34 resultados para Ponto fixo
Resumo:
Inclusion of students with disabilities is a recent case that has been discussed in school contexts, but the current policy of inclusion for access and retention of students in higher education is still a problem face there is much to do, therefore, are incipient studies in which this student body is involved. Accordingly, what is happening is that the most studies deal with on these students and little is said about them. For inclusive education thus the institution should prepare to receive students, having as one of its premises their point of views about what actually experience aiming at promoting education for all. Therefore, this study deals with the process of inclusion of students with disabilities regularly enrolled in undergraduate courses at the Universidade Federal do Rio Grande do Norte - UFRN.They were used the assumptions of qualitative research enabled by the case study method and semi-structured interviews. It has been analyzed by guiding actions and teaching practices, under the views of disabled students and teachers, the conditions of access and permanence offered by UFRN. Twelve students with physical, visual, hearing disabilities participated and five teachers from the acedemic centers that in academic year 2008 taught to these students. For data analysis it was used the technique of content analysis. It was extracted two themes: access and retention of students with disabilities in UFRN, in which emerged the categories described and analyzed in the course of this work. The results show the difficulties of access and retention of students with disabilities within the UFRN, such as attitudinal, pedagogical and architectural barriers. However, as it has also turned out, initial advances in the quest for achieving more effective actions to guarantee access and permanence of these students in UFRN. It has concluded that the scope for the exercise of citizenship in the pupils with disabilities who need this Higher Education Institution has an inclusive education Project, wide and consolidated, for the actions undertaken by the Ministry of Education - MEC, by itself, are not guaranteed to all students due to mobility, autonomy and security. It has hoped this work will bring benefits for new studies to develop features that were located, but were not our focus, because then the UFRN may advance the inclusive process of disabled students
Resumo:
This work presents an analysis of the method of intervention used in the craft of design by SEBRAE in Rio Grande do Norte under the viewpoint of the actors involved, especially the craftsmen and design consultants. The research methodology used was based on the ergonomic work analysis - AET, applying observational techniques and interactive. Data tabulated from the matrix to include comments were analyzed in order to allow the generation of qualitative and quantitative information. The results of this research allow us to affirm that for the process of innovation through the design of intervention are satisfactory for all involved, it is necessary that the bonds of interaction are established and the joint actions in the innovation process to bear fruit in favor sustainability of artisan groups
Resumo:
The nonionic surfactants are composed of substances whose molecules in solution, does not ionize. The solubility of these surfactants in water due to the presence of functional groups that have strong affinity for water. When these surfactants are heated is the formation of two liquid phases, evidenced by the phenomenon of turbidity. This study was aimed to determine the experimental temperature and turbidity nonilfenolpoliethoxyled subsequently perform a thermodynamic modeling, considering the models of Flory-Huggins and the empirical solid-liquid equilibrium (SLE). The method used for determining the turbidity point was the visual method (Inoue et al., 2008). The experimental methodology consisted of preparing synthetic solutions of 0,25%, 0,5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12,5%, 15%, 17% and 20% by weight of surfactant. The nonionic surfactants used according to their degree of ethoxylation (9.5, 10, 11, 12 and 13). During the experiments the solutions were homogenized and the bath temperature was gradually increased while the turbidity of the solution temperature was checked visually Inoue et al. (2003). These temperature data of turbidity were used to feed the models evaluated and obtain thermodynamic parameters for systems of surfactants nonilfenolpoliethoxyled. Then the models can be used in phase separation processes, facilitating the extraction of organic solvents, therefore serve as quantitative and qualitative parameters. It was observed that the solidliquid equilibrium model (ESL) was best represented the experimental data.
