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Guiyin Fang - One of the best experts on this subject based on the ideXlab platform.
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microencapsulation and thermal properties of Myristic Acid with ethyl cellulose shell for thermal energy storage
Applied Energy, 2018Co-Authors: Guruprasad Alva, Guiyin FangAbstract:Abstract Encapsulating phase change material (PCM) is an effective way to avoid leakage and prevent contact with external environment. In this work, Myristic Acid (MA) was used as PCM to store and release latent heat through solid–liquid phase change and ethyl cellulose (EC) was employed as shell to microencapsulate MA for preventing the leakage of melted MA. The novel microencapsulated phase change materials (MPCMs) with MA core and EC shell were fabricated by emulsification–solvent evaporation method. The morphology and particle size of the MPCMs were measured by scanning electronic microscope (SEM), and similar and complete spheres were observed. Chemical structure and crystal phase of MPCMs were analyzed by Fourier transformation infrared spectroscope (FT–IR) and X–ray diffractometer (XRD), finding that EC and MA are well combined by physical action without chemical reaction. Thermogravimetric analyzer (TGA) was used to investigate the thermal stability, and the results revealed that MPPCMs possess excellent thermal stability at working temperature. The thermal cycling tests indicated that the MPCM have excellent thermal reliability. Differential scanning calorimeter (DSC) was employed to analyze the thermal properties of MPCMs. The most satisfying sample is MCPM1 with phase change enthalpy of 122.61 J/g and phase change temperature of 53.32 °C. Hence, the application of the prepared MPCMs in low–temperature solar energy systems has great potential in the future.
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synthesis and characterization of microencapsulated Myristic Acid palmitic Acid eutectic mixture as phase change material for thermal energy storage
Applied Energy, 2017Co-Authors: Guruprasad Alva, Xiang Huang, Lingkun Liu, Guiyin FangAbstract:In this work microencapsulation of Myristic Acid–palmitic Acid (MA–PA) eutectic mixture with silica shell using sol−gel method has been attempted. The core phase change material (PCM) for thermal energy storage was Myristic Acid−palmitic Acid eutectic mixture and the shell material to prevent the PCM core from leakage was silica prepared from methyl triethoxysilane (MTES). Thermal properties of the microcapsules were measured by differential scanning calorimeter (DSC). The morphology and particle size of the microcapsules were examined by scanning electronic microscope (SEM). Fourier transformation infrared spectrophotometer (FT–IR) and X–ray diffractometer (XRD) were used to investigate the chemical structure and crystalloid phase of the microcapsules respectively. The DSC results indicated that microencapsulated phase change material (MPCM) melts at 46.08°C with a latent heat of 169.69kJkg−1 and solidifies at 44.35°C with a latent heat of 159.59kJkg−1. The thermal stability of the microcapsules was analyzed by a thermogravimeter (TGA). The results indicated that the MPCM has good thermal stability and is suitable for thermal energy storage application.
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dynamic performances of solar heat storage system with packed bed using Myristic Acid as phase change material
Energy and Buildings, 2011Co-Authors: Guiyin FangAbstract:Abstract This paper is aimed at analyzing the thermal characteristics of packed bed containing spherical capsules, used in a latent heat thermal storage system with a solar heating collector. Myristic Acid is selected as phase change material (PCM), and water is used as heat transfer fluid (HTF). The mathematical model based on the energy balance of HTF and PCM is developed to calculate the temperatures of PCM and HTF, solid fraction and heat release rate during the solidifying process. The latent efficiency, which is defined as the ratio between the instantaneous released latent heat and the maximum released heat, is introduced to indicate the thermal performances of the system. The inlet temperature of HTF (50 °C), flow rate of HTF (10 kg/min) and initial temperature of HTF (66 °C) were chosen for studying thermal performances in solar heat storage system. The influences of inlet temperature of HTF, flow rate of HTF and initial temperatures of HTF and PCM on the latent efficiency and heat release rate are also analyzed and discussed.
Jose C Fernandezcheca - One of the best experts on this subject based on the ideXlab platform.
