The ongoing pursuit of enhanced efficiency and sustainability in power transformer cooling systems has spurred extensive research into the properties and performance of insulating fluids. This review explores the evolution of transformer cooling technologies, focusing on traditional mineral oils and the emerging roles of alternative fluids, such as natural and synthetic esters, and nanofluids. Mineral oils, though widely used, degrade over time, leading to a reduction in breakdown voltage (BDV) from 46 kV to 30 kV, exhibiting low fire resistance.
View Article and Find Full Text PDFObjective: To evaluate the enamel bonding ability and orthodontic adhesive resin degree of conversion using the experimental bracket design. . Thirteen bovine teeth were used in the study.
View Article and Find Full Text PDFThe Neotropical genus Marma Simon, 1902 is revised. With exception of the holotype of M. femella (Caporiacco, 1955), which was redescribed in previous work, all the other species of the genus were revised based on their types.
View Article and Find Full Text PDFSeven new species of Amphidraus Simon, 1900 are described from Brazil: A. araripe sp. nov.
View Article and Find Full Text PDFInadequate solid waste management leads to contamination of the soil and surface and underground water; the emergence of antibiotic-resistant superbacteria due to the inadequate disposal of medicines in toilets or in household rubbish; and the emission of persistent organic pollutants, such as flame retardants, present in some electrical/electronic equipment. In Brazil, the principles that underpin the National Solid Waste Policy (PNRS) are consistent with those used by developed countries, namely, the polluter-payer and protector-receiver; cooperation among the different spheres of government, the business sector, and other societal segments; and the shared product life-cycle responsibility (Brasil, 2010a; Novi et al., 2013; Santos et al.
View Article and Find Full Text PDFTwo new species of Neonella Gertsch, 1936 from Brazil are described: N. gyrinus sp. nov.
View Article and Find Full Text PDFObjectives: The antiplaque and antigingivitis effects of a gel containing 10% Punica granatum Linn extract were evaluated using a 21-day partial-mouth experimental model of gingivitis.
Methods: 23 volunteers participated in this cross-over, double-blind study, carried out in 2 phases of 21 days each. For each period of the experiment, an acrylic toothshield was made for each volunteer to carry the test or placebo gel as well as to avoid brushing of the 4 experimental teeth (posterior teeth in the lower left quadrant).