Regional CO_(2) emissions are closely related to their territorial function, which is the major role a region plays in sustainable processes on the earth's surface. Given that China is implementing a top-down emis...Regional CO_(2) emissions are closely related to their territorial function, which is the major role a region plays in sustainable processes on the earth's surface. Given that China is implementing a top-down emission allocation quota strategy, studying the impact of a territorial function on emissions addresses the research gap from a spatial integration dimension.By investigating the effects of three basic functional territories(urbanization zones(UZ), food security zones(FSZ), and ecological security zones(ESZ)), horizontal spatial structure and vertical combinations of functional territories on CO_(2) emission patterns in China, we found that functional territory patterns were highly coupled with the spatial distribution of CO_(2) emissions, with a ratio of CO_(2) emissions from UZ–FSZ–ESZ was stable at around 5:2:1 from 2000 to 2017. Spatially, CO_(2) emissions in FSZ and ESZ were 1.06–2.12 times higher than the average value within 200 km from the UZ. As territorial function combination increased with spatial upscaling, the emission characteristics attributable to functional territories became indistinct. The findings above can provide a basis for the long-term prediction of CO_(2) emissions from spatial dimension, support scientific guidance for inter-zone cooperation and classified management of carbon emissions with the major function oriented zones as impetus.展开更多
Monitoring of potential bearing faults in operation is of critical importance to safe operation of high speed trains.One of the major challenges is how to differentiate relevant signals to operational conditions of be...Monitoring of potential bearing faults in operation is of critical importance to safe operation of high speed trains.One of the major challenges is how to differentiate relevant signals to operational conditions of bearings from noises emitted from the surrounding environment.In this work,we report a procedure for analyzing acoustic emission signals collected from rolling bearings for diagnosis of bearing health conditions by examining their morphological pattern spectrum(MPS) through a multi-scale morphology analysis procedure.The results show that acoustic emission signals resulted from a given type of bearing faults share rather similar MPS curves.Further examinations in terms of sample entropy and Lempel-Ziv complexity of MPS curves suggest that these two parameters can be utilized to determine damage modes.展开更多
A discharge ignited by an AC power source in contact with deionized water as one of the electrodes is investigated.Immediately after initiation,the discharge exhibits a unique phenomenon:the gas-phase discharge is ext...A discharge ignited by an AC power source in contact with deionized water as one of the electrodes is investigated.Immediately after initiation,the discharge exhibits a unique phenomenon:the gas-phase discharge is extended into the liquid.Later,a cone-like structure is observed at the liquid surface.Synchronous monitoring of current–voltage characteristics and liquid properties versus time suggests that the discharge shapes are functions of the liquid properties.The spatio-temporal profiles indicate the potential effects of water,ambient air impurities,and metastable argon on the discharge chemistry.This becomes more obvious near the liquid surface due to increasing production of various transient reactive species such as centerdot OH and NO centerdot.Moreover,it is revealed that thermalization of the rotational population distributions of the rotational states(N′⩽6,J′⩽13/2)in the Q1 branch of the OH(A2Σ+,υ′=0→X2Π3/2,υ′′=0)band ro-vibrational system is influenced by the humid environment near the liquid surface.In addition,the transient behaviors of instantaneous concentrations of long-lived reactive species(LRS)such as H2O2,NO−2,and NO−3 are observed with lengthening the discharge time.The production of multiple transient and LRS proposes AC excited gas–liquid argon discharge as a potential applicant in industrial wastewater cleaning,clinical medicine,and agriculture.展开更多
China has large regional disparities in carbon dioxide CO_(2) emissions with economic development among its 31 provincial mainland regions.This paper investigates these disparities in CO_(2) emission patterns and iden...China has large regional disparities in carbon dioxide CO_(2) emissions with economic development among its 31 provincial mainland regions.This paper investigates these disparities in CO_(2) emission patterns and identifies the factors underlying the differences.Results show that the 30 study China's mainland provinces(Tibet not included)can be divided into seven groups with three typical CO_(2) emission patterns.Index decomposition results indicate that changes in economic development,the industrial sector,and technology contribute far more to increased CO_(2) emissions than do population,energy structure,and other sectors.Close inspection reveals that different industry structures and technology contribute greatly to the differences observed in CO_(2) emissions between provinces with similar economic output.This study highlights the importance of region-specific industrial structure adjustment policies,especially for regions transitioning to heavy industry and for those still in the primary stages of industrialization.The potential application of a domestic carbon emissions trading system,to encourage regional investment in updated technology,is also discussed.展开更多
In this paper, we demonstrate that for colloidal CdSe/CdS nanoplatelets, a rectangular shape induces emission asymmetry, in terms of both polarization and emission patterns. Polarimetry and emission pattern analyses a...In this paper, we demonstrate that for colloidal CdSe/CdS nanoplatelets, a rectangular shape induces emission asymmetry, in terms of both polarization and emission patterns. Polarimetry and emission pattern analyses are combined to provide information on the orientation of the transition dipoles involved in the nanoplatelet emission. It is shown that for rectangular nanoplatelets, the emission is polarized and the emission patterns are anisotropic, whereas they remain nonpolarized and isotropic for square nanoplatelets. This can be appropriately described by the dielectric antenna effect induced by the elongated shape of the rectangular platelet.展开更多
基金National Natural Science Foundation of China,No.42230510。
文摘Regional CO_(2) emissions are closely related to their territorial function, which is the major role a region plays in sustainable processes on the earth's surface. Given that China is implementing a top-down emission allocation quota strategy, studying the impact of a territorial function on emissions addresses the research gap from a spatial integration dimension.By investigating the effects of three basic functional territories(urbanization zones(UZ), food security zones(FSZ), and ecological security zones(ESZ)), horizontal spatial structure and vertical combinations of functional territories on CO_(2) emission patterns in China, we found that functional territory patterns were highly coupled with the spatial distribution of CO_(2) emissions, with a ratio of CO_(2) emissions from UZ–FSZ–ESZ was stable at around 5:2:1 from 2000 to 2017. Spatially, CO_(2) emissions in FSZ and ESZ were 1.06–2.12 times higher than the average value within 200 km from the UZ. As territorial function combination increased with spatial upscaling, the emission characteristics attributable to functional territories became indistinct. The findings above can provide a basis for the long-term prediction of CO_(2) emissions from spatial dimension, support scientific guidance for inter-zone cooperation and classified management of carbon emissions with the major function oriented zones as impetus.
