found 2 in 59ms
patent
score
priority
expiry  
expired
references
current assignee
title
D93862092019-12-042036-12-1403NINGBO HELONG NEW MATERIAL CO., LTD;  WPC panel
10577770962017-06-302037-11-0600ZHEJIANG UNIVERSITY;  Self-starting negative pressure drainage system for draining groundwater in slope and construction method thereof