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Enhancing production monitoring: A back allocation methodology to estimate well flow rates and assist well test scheduling

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Petroleum Research 2024年第3期9卷 369-379页

作者： G.S.Chaves V.J.M.Ferreira Filho universidade federal do Rio de Janeiro Brazil

Production flow rates are crucial to make operational decisions,monitor,manage,and optimize oil and gas *** rates also have a financial importance to correctly allocate production to fiscal purposes required by regulatory agencies or to allocate production in fields owned by multiple *** its significance,usually only the total field production is measured in real time,which requires an alternative way to estimate wells'*** address these challenges,this work presents a back allocation methodology that leverages real-time instrumentation,simulations,algorithms,and mathe-matical programming modeling to enhance well monitoring and assist in well test *** methodology comprises four modules:simulation,classification,error calculation,and *** modules work together to characterize the flowline,wellbore,and reservoir,verify simulation outputs,minimize errors,and calculate flow rates while honoring the total platform flow *** well status generated through the classification module provides valuable information about the current condition of each well(*** the well is deviating from the latest well test parameters),aiding in decision-making for well testing scheduling and *** effectiveness of the methodology is demonstrated through its application to a representative offshore oil field with 14 producing wells and two years of daily production *** results highlight the robustness of the methodology in properly classifying the wells and obtaining flow rates that honor the total platform flow ***,the methodology supports well test scheduling and provides reliable indicators for well *** uti-lizing real-time data and advanced modeling techniques,this methodology enhances production monitoring and facilitates informed operational decision-making in the oil and gas industry.

关键词： Production estimation Real-time production Production monitoring Back allocation Well test scheduling Flow rate estimation

Proposals of SPT-CPT and DPL-CPT correlations for sandy soils in Brazil

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1152-1158页

作者： Mirella Dalvi dos Santos Kátia Vanessa Bicalho universidade federal do Espírito Santo VitóriaBrazil

Field tests in geotechnical engineering are fundamental for identification of the underground *** standard penetration test(SPT) is the most commonly used geotechnical approach. There has been an increase both in the use and application of the in situ tests: cone penetration test(CPT) and dynamic probing(DP). Several empirical SPT-CPT and dynamic probing light(DPL)-CPT correlations for sandy soils have been discussed in the literature. New SPT-CPT and DPL-CPT correlations for the sandy soils of the city of Vitoria, in the southeast of Brazil, are suggested in this paper. Statistical analyses to evaluate the quality of the data used are performed, and the suggested correlations are validated with several previous published datasets. The paper also provides some insights into SPT-CPT correlations and soil characteristics(i.e. the mean particle size and the fines fraction of the soil).

关键词： Standard penetration test(SPT) Cone penetration test(CPT) Dynamic probing light(DPL) Correlations Sands Statistical evaluations

Hydralazine Hydrochloride:An Alternative Complexometric Reagent for Total Iron Spotometric Determination

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American Journal of Analytical Chemistry 2011年第7期2卷 776-782页

作者： Arlan de Assis Gonsalves Cleonia Roberta Melo Araujo Cristiane Xavier Galhardo Marilia Oliveira Fonseca Goulart Fabiane Caxico de Abreu Colegiado de Ciencias Farmaceuticas Universidade Federal do Vale do Sao FranciscoPetrolinaBrazil Colegiado de Engenharia Agronomica Universidade Federal do Vale do Sao FranciscoPetrolinaBrazil Instituto de Quimica e Biotecnologia Universidade Federal de AlagoasMaceioBrazil

An alternative spectrophotometric method has been developed for total iron determination using flow injection analysis (FIA). The procedure is based on the coordination reaction between hydralazine and Fe2+ ions, which results in the formation of a purple complex monitored at 538 nm. For determination of total iron, Fe3+ ions were reduced using ascorbic acid. Under optimized conditions, a linear calibration graph (0.1 - 6.0 ?g?ml–1;n = 6) was obtained. The method allows LOD (3? of blank/slope = 0.06 ?g?ml–1) and LOQ (10? of blank/slope = 0.22 ?g?ml–1). The RSD ((s/ ) × 100) for a mixed standard containing 0.60 ?g?ml–1 Fe2+ and Fe3+ was 0.10% (n = 10). Recoveries of spiked samples were 94.3% - 106.0%. The analytical frequency was 60 h–1. The effect of possible interferences has been studied. The procedure was successfully applied for analysis of environmental samples. The real samples results were comparable with those obtained by the official method considering a paired t-test and 95% of confidence level.

