午盘收盘，国内期货主力合约涨跌不一。铝合金涨超4%，苯乙烯（EB）涨超2%。跌幅方面，不锈钢（SS）、沪锌、尿素、沪镍跌超1%。

Core Viewpoint - Domestic futures main contracts showed mixed performance at midday, with aluminum alloy rising over 4% and styrene (EB) increasing over 2%, while stainless steel (SS), Shanghai zinc, urea, and Shanghai nickel fell over 1% [1] Group 1 - Aluminum alloy experienced a significant increase, rising more than 4% [1] - Styrene (EB) also saw a positive movement, with an increase of over 2% [1] - Several commodities faced declines, including stainless steel (SS), Shanghai zinc, urea, and Shanghai nickel, each dropping more than 1% [1]