108 resultados para Ligas de aluminio - Tratamento termico


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The aim of this work is the treatment of produced water from oil by using electrochemical technology. Produced water is a major waste generated during the process of exploration and production in the oil industry. Several approaches are being studied aiming at the treatment of this effluent; among them can be cited the biological process and chemical treatments such as advanced oxidation process and electrochemical treatments (electrooxidation, electroflotation, electrocoagulation, electrocoagulation). This work studies the application of electrochemical technology in the treatment of the synthetic produced water effluent through the action of the electron, in order to remove or transform the toxic and harmful substances from the environment by redox reactions in less toxic substances. For this reason, we used a synthetic wastewater, containing a mixture H2SO4 0,5M and 16 HPAs, which are: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo (a) anthracene, chrysene, benzo(b)fluoranthene, benzo(k) fluoranthene, benzo(a)pyrene, indeno(1,2,3-cd)pyrene, dibenzo(a, h)anthracene, benzo(g, h, i)perylene. Bulk electrochemical oxidation experiments were performed using a batch electrochemical reactor containing a pair of parallel electrodes, coupled with a power supply using a magnetic stirrer for favoring the transfer mass control. As anodic material was used, a Dimensionally Stable Anode (DSA) of Ti/Pt, while as cathode was used a Ti electrode. Several samples were collected at specific times and after that, the analysis of these samples were carried out by using Gas Chromatography Coupled to Mass Spectrometry (GC - MS) in order to determine the percentage of removal. The results showed that it was possible to achieve the removal of HPAs about 80% (in some cases, more than 80%). In addition, as an indicator of the economic feasibility of electrochemical treatment the energy consumption was analyzed for each hour of electrolysis, and based on the value kWh charged by ANEEL, the costs were estimated. Thus, the treatment costs of this research were quite attractive

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In this work, the treatment of synthetic wastewaters containing Remazol Red BR (RRB) and Novacron Blue C-D (NB) by anodic oxidation using boron doped diamond anodes (BDD) and Novacron Yellow (YN) using BDD and Platinum (Pt) anodes was investigated. Galvanostatic electrolyses of RRB and NB synthetic wastewaters have led to the complete decolorization removal at different operating conditions (current density, pH and temperature). The influence of these parameters was investigated in order to find the best conditions for dyestuff colour removal. According to the experimental results obtained, the electrochemical oxidation process is suitable for decolorizing wastewaters containing these textile dyes, due to the electrocatalytic properties of BDD and Pt anode. Energy requirements for removing colour during galvanostatic electrolyses of RRB, NB and YN synthetic solutions depends mainly on the operating conditions; for example for RRB, it passes from 3.30 kWh m-3 at 20 mA cm-2 to 4.28 kWh m-3 at 60 mA cm-2 (pH = 1); 15.23 kWh m-3 at 20 mA cm-2 to 24.75 kWh m-3 at 60 mA cm-2 (pH = 4.5); 10.80 kWh m-3 at 20 mA cm-2 to 31.5 kWh m-3 at 60 mA cm-2 (pH = 8) (data estimated per volume of treated effluent). In order to verify the Brazilian law regulations of NB and RRB synthetic solutions after electrochemical decolourisation treatment, Hazen Units values were determined and the total colour removal was achieved; remaining into the regulations. Finally, electrical energy cost for removing colour was estimated

