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The impact of heterogeneity and pore network characteristics on single and multi-phase fluid propagation in complex porous media:An X-ray computed tomography study

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Petroleum Science 2024年第3期21卷 1719-1738页

作者： Shohreh Iraji Tales Rodrigues de almeida Eddy Ruidiaz Munoz Mateus Basso Alexandre Campane Vidal department of Mechanical Engineering(FEM) State University of Campinas(UNICAMP)CampinasSP13083-860Brazil department of Geology and Natural Resources Geosciences Institute(IG)State University of Campinas(UNICAMP)CampinasSP.13083-855.Brazil LRAP/COPPE/COPPETEC/UFRJ Rua Moniz Aragao 360Bloco 4 Cidade UniversitariaRio de Janeiro21941-594Brazil Center of Energy and Petroleum Studies(CEPETRO) State University of Campinas(UNICAMP)CampinasSP13083-896Brazil

This study investigates the impact of pore network characteristics on fluid flow through complex and heterogeneous porous media,providing insights into the factors affecting fluid propagation in such ***,high-resolution or micro X-ray computed tomography(CT)imaging techniques were utilized to examine outcrop stromatolite samples of the Lagoa Salgada,considered flow analogous to the Brazilian Pre-salt carbonate *** petrophysical results comprised two distinct stromatolite depositional facies,the columnar and the fine-grained *** generating pore network model(PNM),the study quantified the relationship between key features of the porous system,including pore and throat radius,throat length,coordination number,shape factor,and pore *** study found that the less dense pore network of the columnar sample is typically characterized by larger pores and wider and longer throats but with a weaker connection of throats to *** facies exhibited less variability in the radius of the pores and throats in comparison to throat ***,a series of core flooding experiments coupled with medical CT scanning was designed and conducted in the plug samples to assess flow propagation and saturation *** study revealed that the heterogeneity and presence of disconnected or dead-end pores significantly impacted the flow patterns and ***-phase flow patterns and oil saturation distribution reveal a preferential and heterogeneous displacement that mainly swept displaced fluid in some regions of plugs and bypassed it in *** relation between saturation profiles,porosity profiles,and the number of fluid flow patterns for the samples was *** for the columnar plug sample was the enhancement in recovery factor after shifting to lower salinity water injection(SB)observed.

关键词： Pore network model Heterogeneous porous media Flow patterns dead-end pores

Simulated rainfall in Brazil:An alternative for assesment of soil surface processes and an opportunity for technological development

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International Soil and Water Conservation Research 2024年第1期12卷 29-42页

作者： Camila Calazans da Silva Luz Wilk Sampaio de almeida Adilson Pacheco de Souza Nivaldo Schultz Jamil Alexandre Ayach Anache Daniel Fonseca de Carvalho Postgraduate Program in Agronomy-Soil Sciences Federal Rural University of Rio de JaneiroSeropédicaRJBrazil Agronomy department Federal Institute of EducationScience and Technology of RondôniaAriquemesROBrazil Federal University of Mato Grosso SinopMTBrazil Federal Rural University of Rio de Janeiro SeropédicaRJBrazil Federal University of Mato Grosso do Sul Campo GrandeMSBrazil

Rainfall simulators(RS)have been used,above all,to evaluate hydrological processes related to soil water infiltration,surface runoff and soil *** allow repeatability of rain application with different precipitation intensities in field and/or laboratory conditions and should produce events with physical characteristics similar to natural *** this manuscript,we carried out a bibliometric and scientometric analysis of studies with simulated rainfall in Brazil to assess the temporal evolution of publications,the main topics addressed and the degree of technological development of the *** searched for the terms“rainfall simulator”OR“simulated rainfall”AND“Brazil”in the Scopus,Web of Science,SciELO and Google Scholar *** found 143 articles published in the last 37 years(1985-2022).Our findings indicate that the main research areas covered in papers are soil erosion(57.34%),soil water infiltration(24.47%),nutrient losses(9.8%)and RS development and calibration/assessment(8.39%).In recent years,the number of published papers in international high-impact factor journals has *** of the papers(49.65%)refer to studies carried out by institutions located in the south and southeast regions of ***,there is a large gap of studies on simulated rainfall in other regions of Brazil,where important biomes such as the Cerrado,Amazon,Caatinga,and their transitions are *** study informs research priorities on soil erosion under simulated rainfall and provides a bibliographic database that can assist in more detailed future analyses.

