Membrana de alumina anódica: comportamento da microestrutura e estudo das propriedades ópticas após tratamento térmico

Thin commercial aluminum electrolytic and passed through reactions was obtained with anodic alumina membranes nanopores. These materials have applications in areas recognized electronic, biomedical, chemical and biological weapons, especially in obtaining nanostructures using these membranes as a substrate or template for processing nanowires, nanodots and nanofibers for applications noble. Previous studies showed that the membranes that have undergone heat treatment temperature to 1300° C underwent changes in morphology, crystal structure and optical properties. This aim, this thesis, a study of the heat treatment of porous anodic alumina membranes, in order to obtain and to characterize the behavior changes structures during the crystallization process of the membranes, at temperatures ranging between 300 and 1700° C. It was therefore necessary to mount a system formed by a tubular furnace resistive alumina tube and controlled environment, applying flux with special blend of Ag-87% and 13% N2, in which argon had the role of carrying out the oxygen nitrogen system and induce the closing of the pores during the densification of the membrane. The duration of heat treatment ranged from 60 to 15 minutes, at temperatures from 300 to 1700° C respectively. With the heat treatment occurred: a drastic reduction of porosity, grain growth and increased translucency of the membrane. For the characterization of the membranes were analyzed properties: Physical - thermogravimetric, X-ray diffraction, BET surface area; morphological - SEM, EDS through compositional and, optical absorbance, and transmittance in the UV-VIS, and FTIR. The results using the SEM showed that crystallization has occurred, densification and significant changes in membrane structure, as well as obtaining microtube, the BET analysis showed a decrease in specific surface area of the membranes has to 44.381 m2.g-1 to less than 1.8 m2.g-1 and in the analysis of transmittance and absorbance was found a value of 16.5% in the range of 800 nm, characteristic of the near infrared and FTIR have confirmed the molecular groups of the material. Thus, one can say that the membranes were mixed characteristics and properties which qualify for use in gas filtration system, as well as applications in the range of optical wavelength of the infra-red, and as a substrate of nanomaterials. This requires the continuation and deepening of additional study

Construção de um aparato experimental para monitoramento in situ da deposição de filmes finos de titânio por magnetron sputtering

The technique of surface coating using magnetron sputtering is one of the most widely used in the surface engineering, for its versatility in obtaining different films as well as in the micro / nanometric thickness control. Among the various process parameters, those related to the active species of the plasma are of the most fundamental importance in the mechanism and kinetics of deposition. In order to identify the active species of the plasma, parameters such as gas flow, pressure and density of electric power were varied during titanium coating on glass substrate. By flowing argon gas of 10, 20, 30, 40 and 50 sccm (cubic centimeters per minute) for each gas flow a sequential scan of the electric current of 0.10, 0.20, 0.30, 0.40 , 0.50 A. The maximum value of 0.50 A was chosen based both on literature data and on limitations of the equipment. The monitoring of plasma species present during the deposition was carried out in situ by the technique of optical emission spectroscopy (OES) through the spectrometer Ocean Optics USB2000 Series. For this purpose, an apparatus was developed to adapt the OES inside the plasma reactor to stay positioned closest to the target. The radiations emitted by the species were detected by an optical fiber placed behind the glass substrate and their intensities as a function of wavelength were, displayed on a monitor screen. The acquisition time for each condition of the plain parameters was related to the minima of spectral lines intensities due to the film formed on the substrate. The intensities of different emission lines of argon and titanium were then analyzed as a function of time, to determine the active species and estimate the thickness of the deposited films. After the deposition, the coated glasses thin films were characterized by optical transmittance through an infrared laser. It was found that the thickness and deposition rate determined by in situ analysis were consistent with the results obtained by laser transmittance

Efeito de argilas organofílicas na estrutura e propriedades de nanocompósitos de poli(metacrilato de metila)

