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Journal of Materials Science & Technology 2013年第8期29卷 747-751页

作者： Marcelo Marques Tusi Michele Brandalise Nataly Soares de Oliveira Polanco Olandir Vercino Correa Antonio Carlos da Silva Juan Carlo Villalba Fauze Jaco Anaissi Almir Oliveira Neto estevam Vitorio Spinac universidade regional integrada do alto uruguai e das missoes-uri Av.Batista Bonoto Sobrinhos/nSao Vicente97700-000 SantiagoRSBrazil Instituto de Pesquisas energticas e Nucleares-IPeN/CNeN-SP Av.Prof.Lineu Prestes2242Cidade Universitria05508-900 Sao PauloSPBrazil universidade estadual do Centro-Oeste-UNICeNTRO R.Simeao Varela de S 03Vila Carli85040-080 GuarapuavaPRBrazil

Ni/Carbon was prepared in two steps： initially cellulose as carbon source and NiCl2·6H2O as catalyst of the carbonization process were submitted to hydrothermal treatment at 200 ℃ and further to thermal treatment at 900 ℃ under argon atmosphere. The obtained material contains Ni nanoparticles with face-centered cubic （fcc） structure dispersed on amorphous carbon with graphitic domains. PtRu/C electrocatalysts （carbon- supported PtRu nanoparticles） were prepared by an alcohol-reduction process using Ni/Carbon as support. The materials were characterized by thermogravimetric analysis, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy and tested as anodes in single direct methanol fuel cell （DMFC）. The performances of PtRu/C electrocatalysts using Ni/Carbon as support were superior to those obtained for PtRu/C using commercial carbon black Vulcan XC72 as support.

关键词： Cellulose Hydrothermal carbonization Alcohol-reduction process PtRu/C electrocatalysts Direct methanol fuel cell

Application of the Distance to Natural (D2N) Index and Statistical Analysis of Different Anthropic Uses of the Río Grande De Comitán Watershed, Chiapas, México

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Journal of Geoscience and environment Protection 2022年第11期10卷 225-235页

作者： Flor Magali Aguilar López Dayana Almeida Yuri Tavares Rocha eliziane Carla Scariot Waldir José Gaspar Roberto Bonifaz Alfonzo elisabete Maria Zanin Alberto Carvalho Peret José eduardo dos Santos universidade Federal de Sã o Carlos S&#227 o Carlos Brazil universidade de Sã o Paulo S&#227 o Paulo Brazil InstitutoFederal de Sã o Paulo Mat&#227 o Brazil universidade Federal do Mato Grosso Cuiabá Brazil Universidad Nacional Autónoma de México México City México universidade regional integrada do alto uruguai e das Missõ es Erechim Brazil

The intensification of anthropic uses (i.e., increase of the hemerobic condition) threatens the remnants of native vegetation due to the reduction of its self-regulation capacity. In this research, the Distance to Nature (D2N) index for land use and land cover was applied in the Río Grande de Comitán watershed (Southern Mexico) to answer the following questions: 1) What were the land use dynamics observed in the Rio Grande de Comitán watershed in the trajectory through 1999, 2009 and 2019? 2) does the subcategorization of the D2N allow one to identify which anthropic uses influence more the territorial expression of the watershed? To answer these questions, we performed a supervised classification of land use and land cover was performed in this watershed, and for the D2N index, the classification was simplified to three-category scale for the subcategorization of the anthropic component. Through Principal Component Analysis (PCA), we identified that agricultural anthropogenic use had the greatest influence on territorial expression. The reported scenario indicates a trend of gradual and continuous reduction of naturalness over the last 20 years. Additionally, the D2N index proved to be a useful tool to demonstrate both the anthropic impact, with the simplified scale, and the component that most influences the territory, by subcategorizing the anthropic scale.

