44 resultados para Didactica Magna


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Dans le scénario actuel marqué par l'insuccès de l'école publique en alphabétiser les enfants, l'objectif de cet étude est d'analyser, dans le cadre d'une école publique (dont les enfants, d'après les numéros officiels, deviennent lettrés au cours des trois premières années), des actions de gestion scolaire qui favorisent le processus d'alphabétisation. Pour cela nous suivons les principes de la méthode qualitative et adoptons l‟études de cas. Le terrain empirique est une école publique de la ville de Parnamirim (RN) et les sujets sont sa directrice, la vice-directrice, trois enseignantes des trois premières années de l'enseignement fondamental, deux coordinatrices pédagogiques, deux parents et six enfants. Pour la construction des données nous adoptons le questionnaire, l'analyse documentaire, des entretiens semi-dirigés et l'observation non-participante. Les fondements théoriques qui servirent de jalon à nos interprétations se retrouvent dans les conceptions actuelles de gestion éducationnelle et d'alphabétisation, ainsi que sur le processus d'apprentissage et de développement et pratique éducative. Dans cette étude, le concept de gestion est pris comme manière de dépasser la perspective bornée, bureaucratique, comme condition fondamentale de la qualité d'enseignement et de transformation de la propre identité des écoles, des systèmes d'enseignement et de l'éducation brésilienne; un concept déposé sur (et à partir de ) la mobilisation dynamique des sujets humains organisés collectivement. L'alphabétisation d'enfants est comprise en tant qu'enseignement-apprentissage du langage écrit dans une processus qui entoure deux dimensions indissociables: l'appropriation du système d'écriture alphabétique et le développement d'habilités/pratiques textuelles, dont les spécificités de développement impliquent systématisation et internationalité, caractéristiques de l'école en tant qu'institution éducative. A travers l'analyse des données fondé en quelques principes de l'analyse de contenu nous constatâmes que la gestion de l'école objet de la recherche, bien que marquée par des contradictions, développe des actions qui exercent un rôle fondamental dans les processus et résultats de l'apprentissage de l'écriture par les enfants. Ayant identifié les actions, nous construisîmes les catégories suivantes: 1) Actions relatives à l'organisation de l'école comme institution; 2) Actions relatives à organisation du processus enseignement-apprentissage; et sous-catégories: 1.1 Création et manutention d'infra-structure adéquate; 1.2 Promotion du travail collectif et autonome des professionnels; 1.3 Construction/formation permanente de l'équipe de professeurs; 1.4 Participation des parents dans la dynamique de l'école; 2.1 Disponibilité de ressources pour l'apprentissage; 2.2 Systématisation de la planification du processus enseignement-apprentissage e 2.2.1 Systématisation de l'évaluation de l'apprentissage. La catégorisation construite, bien que sa réflexion, signale que les actions qui favorisent l'alphabétisation des enfants s'approchent des conceptions d'une éducation de qualité sociale et de la démocratisation de l'éducation, bien que la propre institution de la gestion de l'école ne soit, pas encore, démocratisée. Notre étude réaffirme que la gestion de l'école, comme tout pratique humaine et sociale, a un caractère essentiellement contradictoire, inachevé et lacunaire, mais qui, jusqu'aux limites des contradiction, l'on trouve des possibilités, mises en évidence dans les actions de la gestion intimement articulées avec le succès de l'apprentissage et qui, par conséquent, peuvent construire une référence pour la réflexion sur les pratiques de gestion de l'école engagées engagée avec l'apprentissage et avec l'alphabétisation des enfants

