55 resultados para Revestimentos protetores
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Brazil is the world s leading coffee producer. In 2008, 45.99 million of 60 kg bags of benefited coffee were produced. In the process of improvement 50% is grain and 50% is husk, thus, 1.38 million tons of coffee husk are produced annually. The husk is used as combustible in the drying and improvement ovens in the coffee farms, generating ash as residue. These ashes contain a high concentration of alkaline metals and earth metals, mainly K2O and CaO. This work studies the use of this residue in the ceramic tiles industry, as fluxing agents in substitution to the feldspar. Ten mixtures with equal ratios of clay and kaolin, proceeding from Bahia and the residue (varying from 30 to 5%) were defined and produced in uniaxial tool die of 60x20mm with approximately 5 mm of thickness and 45MPa compacting pressure. The samples were fired in four different temperatures: 1100 °C, 1150 °C, 1185 °C and 1200 °C during 60 minutes and characterized by means of X-ray fluorescence, X-ray diffraction, gravimetric thermal analysis and differential thermal analysis. The results of water absorption, apparent porosity, linear shrinkage, XRD, dilatometry, flexural strength and SEM were also analysed. The test specimen with addition of 10% of ash fired in 1200 °C resulted in 0.18% water absorption and 40.77 MPa flexural strength, being classified as porcelain stoneware tiles according to ABNT, UNI and ISO norms
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Improving the adherence between oilwell metallic casing and cement sheath potentially decrease the number of corrective actions present/y necessary for Northeastern wells submitted to steam injection. In addition to the direct costs involved in the corrective operations, the economic impact of the failure of the primary cementing aIso includes the loss in the production of the well. The adherence between casing and cement is current/y evaluated by a simple shear tests non standardized by the American Petroleum Institute (API). Therefore, the objective of the present is to propose and evaluate a standardized method to assess the adherence of oilwell metallic casing to cement sheath. To that end, a section of a cemented oilwell was simulated and used to test the effect of different parameters on the shear stress of the system. Surface roughness and different cement compositions submitted or not to thermal cycling were evaluated. The results revealed that the test geometry and parameters proposed yielded different values for the shear stress of the system, corresponding to different adherent conditions between metallic casing and cement sheath
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Introduction: Radical prostatectomy surgery is the best treatment currently adopted by detecting prostate cancer. The urinary incontinence is one more common and difficult to treat postoperative complications, which causes a negative impact on quality of life of the individual prostatectomy . The surface electrical nerve stimulation involves the transmission of electrical impulses from an external stimulator for peripheral nerve through surface electrodes attached to skin. It is an easy and efficient technique, widely used for pain relief, rehabilitation and muscle strengthening. Objective: To analyze the effect of T10-L2 percutaneous electrical stimulation, in individuals with urinary incontinence who underwent radical prostatectomy by the laparoscopic technique. Methods: Six patients had previously undergone radical prostatectomy were submitted to 20 sections of surface electrical stimulation with frequency of 4 Hz, pulse width of 1ms during 20 minutes. All subjects fillid a quality of life - International Consultation on Incontinence Questionnaire- Short FormI - ICIQ-SF questionnaire evaluating. Results: Results showed reduction in the use of the number of pads, number of leaks before and after treatment, and reduced voiding frequency and consequent improvement in quality of life. No side effects were reported. Conclusion: Percutanous electrical stimulation in T10-L2 may be an effective technique to treat urinary incontinence (UI) after radical prostatectomy video laparoscopy
