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Thermal Hydraulic Analysis Improvement for the IEA-R1 Research Reactor and Fuel Assembly Design Modification

World Journal of Nuclear Science and Technology 2018年第2期8卷 54-69页

作者： Pedro Ernesto Umbehaun Walmir Maximo Torres josé antonio batista souza Mitsuo Yamaguchi antonio Teixeira e Silva Roberto Navarro de Mesquita Nikolas Lymberis Scuro Delvonei Alves de Andrade Nuclear and Energy Research Institute (Instituto de Pesquisas Energéticas e Nucleares) S&auml o Paulo Brazil

This paper presents the sequence of activities to improve the thermal hydraulic analysis of the IEA-R1 research reactor to operate in safe conditions after power upgrade from 2 to 5 MW and core size reduction from 30 to 24 fuel assemblies. A realistic analysis needs the knowledge of the actual operation conditions (heat flow, flow rates) beyond the geometric data and the uncertainties associated with manufacturing and measures. A dummy fuel assembly was designed and constructed to measure the actual flow rate through the core fuel assemblies and its pressure drop. First results showed that the flow distribution over the core is nearly uniform. Nevertheless, the values are below than the calculated ones and the core bypass flow rate is greater than those estimated previously. Based on this, several activities were performed to identify and reduce the bypass flow, such as reduction of the flow rate through the sample irradiators, closing some unnecessary secondary holes on the matrix plate, improvement in the primary flow rate system and better fit of the core components on the matrix plate. A sub-aquatic visual system was used as an important tool to detect some bypass flow path. After these modifications, the fuel assemblies flow rate increased about 13%. Additional tests using the dummy fuel assembly were carried out to measure the internal flow distribution among the rectangular channels. The results showed that the flow rate through the outer channels is 10% - 15% lower than the internal ones. The flow rate in the channel formed between two adjacent fuel assemblies is an estimated parameter and it is difficult to measure because this is an open channel. A new thermal hydraulic analysis of the outermost plates of the fuel assemblies takes into account all this information. Then, a fuel design modification was proposed with the reduction of 50% in the uranium quantity in the outermost fuel plates. In order to avoid the oxidation of the outermost plates by high temperature, low flow rate, a reduction of 50% in th

关键词： Nuclear Research Reactor Uranium Reduction Thermal Hydraulic Analysis Flow Measurement Dummy Fuel Assembly

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Entropy model to assess sediment resuspension probability and trap efficiency of small dams

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International Journal of Sediment Research 2022年第5期37卷 675-686页

作者： Francisco Jairo Soares Pereira antonio Viana da Silva Filho josé Wellington batista Lopes josé Carlos de Araújo Department of Agricultural Engineering Federal University of Ceará Campus Do Pici Rural Federal University of Pernambuco Federal University of Piauí

In the Brazilian drylands, there are tens of thousands of small dams. Despite their paramount importance to the rural population, they are rarely monitored. Water demand increases with time while, simultaneously, siltation reduces reservoir water capacity and availability. Reservoir siltation models are, therefore, mandatory to manage the numerous ungauged small dams in these drylands.The objective of the current study is to improve sediment trap efficiency(TE) modeling by including resuspension as a key probabilistic process. The Shannon entropy was used to estimate the sediment resuspension probability, which was merged with the Camp model and generated the RETSED entropy model. To validate the RETSED model, an experimental check dam(ECD, 300 m3), located in the Gilbu es desertification site, Brazil, was monitored hourly during one hydrological year(July 2018-July 2019). Measurements show that the annual volumetric decline of the check dam was 12%; and that the average trap efficiency equaled 86%. Only 9.5% of the hourly sediment concentration outflow exceeded the average plus one standard deviation, showing that the reservoir is well mixed; a fact which highlights the relevance of the resuspension process. Three empirical models failed to mimic the experimental results: Churchill(TE = 99%), Brune(TE = 75%), and Maryland(TE = 94%). According to the RETSED entropy model, the resuspension probability during the experiment was 10%and TE = 81%, a value only 6% below the measured one. The Camp model simulated TE = 89%, only 3%higher than the measured value, but confirmed the Camp model’s tendency to overestimate TE due to a disregard of resuspension. The deterministic model showed low sensitivity concerning the hydrodynamic effects, whereas the entropy formulation proved to be more consistent with physical behavior: the resuspension probability clearly increased and trap efficiency decreased with rising reservoir discharge.

