In this study,the pyrolysis and combustion characteristics of sugar tar waste liquid(STWL)affected by different water contents and oxygen concentrations are studied by using a Thermogravimetric analysis,and the kineti...In this study,the pyrolysis and combustion characteristics of sugar tar waste liquid(STWL)affected by different water contents and oxygen concentrations are studied by using a Thermogravimetric analysis,and the kinetic parameters of the pyrolysis and combustion are obtained by the Coats-Redfern integral method.The results show that both the pyrolysis process and the combustion process of the STWLs are divided into two stages under the different water contents and oxygen concentrations.The low and high temperature ranges for pyrolysis and combustion process are below 420℃ and 420-500℃ and below 400℃ and 400500℃,respectively.As the water contents increase,the pyrolysis initial temperature Ti,p gradually decreases and the comprehensive pyrolysis characteristic index D also decreases for the pyrolysis process.The Ti,p increases from 224℃to 350℃,and the index D decreases from 3.30×10-4to 0.811×10-4% 3·min-2·℃-3.The combustion ignition temperature Ti,c increases and the comprehensive combustion characteristic index S decreases.When the oxygen concentration increases,the ignition temperature and the burnout temperature remain almost constant,with variations of 3.6%and 2.0%,respectively.Besides,the pyrolysis and combustion process of the STWL obeys the stochastic nucleation and subsequent growth model,i.e.,[-ln(1-α)]4.These results are expected to provide some valuable guidance for organic waste liquid incineration treatment.展开更多
In-situ combustion(ISC)has a huge potential in recovering heavy oil resources with a low environmental footprint.At the end of the ISC operation,a huge amount of thermal energy is left in the reservoir.By appropriatel...In-situ combustion(ISC)has a huge potential in recovering heavy oil resources with a low environmental footprint.At the end of the ISC operation,a huge amount of thermal energy is left in the reservoir.By appropriately recovering the thermal energy in the depleted reservoirs after ISC operation,it could extend the economic life of the heavy oil reservoirs.This work investigated the potential of extracting heat using the cold water and CO2as the working fluids to advance the knowledge base regarding the thermal energy recovery and CO2storage in depleted ISC reservoirs.The extracted fluids are fed to the surface binary cycle for power generation or district heating.Simulation of ISC was performed to estimate the temperature,energy,and fluids distributions after 20 years of the oil production.An assessment of the energy remaining in the reservoir is performed.It is estimated that a total of 3×1014 J thermal energy was left underground after ISC operation in the typical five-spot well pattern.Subsequently,an examination of the potentially recoverable energy from the post ISC operation is performed.Cold water and CO2are recirculated into the reservoir for energy recovery.The results indicates that the heavy oil reservoir after ISC operation can be regarded as an artificial geothermal system for subsurface thermal energy extraction.As the water circulation rate increases from 200 m3/day and to 400 m3/day and 600 m3/day,the average reservoir temperature is declined to 95℃,79℃,and 71℃,respectively.Meanwhile,the corresponding thermal energy recovery factors are 48%,63%,and 77%,respectively.Larger water circulation rate can generate high energy output and high energy recovery in the post ISC operation.The thermal energy recovery could prolong the energy production to 15 to 20 years in a depleted reservoir.Except for thermal energy extraction,a total of 6100 tons of CO2can be sequestrated underground by using the CO2as the working fluids in the five spot well pattern.The numerical investigation in this study indicate that huge energy extraction potential and CO2storage can be achieved at the full field scale.Utilization of subsurface thermal energy after the ISC operation is a beneficial choice to offset the operating costs,reduce the CO2emission and extend the economic life of reservoir.展开更多
