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Antonio J. A. Meirelles - One of the best experts on this subject based on the ideXlab platform.
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binary solid liquid equilibrium systems containing Fatty acids Fatty Alcohols and triolein by differential scanning calorimetry
Fluid Phase Equilibria, 2015Co-Authors: Flávio Cardoso De Matos, Mariana C. Costa, Antonio J. A. Meirelles, Eduardo A. C. BatistaAbstract:Abstract The solid–liquid phase diagrams of six binary mixtures composed of triolein plus Fatty acids (triolein (1) + capric acid (2), triolein (1) + lauric acid (3) and triolein (1) + myristic acid (4)) and triolein plus Fatty Alcohols (triolein (1) + 1-decanol (5), triolein (1) + 1-dodecanol (6) and triolein (1) + 1-tetradecanol (7)) were studied by differential scanning calorimetry (DSC). Experimental results clearly show that systems formed by triolein + capric acid, triolein + 1-decanol and triolein + 1-dodecanol show eutectic behavior, while for the other binary systems, the occurrence of an eutectic point very close to the melting temperature of pure triolein was observed. Experimental data were used to adjust the parameters of the three-suffix Margules and NRTL models.
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High Pressure Solid-Liquid Equilibrium of Fatty Alcohols Binary Systems from 1-Dodecanol, 1-Tetradecanol, 1-Hexadecanol, and 1-Octadecanol
Journal of Chemical & Engineering Data, 2015Co-Authors: Natália D.d. Carareto, Mariana C. Costa, Antonio J. A. Meirelles, Jérôme PaulyAbstract:The melting temperatures of four Fatty Alcohols, 1-dodecanol, 1-tetradecanol, 1-hexadecanol, and 1-octadecanol, were measured at atmospheric pressure using a μDSC calorimeter and at higher pressures (up to 80 MPa) thanks to a dedicated microscope. The solid–liquid phase diagrams of six binary mixtures formed by these Fatty Alcohols, namely, 1-dodecanol + 1-tetradecanol, 1-dodecanol + 1-hexadecanol, 1-dodecanol + 1-octadecanol, 1-tetradecanol + 1-hexadecanol, 1-tetradecanol + 1-octadecanol, and 1-hexadecanol + 1-octadecanol systems, were also measured using high pressure microscopy within the range of 0.1 MPa to 80 MPa. In addition, the phase diagrams of the 1-dodecanol + 1-tetradecanol, 1-tetradecanol + 1-hexadecanol, and 1-hexadecanol + 1-octadecanol systems were also measured by DSC in order to compare the results obtained from the microscopy. On the basis of the experimental data, it could be concluded that the behavior of the phase diagrams is slightly affected by the pressure, even within very large ...
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on the solid liquid phase diagrams of binary mixtures of even saturated Fatty Alcohols systems exhibiting peritectic reaction
Thermochimica Acta, 2014Co-Authors: Natalia D D Carareto, Mariana C. Costa, Marlus P Rolemberg, Adenilson Dos O Santos, L P Cardoso, Antonio J. A. MeirellesAbstract:Abstract The solid–liquid phase diagrams of the following binary mixtures of even saturated Fatty Alcohols are reported in the literature for the first time: 1-octanol (C8OH) + 1-decanol (C10OH), 1-decanol + 1-dodecanol (C12OH), 1-dodecanol + 1-hexadecanol (C16OH) and 1-tetradecanol (C14OH) + 1-octadecanol (C18OH). The phase diagrams were obtained by differential scanning calorimetry (DSC) using a linear heating rate of 1 K min−1 and further investigated by using a stepscan DSC method. X-ray diffraction (XRD) and polarized light microscopy were also used to complement the characterization of the phase diagrams which have shown a complex global behavior, presenting not only peritectic and eutectic reactions, but also the metatectic reaction and partial immiscibility on solid state.
