1.There is little study on the selection of liquid of pre - filming after the acid wash by hydroxy ethidine phosphonic acid (HEDP).
羟基叉二膦酸酸洗后预膜液的选择较少有人研究,而适当的预膜钝化是防止酸洗后金属表面返锈的必要措施。
2.Abstract A method is suggested to determine the absolute configuration of ent kaurene diterpenoids by analysing the circular dichroism spectral data of 13 hydroxy ent kaurenoids.