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Periodontal disease is a complex inflammatory and infectious condition that immune host, front of the microbial aggressions, can lead to disease progression, resulting in tissue destruction. The tissue damage induces the release of regulatory molecules, which protective roles and / or destructive, including proteins VEGF (vascular endothelial growth factor vascular) and HIF-1 α (hypoxia-induced factor α -1). Thus, this study investigated, quantitatively and comparatively, the immunohistochemical expression of VEGF (vascular endothelial growth factor) and HIF-1 α (hypoxia induced factor 1-α), proteins involved in inflammation, angiogenesis and hypoxia, in human gingival tissues. Therefore, 75 samples of gingival tissues were examined. Thirty samples were chronic periodontitis, 30 with chronic gingivitis and 15 healthy gingival. After sections analysis, positives and negatives inflammatory and endothelial cells in the connective tissue were counted and converted into percentage. Data were statistically analyzed using Kruskal-Wallis test and Spearman correlation. The results showed that both proteins marked. It was observed higher immunoreactivity for HIF-1 α at chronic gingivitis and periodontitis specimens compared to healthy sites, however, no statistically significant differences were observed among them (p>0.05). The VEGF immunostaining showed similarity among the cases of periodontitis, gingivitis and healthy gingiva. Moderate and positive correlation statistically significant differences were verified for the expressions of VEGF and HIF-1α in gingival health (r = 0,529, p = 0.04). Thus, it can be conclude that possibly the route of HIF-1 α, is activated in periodontal disease may have involvement of the protein in pathogenesis and progression of disease, and that activation of VEGF, can be in addition to being triggered transcription by HIF-1 α may be also influenced by other additional factors such as the action of periodontal microorganisms endotoxins
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In this work, the plant species Copernicia prunifera (Miller) H. E. Moore (carnauba), naturally occurring which prevails in the northeast region of Brazil was the subject of studies aiming its use as external coating of pipelines used in petroleum industry. The part of the plant worked were the leaves, also called straw, which were coated with resinous material. For this purpose, it was necessary to evaluate the effectiveness of the use of acrylic resins in the straw carnauba coating. The properties of the untreated carnauba straw and chemically treated with sodium hydroxide, hexane and carbon tetrachloride were investigated by ATRFTIR, SEM and thermal analysis. The first two techniques showed that treatment with solvents has caused major changes in the straw surface, while the thermal analysis indicated that the sodium hydroxide caused variations in thermal stability of straw constituents. Water absorption measurements showed that treatments have accelerated the absorption process and the reduction of contact angle values for treated samples with solvents indicated higher hidrophilicity of straw. The tensile tests showed lower values of elastic modulus and tensile strength for treated samples. Furthermore, coatings using pure commercial resins A and B as well as the formulations with clay were applied in straw and they were examined once again through thermal analysis, water absorption measurements, contact angle and mechanical tests. To analyze the effect of heat ageing, samples were subjected to tensile tests again in order to assess its resistance. The results showed that the resins/clay formulations increased thermal stability of straw, they promoted a good impermeabilization and caused significant decrease in the values of elastic modulus and tensile strength. Evaluating the ageing effect on the mechanical properties, it has been showed good recovery to the coated straw with the formulations A 60 and A 80% in modulus and tensile strength values and elongation at break values have remained very close. It is thus concluded that the carnauba straw can be used as a coating of pipelines with significant cost savings, since there is no need for pretreatment for its use and shows itself as a viable biotechnology alternative, contributing to the quality of coatings material and environment preservation.
