期刊：
Renewable & Sustainable Energy Reviews,2026年226:116230 ISSN：1364-0321
通讯作者：
Chuanchang Li
作者机构：
[Xinrui Yan; Baoshan Xie; Chuanchang Li] Key Laboratory of Renewable Energy Electric-Technology of Hunan Province, School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, 410114, China
通讯机构：
[Chuanchang Li] K;Key Laboratory of Renewable Energy Electric-Technology of Hunan Province, School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, 410114, China
摘要：
With the ongoing advancement of aerospace technology, the demand for high-performance materials is rising. Phase change materials (PCMs), known for their unique thermophysical properties and versatility, offer new opportunities for breakthroughs in aerospace applications. PCMs, characterized by their low density, high energy storage density, and robust cycle stability, are ideal for aircraft lightweighting and thermal management of electronic devices. This review provides an overview of PCMs, including their mechanism, classification, preparation methods, and performance optimization. It then outlines the selection criteria for aerospace applications, emphasizing attributes such as lightweight design, long-term cycle stability, high thermal conductivity, resistance to extreme temperatures and radiation, and compatibility with existing equipment. Finally, the review explores recent advancements in PCM applications in aerospace, addressing the associated challenges and future prospects.
With the ongoing advancement of aerospace technology, the demand for high-performance materials is rising. Phase change materials (PCMs), known for their unique thermophysical properties and versatility, offer new opportunities for breakthroughs in aerospace applications. PCMs, characterized by their low density, high energy storage density, and robust cycle stability, are ideal for aircraft lightweighting and thermal management of electronic devices. This review provides an overview of PCMs, including their mechanism, classification, preparation methods, and performance optimization. It then outlines the selection criteria for aerospace applications, emphasizing attributes such as lightweight design, long-term cycle stability, high thermal conductivity, resistance to extreme temperatures and radiation, and compatibility with existing equipment. Finally, the review explores recent advancements in PCM applications in aerospace, addressing the associated challenges and future prospects.
作者机构：
[Shan Cheng; Kehui Yao; Linxi Guo; Zihui Xu; Hong Tian] School of Energy and Power Engineering, Key Laboratory of Renewable Energy Electric-Technology of Hunan Province, Changsha University of Science and Technology, Changsha 410114, China;State Grid Hunan Electric Power Company Limited Research Institute, Changsha 410208, China;Hunan Key Laboratory of Clean & Efficient Power Generation Technologies, Changsha 410208, China;[Wen Chen] State Grid Hunan Electric Power Company Limited Research Institute, Changsha 410208, China<&wdkj&>Hunan Key Laboratory of Clean & Efficient Power Generation Technologies, Changsha 410208, China
通讯机构：
[Hong Tian] S;School of Energy and Power Engineering, Key Laboratory of Renewable Energy Electric-Technology of Hunan Province, Changsha University of Science and Technology, Changsha 410114, China
摘要：
Pyrolysis of sludge is a promising method for energy and resource recovery from solid waste. However, the emission of odorous gases, especially those containing sulfur and nitrogen, poses significant environmental challenges. Therefore, this study investigated the release characteristics of organic sulfur, when it coexist with organic nitrogen. Focusing on the mechanism by which organic nitrogen affects the transformation pathways of organic sulfur. Co-pyrolysis experiments with organic sulfur model compounds ‘benzyl sulfide (BS) and 4,4′-dihydroxydiphenyl sulfide (DHS)’ and nitrogen-containing model compounds ‘proline (Pro) and aspartic acid (Asp)’. The presence of Pro and Asp lower the pyrolysis temperature and enhance the reaction extent of BS and DHS. The functional groups of organic nitrogen compounds, such as −H, –OH, and −C=O, promoted the production of sulfur-containing gases from organic sulfur compounds. Pro and Asp increase the yield of gas-S by 1.5 ∼ 2 times and 3 times, respectively. Pro also reduced the energy barriers for key steps in H 2 S formation from BS, including the removal of −SH radical from benzyl mercaptan and thiophenol, and −SH hydrogenation, by 83.92 kJ/mol, 39.97 kJ/mol, and 135 kJ/mol, respectively. Asp promoted the cleavage of the C aliphatic -S bond in BS and the C aromatic -S bond in DHS, lowering the energy barriers by 74.05 kJ/mol and 160.27 kJ/mol, respectively. These findings elucidate the role of organic nitrogen compounds in organic sulfur release during sewage sludge pyrolysis, thereby providing a potential way for the synergistic removal of sulfur- and nitrogen-containing odorous gases.
Pyrolysis of sludge is a promising method for energy and resource recovery from solid waste. However, the emission of odorous gases, especially those containing sulfur and nitrogen, poses significant environmental challenges. Therefore, this study investigated the release characteristics of organic sulfur, when it coexist with organic nitrogen. Focusing on the mechanism by which organic nitrogen affects the transformation pathways of organic sulfur. Co-pyrolysis experiments with organic sulfur model compounds ‘benzyl sulfide (BS) and 4,4′-dihydroxydiphenyl sulfide (DHS)’ and nitrogen-containing model compounds ‘proline (Pro) and aspartic acid (Asp)’. The presence of Pro and Asp lower the pyrolysis temperature and enhance the reaction extent of BS and DHS. The functional groups of organic nitrogen compounds, such as −H, –OH, and −C=O, promoted the production of sulfur-containing gases from organic sulfur compounds. Pro and Asp increase the yield of gas-S by 1.5 ∼ 2 times and 3 times, respectively. Pro also reduced the energy barriers for key steps in H 2 S formation from BS, including the removal of −SH radical from benzyl mercaptan and thiophenol, and −SH hydrogenation, by 83.92 kJ/mol, 39.97 kJ/mol, and 135 kJ/mol, respectively. Asp promoted the cleavage of the C aliphatic -S bond in BS and the C aromatic -S bond in DHS, lowering the energy barriers by 74.05 kJ/mol and 160.27 kJ/mol, respectively. These findings elucidate the role of organic nitrogen compounds in organic sulfur release during sewage sludge pyrolysis, thereby providing a potential way for the synergistic removal of sulfur- and nitrogen-containing odorous gases.
期刊：
International Journal of Heat and Fluid Flow,2026年117:110035 ISSN：0142-727X
通讯作者：
Yanfeng Yang
作者机构：
[Chaolin Liu; Chaofan Xiao] School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, China;[Sanqi Liu] Chengnan College, Changsha University of Science and Technology, Changsha 410015, China;Hebei Key Laboratory of Physics and Energy Technology, Baoding 071003, China;[Yanfeng Yang] School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, China<&wdkj&>Hebei Key Laboratory of Physics and Energy Technology, Baoding 071003, China
通讯机构：
[Yanfeng Yang] S;School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, China<&wdkj&>Hebei Key Laboratory of Physics and Energy Technology, Baoding 071003, China
摘要：
In this study, a two-dimensional cylindrical tube array model was established using the finite element method. The effects of sound wave frequency (50–200 Hz) and sound pressure level (118–140 dB) on the flow characteristics in the inter-tube gap under laminar ( Re = 150) and turbulent ( Re = 500) conditions were systematically investigated. The results show that under laminar conditions, the average gap flow velocity increases from 0.025 m/s to 0.048 m/s when the sound pressure level rises from 118 dB to 130 dB at a 50 Hz sound wave, representing a 177 % increase. However, at a constant sound pressure level of 130 dB, the flow velocity of the front row tubes (C1-C7) significantly decreases as the frequency increases from 50 Hz to 200 Hz. Under turbulent conditions, the flow velocity increases linearly by 33 % within the range of 130–140 dB at 50 Hz sound waves. Even though the flow velocity decreases when the frequency increases to 140 dB sound pressure, it is still higher than that without sound waves. The study found that low-frequency sound waves have a more significant effect on enhancing the flow of the front row tubes, while high-frequency sound waves need to consider energy dissipation. Overall, low-frequency and high sound pressure level sound waves can effectively increase the inter-tube flow velocity, and the enhancement effect is more obvious under laminar conditions. This provides a theoretical basis for the optimization of sound wave parameters in engineering applications.
