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Dynamic Modeling and Experimental Damping Identification of a Flexible Structure

材料科学与工程（中英文A版） 2013年第7期3卷 505-509页

作者： marcelo rodolfo de assis Alvaro Manoel de Souza Soares JoAo Bosco Goncalves Pedro Paulo Leite do Prado Mechanieal Engineering department University of Taubate Campus da Juta Taubatd 12.060-440 SP Brazil Eletrical Engineering department University of Taubatd Campus da Juta Taubatd 12.060-440 SP Brazil

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Petrogenesis of Granites from the Ediacaran Socorro Batholith,SE Brazil:Constraints from Zircon Dating,Geochemistry and Sr-Nd-Hf Isotopes

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Journal of Earth Science 2021年第6期32卷 1397-1414页

作者： Bárbara Bueno Toledo Valdecir de assis Janasi Instituto de Geociências USPCEP 05508-900S∼ao PauloSPBrazil

Whole rock elemental and Sr-Nd isotope geochemistry and in situ zircon Hf isotope geochemistry were used to identify the sources of the Neoproterozoic granites from the Socorro batholith,Socorro-GuaxupéNappe(SGN),South Brasilia Orogen,*** trace elements and Hf isotope geochemistry provided information about sources and crystallization(T,f_(O2))*** main types of granites built the bulk of the batholiths,beginning with probably pre-collisional~640–630 Ma charnockites,and ending with~610 Ma voluminous post-collisional high-K calc-alkaline(HKCA)Ⅰ-type granites(Bragan?a Paulista-type).Several types of leucogranites were generated from 625 to 610 Ma,spanning the interval from collisional to post-collisional *** charnockite bodies occur in the study area:the~640 Ma Socorro charnockite has remarkable chemical similarities with Braganca Paulista-type granites,but higherε_(Nd)(t)=-6.1 and average zirconε_(Hf)(t)=-9.1 and lower^(86)Sr/^(87)Sr_(t)(0.7093)values,indicative of more juvenile and water-poor ***~633 Ma Atibaia charnockite has distinct geochemical signature(lower Mg^(#)and Sr content;higher Zr),more negativeε_(Nd)(t)=-14.1,similar average zirconε_(Hf)(t)=-8.9,and much higher^(86)Sr/^(87)Sr_(t)=0.7197,probably reflecting a larger component from old *** predominant~610 Ma Bragan?a Paulista-type granites were emplaced in a post-collisional setting,and correspond to porphyritic biotite-hornblende monzogranites of high-K calc-alkaline character with 61 wt.%–67 wt.%SiO_(2),high Mg^(#)(39–42),Sr/Y(19–40),La/Yb(12–69),highly negativeε_(Nd)(t)(-12.3 to-12.9)and zirconε_(Hf)(t)(-12 to-17)and^(87)Sr/^(86)Sr_(t)=0.7119–*** features are interpreted as indicative of magma generation in a thickened crust,where melts from enriched mantle sources emplaced in the lowermost crust,heated host old continental crust rocks(gneisses and granulites)and partially mixed with their melting *** plutons(SiO_(2)>72 wt.%)occur

关键词： U-Pb dating Socorro-GuaxupéNappe high-K calc-alkaline granites

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Growth and nutrient accumulation of Brazil nut trees(Bertholletia excelsa) in agroforestry at different fertilizer levels

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Journal of Forestry Research 2015年第2期26卷 347-353页

作者： Gotz Schroth Maria do Socorro Souza da Mota Maria Elizabeth de assis Elias C.P. 513 Santarem PA 68109-971 Brazil Centro de Estudos Avanqados de Promoqao Social e Ambiental Av. Mendonqa Furtado 3979 Santarem PA 68040-050 Brazil Universidade Federal do Amazonas Manaus AM 69077-000Brazil

The Brazil nut tree（Bertholletia excelsa） is a frequent component of agroforestry systems in the Amazon because of its adaptation to nutrient-poor upland soils and multiple *** investigated the aboveground biomass production（kg dry weight）,nutrient uptake and requirements（N,P,Ca,Mg,K） of Brazil nut trees of different sizes grown under agroforestry conditions and fertilized at different *** of 70 experimental trees with different size were harvested and stem,branches and leaves were *** contents were determined for three trees of varying *** tree growth was fast,but variability was high,suggesting considerable potential for the improvement of this economically important *** trees responded to increased levels of fertilizer and lime with significantly increased foliar nutrient contents and growth,probably because of the improved availability of Mg and Ca for which the species seems to have a relatively high *** contrast to Brazil nut trees grown in forest or dense plantations,the agroforestry trees invested a substantial part of their biomass and nutrients in large branches and developed spreading *** improve stem form,reduce competition with associated crops for light and recycle nutrients,regular pruning of lower branches or planting arrangements that favor self-pruning are *** measures would also increase the recycling of Ca and Mg,large quantities of which are contained in the branches.

