90,063 research outputs found

    Study of alkaline hydrothermal activation of belite cements by thermal analysis

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    The effect of alkaline hydrothermal activation of class-C fly ash belite cement was studied using thermal analysis (TG/DTG) by determining the increase in the combined water during a period of hydration of 180 days. The results were compared with those obtained for a belite cement hydrothermally activated in water. The two belite cements were fabricated via the hydrothermal-calcination route of class-C fly ash in 1 M NaOH solution (FABC-2-N) or demineralised water (FABC-2-W). From the results, the effect of the alkaline hydrothermal activation of belite cement (FABC-2-N) was clearly differentiated, mainly at early ages of hydration, for which the increase in the combined water was markedly higher than that of the belite cement that was hydrothermally activated in water. Important direct quantitative correlations were obtained among physicochemical parameters, such as the combined water, the BET surface area, the volume of nano-pores, and macro structural engineering properties such as the compressive mechanical strength

    How to teach chemistry? Is Chemistry a new universal language

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    Chemistry has been developed greatly throughout the 20th century. Chemistry is included in the curriculum of elementary and secondary education. In general, students are not interested in science, and because of this ,students tend not to make an effort to learn and understand the meaning of concepts and the chemistry language that are being taught to them. If we consider that there is a little bit analogy between chemistry and foreign languages, we should learn the sym bols of the Periodic Table as symbols of an alphabet. The first knowledge that one needs to know when we are learning a second language is the new symbols of our new alphabet. It is necessary to learn more than 103 symbols, the chemical alphabet. After that, the students are ready to begin the formation of chemical words. In this case, learning the compounds names is easier when only two elements are involved, but when there are more than two, the chemical language is more complex. The proposal of this study is intended to design and implement a teaching strategy for teaching and learning the chemical language, first of all the chemical alphabet, the Periodic Table and then, the language which it is built the chemistry. For this proposal, we will use some m ultimedia application (Information and Communication Technologies (ITC)), which consists in an interactive periodic table. Students will be able to push one element and they will be able to see the properties of this element and which other element will be able to combine with it, and furthermore, if this element will be able to combine with itself. When they know properly the simple language, they will be able to continue studying more complex words, in this case, the reactions. With this multimedia application, the students will be able to watch how the atoms will change, one atom changes to a new atom during a whole reaction. And finally, they will be able to watch how these new atoms have new properties, and they combine each one. With this Periodic Table, the students learn chemical formulas and equations. 2. Experimental. This study was created as a descriptive study in which the survey technique was used. The study was carried out during the course 2013 /14. The sample consisted of 35 volunteer studen ts from two different classes, at the first course of Mechanical Engineer degree at University of Málaga. But the vast majority of them were there, they did not love chemistry. Each student made one questionnaire about the utility of our multimedia application. The scale of the test was a five point Likert type scale with a range of five options. The positive items range from 1= Certainly Agree to 5 = Certainly Disagree. 3. Results and Discussion. Mostly the average of these statements showed an overall positive response statements .The majority of the each student average of the response statements shown are positive, more than 2.5. After this study, we studied if there was some difference between the two groups studied and it can be seen that the mean an d the standard deviation for the different variables according to the two investigated groups demonstrated that there was no significant difference in the level of interest or utility that they give to the multimedia application. 4. Conclusions. The results of this study are based on a survey purpose after the use of an interactive application in order to improve the learning process of the chemistry language. This information is valuable since students could watch these animations on a computer. This is based on the cognitive theory of multimedia learning, which assumes that learners process information through a dual coding capability involving a auditory/verbal channel and a visual/pictorial channel. Nevertheless, the vast majority of students recognize that chemistry knowledge is useful to interpret aspect of their everyday life, but not many of them express their wish to continue chemistry studies.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Chemical language, a language that you need to know if you want to learn Chemistry

