Prevalência de sintomas do climatério em mulheres dos meios rural e urbano no Rio Grande do Norte, Brasil

OBJETIVO: avaliar a sintomatologia climatérica e fatores relacionados entre mulheres dos meios urbano e rural do Rio Grande do Norte. MÉTODOS: estudo transversal, descritivo, envolvendo casuística de 261 mulheres climatéricas residentes em Natal e Mossoró (grupo urbano; n=130) e Uruaçu, em São Gonçalo do Amarante (grupo rural; n=131). A sintomatologia climatérica foi avaliada pelo Índice Menopausal de Blatt-Kupperman (IMBK) e Escala Climatérica de Greene (ECG). A análise estatística constou de comparações das medianas dos escores entre os grupos e regressão logística. Defi niram-se como “muito sintomáticas” as pacientes com escores ≥20, para ambos instrumentos (variável dependente). As variáveis independentes foram: idade, procedência, alfabetização, obesidade e prática de atividade física. RESULTADOS: o grupo urbano apresentou escores signifi cativamente superiores ao grupo rural, tanto para o IMBK (medianas de 26,0 e 17,0, respectivamente; p<0,0001), quanto para a ECG (medianas de 27,0 e 16,0, respectivamente; p<0,0001). Na amostra total, evidenciou-se que 56,3% (n=147) das mulheres foram classifi cadas como “muito sintomáticas”. Na comparação intergrupos, essa prevalência foi signifi cativamente mais elevada nas mulheres urbanas em relação às rurais (79,2 e 33,6%, respectivamente; p<0,05). Pela análise de regressão logística, evidenciou-se que a chance de pertencer ao grupo defi nido como “muito sintomáticas” foi maior para mulheres do meio urbano [odds ratio ajustado (OR)=7,1; 95% intervalo de confi ança a 95% (IC95%)=3,69-13,66] e alfabetizadas (OR=2,19; IC95%=1,16-4,13). A idade superior a 60 anos associou-se com menor chance de ocorrência de sintomas signifi cativos (OR=0,38; IC95%=0,17-0,87). CONCLUSÕES: a prevalência de sintomas climatéricos signifi cativos é menor em mulheres do meio rural, demonstrando que fatores socioculturais e ambientais estão fortemente relacionados ao surgimento dos sintomas climatéricos em nossa população.___________________________________ABSTRACT PURPOSE: to evaluate climacteric symptoms and related factors in women living in rural and urban areas of Rio Grande do Norte, Brazil. METHODS: a cross-sectional study involving 261 women in the climacteric was performed. A total of 130 women from Natal and Mossoró (urban group) and 131 from Uruaçu, in São Gonçalo do Amarante (rural group), were studied. Climacteric symptoms were assessed by the Blatt-Kupperman Menopausal Index (BKMI) and Greene Climacteric Scale (GCE). Statistical analysis involved comparison of median between groups and logistic regression analysis. Patients were defi ned as “very symptomatic” when the climacteric score was ≥20 for both questionnaires (dependent variable). Independent variables were: age, living area, schooling, obesity and physical activity. RESULTS: the urban group had signifi cantly higher scores than those of the rural group, both for BKMI (median of 26.0 and 17.0, respectively; p<0.0001) and for GCE (median of 27.0 and 16.0, respectively; p<0.0001). For the entire sample, a total of 56.3% (n=147) of the women were classifi ed as “very symptomatic”. This prevalence was signifi cantly higher in urban than in rural women (79.2 and 33.6%, respectively; p<0.05). Logistic regression analysis showed that the likelihood of belonging to the group defi ned as “very symptomatic” was greater for urban women [adjusted odds ratio (OR)=7.1; confi dence interval at 95% (95%CI)=3.69-13.66] who were literate (OR=2.19; 95%CI=1.16- 4.13). Individuals over the age of 60 years had less chance of having signifi cant symptoms (OR=0.38; 95%CI=0.17-0.87). CONCLUSIONS: the prevalence of signifi cant climacteric symptoms is less in women from a rural environment, showing that sociocultural and environmental factors are strongly related to the appearance of climacteric symptoms in our population

Avaliação do efeito de particulados sólidos na eficiência de um inibidor de corrosão recomendado para meios salinos com CO2

