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A comprehensive study on the processing of Co:ZnO nanostructured ceramics:Defect chemistry engineering and grain growth kinetics

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Journal of Materials Science & Technology 2023年第7期138卷 221-232页

作者： R.T.da silva J.M.Morbec G.Rahman H.B.de Carvalho Universidade Federal de Ouro Preto-UFOP Ouro PretoMG 35400-000Brazil School of Chemical and Physical Sciences Keele UniversityKeele ST55BGUnited Kingdom Department of Physics Quaid-i-Azam UniversityIslamabad 45320Pakistan Universidade Federal de Alfenas-UNIFAL Alfenas 37130-000Brazi

In this report,we present a systematic study on the preparation of Co:ZnO ceramics via a standard solid-state route from different Co precursors(Co_(3)O_(4),CoO,and metallic Co)and atmospheres(O_(2)and Ar).Particular emphasis is given to defect chemistry engineering and the sintering growth ***-principles calculations based on density functional theory are employed to determine the formation en-ergy of the main point defects in ZnO and Co:ZnO *** on the theoretical results,a set of chemical reactions is *** microstructural characterization is also performed to determine the degree of Co incorporation into the ZnO *** samples prepared in Ar atmosphere and metal-lic Co present the highest Co solubility limit(lower apparent Co incorporation activation energy)due to the incongruent ZnO *** of the parameters of the sintering growth kinetics reveals that Co_(3)O_(4)is the best sintering additive to achieve larger grain sizes,and possible higher densi-ties,in both sintering atmospheres,while metallic Co is the best to achieve the smallest grain size with higher Co concentration and homogeneous spatial distribution for a subsequent reduction of *** results show that the sintering in O_(2)effectively promotes zinc vacancies in the ZnO structure,while the sintering in Ar promotes zinc interstitial *** findings contribute to understanding the preparation of Co-doped ZnO ceramics and the sintering growth kinetics,which may improve the state of the art in processing the material at both bulk and nanometric scales.

关键词： Multifunctionality Zinc oxide Defect engineering Growth kinetics

Characterization of Nickel Alloy 600 with Ultra-Fine Structure Processed by Severe Plastic Deformation Technique (SPD)

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Journal of Materials Science and Chemical Engineering 2017年第4期5卷 33-44页

作者： Waldemar Alfredo Monteiro Silvio Luis Ventavele da silva Luciana Ventavele da silva Arnaldo Homobono Paes de Andrade Luis carlos Elias da silva Nuclear and Energy Research Institute IPEN Cidade Universitária S&atilde o Paulo Brasil

High strength nickel based alloys are used in a multitude of advanced systems where lightweight, high power density mechanical power transmission systems are required. Components such as gears, bearings and shafts could be made significantly smaller and more durable if a major improvement in nickel based alloy mechanical properties could be achieved. An important refinement in grain size (includes nanometric level) is thought to be a promising method for achieving fundamental improvements in mechanical properties. Grain size is known to have a significant effect on the mechanical behavior of materials. One of the most favorable methods of achieving extreme grain refinement is by subjecting the materials to severe plastic deformation (SPD). The principal micro-structural variations in superalloys are the precipitation amount and morphology, grain size and the distribution of carbide precipitation that could reduce the mechanical properties of the alloys. This work shows optical and transmission electron microscopy analysis and also hardness data after severe plastic deformation (pure shear stress).

关键词： Nickel Based Alloys Severe Plastic Deformation Hardness Microstructure Microscopy

Assessment of hybrid geoids in Chile and Spain,combining GGM and GNSS/Leveling observations

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Geodesy and Geodynamics 2021年第2期12卷 65-92页

作者： Jose Antonio Tarrio Mosquera Marcelo Caverlotti silva Fernando Isla carlos Prado University of Santiago of Chile(USACH) Faculty of EngineeringGeographical Engineering DepartmentChile Geographic Military Institute Chile

This research presents the results for analyses done to five geopotential global models(GGM),comparing them with ground data from GNSS and leveling in heterogenic zones from the geodetic perspective,in Chile and *** the official and complete implementation of the International Height Reference Frame(IHRF)has not yet been established,the vertical geodetic system of many countries is not calculated on a global scale;instead,it is calculated by the variation of relative heights between one or more local tide gauges,such as in the case of Spain and *** aspect creates regional and specific altimetry data,which disables the use of GGM to directly obtain the orthometric height of the vertical reference system(VRS)from the GNSS *** models currently reach centimetric precision due to their high resolution but are directly incompatible for a local *** solve this,we expose in this article the contrast between geometric geoidal undulation(ellipsoidal heights and orthometric data from the leveling networks in Spain and Chile)with the geoidal undulation in more recent models and higher resolution:Earth Gravitational Model 2008(EGM08),European Improved Gravity model of the Earth by New techniques(EIGEN6 C4),Gravity Observation Combination(GOCO05 C),Experimental Gravity Field Model(XGM2016),and Ultra-High Resolution Global Geopotential Model(SGG-UGM),adjusting the residual between both referential heights by different parametric models and polynomials of determined *** evaluated,their geoidal undulations are combined with GNSS/leveling data from the corresponding VRS to generate a correcting surface,which is also known as a hybrid geoid,resulting in a model of optimal adjustment for the combination of five parameters of the EIGEN-6 C4 with orthometric heights and ellipsoids of both Chile and *** results show 2-3 cm precisions,which were statistically analyzed to determine the suitability for *** final products are three grids of indep

