Search results for "Low field nuclear magnetic resonance"
showing 2 items of 2 documents
Guar gum/borax hydrogel: Rheological, low field NMR and release characterizations
2013
Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (ζ) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheological and Low Field NMR estimations of ζ lead to comparable results, while the drug release approach seems to underestimate ζ. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug…
Measuring hydrological connectivity inside a soil by low field nuclear magnetic resonance relaxometry
2017
Hydrological connectivity inside the soil is related to the spatial patterns inside the soil (i.e., the structural connectivity). This, in turn, is directly associated with the physical and the chemical processes at a molecular level (i.e., the functional connectivity). Nuclear magnetic resonance (NMR) relaxometry can be successfully applied to reveal both structural and functional components of soil hydrological connectivity. In the present study, the low field NMR relaxometry was applied on water suspended soils sampled at the upstream- and downstream-end of three different length plots. Also the sediments collected from the storage tanks at the end of each plot were water suspended and m…