Nuclear magnetic resonance spectroscopy pulsed field-gradient

Lead, J. R., Wilkinson, K. J., Balnois, E., Cutak, B. J., Larive, C. K., Assemi, S., and Beckett, R. (2000). Diffusion coefficients and polydispersities of the Suwannee River Fulvic Acid Comparison of fluorescence correlation spectroscopy, pulsed-field gradient nuclear magnetic resonance, and flow field-flow fractionation. Environ. Sci. Technol. 34(16), 3508-3513. 

Lead JR, Wilkinson KJ, Balnois E, Cutak BJ, Larive CK, Assemi S, Beckett R Diffusion Coefficients and Polydispersities of the Suwannee River Fulvic Acid Comparison of Fluorescence Correlation Spectroscopy, Pulsed-Field Gradient Nuclear Magnetic Resonance, and Flow Field-Flow Fractionation. Environ Sci Technol 2000, 34 3508-3513. 

The porosity is not a separate factor for diffusion measurements using techniques such as pulsed field gradient nuclear magnetic resonance spectroscopy and some modes of quasielastic light scattering in which the diffusivity is determined from the mean-square displacement of solutes ... 

A polyethyleneoxide-Z)-polydimethylsiloxane-polyethyleneoxide surfactant, (EO)i5-(DMS)i5-(EO)i5, was studied with freeze-fiacture transmission electron microscopy and pulsed-field gradient nuclear magnetic resonance spectroscopy, in order to establish the effect of glycerol on the permeability of vesicle membranes. Small vesicles with diameters of less than 25 nm and multilamellar vesicles with diameters larger than 250 nm were observed in pure water, which were modified when water was gradually replaced with glycerol [47],... 

Price, W.S. 1998a. Pulsed-field gradient nuclear magnetic resonance as a tool for studying translational diffusion. II. Experimental aspects. Basic theory. Concepts in Magn. Reson. 10, 197-237. Price, W.S. 1998b. NMR imaging. In Annual Reports on NMR Spectroscopy (G.A. Webb, ed.), Vol. 34, pp. 140-216. Academic Press, New York. 

Various new techniques suitable for estimating D are now available fluorescence correlation spectroscopy (FCS) [5], fluorescence recovery after photobleaching (FRAP) [6], pulsed field gradient nuclear magnetic resonance (PFG-NMR) [7], diffusion ordered NMR spectroscopy (DOSY) [8], and others. Among these, FCS and FRAP are popular in biological studies because they are often installed on a commercial LSM system and conveniently coupled with it. 

This review presents recent developments in the application of nuclear magnetic resonance (NMR) spectroscopy to study ionic liquids. In addition to routine structural characterization of synthesized ionic liquids, availability of multitude of advanced NMR techniques enables researchers to probe the structure and dynamics of these materials. Also most of the ionic liquids contain a host of NMR-active nuclei that are perfectly suitable for multinuclear NMR experiments. This review focuses on the application of NMR techniques, such as pulsed field gradient, relaxometry, nuclear Overhauser effect, electrophoretic NMR, and other novel experiments designed to investigate pure ionic liquids and the interaction of ionic liquids with various salts and solutes. 

As a qualitative means to investigate the ionic nature of acid-base systems, various techniques have been employed such as one- or two-dimensional nuclear magnetic resonance (NMR) spectroscopy [31], infrared (IR) spectroscopy [32], the Walden plot [33], the ratio of molar conductivities AjmpMNMR (determined by electrochemical impedance spectroscopy and pulse-field-gradient spin-echo NMR, respectively) [34], Some of these will be discussed below. 

Apart from electrochemical characterisation, a set of spectroscopic techniques is very useful. These are infrared (IR) (Marcinek et al. 2004), Raman (Marcinek et al. 2005) and nuclear magnetic resonance (NMR) (Berthier et al. 1983 Dai et al. 1998) spectroscopies. These allow observation of the interactions among electrolyte components, as well as providing chemical information about their structure. Pulse field gradient (PEG) NMR (Gorecki et al. 1988) is also used for observation of mass transport properties. 

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