Understanding the response of the Earth system to varying concentrations of carbon dioxide(CO_(2))is critical for projecting possible future climate change and for providing insight into mitigation and adaptation stra...Understanding the response of the Earth system to varying concentrations of carbon dioxide(CO_(2))is critical for projecting possible future climate change and for providing insight into mitigation and adaptation strategies in the near future.In this study,we generate a dataset by conducting an experiment involving carbon dioxide removal(CDR)—a potential way to suppress global warming—using the Chinese Academy of Sciences Earth System Model version 2.0(CASESM2.0).A preliminary evaluation is provided.The model is integrated from 200–340 years as a 1%yr^(−1) CO_(2) concentration increase experiment,and then to~478 years as a carbon dioxide removal experiment until CO_(2) returns to its original value.Finally,another 80 years is integrated in which CO_(2) is kept constant.Changes in the 2-m temperature,precipitation,sea surface temperature,ocean temperature,Atlantic meridional overturning circulation(AMOC),and sea surface height are all analyzed.In the ramp-up period,the global mean 2-m temperature and precipitation both increase while the AMOC weakens.Values of all the above variables change in the opposite direction in the ramp-down period,with a delayed peak relative to the CO_(2) peak.After CO_(2) returns to its original value,the global mean 2-m temperature is still~1 K higher than in the original state,and precipitation is~0.07 mm d^(–1) higher.At the end of the simulation,there is a~0.5°C increase in ocean temperature and a 1 Sv weakening of the AMOC.Our model simulation produces similar results to those of comparable experiments previously reported in the literature.展开更多
Fruits of persimmon (Diospyros kaki cv. Mopanshi) were used to investigate the effects of different concentrations of carbon dioxide (CO 2) gas on removing astringency after harvest. Treatment of 95% concentration of...Fruits of persimmon (Diospyros kaki cv. Mopanshi) were used to investigate the effects of different concentrations of carbon dioxide (CO 2) gas on removing astringency after harvest. Treatment of 95% concentration of CO 2 gas gave the best results; fruits turned non-astringent after 20 h, and kept the fruit firm for 7 d at room temperature. Fruits, treated with 85 and 90% concentration of CO 2 gas, turned non-astringent after 2428 h, and the firmness-keeping stage was 56 d at room temperature. While the CO 2 gas was at 80, 70 and 60%, the de-astringency period was 48, 72 and 96 h, and the corresponding firmness-keeping stage was 3, 2 and 1 d, respectively. Fruits, treated with 50% concentration of CO 2 gas, remained astringent.展开更多
Magnesium oxide was found to have high-phosphate-affinity as an effective component to enhance the phosphate removal ability of common adsorbent materials.However,the currently prepared MgO-based hybrid adsorbents by ...Magnesium oxide was found to have high-phosphate-affinity as an effective component to enhance the phosphate removal ability of common adsorbent materials.However,the currently prepared MgO-based hybrid adsorbents by conventional methods still suffer from the limited low loading of MgO and inferior removal performances,much far away from practical application.In this study,an ingenious carbon coated MgO nanocomposite is designed by directly burning magnesium in CO_(2),a well-known textbook reaction.X-ray diffraction analysis,scanning electron microscope and aberration-corrected high-resolution transmission electron microscope demonstrate the sample is well prepared.Consequently,the high content of nanosized MgO combined with defect-rich carbon layer brings unprecedented phosphate removal capacity of 1135.0 mg/g,removal rate of 99% and benign compatibility with coexisting anions and solution pH.Furthermore,the removal mechanism is also investigated in detail by characterizing the sample before and after adsorption.展开更多
Artificial CO_(2)removal from the atmosphere(also referred to as negative CO_(2)emissions)has been proposed as a potential means to counteract anthropogenic climate change.Here we use an Earth system model to examine ...Artificial CO_(2)removal from the atmosphere(also referred to as negative CO_(2)emissions)has been proposed as a potential means to counteract anthropogenic climate change.Here we use an Earth system model to examine the response of ocean acidification to idealized atmospheric CO_(2)removal scenarios.In our simulations,atmospheric CO_(2)is assumed to increase at a rate of 1%per year to four times its pre-industrial value and then decreases to the pre-industrial level at a rate of 0.5%,1%,2%per year,respectively.Our results show that the annual mean state of surface ocean carbonate chemistry