Otimização do processo de flotação de emulsão óleo/água através do planejamento fatorial completo

In recent decades, the generation of solid and liquid waste has increased substantially due to increased industrial activity that is directly linked to economic growth. For that is the most efficient process, it is inevitable generation of such wastes. In the oil industry, a major waste generated in oil exploration is produced water, which due to its complex composition and the large amount generated, has become a challenge, given the restrictions imposed by environmental laws regarding their disposal, making if necessary create alternatives for reuse or treatment in order to reduce the content of contaminants and reduce the harmful effects to the environment. This water can be present in free form or emulsified with the oil, when in the form of an emulsion of oil-water type, it is necessary to use chemicals to promote the separation and flotation is the treatment method which has proved to be more efficient, for it can remove much of the emulsified oil when compared to other methods. In this context, the object of this work was to study the individual effects and interactions of some physicochemical parameters of operations, based on previous work to a flotation cell used in the separation of synthetic emulsion oil / water in order to optimize the efficiency of the separation process through of the 24 full factorial design with center point. The response variables to evaluate the separation efficiency was the percentage of color and turbidity removal. The independent variables were: concentration of de-emulsifying, oil content in water, salinity and pH, these being fixed, minimum and maximum limits. The analysis of variance for the equation of the empirical model, was statistically significant and useful for predictive purposes the separation efficiency of the floater with R2 > 90%. The results showed that the oil content in water and the interaction between the oil content in water and salinity, showed the highest values of the estimated effects among all the factors investigated, having great and positive influence on the separation efficiency. By analyzing the response surface was determined maximum removal efficiency above 90% for both measured for turbidity as a measure of color when in a saline medium (30 g/L), the high oil concentrations (306 ppm) using low concentrations of de-emulsifying (1,1 ppm) and at pH close to neutral

Avaliação cinética e potencial do Nb2O5 obtido a partir de um complexo de nióbio para formação do oleato de metila através da reação de esterificação do ácido oleico

Among the heterogeneous catalysts materials made from niobium show up as an alternative to meet the demand of catalysts for biodiesel production. This study aims to evaluate the potential of a heterogeneous catalyst derived from a complex of niobium in the reaction of methyl esterification of oleic acid. The catalyst was synthesized after calcination at different temperatures of a niobium complex ((NH4)3[NbO(C2O4)3].H2O) generating a niobium oxide nanostructure with a different commercial niobium oxide used to synthesize the complex. The commercial niobium oxide, the complex niobium and niobium catalyst were characterized by thermogravimetry (TG and DTA), surface area analysis (BET), scanning electron microscopy (SEM) and X-ray diffraction (XRD), showing the catalyst has researched morphological and crystallographic indicating a catalytic potential higher than that of commercial niobium oxide characteristics. Factorial with central composite design point, with three factors (calcination temperature, molar ratio of alcohol/oleic acid and mass percentage of catalyst) was performed. Noting that the optimal experimental point was given by the complex calcination temperature of 600°C, a molar ratio alcohol/oleic acid of 3.007/1 and the catalyst mass percentage of 7.998%, with a conversion of 22.44% oleic acid in methyl oleate to 60 min of reaction. We performed a composite linear and quadratic regression to determine an optimal statistical point of the reaction, the temperature of calcination of the complex at 450°C, the molar ratio of alcohol/oleic acid 3.3408/1 and mass percentage of catalyst of 7.6833% . Kinetic modeling to estimate parameters for heterogeneous catalysis it set well the experimental results with a final conversion of 85.01% with 42.38% of catalyst and without catalyst at 240 min reaction was performed. Allowing to evaluate the catalyst catalytic studied has the potential to be used in biodiesel production

A percepção dos docentes da UFRN sobre o programa de apoio a planos de reestruturação e ampliação das universidades federais - REUNI

