Analysis of process variables via CFD to evaluate the performance of a FCC riser

Feedstock conversion and yield products are studied through a 3D model simulating the main reactor of the fluid catalytic cracking (FCC) process. Computational fluid dynamic (CFD) is used with Eulerian-Eulerian approach to predict the fluid catalytic cracking behavior. The model considers 12 lumps with catalyst deactivation by coke and poisoning by alkaline nitrides and polycyclic aromatic adsorption to estimate the kinetic behavior which, starting from a given feedstock, produces several cracking products. Different feedstock compositions are considered. The model is compared with sampling data at industrial operation conditions. The simulation model is able to represent accurately the products behavior for the different operating conditions considered. All the conditions considered were solved using a solver ANSYS CFX 14.0. The different operation process variables and hydrodynamic effects of the industrial riser of a fluid catalytic cracking (FCC) are evaluated. Predictions from the model are shown and comparison with experimental conversion and yields products are presented; recommendations are drawn to establish the conditions to obtain higher product yields in the industrial process

Robustness of an existing pre-stressed concrete bridge

Robustness has been appointed as a desirable property of systems in order to avoid significant indirect consequences caused by extreme events. In fact, robustness is usually related to global failure or collapse. Nevertheless, its definition is not consensual, having led researchers to propose several quantitative measures. In this work, an intuitive framework for the assessment of robustness as a probabilistic performance indicator of bridges to be applied either to ultimate limit states or service limit state is discussed. The research strategy consists in a review of the state-of-art of robustness of structures, aiming to identify the suitable quantitative procedures to assess system robustness and its contributing attributes. A non-linear finite element model of an existing pre-stressed concrete bridge was used to assess bridge structural performance when it is subjected to several damage scenarios. By means of a probabilistic approach, the load carrying capacity and structural safety are evaluated through advanced reliability analysis techniques.The authors would like to thank ISISE - Institute for Sustainability and Innovation in Structural Engineering (PEst-C/ECI/UI4029/2011 FCOM-01-0124-FEDER-022681), FCT Portuguese Scientific Foundation for the research grant PD/BD/113677/2015. This study also received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement No. 606229. Also the collaboration and information provided by the professor Antonio Abel Henriques is gratefully acknowledged

Analytical model for the development strategy of a low-density territory: The Montesinho Natural Park

Montesinho Natural Park is one of the largest Portuguese natural protected areas, presenting good biodiversity and a cultural heritage with a strong connection to the territory and its people. It constitutes a low-density territory, characterized by a human and social landscape based on community practices, such as joint aid and the community use of goods and means of agricultural production, which have contributed to the construction of the “transmontana” identity and to the richness of the habitats. The promotion of the sustainable development of this low-density rural region demands the understanding of its specificities and an appropriate approach to grasp its challenges and develop effective management tools, allowing to preserve and exploit the region’s potential from various perspectives. The purpose of this article is to develop an analytical model using a literature review and a survey of the region’s specificities. This analytical model intends to provide the basis for designing and assessing sustainable development solutions, increasing local entrepreneurship and community empowerment through regional dynamism, with a focus on environment and heritage preservation, universal tourism accessibility, collective memory and endogenous product development. The suggested model adopts an interdisciplinary perspective and stresses that, in order to ensure that the new initiatives will contribute to the territory’s sustainable development, they should be scrutinized by asking four main questions: Is the initiative promoting the rural development of the territory through the creation of synergies between agroforestry and tourism activities? Is the initiative promoting an inclusive and sustainable tourism that is based on the territory’s resources? Are heritage and collective memory being preserved and valued through the initiative? Is the initiative promoting the empowerment of local communities?info:eu-repo/semantics/publishedVersio

Deformation of quantum mechanics in fractional-dimensional space

A new kind of deformed calculus (the D-deformed calculus) that takes place in fractional-dimensional spaces is presented. The D-deformed calculus is shown to be an appropriate tool for treating fractional-dimensional systems in a simple way and quite analogous to their corresponding one-dimensional partners. Two simple systems, the free particle and the harmonic oscillator in fractional- dimensional spaces are reconsidered into the framework of the D-deformed quantum mechanics. Confined states in a D-deformed quantum well are studied. D-deformed coherent states are also found.Comment: 12 pages, some misprints have been corrected, two figures are adde

Parasitism by Campoletis flavicincta on Spodoptera frugiperda in corn.