Nacomposites of polymers and lamellar clayminerals, has generated high scientific and technological interest, for having mechanical properties and gas barriers differentiated of polymers and conventional composites. In this work, it was developed nanocomposites by single screw extruder and injection, utilizing commercial raw material, with the goal to investigate the quality of new developed materials. It was evaluated the influence of the content and the kind of clay in the structure and in the nanocomposites properties. It was used regular and elastomeric poly (methyl methacrylate) (Acrigel LEP 100 and Acrigel ECP800) and six montmorillonites (Cloisite 10A, 11B, 15A, 20A, 25A e 30B) at the concentration of 1% e 3% in weight. The nanocomposites were characterized by X-ray diffraction (XRD), thermal gravimetric analysis (TGA), transmission electron microscopy (TEM), colorimetric, optical transparency, flexural and tensile tests, Rockwell hardness and esclerometry. It was founded that is possible to obtain intercalated and exfoliated nanocomposites PMMA/MMT, and the top results was obtained in the materials with 1%in clay weight organophilizated with 2M2HT (Cloisite 15A and 20A) presented intercalate and hybrid morphology (exfoliated and flocullated). The ones that was produced with organophilizated clay with 2MHTL8 (Cloisite 30B) had excellent visual quality, but the majority presented hybrid morphology. In the materials processed with organophilizated clay with MT2ETOH (Cloisite 30B), there were color change and loss of transparency. It occurs improvement in a few mechanical properties, mainly in the materials produced with PMMA elastomeric (Acrigel ECP800), being more significant, the increase in the resistance to stripping in those nanocomposites

Determinação do perfil térmico em amostras de aço AISI M35 imersas em plasma

The heat transfer between plasma and a solid occurs mostly due the radiation and the collision of the particles on the material surface, heating the material from the surface to the bulk. The thermal gradient inside the sample depends of the rate of particles collisions and thermal conductivity of the solid. In order to study that effect, samples of AISI M35 steel, with 9,5 mm X 3,0 mm (diameter X thickness) were quenched in resistive furnace and tempereds in plasma using the plane configuration and hollow cathode, working with pressures of 4 and 10 mbar respectively. Analyzing the samples microstructure and measuring the hardness along the transversal profile, it was possible to associate the tempered temperature evaluating indirectly the thermal profile. This relation was obtained by microstructural analyzes and through the hardness curve x tempered sample temperature in resistive furnace, using temperatures of 500, 550, 600, 650 and 700°C. The microstructural characterization of the samples was obtained by the scanning electron microscopy, optic microscopy and X-ray diffraction. It was verified that all samples treated in plasma presented a superficial layer, denominated affected shelling zone, wich was not present in the samples treated in resistive furnace. Moreover, the samples that presented larger thermal gradient were treated in hollow cathode with pressure of 4 mbar

Redução aluminotérmica do óxido de tântalo usando uma tocha de plasma como ignitor

In this work was used a plasma torch of non transferred arc with argon as work gas, using a power supply with maximum DC current of 250 A and voltage of 30 V to activate the plasma and keep it switched on. The flame temperature was characterized by optical emission spectroscopy, through Boltzmann-plot-method. The torch has been used like igniter in the aluminothermic reduction of the mixture tantalum oxide and aluminum, seeking to obtain metallic tantalum. In heating of the reagents only one particle will be considered to study interactions between plasma-particle, seeking to determinate its fusion and residence time. The early powders were characterized by laser granulometry, scanning electron microscopy (SEM) and X-ray diffraction analysis. The final product of this reaction was characterized by SEM and X-ray diffraction. Crystallite size was calculated by the Scherrer equation and microdeformation was determined using Willamsom-Hall graph. With Rietveld method was possible to quantify the percentile in weight of the products obtained in the aluminothermic reaction. Semi-quantitative chemical analysis (EDS) confirmed the presence of metallic tantalum and Al2O3 as products of the reduction. As was waited the particle size of the metallic tantalum produced, presents values in nanometric scale due the short cooling time of those particles during the process

Avaliação da correlação entre os parâmetros, carbono orgânico total e elementos tóxicos, em solo de um posto de serviço e revenda de combustíveis

Today a major responsibility for the contamination of soil and groundwater and surface water are establishments known as gas stations of fuel which has attracted increasing attention from both the general population as the state agencies of environmental control due to leaks in storage tanks and mainly to disruption of pipe corrosion of tanks and pumping. Other services, like oil changes and car wash are also causes for concern in this type of establishment. These leaks can cause or waste produced, and the contamination of aquifers, serious health problems and public safety, since most of these stations located in urban areas. Based on this, the work was to evaluate soil contamination of a particular service station and fuel sales in the city of Natal, through the quantification of heavy metals like Cd, Cu, Cr, Ni, Pb, Zn of total organic carbon (TOC) and organic matter using different techniques such as optical emission spectrometry with inductively coupled plasma source (ICP OES), Total Organic Carbon analyzer and gravimetric analysis respectively. And also to characterize the soil through particle size analysis. Samples were taken in 21 georeferenced points and collected in the same period. The soils sampled in sampling stations P3, P5, P6, P10, P11, P12, P13, P14, P15, P17, P18 and P20 showed the smallest size fractions ranging from fine sand to medium sand. The other study sites ranged from fine sand to medium sand, except the point P8 showed that only the type size medium sand and P19, indicating a particle size of the coarse type. The small correlation of organic matter with the elements studied in this work suggests that these are not of anthropogenic origin but geochemical support

Avaliação do efeito de um adoçante comercial com sucralose na marcação de constituintes sanguíneos com tecnécio-99m, na morfologia das hemácias e na biodisponibilidade dos radiofármacos pertecnetato de sódio e ácido dietilenotriaminopentacético-tecnécio-99m em ratos Wistar.