In recent decades higher education in Brazil has gone through several changes. The Programa de Reestruturação e Expansão das Universidades Federais REUNI has been the greatest overhaul performed by the government in public universities in the last years. REUNI is presented as the biggest reform in tertiary education in contemporary times, having as the main goal a gradual increase in the average rate of conclusion in live learning graduation courses up to 90%, as well as a rate expansion of graduating students in face to face classes per professor. This research aims at studying the perception of professors from UFRN concerning the REUNI program in execution from 2008 until 2012. The study seeks to understand how professors evaluate the program and what the dimensions that most influence in this evaluation are. The study made use of a research tool (survey) which was sent through the internal system of the university, SIGAdmin, to all professors of superior teaching from UFRN. The answers generated by the survey were processed using SPSS statistical software (Statistical Package for Social Science). Factorial Analysis and Multiple Linear Regression were used as an analysis technique. 180 answers were obtained, reaching all UFRN Centers and some academic units, as well as some campuses in the countryside of the state. Through the research was possible to analyze how professors from UFRN perceive the REUNI program implemented in the institution. The results point to the program approval by the professors. Statistical tests showed that the average values obtained in the Centers and academic units are basically the same. It was demonstrated that the extent that most influenced in the answers is linked to practical outcomes of the program, whereas the knowledge of REUNI goals was the least that impacted on the marks given to the program. Another dimension which influenced the perception of professors relates to the influence of REUNI in their activities. It was observed that professors from UFRN don t see REUNI as an impediment to them

Consequências da análise inadequada de um experimento fatorial 2k am parcelas subdivididas e sem replicação

Em experimentos com vários fatores em que alguns são mais difíceis de mudar que outros, pode ser inconveniente executar as provas do experimento em uma forma completamente aleatória, levando o pesquisador a criar naturalmente uma restrição na ordem de execução para poupar tempo ou reduzir os custos. Este tipo de restrição pode resultar em uma generalização do planejamento fatorial, conhecida como experimentos em parcelas subdivididas. Na prática, é comum executar um experimento em parcelas subdivididas e analisá-lo como se fosse completamente aleatorizado. O objetivo principal do trabalho é avaliar o impacto de analisar um experimento com restrição na aleatorização como completamente aleatorizado

Comparação entre metodologias de extração de HPAs em água utilizando um planejamento fatorial com quantificação no CG/EM

PAHs (Polycyclic Aromatic Hydrocarbons) are a group of organic substances which receive considerable attention because of the carcinogenic and mutagenic properties of some of them. It is therefore important to determine the PAHs in different environmental matrices. Several studies have shown the use of gas chromatography coupled to mass spectrometry as a technique for quantification of PAHs by presenting excellent detection limits. This study aimed to develop an analytical methodology for the determination of 16 PAHs listed by the USEPA, test two methods for extraction of PAHs in water from a 23 factorial design, quantify them through the analytical technique coupled to gas chromatography mass spectrometry (GC/MS) using the method developed, and finally apply the results in chemometrics. The sample was synthesized and subjected to tests of the 23 factorial design, which has the factors: the type of extraction technique (ultrasound and digester), the ratio solvent / sample (1:1 and 1:3) and the type of solvent (dichloromethane / hexane and acetone / dichloromethane). The responses of eight combinations of the factorial design were obtained from the quantification by external calibration in GC/MS. The quantification method was developed from an optimized adaptation of the USEPA Method 8270. We used the full scan mode as a way of acquiring the mass spectra of 16 PAHs. The time in which the samples were subjected to ultrasound was fixed at 10 min and held an investigation to establish the conditions of power and time in the digester. We had the best response in the investigation of the digester power of 100 watts and the time of six minutes. The factorial design of liquid-liquid extraction showed that the most representative factors were: the use of the digester as extraction technique, the ratio solvent / sample 1:1 and the use of a 1:1 mixture of dichloromethane / hexane as a solvent more suitable. These results showed that the 1:1 mixture of dichloromethane / hexane is an excellent mixture to recover the extraction of PAHs an aqueous sample using the microwave digester. The optimization of the method of separation, identification and quantification of PAHs in the GC/MS was valid for 16 PAHs present in each chromatogram of the samples

Relação das condições socioeconômicas com as condições de saúde bucal em capitais brasileiras

