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Using side-dressing technique to reduce nitrogen leaching and improve nitrogen recovery efficiency u
The excessive nitrogen(N) fertilizer input coupled with flood irrigation might result in higher N leaching and lower nit......
目的:探讨宁夏县级医疗机构床位数的变化对机构规模效率的影响,从而发现宁夏县级综合医院适宜的规模。方法:以医疗机构的实际开放......