关键词： Erosion Check dam Sedimentation Ungauged basins Camp model

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A numerical assessment of two geometries for reducing elbow erosion

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Particuology 2020年第2期18卷 117-133页

作者： Carlos antonio Ribeiro Duarte Francisco joséde souza Diego Nei Venturi Martin Sommerfeld Department of Engineering Federal University of Goiás-Regional Catal(a)oAv.Dr.Lamartine Pinto de Avelar1120Catal(a)oGoiásBrazil School of Mechanical Engineering Federal University of Uberl(a)ndiaAv.Joāo Naves de(A)vila2121 Bloco 5PUberl(a)ndiaMinas GeraisBrazil Multiphase Flow Systems(MPS) Otto-von-Guericke-University MagdeburgZeppelinstraβe 1D-06130 Halle(Saale)Germany

Elbows in pneumatic conveying systems are normally prone to the erosive effects of conveyed particles.There are a number of solutions available to reduce such damage.A widely used geometric alternative for replacing the 90°elbow and reducing erosive wear is the plugged tee.Another option,although less commonly used,is the vortex-chamber elbow.In both cases,the effective reduction in erosion brought about is unclear,as it strongly depends on the operating conditions.The present study assesses relative erosion among the plugged tee,vortex-chamber elbow,and standard elbow for a dilute gas-solid multiphase flow.A numerical model is employed to predict the penetration ratio and validated using experimental data for the plugged tee.Simulations are run for the standard and vortex-chamber elbows and plugged tee under the same conditions to compare the mechanics involved and the relative erosion reduction.The analysis uses variables relating to particle-wall interactions(impact angle,impact velocity,impact frequency)to illustrate the nature of the erosive process in each pipe fitting.In general,the geometric configurations of both the plugged tee and vortex-chamber elbow promote changes in particle dynamics that reduce the rate of erosion.On the basis of the relative erosion of the standard elbow,the plugged tee proves to be an interesting option in cases of a low mass loading,while the vortex-chamber elbow demonstrates its erosion reduction potential for higher mass loading conditions.Furthermore,the advantages and disadvantages of each fitting are highlighted.

关键词： Relative erosion Plugged tee Erosion reduction Pipe fitting Computational fluid dynamics

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Preservation of platelet function in patients with cirrhosis and thrombocytopenia undergoing esophageal variceal ligation

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Hepatobiliary & Pancreatic Diseases International 2020年第6期19卷 555-560页

作者： Evandro de Oliveira souza Elbio antonio D’Amico Tania Rubia Flores da Rocha Caroline Marcondes Ferreira Juliana Medeiros batista Luiz Augusto CarneiroD’Albuquerque Flair jose Carrilho Alberto Queiroz Farias Division of Gastroenterology and Hepatology University of Sao Paulo School of MedicineAv.Dr.Eneas Carvalho de Aguiar2559th flooroffice 9159Sao PauloSP 05403-000Brazil Hemostasis Laboratory Hematology ServiceUniversity of Sao Paulo School of MedicineAv.Dr.Eneas Carvalho de Aguiar2552nd floorSao PauloSP 05403-000Brazil

