[目的]旨在探讨面向碳中和背景下直接空气捕碳(Direct Air Capture,DAC)技术的发展现状、应用案例及其经济性评估,以期为我国实现碳减排目标提供参考。[方法]文章综述了DAC技术的工作原理、类型、运用案例,并分析了其在国内外的发展情...[目的]旨在探讨面向碳中和背景下直接空气捕碳(Direct Air Capture,DAC)技术的发展现状、应用案例及其经济性评估,以期为我国实现碳减排目标提供参考。[方法]文章综述了DAC技术的工作原理、类型、运用案例,并分析了其在国内外的发展情况。通过比较不同研究中的成本数据,评估了DAC技术的经济性,并讨论了当前面临的挑战与可能的解决措施。[结果]研究发现,DAC技术能有效从空气中捕集CO_(2),具有布置灵活、可与可再生能源结合等优点。但其商业化应用仍受到高成本、高能耗和大规模部署的技术挑战的限制。国内外的案例分析揭示DAC技术在实际应用中的效率和成本问题亟待解决,同时也显示了通过技术改进和政策支持可能实现的优化潜力。[结论]尽管存在挑战,DAC技术仍是实现碳中和目标的潜在储备技术,尤其对中国等面临严峻碳减排压力的国家具有重要意义。需要集中研究力量开发更高效、低成本的吸收/吸附剂,改进系统设计,降低能源消耗,并积极探索与可再生能源的结合使用。政府的政策支持和社会的广泛认可也是实现DAC技术商业化的关键因素。通过这些措施可以推动DAC技术的发展和应用,助力实现碳减排和环境保护的双重目标。展开更多
Type I X-ray bursts are the most frequent thermonuclear explosions in nature,resulting from thermonuclear runaway on the surface of an accreting neutron star[1].The breakout reaction 14O(α ,p)17F from the hot CNO cyc...Type I X-ray bursts are the most frequent thermonuclear explosions in nature,resulting from thermonuclear runaway on the surface of an accreting neutron star[1].The breakout reaction 14O(α ,p)17F from the hot CNO cycle may have a prominent impact on the burst light curve and burst ashes[2].However,insufficient experimental information is available to calculate a reliable,precise rate for this reaction[3].We proposed to address the experimental investigation of the 14O(α,p)17F using Time Projection Chamber(TPC)[4].展开更多
The presolar SiC grains[1]carry the original stellar nucleosynthesis signature.Their isotopic anomalies compared to the sun are the strong constrains in the supernovae(SN)model calculations.The 15N-excess in some SiC-...The presolar SiC grains[1]carry the original stellar nucleosynthesis signature.Their isotopic anomalies compared to the sun are the strong constrains in the supernovae(SN)model calculations.The 15N-excess in some SiC-AB grains(12C/13C<10 and 14N/15N<272)is one of the challenges of core-collapse supernovae(CCSNe)models[2].Recently,Pignatari pointed out that the entrainment of H-rich material into the He shell before the SN explosion allows the coproduction of 13C,15N and 26Al,which provides a new production scenario for SiC-AB grains[2].In the He shell nucleosynthesis,the 13C is produced through 12C(p,γ)13N(β+γ)13C reaction.The 14N is synthesized through 13N(n,γ)and 13C(p,γ)reactions.展开更多
Four key reactions, 12C(, )13O, 13C(, n)16O, 25Mg(p, )26Al and 19F(p, )16O, will be studied for the first time within or near the astrophysical relevant energy regions (Gamow window) at Jinping Underground laboratory ...Four key reactions, 12C(, )13O, 13C(, n)16O, 25Mg(p, )26Al and 19F(p, )16O, will be studied for the first time within or near the astrophysical relevant energy regions (Gamow window) at Jinping Underground laboratory for Nuclear Astrophysics (JUNA)[1], which will take the advantage of the ultra-low background of China JinPing underground Laboratory (CJPL), high current accelerator based on ECR source and a highly sensitive detection system.展开更多
Heavy-ion fusion reactions between light nuclei such as carbon and oxygen isotopes have been studied becauseof their importance in a wide variety of stellar burning scenarios. However, due to extremely low cross secti...Heavy-ion fusion reactions between light nuclei such as carbon and oxygen isotopes have been studied becauseof their importance in a wide variety of stellar burning scenarios. However, due to extremely low cross sectionsand signal/background ratio, all the measurements could only be carried out at energies well above the regionof astrophysical interest. The reaction rates in stellar environment could be estimated only by extrapolating theexisted cross sections or the astrophysical S-factors at higher energies. The situation is even more complicated bythe strong, relatively narrow resonances in some reactions, such as 12C+12C, 12C+16O. Traditionally, optical modelor equivalent square-well optical model (ESW) were used to fit the average cross section and predict the reactioncross sections at the energies of astrophysical interest[1]. Recently, a new model, the hindrance model, was proposedto provide systematic fits to fusion reaction data at extreme sub-barrier energies[2]. Lacking of experimental datawithin this energy range, large discrepancies exist among different nuclear reaction models.展开更多
