Analysis of biological fluids by high-field nuclear magnetic resonance spectroscopy

The application of high-field Fourier transform nuclear magnetic resonance (NMR) spectroscopy to the analysis of biological fluids such as urine, plasma and bile is described. Applications include areas such as clinical chemistry, experimental and clinical toxicology and drug metabolism studies. In the case of proton NMR some means of attenuating or eliminating the interference due to water protons is required and suitable strategies for achieving this are discussed. The use of 2-dimensional NMR or solid-phase extraction/chromatography to enable the identification of unknowns is discussed and the potential usefulness of ¹⁹F NMR for studying the metabolism of fluorinated xenobiotics is highlighted.     

Rubber elasticity in relation to polyester networks

The equation of rubber elasticity has been applied to the dynamic shear modulus of styreneunsaturated polyester networks. Due to the non-ideal nature of the networks, the apparent front factor approached the theoretical value of 0.5 only when the crosslink density was low. At higher crosslink densities, it has been found that either the non-Gaussian theory of Smith or the steric interaction approach of Blanchard and Wooton satisfactorily describes the results.     

Benetzbarkeit von Wollfasern

Ohne Zusammenfassung     

Long range substituent-induced chemical shifts in the 13C NMR spectra of N-benzylidenebenzylamines

Carbon-13 chemical shifts for N-benzylidenebenzylamines are affected by substituents up to eleven bonds away from the substituent group. The data correlate well with Hammett constants.     

Die Anwendung der Stufen-Regeln für niedrige Grenzflächen spanung auf Gemische binärer Kohlenwasser stoffe

Ohne Zusammenfassung     

The tautomerism of heteroaromatic compounds with 5-membered rings—XI 4-Hydroxyisoxazoles-4-isoxazolinones

Four 4-hydroxyisoxazoles together with model compounds have been investigated by UV, IR and NMR spectroscopy and by pK_a measurements, 4-Hydroxyisoxazoles exist predominantly in the hydroxy-form in a wide range of media.     

A note on the magnetic susceptibility of hydrogen and its isotopomers

A wavefunction used in an earlier calculation of the nuclear shielding of the hydrogen molecule has been tested by comparing the calculated magnetic susceptibility against that of Kolos and Wolniewicz. Good agreement is obtained. The procedure of Herman and Short for averaging over the nuclear motion has also been tested by comparing the predicted susceptibilities of H₂, Hd and D₂ with those obtained from averages of the Rydberg-Klein-Rees potential curves by Jain and Sahni. Again, good agreement is found.For the first time calculated values have been obtained for the susceptibilities of the isoropomers of hydrogen which contain tritium. It is predicted that accurate susceptibility measurements should not only be able to distinguish between all the various isotopomers but should also detect the temperature dependence of the susceptibility of any one isotopomer.