Exergy efficiency optimization for gas turbine based cogeneration systems

Energy degradation can be calculated by the quantification of entropy and loss of work and is a common approach in power plant performance analysis. Information about the location, amount and sourc es of system deficiencies are determined by the exergy analysis, which quantifies the exergy destruction. Micro - gas turbines are prime movers that are ideally suited for cogeneration applications due to their flexibility in providing stable and reliable power. This paper presents an exergy analysis by means of a numerical simulation of a regenerative micro - gas turbine for cogeneration applications . The main objective is to study the best configuration of each system component , considering the minimization of the system irreversibilities . Each component of the system was evaluated considering the quantitative exergy balance . Subsequently the optimization procedure was applied to the mathematical model that describes the full system. The rate of irreversibility, efficiency and flaws are highlighted for each system component and for the whole system. The effect of turbine inlet temperature change on plant exergy destruction was also evaluated . The results disclose that considerable exergy destruction occurs in the combustion chamber. Also, it was revealed that the exergy efficiency is expressively dependent on the changes of the turbine inlet temperature and increases with the latter .The authors would like to express their acknowledgments for the support given by the Portuguese F01mdation for Science and Technology (FCT) through the PhD grant SFRH/BD/62287/2009. This work was financed by National Funds-Portuguese Foundation for Science and Technology, under Strategic Project and PEst-OE/EME/UI0252/2011 and also the PEst-C/EME/UI4077/2011

A CFD study of a pMDI plume spray

Uncorrected proofAsthma is an inflammatory chronic disease characterized by airway obstructions disorders. The treatment is usually done by inhalation therapy, in which pressurized metered-dose inhalers (pMDIs) are preferred devices. The objective of this paper is to characterize and simulate a pMDI spray plume by introducing realistic factors through a computational fluid dynamics (CFD) study. Numerical simulations were performed with Fluent® software, by using a three-dimensional “testbox” for room environment representation. A salbutamol/HFA-134a formulation was used for characterization, whose properties taken as input for the CFD simulations. Spray droplets were considered to be composed by ethanol, salbutamol and HFA-134a. Propellant evaporation was taken into consideration, as well as, drag coefficient correction. Results showed an air temperature drop of 3.3 °C near the nozzle. Also, an increase in air velocity of 3.27 m/s was noticed. The CFD results seem to be in good agreement with Dunbar (1997) data on particle average velocity along the axial distance from the nozzle.National Funds-Portuguese Foundation for Science and Technology, under Strategic Project PEst-C/EME/UI4077/2011 and PEst-OE/EME/299UI0252/201

Development of tools to support the production planning in a textile company

Technologies are constantly evolving and so with advances in industry 4.0, its intelligent technologies with production planning and control (PPC) give rise to a smart PPC. Nowadays, one of the fundamental systems in a company is the ERP, since it allows the integration of various information from the different areas belonging to an organization, which allows access to data in real time, among other things. Through a work carried out in a textile company, it was noticeable the need to develop a tool to support its installed ERP system and the respective data control. Thus, it is noted that PPC systems, which include the integration of all areas of a company, must be adapted to its environment, work method and characteristics. With the application of this tool, it was possible to perceive an increase in efficiency and speed in obtaining the desired results, being that it is still under development and could evolve even more.FCT - Fundação para a Ciência e a Tecnologia(UIDB/00319/2020

Numerical study of the unsteady flow in simplified and realistic iliac bifurcation models

