Eniz Conceição Oliveira

Application of SPME in pre-concentration of chlorinated phenolic compounds from cellulose bleaching effluents

This paper describes the application of SPME to the analysis of chlorinated organic compounds (CPCs) from a pulp mill effluent. A PDMS fiber was used for SPME and the methodology was developed with 18 CPC standards which had previously been derivatized with acetic anhydride. The compounds were analyzed by GC/MS in the SIM mode, with a detection limit in the range of 0.1 to 2 ppb. Nine CPCs were identified in the effluent, with concentrations varying from 0.9 to 4.8 ppb. The major constituent found in the sample was 2,4,6-Trichlorophenol.

Estudo da adição de resíduo (lodo) de gemas na massa cerâmica vermelha

This work aims to incorporate gems waste (sludge saw cutting of gems), produced in an amethyst and agate firm cut, in the red ceramic body used for the production of solid bricks. The raw materials were tested by X-ray fluorescence, X-ray diffraction and granulometric distribution analysis, for characterize the mineralogy and physical chemistry of materials. Samples were prepared with 0%, 5%, 9%, 13% and 17% waste added to the ceramic body by mass. The physical properties studied were compressive strength, linear shrinkage, water absorption and density in accordance with current technical standard. The results showed that it is possible to incorporate up to 5% of waste in bulk ceramics.

Avaliação da incorporação de resíduo de gemas na massa cerâmica vermelha: um estudo de caso

Over the last few years there is a growing concern about the use of nonrenewable natural resources as well as with the generation of wastes from different sectors. Fortunately, its possible to reuse wastes, for instance, as additives in ceramic industry. The objective of this study is to evaluate the technical feasibility of incorporating the cutting gems waste in the manufacture of bricks, comparing to other work in the same county. One hundred fifty specimens were produced with 0%, 2%, 6%, 10% and 14% waste added to the ceramic mass. The results obtained after testing water absorption, homogeneity, density and compression strength revealed that it is possible to incorporate up to 2% of the residue of such waste in bulk ceramics.

Physicochemical Evaluation of Solid Dosage Forms for Refreshment of Different Brands and Flavors

Os preparados solidos para refresco sao utilizados na elaboracao de bebidas nao alcoolicas atraves de sua diluicao em agua, simulando o sabor de fruta natural. Possuem um preco de mercado mais acessivel que as bebidas prontas para o consumo, p orem, alguns parâmetros ainda nao estao normatizados pela legislacao brasileira. Desta forma, este trabalho traz o resultado de analises fisico-quimicas de cinco diferentes marcas de preparados solidos para refresco e sua relacao com os valores encontrados no referencial cientifico e na legislacao brasileira. Os parâmetros avaliados foram: acidulantes, atividade de agua (a w ), corantes artificiais , potencial hidrogenionico ( pH), sodio e solidos soluveis totais (°Brix) . Os resultados para o sodio foram comparados com os valores declarados nos rotulos das amostras, excedendo o valor em algumas marcas. Os teores de acidulantes variaram de 3,1 a 16,6 % e a atividade de agua entre 0,390 e 0,451. Em relacao aos resultados obtidos para os corantes artificiais, as marcas A, B e D apresentaram resultados acima do limite permitido (1 mg.100 mL -1 ) para o corante Eritrosina. Desta forma, verificou-se que apenas em relacao ao teor de corantes artificiais, nas marcas A, B e D ha resultados que nao estao em conformidade com o que preconiza a legislacao brasileira, sendo que para os demais parâmetros nao ha limites estabelecidos por lei.

CONTRIBUIÇÕES DA ECONOMIA PARA A ALFABETIZAÇÃO CIENTÍFICA: UMA PROPOSTA PARA A EDUCAÇÃO BÁSICA

Science is a part of our everyday life and knowing science has become a necessary condition for a efficiently social participation in decision-making processes. It is imperative that science education guarantees scientific literacy for students and presents scientific knowledge as one of the possibilities of the real interpretation, while also considerating other forms of knowledge in reading the world. Thus, it is proposed a discussion about scientific literacy and its importance in science education, establishing relations between economy, technology, society and environment. The teacher needs to develop a dialogical attitude in his classes, promoting debates, bringing also daily life situations/problems, so that the student can participate with his own ideas. It is concluded that the science teaching should not only be restricted to the transmission of knowledge, it must establish relations between theory and practice, In a CTS (Science, Technology and Society) perspective and the environment to achieve scientific literacy. It is also important to emphasize that the introduction of the economy in basic education can contribute to scientific literacy through the interdisciplinary nature of science, preparing well informed people about the socio-economic reality, which reflects in the indicators of education quality and the country’s economic development.

