This paper constructs coefficients of the integral and the internal structure upgrading in the secondary and tertiary industries, selects per capita real gross domestic product as a threshold variable and build panel ...This paper constructs coefficients of the integral and the internal structure upgrading in the secondary and tertiary industries, selects per capita real gross domestic product as a threshold variable and build panel threshold model according to inter-provincial panel data of China from 1998 to 2016. Results indicated that population aging has a double threshold effect on the integral industrial structure upgrading, whose influence increases first and then decreases, significantly promoting the upgrading process. As for internal structure, population aging has no significant threshold effect on the upgrading in the secondary industry, but exerts a single negative threshold effect in the tertiary industry. When economic development is under the threshold, its negative impact is greater. Further analysis also suggests that regional differences exist significantly in the threshold effect of population aging on the industrial structure upgrading.展开更多
This paper aims to discuss and analyze the distribution characteristics of the private placement among different regions and different industries by state-owned and private holding enterprises as well as the changed e...This paper aims to discuss and analyze the distribution characteristics of the private placement among different regions and different industries by state-owned and private holding enterprises as well as the changed earning capacities of the capital before and after the placement. Taking the private placement financing data of the listed companies during the period of 2006-2011 in China's A-share markets as the sample, this study adopts the panel data model to conduct a quantitative analysis of the industrial upgrading effect of the private placement by listed companies with different holding natures. The empirical results show that though the private placement by the state-owned and private holding enterprises has not significantly improved the Clark index in any region, the private placement by private holding companies has significantly improved the growth rate of the tertiary industry in the eastern region. While reducing the proportion of the tertiary industry in GDP in the central and western regions, it has also improved the growth rate of the secondary industry and its proportion in GDP in that region to a larger extent. Yet the private placement of state-owned enterprises has no significant effect on the industrial upgrading path in any region except that it helped to raise the proportion of the secondary industry in GDP a little in the eastern region.展开更多
Recycling graphite anode from spent lithium-ion batteries(SLIBs)is regarded as a crucial approach to promoting sustainable energy storage industry.However,the recycled graphite(RG)generally presents degraded structure...Recycling graphite anode from spent lithium-ion batteries(SLIBs)is regarded as a crucial approach to promoting sustainable energy storage industry.However,the recycled graphite(RG)generally presents degraded structure and performance.Herein,the residual fluoride self-activated effect is proposed for the upgraded utilization of RG.Simple and low-energy water immersion treatment not only widens the interlayer spacing,but also retains appropriate fluoride on the surface of RG.Theoretical analysis and experiments demonstrate that the residual fluoride can optimize Li~+migration and deposition kinetics,resulting in better Li~+intercalation/deintercalation in the interlayer and more stable Li metal plating/stripping on the surface of RG,As a result,the designed LFP||RG full cells achieve ultrahigh reversibility(~100%Coulombic efficiency),high capacity retention(67%after 200 cycles,0.85 N/P ratio),and commendable adaptability(stable cycling without short-circuiting,0.15 N/P ratio).The energy density is improved from 334 Wh kg^(-1)of 1.1 N/P ratio to 367 Wh kg^(-1)of 0.85 N/P ratio(total mass based on cathode and anode).The exploration of RG by residual fluoride self-activated effect achieves upgraded utilization beyond fresh commercial graphite and highlights a new strategy for efficient reuse of SLIBs.展开更多
Pore structure characteristics are significant factor in the evaluation of the physical characteristics of low-rank coal.In this study,three low-rank coal samples were collected from the Xishanyao Formation,Santanghu ...Pore structure characteristics are significant factor in the evaluation of the physical characteristics of low-rank coal.In this study,three low-rank coal samples were collected from the Xishanyao Formation,Santanghu Basin,and low-temperature liquid-nitrogen adsorption(LP-N2A)measurements were taken under various pretreatment temperatures.Owing to the continuous loss of water and volatile matter in low-rank coal,the total pore volume assumes a three-step profile with knee temperatures of 150°C and 240°C.However,the ash in the coal can protect the coal skeleton.Pore collapse mainly occurs for mesopores with aperture smaller than 20 nm.Mesopores with apertures smaller than 5 nm exhibit a continuous decrease in pore volume,whereas the pore volume of mesopores with apertures ranging from 5 to 10 nm increases at lower pretreatment temperatures(<150°C)followed by a faint decrease.As for mesopores with apertures larger than 10 nm,the pore volume increases significantly when the pretreatment temperature reaches 300°C.The pore structure of low-rank coal features a significant heating effect,the pretreatment temperature should not exceed 150°C when the LP-N2A is used to evaluate the pore structure of low-rank coal to effectively evaluate the reservoir characteristics of low-rank coal.展开更多
