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Search Results: 1 - 10 of 14679 matches for " Raquel Fernandes Pupo;Modé "
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Fotodegrada??o de fenol e clorofenóis por processo foto-Fenton mediado por ferrioxalato
Nogueira, Raquel Fernandes Pupo;Modé, Daniela Fonseca;
Eclética Química , 2002, DOI: 10.1590/S0100-46702002000200015
Abstract: the influence of some operational parameters such as stirring the solution during solar irradiation and the solution flow rate into artificial irradiation photoreactor were evaluated on the photodegradation of 2-chlorophenol (2cp) and 2,4-diclorophenol (dcp) by photo-fenton process mediated by ferrioxalate. after evaluation of these parameters, the systems were applied to photodegradation of phenol and mono (2-chlorophenol and 4-clorophenol), di (2,4-dichlorophenol) and tri (2,4,6-trichlorophenol) chlorophenols to evaluate the photodegradation efficiency of these compounds under solar as well as artificial irradiation. small differences in the percentages of total organic carbon (toc) removal and generation of chloride ions were observed with and without stirring the solution during solar irradiation of 2cp. under artificial irradiation, the increase of flow rate resulted in lower toc removal, while a higher rate of toc removal was obtained due to a shorter irradiation time. an intermediate flow rate of 33.4 ml min-1 was then used. under solar irradiation, 15 minutes irradiation were necessary for complete removal of all chlorophenols, however, the complete removal of phenol was achieved in 20 minutes. under artificial irradiation, the chlorophenols were removed between 4.5 and 6.5 minutes of irradiation. the degradation rates increased slightly with the increase of the number of chlorides bonded to the aromatic ring under solar as well as artificial irradiation.
Utiliza??o de rea??es foto-Fenton na preven??o de contamina??es agrícolas
Trovó, Alam Gustavo;Dalla Villa, Ricardo;Nogueira, Raquel Fernandes Pupo;
Química Nova , 2005, DOI: 10.1590/S0100-40422005000500023
Abstract: in this work the application of the photo-fenton process for the treatment of washing water of herbicide containers using solar energy was studied. the influence of the h2o2 concentration and the iron source on the degradation of tebuthiuron and diuron was investigated. the degradation efficiency was strongly affected by the iron source. using ferrioxalate, total mineralization of diuron and tebuthiuron was obtained either for the individual compounds or for a mixture containing both herbicides, while when using fe(no3)3, the maximum mineralization reached for both herbicides was only 50%.
Utiliza o de rea es foto-Fenton na preven o de contamina es agrícolas
Trovó Alam Gustavo,Dalla Villa Ricardo,Nogueira Raquel Fernandes Pupo
Química Nova , 2005,
Abstract: In this work the application of the photo-Fenton process for the treatment of washing water of herbicide containers using solar energy was studied. The influence of the H2O2 concentration and the iron source on the degradation of tebuthiuron and diuron was investigated. The degradation efficiency was strongly affected by the iron source. Using ferrioxalate, total mineralization of diuron and tebuthiuron was obtained either for the individual compounds or for a mixture containing both herbicides, while when using Fe(NO3)3, the maximum mineralization reached for both herbicides was only 50%.
Degrada??o de fármacos residuais por processos oxidativos avan?ados
Melo, Silene Alessandra Santos;Trovó, Alam Gustavo;Bautitz, Ivonete Rossi;Nogueira, Raquel Fernandes Pupo;
Química Nova , 2009, DOI: 10.1590/S0100-40422009000100034
Abstract: the concern about aquatic ecosystems and the potential risk of drinking water contamination by pharmaceuticals have stimulated the study of processes for the efficient degradation of these contaminants, since the conventional treatment have been inefficient on that purpose. the advanced oxidation processes (aops) appear as viable alternatives due to their efficiency on the degradation of different classes of organic contaminants. this review presents an overview of the main aop (o3, h2o2/uv, tio2/uv, fenton and photo-fenton) which have been applied to the degradation of different pharmaceuticals. the main results obtained, intermediates identified and toxicity data are presented.