关键词： Hydralazine Total Iron Determination Spectrophotometry Flow Injection Analysis

Dewetting in associating lattice gas model confined by hydrophobic walls

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Science China(Physics,Mechanics & Astronomy) 2019年第10期62卷 60-67页

作者： Tassylla OFonseca Marcia M.Szortyka Patricia Temes Cristina Gavazzoni Alan Bde Oliveira Marcia CBarbosa Instituto de Fsica Universidade Federal do Rio Grande do SulPorto Alegre 91501-970Brasil universidade federal de Santa Catarina Rua Pedro Joao PereiraMato Alto 88900-000Brasil Instituto federal Catarinense Sao Bento do Sul 89283-064Brasil Instituto de Quimica Universidade Estadual de CampinasCampinas 13083-970Brasil Departamento de Fisica Universidade Federal de Ouro PretoOuro Preto 35400-000Brasil

The phase behavior of a two dimensional fluid confined within hydrophobic walls is obtained by Monte Carlo *** fluid is described by the associating lattice gas model which reproduces the density and diffusion anomalous behavior of *** confined fluid exhibits a liquid-liquid critical temperature which decreases with the decrease of the distance between the confining *** contact with the wall a dewetting is *** thickness of this interfacial layer is independent of the distance between the two *** for very small distances between the two walls no total depletion is observed and consequently no drying transition is present.

关键词： water lattice confined

Ophthalmic manifestations in patients with inflammatory bowel disease: a review

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World Journal of Gastroenterology 2017年第32期23卷 5836-5848页

作者： Leandro Lopes Troncoso Ana Luiza Biancardi Haroldo Vieira de Moraes Jr Cyrla Zaltman Department of Ophthalmology Universidade Federal do Rio de Janeiro Department of Internal Medicine Gastroenterology DivisionUniversidade Federal do Rio de Janeiro

Clinical manifestations of inflammatory bowel disease(IBD) are not locally restricted to the gastrointestinal tract, and a significant portion of patients have involvement of other organs and systems. The visual system is one of the most frequently affected, mainly by inflammatory disorders such as episcleritis, uveitis and scleritis. A critical review of available literature concerning ocular involvement in IBD, as it appears in Pub Med, was performed. Episcleritis, the most common ocular extraintestinal manifestation(EIM), seems to be more associated with IBD activity when compared with other ocular EIMs. In IBD patients, anterior uveitis has an insidious onset, it is longstanding and bilateral, and not related to the intestinal disease activity. Systemic steroids or immunosuppressants may be necessary in severe ocular inflammation cases, and control of the underlying bowel disease is important to prevent recurrence. Our review revealed that ocular involvement is more prevalent in Crohn's disease than ulcerative colitis, in active IBD, mainly in the presence of other EIMs. The ophthalmic symptoms in IBD are mainly nonspecific and their relevance may not be recognized by the clinician; most ophthalmic manifestations are treatable, and resolve without sequel upon prompt treatment. A collaborative clinical care team for management of IBD that includes ophthalmologists is central for improvement of quality care for these patients, and it is also cost-effective.

关键词： Inflammatory bowel disease Crohn's disease Ulcerative colitis Ocular complications Eye manifestations

Antioxidant properties of glutamine and its role in VEGF-Akt pathways in portal hypertension gastropathy

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World Journal of Gastroenterology 2013年第28期19卷 4464-4474页

作者： Camila Marques Francielli Licks Ingrid Zattoni Beatriz Borges Luiz Eduardo Rizzo de Souza Claudio Augusto Marroni Norma Possa Marroni universidade federal do Rio Grande do Sul-PPG Fisiologia Porto Alegre 90000100 Brazil universidade federal do Paraná Curitiba 81531900 Brazil Departamento de Medicina Interna-Gastroenterologia-Universidade Federal de Ciências da Saúde de Porto Alegre Porto Alegre 90000100 Brazil universidade federal do Rio Grande do Sul-PPG Fisiologia Universidade Luterana do Brasil Porto Alegre 90000100 Brazil

AIM: To investigate the effects of glutamine on oxidative/nitrosative stress and the vascular endothelial growth factor (VEGF)-Akt-endothelial nitric oxide synthase (eNOS) signaling pathway in an experimental model of portal hypertension induced by partial portal vein ligation (PPVL). METHODS: Portal hypertension was induced by PPVL. The PPVL model consists of a partial obstruction of the portal vein, performed using a 20 G blunt needle as a guide, which is gently removed after the procedure. PPVL model was performed for 14 d beginning treatment with glutamine on the seventh day. On the fifteenth day, the mesenteric vein pressure was checked and the stomach was removed to test immunoreactivity and oxidative stress markers. We evaluated the expression and the immunoreactivity of proteins involved in the VEGF-Akt-eNOS pathway by Western blotting and immunohistochemical analysis. Oxidative stress was measured by quantification of the cytosolic concentration of thiobarbituric acid reactive substances (TBARS) as well as the levels of total glutathione (GSH), superoxide dismutase (SOD) activity, nitric oxide (NO) production and nitrotyrosine immunoreactivity. RESULTS: All data are presented as the mean ± SE. The production of TBARS and NO was significantly increased in PPVL animals. A reduction of SOD activity was detected in PPVL + G group. In the immunohistochemical analyses of nitrotyrosine, Akt and eNOS, the PPVL group exhibited significant increases, whereas decreases were observed in the PPVL + G group, but no difference in VEGF was detected between these groups. Western blotting analysis detected increased expression of phosphatidylinositol-3-kinase (PI3K), P-Akt and eNOS in the PPVL group compared with the PPVL + G group, which was not observed for the expression of VEGF when comparing these groups. Glutamine administration markedly alleviated oxidative/nitrosative stress, normalized SOD activity, increased levels of total GSH and blocked NO overproduction as well