Fusion cross sections with weakly bound nuclei have been a subject of great interest in the last few years[1;2]. Inthis field, the basic question is whether complete fusion (CF) is enhanced or suppressed due to diffus...Fusion cross sections with weakly bound nuclei have been a subject of great interest in the last few years[1;2]. Inthis field, the basic question is whether complete fusion (CF) is enhanced or suppressed due to diffused density andhigh probability of breakup. The answer to this question depends on the energy regime (above or below Coulombbarrier) and on different target mass regions. Therefore, one important approach to investigate this subject is tostudy the systematic behavior of the CF suppression as a function of the target mass or charge.For fusion induced by 9Be, there are some reported works on the CF on different targets, ranging from 89Y to209Bi[2], but the suppression factor of the CF at near barrier energies does not follow a systematic behavior. Forlighter targets, like 27Al and 64Zn [3;4] and for 238U[5], only total fusion (TF) cross sections were measured. Inorder to contribute to the investigation of the fusion of 9Be, we performed experiments to measure complete andincomplete fusion (ICF) of 9Be on the 187Re and 169Tm targets at energies close to the Coulomb barrier.展开更多
The 13C(, n)16O reaction is the key neutron source reaction for the main s-process nucleosynthesis[1]. Theimportant energy range (Gamow window) for the 13C( , n)16O reaction during the s-process spans from 140 to230 k...The 13C(, n)16O reaction is the key neutron source reaction for the main s-process nucleosynthesis[1]. Theimportant energy range (Gamow window) for the 13C( , n)16O reaction during the s-process spans from 140 to230 keV in the center of mass frame. Because of the Coulomb barrier, the cross sections drop exponentially asmeasurement approaches the Gamow window energies. Limited by cosmic ray background and the available beamintensity, the ground-based measurements are limited to energies above 280 keV. Therefore, the extrapolationbased on R-matrix calculation and/or in-direct measurement is the current method to estimate the cross sectionsfor astrophysical interest with limited precision. Moreover, due to the existence of sub-threshold resonances, thereare rather large uncertainties associated with the extrapolated cross sections which limit the precision of the currentreaction rate and thus prevent us from a complete understanding of the nucleosynthesis of heavy elements.展开更多
60Fe is a long-lived nucleus (T1=2=2.62×106 a) which is mainly synthesized in the Carbon-shell burning ofmassive stars. It still could be observed nowadays after being ejected to the space after massive star ends...60Fe is a long-lived nucleus (T1=2=2.62×106 a) which is mainly synthesized in the Carbon-shell burning ofmassive stars. It still could be observed nowadays after being ejected to the space after massive star ends its life assupernova. Along with another long-lived nucleus 26Al (T1=2=7.17×105 a) which is synthesized in the similar stars,the observation of their decay could provide the information of stellar evolution. From 2002-2005 the INTEGRALsatellite with detector obtained 60Fe/26Al flux ratio in our Galaxy to be 0.148(60)[1]. It's significantly smallerthan the theoretical prediction 0.45[2], and indicated that the theory need to be improved to increase the 60Fe yieldor decrease 26Al yield. 60Fe is produced by neutron capture reactions: 58Fe(n, )59Fe and 59Fe(n, )60Fe. Thecompetition between -decay of 59Fe and its neutron capture plays an important role in 60Fe synthesis path. In thepresent work, the impact on the 60Fe synthesis of the -decay process in stellar environment is studied.展开更多
