Institution
National Nuclear Energy Commission
Government•Rio de Janeiro, Brazil•
About: National Nuclear Energy Commission is a government organization based out in Rio de Janeiro, Brazil. It is known for research contribution in the topics: Dosimetry & Laser. The organization has 3816 authors who have published 4694 publications receiving 59951 citations.
Topics: Dosimetry, Laser, Neutron, Corrosion, Monte Carlo method
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the concentration of As, Ba, Cr, Cu, Pb, Sb and Zn were determined by INAA and XRF in surface soil samples from 7 public parks located within Sao Paulo city.
Abstract: There has been little research on metal concentration levels in urban soils of Sao Paulo, a city with 19 million inhabitants with severe pollution problems. In the present study, the concentration of As, Ba, Cr, Cu, Pb, Sb and Zn, were determined by INAA and XRF in surface soil samples from 7 public parks located within Sao Paulo city. The results obtained showed that soils of Sao Paulo public parks present concentration levels of the studied elements higher than the reference values for soils in Sao Paulo State. Traffic related elements such as Cu, Pb and Zn presented high concentrations in parks located near avenues of highly dense traffic and may be associated to vehicular sources.
33 citations
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TL;DR: The analysis of the results in terms of Hansen and Flory-Huggins solubility parameters evidenced the influence of dipolar interactions and hydrogen bonding on the dispersibility of oxidized SWNTs.
Abstract: Surface composition plays an important role in carbon nanotube dispersibility in different environments. Indeed, it determines the choice of dispersion medium. In this paper the effect of oxidation on the dispersion of HiPCO single-walled carbon nanotubes (SWNTs) in N-methyl-pyrrolidinone (NMP), N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMA), N-dodecyl-pyrrolidinone (N12P) and cyclohexyl-pyrrolidinone (CHP) was systematically studied. During the oxidation process, similar amounts of carboxylic acid and phenolic groups were introduced to mostly already existing defects. For each solvent the dispersion limits and the absorption coefficients were estimated by optical absorption analysis over a range of SWNT concentrations. The presence of acid oxygenated groups increased SWNT dispersibility in NMP, DMF and DMA, but decreased in N12P and CHP. The absorption coefficients, however, decreased for all solvents after oxidation, reflecting the weakening of the effective transition dipole of the ??? transition with even limited extension functionalization and solvent interaction. The analysis of the results in terms of Hansen and Flory?Huggins solubility parameters evidenced the influence of dipolar interactions and hydrogen bonding on the dispersibility of oxidized SWNTs.
33 citations
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TL;DR: Results are presented of the element concentrations, daily dietary intakes and contributions to the total daily intake of essential elements in 30 food groups of a Market Basket of Sao Paulo State, Brazil, which shows dietary habits of a large-scale population.
33 citations
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TL;DR: An in vitro model of bioluminescent Candida albicans biofilm inside curved dental root canals showed APDT showed to be an effective way to inactivate C. albican biofilm inactivation.
Abstract: Antimicrobial photodynamic therapy (APDT) combined with endodontic treatment has been recognized as an alternative approach to complement conventional root canal disinfection methods on bacterial biofilms. We developed an in vitro model of bioluminescent Candida albicans biofilm inside curved dental root canals and investigated the microbial reduction produced when different light delivery methods are employed. Each light delivery method was evaluated in respect to the light distribution provided inside curved root canals. After conventional endodontic preparation, teeth were sterilized before canals were contaminated by a bioluminescent strain of C. albicans (CEC789). Methylene blue (90 μM) was introduced into the canals and then irradiated (λ = 660 nm, P = 100 mW, beam diameter = 2 mm) with laser tip either in contact with pulp chamber or within the canal using an optical diffuser fiber. Light distribution was evaluated by CCD camera, and microbial reduction was monitored through bioluminescence imaging. Our findings demonstrated that the bioluminescent C. albicans biofilm model had good reproducibility and uniformity. Light distribution in dental tissue was markedly dependent on the light delivery system, and this strategy was directly related to microbial destruction. Both light delivery systems performed significant fungal inactivation. However, when irradiation was performed with optical diffuser fiber, microbial burden reduction was nearly 100 times more effective. Bioluminescence is an interesting real-time analysis to endodontic C. albicans biofilm inactivation. APDT showed to be an effective way to inactivate C. albicans biofilms. Diffuser fibers provided optimized light distribution inside curved root canals and significantly increased APDT efficiency.
33 citations
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TL;DR: In this article, rare earth/c electrocatalysts (Pt, Ce, Pr, Nd, Sm, Tb, Dy, Ho and Er) were prepared by an alcohol reduction process using ethylene glycol as reduction agent and solvent and Vulcan XC72 as support.
33 citations
Authors
Showing all 3838 results
Name | H-index | Papers | Citations |
---|---|---|---|
Giorgio Parisi | 108 | 941 | 60746 |
Sergio Ferrara | 105 | 726 | 44507 |
Richard Wilson | 70 | 809 | 21477 |
Eliana B. Souto | 66 | 447 | 15706 |
Andrea Saltelli | 65 | 184 | 31540 |
Fausto Croce | 51 | 162 | 11753 |
Sílvia M. Rocha | 42 | 163 | 4934 |
Marcos Duarte | 41 | 122 | 5855 |
Luiz Gustavo Cançado | 41 | 106 | 13155 |
Ruggero Caminiti | 41 | 267 | 7296 |
Francesco Romanelli | 40 | 236 | 5756 |
Mario Molinaro | 39 | 111 | 5923 |
Giovanna Cenacchi | 38 | 217 | 4948 |
Claudio Pellegrini | 38 | 235 | 5885 |
Maria Manuela Silva | 37 | 324 | 5258 |