Development of a laboratorial robotized filament winding equipment

Filament winding is the mostly suitable technology to produce at large volume scale structural composite parts presenting revolution form, such as pressure and non-pressure vessels, tanks and pipes, aircraft fuselage, helicopter blades, etc. [1, 2]. Such process allows optimising the deposition and orientation of continuous reinforced fibres in order to manufacture the best performance and customised composite part for each specific application. Another advantage of this technological processing method is the possibility it gives of using almost all continuous reinforcing fibres (carbon, glass, aramid) and plastic matrices (both thermosetting and/or thermoplastic). As the investment for acquiring a filament winding equipment was too much high, the Pole for Innovation in Polymer Engineering (PIEP) decided to use its proper know-how to self-develop an own robotised filament winding equipment for laboratorial use. The aim of such equipment is to support R&D projects with industrial companies concerning the production of filament wound scaled prototype parts for testing, optimising and improving fibre deposition trajectories, study the complex shape manufacturing, testing the application of new fibres and matrices, etc. This paper will present the developed and built robotised filament winding equipment and will discuss its major possibilities, trajectories and software data acquisition capabilities and the results obtained on composite parts manufactured by it.FCT projeto SFRH/BD/60852/200

Performance indicators in the construction industry: a study with Portuguese companies

This paper aims to study the use of performance indicators (PIs) by business managers in the civil construction sector in a region that encompasses eight districts located in the north of Portugal. Through the literature review, it was possible to gather a list of twenty potential PIs used in this sector. Subsequently, a questionnaire was applied to a sample of construction companies from this region. A statistical analysis of the data collected allowed to identify the twelve most used and most important PIs for the companies surveyed. The results indicate that the companies involved in this study mainly use the traditional financial measures, however, recognize that non-financial measures, namely the customer satisfaction index, employee satisfaction, internal customer satisfaction index, and the training of employees, are increasingly important for the success of companies. The study also analysis the criteria to select PIs, its main benefits, and difficulties faced by companies on their usage.INCT-EN - Instituto Nacional de Ciência e Tecnologia para Excitotoxicidade e Neuroproteção(UID/CEC/00319/2019

Composite pressure vessels for commercial applications

A new generation of composite pressure vessels for large scale market applications has been studied in this work. The vessels consist on a plastic liner wrapped with a filament winding glass fibre reinforced polymer matrix structure. A polyethylene (PE) was selected as liner for water at room temperatures applications and a thermosetting resin was used as matrices in the glass reinforced filament wound laminate. For applications having higher service temperatures, such as, termal accumulators and solar panel vessels, thermoplastics presenting greater temperature performance, for example, polypropylene (PP), polyamide (PA), polycarbonate (PC) Polyvinylidene difluoride (PVDF) or even thermosettings are being studied for application as vessel liners.Agencia de Inovação (ADI) através do projeto QREN 21538 – HERMOCOMPRESS e Fundação para a Ciência e a Tecnologia (FCT

A modular reactor to simulate biofilm development in orthopedic materials

Surfaces of medical implants are generally designed to encourage soft- and/or hard-tissue adherence, eventually leading to tissue- or osseo-integration. Unfortunately, this feature may also encourage bacterial adhesion and biofilm formation. To understand the mechanisms of bone tissue infection associated with contaminated biomaterials, a detailed understanding of bacterial adhesion and subsequent biofilm formation on biomaterial surfaces is needed. In this study, a continuous-flow modular reactor composed of several modular units placed in parallel was designed to evaluate the activity of circulating bacterial suspensions and thus their predilection for biofilm formation during 72 h of incubation. Hydroxyapatite discs were placed in each modular unit and then removed at fixed times to quantify biofilm accumulation. Biofilm formation on each replicate of material, unchanged in structure, morphology, or cell density, was reproducibly observed. The modular reactor therefore proved to be a useful tool for following mature biofilm formation on different surfaces and under conditions similar to those prevailing near human-bone implants. [Int Microbiol 2013; 16(3):191-198]Keywords: orthopedic materials · orthopedic conditions · modular reactors · continuous flow · biomaterials · biofilm formatio

Análise multidimensional de consórcios cenoura-alface sob diferentes combinações de densidades populacionais.

Este trabalho teve como objetivo avaliar o desempenho biológico de sistemas consorciados de cenoura e alface, sob diferentes combinações de densidades populacionais, com uso das análises bivariada de variância e envoltória de dados (DEA). O delineamento experimental usado foi o de blocos ao acaso completos, com cinco repetições, com os tratamentos arranjados em esquema fatorial 4x4. Os tratamentos resultaram da combinação de quatro populações de plantas de cenoura (40, 60, 80 e 100% da população recomendada no cultivo solteiro - PRCS) com quatro populações de plantas de alface (40, 60, 80 e 100% da PRCS). As populações recomendadas para os cultivos solteiros da cenoura e alface foram 500 mil e 250 mil plantas por hectare, respectivamente. Tanto o método bivariado como o método de análise de envoltória de dados são bastante eficazes na discriminação dos melhores sistemas de cultivo consorciados, por meio dos rendimentos das culturas. Os resultados da eficiência produtiva, medidos por modelos DEA, permitem uma análise estatística simples do ensaio consorciado. A robustez do método de análise bivariada de variância assegura a validade dos resultados.Título em inglês: Multidimensional analysis of carrot-lettuce intercroppings under different combinations of population densities

