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Bericht zur Sommerakademie Informatik: IT is your turn girls: Vorbereitung und Durchführung der zweiten "Sommerakademie Informatik: IT is your turn girls" zur Förderung der Studierneigung junger Frauen im IT-Bereich an der TU ChemnitzEckardt, Ines January 2010 (has links)
Mit den Projekt Sommerakademie Informatik: IT is your turn girls soll die Attraktivität der IT- Studienfächer bei Studieninteressentinnen gesteigert werden. Dabei steht eine geschlechtersensible Organisationsentwicklung insbesondere im Bereich der Studienwerbung und Außendarstellung im Mittelpunkt. Bei der Konzeption der zweiten Sommerakademie Informatik: IT is your turn girls haben wir uns neben sozialwissenschaftlichen Erkenntnissen aus der Geschlechterforschung auch auf die Forschungsergebnisse zur Sommerakademie Informatik 2009 bezogen, um die Auswirkung struktureller Prozesse zu minimieren. Der vorliegende Projektbericht erläutert die Planung und Umsetzung nach den Richtlinien des Konzeptes sowie die Besprechung der Ergebnisse aus der Teilnehmerinnenbefragung vor und nach der Sommerakademie Informatik: IT is your turn girls 2010.
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Certain about uncertainty / What students need to know about measurement uncertainties to compare data sets.Kok, Karel Willem 07 July 2022 (has links)
Messunsicherheiten sind ein wesentlicher Bestandteil eines Messergebnisses. Das Thema wird jedoch oft vernachlässigt in der Sekundarstufe, und die Schüler*innen haben viel Schwierigkeiten mit Varianz in Datensätzen. Diese Arbeit berichtet über die Gestaltung und Evaluierung einer digitalen Lernumgebung (DLE). Die konzeptbasierte DLE nutzt ein etabliertes Sachstrukturmodell für die Sekundarstufe und besteht aus drei Teilen: Einführung in und Grundlagen von Messunsicherheiten, Berechnung und Bedeutung des Mittelwerts und der Unsicherheit sowie dem Vergleich von Messergebnissen. Die Wirkung wurde in einem Prä-Post-Design getestet. Der Prä- und Posttest umfasste zwei Prüfungsaufgaben: einen Kompetenztest und ein Datenvergleichsproblem, bei dem eine mit Begründung versehene Entscheidung getroffen werden musste. Die Teilnehmenden wurden nach dem Zufallsprinzip einer der drei Gruppen A, B oder C zugeteilt und bekamen einen, zwei oder alle drei Teile der DLE gezeigt. Insgesamt nahmen 154 Schüler*innen der Klassenstufen 8 bis 11 freiwillig und selbstständig teil.
Diese Studie hat gezeigt, dass mit zunehmendem konzeptionellen Wissen die Fähigkeit der Schüler*innen, Datensätze zu vergleichen, deutlich zunimmt. Der konzeptbasierte DLE kan selbstständig von Schüler*innen in 60 Min. bearbeitet werden.
Das Kodiermanual ermöglicht eine schnelle Analyse der Begründungen der Schüler*innen im Rahmen von Datenvergleichsproblemen. Dieses Manual kann leicht in der Schule eingesetzt werden. Diese Codes zeigen in einem feinkörnigen Detail die Qualität und Entwicklung der Fähigkeit der Schüler*innen, Datensätze zu vergleichen.
Es wurden keine Korrelationen zwischen der Klassenstufe und dem Ergebnis des Kompetenztests oder der Begründungsqualität gefunden. Der Erfolg der DLE und das gleichzeitige Fehlen eines solchen Zusammenhangs bedeutet, dass das Thema Messunsicherheiten bereits in der achten Klasse eingeführt werden kann. / Measurement uncertainties are an essential part of a measurement result. The topic is, however, rarely addressed in secondary education and students struggle a lot with variance in data sets. This thesis reports on the design and evaluation of a Digital Learning Environment (DLE). The concept-based DLE uses an established subject matter model for secondary education and consists of three parts: introduction to and underpinnings of measurement uncertainties, calculation and meaning of the mean value and the uncertainty, and the comparison of measurement results. The effect was tested in a pre-post design. The pre and post-test consisted of two probes: a competency test and a data comparison problem where a decision had to be made supported by a justification. Participants were randomly assigned one of three groups A, B, or C and were shown one, two, or all three parts of the DLE. A total of 154 students of grades 8-11 participated voluntarily and independently.
