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Publicações - ciências exatas e da terra

Selective synthesis of monolaurin catalyzed by layered zinc laurate WILLIAM FRANCO DA SILVA; Débora Kochepka; Lais Pastre Dill; WYPYCH, FERNANDO; Claudiney Soares Cordeiro Reaction Kinetics Mechanisms and Catalysis, v. 1, n. 1, p. 1-13, 2019 DOI Palavra-chave: layered carboxylate; zinc laurate; monolaurina Áreas do conhecimento: Ciências Exatas e da Terra; Engenharia e Ciencia de Materiais; Materiais de Baixa Dimensionalidade Estrutural; Ciências Exatas e da Terra; Química; Físico-Química; Cinética Química e Catálise resumo ... In the present study, zinc laurate (ZL) was synthesized by precipitation and characterized by X-ray diffraction, Fourier transform infrared spectroscopy and thermal analysis. ZL was applied for monolaurin synthesis by esterification of lauric acid with glycerol using a 23 factorial design to determine the best conditions for monolaurin production. Conversion of nearly to 70% was achieved by using a lauric acid:glycerol molar ratio of 1:1, 2 wt % of catalyst and 140 °C, reaching to 33% of monolaurin selectivity. Statistical analyses at a confidence level of 95% indicated that the decrease in lauric acid:glycerol molar ratio was significant to enhance the monolaurin production. Moreover, the solid was able to be reused, preserving its original structure and the catalytic activity, which indicated the potential use in continuous processes.
Single-step formation of Cr 2 N nanoparticles by pulsed laser irradiation GUBERT, G.; OLIVEIRA, R. C.; COSTA, D. S.; METZGER, G. K.; Irineu Mazzaro; KELLERMANN, G.; Evaldo Ribeiro; José Varalda; Dante Homero Mosca JOURNAL OF APPLIED PHYSICS, v. 125, n. 2, p. 024301 2019 DOI Palavra-chave: Cr2N; nanoparticles; pulsed laser irradiation resumo ... Chromium nitride nanoparticles with mean diameter distribution between 0.8 nm and 30 nm were produced by laser irradiation of a chromium target immersed in liquid nitrogen. Cr was directly converte...
Single-step formation of Cr 2 N nanoparticles by pulsed laser irradiation GUBERT, G.; OLIVEIRA, R. C.; COSTA, D. S.; METZGER, G. K.; MAZZARO, IRINEU; KELLERMANN, G.; Evaldo Ribeiro; José Varalda; Dante Homero Mosca JOURNAL OF APPLIED PHYSICS, v. 125, n. 2, p. 024301 2019 DOI Palavra-chave: Cr2N; nanoparticles; pulsed laser irradiation Áreas do conhecimento: Ciências Exatas e da Terra; Física; Física da Matéria Condensada; Ciências Exatas e da Terra; Física; Física da Matéria Condensada; Materiais Magnéticos e Propriedades Magnéticas resumo ... Chromium nitride nanoparticles with mean diameter distribution between 0.8 nm and 30 nm were produced by laser irradiation of a chromium target immersed in liquid nitrogen. Cr was directly converte...
Sobrevida de pessoas com hantavirose diagnosticadas no Estado do Paraná, Brasil Daniele Akemi Arita; EMIKO SHIMAKURA, SILVIA Cadernos de Saude Publica, v. 35, n. 3, p. e00105518 2019 DOI Palavra-chave: infecções por hantavirus; análise de sobrevida; MORTALIDADE Áreas do conhecimento: Ciências da Saúde; Saúde Coletiva; Epidemiologia; Ciências Exatas e da Terra; Probabilidade e Estatística; Probabilidade e Estatística Aplicadas; Análise de Sobrevivência resumo ... Resumo: Hantavirose é uma doença emergente e com impacto na saúde pública. Por apresentar sinais...
Sound waves in gaseous mixtures induced by vibro-thermal excitation at arbitrary rarefaction and sound frequency Denize Kalempa; Felix Sharipov; SILVA, JÚLIO CONTI VACUUM, v. 159, p. 82-98, 2019 DOI Palavra-chave: acoustics; Mixture; Boltzmann Equation; Discrete Velocity Method Áreas do conhecimento: Engenharias; Engenharia Mecânica; Fenômenos de Transporte; Dinâmica dos Gases; Ciências Exatas e da Terra; Física; Física dos Fluídos, Física de Plasmas e Descargas Elétricas; Cinética e Teoria de Transporte de Fluídos; Propriedades Físicas de Gases resumo ...