In this study, a two-dimensional cylindrical tube array model was established using the finite element method. The effects of sound wave frequency (50–200 Hz) and sound pressure level (118–140 dB) on the flow characteristics in the inter-tube gap under laminar ( Re = 150) and turbulent ( Re = 500) conditions were systematically investigated. The results show that under laminar conditions, the average gap flow velocity increases from 0.025 m/s to 0.048 m/s when the sound pressure level rises from 118 dB to 130 dB at a 50 Hz sound wave, representing a 177 % increase. However, at a constant sound pressure level of 130 dB, the flow velocity of the front row tubes (C1-C7) significantly decreases as the frequency increases from 50 Hz to 200 Hz. Under turbulent conditions, the flow velocity increases linearly by 33 % within the range of 130–140 dB at 50 Hz sound waves. Even though the flow velocity decreases when the frequency increases to 140 dB sound pressure, it is still higher than that without sound waves. The study found that low-frequency sound waves have a more significant effect on enhancing the flow of the front row tubes, while high-frequency sound waves need to consider energy dissipation. Overall, low-frequency and high sound pressure level sound waves can effectively increase the inter-tube flow velocity, and the enhancement effect is more obvious under laminar conditions. This provides a theoretical basis for the optimization of sound wave parameters in engineering applications.
作者机构：
[Binbin Chen; Hong Tian; Zhen Zhou; Yanni Xuan; Siying Liu] School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, China;[Zhijie Wang] Hunan Province Key Laboratory of Efficient and Clean Power Generation Technologies, Changsha 410007, China
通讯机构：
[Hong Tian; Yanni Xuan] S;School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, China
摘要：
A combined pretreatment of straw was carried out using acid washing and torrefaction methods. Metal-modified HZSM-5 core–shell molecular sieves were prepared by loading Zn (2, 4, and 6 wt%) and Ni (6, 8, and 10 wt%) on HZSM-5 molecular sieves and introducing MCM-41 core–shell structure. PY-GC/MS and a tubular furnace were employed to study the effects of pretreatment conditions and catalysts on the product composition distribution during wheat straw catalytic pyrolysis. XRD, SEM, BET, TPD and ICP were used to characterize the catalyst performance. It was found that the combined acid washing and torrefaction pretreatment reduced the oxygenated compounds in the bio-oil from straw catalytic pyrolysis and increased the bio-oil yield to 29.37 %. The incorporation of modified catalysts promoted the deoxygenation, zwitterionization and aromatization reactions during the straw-catalyzed pyrolysis. The monometallic loading of 4%Zn/HZ and 8%Ni/HZ catalyzed acid washing and torrefaction straw pyrolysis resulted in 54.2 % and 57.06 % yields of MAHs and 42.86 % and 38.58 % yields of BTX in bio-oil, respectively.Compared with the monometallic loading, 4%Zn8%Ni/HZ further optimized the bio-oil compositional distribution, with a MAHs yield of 64.76 %, a BTX yield of 54.69 %, and a deoxygenation performance of 81.34%.MCM-41-coated HZSM-5 produces a large mesoporous structure with channels with sufficient transport capacity, accelerating the cleavage of various types of oxygen-containing compounds in the bio-oil into smaller molecules for better conversion into aromatics. The 4%Zn8%Ni/H@M catalyst achieved a MAHs yield of 72.68 % and BTX yield of 63.43 % in the bio-oil during pyrolysis of acid-washed and torrefied wheat straw, with oxygen removal efficiency reaching 85.37 %. Therefore, the combination of feedstock pretreatment and metal-modified core–shell HZSM-5 molecular sieve could synergistically optimize both compositional distribution and production yield of bio-oil derived from biomass pyrolysis.
A combined pretreatment of straw was carried out using acid washing and torrefaction methods. Metal-modified HZSM-5 core–shell molecular sieves were prepared by loading Zn (2, 4, and 6 wt%) and Ni (6, 8, and 10 wt%) on HZSM-5 molecular sieves and introducing MCM-41 core–shell structure. PY-GC/MS and a tubular furnace were employed to study the effects of pretreatment conditions and catalysts on the product composition distribution during wheat straw catalytic pyrolysis. XRD, SEM, BET, TPD and ICP were used to characterize the catalyst performance. It was found that the combined acid washing and torrefaction pretreatment reduced the oxygenated compounds in the bio-oil from straw catalytic pyrolysis and increased the bio-oil yield to 29.37 %. The incorporation of modified catalysts promoted the deoxygenation, zwitterionization and aromatization reactions during the straw-catalyzed pyrolysis. The monometallic loading of 4%Zn/HZ and 8%Ni/HZ catalyzed acid washing and torrefaction straw pyrolysis resulted in 54.2 % and 57.06 % yields of MAHs and 42.86 % and 38.58 % yields of BTX in bio-oil, respectively.Compared with the monometallic loading, 4%Zn8%Ni/HZ further optimized the bio-oil compositional distribution, with a MAHs yield of 64.76 %, a BTX yield of 54.69 %, and a deoxygenation performance of 81.34%.MCM-41-coated HZSM-5 produces a large mesoporous structure with channels with sufficient transport capacity, accelerating the cleavage of various types of oxygen-containing compounds in the bio-oil into smaller molecules for better conversion into aromatics. The 4%Zn8%Ni/H@M catalyst achieved a MAHs yield of 72.68 % and BTX yield of 63.43 % in the bio-oil during pyrolysis of acid-washed and torrefied wheat straw, with oxygen removal efficiency reaching 85.37 %. Therefore, the combination of feedstock pretreatment and metal-modified core–shell HZSM-5 molecular sieve could synergistically optimize both compositional distribution and production yield of bio-oil derived from biomass pyrolysis.
作者机构：
[Li, Xinzhuo; Tian, Hong; Sun, Liutao; Dai, Pengfei; Xu, Chenghui; Huang, Zhangjun; Li, XZ] Changsha Univ Sci & Technol, Sch Energy & Power Engn, Changsha 410114, Peoples R China.
通讯机构：
[Li, XZ ] C;Changsha Univ Sci & Technol, Sch Energy & Power Engn, Changsha 410114, Peoples R China.