Single-atom catalysts possess the ability to effectively modulate the chemical environment of active sites,thereby synergistically enhancing catalytic reaction activity due to their unique electronic properties.In thi...Single-atom catalysts possess the ability to effectively modulate the chemical environment of active sites,thereby synergistically enhancing catalytic reaction activity due to their unique electronic properties.In this study,single-atom Ni-doped CeO2-supported Pd catalysts were designed and synthesized.The introduction of single-atom Ni induced lattice distortion in the CeO2 support,resulting in an increased concentration of oxygen vacancies on the surface.This increase in oxygen vacancies enhances the strong metal-support interactions between Pd and the support.Under the intensified metal-support interaction effect,Pd species tend to transfer more electrons to Ni atoms and adjacent O atoms,leading to a higher proportion of high oxidation states(Pd4+)in PdOx species.The presence of high-valent Pd4+and oxygen vacancies synergically enhances the activation of C-H bonds in methane and the adsorption and dissociation of oxygen,significantly improving the overall catalytic activity of methane combustion.This study provides a critical theoretical foundation and practical guidance for the design and optimization of clean energy catalysts.展开更多
The inherent irreducibility and limited sulfur dioxide tolerance of zeolites constrain oxygen exchange efficiency in palladium/zeolite catalysts,which can adversely affect their performance in methane combustion.Herei...The inherent irreducibility and limited sulfur dioxide tolerance of zeolites constrain oxygen exchange efficiency in palladium/zeolite catalysts,which can adversely affect their performance in methane combustion.Herein,a novel molecular sieve(Silicate-1,denoted as S-1)catalyst functionalized with rare earth oxide sites was developed for catalytic methane combustion.Although both Pd/S-1@CeO2-30(in which CeO2content was 30 wt.%)and Pd/S-1 catalysts demonstrated comparable initial catalytic activities,the Pd/S-1@CeO2-30 sample achieved a methane reaction rate of 114.0μmol/(gPd·s)and the highest TOFPd(0.033s-1),with a 90%methane conversion at 424℃ at a space velocity of 20,000 mL/(g h).The CeO2shell in Pd/S-1@CeO2-30 exhibited the superior longterm stability that was attributed to the redox property of CeO2,which could facilitate the provision of abundant oxygen species.As a result,the Pd/S-1@CeO2-30 catalyst maintained stable performance in 10,000-ppm CH4methane combustion at 400℃ and retained a high CH4conversion efficiency even under exposure to 50 ppm SO2.Similarly,Ce0.6Zr0.4O2or Sm2O3shell also demonstrated comparable SO2resistance.Detailed characterization results revealed that CeO2acted as an exceptional redox center,significantly enhanced SO2adsorption,and effectively inhibited the poisoning of the active PdO sites by SO2,leading to a notable improvement in sulfur dioxide tolerance.These findings highlighted the critical role of the core-shell structure in enhancing catalyst resistance to SO2poisoning during methane combustion.The present work provides valuable insights into the appropriate designing of advanced core-shell catalysts with improved durability and performance in the sulfur dioxide-containing environments.展开更多