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Avaliação da atividade biológica de óleos essenciais sobre candida não albicans de origem clínica

Candidíase é um problema de importância crescente, devido o aumento do número de indivíduos imunocomprometidos e o surgimento de cepas resistentes aos antifúngicos convencionais. É de fundamental importância a busca por novos agentes antifúngicos mais eficazes, menos tóxicos, sendo os óleos essenciais (OEs) excelentes alternativas para esse propósito. Esse estudo investigou a atividade biológica do OE de Mentha spicata L. sobre Candida guilliermondii de origem anal e vaginal. Para tanto foram determinadas a Concentração Inibitória Mínima (CIM), Concentração Fungicida Mínima (CFM), cinética do crescimento das leveduras (Time-Kill), alterações micromorfológicas (técnica do microcultivo em câmara úmida) e investigação do mecanismo de ação antifúngico, utilizando o bioensaio do sorbitol. O OE de M. spicata foi obtido pelo processo de extração por destilação a vapor. Na análise fitoquímica desse óleo foi observada a presença de carvona com 84,32%, seguida pelo limoneno (13,70%) e traços de iso-dihidrocarvona (0,82%). Os resultados da análise da CIM variou entre 32 e 128 μg/mL. A CFM variou entre 64 e 1024 μg/mL. Na avaliação da ação de OE e da nistatina 100UI/mL, o antifúngico padrão apresentou o efeito fungicida a partir de 4 horas e para OE de M. spicata foi observado efeito fungistático na CIM, CIMX2 e CIMX4 frente às cepas avaliadas. O OE de M. spicata apresentou forte atividade antifúngica contra as cepas de C. guilliermondii, promovendo alterações micromorfológicas visíveis por microscopia óptica, nas concentrações testadas (CIM, CIMx2), resultado semelhante ao que se observou com a nistatina (100UI/mL). Na investigação do mecanismo de ação antifúngico foi constatado que houve alteração da CIM na presença de sorbitol, com elevação dos valores quatro vezes maior que a concentração inicial, o que indica que os componentes desse OE apresentam ação direta sobre a parede celular das leveduras. Conclui-se que o OE de Mentha spicata é um potencial agente terapêutico no tratamento de candidíase

Fisioterapia e sociedade: ações do Sistema Único de Saúde no Rio Grande do Norte

The work has objective to present actions of Physiotherapy, developed by SUS in the State of Rio Grande do Norte; discuss under the humanization point of view such actions of health; discuss the importance of physioterapy to the Norte-Riograndense, or maybe its role in the perpetuation of actions of health centered in the binomial cause/efect. The study was done in the State of Rio Grande do Norte. The data were obtained through public sources gathered in the health secretrary ship of this State. The collected data talks about physiotherapy sections developed by SUS in several areas of the State; such data was collected and analysed after the aproval of Ethic and Resarch Committee of Federal University of Rio Grande do Norte. Concerning the physiotherapy, along with the State Health Secretaryship of the State fo Rio Grande do Norte, there were only records of attending based on cure/rehabillitation, not being observed during the curse of study, any record or action of prevention, promotion and protection towards health. It s possible to notice that there is a highligth to the interventions focusing on the treatment of illness of rheumatic origin and general complaints related to the vertebral column. Such research evidenced that the Physiotherapy in the SUS in the State priorizes the individualized attending centered in the carteziano health/illness model, where the developde actions are turned to the curative and rehabilliting attention, with role fo some or no highligth in the primary attention

Estudo de pré-formulação para dose fixa combinada dos tuberculostáticos rifampicina, isoniazida, pirazinamida e etambutol (4 em 1)