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The present study utilized the thermogravimetry (TG) and optical emission spectroscopy with inductively coupled plasma - ICP / OES to determine the calcium content in tablets of carbonate, citrate and calcium lactate used in the treatment of osteoporosis. The samples were characterized by IR, SEM, TG / DTG, DTA, DSC and XRD. The thermal analysis evaluated the thermal stability and physical-chemical events and showed that the excipients influence the decomposition of active ingredients. The results of thermogravimetry indicated that the decomposition temperature of the active CaCO3 (T = 630.2 °C) is lower compared to that obtained in samples of the tablets (633.4 to 655.2 °C) except for sample AM 2 (Ti = 613.8 oC). In 500.0 °C in the samples of citrate and calcium lactate, as well as their respective active principles had already been formed calcium carbonate. The use of N2 atmosphere resulted in shifting the initial and final temperature related to the decomposition of CaCO3. In the DTA and DSC curves were observed endo and exothermic events for the samples of tablets and active ingredients studied. The infrared spectra identified the main functional groups in all samples of active ingredients, excipients and tablets studied, such as symmetric and asymmetric stretches of the groups OH, CH, C = O. Analysis by X-ray diffraction showed that all samples are crystalline and that the final residue showed peaks indicative of the presence of calcium hydroxide by the reaction of calcium oxide with moisture of the air. Although the samples AM 1, AM 2, AM 3 and AM 6 in their formulations have TiO2 and SiO2 peaks were not observed in X-ray diffractograms of these compounds. The results obtained by TGA to determine the calcium content of the drugs studied were satisfactory when compared with those obtained by ICP-OES. In the AM 1 tablet was obtained the content of 35.37% and 32.62% for TG by ICP-OES, at 6 AM a percentage of 17.77% and 16.82% and for AM 7 results obtained were 8.93% for both techniques, showing that the thermogravimetry can be used to determine the percentage of calcium in tablets. The technique offers speed, economy in the use of samples and procedures eliminating the use of acid reagents in the process of the sample and efficiency results.

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TiTanate NanoTubes (TTNT) were synthesized by hydrothermal alkali treatment of TiO2 anatase followed by repeated washings with distinct degrees of proton exchange. TTNT samples with different sodium contents were characterized, as synthesized and after heattreatment (200-800ºC), by X-ray diffraction, scanning and transmission electron microscopy, electron diffraction, thermal analysis, nitrogen adsorption and spectroscopic techniques like FTIR and UV-Vis diffuse reflectance. It was demonstrated that TTNTs consist of trititanate structure with general formula NaxH2−xTi3O7·nH2O, retaining interlayer water in its multiwalled structure. The removal of sodium reduces the amount of water and contracts the interlayer space leading, combined with other factors, to increased specific surface area and mesopore volume. TTNTs are mesoporous materials with two main contributions: pores smaller than 10 nm due to the inner volume of nanotubes and larger pores within 5-60 nm attributed to the interparticles space. Chemical composition and crystal structure of TTNTs do not depend on the average crystal size of the precursor TiO2-anatase, but this parameter affects significantly the morphology and textural properties of the nanostructured product. Such dependence has been rationalized using a dissolution-recrystallization mechanism, which takes into account the dissolution rate of the starting anatase and its influence on the relative rates of growth and curving of intermediate nanosheets. The thermal stability of TTNT is defined by the sodium content and in a lower extent by the crystallinity of the starting anatase. It has been demonstrated that after losing interlayer water within the range 100-200ºC, TTNT transforms, at least partially, into an intermediate hexatitanate NaxH2−xTi6O13 still retaining the nanotubular morphology. Further thermal transformation of the nanostructured tri- and hexatitanates occurs at higher or lower temperature and follows different routes depending on the sodium content in the structure. At high sodium load (water washed samples) they sinter and grow towards bigger crystals of Na2Ti3O7 and Na2Ti6O13 in the form of rods and ribbons. In contrast, protonated TTNTs evolve to nanotubes of TiO2(B), which easily convert to anatase nanorods above 400ºC. Besides hydroxyls and Lewis acidity typical of titanium oxides, TTNTs show a small contribution of protonic acidity capable of coordinating with pyridine at 150ºC, which is lost after calcination and conversion into anatase. The isoeletric point of TTNTs was measured within the range 2.5-4.0, indicating behavior of a weak acid. Despite displaying semiconductor characteristics exhibiting typical absorption in the UV-Vis spectrum with estimated bandgap energy slightly higher than that of its TiO2 precursor, TTNTs showed very low performance in the photocatalytic degradation of cationic and anionic dyes. It was concluded that the basic reason resides in its layered titanate structure, which in comparison with the TiO2 form would be more prone to the so undesired electron-hole pair recombination, thus inhibiting the photooxidation reactions. After calcination of the protonated TTNT into anatase nanorods, the photocatalytic activity improved but not to the same level as that exhibited by its precursor anatase

