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尿素是氮、氢、碳、氧的化合物,其化学式为 NH_2CONH_2。纯尿素含氮46.7%。动物尿中有天然生成的尿素,厩舍中特有的氨味,就是由于地上及墙上残留的尿素迅速分解而放出氨气所产生的。尿素中由于含氮量很高(硫酸铵只含21%的氮),作为氮肥来说,是极引人注意的。现在,各国在加压下使氨与二氧化碳反应而合成的尿素,每年已达数百万吨。采用含氮量很高的尿素,可以大大节约施用和运输的成本,例如1磅尿素就差不多可以提供2磅硫酸铵所含的氮量。正如马来亚“植胶者通报”50期所指出的,尿素不含有和硫酸铵中硫酸根离子相当的酸性阴离子,因此,当施用等量的氮素时,尿素因释放出来的铵离子硝
Urea is a nitrogen, hydrogen, carbon, oxygen compounds, the formula is NH_2CONH_2. Pure urea nitrogen 46.7%. There are naturally occurring urea in animal urine, ammonia smell in the stables, which is caused by the rapid decomposition of residual urea on the ground and the release of ammonia. Urea due to high nitrogen content (ammonium sulfate contains only 21% of nitrogen), as a nitrogen fertilizer, is extremely attractive. Nowadays, urea, which is synthesized by the reaction of ammonia with carbon dioxide under the pressure, has reached millions of tons each year. The use of urea with a high nitrogen content can greatly reduce the cost of application and transportation. For example, 1 pound of urea provides about 2 pounds of nitrogen in ammonium sulfate. As pointed out in Malaya, “Transplanters Bulletin,” 50, urea does not contain acid anions that are comparable to sulfate ions in ammonium sulfate. Therefore, when an equivalent amount of nitrogen is applied, the urea is released by ammonium ions