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Artigo 2-[(4-Chlorophenyl)selanyl]-3,4-dihydro-2H-benzo[h]chromene-5,6-dione: Crystal structure and Hirshfeld analysis(2017) Zukerman-Schpector J.; Prado K.E.; Name L.L.; Cella R.; Jotani M.M.; Tiekink E.R.T.© 2017.The title organoselenium compound, C19H13ClO3Se {systematic name: 2-[(4-chlorophenyl)selanyl]-2H,3H,4H,5H,6H-naphtho[1,2-b]pyran-5,6-dione}, has the substituted 2-pyranyl ring in a half-chair conformation with the methylene-C atom bound to the methine-C atom being the flap atom. The dihedral angle between the two aromatic regions of the molecule is 9.96 (9)° and indicates a step-like conformation. An intramolecular Se⋯O interaction of 2.8122 (13) Å is noted. In the crystal, φ-φ contacts between naphthyl rings [inter-centroid distance = 3.7213 (12) Å] and between naphthyl and chlorobenzene rings [inter-centroid distance = 3.7715 (13) Å], along with C-Cl⋯φ(chlorobenzene) contacts, lead to supramolecular layers parallel to the ab plane, which are connected into a three-dimensional architecture via methylene-C-H⋯O(carbonyl) interactions. The contributions of these and other weak contacts to the Hirshfeld surface is described.Artigo A concise and systematic study of the hydrothermal synthesis of Si-MCM-48: Structural aspects and mechanical stability(2021-02-05) MARTINS, E. G.; BESSA, B. G.; SILVA, S. C.; GOMES, E. L; Rodrigo Condotta© 2021 Elsevier Inc.The structural collapse of mesoporous molecular sieve Si-MCM-48 by mechanical compression was investigated. Samples were synthesized by modifying temperature and time of a hydrothermal synthesis, according to a 32 experiment design. In this way, flexibility of the synthesis method was evaluated. Structural and textural characteristics were investigated using X-ray diffraction, nitrogen physisorption, and scanning and transmission electronic microscopies. As a consequence of the increase in applied pressure, different behavior was observed in the average wall thickness of samples related to the porous organization of the solid. The collapse of interparticular macropores caused a greater increase in thickness at low compression pressures, while the intraparticular mesopores, supported by the silica walls, supported greater compression. The macropores collapsed by mechanical compression at pressures as low as 60 MPa, while mesoporous ones exhibited reasonable resistance up to 200 MPa. Samples synthesized with high temperatures and long reaction times presented better mechanical resistance due to the favorable kinetics of silica condensation on the walls and, thus, are more interesting for applications in catalysis or adsorption.Artigo A new framework to quantify thewetting behaviour of carbonate rock surfaces based on the relationship between zeta potential and contact angle(2020-01-05) GOMARI, S. R.; AMROUCHE, F.; Ronaldo Santos; GREENWELL, H. C.; CUBILLAS, P.© 2020 by the authors.This study introduces a new framework to quantify the wettability of powdered carbonate rock from existing correlations between zeta potential and contact angle. The new framework has the potential to be faster and cheaper than conventional approaches and could increase confidence in surface wetting quantification, since the results are insensitive to the inherent heterogeneity of rock surfaces. The obtained results from experiments were used to develop a set of equations for determining the carbonate rock contact angle from streaming potential data. The equations were validated for the evaluation of changes in the wettability of carbonate rock using different stearic acid oily solutions. The contact angles calculated from the proposed equations were then compared with measured values on the calcite surface. The results show that the proposed framework was able to quantify the wettability of carbonate rock with an acceptable range of error of about 4%-14%.Artigo A proposed predictive methodology for the evaluation of caking effect on different types of commercial sugars Proposição de uma metodologia preditiva para avaliação do efeito caking em diferentes tipos de açúcares comerciais(2020-03-23) Rodrigo Condotta; SILVA, P. M. DA© 2020 Instituto de Tecnologia de Alimentos - ITAL. All rights reserved.This paper presents preliminary results of an alternative experimental methodology under development to predict the caking effect often observed in bulk solids after time storage. This methodology is based on 1) the principle that the particle is sheared after the shear stress overcome a maximum value; 2) the