The main problem on the exploration activity on petroleum industry is the formation water resulted on the fields producing. The aggravating of this problem is correlated with the advancing technologies used on the petroleum extractions and on its secondary approach objecting the reobtainment of this oil. Among the main contaminants of the water formation are corrosives gases such as: O2, CO2 and H2S, some solids in suspension and dissolved salts. Concerning to those gases the CO2 is the one that produce significant damage for carbon steel on corrosion process of the petroleum and gas industries. Corrosion inhibitors for carbon steel in formation water is one of the most used agents in control of those damages. In this context, the poor investigations of carbon steel corrosion proceeding from solids in suspension is an opened field for studies. On this work the inhibitor effect of the commercial CORRTREAT 703 was evaluated on some specific solids in suspension at saline medium containing 10.000 ppm of de-aerated chloride using CO2 until non oxygen atmosphere been present. For that, quartz, calcium carbonate, magnetite and iron sulphide were subjected to this investigation as the selected solids. The effect of this inhibitor on corrosion process correlated with those specific solids, was measured using electrochemical (resistance of linear polarization and galvanic pair) and gravimetrical techniques. During all the experimental work important parameters were monitored such as: pH, dissolved oxygen, temperature, instantaneous corrosion rate and galvanic current. According to the obtained results it was proved that the suspension solids calcium carbonate and iron sulphide decrease the corrosion process in higher pH medium. Meanwhile the quartz and magnetite been hardness increase corrosion by broking of the passive layer for erosion. In the other hand, the tested inhibitor in concentration of 50 ppm, showed to be effective (91%) in this corrosion process

Modelagem analítica e experimental da filtração em meios porosos

Deep bed filtration occurs in several industrial and environmental processes like water filtration and soil contamination. In petroleum industry, deep bed filtration occurs near to injection wells during water injection, causing injectivity reduction. It also takes place during well drilling, sand production control, produced water disposal in aquifers, etc. The particle capture in porous media can be caused by different physical mechanisms (size exclusion, electrical forces, bridging, gravity, etc). A statistical model for filtration in porous media is proposed and analytical solutions for suspended and retained particles are derived. The model, which incorporates particle retention probability, is compared with the classical deep bed filtration model allowing a physical interpretation of the filtration coefficients. Comparison of the obtained analytical solutions for the proposed model with the classical model solutions allows concluding that the larger the particle capture probability, the larger the discrepancy between the proposed and the classical models

Simulação de fluxo de fluidos em meios porosos desordenados uma análise de efeito de escala na estimativa da permeabilidade e do coeficiente de arrasto

The present study provides a methodology that gives a predictive character the computer simulations based on detailed models of the geometry of a porous medium. We using the software FLUENT to investigate the flow of a viscous Newtonian fluid through a random fractal medium which simplifies a two-dimensional disordered porous medium representing a petroleum reservoir. This fractal model is formed by obstacles of various sizes, whose size distribution function follows a power law where exponent is defined as the fractal dimension of fractionation Dff of the model characterizing the process of fragmentation these obstacles. They are randomly disposed in a rectangular channel. The modeling process incorporates modern concepts, scaling laws, to analyze the influence of heterogeneity found in the fields of the porosity and of the permeability in such a way as to characterize the medium in terms of their fractal properties. This procedure allows numerically analyze the measurements of permeability k and the drag coefficient Cd proposed relationships, like power law, for these properties on various modeling schemes. The purpose of this research is to study the variability provided by these heterogeneities where the velocity field and other details of viscous fluid dynamics are obtained by solving numerically the continuity and Navier-Stokes equations at pore level and observe how the fractal dimension of fractionation of the model can affect their hydrodynamic properties. This study were considered two classes of models, models with constant porosity, MPC, and models with varying porosity, MPV. The results have allowed us to find numerical relationship between the permeability, drag coefficient and the fractal dimension of fractionation of the medium. Based on these numerical results we have proposed scaling relations and algebraic expressions involving the relevant parameters of the phenomenon. In this study analytical equations were determined for Dff depending on the geometrical parameters of the models. We also found a relation between the permeability and the drag coefficient which is inversely proportional to one another. As for the difference in behavior it is most striking in the classes of models MPV. That is, the fact that the porosity vary in these models is an additional factor that plays a significant role in flow analysis. Finally, the results proved satisfactory and consistent, which demonstrates the effectiveness of the referred methodology for all applications analyzed in this study.

