Efeito da altura do resíduo sobre a produção e a estrutura de sorgo forrageiro.

O cultivo de sorgo forrageiro (Sorghum bicolor (L.) Moench.) tem crescido na região Noroeste do Rio Grande do Sul nos últimos anos. Os produtores rurais estão sendo orientados a manejar o sorgo forrageiro em pastejo rotacionado, respeitando uma altura de entrada dos animais acima de 70 cm e altura de saída (resíduo) em torno de apenas 5 cm.bitstream/item/63868/1/BP31.pd

The effect of crack insertion for FDM printed PLA materials on Mode I and Mode II fracture toughness

The paper presents mode I and II fracture toughness results for polylactic acid material obtained via fused deposition modeling. The tests were performed using Single Edge Notch Bend specimens loaded in four point bending: symmetric for mode I, asymmetric for mode II, respectively. The notch was inserted by 3D printing, and by milling, respectively. Fracture toughness values measured for the specimens with 3D printed notch resulted to be higher than those obtained by milling. The effect of notch insertion is more evident in mode I while it is less important for mode II

Constraints on the Progenitor of SN 2016gkg From Its Shock-Cooling Light Curve

SN 2016gkg is a nearby Type IIb supernova discovered shortly after explosion. Like several other Type IIb events with early-time data, SN 2016gkg displays a double-peaked light curve, with the first peak associated with the cooling of a low-mass extended progenitor envelope. We present unprecedented intranight-cadence multi-band photometric coverage of the first light-curve peak of SN 2016gkg obtained from the Las Cumbres Observatory Global Telescope network, the Asteroid Terrestrial-impact Last Alert System, the Swift satellite and various amateur-operated telescopes. Fitting these data to analytical shock-cooling models gives a progenitor radius of ~25-140 solar radii with ~2-30 x 10^-2 solar masses of material in the extended envelope (depending on the model and the assumed host-galaxy extinction). Our radius estimates are broadly consistent with values derived independently (in other works) from HST imaging of the progenitor star. However, the shock-cooling model radii are on the lower end of the values indicated by pre-explosion imaging. Hydrodynamical simulations could refine the progenitor parameters deduced from the shock-cooling emission and test the analytical models.Comment: Accepted by ApJ

Design and Analysis of Energy Absorbent Bioinspired Lattice Structures

The increasing demand for energy absorbent structures, paired with the need for more efficient use of materials in a wide range of engineering fields, has led to an extensive range of designs in the porous forms of sandwiches, honeycomb, and foams. To achieve an even better performance, an ingenious solution is to learn how biological structures adjust their configurations to absorb energy without catastrophic failure. In this study, we have attempted to blend the shape freedom, offered by additive manufacturing techniques, with the biomimetic approach, to propose new lattice structures for energy absorbent applications. To this aim we have combined multiple bio-inspirational sources for the design of optimized configurations under compressive loads. Periodic lattice structures are fabricated based on the designed unit cell geometries and studied using experimental and computational strategies. The individual effect of each bio-inspired feature has been evaluated on the energy absorbance performance of the designed structure. Based on the design parameters of the lattices, a tuning between the strength and energy absorption could be obtained, paving the way for transition within a wide range of real-life applicative scenarios

Análise do comportamento de matrizes suínas lactantes com o uso de enriquecimento ambiental na maternidade.

Projeto/Plano de Ação: 02.09.07.007

Local strain energy density for the fracture assessment of polyurethane specimens weakened by notches of different shape

Recent studies on local stress fields in proximity of crack and notch tips have shown that Strain Energy Density (SED), averaged in a circular control volume surrounding the point of stress singularities, represents a reliable engineering approach for assessing the brittle fracture of several brittle materials. It is worthy of notice that the application of SED criterion and the reliability of its results are strictly related to the proper determination of fracture parameters, i.e. the critical value of deformation energy Wc and the radius Rc of the control volume. This work presents an experimental methodology for their determination by means of notched specimens for different polyurethane densities, ranging from 100 to 651 kg/m3. Then, once obtained these critical parameters, the failure load in different types of notches and cracked specimens under mode I have been predicted. Moreover, for cracked specimens under mixed mode and mode II, the authors propose a personal approach that confirms PUR foams can be treated as brittle material

Rede Leite: programa em rede de pesquisa-desenvolvimento em sistemas de produção com pecuária e leite no noroeste do Rio Grande do Sul.

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