728 resultados para Base Norte - Ubatuba


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The nature of this thesis is interventionist and aims to create an alternative on how to control and evaluate the public policies implementation developed at the Institute for Technical Assistance and Rural Extension of Rio Grande do Norte State. The cenarium takes place in a public institution , classified as a municipality that belongs to the Rio Grande do Norte government and adopts the design science research methodology , where it generates a set of artifacts that guide the development of a computerized information system . To ensure the decisions, the literature was reviewed aiming to bring and highlight concepts that will be used as base to build the intervention. The use of an effective methodology called Iconix systems analysis , provides a software development process in a short time . As a result of many artifacts created by the methodology there is a software computer able of running on the Internet environment with G2C behavior, it is suggested as a management tool for monitoring artifacts generated by the various methods. Moreover, it reveals barriers faced in the public companies environment such as lack of infrastructure , the strength of the workforce and the executives behavior

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This study s main goal is to analyze the way the limits between Ceará and Rio Grande do Norte states, the so called Grossos matter, has been associated to the norte-rio-grandense spacial and identity formation during the first republic period. Thus, a consistet number of sources: RN and CE old newspapers, as well as a república from Natal and Fortaleza and o mossoroense ; historical drafts from the historical and geographical institute associated and historical, gographical and anthropological institute of Ceará; the Ação Cível Originária de nº 6 from the supreme federal tribunal and many other cartographies. The documents haven t been hierarchized, neither accepted as proof effects, but understood as the base matter for this text composition by the deconstruction of the analyzed discusses. In order to do that the ablação or bricolagem method, without quotations marks or long quotations themselves, has been used. Along the three analyzed charpters: the two phases the litigious was found, since its beginning yet in the XVIII century until 1888 and its return within the republic proclamation, in the 1920 resolution; the development of the documental, historical and identity dispute between IHGA-CE and IHG-RN; and, at last, the political game existing between the Albuquerque Maranhão oligarchy , Manuel Pereira Reis and Rui Barbosa, explaining the intentions, silent and miths built along the time by these intellectual participations

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Currently one of the major concerns in sports is to identify, select, discover and reveal talents in soccer. As principal reasons is perceived the search direct or indirect for resources for players, clubs, media, sports brands and their sponsors. However, high salaries are an exception and not a rule, because the majority of professional players in Brazil receives 1 minimum salary per month. It is also known that on professional clubs, daily, arriving several players to try to be a professional soccer player, however, the majority of clubs - almost all does not present methodological, systematic and analytical aspects to select promising players. The selective processes ("sieves" or "big sieves") developed by technical observers ( olheiros") summarized in the observation of the sportive performance of a big group of players in a period of few minutes given to each player. In this period the target behavior is the ability with the ball. If promising players are identified on that selection, they are referred to the club for a new observation, which will be conducted by the responsible coach of base category in question. It is understood by base categories, the amateur categories (not professional), to serve as a "base" for the formation of the cast of professional clubs. What are sub-13 (under 13 years), sub-15 (under 15 years), sub-17 (under 17 years) and sub-20 (under 20 years). The absence of common criterias and performance indicators of these professionals may hamper the evaluation of promising players, and be a costly activity for the club. This study proposes to identify, characterize and categorize the criterias and methods of behavioral evaluation, used by coaches of base categories of Rio Grande do Norte (RN) to evaluate the sportive performance of young soccer players, with the purpose of to compare the criterias of evaluation of sportive performance of young soccer players, used by coaches with different time of experience in function. The proposal had 2 pilot studies, the first (June and July, 2007) were interviewed 29 coaches, 17 of category sub-13 and 12 of category sub-17. The data were tabulated and organized into spreadsheets in order to describe, and developed a set of descriptors of behavior. And the second (May and June, 2008), with revisions made based on observations, analysis and descriptions found in the first, were interviewed 14 technical of category sub-15. After the results found in pilots, it was possible to outline the study in question, which had 46 coaches base categories of the RN. And from the results show that the characteristic of greatest importance, according to the interviewees was the behavior, the 2nd most important characteristic considered was the motivation, the 3rd was the ability and the 4th was the physical condition and the last was the affiliation. And by analyzing the results to the methods of evaluation of sportive performance used by coaches, it was noted clearly that most uses only the observation to select young soccer players. Therefore, needs a systematization to the selection of soccer players, since there is complexity in the verification of characteristics and aspects involved with purpose to avoid wrong evaluations and selections and the results negligible

