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Fractionation of Green Coffee Oil by Molecular Distillation： Modeling and Simulation

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材料科学与工程（中英文A版） 2011年第2X期1卷 264-271页

作者： Melvin. Aroldo Duran rubens maciel filho Maria Regina Wolf maciel Laboratory of Oleochemical School of Chemical Technology Technological University of Pereira (UTP) Vereda la Julita CP 97Pereira Colombia Laboratory of Separation Process Development (LDPS) School of Chemical Engineering State University of Campinas(UNICAMP) CP 6066 Campinas SP Brazil

This work describes a non-equilibrium mathematical model and simulation procedures for the fractionation of green coffee oil via molecular distillation. The simulation results were in quantitative agreement with previously reported experimental. Green coffee oil makes up to 18% (w/w) of coffee beans (Coffea arabica). The main components of the coffee’s lipids are triglycerides accounting up to 80% w/w, diterpene fatty acid esters amounting up to 18% w/w. The large amount of diterpene fatty acids renders Green Coffee Oil unsuitable for use as an edible vegetable oil. The majority of these lipids can be found in liquid form inside the cells of the coffee beans. Fractionation of green coffee oil by molecular distillation offers an avenue to improve the quality of green coffee oil allowing its use in nutritional, cosmetic and pharmaceutical applications. Molecular distillation also provides a viable process to purify valuable products such as diterpene esters which has been reported to exhibit anticarcinogenic properties.

关键词：分子蒸馏技术仿真程序咖啡油分馏建模脂肪酸酯食用植物油二萜酯

Separation of Lactic Acid from Diluted Solution by Hybrid Short Path Evaporation and Reactive Distillation

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Journal of Chemistry and Chemical Engineering 2016年第6期10卷 271-276页

作者： Andrea Komesu Johnatt Allan Rocha de Oliveira Maria Regina Wolf maciel rubens maciel filho School of Chemical Engineering University of Campinas (UNICAMP) Box: 6066 Campinas-SP 13083970 Brazil Nutrition College Federal University of Para (UFPA) Belem-PA 66075110 Brazil

This work describes the separation and purification of lactic acid from diluted solution by HSPE （hybrid short path evaporation） and RD （reactive distillation） as coupled process. The results showed that it is pos... 详细信息

关键词： Lactic acid hybrid short path evaporation reactive distillation separation processes.

Modeling of Molecular Distillation Parameters： Case Study of Green Coffee Oil （Coffea arabica）

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Journal of Chemistry and Chemical Engineering 2011年第8期5卷 706-710页

作者： Melvin A. Duran Rmcon rubens maciel filho Maria R. W. maciel Laboratory of Oleochemical School of Chemical Technology Technological University of Pereira （UTP） Vereda la dulita Pereira CP 9 7 Colombia LOPCA-School of Chemical Engineering State University of Campinas （UNICAMP） CP 6066 Campinas SP Brazil LDPS-School of Chemical Engineering State University of Campinas （UNICAMP） CP 6066 Campinas SP Brazil

In principle, the free fatty acids, diterpene fatty acid esters and triglycerides from green coffee oil can be separated effectively, by a suitable separation process, due to the differences between molar mass and vapor pressures. In addition, in the case of component separation by molecular distillation, boiling point is replaced by evaporation rate at a given temperature. Several experiments and theoretical analyses have been carried out to identify the impact of important parameters （mean free path, evaporation rate, relative volatility and Knudsen number）, which determine the performance of these processes and degree of separation. In this work, a process development based on molecular distillation, for the enrichment of coffee diterpenes from green coffee oil is presented. The distillates were enriched in diterpene fatty acid esters and free fatty acids, while the residues were enriched in high molar mass triglycerides.