关键词： Rainfall simulator Soil and water losses Soil water infiltration Bibliometrics Scientific review

ZnO/CeO_(2)/carbon xerogel composites with direct Z-scheme heterojunctions:Enhancing photocatalytic remediation of 4-chlorophenol under visible light

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Journal of Rare Earths 2024年第2期42卷 314-322,I0003页

作者： Nicolas Perciani de Moraes Maite Birkett de Campos Sanmartin Robson da Silva Rocha Abner de Siervo Marcos roberto de Vasconcelos Lanza D.Amaranatha Reddy Lianqing Yu Liana Alvares Rodrigues Escola de Engenharia de Lorena-EEL/USP Estrada Municipal do Campinho S/NCEP 12602-810LorenaSao PauloBrazil Institute of Physics"Gleb Wataghin" Applied Physics DepartmentState University of Campinas13083-859CampinasSPBrazi Instituto de Quimica de Sao Carlos Universidade de Sao PauloAv.Trab.Sao Carlense400-Parque Arnold SchimidtSao CarlosSP13566-590Spain department of Sciences Indian Institute of Information Technology Design and ManufacturingKurnoolAndhra Pradesh518007India School of Materials Science and Engineering China University of PetroleumQingdao266580China

This paper aims to create visible light driven ternary photocatalysts using zinc oxide(ZnO),cerium(IV)oxide(CeO_(2)),and carbon xerogel(CX) as constituent *** use of CeO_(2) is based on the creation of direct-Z-scheme heterojunctions with the ZnO and the consequent diminishing of charge recombination,whereas the carbon xerogel inclusion is predicted to minimize bandgap energy,decrease electro n-hole reco mbination,and boost specific surface *** re,the choice of the black-wattle tannin as a carbonaceous precursor was targeted at the development of an environmentally friendly and affordable *** existence of the hexagonal phase of zinc oxide and cubic structure of the cerium(IV) oxide in the ternary material was confirmed by X-ray diffractometry and X-ray photoelectron spectroscopy,with the latter also suggesting chemical bonding between the ZnO and the CX due to the creation of zinc oxycarbide *** inclusion of the carbon xerogel provokes a significant modification in the morphology of the ternary material,resulting in an increased surface area and smaller particle *** CX/ZnO-CeO_(2) ternary composite obtains the highest photocatalytic efficiency among all the materials studied,degrading 100% of 4-chlorophenol under simulated sunlight and 68% under visible radiation,after 5 *** increased photocatalytic activity can be attributed to the formation of direct Z-scheme heterojunctions between the semiconductors,higher visible light response,and higher specific surface area,as evidenced by the results obtained by active radical scavenging,chronoamperometry,diffuse reflectance spectroscopy,and N_(2) adsorption-desorption isotherms.

关键词： Zinc oxide Cerium(Ⅳ)oxide Carbon xerogel Photocatalysis Direct Z-scheme heterojunction 4-Chlorophenol Rare earths

Accuracy of Rapid Prototyping Biomodels Plotted by Three Dimensional Printing Technique:Ex Vivo Study

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Advances in Computed Tomography 2013年第2期2卷 41-45页

作者： Lucio Costa Safira Luana Costa Bastos Valter Estevao Beal roberto almeida de azevedo Carlos Eduardo Francischone Viviane almeida Sarmento Research Center Sao Leopoldo Mandic CampinasBrazil School of dentistry Federal University of BahiaSalvadorBrazil SENAI-CIMATEC SalvadorBrazil School of dentistry of Bauru University of Sao PauloBauruBrazil School of dentistry State University of Feira de SantanaFeira de SantanaBrazil

The rapid prototyping biomodels manufacturing is a recent technology with great importance in oral and maxillofacial surgery. It provides a better surgical planning, decrease of anesthesia time and great functional and esthetic results. The aim of this experimental study was to evaluate the accuracy of rapid prototyping biomodels built by three-dimensional printing (3DP) technique, since this is one of the least expensive methods available. Linear measurements of standardized bone defects and anatomic distances were compared using a digital caliper of high precision in nine dry mandibles (gold standard) and their respective biomodels. The Bland-Altman test was used for statistical analysis (5% level of significance). The results showed strong concordance between the dry mandibles and their respective biomodels, with discrepancies smaller than 2 mmin most cases (97.4%). We can conclude that the biomodels built by 3DP technique can be used for surgical planning in dentistry.