Meios de resgatar a saúde bucal e autoestima de idosos

O presente estudo objetivou analisar as características epidemiológicas das condições de saúde bucal de 98 idosos de uma Instituição de Longa Permanência para Idosos (ILPI) e de 125 participantes de Grupos de Convivência, de bairros periféricos, socialmente semelhantes, de Fortaleza, Ceará, Brasil, para orientação do tratamento odontológico. Investigou-se a autopercepção em saúde bucal desses idosos a fim de realizar uma avaliação comparativa entre eles e com os levantamentos epidemiológicos de base nacional (SB Brasil) e de base estadual (SB Ceará). Devido a alguns idosos da ILPI recusarem o tratamento dentário e a identificação do elevado percentual de demenciados, optou-se por realizar uma avaliação cognitiva, o Mini Exame do Estado Mental (MEEM) visando identificar os aptos à reabilitação oral. Métodos: abordagem epidemiológica do tipo transversal, sendo a coleta de dados realizada por cinco examinadores, utilizando os critérios recomendados pela OMS (1997). Resultados: O CPO-D médio encontrado na ILPI, foi de 29,88, com predomínio do componente perdido (93,27%) enquanto o CPO-D médio dos não institucionalizados fixou-se em 30,17, com predomínio do componente perdido (63,70%). Também se avaliou o uso e a necessidade de prótese dentária: dos residentes na ILPI, 10,20% usavam prótese superior e 3,06%, inferior; 94,90% necessitavam de prótese superior e 97,96% de inferior; sendo a prótese total foi o tipo mais prevalente, 88,78% para ambos os arcos. O percentual do uso de prótese dos não institucionalizados foi 71,20% no arco superior, sendo 66,40% prótese total; já para o arco inferior, 32,80%, das quais 31,20% era prótese total. No presente estudo, tanto para uso quanto para necessidade, considerando ambos os arcos, a diferença entre os idosos institucionalizados e não institucionalizados foi estatisticamente significativa pelo teste Qui - quadrado (p<0,001). Como resultado do MEEM, observou-se deterioração cognitiva (escore ≤ 12) em 37,25% dos entrevistados, bem como um declínio cognitivo com o avanço da idade. Conclusões: Os resultados apontam que há um maior percentual de uso de prótese total no arco superior e maior frequência quanto à ausência de próteses de qualquer tipo no arco inferior. Evidenciou-se que os idosos pesquisados foram submetidos a tratamento mutilador e, como consequência necessitam de reabilitação oral, o que pressupõe a necessidade de políticas públicas para que isso ocorra efetivamente. Os participantes deste estudo caracterizam-se por uma autopercepção positiva da sua saúde bucal, a despeito das condições clínicas insatisfatórias e de precária saúde bucal, com acentuada prevalência de cárie dentária e edentulismo. O MEEM revelou deficiência cognitiva na maioria dos idosos, confirmando que a sua aplicação, previamente à reabilitação oral pode evitar desperdícios financeiros.Tais achados refletem a necessidade de implantação de políticas reabilitadoras em saúde bucal voltadas para o idoso; baseadas na perspectiva da integralidade como princípio doutrinário do Sistema Único de Saúde, o que redundaria numa melhor qualidade de vida, tanto pela melhor mastigação, digestão e nutrição, pelo maior aproveitamento dos alimentos, quanto pelo favorecimento à comunicação, pela dicção e fala, contribuindo para a socialização e consequente elevação da autoestima dessa clientela.