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This work focuses on the educational policies, on the necessity of adopting new models of administration of the education, as well as the implementation of reforms in this filed during the 1990 s. It analyzes the strategies of decentralization of the education in Rio Grande do Norte, disclosing practices conceived in the governmental plans and programs. It also aims to evidence the aspects of the decentralization proposed in the educational system management model, adopted by the Department of Education and Culture of Rio Grande do Norte from 1995 to 1999. Bibliographic researches and documental analysis were used as sources and semi-structured interviews were held in order to collect data. This work also highlights the concepts of participation, autonomy and democratic management intrinsic to the process of decentralization in the education field. It is clear that decentralization, as the vector of democracy, requires not only certain conditions that assure the universal access to the necessary information, but also that all segments of the institution have a voice in the collegiates and that the management and decision-making processes be transparent. This analysis reveals the importance of creating means to promote autonomy, participation and democratic management in order to consolidate a decentralized system. It is also clear that these mechanisms have been proposed in a vague way by the governmental guidelines, which makes it harder to consolidate a democratic management model. Having this perspective as a parameter, it is possible to realize that the adoption of a management model prompted by the law hasn t established effective means of participation that, consequently, should provide decision centralizers which opposed to the democratic actions

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The present research to explorer the configurations that come being given to the autonomy of the school, since the decade of 1990. We investigate the implementation of the principle of the autonomy in the public system of education of the State of Pernambuco and, specifically, in four school units and this schools its in the quarters of Stubborn Brasilia Teimosa and Casa Amarela, both located in Recife. We try to know if the implementation of the autonomy of the school is circumscribed in the process of productive reorganization, it was evidenced that the inclusion of this principle in the educational politics - in the scopes national and state - obeyed the dynamics of retraction that, in the neoliberal context, the performance of the State in relation to the public education and the school characterizes, with consequence impact in the investigated schools. From the empirical inquiry it was identified to the occurrence of a movement realized for the social actors of the schools research in direction to the construction of the pertaining to school autonomy; this movement presenting some limits and fragilities. It was evidenced despite this movement varied of intensity in the measure where the social actors of the schools had developed levels of dinamics processes (in greater or minor degree) related with the diverse expressions of democratic management that can occur into the school, such as: elaboration of the Politician-Pedagogical Project, institution and functioning of the Pertaining to school Advice, etc. The set of the carried through analyses made possible that it concluded that, in the context neoliberal and delimited to the investigated time and space, the implementation of the autonomy of the school comes if giving in way to a complex movement of construction