According to the global framework regarding new cases of tuberculosis, Brazil appears at the 18th place. Thus, the Ministry of Health has defined this disease as a priority in the governmental policies. As a consequence, studies concerning treatment and prevention have increased. Fixed-dose combination formulations (FDC) are recognized as beneficial and are recommended by WHO, but they present instability and loss on rifampicin bioavailability. The main purpose of this work was to carry out a pre-formulation study with the schedule 1 tuberculosis treatment drugs: rifampicin, isoniazid, pyrazinamide and ethambutol and pharmaceutical excipients (lactose, cellulose, magnesium stearate and talc), in order to develop an FDC product (150 mg of rifampicin + 75 mg of isoniazid + 400 mg of pyrazinamide + 250 mg of ethambutol). The studies consisted of the determination of particle size and distribution (Ferret s diameter) and shape through optical microscopy, as well as rheological and technological properties (bulk and tapped densities, Hausner Factor, Carr s Index, repose angle and flux rate) and interactions among drugs and drug excipient through thermal analysis (DSC, DTA, TG and your derivate). The results showed that, except isoniazid, the other drugs presented poor rheological properties, determined by the physical characteristics of the particles: small size and rod like particles shape for rifampicin; rectangular shape for pyrazinamide and ethambutol, beyond its low density. The 4 drug mixture also not presented flowability, particularly that one containing drug quantity indicated for the formulation of FDC products. In this mixture, isoniazid, that has the best flowability, was added in a lower concentration. The addition of microcrystalline cellulose, magnesium stearate and talc to the drug mixtures improved flowability properties. In DSC analysis probable interactions among drugs were found, supporting the hypothesis of ethambutol and pyrazinamide catalysis of the rifampicin-isoniazid reaction resulting in 3- formylrifamycin isonicotinyl hydrazone (HYD) as a degradation product. In the mixtures containing lactose Supertab® DSC curves evidenced incompatibility among drugs and excipient. In the DSC curves of mixtures containing cellulose MC101®, magnesium stearate and talc, no alterations were observed comparing to the drug profiles. The TG/DTG of the binary and ternary mixtures curves showed different thermogravimetrics profiles relating that observed to the drug isolated, with the thermal decomposition early supporting the evidences of incompatibilities showed in the DSC and DTA curves

Formação de educadores de jovens e adultos no Programa Geração Cidadã: relação entre saberes na proposição curricular

This paper deals with the fundamental elements of a curricular proposal aiming at the formation of alphabetizers of young and adults, as long as it concerns the relation between the academic knowledge and that one arising from the classroom experience. The empirical field of the research comes from the work of the teachers responsible for the formation of the alphabetizers of the GerAção Cidadã Program (2004-2005) linked, as an Extension Program, to Federal University of Rio Grande do Norte. Indeed, it tries to understand how these young and adult educators makers figure out the link between the experienced knowledge, which their lives give testimony of, with the scientific knowledge, which they are entitled to mediate in class. This work is funded in the principles of the Collaborative Research, which constitutes a kind of qualitative research. It makes use of procedures supported by qualitative research, especially those ones related to reflexive sessions, as well as to documental researches and semi-structured interviews. These spaces have afforded the group of alphabetizers the opportunity to talk over their practice, not only individually but also collectively, in order to work out contributive proposals having in view changes in the educative actions. As elaborated contributions, we present a discussion about the specificities in the making of educators to EJA, in their differentiated social roles. Reflecting on the experiences of the educators makers, we highlight those elements we regard as essential to the constitution of a formation proposal, like formative times and spaces, dialogue and social memory. The curricular organization is compreneded as part of an enlarged dimension that does not restraint itself to school; rather, it is visualized as a structuring instance that connects different knowledge surpassing community and university. Under this optics, we come to the conclusion that the connection the scientific knowledge establishes with the experienced one, which is immersed in the cultural practices of those who are involved in the formative process, is the basement to a curricular proposal of a formation course destined to educators committed with the need of changing society

Atuação de técnicos de enfermagem junto ao recém-nascido com dor em uma unidade de terapia intensiva neonatal

