The semi - automatic liquid nitrogen extracter is lowcost and easy - to - use , which can prevent the volatilization of the liquid nitrogen during the extraction 摘要介紹一種自制的半自動(dòng)液氮提取器,該提取器制作成本低廉,操作簡(jiǎn)單,并可以避免治療過(guò)程中提取液氮時(shí)液氮的大量揮發(fā),從而可以減少資源浪費(fèi),降低治療成本。