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the institutionalized elderly presents for being more fragile a lot of body balance s changes, which can induce falls and health frailty. One of the consequences of it is the appearance of dizziness, vestibular or not. This study aims to identify the risk factors related to dizziness in institutionalized elderly, with and without vestibular disorders, in the city of Natal-RN. Method: a case-control study realized in 12 regulated by Health Surveillance Long Term Care Institutions for the elderly in Natal-RN. Elected seniors with good cognitive level and able to walk, totaling 115 individuals, and of these, 102 were selected according to the presence of dizziness in the last year (n = 51) and their controls (n = 51), paired by sex and age. The 51 elderly patients with dizziness were divided into 3 groups case: case one, for elderly with dizziness and without vestibulopathy (n=38); case two, for elderly with dizziness and vestibulopathy (n=13) and case three, for all the seniors with dizziness, or added to the case 1 case 2 (n=51). The 51 seniors who served as controls were also divided into three groups, according to the number of individuals of each case: control 1, n = 38, control 2, n = 13 control and 3 (sum of 1 control with control 2), n = 51. As possible risk factors were analyzed variables related to characteristics of the institution, to the habits of life of older people and those concerned with the health of the elderly. For statistical analysis, we used the chi-square or Fisher exact test for a significance level of 5% and calculating the association magnitude between variables by measuring the Odds Ratio. Results: as risk factors for dizziness without vestibular disorders were found the presence of hypertension and cardiovascular disease, as well as the presence of three or more disorders for elderly and use of gastric protector drugs. For the elderly group from case two were found no associated risk factor. For elderly patients with dizziness in the case group three, we observed the same risk factors found for the elderly in the case group one, plus the presence of osteoarthritis pathology, which was also significant for this group. Conclusion: dizziness in institutionalized elderly is associated with systemic common diseases in this age group and the vestibulopathy presents itself as pathology on an isolated way, not being possible, with our data, associate it with non-risk factors
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The Brazilian coast has a wide variety of complex environments and ecosystems along the coast, about 80% are represented by sandbanks and dunes. The coastal ecosystems were the first to suffer the impacts man and places, as the very fragile ecosystems, are somehow altered. Are few areas of restinga well as natural features, very few protected in conservation units. Only in the last two decades the Brazilian restinga have been studies that are showing their importance for biodiversity of the country, though its economic importance remains largely unknown. In Rio Grande do Norte in the restinga vegetation and dune environments extend for almost the entire coast. The dunes are distinguished in the coastal landscape of the state due to the exuberance of its forms, heights and coating plants. The dune system is of fundamental importance for the maintenance of coastal urban settlements, especially for the city of Natal, acting on the hydrological dynamics of water table and reducing the effect of wind and movement of grains of sand to the interior and thus avoiding the burial City. However, the ecosystem of restinga and dune environments have been weakened and destroyed according to the intense urbanization and the knowledge of the vegetation of restinga installed on the dunes are still scarce. Thus, the objective of this study was to characterize the structure and floristic composition of vegetation established on a dune in the Dunes State Park Christmas and gather information to develop a model of recovery of the dune ecosystem. This dissertation is composed of 2 chapters, the first being: Structure of the vegetation of the dunes Dunes State Park in Natal, RN with the objective of describing the structure and composition of species of tree-shrub vegetation of restinga dunes of the Parque das Dunas and second: Recovery of degraded areas in a sand dune, which aimed to review the terms and concepts used in the theme of recovery and the techniques for recovery of degraded areas with emphasis on sandy environments and poor in nutrients, reporting some experiences within and external to Brazil the country, mainly in the Northeast and dunes positive and negative aspects that should be followed in building a model to be adopted for the recovery of local dunes
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Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq
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Child development is the result of the interaction of biological, psychological and social factors. Hostile environment, income, offered stimuli, as well as the presence of a chronic illness are issues that may interfere significantly. Considering the chronic diseases, we can identify congenital heart disease (CHD) is characterized by anatomical heart defects and functional and currently has presented an incidence of up to 1% of the population of live births. This research aimed to evaluate child development and verify an association with the commitment by biopsychosocial factors of children with and without CHD. Study participants were children from zero to six years, divided into three groups: Group1- 29 children pre-surgical congenital heart disease, Group2- 43 children post-surgical cardiac patients and Group3- 56 healthy children. The instruments used were a biopsychosocial questionnaire and the Screening Test Denver II. Of the total of 128 children evaluated, 66 (51.56%) are girls, and ages ranged from two months to six years (median 24.5 months). In G1 and G2 predominated acyanotic heart disease (55.2% and 58.1%). Regarding the Denver II reviews, children with heart disease had more development ratings "suspicious" and "suspect/abnormal", and 41.9% of children who have gone through surgery had characterized its development as "suspect/abnormal" . In the group of healthy children 53.6% were classified as developmental profile "normal" (p = ˂0,0001). On the areas of Denver II, among children with heart disease was greatest change in motor areas (p = 0.016, p = ˂0,001). The biopsychosocial variables that were related to a possible developmental delay were gender (p = 0.042), child's age (p = 0.0001) and income per capita (p = 0.019). There were no associations between the variables related to the treatment of disease, information, understanding of the disease and the way parents treat their children. In the group of healthy children showed that children who underwent hospitalization rates were more changes in development (p = 0.025) and the higher the number of admissions over these changes have intensified (p = 0.023). The results suggest that children with congenital heart disease have likely delayed development. It was also observed that there is a significant difference between the children who have gone through surgery, those who are still waiting for surgery only doing clinical follow-up. Changes in the development are more connected motor areas can be explained by the characteristic features of the disease and treatment, such as dyspnea, fatigue, care and limitations in daily activities. The gender and age appear to be decisive in the development as well as healthy children go through hospitalization experience. Already in children with heart disease, it was realized that social variables involved in the disease and the treatment did not affect the development. This question can be understood by means of protective factors and resiliency, as this population receives family and social support.