关键词： Allometric equation Amazon Nutrient competition Nutrient recycling Plant mineral nutrition Soil fertility Silviculture

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Impacts of land use and land cover changes on hydrological processes and sediment yield determined using the SWAT model

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International Journal of Sediment Research 2022年第1期37卷 54-69页

作者： Edivaldo Afonso de Oliveira Serr?o Madson Tavares Silva Thomás Rocha Ferreira Lorena Concei??o Paiva de Ataide Cleber assis dos Santos Aline Maria Meiguins de Lima Vicente de Paulo Rodrigues da Silva Francisco de assis Salviano de Sousa denis José Cardoso Gomes Academic Unit of Atmospheric Sciences Federal University of Campina Grande department of Physics Center for Natural and Exact Sciences Federal University of Santa Maria Institute of Technology Civil Engineering Graduate Program Federal University of Pará Earth System Science Center National Institute of Space Research Institute of Geosciences Federal University of Pará

Land use and land cover (LULC) changes strongly affect local hydrology and sediment *** current study focused on a basin in the Brazilian Amazon and had the following three objectives:(1) to perform an effective diagnosis of flow and sediment yield,(2) to evaluate the impacts of LULC changes over the last 40 years on the hydro-sedimentological variables,and (3) to investigate the impacts of the possible trends or breaking points in the flow,surface runoff,and sediment yield *** Soil and Water Assessment Tool (SWAT) model validation showed that the simulated results were consistent with the data measured in the dynamic reproduction of flow ***,changes in LULC altered surface runoff,sediment yield,and flow according to the Mann-Kendall and Pettitt non-parametric *** was also observed that the sub-basins in which pastureland is predominant are more susceptible to increased surface runoff and sediment *** to trend and homogeneity tests,these sub-basins had break points in the time series of these *** the other hand,in the sub-basins whose land cover is predominantly forest,the time series is homogeneous and *** current study highlighted the impacts that 40 years of LULC changes in an Amazonian basin had on hydro-sedimentological variables,which,in turn,can play an important role in changing the hydrological cycle,consequently these changes can also impact diverse human activities in the region,such as agribusiness,livestock,energy production,food security,and public water ***,it is concluded that the SWAT model is a good estimator of hydro-sedimentological processes in Amazonian basins and can be used by decision makers in the management of water and environmental resources.

关键词： Hydrological modeling Sediment yield Amazon basin SWAT model

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ENSO impacts on litter stocks and water holding capacity in secondary forests in eastern Amazonia

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Journal of Forestry Research 2024年第1期35卷 83-89页

作者： Julia Isabella de Matos Rodrigues Walmer Bruno Rocha Martins Victor Pereira de Oliveira Myriam Suelen da Silva Wanzerley Hélio Brito dos Santos Júnior Francisco de assis Oliveira Graduate Program in Forestry Sciences Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Tv.Pau-AmareloCapitão PoçoPará68650-000Brazil National Institute of Amazonia Research Av.Constelação Cruzeiro do SulManausAmazonas 69060-062Brazil

Among the impacts of climate change,there is the intensification of phenomena such as the El Niño South-ern Oscillation(ENSO)responsible for El Niño and La Niñ***,understanding their effects on the functional pro-cesses of forests is ***,this study evaluated the effects of ENSO on litter stock and water holding capac-ity(WHC)in a successional forest in eastern *** occurred in periods with the most rainfall in El Niño(2019)and least in La Niña(2021)*** permanent plots were used to sample *** effects were evident for WHC,higher during El Niñ***,this influence was not clear for litter,as only in the rainy season effects were *** was a positive correlation of WHC with precipitation and humidity,while litter stocks were negatively correlated with temperature and wind *** the subject of this study requires long-term assessments,preliminary results suggests that,depending on the intensity of ENSO,forest functional processes can be strongly impacted and *** conclusion reinforces warnings by the scientific community about the impacts of climate change on the maintenance of litter stocks,decomposition and,consequently,the biogeochemical cycle and essential ecosystem services for the maintenance of Amazonia *** need to develop long-term research to understand the effects of climatic change on litter stocks and water holding capacity is highlighted,especially in Amazonia.

