Scientists say an experimental vaccine reduced the risk of infection in human beings by thirty-one percent and was safe.

VOA: special.2009.10.13

Is never going to be the most convenient one experimental.

试验中要保持熵恒定,是非常不方便的。

麻省理工公开课 - 热力学与动力学课程节选

Scientists say an experimental vaccine reduced the risk of infection in humans by thirty-one percent and was safe.

VOA: special.2009.09.30

Russia's Pavlovsk Experimental Station houses one of the oldest seed and plant collections in the world.

VOA: special.2010.08.24