maximum shear stress depends on the particles physical properties and their chemical nature; 3) Prorating is a well-known and often used empirical procedure to minimize the scatter at shear tests; and 4) that the static friction coefficient depends on particle-particle contact time and could be described by the phenomenological state-and-rate model formulated by Dieterich, Rice, and Ruina. The proposed methodology aims to evaluate the increasing of the static coefficient of friction with rest time, through “stop-and-go” shear experiments and according to Dieterich, Rice and Ruina model. Finally, the increase in shear stress with time is used to extrapolate the instantaneous yield locus into a predicted time yield locus, using the prorating technique We tested four types of commercial sugar and the results of time yield locus, obtained from experiments, have seemed similar to those predicted using the proposed methodology. We obtained satisfactory results for the short rest times tested in this preliminary study, which could be extended to long periods.Artigo Alkyd resin synthesis by enzymatic alcoholysis(2019) de Carvalho R.K.C.; Ortega F.S.; Morandim-Giannetti A.A.© 2019, Iran Polymer and Petrochemical Institute.The synthesis of an alkyd resin through an enzymatic alcoholysis provided by Novozym 435 was analyzed in this study. The alcoholyses were performed in different enzyme concentrations (2.63, 4.00, 6.00, 8.00, and 9.36%, based on oil’s mass), oil/glycerin ratios (1.68, 2.50, 3.50, 4.50, and 5.18 oil mol/glycerin mol), at temperatures (33.18, 40.00, 50.00, 60.00, and 66.82 °C) to determine the best reaction conditions for obtaining the highest percentage of monoacylglycerides and diacylglycerides [glycerin/vegetal oil ratio of 1:3.5 (mol/mol), at temperature of 56.73 °C, and 9.36% enzyme concentration based on oil’s mass (w/w)]. It was verified that 2 h was the ideal reaction time. Under the best alcoholysis condition, the alkyd resin was produced using phthalic anhydride and the product presented similar characteristics as the current resin produced by a chemical catalyst in the industrial process (final viscosity = Y2, solid content = 44.00%, and IA ≤ 12). 1H NMR and FTIR analyses confirmed the formation of an alkyd resin as they showed the presence of characteristic signals of the final product. The re-usability of the enzyme was investigated, and significant results were observed in the reaction after five cycles (by activity reduction of 6%) showing the viability of applying enzymatic steps in industrial procedures to produce resins in the future, once the application of enzymes also reduced the level of toxicity in the processes.Artigo An adaptive fuzzy feedforward-feedback control system applied to a saccharification process(2018) Fonseca R.R.; Sencio R.R.; Franco I.C.; Da Silva F.V.© 2018 Walter de Gruyter GmbH, Berlin/Boston.In industrial bioprocess control, disturbance sources typically influences process variable regulation. These disturbances may reduce a system control performance or even affect the final bioproduct quality. Therefore, feedforward control is desired because it anticipates the effects caused by these disturbances in an attempt to keep the process variable at the setpoint value. However, designing a feedforward control law requires process modeling, which can be a tough task when dealing with bioprocesses that are intrinsically nonlinear and multivariable systems. Thus, an adaptive feedforward control law or other advanced control system is needed for satisfactory disturbance rejection. For this reason, a general fuzzy feedforward control system is proposed in this paper to replace the classical feedforward control, making it easier to implement the feedforward control action by avoiding nonlinear and multivariable process modeling. The adaptive fuzzy feedforward-feedback (A4FB) system was applied to a product concentration control loop in an enzymatic reactor, to reject disturbances caused by variations in the substrate and enzymatic solutions feed concentration. The results showed that the A4FB controller rejected much more disturbance effects than classical feedforward control law, demonstrating its advantage, supported by not only its simple implementation, but also its improved disturbance rejection.Artigo de revisão An overview of heavy oil properties and its recovery and transportation methods(2014-07-01) SANTOS, R. G.; LOH, W.; BANNWART, A. C.; TREVISAN, O. V.