关键词： Seasonality Climate change Succession ecosystem Biogeochemical cycle Amazonia biodiversity

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Impact of Cascade Disconnection of Distributed Energy Resources on Bulk Power System Stability:Modeling and Mitigation Requirements

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Journal of Modern Power Systems and Clean Energy 2023年第2期11卷 412-420页

作者： Fabricio Andrade Mourinho Tatiana Mariano Lessa assis Electrical Engineering department of the Federal University of Rio de Janeiro(COPPE/UFRJ) Rio de JaneiroRJBrazil

This work presents a new approach to establishing the minimum requirements for anti-islanding protection of distributed energy resources(deRs)with focus on bulk power system *** proposed approach aims to avoid cascade disconnection of deRs during major disturbances in the transmission network and to compromise as little as possible the detection of real islanding *** proposed approach concentrates on the rate-of-change of frequency(RoCoF)protection function and it is based on the assessment of dynamic security regions with the incorporation of a new and straightforward approach to represent the disconnection of deRs when analyzing the bulk power system ***,the impact of disconnection of deRs on the Brazilian Interconnected Power System(BIPS)stability is analyzed,highlighting the importance of modeling such disconnection in electromechanical stability studies,even considering low penetration levels of ***,the proposed approach is applied to the BIPS,evidencing its benefits when specifying the minimum requirements of anti-islanding protection,without overestimating them.

关键词： Anti-islanding protection bulk power system stability distributed energy resource(deR) dynamic security region(DSR)

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Use of improved cold-finger technique to assess effects of basicity on heat transfer through solidified mold flux

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Journal of Iron and Steel Research International 2019年第4期26卷 393-402页

作者： Karina Lara Santos assis Petrus Christiaan Pistorius department of Materials Science and Engineering Center for Iron and Steelmaking ResearchCarnegie Mellon UniversityPittsburgh 15213PAUSA

Cold-finger measurements were used to estimate the contact resistance and average thermal conductivity of mold flux films solidified on a water-cooled copper *** industrial mold fluxes,with basicities from low to high,were *** steady-state rate of convective heat transfer between the solid film and liquid flux was compared with calculations based on natural convection correlations;the comparison indicates that the surface of the solid film(in contact with molten flux)is approximately at its solidus *** roughness of the mold flux film in contact with copper was larger for films grown from higher-temperature mold flux and for higher-basicity mold *** glassy(low-basicity)film had an estimated thermal conductivity of 1.1 W/(m K).The crystalline or partially crystalline films had higher estimated thermal conductivities of 2.2-3.2 W/(m K).The measured values of thermal resistance were extrapolated to typical mold flux film thicknesses for industrial conditions;the extrapolations confirmed that the high contact resistance of higher-basicity mold fluxes can yield higher thermal resistances than the low-basicity *** morphology of the rough interface of higherbasicity mold flux films that gives the higher contact resistance is consistent with that observed in previous work and appears not to be directly related to crystallization.

关键词： Mold flux Heat transfer Conduction Contact resistance-Cold-finger technique

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Critical issues in soft rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第3期6卷 186-195页

作者： Milton assis Kanji Polytechnical School University of Sāo Paulo ISRM Technical Commission on Soft Rocks

This paper discusses several efforts made to study and investigate soft rocks, as well as their physico- mechanical characteristics recognized up to now, the problems in their sampling and testing, and the possibility of its reproduction through artificially made soft rocks, The problems in utilizing current and widespread classification systems to some types of weak rocks are also discussed, as well as other problems related to them. Some examples of engineering works in soft rock or in soft ground are added, with emphasis on their types of problems and solutions.

