Universidade Federal de Viçosa

About: Universidade Federal de Viçosa is a education organization based out in Viçosa, Brazil. It is known for research contribution in the topics: Population & Biology. The organization has 16012 authors who have published 26711 publications receiving 353416 citations.

Layered double hydroxides: nanomaterials for applications in agriculture

Abstract: The current research aims to introduce Layered Double Hydroxides (LDH) as nanomaterials to be used in agriculture, with particular reference to its use as storage and slow release matrix of nutrients and agrochemicals for plant growing. Structural characteristics, main properties, synthesis methods and characterization of LDH were covered in this study. Moreover, some literature data have been reported to demonstrate their potential for storage and slow release of nitrate, phosphate, agrochemicals, besides as being used as adsorbent for the wastewater treatment. This research aims to expand, in near future, the investigation field on these materials, with application in agriculture, increasing the interface between chemistry and agronomy.

Flaxseed and Human Health: Reviewing Benefits and Adverse Effects

Abstract: Consumption of flaxseed has been increased due to its possible functional properties in health. However, its chronic consumption may offer risks considering the effects of lignans in men and in pregnant women, as well as the existence of other phytochemicals and toxic factors with adverse health effects in the seed. The present review focuses on the growing body of evidence on the potential health benefits of flaxseed in humans, with supporting evidence from human and animal studies. It also raises questions that provide input for future research on the effects of flaxseed ingestion in terms of nutrient bioavailability and human fertility.

Effect of iron precursor on the Fenton-like activity of Fe2O3/mesoporous silica catalysts prepared under mild conditions

Abstract: Fe2O3/mesoporous silica catalysts were prepared by adding Fe2+ or Fe3+ ions, as an iron precursor, during the synthesis of silica gel. Low angle XRD data showed that both iron precursors affected the hexagonal ordered arrays of silica, which were more perturbed by Fe2+ than by Fe3+ ions, as confirmed by TEM images. Based on the Mossbauer spectroscopy, XPS, EPR and NH3-TPD data was possible to identify the iron species supported on the silica matrix are constituted of hematite and maghemite. The iron precursor strongly changed the specific area of the materials from 1406 m2 g−1, in pure silica sample, to 1165 and 799 m2 g−1 for the Fe3-MS and Fe2-MS samples, respectively, but the pore size distribution was maintained in the range of 15–40 A in both samples. These Fe-containing silica nanoparticles showed good catalytic activity to degrade methylene blue in aqueous medium. However, the Fe3-MS sample was more active than the Fe2-MS sample because the iron in the first is more exposed, which facilitated the accessibility to the active Fenton-like sites. These synthesized samples showed to be more stable against the Fe leaching than samples prepared by simple impregnation of hematite on the silica surface. This was because the strong interaction of iron and silica matrix was achieved by adding iron in the course of the synthesis of silica gel.