Evaluating the accuracy of absorbing aerosol optical properties measured using single particle cavity ring-down spectroscopy
Evaluating the accuracy of absorbing aerosol optical properties measured using single particle cavity ring-down spectroscopy
复制标题
评估使用单粒子腔衰荡光谱测量的吸收气溶胶光学特性的准确性
DOI：
10.1080/02786826.2023.2185500
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发表时间：
2023
影响因子：
5.2
通讯作者：
Knight J
中科院分区：
文献类型：
--
作者：
Knight J
单粒子空腔衰荡光谱(CRDS)可以直接和连续地测量组成恒定或不断变化的微米级悬浮气溶胶颗粒的消光截面。我们最近感兴趣的是关于光吸收粒子的单粒子CRDS测量。这些测量是对半径在1500-700 nm范围内蒸发的单个球形粒子进行的，这些粒子悬浮在405 nm腔体衰荡光谱仪中，使用线性电动四极杆陷阱。在这里，我们量化了我们的腔衰荡时间测量的准确性和精确度，以及在我们的电动陷阱内粒子运动的后果。接下来，我们估计从一定吸收强度范围内的颗粒的角度分辨弹性光散射测量中提取颗粒尺寸的不确定度。最后，我们评估了从同时测量的衰荡时间和颗粒大小中提取的复折射率值的准确性。这些评估考虑了测量的衰荡时间中的激发噪声和探测器噪声的影响、被驱动的粒子在电动陷阱内的运动以及粒子吸收强度(虚折射率在∼0.0-0.1范围内)。对于几乎所有被研究的吸收强度，以及对于成分恒定或不断变化的粒子，实数和虚数折射率的精度分别优于0.005和0.002。尽管限制在我们的电动四极陷阱中的粒子经历了相当程度的驱动运动(振荡幅度为几十微米)，但与粒子尺寸误差的贡献相比，这种运动对反演折射率不确定的贡献微不足道。
Single particle cavity ring-down spectroscopy (CRDS) allows direct and continuous measurements of the extinction cross-sections for levitated micron-scale aerosol particles of constant or evolving composition. Our recent interests have concerned single particle CRDS measurements for light-absorbing particles. These measurements are made on single, spherical particles evaporating over the radius range 1500–700 nm that are levitated within a 405-nm cavity ring-down spectrometer using a linear electrodynamic quadrupole trap. Here, we quantify the accuracy and precision of our cavity ring-down time measurements and the consequences of particle motion within our electrodynamic trap. Next, we estimate the uncertainty in our particle size retrievals from angularly resolved elastic light scattering measurements for particles with a range of absorption strengths. Finally, we assess the accuracy of complex refractive index values retrieved from simultaneous ring-down time and particle size measurements. The assessments account for the impacts of shot and detector noise in the measured ring-down times, the driven particle motion within the electrodynamic trap, and particle absorption strength (for imaginary refractive indices in the range ∼0.0–0.1). The real and imaginary refractive indices are retrieved to an accuracy better than 0.005 and 0.002, respectively, for almost all absorption strengths studied, and for particles of constant or evolving composition. Although particles confined in our electrodynamic quadrupole trap undergo considerable levels of driven motion (with oscillation amplitudes of several tens of micrometers), the contribution of this motion to uncertainty in retrieved refractive indices is negligible compared to contributions from particle sizing errors.
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影响因子：
5.2
作者：
Cotterell, Michael I.;Szpek, Kate;Langridge, Justin M.
通讯作者：
Langridge, Justin M.
影响因子：
2.9
作者：
Mason, B. J.;Cotterell, M. I.;Reid, J. P.
通讯作者：
Reid, J. P.
影响因子：
5.7
作者：
Walker, Jim S.;Carruthers, Antonia E.;Reid, Jonathan P.
通讯作者：
Reid, Jonathan P.
DOI：
--
发表时间：
1996
期刊：
影响因子：
--
作者：
O. Grineva;V. Zhuravlev;N. Lifanova
通讯作者：
N. Lifanova
DOI：
--
发表时间：
1956
期刊：
影响因子：
--
作者：
R. Simon
通讯作者：
R. Simon