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碳酸氢铵(化学式为NH4HCO3)是一种常用的化学肥料,白色晶体,易溶于水,受潮时在常温下就能分解,温度越高分解越快,分解产物为氨气、二氧化碳和水,因为草木灰的水溶液显碱性,所以不能和碳酸氢铵混合使用,在密闭的大棚内放置碳酸氢铵和稀盐酸,两者反应生成氯化铵、水和二氧化碳,二氧化碳可以促进植物的光合作用,而生成的氯化铵又可以作为氮肥再次使用.

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    The World Health Organization says the widespread use of sugar in food products and drinks is a major concern in many areas. So WHO officials are calling on governments to require taxes on sugary drinks in an effort to limit their usage and popularity. The officials believe the taxes also would reduce the risk of health problems resulting from obesity.

    Obesity is a condition in which the body stores large, unhealthy amounts of fat. Obese individuals are considered overweight. A new report says that in 2014 more than one-third of the adults in the world were overweight, and 500 million were considered obese. The United Nations agency estimates that in 2015, 42 million children under age 5 were either overweight or obese. It says that number represents an increase of about 11 million during the past 15 years. Almost half of these boys and girls live in Asia and one-fourth in Africa.

    The U.N. agency blames unhealthy diets for a rise in diabetes cases. There are 422 million cases of the disease worldwide. WHO says 1.5 million people die from it every year. It says the use of sugar in food products, like sugary drinks, is a major reason for the increase in rates of obesity and diabetes.

    Temo Waqanivalu is with the agency's Department for the Prevention on Non-Communicable Diseases. He told VOA hat taxing sugary drinks would reduce consumption and save lives. Waganivalu noted that Mexico enacted a 10 percent tax on sugary drinks in 2014. He said by the end of the year, there was a 6 percent drop in the consumption of such drinks. Among poor people, the number of people who consumed sugary drinks dropped by 17 percent.

    The WHO says people should limit the amount of sugar they consume. It says they should keep their sugar intake to below 10 percent of their total energy needs, and reduce it to less than 5 percent for improved health.