尿素是重要氮素化肥之一,它具有较多的优点。首先,它的性质稳定,不会损失养分,易于贮藏。例如,用失重法测定,把尿素摊开,放入25℃温箱中,10天后只减重0.02%;在0℃左右的低温下,10天后反而增重0.04%。这种微小的变化,只不过是水分的增减罢了,本身的养分并没有损失。其次,它的含氮量高达46%,是固体氮肥中含氮量最高的,因而含等氮的肥料,它的体积就小得多,这样就便于长途运输。第三,尿素肥料产品,通常 Urea is one of the important nitrogen fertilizers, it has many advantages. First, it is stable in nature, does not lose nutrients and is easy to store. For example, by weight loss method, the urea spread out into the 25 ℃ incubator, only 10 days after the weight loss of 0.02%; at 0 ℃ low temperature, but after 10 days the weight gain 0.04%. This slight change is nothing more than the increase or decrease of water, but no loss of nutrients. Second, its nitrogen content is as high as 46%, which is the highest nitrogen content in solid nitrogen fertilizers, and therefore contains nitrogenous fertilizers which are much smaller in size and thus easier to transport long distances. Third, urea fertilizer products, usually