关键词：
Ammonia/methane mixture combustion;Mechanism reduction;Mechanism optimization;Artificial Neural Network;NO x emissions
摘要：
The application of ammonia/methane (NH 3 /CH 4 ) blended fuels in gas turbines has received considerable attention, and the development of their combustors requires the implementation of more precise and compact reaction mechanisms. In this work, we propose a new optimization mechanism for ammonia/methane and comprehensively verify the performance of the optimization mechanism. A detailed chemical mechanism with 65 species and 466 reactions (Detailed-Mech) was first assembled using models from the literature. A directed relation graph with error propagation (DRGEP) and computational singular perturbation (CSP) method were then used to obtain a 23-species, 73-reaction compact reaction model (Reduced-Mech). Finally, the pre-exponential factor ( A ) and activation energy ( E a ) of five significant elementary reactions were optimized using an Artificial Neural Network (ANN) to obtain the optimized mechanism (ANN-Mech). The ANN-Mech was validated at ignition delay times (IDT), laminar burning velocity (LBV), plug flow reactor (PFR) species distribution, and in the 3-D combustion chamber. The study found that the logarithmic mean errors of IDT decreased by 3.9 %. The mean error of laminar burning velocity is reduced from 18.5 % to 9.5 %, and the prediction error of NO X in ANN-Mech is reduced by 47.5 %. The results of the premixed flames simulation indicate that the temperature and velocity fields of ANN-Mech at different ammonia fractions better agree with the Detailed-Mech. Additionally, the NO error of the outlet was reduced by 30 %. The calculation speed was also increased by ten times compared to the Detailed-Mech.
The application of ammonia/methane (NH 3 /CH 4 ) blended fuels in gas turbines has received considerable attention, and the development of their combustors requires the implementation of more precise and compact reaction mechanisms. In this work, we propose a new optimization mechanism for ammonia/methane and comprehensively verify the performance of the optimization mechanism. A detailed chemical mechanism with 65 species and 466 reactions (Detailed-Mech) was first assembled using models from the literature. A directed relation graph with error propagation (DRGEP) and computational singular perturbation (CSP) method were then used to obtain a 23-species, 73-reaction compact reaction model (Reduced-Mech). Finally, the pre-exponential factor ( A ) and activation energy ( E a ) of five significant elementary reactions were optimized using an Artificial Neural Network (ANN) to obtain the optimized mechanism (ANN-Mech). The ANN-Mech was validated at ignition delay times (IDT), laminar burning velocity (LBV), plug flow reactor (PFR) species distribution, and in the 3-D combustion chamber. The study found that the logarithmic mean errors of IDT decreased by 3.9 %. The mean error of laminar burning velocity is reduced from 18.5 % to 9.5 %, and the prediction error of NO X in ANN-Mech is reduced by 47.5 %. The results of the premixed flames simulation indicate that the temperature and velocity fields of ANN-Mech at different ammonia fractions better agree with the Detailed-Mech. Additionally, the NO error of the outlet was reduced by 30 %. The calculation speed was also increased by ten times compared to the Detailed-Mech.
摘要：
The utilization of formic acid (FA) as efficient H 2 medium through the conversion between FA and CO 2 has received the great attention recently. In this research, the mesoporous material layered double hydroxide grafted with different types of amine groups (primary, secondary, and tertiary amine) have been synthesized via traditional impregnation method. The primary amine becomes the significant parameter to synthesis of ultrafine Pd nano-particles with high initial TOF of 1250 h −1 at room temperature in FA dehydrogenation. Meanwhile, the density functional theory (DFT) calculations verify that controlling the Pd sites at 2 nm can effectively accelerate the formation of hydrogen and avoid the occurrence of dehydration reaction. The subsequent hydrogenation of CO 2 into formic acid/formate on Pd-based layered double hydroxide catalyst achieves the TOF over 100 h −1 in finishing H 2 interconversion cycle. These findings will have considerable implications in the fields of H 2 generation/storage chemistry and CO 2 utilization economic.
The utilization of formic acid (FA) as efficient H 2 medium through the conversion between FA and CO 2 has received the great attention recently. In this research, the mesoporous material layered double hydroxide grafted with different types of amine groups (primary, secondary, and tertiary amine) have been synthesized via traditional impregnation method. The primary amine becomes the significant parameter to synthesis of ultrafine Pd nano-particles with high initial TOF of 1250 h −1 at room temperature in FA dehydrogenation. Meanwhile, the density functional theory (DFT) calculations verify that controlling the Pd sites at 2 nm can effectively accelerate the formation of hydrogen and avoid the occurrence of dehydration reaction. The subsequent hydrogenation of CO 2 into formic acid/formate on Pd-based layered double hydroxide catalyst achieves the TOF over 100 h −1 in finishing H 2 interconversion cycle. These findings will have considerable implications in the fields of H 2 generation/storage chemistry and CO 2 utilization economic.
摘要：
Condensation assessment of a residential building in Changsha, China-located in the hot summer and cold winter climate zone-was conducted during the Plum Rain Season (PRS) using Energy Plus simulations and field measurements. Window-opening behaviour significantly influences indoor air quality and thermal comfort. This study specifically examines how window-opening patterns, including opening duration and opening degree, affect interior surface condensation risk in a rural residential building during PRS. Results indicate that window operational status (open/closed) exerts a dominant influence on condensation risk, while varying window opening degrees during identical opening duration showed negligible differential impacts. Critical temporal patterns emerged: morning window openings during PRS should be avoided, whereas afternoon (15:00-18:00) and nighttime (18:00-06:00) ventilation proves advantageous. Optimisation analysis revealed that implementing combined afternoon and nighttime ventilation windows (15:00-18:00 + 18:00-06:00) achieved the lowest condensation risk of 0.112 among evaluated scenarios. Furthermore, monthly-adjusted window operation strategies yielded eight recommended ventilation modes, maintaining condensation risks below 0.11 and providing occupant-tailored solutions for Changsha's PRS conditions. These findings establish evidence-based guidelines for moisture control through optimised window operation in climate-responsive building management.
期刊：
Journal of Solid State Chemistry,2025年345:125205 ISSN：0022-4596
通讯作者：
Huang, Jincheng;Peng, ZY
作者机构：
[Huang, Jincheng; Zhu, Yuxiang; Zhang, Yuanfang; Peng, Zhuoyin; Zhang, Xinlong; Li, Wei; Liao, Kai; Peng, ZY; Gu, Yongjie] Changsha Univ Sci & Technol, Hunan Prov Collaborat Innovat Ctr Clean Energy & S, Sch Energy & Power Engn, Educ Dept Hunan Prov, Changsha 410111, Peoples R China.;[Zhu, Yuxiang] Wuxi Municipal Bur Ind & Informat Technol, Wuxi, Peoples R China.
通讯机构：
[Huang, JC; Peng, ZY ] C;Changsha Univ Sci & Technol, Hunan Prov Collaborat Innovat Ctr Clean Energy & S, Sch Energy & Power Engn, Educ Dept Hunan Prov, Changsha 410111, Peoples R China.