Cardiovascular diseases are a major cause of death and disability worldwide and they are commonly associated with the occurrence of atherosclerotic plaque deposition in the vessel walls, a process denoted as atherosclerosis. This is a chronic and progressive inflammatory disease of large-/medium-sized blood vessels that affects blood flow profiles, with the abdominal aorta and its branches being one of the locations prone to the development of this pathology, due to their curvatures and bifurcations. In this regard, the effect of flow patterns was studied and compared for both a simplified three-dimensional model of aorta bifurcation on the iliac arteries and a realistic model of iliac bifurcation, which was constructed from a computational tomography medical image. The flow patterns were analyzed in terms of velocity and wall shear stress distribution, but a special focus was given to the size and location of the recirculation zone. The simulations were performed using the Computational Fluid Dynamics software, FLUENT, taking into account the cardiac cycle profile at the infrarenal aorta. The shear stress and the velocity distribution observed for both models indicated that higher shear stress occurred along the flow divider wall (inner wall) and low shear stress occurred along the outer walls. In addition, the results demonstrated that the wall shear stress profiles were deeply affected by the transient profile of the cardiac cycle, with the deceleration phase being the most critical phase to the occurrence of backflow.This work was supported by FCT—Fundação para a Ciência e Tecnologia through the R&D Units Project Scope: UIDB/00319/2020, UIDB/04077/2020, and NORTE-01-0145-FEDER-030171, funded by COMPETE2020, NORTE 2020, PORTUGAL 2020, and FEDER

Occupational safety & ergonomics training of future industrial engineers: a project-based learning approach

As industries push for continuous technological innovation, the need to balance work demands and human capabilities and to ensure the workers' safety is now more pressing than ever. Therefore, the training of future industrial engineers must promote the development of different skills, including in the Occupational Safety & Ergonomics (OS&E) domain. Based on this assumption, Project-Based Learning (PjBL) is an active learning methodology where students develop projects in teams as a means of building effective professional skills and knowledge. The current study aims at evaluating the impact of PjBL in effective learning on OS&E, based on the participants' perceptions. PjBL has been applied in the 7th semester of the Integrated MSc in Industrial Engineering and Management at a Portuguese University. In the last years, different companies in the northern region of Portugal have participated in this PjBL, welcoming the students to develop the projects. The current study included a documental analysis that was also developed, considering the final technical reports developed by the students during a scholar semester. In addition, a questionnaire for data collection was developed and applied to the participants. The sample (n=64) included university students who participated in the referred PjBL, their teachers, and the supervisors of the companies where the Project was developed. Globally, the participants' perceptions reveal that the PjBL participants attribute a positive evaluation to this learning methodology, concerning the development of technical (on OS&E) and transversal skills.FCT - Fundação para a Ciência e a Tecnologia(UIDB/00319/2020

Shelf-life extension of squid and shrimp skewers through the application of vinegar solutions

info:eu-repo/semantics/publishedVersio

Salivary IgA Responses During a Week of Training In Under-15 Soccer Players

Introduction There is an apparent consensus around the idea that light exercise can improve the immune response whilst strenuous exercise can depress the defense system, including the mucosal immune system, with reduction of salivary immunoglobulin A (IgA) levels. Salivary IgA acts as a main barrier against the colonization of infectious agents. The purpose of this study was to examine the influence in the pattern of salivary IgA responses in an under-15 soccer team, during a training week. Methods The study was performed during the winter training season, in the competitive period. The training sessions were planned by the coaches without any interference from the researchers. Thirteen players (13 to 15 years) were tested before each of four training sessions during a week period. Before and after training, saliva samples were collected and salivary IgA concentrations and secretion rates determined by ELISA. Thirty minutes after each session, rated perceived effort (RPE) was assessed to quantify training load. Changes in pre-training IgA responses were examined based on multilevel modeling regression using polynomial model (model I). Influence of training load was explored including the explanatory variable at level 2 (model lI). Results Multilevel regression analysis showed no differences between training sessions throughout the week. However, significant residual variance at level I (within-individuals) and at level II (between-individuals), in the intercept and slope (i.e., training sessions). Although limited by the small sample size, a curvilinear trend in pre-training IgA response became apparent when individual athletes´ training loads were controlled in the model. The results showed a significant decrement in IgA response pre-training from the first to the second training session (p \u3c 0.05), and a significant exponential increase in IgA response in the next two training sessions (p \u3c 0.05). The significant random effects at level I suggest that the fit of individual responses may need to be validated in larger samples, although the non significant random effects at level II suggest that the mean responses accounting individual training loads describes well the group behavior in pre training IgA responses. Conclusion The specific relationship that appears to be linked to the intensity, duration and type of physical activity were detected in our study. Monitoring mucosal immune parameters during training periods may provide an assessment of the risk status of these young athletes for upper respiratory tract Infections and allow the coach to have an effective management of periodization