The pain is a sensuous and emotional experience unpleasant associated or related to real injury or potencial of the tissues. It is considered an individual and subjective experience generally has been described in the literature about in the neonatal stage a lot. This study has descriptive and exploratory character with a qualitative approach. The study has with objectives to analyze the performance of the nursing technicians working with newborns admitted in the ITUN, seeking to describe the perception of the nursing technicians about the pain, identify the parameters used for the detection and evaluation of pain in them, trying to describe the ons of this team about the pain in the newborns in ITUN. The subjects are nine nursing technicians of the ITU of the Parenting School Januário Cicco in Natal-RN, engaged in direct assistance to newborns in the ITU, on the turn of the morning, which was prepared to participate in the search. The collection of the data was conducted through a structured interview with tree questions; through a non-participatory observation with a structured roadmap and were used to record and pass on call was also as a way of obtaining data. The start of the collection made after the assent of the Ethics Committee / UFRN in November, 2007. The speakings have been transcribed and data read extensively to obtain categories.The analysis of the content made in terms of Bardin. Emerged three main categories of significance: Perceptioning of pain in newborns; Caring for the newborns with pain; Registering the pain in the newborns. A nursing technicians identifies the pain in the newborns, for the most part, so empirical, using signs of behavioral or physiological changes in isolation, giving little emphasis to the environment and to respect that the newborns is inserted. It was found that the attitudes cited by subjects of the search before the newborns with pain, are for the most part non-pharmacological actions such as sucking nutrient not, a proper positioning and measures of comfort, however pharmacological actions have also been reported.These is also the absence of records of nursing records in the report of pain and actions to minimize them and, in records and for the passage of call. With this study we understand the role of the nursing technicians, and seek to contribute to subsidies for the practice of professionals involved in caring for this age group, and also in the search for a humane assistance to the newborns

Uma fundamentação matemática para processamento digital de sinais intervalares

This work deals with a mathematical fundament for digital signal processing under point view of interval mathematics. Intend treat the open problem of precision and repesention of data in digital systems, with a intertval version of signals representation. Signals processing is a rich and complex area, therefore, this work makes a cutting with focus in systems linear invariant in the time. A vast literature in the area exists, but, some concepts in interval mathematics need to be redefined or to be elaborated for the construction of a solid theory of interval signal processing. We will construct a basic fundaments for signal processing in the interval version, such as basic properties linearity, stability, causality, a version to intervalar of linear systems e its properties. They will be presented interval versions of the convolution and the Z-transform. Will be made analysis of convergences of systems using interval Z-transform , a essentially interval distance, interval complex numbers , application in a interval filter.

Fibra de crital fotônico: fundamentação e aplicações

The main purpose of this dissertation, consists of the study and analysis of the PBG (Photonic Band Gap )..tecnology incorporated in optical fiber structures. So, we'l1 present a complete PBG structure theory, and folowing this, we'l1 present also a chapter for convencional optical fiber, due to the need to construct the base theory of them, and latter a more complete work about photonic crystal fiber. Finaly, we'l1 show the results of the signals , dispersion, and obtained curves under the right dimensions according to the required signals, for convencional optical and photonic crystal fiber. Knowing that PBG crystals with low losses act as perfect mirrors for forbidden frequences and knowing that the persence of structures of PBG as substrates, brings some desirable characteristics such as spontaneous emition supression and superficial waves. We' 11 show according to these characteristics its applications in telecomunication. Therefore, the enphasis of this work is to show that the optical fibers are the only practible thing to integrate the enormous quantity of data and video at intemet' s market, developing, manipulating, changing, and multiplexing the optical fibers chanels in an area where we expect that the photonic crystals has an important hole, since the photonic crystals can be projected and made to avoid losses in the bands of certain wavelength which permits the increase in efficiency ofthe optical components projected with crystals. A sequence of this work would be the utilisation of the PBG structures in the new system of optical network without fiber developed by Bell laboratories of the lucent tecnology, last year using light rays for transmiting information through the air. The new system of optical networks without fiber will permit sending the data of 15 cd-rooms in less then one second, what represents 65 times more information than those transmitted through the actual radio frequences

Um estudo de estruturas com PBG e fotônica

One of the objectives of this work is the ana1ysis of planar structures using the PBG (photonic Bandgap), a new method of controlling propagation of electromagnetic waves in devices with dielectrics. Here the basic theory of these structures will be presented, as well as applications and determination of certain parameters. In this work the analysis will be performed concerning PBG structures, including the basic theory and applications in planar structures. Considerations are made related to the implementation of devices. Here the TTL (Transverse Transmission Line) method is employed, characterized by the simplicity in the treatment of the equations that govern the propagation of electromagnetic waves in the structure. In this method, the fields in x and z are expressed in function of the fields in the traverse direction y in FTD (Fourier Transform Domain). This method is useful in the determination of the complex propagation constant with application in high frequency and photonics. In this work structures will be approached in micrometric scale operating in frequencies in the range of T erahertz, a first step for operation in the visible spectra. The mathematical basis are approached for the determination of the electromagnetic fields in the structure, based on the method L TT taking into account the dimensions approached in this work. Calculations for the determination of the constant of complex propagation are also carried out. The computational implementation is presented for high frequencies. at the first time the analysis is done with base in open microstrip lines with semiconductor substrate. Finally, considerations are made regarding applications ofthese devices in the area of telecommunications, and suggestions for future