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A poly-epsilon-caprolactone based biofilm carrier for nitrate removal from water

Nitrate removal from water has been accomplished by heterotrophic biofilms using organic carbon as a source of reducing power. To overcome the natural limitation in organic carbon in water, a poly-epsilon-caprolactone based biofilm carrier that serves simultaneously as a biofilm carrier and as a source of organic carbon was developed and tested in the present work. The feasibility of the new biofilm carrier for...

Numerical and experimental investigations of three-dimensional container fillin...

This work employs numerical and experimental approaches to investigate three-dimensional container filling with Newtonian viscous fluids. For this purpose, a computer code developed for simulating three-dimensional free surface flows has been used. The CFD Freeflow3D code was specifically designed to deal with unsteady three-dimensional flows possessing multiple moving free surfaces. An experimental apparatus t...

Piezoelectric co-axial filaments produced by co-extrusion of poly(vinylidene fl...

Documento submetido para revisão pelos pares. A publicar em "Journal of applied polymer science". ISSN 1097-4628. Article first published online: 3 APR 2014 : http://onlinelibrary.wiley.com/doi/10.1002/app.40710/abstract. DOI 10.1002/app.40710. ; The development of new thermoplastic polymer-based piezoelectric sensors with filament geometry is described. These filaments are appropriate for integration into tex...

Folheto do Projeto Rose4Pack

Three layer polymer piezoelectric filaments produced by extrusion

Poly(vinylidene fluoride) (PVDF) is extensively studied due to its piezo-, pyro- and ferroelectric properties. These properties enable the use of this polymer in a number of applications either as sensor or actuator. PVDF is a semi-crystalline polymer and can crystallize in four different crystalline phases, called α, β, γ and δ. The β-phase presents the most interesting electroactive activity. These properties...

Properties and processing by extrusion of electrically conductive multilayer fi...

This work describes the production and characterization of three-layer piezoelectric filaments using two different electrically conductive polymers. The filaments were produced in a filament extrusion line, equipped with a coextrusion die that enabled a coaxial arrangement for a three-layer filament. For the inner and outer layers two different electrically conductive compounds were used, and the middle layer w...

Coextrusion of multilayer piezoelectric tape

Materials with piezoelectric properties are defined as materials that produce an electrical potential when subjected to mechanical stress (sensor function) or, in the opposite sense, produce mechanical work when subjected to an electrical field (actuator function). Poly(vinylidene fluoride), PVDF, is a polymer with a high piezoelectric coefficient, and thus is often used in the above mentioned applications. Th...

Extrusion of poly(vinylidene fluoride) recycled filaments : effect of the proce...

This study analyses the possibility of reprocessing used poly(vinylidene fluoride), PVDF, maintaining the main properties critical for its use in piezoelectric sensor/actuator applications. The influence of multiple reprocessing cycles of PVDF on crystallinity and ß-phase content fundamental for its electroactive behaviour, was studied. Nine reprocessing cycles were completed and it was found that the material ...

Design of complex profile extrusion dies through numerical modeling

The achievement of a balanced flow is one of the major tasks encompassed in the design of profile extrusion dies [1]. For this purpose numerical modeling codes may be a very useful aid. The research team involved in this work has been working during the last decade on the development of numerical tools to aid the conception of extrusion dies [1,2]. The design code developed so far carries out the automatic sear...

Prototype and methodology for the characterization of the polymer-calibrator in...

The extrusion of technical thermoplastics profiles generally uses a dry calibration/cooling system, composed by one or several calibrators in series. One of the major difficulties to be faced when modelling this important stage is an adequate prescription of the heat transfer coefficient, hinterface, between the plastic profile surface and the cooling medium, which must include the effect of the interface conta...