Engineering the pore structure of biomass-derived activated carbons is critical for optimizing their performance in adsorptionbased applications.This study demonstrates for the first time that washing hydrochars in so...Engineering the pore structure of biomass-derived activated carbons is critical for optimizing their performance in adsorptionbased applications.This study demonstrates for the first time that washing hydrochars in solvents of different polarity before activation is a simple yet powerful strategy to tailor pore size distribution.Hydrochar is produced from spent coffee grounds via hydrothermal carbonization,followed by washing in various solvents and activation in KOH.This results in carbons with a very large surface area(~2700 m2/g),and washing is demonstrated to significantly increase product yield.Furthermore,washing in non-polar or mixed-polarity solvents removes long-chain carboxylic acids and esters from the hydrochar,promoting the development of narrow micropores while suppressing mesopore formation.To illustrate the impact of this structural control of porous carbons,post-combustion CO2capture is investigated as a case study.Narrower pore size distribution enhances CO2uptake,significantly improving capacity from 2.8 mmol/g for unwashed samples to 3.8 mmol/g for acetone-washed samples.Interestingly,moderate pore size(9-12Å)is shown to be optimal for CO2:N2 selectivity,while smaller pores result in lower selectivity due to stronger interactions between N2 and the pore walls.These findings highlight the potential role of solvent washing in directing pore architecture of hydrochars for adsorption-based carbon capture technologies and beyond.展开更多
Engineering the morphology of the support is effective in tuning the redox properties of active metals for efficient catalytic methane combustion via tailoring the metal-support interaction.Herein,uniform Ir nanoparti...Engineering the morphology of the support is effective in tuning the redox properties of active metals for efficient catalytic methane combustion via tailoring the metal-support interaction.Herein,uniform Ir nanoparticles supported on anatase TiO2with different morphologies predominantly exposing{100},{101},and{001}planes were synthesized and tested for methane combustion.The CH4 catalytic activity shows a remarkable TiO2-facet-dependent effect and follows the order of Ir/TiO2-{100}>Ir/TiO2-{101}>>Ir/TiO2-{001}.Detailed characterizations and DFT calculations reveal that compared with Ir-TiO2-{101}and Ir-TiO2-{001}interfaces,the superior Ir-TiO2-{100}interface facilitates the generation of electron-rich Ir species through more profound charge transfer from TiO2-{100}to Ir atoms.The electron-rich Ir structure,featuring abundant defect oxygen vacancies,significantly enhances the redox properties of active Ir species and reduces the activation energy for breaking the initial C-H bond in CH4,resulting in the superior catalytic activity for methane combustion.These findings deepen fundamental insights into the TiO2-facet-dependent reactivity of different Ir/TiO2nanomaterials in methane oxidation and pave the way for designing efficient Ir-based methane oxidation catalysts.展开更多
为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P2O5∶K2O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260...为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P2O5∶K2O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260全秸秆茬地洁区旋耕智能施肥播种机和3ZF-4(200)中耕追肥机,设置7种施肥模式(30 cm+15 cm宽窄行种植):以尿素4次分施(N 240 kg hm-2,基肥∶分蘖肥∶拔节肥∶孕穗肥=5∶1∶2∶2,窄行基施,追肥全田撒施)为对照(CK);减氮15%(N 204 kg hm-2)条件下设置6种处理:M1(100%SRF窄行基施);M2(60%SRF窄行基施+40%U拔节期窄行撒施);M3(60%SRF窄行基施+40%U返青期宽行条施);M4(60%SRF窄行基施+40%SRF返青期窄行撒施);M5(60%SRF窄行基施+40%SRF返青期宽行条施);M4+5(60%SRF窄行基施+20%SRF返青期宽行条施+20%SRF返青期窄行撒施)。研究比较不同施肥模式对小麦产量效益、根系形态生理、氮素利用效率及N2O排放的影响。结果表明,与CK相比,M2~M5处理提高了小麦产量(4.0%~19.0%)和经济效益(13.7%~35.7%),其中M4和M5处理表现最优,分别增产14.1%和19.0%,经济效益提升34.5%和35.7%。这些处理明显改善了根系特性(根干重密度增加9.7%~111.8%,根系活力和氧化力分别提高6.8%~52.0%和4.2%~44.2%),降低N2O累积排放量22.6%~34.5%,提高0~20 cm土层硝态氮含量11.2%~40.0%。在氮素利用方面,M2~M5处理均提高了籽粒氮素积累量、花后氮素积累量及其对籽粒氮素的贡献率,氮肥利用效率指标(包括偏生产力、农学效率和表观利用率)分别显著提升了22.4%~40.0%、29.7%~74.3%和9.41~18.77个百分点。值得注意的是,M4和M5处理表现出最优的综合效益:N2O累积排放量降幅最大(分别达27.0%和34.5%),氮肥表观利用率2季均维持在43.0%以上(均值分别为43.5%和46.8%),同时在生育后期保持较高的根系活性和耕层无机氮含量。相比之下,M1处理虽然实现了最大的N2O减排效果(降幅35.9%),但导致减产10.4%和经济效益下降10.8%,且氮肥利用效率呈现不稳定的年际变化特征。而优化处理M4+5进一步改善了根系形态生理特性,并提高氮肥表观利用率和籽粒氮素积累量。综上,减氮15%条件下(N 204 kg hm-2),缓混肥2次施用处理(M4和M5)能实现产量、经济效益、氮肥利用效率和N2O减排的协同提高,并以追肥深施处理(M5)效应更强。本研究为稻茬小麦缓释肥减氮优化高效应用提供重要理论依据。展开更多
