环保设备板块12月31日涨0.4%，碧兴物联领涨，主力资金净流出1.35亿元

Group 1 - The environmental equipment sector increased by 0.4% on December 31, with Bixing Wulian leading the gains [1] - The Shanghai Composite Index closed at 3968.84, up 0.09%, while the Shenzhen Component Index closed at 13525.02, down 0.58% [1] - Key stocks in the environmental equipment sector showed various performance metrics, with Bixing Wulian closing at 24.77, up 5.27% [1] Group 2 - The environmental equipment sector experienced a net outflow of 135 million yuan from institutional investors, while retail investors saw a net inflow of 62.43 million yuan [2] - The trading volume and turnover for key stocks in the sector varied, with Xuedilong having a turnover of 262 million yuan and a closing price of 9.03, up 4.03% [2] - The stock performance of various companies showed mixed results, with some stocks like Xuedilong and Henghe Co. experiencing significant fluctuations in net inflows from different investor types [3]