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Solid-liquid equilibrium of triolein with Fatty Alcohols
Brazilian Journal of Chemical Engineering, 2013Co-Authors: Guilherme J. Maximo, Mariana C. Costa, Antonio J. A. MeirellesAbstract:Triacylglycerols and Fatty Alcohols are used in the formulation of cosmetic, pharmaceutical and food products. Although information about the phase transitions of these compounds and their mixtures is frequently required for design and optimization of processes and product formulation involving these substances, these data are still scarce in the literature. In the present study, the solid-liquid phase diagrams of two binary systems composed of triolein + 1-hexadecanol and triolein + 1-octadecanol were evaluated by differential scanning calorimetry (DSC) and optical microscopy. The experimental data were compared with predicted data by solving the phase equilibrium equations using an algorithm implemented in MATLAB. The liquid-phase activity coefficients were calculated using the Margules equation (two- and three-suffix) and the UNIFAC model (original and modified Dortmund model). The approaches used for calculating system equilibrium allowed an accurate prediction of the liquidus line with low deviations from the experimental data.
Mariana C. Costa - One of the best experts on this subject based on the ideXlab platform.
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binary solid liquid equilibrium systems containing Fatty acids Fatty Alcohols and triolein by differential scanning calorimetry
Fluid Phase Equilibria, 2015Co-Authors: Flávio Cardoso De Matos, Mariana C. Costa, Antonio J. A. Meirelles, Eduardo A. C. BatistaAbstract:Abstract The solid–liquid phase diagrams of six binary mixtures composed of triolein plus Fatty acids (triolein (1) + capric acid (2), triolein (1) + lauric acid (3) and triolein (1) + myristic acid (4)) and triolein plus Fatty Alcohols (triolein (1) + 1-decanol (5), triolein (1) + 1-dodecanol (6) and triolein (1) + 1-tetradecanol (7)) were studied by differential scanning calorimetry (DSC). Experimental results clearly show that systems formed by triolein + capric acid, triolein + 1-decanol and triolein + 1-dodecanol show eutectic behavior, while for the other binary systems, the occurrence of an eutectic point very close to the melting temperature of pure triolein was observed. Experimental data were used to adjust the parameters of the three-suffix Margules and NRTL models.
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High Pressure Solid-Liquid Equilibrium of Fatty Alcohols Binary Systems from 1-Dodecanol, 1-Tetradecanol, 1-Hexadecanol, and 1-Octadecanol
Journal of Chemical & Engineering Data, 2015Co-Authors: Natália D.d. Carareto, Mariana C. Costa, Antonio J. A. Meirelles, Jérôme PaulyAbstract:The melting temperatures of four Fatty Alcohols, 1-dodecanol, 1-tetradecanol, 1-hexadecanol, and 1-octadecanol, were measured at atmospheric pressure using a μDSC calorimeter and at higher pressures (up to 80 MPa) thanks to a dedicated microscope. The solid–liquid phase diagrams of six binary mixtures formed by these Fatty Alcohols, namely, 1-dodecanol + 1-tetradecanol, 1-dodecanol + 1-hexadecanol, 1-dodecanol + 1-octadecanol, 1-tetradecanol + 1-hexadecanol, 1-tetradecanol + 1-octadecanol, and 1-hexadecanol + 1-octadecanol systems, were also measured using high pressure microscopy within the range of 0.1 MPa to 80 MPa. In addition, the phase diagrams of the 1-dodecanol + 1-tetradecanol, 1-tetradecanol + 1-hexadecanol, and 1-hexadecanol + 1-octadecanol systems were also measured by DSC in order to compare the results obtained from the microscopy. On the basis of the experimental data, it could be concluded that the behavior of the phase diagrams is slightly affected by the pressure, even within very large ...
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on the solid liquid phase diagrams of binary mixtures of even saturated Fatty Alcohols systems exhibiting peritectic reaction
Thermochimica Acta, 2014Co-Authors: Natalia D D Carareto, Mariana C. Costa, Marlus P Rolemberg, Adenilson Dos O Santos, L P Cardoso, Antonio J. A. MeirellesAbstract:Abstract The solid–liquid phase diagrams of the following binary mixtures of even saturated Fatty Alcohols are reported in the literature for the first time: 1-octanol (C8OH) + 1-decanol (C10OH), 1-decanol + 1-dodecanol (C12OH), 1-dodecanol + 1-hexadecanol (C16OH) and 1-tetradecanol (C14OH) + 1-octadecanol (C18OH). The phase diagrams were obtained by differential scanning calorimetry (DSC) using a linear heating rate of 1 K min−1 and further investigated by using a stepscan DSC method. X-ray diffraction (XRD) and polarized light microscopy were also used to complement the characterization of the phase diagrams which have shown a complex global behavior, presenting not only peritectic and eutectic reactions, but also the metatectic reaction and partial immiscibility on solid state.