关键词： Rapid Prototyping Models Computed Tomography Mandible

Motivations for and barriers to innovation in non-profit organizations: The case of nursing homes in Northern Portugal

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International Journal of Innovation Studies 2024年第1期8卷 25-44页

作者： Ana Rita Gonçalves Lopes Aldina Isabel de azevedo Correia Alexandra Maria da Silva Braga Center for Research and Innovation in Business Sciences and Information Systems School of Management and TechnologyPolitecnico do PortoRua do Curral-Margaride4610-156 FelgueirasPortugal

To contribute to the empirical literature on innovation in non-profit organizations,this study examines innovation in Private Social Solidarity Institutions with social responses for the elderly in Northern *** enriches the literature by clarifying the concept of innovation applied to non-profit organizations,which represents a perspective different from the business ***,it is important to support the innovation decisionmaking process in similar non-profit *** this study,the population was surveyed through questionnaires based on the PUBLIN research project,which has already been applied in different countries,and the targets were employees of organizations with social responses for the *** sample is small,with 28 respondent institutions and 51 employees,but it is representative,as it includes institutions from all districts in Northern *** study employed a quantitative approach,particularly factor analysis,multiple linear regression,and correlation analyses,using scales already applied in other dimensions of the social sector,to understand the effect of each innovation dimension/determinant on creativity and innovation in nonprofit *** results show that in these organizations with social responses for the elderly,learning orientation,risk-taking,and job satisfaction have a positive impact on innovation.

关键词： determinants of innovation non-profit organizations social responses for the elderly Northern Portugal

Investigation of pore geometry influence on fluid flow in heterogeneous porous media:A pore-scale study

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Energy Geoscience 2024年第1期5卷 72-88页

作者： Ramin Soltanmohammadi Shohreh Iraji Tales Rodrigues de almeida Mateus Basso Eddy Ruidiaz Munoz Alexandre Campane Vidal Ingram School of Engineering Texas State UniversitySan MarcosTX78666USA department of Mechanical Engineering(FEM) State University of Campinas(UNICAMP)CampinasSP13083-855Brazil department of Geology and Natural Resources Geosciences Institute(IG)State University of Campinas(UNICAMP)CampinasSP13083-855Brazil Center of Energy and Petroleum Study(CEPETRO) State University of Campinas(UNICAMP)CampinasSP13083-855Brazil

Brazilian pre-salt reservoirs are renowned for their intricate pore networks and vuggy nature,posing significant challenges in modeling and simulating fluid flow within these carbonate *** possessing excellent petrophysical properties,such as high porosity and permeability,these reservoirs typically exhibit a notably low recovery factor,sometimes falling below 10%.Previous research has indicated that various enhanced oil recovery(EOR)methods,such as water alternating gas(WAG),can substantially augment the recovery factor in pre-salt reservoirs,resulting in improvements of up to 20%.Nevertheless,the fluid flow mechanism within Brazilian carbonate reservoirs,characterized by complex pore geometry,remains *** study examines the behavior of fluid flow in a similar heterogeneous porous material,utilizing a plug sample obtained from a vugular segment of a Brazilian stromatolite outcrop,known to share analogies with certain pre-salt *** conducted single-phase and multi-phase core flooding experiments,complemented by medical-CT scanning,to generate flow streamlines and evaluate the efficiency of water ***,micro-CT scanning of the core sample was performed,and two cross-sections from horizontal and vertical plates were *** cross-sections were then employed as geometries in a numerical simulator,enabling us to investigate the impact of pore geometry on fluid *** of the pore-scale modeling and experimental data unveiled that the presence of dead-end pores and vugs results in a significant portion of the fluid remaining stagnant within these ***,the injected fluid exhibits channeling-like behavior,leading to rapid breakthrough and low areal swept ***,the numerical simulation results demonstrated that,irrespective of the size of the dead-end regions,the pressure variation within the dead-end vugs and pores is *** the stromatolite's favorable petrophysica

