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Computer Modeling in Engineering & Sciences 2017年第3期113卷 367-387页

作者： C.F.Loeffle L.Zamprogno W.J.Mansur A.Bulcao DEM/PPGEM Federal University of Espírito Santo PGSU petrobras PEC/LAMEMO/COPPE/Federal University of Rio de Janeiro cenpes petrobras

This study evaluates the effectiveness of a new technique that transforms doma in integrals into boundary integrals that is applicable to the boundary element *** mulations were conducted in which two-dimensional surfaces were approximated by inter polation using radial basis functions with full and compact *** involving Poisson’s equation are presented using the boundary element method and the proposed te chnique with compact radial basis *** advantages and the disadvantages are e xamined through *** effects of internal poles,the boundary mesh refinemen t and the value for the support of the radial basis functions on performance are assessed.

关键词： Interpolations radial basis functions boundary element method Poisson’s equation

Characterization of the Lipid Components in <i>Desmodesmus</i>and <i>Scenedesmus</i>Strains: Lipid Content, Lipid Classes and Fatty Acid Profile

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American Journal of Plant Sciences 2020年第12期11卷 2103-2121页

作者： Carolina Vieira Viegas Gisel Chenard Díaz Yordanka Reyes Cruz Leonardo Brantes Bacellar Mendes GREETEC Laboratory Federal University of Rio de Janeiro (UFRJ) Rio de Janeiro Brazil cenpes/petrobras—Leopoldo Américo Miguez de Mello Research Center Rio de Janeiro Brazil

The lipid composition in terms of the amount of neutral lipids, free fatty acids and polar lipid content is of great importance to make full use possible of this fraction and to define the suitability of its application, either as a raw material for fuel production, nutraceutical purposes or feed. In addition to the fatty components present in the lipid extract, other components may be included, such as: carotenoids, pigments and sterols. The microalgae studied in this work, Scenedesmus sp. and Desmodesmus sp., were subjected to the same growth conditions and evaluated for lipid content, quantification and diversity of lipid components as well as its fatty acid profile. For lipid determination two extraction methods were compared: the J: Schmid-Bondzynski-Ratzlaff and Bligh & Dyer method. For Desmodesmus sp. 5.43% ± 0.41% and 9.18% ± 0.33% of lipids were obtained on an ash-free dry weight basis and for Scenedesmus sp. 12.46% ± 0.38% and 8.16% ± 0.42% of lipids were obtained on an ash-free dry weight basis using for both methods J:

关键词： Microalgae Desmodesmus sp. Scenedesmus sp.

An Adaptive Load Stepping Algorithm for Path-Dependent Problems Based on Estimated Convergence Rates

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Computer Modeling in Engineering & Sciences 2017年第3期113卷 325-342页

作者： M.T.C.Araújo Fernandes C.O.Cardoso W.J.Mansur Civil Engineering Department/COPPE/Federal University of Rio de Janeiro Ilha do FundaoP.B.6850621945-970 Rio de JaneiroRJBrazil petrobras/cenpes Av.Horácio Macedo950Ilha do Fundao21941-915 Rio de JaneiroRJBrazil Civil Engineering Department/COPPE/Federal University of Rio de Janeiro Ilha do FundaoP.B.6850621945-970 Rio de JaneiroRJBrazil

A new adaptive(automatic)time stepping algorithm,called RCA(Rate of Convergence Algorithm)is *** new algorithm was applied in nonlinear finite element analysis of path-dependent *** step size is adjusted by monitoring the estimated convergence rate of the nonlinear iterative *** RCA algorithm is relatively simple to implement,robust and its performance is comparable to,and in some cases better than,the automatic load incrementaion algorithm existent in commercial *** about the convergence rate of nonlinear iterative processes,an estimation of the rate and a study of the parameters of the RCA algorithm are *** show the capacity of the algorithm to adjust the increment size,detailed discussions based on results for different limit load analyses are *** results obtained by RCA algorithm are compared with those by ABAQUS?,one of the most powerful nonlinear FEA(Finite Element Analysis)commercial software,in order to verify the capability of RCA algorithm to adjust the increment size along nonlinear analyses.

关键词： Rate of convergence nonlinear automatic load incrementation limit load

Use of Perovskite-Type Lanthanum Nickelate Synthesized by the Polymeric Precursor Method in the Steam Reforming Reaction of Methane

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Materials Sciences and Applications 2012年第6期3卷 363-368页

作者： Daniele M.H.Martinelli Dulce M.A.Melo Anne M.Garrido Pedrosa Antonio E.Martinelli Marcus A.de F.Melo Mary K.S.Batista Roberto C.Bitencourt Department of Chemistry Federal University of Rio Grande do NorteCCETNatalBrazil Department of Chemistry Federal University of SergipeCCETSao CristóvaoBrazil Research Center petrobras—cenpes Rio de JaneiroBrazil

In the current work, LaNiO3 perovskite was synthesized using the polymeric precursor method. The materials were thermally treated at 300°C for 2 hours, subsequently supported on alumina or zirconia and finally calcined at 800°C for 4 hours. The resulting samples were characterized by X-ray diffraction, thermogravimetry, BET surface area and thermo-programmed reduction. Steam reforming reactions were carried out at 750°C and 6 bar during 4 hours using a pilot reactor under a H2O:CH4 ratio of 2.5. The mass of catalysts was about 5.7 g. X-ray diffraction patterns confirmed the formation of the perovskite structure in all samples prepared. The results also showed that lanthanum nickelate was more efficient when supported on alumina than zirconia. Finally, it was observed that the methane conversion was approximately 94% and the selectivity to hydrogen was about 70%. In all cases low selectivity to CO and CO2 was verified.