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Solid-liquid equilibrium of triolein with Fatty Alcohols
Brazilian Journal of Chemical Engineering, 2013Co-Authors: Guilherme J. Maximo, Mariana C. Costa, Antonio J. A. MeirellesAbstract:Triacylglycerols and Fatty Alcohols are used in the formulation of cosmetic, pharmaceutical and food products. Although information about the phase transitions of these compounds and their mixtures is frequently required for design and optimization of processes and product formulation involving these substances, these data are still scarce in the literature. In the present study, the solid-liquid phase diagrams of two binary systems composed of triolein + 1-hexadecanol and triolein + 1-octadecanol were evaluated by differential scanning calorimetry (DSC) and optical microscopy. The experimental data were compared with predicted data by solving the phase equilibrium equations using an algorithm implemented in MATLAB. The liquid-phase activity coefficients were calculated using the Margules equation (two- and three-suffix) and the UNIFAC model (original and modified Dortmund model). The approaches used for calculating system equilibrium allowed an accurate prediction of the liquidus line with low deviations from the experimental data.
Jérôme Pauly - One of the best experts on this subject based on the ideXlab platform.
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High Pressure Solid-Liquid Equilibrium of Fatty Alcohols Binary Systems from 1-Dodecanol, 1-Tetradecanol, 1-Hexadecanol, and 1-Octadecanol
Journal of Chemical & Engineering Data, 2015Co-Authors: Natália D.d. Carareto, Mariana C. Costa, Antonio J. A. Meirelles, Jérôme PaulyAbstract:The melting temperatures of four Fatty Alcohols, 1-dodecanol, 1-tetradecanol, 1-hexadecanol, and 1-octadecanol, were measured at atmospheric pressure using a μDSC calorimeter and at higher pressures (up to 80 MPa) thanks to a dedicated microscope. The solid–liquid phase diagrams of six binary mixtures formed by these Fatty Alcohols, namely, 1-dodecanol + 1-tetradecanol, 1-dodecanol + 1-hexadecanol, 1-dodecanol + 1-octadecanol, 1-tetradecanol + 1-hexadecanol, 1-tetradecanol + 1-octadecanol, and 1-hexadecanol + 1-octadecanol systems, were also measured using high pressure microscopy within the range of 0.1 MPa to 80 MPa. In addition, the phase diagrams of the 1-dodecanol + 1-tetradecanol, 1-tetradecanol + 1-hexadecanol, and 1-hexadecanol + 1-octadecanol systems were also measured by DSC in order to compare the results obtained from the microscopy. On the basis of the experimental data, it could be concluded that the behavior of the phase diagrams is slightly affected by the pressure, even within very large ...
Natália D.d. Carareto - One of the best experts on this subject based on the ideXlab platform.
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Solid-liquid equilibrium for Fatty Alcohols binary system by differential scanning calorimetry
2017Co-Authors: Natália D.d. CararetoAbstract:Resumo: Álcoois graxos são constituintes minoritários de tecidos vegetais, sendo encontrados principalmente em ceras. São utilizados na indústria como emulsificantes, surfactantes ou emolientes. Atualmente, existem muitos estudos sobre o uso de álcoois graxos associados a ácidos graxos como substitutos do processo de hidrogenação para a fabricação de margarinas e outras emulsões. O conhecimento do equilíbrio sólido-líquido de misturas binárias de álcoois graxos é uma ferramenta importante para se entender o comportamento de misturas mais complexas. Assim, neste trabalho se objetivou construir diagramas de equilíbrio sólido-líquido de misturas binárias de álcoois graxos saturados pares contendo de oito a dezoito átomos na cadeia carbônica, a partir da calorimetria Exploratória Diferencial, com método experimental previamente utilizado por Rolemberg (2002) e Costa (2004) para ácidos graxos e triacilgliceróis. Para complementar os resultados também foram capturadas imagens de microscopia óptica com controle de temperatura. Os sistemas aqui estudados apresentaram três comportamentos diferentes da linha liquidus: no primeiro grupo estão os sistemas