string(271) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E6%B3%A2%E7%BA%B9%E7%AE%A1ad13%E6%98%AF%E5%A4%9A%E5%A4%A7%E7%9B%B4%E5%BE%84%E7%9A%84%E7%AE%A1%E5%AD%90 => Failed to connect to 101.89.143.195 port 38109: Connection refused"
波纹管ad13是多大直径的管子