Despite the improvement of Brazilian s living conditions in recent decades, this improvement occurred in a polarized way between groups of better social position. Then, there is still a health inequity´s panorama in Brazil which encompasses the oral health state. This panorama instigated the attainment of this ecological study that aimed to evaluate the relationship of socioeconomic conditions, and public health policies with oral health status in Brazilian capitals. Thus, we performed factor analysis and linear regression using oral health indicators collected from SB Brasil 2010, of socioeconomic conditions from Brazilian Census 2010 and related to water´s supply fluoridation from SISAGUA. Factor analysis with indicators of living conditions revealed two common factors, economic deprivation and socio-sanitary condition. Economic deprivation showed statistically significant positive correlation with DMFT 12 years (p= 0,03) and mean missing teeth (p = 0,002) and negative correlation with caries-free population (p=0,012). Socio-sanitary negatively correlated with DMFT (p <0,0001) and a positive correlation with caries-free population (p = 0.002). Fluoridated water had a significant association with DMFT (p <0,0001), mean missing teeth (p <0,0001) and caries free population (p <0.0001). Multiple linear regression analysis for the DMFT of capital was estimated by socio-sanitary condition and fluoridation, adjusted by economic deprivation, whereas the model for the mean missing teeth was estimated only by fluoridation and economic deprivation, and finally the model the rate for the population free of caries in Brazilian capitals was estimated by economic and socio-sanitary status adjusted fluoridated water supply. Therefore, factors related to living conditions and public policies are intrinsically linked to tooth decay issues. Thus, actions, beyond dental care assistance, must be development to impact positively in social and economic conditions, especially, between the most vulnerable populations

Prevalência e fatores associados ao risco e a desnutrição em idosos institucionalizados

One of the most important problems in the elderly is a nutritional deficiency. Several physiological changes and the use of multiple drugs interfere with appetite, food intake and absorption of nutrients, which can lead to the risk and malnutrition in the elderly, especially among institutionalized. The present study aimed to evaluate the prevalence of malnutrition and risk for malnutrition and its associated factors in institutionalized elderly. The same can be characterized by the type individual, observational and cross-sectional. Obtaining the sample was through the records of individuals of long-stay institutions for the elderly in the city of Natal, RN. The elderly were evaluated through the Mini Nutritional Assessment (MNA) and triceps skinfold (TSF) and each senior or caregiver answered a questionnaire about information like type and dietary restrictions, accessibility to food, use of alcohol and tobacco, practice physical activity and appetite. Variables such as age, gender, education, marital status, time that the elderly living in the institution, the reason for the institutionalization and comorbidities were taken from the records of each senior. The frequency of food consumption of various food groups was assessed from the questionnaire frequency of feeding study Health, Wellbeing and Aging (HWA). Data were presented as means and standard deviations, absolute and relative frequencies. To analyze the frequency of consumption, there was a factor analysis with extraction of factors from the principal components analysis with varimax rotation. A bivariate analysis was performed using the chi-square and the magnitude of the effect observed by prevalence ratio (95% CI). The Poisson regression assessed the net effect of independent variables on the two outcomes, considering a significance level of 5%. We studied twelve Homes for the Aged totaling 381 seniors eligible for the study. The prevalence of risk of malnutrition was 46.1% (45.9 to 46.2) and malnutrition was 31.4% (31.2 to 31.5). The risk of malnutrition was significantly associated with the presence of urinary incontinence (RP = 1.444, 1.113 to 1.874) was associated with malnutrition and lack of appetite (RP = 1.757, 1.246 to 2.476), the fact that the individuals do not have access to food outside the institution (RP = 0.565, 0.337 to 0.946), low water consumption (RP = 1.646, 1.101 to 2.459) and dementia (PR = 1.537, 1.072 to 2.204). The high prevalence of malnutrition and risk of malnutrition in the study suggests that we should pay attention to information related to eating habits and the presence of comorbidities, as these can influence the nutritional status of this population

Uma ferramenta de análise automatizada de técnicas de seleção de testes de regressão baseada em mineração de repositórios de software

The main goal of Regression Test (RT) is to reuse the test suite of the latest version of a software in its current version, in order to maximize the value of the tests already developed and ensure that old features continue working after the new changes. Even with reuse, it is common that not all tests need to be executed again. Because of that, it is encouraged to use Regression Tests Selection (RTS) techniques, which aims to select from all tests, only those that reveal faults, this reduces costs and makes this an interesting practice for the testing teams. Several recent research works evaluate the quality of the selections performed by RTS techniques, identifying which one presents the best results, measured by metrics such as inclusion and precision. The RTS techniques should seek in the System Under Test (SUT) for tests that reveal faults. However, because this is a problem without a viable solution, they alternatively seek for tests that reveal changes, where faults may occur. Nevertheless, these changes may modify the execution flow of the algorithm itself, leading some tests no longer exercise the same stretch. In this context, this dissertation investigates whether changes performed in a SUT would affect the quality of the selection of tests performed by an RTS, if so, which features the changes present which cause errors, leading the RTS to include or exclude tests wrongly. For this purpose, a tool was developed using the Java language to automate the measurement of inclusion and precision averages achieved by a regression test selection technique for a particular feature of change. In order to validate this tool, an empirical study was conducted to evaluate the RTS technique Pythia, based on textual differencing, on a large web information system, analyzing the feature of types of tasks performed to evolve the SUT