Responsabilidade social empresarial: modalidades e grau de participação em meios de hospedagem em Ponta Negra, Natal/RN

That work has as objective to investigate and to analyze the strategies which they were developed by companies of lodging means with ends of social responsibility in Rio Grande do Norte (RN). Therefore, it got data along with the Office of Tourism of the Municipal district of Natal , the Office of Tourism of RN and the cadasters of the firms of the lodging means in the district of Ponta Negra. In after research of field, it verified the enterprises that now develop lodging activities in that quarter in Ponta Negra. It applied Instrument of research which it was elaborated based on the set of indicators of social responsibility of Ethos Institute, structured with binary questions and some open ones. It shows as results which actions the investigated companies develop. Confronting these results with researched theoretical referencial, it points an intermediate degree of socially responsible actions. Comparing with the evaluation accomplished by Ethos Institute, the investigated firms are in incipient condition, with punctual actions, however, they already present the awakening about this thematic

Mecanismos de segurança para um sistema cooperativo de armazenamento de arquivos baseado em P2P

Previous works have studied the characteristics and peculiarities of P2P networks, especially security information aspects. Most works, in some way, deal with the sharing of resources and, in particular, the storage of files. This work complements previous studies and adds new definitions relating to this kind of systems. A system for safe storage of files (SAS-P2P) was specified and built, based on P2P technology, using the JXTA platform. This system uses standard X.509 and PKCS # 12 digital certificates, issued and managed by a public key infrastructure, which was also specified and developed based on P2P technology (PKIX-P2P). The information is stored in a special file with XML format which is especially prepared, facilitating handling and interoperability among applications. The intention of developing the SAS-P2P system was to offer a complementary service for Giga Natal network users, through which the participants in this network can collaboratively build a shared storage area, with important security features such as availability, confidentiality, authenticity and fault tolerance. Besides the specification, development of prototypes and testing of the SAS-P2P system, tests of the PKIX-P2P Manager module were also performed, in order to determine its fault tolerance and the effective calculation of the reputation of the certifying authorities participating in the system

Simulação de reservatórios não convencionais para armazenamento de gás natural veicular

The investigation of viability to use containers for Natural Gas Vehicle (NGV) storage, with different geometries of commercial standards, come from necessity to join the ambient, financial and technological benefits offered by the gas combustion, to the convenience of not modify the original proposal of the automobile. The use of these current cylindrical models for storage in the converted vehicles is justified by the excellent behavior that this geometry presents about the imposed tensions for the high pressure that the related reservoirs are submitted. However, recent research directed toward application of adsorbent materials in the natural gas reservoirs had proven a substantial redusction of pressure and, consequently, a relief of the tensions in the reservoirs. However, this study considers alternative geometries for NGV reservoirs, searching the minimization of dimensions and weight, remaining capacity to resist the tensions imposed by the new pressure situation. The proposed reservoirs parameters are calculated through a mathematical study of the internal pressure according to Brazilian standards (NBR) for pressure vessels. Finally simulations of the new geometries behavior are carried through using a commercially avaible Finite Element Method (FEM) software package ALGOR® to verify of the reservoirs efficincy under the gas pressure load

Desenvolvimento de sistemas micro e nanoestruturados de quitosana/MDI para aplicações cosméticas

Currently, studies in the area of polymeric microcapsules and nanocapsules and controlled release are considerably advanced. This work aims the study and development of microcapsules and nanocapsules from Chitosan/MDI, using a new technique of interfacial polycondensation combined to spontaneous emulsification, for encapsulation of BZ-3. It was firstly elaborated an experimental design of 23 of the particle in white without the presence of BZ-3 and Miglyol, where the variables were the concentrations of MDI, chitosan and solvent. Starting from the data supplied by the experimental design was chosen the experiment with smaller particle diameter and only added like this BZ-3 and Miglyol. The suspension containing concentrations of 6.25 mg/mL, 12.5 mg/mL, 18.75 mg/mL, 25 mg/mL of BZ-3 were prepared, nevertheless, during the storage time, these formulations presented drug precipitates in the suspensions of 18.75 mg/mL and 25 mg/mL of BZ-3. This apparition of precipitate was attributed to the diffusion of BZ-3 for the aqueous phase without any encapsulation, suggesting so the use of the smaller concentrations of the BZ-3. The suspension containing 6.25mg/mL of BZ3 presented average size of 1.47μm, zeta potential of 61 mV, pH 5.64 and this sample showed an amount of BZ-3 and drug entrapment of 100 %. The suspension containing 12.5mg/mL of BZ-3 presented average size of 1.76μm, zeta potential of 47.4 mV, pH 5.71 and this sample showed an amount of BZ-3 and drug entrapment of 100 %. Then, showing such important characteristics, these two formulations were chosen for futher continuity to the study. These formulations were also characterized by the morphology, FTIR, stability for Turbiscan, DSC and a study of controlled release of the BZ-3 was elaborated in different receiving means

