To explain the influence mechanism of MgO on the consolidation and reduction characteristics of roasted iron pellets,the properties and structure of pellets were investigated from multi-dimensions.It indicated that th...To explain the influence mechanism of MgO on the consolidation and reduction characteristics of roasted iron pellets,the properties and structure of pellets were investigated from multi-dimensions.It indicated that the MgO addition decreased the reduction swelling index(RSI)and reduction degree of pellets in both CO and H_(2)atmospheres.During the stepwise reduction process of Fe2O3→Fe3O4→FeO,the reduction behaviour of pellets in CO and H_(2)was similar,while the reduction rate of pellets in H_(2)atmosphere was almost twice as high as that in CO atmosphere.During the stepwise reduction process of FeO→Fe,the RSI of pellets showed a logarithmic increase in CO atmosphere and a linear decrease in H_(2)atmosphere.As investigated by first-principles calculations,C and Fe mainly formed chemical bonds,and the CO reduction process released energy,promoting the formation of iron whiskers.However,H and Fe produced weak physical adsorption,and the H_(2)reduction process was endothermic,inhibiting the generation of iron whiskers.With Mg2+doping in FexO,the nucleation region of iron whiskers expanded in CO reduction process,and the morphology of iron whiskers transformed from“slender”to“stocky,”reducing RSI of the pellets.展开更多
Although atmospheric CO_(2) observations are becoming increasingly widespread in China,the identification of CO_(2) emission sources is still scarce,especially in undeveloped Central China.To effectively address this ...Although atmospheric CO_(2) observations are becoming increasingly widespread in China,the identification of CO_(2) emission sources is still scarce,especially in undeveloped Central China.To effectively address this issue,in a typical site in Central China,the simultaneous measurements of atmospheric CO_(2),CO,andδ^(13)C were conducted,and the characteristics of CO_(2) emission sources were systematically investigated based on the relationships among CO_(2),CO,andδ^(13)C.The average CO_(2)/CO ratio of winter increased from 52.4 ppm/ppm during 2018–2020 to 65.1 ppm/ppm during 2021–2022,which confirmed the improvement of energy consumption efficiency in China.Air-mass transportation from central China and Yangtze River Delta regions contributed largely to higher CO_(2)/CO ratios in 2021–2022.A highermean CO_(2)/CO ratio appeared during the morning rush hours(60.3 ppm/ppm)than in the afternoon rush hours(51.4 ppm/ppm)in winter.In addition,the meanδ^(13)C value of CO_(2) sources(δ^(13)Cs)also displayed more negative values during the morning rush hours(-28.3‰)than the afternoon rush hours(-22.2‰),suggesting the significant influence of vehicle and natural gas usage at themorning rush hours and the impact of straw burning in the afternoon rush hours.The meanδ^(13)Cs was-24.7‰for winter and-21.9‰for vegetation season,implying the main contribution of coal in winter and the impact of C4 plants during the vegetation season.The contribution of biogenic respiration CO_(2) was inferred to exceed 50%during the nighttime of summer according to the obtained meanδ^(13)C value of biogenic respiration CO_(2),which was calculated to be-21.4‰.展开更多
Exploration of efficient and stable photocatalysts to mimic natural leaves for the conversion of atmospheric CO_(2)into hydrocarbons utilizing solar light is very important but remains a major challenge.Herein,we repo...Exploration of efficient and stable photocatalysts to mimic natural leaves for the conversion of atmospheric CO_(2)into hydrocarbons utilizing solar light is very important but remains a major challenge.Herein,we report the design of four novel metal-salen-incorporated conjugated microporous polymers as robust artificial leaves for photoreduction of atmospheric CO_(2)with gaseous water.Owing to the rich nitrogen and oxygen moieties in the polymeric frameworks,they show a maximum CO_(2)adsorption capacity of 46.1 cm3 g^(−1)and adsorption selectivity for CO_(2)/N_(2)of up to 82 at 273 K.Under air atmosphere and simulated solar light(100mWcm^(−2)),TEPT-Zn shows an excellent CO yield of 304.96μmol h^(−1)g^(−1)with a selectivity of approximately 100%,which represents one of the best results in terms of organic photocatalysts for gas-phase CO_(2)photoreduction so far.Furthermore,only small degradation in the CO yield is observed even after 120-h continuous illumination.More importantly,a good CO yield of 152.52μmol g^(−1)was achieved by directly exposing the photocatalytic reaction of TEPT-Zn in an outdoor environment for 3 h(25-28℃,52.3±7.9mWcm^(−2)).This work provides an avenue for the continued development of advanced polymers toward gas-phase photoconversion of CO_(2)from air.展开更多
