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Metamorphism and exhumation of basement gneiss domes in the Quadrilátero ferrífero:Two stage dome-and-keel evolution?

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Geoscience frontiers 2019年第5期10卷 1765-1787页

作者： Kathryn Cutts Cristiano Lana fernando Alkmim federico farina Hugo Moreira Viviane coelho Applied Isotope Research Group Departamento de GeologiaEscola de MinasUniversidade Federal de Ouro PretoMorro do Cruzeiro35400-000Ouro PretoMGBrazil Department of Earth Sciences University of GenevaRue des Maraihers 131205GenevaSwitzerland School of Earth and Environmental Sciences University of PortsmouthBurnaby BuildingBurnaby RoadPortsmouthPO1 3QLUK

The presence of dome-and-keel provinces in Archean cratons has been connected with the initiation of plate tectonics on Earth as these features are most commonly observed in Archean *** Quadrilátero ferrífero in Brazil has been identified as a Paleoproterozoic dome-and-keel province for more than three *** prevailing model suggests that it formed during the Rhyacian Transamazonian orogeny,making it unique among dome-and-keel ***,a lack of appropriate lithologies,datable minerals and the metamorphic overprint of later orogenesis has resulted in a cryptic metamorphic record for the formation of this dome-and-keel province.A clinopyroxene-bearing migmatite from the core of the Bacao dome has peak P-T conditions of 5-7 kbar and 700-750 ℃ and a published age of ca.2730 Ma based on U-Pb ages of zircon from leucosomes,suggesting that this age represents the migmatisation event.A fine-grained epidote-albite-titanite assemblage overprints the coarse-grained clinopyroxene and amphibole,giving P-T conditions of 8-9 kbar and 550℃ with an associated titanite age of ca.2050 Ma.A garnet-bearing amphibolite sample also from the core of the dome has peak P-T conditions of 7-8 kbar and 650-700℃,and texturally late titanite from this sample produces an age of ca.2060 *** additional samples were collected from the edges of the dome.A garnet-gedrite bearing felsic schist produces peak P-T conditions of 8-9 kbar and 650-700℃ on a clockwise P-T *** sample has a U-Pb zircon age of ca.2775 Ma,which could date metamorphism or be the age of its volcaniclastic *** unconstrained titanite from the sample gives an age of ca.2040 Ma.A garnet-bearing amphibolite that occurs as a boudin within the felsic schist gives both zircon and titanite ages of ca.2050 Ma and has peak P-T conditions of 5-6 kbar and 650-700 ℃ on a near isobaric P-T *** amphibolite dike,observed to cross-cut the felsic schist produces a zircon U-Pb age of ca.2760 Ma

关键词： Sao francisco Craton Zircon U-Pb Titanite U-Pb Phase diagrams Dome-and-keel

Managing esophagocutaneous fistula after secondary gastric pullup:A case report

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World Journal of Gastroenterology 2021年第16期27卷 1841-1846页

作者： Johan f Lock Stanislaus Reimer Sebastian Pietryga rafael Jakubietz Sven flemming Alexander Meining Christoph-Thomas Germer florian Seyfried Department of General VisceralTransplantationVascular and Pediatric SurgeryUniversity Hospital WürzburgWürzburg 97080Germany Department of Gastroenterology University Hospital WürzburgWürzburg 97080Germany Department of Trauma- Hand-Plastic-and Reconstructive SurgeryUniversity Hospital WürzburgWürzburg 97080Germany

BACKGROUND Gastric pull-up(GPU)procedures may be complicated by leaks,fistulas,or *** complications are usually managed by endoscopy,but in extreme cases multidisciplinary management including reoperation may be ***,we report a combined endoscopic and surgical approach to manage a failed secondary GPU *** SUMMARY A 70-year-old male with treatment-refractory cervical esophagocutaneous fistula with stenotic remnant esophagus after secondary GPU was transferred to our tertiary *** and systemic infection originating from the infected fistula was resolved by ***,elective esophageal reconstruction with freejejunal interposition was performed with no subsequent adverse *** A multidisciplinary approach involving interventional endoscopists and surgeons successfully managed severe complications arising from a cervical esophagocutaneous fistula after *** treatment may have lowered the perioperative risk to promote primary wound healing after free-jejunal graft interposition.