Background:Thrombocytopenia is a possible risk factor for bleeding after band ligation of esophageal varices.However,elevated von Willebrand factor(VWF)in cirrhosis improves platelet function and could decrease this risk.Our objective was to assess platelet function in patients with cirrhosis undergoing esophageal variceal ligation(EVL).Methods:The assessment consisted of platelet count,antigen and activity of VWF and VWF-cleaving protease ADAMTS-13 activity,and a platelet adhesion and aggregation test simulating vascular flow in vivo(Impact-RR)prior to EVL.Results:Totally 111 patients were divided into three groups according to platelet count:(1)100×109/L(n=26,23.4%).No statistically significant difference was found in the aggregate size of platelets[group 1:41.0(31.8–67.3)μm 2;group 2:47.0(33.8–71.3)μm 2;and group 3:47.0(34.0–66.0)μm 2;P=0.60]and no significant correlation was found between aggregate size and platelet count(Spearman r=0.07;P=0.47).Surface coverage was 4.1%(2.8%–6.7%),8.5%(4.0%–10.0%),and 9.0%(7.1%–12.0%)(P<0.001)in groups 1,2 and 3,respectively and correlated with platelet count(Spearman r=0.39;P<0.0001).There was no significant difference between groups in VWF or ADAMTS-13.Post-EVL bleeding occurred in six(5.4%)patients(n=2 in group 1,n=1 in group 2,and n=3 in group 3;P=0.32).Patients with bleeding had higher MELD scores[15.0(11.3–20.3)versus 12.0(10.0–15.0);P=0.025],but no difference was demonstrated for platelet function parameters.Conclusion:Platelet function is preserved even in the presence of thrombocytopenia,including in the patients with post-EVL bleeding.

关键词： Cirrhosis Hemostasis Thrombocytopenia Platelet aggregation Endoscopy Hemorrage

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Extrahepatic right hepatic duct diverticulum: a rare entity

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Hepatobiliary & Pancreatic Diseases International 2010年第2期9卷 213-215页

作者： Eduardo SM Fernandes Raquel L Bernardo Moacir M Fernandes Rogério MC Araújo Renato Sebbe Asterio Monte joséF Coelho antonio AP souza Joaquim Ribeiro Filho Department of General Surgery Section of Hepatobiliary Surgery and TransplantationRio de Janeiro Federal University Department of Digestive Surgery and Gastroenterology Pio XII General Hospital

BACKGROUND:Douglas described choledochal cysts in 1852 and Todani proposed an anatomy-based classification in 1977. The classification is the most extensively used,but does not include some rare variations.We present a case of hepatic duct diverticulum,one of the variations,and discuss its diagnosis and treatment. METHODS:A 57-year-old woman presented with upper abdominal pain and discomfort associated with nausea and vomiting.She was finally diagnosed with cholelithiasis and right hepatic duct diverticulum. RESULT:The patient underwent resection of the hepatic duct diverticulum and cholecystectomy,and was asymptomatic 26 months after surgery. CONCLUSIONS:Hepatic duct diverticulum is a rare form of choledochal cyst,not included in Todani’s classification. Todani’s classification including this and other uncommon variations of choledochal cysts must be reviewed.The best diagnostic imaging methods and treatment for choledochal cysts must be defined.

关键词： choledochal cysts hepatic duct diverticulum Todani's classification intrahepatic diverticulum

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Serum 1,3-beta-D-glucan as a noninvasive test to predict histologic activity in patients with inflammatory bowel disease

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World Journal of Gastroenterology 2021年第9期27卷 866-885页

作者： Katia Farias e Silva Hayandra F Nanini Cynthia Machado Cascabulho Siane L B Rosas Patricia T Santana antonio joséde V Carneiro Elias Anaissie Marcio Nucci Heitor Siffert Pereira de souza Department of Clinical Medicine School of MedicineFederal University of Rio de JaneiroRio de Janeiro 21941-913Brazil Laboratory of Innovations in Therapies Education and BioproductsInstituto Oswaldo CruzRio de Janeiro 21040-360Brazil Clinical Trial and Consulting Services CincinnatiOH 45267United States Internal Medicine D'Or Institute for Research and Education(IDOR)Rio de Janeiro 22281-100Brazil