Photo-assisted Mg/seawater batteries(PAMSBs)are attractive power source for marine equipment due to the advan tage of simultaneous generation of electricity an d hydrogen from seawater.Nonetheless,the serious photocor...Photo-assisted Mg/seawater batteries(PAMSBs)are attractive power source for marine equipment due to the advan tage of simultaneous generation of electricity an d hydrogen from seawater.Nonetheless,the serious photocorrosion of photocathodes results in dissatisfactory battery performan ce,which substantially hinder their practical applications.Herein,we design a CuO/Cu2O heterostructure as the photocathode of PAMSBs via a facile in-situ electrochemical strategy,successfully enhance the photo-stability of bare Cu2O.During half-cell photoelectrochemical water splitting,the newly-developed CuO/Cu2O photocathode reveals a photo-current density about 2.2 mA cm-2at 0 V(vs.RHE)and enables nearly 100% retention of the initial photocurrent density after 2h long-term operation,more than 10 times stable than the bare Cu2O photocathode.A PAMSB with a CuO/Cu2O photocathode achieves a maximum power density up to 22.67 mW cm-2and a hydrogen yield rate up to 1.18 mL cm-2min-1,much higher than those obtained with a bare Cu2O photocathode.This study offers a simple and convenient electrochemical strategy for in-situ fabrication of CuO/Cu2O heterojunction photocathodes,and also demonstrate the feasibility of PAMSBs as a power source and a hydrogen generator,which lays foundation for its future marine application.展开更多
基金the financialsupport from the Key Research and Development Program of Hubei Province(2023BAB038)the Foundation of State Key Laboratory of Coal Combustion.
摘要In this study,the pyrolysis and combustion characteristics of sugar tar waste liquid(STWL)affected by different water contents and oxygen concentrations are studied by using a Thermogravimetric analysis,and the kinetic parameters of the pyrolysis and combustion are obtained by the Coats-Redfern integral method.The results show that both the pyrolysis process and the combustion process of the STWLs are divided into two stages under the different water contents and oxygen concentrations.The low and high temperature ranges for pyrolysis and combustion process are below 420℃ and 420-500℃ and below 400℃ and 400500℃,respectively.As the water contents increase,the pyrolysis initial temperature Ti,p gradually decreases and the comprehensive pyrolysis characteristic index D also decreases for the pyrolysis process.The Ti,p increases from 224℃to 350℃,and the index D decreases from 3.30×10-4to 0.811×10-4% 3·min-2·℃-3.The combustion ignition temperature Ti,c increases and the comprehensive combustion characteristic index S decreases.When the oxygen concentration increases,the ignition temperature and the burnout temperature remain almost constant,with variations of 3.6%and 2.0%,respectively.Besides,the pyrolysis and combustion process of the STWL obeys the stochastic nucleation and subsequent growth model,i.e.,[-ln(1-α)]4.These results are expected to provide some valuable guidance for organic waste liquid incineration treatment.
基金financial support of National Natural Science Foundation of China(52304060,52374211,52304190)the Shandong Natural Science Foundation(ZR2024QE029 and ZR2023QE117).