关键词：
Carbon based PbS quantum dot solar cells;Direct one-step dual ligand passivation;Charge transfer;Photovoltaic performance
摘要：
The surface traps of quantum dots are still serious problems to limit the photovoltaic performance of carbon based quantum dot solar cells. In order to optimize the surface state of quantum dot solar cells, PbI 2 /MPA dual surface ligand is introduced for direct one-step surface passivation strategy to reduce the generated undercoordinated sites and OH group in PbS quantum dot solar cells, which can provide uniform, compact and stable structure for PbS thin films. The optical absorption and charge separation properties of carbon based PbS quantum dot solar cells have been improved under this PbI 2 /MPA dual surface ligand passivation process. The excellent trap passivation has effectively improved the charge transfer efficiency of the solar cells, which exhibits higher open-circuit voltage (25.33 mA/cm 2 ), short-circuit current density (507.8 mV) and fill factor (0.525) value for carbon based PbS quantum dot solar cells. As a result, photovoltaic conversion efficiency of carbon based PbS quantum dot solar cells has been enhanced from 5.36 % to 6.75 % under this direct one-step dual PbI 2 /MPA surface ligand passivation. This work provides an effective traps passivation process to further optimize the PbS quantum dots for optoelectronic devices applications.
The surface traps of quantum dots are still serious problems to limit the photovoltaic performance of carbon based quantum dot solar cells. In order to optimize the surface state of quantum dot solar cells, PbI 2 /MPA dual surface ligand is introduced for direct one-step surface passivation strategy to reduce the generated undercoordinated sites and OH group in PbS quantum dot solar cells, which can provide uniform, compact and stable structure for PbS thin films. The optical absorption and charge separation properties of carbon based PbS quantum dot solar cells have been improved under this PbI 2 /MPA dual surface ligand passivation process. The excellent trap passivation has effectively improved the charge transfer efficiency of the solar cells, which exhibits higher open-circuit voltage (25.33 mA/cm 2 ), short-circuit current density (507.8 mV) and fill factor (0.525) value for carbon based PbS quantum dot solar cells. As a result, photovoltaic conversion efficiency of carbon based PbS quantum dot solar cells has been enhanced from 5.36 % to 6.75 % under this direct one-step dual PbI 2 /MPA surface ligand passivation. This work provides an effective traps passivation process to further optimize the PbS quantum dots for optoelectronic devices applications.
摘要：
Flue gas desulfurization characteristics of Mn-Ce metal oxides supported by ceramic-based diatomite and SBA-15 were systematically examined. The diatomite-supported sorbent (M2C2D6) achieved 96% desulfurization efficiency, which can be attributed to its robust mechanical integrity and high porosity. In contrast to the diatomite-supported sorbent, the SBA-15-supported counterpart (M2C2S6) exhibited more uniform active component dispersion, leading to a marked elevation in breakthrough sulfur capacity (T SC ) from 162 mg-SO₂/g-sorbent to 469 mg-SO₂/g-sorbent. Conversely, due to its lower porosity and diminished metal oxide affinity, heterogeneous surface distribution was observed on M2C2S6, impeding molecular interaction between SO₂ and active sites. Consequently, a reduction in desulfurization efficiency to 65% was recorded for M2C2S6. Desulfurization mechanisms were elucidated through integrated analysis of chemical reactions, external mass transfer, and internal diffusion processes. A novel Mn-Ce/diatomite-SBA carrier-blended sorbent was developed by synergistically combining the advantages of both carriers. When the diatomite: SBA-15 weight ratio reached 3:2, the hybrid sorbent (M2C2D6S4) demonstrated 96% SO₂ removal efficiency and 193 mg-SO₂/g-sorbent T SC . Notably, across five consecutive desulfurization-regeneration cycles, M2C2D6S4 consistently outperformed the single-carrier M2C2D6 in T SC , underscoring its superior durability.
Flue gas desulfurization characteristics of Mn-Ce metal oxides supported by ceramic-based diatomite and SBA-15 were systematically examined. The diatomite-supported sorbent (M2C2D6) achieved 96% desulfurization efficiency, which can be attributed to its robust mechanical integrity and high porosity. In contrast to the diatomite-supported sorbent, the SBA-15-supported counterpart (M2C2S6) exhibited more uniform active component dispersion, leading to a marked elevation in breakthrough sulfur capacity (T SC ) from 162 mg-SO₂/g-sorbent to 469 mg-SO₂/g-sorbent. Conversely, due to its lower porosity and diminished metal oxide affinity, heterogeneous surface distribution was observed on M2C2S6, impeding molecular interaction between SO₂ and active sites. Consequently, a reduction in desulfurization efficiency to 65% was recorded for M2C2S6. Desulfurization mechanisms were elucidated through integrated analysis of chemical reactions, external mass transfer, and internal diffusion processes. A novel Mn-Ce/diatomite-SBA carrier-blended sorbent was developed by synergistically combining the advantages of both carriers. When the diatomite: SBA-15 weight ratio reached 3:2, the hybrid sorbent (M2C2D6S4) demonstrated 96% SO₂ removal efficiency and 193 mg-SO₂/g-sorbent T SC . Notably, across five consecutive desulfurization-regeneration cycles, M2C2D6S4 consistently outperformed the single-carrier M2C2D6 in T SC , underscoring its superior durability.
摘要：
The thermocline latent heat packed bed system has the potential to be used for >200 °C high-temperature, 100–200 °C medium-temperature, and <100 °C low-temperature thermal energy storage applications. However, the inherent shortcoming of phase change material (PCM) is its low thermal conductivity, which inevitably restricts the heat transfer between the fillers and the heat transfer fluid. This study aims to investigate the thermal performance of the packed bed thermal energy storage (PBTES) system at mass flow rates of Re = 23-68 by filling the tank with high thermal conductivity composite PCM. An encapsulated expanded graphite/stearic acid composite PCM with a cylindrical aluminum shell was designed to prevent leakage and used as filler. The thermal conductivity of the composite is 305.7 % higher than that of pure PCM, demonstrating a higher thermal storage rate for a single capsule. Results show that this composite used as filler leads to a faster heat transfer rate between heat transfer fluid and solid fillers, decreasing the charging time by approximately 23.8 %, and keeping a more stable and distinct phase change platform at 55–60 °C. Moreover, an appropriate increase in the mass flow rate can facilitate heat transfer and improve the thermal performance of PBTES. Nevertheless, the thermal storage capacity utilization is reduced accordingly. Compared to the system with pure PCM fillers, the system with composite fillers exhibits a higher charging efficiency of 86.27 %, a higher stored thermal energy of 0.448 kWh, and a higher utilization rate at the threshold temperature. Overall, the thermal conductivity of filler is one of the primary parameters to determine the thermal performance of the thermocline latent heat packed bed system.
The thermocline latent heat packed bed system has the potential to be used for >200 °C high-temperature, 100–200 °C medium-temperature, and <100 °C low-temperature thermal energy storage applications. However, the inherent shortcoming of phase change material (PCM) is its low thermal conductivity, which inevitably restricts the heat transfer between the fillers and the heat transfer fluid. This study aims to investigate the thermal performance of the packed bed thermal energy storage (PBTES) system at mass flow rates of Re = 23-68 by filling the tank with high thermal conductivity composite PCM. An encapsulated expanded graphite/stearic acid composite PCM with a cylindrical aluminum shell was designed to prevent leakage and used as filler. The thermal conductivity of the composite is 305.7 % higher than that of pure PCM, demonstrating a higher thermal storage rate for a single capsule. Results show that this composite used as filler leads to a faster heat transfer rate between heat transfer fluid and solid fillers, decreasing the charging time by approximately 23.8 %, and keeping a more stable and distinct phase change platform at 55–60 °C. Moreover, an appropriate increase in the mass flow rate can facilitate heat transfer and improve the thermal performance of PBTES. Nevertheless, the thermal storage capacity utilization is reduced accordingly. Compared to the system with pure PCM fillers, the system with composite fillers exhibits a higher charging efficiency of 86.27 %, a higher stored thermal energy of 0.448 kWh, and a higher utilization rate at the threshold temperature. Overall, the thermal conductivity of filler is one of the primary parameters to determine the thermal performance of the thermocline latent heat packed bed system.