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    There is a little bit analogy between chemistry and foreign languages. One reason why people find Chemistry as a language is because of the orthography, the systematic way it is written. In order to learn a second language, one needs to know the new symbols, In chemical language, it is necessary to learn 103 symbols, the chemical alphabet, this is the periodic table. After knowing the alphabet, the students are ready to begin the formation of chemical words. In this case, learning the compounds names are easier when only two elements are involved, but when there are more than two, the chemical language is more complex. As a language, students can build a huge amount of chemical formulas and reactions from finite components. After a few classes of chemistry, the students are ready to attempt intelligent conversation by combining the chemical alphabet words into sentences, the reactions. They can translate between Spanish and Chemistry. Actually, every chemist in every language refer to the same concept using the same word. It is true that in a subject as Chemistry, the language is laden with a specific vocabulary. As a foreign language, chemistry demand hard work in the form of many hours of repetitions examples and problems, but why not easy the burden by beginning. Chemical education researches have recognized that students often have difficulty learning chemistry concepts, language and so on. Researchers have proposed several suggestions as to the reasons for this difficulty, including frequent overloading of student working memory [1-3]. One of the major goals in teaching chemical language with a contextual approach is that students will develop the ability to understand a make decision about issued they may face in their everyday lives outside of the classroom [4,5]. In this work, we report a study that employed computer simulations. The proposal of this study is intended to design and implement a teaching strategy for teaching and learning the chemical language, first of all the chemical alphabet,the Periodic Table and then, the language which it is built the chemistry. For this proposal we will use some multimedia application (Information and Communication Technologies (TIC)), which consists in a interactive periodic table. Student will be able to push one element and they will be able to see the properties of this element and which other element will be able to combine with it, and furthermore, if this element will be able to combine with itself. Whenn they know properly the simple language, they will be able to continue studying more complex words, in this case, the reactions. With this multimedia application, the students will be able to watch how the atoms will change, one atom changes to a new atom during a whole reaction. And finally, they will be able to watch how these new atoms have new properties, and they combine each one. [1] Carlson, R., Chandler, P., Sweller, J., J. Educ. Psych., 95, (2003) p. 629. [2]. Johnstone, A. H., Chem. Educ. Res. Pract., 7, (2006) pp 49. [3]. Johnstone, A. H., J. Chem. Educ., 87, (2010) pp 22. [4] King, D. 2007. Teacher beliefs and constraints in implementing a context-based approach in chemistry. Teaching Science- the Journal of the austalian Scinece teacher association, 53 (1), 14.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    The use of simulations and videos in order to improve the learning of REDOX reactions in Engineering Degrees

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    Many students from secondary schools to universities in many countries struggle to learn chemistry and many do not succeed. Many high school and university students experience difficulties with fundamental ideas in chemistry [1]. Despite the importance of the foundation of chemistry, most students emerge from introductory courses with very limited understanding of the subject [2]. Chemistry had been regarded as a difficult subject for students by many researchers, teachers and science educators [3-4] because of the abstract nature of many chemical concepts, teaching styles applied in class, lack of teaching aids and the difficulty of the language of chemistry. Information and communication technologies (ICT) have fundamentally changed the practices and procedures of teaching Chemistry at University Degrees. In general, the use of ICT in education lends itself to more student-centred learning settings. Furthermore, and due to the fact that the globalization is becoming more and more important, the role of ICT in education is becoming more and more essential. The presence of ICT in the interactive educational environment can help to develop thinking skills and make classrooms an environment for educational growth. ICT also helps students to develop new thinking skills which may transfer to different situations which may require analysis and comprehension skills, and consequently critical skill development. ICT has become an increasingly popular technological tool within an educational context. Even though, the potential of ITC use in increasing student interactivity and collaboration has been explored by many educators, the research conducted on the effectiveness of these tools use in an educational context is still quite limited. In this work a study to investigate the use of ICT in the teaching and learning of Chemistry at Malaga University was conducted between 2015/16. The study participants were two classrooms of the 1º level of Mechanical Engineering Degree. In the present work, a positive attitude towards learning has been accompanied by a motivated behaviour. This could be seen as the use of the simulation and some videos (ICT). The present study investigated whether computer assisted instruction, simulation and videos were more effective than face-to-face instruction in increasing student success in chemistry. This study aims to investigate the effectiveness ICT as an educational tool in an undergraduate course for students. The results of the Mechanical Engineering Degree study is based on surveys purpose after the use of an interactive application and videos in order to know, if they think the use of these ITC have improved their learning process. On average, the students find the use and application useful, overall because they are able to transfer from macroscopic level to microscopic or/ and symbolic level. Several concepts and conceptual relations covered in the chemistry or science courses were provided in a concrete way, the help of computer simulations improved the student success significantly. [1] Carson, J. , & Watson, E. M (2002). Undergraduate students’ understandings of entropy and gibbs free energy. University Chemistry Education, 4, 4-12. [2] Ochs, R.S. (1996) Thermodynamics and Spontaneity, Journal of Chemical Education, 73(10), pp 952-954. [3] Carter, C.S. and Brickhouse, M.W. (1989) What Makes Chemistry Difficult? Alternate Perceptions, Journal of Chemical Education, 66(3), 223-225 [4] Nakhleh, M.B. (1992) Why Some Students Don’t Learn Chemistry, Chemical Misconceptions, Journal of Chemical Education, 69(3), 191-196.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Motivation to learn Chemistry in massive open online courses