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The importance of identifying the consequence of the hours worked on people in society has been well recognized within Organizational and Work Psychology. From this point of view, the present research had the objective of analysing the effects of work regimes on the mental health of petroleum operators of Petrobrás. The sample totaled 144 subjects, corresponding to 27% of the work population. The mental health of the participants was evaluated using the following instruments of measurement: QSG-12, Scale of self-esteem, Scale of Positive and Negative Affections and the Scale of Valuable Attributes of IMST, each representing an empirical factor used to indicate and measure the five dimensions of mental health. The subjects perceptions of their work regime and the rest of their conditions of work were evaluated using scales of descriptive attributes of IMST, by applying a semi-structured questionnaire and by use of interviews. A socio-demographic file was used to collect information related to the biographical and socio-occupational profile of the worker sample. The answers to the questionnaire were inserted into the data bank of SPSS (Statistical Package for Social Science), for statistical analysis, and the interviews were analised based on the technique of Contents Analysis recommended by Bardin (1995). The main results revealed that one third of the worker sample were tense; however, the mental health of the majority was preserved. Cluster Analysis applied to the group of seven factors which measured the five dimensions of mental health identified four profiles of psychological well-being shared between members of the sample. It was observed that the people working in the system of Continuous Shift Alternation (TIR) and in the system of Pre-advising tended to present balanced and satisfactory profiles, while the ones which worked in the Administrative Field tended to present anxious and oscillating profiles, and thus were more affected psychologically. These were also the ones that also perceived the more negative aspects of their laborious conditions (reduced chances of self-improvement, physically stressful and financial resources below expectations with which to supply family and personal necessities. In agreement with the ecological model formulated by Warr (1987), the present study concluded that the positive and negative effects on the psychological well-being tended to occur as a consequence of the perceptions the petrol operators developed to face their work conditions

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In this work, the objective in study was the development of a biossensor potencyometric for urea detection, starting from the extracted urease of soy grains. Initially, was made a chemometrics study, through a planning factorial 24, objectified to find great conditions for the extraction of the urease without its properties were affected. Starting from this study, the best conditions were determined for the obtaining of rich extracts in urease, allowing the biossensors making with good characteristics. These were made using a platinum electrode as transducer with the dispersed urease in chitosan head office and reticulated in glutaraldehyde vapor. The biossensors obtained presented a limit of urea detection the same to 0,33 mM and lineal strip between 0,33 and 3 mM of the substratum. The time of answer was considered loud, mainly, in low concentrations of the substratum, where it was taken about 5 minutes by analysis. For high concentrations that time was reduced for not more than one minute. The time of life was limited by the adherence of the enzymatic membrane to the transducer, but it was possible to maintain the biossensor with operation for one month with about 50 accomplished measures. Application of the biossensor for analyses of fertilizers to the urea base presented excellent result for a sample with few interfering, but it was different when the used fertilizer was originating from of a complex sample. Even so the label was not expressed the text of nitrogen it was totally coming of the urea. An evaluation of the kinetic parameters of the catalytic reaction of the biossensor showed coherence with the results exposed in the literature

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The aim of this work was the preparation of polyols from reactions between castor oil and dietanolamine to increase the hydroxyl content and the network degree in the products to application in electronic devices. The polyols and the mixtures obtained were characterized by nuclear magnetic ressonance. Castor oil (CO) is a natural triglyceride - based polyol possessing hydroxyl groups, which allow several reactions that produce many different products. Among them are the polyurethanes (PU), which have been considered an ideal product for the covering of electricelectronic circuits, due to their excellent electrical, shock-absorbing, solvents resistance and hydrolytic stability properties. About 90% of the fatty acids present in the castor oil are ricinoleic acid (12-hydroxyoleic acid), while the remaining 10% correspond to non-hydroxylated fatty acids, mainly linoleic and oleic acids. The chemical analysis of castor oil indicates a hydroxyl number of 2.7. In this work, a polyol was obtained by the reaction of the CO with diethanolamine (DEA), in order to elevate the hydroxyl value from 160 to 230 or to 280 mgKOH/g, and characterized by nuclear magnetic resonance (NMR) 1H and 13C (Mercury 200). The polyadition of the resulting polyol with isophorone diisocianate (IPDI) was carried out at 60°C, and the reaction kinetics was followed by rheological measurements in a Haake RS150 rheometer. The electrical properties were determined in a HP LCR Meter 4262A, at 1.0 Hz and 10.0 KHz. The chemical analysis showed that the polyols obtained presented hydroxyl number from 230 to 280 mgKOH/g. The polyadition reaction with IPDI produced polyurethane resins with the following properties: hardness in the range from 45 shore A to 65 shore D (ASTM D2240); a dielectric constant of 3.0, at 25°C (ASTM D150). Those results indicate that the obtained resins present compatible properties to the similar products of fossil origin, which are used nowadays for covering electric-electronic circuits. Therefore, the PUs from castor oil can be considered as alternative materials of renewable source, free from the highly harmful petroleum - derived solvents

