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Localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on Si(111) substrates

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Journal of Semiconductors 2024年第9期 34-42页

作者： Leonarde do nascimento Rodrigues Wesley Fiorio lnoch marcos L.F.Gomes Odilon D.D.Couto Jr. Bráulio S.Archanjo Sukarno Olavo Ferreira Physics Department Federal University of Vi?osa Instituto de Física Gleb Wataghin Universidade Estadual de Campinas National Institute of Metrology Quality and Technology (Inmetro) Materials Metrology Division (DIMAT)

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

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Redefining Commercial Bus Models in Brazil

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Journal of Civil Engineering and Architecture 2012年第5期6卷 557-573页

作者： Artur Carlos de Morais maria Luiza Bastos da Silva e Galindo Heitor Pereira do nascimento Wilier Luciano Carvalho Marcos Fleming Balieiro Alves and Joaquim Jose Guilherme de Aragao

Currently, Brazilian buses are divided in three categories： city buses, intercity buses and coaches. That categorization results from the understanding that citizens only need to move around urban perimeters. However, the current bus models available do not fully meet legal demands or cater for all of society＇s demands. Rural workers and students that live in rural areas also must be conveyed in buses and minibuses. Municipal and state directives prohibit employers to convey them in improper vehicles, such as trucks. Social demands, on the other hand, can be i[llustrated by federal and state programs that provide vehicles to transport students who dwell in rural settings. Accordingly, this paper proposes a new categorization of bus models available in the Brazilian market, which should account for the unique local operating conditions rural buses face, instead of only considering the type of service they provide. Further, a purpose-built vehicle is suggested i[n order to cater for the needs of rural workers and students. Rural students represent, in average, five million rural school bus riders.

关键词： Bus models rural matters rural vehicle category.

Natural Disaster Risk in Municipal Solid Waste Disposal Sites Using GIS: A Case Study in São Paulo State, Brazil

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Journal of Water Resource and Protection 2017年第11期9卷 1213-1224页

作者： Victor Fernandez nascimento Anahi Chimini Sobral Pedro R. Andrade Nazli Yesiller Jean Pierre Henry Balbaud Ometto Earth System Science Center (CCST) National Institute for Space Research (INPE) S&atilde o José dos Campos Brazil Global Waste Research Institute (GWRI) California Polytechnic State University (Cal Poly) San Luis Obispo CA USA

Natural disasters and finding suitable areas to dispose of municipal solid waste (MSW) are two major global challenges, both of which have several influences in the water resources and are related to climatic change, especially in developing countries like Brazil. Currently the risk of natural disasters is not utilized in the process of locating areas to dispose of MSW. This study, using geographic information system (GIS), analyzed spatially the susceptibility for landslide and flooding hazards in MSW disposal sites in S?o Paulo state, Brazil. The results showed that more than 90% of sanitary and ditch landfills are located in null, very low and low hazard classes (P0, P1 and P2). However, in this remaining 10% of landfills we still have approximately 55% of the total municipal solid waste disposed into susceptible areas with middle, high and very high hazard classes (P3, P4 and P5). This shows that S?o Paulo MSW disposal sites need more attention and control to prevent the occurrence of landslide/flooding and consequently the mitigation of environmental, economic and social impacts. In addition, the use of GIS is proved to be an appropriate tool to carry out this type of analysis, so we recommend that the risk of natural disasters should be taken into consideration in the process of finding landfill areas. Mainly, because, there is a tendency for extreme weather events to increase causing more flood and landslide events and consequently contributing to water scarcity and water degradation.

关键词： Landfills Spatial Analysis Susceptibility Hazard Landslides Flood

Modeling Environmental Susceptibility of Municipal Solid Waste Disposal Sites: A Case Study in São Paulo State, Brazil

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Journal of Geographic Information System 2017年第1期9卷 8-33页

作者： Victor Fernandez nascimento Anahi Chimini Sobral Pedro R. Andrade Jean Pierre Henry Balbaud Ometto Nazli Yesiller Earth System Science Center (CCST) National Institute for Space Research (INPE) Sao José dos Campos Brazil Global Waste Research Institute (GWRI) California Polytechnic State University (Cal Poly) San Luis Obispo USA

The large excess of solid waste generated in cities is a result of population growth and economic development. Properly managing this municipal solid waste (MSW) is a challenge, mainly in underdeveloped and developing countries where financial concerns are an added problem. From the environmental point of view, a major issue is properly disposing MSW taking into consideration a wide range of factors, and working with different spatial data. In this study, we used geographic information system (GIS) to perform multi-criteria decision analysis (MCDA) conducted by analytical hierarchy process (AHP). The development of the environmental impact susceptibility model (EISM) for municipal solid waste disposal sites (MSWDS) applied to the state of Sao Paulo, Brazil considered factors such as geology, pedology, geomorphology, water resources, and climate represented by fifteen associated sub-factors. The results indicated that more than 82% of Sao Paulo’s territory is situated in areas with very low, low, and medium environmental impact susceptibility categories. However, in the remaining 18% of the state land area, 85 landfills are located in areas with high and very high environmental impact susceptibility categories. These results are alarming because these 85 landfills receive approximately 17,886 tons of MSW on a daily basis, which corresponds to 46% of all municipal solid waste disposed in Sao Paulo state. Therefore, decision makers, urban planners and policymakers could use the findings of the EISM towards mitigating the environmental impacts caused by MSWDS.

