Fluxos de CO2 do solo na Floresta Nacional de Caxiuanã, Pará, durante o experimento ESECAFLOR/LBA

O experimento ESECAFLOR/LBA foi conduzido na Floresta Nacional de Caxiuanã, Pará, e este artigo procura investigar os efeitos do estresse hídrico sobre a respiração do solo. Duas parcelas de 1 hectare foram instaladas em janeiro de 2002. Uma parcela (A) permaneceu em condições naturais e foi usada como controle, enquanto que na parcela de exclusão (B) foram instalados painéis plásticos para que aproximadamente 70% da precipitação fosse excluída. Os dados foram coletados mensalmente de janeiro a dezembro de 2005. Durante o ano de 2005 houve 2.211,6 mm de precipitação na ECFPn, ou seja 9,96% acima da média de 2.011,2 mm. As médias da umidade do solo foram de 15,6±9,2 e 9,5±3,4% nas parcelas A e B, respectivamente. As médias da temperatura do solo para as parcelas A e B foram de 25,6±0,4 e 25,7±0,5 ºC, respectivamente. As médias dos fluxos de CO₂ no solo nas parcelas A e B foram de 3,46±0,44 e 3,21±0,84 μmolCO₂ m^-2s^-1, respectivamente. Com a exclusão de parte da chuva na parcela B, houve uma redução de 7,23% nos fluxos de CO₂ no solo (0,25 μmolCO₂ m^-2s^-1), 39,1% na umidade do solo (6,1p.p.), e um aumento de 0,39% na temperatura do solo (0,1ºC). A umidade do solo na parcela B foi menor do que na parcela A, devido ao sistema de exclusão da chuva, no entanto no início do ano, devido a reformas que o mesmo passou esses valores estiveram próximos.

O experimento investigativo e representações de alunos de ensino médio: obstáculos epistemológicos em questão

Este trabalho teve por finalidade explorar o potencial teórico-metodológico de uma atividade investigativa como recurso didático para o processo de construção e validação de hipóteses. Objetivou-se, também, analisar as interpretações discursivas - representações - produzidas pelos alunos quando se deparam com fenômeno(s) que não consegue(m) explicar, ou explicam utilizando argumentos distorcidos do ponto de vista científico. Nesta perspectiva, as representações dos alunos foram discutidas tendo em conta a presença de obstáculos epistemológicos bachelardianos. Os resultados mostram que nessas representações aparecem os obstáculos animistas e realistas, os quais podem dificultar a compreensão dos conceitos científicos por parte dos alunos. Apenas ocasionalmente aparece o obstáculo verbalista, relacionado com o uso de uma linguagem comum para explicar certo conceito científico. O obstáculo substancialista também se faz presente por meio da “propriedade substancial” responsável por algumas distorções conceituais produzidas pelos alunos.

Uma abordagem diferente na estatística do experimento Millikan

The classic Millikan experiment to determine the electron charge is very interesting from the point of view of statistics of experimental measurements. In a physics laboratory it is suggested to divide the obtained values of the electric charge by the value of an electron charge, and it is possible to experimentally establish that the oil droplets carry integer numbers of electrons. This work presents a new statistical algorithm for the treatment of measurements and for determining the best value of the electron charge in a Millikan experiment.

O experimento e o lúdico: reflexões sobre atividades didáticas experimentais para o ensino de Física e a ludicidade

In this work, is discussed the importance of experimental activities in Education of Physics in Basic Education from the experience of Supervised Stage and the work with the Initiation of Teaching in the Program PIBID CAPES, in this case linked to the Department of Education of the Institute of Biosciences, Campus Rio Claro, São Paulo State, in partnership with three schools of basic education in the city. At first, based on the work of Ferreira with Instrumentation for Teaching Physics, consider the electrostatic theme. The focus is the searching for equipments constructed with low cost materials and easy access. Were developed and promoted strategies of the use of such materials in Physics’ Teaching, with a view to reintroducing experimental teaching activities in Public Basic Education, in the form Workshop Learning and Teaching of Physics, as well as lessons of Laboratory with the help of script and also in the form of an Experiments Library. These experimental activities were critically analyzed with a focus on playfulness. The focus of work in experimental activities for the Physics’ Teaching allowed to redeem, critically, didactic materials. From the standpoint of playfulness, playful moments and interaction of individuals with the knowledge that provides the experimental material when used strategically, they seem to be of great relevance to the Physics’ Teaching in Basic Education. It is possible to use experiments in Physics’ Teaching in public schools

