Influência das formas de arraçoamento na performance de suínos.

O presente estudo foi conduzido para avaliar a influência de várias formas de fornecimento de ração para suínos em crescimento e acabamento

Control by atomic layer deposition over the chemical composition of nickel cobalt oxide for the oxygen evolution reaction

Anion exchange membrane water electrolysis (AEMWE) is a promising technology for renewable electricity-driven water splitting toward hydrogen production. However, application of AEMWE at industrial scale requires the development of oxygen evolution reaction (OER) electrocatalysts showing long-term stability under mild alkaline conditions. Among these, nickel cobalt oxide thin films are considered promising candidates. The ideal chemical composition of these oxides remains debatable, with recent literature indicating that rock-salt NiCoO2 may exhibit similar OER activity as the traditional spinel NiCo2O4. In this work, we present the development of a plasma-enhanced atomic layer deposition (ALD) process of nickel cobalt oxide thin films (∼20 nm) with focus on the role of their chemical composition and crystal structure on the OER activity. The film composition is tuned using a supercycle approach built upon CoOx cycles with CoCp2 as a precursor and O2 plasma as a co-reactant and NiOx cycles with Ni(MeCp)2 as a precursor and O2 plasma as a co-reactant. The films exhibit a change in the crystallographic phase from the rock-salt to spinel structure for increasing cobalt at. %. This change is accompanied by an increase in the Ni3+-to-Ni2+ ratio. Interestingly, an increase in electrical conductivity is observed for mixed oxides, with an optimum of (2.4 ± 0.2) × 102 S/cm at 64 at. % Co, outperforming both NiO and Co3O4 by several orders of magnitude. An optimal electrocatalytic performance is observed for 80 at. % Co films. Cyclic voltammetry measurements simultaneously show a strong dependence of the OER-catalytic performance on the electrical conductivity. The present study highlights the merit of ALD in controlling the nickel cobalt oxide chemical composition and crystal structure to gain insight into its electrocatalytic performance. Moreover, these results suggest that it is important to disentangle conductivity effects from the electrocatalytic activity in future work

Estudos preliminares do uso de oxitetraciclina, cobre e mecadox em rações de suínos.

Duzentos leitões desmamados, com peso médio inicial 9,13 kg, foram divididos em quatro grupos e submetidos aos seguintes tratamentos: T 1 - ração baseada em milho e farelo de soja + 40,0 p.p.m, de oxitetraciclina; T2 - mesma ração de T1 + 40,0 p.p.m de oxitetraciclina + 250 p.p.m. de Cu (na, forma de sulfato); T3 - mesma ração de T1 + 250 p.p.m. de Cu e T4 - mesma ração de T 1 + 200 p.p.m. de Mecadox

Estudo comparativo da performance de suínos puros e mestiços. I - Performance de crescimento (nota prévia).

Foram comparados os resultados da performance de crescimento os caracteres: ganho de peso, consumo de ração e conversão alimentar, de suínos dos seguintes grupos genéticos: - Duroc (DU), Landrace (LA) e Large White (LW) puros, e meios sangues Duroc x Hampshire (DU x HA) e Duroc x Large White (DU x LW)

Maps of solar wind plasma precipitation onto Mercury's surface: a geographical perspective

Mercury is the closest planet to the Sun, possesses a weak intrinsic magnetic field and has only a very tenuous atmosphere (exosphere). These three conditions result in a direct coupling between the plasma emitted from the Sun (namely the solar wind) and Mercury’s surface. The planet’s magnetic field leads to a non-trivial pattern of plasma precipitation onto the surface, that is expected to contribute to the alteration of the regolith over geological time scales. The goal of this work is to study the solar wind plasma precipitation onto the surface of Mercury from a geographical perspective, as opposed to the local-time-of-day approach of previous precipitation modeling studies. We employ solar wind precipitation maps for protons and electrons from two fully-kinetic numerical simulations of Mercury’s plasma environment. These maps are then integrated over two full Mercury orbits (176 Earth days). We found that the plasma precipitation pattern at the surface is most strongly affected by the upstream solar wind conditions, particularly by the interplanetary magnetic field direction, and less by Mercury’s 3:2 spin-orbit resonance. We also found that Mercury’s magnetic field is able to shield the surface from roughly 90% of the incoming solar wind flux. At the surface, protons have a broad energy distribution from below 500 eV to more than 1.5 keV; while electrons are mostly found in the range 0.1-10 keV. These results will help to better constrain space weathering and exosphere source processes at Mercury, as well as to interpret observations by the ongoing ESA/JAXA BepiColombo mission