© 2014, Assoc. Brasiliera de Eng. Quimica / Braz. Soc. Chem. Eng. All rights reserved.Unconventional oils - mainly heavy oils, extra heavy oils and bitumens - represent a significant share of the total oil world reserves. Oil companies have expressed interest in unconventional oil as alternative resources for the energy supply. These resources are composed usually of viscous oils and, for this reason, their use requires additional efforts to guarantee the viability of the oil recovery from the reservoir and its subsequent transportation to production wells and to ports and refineries. This review describes the main properties of high-viscosity crude oils, as well as compares traditional and emergent methods for their recovery and transportation. The main characteristics of viscous oils are discussed to highlight the oil properties that affect their flowability in the processes of recovery and pipeline transportation. Chemical composition is the starting point for the oil characterization and it has major impact on other properties, including key properties for their dynamics, such as density and viscosity. Next, enhanced oil recovery (EOR) methods are presented, followed by a discussion about pipeline and transportation methods. In addition, the main challenges to achieve viable recovery and transportation of unconventional oils are compared for the different alternatives proposed. The work is especially focused on the heavy oils, while other hydrocarbon solid sources, such as oil sands and shale oil, are outside of the scope of this review.Artigo ANÁLISE DE RISCOS DO PROCESSO DE PRODUÇÃO DE FENOL E ACETONA A PARTIR DO BENZENO E PROPENO(2018) KABBACH, CLARA BOTARELLI; LUIS, DANIELA DENLESCHI; SOALHEIRO, GABRIELA C.; TAVARES, JOSÉ EDUARDO A.; LEGGIERI, TOMÁS FAGUNDES; CONDOTTA, Rodrigo; MARIN, Maristhela Passoni de AraújoArtigo ANÁLISE DE RISCOS E CONSEQUÊNCIAS EM UMA USINA SUCROALCOOLEIRA(2017) MARIN, Maristhela Passoni de Araújo; DE MELO, GABRIELA MESSIAS; DE PAULO, GUILHERME BARBOSA HENKE; LABATE, LUIZ FERNANDO MACHADO; MIRANDA, THIAGO BACO; SCHINCARIOL, VANESSAArtigo Análise e Otimização das Condições Operacionais de um Reator de Leito Fixo na Síntese de Fischer-Tropsch(2016) DELBIANCO, J. V. T.; OLIVEIRA, L. F. M.; VILAS BOAS, L.; NOVAZZI, Luis FernandoArtigo ANÁLISE ESTATÍSTICA APLICADA AOS PARÂMETROS DE SÍNTESE DE FAUJASITA Na-X(2017) CASTRO, MAYARA DOS SANTOS; FANTIM, WELLINA MASSASSI; CONDOTTA, Rodrigo; GOMES, ELIEZER LADEIA; POCO, Joao Guilherme RochaArtigo ANÁLISE TÉCNICA DA PRODUÇÃO DO BIODIESEL A PARTIR DO ÓLEO DE FRITURA RESIDUAL(2018) DE ROSSI, GUSTAVO ZANETTI; BORGES, IVAN ROCHA; PEREGO, THAYANE FERREIRA; TOLEDO, VICTOR DALLACQUA MADEIRA; FERREIRA, Luis Fernando PeffiArtigo ANÁLISE TÉCNICA E ECONÔMICA DE FONTES DE ENERGIA RENOVÁVEIS(2018) DE OLIVEIRA, ANA PAULA MOREIRA; FUGANHOLI, NICOLA SGRIGNOLI; CUNHA, PEDRO HENRIQUE DE SOUZA; BARELLI, VIVIAN APARECIDA; BUNEL, MAXIME PHILIPPE MICHEL; NOVAZZI, Luis FernandoArtigo Analysis of the effects of neuro-fuzzy control configuration parameters on PH neutralization process(2018) Mazzali D.G.Z.; Franco I.C.; Silva F.V.© 2018 Walter de Gruyter GmbH, Berlin/Boston.The pH neutralization process is typical in chemical, biological and petrochemical industries. One of the major challenges to control it is to understand its nonlinearities and that requires several fine adjustments from conventional controls. Artificial Intelligence has been used to study these nonlinearities; one of them is Neuro-Fuzzy Logic, which was investigated in this work to develop controls dedicated to this process. These controls are formed by logical structures and may be adjusted to different configurations. In practical applications, it is highly important to adapt control parameters based on artificial intelligence to obtain better performance. The present work studied the effect of different configurations of a neuro-fuzzy control on the performance of a regulatory control to pH neutralization process by means of a virtual plant developed in both Indusoft and Matlab environments. For both variables, pH and reactor level control, membership function (MF) = [Gaussian], method "OR" = [probabilistic], method "E" = [product], type of MF output = [linear] and the optimization method = [hybrid], have improved control performance, which confirms the importance of configuration choices in neuro-fuzzy control adjustments. Moreover, the most determining factor in NFC performance is the types of membership functions.Artigo APLICAÇÃO DA TEORIA PRIGOGINE-FLORY-PATTERSON AO VOLUME MOLAR EXCESSO DE SOLUÇÕES LÍQUIDAS BINÁRIAS DE {METIL TERC BUTIL ÉTER (MTBE) + ALCOÓIS} A DIFERENTES TEMPERATURAS E PRESSÃO ATMOSFÉRICA(2018) HOGA, HELOISA EMI; TORRES, Ricardo BelchiorArtigo Aplicação do peróxido de hidrogênio como reforço da deslignificação do bagaço de cana-de-açúcar(2012) Higa, F. G. R.; GIANNETTI, Andreia de Araujo Morandim; TAMBOURGI, E. B.Artigo Aplicação do Processo Fenton para Descontaminação de Hidrocarbonetos Aromáticos em Água(2016) ZANINI, F. A.; SANTOS, F. A. R.; MATSUMURA, L. A.; NOVAZZI, Luis Fernando; FRANCISCO, M. T.; PAIVA, T. M.Artigo Attainment and characterization of carboxymethyl chitosan hydrogels by enzymatic cross-linking(2019) Morandim-Giannetti A.A.; Wecchi P.O.; Silverio P.A.; Carlstron R.; Bersanetti P.A.