摘要：
A new method was proposed for predicting residual stress in light alloys using truncated conical indentation. In this method, a truncated conical indenter with a cone angle of 120°, insensitive to edge-chamfer and friction effects, was used to test the residual stress of light alloys. Selecting the ratio of indentation work between stressed and unstressed specimens as an analytical parameter, a dimensionless truncated conical indentation (TCI) model related to the ratio of indentation work between stressed and unstressed, material properties, and normalized residual stress was established via dimensional analysis and numerical calculations. The TCI model could predict equi-biaxial residual stress and uniaxial residual stress, and its accuracy was verified in a wide range of light alloys with varying residual stress by numerical simulation. The stability of the TCI model is verified numerically by introducing errors in material parameters. Truncated conical indentation tests were conducted on cruciform specimens and rectangular specimens respectively made of three aluminum alloys. The results exhibited the residual stress predicted by proposed method agrees well with the applied stress, and the relative errors between them were within ±10 % in most cases.
A new method was proposed for predicting residual stress in light alloys using truncated conical indentation. In this method, a truncated conical indenter with a cone angle of 120°, insensitive to edge-chamfer and friction effects, was used to test the residual stress of light alloys. Selecting the ratio of indentation work between stressed and unstressed specimens as an analytical parameter, a dimensionless truncated conical indentation (TCI) model related to the ratio of indentation work between stressed and unstressed, material properties, and normalized residual stress was established via dimensional analysis and numerical calculations. The TCI model could predict equi-biaxial residual stress and uniaxial residual stress, and its accuracy was verified in a wide range of light alloys with varying residual stress by numerical simulation. The stability of the TCI model is verified numerically by introducing errors in material parameters. Truncated conical indentation tests were conducted on cruciform specimens and rectangular specimens respectively made of three aluminum alloys. The results exhibited the residual stress predicted by proposed method agrees well with the applied stress, and the relative errors between them were within ±10 % in most cases.
通讯机构：
[Huang, J ] H;Hunan Acad Forestry, State Key Lab Utilizat Woody Oil Resource, Changsha 410004, Peoples R China.
关键词：
Foaming pretreatment;Neutral protease;Plastein reaction;Protein secondary structure;Sludge drying;Sludge protein
摘要：
Sludge foaming can promote sludge drying efficiency. In the foaming process, sludge protein plays a critical role due to its amphiphilic properties. However, the existing alkaline hydrolysis can generate sufficient solubilized proteins but unable to adjust their properties suitable for subsequent foaming. In response to this issue, acid pretreatment, thermal pretreatment, and enzymes of α-amylase, neutral protease (NP), and alkaline protease were applied in combination with alkaline hydrolysis. Among all methods, the enzymatic hydrolysis of 10 ‰ NP (NP10) within 2.0 h optimally adjust the proteins hydrophilic/hydrophobic, reducing foaming time by 36.7 %, drying time by 19.7 %, and energy consumption by 21.1 %. The NP pretreatment followed by alkaline hydrolysis achieved a controllable hydrolysis of proteins, with NP10 reaching the highest ratio of polypeptides to proteins at 0.4 ± 0.02, which is desirable in sludge foaming. Meanwhile, the plastein reaction was observed in NP group, characterized by increased aggregated strands and decreased α-helix/(β-sheet + random coil) in protein secondary structures, which can improve the hydrophobicity of protein hydrolysate. Two-dimensional correlation spectroscopy analysis confirmed the highest reaction activity of aggregated strands with NP. In sludge drying, the NP10 enhanced the value of effective moisture diffusivity by 51.1 % during the second falling rate period, and significantly decreased the resistance to internal moisture migration in sludge matrix. This work offered a synergistic strategy for efficient sludge foaming and drying by tuning the hydrophilic/hydrophobic balance of protein hydrolysate, and provided a deep understanding on sludge protein properties in relevant treatment processes.
Sludge foaming can promote sludge drying efficiency. In the foaming process, sludge protein plays a critical role due to its amphiphilic properties. However, the existing alkaline hydrolysis can generate sufficient solubilized proteins but unable to adjust their properties suitable for subsequent foaming. In response to this issue, acid pretreatment, thermal pretreatment, and enzymes of α-amylase, neutral protease (NP), and alkaline protease were applied in combination with alkaline hydrolysis. Among all methods, the enzymatic hydrolysis of 10 ‰ NP (NP10) within 2.0 h optimally adjust the proteins hydrophilic/hydrophobic, reducing foaming time by 36.7 %, drying time by 19.7 %, and energy consumption by 21.1 %. The NP pretreatment followed by alkaline hydrolysis achieved a controllable hydrolysis of proteins, with NP10 reaching the highest ratio of polypeptides to proteins at 0.4 ± 0.02, which is desirable in sludge foaming. Meanwhile, the plastein reaction was observed in NP group, characterized by increased aggregated strands and decreased α-helix/(β-sheet + random coil) in protein secondary structures, which can improve the hydrophobicity of protein hydrolysate. Two-dimensional correlation spectroscopy analysis confirmed the highest reaction activity of aggregated strands with NP. In sludge drying, the NP10 enhanced the value of effective moisture diffusivity by 51.1 % during the second falling rate period, and significantly decreased the resistance to internal moisture migration in sludge matrix. This work offered a synergistic strategy for efficient sludge foaming and drying by tuning the hydrophilic/hydrophobic balance of protein hydrolysate, and provided a deep understanding on sludge protein properties in relevant treatment processes.
摘要：
In this study, a systematic procedure was proposed, according to an interdisciplinary perspective, to apply the Fogg Behavioral Model (FBM) to the field of energy-saving behavior change. On the basis of this procedure, a standardized scale was developed to assess the motivation and ability variables associated with energy-saving behaviors among building occupants within the FBM framework. First the latent FBM variables were mapped onto the context of energy-saving behavior change. Then, an initial item pool was established by adopting human behavior-related classical theories and corresponding measurement items. Subsequently, data was collected to validate the initial item pool and conduct three studies: (1) study 1 refined unclear expressions through expert verification; (2) study 2 evaluated the item pool in a representative sample (high- and low-score groups) using a Critical-ratio test and explored the factorial structure of the item pool through exploratory factor analysis, and (3) study 3 confirmed the proposed structure using confirmatory factor analysis and examined convergent and discriminant validity. Ultimately, an 11-item version of the standardized scale was developed, which demonstrated high internal consistency and a good overall model fit. Evidence from discriminant and convergent validity analyses also confirmed its effectiveness as a comprehensive measurement tool. The proposed procedure, along with the developed standardized scale, facilitates the objective measurement of motivation and ability variables, thereby enhancing the practical application of FBM in the field of energy-saving behavioral change. Furthermore, researchers in other domains can adapt these variables to extend FBM’s applicability in driving behavioral change across diverse contexts.