Resumo:
Supported catalysts of CuCl2 on sílica were used in the methane oxychlorination reaction. The materials were synthesized by the ion exchange technique in a basic solution, using a copper-ammonia complex with 3 and 6 % of nominal copper loading. The materials where characterized by thermogravimetry (TG), X-ray Fluorescence Spectroscopy (XRF), Temperature Programmed Reduction (TPR), Scanning Electron Microscopy with X-ray microanalysis (SEM/EDS), BET specific area and pore distribution. The characterization confirms the presence of copper on the support surface, concluding that the ion exchange technique was adequate in the catalyst synthesis. For the reaction test, an oxychlorination bench scale unit was employed. The tests were carried at 673 and 773 K. The results showed the influence of temperature and catalyst copper content on the oxychlorination of methane reaction
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This dissertation aims to assess the representativeness of the manual chilled mirror analyzer (model II Chanscope 13-1200-CN-2) used for the determination of condensed hydrocarbons of natural gas compared to the indirect methods, based on thermodynamic models equation of state. Additionally, it has been implemented in this study a model for calculating the dew point of natural gas. The proposed model is a modification of the equation of state of Peng-Robinson admits that the groups contribution as a strategy to calculate the binary interaction parameters kij (T) temperature dependence. Experimental data of the work of Brown et al. (2007) were used to compare the responses of the dew point of natural gas with thermodynamic models contained in the UniSim process simulator and the methodology implemented in this study. Then two natural gas compositions were studied, the first being a standard gas mixture gravimetrically synthesized and, second, a mixture of processed natural gas. These experimental data were also compared with the results presented by UniSim process simulator and the thermodynamic model implemented. However, data from the manual analysis results indicated significant differences in temperature, these differences were attributed to the formation of dew point of water, as we observed the appearance of moisture on the mirror surface cooling equipment
Resumo:
Studies show the great influence of free radicals and other oxidants as responsible for aging and degenerative diseases. On the other hand, the natural phenolic compounds has shown great as antioxidants to inhibit lipid peroxidation and lipoxygenase in vitro. Among these, is highlighted trans-resveratrol ( 3,5,4 `- trihydroxystilbene ) phenolic compound , characterized as a polyphenol stilbene class. The vegetables popularly known as "Azedinha" (Rumex Acetosa) has trans-resveratrol in its composition and from this, the present work aimed to study on the supercritical extraction and conventional extraction (Soxhlet and sequential) in roots of Rumex Acetosa, evaluating the efficiency of extractive processes, antioxidant activity, total phenolic content and quantification of trans-resveratrol contained in the extracts. Extractions using supercritical CO2 as solvent, addition of co-solvent (ethanol) and were conducted by the dynamic method in a fixed bed extractor. The trial met a 23 factorial design with three replications at the central point, with the variable reply process yield and concentration of trans-resveratrol and pressure as independent variables, temperature and concentration of co-solvent (% v/v). Yields ( mass of dry extract / mass of raw material used ) obtained from the supercritical extraction ranged from 0,8 to 7,63 % , and the best result was obtained at 250 bar and 90 °C using the co-solvent 15% ethanol (% v/v). The value was calculated for YCER a flow rate of 1,0 ± 0,17 g/min resulting in 0,0469 CO2 ( g solute / g solvent ). The results of the mass yield varied between conventional extractions 0,78 % ( hexane) and 9,97 % (ethanol). The statistical model generated from the data of the concentration of trans-resveratrol performed as meaningful and predictive for a 95% confidence. GC analysis on HPLC (High Performance Liquid Chromatography), transresveratrol was quantified in all extracts and concentration values ranged between 0,0033 and 0,42 ( mg / g extract) for supercritical extracts and between 0,449 and 17,046 (mg / g extract) to conventional extractions and therefore, the Soxhlet extraction with ethanol for more selective trans-resveratrol than the supercritical fluid. Evaluation of antioxidant (radical method to sequester 2,2- diphenyl-1- picryl - hydrazyl - DPPH) the supercritical extracts resulted in EC50 values (concentration effective to neutralize 50% of free radicals) of between 7,89 and 18,43 mg/mL , while resulting in a Soxhlet extraction with EC50 values in the range of 6,05 and 7,39 mg/mL. As for quantification of the phenolic compounds (Method Spectrophotometer Folin-Ciocalteau) the supercritical extracts resulted in values between 85,3 and 194,79 mg GAE / g extract, whereas values derived from the Soxhlet extract resulted in values between 178,5 and 237,8 mg GAE / g extract. The high antioxidant activity can not be attributed solely to the presence of phenolic compounds, but the presence of other antioxidants in the existing Rumex acetosa
Resumo:
This research aims to identify the process of appropriation of audio visual (in digital video) for collective symbolic production (participatory video practice that expresses popular culture) in a socio-cultural context where the minorities are. Therefore, we based this study on the students‟ experience of the film and video workshops held by Cinema para Todos (Culture Point Cine for All), in Natal, RN. Culture Point is the basis of the project Programa Nacional de Cultura, Educação e Cidadania Cultura Viva (National Program of Culture, Education and Citizenship - Living Culture) of the Brazilian Ministry of Culture. In 2010, the Cine for All developed three film and video workshops in the state of Rio Grande do Norte (Northeastern of Brazil), in the municipalities of Açu, Lajes and São Gonçalo do Amarante, within a public policy project of socio-cultural inclusion. These three workshops are the focus of this empirical investigation. To support the analysis of this research we consider that the spaces of workshops are sites of the social practices origin, assuming they show the development of the changes of actions that generate new practices. In this socio-cultural context the students as interlocutors process the communicative culture mediation, where come from the logics of action (using digital video) to become a mediatic practice (video auto ethnographic). With the overall goal set and the field of investigative action delimited we considered the methodology of case study suitable for the observation of the object, because it is a phenomenon of modernity, occurring in a context of real life and with little or no control over events. Participant observation and interviews was also applied to this case study. The analytical theoretical support comes from the notion of mediation by Jesús Martín-Barbero and the concept of habitus by Pierre Bourdieu. The research found that a new way of communicating has been developing by this social group, and this reflects the technological change experienced by them. The auto ethnographic videos, short movies, reveal an allegorical trial of the mainstream media, because while they use the mainstream format, they rework the aesthetic, but without revising the history, in fact they proposing to retell the history of themselves full of colorful details and with richness of their forgotten popular culture.