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    One of the key factors for any educational proposal to achieve success lies in the motivation of students. The disposition that the students have before the learning is fundamental to be able to obtain the objectives. MOOC (Massive Open Online Course) has emerged strongly in the context of university education. The use of MOOC offers time in the classroom that can be used to do active learning activities in which teachers' role is essential, and students can review learning materials at their own pace. The objective of this paper was to evaluate a course about concepts. The use of a MOOC named Introduction to Chemistry: Reactions. It is a course for students with limited background in chemistry; basic concepts involved in chemical reactions, stoichiometry, the periodic table, periodic trends, nomenclature. The evaluation of the proposal was made by students of Electrical Engineers at University of Malaga, with satisfactory results.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Pointless Trips

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    DON’T STOP BELIEVING: AN ARGUMENT AGAINST BUDDHIST SKEPTICISM

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    The Aging of Gametes: The Known and the Unknown

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    Facial emotion recognition: spanish psychometric validation of a NIMSTIM stimuli subset.

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    Treball Final de Grau en Psicologia. Codi: PS1048. Curs: 2018/2019.Facial expressions are used to guide us and make us to understand the experiences that others have towards us, and also to lead our behavior in an adaptive way. Facial expressions have a communicative value as Darwin said, and their interpretation is of interest to researches because of the links between emotional experience and facial expressions (Tottenham et al., 2009). Nowadays, several sets of emotional facial pictures sets are currently available (Adolph & Georg, 2010). However, these pictures sets are anything but uniform and vary extensively in terms of physical characteristics. One of the most used databases is the NimSim set of facial expressions (Tottenham et al., 2009). The purpose of this study is the psychometric validation of a 367 stimuli from the NimStim into the Spanish population for the emotional facial recognition. In this study, 127 students (105 women) participated. The task consisted of the emotional facial recognition of the six basic emotions and one neutral expression. Repeated measures ANOVA showed that type of motion, the type of mouth, and the interaction betweenthem, were statistically significant variables for the emotional facial expressions recognition. The results showed that: a) The Spanish and American population follow the same pattern of emotional facial expressions recognition (happiness is the best recognized emotion, and fear the worst); 2) the type of mouth is an important moderator variable for the facial emotional expressions recognition; and c) there are not significant gender differences in the facial emotional recognition. The results of the present research empirically corroborate the validity of the NimStim for its use in Spanish samples in the affective neuroscientific research, particularly in the emotional facial expressions recognition field.Las expresiones faciales nos sirven para guiarnos y hacernos comprender las experiencias que tienen los demás hacia nosotros, y también para dirigir nuestra conducta de manera adaptativa. Darwin argumentaba que las expresiones faciales tenían un valor comunicativo y la interpretación de éstas es de interés para los investigadores debido a la relación entre la experiencia emocional y las expresiones faciales (Tottenham et al., 2009). Actualmente son varios los conjuntos de imágenes de expresiones faciales emocionales que están disponibles (Adolph & Georg, 2010). Sin embargo, estas bases de datos no son uniformes y varían ampliamente en sus parámetros físicos. Una de las bases de datos más utilizada en la investigación afectiva es el the NimSim set of facial expressions (Tottenham et al., 2009). El propósito de este estudio es la validación psicométrica de un subconjunto de 367 estímulos del NimStim en la población española para el reconocimiento de expresiones faciales emocionales. En este estudio participaron 127 estudiantes (105 mujeres). La tarea consistía en el reconocimiento de la expresión facial de las seis emociones básicas y una neutra. El ANOVA de medidas repetidas mostró que el tipo de emoción, la forma de la boca y, especialmente, la interacción entre ambas, son variables estadísticamente significativas para el reconocimiento de expresiones faciales emocionales. Los resultados mostraron que: a) el patrón de reconocimiento de las distintas emociones obtenido en la muestra española es muy similar al publicado para muestras norteamericanas (la alegría fue la mejor reconocida y el miedo la peor); b) la forma de la boca al expresar una emoción es una importante variable moduladora para el reconocimiento de la expresión faciales emocionales (especialmente, para el miedo y la tristeza); y c) no hay diferencias significativas entre hombres y mujeres a la hora de reconocer expresiones faciales emocionales. Los resultados de la presente investigación corroboran empíricamente la validez del NimStim para su uso en muestras españolas en investigaciones en el ámbito de la neurociencia afectiva, particularmente en el reconocimiento de expresiones faciales emocionales
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