Where sustainable development is concerned, there is an urgent need to establish new information systems that integrate economic, social and ecological factors. The emergence of demand for this information makes the d...Where sustainable development is concerned, there is an urgent need to establish new information systems that integrate economic, social and ecological factors. The emergence of demand for this information makes the development of ecological accounting possible. Yet, most current research on ecological accounting focuses on two aspects: (1) the theoretical aspect, including background, concepts and models and (2) specific research on ecological accounting. Some scholars have proposed a conceptual framework, but this is not systematic or thorough enough. Seizing the opportunity of sustainable development in a key strategic location of the world, this paper begins by analyzing the logical evolution of ecological accounting, summarizes the existing ecological accounting theory, and combines the mature theoretical study of resources accounting with environmental accounting. All of these efforts result in this paper forwarding a framework of ecological accounting that aims to provide a guideline for future development.展开更多
During the EAST radiative divertor experiments,one of the key challenges was how to avoid the occurrence of disruptive events caused by excessive impurity seeding.To estimate the required impurity fraction for diverto...During the EAST radiative divertor experiments,one of the key challenges was how to avoid the occurrence of disruptive events caused by excessive impurity seeding.To estimate the required impurity fraction for divertor detachment,we introduce a reduced edge plasma radiation model.In the model,based on the momentum conservation along the magnetic field line,the upstream pressure is determined by the plasma density and temperature at the divertor target,and then the impurity radiation loss is obtained by the balance of the heat and particle fluxes.It is found that the required impurity fraction shows a non-monotonic variation with divertor electron temperature(T_(d))when 0.1 eV<T_(d)<10 eV.In the range of 0.1 eV<T_(d)<1 e V,the position near the valley of required impurity fraction corresponds to strong plasma recombination.Due to the dependence of the volumetric momentum loss effect on the T_(d)in the range of 1 eV<T_(d)<10 eV,the required impurity fraction peaks and then decreases as T_(d)is increased.Compared to neon,the usage of argon reduces the impurity fraction by about twice.In addition,for the various fitting parameters in the pressure-momentum loss model,it is shown that the tendency of required impurity fraction with T_(d)always increases first and then decreases in the range of 1 eV<T_(d)<10 eV,but the required impurity fraction decreases when the model that characterizes the strong loss in pressure momentum is used.展开更多
During ion cyclotron resonance heating,the sheath power dissipation caused by ion acceleration in the radio frequency(RF)sheath is one of the main causes of RF power loss in the tokamak edge region.To estimate the pow...During ion cyclotron resonance heating,the sheath power dissipation caused by ion acceleration in the radio frequency(RF)sheath is one of the main causes of RF power loss in the tokamak edge region.To estimate the power dissipation of an RF sheath in the ion cyclotron range of frequency(ICRF),a 1 D fluid model for the multi-component plasma sheath driven by a sinusoidal disturbance current in the ICRF is presented.By investigation of the sheath potential and ion flux at the wall,it is shown that the larger frequency and lower amplitude of the disturbance current can cause smaller sheath power dissipation.The effect of the energetic ion on the sheath power dissipation depends on the disturbance current.For large amplitude of disturbance current,the increase in the concentration and energy of the energetic ion leads to a decrease in sheath power dissipation.While for a small disturbance current,the sheath power dissipation demonstrates non-monotonic variation with the concentration and energy of the energetic ion.In addition,the sheath power dissipation is found to have a small increase in the presence of light impurity ions with low valence.展开更多
During edge localized modes(ELMs), the sheath evolution in front of the Experimental Advanced Superconducting Tokamak(EAST) upper divertor is studied to estimate the sputtered tungsten(W) atoms from the divertor targe...During edge localized modes(ELMs), the sheath evolution in front of the Experimental Advanced Superconducting Tokamak(EAST) upper divertor is studied to estimate the sputtered tungsten(W) atoms from the divertor target. A large potential drop across the sheath is formed during ELMs by compared with inter-ELMs, and the maximum of sheath potential drop can exceed one thousand of e V in current EAST operation. Due to the enhancement of the sheath potential drop during ELMs, the W physical sputtering yield from the deuterium(D) ions and the impurity ions on the upper divertor target is found to be significant. It is established that the sputtered W yield during ELMs is at least higher by an order of magnitude than inter-ELMs, and D ions and carbon(C) ions are the main ions governing the W production for the current H-mode with ELMs discharges. With increase in the pedestal electron temperature, the maximum of the D and C ion impact energy during ELMs shows a nearly linear increase, and the D ions have sufficient impact energy to cause the strong W physical sputtering. As a consequence, the D ions may dominate the sputtered W flux from the divertor target when the C concentration is controlled less than one percent for the higher heating power H-mode with ELM discharges in near future.展开更多