摘要In-situ combustion(ISC)has a huge potential in recovering heavy oil resources with a low environmental footprint.At the end of the ISC operation,a huge amount of thermal energy is left in the reservoir.By appropriately recovering the thermal energy in the depleted reservoirs after ISC operation,it could extend the economic life of the heavy oil reservoirs.This work investigated the potential of extracting heat using the cold water and CO2as the working fluids to advance the knowledge base regarding the thermal energy recovery and CO2storage in depleted ISC reservoirs.The extracted fluids are fed to the surface binary cycle for power generation or district heating.Simulation of ISC was performed to estimate the temperature,energy,and fluids distributions after 20 years of the oil production.An assessment of the energy remaining in the reservoir is performed.It is estimated that a total of 3×1014 J thermal energy was left underground after ISC operation in the typical five-spot well pattern.Subsequently,an examination of the potentially recoverable energy from the post ISC operation is performed.Cold water and CO2are recirculated into the reservoir for energy recovery.The results indicates that the heavy oil reservoir after ISC operation can be regarded as an artificial geothermal system for subsurface thermal energy extraction.As the water circulation rate increases from 200 m3/day and to 400 m3/day and 600 m3/day,the average reservoir temperature is declined to 95℃,79℃,and 71℃,respectively.Meanwhile,the corresponding thermal energy recovery factors are 48%,63%,and 77%,respectively.Larger water circulation rate can generate high energy output and high energy recovery in the post ISC operation.The thermal energy recovery could prolong the energy production to 15 to 20 years in a depleted reservoir.Except for thermal energy extraction,a total of 6100 tons of CO2can be sequestrated underground by using the CO2as the working fluids in the five spot well pattern.The numerical investigation in this study indicate that huge energy extraction potential and CO2storage can be achieved at the full field scale.Utilization of subsurface thermal energy after the ISC operation is a beneficial choice to offset the operating costs,reduce the CO2emission and extend the economic life of reservoir.
摘要Single-atom catalysts possess the ability to effectively modulate the chemical environment of active sites,thereby synergistically enhancing catalytic reaction activity due to their unique electronic properties.In this study,single-atom Ni-doped CeO2-supported Pd catalysts were designed and synthesized.The introduction of single-atom Ni induced lattice distortion in the CeO2 support,resulting in an increased concentration of oxygen vacancies on the surface.This increase in oxygen vacancies enhances the strong metal-support interactions between Pd and the support.Under the intensified metal-support interaction effect,Pd species tend to transfer more electrons to Ni atoms and adjacent O atoms,leading to a higher proportion of high oxidation states(Pd4+)in PdOx species.The presence of high-valent Pd4+and oxygen vacancies synergically enhances the activation of C-H bonds in methane and the adsorption and dissociation of oxygen,significantly improving the overall catalytic activity of methane combustion.This study provides a critical theoretical foundation and practical guidance for the design and optimization of clean energy catalysts.
基金supported by the National Key R&D Program of China(Nos.2022YFB3504101 and 2022YFB3506200)the National Natural Science Foundation of China(Nos.22322601 and 22425601)the R&D Program of Beijing Municipal Education Commission(No.KZ202210005011)。
摘要The inherent irreducibility and limited sulfur dioxide tolerance of zeolites constrain oxygen exchange efficiency in palladium/zeolite catalysts,which can adversely affect their performance in methane combustion.Herein,a novel molecular sieve(Silicate-1,denoted as S-1)catalyst functionalized with rare earth oxide sites was developed for catalytic methane combustion.Although both Pd/S-1@CeO2-30(in which CeO2content was 30 wt.%)and Pd/S-1 catalysts demonstrated comparable initial catalytic activities,the Pd/S-1@CeO2-30 sample achieved a methane reaction rate of 114.0μmol/(gPd·s)and the highest TOFPd(0.033s-1),with a 90%methane conversion at 424℃ at a space velocity of 20,000 mL/(g h).The CeO2shell in Pd/S-1@CeO2-30 exhibited the superior longterm stability that was attributed to the redox property of CeO2,which could facilitate the provision of abundant oxygen species.As a result,the Pd/S-1@CeO2-30 catalyst maintained stable performance in 10,000-ppm CH4methane combustion at 400℃ and retained a high CH4conversion efficiency even under exposure to 50 ppm SO2.Similarly,Ce0.6Zr0.4O2or Sm2O3shell also demonstrated comparable SO2resistance.Detailed characterization results revealed that CeO2acted as an exceptional redox center,significantly enhanced SO2adsorption,and effectively inhibited the poisoning of the active PdO sites by SO2,leading to a notable improvement in sulfur dioxide tolerance.These findings highlighted the critical role of the core-shell structure in enhancing catalyst resistance to SO2poisoning during methane combustion.The present work provides valuable insights into the appropriate designing of advanced core-shell catalysts with improved durability and performance in the sulfur dioxide-containing environments.