Diesel degradation in soil by fenton process
Villa, Ricardo D.;Trovó, Alam G.;Nogueira, Raquel F. Pupo;
Journal of the Brazilian Chemical Society , 2010, DOI: 10.1590/S0103-50532010000600019
Abstract: this work reports the use of fenton process for diesel degradation and addresses common aspects of real situations that can affect the soil remediation efficiency. it was observed that most of diesel hydrocarbons containing less than 14 carbon atoms were lost by volatilization prior to the treatment. about 80% degradation was achieved in a loam soil, while less than 20% was observed in a clay loam soil. the multiple additions of h2o2 resulted in 80% diesel degradation, while only 14% of diesel was degraded after a reaction time of 80 h using a single addition. the addition of soluble iron was essential to achieve high degradation levels. no significant increase in diesel degradation (t-test; p = 0.05) was observed using h2o2 dosages between 0.09 and 0.36 g g-1. furthermore, the highest h2o2 dosage applied (0.36 g g-1) degraded around 87% of the organic matter originally present in the soil.
Comentário sobre a revis o "DDT: toxicidade e contamina o"
Nogueira Raquel F. Pupo,Torres Jo?o Paulo Machado
Química Nova , 2003,
Abstract:
Avalia??o da composi??o química de sedimentos do Rio Barigüi na regi?o metropolitana de Curitiba
Froehner, Sandro;Martins, Raquel Fernandes;
Química Nova , 2008, DOI: 10.1590/S0100-40422008000800020
Abstract: sediment samples from the barigui river in curitiba, south of brazil, were evaluated following granulometric composition, organic carbon content, nitrogen, phosphorus and metals such as zinc, lead, chrome, nickel and cadmium. the sediments shown high percentage of phosphorus and nitrogen. also the elemental organic c:n:p exceed the redfield ratios possible because the large amount of sewage input into river. the presence of metals is also high, however the metal cadmium has not been found. but the other metals are in greater concentrations and possibly the presence of these metals is given by industrial and domestic sewage.
Avalia??o do destino e bioacumula??o de benzo(a)pireno através de simula??o computacional
Froehner, Sandro;Martins, Raquel Fernandes;
Química Nova , 2008, DOI: 10.1590/S0100-40422008000500028
Abstract: the objective of this work was to evaluate the environmental distribution of benzo(a)pirene, a polycyclic aromatic hydrocarbon, by the eqc model. the modeling of the contaminant distribution was accomplished by means of the fugacity model applied to a hypothetical scenario constituted by air, water, soil and sediment. the modeling and simulations revealed that the soil is the preferential compartment. we also discuss the implications of the results about fate and ecological risks associated with benzo(a)pirene. we concluded that the emissions of hpas can not be ignored and bioaccumulation among others risks can be induced.
The modular class of a Poisson map
Raquel Caseiro,Rui Loja Fernandes
Mathematics , 2011,
Abstract: We introduce the modular class of a Poisson map. We look at several examples and we use the modular classes of Poisson maps to study the behavior of the modular class of a Poisson manifold under different kinds of reduction. We also discuss their symplectic groupoid version, which lives in groupoid cohomology.
High birth weight is a risk factor of dental caries increment during adolescence in Sweden  [PDF]
Annika Julihn, Ulrika Molund, Emma Drevs?ter, Thomas Modéer
Open Journal of Stomatology (OJST) , 2013, DOI: 10.4236/ojst.2013.39A007
Abstract:

This study aimed to assess whether birth weight is associated with dental caries during the teenage period. In this register-based cohort study, all children of 13 yrs of age (n = 18,142) who resided in the county of Stockholm, Sweden, in 2000 were included. The cohort was followed until individuals were 19 yrs of age. Information regarding dental caries was collected from the Public Health Care Administration in Stockholm. Data concerning prenatal and perinatal factors and parental socio-demographic determinants were collected from the Swedish Medical Birth Register and National Registers at Statistics Sweden. The final logistic regression model showed that birth weight (≥4000 g), adjusted for potential confounders, was significantly associated with caries increment (DMFT ≥ 1) between 13 and 19 yrs of age (OR: 1.29, 95% CI = 1.13 - 1.48). The relatively enhanced risk OR was further increased from 1.29 to 1.52 in sub- jects with birth weight (≥4600 g). On the contrary, subjects with birth weight (<2500 g) exhibited a sig- nificantly lower risk (OR: 0.67, 95% CI = 0.50 - 0.89) for exhibiting caries experience (DMFT ≥4) at 19 yrs of age. In conclusion, birth weight can be regarded as a predictor for dental caries and birth weight (≥4000 g) is especially a risk factor for caries increment during adolescence. 

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