英语语法分析

The yield of myrtenol (II) is a little improved by electron-transfer photooxygenation with dicyanoanthracene (DCA), but is almost double by the addition of biphenyl as cosensitizer.

二氰基蒽（DCA）敏化的电子转移光氧化使桃金娘烯醇的产率略有改善， 但是， 添加联苯作共敏化剂使产率几乎翻了一番。