使用聚合物添加剂控制滴滴沉积
1Rhodia Recherches, Centre de Recherches Lyon, Saint-Fons, France. vance.bergeron@rhone-poulenc.com
Nature
|June 24, 2000
概括
将柔性聚合物添加到喷雾剂中可以防止水滴从植物叶子上反弹. 这项创新增强了农药和除草剂的沉积,改善了向的交付和减少对环境的影响.
科学领域:
- 流体动力学 流体动力学
- 材料科学 是一种材料科学.
- 农业科学 农业科学
背景情况:
- 控制滴滴的影响对于涂层,沉积和农业应用,如农药喷至关重要.
- 植物叶子具有疏水性,状的表面,导致喷的水滴反弹,导致保持不良 (通常<50%).
- 现有关于滴滴对疏水表面的影响的研究主要考虑牛顿流体,忽视非牛顿效应.
研究的目的:
- 研究抑制水表面滴滴反弹的方法.
- 为了提高农业喷雾中的滴滴沉积效率.
- 探索非牛顿流体特性在滴滴撞击动态中的作用.
主要方法:
- 用少量的柔性聚合物配制水溶液.
- 对这些聚合物溶液在疏水表面进行冲击实验.
- 使用实验和理论方法分析滴水的行为,反弹和沉积.
- 测量剪切粘度以确认最小的变化.
主要成果:
- 添加柔性聚合物显著抑制了水表面上的滴滴反弹.
- 滴滴沉积效率明显提高,但剪切粘度没有显著变化.
- 观察到的效应归因于聚合物溶液的非牛顿延长粘度.
结论:
- 灵活的聚合物可以有效地抑制不湿表面的滴滴反弹.
- 非牛顿延伸粘度在防止滴滴收缩和反弹方面发挥着关键作用.
- 这种方法为改善农业和其他领域的喷雾沉积提供了一个有希望的策略.
相关概念视频
Precipitate Formation and Particle Size Control
In precipitation gravimetry, the precipitating agent should react specifically or selectively with the analyte. While a specific reagent reacts with the analyte alone, a selective reagent can react with a limited number of chemical species.
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...
Colloidal precipitates
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...