Resumo:
The presence of fixed orthodontics appliances interfere on sanitation, allowing periodontal diseases to appear, despite the fact patients keep on visiting the dentist every month. This research aims to determine a protocol for the mechanical control of the dental biofilm performed by the professional. A protocol that was able to maintain the periodontal health of the patients under orthodontic treatment with fixed appliances, and in order to do so, it used a non-controlled, randomized and blind clinical essay. The sample involved 40 adolescents who were under the installation of fixed orthodontics appliances and it was divided in three groups, as follows: monthly controlled group (group 1) composed of 11 patients, the quarterly controlled group (group 2) with 16 patients and the semestrial controlled group (group 3) with 13 patients. For data collection, an interview and clinical exams with probing depth measurement, quantity of keratinized mucosa, Gingival Index and the Plaque Index were used. On the initial exam all patients received brushing guidelines as well as the professional control of dental biofilm, with periodontal scaler, Robinson s brush and prophylactic paste. However, Group 1 returned every month for control procedures; Group 2 every three months and Group 3 after six months. The intervention had a six-month duration (for all the three groups), when all the exams were repeated by another examiner who did not know which group each patient was inserted in. Finally, the research concluded that despite the fact there is no statistically significant difference among the three groups, clinically the patients from the monthly group presented a better response to professional control, with less accumulation of dental biofilm and less rate of gingival inflammation. Thus, the mechanical control of the dental biofilm performed by the professional could not avoid gingival increase, characterized by the raise of probing depth measurement, neither the quantity of keratinized mucosa
Resumo:
Systemic lupus erythematous (SLE) is a chronic and auto-immune disease that can affect several systems of one´s body, including the nervous system, causing several clinical evidences, which can put in risk the person´s life. Although the illness could manifest itself at any age or sex, studies indicate higher incidence among women. Its etiology points to the combination of genetic, hormonal and environmental factors. Due to the disease´s complexity, it is evident that it affects all the person´s life as a whole and not only its organic dimension. It is believed that the signification attributed to all the process of sickening influences its treatment, as well as the person´s capacity to cope with the difficulties and implicit profits involved in the process.In this study, eight women who were affected by SLE were interviewed, with the aim of examining carefully the processes of signification as well as the generation of meanings which permeate these women´s sickening processes. The analysis of their speeches evidences distinct forms of giving meaning to the process, regardless of the time of the diagnosis. The fact that the disease is incurable was shocking to all the participants, and it demanded changes in their lives, in order to detain a relative control of their condition. The majority of the participants were able to deal with these modifications, since strategies have been created to face the difficulties and thus to preserve their social life, without damaging their health. However, some of the participants did not obtain strenght to cope with the disease, eventually developing a depressive state. It is observed that not only SLE has innumerable ways of manifestation, but the experience of the illness is very subjective and dynamic. There are also several ways of expressing this experience, according to the implications in the social, cultural and economic context where the participants are inserted. This ratifies the necessity of a interdisciplinary approach to embrace SLE complexity. (310 words, 1.610 characters)
Resumo:
Un conjunto de cambios viene siendo implantado en la Petrobrás procurando que sus unidades de negocios resulten más modernas y competitivas para atender las necesidades del mercado. Dentro de esta perspectiva, un nuevo régimen de trabajo, denominado turno fijo , ha sido implantado en dos activos de producción de la provincia de Rio Grande do Norte. Tal situación originó varios reclamos de los petroleros y, consecuentemente, el interés del SINDIPETRO-RN en obtener una evaluación más precisa de las consecuencias de los mismos. Este estudio, realizado a partir de la demanda sindical de esos trabajadores, ha tenido como objetivo central analizar los efectos del turno fijo sobre la salud mental de los operadores de producción, actualmente lotados en los referidos activos. El estudio ha sido realizado con 39 operadores que representan el 82,9% de la población objeto de este estudio. La muestra ha sido homogénea en cuanto al género, grado de instrucción, edad y tiempo de servicio en la compañía, lo que ha posibilitado un mayor control de las variables y un estudio comparativo entre los dos activos. Para el desarrollo del estudio, se han aplicado los siguientes instrumentos de colecta de datos: una escala de medida probada y validada (QSG-12), un cuestionario abierto, entrevistas individuales y una ficha socio-demográfica. Las respuestas del cuestionario abierto han sido categorizadas mediante la aplicación de análisis de contenido. Los resultados de ese tratamiento y las respuestas del QSG-12 han sido registradas en la forma de banco de datos del SPSS for Windows (Statical Package for social sciense for Windows) para luego procederse con el desarrolllo de los análisis estadísticos. Los principales resultados encontrados en el estudio han sido que la mitad de los participantes de la muestra han presentado resultados de deteriorización de la autoeficacia más elevado que 1,44 (un una escala de 0 a 3) y, en tensión emocional y depresión, el resultado es más elevado que 1,67; la mayoría se da cuenta del aumento de carga de trabajo, revela acentuado sufrimiento con el distanciamiento de la familia, y 58,8% presenta enfermedades psicosomáticas crónicas. La percepción de los operadores sobre el turno fijo e el análisis de éste, conforme el modelo vitamínico de Warr, conducen a la conclusión de que el turno fijo es uno de los factores que está influyendo negativamente en la salud mental de esos trabajadores
Resumo:
Alkyl polyethoxylates are surfactants widely used in vastly different fields, from oil exploitation to pharmaceutical applications. One of the most interesting characteristics of these surfactants is their ability to form micellar systems with specific geometry, the so-called wormlike micelle. In this work, microemulsions with three distinct compositions (C/T = 40 %, 30 % and 25 %) was used with contain UNITOL / butanol / water / xylene, cosurfactant / surfactante (C/S) ratio equal to 0,5. The microemulsion was characterized by dynamic light scattering (DLS), capillary viscometry, torque rheometry and surface tensiometry experiments carried out with systems based on xylene, water, butanol (cosurfactant) and nonaethyleneglycolmonododecyl ether (surfactant), with fixed surfactant:cosurfactant:oil composition (with and without oil phase) and varying the overall concentration of the microemulsion. The results showed that a transition from wormlike micelles to nanodrops was characterized by maximum relative viscosity (depending on how relative viscosity was defined), which was connected to maximum effective diameter, determined by DLS. Surface tension suggested that adsorption at the air water interface had a Langmuir character and that the limiting value of the surfactant surface excess was independent of the presence of cosurfactant and xylene. The results of the solubilization of oil sludge and oil recovery with the microemulsion: C/S = 40%, 30% and 25% proved to be quite effective in solubilization of oil sludge, with the percentage of solubilization (%solubilization) as high as 92.37% and enhanced oil recovery rates up to 90.22% for the point with the highest concentration of active material (surfactant), that is, 40%.