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Were synthesized different ferrites NixZn1-xFe2O4 (0,4 ≤ x ≤ 0,6) compositions by using citrate precursor method. Initially, the precursors citrates of iron, nickel and zinc were mixed and homogenized. The stoichiometric compositions were calcined at 350°C without atmosphere control and the calcined powders were pressed in pellets and toroids. The pressed material was sintered from 1100º up to 1200ºC in argon atmosphere. The calcined powders were characterized by XRD, TGA/DTG, FTIR, SEM and vibrating sample magnetometer (VSM). All sintered samples were characterized using XRD, SEM, VSM and measurements of magnetic permeability and loss factor were obtained. It was formed pure ferromagnetic phase at all used temperatures. The Rietveld analyses allowed to calculate the cations level occupation and the crystallite size. The analyses obtained nanometric crystals (12-20 nm) to the calcined powder. By SEM, the sintered samples shows grains sizes from 1 to 10 μm. Sintered densities (ρ) were measured by the Archimedes method and with increasing Zn content, the bulk density decrease. The better magnetization results (105-110 emu/g) were obtained for x=0,6 at all sintering temperatures. The hysteresis shows characteristics of soft magnetic material. Two magnetization processes were considered, superparamagnetism at low temperature and the magnetic domains formation at high temperatures. The sintered toroids presents relative magnetic permeability (μr) from 7 to 32 and loss factor (tanδ) of about 1. The frequency response of toroids range from 0,3 kHz to 0,2 GHz. The composition x=0,5 presents both greater μr and tanδ values and x=0,6 the most broad range of frequency response. Various microstructural factors show influence on the behavior of μr and tanδ, such as: grain size, porosity across grain boundary and inside the grain, grain boundary content and domain walls movement during the process of magnetization at high frequency studies (0,3kKz 0,2 GHz)

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The present work aims the preparation of filmes of strontium-doped lanthanum manganite (perovskita) yttria-stabilized zirconia (LSM-SDC) films deposited on substrate of YSZ by means of spin coating technique having as principal objective their application to solid oxide fuel cells of intermediate temperature. La0,8Sr0,2MnO3 and Ce0,8Sm0,2O1,9 were obtained by modified Pechini method by use of gelatin which act as polymerization agent. The powders obtained were characterized by Xray fluorescence, X ray diffraction, electronic scanning microscopy and the superficial area by BET method. The results obtained by X-ray fluorescence showed that the route adopted for obtention of powders was effective in the obtention of the compositions with close values to the stoichiometrics. Ethyl cellulose was used as pore-forming agent and mixed with the LSM-SDC powders in weight proportions of 1:24, 2:23 and 1:9. The films were sintered at 1150 °C for 4 h and characterized by X-ray diffraction and scanning electron microscopy technique (SEM) and atomic force. The phases quantification of the precursory powders and of the obtained films was carried through Rietveld method. According with the analysis of SEM, as the content of ethyl cellulose was increased, the pore distribution in films become more uniform and the pore size reduced. The methodology used for the obtention of the films was very efficient, considering a material was obtained with characteristics that were proper to the application as electrolyte/cathode system to solid oxide fuel cells

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The oxidative desulfurization process (ODS) of a commercial diesel fuel was performed under mild conditions in the presence of catalysts based on vanadium or manganese, supported on alumina, clays (commercial, natural and pillared) and zeolites (NaX, NaY, beta, mordenite and ZSM-5). The catalysts were synthesized by wet impregnation and characterized by X-ray diffraction, textural analysis by N2 adsorption and scanning electron microscopy. The dibenzothiophene (DBT) was used as sulfur compound in catalytic evaluation. The reactions were performed using acetonitrile as solvent and the hydrogen peroxide as oxidant at 55°C. The reaction products were analized by gas chromatography (GC-FID). In the studied conditions, the process was efficient due to the DBT was converted to its corresponding sulfone. Both DBT and corresponding sulfone were extracted by the solvent. Removals and oxidations up to 100% of sulfur compound were achieved. The catalysts supported on ZSM-5 zeolite showed are more effective for oxidation reaction of sulfur compound, presenting the best results. It was observed for oxidation reaction, that vanadium catalysts were more effective and manganese catalysts showed best results for removal of sulfur compounds