关键词： Anthropic Land-Use Pressures Spatio-Temporal Principal Component Analysis (PCA) environmental Planning Nature Conservation

A Closed-Form Solution of a Kinetic Integral equation for Rarefied Gas Flow in a Cylindrical Duct

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Applied Mathematics 2014年第10期5卷 1516-1527页

作者： Carmo Henrique Kamphorst Patricia Rodrigues Liliane Basso Barichello Departamento de Ciencias exatas e da Terra Universidade Regional Integrada do Alto Uruguai e das Missoes(URI)Frederico WestphalenBrazil Departamento de Ciencias Agronomicas e Ambientais Universidade Federal de Santa Maria(UFSM)Frederico WestphalenBrazil Instituto de Matematica Universidade Federal do Rio Grande do Sul(UFRGS)Porto AlegreBrazil

A spectral method based on Hermite cubic splines expansions combined with a collocation scheme is used to develop a solution for the vector form integral S-model kinetic equation describing rarefied gas flows in cylindrical geometry. Some manipulations are made to facilitate the computational treatment of the singularities inherent to the kernel. Numerical results for the simulation of flows generated by pressure and thermal gradients, Poiseuille and thermal-creep problems, are presented.

关键词： Rarefied Gas Dynamics Integral equation S-Model Collocation Schemes

Assessing Naturalness Changes Resulting from a Historical Land Use in Brazil South Region: An Analysis of the 1986-2016 Period

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Journal of environmental Protection 2019年第2期10卷 149-163页

作者： Ivan Luís Rovani José eduardo dos Santos Vanderlei Secretti Decian elisabete Maria Zanin PPG-eRN/UFSCar Universidade Federal de S&atilde o Carlos (UFSCar) S&atilde o Carlos Brazil Department of Biological Science Universidade Regional Integrada do Alto Uruguai e das Miss&otilde es (uri) Erechim Brazil

The effects of land use and cover changes and the application of the Urbanity Index were analyzed to identify critical or non-critical naturalness scenery in the Northern Region of Rio Grande do Sul (Brazil), over a period of 30 years. Between 1986 and 2016, the main significant land use change was the reduction of the agricultural anthropic and the increase of the natural vegetation land use areas. About 90% - 80% of the total study areas were characterized by anthropic pattern features, with a predominantly agricultural matrix. The conversion of agricultural anthropic into natural areas resulted in increased naturalness landscape and a gain in the stock of natural capital. The increase in the natural vegetation area, mainly to the north and east of the region, set in a steep relief, became remarkable after 1990. The Urbanity Index values evidenced a highest naturalness condition (natural vegetation areas) to the northern and eastern, while a smaller naturalness condition (agricultural and non-agricultural areas) to the southern and western and central of the Northern Region of Rio Grande do Sul. These changes are related to a non-impaired (northern and eastern) and a impaired scenery (southern, western and central portion) of the ecological sustainability of the Northern Region of Rio Grande do Sul, after a 30-year period (1986-2016). These results pointed out that land use transitions resulted in a consolidated farming scenario in which agricultural intensification coincided with the reduction of farming area and increased naturalness as a reverse trend to the agricultural frontier dynamics.

关键词： Land Use and Cover Native Vegetation Urbanity Index environmental Management

Delving into the variations in tree species composition and richness across south american subtropical atlantic and Pampean forests

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Journal of Plant ecology 2015年第3期8卷 242-260页

作者： Ary T.Oliveira-Filho Jean C.Budke João A.Jarenkow Pedro V.eisenlohr Danilo R.M.Neves Departamento de Botânica Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisAv.Antônio Carlos6627Belo HorizonteMinas Gerais31270-901Brazil Departamento de Ciências Biológicas Universidade Regional Integrada do Alto Uruguai e das MissõesAv.Sete de Setembro1621ErechimRio Grande do Sul99700-000Brazil Departamento de Botânica Instituto de BiociênciasUniversidade Federal do Rio Grande do SulAv.Bento Gonçalves9500Porto AlegreRio Grande do Sul91501-970Brazil Royal Botanic Garden edinburgh Inverleith RowEdinburghEH35LRUK

