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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
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Systematic bias in NMR diffusion measurements on polydisperse systems

Xiaoyue Zhou1, Kaipin Xu1, Shanmin Zhang1

  • 1Physics Department and Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai, China.

Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|February 15, 2015
PubMed
Summary

Least-squares fitting of the Stejskal-Tanner equation for molecular diffusion coefficient (MDC) measurement can be biased in polydispersed systems. This bias, dependent on distribution width and mean, affects accuracy, necessitating careful interpretation of results.

Keywords:
Diffusion coefficient distributionLeast-squares fittingMolecular diffusion coefficientNon-linear regression

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