39 research outputs found
Avaliação do estado da arte do reaproveitamento de rejeitos de barragens de processos de extração e beneficiamento de minério de ferro
O minério de ferro tem papel fundamental na economia brasileira, sendo o Brasil o segundo
maior produtor mundial do mesmo. A sua demanda, principalmente no comércio asiático, é
contínua e necessária para a produção dos mais diversos produtos. A região do Quadrilátero
Ferrífero, no Estado de Minas Gerais, é conhecida como uma das estruturas geológicas mais
relevantes na mineração de minério de ferro no planeta. O processo extrativo e de beneficiação
do minério de ferro gera uma quantidade de resíduos significativa, e quando líquidos, estes
resíduos são armazenados em barragens construídas para conter o grande volume gerado,
ocasionando em custos adicionais de logística para as empresas mineradoras e potenciais
problemas ambientais em casos de acidente. O Brasil sofreu com diversos acidentes de
rompimento de barragens ao longo dos anos, com dois acidentes recentes cobertos pela mídia
nacional: o rompimento de uma barragem de minério de ferro localizada em Mariana, em 2015,
e outra localizada em Brumadinho, em 2019, ambos municípios do Estado de Minas Gerais. O
grande volume de rejeitos contidos nestas barragens atingiu milhares de hectares de florestas
de vegetação de mata atlântica, cidades e rios, estes últimos levando os rejeitos a lugares ainda
mais distantes da origem do acidente. Os danos ambientais tiveram uma extensão expressiva,
causando também a perda de centenas de vidas humanas. Levando em conta a quantidade de
barragens existentes no país, principalmente de rejeitos de minério de ferro, e a gravidade dos
acidentes já ocorridos, o presente trabalho tem por objetivo mapear as últimas inovações
tecnológicas presentes em artigos científicos que ilustrem métodos de reutilização dos rejeitos
de barragens de minério de ferro localizadas no Brasil. Iniciou-se o estudo com uma revisão
bibliográfica, de modo a haver uma melhor compreensão de sua composição e a necessidade
do reuso destes rejeitos. Em seguida, realizou-se uma análise de artigos científicos em bases de
artigos de alta relevância mundial, de modo a entender o nível de conhecimento atual de rotas
tecnológicas alternativas que possam vir a ser viáveis economicamente para a reutilização dos
rejeitos a médio e longo prazo. Com isso, foi possível perceber que há diversas oportunidades
distintas de reutilização dos rejeitos de barragens de minério de ferro brasileiros, como
aplicação dos mesmos na produção de tintas sustentáveis, ladrilhos cerâmicos, pavimentação
urbana, preparação de argamassas, cimentos e concretos, além da síntese de catalisadores para
tratamentos de efluentes, dentre outros. Por fim, foi possível apresentar a potencial capacidade
de exploração destes rejeitos em diversas áreas distintas, com ênfase principalmente na
indústria civil como agregado para cimentos, argamassas e concretos
The Catalytic Gasification of Waste Polymers: Determining the Kinetics of the Sabatier Reaction
This research focuses on advancing the knowledge of a catalytic gasification process as a potential in-situ resource utilization and waste management alternative. This research has significance in a variety of engineering applications, but it is of particular relevance towards reducing landfill waste or as an in-situ resource generation system for space exploration beyond Low Earth Orbit (LEO). This process evolves through a reaction mechanism consisting on two liquid-phase oxidation reactions of long-chain polymers, complemented by two gas-phase reactions. This project focusses on one of the gas phase reactions: one of the main fuel producing reactions, the Sabatier (also referred to as “methanation”) reaction. The primary focus of this project is to analyze experimental data collected for this reaction, and to determine the kinetic parameters of the Sabatier reaction. The research is an outgrowth to previous kinetic determinations available for the reaction. Indeed, the data used to perform the kinetic analysis was originally collected by Lunde and Kester in the 1970s (Ind. Eng. Chem., Process Des. Dev., Vol. 13, No. 1, pp. 27-32, 1974). The kinetic analysis presented here is based on fundamental reactor design equations and was accomplished using numerical techniques not readily available at the time of Lunde and Kester\u27s analysis. The experimental data was split into two sets of data: one set used for parameter estimation, and second set to be used for validation purposes. Comparison with the original approach followed by Lunde and Kester is also provided.https://engagedscholarship.csuohio.edu/u_poster_2015/1045/thumbnail.jp
The Catalytic Gasification of Waste Polymers: Determining the Kinetics of the Sabatier Reaction