fields including hydrogen ion concentration([H^(+)]),pH and aragonite saturation state respond quickly to removal of atmospheric CO_(2).However,the change of seasonal cycle in carbonate chemistry lags behind the decline in atmospheric CO_(2).When CO_(2)returns to the pre-industrial level,over some parts of the ocean,relative to the pre-industrial state,the seasonal amplitude of carbonate chemistry fields is substantially larger.Simulation results also show that changes in deep ocean carbonate chemistry substantially lag behind atmospheric CO_(2)change.When CO_(2)returns to its pre-industrial value,the whole-ocean acidity measured by[H^(+)]is 15%-18%larger than the pre-industrial level,depending on the rate of CO_(2)decrease.Our study demonstrates that even if atmospheric CO_(2)can be lowered in the future as a result of net negative CO_(2)emissions,the recovery of some aspects of ocean acidification would take decades to centuries,which would have important implications for the resilience of marine ecosystems.展开更多
The UN International Panel Environment Programme (“UNEP”), 2023 Emissions Gap Report urgently presses the global community to adopt a two-pronged approach to reduce atmospheric concentration of CO2—expedite efforts...The UN International Panel Environment Programme (“UNEP”), 2023 Emissions Gap Report urgently presses the global community to adopt a two-pronged approach to reduce atmospheric concentration of CO2—expedite efforts to reduce annual CO2 emissions;and increase investment in large-scale carbon dioxide removal (“CDR”) projects. The Gap Report sets a 2050 target of six-gigatons annual land-based CDR. Our proposed agroforestry project will convert thirty-five-million acres of rangeland in the American Great Plains to silvopasture, combining growing trees and raising livestock. Employing agroforestry interests 61% of Great Plaints farmers/ranchers recently surveyed. The Project plans to annually collect + six-gigatons CO2 equiv. of fallen leaves and store the stable carbon-rich biomass underground for centuries. The purpose of this paper is to describe the framework for formation of a global partnership at the local, regional, and international levels to coordinate public and private financing mechanisms, implement, and operate a large-scale CDR Project that will meaningfully impact the global effort to mitigate climate change.展开更多
The carbon dioxide removal system is the most critical system for controlling CO2 mass concentration in long-term manned spacecraft.In order to ensure the controlling CO2 mass concentration in the cabin within the all...The carbon dioxide removal system is the most critical system for controlling CO2 mass concentration in long-term manned spacecraft.In order to ensure the controlling CO2 mass concentration in the cabin within the allowable range,the state of CO2 removal system needs to be estimated in real time.In this paper,the mathematical model is firstly established that describes the actual system conditions and then the Galerkin-based extended Kalman filter algorithm is proposed for the estimation of the state of CO2.This method transforms partial differential equation to ordinary differential equation by using Galerkin approaching method,and then carries out the state estimation by using extended Kalman filter.Simulation experiments were performed with the qualification of the actual manned space mission.The simulation results show that the proposed method can effectively estimate the system state while avoiding the problem of dimensional explosion,and has strong robustness regarding measurement noise.Thus,this method can establish a basis for system fault diagnosis and fault positioning.展开更多
1.Introduction Carbon mitigation engineering,also known as climate engineering internationally,is an umbrella term of engineering measures targeted at combating climate change and achieving carbon neutrality.Climate o...1.Introduction Carbon mitigation engineering,also known as climate engineering internationally,is an umbrella term of engineering measures targeted at combating climate change and achieving carbon neutrality.Climate or mitigation engineering can be commonly divided into three categories based on technological principles[1]:(1)carbon dioxide removal(CDR),which has the potential to achieve negative emissions by removing atmospheric carbon dioxide[2].展开更多
2023年6月16日,欧洲危重症医学会(the European Society of Intensive Care Medicine,ESICM)在《重症监护医学杂志(Intensive Care Medicine,ICM)》发布了《ESICM急性呼吸窘迫综合征指南:定义、表型和呼吸支持策略》(以下简称2023版指南...2023年6月16日,欧洲危重症医学会(the European Society of Intensive Care Medicine,ESICM)在《重症监护医学杂志(Intensive Care Medicine,ICM)》发布了《ESICM急性呼吸窘迫综合征指南:定义、表型和呼吸支持策略》(以下简称2023版指南)。与2017版指南相比,2023版指南增加了“定义”和“表型”两个领域,但只是进行了阐述,并未给出推荐意见;针对“呼吸支持策略”,2023版指南增加了“经鼻高流量氧疗(high flow nasal cannula oxygen,HFNO)”“无创通气(noninvasive ventilation,NIV)”“神经肌肉阻滞剂”和“体外二氧化碳清除(extracorporeal carbon dioxide removal,ECCO_(2)R)”四个模块,对呼吸支持策略给出了相应的推荐意见;同时还针对2019年新型冠状病毒感染(COVID-19)患者给出了额外的推荐意见。但2023版指南并未明确给出ARDS新定义,2023年7月24日《美国呼吸与危重病医学杂志(American Journal of Respiratory and Critical Care Medicine,AJRCCM)》给出了ARDS的全球新定义,填补了2023版指南的定义部分。本文结合2023版指南及ARDS全球新定义对指南进行了解读,以供重症同仁参考。展开更多
