The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Simon Furbo - One of the best experts on this subject based on the ideXlab platform.
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Laboratory Test of a Cylindrical Heat Storage Module with Water and Sodium Acetate Trihydrate
Energy Procedia, 2016Co-Authors: Mark Dannemand, Jakob Berg Johansen, Weiqiang Kong, Simon FurboAbstract:Abstract Cylindrical heat storage modules with internal heat exchangers have been tested in a laboratory. The modules were filled with water and Sodium Acetate trihydrate with additives. The testing focused on the heat content of the storage material and the heat exchange capacity rate during charge of the module. For the tests with the phase change materials, the focus was furthermore on the stability of supercooling and cycling stability. Testing the module with Sodium Acetate trihydrate and 6.4% extra water showed that phase separation increased and the heat released after solidification of supercooled phase change material was reduced over 17 test cycles. The heat released after solidification of the supercooled Sodium Acetate trihydrate with thickening agent and graphite was stable over the test cycles. Stable supercooling was obtained in 7 out of 17 test cycles with the module with Sodium Acetate trihydrate with extra water and in 6 out of 35 test cycles for the module with thickening agent.
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Experimental investigations on heat content of supercooled Sodium Acetate trihydrate by a simple heat loss method
Solar Energy, 2016Co-Authors: Weiqiang Kong, Mark Dannemand, Jakob Berg Johansen, Jianhua Fan, Janne Dragsted, Gerald Englmair, Simon FurboAbstract:Abstract Sodium Acetate trihydrate is a phase change material that can be used for long term heat storage in solar heating systems because of its relatively high heat of fusion, a melting temperature of 58 °C and its ability to supercool stable. In practical applications Sodium Acetate trihydrate tend to suffer from phase separation which is the phenomenon where anhydrous salt settles to the bottom over time. This happens especially in supercooled state. The heat released from the crystallization of supercooled Sodium Acetate trihydrate with phase separation will be lower than the heat released from Sodium Acetate trihydrate without phase separation. Possible ways of avoiding or reducing the problem of phase separation were investigated. A wide variety of composites of Sodium Acetate trihydrate with additives including extra water, thickening agents, solid and liquid polymers have been experimentally investigated by a simple heat loss method. The aim was to find compositions of maximum heat released from the crystallization of supercooled Sodium Acetate trihydrate samples at ambient temperature. It was found that samples of Sodium Acetate trihydrate with 0.5–2% (wt.%) Carboxy-Methyl Cellulose, 0.3–0.5 % (wt.%) Xanthan Gum or 1–2% (wt.%) of some solid or liquid polymers as additives had significantly higher heat contents compared to samples of Sodium Acetate trihydrate suffering from phase separation.
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Long term thermal energy storage with stable supercooled Sodium Acetate trihydrate
Applied Thermal Engineering, 2015Co-Authors: Mark Dannemand, Jorgen Munthe Schultz, Jakob Berg Johansen, Simon FurboAbstract:Abstract Utilizing stable supercooling of Sodium Acetate trihydrate makes it possible to store thermal energy partly loss free. This principle makes seasonal heat storage in compact systems possible. To keep high and stable energy content and cycling stability phase separation of the storage material must be avoided. This can be done by the use of the thickening agents carboxymethyl cellulose or xanthan rubber. Stable supercooling requires that the Sodium Acetate trihydrate is heated to a temperature somewhat higher than the melting temperature of 58 °C before it cools down. As the phase change material melts it expands and will cause a pressure built up in a closed chamber which might compromise stability of the supercooling. This can be avoided by having an air volume above the phase change material connected to an external pressure less expansion tank. Supercooled Sodium Acetate trihydrate at 20 °C stores up to 230 kJ/kg. TRNSYS simulations of a solar combi system including a storage with four heat storage modules of each 200 kg of Sodium Acetate trihydrate utilizing stable supercooling achieved a solar fraction of 80% for a low energy house in Danish climatic conditions.
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development of seasonal heat storage based on stable supercooling of a Sodium Acetate water mixture
Energy Procedia, 2012Co-Authors: Simon Furbo, Jianhua Fan, Elsa Andersen, Ziqian Chen, Bengt PerersAbstract:Abstract A number of heat storage modules for seasonal heat storages based on stable supercooling of a Sodium Acetate water mixture have been tested by means of experiments in a heat storage test facility. The modules had different volumes and designs. Further, different methods were used to transfer heat to and from the Sodium Acetate water mixture in the modules.By means of the experiments: • The heat exchange capacity rates to and from the Sodium Acetate water mixture in the heat storage modules were determined for different volume flow rates. • The heat content of the heat storage modules were determined. • The reliability of the supercooling was elucidated for the heat storage modules for different operation conditions. • The reliability of a cooling method used to start solidification of the supercooled Sodium Acetate water mixture was elucidated. The method is making use of boiling CO2 in a small tank in good thermal contact with the outer surface of the heat storage module. • Experience on operation of the heat storage modules was gained. Based on the investigations recommendations for future development of a seasonal heat storage based on stable supercooling of a Sodium Acetate water mixture are given.
