Thermal energy storage(TES)solutions offer opportunities to reduce energy consumption,greenhouse gas emissions,and cost.Specifically,they can help reduce the peak load and address the intermittency of renewable energy...Thermal energy storage(TES)solutions offer opportunities to reduce energy consumption,greenhouse gas emissions,and cost.Specifically,they can help reduce the peak load and address the intermittency of renewable energy sources by time shifting the load,which are critical toward zero energy buildings.Thermochemical materials(TCMs)as a class of TES undergo a solid-gas reversible chemical reaction with water vapor to store and release energy with high storage capacities(600 kWh m^(-3))and negligible self-discharge that makes them uniquely suited as compact,stand-alone units for daily or seasonal storage.However,TCMs suffer from instabilities at the material(salt particles)and reactor level(packed beds of salt),resulting in poor multi-cycle efficiency and high-levelized cost of storage.In this study,a model is developed to predict the pulverization limit or Rcrit of various salt hydrates during thermal cycling.This is critical as it provides design rules to make mechanically stable TCM composites as well as enables the use of more energy-efficient manufacturing process(solid-state mixing)to make the composites.The model is experimentally validated on multiple TCM salt hydrates with different water content,and effect of Rcrit on hydration and dehydration kinetics is also investigated.展开更多
The huge volumes of crop residues generated during the production,processing,and consumption of farm products constitute an ecological nuisance when ineffectively managed.The conversion of crop residues to green hydro...The huge volumes of crop residues generated during the production,processing,and consumption of farm products constitute an ecological nuisance when ineffectively managed.The conversion of crop residues to green hydrogen is one of the sustainable management strategies for ubiquitous crop residues.Production of green hydrogen from crop residue sources will contribute to deepening access to clean and affordable energy,mitigating climate change,and ensuring environmental sustainability.However,the deployment of conventional thermochemical technologies for the conversion of crop residues to green hydrogen is costly,requires long residence time,produces low-quality products,and therefore needs to be upgraded.The current review examines the conventional,advanced,and integrated thermochemical conversion technologies for crop residues for green hydrogen production.After a brief overview of the conventional thermochemical techniques,the review delves into the broad narration of advanced thermochemical technologies including catalytic pyrolysis,microwave pyrolysis,co-pyrolysis,hyropyrolysis,and autothermal pyrolysis.The study advocates the deployment of integrated pyrolysis,anaerobic digestion,pyrolysis,and gasification technologies will ensure scalability,decomposition of recalcitrant feedstocks,and generation of high grade green hydrogen.The outlook provides suggestions for future research into cost-saving and sustainable integrated technologies for green hydrogen production towards achieving carbon neutrality and a circular bio-economy.展开更多
热化学储能(thermochemical energy storage,TCES)技术是未来可再生能源社会最具前景的技术之一。Ca(OH)_(2)/CaO TCES体系因其储能密度较高、环境友好、廉价等特点受到人们的广泛关注。本工作建立了一个直接与间接混合加热的固定床反...热化学储能(thermochemical energy storage,TCES)技术是未来可再生能源社会最具前景的技术之一。Ca(OH)_(2)/CaO TCES体系因其储能密度较高、环境友好、廉价等特点受到人们的广泛关注。本工作建立了一个直接与间接混合加热的固定床反应器实验平台,进行了空气氛围下的储/释热实验,探究了混合加热反应器内的储热特性与限制因素,并在此基础上探究了在反应器尺度改善循环性能的可行方案。实验研究表明,采用直接与间接混合加热的方式,使得反应呈现向心推进与逐层推进相结合的形式,增进了储能反应的速率;反应性能随着循环次数增多逐渐下降,5次循环后的储能反应最大转化率降低了5.6%,10次循环相较于5次循环的反应最大转化率降低了3.8%。TG实验与粒径测试结果表明,空气中CO_(2)是造成循环性能下降的主要因素;提高脱水温度可以有效恢复循环性能,650℃时所提供的过余温度可以有效降低反应物中CaCO_(3)的含量。展开更多
从中草药荷叶、黄连根、黄藤、十大功劳中分别提取出荷叶碱、黄连素、黄藤素、异汉防己碱,并对其进行了表征。用瑞典产八通道微量量热仪(3114/3236 TAM Air)测定了不同浓度的生物碱在不同温度时对大肠杆菌、金黄色葡萄球菌、枯草杆菌代...从中草药荷叶、黄连根、黄藤、十大功劳中分别提取出荷叶碱、黄连素、黄藤素、异汉防己碱,并对其进行了表征。用瑞典产八通道微量量热仪(3114/3236 TAM Air)测定了不同浓度的生物碱在不同温度时对大肠杆菌、金黄色葡萄球菌、枯草杆菌代谢作用的热功率-时间曲线,计算出细菌生长的速率常数,建立速率常数与生物碱浓度的方程式、细菌生长速率常数与温度的方程式,进而确定了最佳抑菌浓度和细菌最佳生长温度。展开更多
The inclusion complexes formation of dipfluzine(DF)with hydroxpropy-β-cyclodextrin(HP-β-CD)in aqueous solution was investigated by the phase-solubility method.With the increase of HP-β-CD concentration in aqueous s...The inclusion complexes formation of dipfluzine(DF)with hydroxpropy-β-cyclodextrin(HP-β-CD)in aqueous solution was investigated by the phase-solubility method.With the increase of HP-β-CD concentration in aqueous sloutions,the solubility of DF increased linearly,which showed typical AL-type phase solubility diagram.The molar ratio of the DF-HP-β-CD complex was 1∶1.The effect of temperature on the reaction was studied through thermodynamics.The apparent stability constants of inclusion reation were determined.Thermodynamic parameters during the inclusion process were as follows: △rH=30.58 kJ·mol-1,△rS=158.8 J·mol-1·K-1,△rG<0.The complex process was endothermic and spontaneous.With the increase of temperature,the tendency of spontaneous reaction increased.展开更多