BACKGROUND 1,3-beta-D-glucan(BG)is a ubiquitous cell wall component of gut microorganisms.We hypothesized that the serum levels of BG could reflect active intestinal inflammation in patients with inflammatory bowel disease.AIM To determine whether the serum BG concentrations correlate with intestinal inflammation.METHODS A prospective observational study was performed in a tertiary referral center,from 2016 to 2019,in which serum BG was determined in 115 patients with Crohn’s disease(CD),51 with ulcerative colitis(UC),and 82 controls using a photometric detection kit.Inflammatory activity was determined by ileocolonoscopy,histopathology,magnetic resonance enterography,and biomarkers,including fecal calprotectin(FC),C-reactive protein,and a panel of cytokines.The ability of BG to detect active vs inactive disease was assessed using the area under the receiver operating characteristic curve.In subgroup analysis,serial BG was used to assess the response to therapeutic interventions.RESULTS The serum BG levels were higher in CD patients than in controls(P=0.0001).The BG levels paralleled the endoscopic activity in CD patients and histologic activity and combined endoscopic and histologic activity in both CD and UC patients.The area under the curve(AUC)in receiver operating characteristic analysis to predict endoscopic activity was 0.694[95%confidence interval(CI):0.60-0.79;P=0.001]in CD,and 0.662(95%CI:0.51-0.81;P=0.066)in UC patients.The AUC in receiver operating characteristic analysis to predict histologic activity was 0.860(95%CI:0.77-0.95;P<0.001)in CD,and 0.786(95%CI:0.57-0.99;P=0.015)in UC patients.The cut-off values of BG for both endoscopic and histologic activity were 60μg/mL in CD,and 40μg/mL in UC patients.Performance analysis showed that the results based on BG of 40 and 60μg/mL were more specific for predicting endoscopic activity(71.8%and 87.2%for CD;and 87.5%and 87.5%for UC,respectively)than FC(53.3%and 66.7%for CD;and 20%and 80%for UC,respectively);and also histologic activity(60.5%and 76.3%for CD;an

关键词： Crohn’s disease Ulcerative colitis Inflammatory bowel disease Beta-glucan Histologic activity Noninvasive test

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Anti-inflammatory intestinal activity of Combretum duarteanum Cambess. in trinitrobenzene sulfonic acid colitis model

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World Journal of Gastroenterology 2017年第8期23卷 1353-1366页

作者： Gedson Rodrigues de Morais Lima Flavia Danniele Frota MachadoLarissa Lucena Périco Felipe Meira de Faria Anderson Luiz-Ferreira Alba Regina Monteiro souza Brito Cláudia Helena Pellizzon Clélia Akiko Hiruma-Lima josean Fechine Tavares joséMaria Barbosa Filho LeOnia Maria batista Departamento de Ciências Farmacêuticas Centro de Ciências da SaúdeLaboratório de Farmacologia do Trato GastrintestinalUniversidade Federal da Paraíba(UFPB)Cidade Universitária Departamento de Fisiologia Instituto de BiociênciasUniversidade Estadual Paulista Departamento de Biologia Estrutural e Funcional Instituto de BiologiaUniversidade Estadual de Campinas(UNICAMP Departamento de Ciencias Biológicas Instituto de BiotecnologiaUniversidade Federal de Goiás Departamento de Morfologia Instituto de BiociênciasUniversidade Estadual Paulista

AIM To evaluate the anti-inflammatory intestinal effect of the ethanolic extract(EtO HE) and hexane phase(HexP) obtained from the leaves of Combretum duarteanum(Cd).METHODS Inflammatory bowel disease was induced using trinitrobenzenesulfonic acid in acute and relapsed ulcerative colitis in rat models. Damage scores, and biochemical, histological and immunohistochemical parameters were evaluated. RESULTS Both Cd-Et OHE and Cd-Hex P caused significant reductions in macroscopic lesion scores and ulcerative l e sionareas. The vegetable samples inhibited myeloperoxidase increase, as well as pro-inflammatory cytokines TNF-α and IL-1β. Anti-inflammatory cytokine IL-10 also increased in animals treated with the tested plant samples. The anti-inflammatory intestinal effect is related to decreased expression of cyclooxygenase-2, proliferating cell nuclear antigen, and an increase in superoxide dismutase. CONCLUSION The data indicate anti-inflammatory intestinal activity. The effects may also involve participation of the antioxidant system and principal cytokines relating to inflammatory bowel disease.