Relações entre mídia e lazer:o capitalismo, os meios e a apropriação do tempo livre nas sociedades industrial e pós-industrial

This research aims to understand the relationship between media, capitalism and ownership of free time for leisure practices in industrial societies and postindustrial. Searching is thus a conceptual framework that takes into account the kind of ideology that naturalizes the relationship of leisure with the foundations of contemporary media, and the media only with leisure, forgetting their insertion in the labor and industrial relations in society. We intend to demonstrate that every mode of production, in the capitalist system, entails a mode of reproduction. Methodologically, this is a first approximation, from theoretical concerns already performed, constituting a theoretical research, bibliographic and descriptive character. The results of the text drives us to the conclusion that the work and leisure spheres tend to be less and less differentiated, since both remain as activities of product management with the same intellective protocols, based on information and communication technology, and that accordingly, the media favors an expansion of productive activity even during leisure time

Inibição à corrosão do aço AISI 1020, em meios ácido e salino, por tensoativos e substâncias nitrogenadas microemulsionados

Corrosion inhibition efficiency of saponified coconut oil (SCO) and sodium dodecilbenzene sulfonate (DBS) surfactants in AISI 1020 carbon steel was evaluated by electrochemical methods. These surfactants were also evaluated as microemulsion systems (SCO-ME and DBS-ME), of O/W type (water-rich microemulsion), in a Winsor IV region. They were obtained according to the following composition: 15% SCO, 15% butanol (30% Co-surfactant/Surfactant C/T), 10% organic phase (FO, kerosene) and 60% aqueous phase (FA). These systems were also used to solubilize the following nitrogenated substances: Diphenylcarbazide (DC), 2,4-dinitro-phenyl-thiosemicarbazide (TSC) and the mesoionic type compound 1,3,4-triazolium-2-thiolate (MI), that were investigated with the purpose of evaluating their anticorrosive effects. Comparative studies of carbon steel corrosion inhibition efficiencies of free DBS and DBS-ME, in brine and acidic media (0.5%), showed that DBS presents better inhibition results in acidic media (free DBS, 89% and DBS-ME, 93%). However, the values obtained for DBS in salted solution (72% free DBS and 77% DBS-ME) were similar to the ones observed for the SCO surfactant in brine (63% free SCO and 74% SCO-ME). Analysis of corrosion inhibition of the nitrogenated substances that were solubilized in the SCO-ME microemulsion system by the linear polarization method in brine (0.5% NaCl) showed that such compounds are very efficient an corrosion inhibitors [DC-ME-SCO (92%), TSC-ME-SCO (93%) and MI-ME-SCO (94%)]

GESTÃO AMBIENTAL E COMPETITIVIDADE EM DESTINOS TURÍSTICOS: percepção dos gestores de pequenos meios de hospedagem de Natal/RN sobre o uso de práticas ambientais como fator de competitividade

The present work aimed at investigating the small hotel managers perceptions from Natal/RN concerning the environmental practice uses as a competitive factor. This study is characterized as a descriptive exploratory research that used an aleatory probabilistic sample followed by the application of collect data instrument (questionnaire). The small hotels located in Natal/RN were the study participants and the specific location where 35 questionnaires were answered. Based on the data and on the mangers point of view, it is possible to comprehend that, among the presented indicators, the development of environmental programs in the hotel enterprise is showed as the least important for the client s choice. As the main conclusion it is relevant to argue that, according to the small hotel managers, the guests do not still search for hotels that implement environmental practices. On the other side, the interviewed managers believe that the use of these practices can generate a great competitive advantage in relation to their competitors. The information obtained by this present research will be able to contribute to establish a contemporary panorama in relation to the importance attributed by the managers concerning the use of environmental practices in small hotel enterprises in Natal/RN. In addition the correct use of this information can generate possibilities of major competitiveness in this segment