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Le présent étude analyse les effets de la politique de financement de l éducation de base, par les Fonds contables, Fundef et Fundeb, et sa proposition de valorisation de l enseignement, en considerant les dimensions de la carrière et de la rémunération des professeurs de l éducation publique de l état du Rio Grande do Norte, entre les années de 1996 et 2000. Pour comprendre les contraintes de l évaluation des politiques publiques, en cherchant aussi les contribution en Marx (1996) selon qui « le concret est concret » et que la dialétique du concret peut appuyer pour la tentative de capter le fenomène étudié. On a utilisé encore le référentiel bibliographique relatif au financement de l éducation et la valorisation de l enseignement à partir de la littérature reférente aux dimensions de l objet (Fundef et Fundeb) et (carrière et rémuneration). Dans la recherche documental, au-delà des législations, directrices nationales et locales pertinentes, se sont utilisés des donnés référents aux ressources, disponibles à la Finbra, Trésor National, SIOPE/RN, INEP/MEC, des informations du résumé de la feuille et feuille de payement du Secrétariat d État, de l Éducation et de la Culture (SEEC) et 289 bulletins de salaire de 21 professeurs. On a réalisé interview semi structurée avec une quantité de 9 professeurs, reférent à la carrière, et un questionaire appliqué à 12 professeurs relatif à la remuneration. On considère que sur les résultats reférents aux indicateurs éducationnel, dans la période Fundef il y a eu une réduction des inscriptions aux écoles de l état comme aussi aux fonctions des professeurs de l Enseignement Fondamental, et cela correspond à 37%. À partir de la vigence du Fondebe (2007 - 2010) ces indicateurs ont équalisé. Pendant toute la période, 1996 et 2010 il y a eu une augmentation des inscriptions de 119,03%, et aussi aux fonctions des professeurs de 77,44%. Par rapport aux informations de financement, on a constaté que, du minimum exigé (60%) sur l aplication des fonds à la rémuneration de l enseignant, on applique pour la période des deux fonds, plus que le minimum exigé, c est-à-dire de 83,29% à 98,89% des fonds. Les effets des fonds sur la carrière des 9 professeurs n ont pas été satisfactoires, si l on considère la promotion et la progression. Au cas de la promotion des 9 de ces professeurs, un seul a évolué son niveau (les titres) mais a, au même temps, rétroagit dans sa progression. Pour la progression des 9 professeurs, 8 d entre eux ont sa progression retardée, ce qui correspond à entre 2 et 5 classes, et ce qui provoque un préjudice qui varie entre 10% à 45% sur sa remunération. La différence d une classe à l autre correspond à 5% de son salaire. On évalue que les avantages financières contribuent pour la remunération avec un pourcentage plus élevé que son salaire, ce qui diminuent pendant lo Fundeb. Par rapport à la remunération un professeur de 24 ans de service avec formation, n arrive même pas à gagner 2 salaires minimums. Le professeur de 30 ans de service, maître, reçoit un salaire, en 2010, qui correspond a moins de 3 salaires minimums, c est-à-dire, une proportion de 2,82 et une remuneration qui correspond à un peu plus que 3 salaires minimums, c est-à-dire, une proportion de 3,66. L enseignement n est pas très favorisé si on le met face à d autres profession qui ont aussi l exigence de formation supérieure, ce qui provoque un effet négatif pour voir l enseignement comme profession. À propos des effets sur la rémuneration, on conclue qu il y a eu une amélioration mais encore insufisante, surtout si l on compare au Salaire Minimum annuel. On évalue que les fonds Fundef et Fundeb n ont pas été capables de promouvoir la valorisation de l enseignement dans le contexte de carrière et rémuneration. On observe quelques résultats négatif dans la politique de fonds, une fois qu il y aurait en avoir avec l incapacité de tel politique en promouvoir la dite valorisation de l enseignement, ce qui est une des causes, le financement avec des restriction budgétaire

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This work discusses about the teacher salary in the primary school after the creation of the Fundo de Manutenção e Desenvolvimento do Ensino Fundamental e Valorização do Magistério (Fundef), in the public schools in Natal/RN, from 1996 to 2006. The salary is considered one of the politic dimensions of the valorization of teaching. We aim to analyze the implication of this fund to the teacher remuneration, with different levels of training, in the early career, comparing it to the annual minimum salary, during the same period. This study has a historic-critic approach, establishing the relationship between the elements into a particular context (valorization of teaching/ teacher salary) and the elements from general contexts (financing/ Fundef). Analyzing data of the teacher remuneration from municipal payroll and comparing them to the annual national minimum salary gave us the result that the teachers, in their early career, do not have remuneration with a satisfactory evolution. Teachers that finished high school received until three minimum salaries before the creation of Fundef (1996-1997), after that (in 1998) they received under two minimum salary. In addition to this, independently of the level of the teacher training, their remuneration is under three minimum salaries. Hence, we can infer that the politic of funds is distant from the ideal to valorize the professional of the municipal teaching

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This study board the FUNDEF social control council implementation in Parnamirim/RN city, concerning their representatives participation in the accompaniment (decision power) in resort, in front of governmental politics of decentralization, unleashed in 90´s, seen in decentralization process needs the society participation in decisions of educative institutions and represent an efficient way of solve the problems difficult the educational management actions. For this, the council creation of Brazil manager configure, since the 80´s, detaching, and the single characterizing, in actual context. The objective is raise pertinent questions of thematic of representatives members participation of collegiate organs, evidencing the decision power of these, in public resource control. The theory-methodological referential the literature treat the participation and power decision of FUNDEF social control decision, such as politics directrix that rules this council. It utilizes as proceeding of collecting data the semi-structured interview and analyze of meeting register to understand the empirics of council implantation in this city, in view of that the electoral process configured in 2003, showed as a innovation, because the counselor is indicated by the local public power representatives (in this case the education municipal secretary). The research result show the representatives have difficult, to accompany the FUNDEF resources amount, particularly in concern in the financial resources (ratio) over plus. Finally, emphasize the importance of democratization in the relations between the state and civil society, elucidating and exciting reflections a: democratic participation in control of public recourses for education, educational management and civil society mobilization in access of public and cultural cash which the citizen has rights