关键词： Combretum duarteanum 药用的植物 Combretaceae 煽动性的肠疾病反煽动性的肠的活动

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“If We Only Knew How You Feel”—A Comparative Study of Automated vs. Manual Classification of Opinions of Customers on Digital Media

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Social Networking 2019年第1期8卷 74-83页

作者： Huoston Rodrigues batista josé Carmino Gomes Junior Marcelo Drudi Miranda Andréa Martiniano Renato josé Sassi Marcos antonio Gaspar Postgraduate Program in Informatics and Knowledge Management Nove de Julho University Sao Paulo SP Brazil

The Web development has drastically changed the human interaction and communication, leading to an exponential growth of data generated by users in various digital media. This mass of data provides opportunities for understanding people’s opinions about products, services, processes, events, political movements, and organizational strategies. In this context, it becomes important for companies to be able to assess customer satisfaction about their products or services. One of the ways to evaluate customer sentiment is the use of Sentiment Analysis, also known as Opinion Mining. This research aims to compare the efficiency of an automatic classifier based on dictionary with the classification by human jurors in a set of comments made by customers in Portuguese language. The data consist of opinions of service users of one of the largest Brazilian online employment agencies. The performance evaluation of the classification models was done using Kappa index and a Confusion Matrix. As the main finding, it is noteworthy that the agreement between the classifier and the human jurors came to moderate, with better performance for the dictionary-based classifier. This result was considered satisfactory, considering that the Sentiment Analysis in Portuguese language is a complex task and demands more research and development.

关键词： Sentiment Analysis Opinion Mining Social Media

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Device Design for SAE 1020 Steel Tool Storage Applied to Automotive Industry

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Management Studies 2019年第6期7卷 588-600页

作者： Marcílio Antunes Leite Filho Rosinei batista Ribeiro Adriano joséSorbile de souza joséWilson de Jesus Silva Wellington de Oliveira University Center Teresa D’ávila-UNIFATEA LorenaBrazil

Wood pallets are the most commonly used resources in tool storage in the press industry,where components are modeled for automotive industry.The aim of this work was to develop AISI 1020 carbon steel metal rack for storing the set of cutting,drilling,and folding tools.The collaborating company is a manufacturer of automotive components for buses,trucks,and pickup trucks.It is located in the municipality of Cruzeiro,S?o Paulo and Metropolitan Sub-region of Vale do Paraíba and Litoral Norte 4.Methodology used in the execution of this project was the microstructural characterization of AISI 1020 by techniques of metallography,hardness,modeling and mechanical simulation,development of metal rack design by technical details in 2D via AutoCad?for prototype,or in 3D by means of virtual modeling Cliever Lab(Pro)?to create a mock-up.In production and operations management the average time of handling of forklifts was analyzed using the timer in the current logistic process in the forklift,crane,tool,and pallet assembly.The result obtained so far by means of development of metal rack was the reduction of environmental liabilities,greater storage safety and reduction in time of tool movement.

关键词： rack design design and material selection product design 3D prototyping

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Numerical Simulation of the Shell-and-Tube Heat Exchanger:Influence of the Lower Flows and the Baffles on a Fluid Dynamics

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Advances in Chemical Engineering and Science 2017年第4期7卷 349-361页

作者： Sebastiao josédos Santos Filho josedite Saraiva de souza antonio Gilson Barbosa de Lima Departament of Mechanical Engineering UNINASSAUCampina GrandeBrazil Departament of Mechanical Engineering Federal University of Campina GrandeCampina GrandeBrazil

This project proposes the numerical reproduction development of the water flow in a shell-and-tube heat exchanger 2:1 according to the CLASS C TEMA standard (for moderate operation conditions, with commercial application). With baffles in aluminum and copper tube for the cold fluid flow, the shell is in acrylic, and with thermal analysis efficiencies with regard to the presence or not of the baffles, that is to analyze the efficiency with only, the tubes and the shell and soon after the analysis with tubes and baffles. Heat exchangers are widely used equipment on an industrial and commercial scale, the application of these equipments on an industrial scale represents innovative processing solutions reflecting the processes efficiency, producing significant savings and lower cost, supporting the business success, and consequently offering opportunities, social responsibility, which are the pillars of sustainability. For the development of this work the methodology was used to calculate effectiveness, following the design parameters and contour conditions, it was analyzed the fluids behavior in the shell and the tube, through computational fluid dynamics (CFD) using the software ANSYS CFX 15.0. The results were compared with Excel generated worksheets calculated using the existing equations and correlations.

关键词： Heat Exchanger CFD Baffles ANSYS CFX

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