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SnO_(2) Dense Ceramic Microwave Sintered with Low Resistivity

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Materials Sciences and Applications 2012年第5期3卷 272-280页

作者： Leinig Antonio Perazolli Gisane Gasparotto Natalia Jaomaci Miguel Ruiz Maria Aparecida Zaghete Bertochi Cesar Renato Foschini Ederson Carlos Aguiar Jose Arara Varela Interdisciplinary Laboratory of Electrochemistry and Ceramics—LIEC Institute of ChemistryPaulista State University“Julio Mesquita Filho”(UNESP)Sao PauloBrasil

The Hall-Héroult process is used for alumina reduction by the use of graphite anodes even though it involves a high emission of carbon dioxide (CO2) and several other organic compounds. Proposals have been made aiming at substituting graphite for a single-phase SnO2-based ceramic with low resistivity and chemical resistance to cryolite, which is characterized as an inconsumable anode, reducing pollutant emissions. To this end, a wide range of studies were carried out on SnO2-based ceramics modified with ZnO as a densification aid doped with the promoters of electrical conductivity such as Nb2O5, Al2O3 and Sb2O3 through a mixture of oxides and hybrid sintering in a microwave oven. The pressed pellets were sintered in a microwave oven up to 1050℃ under a constant heating rate of 10℃/min. After sintering, the density was determined by the Archimedes method, the phases were then characterized by X-ray diffraction, the microstructure and chemical composition resulting from the sintered SnO2-based ceramics were also investigated by field emission scanning electron microscopy (FE-SEM) coupled with an energy-dispersive X-ray spectroscopy (EDS) and the electrical properties were determined by the measurements of the electric field x current density. A single-phase ceramic was obtained with a relative density of above 90% and electrical resistivity of 6.1 Ω·cm at room temperature. The ceramics obtained in this study could be a potential candidate as an inconsumable anode to replace the current fused coke used in the reduction of alumina.

关键词： Tin Oxide Anodic Electrode Inconsumable Anode Microwave Sintering Electrical Resistivity

Urban Sprawl and the Challenges for Urban Planning

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Journal of Environmental Protection 2012年第9期3卷 1010-1019页

作者： Mauricio Polidoro Jose Augusto de Lollo Mirian Vizintim Fernandes Barros Federal university of Sao Carlos Sao CarlosBrazil Federal university of Parana CuritibaBrazil Universidade Estadual paulista julio de mesquita Filho Sao PauloBrazil Londrina state university LondrinaBrazil

Dispersed urbanization, urban planning and management instruments such as zoning, and urban expansion zones, have become increasingly consistent in leading cities toward an uncertain and chaotic future. The urban perimeters of municipalities have been used increasingly in favor agents of the reproduction of unequal urban space, aggravating the process of socio-spatial segregation, the formation of urban gaps and real estate speculation. Inherent to this process, infrastructure, one of the most important components of urban land and one of the most costly for local governments, has become increasingly dispersed and obsolete in the midst of the disordered occupation of the city’s land. Based on the above, this paper aims to analyze the phenomenon of urban sprawl in the city of Londrina by means of geotechnologies and to identify the impacts that the form of land occupation the city has employed may cause on the current and future scenario of the municipality in general. To this end, thematic maps were drawn up from multiple sources, which, allied to a review of the literature, indicate that the municipality of Londrina exhibits intense characteristics of the phenomenon of urban sprawl, leading to consequences for territorial ordering and the egalitarian spatial distribution of essential services to the population.