关键词： Diterpenes fatty acid esters Coffea arabica molecular distillation mean free path cafestol palmitate

Simulation of Molecular Distillation Process for Lactic Acid

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Journal of Chemistry and Chemical Engineering 2016年第5期10卷 230-234页

作者： Andrea Komesu Johnatt Allan Rocha de Oliveira Maria Regina Wolf maciel rubens maciel filho School of Chemical Engineering University of Campinas (UNICAMP) Box: 6066 Zip: 13083-970 Campinas-SP Brazil Nutrition College Federal University of Para(UFPA) Zip: 66075-110 Belem-PA Brazil

In this work, a procedure to simulate the MD （molecular distillation） process for lactic acid purification was developed. The simulation was carried out with the aid of the Aspen Plus Process Simulator. Flash vessel was used to represent the MD process since the software does not present this unit operation. The simulation results with efficiency factors were in agreement with previously reported experimental data.

关键词： Simulation lactic acid molecular distillation separation process.

Syngas Production from Crude Glycerol Using Pyrolysis

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Journal of Chemistry and Chemical Engineering 2011年第2期5卷 141-145页

作者： Ana Paula Gimenez Peres Nivea de Lima da Silva Mafia Regina Wolf maciel rubens maciel filho School of Chemical Engineering State University of Campinas （UNICAMP） Campinas-SP 13081-970 Brazil

Glycerol pyrolysis is carried out in a fixed bed reactor filled with alumina oxide. The packing material diameter was examined according to each one, but in general it was varied between 0.1-5.0 mm. The reaction temperature was varied in the range of 700-900 ℃, the reaction time from 10 to 50 min and flow rate of carrier gas from 0 to 60 mL/min. The process parameters listed above （factors） were used to evaluate the syngas production yield （response）. Also, syngas properties such as composition and heat value were evaluated. The experiments were carried out according to a 23 factorial design plus three central points. At last, a technical-economical analysis is carried out to examine the feasibility of syngas production from glycerol pyrolysis considering not only feedstock, catalyst and energy required costs but also conventional procedures used nowadays to produce syngas such as water electrolysis and natural gas catalytic reform.

关键词： Syngas crude glycerol pyrolysis

Application of Molecular Distillation Process to Extend the True Boiling Point Curve of Petroleum Residues 400 ℃ ＋

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Journal of Chemistry and Chemical Engineering 2011年第2期5卷 116-120页

作者： Erica Roberta Lovo da Rocha Melina Savioli Lopes Maria Regina Wolf maciel rubens maciel filho Cesar Benedito Batistella Lilian Carmem Medina Separation Process Development Laboratory （LDPS） School of Chemical Engineering University of Campinas Unicamp Campinas-SP 13083-970 Brazil Cenpes/Pdp/Tpap/Petrobras Brazil

True Boiling Point （TBP） distillation is one of the most common experimental techniques for determination of petroleum properties. The methods for performing TBP distillation experiments are described by ASTM D2892 and by ASTM D5236. However, these methods are established for petroleum fractions that reach temperatures up to 565 ~C. In this work, two petroleum residues were distilled in a falling film molecular distillation prototype and the data were used to obtain the extension of the TBP curve above a temperature of 565 ~C. It was possible to extend the TBP curve of both petroleum up to temperatures close to 700 ~C with consistency and continuity in comparison to the standard curve. In addition, an amount of raw material that was been treated as residue could be reused.

关键词： Molecular distillation true boiling point petroleum fraction.

Suiting Dynamic Models of Fixed-Bed Catalytic Reactors for Computer-Based Applications

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Engineering（科研） 2011年第7期3卷 778-785页

作者： Eduardo Coselli Vasco de Toledo Edvaldo Rodrigo Morais Delba Nisi Cosme Melo Adriano Pinto Mariano Joao F.C.A.Meyer rubens maciel filho Petrobras Paulínia Refinery(Replan)PaulíniaBrazil Laboratory of Optimization Design and Advanced ControlSchool of Chemical EngineeringUniversity of CampinasCampinasBrazil Institute of Mathematics Statisticsand Scientific ComputationUniversity of CampinasCampinasBrazil