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Nowadays, chemistry contents taught in high school continue to be presented in a fragmented and decontextualized manner by the teachers and the textbooks. Even though it is known that contextualization and interdisciplinary exchange play an important role in the process of Chemistry teaching/learning. Therefore, the present study aims at enlightening the importance of these methodological foundations in the learning of chemistry. The data acquisition about the subject Contextualization and Interdisciplinary Exchange involved in Chemistry Teaching was developed through bibliographical researches on chemistry textbooks, which focused on the analysis of the topics acid and base , since it is a theme studied throughout all three years of high school. The present study also developed questionnaires which were applied to analyze to what extent chemistry teachers are working in a contextualized and interdisciplinary manner throughout the process of Chemistry teaching/learning. The results obtained in the researches show that a contextualized and interdisciplinary teaching contributes to a more meaningful acquisition of chemistry knowledge, in a dynamic and interactive way, but there are still many roadblocks towards the achievement of this kind of Chemistry teaching/learning process

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Oxygen carriers are metal oxides which have the ability to oxidize and reduce easily by various cycles. Due to this property these materials are widely usedin Chemical-Looping Reforming processes to produce H2 and syngas. In this work supports based on MCM-41 and La-SiO2 were synthesized by hydrothermal method. After the synthesis step they were calcined at 550°C for 2 hours and characterized by TG, XRD, surface area using the BET method and FTIR spectroscopy. The deposition of active phase, in this case Nickel, took place in the proportions of 5, 10 and 20% by weight of metallic nickel, for use as oxygen carriers.The XRD showed that increasing in the content of Ni supported on MCM-41 resulted in a decrease in spatial structure and lattice parameter of the material. The adsorption and desorption curves of the MCM-41 samples exhibited variations with the increase of Ni deposited. Surface area, average pore diameter and wall density of silica showed significant changes , due to the increase of the active phase on the mesoporous material. By other hand, in the samples with La-SiO2 composition was not observed peaks characteristic of hexagonal structure, in the XRD diffractogram. The adsorption/desorption isotherms of nitrogen observed are type IV, characteristic of mesoporous materials. The catalytic test indicates that the supports have no influence in the process, but the nickel concentration is very important, because the results for minor concentration of nickel are not good. The ratio H2/O2 was close to 2, for all 15 cycles involving the test storage capacity of O2, indicating that the materials are effective for oxygen transport

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Sustainable development is a major challenge in the oil industry and has aroused growing interest in research to obtain materials from renewable sources. Carboxymethylcellulose (CMC) is a polysaccharide derived from cellulose and becomes attractive because it is water-soluble, renewable, biodegradable and inexpensive, as well as may be chemically modified to gain new properties. Among the derivatives of carboxymethylcellulose, systems have been developed to induce stimuli-responsive properties and extend the applicability of multiple-responsive materials. Although these new materials have been the subject of study, understanding of their physicochemical properties, such as viscosity, solubility and particle size as a function of pH and temperature, is still very limited. This study describes systems of physical blends and copolymers based on carboxymethylcellulose and poly (N-isopropylacrylamide) (PNIPAM), with different feed percentage compositions of the reaction (25CMC, 50CMC e 75CMC), in aqueous solution. The chemical structure of the polymers was investigated by infrared and CHN elementary analysis. The physical blends were analyzed by rheology and the copolymers by UV-visible spectroscopy, small-angle X-ray scattering (SAXS), dynamic light scattering (DLS) and zeta potential. CMC and copolymer were assessed as scale inhibitors of calcium carbonate (CaCO3) using dynamic tube blocking tests and chemical compatibility tests, as well as scanning electron microscopy (SEM). Thermothickening behavior was observed for the 50 % CMC_50 % PNIPAM and 25 % CMC_75 % PNIPAM physical blends in aqueous solution at concentrations of 6 and 2 g/L, respectively, depending on polymer concentration and composition. For the copolymers, the increase in temperature and amount of PNIPAM favored polymer-polymer interactions through hydrophobic groups, resulting in increased turbidity of polymer solutions. Particle size decreased with the rise in copolymer PNIPAM content as a function of pH (3-12), at 25 °C. Larger amounts of CMC result in a stronger effect of pH on particle size, indicating pH-responsive behavior. Thus, 25CMC was not affected by the change in pH, exhibiting similar behavior to PNIPAM. In addition, the presence of acidic or basic additives influenced particle size, which was smaller in the presence of the additives than in distilled water. The results of zeta potential also showed greater variation for polymers in distilled water than in the presence of acids and bases. The lower critical solution temperature (LCST) of PNIPAM determined by DLS corroborated the value obtained by UV-visible spectroscopy. SAXS data for PNIPAM and 50CMC indicated phase transition when the temperature increased from 32 to 34 °C. A reduction in or absence of electrostatic properties was observed as a function of increased PNIPAM in copolymer composition. Assessment of samples as scale inhibitors showed that CMC performed better than the copolymers. This was attributed to the higher charge density present in CMC. The SEM micrographs confirmed morphological changes in the CaCO3 crystals, demonstrating the scale inhibiting potential of these polymers