Mark Dannemand - One of the best experts on this subject based on the ideXlab platform.
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Laboratory Test of a Cylindrical Heat Storage Module with Water and Sodium Acetate Trihydrate
Energy Procedia, 2016Co-Authors: Mark Dannemand, Jakob Berg Johansen, Weiqiang Kong, Simon FurboAbstract:Abstract Cylindrical heat storage modules with internal heat exchangers have been tested in a laboratory. The modules were filled with water and Sodium Acetate trihydrate with additives. The testing focused on the heat content of the storage material and the heat exchange capacity rate during charge of the module. For the tests with the phase change materials, the focus was furthermore on the stability of supercooling and cycling stability. Testing the module with Sodium Acetate trihydrate and 6.4% extra water showed that phase separation increased and the heat released after solidification of supercooled phase change material was reduced over 17 test cycles. The heat released after solidification of the supercooled Sodium Acetate trihydrate with thickening agent and graphite was stable over the test cycles. Stable supercooling was obtained in 7 out of 17 test cycles with the module with Sodium Acetate trihydrate with extra water and in 6 out of 35 test cycles for the module with thickening agent.
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Experimental investigations on heat content of supercooled Sodium Acetate trihydrate by a simple heat loss method
Solar Energy, 2016Co-Authors: Weiqiang Kong, Mark Dannemand, Jakob Berg Johansen, Jianhua Fan, Janne Dragsted, Gerald Englmair, Simon FurboAbstract:Abstract Sodium Acetate trihydrate is a phase change material that can be used for long term heat storage in solar heating systems because of its relatively high heat of fusion, a melting temperature of 58 °C and its ability to supercool stable. In practical applications Sodium Acetate trihydrate tend to suffer from phase separation which is the phenomenon where anhydrous salt settles to the bottom over time. This happens especially in supercooled state. The heat released from the crystallization of supercooled Sodium Acetate trihydrate with phase separation will be lower than the heat released from Sodium Acetate trihydrate without phase separation. Possible ways of avoiding or reducing the problem of phase separation were investigated. A wide variety of composites of Sodium Acetate trihydrate with additives including extra water, thickening agents, solid and liquid polymers have been experimentally investigated by a simple heat loss method. The aim was to find compositions of maximum heat released from the crystallization of supercooled Sodium Acetate trihydrate samples at ambient temperature. It was found that samples of Sodium Acetate trihydrate with 0.5–2% (wt.%) Carboxy-Methyl Cellulose, 0.3–0.5 % (wt.%) Xanthan Gum or 1–2% (wt.%) of some solid or liquid polymers as additives had significantly higher heat contents compared to samples of Sodium Acetate trihydrate suffering from phase separation.
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Long term thermal energy storage with stable supercooled Sodium Acetate trihydrate
Applied Thermal Engineering, 2015Co-Authors: Mark Dannemand, Jorgen Munthe Schultz, Jakob Berg Johansen, Simon FurboAbstract:Abstract Utilizing stable supercooling of Sodium Acetate trihydrate makes it possible to store thermal energy partly loss free. This principle makes seasonal heat storage in compact systems possible. To keep high and stable energy content and cycling stability phase separation of the storage material must be avoided. This can be done by the use of the thickening agents carboxymethyl cellulose or xanthan rubber. Stable supercooling requires that the Sodium Acetate trihydrate is heated to a temperature somewhat higher than the melting temperature of 58 °C before it cools down. As the phase change material melts it expands and will cause a pressure built up in a closed chamber which might compromise stability of the supercooling. This can be avoided by having an air volume above the phase change material connected to an external pressure less expansion tank. Supercooled Sodium Acetate trihydrate at 20 °C stores up to 230 kJ/kg. TRNSYS simulations of a solar combi system including a storage with four heat storage modules of each 200 kg of Sodium Acetate trihydrate utilizing stable supercooling achieved a solar fraction of 80% for a low energy house in Danish climatic conditions.
Hiroshi Takagi - One of the best experts on this subject based on the ideXlab platform.
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Sodium Acetate Responses in Saccharomyces cerevisiae and the Ubiquitin Ligase Rsp5.
