The role of the compressor isentropic efficiency on non-intrusive refrigerant side characterization of transcritical CO2 heat pump water heaters

Characterizing the refrigerant side of heat pump water heaters (HPWHs) can be intrusive and expensive. On the other hand, direct external measurement techniques can be unfeasible, particularly in commercial HPWHs for residential applications. Non-intrusive in-situ characterization methods have already been successfully implemented in subcritical heat pumps, providing the refrigerant mass flowrate and the equipment energy performance, by using contact temperature sensors and electric power meters. Subcritical suction and discharge specific enthalpies necessary to apply the method can be obtained from the measured temperatures and their corresponding saturation pressures. Nevertheless, this approach does not apply to the transcritical CO2 HPWHs. In the supercritical region, temperature and pressure are independent variables, and an iterative process regarding the compressor isentropic efficiency has to be considered. However, when isentropic efficiency data is not available, an additional procedure is required, using a validated gas cooler model to verify the physical reliability of the numerical solutions.The present study was developed in the scope of the Smart Green Homes Project [POCI-01- 0247-FEDER- 007678], a co-promotion between Bosch Termotecnologia S.A. and the University of Aveiro. It is financed by Portugal 2020 under the Competitiveness and Internationalization OP, and by the European Regional Development Fund (ERDF). This work was funded by the grant SFRH/BD/148378/2019 and the projects UIDB/00481/2020 and UIDP/00481/2020 – FCT-Fundação para a Ciência e Tecnologia; and CENTRO-01- 0145-FEDER-022083 – Centro2020, under the PORTUGAL 2020 Partnership Agreement, through the ERDF

Paisajes culturales agrarios del estado Mérida,Venezuela

Este trabalho aborda a interpretação das paisagens culturais agrárias no estado de Mérida, na Cordilheira dos Andes venezuelanos, adaptado a uma classificação dos tipos bioclimáticos. No "Andar SubAndino", acima de 400m de altitude, domina a paisagem com banana, árvores de fruto, e criação de gado (para produção de carne e leite), enquanto que entre 400 e 1700m a paisagem predominante é café sob sombra em ambientes úmidos e campos de cana de açúcar em ambientes secos. No "Andar Andino", entre 1700 e 2300m predomina uma produção intensiva de hortaliças e tubérculos (principalmente de batatas) em ambientes húmidos, enquanto ambientes secos apresentam uma paisagem relíquia de antigos campos de trigo. O sector da pecuária é dominado por gado de leite. Elevações de 2300 a 3000m são dominadas pela agricultura comercial intensiva dos pequenos e médios produtores de legumes, batatas e flores; assim como a pecuária leiteira e piscicultura de truta. No "Andar AltiAndino" existem culturas intensivas e extensivas, e criação de gado de leite entre 3000 e 4000m, enquanto acima de 4000m há uma pastagem básica muito extensa.En este trabajo se aborda la interpretación de los paisajes culturales agrarios del estado Mérida, en los Andes venezolanos, utilizando una clasificación por pisos bioclimáticos. En el “Piso Subandino”, hasta los 400m de elevación, predomina el paisaje con plátano (banana), árboles frutales, y ganadería vacuna extensiva (producción de carne y leche), mientras que entre los 400 y 1700m el paisaje predominante es el de cafetales bajo sombra en ambientes húmedos y de caña de azúcar en ambientes más secos. En el “Piso Andino”, entre los 1700 y 2300m predomina la producción intensiva de hortalizas, papa y ajo en ambientes húmedos, mientras que en ambientes secos queda un paisaje relicto del cultivo del trigo de épocas pretéritas. En el sector pecuario predomina la ganadería de altura para producción láctea. En elevaciones de 2300 a 3000m predomina una agricultura de tipo comercial e intensiva de pequeños y medianos productores de hortalizas, papas y flores; así como ganadería de altura y piscicultura de truchas. En el “Piso Altiandino” hay cultivos intensivos y extensivos, y ganadería extensiva entre 3000 y 4000m, mientras que en las tierras por sobre 4000m existe un pastoreo básico muy extensivo.This work deals with the interpretation of agrarian cultural landscapes in Mérida State, in the Venezuelan Andes, adapted to a classification of bioclimatic belts. In the "SubAndean bealt", up to 400m of elevation, the landscape with banana, fruit trees and cattle ranching (for meat and milk production) dominates, while between 400 and 1700m the predominant landscape is coffee plantations under shade in moist environments and sugarcane fields in dry environments. In the "Andean bealt", between 1700 and 2300m predominates an intensive production of vegetables and tubercles (mainly potatoes) in humid environments, while the dry environments exhibit a relict landscape of past wheat fields. The livestock sector is dominated by dairy-cattle ranching. Elevations of 2300 to 3000m are dominated by intensive commercial agriculture of small and medium producers of vegetables, potatoes and flowers, as well as dairy-cattle ranching and trout fish-farming. In the "HighAndean bealt" there are intensive and extensive crops, and cattle ranching between 3000 and 4000m, while above 4000m there is a very basic extensive-grazing

