在平衡状态中集成的建模时间尺度被动抽样
Oindrila Ghosh1, Songjing Yan1, Mandar Bokare1
1Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland Baltimore County, Baltimore, MD, United States.
Environmental toxicology and chemistry
|January 31, 2025
概括
被动采样器 (PSs) 为环境风险评估提供时间平均污染物度. 本研究模拟了多二的集成采样时间尺度 (TSI),发现它因化合物的疏水性和采样器厚度而异.
科学领域:
- 环境化学环境化学
- 分析化学 分析化学
- 环境科学 环境科学
背景情况:
- 被动采样器 (PSs) 测量时间平均污染物度,这对于评估生态暴露和估计污染物负载至关重要.
- 准确地解释PS数据需要对采样时间表的整合 (TSI) 有充分的了解.
研究的目的:
- 进行全面的理论建模评估,以评估采样技术标准的平衡被动采样.
- 在低密度聚乙烯 (PE) 被动样本中模拟多化双同源的交换动力学.
主要方法:
- 在PE被动样本中模拟多双类同源的扩散运输和第一阶动力学.
- 通过模拟90天内脉冲度增加的情况来评估采样 TSI.
- 分析化合物疏水性和采样器厚度对 TSI 的影响.
主要成果:
- 更多的疏水化合物表现出较慢的传输速率和较长的 TSI.
- 与较薄的样本相比,较厚的样本显示出较长的TSI.
- 使用25.4微米PE板的TSI从二二烯的14-15天到六二烯的43-45天不等.
结论:
- 采样 TSI 受污染物的特性和被动采样者的特征的影响.
- 粗细的被动采样器的战略部署可以完善 TSI 估计.
- 这种方法可以同时捕获偶发事件和长期平均污染物度.
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