oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 3 )

2018 ( 22 )

2017 ( 14 )

2016 ( 35 )

Custom range...

Search Results: 1 - 10 of 4119 matches for " Caroline Portilho Trentini "
All listed articles are free for downloading (OA Articles)
Page 1 /4119
Display every page Item
Continuous Catalyst-Free Esterification of Oleic Acid in Compressed Ethanol
Ana Carolina de Araujo Abdala,Vitor Augusto dos Santos Garcia,Caroline Portilho Trentini,Lúcio Cardozo Filho,Edson Antonio da Silva,Camila da Silva
International Journal of Chemical Engineering , 2014, DOI: 10.1155/2014/803783
Abstract: The esterification of oleic acid in a continuous catalyst-free process using compressed ethanol was investigated in the present study. Experiments were performed in a tubular reactor and variables investigated were temperature, pressure, and oleic acid to ethanol molar ratio for different residence time. Results demonstrated that temperature, in the range of 473?K to 573?K, and pressure had a positive effect on fatty acid ethyl esters (FAEE) production. In the experimental range investigated, high conversions can be obtained at low ethanol concentrations in the reaction medium and it was observed that oleic acid to ethanol molar ratios greater than 1?:?6 show no significant increase in conversion. Nonnegligible reaction conversions (>90%) were achieved at 573?K, 20?MPa, oleic acid to ethanol molar ratio of 1?:?6, and 20 minutes of residence time. 1. Introduction Fatty acid, methyl or ethyl, esters can be usually obtained from free fatty acid (FFA) esterification reaction, through vegetable oils hydrolysis followed by the fatty acid esterification or from direct vegetable oils transesterification [1]. The importance of examining the esterification reaction in a more detailed manner is justified by the huge amount and variety of vegetable oils worldwide available for biodiesel production which may have a high percentage of FFA making the conventional alkali-catalyzed transesterification impracticable, since for this process the percentage of FFA needs to be less than 0.5% [2]. Recent studies propose to obtain esters in two reaction steps of substrates with high acidity, consisting of two approaches: (a) esterification of FFA and subsequent transesterification of triglycerides [3–5] or (b) hydrolysis of triglycerides, followed by esterification of fatty acids obtained [6–8]. In these approaches are commonly used chemical catalysts (homogeneous or heterogeneous) or enzymatic catalysts. More recently, the noncatalytic process where is proposed the hydrolysis occurs primarily in subcritical water and subsequent esterification using a solvent in sub- or supercritical [9, 10]. According to the current literature, catalyst-free reactions at high temperature and pressure conditions provide improved phase solubility and decreased mass-transfer limitations; the reaction rate increases significantly in the supercritical state and, thus, the reaction is complete in shorter periods and simpler separation and purification steps [11, 12]. Some studies available in the literature reported the biodiesel production from free fatty acids (FFA) by noncatalytic method at sub-
On a possible connection between Chandler wobble and dark matter
Portilho, Oyanarte;
Brazilian Journal of Physics , 2009, DOI: 10.1590/S0103-97332009000100001
Abstract: chandler wobble excitation and damping, one of the open problems in geophysics, is treated as a consequence in part of the interaction between earth and a hypothetical oblate ellipsoid made of dark matter. the physical and geometrical parameters of such an ellipsoid and the interacting torque strength is calculated in such a way to reproduce the chandler wobble component of the polar motion in several epochs, available in the literature. it is also examined the consequences upon the geomagnetic field dynamo and generation of heat in the earth outer core.
$^{6}_{\Lambda\Lambda}$He and $^{10}_{\Lambda\Lambda}$Be hypernuclei calculations with realistic interactions
Portilho, O.;
Brazilian Journal of Physics , 2003, DOI: 10.1590/S0103-97332003000400040
Abstract: we study the $^{6}_{\lambda\lambda}$he and $^{10}_{\lambda\lambda}$be hypernuclei in the three- and four-body models, respectively, employing harmonic oscillator bases and presently most realistic a-a, a-l and l-l interactions. in order to improve convergence we use correlation functions in the case of $^{10}_{\lambda\lambda}$be. comparison is made with results obtained using similar interactions and other methods, and it is performed an analysis concerning the possibility of a unified description of both hypernuclei.
He and Be hypernuclei calculations with realistic interactions
Portilho O.
Brazilian Journal of Physics , 2003,
Abstract: We study the He and Be hypernuclei in the three- and four-body models, respectively, employing harmonic oscillator bases and presently most realistic alpha-alpha, alpha-lambda and lambda-lambda interactions. In order to improve convergence we use correlation functions in the case of Be. Comparison is made with results obtained using similar interactions and other methods, and it is performed an analysis concerning the possibility of a unified description of both hypernuclei.
Pueblos indígenas. Interculturalidad, colonialidad, política
Florencia Trentini
Runa : Archivo para las Ciencias del Hombre , 2011,
Abstract:
Evaluating the quality of distance learning.. The case of the seminar on methodologies for distance learning in the degree course for trainers at the University of Bologna. With closing reflections from Ira Vannini Valutare la qualità della formazione a distanza. Il caso del Seminario di Metodologie della FaD del corso di Laurea in Formatore dell’Università di Bologna. Con alcune riflessioni conclusive di Ira Vannini.
Graziella Trentini
Ricerche di Pedagogia e Didattica , 2009,
Abstract: Beginning with the academic year 1999/2000, following the reorganisation of degree courses according to the decree 509/99. The Education Faculty at the university of Bologna instituted a new degree course in Training . The course combined theoretical lectures with seminars, workshops and practical experience. The seminar entitled “Methodologies for Distance Learning” was offered over a 5 year period ending in the 2006/7 academic year. It was considered important to evaluate this particular experience. A partire dall’a.a. 1999/2000, in seguito al riordino dei corsi di laurea in base al De-creto 509/99 (“Regolamento recante norme concernenti l’autonomia didattica degli Atenei”) la Facoltà di Scienze della Formazione dell’Università di Bologna istituiva il nuovo Corso in Formatore con un piano di studi dove, insieme ai corsi teorici, partecipavano alla formazione del nuovo laureato triennale attività seminariali, labo-ratoriali e di tirocinio. Il seminario denominato “Metodologie della FaD” è stato ri-proposto nel corso di laurea con diverse modifiche per 5 anni: la sua ultima edizione è stata nell’anno accademico 2006-07. A fronte di questa esperienza pluriennale, si è ritenuto dunque importante fare un bilancio di questa specifica attività formativa.
