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Publicações - ciências exatas e da terra

Microwave-irradiated acetylation of glycerol catalyzed by acid activated clays Lais Pastre Dill; DEBORA MEREDIANE KOCHEPKA; André Melinski; WYPYCH, FERNANDO; Claudiney Soares Cordeiro Reaction Kinetics Mechanisms and Catalysis, v. 127, n. 2, p. 991-1004, 2019 DOI Home page Palavra-chave: glycerol; clay minerals; acetylation; heterogeneous catalysis 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 this study, the investigation of the effects related to glycerol and acetic acid esterification over solid acid catalysts under microwave radiation by full factorial design 23 is described. Using clay minerals activated with H3PO4 as catalysts it was possible to produce 26.4 wt% of acetins with molar ratio of 1:3 (glycerol:acetic acid), at 90 °C and using 10 wt% catalysts (in relation to glycerol mass) in 1 h of reaction. On the other hand, under the same conditions and conventional heating, 22.5 wt% of acetins were obtained, without selectivity, while under microwave radiation 67% of produced acetins were monoacetin, which is an important intermediate in organic synthesis. The influence of independent variables at 95% confidence level for reactions under microwave was evaluated and the molar ratio (acetic acid:glycerol) had a negative effect on acetin production. Finally, the catalysts were characterized after its exposure to conventional and microwave heating and no structural modifications were observed, which indicates the possibility of catalysts reuse.
Microwave-irradiated acetylation of glycerol catalyzed by acid activated clays DILL, LAÍS PASTRE; KOCHEPKA, DÉBORA MEREDIANE; MELINSKI, ANDRÉ; WYPYCH, FERNANDO; Claudiney Soares Cordeiro Reaction Kinetics Mechanisms and Catalysis, v. 1, p. 1-14, 2019 DOI Palavra-chave: heterogeneous catalysis; Acid activated clays; glycerol; Acetins; Microwave heating Áreas do conhecimento: Ciências Exatas e da Terra; Química Orgânica; Síntese Orgânica; Ciências Exatas e da Terra; Química; Química Inorgânica; Físico Química Inorgânica resumo ... In this study, the investigation of the effects related to glycerol and acetic acid esterification over solid acid catalysts under microwave radiation by full factorial design 23 is described. Using clay minerals activated with H3PO4 as catalysts it was possible to produce 26.4 wt% of acetins with molar ratio of 1:3 (glycerol:acetic acid), at 90 °C and using 10 wt% catalysts (in relation to glycerol mass) in 1 h of reaction. On the other hand, under the same conditions and conventional heating, 22.5 wt% of acetins were obtained, without selectivity, while under microwave radiation 67% of produced acetins were monoacetin, which is an important intermediate in organic synthesis. The influence of independent variables at 95% confidence level for reactions under microwave was evaluated and the molar ratio (acetic acid:glycerol) had a negative effect on acetin production. Finally, the catalysts were characterized after its exposure to conventional and microwave heating and no structural modifications were observed, which indicates the possibility of catalysts reuse.
Mixed carbonate-siliciclastic microfacies from Permian deposits of western Gondwana: Evidence of gradual marine to continental transition or episodes of marine transgression? NG, CHRISTIANO; Cristina Silveira Vega; MARANHÃO, MARIA DA SAUDADE ARAUJO SANTOS SEDIMENTARY GEOLOGY, v. 390, p. 62-82, 2019 DOI Home page Palavra-chave: Permo-Triassic; Paleoinvertebrates; Microfacies Áreas do conhecimento: Ciências Exatas e da Terra; Ciência da Computação; Metodologia e Técnicas da Computação; Engenharia de Software; Ciências Exatas e da Terra; Geociências; Geologia; Paleontologia Estratigráfica; Ciências Exatas e da Terra; Geociências; Paleoecologia resumo ... At the end of the Paleozoic, several intracratonic basins developed in Gondwana, including the Paraná Basin in Western Gondwana. Permian sedimentary u…
Modelagem e mapeamento de áreas de perigo de inundação urbana na cidade de Francisco Beltrão (Brasil) Ariadne de Farias; Francisco de Assis Mendonça physis Terrae, v. 1, n. 2019, p. 73-93, 2019 Home page Palavra-chave: Inundações urbanas; impactos socioambientais; riscos ambientais; Riscos hibridos; Vulnerabilidade socio-ambiental; Francisco Beltrão Áreas do conhecimento: Ciências Exatas e da Terra; Geografia Física; Pedologia resumo ...
Modified β-cyclodextrin/amlodipine inclusion complexes: Preparation and application in aqueous systems DALMOLIN, MARA CRISTINA; DA SILVA, CINTIA ENES; LUNELLI, CARLOS EDUARDO; SORAIA ZAIONCZ; Paulo V Farago; ZAWADZKI, SÔNIA F. JOURNAL OF MOLECULAR LIQUIDS, v. 276, p. 531-540, 2019 DOI Palavra-chave: Cyclodextrin; Hexanoic anhydride; Modification; Amlodipine; Inclusion complexes; evaluation Áreas do conhecimento: Ciências da Saúde; Farmacologia; Transmissão Neuromuscular; Ciências Exatas e da Terra; Química; Química de Materiais; Ciências Exatas e da Terra; Química; Química Orgânica; Síntese Orgânica resumo ...
