最近客户总是问的一个问题：草甘膦30%， 360g/L， 480g/L， 41%到底有什么差异？
其实下面4个制剂是同一个产品，等同的。
Glyphosate30%SL( calculated as acid, w/w)
Glyphosate360g/L SL ( calculated as acid, w/v)
Glyphosate 41%SL(calculated as IPA, W/W)
Glyphosate480g/L SL (calculated as IPA, W/v)
和登记部沟通，具体答案见如下解释， 与同事一起分享，避免客户再遇到同样的问题。
41%草甘膦异丙胺盐水剂说明 Statement on Glyphosate IPA 41% w/w SL
草甘膦的分子量为169.07，草甘膦异丙胺盐的分子量为228.2，草甘膦异丙胺盐=1.349(即228.2/169.07=1.3497)*草甘膦含量。 即一升草甘膦水剂里面含有169.07g的草甘膦相当于一升草甘膦水剂里含有228.2g的异丙胺盐。 The ratio of the Mole Weight of Glyphosate-isopropylammonium salt and Glyphosate is 1.349 (228.2: 169.07 =1.349).
具体换算方法：
1.异丙胺盐和酸之间的换算：
IPA 41% w/w = Acid 30.39% w/w *1.349 (41% - active ingredient Isopropylamine Salt equivalent to 30% of free Acid Glyphosate)
IPA 480g/L = acid 355.8 g/L (~360 g/L)*1.349 （480g/l - active ingredient Isopropylamine Salt equivalent to 355.8g/L（~360g/L）of free Acid Glyphosate）
2. 单位表示方法间的换算
w/w =w/v*d (density 密度) w/v= d *(w/w) *1000
IPA 480 G/L =41% * d (1.17)*1000
Acid 360G/L =30.76%* d (1.17)*1000
Note: 41%草甘膦水剂的密度通常为1.16~1.175.
So in fact the products Glyphosate IPA 41% w/w SL, Glyphosate IPA 480g/L SL, Glyphosate 360g/L SL and Glyphosate 30% w/w SL are the same。