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The aim of this work was to study a series of 11 different compositions of Ti-Zr binary alloys resistance to aggressive environment, i. e., their ability to keep their surface properties and mass when exposed to them as a way to evaluate their performance as biomaterials. The first stage was devoted to the fabrication of tablets from these alloys by Plasma-Skull casting method using a Discovery Plasma machine from EDG Equipamentos, Brazil. In a second stage, the chemical composition of each produced tablet was verified. In a third stage, the specimen were submitted to: as-cast microstructure analysis via optical and scanning electron microscopy (OM and SEM), x-ray dispersive system (EDS) chemical analysis via SEM, Vickers hardness tests for mechanical evaluation and corrosion resistence tests in a 0.9% NaCl solution to simulate exposition to human saliva monitored by open circuit potential and polarization curves. From the obtained results, it was possible to infer that specimens A1 (94,07 wt% Ti and 5,93% wt% Zr), A4 (77,81 wt % Ti and 22,19 wt % Zr) and A8 (27,83 wt% Ti and 72,17 wt% Zr), presented best performance regarding to corrosion resistance, homogeneity and hardness which are necessary issues for biomaterials to be applied as orthopedic and odontological prosthesis

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During the storage of oil, sludge is formed in the bottoms of tanks, due to decantation, since the sludge is composed of a large quantity of oil (heavy petroleum fractions), water and solids. The oil sludge is a complex viscous mixture which is considered as a hazardous waste. It is then necessary to develop methods and technologies that optimize the cleaning process, oil extraction and applications in industry. Therefore, this study aimed to determine the composition of the oil sludge, to obtain and characterize microemulsion systems (MES), and to study their applications in the treatment of sludge. In this context, the Soxhlet extraction of crude oil sludge and aged sludge was carried out, and allowing to quantify the oil (43.9 % and 84.7 % - 13 ºAPI), water (38.7 % and 9.15 %) and solid (17.3 % and 6.15 %) contents, respectively. The residues were characterized using the techniques of X-ray fluorescence (XRF), Xray diffraction (XRD) and transmission Infrared (FT-IR). The XRF technique determined the presence of iron and sulfur in higher proportions, confirming by XRD the presence of the following minerals: Pyrite (FeS2), Pyrrhotite (FeS) and Magnetite (Fe3O4). The FT-IR showed the presence of heavy oil fractions. In parallel, twelve MES were prepared, combining the following constituents: two nonionic surfactants (Unitol L90 and Renex 110 - S), three cosurfactants (butanol, sec-butanol and isoamyl alcohol - C), three aqueous phase (tap water - ADT, acidic solution 6 % HCl, and saline solution - 3.5 % NaCl - AP) and an oil phase (kerosene - OP). From the obtained systems, a common point was chosen belonging to the microemulsion region (25 % [C+S] 5 % OP and AP 70 %), which was characterized at room temperature (25°C) by viscosity (Haake Rheometer Mars), particle diameter (Zeta Plus) and thermal stability. Mixtures with this composition were applied to oil sludge solubilization under agitation at a ratio of 1:4, by varying time and temperature. The efficiencies of solubilization were obtained excluding the solids, which ranged between 73.5 % and 95 %. Thus, two particular systems were selected for use in storage tanks, with efficiencies of oil sludge solubilization over 90 %, which proved the effectiveness of the MES. The factorial design delimited within the domain showed how the MES constituents affect the solubilization of aged oil sludge, as predictive models. The MES A was chosen as the best system, which solubilized a high amount of aged crude oil sludge (~ 151.7 g / L per MES)

