the smaller stock exchange in Shenzhen gained 98.38 points, or 0.77 percent, to close at 12,880.88 points.

    Combined turnover on the two bourses shrank further to 145.42 billion yuan (20.8 billion U.S. dollars), down from 161.2 billion yuan for the previous trading day.

    Gains outnumbered losses by 582 to 229 in Shanghai and by 443 to 186 in Shenzhen.