Dynamical behaviour of rigid block structures subjected to earthquake motion

This paper studies the dynamic behaviour of rigid-block structures under seismic behaviour. For this purpose, an experimental investigation has been carried out on the rocking response of single blocks, and ensembles of two and three blocks structures. These structures were subjected to three different base motions: free rocking, harmonic and random excitations. The tests were performed at the seismic table of the National Laboratory of Civil Engineering (LNEC) of Portugal.Project ECOLEADER Group 4.Fundação para a Ciência e Tecnologia - SFRH/BPD/17449/2004; SFRH/BD/9014/2002

Stress and deformation in tubular metallic parts of auto seats

In order to assess the structural and material behaviour in particular the deformation and failure in lightweight metallic tubular structural parts of auto seats a pseudo-dynamic procedure was devised. The deformation of circular section tubes subjected to centred transversal force is assessed by rugometric and microtopographic optical inspection.(undefined

Integrated didactics: an example of a curriculum model enhancing knowledge crossing

In this paper, we introduce an innovative course in the Portuguese Context, the Master's Course in “Integrated Didactics in Mother Tongue, Maths, Natural and Social Sciences”, taking place at the Lisbon School of Education and discussing in particular the results of the evaluation made by the students who attended the Curricular Unit - Integrated Didactics (CU-ID). This course was designed for in-service teachers of the first six years of schooling and intends to improve connections between different curriculum areas. In this paper, we start to present a few general ideas about curriculum development; to discuss the concept of integration; to present the principles and objectives of the course created as well as its structure; to describe the methodology used in the evaluation process of the above mentioned CU-ID. The results allow us to state that the students recognized, as positive features of the CU-ID, the presence in all sessions of two teachers simultaneously from different scientific areas, as well as invitations issued to specialists on the subject of integration and to other teachers that already promote forms of integration in schools. As negative features, students noted a lack of integrated purpose, applying simultaneously the four scientific areas of the course, and also indicated the need to be familiar with more models of integrated education. Consequently, the suggestions for improvement derived from these negative features. The students also considered that their evaluation process was correct, due to the fact that it was focused on the design of an integrated project for one of the school years already mentioned

Heuristic-based firefly algorithm for bound constrained nonlinear binary optimization

Firefly algorithm (FA) is a metaheuristic for global optimization. In this paper,we address the practical testing of aheuristic-based FA (HBFA) for computing optimaof discrete nonlinear optimization problems,where the discrete variables are of binary type. An important issue in FA is the formulation of attractiveness of each firefly which in turn affects its movement in the search space. Dynamic updating schemes are proposed for two parameters, one from the attractiveness term and the other from the randomization term. Three simple heuristics capable of transforming real continuous variables into binary ones are analyzed. A new sigmoid ‘erf’ function is proposed. In the context of FA, three different implementations to incorporate the heuristics for binary variables into the algorithm are proposed. Based on a set of benchmark problems, a comparison is carried out with other binary dealing metaheuristics. The results demonstrate that the proposed HBFA is efficient and outperforms binary versions of differential evolution (DE) and particle swarm optimization (PSO). The HBFA also compares very favorably with angle modulated version of DE and PSO. It is shown that the variant of HBFA based on the sigmoid ‘erf’ function with ‘movements in continuous space’ is the best, both in terms of computational requirements and accuracy.Fundação para a Ciência e a Tecnologia (FCT

