Pipe Viscometer for Continuous Viscosity and Density Measurement of Oil Well Barrier Materials

The barrier material is a crucial component for wells, as it provides mechanical support to the casing and prevents the uncontrolled flow of formation fluids, ensuring zonal isolation. One of the essential prerequisites for the success of cementing an oil and gas well is the efficient removal of in-situ fluids and their adequate replacement by the barrier material. The quality of the mud displacement is affected by both the density and the viscosity hierarchy among subsequent fluids. Consequently, accurate and reliable measurement of fluid properties can help ensure consistent large-scale mixing of cementing fluids and verification that the properties of the mixed fluid are according to plan. In this paper, we investigate the implementation of a pipe viscometer for future automated measurements of density and viscosity of materials for zonal isolation and perform a sequential validation of the viscometer that starts with small-scale batch mixing and characterization of particle-free calibration liquids, followed by conventional Class G cement and selected new barrier materials. Finally, a larger-scale validation of the pipe viscometer was performed by integrating it into a yard-scale batch mixer for in-line characterization of expanding Class G oilwell cement mixing. In all cases, flow curves derived from pipe viscosity measurements were compared with offline measurements using a rheometer and a conventional oilfield viscometer. After a series of measurements and comparisons, the investigated in-line measurement system proved adequate for viscosity estimation. The flow curve of the barrier materials showed results similar to measurements using a conventional viscometer, validating the proposed test configuration to continuously measure the rheological behavior of the barrier material. The pipe viscometer flow curves are generally found to be in good quantitative agreement with independent viscometer characterization of the fluids, although some of the pipe viscometer measurements likely exhibited entrance length effects. Future improvements to the pipe viscometer design involve the assessment of even longer pipe sections to allow full flow development at the highest shear rate range and possibly different pipe diameters to improve the measurement resolution of low-shear rate viscosity.publishedVersio

O regime internacional dos refugiados e o compliance pelo Estado brasileiro: da evolução do instituto do refúgio à atuação do Brasil no séc. XXI

The refugee issue has obtained gradually more importance in the international system. The problem addresses sensitive issues, such as the protection of the human rights from people who are victims of persecution. However, the national interests are often prioritized leaving the humanitarian aspects aside to the detriment of the political-economical. The UNHCR, international organization responsible for the protection of the refugees, faces several challenges in the performance of its activities, either because of the large number of people who need their assistance, or due to the lack of cooperation and solidarity on the part of the States. To reverse this problematic framework in which the refugee is seen as a threat to national security, attention should be drawn to the fact that refugees are not escaping by choice but to safeguard their lives. Thus, the present work, performed through the qualitative method, aims to analyze the commitment of the Brazilian State to the responsibilities assumed upon ratification of the 1951 Convention and the 1967 Protocol Relating to the Status of Refugee. In order to do so, it was explained at first, the concept and the role of international regimes, presenting the mechanisms of verification, compliance and enforcement and deepening the debate on regime theory. Next, the refugee regime was approached from a historical-normative evolution, mentioning the link between the institutes of asylum and refuge and dealing with the UNHCR’s work. Finally, we sought to understand how Brazil is inserted in this context, examining its performance in the regime based on the logic of compliance with the agreements and highlighting the weaknesses of the Brazilian refugee policy.A questão dos refugiados vem obtendo cada vez mais relevância no sistema internacional. O problema aborda questões delicadas, como a proteção aos direitos humanos de pessoas vítimas de perseguição. No entanto, os interesses estatais muitas vezes falam mais alto, deixando a questão humanitária de lado em detrimento da questão político-econômica. O ACNUR, organização internacional responsável pela proteção aos refugiados, enfrenta diversos desafios na sua atuação, seja em razão do vultuoso contingente de pessoas que necessitam da sua assistência, ou devido à falta de cooperação e solidariedade por parte dos Estados. Para reverter esse quadro problemático, no qual o refugiado é visto como uma ameaça à segurança nacional, deve-se chamar atenção para o fato de que os refugiados não estão fugindo por opção, mas para resguardar as suas vidas. Dessa forma, o presente trabalho, realizado através do método qualitativo, visa analisar o comprometimento do Estado brasileiro para com as responsabilidades assumidas quando da ratificação da Convenção de 1951 e do Protocolo de 1967 sobre o Estatuto dos Refugiados. Para tanto, foi explicado em um primeiro momento o conceito e função dos regimes internacionais, apresentando o que são os mecanismos de verificação, compliance e enforcement e aprofundando o debate sobre a teoria de regimes. Em seguida, abordou-se o regime dos refugiados a partir de uma evolução histórico-normativa, mencionando a ligação entre os institutos do asilo e do refúgio e tratando da atuação do ACNUR. Por fim, buscou-se compreender como o Brasil se insere nesse contexto, examinando sua atuação no regime a partir da lógica de cumprimento dos acordos e evidenciando as fragilidades da política brasileira de proteção aos refugiados