基金supported by the Energy Efficiency and Renewable Energy,Building Technologies Program,of the US Department of Energy,under contract no.DE-AC02-05CH11231the support on the DSC/TGA 3+supported by the Office of Science,Office of Basic Energy Sciences,of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231
文摘Thermal energy storage(TES)solutions offer opportunities to reduce energy consumption,greenhouse gas emissions,and cost.Specifically,they can help reduce the peak load and address the intermittency of renewable energy sources by time shifting the load,which are critical toward zero energy buildings.Thermochemical materials(TCMs)as a class of TES undergo a solid-gas reversible chemical reaction with water vapor to store and release energy with high storage capacities(600 kWh m^(-3))and negligible self-discharge that makes them uniquely suited as compact,stand-alone units for daily or seasonal storage.However,TCMs suffer from instabilities at the material(salt particles)and reactor level(packed beds of salt),resulting in poor multi-cycle efficiency and high-levelized cost of storage.In this study,a model is developed to predict the pulverization limit or Rcrit of various salt hydrates during thermal cycling.This is critical as it provides design rules to make mechanically stable TCM composites as well as enables the use of more energy-efficient manufacturing process(solid-state mixing)to make the composites.The model is experimentally validated on multiple TCM salt hydrates with different water content,and effect of Rcrit on hydration and dehydration kinetics is also investigated.
文摘The huge volumes of crop residues generated during the production,processing,and consumption of farm products constitute an ecological nuisance when ineffectively managed.The conversion of crop residues to green hydrogen is one of the sustainable management strategies for ubiquitous crop residues.Production of green hydrogen from crop residue sources will contribute to deepening access to clean and affordable energy,mitigating climate change,and ensuring environmental sustainability.However,the deployment of conventional thermochemical technologies for the conversion of crop residues to green hydrogen is costly,requires long residence time,produces low-quality products,and therefore needs to be upgraded.The current review examines the conventional,advanced,and integrated thermochemical conversion technologies for crop residues for green hydrogen production.After a brief overview of the conventional thermochemical techniques,the review delves into the broad narration of advanced thermochemical technologies including catalytic pyrolysis,microwave pyrolysis,co-pyrolysis,hyropyrolysis,and autothermal pyrolysis.The study advocates the deployment of integrated pyrolysis,anaerobic digestion,pyrolysis,and gasification technologies will ensure scalability,decomposition of recalcitrant feedstocks,and generation of high grade green hydrogen.The outlook provides suggestions for future research into cost-saving and sustainable integrated technologies for green hydrogen production towards achieving carbon neutrality and a circular bio-economy.
文摘热化学储能(thermochemical energy storage,TCES)技术是未来可再生能源社会最具前景的技术之一。Ca(OH)_(2)/CaO TCES体系因其储能密度较高、环境友好、廉价等特点受到人们的广泛关注。本工作建立了一个直接与间接混合加热的固定床反应器实验平台,进行了空气氛围下的储/释热实验,探究了混合加热反应器内的储热特性与限制因素,并在此基础上探究了在反应器尺度改善循环性能的可行方案。实验研究表明,采用直接与间接混合加热的方式,使得反应呈现向心推进与逐层推进相结合的形式,增进了储能反应的速率;反应性能随着循环次数增多逐渐下降,5次循环后的储能反应最大转化率降低了5.6%,10次循环相较于5次循环的反应最大转化率降低了3.8%。TG实验与粒径测试结果表明,空气中CO_(2)是造成循环性能下降的主要因素;提高脱水温度可以有效恢复循环性能,650℃时所提供的过余温度可以有效降低反应物中CaCO_(3)的含量。
文摘从中草药荷叶、黄连根、黄藤、十大功劳中分别提取出荷叶碱、黄连素、黄藤素、异汉防己碱,并对其进行了表征。用瑞典产八通道微量量热仪(3114/3236 TAM Air)测定了不同浓度的生物碱在不同温度时对大肠杆菌、金黄色葡萄球菌、枯草杆菌代谢作用的热功率-时间曲线,计算出细菌生长的速率常数,建立速率常数与生物碱浓度的方程式、细菌生长速率常数与温度的方程式,进而确定了最佳抑菌浓度和细菌最佳生长温度。
文摘The inclusion complexes formation of dipfluzine(DF)with hydroxpropy-β-cyclodextrin(HP-β-CD)in aqueous solution was investigated by the phase-solubility method.With the increase of HP-β-CD concentration in aqueous sloutions,the solubility of DF increased linearly,which showed typical AL-type phase solubility diagram.The molar ratio of the DF-HP-β-CD complex was 1∶1.The effect of temperature on the reaction was studied through thermodynamics.The apparent stability constants of inclusion reation were determined.Thermodynamic parameters during the inclusion process were as follows: △rH=30.58 kJ·mol-1,△rS=158.8 J·mol-1·K-1,△rG<0.The complex process was endothermic and spontaneous.With the increase of temperature,the tendency of spontaneous reaction increased.