关键词： Modeling Geographic Information System (GIS) Environmental Impact Municipal Solid Waste Landfills Multi-Criteria Decision Analysis (MCDA) Analytic Hierarchy Process (AHP)

Locating Power and Decision-Making： Social Production of Space in Juiz de Fora, Brazil

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Journal of Civil Engineering and Architecture 2017年第5期11卷 494-499页

作者： Victor nascimento Carina Cardoso marcelo Ribeiro Tavares mariane Garicia Unanue PatriciaMaya-Monteiro Frederico Braida Antonio Colchete Filho Department of Design History and Theory Federal University of Juiz de Fora Juiz de Fora 36036-900 Brazil Graduate Program in Urbanism Federal University of Rio de Janeiro Rio de Janeiro 21941-901 Brazil Department of Architecture and Urbanism Federal University of Goias Goias 76600-000 Brazil Graduate Program in Urbanism Federal University of Rio de Janeiro Rio de Janeiro 21941-901 Brazil Department of Urbanism and Environment Federal University of Rio de Janeiro Rio de Janeiro 21941-901 Brazil Department of Design Representation and Technology Federal University of Juiz de Fora Juiz de Fora 36036-900 Brazil

This paper aims to discuss how the shaping of a city, Juiz de Fora, in Brazil, has resulted from the power of location of some social agents and from their disputes on the production of space. First, it introduces the concept of social production of space, emphasizing the role of social agents in urban processes. Then, it presents specific aspects of the history of Juiz de Fora＂ its origins and how social agents and forces have played a significant role in shaping the built environment of the city--specially represented by main streets of the city. The paper studies how the social agents, with their different visions and goals, have influenced the process of formation and development of the city. This demonstrates the complexity of the existing relationships between the built environment and the social context that is specific to the city. Different urban forces fight for city spaces, construct and modify its territory so that their needs are fulfilled. Their strength, their experiences and efforts, and their ideas of a city are inscribed in urban landscapes; in similar ways, these are revealed by the city paths we follow here.

关键词： Social production of space social agents social site constructed environment urban history.

Agroecosystems, Landscapes and Knowledge of Family Farmers from AramaçáIsland, Upper Solimões Region, Amazon

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Agricultural Sciences 2018年第10期9卷 1369-1387页

作者： Ayrton Luiz Urizzi martins Sandra do nascimento Noda Hiroshi Noda Lúcia Helena Pinheiro martins Elisabete Brocki Faculdade de Ciências Agrárias (FCA) Universidade Federal do Amazonas (UFAM) Manaus Brazil Instituto Nacional de Pesquisas da Amazô nia (INPA) Manaus Brazil Núcleo de Etnoecologia da Amazô nia (NETNO) Universidade Federal do Amazonas (UFAM) Manaus Brazil Escola Superior de Tecnologia (EST) Universidade do Estado do Amazonas (UEA) Manaus Brazil

The family farmer’s knowledge about floodplains agroecosystems dynamics is part of agrobiodiversity conservation cognitive strategies. This is because the conservation in floodplains is conditioned by the ecophysiological adaptation to the period and flood gradient of the agricultural lands and by the transformations promoted in the environment by the waters pulse. The aim of this study was to understand the cognitive strategies expressed in the organized meaning of agroecosystems by local knowledge, related to the geomorphological dynamics of the Aramaçá Island, Amazonas, Brazil. In this research, the Case Study and Ethnoecology were adopted as approach, taking the systemic complexity paradigm as a theoretical framework. To do so, it was necessary to establish a dialogue with the local knowledge through multitemporal analyses of satellite images, historical series of hydrological data, as well as cartographic documents of the locality. The floodplains amphibian mark, as a living organism in permanent autopoietic process, seems to be imprinted in the family farmer’s knowledge. In order to live in the floodplains and of floodplains, it is necessary, above all, to develop a cognitive ability capable of understanding not only the rivers action on the lands, but also that of the lands on the rivers as well. Therefore, the geomorphological dynamics in the spaces managed by the family farmers impose on them, risks and uncertainties, demanding from them strategies that allow knowing and dealing with this complexity.

