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- The present paper reviews biogeochemical cycle of nitrogen in agroecosystem. 根据国外资料,综述了有机农业土壤氮素流失规律与防止措施。
- Air consists chiefly of nitrogen. 空气主要由氮气组成。
- This is the cycle of economic booms and slumps. 这是经济繁荣和经济萧条的周期变化。
- He studied the cycle of events leading to the Great Depression. 他研究了导致大萧条的一系列事件。
- Using this product for long term, can efficiently avoid the suffocation of nitrification, promote the cycle of nitrogenous substance, avoid the water quality worsen and purify water quality, reduce the risk of breeding and increase the breeding benefit. 长期使用用本品后可有效避免硝化作用受阻、推动含氮物质的循环、避免水质恶化、净化水质降低养殖风险、提高养殖效益。
- The main reservoir of nitrogen is the atmosphere. 氮的主要蓄存库是大气层。
- What is the percentage of nitrogen in air? 空气中所含的氮的比例是多少?
- A cycle of the sun takes a year. 太阳循环周期需要一年。
- The crux of the matter was a lack of nitrogen. 问题的关键在于缺少氮。
- On the Business Cycle of the New Economy in U.S. 美国新经济周期研究。
- Is the cycle of economic booms and slumps. 这是经济繁荣和经济萧条的周期变化。
- A year constitutes a cycle of the seasons. 一年由四季的周期循环组成
- A single complete cycle of such motion. 旋转一圈
- Among the blue-green algae are many species of nitrogen fixation. 许多种蓝藻有固氮的能力。
- A single cycle of such a disturbance. 这种振动的一个周期
- Urea is commonly used as the source of nitrogen in foliage sprays. 尿素作为氮素给源普遍地应用于叶面喷布。
- One cycle of processing a body of data. 处理数据体的一个周期。参阅sortpass。
- The life cycle of clay is limited. 它的使用周期是有限的。
- The life cycle of Sparganum is unknown. 无头蚴（绦虫）属的生活史尚不了解。
- Has an atmosphere, which is mainly made up of nitrogen. 它拥有主要由氮组成的大气。