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A quantitative, descriptive, cross-sectional and retrospective study, using technical procedures of document consultation from secondary sources and health household survey with application form for face to face inter views, with the assent nº.039/2011 from the Ethics Committee of the Federal University of Rio Grande do Norte. The aim of this study was to analyze the cervix cancer control in the area47 of the Health Family Centre Nova Natal II. The cancer cervix is the second most common cancer among women worldwide. In Brazil screening for early detection and treatment of disease has been poorly done and follow-up to reduce mortality has not been executed. From a total of1170women belonging to area 47, who under went screening by the Pap test in the period from 2005 to 2010,was elected a sample of 38 women with positive cervical changes, over 18 years old. The calculation of frequency analysis of socio demographic and clinical and epidemiological selected variables with the results of cervical changes, using the X2 test and taking as significance level of p<0.05 was not statistically significant. The predominant age range was 25 to 64 years (68.9%), most no white women (60.5%), predominantly with primary education (57.9%), most married (68.4%) and housewives (68.4%) with early age of sexual activity (86.8%), the minority smokers (13.2%), with a sexual partner (36.8%). At the time of interview, 42.1% of the women voiced complaint of discharge, while only 2.6% reported bleeding. In relation to the occurrence of STDs (including HPV), 10.5% of women reported being a carrier. The use of oral contraceptives was 32.3% of women, from 2 to 4 years (44.4%). The result of the last screening test performed, showed prevalence of immature squamous metaplasia (55.3%), followed by intraepithelial low- grade lesion (including the cytopathologic HPV effect and cervical intra epithelial neoplasia grade I) (31.6%); intraepithelial high-grade lesion (including cervical intraepithelial neoplasia grade II and III) (7.9%), atypical squamous non neoplastic cells (5.3%). There was no squamous cell carcinoma and adenocarcinoma. Most women received information about the action that should be done after the last screening test result (55.3%), but how to perform follow, most women did not report having done so (55.3%). The follow-up group of women studied, with varying degrees of cervical abnormalities, should only be completed with the discharge by cure, established inconsecutive negative cytology, a goal that is not being achieved in the area 47 of the Health Family Centre of Nova Natal II

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The production of petroleum is frequently accomplished with great volumes of water, that it is carried of the underground with the oil. It is a challenge of the present century the development of technologies that allow the use of waste water for purposes that consume great amounts of water and don't demand as rigid as the one of the drinking water requirements. The solar distillation has been configuring as an alternative of clean technology for desalination of brine and saline. Besides causing the minimum possible damage to the environment, it takes advantage of an abundant and free energy source: the solar energy. That study aims to develop a Solar Distillator for treatment of the produced water of the oil wells, to obtain an efluent to use in agriculture and vapor generation. The methodology for collection, conservation and analysis of the physical-chemical parameters obeyed the norms in APHA (1995). The sampling was of the composed type. Experiments were accomplished in the solar distillation pilot and simulation in thermostatic bathing. The operation was in batch system and for periods of 4, 6 and 12 h. The developed Distillator is of the type simple effect of two waters. It was still tested two inclination angles for covering; 20º and 45º. The Distillator presented minimum of 2,85 L/m2d revenues and maximum of 7,14 L/m2d. The removals of salts were great than 98%. The removal of TOC in the simulation was great than 90%. In agreement with the data of energy and mass balance, it was verified that the developed solar Distillator presented compatible revenues with those found in literature for similar types. It can be inferred that the obtained distilled water assists to the requirements CONAMA in almost all the points and could be used for irrigation of cultures such as cotton and mamona. As the distilled water has characteristics of fresh water it can be used in the generation of vapor