Surgery of frontal sinus fractures. Epidemiologic study and evaluation of techniques

SummaryThe frontal sinus trauma is not rare and it is 8% of the facial fractures. It can affect the anterior and/or posterior plates, with or without hitting the nasofrontal duct. It has a large potential of complications and its management still being a controversy. Objective: To present the casuistic of fractures frontal sinus, the epidemiology and clinical and surgical management of frontal sinus fractures. Materials and Methods: Not randomized retrospective study of 24 patients with frontal sinus fractures Hospital of Clinics, School of Medicine Botucatu, São Paulo, Brazil. Results: From the 24 patients, we had 16 (66,6%) fractures of the extern plate and 8 (33,4%) of both. In 2 patients the nasofrontal duct was involved. Others facial fractures were associated in 20 (83,4%) cases and major lesions of the cerebral segment were found in 13 (54,2%). Subpalpebral incision was performed in the majority with satisfactory aesthetic results. The basis of the surgical treatment was reduction and fixation with different materials (steel wire, mononylon, titanium miniplates) and if necessary we used alogen implants or parietal bone to reconstruct the anterior plate. Conclusion: The principal cause of frontal sinus fractures is crashed car. The management depends of the complexity, because commonly there are cranioencephalic lesions associated. The surgical thecniques used are the incisions, bicoronal flap or browglabella, infra-orbital rim (“butterfly”), associated a endoscopy sinus surgery in cases of infection, cerobrospinal fluid leak and orbital complications

The effect of PVA microfiber reinforcement on the mechanical and rheological behavior of class G oil well cement pastes

During the life cycle of an oil well, the annular cement sheath will be exposed to load combinations that can result in failure. To enhance the structural integrity and ductility of the cement paste, and to improve the resistance to tensile crack propagation, fiber reinforcement can be used. In the present work, the effects of different polyvinyl alcohol (PVA) fiber concentrations on the rheological and mechanical properties of a class G oil well cement paste was investigated. The study focuses on impacts of fibers on the cement paste viscosity, its confined and unconfined stress–strain responses, and resistance to shear and bending loads. An increase in the effective viscosity of the cement paste with increasing fiber content was observed, although the impact was minor for the smallest (semi-dilute) fiber concentration. All cement paste specimens showed a modest frictional strengthening with increasing confining pressure, with the fiber reinforced samples exhibiting improved post-peak load-bearing capacity compared to the base formulation with no fiber additive. Fibers were found to significantly improve cement paste resistance to shear and bending loads, to enhance the toughness and to arrest tensile crack growth. Despite all the benefits already known about adding fibers, for application in the oil and gas industry, it is essential to evaluate the rheology of the mixture that will directly impact pumpability and placement. In this work, flow curves were measured only for concentrations ranging from 0.1% to 0.5% since the other cases approached the concentrated suspension regime with the fluid behaving like a plug. Still, the results elucidate the potential benefits of adding even a relatively small concentration of high-aspect-ratio PVA fibers to oil well cement pastes, particularly for enhancing early-age cement’s shear and bending strength.The effect of PVA microfiber reinforcement on the mechanical and rheological behavior of class G oil well cement pastespublishedVersio

Effects of Different Irrigation Solutions and Protocols on Mineral Content and Ultrastructure of Root Canal Dentine

Introduction: The aim of this study was to evaluate the effect of different irrigating solutions and irrigation protocols on the chemical and physical structure of root dentin. Materials and Methods: Thirty extracted single-rooted human teeth were selected and then distributed into the following treatment groups (n=10): G1, saline solution (0.9% NaCl); G2, 2.5% NaOCl + 17% EDTA + 2.5% NaOCl; G3, 2.5% NaOCl + 9% Etidronate (HEBP) + 2.5% NaOCl; G4, mixture of 5% NaOCl + 18% HEBP; G5, 2.5% NaOCl + 17% EDTA + 0.9% NaCl, and G6, 2.5% NaOCl + 9% HEBP + 0.9% NaCl. The ultrastructure of dentin was characterized through scanning electron microscopy (SEM) and energy dispersive x-ray spectrometry (EDS) determined the chemical composition in terms of the calcium (Ca), phosphorus (P), magnesium (Mg) and potassium (K) content and the Ca/P ratio; and the crystalline phase was analyzed by x-ray diffraction (XRD). A descriptive analysis was performed on the ultrastructure and the crystallography data of dentin. Data analysis included a chemical composition analysis of variance (one-way ANOVA) and a subsequent multiple comparison test (Tukey’s test). Results: Except for the control group, all groups showed morphological changes upon visualization with SEM. For EDS, G2 and G5 showed significant mineral loss and changes in the Ca/P ratio (P<0.05); the highest values of Ca and P were observed in G3, G4 and G6. Conclusion: All the irrigating solutions and irrigation protocols tested promoted changes in the morphology and physical and chemical composition of the dentin. However, no significant differences were observed crystallographically.Keywords: Chelating agent; Dentin; Root Canal Irrigant; Surface Propertie

