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- Design of Pyrolysis System to Convert Waste Plastic to FuelsPublication . Oliveira, Nelson S.; Pardo, Michael; Capela, Carlos; Gaspar, Marcelo; Vasco, Joel; Heleno, LizeteThe conventional recycling technology to process waste plastic, mechanical recycling, is not suitable to recycle waste thermoplastic with high content of contamination. Pyrolysis is a promising technology since it can convert into valuable products, such as fuels and monomers. This study focused on the design of the pyrolysis equipment for waste plastic based on polyolefins. The feeder of waste plastic is a worm screw conveyor that will be in a pre-heating system. The batch reactor has support for catalyzer and can operate between 300 up to 600 ºC with attached induction system for heating. The output flows into condenser in series to separate two liquid phases and gases, depending on its boiling point. The 3D model was done with SolidWorks, control system modelled in CADe SIMU and particle simulation with FloXpress.
- Direct Digital Manufacturing: A Challenge to the Artistic Glass ProductionPublication . Felismina, R.; Silva, M.; Mateus, A.; Malça, C.Currently the high hand-labor costs, long production times, lack of automation and high energy consumption associated with the high temperatures required to produce pieces of glass, are identified as the main inhibitors of growth and economic development of the decorative and utility glass industrial sector. Current production processes impose limitations on the complexity of the geometry and shape of the glass pieces to be produced, which in turn greatly restricts the creativity of designers and consequently, the characteristics of differentiation and innovation presented by new products on the market.
- Chapter 8: Structure Development in Electrospun FibresPublication . Mitchell, Geoffrey R.; Mohan, Saeed D.; Davis, Fred J.; Ahn, Kyung-Hwa; Al-Azab, Mohamed; El Hadi, Ahmed; Elliott, Delyth; Kariduraganavar, Mahadevappa Y.; Nagarajan, Anitha; Nazhipkyzy, Meruyert; Geoffrey R MitchellElectrospinning is a process which transforms polymer solutions in to solid fibres in ∼25 ms. In the case of an amorphous polymer, the resultant molecular organisation may not be so different from that of the solution. However, polymers are rich in different types of ordering processes and these may be encountered during electrospinning. In many areas of polymer processing, the processing procedures can have a significant impact on the structure and hence properties of the final product as the selection of the chemical configuration
- Future Perspectives on ElectrospinningPublication . Mitchell, Geoffrey R.; Sperrin, MalcolmAlthough the origins of electrospinning date back over 100 years, it is intense activity in the last 21 years which has led to considerable improvements in our knowledge of electrospinning and the broad-ranging opportunities for commercial application. The recent development of melt electrospinning provides a new additive manufacturing tool, providing routes to structures from nanometres to millimetres. Here, we consider where this rollercoaster of a topic is heading and its future prospects.
- Biofabrication Strategies for Tissue EngineeringPublication . Bártolo, Paulo Jorge; Domingos, Marco; Patrício, Tatiana; Cometa, Stefania; Mironov, Vladimir; Bártolo, Paulo JorgeThe success of Tissue Engineering (TE) strongly relies on the capability of designing biomimetic scaffolds closely resembling the host tissue environment. Due to the functional multitude of the native tissues, the considerations are complex and include chemical, morphological, mechanical and biological factors and their mutability with time. Nonetheless, to trigger and/or assist the “natural healing mechanism’’ of the human body it seems essential to provide an appropriate biomechanical environment and biomolecular signalling to the cells. Novel biomanufacturing processes are increasingly being recognized as ideal techniques to produce 3D biodegradable structures with optimal pore size and spatial distribution, providing an adequate mechanical support for tissue regeneration while shaping in-growing tissues. In this chapter, we discuss in detail the most recent advances in the field of biofabrication, providing and updated overview of processes and materials employed in the production of tissue engineering constructs. Bioprinting or ‘’scaffold-less’’ strategies are also presented in this work. They are based on the precise deposition of high-density tissue spheroids or cell aggregates being advantageous alternatives to the current scaffold-based tissue engineering approach.