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Actually, surveys have been developed for obtaining new materials and methodologies that aim to minimize environmental problems due to discharges of industrial effluents contaminated with heavy metals. The adsorption has been used as an alternative technology effectively, economically viable and potentially important for the reduction of metals, especially when using natural adsorbents such as certain types of clay. Chitosan, a polymer of natural origin, present in the shells of crustaceans and insects, has also been used for this purpose. Among the clays, vermiculite is distinguished by its good ion exchange capacity and in its expanded form enhances its properties by greatly increasing its specific surface. This study aimed to evaluate the functionality of the hybrid material obtained through the modification of expanded vermiculite with chitosan in the removal of lead ions (II) in aqueous solution. The material was characterized by infrared spectroscopy (IR) in order to evaluate the efficiency of modification of matrix, the vermiculite, the organic material, chitosan. The thermal stability of the material and the ratio clay / polymer was evaluated by thermogravimetry. To evaluate the surface of the material was used in scanning electron microscopy (SEM) and (BET). The BET analysis revealed a significant increase in surface area of vermiculite that after interaction with chitosan, was obtained a value of 21, 6156 m2 / g. Adsorption tests were performed according to the particle size, concentration and time. The results show that the capacity of removal of ions through the vermiculite was on average 88.4% for lead in concentrations ranging from 20-200 mg / L and 64.2% in the concentration range of 1000 mg / L. Regarding the particle size, there was an increase in adsorption with decreasing particle size. In fuction to the time of contact, was observed adsorption equilibrium in 60 minutes with adsorption capacity. The data of the isotherms were fitted to equation Freundlich. The kinetic study of adsorption showed that the pseudo second- order model best describes the adsorption adsorption, having been found following values K2=0,024 g. mg-1 min-1and Qmax=25,75 mg/g, value very close to the calculated Qe = 26.31 mg / g. From the results we can conclude that the material can be used in wastewater treatment systems as a source of metal ions adsorbent due to its high adsorption capacity

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The oil industry, experiencing a great economic and environmental impact, has increasingly invested in researches aiming a more satisfactory treatment of its largest effluent, i.e., produced water. These are mostly discarded at sea, without reuse and after a basic treatment. Such effluent contains a range of organic compounds with high toxicity and are difficult to remove, such as polycyclic aromatic hydrocarbons, salts, heavy metals, etc.. The main objective of this work was to study the solar distillation of produced water pre-treated to remove salts and other contaminants trough of a hybrid system with a pre-heater. This developed apparatus was called solar system, which consists of a solar heater and a conventional distillation solar still. The first device consisted of a water tank, a solar flat plate collector and a thermal reservoir. The solar distillator is of simple effect, with 1m2 of flat area and 20° of inclination. This dissertation was divided in five steps: measurements in the solar system, i.e. temperatures and distillate flow rate and weather data; modeling and simulation of the system; study of vapor-liquid equilibrium of the synthetic wastewater by the aqueous solution of p-xylene; physical and chemical analyses of samples of the feed, distillate and residue, as well as climatology pertinent variables of Natal-RN. The solar system was tested separately, with the supply water, aqueous NaCl and synthetic oil produced water. Temperature measurements were taken every minute of the thermal reservoir, water tank and distillator (liquid and vapor phases). Data of solar radiation and rainfall were obtained from INPE (National Institute for Space Research). The solar pre-heater demonstrated to be effective for the liquid systems tested. The reservoir fluid had an average temperature of 58°C, which enabled the feed to be pre-heated in the distillator. The temperature profile in the solar distillator showed a similar behavior to daily solar radiation, with temperatures near 70°C. The distillation had an average yield of 2.4 L /day, i.e., an efficiency of 27.2%. Mathematical modeling aided the identification of the most important variables and parameters in the solar system. The study of the vapor-liquid equilibrium from Total Organic Carbon (TOC) analysis indicated heteroazeotropia and the vapor phase resulted more concentrated in p-xylene. The physical-chemical analysis of pH, conductivity, Total Dissolved Solids (TDS), chlorides, cations (including heavy metals) and anions, the effluent distillate showed satisfactory results, which presents a potential for reuse. The climatological study indicates the region of Natal-RN as favorable to the operation of solar systems, but the use of auxiliary heating during periods of higher rainfall and cloud cover is also recommended

