Ethanol, methanol and water extracts representing mostly native plant species found in the Amazon region were prepared, respectively, by maceration, continuous liquid-solid extraction and infusion, followed by evaporation and freeze-drying. The freeze-dried extracts were tested for lethality toward Aedes aegypti larvae at test concentrations of 500 µg / mL. In general, methanol extracts exhibited the greatest larvicidal activity. The following 7 methanol extracts of (the parts of) the indicated plant species were the most active, resulting in 100 % mortality in A. aegypti larvae: Tapura amazonica Poepp. KEY WORDS
Recebido em 14/3/13; aceito em 11/7/13; publicado na web em 9/8/13 SYNTHESIS OF MCM-41 MESOPOROUS MATERIAL USING FRESHWATER SPONGE AS A SOURCE OF SILICA. Fresh water sponge was used as a silica source for the synthesis of MCM-41 via the hydrothermal process. The silica was extracted from the sponge by washing with nitric acid and piranha solution. Synthesis of MCM-41 was performed at 100 °C for 5 days and the procedure was optimized, with modifications made to the leaching temperature of the silica and the synthesis of mesoporous material, which was characterized by XRD, FT-IR, SEM and adsorption of N 2. The optimal result was achieved at a temperature of 135 °C for 3 days, showing ordered mesoporous material with a surface area of 1080 m 2 g -1.
The condemnation of Galileo Galilei, a milestone in the history of science, is interpreted as if the Catholic Church were an oppressive institution and against scientific investigation. However, much of what we are taught is nothing more than myth or legend, such as persecution and condemnation at the bonfire. In fact, far from persecuting him, the Roman Catholic Apostolic Church welcomed Galileo as a son and, moreover, it was the cradle of science and the university system, for being the institution that was most interested in cultivating knowledge, it was also the one that invested most in astronomy. Previously called natural philosophy, modern science was influenced by the priests of the Catholic Church, mainly by the Jesuits who were pioneers in astronomy. Priests like Nicolaus Copernicus, who started the theory of heliocentrism, Roger Boscovich, a Jesuit priest who gave the first coherent description of the atom giving rise to the first modern atomic theories, Gregor Mendel, who was the monk who performed experiments with peas, Georges Lemaître, the Belgian priest who created the Big Bang theory. These and many others made great discoveries that made science take great leaps. Not discarding other civilizations and religions, pantheists, who brought a lot of wisdom, such as the Incas, Mayans, Babylonians, Egyptians, etc., but the Christian Church was the only one that reached to take science to another level, for it was based on the belief of a single God who had created all things with physical order and laws. Therefore, the objective of this work is to contest the idea that the Church is opposed to Science, exposing the difference between the two and aiming at scientific investigations carried out by priests. Concluding that this Christian institution did not persecute science, but made great leaps, did not burn scientists on the bonfire because of their ideas, did not delay science in the medieval and the conflict or divergence is the result of criticism made for the Church by Enlightenment thinkers and the story badly told full of fantasies.
A website or site, also in Portuguese for site or site (“from the Web” or “from the Internet”), is a set of web pages, that is, hypertexts generally accessible via the HTTP protocol on the Internet. The set of all existing public websites makes up the World Wide Web. Pages on a site are organized around a base URL, or site, where the main page resides, and generally reside in the same directory on a server. Pages are organized within the site in a hierarchy observable in the URL, although the hyperlinks between them control how the reader perceives the overall structure, which may have little to do with the hierarchical structure of the site’s files. A website for educational purposes has been used as a tool to support learning. This work aims to report the development and use of a website in the discipline of analytical chemistry at the State University of Ceará-UECE-FAEC. The methodology of the same was through the creation of the Website on the Wixsite platform, with the following email address olacerdajr.wixsite/quimicando. The same was applied in the discipline of Analytical Chemistry II, and the Analytical II of the night shift was not applied, for the purpose of comparison in teaching learning. The class that used the website was evaluated through the production of video lessons, while the class that did not use it was evaluated through traditional evaluations, tests. In addition, the class where the website was applied, a questionnaire was carried out containing the following information: 1) I consider the use of the website relevant in this discipline, 2) the website must be maintained in the next editions of the discipline, 3) The website is easy to use, 4) the instructions contained in the site help to carry out the activities. To quantify the results, at the end of the period, a knowledge test was carried out between classes A and B to compare teaching and learning in relation to the subjects covered during the period of 2016.2 of the discipline of analytical chemistry II. With the application of the website in classes A and B, it was possible to observe that the methodology applied in class A obtained a better teaching and learning response with a percentage of 20% for the first subjects and 10% for the last subjects, demonstrating that teaching learning is best absorbed with class learning and teaching. In general, the results of the evaluations of the website by the students suggest good acceptance and show this as an easy-to-use support tool for face-to-face teaching, which can contribute to teacher/student interaction through mediation in any day and time. Through the comments, the professor, even though he was not at the university, interacted with the students, evaluating their activities, and the students, in turn, had the opportunity to redo the activities, correcting their mistakes and being free to express their points of view. teacher view.
This work deals with a thermodynamic approach to the ideality of gases in a systematic and organized way. Important aspects are presented regarding the understanding of the behavior of gases and their properties, such as the properties of the physical state of matter, in which the gas is in the simplest state according to the arrangement of its molecules. It was highlighted the topics that led the scientists to arrive at the knowledge currently available, through experimental results observed by them, resulting in empirical laws that helped to understand the behavior of the gases in diverse situations, as in the cases of variations of temperature and pressure. These laws, which combined proportionately, resulted in a mathematical equation called the perfect or ideal gas equation, a law that strictly follows the formulated empirical mathematical relations and which is the starting point for the deduction of what is really the ideal or perfect gas. The gas model quoted is the basis of the kinetic theory of gases, which theory has a well-developed theoretical understanding to explain the behavior of an ideal gas. Also exposed in this work is the definition of real gases that present different behavior of the ideal gases due to the interactions that can occur between their molecules. For a better understanding of the real gases we explained ways of studying the intermolecular forces in these gases, such as the compressibility factor and the Van der Waals equation. Also, the transformations occurring in the gaseous state, such as liquefaction, are discussed. The present work was done on the basis of bibliographical research in order to have a favorable knowledge about the study of gases from the thermodynamic point of view, aiming to establish the necessary definitions of the study of the phases of matter.
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