This research focuses on advancing the knowledge of a catalytic gasification process as a potential in-situ resource utilization and waste management alternative. This research has significance in a variety of engineering applications, but it is of particular relevance towards reducing landfill waste or as an in-situ resource generation system for space exploration beyond Low Earth Orbit (LEO). This process evolves through a reaction mechanism consisting on two liquid-phase oxidation reactions of long-chain polymers, complemented by two gas-phase reactions. This project focusses on one of the gas phase reactions: one of the main fuel producing reactions, the Sabatier (also referred to as “methanation”) reaction. The primary focus of this project is to analyze experimental data collected for this reaction, and to determine the kinetic parameters of the Sabatier reaction. The research is an outgrowth to previous kinetic determinations available for the reaction. Indeed, the data used to perform the kinetic analysis was originally collected by Lunde and Kester in the 1970s (Ind. Eng. Chem., Process Des. Dev., Vol. 13, No. 1, pp. 27-32, 1974). The kinetic analysis presented here is based on fundamental reactor design equations and was accomplished using numerical techniques not readily available at the time of Lunde and Kester\u27s analysis. The experimental data was split into two sets of data: one set used for parameter estimation, and second set to be used for validation purposes. Comparison with the original approach followed by Lunde and Kester is also provided.https://engagedscholarship.csuohio.edu/u_poster_2015/1045/thumbnail.jp
Cats (fam64a) Abnormal Expression Reduces Clonogenicity Of Hematopoietic Cells
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The CATS (FAM64A) protein interacts with CALM (PICALM) and the leukemic fusion protein CALM/AF10. CATS is highly expressed in leukemia, lymphoma and tumor cell lines and its protein levels strongly correlates with cellular proliferation in both malignant and normal cells. In order to obtain further insight into CATS function we performed an extensive analysis of CATS expression during differentiation of leukemia cell lines. While CATS expression decreased during erythroid, megakaryocytic and monocytic differentiation, a markedly increase was observed in the ATRA induced granulocytic differentiation. Lentivirus mediated silencing of CATS in U937 cell line resulted in somewhat reduced proliferation, altered Cell Cycle progression and lower migratory ability in vitro; however was not sufficient to inhibit tumor growth in xenotransplant model. Of note, CATS knockdown resulted in reduced clonogenicity of CATS-silenced cells and reduced expression of the self-renewal gene, GLI-1. Moreover, retroviral mediated overexpression of the murine Cats in primary bone marrow cells lead to decreased colony formation. Although our in vitro data suggests that CATS play a role in cellular processes important for tumorigenesis, such as Cell Cycle control and clonogenicity, these effects were not observed in vivo.7426838568396Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) [101624/2011-5]Coordenacao de Aperfeicoamento Pessoal de nivel Superior (CAPES)Fundacao de Amparo a Pesquisa de Sao Paulo (FAPESP) [2011/18188-0, 2011/51959-0]Leukaemia and Blood Cancer New Zealandfamily of Marijanna KumerichConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Experimental Analysis of Catalytic Gasification of Polyethylene
Over the last century there has been a global interest in reducing/recycling waste material as well as creating energy from renewable and more eco-friendly sources. Catalytic gasification is one effective method that can promote low-temperature conversion of solid waste to energy, also referred to as “gasification”. The gas mixture produced by gasification of long-chain polymers using ruthenium (or platinum) catalysts consists of hydrogen, methane, carbon monoxide, carbon dioxide, and water. Product mixtures of gasification experiments were analyzed by Gas Chromatography (GC) and post-processed using statistical analysis. Using fundamental reactor design equations along with stoichiometric calculations yielded the percent gasified as well as the reaction selectivity of the process. The solid residues containing ashes, char, ruthenium, and polyethylene unreacted were analyzed in a Differential Scanning Calorimetry (DSC) and a Scanning Electron Microscope (SEM) to identify its components. Quantification of the DSC spectra was used to correlate the thermal characterization of the residues with the unconverted (or non-gasified) after the reaction was quenched. Lastly, the SEM provided information on the microstructure of the residues, their atomic composition, and preliminary assessment of the possibility of catalyst recovery. These results are next to be used in formulating a kinetic mechanism for the liquid- phase oxidation, and thus complete a model of catalytic gasification amenable for scaling-up the process to continuous operation.https://engagedscholarship.csuohio.edu/u_poster_2015/1046/thumbnail.jp
Interação Embalagem-alimento Sobre A Estabilidade De Doce De Cupuaçu (theobroma Grandiflorum Schum.)