MORPHOSTRATIGRAPHY OF FERRUGINOUS DURICRUSTS IN THE NORTHWEST OF PARANÁ FUMIYA, MARCEL HIDEYUKI; Leonardo José Cordeiro Santos; RIFFEL, SILVANA BRESSAN REVISTA BRASILEIRA DE GEOMORFOLOGIA, v. 20, n. 4, p. 707-717, 2019 DOI Palavra-chave: Northwest of Paraná; ferruginous duricrust; Relief Áreas do conhecimento: Ciências Exatas e da Terra; Ciência da Computação; Metodologia e Técnicas da Computação; Engenharia de Software resumo ... (en) Soils constitute an important mean for studying the conditioning processes of the evolution of the relief, considering that in them materials related to events modeling the relief can be preserved. In the Northwest region of Paraná, a manifestation of ferruginous duricrust related to relief sculpture is observed, but there are no detailed studies on these deposits. In this sense, this work aims to analyze these ferruginous materials present in the study area, through the morphological description of profiles with duricrusts, as well as to study these materials by X-ray diffraction and micromorphology, seeking to understand the current organization of ferruginous materials on top of hillocks and hills. Therefore, a mapping of relief features supported by ferruginous duricrusts, previously identified by Fumiya et al . , (2016) was used. A morphological description of profiles with ferruginous duricrust in 14 relief features showed that 11 features present truncations between horizons and colluvial layers, indicating that probably the duricrusts are rudaceous paleopavement, that were covered by colluvium.
Multi-species okadaic acid contamination and human poisoning during a massive bloom of Dinophysis acuminata complex in southern Brazil Luiz Laureno Mafra Júnior; Paula Karine Wormsbecher Nolli; Lucas E Mota; Camila Domit; Marcelo Soeth; Ligia Ferreira Granja da Luz; Bruna Fernanda Sobrinho; Julia Gonçalves Leal; Maikon Di Domenico HARMFUL ALGAE, v. 89, p. 101662 2019 DOI Palavra-chave: harmful algae; dsp; lipophilic toxins; Toxin in food webs; Seafood intoxication; New toxin vectors Áreas do conhecimento: Ciências Exatas e da Terra; Oceanografia Biológica; Interação entre os Organismos Marinhos e os Parâmetros Ambientais; Ciências Exatas e da Terra; Oceanografia; Oceanografia Biológica; Aquicultura; Ciências Exatas e da Terra; Oceanografia; Oceanografia Biológica; Toxicologia de Dinoflagelados resumo ...
Multifunctionality of zinc carboxylate to produce acylglycerols, free fatty acids and fatty acids methyl esters ESCORSIM, ALEXIS M.; HAMERSKI, FABIANE; RAMOS, LUIZ P.; Marcos Lúcio Corazza; Claudiney Soares Cordeiro FUEL, v. 244, p. 569-579, 2019 DOI Palavra-chave: palm oil; esterification; hydrolysis; Layered carboxylates; transesterification Áreas do conhecimento: Ciências Exatas e da Terra; Química Orgânica; Síntese Orgânica resumo ...
Muscodor brasiliensis sp. nov. produces volatile organic compounds with activity against Penicillium digitatum PENA, LORENA C.; KAVA, VANESSA; JUNGKLAUS, GUSTAVO H.; SAVI, DAIANI C.; FERREIRA-MABA, LISANDRA; SERVIENSKI, ANDRÉ; Beatriz Helena Lameiro Noronha Sales Maia; ANNIES, VINICIUS; GALLI-TERASAWA, LYGIA V.; Chirlei Glienke MICROBIOLOGICAL RESEARCH, v. 221, p. 28-35, 2019 DOI Palavra-chave: Muscodor; volatile Áreas do conhecimento: Ciências Biológicas; Genética Vegetal; Ciências Exatas e da Terra; Química; Química Orgânica; Química dos Produtos Naturais resumo ...
Naming Content on the Network Layer MANNES, ELISA; Carlos Alberto Maziero ACM COMPUTING SURVEYS, v. 52, p. 1-28, 2019 DOI Palavra-chave: Redes Centradas em Informação; Segurança de sistemas Áreas do conhecimento: Ciências Exatas e da Terra; Ciência da Computação; Sistemas de Computação; Arquitetura de Sistemas de Computação; Ciências Exatas e da Terra; Ciência da Computação; Sistemas de Computação; Teleinformática resumo ... The Information-Centric Network (ICN) paradigm is a future Internet approach aiming to tackle the Internet architectural problems and inefficiencies, by swapping the main entity of the network arch...

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