基金jointly supported by the National Key Research and Development Program of China (Grant No. 2022YFC3105000)the Youth Innovation Promotion Association of CAS (2022074)+3 种基金the National Natural Science Foundation of China (Grant Nos. 42005123, 42275173 and 41706028)the National Key Research and Development Program of China(2022YFE0106500)the 7th Youth Talent Support Project of Ningxia Hui Autonomous Region Association for Science and TechnologyNational Key Scientific and Technological Infrastructure project ‘‘Earth System Science Numerical Simulator Facility’’(EarthLab) for supporting the simulations in this study
文摘Understanding the response of the Earth system to varying concentrations of carbon dioxide(CO_(2))is critical for projecting possible future climate change and for providing insight into mitigation and adaptation strategies in the near future.In this study,we generate a dataset by conducting an experiment involving carbon dioxide removal(CDR)—a potential way to suppress global warming—using the Chinese Academy of Sciences Earth System Model version 2.0(CASESM2.0).A preliminary evaluation is provided.The model is integrated from 200–340 years as a 1%yr^(−1) CO_(2) concentration increase experiment,and then to~478 years as a carbon dioxide removal experiment until CO_(2) returns to its original value.Finally,another 80 years is integrated in which CO_(2) is kept constant.Changes in the 2-m temperature,precipitation,sea surface temperature,ocean temperature,Atlantic meridional overturning circulation(AMOC),and sea surface height are all analyzed.In the ramp-up period,the global mean 2-m temperature and precipitation both increase while the AMOC weakens.Values of all the above variables change in the opposite direction in the ramp-down period,with a delayed peak relative to the CO_(2) peak.After CO_(2) returns to its original value,the global mean 2-m temperature is still~1 K higher than in the original state,and precipitation is~0.07 mm d^(–1) higher.At the end of the simulation,there is a~0.5°C increase in ocean temperature and a 1 Sv weakening of the AMOC.Our model simulation produces similar results to those of comparable experiments previously reported in the literature.
文摘Fruits of persimmon (Diospyros kaki cv. Mopanshi) were used to investigate the effects of different concentrations of carbon dioxide (CO 2) gas on removing astringency after harvest. Treatment of 95% concentration of CO 2 gas gave the best results; fruits turned non-astringent after 20 h, and kept the fruit firm for 7 d at room temperature. Fruits, treated with 85 and 90% concentration of CO 2 gas, turned non-astringent after 2428 h, and the firmness-keeping stage was 56 d at room temperature. While the CO 2 gas was at 80, 70 and 60%, the de-astringency period was 48, 72 and 96 h, and the corresponding firmness-keeping stage was 3, 2 and 1 d, respectively. Fruits, treated with 50% concentration of CO 2 gas, remained astringent.
基金This study was supported by the National Key R&D Program of China through grant 2018YFC1900102A portion of this work was conducted at Argonne National Laboratory.Argonne National Laboratory is operated for DOE Office of Science by UChicago Argonne,LLC,under contract number DE-AC02-06CH11357This study was performed,in part,at the Center for Nanoscale Materials,a US Department of Energy Office of Science User Facility,and supported by the US Department of Energy,Office of Science,under Contract No.DE-AC02-06CH11357.
文摘Magnesium oxide was found to have high-phosphate-affinity as an effective component to enhance the phosphate removal ability of common adsorbent materials.However,the currently prepared MgO-based hybrid adsorbents by conventional methods still suffer from the limited low loading of MgO and inferior removal performances,much far away from practical application.In this study,an ingenious carbon coated MgO nanocomposite is designed by directly burning magnesium in CO_(2),a well-known textbook reaction.X-ray diffraction analysis,scanning electron microscope and aberration-corrected high-resolution transmission electron microscope demonstrate the sample is well prepared.Consequently,the high content of nanosized MgO combined with defect-rich carbon layer brings unprecedented phosphate removal capacity of 1135.0 mg/g,removal rate of 99% and benign compatibility with coexisting anions and solution pH.Furthermore,the removal mechanism is also investigated in detail by characterizing the sample before and after adsorption.
