Átomo de Oxigênio (O)

Ilustração componente do jogo “Quimolécula (http://www.loa.sead.ufscar.br/quimolecula.html)” desenvolvido pela equipe do Laboratório de Objetos de Aprendizagem da Universidade Federal de São Carlos (LOA/UFSCar).

Mobilidade urbana sustentável em projetos estruturantes: analise urbanística e ambiental do corredor de transporte da Avenida Bernardo Vieira Natal/RN

The search for a sustainable urban mobility, has recast the public policy of transport and movement for all, in order to contribute to the welfare economic, social and environmental. Within this context, has as its main objective review here in the city of Natal in the state of Rio Grande Norte, the deployment of the new road infrastructure of the transport corridor of Bernardo Vieira Avenue and checking at least with regard to urban areas and environmental chosen here, as will indicators to assess sustainable urban mobility, that the theory has been well constructed, but in practice little way to apply the proposed guidelines for sustainability. To achieve this result, is initially a literature review with the principal investigators of the matter, since the concepts of indicators of sustainable urban mobility. And a second time, participating in to the case study, using the methodology of environmental awareness, through analysis photographs, notes and testimony in the study area ace to reach conclusions

Espaços de pobreza e mobilidade urbana: os deslocamentos da população de baixa renda em Natal/RN

This dissertation is an attempt to understand how families with an income of up to three minimum wages and living in different Areas of Demographic Expansion (AEDs) of Natal municipality specifically in the districts of Igapó and Salinas (North Administrative Zone of the city), Ponta Negra (South Administrative Zone), Santos Reis, Praia do Meio, Areia Preta and Mãe Luíza (East Administrative Zone) and Felipe Camarão (West Administrative Zone) solve their problems of urban mobility. It is, therefore, a reflection upon the mobility needs of poor urban households as expressed in terms of origin-destiny displacements for specific movements (house-work, house-school, house-shopping, house-healthcare and house-leisure), all of which being analyzed within the relationship between public transportation and poverty spaces of the city. In order to develop the study, theoretical aspects and themes related to the production of the urban space, to social and spatial segregation, to urban mobility and to transportation were confronted with the collected data referring to the urban population previously selected. One of the research main findings is the crucial role mobility plays in the social differentiation of such people living in Natal and that any policy for the improvement of their living conditions must take mobility issues into account

Demanda química de oxigênio, clorofila a e comunidade fitoplanctônica como indicadores da qualidade da água no Canal do Pataxó/RN

The current study examined spatial-temporal modifications and water quality through chemical and biotic indicators during both dry (January, February and November 2006) and wet seasons (March to June 2006). This study was carried out in Armando Ribeiro Gonçalves Reservoir, RN, Canal do Pataxó and after the water station treatment (WST). The physical-chemical parameters were measured in situ and inorganic nutrients, chlorophyll a and Free Oxygen Demand (FOD) were analyzed in laboratory conditions. Quali quantitative analyses of phytoplankton were carried out utilizing Sedgwick-Rafter camera. Results indicate that DQO concentrations were low. FOD concentrations in the reservoir were comparatively higher in the dry season (5.21 mgL-1; 5.64 mgL-1 e 6.05 mgL-1) in relation to the wet season (4.52 mgL-1; 4.12 mgL-1 e 4.92 mgL-1), in surface, intermediate and bottom waters, respectively. FOD values were inferior to 1.0mgL-1in both Canal do Pataxó and after WST, which is considered adequate for public use reservoirs. Although FOD concentrations were low, Armando Ribeiro Gonçalves Reservoir, Canal do Pataxó and WST were classified as euthophizied, mesotrophic ad oligotrophic, respectively, considering the Index of Trophic State Criteria. Chlorophyll a concentrations in the study reservoir were higher in the surface (199.2 µgL-1) during the wet season, whereas in Canal do Pataxó concentrations decreased from 1.56 µgL-1 to 0.028 µgL-1, and after WST values were low (0.059 µgL-1). Dominance of cianobacterias, such as Planktotrhix agardhii (dry season) and Microcystis sp (wet season) was registered in all three areas. In the reservoir and Canal do Pataxó, density of cianobacterias, such as P. agardhii and Microcistys sp., was superior to the values allowed by the Health ministry (HM). However, after WST, density values of cianobacteria were inferior to values established by the HM

