Study of polyphenols of the leaves of an ibero moroccan endemic, Thymelaea lythroides.

Study of polyphenols of the leaves of an ibero moroccan endemic, Thymelaea lythroides. Thymelaea lythroides (Thymelaeacees) is an endemic of the region of the Gharb (forest of Mamora). It is part of the panoply of the medicinal and aromatic plants of Morocco. Because of the lack of phytochemical informations on the species, some previous studies had for object a research of the antifungal activity of its extracts and a phytochemical screening. This last permitted to put in evidence the wealth of the plant in different secondary compounds. Thus, the present work intends to study the polyphenols of the leaves of Thymelaea lythroides and specially the flavonics aglycones and the anthocyanidins. The survey demonstrated the existence of different molecules belonging to the class of the flavonols, whose identification revealed the kaempferol and quercetine. In addition to two acidic phenols, identified as the cofeique acid and the genticique acidic and two anthocyanidins, the delphinidine and the cyanidine

Modifications induced by sweeping and observed in quartz crystals according to their α3500-value

In order to check what sweeping can induce in quartz material, two particular blocks have been studied. These crystals were chosen according to their α3500 infrared value, and so classified as standard quartz or HQ quartz. The different techniques, infrared spectroscopy, ICP chemical analysis, X-ray topography and etching have been used on the same samples before and after sweeping. The chemical analysis results show an effective migration of alkalis. This migration is different from a sample to the other but it remains sometimes very weak in both cases. The decrease of the number of the etch-pits and the length of the etch-channels has been verified in the swept part of the crystal comparably to the unswept part of the same crystal ; the initial quality of the material appears to be an important parameter. X-ray topography shows that there is no modification by sweeping in the partition of the dislocations within both the crystals. Infrared spectroscopy reveals that the homogeneity of the crystals can be modified by sweeping. The measurements lead to some unexpected results which indicate that the sweeping cannot be considered as a routine process

IR and N-IR spectrometry characterizations of LGS crystal and family

Middle and near infrared (MIR/NIR) spectrometry has been used to characterize series of samples of LGx family and GaPO$_{4}$. Since OH impurities influence the material properties, their spectroscopy is investigated in detail. The [190–3200 nm] region is measured in transmission. Furthermore, the study of spectra made at Nitrogen liquid temperature is used to follow the modification in the signature of some defects present in the lattice and induced by treatments as $\gamma$ irradiation or annealing. At least, we show that these “new” materials contain less OH-groups than quartz crystal