5,003 research outputs found
Development Of A Computational Tool For Simulating Falling Film Molecular Design
No full textIn a previous work, a software named DISMOL was developed in order to simulate molecular distillation (MD). However, due to the restricted access to this tool, and to the importance of having a computational tool available for future investigations of operational policies in oil refinery, in the present work, it is proposed the development of a general procedure for this highly specific process in the commercial simulator Aspen Plus®. Since no single unit operation is available in the commercial simulator that can appropriately simulate a falling film distillator, the proposal, in a preliminary approach, makes use of a sequence of flash vessels corrected with process efficiency, in order to accomplish the task of MD simulation. Experimental data of a binary system distillated in a falling film molecular distillator are used for the validation of the developed procedure. The results indicate the potential of the proposed procedure to represent a MD equipment for the system evaluated, making possible the study of different operational policies in conducting this high vacuum distillation operation for high-value products, such as the derived from oil refining. © 2009 Elsevier B.V. All rights reserved.26743748Erciyes, A.T., Ishikawa, H., Inuzuka, M., Hiraoka, S., Mori, H., Yamada, I., (1987) I. Chem. E. Symposium Series, 1, pp. A359Hernández, J.A.B., Linan, L.Z., Jardin, A., Maciel, M.R.W., Filho, R.M., Oliveira, L.C.M., Rio Oil & Gás Expo and Conference, Rio de Janeiro, Brazil (2008) IBP2712_, 8Rocha, E.R.L., Maciel, M.R.W., Filho, R.M., Batistella, C.B., Oliveira, L.C.M., Rio Oil & Gás Expo and Conference, Rio de Janeiro, Brazil (2008) IBP2724_, 8Rocha, R.S., Maciel, M.R.W., Filho, R.M., Batistella, C.B., Oliveira, L.C.M., Rio Oil & Gás Expo and Conference, Rio de Janeiro, Brazil (2008) IBP2730_, 8Batistella, C.B., Maciel, M.R.W., (1996) Computers Chem. Engng., 20, pp. S19Lutisan, J., Cvengros, J., Micoslav, M., (2002) Chemical Engeneering Journal, 85, p. 225Hickman, K.C.D., (1943) A Review. Chem. Rev., 34, p. 51Lutisan, J., Cvengros, J., Micoslav, M., (2000) Chemical Engeneering Journal, 78, p. 6
Detailed Deterministic Dynamic Models For Computer Aided Design Of Multiphase Slurry Catalytic Reactor
No full textThe non-isothermal dynamic models of the three-phase slurry catalytic reactor with appropriate solution procedure were developed in this work. The models consist on mass and heat balance equations for the catalyst particles as well as for the bulk phases of gas and liquid, and momentum balance equations for the fluid phase. The models were used to describe the dynamic behaviour of a hydrogenation of phenol in catalyst of Ni-Rhaney, producing cyclohexanol and cyclohexane (undesired product). These heterogeneous models include the heat exchange through the jacket of the reactor, evaluates the effect of the phase change of the reacting medium (flash) and the cooling fluid, as well as the variation of the physical properties and the coefficients of heat and mass transfer. The proposed model has shown to be able to predict the main characteristics of the dynamic behaviour of reactor. © 2004 Elsevier B.V. All rights reserved.18C823828Corrêa, E.J., Cotta, R.M., Improved Lumped-Differential Formulations of Transient Heat Conduction Problems (1994) III Congress of Mechanical, , presented at, Engineering on North-NortheastCoussemant, F., Jungers, J.C., Cinetique de l'Hydrogénation Catalytique des Phénols (1950) Bull. Sec. Chim. Belg., 59, pp. 295-326Maciel Filho, R., Modelling and Control of Multitubular Reactors (1989) Ph.D. Thesis, , University of Leeds, PA, BrazilVasco de Toledo, E.C., Wolf Maciel, M.R., Maciel Filho, R., Dynamic Modelling of a Three-Phase Catalytic Slurry Reactor (2001) Chemical Engineering Science, 56 (Iss 21-22). , 00215Vasco de Toledo, E.C., Maciel Filho, R., Development of a Dynamic Model for a Three-Phase Catalytic Slurry Reactor with Change of Phase of the Reacting Medium and the Cooling Fluid (2002) 17th International Symposium on Chemical Reaction Engineering, ISCRE 17, , August, 25-28, Hong Kong, Chin
A New Computational Tool For Falling Film Molecular Distillation Performance Prediction