Por uma pedagogia do oprimido midiático: meios de comunicação e suas intervenções na escola

En este trabajo nos ocupamos de la convergencia de la fotografía, el vídeo y la música, intermediado por una estación de radio en la escuela, instalada en la escuela Municipal de Djalma Maranhão, Natal, Rio Grande do Norte, en una clase de 5º año de jóvenes y adultos en el año escolar 2007. Se analizan las intervenciones causados los que participan en la vida escolar, a partir de las actividades realizadas por ellos, en la producción de programas de radio. Los procedimientos metodológicos sobre la base de la etnometodologia (COULON, 1995a, 1995b), en la investigación cualitativa (BOGDAN, BIKLEN, 1999, DENZIN y LINCOLN, 2006), participante como observador (MAY, 2004) y la investigación-acción (THIOLLENT, 1992). La comprensión de Paulo Freire en la comunicación e la educación es nuestro principal referente teórico. Los experimentos citados en los medios de comunicación revelaron varias posibilidades de mejora en la enseñanza y el aprendizaje, como el aumento de la autoestima de los estudiantes, social y de inclusión educativa de personas con discapacidad, disminución de la timidez y facilitar la comunicación entre los sujetos, lo que permite el diálogo entre ellos, intervino en sus relaciones sociales, más allá de los límites de la escuela. La investigación confirma, entonces, que la comunicación y la educación son parte de la misma naturaleza

Caracterização geológico-geofísica do meio aqüífero fissural : uma contribuição aos modelos de fluxo e armazenamento de água subterrânea

Northeastern Brazil is mainly formed by crystalline terrains (around 60% in area). Moreover, this region presents a semi-arid climate so that it is periodically subject to drought seasons. Furthermore, ground water quality extracted fromwells usually presents poor quality because of their high salinity contents. Nevertheless, ground water is still a very important source of water for human and animal consumption in this region. Well sitting in hard rocks terrains in Northeastern Brazil offers a mean success index of aboul 60%, given that a successful siting is defined by a well producing at least 0.5 m³/h. This low index reveals lack of knowledga about the true conditions of storage and percolation of ground water in crystalline rocks. Two models for structures storing and producing ground water in crystalline rocks in Northeastem Brazil have been proposed in the literature. The first model,tradnionally used for well sitting since the sixties are controlled by faults or fractures zones. This model is commonly referred, in Brazilian hydrogeological literature, as the "creek-crack" model (riacho-fenda in Portuguese). Sites appearing to present dense drainage network are preferred for water well siting - particularly at points where the drainages cross-cul each other. Field follow up work is usually based only on geological criteria. The second model is the "eluvio-alluvial through" (calha eluvio-aluvionar in Portuguese); it is also described in the literature but it is not yet incorporated in well sitting practice. This model is based on the hypothesis that reclilinear drainages can also be controlled by the folietion of the rock. Eventually, depending upon the degree of weathering, a through-shaped structure filled with sediments (alluvium and regolith) can be developed which can store and water can be produced from. Using severalfield case studies, this Thesis presents a thorough analysis ofthe two above cited models and proposes a new model. The analysis is based on an integrated methodological approach using geophysics and structural geology. Both land (Resitiviy and Ground Penetrating Radar- GPR) and aerogeophysical (magnetics and frequency domain eletromagnetics) surveys were used. Slructural analysis emphasized neolectonic aspects; in general, itwas found that fractures in the E-W direction are relatively open, as compared to fracturas inthe N-S direction, probably because E-W fractures were opened by the neotectonic stress regime in Northeastern Brazil, which is controlled by E-W compression and N-S extension. The riacho-fenda model is valid where drainages are controlled by fractures. The degree of fracturing and associated weathering dictale the hydrogeological potential of the structure. Field work in structural analogues reveals that subvertical fractures show consistent directions both in outcrop and aerophotograph scales. Geophysical surveys reveal subvertical conductive anomalies associated to the fracture network controlling the drainage; one of the borders of the conductive anomaly usually coincide wih the drainage. An aspect of particular importance to the validation of fracture control are the possible presence of relalively deep conductive anomalies wihoul continuation or propagalion to the surface. The conductive nature of lhe anomaly is due to the presence of wealhered rock and sedirnenls (alluvium and/or regolilh) storing ground waler which occur associated to the fracture network. Magnetic surveys are not very sensisnive to these structures.lf soil or covering sedirnents are resislive (> 100 Ohm.m), GPR can ba used to image precisely lhe fracture network. A major limialion of riacho-fenda model, revealed by GPR images, is associated to the fact thal subhorizontal fractures do play a very important role in connecting the fracture network, besides connect shallow recharge zones to relalively deep subvertical frecture zones. Iffractures play just a secondary control on the drainage, however, r/acho-fenda model may have a very limiled validny; in these cases, large portions oflhe drainage do nol coincide wilh frectures and mosl oflhewells localed in lhe drainage surrounding would resull dry. Usually, a secondary conlrol on lhe drainage by Ihefraclure networkcan be revealed only wilh detailed geophysical survey. The calha elClv1o-aluvlonarmodel is valid where drainages are conlrolled by folialion. The degree 01 wealhering 01 lhe lolialion planes dictales lhe hydrogeological polenlial 01 lhe slruclure. Outcrop analysis reveals Ihal lolialion and drainage direclions are parallel and Ihal no Iraclures, orfraclures wilh diflerent directions 01 lhe drainage direclion occur. Geophysical surveys reveal conduclive anomalies in a slab lorm associaled 10 lhe Ihrough 01 lhe wealhered rock and sedimenls (alluvium and/or regolith). Magnelic surveys can ofler a very good conlrol on lolialion direclion. An importanl aspect 10 validale lolialion conlrol are lhe presence 01 conductive anomalies showing shallow and deep portions area which are linked. Illhere is an exlensive soil cover, r/acho-fenda and calha eIClv1o-aluv/onar conlrols can be easily misinlerpreled in lhe absence 01 geophysical conlrol. Certainly, Ihis lacl could explain at leasl a part of lhe failure index in well sitting. The model wealhering sack (bolsllo de Intempertsmo in Portuguese) is proposed to explain cases where a very inlensive wealhering occur over lhe crystalline rock so Ihal a secondary inlerslilial porosity is crealed. The waler is Ihen stored in lhe porous of lhe regolilh in a similar mannerlo sedimentary rocks. A possible example ofthis model was delecled by using land geophysical survey where a relalivelyvery deep isolaled conduclive anomaly, in a slab form, was delected. Iflhis structure does store ground waler, certainly Ihere must be a link 01 lhe deep slructure wilh lhe surface in orderlo provide walerfeeding. This model mighl explain anomalous waler yields as greal as 50 m³/h Ihalsomelimescan occur in crystalline rocks in Northeaslern Brazil