关键词： Esophageal fistula Gastric fistula Esophageal stenosis Esophageal perforation Endoscopic vacuum therapy free-jejunal graft Autogenous jejunum transplantation Case report

Contribution of inrush current to mechanical failure of power transformers windings

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High Voltage 2019年第4期4卷 300-307页

作者： rafael M.R.Barros Edson Gda Costa Jalberth f.Araujo filipe L.Mde Andrade Tarso V.ferreira Department of Electrical Engineering Federal University of Campina GrandeAprigio Veloso St.882Campina GrandeBrazil

This work presents a study regarding the contribution of inrush current to the occurrence of mechanical fatigue in windings of a power transformer and,consequently,the impact of that phenomenon on the equipment's *** order to perform the study,electromagnetic transient simulations were used to determine the inrush current in a three-phase transformer ***,three-dimensional simulations,based on the finite element method,were performed to determine the electromechanical stresses in the equipment windings,under the effect of the inrush ***,the methods of critical plans and Palmgren–Miner were applied to perform the fatigue *** the results,the impact of inrush current on the integrity of the transformer's windings was determined,as well as,to estimate the reduction of lifespan of the equipment due to inrush *** number of inrushes needed for the total reduction of lifespan of the equipment due to mechanical fatigue was also *** results can be used in the transformers design stage,with the purpose of assisting the evaluation of mechanical withstand of equipment,which can minimise the possibility of failure and increase its lifespan.

关键词： winding fatigue power

Long-term trends in a forest ungulate community: park establishment increases numbers, but poaching is a constant threat

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Zoological Research 2021年第2期42卷 207-211页

作者： Rong Hou rafael Reyna-Hurtado Patrick Omeja Charles Tumwesigye Dipto Sarkar Jan f.Gogarten Colin A.Chapman Department of Anthropology McGill UniversityMontrealQC H3A 2A7Canada Shaanxi Key Laboratory for Animal Conservation Northwest UniversityXi’anShaanxi 710069China El Colegio de la frontera Sur ECOSURCampecheMéxico Makerere University Biological field Station Fort PortalUganda Uganda Wildlife Authority PO Box 3530Kampala 24500Uganda Department of Geography and Environmental Studies Carleton UniversityOttawa M5B 2K3Canada Viral Evolution and Epidemiology of Highly Pathogenic Microorganisms Robert Koch InstituteSeestraße 1013353BerlinGermany School of Life Sciences University of KwaZulu-NatalPietermaritzburgSouth Africa Department of Anthropology Center for the Advanced Study of Human PaleobiologyGeorge Washington UniversityWashington DC 20052USA

DEAR EDITOR Deforestation represents one of the greatest threats to tropical forest mammals, and the situation is greatly exacerbated by bushmeat hunting. To construct informed conservation plans,information must be gathered about responses to habitat degradation, regeneration, and hunting over a sufficiently long period to allow demographic responses.

关键词： forest habitat threat

Ion dynamics into different pore size distributions in supercapacitors under compression

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Journal of Energy Chemistry 2023年第5期80卷 110-119,I0004页

作者： João Pedro Aguiar dos Santos Cesar J.B.Pagan rafael Vicentini Reinaldo f.Teófilo Renato Beraldo Leonardo M.Da Silva Hudson Zanin Brazilian Renewable Energies Center for Innovation on New EnergiesSchool of Electrical and Computer EngineeringUniversity of CampinasAv.Albert Einstein 40CampinasSP13083-852Brazil School of Electrical and Computer Engineering University of CampinasSP 13083-852Brazil Multivariate Chemical Data Analysis Laboratory Department of ChemistryUniversidade Federal de Viçosa36570-900 ViçosaMGBrazil Department of Chemistry Laboratory of Fundamental and Applied ElectrochemistryFederal University of Jequitinhonha and Mucuri's ValleyRodovia MGT 367km 5835000 Alto da Jacuba39100-000DiamantinaMGBrazil

Compressing supercapacitor(SCs)electrode is essential for improving the energy storage characteristics and minimizing ions’distance travel,faradaic reactions,and overall ohmic *** comprising the ion dynamics in SC electrodes under compression are still ***,the ionic dynamics of five aqueous electrolytes in electrodes under compression were studied in this work for tracking electrochemical and structural changes under mechanical stress.A superionic state is formed when the electrode is compressed until the micropores match the dimensions with the electrolyte’s hydrated ion sizes,which increases the *** excessive compression is applied,the accessible pore regions decrease,and the capacitance ***,as the studied hydrated ions have different dimensions,the match between ion/pore sizes *** the LiOH and NaClO4electrolytes,increasing the pressure from 60 to 120 and 100 PSI raised the capacitance from 13.5 to 35.2 f g^(-1)and 30.9 to 39.0 f g^(-1),***,the KOH electrolyte with the lowest and LiCl with the biggest combination of hydrated ion size have their point of maximum capacitance(39.5 and 36.7f g^(-1))achieved at 140 and 80 PSI,*** LiCl and KCl electrolytes,overcompression causes a drop in capacitance higher than 23%.