No full textIn a previous work, a software named DISMOL, was developed in order to simulate molecular distillation. However, due to the restricted access to this tool and the easiness to make use of data bank and physical properties, in the present work, it is proposed the development of general procedure for this highly specific process in the commercial simulator Aspen Plus®, Since no single unit operation is available in the commercial simulator that can appropriately simulate a falling film molecular distillator (MD), the proposal, in a preliminary approach makes use of a sequence of flash vessels in order to accomplish the task of MD simulation. Experimental data of a binary system distillated in a MD are used for the validation of the developed tool. The results indicate the high potential of this tool in representing a MD equipment, making possible the evaluation of different operational policies in conducting this high vacuum distillation to achieve products with the desired quality and properties. The development of the proposed computational tool is an important step for the investigations of operational policies for MD application in oil refining since no industrial data of such equipment is available. © 2009 Elsevier B.V. All rights reserved.27C19051910Erciyes, A.T., Ishikawa, H., Inuzuka, M., Hiraoka, S., Mori, H., Yamada, I., (1987) I. Chem. E. Symposium Series, 1, pp. A359Hernández, J.A.B., Linan, L.Z., Jardin, A., Maciel, M.R.W., Filho, R.M., Oliveira, L.C.M., (2008) Rio Oil & Gás Expo and Conference, , Rio de Janeiro, Brazil, IBP2712-08Rocha, E.R.L., Maciel, M.R.W., Filho, R.M., Batistella, C.B., Oliveira, L.C.M., (2008) Rio Oil & Gás Expo and Conference, , Rio de Janeiro, Brazil, IBP2724-08Rocha, R.S., Maciel, M.R.W., Filho, R.M., Batistella, C.B., Oliveira, L.C.M., (2008) Rio Oil & Gás Expo and Conference, , Rio de Janeiro, Brazil, IBP2730-08Batistella, C.B., Maciel, M.R.W., (1996) Computers Chem. Engng., 20, pp. S19Lutisan, J., Cvengros, J., Micoslav, M., (2002) Chemical Engeneering Journal, 85, p. 225Hickman, K.C.D., (1943) A Review. Chem. Rev., 34, p. 51Lutisan, J., Cvengros, J., Micoslav, M., (2000) Chemical Engeneering Journal, 78, p. 61P.S.D. Santos, Sc. D. These, Laboratory of Separation Process Development, School of Chemical Engeneering, State University of Campinas, São Paulo, Brasil, 200
R.M. Simmons presentation, Rena Smart book review
No full textR.M. Simmons of the Gospel Music Workshop of America gives a presentation on the African influence in the African American religious experience. He explains how African slaves brought to America their concept of music (utilitarian concept of music). Simmons further discusses the fusion between the utilitarian concept and the Western concept of religion resulting in spirituals. He also describes hymn categories in early forms of formal African American worship experiences. Simmons takes questions from the audience among which is Dr. Riggins Earl Jr. Video concludes with a book review on Christian Theology and Ethics by Rena Smart.The Atlanta University Center Robert W. Woodruff Library acknowledges the generous support of the National Endowment for Humanities - Humanities Collections and Reference Resources Implementation Project Grant in supporting the processing and digitization of a number of its major archival collections as part of the project: Spreading the Word: Expanding Access to African American Religious Archival Collections at the Atlanta University Center Robert W. Woodruff Library.</em
Multi-feed Hdt Reactor High Performance Operation
No full textThe HDS, HDN, hydrodeoxygenation, hydrocracking, and saturative hydrogenation of middle distillates are studied. An adiabatic diesel hydrotreating trickle bed reactor packed is simulated by pseudo-homogeneous and heterogeneous models to check up the behavior of this specific reaction system. An alternative design is proposed through the subdivision of the catalytic bed with middle addition of a quench stream to improve the operational flexibility in the treating of different types of feedstocks. The conversion profile of the sulfur is presented, where high conversion values can be observed. To avoid high values of temperature, the solution used in petroleum refineries is to introduce lateral feedings of hydrogen (quench) along of the reactor length. This is an abstract of a paper presented the 18th World Petroleum Congress (Johannesburg, South