Series of polynuclear diorganotin(IV) complexes with di-halogenbenzohydroxamate ligands (substituents=2,4-Cl(2), 2,4-F(2), 3,4-F(2), 2,5-F(2), 2,6-F(2)), formulated as the polymeric [R(2)SnL](n)a (1:1) and the tetranuclear [R(4)Sn(2)(HL)(2)(L)](2)b (2:3) (HL=arylhydroxamate), were prepared and characterized by FT-IR, (1)H, (13)C, (119)Sn NMR spectroscopies, elemental analyses and melting point ...

Several petroleum pitches have been prepared by thermal treatment of various petroleum-derived residues such as clarified oil, aromatic extract and pyrolysis tars. These pitches were characterized physico-chemically (softening point, coking value, QI, & TI) and instrumentally (NMR) and compared. Attempts have been made to correlate physicochemical properties of petroleum residues and pitches wi...

With SGF Profiling™ we introduce an NMR-based screening method for the quality control of fruit juices. This method has been developed in a joint effort by Bruker BioSpin GmbH and SGF International e.V. The system is fully automated with respect to sample transfer, measurement, data analysis and reporting and is set up on an Avance 400 MHz flow-injection NMR spectrometer. For each fruit juice a...

Cross-Polarisation-magic-angle-spinning (CPMAS) with high-power proton decoupling [Schaefer, 1976] has been widely applied to obtain high resolution NMR spectra of dilute spin1/2 in solids. This method averages out all anisotropic NMR interactions which transform as second-rank tensors, such as chemical shift anisotropical interactions. However, the principal elements of chemical shift anisotro...

1. Introduction Multidimensional NMR methods have become an important tool in the 1970s. In the past years a new set of experiments has developed whose postprocessing is based on a multidimensional inverse Laplace transformation rather than a Fourier transformation which provides the capabilities to find correlations between various parameters such as diffusion coefficients D and NMR relaxation...

Density functional theory calculations were applied to investigate 13C Chemical Shielding (CS) tensors in cryptolepine (1) and its sulfur (2) and oxygen (3) isosteres. The results showed that the CS of carbon nuclei in these compounds may be divided into three types. First, carbons type α,are those directly bonded to X (X= NH, S, O) and σ 33 shielding component of these carbons are deshield...