ANOVA and factor analysis applied to time domain NMR signals
✍ Scribed by D. N. Rutledge; A. S. Barros; F. Gaudard
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 451 KB
- Volume
- 35
- Category
- Article
- ISSN
- 0749-1581
No coin nor oath required. For personal study only.
✦ Synopsis
Time domain (or low resolution pulse) NMR can generate a range of relaxation curves (CPMG, I-R, P-S, HSE, FID, etc.) which may vary depending on the characteristic of the product being controlledÈwater content, hydration state, solid fat content, iodine number or even authenticity of origin. Very often, the NMR signal is decomposed into a sum of exponential relaxation curves and the calculated NMR parameters (e.g. are R 1
, R 2 , M 0 ) correlated with the property under study. Chemometric techniques, such as analysis of variance (ANOVA) and factor analysis, were shown to be e †ective means of determining whether a given set of NMR signals contains any interesting information before proceeding to use fastidious and often uncertain signal decomposition procedures. These techniques were applied to NMR signals acquired for spreads and gelatines with di †erent compositions, to mixtures of a cation (Cu2') and a ligand (tetraphenylporphin) and to glycine solutions at di †erent pH values.