© 2019, Akadémiai Kiadó, Budapest, Hungary.In this study, carboxymethyl chitosan hydrogels (CMCH) cross-linked with catechin in the presence of laccase (CMCH-C-L) were obtained. The synthesis and characterization of CMCH were carried out from chitosan (CH) and its cross-linking with catechin (C) in the presence of laccase (L). DSC, ATR-FTIR, and rheological analyses of the CMCH solution and CMCH-C-L hydrogel were carried out. Three main thermal events were observed in the DSC characterization with temperatures and enthalpies related to each event for CMCH: 167.2 °C/+ 523.3 J g−1, 269.1 °C/− 35.0 J g−1, and 333.3 °C/− 17.6 J g−1, possibly referring to these processes: polymerization, breaking of electrostatic interactions, and decomposition of the material, respectively. The CMCH-C-L hydrogel presented values of 165.2 °C/+ 376.6 J g−1, 266.7 °C/− 47.8 J g−1, and 333.3 °C/− 31.5 J g−1. Conversely, the chitosan presented only one thermal event of decomposition at 302.5 °C and enthalpy of − 258.5 J g−1. Rheological properties of the hydrogels (viscosities, consistency values, and flow indices) showed non-Newtonian pseudoplastic rheological behavior and that the viscosity increased approximately 150% after the reaction (134.25 mPa s for CMCH and 342.85 mPa s in CMCH-C-L) confirming the formation of cross-links after the addition of catechin and laccase. Morphological analyses of CMCH and CMCH-C-L films via SEM showed the modification of the material after the reaction with the catechin in the presence of laccase and corroborated with the results, confirming the presence of cross-links.Artigo Attainment of cellulose acetate from coir fiber submitted to pretreatment with IL n-butylammonium acetate(2019) de Andrade Neto J.C.; de Almeida A.C.; dos Santos Machado C.; Coelho D.O.; Mourad N.; Teixeira N.S.; Pereira G.J.; Morandim-Giannetti A.A.© 2019, Iran Polymer and Petrochemical Institute.Cellulose acetate was obtained from the coir fiber submitted to the treatment with the IL. The coir fiber was initially subjected to treatment with the n-butylammonium acetate IL (CFIL) and subsequent bleaching (CFILB). By analyzing the CFILB, it was possible to observe a delignification of 6.10% in relation to the natural material and an 8.1% increase in the concentration of cellulose. The results from SEM, XRD, and FTIR-ART confirm the modifications in the fiber. After characterizing the treated coir fiber and obtaining the cellulose acetate, analyses by NMR confirmed its regeneration with a degree of substitution at 2.92. FTIR analyses corroborate with the obtained data, verifying the presence of the main adsorption bands. The XRD analysis of cellulose acetate shows peaks at 8.5° regarding the randomness after the acetylation of cellulose, as well as peaks between 18° and 22.5° regarding the packing of carbon atoms due to the Van der Waals forces, which confirm the production of cellulose acetate. The thermal analysis shows that decomposition events occurred in two stages, indicating the thermal decomposition of the remaining cellulose, which did not undergo acetylation, and attribution to its thermal degradation.Artigo de evento Automation and Control of a Dissolved Air Flotation Pilot Plant(2017) Fonseca R.R.; Thompson J.P.; Franco I.C.; da Silva F.V.© 2017Turbidity is an important process variable on water treatment processes for safeguard health requirements, and dissolved air flotation (DAF) is a physical treatment that allows water turbidity reduction by floating particles dispersed on water. Hence, a DAF pilot plant was assembled and automated using supervisory control and data acquisition (SCADA), open platform of communication protocol (OPC), signal filters and Ethernet to test two possible strategies for water turbidity control. The results indicated that manipulating recycle ratio by needle valve opening has advantages on DAF control.