64 research outputs found
Assessment of energy use and energy efficiency in two portuguese slaughterhouses
With the objective of characterizing the profile and performance of energy use by slaughterhouses, surveys and audits were performed in two different facilities located in the northeastern region of Portugal. Energy consumption from multiple energy sources was assessed monthly, along with production and costs, for the same reference year. Gathered data was analyzed to identify and quantify the main consuming processes and to estimate energy efficiency indicators for benchmarking purposes. Main results show differences between the two slaughterhouses concerning energy sources, consumption by source and sector, and global energy
efficiency. Electricity is the most used source in both slaughterhouses with a contribution of around 50%, being essentially used for meat processing and refrigeration. Natural gas, in slaughterhouse A, and pellets, in slaughterhouse B, used for heating water take the second place, with a mean contribution of about 45%. On average, a 62 kgoe/t specific energy consumption (SEC) was found, although with differences between slaughterhouses. A prominent negative correlation between SEC and carcass production was found specially
in slaughterhouse A. Estimated Specific Energy Cost and Greenhouse Gases Intensity (GHGI) show mean values of about 50 €/t and 1.8 tCO2e/toe, respectively. Main results show that there is a significant margin for improving energy efficiency and therefore lowering costs in this type of non-energy intensive industries.info:eu-repo/semantics/publishedVersio
Pre-andean serpentinite-chromite orebodies in the Eastern Cordillera of Central Perú, Tarma province
Ultramafic rocks occur scattered along a 300 km long NNW-SSE trending belt, lying parallel to the central Peruvian Andean direction in the Cordillera Oriental, from Tarma (JunÃn Dept.) to Huánuco and Tingo MarÃa (Huánuco Dept.). The Tarma occurrences (Tapo and Acobamba) are studied, as first step of a broader research. The Tapo massif comprises strongly tectonised serpentinites with scarce peridotitic relics, amphibolites and podiform chromitites. It is overthrust on the lower carboniferous metasediments of the andean basement (Ambo Group), and it shows evidences of a pre-andean deformational history, not found in the Ambo Group; the basal thrust plane is folded by Andean tectonics. The two smaller Acobamba occurrences are also allochtonous and show similar tectonic characteristica. Major and trace element compositions of the amphibolites point to a tholeiitic basalt (to picrobasalt) protolith, compatible with an ocean ridge or ocean island environment. Small scale mining worked podiform chromitite lenses and chromite disseminations, strongly deformed, metamorphosed and overprinted by hydrothermal alteration related to deformation. The ores comprise mainly chromite, ferritchromite, spinel, magnetite, ilmenite and scarce sulphides, as well as the secondary minerals stichtite and nimite. Results of this work exclude current interpretations of the Tarma ultramafites as autochtonous igneous intrusives
New data on the deposition age of the volcano-sedimentary Chela Group and its Eburnean basement : implications to post-Eburnean crustal evolution of the SW of Angola
The Chela Group comprises a volcano-sedimentary sequence deposited in a widespread epicratonic basin that extends
to southern of the Lubango region in SW of Angola. The basement rocks of the Chela Group integrate the Eburnean
belt, consisting mainly of gneisses and migmatites, syntectonic foliated peraluminous granites, and late-tectonic
metaluminous granites of the Chela and Gandarengos Mountains. Rb/Sr radiometric age of 2.1 ± 0.1 Ga was
determined for the syntectonic granites whereas the late-tectonic Chela granite yielded a zircon U-Pb age of 1947 ± 5
Ma. This isotopic dating allow us to take it as a maximum age for the Chela Group. Moreover, the porphyritic
calc-alkaline granite of the Gandarengos Mountain and a rhyolitic mass, spatially related to this granite, revealed
U-Pb zircon ages of 1810 ± 11 Ma and 1814 ± 88 Ma, respectively. The rhyolite is intrusive into Tundavala Formation,
base of the Chela Group, and should be the source of the pyroclastites composing the Humpata Formation. The time
interval between 1814-1810 Ma obtained for the volcano-plutonism intrusive into the Chela Group restrains its
minimum age and permits to define the interval 1947-1810 Ma as the main period of deposition of this sedimentary
sequence in a post-orogenic environment. After the deposition of the Chela Group, succeeds a period of crustal
