Picture of smart phone in human hand

World leading smartphone and mobile technology research at Strathclyde...

The Strathprints institutional repository is a digital archive of University of Strathclyde's Open Access research outputs. Strathprints provides access to thousands of Open Access research papers by University of Strathclyde researchers, including by Strathclyde researchers from the Department of Computer & Information Sciences involved in researching exciting new applications for mobile and smartphone technology. But the transformative application of mobile technologies is also the focus of research within disciplines as diverse as Electronic & Electrical Engineering, Marketing, Human Resource Management and Biomedical Enginering, among others.

Explore Strathclyde's Open Access research on smartphone technology now...

Evaluation of low-field nuclear magnetic resonance spectrometry for at-line process analysis

Littlejohn, D. and Nordon, A. and McGill, C.A. (2002) Evaluation of low-field nuclear magnetic resonance spectrometry for at-line process analysis. Applied Spectroscopy, 56 (1). pp. 75-82. ISSN 0003-7028

Full text not available in this repository. Request a copy from the Strathclyde author

Abstract

A low-field medium-resolution NMR spectrometer, with an operating frequency of 29 MHz for 1H, has been developed for use in process analysis. The information that is attainable at this field strength has been investigated with the use of samples from a wide range of applications including the qualitative monitoring of a benzene production process, the estimation of the average ethoxy chain length in nonyl phenol ethoxylates, and the determination of strong acid concentrations. At low field, the spectra of multi-component samples often exhibit overlapping peaks, so multivariate calibration methods are necessary for quantitative analysis. Simulated data have been used to illustrate the effects of signal-to-noise ratio (SNR), resolution, and line shape on the predictive ability of partial least-squares (PLS) calibration routines, with SNR shown to have a greater impact than resolution on accuracy and precision. PLS calibration models were applied successfully in the analysis of samples from a methacrylamide process and a simulated esterification reaction. The accuracy (<5%) and precision (<3%) were generally good for components at concentrations >1-5% w/w.