Spatial correlation analysis between topographic parameters for defining the geomorphometric diversity index: application in the environmental protection area of the Serra da Esperança (state of Paraná, Brazil) DA SILVA, JULIO MANOEL FRANÇA; Leonardo José Cordeiro Santos; OKA-FIORI, CHISATO Environmental Earth Sciences, v. 78, n. 12, p. 342-360, 2019 DOI Palavra-chave: Landforms; Geographic information system; Geomorphometry; Geomorphodiversity Áreas do conhecimento: Ciências Exatas e da Terra; Geociências; Geografia Física; Geomorfologia resumo ... The present work, by focusing on geomorphological modeling within the context of geodiversity, addresses the definition of a diversity index based on the evaluation of the association between topographic variables corresponding to the North district of the Environmental Protection Area of the Serra da Esperança, state of Paraná, Brazil. In light of resources provided by digital modeling of the relief as well as by spatial statistics, the study consisted in submitting geomorphometric parameters to Shannon’s diversity index and evaluating the resulting data by means of spatial correlation analysis, which in its turn was guided by the Bivariate Moran’s index. Association of the variables in different crosstab phases resulted in the identification of those with positive spatial correlation, presenting high diversity mainly over and around escarpments, in consonance with the initial assumption of this study. In the same vein, we confirmed the hypothesis that a limited amount of topographic features does enable measurement of topographic variations, which justifies the introduction of the term geomorphometric diversity index. Since the study has a methodological character, comparative analyses between quantitative resources are necessary for addressing specific objectives within distinct themes and areas of interest.
Spike-burst chimera states in an adaptive exponential integrate-and-fire neuronal network SANTOS, MOISES S.; GREBOGI, CELSO; PROTACHEVICZ, PAULO R.; IAROSZ, KELLY C.; CALDAS, I; VIANA, R. L.; BORGES, FERNANDO S.; REN, HAI-PENG; SZEZECH, JOSÉ D.; BATISTA, ANTONIO M. CHAOS, v. 29, n. 4, p. 043106 2019 DOI Palavra-chave: Redes neuronais Áreas do conhecimento: Ciências Exatas e da Terra; Neurociência Computacional; Ciências Exatas e da Terra; Física; Física Geral; Dinamica Nao-Linear e Caos resumo ... Chimera states are spatiotemporal patterns in which coherence and incoherence coexist. We observe the coexistence of synchronous (coherent) and desynchronous (incoherent) domains in a neuronal netw...
Synchronous patterns and intermittency in a network induced by the rewiring of connections and coupling BUDZINSKI, R. C.; BOARETTO, B. R. R.; Thiago de Lima Prado; VIANA, R. L.; LOPES, S. R. CHAOS, v. 29, n. 12, p. 123132 2019 DOI Palavra-chave: Redes neuronais Áreas do conhecimento: Ciências Exatas e da Terra; Neurociência Computacional resumo ... The connection architecture plays an important role in the synchronization of networks, where the presence of local and nonlocal connection structures are found in many systems, such as the neural ...
Synthesis and antioxidant activity of new lipophilic dihydropyridines DA COSTA CABRERA, DIEGO; SANTA-HELENA, EDUARDA; LEAL, HELOISA P.; de Moura, Renata Rodrigues; NERY, LUIZ EDUARDO MAIA; GONÇALVES, CARLA AMORIM NEVES; RUSSOWSKY, DENNIS; Marcelo Gonçalves Montes D'Oca BIOORGANIC CHEMISTRY, v. 84, p. 1-16, 2019 DOI Home page Palavra-chave: Nifedipine; antioxidant activity; antihypertensive drug; fatty dihydropyridines; Sulfamic acid Áreas do conhecimento: Ciências Exatas e da Terra; Química Orgânica; Síntese Orgânica; Ciências Exatas e da Terra; Química; Quimica Medicinal resumo ...
Synthesis and characterization on microalgae fatty acids or Aloe vera oil microcapsules Luiza Badke; Bruno Campos da Silva; Agne Roani Carvalho; D Taher; Izabel C R Vidotti; Cláudia Eliana Bruno Marino Polimeros-Ciencia e Tecnologia, v. 29, n. 3, p. 1-9, 2019 DOI Palavra-chave: óleos essenciais; microcápsulas; coacervação complexa Áreas do conhecimento: Engenharias; Engenharia de Materiais e Metalúrgica; BIOMATERIAIS; Ciências Exatas e da Terra; Química; Físico-Química; Eletroquímica resumo ... Abstract It’s proposed a single methodology for the encapsulation of Aloe vera oil or microalgae...

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