Search results for "Chemical study"
showing 7 items of 7 documents
COMPOSITION OF THE ESSENTIAL OILS IN CALENDULA SUFFRUTICOSA (ASTERACEAE) FROM SICILY
2016
The genus Calendula L. (Calenduleae Cass., Asteraceae) includes several species having medicinal properties. Pharmacological studies reveal, for instance, that C. officinalis L. exhibits antibacterial, antiviral, antinflammatory, antitumor and antioxidant properties; C. arvensis L. has antibacterial, antinflammatory, antimutagenic and haemolytic activities; C. suffruticosa Vahl has antimicrobial activity, especially against pathogenic microorganisms as Pseudomonas syringae Van Hall, Pseudomonas fluorescens (Flügge) Migula, Xanthomonas campestris (Pammel) Dowson and Agrobacterium tumefaciens Smith & Townsend. Nevertheless, despite a long tradition of use of the above species, and others,…
Adenoid Cystic Carcinoma of Salivary Gland: An Immunohistochemical Study
2019
The hydrophilie of the larval test of Ascidiae: functional role played by test cells
2012
Ascidian swimming larvae are entirely surrounded by a hyaline extracellular coat, called as tunic or test, on which numerous test cells adhere. The functional role played by test cells in larvae of various ascidian species consists in depositing submicroscopic structures known as ornaments and/or substances of proteoglycan nature in the larval test surface. The deposition of ornaments would render the larval test hydrophilic and thus allow the larvae to swim being immersed in sea water. Ultrastructural investigations reported in literature on larvae of Cionidae and Ascididae families have not evidenced the presence of ornaments in the swimming larval test. For these Ascididae families it ha…
Amorphous to Crystalline Transition in Anodic Oxide on Ti and Ti-Si alloys: A Photoelectrochemical Study.
2012
Elaboration et caractérisation mécanique et physico-chimique des revêtements déposés sur des substrats en laiton par les techniques de projection the…
2019
Brass alloys are used in many applications, especially in the sanitary industrial application. In this field, the brass is coated with an electroplated chromium layer. However, the electroplating technique is achieved by means of solutions in which the chromium is in the six oxidation state. At this degree of oxidation, chromium is toxic and has the reputation of being carcinogenic. In this context, the main objective of this work is to develop functional coatings on brass substrates using new techniques namely thermal and pneumatic spraying techniques. The mechanical and physical-chemical properties are studied in order to evaluate the performances of these coatings and the potency of thei…
Tailoring of the solid state properties of Al-Nb mixed oxides: A photoelectrochemical study
2013
Al-Nb containing mixed oxides were grown by anodizing sputter-deposited Al-Nb alloys of different compositions. A photoelectrochemical investigation was carried out in order to estimate the band gap, flat band potential, and conductivity type of these oxides as a function of their composition. The dependence of the band gap on the composition of mixed sp-d metal oxides has been rationalized by using a semiempirical correlation between the difference of electronegativity and band gap of oxides proposed in the literature some years ago and recently tested for regular d-d metal mixed oxides. The band gap increase observed as a function of Al content into the oxides seems mainly depending on th…
Systematic conformational search analysis of the SRR and RRR epimers of 7-hydroxymatairesinol
2010
An extensive and systematic conformational search was performed on the two epimers of the natural lignan 7-hydroxymatairesinol (HMR), by means of a home-made Systematic Conformational Search Analysis (SCSA) code, designed to select more and more stable conformers through sequential geometry optimization of trial structures at increasing levels of calculation theory. In the present case, the starting molecular structures were selected by the semi-empirical AM1 method and filtered – i.e. decreased in number by choosing the more stable species – on the basis of their energy calculated by the HF method and the 6-31G(d) basis set. The geometries obtained were further refined by performing densit…