Editorial

Wishing that all people may pass well in this worrying period of covid-19, the Editor is pleased to announce the third issue of this year containing interesting topics for the readers. This issue is opened with the description of monoclinic or triclinic forms of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes successfully synthesized with a ligand resulting from the condensation reaction of isatin and glutamic acid. Physico-chemical properties of complexes were extensively investigated by elemental analysis, XRF, XRD, FTIR, TG–DSC and TG–FTIR methods and magnetic measurements. It is well known that non-edible fats are a common renewable feedstock for the biofuels production to avoid partially the use of edible feeds and fossil fuels. Thus, the use of waste rendering fat to produce pyrolyzed and hydrogenated oils was described. The feedstock was hydrolyzed producing free fatty acids and glycerol plus residues. The free fatty acids were pyrolyzed with and without metal sulfides metal supported catalyst or hydrotreated separately. In the sequence, a spectrophotometric method is described to determine paracetamol concentration in 7 pharmaceutical formulations, using 1,3 dinitrobenzene or 2,4 dinitrophenyl hydrazine as coupling agent. This easy procedure is based on the reaction of paracetamol acid hydrolysis to p-aminophenol that reacts with nitrite to form diazonium ion, which is coupled with coupling agent to produce azo dyes easily analyzable. Lately, it has been observed that the cities’ rapid expansion led the domestic and industrial hydraulic drainage networks to become gradually more complicated. Dealing with this subject, the following paper contributes to the evaluation of the major and minor head losses in a hydraulic flow circuit and compares the simulated results with the Moody's diagram application, having observed an extremely low absolute deviation. This issue is closed with an interesting article in education in chemistry section on how to distinguish between databases that are efficient and objective for literature searches and revises important points of the database for chemists. It concludes that substance and citation data bases that covers almost all areas of chemistry, have become an invaluable tool in bibliometric analysis.

The Editor and his team wish to express their sincere thanks to authors for their great contributions, and reviewers for their outstanding manuscripts evaluation.

Assis Vicente Benedetti

Editor-in-Chief of EQJ