Determination of the p and Concentration of NMR-Invisible Molecules and Sites Using NMR Spectroscopy.

NMR spectroscopy is a very powerful tool for measuring the dissociation constants (p) of molecules, requiring smaller quantities of samples of lower purity relative to potentiometric or conductometric methods. However, current approaches are generally limited to those molecules possessing favorable pH-dependent NMR properties. Typically, a series of 1D experiments at varying pH are performed, and the p is obtained by fitting the observed chemical shift of the analyte as a function of pH using nonlinear routines.

Surface modification of cellulose nanomaterials with amine functionalized fluorinated ionic liquids for hydrophobicity and high thermal stability.

A highly hydrophobic fluorinated ionic liquid (IL), 3-aminopropyl-tributylphosphonium bis(trifluoromethylsolfonyl)imide ([aP][NTf]), was synthesized, and applied for the surface modification of cellulose nanomaterials (CNMs) by reductive amination. The modified CNMs were fully characterized for their chemical structure, morphology, thermal stability, and surface hydrophobicity. Results obtained from Nuclear Magnetic Resonance spectroscopy (H, C, F and P), Fourier Transform Infrared spectroscopy, X-ray Photoelectron Spectroscopy, and X-ray diffraction confirmed the successful grafting of [aP][NTf] onto the surface of CNMs up to a degree of surface functionalization of 2.

NaOH-assisted hydrothermal reduction of graphene oxide.

The influence of the pH of the reaction medium on the structural characteristics of hydrothermally reduced graphene oxide, synthesized by the tour method, has been investigated. Varying the pH of the reaction medium within the range of 8.0, 10.