预测微塑料的垂直运输:形状和老化依赖的阻力模型
Chang Li1, Xue Bai2, Stefan Krause3
1Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
Journal of hazardous materials
|November 16, 2024
概括
这项研究开发了新的拖动模型,以预测微塑料 (MP) 如何在水中垂直移动. 这些模型准确地解释了MP的形状和老化,改善了环境风险评估的预测.
科学领域:
- 环境科学 环境科学
- 流体动力学 流体动力学
- 材料科学 材料科学 材料科学
背景情况:
- 准确预测微塑料 (MP) 垂直运输对于了解它们的环境命运和风险至关重要.
- 现有的拖动模型往往无法解释老化对MP属性和行为的影响.
- 对于老化微塑料,研究不足的阻力模型阻碍了全面的环境风险评估.
研究的目的:
- 开发和优化依赖形状和依赖衰老的阻力模型,用于预测微塑料的垂直沉积速度.
- 研究紫外线衰老对聚乙烯二甲 (PET) 和聚烯 (PS) 微塑料的物理化学特性和运输动态的影响.
- 提高阻力模型的适用性,以预测环境变化微塑料的运输.
主要方法:
- 使用原始和紫外线老化PET和PS微塑料进行了沉积实验.
- 结合了物理化学特性和运输数据,以优化使用Corey形状因子的形状依赖拖动模型.
- 通过结合碳基指数和新定义的衰老指数,开发了依赖衰老的阻力模型.
主要成果:
- 优化的依赖形状的模型在预测终端沉速度 (ut) 时实现了9.73% (PET) 和10.42% (PS) 的平均误差.
- 随着年龄的增长而变老的模型显示出更高的预测准确度,平均误差低至3.97% (PET) 和5.89% (PS).
- 开发的模型显示了更好的适用性,用于预测从环境中收集的经过气候变化的微塑料的垂直运输.
结论:
- 该研究提出了新的,准确的阻力模型,这些模型包含了微塑料的形状和衰老效应.
- 这些模型为预测微塑料环境行为提供了更好的科学支持,并为污染控制策略提供了信息.
- 进一步开发各种微塑料的运输数据库将提高预测能力和风险评估.
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