关键词： Urbanization Geotechnologies Urban Planning Urban Gaps

Brazilian biosafety law and the new breeding technologies

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Frontiers of Agricultural Science and Engineering 2020年第2期7卷 204-210页

作者： Alexandre Lima NEPOMUCENO Renata FUGANTI-PAGLIARINI Maria Sueli Soares FELIPE Hugo Bruno Correa MOLINARI Edivaldo Domingues VELINI Eduardo Romano de Campos PINTO Maria Lucia Zaidan DAGLI Galdino ANDRADE FILHO Patricia Machado Bueno FERNANDES Embrapa Soybean Londrina 86001970Brazil Catholic university of Brasilia Brasilia 70790160Brazil Embrapa Agroenergy Biological Station ParkBrasilia 70770901Brazil paulista state university julio de mesquita Filho Botucatu Faculty of Agronomic SciencesBotucatu 18610307Brazil Embrapa Biotechnology and Genetic Resources—Biological Station Park Brasilia 70770900Brazil Sao Paulo university Veterinary FacultySao Paulo 05508900Brazil Londrina state university Microbiology DepartmentUniversity CampusLondrina 86051990Brazil Espirito Santo Federal university Biotechnology Post GraduationVitoria 29040090Brazil CTNBio(National Biosafety Technical Commission) Brasilia 70610200Brazil

Globally,the area of land cultivated with genetically modified(GM)crops has increased a thousand-fold over the last two *** this technology has become important for food production,the regulatory frameworks that underpin these outcomes are based on a list of requirements for a risk assessment that differ from country to *** recent years,policymakers have had the opportunity to learn from the controversies over transgenics to create effective regulatory milestones for emerging technologies,allowing them to reach their potential for a more sustainable agriculture,ensuring food *** Brazil,Law No.11.105 of 24 March 2005 established a framework with four main organizations responsible for risk assessment and ***,most of new breeding technologies did not exist at that time and were not considered in this ***2016,Normative Resolution No.16 of the National Biosafety Technical Commission(CTNBio)was established to address this gap based on the evaluation of the products obtained through these techniques(termed Innovative Precision Improvement Techniques in the resolution),in a case-by-case consultation ***,if the product is designated to be a GM,the developer will have to go through the biosafety requirements and will be approved only after CTNBio risk *** the product is designated not to be GM(for the purposes of the legislation),then it can be registered using the existing ***,152 GM products are commercially approved in *** 2018,CTNBio assessed the first consultation on commercial release of plants generated using the new breeding technologies and has subsequently approved six *** is expected that many institutions would be able to participate in Brazilian and world markets,developing and introducing new biotechnological solutions and products through a more sustainable approach and without facing public disapproval,a common issue for GM crops.

关键词： Brazilian legislation CTNBio genetically modified crops

Phenolic Compounds Influence Seed Dormancy of Palicourea rigida H.B.K.(Rubiaceae),a Medicinal Plant of the Brazilian Savannah

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American Journal of Plant Sciences 2013年第1期4卷 129-133页

作者： Marielle C.Inácio Rita Maria Moraes Patrícia C.Mendonca Lucas J.F.Morel Suzelei C.Franca Bianca W.Bertoni Ana M.S.Pereira Departamento de Horticultura Universidade Estadual Paulista Julio de Mesquita FilhoBotucatuBrazil National Center for Natu-ral Products Research School of PharmacyThe University of MississippiOxfordUSA Center for Water and Wetland Resources The University of MississippiAbbevilleUSA Departamento de Biotecnologia de Plantas Medicinais Universidade de Ribeirao PretoRibeirao PretoBrazil

Palicourea rigida H.B.K. (Rubiaceae), a medicinal species commonly known as douradinha, has wide distribution across ecosystems in Central and South America. This species exhibits seed dormancy delaying germination until optimal conditions for seedling growth and development are in place. While dormancy ensures species survival, it also presents a technical problem for developing P. rigida’s plant production program. Thus, the objective of this study was to investigate if secondary metabolites present in seeds influence the seed dormancy of P. rigida. Mature fruits were harvested from the native habitat, in the savanna region of the state of Minas Gerais during February 2009, 2010 and 2011. The content of phenolic compounds in the seed of P. rigida was measured, and the allelopathic effects were assessed using the germination of lettuces as model to detect phytotoxicity. The P. rigida seeds geminated at rates varying between 7% and 31% with a Seed Germination Index (SGI) of 0.09. Data suggest that the phenolic compounds present in the seeds may be responsible for seed dormancy.

关键词： Cerrado Douradinha Medicinal Plant Conservation