The nuclear shell structure provides an important guide for our understanding of the nuclear structure and the underlying nuclear forces.Following a series of studies on the weakly-bound nuclear region far away the st...The nuclear shell structure provides an important guide for our understanding of the nuclear structure and the underlying nuclear forces.Following a series of studies on the weakly-bound nuclear region far away the stability valley exotic phenomena have been found,such as the emergence of new magic numbers.The study on new magic numbers can provide us a good perspective to understand the evolution of the nuclear shell structure.Recently,the existence of the new proton magic number Z=6 was found in the neutron-rich carbon isotopes^([1]).展开更多
The carbon burning is predicted to be responsible for the phenomenon of X-ray super-burst.Stellar model calculations show that the temperature of neutron star crush is not high enough to trigger ignition^([1]).It has ...The carbon burning is predicted to be responsible for the phenomenon of X-ray super-burst.Stellar model calculations show that the temperature of neutron star crush is not high enough to trigger ignition^([1]).It has been suggested that the fusion reaction between light neutron-rich nuclei may provide an additional source of heat^([2]).展开更多
文摘[目的]旨在探讨面向碳中和背景下直接空气捕碳(Direct Air Capture,DAC)技术的发展现状、应用案例及其经济性评估,以期为我国实现碳减排目标提供参考。[方法]文章综述了DAC技术的工作原理、类型、运用案例,并分析了其在国内外的发展情况。通过比较不同研究中的成本数据,评估了DAC技术的经济性,并讨论了当前面临的挑战与可能的解决措施。[结果]研究发现,DAC技术能有效从空气中捕集CO_(2),具有布置灵活、可与可再生能源结合等优点。但其商业化应用仍受到高成本、高能耗和大规模部署的技术挑战的限制。国内外的案例分析揭示DAC技术在实际应用中的效率和成本问题亟待解决,同时也显示了通过技术改进和政策支持可能实现的优化潜力。[结论]尽管存在挑战,DAC技术仍是实现碳中和目标的潜在储备技术,尤其对中国等面临严峻碳减排压力的国家具有重要意义。需要集中研究力量开发更高效、低成本的吸收/吸附剂,改进系统设计,降低能源消耗,并积极探索与可再生能源的结合使用。政府的政策支持和社会的广泛认可也是实现DAC技术商业化的关键因素。通过这些措施可以推动DAC技术的发展和应用,助力实现碳减排和环境保护的双重目标。
文摘Type I X-ray bursts are the most frequent thermonuclear explosions in nature,resulting from thermonuclear runaway on the surface of an accreting neutron star[1].The breakout reaction 14O(α ,p)17F from the hot CNO cycle may have a prominent impact on the burst light curve and burst ashes[2].However,insufficient experimental information is available to calculate a reliable,precise rate for this reaction[3].We proposed to address the experimental investigation of the 14O(α,p)17F using Time Projection Chamber(TPC)[4].
基金National Key Research and Development program(MOST 2016YFA0400501),National Natural Science Foundation of China(11490564).
文摘The presolar SiC grains[1]carry the original stellar nucleosynthesis signature.Their isotopic anomalies compared to the sun are the strong constrains in the supernovae(SN)model calculations.The 15N-excess in some SiC-AB grains(12C/13C<10 and 14N/15N<272)is one of the challenges of core-collapse supernovae(CCSNe)models[2].Recently,Pignatari pointed out that the entrainment of H-rich material into the He shell before the SN explosion allows the coproduction of 13C,15N and 26Al,which provides a new production scenario for SiC-AB grains[2].In the He shell nucleosynthesis,the 13C is produced through 12C(p,γ)13N(β+γ)13C reaction.The 14N is synthesized through 13N(n,γ)and 13C(p,γ)reactions.
文摘Four key reactions, 12C(, )13O, 13C(, n)16O, 25Mg(p, )26Al and 19F(p, )16O, will be studied for the first time within or near the astrophysical relevant energy regions (Gamow window) at Jinping Underground laboratory for Nuclear Astrophysics (JUNA)[1], which will take the advantage of the ultra-low background of China JinPing underground Laboratory (CJPL), high current accelerator based on ECR source and a highly sensitive detection system.