Based on panel data from 16 cities in Shandong Province from 2013 to 2022,and grounded in theoretical analysis,this paper constructs a benchmark regression model,a mediating effect model,and a heterogeneity test for e...Based on panel data from 16 cities in Shandong Province from 2013 to 2022,and grounded in theoretical analysis,this paper constructs a benchmark regression model,a mediating effect model,and a heterogeneity test for empirical analysis.The results show that:(1)the digital economy has a significant positive effect on promoting the transformation and upgrading of the manufacturing industry in Shandong Province;(2)the digital economy can drive the transformation and upgrading of the manufacturing industry through technological innovation;and(3)the impact of the digital economy on the transformation and upgrading of the manufacturing industry in Shandong Province is evidently heterogeneous.展开更多
Based on the provincial data of tourism and cultural industries from 2009 to 2019,this paper studies the impact of the integration of culture and tourism on the economic benefits of regional tourism in China.The resul...Based on the provincial data of tourism and cultural industries from 2009 to 2019,this paper studies the impact of the integration of culture and tourism on the economic benefits of regional tourism in China.The results show that:①The integration level of the two industries is generally low in all provinces and regions,and the regional differences are obvious.The integration degree of the central and eastern regions is generally higher than that of the western regions.②The integration degree of culture and tourism has a significant positive impact on the economic benefits of regional tourism.The influence on the central and eastern regions is greater than that on the western regions.③The level of informatization has a positive moderating effect on the economic benefits of regional tourism caused by the integration of culture and tourism.④Government intervention has a negative moderating effect on the economic benefits of tourism.In addition,the level of regional economic development,accessibility and tourism resource endowment are also significant factors affecting the economic benefits of regional tourism.The results show that promoting the deep integration of culture and tourism,promoting the informatization of tourism and moderate government intervention in the industry are conducive to improving the economic benefits of regional tourism.展开更多
基金This study is supported by funds of National Natural Science Foundation of China’s project “China’s population aging process and labor productivity: inspection, forecasting and policy options”[Grant number: 71573093]National Natural Science Foundation of China’s project [Grant number:71573093].
文摘This paper constructs coefficients of the integral and the internal structure upgrading in the secondary and tertiary industries, selects per capita real gross domestic product as a threshold variable and build panel threshold model according to inter-provincial panel data of China from 1998 to 2016. Results indicated that population aging has a double threshold effect on the integral industrial structure upgrading, whose influence increases first and then decreases, significantly promoting the upgrading process. As for internal structure, population aging has no significant threshold effect on the upgrading in the secondary industry, but exerts a single negative threshold effect in the tertiary industry. When economic development is under the threshold, its negative impact is greater. Further analysis also suggests that regional differences exist significantly in the threshold effect of population aging on the industrial structure upgrading.
文摘This paper aims to discuss and analyze the distribution characteristics of the private placement among different regions and different industries by state-owned and private holding enterprises as well as the changed earning capacities of the capital before and after the placement. Taking the private placement financing data of the listed companies during the period of 2006-2011 in China's A-share markets as the sample, this study adopts the panel data model to conduct a quantitative analysis of the industrial upgrading effect of the private placement by listed companies with different holding natures. The empirical results show that though the private placement by the state-owned and private holding enterprises has not significantly improved the Clark index in any region, the private placement by private holding companies has significantly improved the growth rate of the tertiary industry in the eastern region. While reducing the proportion of the tertiary industry in GDP in the central and western regions, it has also improved the growth rate of the secondary industry and its proportion in GDP in that region to a larger extent. Yet the private placement of state-owned enterprises has no significant effect on the industrial upgrading path in any region except that it helped to raise the proportion of the secondary industry in GDP a little in the eastern region.