Covalent organic frameworks(COFs)have numerous advantages,including high specific surface area,good stability,and ease of modification.These features have generated significant interest in utilizing COFs as chromatogr...Covalent organic frameworks(COFs)have numerous advantages,including high specific surface area,good stability,and ease of modification.These features have generated significant interest in utilizing COFs as chromatographic stationary phase materials.Herein,two monomers,1,3,5-tris-(4-aminophenyl)triazine(TAPT)and 1,3,5-benzenetricarboxaldehyde,are selected to construct the COF material.A novel core-shell type composite material named SiO_(2)@COF was prepared with the covalent triazine framework layer grafted on the silica by in situ growth method,and then the C18 chain was post-modifi ed on the SiO_(2)@COF material,named SiO_(2)@COF-C18.Multiple methods have been employed to illustrate the morphological and structural characteristics of the SiO_(2)@COF-C18 material.Then,several analytes,including anilines,polycyclic aromatic hydrocarbons(PAHs),alkylbenzenes,and positional isomers,were selected to study the separation mechanism of the SiO_(2)@COF-C18 column,which demonstrated that these analytes were separated on the SiO_(2)@COF-C18 column under chromatographic modes of hydrophobic interaction,π-πinteraction,steric hindrance eff ect,etc.The prepared chromatographic column had excellent repeatability and high separation efficiency,and it was used to determine acetaminophen tablets under reversed-phase conditions.These results open a new avenue for the post-modification of hydrophobic groups on COF materials for pharmaceutical analysis.展开更多
At present,the research on circular economy has made a lot of substantive results both at home and abroad.But for the papermaking enterprise,which is the representative of the light industry,few studies have analyzed ...At present,the research on circular economy has made a lot of substantive results both at home and abroad.But for the papermaking enterprise,which is the representative of the light industry,few studies have analyzed the evaluation index system of circular economy.Since the current material flow analyses have limitations that the researchers cannot calculate materials with different units.The authors take advantage of the intrinsic correlation between the basic principle of value flow analysis and circular economy,and then analyze the dynamic changes of material flow and value flow through enterprises internal production process.Considering the resource output,the authors set up the layered structure of the evaluation index system,and then preliminarily determine the index form.Next,the authors use the frequency statistics analysis method to adjust indicators,forming a preliminary index system.After that,the principal component analysis and independent analysis are applied for screening.Finally,the authors build a circular economy evaluation index system for papermaking enterprise to provide scientific guidance for the process of circular economy.展开更多
文摘Where sustainable development is concerned, there is an urgent need to establish new information systems that integrate economic, social and ecological factors. The emergence of demand for this information makes the development of ecological accounting possible. Yet, most current research on ecological accounting focuses on two aspects: (1) the theoretical aspect, including background, concepts and models and (2) specific research on ecological accounting. Some scholars have proposed a conceptual framework, but this is not systematic or thorough enough. Seizing the opportunity of sustainable development in a key strategic location of the world, this paper begins by analyzing the logical evolution of ecological accounting, summarizes the existing ecological accounting theory, and combines the mature theoretical study of resources accounting with environmental accounting. All of these efforts result in this paper forwarding a framework of ecological accounting that aims to provide a guideline for future development.
基金supported by National Natural Science Foundation of China(No.12375227)Innovation in Fusion Engineering Technology of Institute(No.E35QT1080C)。
文摘During the EAST radiative divertor experiments,one of the key challenges was how to avoid the occurrence of disruptive events caused by excessive impurity seeding.To estimate the required impurity fraction for divertor detachment,we introduce a reduced edge plasma radiation model.In the model,based on the momentum conservation along the magnetic field line,the upstream pressure is determined by the plasma density and temperature at the divertor target,and then the impurity radiation loss is obtained by the balance of the heat and particle fluxes.It is found that the required impurity fraction shows a non-monotonic variation with divertor electron temperature(T_(d))when 0.1 eV<T_(d)<10 eV.In the range of 0.1 eV<T_(d)<1 e V,the position near the valley of required impurity fraction corresponds to strong plasma recombination.Due to the dependence of the volumetric momentum loss effect on the T_(d)in the range of 1 eV<T_(d)<10 eV,the required impurity fraction peaks and then decreases as T_(d)is increased.Compared to neon,the usage of argon reduces the impurity fraction by about twice.In addition,for the various fitting parameters in the pressure-momentum loss model,it is shown that the tendency of required impurity fraction with T_(d)always increases first and then decreases in the range of 1 eV<T_(d)<10 eV,but the required impurity fraction decreases when the model that characterizes the strong loss in pressure momentum is used.
基金supported by National Natural Science Foundation of China(Grant No.11775257)。
文摘During ion cyclotron resonance heating,the sheath power dissipation caused by ion acceleration in the radio frequency(RF)sheath is one of the main causes of RF power loss in the tokamak edge region.To estimate the power dissipation of an RF sheath in the ion cyclotron range of frequency(ICRF),a 1 D fluid model for the multi-component plasma sheath driven by a sinusoidal disturbance current in the ICRF is presented.By investigation of the sheath potential and ion flux at the wall,it is shown that the larger frequency and lower amplitude of the disturbance current can cause smaller sheath power dissipation.The effect of the energetic ion on the sheath power dissipation depends on the disturbance current.For large amplitude of disturbance current,the increase in the concentration and energy of the energetic ion leads to a decrease in sheath power dissipation.While for a small disturbance current,the sheath power dissipation demonstrates non-monotonic variation with the concentration and energy of the energetic ion.In addition,the sheath power dissipation is found to have a small increase in the presence of light impurity ions with low valence.
