Models for humic and fulvic acids are discussed based on 13 C liquid state NMR spectra combined with results from elemental analysis and titration studies. The analysis of NMR spectra is based on a full reconstruction of the NMR spectrum done with help of 13 C-NMR data bases by adding up chemical shifts of all substructures from the proposed models. A full reconstruction makes sure that all car...

The combination of structural diversity at several levels and limited chemical shift dispersion ensures that NMR spectra of carbohydrates are relatively difficult to interpret. This introduction to applications of NMR spectroscopy for the study of carbohydrates provides guidelines for interpretation of their 1and 2-D spectra against a background of their tautomeric, configurational, and conform...

Standard methods for de novo protein structure determination by nuclear magnetic resonance (NMR) require time-consuming data collection and interpretation efforts. Here we present a qualitatively distinct and novel approach, called Comparative, Objective Measurement of Protein Architectures by Scoring Shifts (COMPASS), which identifies the best structures from a set of structural models by nume...

The aminolysis of (NPCl2)2NSOPh by methyland ethylamine in diethylether proceeds mainly via a non-geminal substitution pattern. In acetonitrile both geminal and nongeminal substitution is observed. The preparation of the derivatives is described and the iH and 3 1P NMR data are discussed. The interpretation of the NMR spectra is supported by the simulation of the spectra of NPClNHMeNPCl2NSOPh.

A simple modification of the WATERGATE solvent suppression method greatly improves the quality of (1)H NMR spectra obtainable from samples in H(2)O. The new method allows (1)H signals to be measured even when close in chemical shift to the signal of water, as for example in the NMR spectra of carbohydrates.

We demonstrate the acquisition of ultrafast 2D NMR spectra of semi-solid samples, with a high-resolution magic-angle-spinning setup. Using a recent double-quantum NMR pulse sequence in optimised synchronisation conditions, high-quality 2D spectra can be recorded for a sample under magic-angle spinning. An illustration is given with a semi-solid sample of banana pulp.

The unique high-resolution feature offered by 14N magic-angle spinning (MAS) NMR spectroscopy of ammonium ions has been used to characterize the crystal structures of various ammonium molybdates by their 14N quadrupole coupling parameters, i.e., CQ, the quadrupole coupling constant, and etaQ, the asymmetry parameter. Two polymorphs of diammonium monomolybdate, (NH4)2MoO4, recently structurally ...

Combinatorial techniques which provide information on intensity and signal patterns for NMR and ESR spectra are reviewed. It is shown that these techniques can be applied to both I3C and proton NMR of molecules as well as to predict the hyperfine pattern in the ESR spectra of complex polyatomic radicals.

High resolution of NMR spectroscopic data of biosamples are a rich source of information on the metabolic response to physiological variation or pathological events. There are many advantages of NMR techniques such as the sample preparation is fast, simple and non-invasive. Statistical analysis of NMR spectra usually focuses on differential expression of large resonance intensity corresponding ...