关键词： Mechanic compression Pore size distribution lon dynamics Activated carbon Supercapacitors

Retention of eucalyptus harvest residues reduces soil compaction caused by deep subsoiling

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Journal of forestry Research 2022年第2期33卷 643-651页

作者： Raphael Oliveira de Melo AymbiréAngeletti da fonseca Nairam félix de Barros Raphael Bragança Alves fernandes rafael da Silva Teixeira Iago Nery Melo Ricardo Previdente Martins Soil Science Department Universidade Federal de ViçosaViçosaMinas GeraisBrazil BRACELL Company AlagoinhasBahiaBrazil

Eucalyptus harvesting,forwarding and soil tillage operations are among the main causes for compaction of forest soils,with potential impacts on *** concern is especially important in areas with soils that are naturally compacted(fragipans and duripans).In these soils,tillage operations include the use of subsoilers that can reach depths of more than one meter and require heavy tractors that exert high pressure on the *** of the ways to try to minimize the effect of this compaction is by retaining harvest *** objective of this study was to evaluate the impacts of eucalyptus harvesting on soil physical attributes,as well as to determine the potential of different types of residue management to reduce compaction from the soil tillage *** experiments were conducted in the same area with a Yellow *** the first experiment,compaction caused by mechanized harvesting with harvester+forwarder was *** the second experiment,different managements of harvest residues were examined as potential modifiers of soil compaction during tillage for new *** this,three managements systems were tested:(1)retention of all harvest residues and litter from the previous rotation(HR+L),(2)retention of litter from the previous rotation(L),and(3)removal of harvest residues and litter from the previous rotation(WR).Before and after harvest,sampling was carried out in the planting rows and inter-rows,and after tillage,samples were collected in the traffic line of the subsoiler-tractor *** both experiments,undisturbed soil samples were collected from the center of the 0-10,10-20,20-40,40-60,and 60-100 cm layers to determine soil density and total *** each period and site of evaluation,mechanical resistance to penetration up to the 60-cm depth was also *** harvesting operation increased soil density at 0-10 and 60-100 cm depths only in the *** of harvest residues and litter(HR+L)after harvesting avoi

关键词： Soil penetration resistance Harvester+forwarder Soil tillage Soil density Cohesive soils

AN IMPLEMENTATION Of THE COLLOCATION METHOD fOR INITIAL VALUE PROBLEMS

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International Journal of Modeling, Simulation, and Scientific Computing 2013年第2期4卷 142-154页

作者： rafael G.CAMPOS fRANCISCO DOM´INGUEZ MOTA facultad de Ciencias fısico-Matematicas Universidad Michoacana 58060 MoreliaMich.Mexico

An implementation of the standard collocation method based on polynomial interpolation is presented in a matrix framework in this *** underlying differentiation matrix can be partitioned to yield a superconvergent implicit multistep-like method to solve the initial value problem *** first-and second-order versions of this method are L-stable.

关键词： IVP ODE collocation differentiation matrix interpolation superconvergence stability

Carbonaceous residues from biomass gasification as catalysts for biodiesel production

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Journal of Natural Gas Chemistry 2012年第3期21卷 246-250页

作者： rafael Luque Antonio Pineda Juan C. Colmenares Juan M. Campelo Antonio A. Romero Juan Carlos Serrano-Ruiz Luisa f. Cabeza Jaime Cot-Gores Departamento de Quimica Organica Universidad de Cardoba Campus de Rabanales Edif icio Marie Curie E-14014 Cardoba Spain Universitat de Lleida GREA lnnovacio Concurrent Lleida Spain Universitat de Lleida GREA lnnovacio Concurrent Lleida Spain

Tars and alkali ashes from biomass gasification processes currently constitute one of the major problems in biomass valorisation, generating clogging of filters and issues related with the purity of syngas production. To date, these waste residues find no useful applications and they are generally disposed upon generation in the gasification process. A detailed analysis of these residues pointed out the presence of high quantities of Ca （〉30 wt%）. TG experiments indicated that a treatment under air at moderate temperatures （400-800 ~C） decomposed the majority of carbon species, while XRD indicated the presence of a crystalline CaO phase. CaO enriched valorized materials turned out to be good heterogeneous catalysts for biodiesel production from vegetable oils, providing moderate to good activities （50%-70% after 12 h） to fatty acid methyl esters in the transesterification of sunflower oil with methanol.

关键词： biomass gasification residues biodiesel catalyst calcium oxide

Grid-Connected PV Solar Energy Converter with Active and Reactive Power Control

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Journal of Energy and Power Engineering 2014年第2期8卷 331-342页

作者： Roberto f. coelho Artur Pagnoncelli Galbiatti Denizar Cruz Martins INEP Power Electronics Institute Federal University of Santa Catarina Florian6polis (SC) 88040-970 Brazil

This work proposes a 12 kW three-phase grid-connected single stage PWM DC-AC converter destined to process the energy provided by a photovoltaic array composed of 57 KC200GT PV modules with high power factor for any solar radiation. The PWM inverter modeling and the control strategy, using dqO transformation, are proposed in order to also allow the system operation as an active power filter, capable to compensate harmonic components and react power generated by the non-linear loads connected to the mains grid. An input voltage clamping technique is proposed to impose the photovoltaic operation on the maximum power point. Simulation and experimental results are presented to validate the proposed methodology for grid connected photovoltaic generation system.

关键词： Active and reactive power dqO transformation grid-connected PV systems three-phase DC-AC PWM converter.