关键词： Lanthanum Nickelate Perovskite Polymeric Precursor Method Steam Reforming Reaction

Biodiesel production by hydroesterification of microalgal biomass using heterogeneous catalyst

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Natural Science 2012年第10期4卷 778-783页

作者： Yordanaka Reyes Gisel Chenard Donato Aranda Cristiane Mesquita Mariana Fortes Rafael Joao Leonardo Bacellar Department of Chemical Engineering Federal University of Rio de Janeiro(UFRJ)Rio de JaneiroBrazil Research and Development Center“Leopoldo Américo Miguez de Mello”(cenpes) PetrobrasRio de JaneiroBrasil

This paper assesses the hydroesterification process for the production of Biodiesel from Monoraphidium contortum (MORF-1) microalgae biomass, as it is a sustainable alternative not only economically, but also environmentally and ecologically to replace petroleum diesel fuel. The Biodiesel studied in this work was obtained from fatty acid esterification, a product of microalgae and methanol biomass hydrolysis reaction. CBMM’s (HY-340) niobium oxide powder was used as catalyst. The reactions were carried out in a properly closed autoclave reactor (batch), where the reagents were mixed under constant stirring at 500 rpm for hydrolysis and esterification. The products generated were submitted to gas chromatography and oxidative stability analysis. The hydroesterification process showed itself to be a promising alternative to the conventional biodiesel production process (transesterification) as it favors the use of feedstocks with any acidity and moisture content and may be performed with acid catalyst, which favors high conversions in a small range of time (30 minutes).

关键词： Biodiesel Microalgae Hydroesterification Biomass Heterogeneous

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

External versus Internal Loads of Nutrients of an Urban Eutrophic Tropical Reservoir （Southeastern Brazil）

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Journal of Environmental Science and Engineering(A) 2012年第5期1卷 598-610页

作者： Antonio A. Mozeto MarceloMontini Simone A. Braz Felipe G. Martins Aloisio Soares Marcos Roberto L.do Nascimento Francisco Antonio R. Barbosd Pedro S. Fadini Bias M. de Faria Environmental Biogeochemistry Laboratory (LBGqA) Chemistry Department Federal University of S6o Carlos (UFSCar) S~oCarlos SP13565-905 Brazil Biological Sciences Institute (1CB) Federal University of Minas Gerais (UFMG) Belo Horizonte MG30161-970 Brazil Povos de Caldas Laboratory (LAPOC) Brazilian National Commission for Nuclear Energy (CNEN) Pogos de CaldasMG37701-970 Brazil Research and Development Center (cenpes)-petrobras Cidade Universit6ria Rio de Janeiro RJ21941-915 Brazil

ZSM5 as a Potential Catalyst for Glycerol Pyrolysis

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Journal of Sustainable Bioenergy Systems 2014年第1期4卷 61-67页

作者： Margarida L.Castello Jo Dweck Donato A.G.Aranda Rosana C.L.Pereira Manoel J.R.Guimaraes Neto Chemical School Federal University of Rio de JaneiroRio de JaneiroBrazil Fluminense Federal Institute—Campus Macae MacaeBrazil petrobras’Research Center Rio de JaneiroBrazil

Glycerol is a substance known to humankind for many years now, and among other products, in which composition it is used, are the pharmaceutical, cosmetic, food, paints and varnishes REF _Ref382993082 \r \h [1]REF _Ref382993086 \r \h [6]. The abundance of its supply leads to search for new uses, whether as a plasticizer for biodegradable polymers REF _Ref382993096 \r \h [7], its transformation into other substances like propylene and derivatives or other hydrocarbons [8] [9], the production of hydrogen for energy purposes REF _Ref382993109 \r \h [10], or even direct burning, making glycerol a fuel for boilers, for example. The aim of this work was to investigate the action of the zeolite ZSM5 on glycerol fast pyrolysis at 600°C. The tests were done with a mixture of glycerol-ZSM5 recently prepared using approximately equal volumes of glycerol and the catalyst, and the effluent gases from the fast pyrolysis have been analyzed in a chromatography/mass spectrometry (GC/MS) system. Experiments showed that ZSM5 acts in the pyrolysis of glycerol leading to a large number of substances, from oxygenated products to hydrocarbons, which are part of typical compositions of naphtha, diesel and gasoline petroleum derived products.

关键词： Glycerol ZSM5 Pyrolysis