This work investigated the applicability of heterogeneous and pseudo-homogeneous models to predict the dynamic behavior of a fixed-bed catalytic reactor. Some issues concerning the dynamic behavior of the system were discussed, such as the prediction of the inverse response phenomenon. The proposed models (Het- erogeneous I and II and Pseudo-homogeneous) were able to predict with qualitative similarity the main characteristics of the dynamic behavior of a fixed-bed catalytic reactor, including the inverse response. The computational time demanded for the solution of the heterogeneous models was 10 to 50% longer than in the case of the pseudo-homogeneous model, making the use of the former suitable for applications where computational time is not the major restriction (off-line applications). On the other hand, when on-line applications are required, the simplified model (Pseudo-homogeneous model) showed to be a good alternative because this model was able to predict (qualitatively) the dynamics of the reactor using a faster and easier numerical solution.

关键词： Dynamic Models Inverse Response Fixed-Bed Catalytic Reactors Simulation

Peristomal variceal bleeding treated by coil embolization using a percutaneous transhepatic approach

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World Journal of Clinical Cases 2016年第1期4卷 25-29页

作者： Macello José Sampaio maciel Osvaldo Ignácio Pereira Joaquim Maurício Motta Leal filho Enio Ziemiecki Junior Susyanne Lavor Cosme Moisés Amancio Souza Francisco Cesar Carnevale Radiology Department of Heart Institute Hospital das ClínicasFaculdade de Medicina da Universidade de São Paulo

Peristomal variceal bleeding due to portal hypertension is an entity that has rarely been reported with 3%-4% risk of death.A 68-year-old woman who had undergone a palliative colostomy(colorectal carcinoma) presented with a massive hemorrhage from the colostomy *** her oncological status with medial and right hepatic veins thrombosis due to liver metastasis invasion,an emergency transhepatic coil embolization was successfully *** treatment modality for these cases has not been *** transhepatic coil embolization of varices is a safe and effective choice in patients who present with life threatening bleeding and exhibit contraindications to transjugular intrahepatic portosystemic shunt.

关键词： Ectopic variceal bleeding Stomal bleeding Percutaneous transhepatic embolization Colostomy Cirrhosis Hemostasis

Distinct T helper cell-mediated antitumor immunity:T helper 2 cells in focus

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Cancer Pathogenesis and Therapy 2023年第1期1卷 76-86页

作者： Rafael Cardoso maciel Costa Silva Marcela Freitas Lopes Leonardo Holanda Travassos Laboratory of Immunoreceptors and Signaling Carlos Chagas Filho Biophysics InstituteFederal University of Rio de JaneiroRio de Janeiro 21941-902Brazil Laboratory of Immunity Biology George DosReis Carlos Chagas Filho Biophysics InstituteFederal University of Rio de JaneiroRio de Janeiro 21941-902Brazil

The adaptive arm of the immune system is crucial for appropriate antitumor immune *** is generally accepted that clusters of differentiation 4^(+)(CD4^(+))T cells,which mediate T helper(Th)1 immunity(type 1 immunity),are the primary Th cell subtype associated with tumor *** this review,we discuss evidence showing that antitumor immunity and better prognosis can be associated with distinct Th cell subtypes in experimental mouse models and humans,with a focus on Th2 *** aim of this review is to provide an overview and understanding of the mechanisms associated with different tumor outcomes in the face of immune responses by focusing on the(1)site of tumor development,(2)tumor properties(i.e.,tumor metabolism and cytokine receptor expression),and(3)type of immune response that the tumor initially ***,we discuss how low-tolerance organs,such as lungs and brains,might benefit from a less tissue-destructive immune response mediated by Th2 *** addition,Th2 cells antitumor effects can be independent of CD8^(+)T cells,which would circumvent some of the immune escape mechanisms that tumor cells possess,like low expression of major histocompatibility-I(MHC-I).Finally,this review aims to stimulate further studies on the role of Th2 cells in antitumor immunity and briefly discusses emerging treatment options.

关键词： Cancer Immunology Adaptive immunity Immunotherapy Immunogenetics Antitumor immune response