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In wastewater treatment, activated sludge systems have been a technology widely applied as secondary treatment. During this step, which has a strong biological aspect, it is necessary to introduce oxygen supply for the maintenance of metabolic activity of the bacteria through the aerators. Aeration devices are responsible for most of the energy consumption in this stage. In this background, the influence of three aeration intensities (atmospheric air flow 3.5, 7.0 and 10.5 L.min-1) and the concentration of dissolved oxygen (DO) on the dimension of activated sludge flocs as well as on the efficiency of organic matter removal were assessed using a traditional activated sludge system which was fed with synthetic domestic wastewater. Samples were taken weekly from the three units that make up the system feed, aeration and storage tank in order to verify the Chemical Oxygen Demand (COD). It was established the process efficiency through a comparison between the initial and final COD. Besides the parameters already mentioned, this monitoring work on activated sludge batch system was also observed by Mixed Liquor Suspend Solids (MLSS), Volatile Suspend Solids (VSS), pH and temperature measures. The results have showed a maximum removal efficiency around 75% in the first aeration sequence and approximately 85% for the second and third one. For the first aeration, the DO concentration remained higher than 3.0 mg.L-1 and a diameter range from 10 to 60 μm was observed. In the second e third sequence, the DO concentration remained higher than 4.0 mg.L-1 with a diameter range of 10 until 200 μm. Although the sequence 1 and 2 have presented similar performances for organic matter removal, the sequence 2 promoted a regular floc size distribution and with lower values of Sludge Volumetric Index (SVI) meaning a better flocculating ability. In addition, the results reaffirmed what the literature has reported: higher DO concentrations produce flocs with greater dimensions

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This work study of solar distillation feasibility in effluent of petroleum industry: produced water, making possible your reuse for irrigation of oleaginous cultures or fodder crops or in steam generation, as well the transport phenomena involved. The methodology for development of this project was to characterize the effluent to be treated and to accomplish physical and chemical analysis in the distilled, to build distillation equipment, concomitant operation of both equipments and implementation of data processing and economical evaluation. The methodology used for all parameters is outlined in APHA (1998) and sampling of the type compound. The feeding of distillation equipment was performed with treated effluent from UTPF of Guamaré. The temperature was monitored throughout the distillers and during the time of operation. The distillers feed occur, as a rule, for sifon. The distillers were operated by a period of 17 months between July 2007 and February 2009, in which 40 experiments were performed. The radiation and temperature datas were acquired in the INPE s site and the temperature inside of the distillers was registered by DATALOGGER Novus. The rates of condensation (mL / min) were determined by measuring of the flow in a graduate test tube of 10 mL and a chronometer. We used two simple solar effect distillers of passive type with different angles in coverage: 20 ° and 45 °. The results obtained in this study and the relevant discussions are divided into six topics: sample characterization and quality of distilled; construction of distillers; operation (data, temperature profile), climatic aspects, treatment of data and economical analysis. Results obtained can be inferred that: the energy loss by the adoption of vessel glass was not significant, however, complicates the logistics of maintenance the equipment on a large scale. In the other hand, the surface of the tub with a glass shield on the equipment deterioration, both devices showed similar performance, so there is not justified for use of equipment 450. With regard to the climatological study it was verified that the Natal city presents monthly medium radiation varying in a range between 350 and 600 W/m2, and medium of wind speed of 5 m / s. The medium humidity is around 70% and rainfall is very small. The regime of the system is transient and although it has been treated as a stationary system shows that the model accurately represents the distillers system's 20 degrees. The quality of the distilled with regard to the parameters evaluated in this study is consistent with the Class 3 waters of CONAMA (Resolution 357). Therefore we can conclude that solar distillation has viability for treat oilfield produced water when considered the technical and environmental aspects, although it is not economically viable