This work has shown that with increased conceptual knowledge, students' ability to compare data sets increases significantly. The concept-based teaching can be done by having students work independently with the DLE in 60 min.
The coding manual allows for a quick analysis of students' justifications in the context of data comparison problems. This coding manual can be easily used in school settings. These codes show, in a fine-grained detail, the quality and development of students' ability to compare data sets.
No correlations have been found between grade level and competency test score or justification quality. The success of the DLE and the simultaneous absence of any such correlation means that the topic of measurement uncertainties can be introduced as early as eighth grade.
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Physical Computing als Mittel der wissenschaftlichen Erkenntnisgewinnung / in der Informatik und als fächerverbindende MINT-ArbeitsweiseSchulz, Sandra 17 December 2018 (has links)
Physical-Computing-Geräten wie Robotern und Mikrocontrollern wird eine wichtige Rolle
als Lernmedium für Schülerinnen und Schüler zugesprochen. Zu lernende Kontexte sind
ähnlich vielfältig wie die inzwischen existierenden Geräte. Die Komplexität der Systeme ist
mannigfaltig und bisherige Forschung geht zumeist von dem Gerät als Forschungsgegenstand
aus. Im Rahmen dieser Dissertation wird von einem geräteunabhängigen Physical-
Computing-Prozess als Problemlöseprozess ausgegangen, um ein Fundament für nachhaltige
und geräteunabhängige Forschung zu schaffen sowie Physical Computing als Unterrichtsgegenstand zu beschreiben. Aufgrund von Merkmalen, wie der Arbeit mit Sensorik
und Aktuatorik sowie dem iterativen Testen und Evaluieren, scheint Physical Computing
Ähnlichkeiten zu dem naturwissenschaftlichen Experiment aufzuweisen. Dieser Zusammenhang und die potentiellen Auswirkungen auf die Informatikdidaktik werden in den
folgenden drei Ausprägungsformen untersucht.
Basierend auf Modellen aus der Literatur wird ein Modell des Physical-Computing-
Prozesses abgeleitet und mithilfe empirischer Studien adaptiert. Bei dem Vergleich der
Prozesse der wissenschaftlichen Erkenntnisgewinnung und des Physical Computing können
diverse Gemeinsamkeiten festgestellt werden. Insbesondere verlaufen die Prozesse parallel
zueinander, was die Grundlage für einen MINT-Problemlöseprozess bildet.
Bislang wurden konkrete Probleme von Schülerinnen und Schülern bei der Interaktion mit
den Geräten peripher beschrieben. In dieser Arbeit wird eine Analyse von Problemursachen
vorgenommen und auftretende Probleme werden kategorisiert. Probleme, die gleichzeitig
mehrere Problemursachen haben, werden aufgedeckt und eine Problemtaxonomie zur Beschreibung von Problemursachen abgeleitet.
Ein mehrstufiges Feedback-Modell zur Unterstützung des Problemlösens in Physical-
Computing-Aktivitäten wird basierend auf der Problemtaxonomie entwickelt. Durch eine
empirische Untersuchung wird es als unterstützend für den Physical-Computing-Prozess
evaluiert und bildet damit ein Modell zur Entwicklung von kognitiven Tutorensystemen
für Physical Computing. / Physical computing devices like robots and microcontrollers play an important role as
learning devices for students. These devices as well as the learning contexts are multifaceted.
The complexities of the systems are diverse and the existing research is usually
concentrated on the devices. This thesis develops as a starting point a device-independent
physical computing process by seeing it as problem-solving process. The goal is to construct
a base for sustained and device-independent physical computing research and to
describe physical computing as a school subject. The physical computing process seems
to share similarities with the scientific inquiry process, because of characteristics like working
with sensors and actuators and iterativ testing and evaluating. This relation and the
implications on computer science education are explored in the following three facets.
Based on existing literature, a model of the physical computing process is derived and
supplemented by empirical data. In the comparison of the scientific inquiry and the physical
computing processes substantial commonalities are identified. Hence, a base for a joint
STEM problem-solving process is built.
So far, concrete students’ problems during the activities with physical computing devices
are described as a side product. In this thesis problem sources are uncovered and occurring
problems categorized. Problems having more than one problem source are uncovered and
a problem taxonomy is derived from that.