基金supported by the National Natural Science Foundation of China (Grant 51205017)the National Science and Technology Support Program (Grant 2015BAG12B01)the National Basic Research Program of China (Grant 2015CB654805)
文摘Monitoring of potential bearing faults in operation is of critical importance to safe operation of high speed trains.One of the major challenges is how to differentiate relevant signals to operational conditions of bearings from noises emitted from the surrounding environment.In this work,we report a procedure for analyzing acoustic emission signals collected from rolling bearings for diagnosis of bearing health conditions by examining their morphological pattern spectrum(MPS) through a multi-scale morphology analysis procedure.The results show that acoustic emission signals resulted from a given type of bearing faults share rather similar MPS curves.Further examinations in terms of sample entropy and Lempel-Ziv complexity of MPS curves suggest that these two parameters can be utilized to determine damage modes.
基金by National Natural Science Foundation of China(No.51578309)。
文摘A discharge ignited by an AC power source in contact with deionized water as one of the electrodes is investigated.Immediately after initiation,the discharge exhibits a unique phenomenon:the gas-phase discharge is extended into the liquid.Later,a cone-like structure is observed at the liquid surface.Synchronous monitoring of current–voltage characteristics and liquid properties versus time suggests that the discharge shapes are functions of the liquid properties.The spatio-temporal profiles indicate the potential effects of water,ambient air impurities,and metastable argon on the discharge chemistry.This becomes more obvious near the liquid surface due to increasing production of various transient reactive species such as centerdot OH and NO centerdot.Moreover,it is revealed that thermalization of the rotational population distributions of the rotational states(N′⩽6,J′⩽13/2)in the Q1 branch of the OH(A2Σ+,υ′=0→X2Π3/2,υ′′=0)band ro-vibrational system is influenced by the humid environment near the liquid surface.In addition,the transient behaviors of instantaneous concentrations of long-lived reactive species(LRS)such as H2O2,NO−2,and NO−3 are observed with lengthening the discharge time.The production of multiple transient and LRS proposes AC excited gas–liquid argon discharge as a potential applicant in industrial wastewater cleaning,clinical medicine,and agriculture.
基金This research was supported by the Environment Research and Technology development Fund(S-6,E-0806)of the Ministry of the Environment,KAKENHI(21612005,20330050)Japan and the Nagoya University Global COE(Center of Excellence)Program“From Earth System Science to Basic and Clinical Environmental Studies”(GCOE-BCES)of the Ministry of Education,Culture,Sports,Science and Technology(MEXT)of Japan.
文摘China has large regional disparities in carbon dioxide CO_(2) emissions with economic development among its 31 provincial mainland regions.This paper investigates these disparities in CO_(2) emission patterns and identifies the factors underlying the differences.Results show that the 30 study China's mainland provinces(Tibet not included)can be divided into seven groups with three typical CO_(2) emission patterns.Index decomposition results indicate that changes in economic development,the industrial sector,and technology contribute far more to increased CO_(2) emissions than do population,energy structure,and other sectors.Close inspection reveals that different industry structures and technology contribute greatly to the differences observed in CO_(2) emissions between provinces with similar economic output.This study highlights the importance of region-specific industrial structure adjustment policies,especially for regions transitioning to heavy industry and for those still in the primary stages of industrialization.The potential application of a domestic carbon emissions trading system,to encourage regional investment in updated technology,is also discussed.
文摘In this paper, we demonstrate that for colloidal CdSe/CdS nanoplatelets, a rectangular shape induces emission asymmetry, in terms of both polarization and emission patterns. Polarimetry and emission pattern analyses are combined to provide information on the orientation of the transition dipoles involved in the nanoplatelet emission. It is shown that for rectangular nanoplatelets, the emission is polarized and the emission patterns are anisotropic, whereas they remain nonpolarized and isotropic for square nanoplatelets. This can be appropriately described by the dielectric antenna effect induced by the elongated shape of the rectangular platelet.