Nanyang Technological University and Berkeley Education Alliance for Research in Singapore , Singapore 639798.
Environ Sci Technol. 2014 Apr 1;48(7):3682-90. doi: 10.1021/es4051956. Epub 2014 Mar 12.
Models of reactive uptake of ozone in indoor environments generally describe materials through aerial (horizontal) projections of surface area, a potentially limiting assumption for porous materials. We investigated the effect of changing porosity/pore size, material thickness, and chamber fluid mechanic conditions on the reactive uptake of ozone to five materials: two cellulose filter papers, two cementitious materials, and an activated carbon cloth. Results include (1) material porosity and pore size distributions, (2) effective diffusion coefficients for ozone in materials, and (3) material-ozone deposition velocities and reaction probabilities. At small length scales (0.02-0.16 cm) increasing thickness caused increases in estimated reaction probabilities from 1 × 10(-6) to 5 × 10(-6) for one type of filter paper and from 1 × 10(-6) to 1 × 10(-5) for a second type of filter paper, an effect not observed for materials tested at larger thicknesses. For high porosity materials, increasing chamber transport-limited deposition velocities resulted in increases in reaction probabilities by factors of 1.4-2.0. The impact of physical properties and transport effects on values of the Thiele modulus, ranging across all materials from 0.03 to 13, is discussed in terms of the challenges in estimating reaction probabilities to porous materials in scenarios relevant to indoor environments.
室内环境中臭氧的反应性吸收模型通常通过表面积的空中（水平）投影来描述材料，这对于多孔材料来说是一个潜在的限制假设。我们研究了改变多孔性/孔径、材料厚度和腔室流体力学条件对五种材料（两种纤维素滤纸、两种水泥基材料和一种活性炭布）的臭氧反应性吸收的影响。结果包括：（1）材料的孔隙率和孔径分布；（2）臭氧在材料中的有效扩散系数；以及（3）材料-臭氧沉积速度和反应概率。在小的长度尺度（0.02-0.16 厘米）下，增加厚度导致一种类型的滤纸的估计反应概率从 1×10(-6)增加到 5×10(-6)，另一种类型的滤纸从 1×10(-6)增加到 1×10(-5)，而在较大厚度下测试的材料则没有观察到这种效果。对于高多孔性材料，增加腔室输送限制的沉积速度会导致反应概率增加 1.4-2.0 倍。讨论了物理性质和传输效应对 Thiele 模量值（所有材料的范围从 0.03 到 13）的影响，这对于在与室内环境相关的场景中估计多孔材料的反应概率提出了挑战。
