Urea was the only chemical that increased domoic-acid production .
只有在加入尿素时，海藻中的软骨藻酸含量增多。
Urea naturally breaks down into ammonia in the water .
尿素在水中会水解成氨。
Researchers serendipitously discovered that a mixture of urea , glycerol , and soap makes synthetic membranes transparent .
研究人员意外地发现一种由脲、甘油丙三醇和脂肪酸盐组成的混合物可以使合成的薄膜变得透明。
So he and his colleagues tested a range of chemicals found in fertilizers , including nitrate , ammonium and urea , to determine their effects on the algae .
他和同事们研究了肥料中的一系列化学物质，包括硝酸盐，铵和尿素，观察他们对海藻的影响。
When he refused to testify that a urea nitrate bomb had been the source of the explosion , the fbi found another lab technician to testify .