Based on the problem taxonomy, a multilevel feedback model to support problem solving
during physical computing activities is developed. With an empirical exploration, the taxonomy
is evaluated. Results indicate that the taxonomy is supportive for achieving the
physical computing process. Finally a model for a cognitive tutoring system for physical
computing is outlined.
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Minting America coinage and the contestation of American identity, 1775-1800 /Ambuske, James Patrick. January 2006 (has links)
Thesis (M.A.)--Miami University, Dept. of History, 2006. / Title from first page of PDF document. Includes bibliographical references (p. 59-64).
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HIS – an international and digital summer school for STEM students / HIS - Internationale und digitale MINT-Summer SchoolBergert, Aline, Helbig, Jana, Nenner, Christin 26 August 2016 (has links) (PDF)
The teaching project HIS (Holistic International STEMs – Learning with case studies and real life industry experiences) is presented as part of the poster session.
Experience shows that German (outgoing) and international (incoming) students have difficulties to communicate properly at the workplace in Germany as well as abroad due to language differences, especially in STEM terms. In addition, young professionals often do not have experience in working in international or virtual teams. All those challenges are current job requirements, not just in global companies. But: How to teach this in higher education? The classical formats of lectures or seminars are not suitable. Therefore, there is a need to develop and prove new teaching formats, within the curriculum as well as extracurricular.
With focus on STEM subjects the presented project combines three current impacts on higher education: Internationalization, digitalization, and labor market orientation.
The concept of the project is that STEM students from different countries will attend an international, virtual summer school (April to June 2016). They solve real-life job case studies together in small interdisciplinary teams. The participants are mentored by national and international industry partners and STEM professors. With such, the participants will improve language and communication skills, and apply and exchange their expertise as well as gain intercultural work experience.
The concept was awarded by the “Stifterverband für die deutsche Wissenschaft” (Donors association for the promotion of humanities and sciences in Germany).
The poster introduces the project and exemplary the three-dimensional assignments of one case study (occupational, lingual, and intercultural). At present, the project should be handled as a “project in progress”.
Keywords: technology, teaching projects, STEM, internationalization, digitalization, labor market orientation, employability, job orientation, competencies, development of new curricula
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Moeda no Brasil no final do século XVII / Money in Brazil in the late seventeenth centuryCoelho, Rafael da Silva 13 March 2014 (has links)
O estudo da moeda contribui para a compreensão da dinâmica do Antigo Sistema Colonial. Entre Portugal e Brasil, no seiscentos, ocorria uma evasão monetária em virtude, sobretudo, das vantagens comerciais fundadas no exclusivo metropolitano. Esta evasão foi agravada pela lei de 4 de agosto de 1688, que determinava um aumento de 20% no valor extrínseco das moedas portuguesas e que as patacas espanholas deveriam correr a peso pela razão de 100 réis a oitava. O objetivo da lei era combater o cerceio e evitar a evasão monetária na metrópole. Entretanto, no Brasil, cujo meio circulante era composto predominantemente por patacas cerceadas, houve resistências, insatisfações e até motins contra a implementação da lei, que diminuiria o valor extrínseco do dinheiro dos moradores na colônia. O governador-geral Câmara Coutinho publicou e fez cumprir a lei, o que intensificou ainda mais o escoamento de moedas do Brasil para Portugal, acentuando ainda mais as dificuldades dos senhores de engenho e lavradores, num momento crítico da produção açucareira. Quando a escassez de dinheiro comprometeu a arrecadação, ordenou-se a fundação da Casa da Moeda na Bahia para produção de moedas provinciais. / The study of currency contributes to the understanding of the dynamics of the Old Colonial System. Between Portugal and Brazil in the seventeenth century, there was a evasion of coins due mainly to commercial advantages based on metropolitan exclusive. This evasion was intensified by the law of August 4th, 1688, which determined an increase of 20% in the extrinsic value of the Portuguese coins, and that the Spanish patacas should run by the weight ratio of 100 reis by one eighth. The purpose of the law was to combat the curtailment and prevent the evasion of coins in the metropolis. However, in Brazil, whose currency was composed predominantly by curtailed patacas, there were resistances, dissatisfaction and even riots against the implementation of the law, which would decrease the extrinsic value of the money of the residents in the colony. The general governor Câmara Coutinho published and did comply with the law, which further intensified the flow of coins from Brazil to Portugal, further accentuating the difficulties of the senhores de engenho and lavradores, at a critical moment in sugar production. When the money shortage undertook the tax collection, it was ordered the founding of the Mint in Bahia for the production of provincial coins.