Estudo da adesão de pinos endodônticos modificados superficialmente por plasma de oxigênio

The work presents the effect of plasma treatment when applied in fibers or carbon/glass posts in the adhesion fiber/resin and posts/cement. This has for objective the modification of the surface of the fibers, as well as the wettability of the posts, seeking the improvement of the adhesion and of the connection fiber/resin in the processing of polymeric composites reinforced with the same ones. 120 posts (Reforpost) were used and 30 meters of fibers of carbon and of glass (Fibrex), of the company Angelus. The samples were divided in three groups of 40 specimens: GROUP I - 20 posts of glass fiber and 20 of carbon without treatment to it shapes, GROUP II -20 posts of glass fiber and 20 of carbon treated to it shapes in the surface and GROUP III - 20 posts of glass fiber and 20 of carbon make with fibers in natura after plasma treatment. The plasma treatment was accomplished with oxygen and with temperature in the camera fixed at 200°C, for one hour of exhibition. The posts and the fibers were characterized before and after the treatment. The wettability was measure by pendent drop method, and interface fiber/resin and posts/cement were observed by optical and electronic microscopy. It was observed that both wettability and texture were increased with plasma treatment

Influência das tensões tectônicas na permeabilidade da formação Açu - Bacia Potiguar

The behavior of the fluid flux in oil fields is influenced by different factors and it has a big impact on the recovery of hydrocarbons. There is a need of evaluating and adapting the actual technology to the worldwide reservoirs reality, not only on the exploration (reservoir discovers) but also on the development of those that were already discovered, however not yet produced. The in situ combustion (ISC) is a suitable technique for these recovery of hydrocarbons, although it remains complex to be implemented. The main objective of this research was to study the application of the ISC as an advanced oil recovery technique through a parametric analysis of the process using vertical wells within a semi synthetic reservoir that had the characteristics from the brazilian northwest, in order to determine which of those parameters could influence the process, verifying the technical and economical viability of the method on the oil industry. For that analysis, a commercial reservoir simulation program for thermal processes was used, called steam thermal and advanced processes reservoir simulator (STARS) from the computer modeling group (CMG). This study aims, through the numerical analysis, find results that help improve mainly the interpretation and comprehension of the main problems related to the ISC method, which are not yet dominated. From the results obtained, it was proved that the mediation promoted by the thermal process ISC over the oil recovery is very important, with rates and cumulated production positively influenced by the method application. It was seen that the application of the method improves the oil mobility as a function of the heating when the combustion front forms inside the reservoir. Among all the analyzed parameters, the activation energy presented the bigger influence, it means, the lower the activation energy the bigger the fraction of recovered oil, as a function of the chemical reactions speed rise. It was also verified that the higher the enthalpy of the reaction, the bigger the fraction of recovered oil, due to a bigger amount of released energy inside the system, helping the ISC. The reservoir parameters: porosity and permeability showed to have lower influence on the ISC. Among the operational parameters that were analyzed, the injection rate was the one that showed a stronger influence on the ISC method, because, the higher the value of the injection rate, the higher was the result obtained, mainly due to maintaining the combustion front. In connection with the oxygen concentration, an increase of the percentage of this parameter translates into a higher fraction of recovered oil, because the quantity of fuel, helping the advance and the maintenance of the combustion front for a longer period of time. About the economic analysis, the ISC method showed to be economically feasible when evaluated through the net present value (NPV), considering the injection rates: the higher the injection rate, the higher the financial incomes of the final project

Estudo dos parâmetros operacionais do processo de combustão in situ em reservatório de petróleo pesado