accretion marked by the installation of leucocratic peraluminous granites and an extensional Mesoproterozoic (1.4-1.1
Ga) bimodal magmatism, followed during the Neoproterozoic by deposition of the Damara Supergroup and
development of the Pan-African belt. At that period, any tectonometamorphic event reportable to Grenville-Kibaran
orogeny was not recognized in SW Angola
Parenting and adolescents' self-esteem: the Portuguese context
Este estudio analiza las relaciones entre los estilos parentales y el ajuste psicosocial (autoestima) en la adolescencia dentro del contexto portugués. La muestra estuvo formada por 517 adolescentes, 214 varones (41,39%), con edades entre los 11 y los 18 años. Se usó la Escala de Socialización Parental (ESPA29) para detenninar los estilos parentales (autorizativo, autoritario, indulgente y negligente), y la Escala de Autoestima Multidimensional (AF5) que mide cinco dimensiones de la autoestima: académica, social, emocional, familiar y fÃsica. Los resultados de este estudio mostraron que los adolescentes de familias indulgentes puntuaron igual o incluso mejor que los de familÃas autorizativas en algunos indicadores del ajuste psicosocial. Estos resultados sugieren que la parentalidad autorizativa no está asociada con una mayor autoestima en el contexto portugués. El estudio refiere la necesidad de mayor investigación, teniendo en cuenta nuevos contextos y culturas
Using metaheuristics-based methods to provide sustainable market solutions, suitable to consumer needs
Nowadays the buildings sector is one of the key sectors to achieve sustainability, with the correspondent consumers, in particular, the household consumers, having the need to perform sustainable choices every day, regarding the appliances to be acquired from the market. This is not only due to government’s growing concerns about sustainability but also with the consumers on having sustainable solutions, given the different economic, social (including their comfort) and environmental needs. However, the existence of several electrical appliances on market, with all their different issues, brands and models, together with the several tradeoffs referred before, difficult the consumer’s choices, on having sustainable solutions in the market. Therefore, this work, presents an approach, by using Multi-Attribute Value Theory (MAVT), integrated with metaheuristics, which uses Evolutionary Algorithms (EA) to provide suitable and sustainable market solutions to a consumer, according to its own needs. Based on the achieved solutions and considering the relative importance, given to each consumer, and regarding each dimension of sustainability, it’s possible to achieve several savings, namely electrical and water consumption, CO2 emissions, among others. A case study shall be shown, to demonstrate the applicability of the proposed approach.publishersversionpublishe
Contrasting Ordovician high- and low-pressure metamorphism related to a microcontinent-arc collision in the Eastern Cordillera of Perú (Tarma province)
High-pressure conditions of 11–13 kbar/500–540 °C during maximum burial were derived for garnet amphibolite in the Tapo Ultramafic Massif in the Eastern
Cordillera of Peru using a PT pseudosection approach. A Sm–Nd mineral-whole rock isochron at 465 ± 24 Ma dates fluid influx at peak temperatures of ~600 °C
and the peak of high pressure metamorphism in a rodingite of this ultramafic complex. The Tapo Ultramafic Complex is interpreted as a relic of oceanic crust
which was subducted and exhumed in a collision zone along a suture. It was buried under a metamorphic geotherm of 12–13 °C/km during collision of the
Paracas microcontinent with an Ordovician arc in the Peruvian Eastern Cordillera. The Ordovician arc is represented by the western Marañon Complex. Here, low
PT conditions at 2.4–2.6 kbar, 300–330 °C were estimated for a phyllite–greenschist assemblage representing a contrasting metamorphic geotherm of 32–40
°C/km characteristic for a magmatic arc environment
Evolução e estrutura da zona de cisalhamento dúctil Malpica-Lamego : livro guia da excursão pós-congresso
Metamorphism of chromitites in the Tapo ultramafic massif, eastern Cordillera, Peru
Metamorphosed chromite crystals in massive chromitite ore-bodies from the Tapo ultramafic massif (Peru) show distinct petrographic features and chemical patterns of zoning different from those exhibited by disseminated chromites. The observed differences can be explained in terms of prograde metamorphism up to the lower-amphibolite facies, under the control of the chromite/silicate ratio, chromite grain size and degree of fracturing
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