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Virtual. International. Job orientated. – Best practice on how virtual collaboration courses can succeedNenner, Christin, Bergert, Aline, Naa Amlah Böhnisch, Angelina 06 June 2018 (has links) (PDF)
From April to June 2016 a new and exclusively virtual teaching format – the international STEM1 Summer School – was provided at the University of Mining and Technology in Freiberg. The paper presents the approach, didactical design, and results of evaluation.
The international STEM Summer School was developed and tested within the project „Holistic International STEMs - Learning with case studies and real-life industry experiences“. The aim was to better prepare STEM students for challenges in the current professional world that are characterized by in-ternationalization and digitalization. The project offers some ideas on how to teach the currently re-quired skills and competencies by industry in higher education. The conceptualization of the project was made possible with funding from the Donors\' Association for the Promotion of Humanities and Sciences in Germany2.
The exclusively virtual collaboration is due to the different geographical distances and locations of the participating students, which generates specific challenges. On the one hand, technical conditions at the particular places of residence have an impact on virtual collaboration. On the other hand, cultural, lingual, and occupational differences, as well as the differing media literacy, play an important role. In addition, the setting of objectives and provision of incentives is decisive for the shared virtual work. The results of the first round of the international STEM Summer School indicate possible solution strategies based on the three areas of media use, interaction, and task orientation.
During the Summer School, students from ten different countries solved real-life job case studies in small interdisciplinary teams. The exchange took place with the help of various e-learning tools like the virtual classroom, wiki, forum and e-portfolio. The participants were mentored by national and international industry partners, STEM professors, and e-tutors. After nine weeks work in intercultural teams they presented their results and learning outcomes during a web conference.
The following article focusses on the evaluation results as well as selected insights and challenges.
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Viabilidade agroeconômica da hortelã (Mentha piperita L.) em dois cultivos sob doses de jitirana e épocas de colheita. / Agroeconomic viability of mint (Mentha piperita L.) in two crops under jitirana doses and harvesting times.ALMEIDA, Alany Moisa Bezerra de. 25 May 2018 (has links)
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Previous issue date: 2016-11-29 / A hortelã é uma planta bastante utilizada como planta medicinal e alimentícia, sendo
produzida por agricultores em sistema familiar de produção. Dois experimentos foram
conduzidos na Fazenda Experimental Rafael Fernandes, no distrito de Alagoinha, zona
rural de Mossoró-RN, com o objetivo de avaliar o cultivo orgânico da hortelã sob
diferentes doses de jitirana e épocas de colheita. O primeiro experimento foi conduzido
no período de 13/08/2015 a 09/12/2015, e o segundo no período de 09/11/2015 a
10/12/2015, no delineamento experimental de blocos completos casualizados com os
tratamentos arranjados em esquema fatorial 4 x 3, com três repetições. O primeiro fator
foi constituído por quatro doses de jitirana (0,0; 0,5; 1,0 e 1,5 kg m-2 de canteiro em
base seca) e o segundo fator, correspondendo a três épocas de colheita (30; 60 e 90 dias
após o transplantio). Para a cultura da hortelã utilizou-se a cultivar “Mentha piperita”.