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The aim of this controlled trial was to evaluate the effectiveness of counseling in pain, function and well-fare outcomes on the management of patients with temporomandibular disorder (TMD). Therefore, 51 consecutive patients were allocated to one of the research groups. In Group I, was instituted counseling therapy for Group II was conducted treatment as usual with occlusal splint. Patients were followed for returns at 7, 15, 30 and 60 days after baseline. At baseline, all patients were examined and assessed RDC/TMD form, which was administered by a single trained and calibrated examiner, in addition, the patients were referred for specific treatment according to the group to which belonged. The clinical and functional impairment was assessed at each visit through the Temporomandibular Index (TMI). In each session, the patients were also surveyed about pain intensity using a Visual Analogue Scale (VAS). To analyze the impact of pain on quality of life, OHIP-14 questionnaire was used. The results showed 26 patients in Group I with a mean age of 35.15 ± 10.79 years. 25 patients were allocated to Group II. The mean age was 27.36 ± 10.34 years. The counseling was effective in reducing the intensity of pain (VAS), with significant improvement observed at 7 day follow-up (p <0.001). The functional impairment (TMI) showed significant results at 15 days follow-up (p = 0.002). Counseling was also responsible for significant improvement in the impact of TMD on quality of life (OHIP-14) at all times of the analysis (p <0.001). When comparing research groups, no significant difference was observed for any of the analyzed indices (p> 0.05) nor in the short term (7 days) neither in long term (60 days). It was concluded therefore that, for the studied sample, counseling consisted in an effective treatment option for the control of signs and symptoms of TMD, with results in the short and long term similar to the usual treatment group.

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Tem sido demonstrado que o diabetes influencia no desenvolvimento e progressão da doença periodontal. Acredita-se ainda que há uma relação bi-direcional entre o Diabetes Mellito e a Doença Periodontal. Por isso, o tratamento periodontal pode responder de forma diferente em pacientes com e sem o quadro de diabetes. O objetivo desse estudo foi avaliar clinicamente o efeito da terapia periodontal não cirúrgica em pacientes com periodontite e diabetes mellito (grupo teste) e sem o quadro de diabetes (grupo controle). Para isso, realizou-se o tratamento periodontal não-cirúrgico FMSRP (Full mouth Scalling and Root Planing) e verificou-se os parâmetro clínicos periodontais (profundidade de sondagem, nível clínico de inserção, mobilidade, índice gengival e índice de placa) no início do estudo e após 3 meses. Na análise estatística, o paciente foi considerado como unidade de análise (p<0,05). Para as variáveis categóricas utilizou-se o teste de Fisher. Nas comparações inter-grupo, foi utilizado o Mann-Whitney Test e para comparações intra-grupo (baseline e três meses) utilizou-se o Teste de Wilcoxon. Participaram 26 pacientes no grupo controle e 14 no grupo teste. O índice de placa era 71,20% no início do estudo para o grupo teste e ficou 47,12% no fim; já no controle, os valores eram de 48,52% passando para 37,50%. E o índice gengival no grupo teste no baseline era 42,67 diminuindo para 26,81 e no grupo controle diminuiu de 41,36 para 30,62. A profundidade de sondagem foi no grupo teste 2,71mm passando para 2,40mm; já no controle, os valores foram de 2,84mm diminuindo para 2,55mm. O grupo controle ganhou 0,34 mm de inserção e o grupo teste perdeu 0,44mm de inserção. A recessão gengival aumentou 0,33mm no grupo teste e 0,04mm no grupo controle após os 3 meses. Houve diferença significativa inter-grupo para o índice de placa e gengival no baseline, também foi encontrado na recessão após 3 meses; já intra-grupo verificou-se diferença significativa para todas as variáveis, exceto para o nível clinico de inserção e mobilidade. Quando se categorizou a profundidade de sondagem em ≤3mm, >3 e≤6mm e >6mm, não foi encontrado diferença entre os grupos, mas verificou-se diferença significativa entre os períodos tanto para o grupo teste como para o controle. A hemoglobina glicada no grupo controle foi de 5,90% e no teste aumentou de 7,79% para 8,10%. Portanto, verifica-se que há uma melhora dos parâmetros clínicos periodontais em ambos os grupos, contudo não se verificou uma diferença significativa entre eles. Não obstante, o FMSRP promove um efeito benéfico em relação à condição de saúde periodontal, melhora dos parâmetros clínicos periodontais, em curto prazo (3 meses) tanto em indivíduos diabéticos como em não diabéticos, não sendo possível observar um melhor quadro glicêmico nos diabéticos