DETERMINAÇÃO DE ÁCIDO CÍTRICO E pH EM DIFERENTES CULTIVARES DE LIMÃO E MARCAS DE SUCOS ARTIFICIAIS DE LIMÃO EM PÓ

A citricultura possui um importante papel socioeconomico e, ainda, os citros sao de grande importância na alimentacao humana. Dentre eles, podem ser citados os limoes que sao cultivados desde a antiguidade, principalmente por possuirem propriedades medicinais e valor nutritivo. Com o aumento da industrializacao, a busca por praticidade e facilidade na alimentacao proporcionou o crescimento no consumo de produtos como sucos artificiais, que possuem poucos nutrientes e diversos aditivos, contribuindo para o desenvolvimento de problemas como erosao dental causada pelo baixo pH e alergias. Estudos recentes demonstram que o consumo de bebidas citricas, sendo elas naturais ou artificiais, ocasiona uma queda expressiva no pH salivar, que se encontra em contato com o esmalte dentario, o qual possui certo grau de tolerância a acidez, levando o consumidor das mesmas a ter problemas como erosao dental e futuramente possiveis caries. Este trabalho teve como objetivo avaliar o pH e acidez de tres cultivares de limao e tres marcas de sucos artificiais em po de limao. As analises de pH foram realizadas com pHmetro digital e as analises de acidez foram realizadas pela tecnica de titulometria com NaOH 0,1 M. Nos sucos artificiais o pH variou de 2,66 a 2,95 e nos limoes variou de 2,69 a 3,03. Ja a acidez para os sucos artificiais ficou entre 13,87% e 26,32% e para os limoes 2,70% a 6,64%. Portanto, conclui-se que todas as amostras, independentemente de sua origem, podem contribuir para o desenvolvimento da erosao dental, principalmente se houver contato de longa duracao.

TECHNOLOGICAL RESOURCES AND TRANSVERSAL THEMES IN THE TEACHING OF PHYSICS: A CASE STUDY AT THE IFSUL / CAMAQUÃ CAMPUS

It stands out that computers and educational software may be tools for the teaching and learning processes. In the face of that, this research aims to analyze the potentials of computer simulators in the teaching and learning processes through a transversal approach on the theme of Glasshouse Effect. The activity was developed with a class of students from the 2nd year of the Industrial Automation Technical Course – Integrated form, for the subject of Physics II at the Federal Institute for Education, Science and Technology in Rio Grande do Sul IFSul/Camaqua Campus. The proposal adopted as a basis the presumptions of a qualitative research with exploratory bias and methodological outlining of a case study. The results are discussed in the light of Ausubel’s significance learning theory. It is possible to highlight that there has been a significant evolution in students’ knowledge of the theme covered. Thus, it can be assumed that the Physics Education Technology (PhET) simulator has potential to aid in the teaching and learning process.

Análise da Qualidade da Água de Poços Artesianos do Município de Imigrante, Vale do Taquari/RS

Um dos maiores desafios enfrentados pelas presentes e futuras geracoes e encontrar formas de preservacao das fontes de agua, livres de contaminacoes e adequadas ao consumo da populacao. Essa dificuldade esta relacionada a contaminacao dos lencois freaticos devido a ocupacao e uso do solo pela sociedade, alterando os processos fisicos, quimicos e biologicos dos sistemas naturais, causando inumeras doencas e muitas vezes levando a morte. O presente trabalho objetivou avaliar a qualidade da agua das principais fontes naturais do municipio de Imigrante, localizado no Vale do Taquari-RS a fim de averiguar a potabilidade das aguas consumidas pelas comunidades do municipio. Na presente pesquisa foram selecionados dez pocos para a verificacao das caracteristicas fisico-quimicas e biologicas, tais como: pH, condutividade, solidos suspensos, turbidez, oxigenio dissolvido, carbono orgânico, carbono total, carbono inorgânico, nitrogenio, dureza media, temperatura, condutividade e analise microbiologica, comparando os resultados com os padroes preestabelecidos pela legislacao vigente. Dos dez pocos analisados, seis apresentaram-se fora dos parâmetros estabelecidos pela legislacao.

VITAMIN C CONTENT OF STRAWBERRIES EVALUATION OF DIFFERENT CULTIVARS IN DIFFERENT CROPPING SYSTEMS IN BOM PRINCÍPIO /RS

The strawberry is a pseudo much appreciated for its taste, aroma and nutritional properties, containing important source of vitamin C. This vitamin is essential for human health, and its consumption is associated with reduced risk of several diseases. This article aims to assess the vitamin C content in strawberries, analyzing the influence of the Festival and San Andreas cultivars in conventional and organic farming systems, substrate, in Bom Pricipio, Rio Grande do Sul. The vitamin C content was assessed by high performance liquid chromatography in comparison to a standard curve. Vitamin C content found in the Festival and San Andreas cultivars were higher than in the conventional system with respect to the organic system, i.e., 34.85 and 69.31 mg/100 g at step 100 16.62 and 42.19 mg/100 g, respectively.

QUALIDADE DAS ÁGUAS EM ÁREAS URBANAS DO RIO TAQUARI NOS MUNICÍPIOS DE ESTRELA E LAJEADO – RS

A agua e parte integrante do meio ambiente, no entanto, a forma como esta sendo empregada nao condiz com o essencial e necessario para o alcance da sustentabilidade. Desta forma, estabeleceu-se uma investigacao buscando verificar a qualidade da agua do rio Taquari, vazante entre os municipios de Lajeado e Estrela no Rio Grande do Sul, com o objetivo de contribuir, com os dados levantados pelo comite de bacia da regiao, poder publico e pela coletividade.