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In States of Paraíba (PB) and Rio Grande do Norte (RN), northeast of Brazil, the most significant deposits of non-metallic industrial minerals are pegmatites, quartzites and granites, which are located in Seridó region. Extraction of clay, quartz, micas and feldspars occurs mainly in the cities of Várzea (PB), OuroBranco (RN) and Parelhas (RN). Mining companies working in the extraction and processing of quartzite generate large volumes of waste containing about 90% SiO2 in their chemical composition coming from quartz that is one of the basic constituents of ceramic mass for the production of ceramic coating. Therefore, this work evaluates the utilization of these wastes on fabrication of high-quality ceramic products, such as porcelain stoneware, in industrial scale. Characterization of raw materials was based on XRF, XRD, GA, TGA and DSC analysis, on samples composed by 57% of feldspar, 37% of argil and 6% of quartzite residues, with 5 different colors (white, gold, pink, green and black). Samples were synthesized in three temperatures, 1150°C, 1200°C and 1250°C, with one hour isotherm and warming-up tax of 10°C/min. After synthesizing, the specimens were submit to physical characterization tests of water absorption, linear shrinkage, apparently porosity, density, flexural strain at three points. The addition of 6% of quartzite residue to ceramic mass provided a final product with technological properties attending technical norms for the production of porcelain stoneware; best results were observed at a temperature of 1200°C. According to the results there was a high iron oxide on black quartzite, being their use in porcelain stoneware discarded by ethic and structural question, because the material fused at 1250°C. All quartzite formulations had low water absorption when synthesized at 1200°C, getting 0.1% to 0.36% without having gone through the atomization process. Besides, flexural strain tests overcame 27 MPa reaching the acceptance limits of the European Directive EN 100, at 1200°C synthesizing. Thus, the use of quartzite residues in ceramic masses poses as great potential for the production of porcelain stoneware.
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O objetivo deste estudo foi comparar a fusibilidade de ligas de Co-Cr-Mo-W (Remanium 2000), Ni-Cr (Durabond) e Co-Cr-Mo (Vera-PDI), incluídas em revestimentos à base de fosfato, sílica ou utilizando uma técnica mista. Uma rede de nylon quadrada (10 X 10 mm) com 100 espaços abertos serviu de modelo para construção de padrões de cera, que foram incluídos com revestimento à base de sílica, revestimento fosfatado e técnica mista (camada de revestimento fosfatado com 2 mm de espessura + revestimento à base de sílica). Quarenta e cinco espécimes (5 para cada condição experimental) foram fundidos sob chama de gás-oxigênio e a seguir jateados com óxido de alumínio. O número de segmentos fundidos completos foi contado para obter uma percentagem designada como "valor de fusibilidade", representando a precisão da liga em reproduzir os detalhes do molde. A análise estatística por meio de ANOVA a dois critérios e teste Tukey mostrou que, comparando-se as ligas, a Remanium 2000 teve fusibilidade estaticamente semelhante (p>0,05) à da Vera PDI e inferior à da liga Durabond (p<0,05). Considerando os resultados da técnica mista, a liga Remanium 2000 teve menor valor de fusibilidade (p<0,05) que as ligas Durabond e Vera PDI, que apresentaram valores estatisticamente semelhantes entre si (p>0,05). Concluindo, a fusibilidade da liga de Co-Cr-Mo-W (Remanium 2000) foi comparável à da liga de Co-Cr (Vera PDI) e inferior à da liga de Ni-Cr alloy (Durabond). À exceção da liga Remanium 2000, a técnica de inclusão mista aumentou consideravelmente a capacidade das ligas testadas de reproduzir os detalhes do molde, quando comparada à técnica de inclusão em revestimento fosfatado. A técnica de inclusão mista representa uma alternativa para melhorar a fusibilidade de ligas de metais básicos sem afetar a qualidade superficial das peças metálicas.