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It has been shown that the development of peri-implant mucositis is associated with biofilm accumulation. It is believed that the therapeutic approaches used in periodontal disease may have a positive effect in the cases of peri-implant disease. The aim of this study was to evaluate the effectiveness of non-surgical treatment of peri-implant mucositis, with or without the use of chlorhexidine 0,12% in subjects rehabilitated with osseointegrated implants. Thus, patients were randomly divided into test group (chlorhexidine surgical therapy) and control (non-surgical treatment). This therapy consisted of an adaptation of the (Full Mouth scalling and Root Planing) nonoperative protocol FMSRP, but without the use of ultrasound. The visible plaque index (VPI), gingival bleeding index (GBI), probing depth (PD), bleeding on probing (BOP) and keratinized mucosa clinical parameters were evaluated at baseline and at different times after treatment. The data were not normally distributed and the implant was considered the sampling unit. Data were analyzed using Fri edman and Wilcoxon chi-square (=5%), tests using the Statistical Package for Social Sciences 17.0 (SPSS). Thus, 119 implants were evaluated, 61 in the test group and 58 in the control group. The results showed statistically significant differences for the variables: average BTI implants in both groups (p<0,001), mean ISG implants both in the test group (p<0,001), and control (p= 0,006) of implants; PS for the test group (p< 0,001) and control (p = 0,015) and SS (p<0,001) in the two treatment groups. However, there was no statistically significant difference when the groups were compared. The PS and SS variables showed no statistically significant difference in any of independent interest to the study (age, sex, smoking, treatment group, keratinized mucosa at different times, peri-implant biotype, average VPI implants and GBI). Thus, it can be concluded that both the mechanical treatment isolated as its association with chlorhexidine mouthwash 0.12% can be used for the treatment of peri-implant mucositis. Moreover, the condition of oral h ygiene has improved between baseline and six months and the depth and bleeding on probing decreased after three and six months

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This work deals with an analysis related to the social worker s practice in the oncology area. It aims to identify demands, work conditions as well as current challenges related to this profession. It considers the specificities of breast cancer and relates it to political decisions in the health sector considering the concept of contemporary capitalism. The study analyzes professional action and the demands presented by breast cancer patients who are currently in treatment in Hospital Dr. Luiz Antônio em Natal-Rio Grande do Norte-Brazil. The methodological procedures considered of documental analysis, semi-structured interviews (with two social workers that work with fifteen breast cancer patients) as well as participant observation; which was done counting with my own professional practice in the oncology area. Thus, the research also discusses the breast cancer issue in the life of the users considering their social-economical, cultural and political determinants. Factors such as age in which the diagnosis was known, the relation user/social workers, number of children, rights of the oncology patient, place where he/she lives, education, civil status, (re)insertion of the professional in the work field, perception of self-esteem and bio-psycho-social representation of breast cancer in the lives of these women, all of which were dealt with in this research

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The treatment for abusive users of alcohol and other drugs suffered significant modifications until arriving to the psychosocial model that is used by Centro de Atenção Psicossocial CAPSad II Eastern Natal/RN (Psychosocial Support Center). That model appears starting from Brazilian sanitary and psychiatric reforms which are expressed in the principles and propositions of Sistema Único de Saúde SUS (Unique System of Health). The Psychiatric Reform meant a rupture with the mental hospital and hospital centered treatment pattern which was destined to the abusive users of alcohol and other drugs. The new proposal offers the universalization, democratization, regionalization and completeness of the actions in the field of mental health. It gathers a strictly interdisciplinary health staff. The purpose of this study is to evaluate the effectiveness of the treatment for abusive users of alcohol and other drugs offered by CAPSad II Eastern Natal/RN. The evaluation used, as priority, the qualitative social research through an evaluating study starting from the non-experimental model. The methodological process used different instruments of data collection: bibliographical and documental researches, systematic observations at CAPSad II Eastern Natal/RN and, mainly, the semistructured interviews (21) that were accomplished with the professionals, users and relatives of CAPSad II Eastern Natal/RN. The investigation showed the effectiveness of the service and, therefore, CAPSad II Eastern Natal/RN constitute itself as the main confronting strategy to the mental hospital and hospital centered treatment pattern of caring the abusive users of alcohol and other drugs