China is the largest emitter of anthropogenic CO_(2) globally,with its cities recognized as significant emission hotspots.Consequently,evaluating anthropogenic CO_(2) emissions and the carbon neutral capability(CNC)of...China is the largest emitter of anthropogenic CO_(2) globally,with its cities recognized as significant emission hotspots.Consequently,evaluating anthropogenic CO_(2) emissions and the carbon neutral capability(CNC)of Chinese cities is critical for climate change mitigation.Despite this importance,no studies to date have assessed recent and future city-scale CNCs using the top-down atmospheric inversion approach,revealing substantial knowledge gaps regarding regional CO_(2) budgets.To address these issues,this research focused on Hangzhou,a megacity known for having the highest forest cover among China’s provincial capitals,as study region.Year-round atmospheric CO_(2) concentration measurements were conducted from December 2020 to November 2021 at two sites:one urban and one suburban.These observations,along with their difference,were utilized to derive city-scale posterior anthropogenic CO_(2) emissions and to evaluate recent and future CNCs.Our key findings are as follows:(1)The manufacturing industry,energy industry and oil refineries/transformation industry were identified as the largest contributors to urban-suburban CO_(2) difference,accounting for 36.5%,21.3%,and 16.6%,respectively.Additionally,82.5%,65.2%,81.2%and 86.3%of total anthropogenic CO_(2) enhancements were attributed to emissions within Hangzhou city in winter,spring,summer and autumn,respectively.(2)The posterior annual anthropogenic CO_(2) emission for Hangzhouwas estimated at 4.65(±0.72)×10^(10) kg/a,indicating significant biases among different prior CO_(2) emission inventories.The annual biological CO_(2) sink,derived from multiple products,was estimated at-0.48(±0.16)×10^(10) kg.(3)The calculated CNC for 2021was 10.3%±3.4%,highlighting a substantial gap towards achieving full carbon neutrality.Considering potential increases in ecosystem carbon sinks due to forest age and uncertainties from climate change,it was predicted that at least 65.2%-82.6%of anthropogenic CO_(2) emissions must be reduced to achieve the goal of full carbon neutrality by year of 2060.展开更多
Sweet cherries ( Prunus avium L. cv. Napoleon) were stored in controlled atmospheres (CA) of high O(2) (70% O(2) + 0% CO(2)) or high CO(2) (5% O(2) + 10% CO(2)), in modified atmosphere package (MAP, (13% - 18%) O(2) +...Sweet cherries ( Prunus avium L. cv. Napoleon) were stored in controlled atmospheres (CA) of high O(2) (70% O(2) + 0% CO(2)) or high CO(2) (5% O(2) + 10% CO(2)), in modified atmosphere package (MAP, (13% - 18%) O(2) + (2% -4%) CO(2)) and in air (control) at 1 degreesC to investigate the effects of different O(2) and CO(2) concentrations on physiological properties, quality and storability of the fruits during storage. The results indicated that compared with other treatments, CA with high O(2) concentration decreased fruit decay and ethanol content, but increased the accumulation of malondialdehyde (MDA) and stimulated browning. CA with high CO(2) concentration inhibited polyphenol oxidase (PPO) activity, reduced MDA content, maintained vitamin C content and firmness, decreased fruit decay and browning. Soluble solids contents (SSC) were not significantly affected by different atmosphere treatments. 'Napoleon' fruits stored in 5% O(2) + 10% CO(2) for as long as 80 d were of good quality, but only 40, 20 and 30 d stored in MAP, 70% O(2) + 0% CO(2) and air, re-spectively.展开更多