As características avaliadas foram as seguintes: altura da biomassa, produção de
biomassa, número de molhos, massa seca, teor e rendimento de óleo. Alguns
indicadores econômicos foram observados, tais como: custo de produção, renda bruta,
renda líquida, taxa de retorno e índice de lucratividade. Houve interação entre os
fatores-tratamentos para o primeiro cultivo (produção, número de molhos e teor de óleo)
e na rebrota da hortelã, nas características (rendimento e teor de óleo). No primeiro
cultivo, houve acréscimo no número de molhos de hortelã em função dos fatorestratamentos
com valores máximos de 1300; 3503 e 2651 unidades/100m2 nas épocas
30;60 e 90 dias, correspondendo as doses 1,3; 0,2 e 0,2 kg/m2, respectivamente. Na
rebrota apresentou número médio de molhos de 2805 unidades/100 m2 (30 dias) e 2542
unidades/100 m2 (60 dias). A dose de 0 kg m2 de jitirana na época de colheita de 60 dias
em primeiro cultivo, proporcionou rentabilidade liquida de R$ 3.458,00, taxa de retorno
da ordem de R$ 3,26 e índice de lucratividade de 69,3%. Para a rebrota ocorreu
rentabilidade liquida de R$ 2.753,00, taxa de retorno de 2,80 e índice de lucratividade
de 64,2% na dose de 0 kg m-2 e época de colheita de 30 dias. A produção de hortelã em
sistema orgânico de produção constitui-se em alternativa para o produtor. / The plant consortium presents itself as one of the most appropriate methods to the
practice of horticulture, in agroecological molds with numerous advantages in the
environmental aspect, productive and economical. Two experiments were conducted at
the Experimental Farm Rafael Fernandes in Alagoinha district, a rural area of Mossoró-
RN, in order to assess the agricultural economic viability of mint consortium with
coriander fertilized with manure jitirana more beef. The first experiment was conducted
in the period from 08.11.2015 to 11.05.2015 and the second experiment in the period
from 11.27.2015 to 22.03.2016, in a randomized complete block with treatments
arranged in a 2x4 factorial design with three replications. The first factor consisted of
monocropping and intercropping mint and coriander, and the second factor was the
different doses of jitirana mixed with manure (0.0, 1.0, 2.0 and 3.0 kg m- 2 site). For
mint culture was used to cultivate "Mentha piperita". For the coriander was used to
cultivate "Verdão". The characteristics evaluated for the Mint culture were as follows:
height of biomass, fresh weight, number of sauces, dry mass, oil content and yield. For
the coriander crop the following characteristics were evaluated: plant height, number of
stems plant-1, productivity, number of sauces and dry mass. Also economic indicators
were used, such as land equivalent ratio (LER), cost of production, gross income, net
income, rate of return and profitability index. The use of more manure jitirana cattle
contributed to the increase of the productive characteristics of the consortium in the two
growing seasons, with number of mint sauces 17.6 and 5.8 in 3.0 doses and 2.2 kg m-2
respectively. For coriander crop, the values were 16.5 and 15.3 m2 sauces in 3.0 kg dose
m-2, respectively. The equivalent area obtained in the two experiments were 1.72 and
1.78, respectively. The greater economic efficiency of the consortium was observed in
the first growing season with the application of 3.0 kg m-2 of more manure jitirana cattle
in an area of 100 m2, with gross income of R $ 3,761.00; net income of R $ 2,727.50;
return rate of R $ 3.64 and 72.52% profitability index.
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Moeda no Brasil no final do século XVII / Money in Brazil in the late seventeenth centuryRafael da Silva Coelho 13 March 2014 (has links)
O estudo da moeda contribui para a compreensão da dinâmica do Antigo Sistema Colonial. Entre Portugal e Brasil, no seiscentos, ocorria uma evasão monetária em virtude, sobretudo, das vantagens comerciais fundadas no exclusivo metropolitano. Esta evasão foi agravada pela lei de 4 de agosto de 1688, que determinava um aumento de 20% no valor extrínseco das moedas portuguesas e que as patacas espanholas deveriam correr a peso pela razão de 100 réis a oitava. O objetivo da lei era combater o cerceio e evitar a evasão monetária na metrópole. Entretanto, no Brasil, cujo meio circulante era composto predominantemente por patacas cerceadas, houve resistências, insatisfações e até motins contra a implementação da lei, que diminuiria o valor extrínseco do dinheiro dos moradores na colônia. O governador-geral Câmara Coutinho publicou e fez cumprir a lei, o que intensificou ainda mais o escoamento de moedas do Brasil para Portugal, acentuando ainda mais as dificuldades dos senhores de engenho e lavradores, num momento crítico da produção açucareira. Quando a escassez de dinheiro comprometeu a arrecadação, ordenou-se a fundação da Casa da Moeda na Bahia para produção de moedas provinciais. / The study of currency contributes to the understanding of the dynamics of the Old Colonial System. Between Portugal and Brazil in the seventeenth century, there was a evasion of coins due mainly to commercial advantages based on metropolitan exclusive. This evasion was intensified by the law of August 4th, 1688, which determined an increase of 20% in the extrinsic value of the Portuguese coins, and that the Spanish patacas should run by the weight ratio of 100 reis by one eighth. The purpose of the law was to combat the curtailment and prevent the evasion of coins in the metropolis. However, in Brazil, whose currency was composed predominantly by curtailed patacas, there were resistances, dissatisfaction and even riots against the implementation of the law, which would decrease the extrinsic value of the money of the residents in the colony. The general governor Câmara Coutinho published and did comply with the law, which further intensified the flow of coins from Brazil to Portugal, further accentuating the difficulties of the senhores de engenho and lavradores, at a critical moment in sugar production. When the money shortage undertook the tax collection, it was ordered the founding of the Mint in Bahia for the production of provincial coins.
