Métodos para determinar taninos em sorgo, avaliando-se o desempenho de aves e a digestibilidade in vitro da matéria seca.

Com o objetivo de comparar metodos para determinar a presenca de taninos em sorgo (Sorghum bicolor (L.) Moench), foi conduzido um experimento com aves e realizada a analise da digestibilidade "in vitro" da materia seca. Foram avaliados os metodos Azul da Prussia, Vanilina/HCI e Proantocianidina, e na preparacao das racoes, foram utilizados dez diferentes hibridos de sorgo e uma variedade de milho. A presenca de compostos fenolicos determinada pelo metodo Azul da Prussia apresentou maior correlacao com o ganho de peso das aves e a digestibilidade "in vitro" da materia seca

Characterisation of demoulding parameters in micro-injection moulding

YesCondition monitoring of micro injection moulding is an effective way of understanding the processing effects of variable parameter settings. This paper reports an experimental study that investigates the characteristics of the demoulding behaviour in micro injection moulding (A mu-IM) with a focus on the process factors that affect parts' quality. Using a Cyclic Olefin Copolyme (COC) microfluidics demonstrator, the demoulding performance was studied as a function of four process parameters (melt temperature, mould temperature, holding pressure and injection speed), employing the design of experiment approach. The results provide empirical evidences on the effect that processing parameters have on demoulding conditions in A mu-IM, and identifies combinations of parameters that can be used to achieve the optimal processing conditions in regards to demoulding behaviour of micro parts. It was concluded that there was a direct correlation between the applied pressure during part filling, holding phases and the demoulding characteristic factors of the A mu-IM cycle such as ejection force, integral and time

Test results of the front-end system for the Silicon Drift Detectors of ALICE

The front-end system of the Silicon Drift Detectors (SDDs) of the ALICE experiment is made of two ASICs. The first chip performs the preamplification, temporary analogue storage and analogue-to-digital conversion of the detector signals. The second chip is a digital buffer that allows for a significant reduction of the connection from the front-end module to the outside world. In this paper, the results achieved on the first complete prototype of the front-end system for the SDDs of ALICE are presented

Performance evaluation of polymer-filled metal fused filament fabrication tooling for profile extrusion

The application of additive manufacturing (AM) for tooling in the mould and die industry brings a disruptive potential in process performance, design flexibility and product enhancements. Maturing of existing AM technologies and emerging technologies such as metal-fused filament fabrication (metal FFF) can further support the applicability of AM tooling in polymer profile extrusion. This study provides a complete characterization of metal FFF 17–4 PH stainless-steel die inserts and evaluates their applicability in a polymer extrusion process chain. The presented experimental assessment pivots on the metrological characterization of the produced inserts and the impact of the insert characteristics on the final extrudates’ product. Considering a conventionally manufactured benchmark insert, produced via subtractive methods (CNC machining and electrical discharge machining), comparable results for AM tools in terms of extrudates’ quality and process repeatability are presented. It was found that despite significant higher average surface parameters for AM insert tools (Sa = 2–9 μm vs. Sa = 0.3–0.9 μm for dies manufactured by machining), a much smaller difference was observed in the resulting quality of polymer extrudates’ product. The roughness generation effect of polymer profile extrusion based on the different dies’ internal surface roughness topography and the effect on extrudates product was evaluated. Three-dimensional average roughness Sa on acrylonitrile butadiene styrene extrudate surfaces obtained from conventionally machined dies was in the range of 0.3 μm. For extrudates obtained from additively manufactured dies, their Sa was in the rage of 0.5 μm (despite the much higher surface roughness of FFF dies compared to machined dies). The results confirm that with suitable extrudates’ product requirement, it is feasible to apply metal FFF as the selected manufacturing method for tooling in polymer profile extrusion