Irving langmuir: o milagre da ciência

Irving Langmuir received the Nobel Prize in Chemistry in 1932 "...for his outstanding discoveries and investigations within the field of surface chemistry", according to the Swedish Academy. However, few people know that his work comprises other very important contributions, and not only for chemistry, such as the discovery of plasma, the atomic hydrogen, the pure thermoionic phenomenon, the development of the cloud seeding technique for weather modification, among many others. This paper summarizes Langmuir's most important discoveries and theories, with an especial mention for his practical inventions and his work on the atomic theory.

A história da ciência e o objeto de seu estudo: confrontos entre a ciência periférica, a ciência central e a ciência marginal

The historiography of science has undergone a profound change from the traditional perspective of a few decades ago, according to which only mainstream science was worth pursuing as a research field. Such a restricted outlook was not conducive to a thorough understanding of the whole process of the construction of science. New approaches have breathed new life into the discipline, taking into account not only scientific endeavours from so-called peripheral societies, but also from different quarters within or close to the central groups. From this a new and far more interesting view has emerged, showing a complex and richer texture.

Natureza do coque formado sobre a mordenita durante a transalquilação de benzeno

Zeolite catalysts have been extensively used in petroleum refining and the chemical industry although they are deactivated by coke deposition. In order to find the best condition to avoid deactivation, the coke formation on H-mordenite was studied in this work. The coke was produced during benzene transalkylation with C9+ aromatics, under several reaction conditions. It was found that hydrogenated coke was produced in all samples without affecting the selectivity of toluene and xylene formation. This is explained in terms of the mordenite structure and the presence of hydrogen.

A natureza pedagógica da experimentação: uma pesquisa na licenciatura em química

In this paper we discuss the characteristics of experimental activities described by teachers and students in a teaching credentials course in Chemistry. The research pointed out a set of characteristics that seem to favor the learning process: the bringing up of the student's knowledge; the mediation by peers; the dialogue to set out the student's knowledge; the debate; the validation of arguments; the discussion about the context. The authors argument that, because of the empirical view of Science present in Chemistry courses, the discussion about the nature of Science is important.

O Quadrante de Ruetsap e a anti-ciência, tecnologia e inovação

The concept of research and the controversy among classical models for C, T & I, outdated by the development of knowledge and Post-modern society needs were revisited through the (3) Quadrants advanced by Donald Stokes in the mid-nineties. The scientific community to fit into these Quadrants was faced with many difficulties and reacted by issuing pseudo-facts, accepted by under-prepared technocrats as viable justifications for conducting research in face of these new paradigms. In a poor country full of contrast and needs such as Brazil, this attitude satisfies the bureaucracy and academic elite, but frustrates government and society, that do not get, in the expected measure, the benefits of their commitment with the Teaching, Research and Extension Sectors mainly embedded in the Public University system. An extension, in fact a contradictory approach, to Pasteur's Quadrant, is proposed to characterize this situation: The Syndrome of Ruetsap's Quadrant.

A importância do observatório de atividades industriais vis-à-vis tendências em ciência, tecnologia e inovação

Given that innovation is fundamental for competitiveness, and that it is intrinsically linked to knowledge, it has become essential to foster effective interaction between the Brazilian productive sector and universities and R&D centers. This interface should be created by means of the model used in developed countries: Observatory of Industrial Activities and Trends in Science, Technology and Innovation. The present work describes its main functions, using examples of activities undertaken by the Chemical Industry Information System of the Federal University of Rio de Janeiro related to production systems of primary and high-tech industries, examining the diffusion of knowledge to decision-makers.

A aplicação da fotoquímica inorgânica nas diversas áreas da ciência

This article provides an overview of the current status of research involving the photochemical behavior of transition metal complexes in the following important areas: medicine, biology and materials science including some of the experiences of the writer. Coverage is selective, generally focusing on highlights and the most recent developments, with the broad aim of showing the interdisciplinary field of inorganic photochemistry.

Raios-x: fascinação, medo e ciência

This work presents the discovery and the use of x-rays at the end of the XIXth and the beginning of the XXth century. X-rays greatly impacted science and everyday life. Their existence broke the idea that knowledge had reached a limiting step. In general, people regarded x-rays as a marvel of science, but reactions against their use were also found. Several applications were proposed, especially in medicine. However, little or no attention was paid to security measures, leading to health damages and even death. The development of the radiological protection took into account the accidents with the x-rays.

Ciência como cultura: paradigmas e implicações epistemológicas na educação científica escolar

"Science as culture" is based on the assumption that science is a valuable component of human culture. We therefore have to build the bridge, in cultural terms, from the scientific community to the common citizen. Teaching science as culture requires the co-construction of knowledge and citizenship. Ways of articulating science/technology with society are invoked, pondering on the ethical ambivalence of such connections. The goals of this reflection are to think about: a) epistemological obstacles that, in favouring the logic of monoculture, oppose the implantation of the science as culture; b) epistemological strategies that point towards a diversity of cultural practices and "constellations" of knowledge leading to the reconfiguration of the being through knowledge; c) imperatives that force us to (re)think the epistemological bases suited to the paradigmatic changes and which translate the dynamics and complexity of the evolution of the frameworks that currently sustain science and school scientific education.

Artigos da revista Ciência Hoje como recurso didático no ensino de química

This paper presents the results from the selection and analysis of Ciência Hoje articles published from 2004 to 2009 with the aim to discuss some of their features which can assist teachers in chemistry teaching. Therefore, the articles were analyzed according to their content and format based on an analytical tool proposed by Kawamura and colleagues. The results indicate that this magazine offers a reasonable collection of articles related to chemistry with a variety of contents and approaches.

Ações de divulgação de química na Casa da Descoberta - centro de divulgação de ciência da Universidade Federal Fluminense

This paper describes the main activities regarding scientific dissemination in the field of Chemistry at Casa da Descoberta (CD) - a Scientific Dissemination Center of the Fluminense Federal University. It presents a brief history of CD and discusses the difficulties concerning the dissemination of Chemistry at Scientific Dissemination Centers. This work also approaches some activities developed throughout the years: experiments performed in relation to the visitors' daily life, training of monitors to act as mediators in the non-formal teaching of Chemistry, production of dissemination materials, elaboration of books, as well as activities that relate formal to non-formal education.