Inter‐instrument comparison of particle‐size analysers
Inter‐instrument comparison of particle‐size analysers
复制标题
粒度分析仪的仪器间比较
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
G. Weltje
中科院分区：
文献类型：
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作者：
S. Roberson;G. Weltje
本文提出了一种用于不同粒度分析仪的仪器间比较的方法框架。该框架包括：（i）量化完整粒度分布之间的差异;（ii）确定由不同仪器测量的粒度分布的最佳回归模型;（iii）量化一系列粒度分析仪的精度;（iv）确定用于分析给定样品组的最合适仪器。在整个研究中，对粒度分布应用对数比变换，以避免在“封闭空间”中分析百分比频率数据的陷阱。标准化距离统计量用于量化粒度分布之间的差异，并评估对数比回归模型的性能。46种不同的回归模型应用于通过筛吸和激光分析测量的沉积物样品。交互式二次回归模型提供了将不同仪器测量的粒度分布数据集转换为可比格式的最佳方法。然而，与线性回归模型（n = 50）相比，二次交互对数比回归模型需要大量的训练样本（n > 80）才能实现最佳性能。使用由四个先前发表的粉质沉积物样品制成的十个重复测量的数据集来评估十个粒度分析仪器的精度。仪器精密度量化为对每个沉积物样品进行的十次重复测量之间测量的中值归一化差异。引入区分能力统计来评估每个仪器检测四个沉积物样品之间差异的能力。区分能力分数表明，基于激光衍射原理的仪器能够在95%的置信水平下最有效地区分粉质沉积物样品。应用沉积原理的仪器提供了下一个最精确的方法。
This paper presents a methodological framework for inter‐instrument comparison of different particle‐size analysers. The framework consists of: (i) quantifying the difference between complete particle‐size distributions; (ii) identifying the best regression model for homogenizing data sets of particle‐size distributions measured by different instruments; (iii) quantifying the precision of a range of particle‐size analysers; and (iv) identifying the most appropriate instrument for analysing a given set of samples. The log‐ratio transform is applied to particle‐size distributions throughout this study to avoid the pitfalls of analysing percentage‐frequency data in ‘closed‐space’. A Normalized Distance statistic is used to quantify the difference between particle‐size distributions and assess the performance of log‐ratio regression models. Forty‐six different regression models are applied to sediment samples measured by both sieve‐pipette and laser analysis. Interactive quadratic regression models offer the best means of homogenizing data sets of particle‐size distributions measured by different instruments into a comparable format. However, quadratic interactive log‐ratio regression models require a large number of training samples (n > 80) to achieve optimal performance compared to linear regression models (n = 50). The precision of ten particle‐size analysis instruments was assessed using a data set of ten replicate measurements made of four previously published silty sediment samples. Instrument precision is quantified as the median Normalized Difference measured between the ten replicate measurements made for each sediment sample. The Differentiation Power statistic is introduced to assess the ability of each instrument to detect differences between the four sediment samples. Differentiation Power scores show that instruments based on laser diffraction principles are able to differentiate most effectively between the samples of silty sediment at a 95% confidence level. Instruments applying the principles of sedimentation offer the next most precise approach.