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Effects of Andrade and Burgers rheologies on glacial isostatic adjustment modeling in Antarctica

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Geodesy and Geodynamics 2024年第5期15卷 429-440页

作者： alexandre Boughanemi Anthony Mémin UniversitéCôte d'Azur CNRSObservatoire de la Côte d'AzurIRDGéoazur250 rue Albert EinsteinSophia Antipolis 06560 ValbonneFrance

Variations in ice mass deform the Earth and modify its gravity field,a process known as Glacial Isostatic Adjustment(GIA).GIA in Antarctica remains poorly constrained due to the cumulative effect of past and present ice-mass changes,the unknown history of the past ice-mass change,and the uncertainties on the mechanical properties of the *** paper investigates the effect of using Andrade and Burgers viscoelastic rheologies,rather than the commonly used Maxwell rheology,to model GIA-induced deformation in *** Love number and Green's function formalism are used to compute the radial surface displacements and the gravity changes induced by the past and present ice-mass *** consider an Earth model whose elastic properties and radial structure are averaged from the Preliminary Reference Earth Model and two viscosity profiles to account for the recently published results on the present ice-mass *** the three rheological laws affects the temporal response of the Earth differently,leading to smaller discrepancies than those induced by the two viscosity *** differences are the largest between Maxwell and Burgers rheologies during the 100-1000 years following the beginning of the surface-mass *** show that using the Andrade and Burgers rheologies allows the Earth to respond on decennial to centennial time scales,up to 10 m more than *** only the recent ice-mass changes,the deformation rates derived from Burgers and Andrade rheologies are several times larger than those estimated by Maxwell rheology.

关键词： GIA Antarctica Modeling Rheology Displacement Viscosity GNSS

Influence of manufacturing process-induced geometrical defects on the energy absorption capacity of polymer lattice structures

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Defence Technology（防务技术） 2024年第5期35卷 47-59页

作者： alexandre Riot Enrico Panettieri Antonio Cosculluela Marco Montemurro Universite de Bordeaux Arts et Metiers Institute of TechnologyCNRSINRABordeaux INPHESAM UniversiteI2M UMR 5295F-33405 TalenceFrance French Atomic Energy Commission Route des GargailsCedexF-33114Le BarpFrance

Modern additive manufacturing processes enable fabricating architected cellular materials of complex shape,which can be used for different *** them,lattice structures are increasingly used in applications requiring a compromise among lightness and suited mechanical properties,like improved energy absorption capacity and specific stiffness-to-weight and strength-to-weight ratios.A dedicated modeling strategy to assess the energy absorption capacity of lattice structures under uni-axial compression loading is presented in this *** numerical model is developed in a non-linear framework accounting for the strain rate effect on the mechanical responses of the lattice *** geometries,i.e.,cubic body centered cell,octet cell,rhombic-dodecahedron and truncated cuboctahedron 2+,are ***,the influence of the relative density of the representative volume element of each geometry,the strain-rate dependency of the bulk material and of the presence of the manufacturing process-induced geometrical imperfections on the energy absorption capacity of the lattice structure is *** main outcome of this study points out the importance of correctly integrating geometrical imperfections into the modeling strategy when shock absorption applications are aimed for.

关键词： Lattice structures Architected cellular materials Dynamic simulation Energy absorption Geometrical imperfection Additive manufacturing

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

Assimilation of GOES-R Geostationary Lightning Mapper Flash Extent Density Data in GSI 3DVar, EnKF, and Hybrid En3DVar for the Analysis and Short-Term Forecast of a Supercell Storm Case

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Advances in Atmospheric Sciences 2024年第2期41卷 263-277页

作者： Rong KONG Ming XUE Edward R.MANSELL Chengsi LIU alexandre O.FIERRO Center for Analysis and Prediction of Storms Norman Oklahoma 73072U.S.A University of Oklahoma Norman Oklahoma 73072U.S.A NOAA/National Severe Storms Laboratory NormanOklahoma 73072U.S A.4Zentralanstalt für Meteorologie und Geodynamik Department of Forecasting Models-ZAMGVienna 1190Austria

Capabilities to assimilate Geostationary Operational Environmental Satellite “R-series ”(GOES-R) Geostationary Lightning Mapper(GLM) flash extent density(FED) data within the operational Gridpoint Statistical Interpolation ensemble Kalman filter(GSI-EnKF) framework were previously developed and tested with a mesoscale convective system(MCS) case. In this study, such capabilities are further developed to assimilate GOES GLM FED data within the GSI ensemble-variational(EnVar) hybrid data assimilation(DA) framework. The results of assimilating the GLM FED data using 3DVar, and pure En3DVar(PEn3DVar, using 100% ensemble covariance and no static covariance) are compared with those of EnKF/DfEnKF for a supercell storm case. The focus of this study is to validate the correctness and evaluate the performance of the new implementation rather than comparing the performance of FED DA among different DA schemes. Only the results of 3DVar and pEn3DVar are examined and compared with EnKF/DfEnKF. Assimilation of a single FED observation shows that the magnitude and horizontal extent of the analysis increments from PEn3DVar are generally larger than from EnKF, which is mainly caused by using different localization strategies in EnFK/DfEnKF and PEn3DVar as well as the integration limits of the graupel mass in the observation operator. Overall, the forecast performance of PEn3DVar is comparable to EnKF/DfEnKF, suggesting correct implementation.