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Myristic Acid potentiates palmitic Acid induced lipotoxicity and steatohepatitis associated with lipodystrophy by sustaning de novo ceramide synthesis
Oncotarget, 2015Co-Authors: Laura Martinez, Sandra Torres, Anna Baulies, Cristina Alarconvila, Montserrat Elena, Gemma Fabrias, Josefina Casas, Joan Caballeria, Jose C FernandezchecaAbstract:Palmitic Acid (PA) induces hepatocyte apoptosis and fuels de novo ceramide synthesis in the endoplasmic reticulum (ER). Myristic Acid (MA), a free fatty Acid highly abundant in copra/palmist oils, is a predictor of nonalcoholic steatohepatitis (NASH) and stimulates ceramide synthesis. Here we investigated the synergism between MA and PA in ceramide synthesis, ER stress, lipotoxicity and NASH. Unlike PA, MA is not lipotoxic but potentiated PA-mediated lipoapoptosis, ER stress, caspase-3 activation and cytochrome c release in primary mouse hepatocytes (PMH). Moreover, MA kinetically sustained PA-induced total ceramide content by stimulating dehydroceramide desaturase and switched the ceramide profile from decreased to increased ceramide 14:0/ceramide16:0, without changing medium and long-chain ceramide species. PMH were more sensitive to equimolar ceramide14:0/ceramide16:0 exposure, which mimics the outcome of PA plus MA treatment on ceramide homeostasis, than to either ceramide alone. Treatment with myriocin to inhibit ceramide synthesis and tauroursodeoxycholic Acid to prevent ER stress ameliorated PA plus MA induced apoptosis, similar to the protection afforded by the antioxidant BHA, the pan-caspase inhibitor z-VAD-Fmk and JNK inhibition. Moreover, ruthenium red protected PMH against PA and MA-induced cell death. Recapitulating in vitro findings, mice fed a diet enriched in PA plus MA exhibited lipodystrophy, hepatosplenomegaly, increased liver ceramide content and cholesterol levels, ER stress, liver damage, inflammation and fibrosis compared to mice fed diets enriched in PA or MA alone. The deleterious effects of PA plus MA-enriched diet were largely prevented by in vivo myriocin treatment. These findings indicate a causal link between ceramide synthesis and ER stress in lipotoxicity, and imply that the consumption of diets enriched in MA and PA can cause NASH associated with lipodystrophy.
Hadi Fauzi - One of the best experts on this subject based on the ideXlab platform.
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sodium laurate enhancements the thermal properties and thermal conductivity of eutectic fatty Acid as phase change material pcm
Solar Energy, 2014Co-Authors: Hadi Fauzi, Hendrik Simon Cornelis Metselaar, T M I Mahlia, Mahyar SilakhoriAbstract:Abstract One way to improve the thermal properties of Myristic Acid/palmitic Acid (MA/PA) eutectic phase change material (PCM) is by adding an Acid-based surfactant. The incorporation of surfactant into MA/PA eutectic mixture can significantly increase the latent heat storage capacity and decrease the subcooling of material. In this study, the preparation of Myristic Acid/palmitic Acid (MA/PA) eutectic mixture with addition of 0%, 5%, 10%, 15%, and 20% sodium laurate (SL) as surfactant is reported and the influence of SL on thermal properties and thermal conductivity of the eutectic mixture is investigated. It was found that the addition of 10% SL to MA/PA eutectic mixture significantly lowered the phase transition temperature and the subcooling by 4.73 °C and 0.43 °C, respectively. In addition, the surfactant also increased the latent heat and the thermal conductivity to 15.14 J g−1 and 0.010 W m−1 K−1, respectively.