Gestão Sustentável da água: um estudo da conscientização ambiental em atividades residenciais urbanas

The search for sustainable solutions through an appropriate environmental administration of the available natural resources, that comes from encounter to the aspirations of preservation of the environment and of the human being, in way to diagnose and to solve the environmental and social problems with the smallest possible impact to the nature and the man, it is the great challenge, so much for that generation, as for the future generations. The study of the environmental problems of the water and the participation and the social actors' environmental understanding as a whole, interferes in the field of the thematic environmental international, contemplating the strategic need of an appropriate administration of that very natural one, through a program returned to the diagnosis of the problems and in the search of compatible maintainable solutions, in a social and environmental politics of planning and environmental education, centered above all in the citizen's voice , user of that system. The present thesis she seeks to study the problem of the maintainable administration of the water, focusing the participation and the citizen's environmental understanding in the use of that very natural one for urban residential activities, in what concerns the approach and analyses of variables that treat of the measurement of general knowledge and you adapt, sense of community of the access to the means of information and of the attitudes and environmental behaviors, besides the variables of partner-demographic characterization or personal identification of the interviewed ones of an exploratory research of the type " survey ", accomplished through a stratified aleatory sampling, being the strata each one of the 4 (four) Political-Administrative Areas of the Natal city, having happened the collection of the data in the period of february to april/2002. The methodology used in this work it constitutes in the application of questionnaires with scales of the type Likert to measure the echo-varied of the study, besides a partner-demographic scale for the characterization of the studied sample. For the analysis of the results, it was made an exploratory descriptive study initially, followed by the use of techniques statistical multivariate s, such as, factorial analysis through the application of main components, besides the accomplishment of studies of multiple lineal regression. To complement this study, the accomplishment of Tests of Independence was proceeded through the Qui-square of Pearson, in way to verify the dependence of the associations between the partner-demographic variables and the principal selected variables and presents in the resulting factors of the factorial analysis. The results appear for a low level of environmental knowledge, of access to the information and community's sense, besides the verification that the principal factors resultants send for the need of feeling emphasis in the programs and administration actions addressed for the environmental understanding, the behaviors and attitudes that approach the information and the environmental education, besides the reuse of the water

Estrutura e desempenho organizacional: uma análise na Universidade Federal do Rio Grande do Norte

This research analyses the components of the organizational structure of the UFRN (Rio Grande do Norte Federal University) and to what extent they affect organizational performance. The study, classified as exploratory and descriptive, was conducted in two phases. The first phase consists of a pilot test to refine the research instrument and to identify the latent components of the organizational structure, and the second to characterize these components and thereby establish relationships with organizational performance. In the first phase, the research was conducted in 20 UFRN organizational units with the participation of 84 employees between technical-administrative and teachers, after considering missing values and outliers, while the second phase occurred in two stages: one conducted with 279 valid cases, consisting of technical-administrative and teachers of 37 UFRN units, and another with 112 managers of the institution in the 49 units identified in this research. The instrument adopted in the first phase was composed of 36 indicators of organizational structure, with six extracted and adapted from the instrument developed by Medeiros (2003) and 30 prepared based on the literature review, from Mintzberg (2012), Hall (1984), Vasconcellos and Hemsley (1997) and Seiffert and Costa (2007) and 7 performance indicators adapted from Fleury and Mills (2006), Vieira and Vieira (2003) and Kaplan and Norton (1997) from the self-assessment instrument in use by the university. In this stage the data were analyzed using the techniques of factor analysis and reliability analysis by means of Cronbach’s alpha, aiming to extract the factors representing the components of the organizational structure. In step 1 of the second phase, the instrument, refined and reduced in the previous phase, with 24 variables of organizational structure and 6 for performance was used, while in step 2, a semi-structured interview guide with questions, organized into nine organizational structure elements, was adopted aiming to gather information to understand the relationship of structure to performance of the UFRN. The techniques used in the second phase, as a whole, were factor analysis and reliability analysis to characterize the components extracted in the previous phase and to validate the performance variables and correlation analysis, regression and content analysis to establish and understand the relationship between structure and performance. The results showed, in the two stages, six latent components of organizational structure in the context under study: training and internalization, communication, hierarchy, decentralization, formalization and departmentalization - with high levels of Cronbach's alpha indexes - which can thereby be characterized as components of UFRN structure. Six performance indicators were validated in this study, showing them as efficient and highly reliable. Finally, it was found that the formalization, communication, decentralization, training and internalization components positively affect UFRN performance, while departmentalization has an adverse affect and hierarchy did not show a significant relationship. The results achieved in this work are important in future studies to support the development of a model structure that represents the specifics of the university