基金supported by the National Natural Science Foundation of China(Nos.41975103,42275179,22022611,and 42005027)the Zhejiang Provincial Natural Science Foundation of China(No.LQ20D050003)。
文摘Artificial CO_(2)removal from the atmosphere(also referred to as negative CO_(2)emissions)has been proposed as a potential means to counteract anthropogenic climate change.Here we use an Earth system model to examine the response of ocean acidification to idealized atmospheric CO_(2)removal scenarios.In our simulations,atmospheric CO_(2)is assumed to increase at a rate of 1%per year to four times its pre-industrial value and then decreases to the pre-industrial level at a rate of 0.5%,1%,2%per year,respectively.Our results show that the annual mean state of surface ocean carbonate chemistry fields including hydrogen ion concentration([H^(+)]),pH and aragonite saturation state respond quickly to removal of atmospheric CO_(2).However,the change of seasonal cycle in carbonate chemistry lags behind the decline in atmospheric CO_(2).When CO_(2)returns to the pre-industrial level,over some parts of the ocean,relative to the pre-industrial state,the seasonal amplitude of carbonate chemistry fields is substantially larger.Simulation results also show that changes in deep ocean carbonate chemistry substantially lag behind atmospheric CO_(2)change.When CO_(2)returns to its pre-industrial value,the whole-ocean acidity measured by[H^(+)]is 15%-18%larger than the pre-industrial level,depending on the rate of CO_(2)decrease.Our study demonstrates that even if atmospheric CO_(2)can be lowered in the future as a result of net negative CO_(2)emissions,the recovery of some aspects of ocean acidification would take decades to centuries,which would have important implications for the resilience of marine ecosystems.
文摘The UN International Panel Environment Programme (“UNEP”), 2023 Emissions Gap Report urgently presses the global community to adopt a two-pronged approach to reduce atmospheric concentration of CO2—expedite efforts to reduce annual CO2 emissions;and increase investment in large-scale carbon dioxide removal (“CDR”) projects. The Gap Report sets a 2050 target of six-gigatons annual land-based CDR. Our proposed agroforestry project will convert thirty-five-million acres of rangeland in the American Great Plains to silvopasture, combining growing trees and raising livestock. Employing agroforestry interests 61% of Great Plaints farmers/ranchers recently surveyed. The Project plans to annually collect + six-gigatons CO2 equiv. of fallen leaves and store the stable carbon-rich biomass underground for centuries. The purpose of this paper is to describe the framework for formation of a global partnership at the local, regional, and international levels to coordinate public and private financing mechanisms, implement, and operate a large-scale CDR Project that will meaningfully impact the global effort to mitigate climate change.
基金Project(050403)supported by Pre-research Project in the Manned Space Filed of China。
文摘The carbon dioxide removal system is the most critical system for controlling CO2 mass concentration in long-term manned spacecraft.In order to ensure the controlling CO2 mass concentration in the cabin within the allowable range,the state of CO2 removal system needs to be estimated in real time.In this paper,the mathematical model is firstly established that describes the actual system conditions and then the Galerkin-based extended Kalman filter algorithm is proposed for the estimation of the state of CO2.This method transforms partial differential equation to ordinary differential equation by using Galerkin approaching method,and then carries out the state estimation by using extended Kalman filter.Simulation experiments were performed with the qualification of the actual manned space mission.The simulation results show that the proposed method can effectively estimate the system state while avoiding the problem of dimensional explosion,and has strong robustness regarding measurement noise.Thus,this method can establish a basis for system fault diagnosis and fault positioning.
基金financial support from the National Natural Science Foundation of China(71521002)National Key Research and Development Program of China(2016YFA0602603)。
文摘1.Introduction Carbon mitigation engineering,also known as climate engineering internationally,is an umbrella term of engineering measures targeted at combating climate change and achieving carbon neutrality.Climate or mitigation engineering can be commonly divided into three categories based on technological principles[1]:(1)carbon dioxide removal(CDR),which has the potential to achieve negative emissions by removing atmospheric carbon dioxide[2].
文摘2023年6月16日,欧洲危重症医学会(the European Society of Intensive Care Medicine,ESICM)在《重症监护医学杂志(Intensive Care Medicine,ICM)》发布了《ESICM急性呼吸窘迫综合征指南:定义、表型和呼吸支持策略》(以下简称2023版指南)。与2017版指南相比,2023版指南增加了“定义”和“表型”两个领域,但只是进行了阐述,并未给出推荐意见;针对“呼吸支持策略”,2023版指南增加了“经鼻高流量氧疗(high flow nasal cannula oxygen,HFNO)”“无创通气(noninvasive ventilation,NIV)”“神经肌肉阻滞剂”和“体外二氧化碳清除(extracorporeal carbon dioxide removal,ECCO_(2)R)”四个模块,对呼吸支持策略给出了相应的推荐意见;同时还针对2019年新型冠状病毒感染(COVID-19)患者给出了额外的推荐意见。但2023版指南并未明确给出ARDS新定义,2023年7月24日《美国呼吸与危重病医学杂志(American Journal of Respiratory and Critical Care Medicine,AJRCCM)》给出了ARDS的全球新定义,填补了2023版指南的定义部分。本文结合2023版指南及ARDS全球新定义对指南进行了解读,以供重症同仁参考。