In this study, a systematic procedure was proposed, according to an interdisciplinary perspective, to apply the Fogg Behavioral Model (FBM) to the field of energy-saving behavior change. On the basis of this procedure, a standardized scale was developed to assess the motivation and ability variables associated with energy-saving behaviors among building occupants within the FBM framework. First the latent FBM variables were mapped onto the context of energy-saving behavior change. Then, an initial item pool was established by adopting human behavior-related classical theories and corresponding measurement items. Subsequently, data was collected to validate the initial item pool and conduct three studies: (1) study 1 refined unclear expressions through expert verification; (2) study 2 evaluated the item pool in a representative sample (high- and low-score groups) using a Critical-ratio test and explored the factorial structure of the item pool through exploratory factor analysis, and (3) study 3 confirmed the proposed structure using confirmatory factor analysis and examined convergent and discriminant validity. Ultimately, an 11-item version of the standardized scale was developed, which demonstrated high internal consistency and a good overall model fit. Evidence from discriminant and convergent validity analyses also confirmed its effectiveness as a comprehensive measurement tool. The proposed procedure, along with the developed standardized scale, facilitates the objective measurement of motivation and ability variables, thereby enhancing the practical application of FBM in the field of energy-saving behavioral change. Furthermore, researchers in other domains can adapt these variables to extend FBM’s applicability in driving behavioral change across diverse contexts.
通讯机构：
[Jiang, FL; Zhang, H ] H;[Li, W ] C;Changsha Univ Sci & Technol, Coll Energy & Power Engn, Changsha 410114, Peoples R China.;Hunan Univ, Coll Mat Sci & Engn, Changsha 410082, Peoples R China.
关键词：
Al-Cu-Mg alloys;Multi-stage hot deformation;Warm deformation;Dynamic softening and hardening;Static softening and hardening;Pre-precipitation microstructure
摘要：
Complex dynamic and static softening behaviors in flow stress evolutions serve as important indicator for optimizing the power or load required by thermomechanical processes of Al-Cu-Mg alloys. However, the flow stress behaviors during the commonly employed industrial multi-stage warm and hot forming of Al-Cu-Mg alloys are rarely reported. In this work, therefore, the complicated flow hardening or softening mechanisms during multi-stage warm (200 ºC) and hot (300 ºC and 400 ºC) deformation of the air-cooled (AC) and water-quenched (WQ) Al-Cu-Mg-Zr alloy after solution treatment were studied by means of isothermal (1, 2, 3, 6 passes) compression tests, microstructural characterization and in-situ electrical resistivity monitoring. During warm deformation at 200 ºC, clear flow hardening was presented until high strain level (0.8–1.0) for AC and WQ alloy, after which slight flow softening and hardening was observed due to the dynamic recovery caused by high strain energy, respectively. But the more the number of deformation pass, the stronger static hardening caused by static precipitation, leading to higher flow stress and enhancing the flow softening behaviors within high strain range (0.8–1.2). During hot deformation at 300 ºC and 400 ºC, the clear dynamic and static softening of AC and WQ alloy are mainly attributed to dynamic/static recovery (DRV and SRV) and precipitation, respectively. However, the strain energy consumed by static recovery and/or precipitation would increase significantly with rising number of static holding process. Consequently, the stored strain energy for the occurrence of DRV during later stage of deformation ( ε >0.8) was insufficient, leading to flow hardening of 3- and 6-pass deformation.
Complex dynamic and static softening behaviors in flow stress evolutions serve as important indicator for optimizing the power or load required by thermomechanical processes of Al-Cu-Mg alloys. However, the flow stress behaviors during the commonly employed industrial multi-stage warm and hot forming of Al-Cu-Mg alloys are rarely reported. In this work, therefore, the complicated flow hardening or softening mechanisms during multi-stage warm (200 ºC) and hot (300 ºC and 400 ºC) deformation of the air-cooled (AC) and water-quenched (WQ) Al-Cu-Mg-Zr alloy after solution treatment were studied by means of isothermal (1, 2, 3, 6 passes) compression tests, microstructural characterization and in-situ electrical resistivity monitoring. During warm deformation at 200 ºC, clear flow hardening was presented until high strain level (0.8–1.0) for AC and WQ alloy, after which slight flow softening and hardening was observed due to the dynamic recovery caused by high strain energy, respectively. But the more the number of deformation pass, the stronger static hardening caused by static precipitation, leading to higher flow stress and enhancing the flow softening behaviors within high strain range (0.8–1.2). During hot deformation at 300 ºC and 400 ºC, the clear dynamic and static softening of AC and WQ alloy are mainly attributed to dynamic/static recovery (DRV and SRV) and precipitation, respectively. However, the strain energy consumed by static recovery and/or precipitation would increase significantly with rising number of static holding process. Consequently, the stored strain energy for the occurrence of DRV during later stage of deformation ( ε >0.8) was insufficient, leading to flow hardening of 3- and 6-pass deformation.
期刊：
Journal of Energy Storage,2025年134:118080 ISSN：2352-152X
通讯作者：
Meng Wang
作者机构：
[Sihui Li; Yonghuan Li; Meng Wang; Li Xie; Guowei Bo] College of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, PR China;[Chujie Lu] Faculty of Architecture and the Built Environment, Delft University of Technology, the Netherlands
通讯机构：
[Meng Wang] C;College of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, PR China
摘要：
Proper co-optimization of photovoltaic driven air conditioning (PVAC) systems with load flexibility and batteries is pivotal for achieving zero energy buildings (ZEBs). However, practical implementation faces challenges from separate optimization with conflicting objectives, neglect of spatial-temporal occupancy features, and limited consideration of energy, economic, and environmental performance. This study proposes a hierarchical multi-objective co-optimization framework for capacity design and control strategy of the PVAC coupling systems, with the two optimization layers sharing the same multi-objective function. The optimization method balances energy, economic, environmental performance by key metrics including thermal comfort satisfaction ratio (TCSR), grid cumulative action power (GP total ), net present value (NPV) and emission reduction (ER). The optimal capacity optimization of PV and batteries for PVAC systems was solved by the NSGA-II and TOPSIS algorithms. Based on the case study of a multi-functional academic building, the optimization results of the off-grid system and the grid-connected system were calculated under different configuration of PV and battery capacity, and the relationship between the indicators was discussed. The optimization method of off-grid PVAC systems achieves 24 % reduction in PV capacity while maintaining 85.85 % TCSR, 123,800 CNY of NPV, and 167.26 tons of ER. Grid-connected systems with 165.88 kW PV capacity and 71.26 kWh battery capacity can achieve 100 % of TCSR, 1861.8 kW of GP total , 148,300 CNY of NPV, and 174.70 tons of ER. The study provides an innovative and practical method for capacity design and energy control of PVAC coupling systems to achieve zero energy buildings.