The occurrence of heavy oil reservoirs have increased substantially and, due to the high viscosity characteristic of this type of oil, conventional recovery methods can not be applied. Thermal methods have been studied for the recovery of this type of oil, with a main objective to reduce its viscosity, by increasing the reservoir temperature, favoring the mobility of the oil and allowing an increasing in the productivity rate of the fields. In situ combustion (ISC) is a thermal recovery method in which heat is produced inside the reservoir by the combustion of part of the oil with injected oxygen, contrasting with the injection of fluid that is heated in the surface for subsequent injection, which leads to loss heat during the trajectory to the reservoir. The ISC is a favorable method for recovery of heavy oil, but it is still difficult to be field implemented. This work had as an objective the parametric analysis of ISC process applied to a semi-synthetic reservoir with characteristics of the Brazilian Northeast reservoirs using vertical production and vertical injection wells, as the air flow injection and the wells completions. For the analysis, was used a commercial program for simulation of oil reservoirs using thermal processes, called Steam, Thermal and Advanced Processes Reservoir Simulator (STARS) from Computer Modelling Group (CMG). From the results it was possible to analyze the efficiency of the ISC process in heavy oil reservoirs by increasing the reservoir temperature, providing a large decrease in oil viscosity, increasing its mobility inside the reservoir, as well as the improvement in the quality of this oil and therefore increasing significantly its recovered fraction. Among the analyzed parameters, the flow rate of air injection was the one which had greater influence in ISC, obtaining higher recovery factor the higher is the flow rate of injection, due to the greater amount of oxygen while ensuring the maintenance of the combustion front

Modelos matemáticos para estimativa do consumo máximo de oxigênio pela ventilometria de esforço em indivíduos saudáveis

The relation between metabolic demand and maximal oxygen consumption during exercise have been investigated in different areas of knowledge. In the health field, the determination of maximal oxygen consumption (VO2max) is considered a method to classify the level of physical fitness or the risk of cardiocirculatory diseases. The accuracy to obtain data provides a better evaluation of functional responses and allows a reduction in the error margin at the moment of risk classification, as well as, at the moment of determination of aerobic exercise work load. In Brasil, the use of respirometry associated to ergometric test became an opition in the cardiorespiratory evaluation. This equipment allows predictions concerning the oxyredutase process, making it possible to identify physiological responses to physical effort as the respiratory threshold. This thesis focused in the development of mathematical models developed by multiple regression validated by the stepwise method, aiming to predict the VO2max based on respiratory responses to physical effort. The sample was composed of a ramdom sample of 181 healthy individuals, men and women, that were randomized to two groups: regression group and cross validation group (GV). The voluntiars were submitted to a incremental treadmill test; objetiving to determinate of the second respiratory threshold (LVII) and the Peak VO2max. Using the método forward addition method 11 models of VO2max prediction in trendmill were developded. No significative differences were found between the VO2max meansured and the predicted by models when they were compared using ANOVA One-Way and the Post Hoc test of Turkey. We concluded that the developed mathematical models allow a prediction of the VO2max of healthy young individuals based on the LVII

Efeitos da sintomatologia depressiva na mobilidade de idosos de um centro urbano do nordeste brasileiro

O processo de envelhecimento da humanidade é um fenômeno mundial e nas últimas décadas a população brasileira tem acompanhado essa tendência. No entanto, este fenômeno somente pode ser considerado como uma real conquista em termos sócios demográficos na medida em que se agregue qualidade aos anos adicionais de vida para a população. Em populações idosas, a incapacidade funcional e os sintomas depressivos tornaram-se importantes conceitos tanto por suas consequências para a saúde pública, quanto pelo impacto na qualidade de vida dessas populações. Este estudo tem como objetivo verificar se há associação entre os sintomas depressivos e o desempenho funcional de idosos comunitários. Foram avaliados 313 idosos de um centro urbano do nordeste brasileiro através das baterias de testes; Center for Epidemiologic Studies Depression CES-D e Short Physical Performance Battery - SPPB; além de variáveis relacionadas ao estado físico, condições crônicas, função cognitiva e características sócio demográficas. Foram utilizadas medidas de correlação e aplicado método de análise multivariada para construir um modelo explicativo da influência da sintomatologia depressiva no desempenho funcional. Os resultados revelaram que as mulheres apresentaram mais sintomas depressivos (p< 0.01) e pior desempenho funcional (p< 0.01) que os homens. Os indivíduos com sintomatologia depressiva apresentaram pior desempenho funcional, especialmente as mulheres. A idade, o sexo feminino, o estado de saúde percebido, o nível de função cognitiva e o Índice de massa corporal foram identificados como fatores associados ao desempenho funcional na amostra estudada. Os resultados deste estudo permitem inferir a relação de associação entre sintomas depressivos e desempenho funcional em uma população de idosos de um centro urbano no nordeste do Brasil. Estes resultados fornecem informações úteis para intervenções terapêuticas adequadas voltadas para a prevenção do declínio na mobilidade em idosos