ABSTRACT: Parasitism by Campoletis flavicincta (Ashmead) (Hymenoptera: Ichneumonidae) on Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) and consequent reduction of production losses were evaluated on caged corn plants in the field. Treatments consisted of plots infested with 0 (control), 15 and 30 pairs of C. flavicincta with egg masses per cage and plot infested without cage and liberation of the parasitoid. Parasitoid release was done when S. frugiperda larvae were three-day-old. Fifty corn plants (40%) per plot were collected seven days after infestation and S. frugiperda larvae present were reared in glass cups on an artificial diet. Number of S. frugiperda larvae was reduced by C. flavicincta but mortality of the pest and parasitoid sex ratio in laboratory were similar among treatments. Total progeny and female production from collected larvae were similar among densities of released parasitoid. Parasitism rate was higher on 30 than on 15 pairs of C. flavicincta. Damage on corn plants at seven and 14 days after S. frugiperda infestation had similar grades at 0, 15 or 30 C. flavicincta pairs and higher values than the plots without cage. Damage by S. frugiperda was lower at 30 C. flavicincta pairs after 21 days of infestation. Final stand, stand reduction by plant death and corn productivity were similar among treatments RESUMO: O objetivo deste trabalho foi avaliar o potencial do parasitóide Campoletis flavicincta (Ashmead) (Hymenoptera: Ichneumonidae) no controle de Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) em plantas de milho protegidas por gaiolas no campo. Os tratamentos consistiram de parcelas infectadas com 0 (controle), 15 e 30 casais de C. flavicincta liberados por gaiola e parcela infestada, além de parcelas sem gaiola e sem liberação do parasitóide. C. flavicincta foi liberado quando as larvas de S. frugiperda estavam com três dias de idade. Em cada parcela, 40% das plantas foram colhidas sete dias após a infestação, e as larvas de S. frugiperda presentes foram transferidas para copos com dieta artificial. C. flavicincta reduziu o número de larvas, mas a mortalidade natural das larvas e a razão sexual do parasitóide emergido em laboratório foram semelhantes entre tratamentos. A produção de progênie e de progênie fêmea por C. flavicincta foi semelhante nas amostras de 15 e 30 casais, mas a taxa de parasitismo foi maior nas amostras de 30 casais do que nas de 15. Os danos às plantas por larvas de S. frugiperda, aos sete e 14 dias após a infestação, foram semelhantes entre as parcelas com 0, 15 ou 30 casais de C. flavicincta, maiores do que nas parcelas sem gaiola. Esses danos foram menores nas parcelas de 30 casais do parasitóide, após 21 dias da infestação. O estande final, redução no estande pela morte das plantas e a produtividade do milho foram semelhantes entre tratamentos

Interação entre doses de reguladores e consistência do ramo no enraizamento de miniestacas de pinhão-manso.

Foi avaliado o efeito de cinco concentrações de auxinas (0, 500, 1000, 1500 e 2000 mg.ℓ-1 ) (ANA e AIB), na indução da formação de raizes adventícias em duas consistências de miniestacas (herbácea e lenhosa) de pinhão manso. O delineamento experimental utilizado foi inteiramente casualizado em arranjo fatorial 2x2x5, com quatro repetições. O ensaio foi desenvolvido na Embrapa Meio-Norte, Teresina-PI. Após 45 dias as miniestacas lenhosas apresentaram melhor capacidade regenerativa, obtendo um percentual de enraizamento oito vezes superior. Ocorreu interação entre reguladores e consistências de miniestacas, sendo que o uso de AIB em miniestacas lenhosas proporcionou um valor 42,4% superior, com o uso de ANA, não ocorrendo diferença entre reguladores para miniestacas herbáceas. Diante desses resultados, pode-se sugerir o uso de miniestacas lenhosas para propagação vegetativa do pinhão-manso, podendo-se fazer uso de AIB na concentração de 500 mg.ℓ-1

Finding co-solvers on Twitter, with a little help from Linked Data

In this paper we propose a method for suggesting potential collaborators for solving innovation challenges online, based on their competence, similarity of interests and social proximity with the user. We rely on Linked Data to derive a measure of semantic relatedness that we use to enrich both user profiles and innovation problems with additional relevant topics, thereby improving the performance of co-solver recommendation. We evaluate this approach against state of the art methods for query enrichment based on the distribution of topics in user profiles, and demonstrate its usefulness in recommending collaborators that are both complementary in competence and compatible with the user. Our experiments are grounded using data from the social networking service Twitter.com

Influência de substratos e tamanho de recipientes na formação de mudas de pinhão-manso.

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