Aims We analyse here the variations in species composition and richness and the geographic ranges of the tree species occurring in south american subtropical atlantic and Pampean *** goals were to assess(i)the floristic consistency of usual classifications based on vegetation physiognomy,climate and elevation;(ii)the leading role of temperature-related variables on the variations in species composition and richness;(iii)the predominance of species with tropical-subtropical ranges,possibly as a result of forest expansion over grasslands after the last glacial maximum(LGM);(iv)the restriction of most subtropical endemics to stressful habitats as a possible result of past forest refuges during the *** The region was defined by the Tropic of Capricorn to the north,the rio de la Plata to the south,the atlantic shoreline to the east and the catchment areas of the upper Paranáand uruguay rivers to the *** analyses,multiple regression modelling and variance partition analyses were performed on a database containing 63994 occurrence records of 1555 tree species in 491 forest sites and 48 environmental *** species were also classified according to their known geographic *** Findingsa main differentiation in species composition and richness was observed between the eastern windward coastlands(rain and cloud forests)and western leeward hinterlands(Araucaria and semi-decid-uous forests).Pre-defined forest types on both sides were consistent with variations in tree species composition,which were significantly related to both environmental variables and spatial proximity,with extremes of low temperature playing a chief *** species rich-ness declined substantially towards the south and also from rain to seasonal forests and towards the highland summits and sandy *** richness was significantly correlated with both minimum temperature and actual *** 91%of the subtropical flora is shared with the

关键词： distribution patterns endemic species floristic connections macro-scale species richness spatial and climatic predictors subtropical forests

Historical Land Use/Cover Changes and the Hemeroby Levels of a Bio-Cultural Landscape: Past, Present and Future

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Journal of Geographic Information System 2017年第5期9卷 576-590页

作者： Angela Terumi Fushita José eduardo dos Santos Yuri Tavares Rocha elisabete Maria Zanin Center of engineering Modeling and Applied Social Sciences Universidade Federal do ABC (UFABC) Santo André Brazil Pos-Graduate Programme in ecology and Natural Resources Universidade Federal de S&#227 o Carlos (UFSCar) S&#227 o Carlos Brazil Department of Geography Universidade de S&#227 o Paulo (USP) S&#227 o Paulo Brazil Department of Biological Science Universidade Regional Integrada do Alto Uruguai e das Miss&#245 es (uri) Erechim Brazil

The urbanization of a campus landscape has required much space for this expansion, reinforcing the status of geographical space as a limited resource. We analyzed the effects of land cover change assessed over temporal dataset on composition and configuration dynamics of UFSCar (Federal University of São Carlos) campus landscape, based on a descriptive view of the hemeroby levels, over a 54-year period (1962-2016), in order to understand the impacts of past anthropogenic induced landscape change and inform decision making with regard to biodiversity management. The classification of land use/cover dynamics, over time, was obtained based on screen digitizing of aerial photos and LandSat imagery. An ordinal scale ranging from ahemerob to metahemerob was applied to assess the hemerobiotic state of each land use type. Currently, The UFSCar landscape campus configures a biocultural mosaic in different stages of hemeroby. Thus a campus landscape dynamics model, which can be denoted as “forestry-conservation-urban model”, anthropogenic landscape is replaced by natural one, later by land cover reflecting the spatial anthropization process. Through time, two hemerobiotic trajectories were identified, in which 1) an euhemerob landscape matrix is substituted by an ahemerob one, resulting in increased naturalness of the campus landscape, and then 2) metahemerob patch types will later on increasing as a consequence of ongoing urbanization. expressive amount of ahemerob patches in campus landscape fulfills one of the conditions for maintenance of the capacity for self-regulation and sustainability of a biocultural landscape. This framework provides an essential tool supporting with essential information about current and historical landscape sustainability for campus landscape management and support decision making process. The main institutional challenge for campus landscape sustainable management lies in the balance between the competitors of the campus landscape matrix:

关键词： Land Use Change Trajectories Urbanization Conservation Landscape Sustainable Management