关键词： Pore-scale modeling Pore geometry Flow streamlines Computational modeling Digital rock analysis

Current Topics in Acute Abdomen: Causes, Diagnostics, and Emerging Therapies

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Journal of Biosciences and Medicines 2024年第5期12卷 171-177页

作者： Lucas de Oliveira Varca Maria Carolina de almeida Santo department of Medicine Universidade do Oeste Paulista Guaruj&#225 Brazil

Acute abdomen is a serious clinical condition that requires immediate attention due to its association with intense pain and rapid progression. This article reviews important aspects of the causes, diagnostics, and treatments of acute abdomen. The research highlights the diversity of etiologies, ranging from the most common, such as acute appendicitis, to the less frequent, such as intestinal perforations by foreign bodies. Complex diagnostic methods, including clinical examinations and imaging such as computed tomography, are essential to guide accurate diagnosis, given the overlap of symptoms among different conditions. Therapeutic approaches range from conservative treatments with clinical observation and antibiotic therapy to urgent surgical interventions, such as appendectomy and cholecystectomy. Laparoscopy stands out as a promising approach, offering advantages in terms of recovery and post-operative morbidity. However, the impact of the COVID-19 pandemic has brought additional challenges to the diagnosis and treatment of acute abdomen, with delays and difficulties in accessing healthcare. This review underscores the importance of a multidisciplinary approach and constant updates among healthcare professionals in addressing acute abdomen, aiming for accurate diagnoses and appropriate therapeutic interventions to improve clinical outcomes and reduce morbidity and mortality associated with this complex clinical condition.

关键词： Component Formatting Style Styling Insert

A high-order target phase approach for the station-keeping of periodic orbits

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Astrodynamics 2024年第1期8卷 61-75页

作者： Xiaoyu Fu Nicola Baresi roberto Armellin Surrey Space Centre University of SurreyGuildfordGU27XHUK Te PūnahaĀtea-Auckland Space Institute University of AucklandAuckland1010New Zealand

A novel high-order target phase approach(TPhA)for the station-keeping of periodic orbits is proposed in this *** key elements of the TPhA method,the phase-angle Poincare map and high-order maneuver map,are constructed using differential algebra(DA)techniques to determine station-keeping epochs and calculate correction maneuvers.A stochastic optimization framework tailored for the TPhA-based station-keeping process is leveraged to search for fuel-optimal and error-robust TPhA ***-satellite orbits(QSOs)around Phobos are investigated to demonstrate the efficacy of TPhA in mutli-fidelity dynamical *** Carlo simulations demonstrated that the baseline QSO of JAXA’s Martian Moons eXploration(MMX)mission could be maintained with a monthly maneuver budget of approximately 1 m/s.

关键词： target phase approach(TPhA) station-keeping Poincarémap differential algebra(DA) quasi-satellite orbit(QSO)

Brent *** Texas Intermediate in the US petro derivatives price formation

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Petroleum Science 2024年第1期21卷 729-739页

作者： Alejandro almeida Antonio A.Golpe Juan Manuel Martín-Alvarez Jose Carlos Vides Universidad Internacional de La Rioja Department of Quantitative Methods for Economics and BusinessLa RiojaSpain University of Huelva Department of Economics and Centro de Estudios Avanzados en FisicaMatematicas y Computacion and ICEIHuelvaSpain Complutense University of Madrid Department of Applied and Structural Economics and History and ICEIMadridSpain

In this paper,we apply the spatial panel model to explore the relationship between the dynamic of two types of crude oil prices(WTI and Brent crude oil)and their refined products over *** the turbulent months of 2011,when Cushing Oklahoma had reached capacity and the crude oil export ban removal in 2015 as breakpoints,we apply this method both in the full sample and the three resultant ***,results suggest our results show that both WTI and Brent display very similar behaviour with the refined ***,when attending to each regime,results derived from the first and third regimes are quite similar to the full sample ***,during the second regime,Brent crude oil became the benchmark in the petrol market,and it influenced the distillate ***,our model can let us determine the price-setters and price-followers in the price formation mechanism through refined *** results possess important considerations to policymakers and the market participants and the price formation.

关键词： Crude oil prices Spatial panel model Refined products Price formation