在DOSY NMR中使用信息标准进行自动化组件分析
Vladimir Palmin1, Andrey Mukhin1, Valeriya Ivanova1
1Moscow Institute of Physics and Technology (National Research University) - MIPT, 1 "A" Kerchenskaya st., Moscow, 117303, Russia.
Journal of magnetic resonance (San Diego, Calif. : 1997)
|September 9, 2023
概括
这项研究增强了扩散顺序光谱 (DOSY) 核磁共振 (NMR) 分析,使用贝叶斯信息标准进行组件检测. 后视最大值 (MAP) 和加权最小平方值 (WLS) 估计器在识别混合物成分方面显示出更高的准确性.
科学领域:
- 分析化学 分析化学
- 物理化学 物理化学
- 频谱学是一种光谱学.
背景情况:
- 扩散顺序光谱 (DOSY) 对于分析复杂混合物至关重要.
- 在DOSY NMR中精确估计混合物成分是具有挑战性的.
- 模型选择技术对于可靠的数据解释至关重要.
研究的目的:
- 为 DOSY NMR 引入使用贝叶斯信息标准的模型选择技术.
- 评估加权最小方程 (WLS) 和后期最大值 (MAP) 估计器的性能.
- 在混合物分析中确定这些估计器的准确性和局限性.
主要方法:
- 选择模型的贝叶斯信息标准.
- 权重最小平方 (WLS) 与L2规范化.
- 后期最大限度 (MAP) 具有先前信息数据库.
- 数据重新采样技术用于错误估计.
主要成果:
- WLS有效检测具有>2倍扩散系数差异的组件.
- MAP提高了精度,检测的组件有1.5倍的差异.
- 这两个估计器都产生了~1%标准偏差的权重比率估计.
- MAP可能会高估具有较大的自我扩散系数的组件.
结论:
- 开发的贝叶斯标准增强了DOSY NMR组件估计.
- WLS和MAP估计器在准确性和精度方面具有明显的优势.
- 根据检查的数据分布特征,可以进一步细化.
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