To improve nitrogen (N) use efficiency and minimize environmental pollution caused by fertilizer overuse, novel bio-based large tablet controlled-release urea (LTCRU) was prepared using bio-based coating materials to coat large tablet urea (LTU) derived from urea prills (U). Nano fumed silica (NFS) was added to the bio-based coating materials to improve the slow-release properties. The surface area of the LTU and U was measured by three-dimensional scanning. In comparison to U, LTU had a smaller surface area/weight ratio, which can reduce the coating materials. Scanning electron microscopy analysis showed that the addition of NFS in bio-based coating materials reduced the porosity of the coating shells of LTCRUs and, thus, enhanced the N release longevity of the controlled-released fertilizer. Dependent upon the pores on the coating shells of LTCRU, two N release patterns were revealed. Because of the good release characteristics, the novel LTCRU shows great potential to support sustainable agricultural production.

中文翻译：

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生物基大片控制释放的尿素：合成，表征和控制释放的机制。

为了提高氮（N）的利用效率，并最大程度地减少因肥料过度使用而造成的环境污染，使用生物基包衣材料制备了新型生物基大片控释尿素（LTCRU），以涂覆源自尿素小球的大片剂尿素​​（LTU）。 （U）。将纳米气相法二氧化硅（NFS）添加到生物基涂料中，以改善缓释性能。LTU和U的表面积通过三维扫描测量。与U相比，LTU的表面积/重量比更小，可以减少涂层材料。扫描电子显微镜分析表明，在生物基包衣材料中添加NFS降低了LTCRUs包衣壳的孔隙率，从而提高了控释肥料的N释放寿命。取决于LTCRU涂层外壳上的孔，揭示了两种氮释放模式。由于具有良好的释放特性，新型LTCRU具有支持可持续农业生产的巨大潜力。