11 documents found, page 1 of 2
Plastic waste-derived carbon nanotubes: Influence of growth catalyst and cataly...
Roman, Fernanda; Silva, Adriano S.; Díaz de Tuesta, Jose Luis; Baldo, Arthur Pietrobon; Lopes, Jéssica Paula Marim; Gonçalves, Giane; Pereira, Ana I.Low-density polyethylene (LDPE) was used in this work to grow carbon nanotubes (CNTs) by chemical vapor deposition (CVD) over catalysts based on Ni, Fe and Al, synthesized either by co-precipitation (C) or wet impregnation (I) methods, with CNT yields in the range of 16–33 %. The morphology of the CNTs was directly influenced by the route used for the CVD catalyst synthesis, with co-precipitation-derived CVD ca...
Plastic waste-derived carbon nanotubes: Influence of growth catalyst and cataly...
Roman, Fernanda; Silva, Adriano S.; Tuesta, Jose L. Diaz de; Baldo, Arthur P.; Lopes, Jessica P.M.; Gonçalves, Giane; Pereira, Ana I.; Praça, PauloLow-density polyethylene (LDPE) was used in this work to grow carbon nanotubes (CNTs) by chemical vapor deposition (CVD) over catalysts based on Ni, Fe and Al, synthesized either by co-precipitation (C) or wet impregnation (I) methods, with CNT yields in the range of 16–33 %. The morphology of the CNTs was directly influenced by the route used for the CVD catalyst synthesis, with co-precipitation-derived CVD ca...
Production and characterization of biodiesel obtained by transesterification ca...
Baú, Ana; Gonçalves, Giane; Ribeiro, António E.; Queiroz, Ana; Brito, PauloBiodiesel is a fuel that shows an increasing demand as a promising alternative to petroleum-based fuels. Biodiesel is produced by means of esterification or transesterification reactions, from renewable raw materials, as animal and vegetable oils and fats. The biodiesel generated by the traditional method of production proved that is economically and environmentally disadvantageous, due to this, in its producti...
Diffusion equations and different spatial fractional derivatives
Duarte, Alexandre F. B.; Pereira, Jessica de M. Gatti; Lenzi, Marcelo Kaminski; Gonçalves, Giane; Rossato, Roberto; Lenzi, Ervin KaminskiWe investigate for the diffusion equation the differences manifested by the solutions when three different types of spatial differential operators of noninteger (or fractional) order are considered for a limited and unlimited region. In all cases, we verify an anomalous spreading of the system, which can be connected to a rich class of anomalous diffusion processes.
Morphology change in nematic membranes induced by defects
Taniguchi, Maiara Mitiko; Zola, Fernanda Cavicchioli; Guimarães, Veridiana Garcia; Gonçalves, Giane; Rossato, Roberto; Zola, Rafael SoaresThe cell membrane is one of the most important structures of living organisms. This is due to the many functions attributed to it such as permeable selectivity, protection, anchoring to the cytoskeleton and so many others. Any change in the shape of the cell membrane may affect directly the properties and abilities. In this article, we study how defects in the liquid crystalline organization of a membrane can c...
Nonlinear diffusion equation, solutions and anomalous diffusion - DOI: 10.4025/...
Badini, Renata Ferreira Colli; Gonçalves, Giane; Lenzi, Marcelo Kaminski; Santos, Onélia Aparecida Andreo dos; Jorge, Luiz Mário de MatosThis work aimed to investigate a nonlinear diffusion equation by considering the presence of a time dependent diffusion coefficient, convective and absorbent terms. The nonlinear terms present in the diffusion equation are consequence of employing a nonlinear generalization of Darcy’s law or a nonlinear absorbent term, which may be related to a reaction diffusion process. Particularly, we will obtain new classe...
Nonlinear fractional diffusion equation: exact solutions - DOI: 10.4025/actasci...
Gonçalves, Giane; Lenzi, Marcelo Kaminski; Lenzi, Ervin Kaminski; Antonio, Fernando José; Schot, AlexandreWe devote this work to investigate the solutions of a generalized diffusion equation which contains spatial fractional derivatives and nonlinear terms. The presence of external forces and absorbent terms is also considered. The solutions found here can have a compact or long tail behavior. Particularly in the last case in the asymptotic limit, we relate these solutions to the Lévy or Tsallis distributions. In a...
Performance of an integral methane reforming fixed bed reactor packed with an i...
Francisquini, Douglas Rodrigues; Gonçalves, Giane; Santos, Onélia Aparecida Andreo dos; Jorge, Luiz Mario de MatosThe present work has the objective to evaluate the catalytic activity and the temperature profile inside an integral steam reforming fixed bed reactor heated by an electrical furnace and packed with an industrial catalyst. Nine temperature measures were made along nine axial positions and the composition of the products reaction were evaluated by gas chromatography. The experimental conditions were: temperature...
Anomalous diffusion and fractional diffusion equations
Gonçalves, Giane; Lenzi, Marcelo Kaminski; Moraes, Luciana de Souza; Lenzi, Ervin Kaminski; Andrade, Marcelo Freitas deIn this work we investigate the anomalous diffusion equations, usually applied to describe the anomalous diffusion, which employ fractional derivatives for the time or the spatial variables. In particular, we obtain exact solutions by taking a generic initial condition into account and developing a perturbation theory to investigate complex situations. We also verify that the fractional derivatives, when applie...
Ni-SiO2 and Ni-Al2O3 sol-gel catalysts applied to methane reforming with CO2 - ...
Gonçalves, Giane; Martinelli, Fernando Quilice; Costa, Creusa Maieru Macedo; Jorge, Luiz Mario de Matos; Santos, Onélia Aparecida Andreo dosThe dry reforming reaction of methane comes as a promising process of syngas and hydrogen. Nickel catalysts on Al2O3 and SiO2 were synthesized by sol-gel method, with metalic load of 8% weight. The catalysts were characterized by temperature programmed reduction (TPR), termogravimetry analysis (TGA) and specific surface area measurements (BET). The dry reforming reaction was performed in a micro reactor packed ...