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phase change material optimizing the thermal properties and thermal conductivity of Myristic Acid palmitic Acid eutectic mixture with Acid based surfactants
Applied Thermal Engineering, 2013Co-Authors: Hadi Fauzi, Hendrik Simon Cornelis Metselaar, T M I Mahlia, Mahyar Silakhori, Hadi NurAbstract:Abstract In this study the addition of surfactant to fatty Acids as phase change materials (PCMs) for solar thermal applications is proposed. The incorporation of surfactant additives into a eutectic mixture of fatty Acids can significantly increase the value of latent heat storage and can suppress undercooling. We report the preparation of Myristic Acid/palmitic Acid (MA/PA) eutectic mixture as Phase Change Material (PCM) with addition of 0, 5, 10, 15, and 20% sodium myristate (SM), sodium palmitate (SP), and sodium stearate (SS), the influence of surfactant additives on thermal properties and thermal conductivity of eutectic mixtures. It was found that the addition of 5% SM, 5% SP, and 5% SS to MA/PA eutectic mixture is very effective in depressing the liquid/solid phase change temperature, reducing the undercooling and increasing the amount of latent heat of fusion as well as thermal conductivity of eutectic PCM compared to eutectic PCM without surfactants. Furthermore MA/PA + 5%SS has the highest latent heat of fusion of 191.85 J g −1 , while MA/PA + 5%SM showed the least undercooling of 0.34 °C and the highest thermal conductivity of 0.242 W m − 1 K −1 .
Ahmet Sari - One of the best experts on this subject based on the ideXlab platform.
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capric Myristic Acid vermiculite composite as form stable phase change material for thermal energy storage
Solar Energy, 2009Co-Authors: Ali Karaipekli, Ahmet SariAbstract:Abstract Phase change materials (PCMs) can be incorporated with building materials to obtain novel form-stable composite PCM which has effective energy storage performance in latent heat thermal energy storage (LHTES) systems. In this study, capric Acid (CA)–Myristic Acid (MA) eutectic mixture/vermiculite (VMT) composite was prepared as a novel form-stable PCM using vacuum impregnation method. The composite PCM was characterized using scanning electron microscope (SEM) and Fourier transformation infrared (FT-IR) analysis technique. Thermal properties and thermal reliability of the composite PCM were determined by differential scanning calorimetry (DSC) analysis. The CA–MA eutectic mixture could be retained by 20 wt% into pores of the VMT without melted PCM seepage from the composite and therefore, this mixture was described as form-stable composite PCM. Thermal cycling test showed that the form-stable composite PCM has good thermal reliability and chemical stability although it was subjected to 3000 melting/freezing cycling. Thermal conductivity of the form-stable CA–MA/VMT composite PCM was increased by about 85% by introducing 2 wt% expanded graphite (EG) into the composite. The increase in thermal conductivity was confirmed by comparison of the melting and freezing times of the CA–MA/VMT composite with that of CA–MA/VMT/EG composite. The form-stable PCM including EG can be used as energy absorbing building material such as lightweight aggregate for plaster, concrete compounds, fire stop mortar, and component of interior fill for wallboards or hollow bricks because of its good thermal properties, thermal and chemical reliability and thermal conductivity.
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capric Myristic Acid expanded perlite composite as form stable phase change material for latent heat thermal energy storage
Renewable Energy, 2008Co-Authors: Ali Karaipekli, Ahmet SariAbstract:Abstract The aim of this study is to prepare a novel form-stable phase change material (PCM) for latent heat thermal energy storage (LHTES) in buildings. A eutectic mixture of capric Acid (CA) and Myristic Acid (MA) is incorporated with expanded perlite (EP). Thermal properties, thermal reliability, and thermal conductivity of the form-stable composite PCM are determined. The maximum CA–MA absorption of EP was found to be 55 wt% without melted PCM seepage from the composite, and therefore this mixture was described as a form-stable composite. The form-stable composite PCM was characterized using the FT-IR spectroscopy method. The melting and freezing temperatures and latent heats of form-stable composite PCM were measured using DSC analysis. Thermal cycling test of the form-stable composite PCM indicated good thermal reliability in terms of changes in thermal properties after 5000 thermal cycling. The thermal conductivity of the form-stable CA–MA/EP composite PCM was increased about 58% by adding 10 wt% expanded graphite (EG). The form-stable CA–MA/EP/EG composite PCM was considered as an effective LHTES material in the building energy conservation due to suitable phase change temperatures, high latent capacities, good thermal reliability, and good thermal conductivity.