Proper co-optimization of photovoltaic driven air conditioning (PVAC) systems with load flexibility and batteries is pivotal for achieving zero energy buildings (ZEBs). However, practical implementation faces challenges from separate optimization with conflicting objectives, neglect of spatial-temporal occupancy features, and limited consideration of energy, economic, and environmental performance. This study proposes a hierarchical multi-objective co-optimization framework for capacity design and control strategy of the PVAC coupling systems, with the two optimization layers sharing the same multi-objective function. The optimization method balances energy, economic, environmental performance by key metrics including thermal comfort satisfaction ratio (TCSR), grid cumulative action power (GP total ), net present value (NPV) and emission reduction (ER). The optimal capacity optimization of PV and batteries for PVAC systems was solved by the NSGA-II and TOPSIS algorithms. Based on the case study of a multi-functional academic building, the optimization results of the off-grid system and the grid-connected system were calculated under different configuration of PV and battery capacity, and the relationship between the indicators was discussed. The optimization method of off-grid PVAC systems achieves 24 % reduction in PV capacity while maintaining 85.85 % TCSR, 123,800 CNY of NPV, and 167.26 tons of ER. Grid-connected systems with 165.88 kW PV capacity and 71.26 kWh battery capacity can achieve 100 % of TCSR, 1861.8 kW of GP total , 148,300 CNY of NPV, and 174.70 tons of ER. The study provides an innovative and practical method for capacity design and energy control of PVAC coupling systems to achieve zero energy buildings.
摘要：
SiO2 soot preform sintering is a critical step in the indirect chemical vapor deposition (CVD) method for synthesizing high-quality silica glass, which involves hydroxyl (OH) decomposition, heat and mass transfer, as well as densification. These phenomena are not fully coupled in the traditional models, which leads to inaccurate numerical predictions. To address this, a porous media model with multiphase transport and solid mechanics bidirectional coupling (MTM) is proposed for the soot preform sintering process in this paper. The model is validated by experimental results. Using this model, the densification behavior of soot preform during sintering process is predicted, and the effects of densification on heat and mass transfer are thoroughly examined. The OH decomposition rate and gas phase transport are intensified in the later sintering stage when densification occurs significantly. Consequently, the OH is concentrated, presenting a ringed-shape distribution. The temperature distribution is also affected, which transforms from a layered shape to a ringed shape, with the maximum temperature decreasing by approximately 20 °C. Furthermore, the effects of the temperature rise curve are explored. It is found that a higher preheating temperature and a longer holding time are preferable for the synthesis of high-quality silica glass.
SiO2 soot preform sintering is a critical step in the indirect chemical vapor deposition (CVD) method for synthesizing high-quality silica glass, which involves hydroxyl (OH) decomposition, heat and mass transfer, as well as densification. These phenomena are not fully coupled in the traditional models, which leads to inaccurate numerical predictions. To address this, a porous media model with multiphase transport and solid mechanics bidirectional coupling (MTM) is proposed for the soot preform sintering process in this paper. The model is validated by experimental results. Using this model, the densification behavior of soot preform during sintering process is predicted, and the effects of densification on heat and mass transfer are thoroughly examined. The OH decomposition rate and gas phase transport are intensified in the later sintering stage when densification occurs significantly. Consequently, the OH is concentrated, presenting a ringed-shape distribution. The temperature distribution is also affected, which transforms from a layered shape to a ringed shape, with the maximum temperature decreasing by approximately 20 °C. Furthermore, the effects of the temperature rise curve are explored. It is found that a higher preheating temperature and a longer holding time are preferable for the synthesis of high-quality silica glass.
期刊：
Journal of Alloys and Compounds,2025年1021:179708 ISSN：0925-8388
通讯作者：
Chen, W;Lin, YC
作者机构：
[Chen, Wei; Gan, Lang; Chen, Kang; Xu, Xinru; Li, Cong; Chen, W; Qiu, Wei; Chen, Jian] Changsha Univ Sci & Technol, Sch Energy & Power Engn, Changsha 410114, Hunan, Peoples R China.;[Jiang, Peipei] Univ South China, Sch Resources Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Lin, Yongcheng; He, Daoguang] Cent South Univ, Sch Mech & Elect Engn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Chen, W ; Lin, YC ] C;Changsha Univ Sci & Technol, Sch Energy & Power Engn, Changsha 410114, Hunan, Peoples R China.;Cent South Univ, Sch Mech & Elect Engn, Changsha 410083, Hunan, Peoples R China.
关键词：
Al-Si-Mg alloy;Rare earth oxide;Mechanical properties;Corrosion resistance;Al 7 Fe 6 La phase
摘要：
This study examines the impact of the rare earth oxide La 2 O 3 on the microstructure, mechanical and corrosion resistance properties of as-cast Al-Si-Mg (A356) alloys, with a specific focus on the A356 alloy. By incorporating varying amounts of La 2 O 3 (0 wt%, 0.2 wt%, 0.3 wt%, and 0.4 wt%) into the A356 alloy, four samples (AL0, AL2, AL3, and AL4) were produced. The findings demonstrate that an optimal addition of La 2 O 3 (0.3 wt%) can effectively reduce the secondary dendrite arm spacing (SDAS), refine the eutectic Si phase, and modify the morphology of Fe-rich phases, thereby significantly enhancing the overall performance of the alloy. The transformation in the morphology of the Fe-rich phases is accompanied by changes in their elemental composition, including the transition from elongated rod-like AlFeSi phases to shorter rod-like Al 7 Fe 6 La phases. Specifically, the AL3 sample displays the best mechanical properties, with increases in hardness, yield strength (YS), ultimate tensile strength (UTS) and elongation (EL) of 11.11 %, 71.43 %, 36.45 % and 233.46 %, respectively. Moreover, AL3 exhibits superior corrosion resistance, characterized by the highest corrosion potential (-0.88 V) and the lowest corrosion current density (3.6 ×10 −7 A/cm 2 ). The addition of La 2 O 3 promotes grain refinement, reduces the size of secondary phase particles, and the formation of Al 7 Fe 6 La phase collectively contributing to the enhanced performance of the A356 alloy. The present study provides theoretical support for utilizing rare earth oxides as a viable alternative to pure rare earth metals in Al alloys, presenting a cost-efficient strategy tailored for industrial implementations.
This study examines the impact of the rare earth oxide La 2 O 3 on the microstructure, mechanical and corrosion resistance properties of as-cast Al-Si-Mg (A356) alloys, with a specific focus on the A356 alloy. By incorporating varying amounts of La 2 O 3 (0 wt%, 0.2 wt%, 0.3 wt%, and 0.4 wt%) into the A356 alloy, four samples (AL0, AL2, AL3, and AL4) were produced. The findings demonstrate that an optimal addition of La 2 O 3 (0.3 wt%) can effectively reduce the secondary dendrite arm spacing (SDAS), refine the eutectic Si phase, and modify the morphology of Fe-rich phases, thereby significantly enhancing the overall performance of the alloy. The transformation in the morphology of the Fe-rich phases is accompanied by changes in their elemental composition, including the transition from elongated rod-like AlFeSi phases to shorter rod-like Al 7 Fe 6 La phases. Specifically, the AL3 sample displays the best mechanical properties, with increases in hardness, yield strength (YS), ultimate tensile strength (UTS) and elongation (EL) of 11.11 %, 71.43 %, 36.45 % and 233.46 %, respectively. Moreover, AL3 exhibits superior corrosion resistance, characterized by the highest corrosion potential (-0.88 V) and the lowest corrosion current density (3.6 ×10 −7 A/cm 2 ). The addition of La 2 O 3 promotes grain refinement, reduces the size of secondary phase particles, and the formation of Al 7 Fe 6 La phase collectively contributing to the enhanced performance of the A356 alloy. The present study provides theoretical support for utilizing rare earth oxides as a viable alternative to pure rare earth metals in Al alloys, presenting a cost-efficient strategy tailored for industrial implementations.
