Search results for "MR measurement"
showing 2 items of 2 documents
The effect of some amines and alcohols on the organized structure of [bmim][BF4] investigated by 1H NMR spectroscopy
2008
The effect exerted by some amines and alcohols on the 1H NMR spectra of 1-butyl-3- methylimidazolium tetrafluoroborate [bmim][BF4] has been studied. This ionic liquid, which is one of the most widely used, is characterized by a high structural order degree, as a consequence of the symmetry and the coordination ability of the anion. In order to have information about the dependence of the detected effects on the alcohol or amine structure, some different primary, secondary and tertiary amines and alcohols have been considered. Furthermore, in the case of amines, their basicity has been also taken into account. Both amines and alcohols induce variation in chemical shifts values and signal mul…
Study of optical absorbance and MR relaxation of Fricke xylenol orange gel dosimeters
2017
Abstract Studies on the optical absorbance spectra of Fricke xylenol orange gel dosimeters were performed, in the wavelength range from 300 nm to 800 nm, in order to highlight some particular characteristics that can affect the achievable precision. The spectra are different mainly due to the different types of xylenol orange that was used and to a lower extent due to the different gelling agents (agarose or gelatine). The characteristic of variation of absorbance spectra versus dose, however, are similar in the various cases and can explain some peculiarities, as apparent effects of dose threshold. Changes of spectral shapes appear over the time after irradiation. Magnetic resonance measur…