- Electrospinning for Medical ApplicationsPublication . Song, Wenhui; Mitchell, Geoffrey R.; Burugapalli, KrishnaThere is a natural connection between a variety of electrospun fibres and biomedical applications. The most commonly quoted application of electrospun fibres is their use as scaffolds in tissue engineering for regenerative medicine. There are also many other applications, which include drug delivery systems, membrane systems and analytical functionality. This chapter identifies the key challenges in each of these topics, as well as the particular role of electrospun fibres in addressing these challenges.
- Permeability Evaluation of Flow Behaviors Within Perfusion BioreactorsPublication . Freitas, D.; Almeida, H.A.; Bártolo, P. J.Tissue engineering aims to produce artificial tissue in order to create or repair damaged tissue. It is evident that scaffolds are of extreme importance, because they will be the support structure of the new tissue. This new tissue is cultivated in vitro in a bioreactor in which is placed the scaffold. In order to control the cell culture process inside of a bioreactor, it is essential to know the fluid flow inside the scaffold for an adequate exchange of nutrients and metabolic waste. A novel multifunctional bioreactor with a perfusion system module comprised of three different inlet and outlet membranes is being developed. This research work will evaluate the permeability of the scaffold under the three different inlet and outlet diffusion membranes of the culture chamber.
- IntroductionPublication . Davis, Fred J.; Mohan, Saeed D.; Ibraheem, Muaathe A.This chapter provides a basic introduction to the topics described in this book. The principles of electrospinning, in terms of the influence of an electric field on a droplet of polymer melt or solution is introduced, and a review of some of the experimental parameters, and their relationship towards the properties of the fibres produced is given. A brief summary of the types of materials that can be electrospun is included, together with methods for their characterisation. Finally, a short review of potential applications for electrospun fibres is discussed.
- The Role of Ultrasound Imaging of Musculotendinous Structures in the Elderly PopulationPublication . Carrão, Luis Miguel Costa; Santos, Rute; Espanha, Margarida; Armada-da-Silva, Paulo; Amaral, Ana; Amado, Sandra; Almeida, Henrique de Amorim; Pascoal-Faria, Paula; Veloso, AntónioUltrasound (US) is a noninvasive and real-time method that allows the evaluating muscles and tendons. The enhanced echo-intensity (EI) on ultrasonography images of skeletal muscle is believed to reflect changes in muscle quality (MQ), and these changes accompany aging. Also related to aging, and that may more severely affect women than men, is the well-known loss of skeletal muscle mass. Often associated with the accumulation of connective tissues (e.g., adipose), it affects muscle strength and MQ and causes functional impairment. This chapter demonstrates the potential use of US imaging for assessing muscle changes associated with aging and functional decline.
- Controlling Morphology Using Low Molar Mass NucleatorsPublication . Mitchell, Geoffrey; Wangsoub, Supatra; Nogales, Aurora; Davis, Fred J.; Olley, Robert H.Crystallisation is a hugely important process in physical sciences and is crucial to many areas of, for example, chemistry, physics, biochemistry, metallurgy and geology. The process is typically associated with solidification, for example in the purification of solids from a heated saturated solution familiar to all chemistry undergraduates. Crystalline solids are also often the end result of cooling liquids, or in some cases gases, but in order to form require nucleation, in the absence of nucleation supercoiling of liquids well below the melting point is possible (Cava-gna, 2009). The quality of crystals, as gauged by size and levels of order is highly variable, and may depend on factors such as material purity and the rate of cool-ing; rapid cooling may result in poor crystallisation, or even the formation of amorphous materials with no long range order. In geological systems rates of cooling may vary over many orders of magnitude, for example obsidian is a large-ly amorphous material produced when lava is rapidly cooled (Tuffen, 2003), while the gypsum crystals found in the Cueva de los Cristales in Chihuahua, Mexico can reach 10 metres in length (Figure 1) and are formed over hundreds of thousands of years. In this latter case the formation of such large spectacular structures as shown in Figure 1 can only be explained by a low nucleation rate (García-Ruiz, 2007; Van Driessche, 2011).