关键词： GOES-R lightning data assimilation EnKF EnVar

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

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The Knight Of Change

ChinAfrica 2024年第10期16卷 40-41页

作者： CHRISTOPHE alexandre 不详

A Nigerian chess player transforms the lives of children through his *** Onakoya is a Nigerian chess player and social activist whose influence extends far beyond the 64 squares of the *** the founder of the Chess in Slums initiative,he uses chess as a powerful tool to educate,motivate,and transform the lives of young people in Nigeria’s underprivileged *** work,which began in the slums of Lagos,has garnered international admiration.

关键词： player lives beyond

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

Cerebral and muscle tissue oxygenation during exercise in healthy adults: A systematic review

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Journal of Sport and Health Science 2024年第4期13卷 459-471,F0003页

作者： Diego Orcioli-Silva Victor Spiandor Beretta Paulo Cezar Rocha Santos Felipe Marroni Rasteiro Anita Brum Marostegan Rodrigo Vitorio Claudio alexandre Gobatto Fulvia Barros Manchado-Gobatto Laboratory of Applied Sport Physiology(LAFAE) School of Applied Sciences(FCA)University of Campinas(UNICAMP)Limeira 13484-350Brazil Posture and Gait Studies Laboratory(LEPLO) Institute of BiosciencesSao Paulo State University(UNESP)Rio Claro 13506-900Brazil Physical Education Department School of Technology and SciencesSao Paulo State University(UNESP)Presidente Prudente 19060-900Brazil Department of Computer Science&Applied Mathematics Weizmann Institute of ScienceRehovot 7610001Israel Center of Advanced Technologies in Rehabilitation Sheba Medical CenterRamat Gan 5265601Israel Department of Sport Exercise and RehabilitationNorthumbria UniversityNewcastle upon Tyne NE18STUK

Background:Near-infrared spectroscopy(NIRS)technology has allowed for the measurement of cerebral and skeletal muscle oxygenation simultaneously during *** this technology has been growing and is now successfully used in laboratory and sports settings,this systematic review aimed to synthesize the evidence and enhance an integrative understanding of bloodﬂow adjustments and oxygen(O_(2))changes(i.e.,the balance between O_(2) delivery and O_(2) consumption)within the cerebral and muscle systems during ***:A systematic review was conducted using PubMed,Embase,Scopus,and Web of Science databases to search for relevant studies that simultaneously investigated cerebral and muscle hemodynamic changes using the near-infrared spectroscopy system during *** review considered manuscripts written in English and available before February 9,*** step of screening involved evaluation by 2 inde-pendent authors,with disagreements resolved by a third *** Joanna Briggs Institute Critical Appraisal Checklist was used to assess the methodological quality of the ***:Twenty studies were included,of which 80%had good methodological quality,and involved 290 young or middle-aged *** types of exercises were used to assess cerebral and muscle hemodynamic changes,such as cycling(n=11),treadmill(n=1),knee extension(n=5),isometric contraction of biceps brachii(n=3),and duet swim routines(n=1).The cerebral hemodynamics anal-ysis was focused on the frontal cortex(n=20),while in the muscle,the analysis involved vastus lateralis(n=18),gastrocnemius(n=3),biceps brachii(n=5),deltoid(n=1),and intercostal muscle(n=1).Overall,muscle deoxygenation increases during exercise,reaching a plateau in voluntary exhaustion,while in the brain,oxyhemoglobin concentration increases with exercise intensity,reaching a plateau or declining at the exhaustion ***:Muscle and cerebral oxygenation respond differently to exercise,with muscle

关键词： Near-infrared spectroscopy Hemodynamic Blood flow Brain Muscle metabolism

Determination of Total Heavy Metals Content in Local Antidote Manufacturing Resources

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Open Journal of Applied Sciences 2024年第8期14卷 2144-2153页

作者： alexandre Ngama Mwabi Pierre Yoniene Yassa Vestine Ntakarutimana Doctoral School University of Burundi Bujumbura Burundi Research Center in Natural Science and Environment (CRSNE) University of Burundi Bujumbura Burundi Faculty of Medicine University of Kaziba (UNIKAZ) Bukavu Democratic Republic of Congo (DRC) Department of Chemistry Faculty of Sciences University of Burundi Bujumbura Burundi

The present work was initiated for searching and evaluating the total heavy metal content in some selected local resources used by traditional healers in locally made antidotes to search for their toxicity. Elekat public slaughterhouse in the city of Bukavu, the central market of Kadutu and in the Ruzizi plain, precisely in Sange city, have been the purchased centers. The samples of bull and cow horns, oil palm nut shells, cow bones, ginger, black pepper and Mwenga salt were used. The spectrometric method has been used to carry out heavy metal content in each local resource using the atomic absorption spectrometer (VARIAN 1275). The heavy metals found and their average content are as follows: copper (Cu: 124.79 mg/kg), lead (Pb: 76.41 mg/kg), chromium (Cr: 33.9 mg/kg), zinc (Zn: 190.86 mg/kg), Arsenic (As: 107.41 mg/kg) and cadmium (Cd: 0.05 mg/kg). The averages of total heavy metal contents for all samples are below the standard of each one. The determination of the heavy metal contents in these samples allows evaluating human intoxication risk. These results show that antidote technology can be run without any toxicity risk and showed statistically significant differences compared to the controls (p 0.05) for chromium, zinc and cadmium have been recorded. However, most of the heavy metals molecules being thioloprives and then bioccumulatives, antidotes made from them shall not be consumed during a long period.

关键词： Heavy Metals Local Resources Contamination Antidote