Optimization of particle bombardment parameters for the genetic transformation of Brazilian maize inbred lines
Petrillo, Caroline Pereira;Carneiro, Newton Portilho;Purcino, Ant?nio álvaro Corsetti;Carvalho, Carlos Henrique Siqueira;Alves, José Donizeti;Carneiro, Andréa Almeida;
Pesquisa Agropecuária Brasileira , 2008, DOI: 10.1590/S0100-204X2008000300012
Abstract: the objective of this work was to develop a genetic transformation system for tropical maize genotypes via particle bombardment of immature zygotic embryos. particle bombardment was carried out using a genetic construct with bar and uida genes under control of camv35s promoter. the best conditions to transform maize tropical inbred lines l3 and l1345 were obtained when immature embryos were cultivated, prior to the bombardment, in higher osmolarity during 4 hours and bombarded at an acceleration helium gas pressure of 1,100 psi, two shots per plate, and a microcarrier flying distance of 6.6 cm. transformation frequencies obtained using these conditions ranged from 0.9 to 2.31%. integration of foreign genes into the genome of maize plants was confirmed by southern blot analysis as well as bar and uida gene expressions. the maize genetic transformation protocol developed in this work will possibly improve the efficiency to produce new transgenic tropical maize lines expressing desirable agronomic characteristics.
Qualified “in shelter” dogs’ evaluation and training to promote successful dog-human relationships  [PDF]
Marilena Sticco, Roberto Trentini, Pia Lucidi
Open Journal of Animal Sciences (OJAS) , 2011, DOI: 10.4236/ojas.2011.13018
Abstract: The phenomenon of dogs’ relinquishment in Italy has become a social evil, although many laws exist to regulate animal protection and lately, the act of abandonment has become criminalised (law n.189/2004, enforced by law n.201/2010). Adoption from shelters seems to be the only way to have a controlled, microchipped population of dogs, as well as limiting confinement and euthanasia. After being asked to simplify the previous Ethotest © version [13] by many shelter operators and veterinarians, the authors aimed at analyzing the effectiveness of an improved model to test dogs’ behavioral aptitude matching the expectations of a hypothetical adopter. The new version improves the test feasibility by the elimination of a previous computer-based program, and by the introduction of new items such as hierarchical behavior towards food. In this study dogs housed in the sanitary shelter of L’Aquila (Abruzzo, Italy), of different age and sex, either sterilized or not, and belonging to different breeds or crossbreeds, were tested. All the dogs adopted from the shelter were monitored for one year after the adoption by both phone interviews and home visit. The study aimed at analyzing if the shelter dogs showed a good and consistent behavior after adoption in the new environment. The results demonstrated that apart from a predictable relinquishment and an unfortunate case of abuse, none of the dogs adopted showed any unwanted behaviors such as house soiling, jumping up, separation-related and aggressive behaviors; this made their stay in the family a desirable, exciting experience independently of the dog sex, age, and the family composition. The authors stress the necessity of every shelter, together with the veterinary cares, for a professional expert at dogs’ behavior who can efficaciously prevent behavioral problems, eventually train the dogs and afford the pairing with humans in a competent, qualified manner.
Self-attribution of responsibility: consumers of organic foods in a certified street market in Rio de Janeiro, Brazil
Portilho,Fátima;
Etnográfica , 2010,
Abstract: this study aims to contribute to the analyses of consumption, and food consumption in particular, as a political act, by emphasizing the process of self-attribution of responsibility by consumers involved in organic food consumption at an organic certified street market in rio de janeiro, brazil. conducted from the perspective of sociological and anthropological consumption theories, in addition to risk sociology and the theory of reflexive modernization, this study concluded that these consumers act and participate socially through ?responsible consumption? instead of the collective forms of political participation through institutionalized social movements. even though there is a diversity of values and practices, these consumers seem to have in common (1) a mistrust in other social agents and (2) the trust in the importance and effectiveness of their actions.
Consumo sustentável: limites e possibilidades de ambientaliza??o e politiza??o das práticas de consumo
Portilho, Fátima;
Cadernos EBAPE.BR , 2005, DOI: 10.1590/S1679-39512005000300005
Abstract: the recent perception of environmental impact of modern consumption patterns and the centrality of this discourse inside the mainstream of western environmentalism is explained by two discursive "shifts". we will analyse the promises and pitfalls of green consumption proposals and the constraints and possibilities of changing current consumption patterns through the sustainable consumption politics strategies. the present work aims to discuss the following question: which possibilities to enlarge or to inhibit the participation on public domain does emerge with the shift of environmental politics towards the consumption field. instead of restating the consumer alienation, manipulation and heteronomy, or supporting at once their power and freedom of choice, we chose to stress the dialog of contemporary social theory which accepts the possibility of new ways of political action by the articulation of public and private domains. thus, the environment and consumption debate can be done not only in a public but also private arena, comprehending topics from both domains. through this debate, the environmental issue can be placed where private concerns and public issues get together.
Page 1 /4119
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.