Frontiers in microbiology, 2018Co-Authors: Akaraphol Watcharawipas, Daisuke Watanabe, Hiroshi TakagiAbstract:Recent studies have revealed the feasibility of Sodium Acetate as a potentially novel inhibitor/stressor relevant to the fermentation from neutralized lignocellulosic hydrolysates. This mini-review focuses on the toxicity of Sodium Acetate, which is composed of both Sodium and Acetate ions, and on the involved cellular responses that it elicits, particularly via the high-osmolarity glycerol (HOG) pathway, the Rim101 pathway, the P-type ATPase Sodium pumps Ena1/2/5, and the ubiquitin ligase Rsp5 with its adaptors. Increased understanding of cellular responses to Sodium Acetate would improve our understanding of how cells respond not only to different stimuli but also to composite stresses induced by multiple components (e.g., Sodium and Acetate) simultaneously. Moreover, unraveling the characteristics of specific stresses under industrially related conditions and the cellular responses evoked by these stresses would be a key factor in the industrial yeast strain engineering toward the increased productivity of not only bioethanol but also advanced biofuels and valuable chemicals that will be in demand in the coming era of bio-based industry.
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Enhanced Sodium Acetate tolerance in Saccharomyces cerevisiae by the Thr255Ala mutation of the ubiquitin ligase Rsp5.
FEMS yeast research, 2017Co-Authors: Akaraphol Watcharawipas, Daisuke Watanabe, Hiroshi TakagiAbstract:Sodium and Acetate inhibit cell growth and ethanol fermentation by different mechanisms in Saccharomyces cerevisiae. We identified the substitution of a conserved Thr255 to Ala (T255A) in the essential Nedd4-family ubiquitin ligase Rsp5, which enhances cellular Sodium Acetate tolerance. The T255A mutation selectively increased the resistance of cells against Sodium Acetate, suggesting that S. cerevisiae cells possess an Rsp5-mediated mechanism to cope with the composite stress of Sodium and Acetate. The Sodium Acetate tolerance was dependent on the extrusion of intracellular Sodium ions by the plasma membrane-localized Sodium pumps Ena1, Ena2, and Ena5 (Ena1/2/5) and two known upstream regulators: the Rim101 pH signaling pathway and the Hog1 mitogen-activated protein kinase. However, the T255A mutation affected neither the ubiquitination level of the Rsp5 adaptor protein Rim8 nor the phosphorylation level of Hog1. These data raised the possibility that Rsp5 enhances the function of Ena1/2/5 specifically in response to Sodium Acetate through an unknown mechanism other than ubiquitination of Rim8 and activation of Hog1-mediated signaling. Also, an industrial yeast strain that expresses the T255A variant exhibited increased initial fermentation rates in the presence of Sodium Acetate. Hence, this mutation has potential for the improvement of bioethanol production from lignocellulosic biomass.
Jakob Berg Johansen - One of the best experts on this subject based on the ideXlab platform.
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Laboratory Test of a Cylindrical Heat Storage Module with Water and Sodium Acetate Trihydrate
Energy Procedia, 2016Co-Authors: Mark Dannemand, Jakob Berg Johansen, Weiqiang Kong, Simon FurboAbstract:Abstract Cylindrical heat storage modules with internal heat exchangers have been tested in a laboratory. The modules were filled with water and Sodium Acetate trihydrate with additives. The testing focused on the heat content of the storage material and the heat exchange capacity rate during charge of the module. For the tests with the phase change materials, the focus was furthermore on the stability of supercooling and cycling stability. Testing the module with Sodium Acetate trihydrate and 6.4% extra water showed that phase separation increased and the heat released after solidification of supercooled phase change material was reduced over 17 test cycles. The heat released after solidification of the supercooled Sodium Acetate trihydrate with thickening agent and graphite was stable over the test cycles. Stable supercooling was obtained in 7 out of 17 test cycles with the module with Sodium Acetate trihydrate with extra water and in 6 out of 35 test cycles for the module with thickening agent.
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Experimental investigations on heat content of supercooled Sodium Acetate trihydrate by a simple heat loss method
Solar Energy, 2016Co-Authors: Weiqiang Kong, Mark Dannemand, Jakob Berg Johansen, Jianhua Fan, Janne Dragsted, Gerald Englmair, Simon FurboAbstract:Abstract Sodium Acetate trihydrate is a phase change material that can be used for long term heat storage in solar heating systems because of its relatively high heat of fusion, a melting temperature of 58 °C and its ability to supercool stable. In practical applications Sodium Acetate trihydrate tend to suffer from phase separation which is the phenomenon where anhydrous salt settles to the bottom over time. This happens especially in supercooled state. The heat released from the crystallization of supercooled Sodium Acetate trihydrate with phase separation will be lower than the heat released from Sodium Acetate trihydrate without phase separation. Possible ways of avoiding or reducing the problem of phase separation were investigated. A wide variety of composites of Sodium Acetate trihydrate with additives including extra water, thickening agents, solid and liquid polymers have been experimentally investigated by a simple heat loss method. The aim was to find compositions of maximum heat released from the crystallization of supercooled Sodium Acetate trihydrate samples at ambient temperature. It was found that samples of Sodium Acetate trihydrate with 0.5–2% (wt.%) Carboxy-Methyl Cellulose, 0.3–0.5 % (wt.%) Xanthan Gum or 1–2% (wt.%) of some solid or liquid polymers as additives had significantly higher heat contents compared to samples of Sodium Acetate trihydrate suffering from phase separation.