Africa 9/25-29/2006).2006Deckwer, W.D., (1992) Bubble Column Reactors, , John Wiley and Sons, New YorkGianetto, A., Silveston, P.L., (1986) Multiphase Chemical Reactors: Theory, Design, Scale-up, , Hemisphere Publishing Corporation, WashingtonCotta, R.M., Wolf-Maciel, M.R., Maciel Filho, R., A Cape of HDT industrial reactor for middle distillates (2000) Comp. Chem. Eng, 24, p. 1731Julcour, C., Stbber, F., Le Lann, J.M., Wilhelm, A.M., Delmas, H., Dynamics of a Three-Phase Upflow Fixed-Bed Catalytic Reactor (1999) Chemical Engineering Science, 54, pp. 2391-2400Lange, R., Gutsche, R., Hanika, J., Forced Periodic of a Trickle-Bed Reactor (1999) Chemical Engineering Science, 54, pp. 2569-2573Ramachandran, P.A., Chaudhari, R.V., (1983) Three-Phase Catalytic Reactors, , Gordon and Breach Science Publisher, New YorkSalmi, T., Worna, J., Toppinen, S., Runnholm, M., Mikkola, J.-P., Dynamic Modelling of Catalytic Three-Phase Reactors for Hydrogenation and Oxidation Processes (2000) Brazilian Journal of Chemical Engineering, 17 (4-7), pp. 1023-1034Tarhan, M.O., (1983) Catalytic Reactor Design, , New York: McGraw-Hill, IncVasco de Toledo, E.C., Santana, P.L., Wolf Maciel, M.R., Maciel Filho, R., Dynamic Modelling of a Three-Phase Catalytic Slurry Reactor (2001) Chem. Eng. Sci, 56, p. 6055Vasco de Toledo, E.C., Maciel Filho, R., Development of a Dynamic Model for a Three-Phase Catalytic Slurry Reactor with Change of Phase of the Reacting Medium and the Cooling Fluid (2002) 17th International Symposium on Chemical Reaction Engineering, ISCRE 17, , August 25-28, Hong Kong, ChinaWarna, J., Salmi, T., Dynamic Modeling of Catalytic Three Phase Reactors (1996) Computers Chem. Engng, 20 (1), pp. 39-4
Maps of soil organic carbon stocks in Brazil
No full textThis database was created by Gustavo Vieira Veloso and Lucas Carvalho Gomes 04/06/2022.
Contact: [email protected] and [email protected]
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Maps of soil organic carbon (SOC) stocks in Brazil of the article: "Modeling and mapping soil organic carbon stocks in Brazil" (doi: 10.1016/j.geoderma.2019.01.007)
The dataset is composed of five folders of SOC stocks maps at the standard depths (0–5, 5–15, 15–30, 30–60, and 60–100 cm). The maps are in Geotif format (EPSG 102015) with a spatial resolution of approximately 1 km and include the mean SOC stocks, standard deviation (SD), coefficient of variation (CV), 0.05 and 0.95 quantiles.
The maps are free to use and please cite also the article:
Gomes, L.C., Faria, R.M., de Souza, E., Veloso, G.V., Schaefer, C.E.G., & Fernandes Filho, E.I. (2019). Modeling and mapping soil organic carbon stocks in Brazil. Geoderma, 340, 337-350
A Multitubular Reactor For Obtention Of Acetaldehyde By Oxidation Of Ethyl Alcohol
No full textIn this work an alternative process for the obtention of acetaldehyde is presented. It is based on the oxidation of ethyl alcohol over commercial Fe-Mo catalyst. Experimental kinetic data, obtained in an integral reactor, were interpreted by a Temkin's type mechanism, although it is possible to treat the data by a known mechanism similar to the oxidation of methanol to formaldehyde. A new multitubular reactor is then proposed with the obtained rate equation. It is baffled but windowless, so that better temperature control is achieved when compared with conventional reactors. The process considered here exhibits better performance than the best known processes in terms of higher conversions, stability and yield in acetaldehyde. © 1992.479-1125712576Day, Oxidation of ethyl-alcohol (1931) Journal of Physical Chemistry, 35, pp. 9272-9279Dente, Poppi, Pasquon, Cinetica dell'ossidazione del metanolo a formaldeide con catalizzatore a base di ossidi di Fe e Mo (1964) La Chimica e I'Industria, 46 (11), pp. 1326-1336Domingues, Modelagem do Processo de Oxidação do Etanol a Acetaldeído (1992) Tese de Mestrado, UNICAMP, FEQ/DPQ/LOPCA, , Campinas, São Paulo, Brasil, in preparationFroment, Bischoff, (1990) Chemical Reactor Analysis and Design, , 2nd edition, John Wiley & SonsMaciel Filho, Oxidação Catalítica de Etanol a Acetaldeído sobre Catalisador de Ferro Molibdênio (1985) Tese de Mestrado 069/85, , UNICAMP, FEC/DEQ, Campinas, Sao Paulo, BrasilMaciel Filho, Modelling and Control of Multitubular Reactors (1989) PhD Thesis, , Department of Chemical Engineering, The