5 resultados para INTERMEDIATE LAYER
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
Pipelines for the transport of crude oil from the production wells to the collecting stations are named production lines . These pipes are subjected to chemical and electrochemical corrosion according to the environment and the type of petroleum transported. Some of these lines, depending upon the composition of the fluid produced, may leak within less than one year of operation due to internal corrosion. This work aims at the development of composite pipes with an external protecting layer of high density polyurethane for use in production lines of onshore oil wells, meeting operational requirements. The pipes were manufactured using glass fibers, epoxy resin, polyester resin, quartz sand and high density polyurethane. The pipes were produced by filament winding with the deposition of high density polyurethane on the external surface and threaded ends (API 15 HR/PM-VII). Three types of pipes were manufactured: glass/epoxy, glass/epoxy with an external polyurethane layer and glass/epoxy with an intermediate layer of glass fiber, polyester, sand and with an external polyurethane layer. The three samples were characterized by Scanning Electronic Microscopy (SEM) and for the determination of constituent content. In addition, the following tests were conducted: hydrostatic test, instant rupture, shorttime failure pressure, Gardner impact, transverse stiffness and axial tension. Field tests were conducted in Mossoró RN (BRAZIL), where 1,677 meters of piping were used. The tests results of the three types of pipes were compared in two events: after two months from manufacturing of the samples and after nine months of field application. The results indicate that the glass/epoxy pipes with an intermediate layer of fiber glass composite, polyester e sand and with an external layer of high density polyurethane showed superior properties as compared to the other two and met the requirements of pressure class, axial tensile strength, transverse stiffness, impact and environmental conditions, for onshore applications as production lines
Resumo:
Cloud computing can be defined as a distributed computational model by through resources (hardware, storage, development platforms and communication) are shared, as paid services accessible with minimal management effort and interaction. A great benefit of this model is to enable the use of various providers (e.g a multi-cloud architecture) to compose a set of services in order to obtain an optimal configuration for performance and cost. However, the multi-cloud use is precluded by the problem of cloud lock-in. The cloud lock-in is the dependency between an application and a cloud platform. It is commonly addressed by three strategies: (i) use of intermediate layer that stands to consumers of cloud services and the provider, (ii) use of standardized interfaces to access the cloud, or (iii) use of models with open specifications. This paper outlines an approach to evaluate these strategies. This approach was performed and it was found that despite the advances made by these strategies, none of them actually solves the problem of lock-in cloud. In this sense, this work proposes the use of Semantic Web to avoid cloud lock-in, where RDF models are used to specify the features of a cloud, which are managed by SPARQL queries. In this direction, this work: (i) presents an evaluation model that quantifies the problem of cloud lock-in, (ii) evaluates the cloud lock-in from three multi-cloud solutions and three cloud platforms, (iii) proposes using RDF and SPARQL on management of cloud resources, (iv) presents the cloud Query Manager (CQM), an SPARQL server that implements the proposal, and (v) comparing three multi-cloud solutions in relation to CQM on the response time and the effectiveness in the resolution of cloud lock-in.
Resumo:
Acute lymphoblastic leukemia (ALL) is the most common form of cancer in children and is responsible for severe stomatologic complications. Treatment consists of four phases of chemotherapy, the main side effect of methotrexate, the drug most used during the intensification phase, is oral mucositis. OBJECTIVE: To evaluate the clinical aspects of the oral mucosa of children with ALL and to determine the effect of 0.12% chlorhexidine gluconate on the prevention of stomatologic complications in these patients. PATIENTS AND METHODS: Thirty-three children treated for ALL ranging in age from 2 to 15 years, without distinction of gender or race, were submitted to visual examination, digital palpation of the oral mucosa and cytologic examination of the buccal mucosa, and divided into two groups: group I consisted of 23 children using an oral solution of 0.12% chlorhexidine gluconate twice a day, and group II consisted of 10 children who did not receive this solution. All children received daily oral hygiene care guided by the dentist throughout treatment. RESULTS: Mucositis was observed in six children of group I and eight of group II, and was characterized by erythema, edema and ulcers. Uniform cytologic findings were obtained for the two groups, with a clear predominance of cells of the intermediate layer in all smears, in addition to a perinuclear halo in 18% of the smears. CONCLUSION: The present results suggest that systematic preventive treatment with 0.12% chlorhexidine gluconate and oral hygiene care reduce the occurrence of oral complications in children with ALL undergoing antineoplastic chemotherapy.
Resumo:
Acute lymphoblastic leukemia (ALL) is the most common form of cancer in children and is responsible for severe stomatologic complications. Treatment consists of four phases of chemotherapy, the main side effect of methotrexate, the drug most used during the intensification phase, is oral mucositis. OBJECTIVE: To evaluate the clinical aspects of the oral mucosa of children with ALL and to determine the effect of 0.12% chlorhexidine gluconate on the prevention of stomatologic complications in these patients. PATIENTS AND METHODS: Thirty-three children treated for ALL ranging in age from 2 to 15 years, without distinction of gender or race, were submitted to visual examination, digital palpation of the oral mucosa and cytologic examination of the buccal mucosa, and divided into two groups: group I consisted of 23 children using an oral solution of 0.12% chlorhexidine gluconate twice a day, and group II consisted of 10 children who did not receive this solution. All children received daily oral hygiene care guided by the dentist throughout treatment. RESULTS: Mucositis was observed in six children of group I and eight of group II, and was characterized by erythema, edema and ulcers. Uniform cytologic findings were obtained for the two groups, with a clear predominance of cells of the intermediate layer in all smears, in addition to a perinuclear halo in 18% of the smears. CONCLUSION: The present results suggest that systematic preventive treatment with 0.12% chlorhexidine gluconate and oral hygiene care reduce the occurrence of oral complications in children with ALL undergoing antineoplastic chemotherapy.
Resumo:
Pipelines for the transport of crude oil from the production wells to the collecting stations are named production lines . These pipes are subjected to chemical and electrochemical corrosion according to the environment and the type of petroleum transported. Some of these lines, depending upon the composition of the fluid produced, may leak within less than one year of operation due to internal corrosion. This work aims at the development of composite pipes with an external protecting layer of high density polyurethane for use in production lines of onshore oil wells, meeting operational requirements. The pipes were manufactured using glass fibers, epoxy resin, polyester resin, quartz sand and high density polyurethane. The pipes were produced by filament winding with the deposition of high density polyurethane on the external surface and threaded ends (API 15 HR/PM-VII). Three types of pipes were manufactured: glass/epoxy, glass/epoxy with an external polyurethane layer and glass/epoxy with an intermediate layer of glass fiber, polyester, sand and with an external polyurethane layer. The three samples were characterized by Scanning Electronic Microscopy (SEM) and for the determination of constituent content. In addition, the following tests were conducted: hydrostatic test, instant rupture, shorttime failure pressure, Gardner impact, transverse stiffness and axial tension. Field tests were conducted in Mossoró RN (BRAZIL), where 1,677 meters of piping were used. The tests results of the three types of pipes were compared in two events: after two months from manufacturing of the samples and after nine months of field application. The results indicate that the glass/epoxy pipes with an intermediate layer of fiber glass composite, polyester e sand and with an external layer of high density polyurethane showed superior properties as compared to the other two and met the requirements of pressure class, axial tensile strength, transverse stiffness, impact and environmental conditions, for onshore applications as production lines