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Dispersions composed of polyelectrolyte complexes based on chitosan and poly(methacrylic acid), PMAA, were obtained by the dropping method and template polymerization. The effect of molecular weight of PMAA and ionic strength on the formation of chitosan/poly(methacrylic acid), CS/PMAA, complexes was evaluated using the dropping method. The increase in molecular weight of PMAA inhibited the formation of insoluble complexes, while the increase in ionic strength first favored the formation of the complex followed by inhibiting it at higher concentrations. The polyelectrolyte complexation was strongly dependent on macromolecular dimensions, both in terms of molecular weight and of coil expansion/contraction driven by polyelectrolyte effect. The resultant particles from dropping method and template polymerization were characterized as having regions with different charge densities: chitosan predominating in the core and poly(methacrylic acid) at the surface, the particles being negatively charged, as a consequence. Albumin was adsorbed on templatepolymerized CS/PMAA complexes (after crosslinking with glutardialdehyde) and pH was controlled in order to obtain two conditions: (i) adsorption of positively charged albumin, and (ii) adsorption of albumin at its isoelectric point. Adsorption isotherms and zeta potential measurements showed that albumin adsorption was controlled by hydrogen bonding/van der Waals interactions and that brushlike structures may enhance adsorption of albumin on these particles

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There is a lack of clinical studies evaluating techniques of functional impression for partially edentulous arches. The aim of this double-blind non-randomized controlled clinical trial was to compare the efficacy of altered cast impression (ACI) and direct functional impression (DFI) techniques. The efficacy was evaluated regarding the number of occlusal units on denture teeth, mucosa integrity at 24-hour follow-up and denture base extension. The sample included 51 patients (female and male) with mean age of 58.96 years treated at Dental Department of UFRN. The patients, exhibiting edentulous maxilla and mandibular Kennedy class I, were divided into two groups (group ACI, n=29; group DFI, n=22). Clinical evaluation was based on the number of occlusal units on natural and/or artificial teeth, mucosa integrity at 24-hour follow-up, and denture base extension. Statistical analysis was conducted using the software SPSS 17.0® (SPSS Inc., Chicago, Illinois). Student T-test was used to reveal association between number of occlusal units and impression technique while chi-square test showed association between mucosa integrity and impression technique. Fischer s exact test was applied for association between denture base extension and impression technique at 95% level of significance. No significant difference was observed between the groups regarding number of occlusal units, mucosa integrity and denture base extension. The altered cast technique did not provide significant improvement in comparison to the direct technique when the number of occlusal units, mucosa integrity and denture base extension

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Java Card technology allows the development and execution of small applications embedded in smart cards. A Java Card application is composed of an external card client and of an application in the card that implements the services available to the client by means of an Application Programming Interface (API). Usually, these applications manipulate and store important information, such as cash and confidential data of their owners. Thus, it is necessary to adopt rigor on developing a smart card application to improve its quality and trustworthiness. The use of formal methods on the development of these applications is a way to reach these quality requirements. The B method is one of the many formal methods for system specification. The development in B starts with the functional specification of the system, continues with the application of some optional refinements to the specification and, from the last level of refinement, it is possible to generate code for some programming language. The B formalism has a good tool support and its application to Java Card is adequate since the specification and development of APIs is one of the major applications of B. The BSmart method proposed here aims to promote the rigorous development of Java Card applications up to the generation of its code, based on the refinement of its formal specification described in the B notation. This development is supported by the BSmart tool, that is composed of some programs that automate each stage of the method; and by a library of B modules and Java Card classes that model primitive types, essential Java Card API classes and reusable data structures