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O objetivo deste estudo foi comparar a fusibilidade de ligas de Co-Cr-Mo-W (Remanium 2000), Ni-Cr (Durabond) e Co-Cr-Mo (Vera-PDI), incluídas em revestimentos à base de fosfato, sílica ou utilizando uma técnica mista. Uma rede de nylon quadrada (10 X 10 mm) com 100 espaços abertos serviu de modelo para construção de padrões de cera, que foram incluídos com revestimento à base de sílica, revestimento fosfatado e técnica mista (camada de revestimento fosfatado com 2 mm de espessura + revestimento à base de sílica). Quarenta e cinco espécimes (5 para cada condição experimental) foram fundidos sob chama de gás-oxigênio e a seguir jateados com óxido de alumínio. O número de segmentos fundidos completos foi contado para obter uma percentagem designada como "valor de fusibilidade", representando a precisão da liga em reproduzir os detalhes do molde. A análise estatística por meio de ANOVA a dois critérios e teste Tukey mostrou que, comparando-se as ligas, a Remanium 2000 teve fusibilidade estaticamente semelhante (p>0,05) à da Vera PDI e inferior à da liga Durabond (p<0,05). Considerando os resultados da técnica mista, a liga Remanium 2000 teve menor valor de fusibilidade (p<0,05) que as ligas Durabond e Vera PDI, que apresentaram valores estatisticamente semelhantes entre si (p>0,05). Concluindo, a fusibilidade da liga de Co-Cr-Mo-W (Remanium 2000) foi comparável à da liga de Co-Cr (Vera PDI) e inferior à da liga de Ni-Cr alloy (Durabond). À exceção da liga Remanium 2000, a técnica de inclusão mista aumentou consideravelmente a capacidade das ligas testadas de reproduzir os detalhes do molde, quando comparada à técnica de inclusão em revestimento fosfatado. A técnica de inclusão mista representa uma alternativa para melhorar a fusibilidade de ligas de metais básicos sem afetar a qualidade superficial das peças metálicas.
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DUTRA, Ricardo Peixoto Suassuna ; SILVA, Jaquelígia Brito da ; MORAES, Márcio Luiz Varela Nogueira de ; NASCIMENTO, R. M. ; GOMES, Uilame Umbelino ; PASKOCIMAS, Carlos Alberto . Avaliação da potencialidade de argilas do Rio Grande do Norte. Cerâmica Industrial, v. 13, p. 47-50, 2008.
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VARELA, M. L. et al. Influência da adição de resíduo de caulim nas propriedades tecnológicas de uma massa padrão de porcelanato produzido em escala industrial. Cerâmica, v.55, n.334 p.209-215. 2009.ISSN 0366-6913.Disponível em:
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FORMIGA, Felipe Lira et al. Avaliação da Potencialidade de Uso do Resíduo Proveniente da Indústria de Beneficiamento do Caulim na Produção de Piso Cerâmico. Cerâmica Industrial, v. 14, p. 41-45, 2009.