Search results for "FFC-NMR. Relaxometry"
showing 3 items of 3 documents
SUPRAMOLECULAR ORGANIZATION OF TRIGLYCERIDES IN EXTRA-VIRGIN OLIVE OILS AS ASSESSED BY NMR RELAXOMETRY
2010
Low resolution nuclear magnetic resonance (NMR) relaxometry revealed that triglycerides in extra-virgin olive oils are organized in inverse-micelle-like supramolecular structures held together by weak interactions such as van der Waals and hydrogen bonding. The formers can be established among the external apolar tails, while hydrogen bonds are present among the internal polar triglyceride heads, involving also the polar minor constituents of extra- virgin olive oils. The supramolecular assembly has been supported by experiments conducted by heating the samples in the NMR probe at four different temperatures. In addition all the oils were also added with increasing amounts of glacial acetic…
Reconstruction of the environmental evolution of a Sicilian saltmarsh (Italy)
2013
The present study deals with the reconstruction of the environmental evolution of a Trapani saltmarsh (southwestern Sicily, Italy) by combining different analytical approaches such as metal content evaluation, low-field nuclear magnetic resonance (NMR) relaxometry, and benthic foraminifera identification. A 41 cm core was collected in the sediments of a Trapani saltmarsh (southwestern Sicily, Italy) at a water depth of about 50 cm. Different time intervals were recognized, each characterized by peculiar features that testify different environmental conditions. In particular, the bottom layers of the sediment core (41–28 cm) comprised the lowest amount of mud fraction, only some selected met…
Dynamics of hyaluronan aqueous solutions as assessed by fast field cycling NMR relaxometry.
2010
Fast field cycling (FFC) NMR relaxometry has been used to study the conformational properties of aqueous solutions of hyaluronan (HYA) at three concentrations in the range 10 to 25 mg mL(-1). Results revealed that, irrespective of the solution concentration, three different hydration layers surround hyaluronan. The inner layer consists of water molecules strongly retained in the proximity of the HYA surface. Because of their strong interactions with HYA, water molecules in this inner hydration layer are subject to very slow dynamics and have the largest correlation times. The other two hydration layers are made of water molecules which are located progressively further from the HYA surface.…