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Long term thermal energy storage with stable supercooled Sodium Acetate trihydrate
Applied Thermal Engineering, 2015Co-Authors: Mark Dannemand, Jorgen Munthe Schultz, Jakob Berg Johansen, Simon FurboAbstract:Abstract Utilizing stable supercooling of Sodium Acetate trihydrate makes it possible to store thermal energy partly loss free. This principle makes seasonal heat storage in compact systems possible. To keep high and stable energy content and cycling stability phase separation of the storage material must be avoided. This can be done by the use of the thickening agents carboxymethyl cellulose or xanthan rubber. Stable supercooling requires that the Sodium Acetate trihydrate is heated to a temperature somewhat higher than the melting temperature of 58 °C before it cools down. As the phase change material melts it expands and will cause a pressure built up in a closed chamber which might compromise stability of the supercooling. This can be avoided by having an air volume above the phase change material connected to an external pressure less expansion tank. Supercooled Sodium Acetate trihydrate at 20 °C stores up to 230 kJ/kg. TRNSYS simulations of a solar combi system including a storage with four heat storage modules of each 200 kg of Sodium Acetate trihydrate utilizing stable supercooling achieved a solar fraction of 80% for a low energy house in Danish climatic conditions.
Akaraphol Watcharawipas - One of the best experts on this subject based on the ideXlab platform.
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Sodium Acetate Responses in Saccharomyces cerevisiae and the Ubiquitin Ligase Rsp5.
Frontiers in microbiology, 2018Co-Authors: Akaraphol Watcharawipas, Daisuke Watanabe, Hiroshi TakagiAbstract:Recent studies have revealed the feasibility of Sodium Acetate as a potentially novel inhibitor/stressor relevant to the fermentation from neutralized lignocellulosic hydrolysates. This mini-review focuses on the toxicity of Sodium Acetate, which is composed of both Sodium and Acetate ions, and on the involved cellular responses that it elicits, particularly via the high-osmolarity glycerol (HOG) pathway, the Rim101 pathway, the P-type ATPase Sodium pumps Ena1/2/5, and the ubiquitin ligase Rsp5 with its adaptors. Increased understanding of cellular responses to Sodium Acetate would improve our understanding of how cells respond not only to different stimuli but also to composite stresses induced by multiple components (e.g., Sodium and Acetate) simultaneously. Moreover, unraveling the characteristics of specific stresses under industrially related conditions and the cellular responses evoked by these stresses would be a key factor in the industrial yeast strain engineering toward the increased productivity of not only bioethanol but also advanced biofuels and valuable chemicals that will be in demand in the coming era of bio-based industry.
-
Enhanced Sodium Acetate tolerance in Saccharomyces cerevisiae by the Thr255Ala mutation of the ubiquitin ligase Rsp5.
FEMS yeast research, 2017Co-Authors: Akaraphol Watcharawipas, Daisuke Watanabe, Hiroshi TakagiAbstract:Sodium and Acetate inhibit cell growth and ethanol fermentation by different mechanisms in Saccharomyces cerevisiae. We identified the substitution of a conserved Thr255 to Ala (T255A) in the essential Nedd4-family ubiquitin ligase Rsp5, which enhances cellular Sodium Acetate tolerance. The T255A mutation selectively increased the resistance of cells against Sodium Acetate, suggesting that S. cerevisiae cells possess an Rsp5-mediated mechanism to cope with the composite stress of Sodium and Acetate. The Sodium Acetate tolerance was dependent on the extrusion of intracellular Sodium ions by the plasma membrane-localized Sodium pumps Ena1, Ena2, and Ena5 (Ena1/2/5) and two known upstream regulators: the Rim101 pH signaling pathway and the Hog1 mitogen-activated protein kinase. However, the T255A mutation affected neither the ubiquitination level of the Rsp5 adaptor protein Rim8 nor the phosphorylation level of Hog1. These data raised the possibility that Rsp5 enhances the function of Ena1/2/5 specifically in response to Sodium Acetate through an unknown mechanism other than ubiquitination of Rim8 and activation of Hog1-mediated signaling. Also, an industrial yeast strain that expresses the T255A variant exhibited increased initial fermentation rates in the presence of Sodium Acetate. Hence, this mutation has potential for the improvement of bioethanol production from lignocellulosic biomass.