Carbon nanomaterials for the purification of antileukemic drugs

Getting older is the biggest risk factor for most fatal diseases, including cancer, heart disease and Alzheimer. To overcome such age-related society diseases, it is crucial to optimize the production and purification of biopharmaceuticals, such as nucleic acid-based products, antibodies and recombinant proteins and enzymes. Low cost production combined with high purity levels allow their routinely use by a widespread population. Continuous progresses have been made for the development of recombinant therapeutic enzymes. L-asparaginase (LA) is an antileukemic biopharmaceutical enzyme of current high-cost. LA is produced via fermentation and its purification usually comprises several steps that account up to 80% of its total production cost (1). This work aims to develop sustainable technologies to extract and purify LA. Reusable functionalized nanomaterials, namely carbon nanomaterials (CNTs), are used as cost-effective purification techniques for the target enzyme. Initially, the synthesis and modification of CNTs was performed. Different CNTs were obtained and used for the purification of LA. Commercial LA was used for the first purification tests, in order to understand the behaviour of the enzyme in contact with the nanomaterial. Experimental conditions, such as pH, and material/LA ratio, contact time were optimized. LA activity was quantified by Nessler reaction (2). The first results reveal a total adsorption of LA by the CNTs. Depending on the CNT functionalization/ treatment, different values of recovered activity of LA were obtained. The modified CNTs are shown to be very promising nanomaterials for the purification of LA. The LA was easily attached to CNTs by adsorption under mild conditions. CNTs supports can be a real alternative for a single step immobilization/purification of LA.publishe

Influência da maceração sobre a coloração e composição físico-química de vinhos tintos tropicais Cabernet Sauvignon

O objetivo do presente trabalho foi avaliar a qualidade do vinho tinto ?Cabernet Sauvignon? elaborado no Submédio do Vale do São Francisco com diferentes tipos e tempos de duração da maceração, a fim de avaliar como essa etapa influencia nos parâmetros físico-químicos e colorimétricos do vinho dessa variedade, a fim de propor melhorias para a elaboração do produto na região, visto a importância mundial da cultivar

Immobilization of L-asparaginase towards surface-modified carbon nanotubes

L-asparaginase (ASNase, EC 3.5.1.1) is an enzyme that catalyzes L-asparagine hydrolysis into L-aspartic acid and ammonia and is mainly applied in pharmaceutical and food industries [1]. The ASNase currently commercialized for pharmaceutical purposes is produced from two main bacterial sources: recombinant Escherichia coli and Erwinia chrysanthemi. However, some disadvantages are associated with its free form, such as the shorter half-life [2]. Immobilization of ASNase has been proposed as an efficient approach to overcome this limitation [3]. In this work, a straightforward method, including the functionalization of multi-walled carbon nanotubes (MWCNTs) through a hydrothermal oxidation treatment with nitric acid, and the immobilization of ASNase by adsorption over pristine and modified MWCNTs was investigated. Different operation conditions, including pH, contact time, ASNase/MWCNT mass ratio, and the operational stability of the immobilized ASNase were evaluated. The characterization of the ASNase-MWCNT bioconjugate was addressed using different techniques, namely Transmission Electron Microscopy (TEM), Thermogravimetric analysis (TGA), and Raman spectroscopy. Functionalized MWCNTs showed promising results, with an immobilization yield and a relative recovered activity of commercial ASNase above 95%, under the optimized adsorption conditions (pH 8, 60 min of contact and 1.5´10–3 g.mL-1of ASNase). The ASNase-MWCNT bioconjugate also showed improved enzyme operational stability (6 consecutive reaction cycles without activity loss), proving its suitability for application in industrial processes.publishe

Immobilization of L-asparaginase towards surface-modified carbon nanotubes

L-asparaginase (LA) is an enzyme that catalyzes L-asparagine hydrolysis into L-aspartic acid and ammonia and is mainly applied in pharmaceutical and food industries. The LA currently commercialized for pharmaceutical purposes is produced from two main bacterial sources: recombinant Escherichia coli and Erwinia chrysanthemi. However, some disadvantages are associated with its free form, such as the shorter half-life. Immobilization of LA has been proposed as an efficient approach to overcome this limitation. In this work, a straightforward method, including the functionalization of multi-walled carbon nanotubes (MWCNTs) through a hydrothermal oxidation treatment and the immobilization of LA by adsorption over pristine and modified MWCNTs was investigated. Different operation conditions, including pH, contact time, ASNase/MWCNT mass ratio, and the operational stability of the immobilized LA, were evaluated. The characterization of the LA-MWCNT bioconjugate was addressed using different techniques, namely Transmission Electron Microscopy (TEM), Thermogravimetric analysis (TGA), and Raman spectroscopy. Functionalized MWCNTs showed promising results, with an immobilization yield and a relative recovered activity of commercial LA above 95%, under the optimized adsorption conditions (pH 8, 60 min of contact, and 1.510–3 g.mL-1 of LA). The LA-MWCNT bioconjugate also showed improved enzyme operational stability (6 consecutive reaction cycles without activity loss), proving its suitability for application in industrial processes.publishe