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Análise da estabilidade termo-oxidativa do biodiesel de soja na presença de antioxidantes naturais obtidos por diferentes técnicas de extração / Analysis of the thermo-oxidative stability of soybean biodiesel in the presence of natural antioxidants obtained by different extraction techniquesSantos, Ana Claudia Cabral dos 05 December 2014 (has links)
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Previous issue date: 2014-12-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Biodiesel is a fuel that can be obtained from renewable sources and due to its chemical composition is sensitive to oxidation. To increase their oxidative stability is necessary to add antioxidants, which are compounds capable of avoiding or delaying oxidation reactions and can be synthetic or natural, from the natural, we highlight a variety of plants with antioxidant activity, among them the mint (Mentha spicata L.) and Acerola (Malpighia glabra L.). The objective of this study was to evaluate the oxidative stability of biodiesel in the presence of natural antioxidants from extracts of Acerola and mint leaves obtained by conventional extraction and supercritical CO2 on temperature and various pressure using oxidative stability in Rancimat test, avaliou- is also the synthetic antioxidant TBHQ, to compare the results obtained with the use of the plant extracts. The effects of temperature and pressure on the yield and quality of the extract. The best induction times were obtained for biodiesel plus the supercritical extracts of Acerola 40 °C and 150 bar condition (1.38 h) and 60 °C and 250 bar (1.07 h) and the supercritical extract of mint conditions of 40 °C and 150 bar (1.08 h), 40 °C and 250 bar (1.71 h) and 60 °C and 250 bar (2.04 h) and soxhlet extract with hexane obtained from both acerola (2.84 h) and Mint (2.87 h), which showed greater induction time of the control (1.04 h). Biodiesel plus the synthetic antioxidant TBHQ got time higher induction to control and biodiesel plus extracts and from 36.95 hours. The oxidative stability of biodiesel was more increased when the extracts obtained by conventional extraction using Hexane as the solvent, which can be extracted from a larger quantity of compounds with antioxidant activity. / Biodiesel é um combustível que pode ser obtido de fontes renováveis e devido sua composição química é sensível à oxidação. Para aumentar sua estabilidade oxidativa é necessário acrescentar antioxidantes, que são compostos capazes de evitar ou retardar reações de oxidação e podem ser sintéticos ou naturais, dentre os naturais, destacam-se uma variedade de plantas com atividade antioxidante, dentre elas a Hortelã (Mentha spicata L.) e Acerola (Malpighia glabra L.). O objetivo deste trabalho foi avaliar a estabilidade oxidativa do Biodiesel na presença de antioxidantes naturais dos extratos das folhas de Acerola e Hortelã obtidos por extração convencional e com CO2 supercrítico em condições de temperatura e pressão variadas, utilizando teste de estabilidade oxidativa em Rancimat, avaliou-se, também, o antioxidante sintético TBHQ, para comparar com os resultados obtidos com a utilização dos extratos das plantas. Foram avaliados os efeitos da temperatura e Pressão no rendimento e da qualidade do extrato. Os melhores tempos de indução obtidos foram para o Biodiesel acrescido dos extratos supercríticos da Acerola nas condições 40 °C e 150 bar (1,38 h) e 60 °C e 250 bar (1,07 h) e os extratos supercríticos da Hortelã nas condições de 40 °C e 150 bar (1,08 h), 40 °C e 250 bar (1,71 h) e 60 °C e 250 bar (2,04 h) e os extratos soxhlet obtidos com hexano, tanto da Acerola (2,84 h) quanto da Hortelã (2,87 h), que apresentaram tempo de indução maior que o controle (1,04 h). O Biodiesel acrescido do antioxidante sintético TBHQ obteve tempo de indução superior ao controle e ao biodiesel acrescidos dos extratos, sendo de 36,95 horas. A estabilidade oxidativa do Biodiesel foi superior quando acrescido dos extratos obtidos por extração convencional utilizando Hexano como solvente, que, pode ter extraído uma maior quantidade de compostos com atividade antioxidante.
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