文摘Heavy-ion fusion reactions between light nuclei such as carbon and oxygen isotopes have been studied becauseof their importance in a wide variety of stellar burning scenarios. However, due to extremely low cross sectionsand signal/background ratio, all the measurements could only be carried out at energies well above the regionof astrophysical interest. The reaction rates in stellar environment could be estimated only by extrapolating theexisted cross sections or the astrophysical S-factors at higher energies. The situation is even more complicated bythe strong, relatively narrow resonances in some reactions, such as 12C+12C, 12C+16O. Traditionally, optical modelor equivalent square-well optical model (ESW) were used to fit the average cross section and predict the reactioncross sections at the energies of astrophysical interest[1]. Recently, a new model, the hindrance model, was proposedto provide systematic fits to fusion reaction data at extreme sub-barrier energies[2]. Lacking of experimental datawithin this energy range, large discrepancies exist among different nuclear reaction models.
文摘Fusion cross sections with weakly bound nuclei have been a subject of great interest in the last few years[1;2]. Inthis field, the basic question is whether complete fusion (CF) is enhanced or suppressed due to diffused density andhigh probability of breakup. The answer to this question depends on the energy regime (above or below Coulombbarrier) and on different target mass regions. Therefore, one important approach to investigate this subject is tostudy the systematic behavior of the CF suppression as a function of the target mass or charge.For fusion induced by 9Be, there are some reported works on the CF on different targets, ranging from 89Y to209Bi[2], but the suppression factor of the CF at near barrier energies does not follow a systematic behavior. Forlighter targets, like 27Al and 64Zn [3;4] and for 238U[5], only total fusion (TF) cross sections were measured. Inorder to contribute to the investigation of the fusion of 9Be, we performed experiments to measure complete andincomplete fusion (ICF) of 9Be on the 187Re and 169Tm targets at energies close to the Coulomb barrier.
文摘The 13C(, n)16O reaction is the key neutron source reaction for the main s-process nucleosynthesis[1]. Theimportant energy range (Gamow window) for the 13C( , n)16O reaction during the s-process spans from 140 to230 keV in the center of mass frame. Because of the Coulomb barrier, the cross sections drop exponentially asmeasurement approaches the Gamow window energies. Limited by cosmic ray background and the available beamintensity, the ground-based measurements are limited to energies above 280 keV. Therefore, the extrapolationbased on R-matrix calculation and/or in-direct measurement is the current method to estimate the cross sectionsfor astrophysical interest with limited precision. Moreover, due to the existence of sub-threshold resonances, thereare rather large uncertainties associated with the extrapolated cross sections which limit the precision of the currentreaction rate and thus prevent us from a complete understanding of the nucleosynthesis of heavy elements.
文摘60Fe is a long-lived nucleus (T1=2=2.62×106 a) which is mainly synthesized in the Carbon-shell burning ofmassive stars. It still could be observed nowadays after being ejected to the space after massive star ends its life assupernova. Along with another long-lived nucleus 26Al (T1=2=7.17×105 a) which is synthesized in the similar stars,the observation of their decay could provide the information of stellar evolution. From 2002-2005 the INTEGRALsatellite with detector obtained 60Fe/26Al flux ratio in our Galaxy to be 0.148(60)[1]. It's significantly smallerthan the theoretical prediction 0.45[2], and indicated that the theory need to be improved to increase the 60Fe yieldor decrease 26Al yield. 60Fe is produced by neutron capture reactions: 58Fe(n, )59Fe and 59Fe(n, )60Fe. Thecompetition between -decay of 59Fe and its neutron capture plays an important role in 60Fe synthesis path. In thepresent work, the impact on the 60Fe synthesis of the -decay process in stellar environment is studied.
基金National Key Research and Development Program of China(2016YFA0400501)Strategic Priority Research Program of Chinese Academy of Sciences(XDB34020200)National Natural Science Foundation of China(E211263GJ0)。
文摘The nuclear shell structure provides an important guide for our understanding of the nuclear structure and the underlying nuclear forces.Following a series of studies on the weakly-bound nuclear region far away the stability valley exotic phenomena have been found,such as the emergence of new magic numbers.The study on new magic numbers can provide us a good perspective to understand the evolution of the nuclear shell structure.Recently,the existence of the new proton magic number Z=6 was found in the neutron-rich carbon isotopes^([1]).
文摘The carbon burning is predicted to be responsible for the phenomenon of X-ray super-burst.Stellar model calculations show that the temperature of neutron star crush is not high enough to trigger ignition^([1]).It has been suggested that the fusion reaction between light neutron-rich nuclei may provide an additional source of heat^([2]).