O estrategista em perspectiva: um estudo sobre o processo de formação de estratégias no ramo varejista de construção civil de Natal e região metropolitana

The strategy research have been widespread for many years and, more recently, the process of formation of the strategies in the individual perspective has also gained attention in academia. Confirming this trend, the goal of this study is to discuss the process of formation of the strategies from an individual perspective based on the three dimensions of the strategic process (change, thinking and formation) proposed by De Wit and Meyer (2004). To this end, this exploratory-descriptive study used the factor analysis techniques, non-parametric correlation and linear regression to analyze data collected from the decision makers of the 93 retail in the industry of construction supplies in the Natal and metropolitan area. As a result, we have that the formation factors of the dimensions investigated were identified in the majority, thus confirming the existence of paradoxes in the strategic process, and that there is a relationship between logical thinking and deliberate formation with the hierarchical level of decision makers.

Fatores que influenciam a predisposição dos usuários em aderir a uma política de segurança da informação

The information constitutes one of the most valuable strategic assets for the organization. However, the organizational environment in which it is inserted is very complex and heterogeneous, making emerging issues relevant to the Governance of information technology (IT) and Information Security. Academic Studies and market surveys indicate that the origin of most accidents with the information assets is the behavior of people organization itself rather than external attacks. Taking as a basis the promotion of a culture of safety among users and ensuring the protection of information in their properties of confidentiality, integrity and availability, organizations must establish its Information Security Policy (PSI). This policy is to formalise the guidelines in relation to the security of corporate information resources, in order to avoid that the asset vulnerabilities are exploited by threats and can bring negative consequences to the business. But, for the PSI being effective, it is required that the user have readiness to accept and follow the procedures and safety standards. In the light of this context, the present study aims to investigate what are the motivators extrinsic and intrinsic that affect the willingness of the user to be in accordance with the organization's security policies. The theoretical framework addresses issues related to IT Governance, Information Security, Theory of deterrence, Motivation and Behavior Pro-social. It was created a theoretical model based on the studies of Herath and Rao (2009) and D'Arcy, Hovav and Galletta (2009) that are based on General Deterrence Theory and propose the following influencing factors in compliance with the Policy: Severity of Punishment, Certainty of Detection, Peer Behaviour, Normative Beliefs, Perceived Effectiveness and Moral Commitment. The research used a quantitative approach, descriptive. The data were collected through a questionnaire with 18 variables with a Likert scale of five points representing the influencing factors proposed by the theory. The sample was composed of 391 students entering the courses from the Center for Applied Social Sciences of the Universidade Federal do Rio Grande do Norte. For the data analysis, were adopted the techniques of Exploratory Factor Analysis, Analysis of Cluster hierarchical and nonhierarchical, Logistic Regression and Multiple Linear Regression. As main results, it is noteworthy that the factor severity of punishment is what contributes the most to the theoretical model and also influences the division of the sample between users more predisposed and less prone. As practical implication, the research model applied allows organizations to provide users less prone and, with them, to carry out actions of awareness and training directed and write Security Policies more effective.

