Search results for "FFC-NMR relaxometry"
showing 5 items of 5 documents
Evaluation of adsorption ability of Cyclodextrin-Calixarene Nanosponges towards Pb2+ ion in aqueous solution
2021
Abstract Different cyclodextrin-calixarene nanosponges (CyCaNSs) have been characterized by means of FFC-NMR relaxometry, and used as sorbents to remove Pb2+ ions from aqueous solutions. Considering that the removal treatments may involve polluted waters with different characteristics, the adsorption experiments were performed on solutions without and with the addition of background salts, under different operational conditions. The adsorption abilities and affinities of the nanosponges towards Pb2+ ions were investigated by measuring the metal ion concentration by means of Inductively Coupled Plasma Emission Spectroscopy (ICP-OES) and Differential Pulse Anodic Stripping Voltammetry (DP-ASV…
Water Dynamics at the Solid-Liquid Interface to Unveil the Textural Features of Synthetic Nanosponges.
2020
A Fast-Field-Cycling NMR investigation was carried out on a set of polyurethane cyclodextrin nanosponges, in order to gain information on their textural properties, which have been proven to be quite difficult to assess by means of ordinary porosimetric techniques. Experiments were performed on both dry and wet samples, in order to evaluate the behavior of the “non-exchangeable” C-bound 1H nuclei, as well as the one of the mobile protons belonging to the skeletal hydroxyl groups and the water molecules. The results acquired for the wet samples accounted for the molecular mobility of water molecules within the channels of the nanosponge network, leading back to the possible pore size distrib…
Effect of Organic Amendments on the Evolution of Soil Organic Matter in Soils Stressed by Intensive Agricultural Practices
2013
Losses of soil organic carbon often occur because of intensive agricultural practices that lead to removal of organic carbon following harvest production and to insufficient inputs. Organic amendments can be a very appropriate matrix for enhancing organic carbon content in very stressed agricultural soils. In general, they, enhancing soil organic matter, play an important role in environmental matrices due, for example, to their capacity in retaining water, in interacting with organic and inorganic pollutants, and in enhancing nutrient availability to plants. For this reason, the understanding of the mechanisms with which organic amendments interact with other chemicals in the environment i…
Solid-state 1H-NMR relaxation properties of the fruit of a wild relative of eggplant at different proton Larmor frequencies
2009
1H longitudinal relaxation time profiles (T1) at different proton Larmor frequencies were registered for a solid state plant tissue by using fast field cycling (FFC) nuclear magnetic resonance (NMR) spectroscopy. T1 distributions were obtained and the curves deconvoluted in order to differentiate among the different T1 components. Among the components, two were assigned to hydrophobic (e.g. fatty acids) and hydrophilic (e.g. saccharides) molecular systems, whereas the remaining others were attributed to bulk and bound water. This paper showed for the first time solid state FFC-NMR spectroscopy applied to plant tissue, and revealed that relaxometry is a very promising technique for studying …