Resumo:
This work presents JFLoat, a software implementation of IEEE-754 standard for binary floating point arithmetic. JFloat was built to provide some features not implemented in Java, specifically directed rounding support. That feature is important for Java-XSC, a project developed in this Department. Also, Java programs should have same portability when using floating point operations, mainly because IEEE-754 specifies that programs should have exactly same behavior on every configuration. However, it was noted that programs using Java native floating point types may be machine and operating system dependent. Also, JFloat is a possible solution to that problem
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Produced water is a major problem associated with the crude oil extraction activity. The monitoring of the levels of metals in the waste is constant and requires the use of sensitive analytical techniques. However, the determination of trace elements can often require a pre-concentration step. The objective of this study was to develop a simple and rapid analytical method for the extraction and pre-concentration based on extraction phenomenon cloud point for the determination of Cd, Pb and Tl in produced water samples by spectrometry of high resolution Absorption source continues and atomization graphite furnace. The Box Behnken design was used to obtain the optimal condition of extraction of analytes. The factors were evaluated: concentration of complexing agent (o,o-dietilditilfosfato ammonium, DDTP), the concentration of hydrochloric acid and concentration of surfactant (Triton X -114). The optimal condition obtained through extraction was: 0,6% m v-1 DDTP, HCl 0,3 mol L-1 and 0,2% m v-1 of Triton X - 114 for Pb; 0,7% m v-1 DDTP, HCl 0,8 mol L-1 and 0,2% m v-1 Triton X-114 for Cd. For Tl was evidenced that best extraction condition occurs with no DDTP, the extraction conditions were HCl 1,0 mol L-1 e 1,0% m v-1 de Triton X - 114. The limits of detection for the proposed method were 0,005 µg L-1 , 0,03 µg L-1 and 0,09 µg L-1 to Cd, Pb and Tl, Respectively. Enrichment factors Were greater than 10 times. The method was applied to the water produced in the Potiguar basin, and addition and recovery tests were performed, and values were between 81% and 120%. The precision was expressed with relative standard deviation (RSD) is less than 5%
Resumo:
Sulfur compounds emissions have been, on the late years, subject to more severe environmental laws due to its impact on the environment (causing the acid rain phenomena) and on human health. It has also been object of much attention from the refiners worldwide due to its relationship with equipment’s life, which is decreased by corrosion, and also with products’ quality, as the later may have its color, smell and stability altered by the presence of such compounds. Sulfur removal can be carried out by hydrotreating (HDT) which is a catalytic process. Catalysts for HDS are traditionally based on Co(Ni)-Mo(W)/Al2O3. However, in face of the increased contaminants’ content on crude oil, and stricter legislation on emissions, the development of new, more active and efficient catalysts is pressing. Carbides of refractory material have been identified as potential materials for this use. The addition of a second metal to carbides may enhance catalytic activities by increasing the density of active sites. In the present thesis Mo2C with Co addition was produced in a fixed bed reactor via gas-solid reaction of CH4 (5%) and H2(95%) with a precursor made of a mix of ammonium heptamolybdate [(NH4)6[Mo7O24].4H2O] and cobalt nitrate[Co(NO3)2.6H2O] at stoichiometric amounts. Precursors’ where analyzed by XRF, XRD, SEM and TG/DTA. Carboreduction reactions were carried out at 700 and 750°C with two cobalt compositions (2,5 and 5%). Reaction’s products were characterized by XRF, XRD, SEM, TOC, BET and laser granulometry. It was possible to obtain Mo2C with 2,5 and 5% cobalt addition as a single phase at 750°C with nanoscale crystallite sizes. At 700°C, however, both MoO2 and Mo2C phases were found by XRD. No Co containing phases were found by XRD. XRF, however, confirmed the intended Co content added. SEM images confirmed XRD data. The increase on Co content promoted a more severe agglomeration of the produced powder. The same effect was noted when the reaction temperature was increased. The powder synthesized at 750°C with 2,5% Co addition TOC analysis indicated the complete conversion from oxide material to carbide, with a 8,9% free carbon production. The powder produced at this temperature with 5% Co addition was only partially converted (86%)
Resumo:
The textile sector is one of the main contributors to the generation of industrial wastewaters due to the use of large volumes of water, which has a high organic load content. In these, it is observed to the presence of dyes, surfactants, starch, alcohols, acetic acid and other constituents, from the various processing steps of the textiles. Hence, the treatment of textile wastewater becomes fundamental before releasing it into water bodies, where they can cause disastrous physical-chemical changes for the environment. Surfactants are substances widely used in separation processes and their use for treating textile wastewaters was evaluated in this research by applying the cloud point extraction and the ionic flocculation. In the cloud point extraction was used as surfactant nonylphenol with 9.5 ethoxylation degree to remove reactive dye. The process evaluation was performed in terms of temperature, surfactant and dye concentrations. The dye removal reached 91%. The ionic flocculation occurs due to the presence of calcium, which reacts with anionic surfactant to form insoluble surfactants capable of attracting the organic matter by adsorption. In this work the ionic flocculation using base soap was applied to the treatment of synthetic wastewater containing dyes belonging to three classes: direct, reactive, and disperse. It was evaluated by the influence of the following parameters: surfactant and electrolyte concentrations, stirring speed, equilibrium time, temperature, and pH. The flocculation of the surfactant was carried out in two ways: forming the floc in the effluent itself and forming the floc before mixing it to the effluent. Removal of reactive and direct dye, when the floc is formed into textile effluent was 97% and 87%, respectively. In the case where the floc is formed prior to adding it to the effluent, the removal to direct and disperse dye reached 92% and 87%, respectively. These results show the efficience of the evaluated processes for dye removal from textile wastewaters.