Elaboração de um material didático aplicado ao ensino de física para utilização do experimento virtual da dupla fenda

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Física Moderna no Ensino Médio: um experimento para abordar o efeito fotoelétrico

Considering the importance of the inclusion of Modern and Contemporary Physics in the curriculum of Physics in High School, it is proposed in this work an experimental activity, made with low- cost materials, which presents the photoelectric effect. This activity can be used articulating this phenomenon with some technological applications experienced by the students in their daily lives. When working the experiment, the teacher can encourage students to investigate what happens during its execution and, through questions, get them to express their ideas in the previous attempt to explain its operation. This articulation linked to social interaction in the classroom can arouse the students’curiosity and motivation of students to learn the subject taught in classroom.

Guerra e o desenvolvimento científico: uma superaula interdisciplinar e investigativa construída em torno de um experimento central

This research presents the description of the assembly, development and execution of an experiment and of an interdisciplinary and student research activity built by some undergraduates from Biological Sciences, Physics, Mathematics and Chemistry PIBID subprojects of the Faculty of Science, FC - UNESP, Bauru/SP Campus. These subprojects are part of a single interdisciplinary group, which has as its main activity the Superclass, which consists of an intervention of the PIBID members during the class schedule, with an interdisciplinary and student research didactic sequence, applied by four groups of ten members, in two local State Schools. The experiment treated in this assignment was a miniature cannon (minicannon), and it was used in a Superclass that had the War and Science Development as its theme, wherein the knowledge of all areas were built from the analysis of the multiple variables involved on the cannon shots. These variables were surveyed with the students through the experiment research, during the Superclass, being focused on three of them: the shot and the explosives; the trajectory; and the target. The experiment was extremely successful, because it could instigate the students, who were interested, questioning and debaters for several times during the class. The minicannon made possible the interdisciplinary and the student research work among the four areas of science involved. Despite it has been a laborious experiment in its construction, it has proven to be innovative, and its use has transformed the students‟ ingenuous curiosity into epistemological curiosity, a key factor in the construction of scientific knowledge, wherein the dialogue established in the Superclass explored this new curiosity

Emissão de gases do efeito estufa e estoque de carbono no sistema solo-planta em área com aplicação superficial de calcário e gesso em experimento de longa duração

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Experimento de física controlado remotamente: uma avaliação sobre processo de ensino e de aprendizagem

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Qualidade física e química do solo em função do sistema de produção e da aplicação superficial de silicato e calcário em experimento de longa duração

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Aplicação de projeto de experimento no processo de manufatura de uma bobina de alumínio

TProducts must follow specifications in order to attend demands requested. In terms of rolled aluminum, one of the most significant items for customers is coil thickness. This is because only a tiny variation in thickness might cause a serious problem on customer's manufacturing line. Thereby, this research aims to analyze through design of experiments which factors and how they affect the thickness of aluminum coils. The response variable of the experiment is the thickness of aluminum coil, tensile strenght and yield strenght are the factors of the experiment and trimmers machines were considered as blocking. Data were obtained through tensile tests. The result of the experiment states that, according to the analysis of variance (ANOVA), while there is significant difference between the two levels of tensile strength, there is not any difference between the two levels of yield strength and trimmers machines. The thickness of the aluminum coils with high values of tensile strength tends to be thicker when compared with low values of tensile strength

Pulsar da Medusa: um experimento de criação cênica e estudo da expressividade do corpo-voz a partir dos fatores do movimento de Rudolf Laban

Pós-graduação em Artes - IA

Aplicação de projeto de experimento no processo de manufatura de uma bobina de alumínio

TProducts must follow specifications in order to attend demands requested. In terms of rolled aluminum, one of the most significant items for customers is coil thickness. This is because only a tiny variation in thickness might cause a serious problem on customer's manufacturing line. Thereby, this research aims to analyze through design of experiments which factors and how they affect the thickness of aluminum coils. The response variable of the experiment is the thickness of aluminum coil, tensile strenght and yield strenght are the factors of the experiment and trimmers machines were considered as blocking. Data were obtained through tensile tests. The result of the experiment states that, according to the analysis of variance (ANOVA), while there is significant difference between the two levels of tensile strength, there is not any difference between the two levels of yield strength and trimmers machines. The thickness of the aluminum coils with high values of tensile strength tends to be thicker when compared with low values of tensile strength