基金supported by JST,grant number JPMJFS2132JST SPRING,grant number JPMJSP2136by an external research grant from Mitsubishi Fuso Truck&Bus Corporation。
摘要Engineering the pore structure of biomass-derived activated carbons is critical for optimizing their performance in adsorptionbased applications.This study demonstrates for the first time that washing hydrochars in solvents of different polarity before activation is a simple yet powerful strategy to tailor pore size distribution.Hydrochar is produced from spent coffee grounds via hydrothermal carbonization,followed by washing in various solvents and activation in KOH.This results in carbons with a very large surface area(~2700 m2/g),and washing is demonstrated to significantly increase product yield.Furthermore,washing in non-polar or mixed-polarity solvents removes long-chain carboxylic acids and esters from the hydrochar,promoting the development of narrow micropores while suppressing mesopore formation.To illustrate the impact of this structural control of porous carbons,post-combustion CO2capture is investigated as a case study.Narrower pore size distribution enhances CO2uptake,significantly improving capacity from 2.8 mmol/g for unwashed samples to 3.8 mmol/g for acetone-washed samples.Interestingly,moderate pore size(9-12Å)is shown to be optimal for CO2:N2 selectivity,while smaller pores result in lower selectivity due to stronger interactions between N2 and the pore walls.These findings highlight the potential role of solvent washing in directing pore architecture of hydrochars for adsorption-based carbon capture technologies and beyond.
摘要Engineering the morphology of the support is effective in tuning the redox properties of active metals for efficient catalytic methane combustion via tailoring the metal-support interaction.Herein,uniform Ir nanoparticles supported on anatase TiO2with different morphologies predominantly exposing{100},{101},and{001}planes were synthesized and tested for methane combustion.The CH4 catalytic activity shows a remarkable TiO2-facet-dependent effect and follows the order of Ir/TiO2-{100}>Ir/TiO2-{101}>>Ir/TiO2-{001}.Detailed characterizations and DFT calculations reveal that compared with Ir-TiO2-{101}and Ir-TiO2-{001}interfaces,the superior Ir-TiO2-{100}interface facilitates the generation of electron-rich Ir species through more profound charge transfer from TiO2-{100}to Ir atoms.The electron-rich Ir structure,featuring abundant defect oxygen vacancies,significantly enhances the redox properties of active Ir species and reduces the activation energy for breaking the initial C-H bond in CH4,resulting in the superior catalytic activity for methane combustion.These findings deepen fundamental insights into the TiO2-facet-dependent reactivity of different Ir/TiO2nanomaterials in methane oxidation and pave the way for designing efficient Ir-based methane oxidation catalysts.