关键词： Partial portal vein ligation Oxidative stress Glutamine Portal hypertension Rats

Characterization of yttria-stabilized zirconia films deposited by dip-coating on La_(0.7)Sr_(0.3)MnO_(3) substrate:Influence of synthesis parameters

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Journal of Advanced Ceramics 2013年第1期2卷 55-62页

作者： Jacqueline C.MARRERO Nielson F.P.RIBEIRO Célia F.MALFATTI Mariana M.V.M.SOUZA Escola de Química-universidade federal do Rio de Janeiro(UFRJ) Centro de TecnologiaBloco Esala 206Ilha do FundãoCEP 21941-909Rio de JaneiroRJBrazil Departamento de Metalurgia Universidade Federal do Rio Grande do Sul(UFRGS)Campus do ValeSetor 4Prédio 75Sala 234CEP 91501-970Porto AlegreRSBrazil

Yttria-stabilized zirconia(YSZ,ZrO_(2)-8%Y2O_(3))films were deposited onto lanthanum strontium manganite(LSM,La_(0.7)Sr_(0.3)MnO_(3))substrates using dip-coating process aiming for the application in solid oxide fuel cells(SOFCs).YSZ precursor was prepared by sol-gel method;three values of the organic/inorganic concentration ratio(1,3 and 5)were utilized and the sol viscosity was adjusted(60 mPa·s and 100 mPa·s)before deposition on the *** influence of these synthesis parameters on the structure and morphology of the deposited films was examined by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The films showed characteristic peaks of LSM,YSZ(with cubic structure)and secondary phases of SrZrO_(3) and La_(2)O_(3).Depending on the synthesis conditions,crack-free,homogeneous and well adhered films were obtained,with thickness of 11-24μm.

关键词： YSZ films LSM sol-gel dip-coating

On the Complexity of Expansive Measures

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Acta Mathematica Sinica,English Series 2015年第9期31卷 1501-1507页

作者： C.A.MORALES Instituto de Matem'atica Universidade Federal do Rio de Janeiro

We prove that the existence of positively expansive measures for continuous maps on compact metric spaces implies the existence of e 〉 0 and a sequence of （m, e）-separated sets whose cardinalities go to infinite as m →∞. We then prove that maps exhibiting such a constant e and the positively expansive maps share some properties.

关键词： Positively expansive measure complexity compact metric space

U-Pb provenance fingerprints of metavolcanic-sedimentary successions of the Mineiro belt:Proxies for the continuity of plate tectonics through the Paleoproterozoic

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Geoscience Frontiers 2022年第5期13卷 309-335页

作者： W.Teixeira C.A.Ávila I.A.Dussin E.Bongiolo Instituto de Geociências Universidade de São PauloBrazil Museu Nacional Universidade Federal do Rio de JaneiroBrazil Faculdade de Geologia Universidade do Estado do Rio de JaneiroBrazil Programa de Pós-graduação em Geociências Instituto de GeociênciasUniversidade Federal do Rio Grande do SulBrazil

We document new U-Pb detrital zircon LA-MC-ICP-MS data for seven metavolcanic-sedimentary successions and metasedimentary sequences and reassess additional dates of five siliciclastic samples toward their tectonic significance in the context of the Mineiro belt,Southern São francisco *** belt represents a crustal segment of the 2.47–2.00 Ga Minas Orogen,classically known by its Siderian and Rhyacian juvenile rocks with important implications in the Earth’s *** new and compiled detrital provenance constraints unravel the long-lived magmatic and sedimentary history of the studied basins,lasting ca.230–220 *** maximum depositional dates around 2.1 Ga reflect the renewed sediment budget with the subsequent metamorphic episode ca.2.0 *** of the unmixed relative probability diagrams are consistent with sourcing from the Siderian and Rhyacian arcs of the Mineiro belt,determining a detrital provenance change in time and space for the precursor *** potential sources could be the youngest rocks of the Mantiqueira and Juiz de Fora terranes that constitute the other segments of the Minas Orogen,given the age *** overall detrital fingerprints determine the study basins resumed mainly in Rhyacian fore-arc and/or back-arc settings,i.e.,akin to a subductionrelated system that evolved to a collisional(foreland)*** samples show fingerprints of primary extensional settings,determined by major Archean detrital populations sourced from areas outside the Mineiro belt beside the Paleoproterozoic *** working model considers the collage between the Mineiro belt and the ancient foreland around 2.10 Ga and eventual interaction with other crustal segments of the Minas Orogen,generating the ca.2.0 Ga metamorphism over the metasedimentary *** more complete isotopic repository in detrital and igneous zircon grains for the studied supracrustal successions and the associated rocks allows new insights into the Rhyacian–Oro

关键词： Paleoproterozoic São francisco Craton Detrital zircon geochronology Metavolcanic-sedimentary basin