基金the National Natural Science Foundation of China(21975212)the Industry Leading Key Projects of Fujian Province(2022H0057)the High-level talent start-up Foundation of Xiamen Institute of Technology for financial support。
文摘Recycling graphite anode from spent lithium-ion batteries(SLIBs)is regarded as a crucial approach to promoting sustainable energy storage industry.However,the recycled graphite(RG)generally presents degraded structure and performance.Herein,the residual fluoride self-activated effect is proposed for the upgraded utilization of RG.Simple and low-energy water immersion treatment not only widens the interlayer spacing,but also retains appropriate fluoride on the surface of RG.Theoretical analysis and experiments demonstrate that the residual fluoride can optimize Li~+migration and deposition kinetics,resulting in better Li~+intercalation/deintercalation in the interlayer and more stable Li metal plating/stripping on the surface of RG,As a result,the designed LFP||RG full cells achieve ultrahigh reversibility(~100%Coulombic efficiency),high capacity retention(67%after 200 cycles,0.85 N/P ratio),and commendable adaptability(stable cycling without short-circuiting,0.15 N/P ratio).The energy density is improved from 334 Wh kg^(-1)of 1.1 N/P ratio to 367 Wh kg^(-1)of 0.85 N/P ratio(total mass based on cathode and anode).The exploration of RG by residual fluoride self-activated effect achieves upgraded utilization beyond fresh commercial graphite and highlights a new strategy for efficient reuse of SLIBs.
基金This work was supported by the Natural Science Basic Research Plan in Shaanxi Province of China(Program No.2019JQ-527)Shandong Key laboratory of Depositional Mineralization and Sedimentary Mineral Open Fund(Program No.DMSM20190014)Scientific Research Program Funded by Shaanxi Provincial Education Department(Program No.20JS116)。
文摘Pore structure characteristics are significant factor in the evaluation of the physical characteristics of low-rank coal.In this study,three low-rank coal samples were collected from the Xishanyao Formation,Santanghu Basin,and low-temperature liquid-nitrogen adsorption(LP-N2A)measurements were taken under various pretreatment temperatures.Owing to the continuous loss of water and volatile matter in low-rank coal,the total pore volume assumes a three-step profile with knee temperatures of 150°C and 240°C.However,the ash in the coal can protect the coal skeleton.Pore collapse mainly occurs for mesopores with aperture smaller than 20 nm.Mesopores with apertures smaller than 5 nm exhibit a continuous decrease in pore volume,whereas the pore volume of mesopores with apertures ranging from 5 to 10 nm increases at lower pretreatment temperatures(<150°C)followed by a faint decrease.As for mesopores with apertures larger than 10 nm,the pore volume increases significantly when the pretreatment temperature reaches 300°C.The pore structure of low-rank coal features a significant heating effect,the pretreatment temperature should not exceed 150°C when the LP-N2A is used to evaluate the pore structure of low-rank coal to effectively evaluate the reservoir characteristics of low-rank coal.
文摘Based on panel data from 16 cities in Shandong Province from 2013 to 2022,and grounded in theoretical analysis,this paper constructs a benchmark regression model,a mediating effect model,and a heterogeneity test for empirical analysis.The results show that:(1)the digital economy has a significant positive effect on promoting the transformation and upgrading of the manufacturing industry in Shandong Province;(2)the digital economy can drive the transformation and upgrading of the manufacturing industry through technological innovation;and(3)the impact of the digital economy on the transformation and upgrading of the manufacturing industry in Shandong Province is evidently heterogeneous.
基金Sponsored by National Social Science Fund of China(18BGL148)Natural Science Foundation of Inner Mongolia Autonomous Region(2019MS04019)。
文摘Based on the provincial data of tourism and cultural industries from 2009 to 2019,this paper studies the impact of the integration of culture and tourism on the economic benefits of regional tourism in China.The results show that:①The integration level of the two industries is generally low in all provinces and regions,and the regional differences are obvious.The integration degree of the central and eastern regions is generally higher than that of the western regions.②The integration degree of culture and tourism has a significant positive impact on the economic benefits of regional tourism.The influence on the central and eastern regions is greater than that on the western regions.③The level of informatization has a positive moderating effect on the economic benefits of regional tourism caused by the integration of culture and tourism.④Government intervention has a negative moderating effect on the economic benefits of tourism.In addition,the level of regional economic development,accessibility and tourism resource endowment are also significant factors affecting the economic benefits of regional tourism.The results show that promoting the deep integration of culture and tourism,promoting the informatization of tourism and moderate government intervention in the industry are conducive to improving the economic benefits of regional tourism.
