采用驻波管法测量了多种粮食的吸声系数。
Methods Use a standing wave tube to measure the sound absorption coefficient of many kinds of grain.
白蚁们在堡垒中抚养着幼蚁，有时甚至在堡垒中种粮食。
Inside these fortresses, the termites rear their young - and in some cases even grow their own crops.
你知不知道，如果我们把土地用来种粮食而不养家禽的话。
应用推荐