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An overview of the properties of carbon nanotubes is presented as a function of the structural characteristics and of the method of synthesis of these novel advanced materials. Emphasis is given to the catalytic decomposition of hydrocarbons over metal-supported catalysts and also the role of the support in obtaining homogeneous carbon nanotubes in high yelds is discussed. Some potential and real applications of carbon nanotubes are presented in a perspective view.

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The identification and characterization of the hydrochemistry of the groundwaters has been done for seven wells. The sampling occurred during three bimonthly campaigns. The results classified the waters as of the calcium bicarbonated type for the majority of the samples, except for one well, whose composition is of the sodium bicarbonated type. The major ions found and how they determine the quality parameters are consistent with the reactions of mineral dissolution of the majority of volcanic rocks and the reactions with intrusion of alkaline rock in only one well. Anomalous values of nitrate in some wells alert to the impact of especially polluting sources at the time the reservoirs of the hydroeletric plant were formed.

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This study was developed with a soil contaminated by heavy metals, with the purpose of evaluating the action of silicon and phosphorus as protection agents through simple extractions by DTPA. The collected samples were prepared and incubated with five doses of silicon and five doses of phosphorus, with four replicates, amounting to 100 experimental units. After 30 and 60 days, samples of each treatment were collected, submitted to pH analyses and simple extraction by DTPA. The amounts of DTPA-extracted metals depended on the doses of silicon and phosphorus and on the pH. Treatments with silicon and phosphorus was efficient in decreasing the availability of heavy metals in soil.

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Quimica Nova and the Journal of the Brazilian Chemical Society are two examples of successful initiatives taken by the Brazilian Chemical Society (SBQ - Sociedade Brasileira de Química), and may serve as models for the scientific societies of developing countries. Pillars of the SBQ, these two periodicals are undeniable demonstrations that idealism, utopia and dignity are the essential ingredients for transforming dreams into reality. Few believed that the Brazilian chemical community would one day have, as it does today, two scientific research periodicals indexed in the principal international data banks.

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Wet and dry (dust) deposition was measured in the Serra dos Órgãos National Park. VWM pH was 5.3. Non-sea-salt (nss) SO4(2-) comprised 97% of total SO4(2-). The molar ratio [2(nss-SO4(2-)) + NO3-]/[NH4+ + H+] was 1.1, suggesting that pH is predominantly controlled by H2SO4, HNO3, and NH3. Wet deposition of NH4+, NO3-, and nss-SO4(2-) was respectively 0.59, 0.25, and 0.30 kmol ha-1 yr-1. Assuming that dry deposition of N can comprise 30-50% of its total (dry + wet) deposition, the latter is estimated to be 1.2-1.7 kmol ha-1 yr-1 (17-24 kg N ha-1 yr-1).

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This paper discusses of the use of the Impact Factor in the evaluation of chemistry graduate courses by CAPES and the internationalization of the Journal of the Brazilian Chemical Society and Química Nova.

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Se lleva a cabo un análisis de todos los factores que influyen en el desarrollo del área de ingeniería gráfica en la UPC. Se identifican tres etapas historicas: una primera correspondiente a la docencia basada en el uso de herramientas tradicionales, ajustada básicamente a los planes de 1964 y 1972; una segunda correspondiente a la introducción de las primeras herramientas CAD, identificada en los planes de 1992 y 1995; y una última etapa donde los nuevos planes de estudio implementan los conceptos teóricos del EEES, y extiende el uso de CAD paramétrico en la docencia, correspondiente principalmente a los nuevos planes de estudios 2009-10.

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In front of a moment of change in the education, with the entry into force of the LOE (Ley Orgánica de Educación, 2006), the aim of thisarticle is to face the challenge of trying to answer to the need to make concrete learning agreements with the new curriculum based on competences.The present article arises from the interest of being able to offer an approach that facilitates the exposition to show the didactic units from the areaof physical education in relation with the pedagogic principles of the LOE. Departing from this commitment, let’s sense beforehand an offer of thecontributions of the Physical Education to the Basic Competence to learn to learn which entails to develop some capacities in fuction of knowing todo skills

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This survey determined the physical and chemical properties of the gravel place where urban sludge from Rio Descoberto's Water Treatment Plant is disposed. Physical, chemical and biological analysis of the soil samples (n=54), sludge samples (n=2), chemical coagulant (n=20) and samples from superficial waters (n=9) and water table (n=60) were performed. As results we can emphasize the horizontal distribution of mineral phases like gibbsite, organic material, exchanged Ca, available Mn and P on the soils are originated from the sludge. Some of these mobile elements could stimulate the growing of the vegetation, but they also could contaminate the water table.

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Brazilian scientific production in Biochemistry is growing impressively fast, and Rio Grande do Sul is outstanding in that context. This study aims to outline the state's scientific research profile, given its prominent position in the national scenario. Hence, researchers, laboratories, development of human resources and investments by Foundation for the Support to Research in the State of Rio Grande do Sul (FAPERGS) were identified and mapped. We observed that amount of financial support by FAPERGS decreases in last years. Therefore, there is the necessity to reestablish some of FAPERGS's programs, as well as to increase financial support to Biochemistry departments.

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This paper analyses the scientific contribution of chemists and of the Brazilian Chemical Society (SBQ) and its publications to the development of Oceanography in Brazil, as well as major drivers of this participation. A total of 528 articles were analyzed. Most articles (72%) originated in research groups not associated with graduate programs in oceanography. Nearly 50% dealt with the contamination of the marine environment, followed by chemical process studies (32%) and analytical methods development (15%). SBQ journals contributed with 78 articles (14.7% of the total), and rank 1st (QN) and 2nd (JBCS) among scientific journals publishing the analyzed articles.

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Lead metallurgy at Adrianópolis is the largest environmental problem of Paraná, Brazil. The objective of this study was to determine Pb and Zn levels in water and sediment in two catchments by different extraction methods. The high levels of lead in water in most of samples do not allow the human use. Total Pb concentration as high as 795.3 µg L-1 was observed in Ribeira River bank, in a pluvial water stream flowering from a abandoned factory. Due to the high Pb levels in sediments from some sites (maximum of 24,300 mg kg-1) is recommended to avoid the water turbulence.

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In this paper we built three co-authorship networks displaying the acquaintances between countries, universities and authors that have published papers in Quimica Nova from 1995 to 2008. Our research was conducted applying a bibliometric approach to 1782 papers and over 4200 authors. Centrality measures were used and the most significant actors of each network were pointed out. The results using the centrality metrics and the network structures indicated that Quimica Nova resembles a typical scientific community.