[ Objective ] The paper was to study the effect of controlled atmosphere stress of carbon dioxide （ CO2 ） on Superoxide dismutase （SOD） activity of in- sect, so as to analyze the biological mechanism of the action...[ Objective ] The paper was to study the effect of controlled atmosphere stress of carbon dioxide （ CO2 ） on Superoxide dismutase （SOD） activity of in- sect, so as to analyze the biological mechanism of the action of controlled atmosphere stress on insect. [ Method] Using nitrotetrazolium blue chloride （NBT） light reduction method, SOD activity of drugstore beetle （ Stegobium panlceum ）, cigarette beetle （ Lasioderma serricorne） and coffee bean beetle （Araecerus fasciculatus） was studied, and the stress response of the enzyme under controlled atmosphere stress of CO2 was analyzed. [ Result ] SOD activity of drugstore beetle, cigarette beetle and coffee bean beetle exposed to controlled atmosphere stress of high concentrations of CO2 for 3 and 6 h had certain degree of increase, and the activity sig- nificantly increased from 2.011±0.954,2.664±0.218 and 1.458±0.718 to 3. 135±0. 105,3.050±0.673 and 2.975±0.229 U/（per pest · 30 min） after treat- ment for 6 h. [ Conclusion] Controlled atmosphere stress of high concentrations of CO2 had certain activation effect on SOD activity of storage pest in Chinese me- dicinal material within the context of sub-lethal events. The results could enrich the insecticidal mechanism of controlled atmosphere and theoretical system of analy- sis on insect resistance to controlled atmosphere.展开更多
基金support from the National Natural Science Foundation of China(52174290).
文摘To explain the influence mechanism of MgO on the consolidation and reduction characteristics of roasted iron pellets,the properties and structure of pellets were investigated from multi-dimensions.It indicated that the MgO addition decreased the reduction swelling index(RSI)and reduction degree of pellets in both CO and H_(2)atmospheres.During the stepwise reduction process of Fe2O3→Fe3O4→FeO,the reduction behaviour of pellets in CO and H_(2)was similar,while the reduction rate of pellets in H_(2)atmosphere was almost twice as high as that in CO atmosphere.During the stepwise reduction process of FeO→Fe,the RSI of pellets showed a logarithmic increase in CO atmosphere and a linear decrease in H_(2)atmosphere.As investigated by first-principles calculations,C and Fe mainly formed chemical bonds,and the CO reduction process released energy,promoting the formation of iron whiskers.However,H and Fe produced weak physical adsorption,and the H_(2)reduction process was endothermic,inhibiting the generation of iron whiskers.With Mg2+doping in FexO,the nucleation region of iron whiskers expanded in CO reduction process,and the morphology of iron whiskers transformed from“slender”to“stocky,”reducing RSI of the pellets.
基金supported by the National Natural Science Foundation of China(No.42105159)the Key Technologies Research and Development Program(No.2022YFF0606400)+2 种基金China Meteorological Administration“Research on value realization of climate ecological products”Youth Innovation Team Project(No.CMA2024QN15)Jiangxi Meteorological Technology Project(Nos.JX2021Z06,JX2022Z03,and JX2023Z03)the Joint Open Fund of the Institute of Atmospheric Environment,China Meteorological Administration,Shenyang and Key Laboratory of Agro-Meteorological Disasters of Liaoning Province(No.2024SYIAEKFZD05)。
文摘Although atmospheric CO_(2) observations are becoming increasingly widespread in China,the identification of CO_(2) emission sources is still scarce,especially in undeveloped Central China.To effectively address this issue,in a typical site in Central China,the simultaneous measurements of atmospheric CO_(2),CO,andδ^(13)C were conducted,and the characteristics of CO_(2) emission sources were systematically investigated based on the relationships among CO_(2),CO,andδ^(13)C.The average CO_(2)/CO ratio of winter increased from 52.4 ppm/ppm during 2018–2020 to 65.1 ppm/ppm during 2021–2022,which confirmed the improvement of energy consumption efficiency in China.Air-mass transportation from central China and Yangtze River Delta regions contributed largely to higher CO_(2)/CO ratios in 2021–2022.A highermean CO_(2)/CO ratio appeared during the morning rush hours(60.3 ppm/ppm)than in the afternoon rush hours(51.4 ppm/ppm)in winter.In addition,the meanδ^(13)C value of CO_(2) sources(δ^(13)Cs)also displayed more negative values during the morning rush hours(-28.3‰)than the afternoon rush hours(-22.2‰),suggesting the significant influence of vehicle and natural gas usage at themorning rush hours and the impact of straw burning in the afternoon rush hours.The meanδ^(13)Cs was-24.7‰for winter and-21.9‰for vegetation season,implying the main contribution of coal in winter and the impact of C4 plants during the vegetation season.The contribution of biogenic respiration CO_(2) was inferred to exceed 50%during the nighttime of summer according to the obtained meanδ^(13)C value of biogenic respiration CO_(2),which was calculated to be-21.4‰.