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This work performs an algorithmic study of optimization of a conformal radiotherapy plan treatment. Initially we show: an overview about cancer, radiotherapy and the physics of interaction of ionizing radiation with matery. A proposal for optimization of a plan of treatment in radiotherapy is developed in a systematic way. We show the paradigm of multicriteria problem, the concept of Pareto optimum and Pareto dominance. A generic optimization model for radioterapic treatment is proposed. We construct the input of the model, estimate the dose given by the radiation using the dose matrix, and show the objective function for the model. The complexity of optimization models in radiotherapy treatment is typically NP which justifyis the use of heuristic methods. We propose three distinct methods: MOGA, MOSA e MOTS. The project of these three metaheuristic procedures is shown. For each procedures follows: a brief motivation, the algorithm itself and the method for tuning its parameters. The three method are applied to a concrete case and we confront their performances. Finally it is analyzed for each method: the quality of the Pareto sets, some solutions and the respective Pareto curves

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The current environmental crisis demands transformations in the relations among society, nature and development, considering sustainability. In this context, an important theme is replacing fossil fuels with biofuels, such as biodiesel. Moringa oleifera Lam. is a species that can be used as a raw material to produce biodiesel. Besides, it is a multiple purposes plant, which can be used also in water treatment. Thus, the aims of this work were to analyze the anatomical adaptations found in the stem and in the leaf and the seed s oil stores of M. oleifera., to investigate chemical characteristics of M. oleifera s seed oil, considering biodiesel production, and to evaluate the coagulation activity of these seeds in water treatment. Semipermanent histological laminas were made and it follows that the stem has thick cuticle, stomata whose cells guard are below the epidermis line, hollow medulla, druses and tector trichomes as adaptations to climate and soil conditions in which the species is found and the leaf is dorsiventral and it has thick cuticle, tector trichomes and druses. The seed has great reserves of oil. These features favor the use of Moringa oleifera Lam. as a raw material to produce biodiesel in Brazil s Northeast semiarid region. Chemical analysis were made through oil solvent extraction using mechanic stirrer. The oil was analyzed in UV spectrophotometer. A transesterification was made and biodiesel was analyzed in gas chromatography. Oil yield was high and good quality biodiesel was obtained. To evaluate seeds coagulantion activity, coagulation and flocculation essays in jartest were made, using seed extract to treat raw water. Seeds were efficient in cogulation process to treat water. So, they can be used in rudimentary systems or as a raw material to coagulant proteins extraction, as an alternative to traditional coagulants. M. oleifera has characteristics that favor its use to biodiesel production and water treatment

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A epidemia do HIV/AIDS tem desafiado tanto a biomedicina como a ciência de modo geral. Tecnologias vêm sendo exploradas a fim de criar uma base terapêutica consistente às pessoas infectadas. Se os tratamentos exigem o consumo diário de medicamentos, os exames laboratoriais contemplam uma rotina a ser sempre mantida. Levam a um processo de mudança e adaptação pessoal junto de uma reorganização intensiva das formas de cuidado do corpo. As práticas clínico-terapêuticas devem ser entendidas, porém, como elementos particulares de processos culturais de grande alcance. Partindo de pesquisa etnográfica no Rio de Janeiro, discuto os efeitos sociais da biomedicina como um saber e uma cultura global sobre práticas sociais locais.