期刊：
Chemical Engineering Journal,2025年511:162058 ISSN：1385-8947
通讯作者：
Zou, Liangyu;Jia, CK;Liang, ZW
作者机构：
[Zou, Liangyu; Jia, CK; Jia, Chuankun; Huang, Yunkun; Xiao, Junbing] Changsha Univ Sci & Technol, Sch Energy & Power Engn, Dept Energy Storage Sci & Engn, Changsha 410114, Hunan, Peoples R China.;[Huang, Yangqiang; Liang, Zhiwu] Hunan Univ, Coll Chem & Chem Engn, Joint Int Ctr CO2 Capture & Storage iCCS, Prov Hunan Key Lab Cost Effect Utilizat Fossil Fue, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Zou, LY; Jia, CK ] C;[Liang, ZW ] H;Changsha Univ Sci & Technol, Sch Energy & Power Engn, Dept Energy Storage Sci & Engn, Changsha 410114, Hunan, Peoples R China.;Hunan Univ, Coll Chem & Chem Engn, Joint Int Ctr CO2 Capture & Storage iCCS, Prov Hunan Key Lab Cost Effect Utilizat Fossil Fue, Changsha 410082, Hunan, Peoples R China.
关键词：
Di-n-butylamine;Fomic acid dehydrogenation;Absorption/desorption rate;CO2 capture;Cyclic CO2 capacity
摘要：
Background Secondary amines with strong alkalinity can be used as additives in the field of formic acid hydrogen production. The novel absorbent system combing secondary amine and tertiary amine is prosperous in industrial application of CO 2 capture.
Secondary amines with strong alkalinity can be used as additives in the field of formic acid hydrogen production. The novel absorbent system combing secondary amine and tertiary amine is prosperous in industrial application of CO 2 capture.
Results As an additive of formic acid dehydrogenation system with Pd/C catalyst, the promoting effect of di-n-butylamine (DBA) can be achieved over 40% ahead of the peer additives. Screening test of hybrid solutions composed of additive amine, DBA, and H 2 O were comprehensively investigated using the rapid solvent screening apparatus and VLE apparatus. The combination of DBA and N,N-dimethyl ethanolamine (DMEA) achieved the higher rich loading, strong cyclic CO 2 capacity and stripping rate over a wide range of CO 2 loading. Also, the absorption of high content CO 2 into the hybrid DBA/DMEA solution was investigated in a lab-scale simulated absorption device. The effects of operating parameters (CO 2 loading, solvent concentration and liquid temperature (T), etc.) on the CO 2 absorption were evaluated in terms of CO 2 removal rate ( θ CO2 ). Furthermore, a predicted model of θ CO2 , which could be suitable for different solution systems with generated gas treatment of FA dehydrogenation, was also proposed and developed using semi-empirical models as function of operating parameters in this work.
As an additive of formic acid dehydrogenation system with Pd/C catalyst, the promoting effect of di-n-butylamine (DBA) can be achieved over 40% ahead of the peer additives. Screening test of hybrid solutions composed of additive amine, DBA, and H 2 O were comprehensively investigated using the rapid solvent screening apparatus and VLE apparatus. The combination of DBA and N,N-dimethyl ethanolamine (DMEA) achieved the higher rich loading, strong cyclic CO 2 capacity and stripping rate over a wide range of CO 2 loading. Also, the absorption of high content CO 2 into the hybrid DBA/DMEA solution was investigated in a lab-scale simulated absorption device. The effects of operating parameters (CO 2 loading, solvent concentration and liquid temperature (T), etc.) on the CO 2 absorption were evaluated in terms of CO 2 removal rate ( θ CO2 ). Furthermore, a predicted model of θ CO2 , which could be suitable for different solution systems with generated gas treatment of FA dehydrogenation, was also proposed and developed using semi-empirical models as function of operating parameters in this work.
关键词：
bionic amphibious robot;composite drive;motion control;track mechanism;undulating fin
摘要：
Amphibious robots offer promising applications in field scenarios such as search and rescue, exploration and reconnaissance, and environment monitoring. However, achieving high locomotion performance in terrestrial, aquatic, and soft muddy transition areas remains challenging. This study presents a novel amphibious robot based on the hybrid drive of tracks and bionic fins. The robot is driven by a pair of tracks on land and by a pair of undulating fins underwater, without the need for switching operating modes due to the simultaneous drive of the two components. The structure design is introduced and the united operating strategies are derived for propulsion in multiple environments propulsion. A land-water united controller for the heading angle and track/fin frequency is designed based on a mathematical model. In field experiments, the robot achieved the maximum linear velocities of 2 m/s on land and 0.51 m/s underwater, with maximum yaw rates of 225 / degrees s ${}<^>{\circ }/{\rm{s}}$ and 100 / degrees s ${}<^>{\circ }/{\rm{s}}$, respectively. The robot could transition seamlessly between land and water in less than 2 s. The closed-loop control experiments demonstrated that the robot could quickly follow the desired angle with minimal error in both media using the same controller and parameters. The proposed simultaneous drive method enhances the multi-terrain motion capacity and cross-medium performance while reducing control complexity of amphibious robot, providing a new perspective for the development of self-adaptive and high-performance amphibious robots for practical application.
作者机构：
[Shen, Shuyi; Luo, Hang; Zhang, Dou; Wan, Yuting; He, Guanghu; Li, Xiaona; Luo, H; Peng, Jiajun] Cent South Univ, State Key Lab Powder Met, Changsha, Hunan Province, Peoples R China.;[Yan, Zhongna] Changsha Univ Sci & Technol, Sch Energy & Power Engn, Changsha, Hunan Province, Peoples R China.;[Zha, Jun-Wei] North China Elect Power Univ, Sch Elect & Elect Engn, State Key Lab Alternate Elect Power Syst Renewable, Beijing, Peoples R China.
通讯机构：
[Zhang, D ; Luo, H] C;[Zha, JW ] N;Cent South Univ, State Key Lab Powder Met, Changsha, Hunan Province, Peoples R China.;North China Elect Power Univ, Sch Elect & Elect Engn, State Key Lab Alternate Elect Power Syst Renewable, Beijing, Peoples R China.
摘要：
Polymer dielectrics with enhanced thermal stability and electrical insulation are urgently needed for capacitive energy storage applications in electric power systems. There is a persistent challenge to break the contradictory correlation between high heat resistance and low electrical conduction in polymers. Here, we employ benzyl-induced crosslinking to rearrange short-range structural units in polyimide chains, reducing electrical conduction loss. The designed polymer exhibits an electrical conductivity more than 3 orders of magnitude lower than that of commercial heat-resistant polymers, while its glass transition temperature (Tg) increases from 236.31 °C (for polyetherimide) to 289.72 °C. Consequently, a discharged energy densities of 6.38 J cm−3 and 3.04 J cm−3, with charge-discharge efficiencies above 90%, are achieved at 200 °C and 250 °C, respectively, demonstrating among the best in all-organic dielectric polymers. This work presents a feasible approach to break the adverse correlation between thermal stability and electrical insulation in polyimide materials. Polymer dielectrics have potential in capacitive energy storage applications, but achieving the required thermal stability and electrical insultation is challenging. Here, the authors report a method to rearrange short-range structural units within polyimide chains to give improved properties.