基金Project supported by the National Key R&D Program of China(Grant Nos.2017YFE0300400 and 2017YFE0301300)the National Natural Science Foundation of China(Grant Nos.11475223 and 11775257)+1 种基金the National Magnetic Confinement Fusion Science Program of China(Grant No.2015GB101003)partly supported by AHNSF of China(Grant No.1808085J07)
文摘During edge localized modes(ELMs), the sheath evolution in front of the Experimental Advanced Superconducting Tokamak(EAST) upper divertor is studied to estimate the sputtered tungsten(W) atoms from the divertor target. A large potential drop across the sheath is formed during ELMs by compared with inter-ELMs, and the maximum of sheath potential drop can exceed one thousand of e V in current EAST operation. Due to the enhancement of the sheath potential drop during ELMs, the W physical sputtering yield from the deuterium(D) ions and the impurity ions on the upper divertor target is found to be significant. It is established that the sputtered W yield during ELMs is at least higher by an order of magnitude than inter-ELMs, and D ions and carbon(C) ions are the main ions governing the W production for the current H-mode with ELMs discharges. With increase in the pedestal electron temperature, the maximum of the D and C ion impact energy during ELMs shows a nearly linear increase, and the D ions have sufficient impact energy to cause the strong W physical sputtering. As a consequence, the D ions may dominate the sputtered W flux from the divertor target when the C concentration is controlled less than one percent for the higher heating power H-mode with ELM discharges in near future.
基金the Project of Sichuan Department of Science and Technology(2022NSFSC0622)the Scientifi c Research Project of Southwest Medical University(2021ZKMS043)+1 种基金the Science and Technology Project of Luzhou(2021-JYJ-74)the National Natural Science Foundation of China(21974015)。
文摘Covalent organic frameworks(COFs)have numerous advantages,including high specific surface area,good stability,and ease of modification.These features have generated significant interest in utilizing COFs as chromatographic stationary phase materials.Herein,two monomers,1,3,5-tris-(4-aminophenyl)triazine(TAPT)and 1,3,5-benzenetricarboxaldehyde,are selected to construct the COF material.A novel core-shell type composite material named SiO_(2)@COF was prepared with the covalent triazine framework layer grafted on the silica by in situ growth method,and then the C18 chain was post-modifi ed on the SiO_(2)@COF material,named SiO_(2)@COF-C18.Multiple methods have been employed to illustrate the morphological and structural characteristics of the SiO_(2)@COF-C18 material.Then,several analytes,including anilines,polycyclic aromatic hydrocarbons(PAHs),alkylbenzenes,and positional isomers,were selected to study the separation mechanism of the SiO_(2)@COF-C18 column,which demonstrated that these analytes were separated on the SiO_(2)@COF-C18 column under chromatographic modes of hydrophobic interaction,π-πinteraction,steric hindrance eff ect,etc.The prepared chromatographic column had excellent repeatability and high separation efficiency,and it was used to determine acetaminophen tablets under reversed-phase conditions.These results open a new avenue for the post-modification of hydrophobic groups on COF materials for pharmaceutical analysis.
基金supported by the National Natural Science Foundation of China (Grant No.71303263)the State Key Program of National Natural Science Foundation of China (Grant No.71431006)+6 种基金the Key Projects of Philosophy and Social Sciences of the Ministry of Education of China (Grant No.13JZD016)the Major Program of the National Social Science Foundation of China (Grant No.11&ZD166)the Humanities and Social Sciences Program Foundation of the Ministry of Education of China (Grant No.11YJC790312)the Doctoral Foundation of the Ministry of Education of China (Grant No.20130162120045)the Energysaving and Emission Reduction Demonstration Project of Changsha City (Grant No.CSCG-HNSZ-DY20131002,Procurement of [2013D] 0012-1 Changsha Finance)the Social Sciences Program Foundation of Hunan Province (Grant No.13YBA353)the Soft Science Program of Hunan Province (Grant No.2014ZK3124)
文摘At present,the research on circular economy has made a lot of substantive results both at home and abroad.But for the papermaking enterprise,which is the representative of the light industry,few studies have analyzed the evaluation index system of circular economy.Since the current material flow analyses have limitations that the researchers cannot calculate materials with different units.The authors take advantage of the intrinsic correlation between the basic principle of value flow analysis and circular economy,and then analyze the dynamic changes of material flow and value flow through enterprises internal production process.Considering the resource output,the authors set up the layered structure of the evaluation index system,and then preliminarily determine the index form.Next,the authors use the frequency statistics analysis method to adjust indicators,forming a preliminary index system.After that,the principal component analysis and independent analysis are applied for screening.Finally,the authors build a circular economy evaluation index system for papermaking enterprise to provide scientific guidance for the process of circular economy.