Mortalidade em idosos longevos e "mais jovens" no Brasil

The aim of the present study was to trace the mortality profile of the elderly in Brazil using two neighboring age groups: 60 to 69 years (young-old) and 80 years or more (oldest-old). To do this, we sought to characterize the trend and distinctions of different mortality profiles, as well as the quality of the data and associations with socioeconomic and sanitary conditions in the micro-regions of Brazil. Data was collected from the Mortality Information System (SIM) and the Brazilian Institute of Geography and Statistics (IBGE). Based on these data, the coefficients of mortality were calculated for the chapters of the International Disease Classification (ICD-10). A polynomial regression model was used to ascertain the trend of the main chapters. Non-hierarchical cluster analysis (K-Means) was used to obtain the profiles for different Brazilian micro-regions. Factorial analysis of the contextual variables was used to obtain the socio-economic and sanitary deprivation indices (IPSS). The trend of the CMId and of the ratio of its values in the two age groups confirmed a decrease in most of the indicators, particularly for badly-defined causes among the oldest-old. Among the young-old, the following profiles emerged: the Development Profile; the Modernity Profile; the Epidemiological Paradox Profile and the Ignorance Profile. Among the oldest-old, the latter three profiles were confirmed, in addition to the Low Mortality Rates Profile. When comparing the mean IPSS values in global terms, all of the groups were different in both of the age groups. The Ignorance Profile was compared with the other profiles using orthogonal contrasts. This profile differed from all of the others in isolation and in clusters. However, the mean IPSS was similar for the Low Mortality Rates Profile among the oldest-old. Furthermore, associations were found between the data quality indicators, the CMId for badly-defined causes, the general coefficient of mortality for each age group (CGMId) and the IPSS of the micro-regions. The worst rates were recorded in areas with the greatest socioeconomic and sanitary deprivation. The findings of the present study show that, despite the decrease in the mortality coefficients, there are notable differences in the profiles related to contextual conditions, including regional differences in data quality. These differences increase the vulnerability of the age groups studied and the health iniquities that are already present.

Imagens do terceiro setor: um estudo com pais e responsáveis financeiros das organizações educacionais

The present report is the result of an applied research in the educational entities of the third sector, aiming to demonstrate whether the financial influences the perception of users on the image of those entities. For both used the prospect of integrative marketing relationship adapting to and developing a set of indicators which bore the measurement of images from the model of Machado et al (2005) and Kotler and Fox (1994). The sample included a total of 187 parents and financial responsibility in 03 (three) institutions of education in Natal / RN. These data were processed by multivariate statistical analysis, factor analysis, linear regression, analysis of cluster and discriminant analysis. The factor analysis also identified 6 images perceived by users of services. Next were the relationships of cause and effect between the financial and images formed. In discriminant analysis, was identified two distinct groups of parents and guardians with financial perceptions similar and well defined. The result of the work shows that the differential level of financial participation of parents and guardians not influence the formation of the images formed from educational institutions of the third sector

Qualidade de vida no trabalho: o caso de enfermeiros dos Hospitais Públicos Walfredo Gurgel e Santa Catarina

The theoretical foundation of this study addresses the construct Quality of Worklife involving pro-active reading organizations in face to social developments of the working class, which is a challenge to the people s management. In this sense, as a contribution to the studies of quality of worklife (QOWL), this study addresses the quality of lifework of nurses at Walfredo Gurgel and Santa Catarina public hospitals. The goal is to make a diagnosis about the quality of lifework of these employees taking as a basis dimensions and performance indicators shown in the model by Fernandes (1996). The research is characterized by field, in a descriptive way. This survey comprised 75 nurses, with 49 by Walfredo Gurgel hospital and 26 by Santa Catarina one. The data collection was carried out through structured questionnaire. The questions were processed in the software Statistic 6.0, with factor analysis and multiple regressions, after the systematization of data. As a result, the most nurses in hospitals are dissatisfied with the quality of lifework, with the highest incidence in Santa Catarina hospital. The variable occupational health assessment was more negative in the hospital Santa Catarina one, whereas in Walfredo Gurgel, was family assistance. The variable guarantee of employment was more positive assessment in two hospitals without, though, implying in high importance on QOWL of nurses. The factor structure and decision showed greater sensitivity to explain the QOWL of nurses, joining 17 variables from 40 of the model. The factor working conditions, joining 6 variables, showed the second highest sensitivity. The compensation factor, gathering 5 variables, showed the third highest sensitivity while image and health factors showed minor importance