que apresentaram apenas o ponto eutético, no segundo aqueles com ponto eutético e ponto peritético e o último grupo exibe nenhum desses pontos. Para os sistemas que apresentaram ponto peritético, pode-se observar nas imagens de microscopia a recristalização de algumas amostras com o aumento de temperatura, o que evidencia a ocorrência da reação metatética para tais sistemas. Foram utilizados os modelos termodinâmicos para coeficiente de atividade Margules 2 e 3-sufixos e NRTL para ajuste dos dados experimentais dos sistemas que apresentaram apenas ponto eutético simples e ponto eutético e peritético e obteve-se um valor de DQM satisfatório para todos os casos. Já para o modelo preditivo UNIFAC original, os desvios com relação aos valores experimentais foram altos, o que se supõe ser proveniente de simplificações, como a hipótese de uma fase sólida pura, o que neste trabalho se mostrou inadequadoAbstract:Fatty Alcohols are minor constituents of vegetal tissues, being mainly found in vegetal waxes. Fatty Alcohols are used in industry as emulsifiers, surfactants or emollients agents. There are many studies about the use of Fatty alcohol associated with Fatty acids as substitutes for the hydrogenation process of margarine manufacturing and other edible emulsions, for example. Solid-liquid equilibrium of binary mixtures of Fatty Alcohols is na important tool for understanding the behavior of Fatty complex mixtures. Thus, this work aimed to study diagrams of solid-liquid equilibrium of binary systems of even saturated Fatty Alcohols from eight to eighteen atoms in the carbon chain by differential scanning calorimetry (DSC). This method was previously used by Rolemberg (2002) and Costa et al. (2007a, 2009a, 2009b, 2009c) for Fatty acids and triacylglycerols systems. To complement the study were also captured images for some systems by optical microscope with temperature control. The liquidus line of the studied systems showed three different behaviors: one showed only the eutectic point, another the eutectic and peritectic points or neither eutectic nor peritectic point. For systems that had peritectic point, it could be observed in the microscopy images the recrystallization of the compositions that was investigated on the microscopy, even with the temperature increase. This behavior corroborates the existence of the metatetic reaction in these systems. Margules-2-suffix, Margules-3-suffix, NRTL, UNIFAC and UNIFAC-Dortmund models were applied to fit the experimental data. The best fit for the systems that exhibit peritectic and eutectic points were obtained through Margules and NRTL models. UNIFAC and UNIFAC-Dortmund models have showed high deviation compared to experimental data of the modeled system
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High Pressure Solid-Liquid Equilibrium of Fatty Alcohols Binary Systems from 1-Dodecanol, 1-Tetradecanol, 1-Hexadecanol, and 1-Octadecanol
Journal of Chemical & Engineering Data, 2015Co-Authors: Natália D.d. Carareto, Mariana C. Costa, Antonio J. A. Meirelles, Jérôme PaulyAbstract:The melting temperatures of four Fatty Alcohols, 1-dodecanol, 1-tetradecanol, 1-hexadecanol, and 1-octadecanol, were measured at atmospheric pressure using a μDSC calorimeter and at higher pressures (up to 80 MPa) thanks to a dedicated microscope. The solid–liquid phase diagrams of six binary mixtures formed by these Fatty Alcohols, namely, 1-dodecanol + 1-tetradecanol, 1-dodecanol + 1-hexadecanol, 1-dodecanol + 1-octadecanol, 1-tetradecanol + 1-hexadecanol, 1-tetradecanol + 1-octadecanol, and 1-hexadecanol + 1-octadecanol systems, were also measured using high pressure microscopy within the range of 0.1 MPa to 80 MPa. In addition, the phase diagrams of the 1-dodecanol + 1-tetradecanol, 1-tetradecanol + 1-hexadecanol, and 1-hexadecanol + 1-octadecanol systems were also measured by DSC in order to compare the results obtained from the microscopy. On the basis of the experimental data, it could be concluded that the behavior of the phase diagrams is slightly affected by the pressure, even within very large ...
Yinlong Guo - One of the best experts on this subject based on the ideXlab platform.