关键词： GNSS levelling Correcting surface IHRS SIRGAS EIGEN-6C4

Object-based image analysis supported by data mining to discriminate large areas of soybean

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International Journal of Digital Earth 2019年第3期12卷 270-292页

作者： carlos Antonio da silva Junior Marcos Rafael Nanni José Francisco de Oliveira-Júnior Everson Cezar Paulo Eduardo Teodoro Rafael Coll Delgado Luciano Shozo Shiratsuchi Muhammad Shakir Marcelo Luiz Chicati Geotechnology Applied in Agriculture and Forest(GAAF) State University of Mato Grosso(UNEMAT)Alta FlorestaMato GrossoBrazil Department of Agronomy(daG/PGA) State University of Maringá(UEM)MaringáParanáBrazil Institute of Atmospheric Sciences(ICAT) Federal University of Alagoas(UFAL)MaceióAlagoasBrazil Federal University of Mato Grosso do Sul(UFMS) Chapadão do SulMato Grosso do SulBrazil Department of Environmental Sciences(DCA) Forestry Institute(IF)Federal Rural University of Rio de Janeiro(UFRRJ)SeropédicaRio de JaneiroBrazil AgCenter Louisiana State University(LSU)Baton RougeLAUSA Institute of Space Technology Islamabad Pakistan IslamabadPakistan

This research aimed to analyze the possibility to estimate and automatically map large areas of soybean cultivation through the use of MODIS(Moderate-Resolution Imaging Spectroradiometer)*** major techniques were used:GEOgraphic-Object-Based Image Analysis(GEOBIA)and data Mining(DM).In order to obtain the images,the segmentation algorithm implemented by Definiens Developer was used.A decision tree(DT)was created from a training set previously ***-series of images from the MODIS sensor aboard the Terra satellite were acquired in order to represent the wide variation of the vegetation pattern along the soybean crop *** time-series data were used only for the CEI ***,to compare the results obtained from GEOBIA,the slicing technique was used at the CEI *** the training,the DT was applied to the vegetation indices generating the thematic map of the spatial distribution of *** accordance with the error matrix and kappa parameter analysis,tests for statistical significance were *** indicate that the classification achieved by Kappa coefficients is *** short,the obtained results proved that combining vegetation indices and time-series data using GEOBIA return promising results for mapping soybean plantation on a regional scale.

关键词： GEOBIA time-series vegetation indices MODIS vegetation dynamics

Pulp and Paper from Sugarcane:Properties of Rind and Core Fractions

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Journal of Renewable Materials 2018年第2期6卷 160-168页

作者： Lísias Pereira Novo Julien Bras Mohamed Naceur Belgacem Antonio Aprigio da silva Curvelo Department of Materials Engineering Sao Carlos School of EngineeringUniversity of Sao PauloAv.Joao Dagnone 110013563-120Sao CarlosSao PauloBrazil Department of Physical Chemistry Sao Carlos Institute of ChemistryUniversity of Sao PauloAv.Trabalhador Sao Carlense 40013560-970Sao CarlosSao PauloBrazil Grenoble Alpes University LGP2F-38000 GrenobleFrance CNRS LGP2F-38000 GrenobleFrance

Two distinct lignocellulosic fractions(rind and core)can be obtained through a physical separation of sugarcane *** presenting differences in morphology,both fractions can be employed to produce pulps and *** pulps and paper sheets produced from the core and rind fractions were characterized by their chemical composition,physical properties and mechanical *** pulps obtained from the core presented a higher amount of fines,lower drainage ability and rendered denser and stiffer *** pulps from the rind,which have a higher content of fibers and higher degree of polymerization,produced sheets with higher air permeability and water *** paper sheets presented mechanical and physical properties comparable to commercial papers and papers from different cellulosic *** different properties exhibited by the papers produced from each fraction allow their use for distinct purposes,and expands the opportunities in the context of sugarcane biorefinery.