Infrared Thermography in the Evaluation of Dental Socket Healing After Photobiomodulation Therapy: A Case Report

Introduction: The aim of this article was to evaluate the efficacy of photobiomodulation therapy (PBMT) in the alveolar tissue healing process post-extraction using infrared thermography (IT).Case Presentation: A 36-year-old male patient had teeth extractions (18 and 28). Four PBMT sessions (660 nm; 2 J per tooth) were performed in the region of tooth 28 and recorded with thermographic images to compare the healing process, bilaterally. In the first two postoperative sessions, the temperature was higher (hyperradiant) on the left side (treated). After the third laser application, the left side was hyporradiant. In a later session, the treated side became hyperradiant compared to the control side. The alveolus of tooth 28 showed more rapid healing than tooth 18 over a period of 60 days.Conclusion: IT can be used to detect the favorable effect of PBMT on accelerating the healing process in the alveolus within 60 days after the tooth extraction. DOI: 10.34172/jlms.2021.1

Análise de aplicação do mapeamento de processos na gestão de produção de uma empresa de eletrodomésticos

No mundo atual, as empresas vêm assumindo um papel importante na economia do país e presenciando um crescimento que exige dedicação e busca por novas tecnologias, ferramentas de gestão e empreendedorismo para a realização de diagnósticos periódicos nos métodos e processos utilizados para melhorarem as técnicas de organização de uma determinada empresa, desde a base até o atendimento ao cliente. Neste resumo expandido, o mapeamento de processos compõe uma simbologia de identificação de fluxo, onde visualizamos as etapas chaves dentro de um processo logístico. A necessidade de conhecer as etapas deste processo logístico resulta no conceito e na metodologia aplicada. A empresa analisada pertence ramo de eletrodomésticos, situada na cidade de Teófilo Otoni - MG. Foram abordados conceitos teóricos e descritivos para contribuírem na identificação das etapas funcionais a partir da elaboração de um fluxograma para os setores críticos das etapas que compõe a venda de seus produtos. A conclusão deste projeto irá gerar informações que contribuirão com as propostas na melhoria da qualidade e no serviço de atendimento ao cliente.São Cristóvão, S

O QUE HÁ DE RACIONAL NA RAZÃO DO DIREITO? UMA ANÁLISE DA DOGMÁTICA JURÍDICA E SEU REFLEXO NA DECISÃO JUDICIAL

O pensamento racional é uma forma de interpretar o mundo. O homem desenvolveu-o e forneceu-lhe amplitudes diversas que se estendem em distintas perspectivas do conhecimento jurídico e social. No âmbito da dogmática jurídica, a preocupação central é a valorização dos aspectos lógico-formais das regras de aplicação do Direito positivo. Contudo, o Direito na contemporaneidade imerso em uma sociedade complexa e plural demanda uma interpretação mais ampla da realidade. Com efeito, vários fatores influenciam no processo de decisão, como por exemplo, acepções de ordem moral, religiosas, ideológicas, partidárias, dentre outras. A objetividade normativa passa a conviver com a indeterminação de certos conceitos de ordem valorativa. Nesse sentido, um dos grandes desafios da comunidade jurídica é tentar equacionar a segurança proporcionada pela dogmática jurídica com os critérios de incerteza e indeterminação enquanto elementos valorativos em um dado contexto social. Diante desse cenário, o problema central da pesquisa é analisar a racionalidade jurídica em sua razão prática. Isto é, como autoridades judiciais sob uma forma argumentativa sustentam uma crença no Direito racional. No que concerne à metodologia, a presente pesquisa possui a natureza explicativa no sentido de que objetiva propor reflexões necessárias ao campo do Direito através de uma discussão de ordem teóric

Análise de aplicação do mapeamento de processos na gestão de produção de uma empresa de eletrodomésticos

No mundo atual, as empresas vêm assumindo um papel importante na economia do país e presenciando um crescimento que exige dedicação e busca por novas tecnologias, ferramentas de gestão e empreendedorismo para a realização de diagnósticos periódicos nos métodos e processos utilizados para melhorarem as técnicas de organização de uma determinada empresa, desde a base até o atendimento ao cliente. Neste resumo expandido, o mapeamento de processos compõe uma simbologia de identificação de fluxo, onde visualizamos as etapas chaves dentro de um processo logístico. A necessidade de conhecer as etapas deste processo logístico resulta no conceito e na metodologia aplicada. A empresa analisada pertence ramo de eletrodomésticos, situada na cidade de Teófilo Otoni - MG. Foram abordados conceitos teóricos e descritivos para contribuírem na identificação das etapas funcionais a partir da elaboração de um fluxograma para os setores críticos das etapas que compõe a venda de seus produtos. A conclusão deste projeto irá gerar informações que contribuirão com as propostas na melhoria da qualidade e no serviço de atendimento ao cliente.São Cristóvão, S