Mobilidade do sulfentrazone em Nitossolo Vermelho e em Neossolo Quartzarênico

O objetivo deste trabalho foi determinar a mobilidade do herbicida sulfentrazone em duas classes de solos (Nitossolo Vermelho e Neossolo Quartzarênico), em função de índices pluviométricos crescentes, sendo, portanto, influenciado pelas propriedades químicas e físicas dos solos com diferentes teores de ferro. em tubos de PVC de 10 cm de diâmetro por 50 cm de comprimento, preenchidos com os solos e saturados com água a 65% (p/p), foi aplicado o sulfentrazone (800 g ha-1). Na seqüência, foram simuladas chuvas diárias de 10 mm até atingir os índices pluviométricos de 30, 60 e 90 mm. Os tubos de PVC foram então desmontados - semeando-se Sorghum bicolor nas profundidades correspondentes de 2,5; 7,5; 12,5; 17,5; 22,5; e 30,0 cm da superfície do tubo - e mantidos em casa de vegetação por 15 dias, para avaliação da germinação e do crescimento inicial das plântulas. No final do experimento foram avaliadas as alterações morfofisiológicas que caracterizavam os efeitos tóxicos do produto, além de se medir o comprimento da parte aérea até a última lígula visível e a fitomassa seca das plantas. Quando sob precipitação de 90 mm no Neossolo Quartzarênico, o sulfentrazone formou uma banda de arraste de até 12,5 cm e, no Nitossolo Vermelho, até os 7,5 cm.

Mobilidade do sulfentrazone em latossolo vermelho e em chernossolo

Este trabalho objetivou determinar a mobilidade do sulfentrazone em duas classes de solos em função de índices pluviométricos, bem como possíveis influências das propriedades químicas e físicas de Latossolo Vermelho e Chernossolo com diferentes teores de ferro na ação do herbicida. Foram utilizados como recipientes 36 tubos de PVC de 10 cm de diâmetro por 50 cm de comprimento. Os recipientes foram preenchidos com os solos e umedecidos a 65% (p/p) da capacidade de saturação, quando se fez a aplicação do sulfentrazone (800 g ha-1 de i.a.) na área exposta dos solos. Na seqüência, foram simuladas chuvas diárias de 10 mm até atingir o índice pluviométrico desejado (30, 60 e 90 mm), sendo, posteriormente, desmontados seis tubos de cada solo (com e sem aplicação). Foram semeadas cinco sementes de sorgo (Sorghum bicolor) nas profundidades de 2,5; 7,5; 12,5; 17,5; 22,5; e 30,0 cm, mantidas em casa de vegetação por 15 dias para avaliação da germinação e do crescimento inicial. Decorrido esse tempo, foi realizada avaliação de possíveis alterações morfofisiológicas que pudessem ser caracterizadas como efeitos tóxicos do produto e mediu-se o comprimento da parte aérea até a última lígula visível. As partes aéreas foram secas em estufa com circulação forçada de ar (70 ºC por 96 horas), para obtenção de matéria seca. No Chernossolo ocorreu uniformidade da distribuição do produto ao longo do tubo, proporcional à precipitação, e no Latossolo Vermelho o sulfentrazone foi pouco móvel, permanecendo na camada superficial, independentemente da precipitação.

Efeitos de diferentes frações inspiradas de oxigênio no índice biespectral em cães submetidos à infusão contínua de propofol

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)