关键词： Sugarcane core and rind fractions papermaking pulp and paper

Impact of SARS-CoV-2 infection during pregnancy on postnatal brain development:The potential role of glial cells

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BIOCELL 2022年第12期46卷 2517-2523页

作者： LARISSA daNIELE BOBERMIN LARA SCOPEL MEDEIROS FERNANda WEBER GIANCARLO TOMAZZONI DE OLIVEIRA LUCÉLIA SANTI WALTER ORLANDO BEYS-da-silva carlos-ALBERTO GONÇALVES ANDRÉQUINCOZES-SANTOS Programa de Pós-Graduação emNeurociências Instituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do SulPorto Alegre90050170Brazil Departamento de Bioquímica Instituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do SulPorto Alegre90035003Brazil Faculdade de Farmácia Universidade Federal do Rio Grande do SulPorto Alegre90610000Brazil Hospital de Clínicas de Porto Alegre Porto Alegre90035903Brazil Programa de Pós-Graduação emBiologia Celular eMolecular Centro de BiotecnologiaUniversidade Federal do Rio Grande do SulPorto Alegre91501970Brazil Programa de Pós-Graduação em Ciências Biológicas:Bioquímica Instituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do SulPorto Alegre90035003Brazil

Glial cells are crucial for maintaining central nervous system(CNS)*** actively participate in immune responses,as well as form functional barriers,such as blood-brain barrier(BBB),which restrict the entry of pathogens and inflammatory mediators into the *** general,viral infections during the gestational period can alter the embryonic and fetal environment,and the related inflammatory response may affect neurodevelopment and lead to behavioral dysfunction during later stage of life,as highlighted by our group for Zika virus *** acute respiratory syndrome coronavirus-2(SARS-CoV-2)induces a cytokine storm and,during pregnancy,may be related to a more severe form of the coronavirus disease-19(COVID-19)and also to higher preterm birth ***-CoV-2 can also affect the CNS by inducing neurochemical remodeling in neural cells,which can compromise neuronal plasticity and synaptic ***,the impact of SARS-CoV-2 infection during pregnancy on postnatal CNS,including brain development during childhood and adulthood,remains *** group has recently highlighted the impact of COVID-19 on the expression of molecular markers associated with neuropsychiatric disorders,which are strongly related to the inflammatory ***,based on these relationships,we discussed the impact of SARS-CoV-2 infection either during pregnancy or in critical periods of neurodevelopment as a risk factor for neurological consequences in the offspring later in life,focusing on the potential role of glial ***,it is important to consider future and long-term public health concerns associated with SARS-CoV-2 infection during pregnancy.

关键词： Brain development Glial cells Inflammation Pregnancy SARS-CoV-2

Special Issue on 15th Brazilian Polymer Conference:Biopolymers,Eco-Friendly and Biodegradable Polymers and Other Topics Related to Polymeric Materials Derived from Renewable Materials

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Journal of Renewable Materials 2021年第4期9卷 599-600页

作者： Antonio Aprigio da silva Curvelo Antonio José Felix Carvalho daniel Pasquini São carlos Institute of Chemistry University of São PauloSão Carlos13566-590-SPBrazil São carlos School of Engineering University of São PauloSão Carlos13563-120-SPBrazil Institute of Chemistry Federal University of UberlândiaUberlândia38400-902MGBrazil

This issue of Journal of Renewable Materials is a special issue dedicated to the 15th Brazilian Polymer Conference(15th CBPol)which was held in Bento Gonçalves,Rio Grande do Sul State,Brazil,from 27 to 31 October,2019[1].CBPol is the main scientific forum in the field of polymer science and technology in *** conference has been held biannually since 1991 and in this event had almost 900 participants mainly from Brazil,but also from Argentina,Chile,Peru,USA,Canada,Belgium,France,Great Britain,Portugal and Spain,with 60%students and 40%professionals.A total of 1,100 papers from 2725 authors were presented,from which 25%(280 papers)was in the field of Biomaterials showing the importance of these materials which are in general based on renewable *** 280 works were developed mainly by researchers from Brazilian institutions(universities and research institutes),mainly from the south and southeast regions of the *** subject of more than 70%of the works was dedicated on vegetal raw materials,medicinal applications,packaging and composite materials.

关键词： materials showing annually

The Cartography and the Spatial Representations:Search by Perfect Map

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Journal of Geographic Information System 2014年第6期6卷 624-635页

作者： Christian Nunes da silva Joao Marcio Palheta da silva Clay Anderson Nunes Chagas carlos Jorge Nogueira Castro Federal University of Para(UFPA) BelemBrazil

The activities of the professionals working on cartographic products have been highlighted especially in recent years. The history, the concepts and categories of cartography cannot be neglected in using this type of tool since the use of elements that make a cartographic product, as an example: map, chart, plan, globe, and a scale model should be used since the unawareness of techniques of cartography and the absence of the components of a map may hinder the understanding of what is intended to represent cartographically. This text is a contribution to the discussion of advances in cartography including errors and absence of maps, including a brief discussion of the characteristics of cartographic language nowadays and the search for perfection in cartography.

关键词： Cartography Cartographic Evolution Geographic Space Spatial Representations Perfect Map

Thermal Fatigue Analysis of a NPP Steam Generator Injection Nozzle Model Subjected to Thermal Stratification

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材料科学与工程（中英文A版） 2012年第5期2卷 391-401页

作者： da silva Luiz Leite Cimini Junior carlos Alberto Mansur TaniusRodrigues CNEN/CDTN Av. Presidente Antonio Carlos 6627- Campus UFMG Pampulha Belo Horizonte MG CEP 30123-970 Brazil UNICAMP Rua Mendeleyev 200- Cidade Universitaria "Zeferino Vaz" Campinas SP CEP 13083-860 Brazil