ECONOMIA DO GRUPO KAINGANG DO OESTE PAULISTA NA TERRA INDÍGENA VANUÍRE

This article aims to describe the historical and ethnographic content of the Kaingang group from Oeste Paulista, in the Indigenous Land Vanuíre, and how they promote their economy. The Kaingang are peoples belonging to the Macro-Jê linguistic group, and the Jê family is considered one of the largest indigenous groups from the population point of view. The methodology adopted for the development of this article is based on bibliographic and descriptive typology, using documentary research as a technique. It is hoped to obtain, with this article, a systematic set of information, which, when reaching the objective of the work, can contribute to a better understanding of the economy of the Kaingang group in Western São Paulo, in the Terra Indígena Vanuíre.   KEYWORDS:  Ethnodevelopment; Kaingang; Terra Indígena Vanuíre.Este artículo tiene como objetivo describir el contenido histórico y etnográfico del grupo Kaingang del Oeste Paulista, en la Tierra Indígena Vanuíre, y cómo promueven su economía. Los Kaingang son pueblos pertenecientes al grupo lingüístico Macro-Jê, y la familia Jê es considerada uno de los grupos indígenas más grandes desde el punto de vista poblacional. La metodología adoptada para el desarrollo de este artículo se basa en la tipología bibliográfica y descriptiva, utilizando como técnica la investigación documental. Se espera obtener, con este artículo, un conjunto sistemático de información que, al alcanzar el objetivo del trabajo, puede contribuir a una mejor comprensión de la economía del grupo Kaingang en el Oeste de São Paulo, en la Tierra Indígena Vanuíre.   PALABRAS-CLAVES: Etnodesarrollo; Kaingang; Terra Indígena VanuíreO presente artigo tem como objetivo descrever o conteúdo histórico e etnográfico do grupo Kaingang do Oeste Paulista, na Terra Indígena Vanuíre, e como promovem sua economia.  Os Kaingang são povos pertencentes ao tronco linguístico Macro-Jê, e família Jê, é considerado um dos maiores grupos indígenas do ponto de vista populacional. A metodologia adotada para o desenvolvimento deste artigo parte da tipologia bibliográfica e descritiva, tendo como técnica a pesquisa documental. Espera-se obter, com deste artigo, um conjunto sistematizado de informações, que ao alcançar o objetivo do trabalho, possa contribuir para o melhor entendimento sobre a economia do grupo Kaingang do Oeste Paulista, na Terra Indígena Vanuíre.   PALAVRAS-CHAVE: Etnodesenvolvimento; Kaingang; Terra Indígena Vanuíre

Adsorption of BTX (benzene, toluene, o-xylene, and p-xylene) from aqueous solutions by modified periodic mesoporous organosilica

AbstractThe capacity of a periodic mesoporous organosilica (PMO) to adsorb the aromatic compounds benzene, toluene, o-, and p-xylenes (BTX), which are usually present in produced waters, was investigated under both column and batch processes. The PMO was synthesized by condensation of 1,4 bis(triethoxisilyl)benzene (BTEB) under acidic conditions by using structure-directing agent (SDA) Pluronic P123 in the presence of KCl. Thermogravimetric analysis showed that the presence of the surfactant decreases the thermal stability of the PMO. The small-angle X-ray diffraction pattern, as well as the nitrogen adsorption/desorption isotherm measurements, revealed that the synthesized material has a crystalline structure, with hexagonally-ordered cylindrical mesopores. The adsorption kinetics study indicated an adsorption equilibrium time of 50min and also showed that the data best fitted the pseudo-first order kinetic model. The intraparticle diffusion model was also tested and pointed to the occurrence of such process in all cases. Both Langmuir and Temkin models best represented the adsorption isotherms of toluene; Langmuir and Redlich–Peterson models best represented the data obtained for the other compounds. Adsorption capacity decreases in the order benzene>o-xylene>p-xylene>toluene. Satisfactory results were observed in the application of the synthesized PMO for the removal of BTX from aqueous solution

Tremor in Patients with Inflammatory Bowel Disease

The spectrum of neurological manifestations of Crohn’s disease (CD) and ulcerative colitis (UC) is diverse and not fully understood. In addition to peripheral neuropathy, mild autonomic impairment has been reported. These problems themselves could also result in secondary neurological consequences, such as the exacerbation of enhanced physiological tremor. Indeed, some patients in our cohort complained of tremor. Hence, we hypothesized that enhanced physiological tremor would be more severe in patients with inflammatory bowel disease (IBD) than controls

Red ruby glass from gold nanoparticles obtained by LASiS – a new approach

Currently, most of the red colored glasses are still produced using cadmium sulfoselenide, despite its high toxicity. Alternative solutions, more environmentally friendly, have been sought, most of them going through the use of gold or copper nanoparticle, the color being obtained by striking. This work presents a new methodology for production of a red colored glass by the incorporation of gold nanoparticles in the melt, trying to take advantage of an amorphous silica layer involving the nanoparticles. Gold nanoparticles (AuNP) were produced by laser ablation synthesis in solution (LASiS), using a solution of tetraethyl orthosilicate (TEOS) and isopropanol (IPA). A xerogel was prepared using the TEOS:IPA:AuNp suspension, mixed with a alkaline-earth aluminosilicate colorless glass and melted at 1350 °C producing a glass with an intense and homogeneous ruby red color without the need of a striking stage.publishe