Cupuaçu (Theobroma grandiflorum Schum.) is an exotic fruit with a promising economic potential, particularly due to its strong aroma and creamy texture. This study aimed to produce sweetened cupuaçu puree and evaluate the effects of packaging corrosion on its sensory properties and shelf-life in tinplated cans. After 240 days of storage, the commercially sterile product had average sensory analysis scores of 5.89 ± 0.21, 5.39 ± 0.30, 5.45 ± 0.21 and 5.49 ± 0.25, for appearance, aroma, flavor and overall appreciation, respectively. Sensory acceptance scores did not change during storage (p>0.05). Corrosion potential and low tin and iron levels in the product, which are parameters used to evaluate food-packaging interaction, demonstrated the product remained food-safe throughout its shelf-life. Tinplate is a promising packaging material for sweetened cupuaçu puree due to its mechanical and protective properties. Furthermore, tin plating is an economically viable food technology to extend the shelf-life of cupuaçu products and expand its domestic and international markets.2941006101
Interação embalagem-alimento sobre a estabilidade de doce de cupuaçu (theobroma grandiflorum schum.)
Cupuaçu (Theobroma grandiflorum Schum.) is an exotic fruit with a promising economic potential, particularly due to its strong aroma and creamy texture. This study aimed to produce sweetened cupuaçu puree and evaluate the effects of packaging corrosion on its sensory properties and shelf-life in tinplated cans. After 240 days of storage, the commercially sterile product had average sensory analysis scores of 5.89 ± 0.21, 5.39 ± 0.30, 5.45 ± 0.21 and 5.49 ± 0.25, for appearance, aroma, flavor and overall appreciation, respectively. Sensory acceptance scores did not change during storage (p>0.05). Corrosion potential and low tin and iron levels in the product, which are parameters used to evaluate food-packaging interaction, demonstrated the product remained food-safe throughout its shelf-life. Tinplate is a promising packaging material for sweetened cupuaçu puree due to its mechanical and protective properties. Furthermore, tin plating is an economically viable food technology to extend the shelf-life of cupuaçu products and expand its domestic and international markets29410061014Cupuaçu (Theobroma grandiflorum Schum.) é uma fruta exótica, com potencial econômico promissor, especialmente devido ao seu forte aroma e textura cremosa. O objetivo deste estudo foi produzir um doce de cupuaçu e avaliar os efeitos da corrosão da embalagem sobre as propriedades sensoriais e vida útil do produto acondicionado em latas de folha de flandres. Após 240 dias de armazenamento, o produto comercialmente estéril teve pontuações médias de aceitação sensorial de 5,89 ± 0,21, 5,39 ± 0,30, 5,45 ± 0,21 e 5,49 ± 0,25, para a aparência, aroma, sabor e impressão global, respectivamente. As aceitações sensoriais não apresentaram alterações durante o armazenamento (p>0,05). Medidas de potencial de corrosão e os baixos níveis de estanho e ferro no produto, que são parâmetros utilizados para avaliar a interação entre embalagem e alimento, demonstraram a segurança do produto ao longo da vida de prateleira. Os resultados obtidos mostraram que a folha de flandres é um material de embalagem promissor para o doce de cupuaçu devido às suas propriedades mecânicas e de proteção. O estudo demonstrou ainda que o processamento e acondcionamento em latas estanhadas é uma tecnologia economicamente viável para estender a vida de prateleira de produtos de cupuaçu e expandir seus mercados nacional e internaciona
The Joe Williams Scholarship Fund Concert
List of performers, performances, and scholarship recipients
The Joe Williams Scholarship Fund Concert
Program listing performers and works performed