基金Research Foundation for Advanced Talents of East China University of Technology,Grant/Award Number:DHBK201927Excellent Youth Foundation of Jiangxi Scientific Committee,Grant/Award Number:20232ACB213012+2 种基金National Science Foundation for Young Scientists of China,Grant/Award Number:21905122National Science Foundation for Young Scientists,Grant/Award Number:21905147Jiangxi Talent Program,Grant/Award Number:DHSQT32022005.
文摘Exploration of efficient and stable photocatalysts to mimic natural leaves for the conversion of atmospheric CO_(2)into hydrocarbons utilizing solar light is very important but remains a major challenge.Herein,we report the design of four novel metal-salen-incorporated conjugated microporous polymers as robust artificial leaves for photoreduction of atmospheric CO_(2)with gaseous water.Owing to the rich nitrogen and oxygen moieties in the polymeric frameworks,they show a maximum CO_(2)adsorption capacity of 46.1 cm3 g^(−1)and adsorption selectivity for CO_(2)/N_(2)of up to 82 at 273 K.Under air atmosphere and simulated solar light(100mWcm^(−2)),TEPT-Zn shows an excellent CO yield of 304.96μmol h^(−1)g^(−1)with a selectivity of approximately 100%,which represents one of the best results in terms of organic photocatalysts for gas-phase CO_(2)photoreduction so far.Furthermore,only small degradation in the CO yield is observed even after 120-h continuous illumination.More importantly,a good CO yield of 152.52μmol g^(−1)was achieved by directly exposing the photocatalytic reaction of TEPT-Zn in an outdoor environment for 3 h(25-28℃,52.3±7.9mWcm^(−2)).This work provides an avenue for the continued development of advanced polymers toward gas-phase photoconversion of CO_(2)from air.
基金supported by the National Natural Science Foundation of China(Nos.42475125,42105117,42021004 and 41975143)the National Key R&D Program of China(Nos.2019YFA0607202 and 2020YFA0607501)+4 种基金Jiangsu Science Foundation for Distinguished Young Scholar(No.BK20220055)the 333 Project of Jiangsu Province(No.BRA2017402)the R&D Foundation of Jiangsu Province,China(No.BK20220020)Zhejiang Provincial Basic Public Welfare Research Project(No.LGF22D050004)the Key Laboratory of Ecosystem Carbon Source and Sink,China Meteorological Administration(ECSSCMA).