University of Leeds, Leeds England, UKMaciel Filho, Domingues, Modelagem Detalhada de Reator de Leito Fixo para conversão de Etanol a Acetaldeído (1991) XIX ENEMP - Encontro Nacional Sobre escoamento em Meios porosos, , UNICAMP, Campinas, São Paulo, BrasilMcGreavy, Maciel Filho, Insights on Temperature sensor Location in Multitubular Reactors (1989) Computer Integrated Process Engineering, , Institution of Chemical Engineers, Leeds, EnglandMcGreavy, Maciel Filho, Dynamic Behaviour of Fixed Bed Catalytic Reactors (1989) IFAC-Symposium on Dynamics and Control of Chemical Reactors, Distillation Columns and batch Processes, , The NetherlandsMoura, Oxidação do Etanol a Acetaldeído sobre Catalisador de Cobre Oxidado (1984) Tese de Duotorado 04/84, , UNICAMP, FEC/DEM, Campinas, São Paulo, Brasi
Velocity-Gradient Probability Distribution Functions in a Lagrangian Model of Turbulence
No full textThe Recent Fluid Deformation Closure (RFDC) model of lagrangian turbulence is recast in path-integral language within the framework of the Martin-Siggia-Rose functional formalism. In order to derive analytical expressions for the velocity-gradient probability distribution functions (vgPDFs), we carry out noise renormalization in the low-frequency regime and find approximate extrema for the Martin-Siggia-Rose effective action. We verify, with the help of Monte Carlo simulations, that the vgPDFs so obtained yield a close description of the single-point statistical features implied by the original RFDC stochastic differential equations
Computer Design Of A New Predictive Adaptive Controller Coupling Neural Networks And Kalman Filter
No full text[No abstract available]9C639644(1995), Addison-Wesley Publishing Company Inc., Lyngby, DenmarkEnder, L., Maciel Filho, R., (2000) Computers & Chemical Engeneering, 24, pp. 937-943Hecht-Nielsen, R., (1989) IEEE Int. Conf. On Neural Networks San Diego, pp. 593-605Goodwin, G.C., Sin, K.S., (1984) Adaptive filtering, Prediction and control, , Prentice-Hall, Englewood CliffsRodrigues, J.A.D., Maciel Filho, R., (1996) Chemical Engineering Science June, v51 (111), pp. 2859-2864. , ptBScheffer, R., Maciel Filho, R., Application of Neural Network and Other Learning Technologies in Process Engineering (2000) IEEE Int. Conf. On Neural Networks San Dieg
A psicologia na constituição do campo educacional brasileiro: a defesa de uma base científica da organização escolar
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Educação. Programa de Pós-Graduação em Educação.A presente pesquisa analisou como as idéias de Lourenço Filho referentes à Psicologia cientifica e materializadas no Teste ABC, contribuíram na constituição do campo educacional brasileiro, especialmente em relação à formação de professores e à organização da prática escolar. Para tanto, utilizamos o conceito de campo social de Pierre Bourdieu como fundamento para a análise da constituição do campo educacional brasileiro, bem como a contribuição dos diferentes campos científicos que nele intervieram, especialmente a Psicologia. Para a discussão do campo educacional brasileiro do inicio do século XX, optamos por considerar as instituições, os agentes, as práticas e os produtos que compõem esse campo. Destacamos Lourenço Filho como um agente central na constituição deste campo e na construção do campo cientifico da Psicologia. E entre suas produções debateremos os Testes ABC Para Verificação da Maturidade Necessária à Aprendizagem da Leitura e Escrita de Lourenço Filho (1934) que foram amplamente utilizados nas escolas públicas brasileiras para selecionar e classificar as crianças quanto a maturidade para a alfabetização, tendo em vista uma questão prática da educação: o elevado nível de repetência dos estudantes nos primeiros anos. Em Santa Catarina, no inicio século XX, os Testes ABC foram a única bibliografia comum na biblioteca de duas escolas de orientações teóricas e ideológicas distintas: o Instituto de Educação de Florianópolis, reduto dos renovadores liberais que veiculavam os conhecimentos da escola nova e o Colégio Coração de Jesus, escola de orientação católica. Os Testes ABC se afirmam como um importante produto do campo educacional, aceito por educadores de diferentes perspectivas teóricas e que representa um instrumento cientifico de organização da pratica pedagógica
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