关键词： Geomorphological Dynamics Ethnoecology Floodplains Amazonia

Are There Schizophrenia Genetic markers and Mutations? A Systematic Review and Meta-Analyses

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Health 2017年第5期9卷 811-838页

作者： maria Auxiliadora Brasil Sampaio Cardoso Tárcia Januário do nascimento Gabriel Pereira Bernardo Lorena Pereira Bernardo maria Mirelle Ferreira Leite Barbosa Pedro Januário nascimento Neto Danilo Ferreira de Sousa Antonio Gilvan Teixeira Júnior marcos Antonio Pereira de Lima marcial Moreno Moreira David de Sousa Gregório Lídia Coelho do nascimento Santos Modesto Leite Rolim Neto Postgraduate Program in Health Science FMABC Santo André Brazil Faculty of Medicine Estacio (FMJ) Juazeiro do Norte Brazil Federal University of Cariri (UFCA) Faculty of Medicine Barbalha Brazil Science without Borders fellow at University of Liverpool Liverpool UK

Background: Schizophrenia is a severe psychiatric disorder with a complex genetic factor determining its disease onset. Nevertheless, it is not clear in this mental disorder. Objective: To conduct a systematic review of articles regarding the genetic markers and mutations in schizophrenia. Methods: A systematic review of articles on genetic markers and mutations in schizophrenia, published from January 1, 2011, to September 7, 2015, on SCOPUS database was carried out. Search terms were “Genetic markers”, “Mutation”, and “Schizophrenia”. Results: Of the 527 retrieved studies, 31 met the eligibility criteria. Genetic polymorphism, Immune-associated genes, TCF4 and ZNF804A association with microRNA, Neuregulin gene, Chromosome 13q32 and 11p15.4, genes involved in glutamatergic via schizophrenia and brain structure, appeared to be associated with the origin of schizophrenia. Conclusion: Some studies show genes involved in several pathways leading to the disease pathogenesis such as that one related with the dopaminergic and immune system, or rare alleles. Some genes present no involvement in the etiology of this mental disorder. These findings clarify the genetic complexity of schizophrenia and affirm that together, the genes have an overall effect greater than the sum of the individual effect of each gene.

关键词： Schizophrenia Genetic markers Mutations Systematic Review

Crystal-oriented wrinkles with origami-type junctions in few-layer hexagonal boron nitride

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Nano Research 2015年第5期8卷 1680-1688页

作者： Camilla K. Oliveira Egleidson F. A. Gomes mariana C. Prado Thonimar V. Alencar Regiane nascimento Leandro M. Malard Ronaldo J. C. Batista Alan B. de Oliveira Helio Chacham Ana M. de Paula Bernardo R, A. Neves Departamento de Fisica ICEx Universidade Federal de Minas Gerais - UFMG C.P. 702 30123-970 - Belo Horizonte Brazil Departamento de Fisica ICEB Universidade Federal de Ouro Preto - UFOP 35400-000 - Ouro Preto Brazil

Understanding layer interplay is the key to utilizing layered heterostructures formed by the stacking of different two-dimensional materials for device applications. Boron nitride has been demonstrated to be an ideal substrate on which to build graphene devices with improved mobilities. Here we present studies on the morphology and optical response of annealed few-layer hexagonal boron nitride flakes deposited on a silicon substrate that reveal the formation of linear wrinkles along well-defined crystallographic directions. The wrinkles formed a network of primarily threefold and occasionally fourfold origami-type junctions throughout the sample, and all threefold junctions and wrinkles formed along the armchair crystallographic direction. Furthermore, molecular dynamics simulations yielded, through spontaneous symmetry breaking, wrinkle junction morphologies that are consistent with both the experimental results and the proposed origami-folding model. Our findings indicate that this morphology may be a general feature of several two-dimensional materials under proper stress-strain conditions, resulting in direct consequences in device strain engineering.

关键词： hexagonal boron nitride 2D materials wrinkles origami folding annealing

A Variational Approach for Numerically Solving the Two-Component Radial Dirac Equation for One-Particle Systems

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Journal of Modern Physics 2012年第4期3卷 350-354页

作者： Antonio L. A. Fonseca Daniel L. nascimento Fabio F. Monteiro marco A. Amato Faculdade UnB Planaltina University of Brasília Brasília Brazil Institute of Physics and International Center for Condensed Matter University of Brasília Brasília Brazil

In this paper we propose a numerical approach to solve the relativistic Dirac equation suitable for computational calculations of one-electron systems. A variational procedure is carried out similar to the well-known Hylleraas computational method. An application of the method to hydrogen isoelectronic atoms is presented, showing its consistency and high accuracy, relative to the exact analytical eigenvalues.

关键词： One-Electron Systems 2D Dirac Equation No-Inertial Frames Variational Approach