文献里面 in one portion 是什么意思？
To a mixture of 3-(2-ethylhexyl)thiophene (1.96 g, 10 mol) and anhydrous THF (20 mL) cooled in a liquid nitrogen/acetone bath was added 2.5 M n-butyl lithium (10 mmol, 4 mL) dropwise over 15 min. After stirring for 2 h at -78 oC, trimethyl borate (1.04 g, 10 mmol) was added in one portion。
我不太理解，这个in one portion 是指一次性快速加入吗？还是一次性加入就行，不管是快速加入还是滴加？