摘要为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P2O5∶K2O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260全秸秆茬地洁区旋耕智能施肥播种机和3ZF-4(200)中耕追肥机,设置7种施肥模式(30 cm+15 cm宽窄行种植):以尿素4次分施(N 240 kg hm-2,基肥∶分蘖肥∶拔节肥∶孕穗肥=5∶1∶2∶2,窄行基施,追肥全田撒施)为对照(CK);减氮15%(N 204 kg hm-2)条件下设置6种处理:M1(100%SRF窄行基施);M2(60%SRF窄行基施+40%U拔节期窄行撒施);M3(60%SRF窄行基施+40%U返青期宽行条施);M4(60%SRF窄行基施+40%SRF返青期窄行撒施);M5(60%SRF窄行基施+40%SRF返青期宽行条施);M4+5(60%SRF窄行基施+20%SRF返青期宽行条施+20%SRF返青期窄行撒施)。研究比较不同施肥模式对小麦产量效益、根系形态生理、氮素利用效率及N2O排放的影响。结果表明,与CK相比,M2~M5处理提高了小麦产量(4.0%~19.0%)和经济效益(13.7%~35.7%),其中M4和M5处理表现最优,分别增产14.1%和19.0%,经济效益提升34.5%和35.7%。这些处理明显改善了根系特性(根干重密度增加9.7%~111.8%,根系活力和氧化力分别提高6.8%~52.0%和4.2%~44.2%),降低N2O累积排放量22.6%~34.5%,提高0~20 cm土层硝态氮含量11.2%~40.0%。在氮素利用方面,M2~M5处理均提高了籽粒氮素积累量、花后氮素积累量及其对籽粒氮素的贡献率,氮肥利用效率指标(包括偏生产力、农学效率和表观利用率)分别显著提升了22.4%~40.0%、29.7%~74.3%和9.41~18.77个百分点。值得注意的是,M4和M5处理表现出最优的综合效益:N2O累积排放量降幅最大(分别达27.0%和34.5%),氮肥表观利用率2季均维持在43.0%以上(均值分别为43.5%和46.8%),同时在生育后期保持较高的根系活性和耕层无机氮含量。相比之下,M1处理虽然实现了最大的N2O减排效果(降幅35.9%),但导致减产10.4%和经济效益下降10.8%,且氮肥利用效率呈现不稳定的年际变化特征。而优化处理M4+5进一步改善了根系形态生理特性,并提高氮肥表观利用率和籽粒氮素积累量。综上,减氮15%条件下(N 204 kg hm-2),缓混肥2次施用处理(M4和M5)能实现产量、经济效益、氮肥利用效率和N2O减排的协同提高,并以追肥深施处理(M5)效应更强。本研究为稻茬小麦缓释肥减氮优化高效应用提供重要理论依据。
基金financially supported by National Natural Science Foundation of China(Nos.22179067 and 22279069)Major Fundamental Research Program of Natural Science Foundation of Shandong Province(No.ZR2022ZD10)。
摘要Photo-assisted Mg/seawater batteries(PAMSBs)are attractive power source for marine equipment due to the advan tage of simultaneous generation of electricity an d hydrogen from seawater.Nonetheless,the serious photocorrosion of photocathodes results in dissatisfactory battery performan ce,which substantially hinder their practical applications.Herein,we design a CuO/Cu2O heterostructure as the photocathode of PAMSBs via a facile in-situ electrochemical strategy,successfully enhance the photo-stability of bare Cu2O.During half-cell photoelectrochemical water splitting,the newly-developed CuO/Cu2O photocathode reveals a photo-current density about 2.2 mA cm-2at 0 V(vs.RHE)and enables nearly 100% retention of the initial photocurrent density after 2h long-term operation,more than 10 times stable than the bare Cu2O photocathode.A PAMSB with a CuO/Cu2O photocathode achieves a maximum power density up to 22.67 mW cm-2and a hydrogen yield rate up to 1.18 mL cm-2min-1,much higher than those obtained with a bare Cu2O photocathode.This study offers a simple and convenient electrochemical strategy for in-situ fabrication of CuO/Cu2O heterojunction photocathodes,and also demonstrate the feasibility of PAMSBs as a power source and a hydrogen generator,which lays foundation for its future marine application.