Modelagem Matemática e Computacional de fenômenos eletrocinéticos em meios porosos carregados eletricamente

In this work we present a mathematical and computational modeling of electrokinetic phenomena in electrically charged porous medium. We consider the porous medium composed of three different scales (nanoscopic, microscopic and macroscopic). On the microscopic scale the domain is composed by a porous matrix and a solid phase. The pores are filled with an aqueous phase consisting of ionic solutes fully diluted, and the solid matrix consists of electrically charged particles. Initially we present the mathematical model that governs the electrical double layer in order to quantify the electric potential, electric charge density, ion adsorption and chemical adsorption in nanoscopic scale. Then, we derive the microscopic model, where the adsorption of ions due to the electric double layer and the reactions of protonation/ deprotanaç~ao and zeta potential obtained in modeling nanoscopic arise in microscopic scale through interface conditions in the problem of Stokes and Nerst-Planck equations respectively governing the movement of the aqueous solution and transport of ions. We developed the process of upscaling the problem nano/microscopic using the homogenization technique of periodic structures by deducing the macroscopic model with their respectives cell problems for effective parameters of the macroscopic equations. Considering a clayey porous medium consisting of kaolinite clay plates distributed parallel, we rewrite the macroscopic model in a one-dimensional version. Finally, using a sequential algorithm, we discretize the macroscopic model via the finite element method, along with the interactive method of Picard for the nonlinear terms. Numerical simulations on transient regime with variable pH in one-dimensional case are obtained, aiming computational modeling of the electroremediation process of clay soils contaminated