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simultaneous analysis of Fatty Alcohols Fatty aldehydes and sterols in thyroid tissues by electrospray ionization ion mobility mass spectrometry based on charge derivatization
Analytical Chemistry, 2020Co-Authors: Yunjun Wang, Yanjing Cao, Qing Guan, Tuanqi Sun, Yuqi Cao, Li Zhang, Yinlong GuoAbstract:In this work, we developed a rapid and high-sensitivity method for simultaneous analyses of Fatty Alcohols, Fatty aldehydes, and sterols by combining the optimized derivatization reaction with electrospray ionization-ion mobility-mass spectrometry (ESI-IM-MS). Pyridine and thionyl chloride were used as derivatization reagents as they were easily removed after the derivatization reaction and could generate permanently charged tags on different functional groups including hydroxyls and aldehydes. Through this one-step derivatization reaction, the sensitivity of detection for Fatty Alcohols, Fatty aldehydes, and sterols was significantly increased. Moreover, the introduction of ion mobility spectrometry (IMS), offering an additional resolution power, ensured more sensitive and accurate detection of derivative products without increasing analytical time. Being connected with high-performance liquid chromatography, more than 15 kinds of compounds were analyzed within 4 min. Relative quantification using peak intensity ratios between d0-/d5-labeled ions were subsequently applied for analyzing these 15 kinds of compounds in human thyroid carcinoma and para-carcinoma tissues. The results showed significant differences in content of some analytes between these two kinds of tissues (p < 0.05). The correlations between most of the analytes in thyroid carcinoma tissues are better than the correlations in para-carcinoma tissues.
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n alkylpyridinium quaternization combined with liquid chromatography electrospray ionization tandem mass spectrometry a highly sensitive method to quantify Fatty Alcohols in thyroid tissues
Analytica Chimica Acta, 2014Co-Authors: Yanjing Cao, Qing Guan, Tuanqi Sun, Hang Wang, Jiapeng Leng, Yinlong GuoAbstract:A highly sensitive method was developed for the identification and quantification of Fatty Alcohols in biological tissues. In the presence of pyridine-d(0) and triflic anhydride (Tf2O), Fatty Alcohols were converted into permanently charged N-alkylpyridinium ions. Stable isotope-labeled derivatives were generated by pyridine-d(5) and added as internal standard (IS). The mixture was analyzed by liquid chromatography coupled to positive electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). This method was optimized and validated in terms of reaction time, derivatization efficiency, stability, desalting, and ion suppression effect. Besides, Fatty Alcohols exhibited good linear relationship (r2 > 0.993) over the concentration range of 10 ng mL(1)-1 mu g mL(1). The limits of detection (LODs) were lowered from previously reported 0.1 ng mL(1) to 0.25 pg mL(1). Precision (RSD% < 15.6%), accuracy (93.0-107.2%), matrix effect, and recovery (in thyroid tissues) were validated as well. Finally, this method was applied for the analysis of ten even carbon-numbered Fatty Alcohols (C8-C24) in human thyroid procedure achieved a sufficient enhancement of sensitivity. Furthermore, the exact concentrations of total (free and esterfied) Fatty Alcohols in human thyroid tissues were measured.
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comparison of hair Fatty Alcohols by n alkylpyridinium isotope quaternization and matrix assisted laser desorption ionization mass spectrometry for drug abuse monitoring
Chinese Journal of Chemistry, 2012Co-Authors: Hang Wang, Li Zhang, Haoyang Wang, Jing Zhang, Xianyi Zhuo, Yi Huang, Yinlong GuoAbstract:Based on our previous report on N-alkylpyridinium isotope quaternization (NAPIQ) for the analysis of alcoholic and α,β-unsaturated ketone compounds, we have further applied NAPIQ method in the screening of hair lipids in drug abusers. Relative isotopic quantification was used for comparison of Fatty Alcohols between normal and drug abuse group. The NAPIQ strategy was proven to be a high-throughput method in the metabolic comparison studies of different group samples. The attached N-cationic pyridinium significantly improved the detection sensitivity for these Fatty Alcohols in matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometric (MALDI-FTMS) analysis. The experimental results showed that the levels of Fatty Alcohols in the hair of heroin abuse group decreased significantly compared with the normal groups, which may be the results of the inducing of peroxidation enzyme. NAPIQ was proven to be an effective and alternative method in the research of Fatty alcoholic metabolism for drug abuse monitoring.