Consenso Técnico para a determinação do status da proteína HER2 por imunocitoquímica em carcinoma da mama

A determinação do status da proteína HER2 por imunocitoquímica é uma metodologia fundamental para o diagnóstico, prognóstico e indicação terapêutica no carcinoma da mama, nomeadamente para o encaminhamento terapêutico com Herceptin®/trastuzumab. O estabelecimento desta terapêutica nas vertentes adjuvante ou neoadjuvante, e até em doença metastática, tem vindo a acentuar a importância da determinação do referido status de modo a melhor responder às necessidades dos doentes. Sendo a imunocitoquímica o método validado para determinação do status HER2 em carcinoma da mama, é de extrema importância definir linhas de orientação para a sua correta performance como tem sido estabelecido em diversos países em todo o mundo. A área científica de Anatomia Patológica, Citológica e Tanatológica da Escola Superior de Tecnologia da Saúde de Lisboa (APCT-ESTeSL) e a Associação Portuguesa de Técnicos de Anatomia Patológica (APTAP) reuniram um painel de especialistas para a construção e estabelecimento de linhas de orientação técnica para a determinação do status HER2 em carcinoma da mama para a realidade portuguesa. Pretende-se com este consenso criar linhas de orientação técnicas para a construção, validação e manutenção do teste imunocitoquímico para determinação do status HER2 em carcinoma da mama, no que diz respeito à realidade portuguesa. Todas as orientações aqui descritas têm em conta o estado da arte atual no que diz respeito à determinação do status HER2 por imunocitoquímica em carcinoma da mama, bem como a experiência pessoal e académica de cada um dos membros do painel de especialistas que a subscrevem

Genomic diversity of Oenococcus oeni from different winemaking regions of Portugal

Oenococcus oeni is an alcohol-tolerant, acidophilic lactic acid bacterium that plays an important role in the elaboration of wine. It is often added as a starter culture to carry out malolactic conversion. Given the economic importance of this reaction, the taxonomic structure of this species has been studied in detail. In the present work, phenotypic and molecular approaches were used to identify 121 lactic acid bacteria strains isolated from the wines of three winemaking regions of Portugal. The strains were differentiated at the genomic level by M13-PCR fingerprinting. Twenty-seven genomic clusters represented by two or more isolates and 21 single-member clusters, based on an 85% similarity level, were recognized by hierarchic numerical analysis. M13-PCR fingerprinting patterns revealed a high level of intraspecific genomic diversity in O. oeni. Moreover, this diversity could be partitioned according to the geographical origin of the isolates. Thus, M13-PCR fingerprint analysis may be an appropriate methodology to study the O. oeni ecology of wine during malolactic fermentation as well as to trace new malolactic starter cultures and evaluate their dominance over the native microbiota

Seleção de fungos produtores de β-D-frutosiltransferase por fermentação em estado sólido

A enzima β-D-frutosiltransferase é responsável pela síntese de FOS (frutooligossacarídeos) a partir de sacarose por reação de transfrutosilação é produzida por diferentes micro-organismos, principalmente por fungos filamentosos. O objetivo deste trabalho foi selecionar a melhor linhagem fúngica produtora da -D-frutosiltransferase por fermentação em estado sólido, bem como o método de extração. A fermentação em estado sólido utilizando o substrato farelo de trigo umedecido com solução de sacarose atingindo 70% de umidade na concentração de esporos de 107 no tempo de 96 horas de crescimento. Todas as linhagens manipuladas apresentaram atividade hidrolítica, no entanto apenas uma linhagem não demonstrou atividade transfrutosilação. O isolado SIS 14 que pertence ao gênero Aspergillus sp. destacou-se pelos maiores valores em atividade no método de extração utilizando água destilada, apresentando 300,90 U/mL na atividade de transfrutosilação e na atividade hidrolítica de 155,74 U/mL. Contudo, pode-se perceber que dos solventes estudados a água destilada foi melhor obtendo o valor em atividade de transfrutosilação, como também a linhagem SIS 14 é promissora para a produção da β-D-frutosiltransferase