文摘China is the largest emitter of anthropogenic CO_(2) globally,with its cities recognized as significant emission hotspots.Consequently,evaluating anthropogenic CO_(2) emissions and the carbon neutral capability(CNC)of Chinese cities is critical for climate change mitigation.Despite this importance,no studies to date have assessed recent and future city-scale CNCs using the top-down atmospheric inversion approach,revealing substantial knowledge gaps regarding regional CO_(2) budgets.To address these issues,this research focused on Hangzhou,a megacity known for having the highest forest cover among China’s provincial capitals,as study region.Year-round atmospheric CO_(2) concentration measurements were conducted from December 2020 to November 2021 at two sites:one urban and one suburban.These observations,along with their difference,were utilized to derive city-scale posterior anthropogenic CO_(2) emissions and to evaluate recent and future CNCs.Our key findings are as follows:(1)The manufacturing industry,energy industry and oil refineries/transformation industry were identified as the largest contributors to urban-suburban CO_(2) difference,accounting for 36.5%,21.3%,and 16.6%,respectively.Additionally,82.5%,65.2%,81.2%and 86.3%of total anthropogenic CO_(2) enhancements were attributed to emissions within Hangzhou city in winter,spring,summer and autumn,respectively.(2)The posterior annual anthropogenic CO_(2) emission for Hangzhouwas estimated at 4.65(±0.72)×10^(10) kg/a,indicating significant biases among different prior CO_(2) emission inventories.The annual biological CO_(2) sink,derived from multiple products,was estimated at-0.48(±0.16)×10^(10) kg.(3)The calculated CNC for 2021was 10.3%±3.4%,highlighting a substantial gap towards achieving full carbon neutrality.Considering potential increases in ecosystem carbon sinks due to forest age and uncertainties from climate change,it was predicted that at least 65.2%-82.6%of anthropogenic CO_(2) emissions must be reduced to achieve the goal of full carbon neutrality by year of 2060.
文摘Sweet cherries ( Prunus avium L. cv. Napoleon) were stored in controlled atmospheres (CA) of high O(2) (70% O(2) + 0% CO(2)) or high CO(2) (5% O(2) + 10% CO(2)), in modified atmosphere package (MAP, (13% - 18%) O(2) + (2% -4%) CO(2)) and in air (control) at 1 degreesC to investigate the effects of different O(2) and CO(2) concentrations on physiological properties, quality and storability of the fruits during storage. The results indicated that compared with other treatments, CA with high O(2) concentration decreased fruit decay and ethanol content, but increased the accumulation of malondialdehyde (MDA) and stimulated browning. CA with high CO(2) concentration inhibited polyphenol oxidase (PPO) activity, reduced MDA content, maintained vitamin C content and firmness, decreased fruit decay and browning. Soluble solids contents (SSC) were not significantly affected by different atmosphere treatments. 'Napoleon' fruits stored in 5% O(2) + 10% CO(2) for as long as 80 d were of good quality, but only 40, 20 and 30 d stored in MAP, 70% O(2) + 0% CO(2) and air, re-spectively.
基金Supported by Project of Guizhou Provincial Modernization of Chinese Medicine Material Project(QKHYZ[2011]5049Organization Department of CPCGuizhou Committee(TZJF-2009-02)Promotion Project of Key Scientific and Technological Achievements of Guiyang City([2010]1-T-4)~~
文摘[ Objective ] The paper was to study the effect of controlled atmosphere stress of carbon dioxide （ CO2 ） on Superoxide dismutase （SOD） activity of in- sect, so as to analyze the biological mechanism of the action of controlled atmosphere stress on insect. [ Method] Using nitrotetrazolium blue chloride （NBT） light reduction method, SOD activity of drugstore beetle （ Stegobium panlceum ）, cigarette beetle （ Lasioderma serricorne） and coffee bean beetle （Araecerus fasciculatus） was studied, and the stress response of the enzyme under controlled atmosphere stress of CO2 was analyzed. [ Result ] SOD activity of drugstore beetle, cigarette beetle and coffee bean beetle exposed to controlled atmosphere stress of high concentrations of CO2 for 3 and 6 h had certain degree of increase, and the activity sig- nificantly increased from 2.011±0.954,2.664±0.218 and 1.458±0.718 to 3. 135±0. 105,3.050±0.673 and 2.975±0.229 U/（per pest · 30 min） after treat- ment for 6 h. [ Conclusion] Controlled atmosphere stress of high concentrations of CO2 had certain activation effect on SOD activity of storage pest in Chinese me- dicinal material within the context of sub-lethal events. The results could enrich the insecticidal mechanism of controlled atmosphere and theoretical system of analy- sis on insect resistance to controlled atmosphere.