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Thermal performance of Myristic Acid as a phase change material for energy storage application
Renewable Energy, 2001Co-Authors: Ahmet Sari, Kamil KaygusuzAbstract:Thermal performance and phase change stability of Myristic Acid as a latent heat energy storage material has been studied experimentally. In the experimental study, the thermal performance and heat transfer characteristics of the Myristic Acid were tested and compared with other studies given in the literature. In the present study is included some parameters such as transition times, temperature range, and propagation of the solid–liquid interface as well as heat flow rate effect on the phase change stability of Myristic Acid as a phase change material (PCM). The experimental results showed that the melting stability of the PCM is better in the radial direction than the axial direction. The variety of the melting and solidification parameters of the PCM with the change of inlet water temperature is also studied. The results show that the better stability of the Myristic Acid was accomplished at low inlet water temperature compared with the obtained results at high inlet water temperature. We also observed that while the heat exchanger tube is in the horizontal position, the PCM has more effective and steady phase change characteristics than in the vertical position. The heat storage capacity of the container (PCM tube) is not as good as we expected in this study and the average heat storage efficiency (or heat exchanger effectiveness) is 54%. It means that 46% of the heat acrually lost somewhere.
Guruprasad Alva - One of the best experts on this subject based on the ideXlab platform.
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microencapsulation and thermal properties of Myristic Acid with ethyl cellulose shell for thermal energy storage
Applied Energy, 2018Co-Authors: Guruprasad Alva, Guiyin FangAbstract:Abstract Encapsulating phase change material (PCM) is an effective way to avoid leakage and prevent contact with external environment. In this work, Myristic Acid (MA) was used as PCM to store and release latent heat through solid–liquid phase change and ethyl cellulose (EC) was employed as shell to microencapsulate MA for preventing the leakage of melted MA. The novel microencapsulated phase change materials (MPCMs) with MA core and EC shell were fabricated by emulsification–solvent evaporation method. The morphology and particle size of the MPCMs were measured by scanning electronic microscope (SEM), and similar and complete spheres were observed. Chemical structure and crystal phase of MPCMs were analyzed by Fourier transformation infrared spectroscope (FT–IR) and X–ray diffractometer (XRD), finding that EC and MA are well combined by physical action without chemical reaction. Thermogravimetric analyzer (TGA) was used to investigate the thermal stability, and the results revealed that MPPCMs possess excellent thermal stability at working temperature. The thermal cycling tests indicated that the MPCM have excellent thermal reliability. Differential scanning calorimeter (DSC) was employed to analyze the thermal properties of MPCMs. The most satisfying sample is MCPM1 with phase change enthalpy of 122.61 J/g and phase change temperature of 53.32 °C. Hence, the application of the prepared MPCMs in low–temperature solar energy systems has great potential in the future.
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synthesis and characterization of microencapsulated Myristic Acid palmitic Acid eutectic mixture as phase change material for thermal energy storage
Applied Energy, 2017Co-Authors: Guruprasad Alva, Xiang Huang, Lingkun Liu, Guiyin FangAbstract:In this work microencapsulation of Myristic Acid–palmitic Acid (MA–PA) eutectic mixture with silica shell using sol−gel method has been attempted. The core phase change material (PCM) for thermal energy storage was Myristic Acid−palmitic Acid eutectic mixture and the shell material to prevent the PCM core from leakage was silica prepared from methyl triethoxysilane (MTES). Thermal properties of the microcapsules were measured by differential scanning calorimeter (DSC). The morphology and particle size of the microcapsules were examined by scanning electronic microscope (SEM). Fourier transformation infrared spectrophotometer (FT–IR) and X–ray diffractometer (XRD) were used to investigate the chemical structure and crystalloid phase of the microcapsules respectively. The DSC results indicated that microencapsulated phase change material (MPCM) melts at 46.08°C with a latent heat of 169.69kJkg−1 and solidifies at 44.35°C with a latent heat of 159.59kJkg−1. The thermal stability of the microcapsules was analyzed by a thermogravimeter (TGA). The results indicated that the MPCM has good thermal stability and is suitable for thermal energy storage application.