关键词： Rock mechanicsSoft rocksRock propertiesGeomechanical classificationArtificial materials

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Light intensity and hydrogel soil amendment differentially affect growth and photosynthesis of successional tree species

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Journal of Forestry Research 2023年第1期34卷 257-268页

作者： Léo Vieira Leonel Fabrício de Oliveira Reis Fábio Afonso Mazzei Moura de assis Figueiredo Tiago Massi Ferraz Sebastiao de Oliveira Maia Júnior Patrick Costa Silva Jailma Ribeiro de Andrade Graduate Program in Agroecology State University of MaranhaoAv.Lourenco Vieira da Silva1000Jardim Sao CristovaoSao LuísMaranhao 65055-310Brazil State University of Maranhao Av.Lourenco Vieira da Silva1000Jardim Sao CristovaoSao LuísMaranhao 65055-310Brazil Graduate Program in Agriculture and Environment State University of MaranhaoPraca Goncalves Diass/nCentroBalsasMaranhao 65800-000Brazil

Global climate changes have increased temperatures,radiation indexes,and consequently,irregularities in rainfall in mainly tropical countries,considerably hindering plant establishment in recovering degraded *** objective of this study was to evaluate the growth and physiological characteristics of one species of each successional group:pioneer,secondary,and climax when subjected to different light intensities and hydrogel as a soil conditioner during rainy and dry *** experiment was conducted in the ecotone between Brazil’s two largest biomes,the Cerrado and the Amazon in the State of Maranh?*** parameters consisted of three species:Guazuma ulmifolia Lam.(pioneer),Astronium fraxinifolium Schott(secondary),and Cariniana rubra Gardner ex Miers(climax).There were two light intensities:70%and 100%,and two planting conditions:with and without soil conditioner(hydrogel).Gas exchanges were higher during the rainy season;the pioneer and secondary species had greater heights and photosynthetic rates in the dry period;the climax species had the lowest gas exchange and lowest recovery as rainfall *** pioneer and secondary species showed higher physiological plasticity,denoting better adaption to environments with high *** improved the photosynthetic performance of these species in the dry season and in areas with 100%sunlight.

关键词： Irradiance Hydrogel Photosynthetic efficiency Physiological plasticity

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Petrogenesis of granites from the Ediacaran Socorro Batholith， SE Brazil: constrains from zircon dating， geochemistry and Sr-Nd-Hf isotopes

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Journal of Earth Science 2021年

作者： Bárbara Bueno Toledo Valdecir de assis Janasi Instituto de Geociências， USP

Whole rock elemental and Sr-Nd isotope geochemistry and in situ zircon Hf isotope geochemistry were used to identify the sources of the Neoproterozoic granites from the Socorro Batholith， located in Socorro-Guaxupé Nappe （SGN）， south Brasilia Orogen， Brazil. Zircon trace element and Hf isotope geochemistry provided information about sources and crystallization (T， fO2) conditions. Three main types of granites built the bulk of the batholiths， beginning with probably pre-collisional ～640-630 Ma charnockites， and ending with ～610 Ma voluminous post-collisional high-K calc-alkaline （HKCA） I-type granites （Bragan?a Paulista-type）. Several types of leucogranites were generated from 625 to 610 Ma， spanning the interval from collisional to post-collisional tectonics. Two charnockite bodies occur in the study area: the ～640 Ma Socorro Charnockite has remarkable chemical similarities with Bragan?a Paulista-type granites， but higher εNd（t） = -6.1 and average zircon εHf（t） = -9.1 and lower 86Sr/87Sr （t）（0.7093） values， indicative of more juvenile and water-poor source. The ～633 Ma Atibaia Charnockite has distinct geochemical signature （lower Mg# and Sr content; higher Zr）， more negative εNd （t） = -14.1， similar average zircon εHf（t）= -8.9， and much higher 86Sr/87Sr（t）= 0.7197， probably reflecting a larger component from old crust. The predominant ～610 Ma Bragan?a Paulista-type granites were emplaced in a post-collisional setting， and correspond to porphyritic biotite-hornblende monzogranites of high-K calc-alkaline character with 61-67 wt% SiO2， high Mg# （39-42）， Sr/Y （19-40）， La/Yb （12-69）， highly negative εNd （t）（-12.3 to - 12.9） and zircon εHf（t）（-12 to -17） and 87Sr/86Sr（t）= 0.7119-0.7131. These features are interpreted as indicative of magma generation in a thickened crust， where melts from enriched mantle sources emplaced in the lowermost crust， heated host old continental crust rocks （gneisses and granulites） and partially mixed with their melting products. Leucogran

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