在可变温度下对吸附气体运输的基于孔径的扩散率估计进行重新考虑
Chelsea W Neil1, Katherine C Swager1, S Michelle Bourret1
1Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87507, United States.
Environmental science & technology
|October 4, 2024
概括
高贵气体放射性同位素的检测证实了地下核爆炸. 了解气体运输,如和,通过地下材料对于准确的解释和改进的检测模型至关重要.
科学领域:
- 地质化学 地质化学
- 环境科学 环境科学
- 核科学 核科学 核科学
背景情况:
- 检测贵重气体放射性同位素是识别地下核爆炸的关键.
- 准确解释放射性同位素标记需要了解地下运输过程.
- 远场的扩散气体运输受到温度和石质学的影响.
研究的目的:
- 研究在高温下通过班德利尔的 (Xe), (Kr) 和硫六化物 (SF6) 的扩散运输.
- 确定扩散系数,并评估温度和吸附对气体传播的影响.
- 将实验结果与基于毛孔性的经验扩散估计进行比较.
主要方法:
- 使用了一种新开发的高温扩散电池.
- 使用有限元热量和质量传输代码模拟和参数ESTimation工具.
- 在20°C,40°C和70°C的温度下对完好无损的Bandelier进行了实验.
主要成果:
- 对于Xe,Kr和SF6的扩散系数在20°C时从2.6-3.1 × 10−6 m2/s到70°C时从4.3-7.0 × 10−6 m2/s不等.
- 吸附对环境温度 (20°C) 的运输产生了重大影响.
- 基于性的经验扩散估计没有准确地捕捉到这些气体在的观察到的大小或趋势.
结论:
- 实验运输调查对于理解地下气体传播至关重要.
- 升高的温度增加了贵重气体和SF6通过的扩散速度.
- 这些发现将加强核扩散检测和环境污染评估的模型.
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