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During production of oil and gas, there is also the production of an aqueous effluent called produced water. This byproduct has in its composition salts, organic compounds, gases and heavy metals. This research aimed to evaluate the integration of processes Induced Air Flotation (IAF) and photo-Fenton for reducing the Total Oils and Greases (TOG) present in produced water. Experiments were performed with synthetic wastewater prepared from the dispersion of crude oil in saline solution. The system was stirred for 25 min at 33,000 rpm and then allowed to stand for 50 min to allow free oil separation. The initial oil concentration in synthetic wastewater was 300 ppm and 35 ppm for the flotation and the photo-Fenton steps, respectively. These values of initial oil concentration were established based on average values of primary processing units in Potiguar Basin. The processes were studied individually and then the integration was performed considering the best experimental conditions found in each individual step. The separation by flotation showed high removal rate of oil with first-order kinetic behavior. The flotation kinetics was dependent on both the concentration and the hydrophilic-lipophilic balance (HLB) of the surfactant. The best result was obtained for the concentration of 4.06.10-3 mM (k = 0.7719 min-1) of surfactant EO 2, which represents 86% of reduction in TOG after 4 min. For series of surfactants evaluated, the separation efficiency was found to be improved by the use of surfactants with low HLB. Regarding the TOG reduction step by photo-Fenton, the largest oil removal reached was 84% after 45 min of reaction, using 0.44 mM and 10 mM of ferrous ions and hydrogen peroxide, respectively. The best experimental conditions encountered in the integrated process was 10 min of flotation followed by 45 min of photo-Fenton with overall TOG reduction of 99%, which represents 5 ppm of TOG in the treated effluent. The integration of processes flotation and photo-Fenton proved to be highly effective in reducing TOG of produced water in oilfields

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One of the waste generated during the drilling of oil wells are gravel which are impregnated of drilling fluid. This residue consists of highly toxic chemicals, including toxic metals. This study suggests an alternative process to the treatment of this waste, by incorporating it the form of raw material in the ceramic matrix , and by solidification and stabilize the metals present, Aluminum (Al), Iron (Fe), Manganese (Mn) and Zinc (Zn). The raw materials were characterized by the techniques of X ray fluorescence (FRX), X ray diffraction (DRX), laser granulometry (GL), thermogravimetry (TG) and differential thermal analysis (ADT). To evaluate the percentage of gravel effect the environmental and technological properties were obtained from formulations containing 0, 10 and 20 % by weight of gravel in the ceramic matrix. After sintering at temperatures 1080, 1120 and 1160 °C, the samples were tested for water absorption, the linear shrinkage firing, voltage of rupture and solubility. The results obtained showed that the stabilization by solidification, is a viable alternative to safe disposal of waste drilling. Ceramics products can be used in the manufacture of solid bricks

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La enseñanza de problemas se ha investigado en la didáctica de las ciencias naturales como un medio importante para desarrollar el aprendizaje de los conocimientos científicos y la formación de competencias básicas. Dada la importancia de los libros de texto para la enseñanza de la ciencia, con el fin de verificar el enfoque de la enseñanza con problemas en los libros de química, se procedió a una investigación realizada en las obras aprobadas en PNLD 2012, basado en el método de Análisis de Contenido. Se analizó el contenido de la estructura atómica, como marco teórico la perspectiva de la enseñanza problémica, basada en el materialismo histórico y dialéctico. Metodológicamente la investigación presenta un carácter cualitativo. Los resultados del análisis de contenido corroboraron la cuestiones de estudio iniciales relacionadas con la explicación centrándose en los problemas, lo que permitió inferir la elaboración de una Unidad Didactica basada en los métodos problémicos para la enseñanza de los modelos atómicos por la exposición problémica, la conversación heurística y la busca parcial, como forma de aproximar los estudiantes a la naturaleza de las ciencias naturales y contribuir al desarrollo de actitudes positivas en el aprendizaje de la química