Securitization of economies has received much attention in urban and regional studies,as how the city economy has connected with the capital markets has been increasingly important for a city’s development.This study...Securitization of economies has received much attention in urban and regional studies,as how the city economy has connected with the capital markets has been increasingly important for a city’s development.This study develops a modified Buffett indicator,calculating the ratio of total market capitalization of listed companies to the gross domestic product(GDP)of the city in which these companies are headquartered,to measure city securitization rates(CSR).Drawing on this indicator,this study maps the CSR of all prefecture-and-above level cities in China.It is found that cities with high CSR in China are mainly financial centers and some resource-based cities,while most other cities’CSR are quite low.The regression results show that city’s innovation capacity and political status are positively and significantly associated with the CSR in China.In addition,being close to financial centers can significantly improve the CSR of cities in the eastern region of the country.With the growing financialization of societies,the modified Buffett indicator has a potential to explore the city economy from the perspective of its connection with capital markets in future research.展开更多
Research on high-speed railways is a relatively new yet highly significant field in Vietnam.Among its key components,train control signaling plays a critical role,as it directly affects various interconnected systems,...Research on high-speed railways is a relatively new yet highly significant field in Vietnam.Among its key components,train control signaling plays a critical role,as it directly affects various interconnected systems,including infrastructure,traction power supply,operational planning,and overall railway safety.This article focuses on evaluating the capacity of the line based on the types of signals suitable for high-speed railways that have been effectively implemented in several European countries and successfully adapted in China.The research and simulation are conducted using MATLAB software,a reliable and widely adopted tool in the scientific community.The findings demonstrate that under normal conditions,the European Railway Traffic Management System/European Train Control System(ERTMS/ETCS)Level 2 signaling can support up to 23.7485 trains/hour/direction.Meanwhile,ERTMS/ETCS Level 3 with full moving block can accommodate up to 30.8735 trains/hour/direction,and ERTMS/ETCS Level 3 with fixed virtual blocks up to 29.4694 trains/hour/direction.In emergency scenarios,ERTMS/ETCS Level 3 with full moving block reduces headway by 33.27%compared to CTCS Level 3,while ERTMS/ETCS Level 3 with fixed virtual blocks achieves a 28.78%reduction.Overall,the ERTMS/ETCS Level 3 emerges as a state-of-the-art signaling technology offering high capacity and operational efficiency,and is recommended as a forward-looking solution for future implementation in Vietnam.展开更多
As its tuberous alkaloids induce valuable pharmacological effects,Pinellia ternata has considerable clinical value.However,its production currently fails to meet its demand.In vitro microtuber culture,combined with sa...As its tuberous alkaloids induce valuable pharmacological effects,Pinellia ternata has considerable clinical value.However,its production currently fails to meet its demand.In vitro microtuber culture,combined with salicylic acid(SA)elicitation,may provide an effective alternative to traditional field production.In this study,an in vitro P.ternata microtuber induction system was developed and used to evaluate SA-induced elicitation of alkaloid accumulation.The quality of in vitro microtubers was assessed by total alkaloid measurement,a cytotoxicity assay,and transcriptomic analysis.With or without SA treatment,P.ternata microtuber induction was achieved within 60 d using petiole-derived explants,with a microtuber proliferation rate of approximately 17 microtubers per explant.The total alkaloid content of in vitro microtubers elicited with 100μM SA was equivalent to that of field-grown tubers,while those not treated with SA contained lower alkaloid content.The cytotoxicity assay showed preliminary cytotoxic effects of SA-treated microtubers against the breast cancer cell line SUM159,comparable to field-grown tubers.Transcriptomic analysis revealed many differentially expressed genes(DEGs)in SA-treated in vitro microtubers.Six and twelve DEGs were annotated to the tropane,piperidine,and pyridine alkaloid pathway and the isoquinoline alkaloid pathway,respectively.RT-qPCR confirmed that the genes encoding spermidine synthase(c64642_g1),hyoscyamine(6S)-dioxygenase(c62620_g1),catechol oxidase(c61704_g3),monoamine oxidase(c65996_g3),and aspartate transaminase(c71069_g1)were significantly induced by SA.This study advances the production of P.ternata microtubers without field cultivation and provides considerable genetic information regarding SA-promoted alkaloid accumulation in P.ternata.展开更多
Transforming urban spatial structures to promote green and low-carbon development is an effective strategy.Although prior studies have examined the impact of urban polycentricity on carbon emissions and economic devel...Transforming urban spatial structures to promote green and low-carbon development is an effective strategy.Although prior studies have examined the impact of urban polycentricity on carbon emissions and economic development,research on its role in the synergistic relationship between these factors regarding carbon emission efficiency is limited.Furthermore,existing literature often overlooks nonlinear effects and interactions with other urban variables.This paper analyzed data from 295 Chinese cities in 2020,calculating urban population polycentricity,population dispersion indices,and carbon emission efficiency.Utilizing local spatial autocorrelation tools,we reveal interactions among urban population polycentricity,dispersion,carbon emissions,and carbon emission efficiency.We then employ a gradient boosting decision tree model(GBDT)to explore nonlinear and synergistic effects of polycentric urbanization.Key findings include:1)polycentric urbanization in Chinese cities exhibits significant spatial differentiation characteristics.The Polycentricity index is relatively high in economically developed eastern coastal regions with an overall low level,carbon emissions are concentrated in industrialized north-central cities and some Yangtze River Delta hubs,and carbon emission efficiency is the highest in the Yangtze River Delta while relatively low in Northeast China;there are significant spatially heterogeneous interaction characteristics among population polycentricity,population dispersion,carbon emissions,and carbon emission efficiency.2)Urban population polycentricity contributes 9.42%to total carbon emissions and 6.24%to carbon emission efficiency.3)The polycentricity index has a nonlinear impact on carbon emissions and carbon emission efficiency:no significant effect when below 0.50 or above 0.55,increased carbon emissions in 0.50-0.53,and reduced carbon emissions with improved efficiency in 0.53-0.55.4)The polycentricity index has an interaction effect with other variables;specifically,when the polycentricity index is between 0.53 and 0.55,its interaction with urban gross domestic product(GDP),urban population,urban built-up area,green coverage rate in built-up areas,urban technological expenditure,and the proportion of the output value of the secondary industry will reduce carbon emissions and improve carbon emission efficiency.These findings enhance the understanding of urban spatial structures and carbon emissions,providing valuable insights for policymakers in developing green and low-carbon strategies.展开更多
Objective:To understand the current awareness and willingness to learn about the use of out-of-hospital automated external defibrillators(AEDs)in Deyang City,providing a basis for improving the success rate of rescue ...Objective:To understand the current awareness and willingness to learn about the use of out-of-hospital automated external defibrillators(AEDs)in Deyang City,providing a basis for improving the success rate of rescue operations.Methods:A questionnaire survey was conducted among residents in Deyang City from January 2025 to October 2025,covering residents’basic information,awareness of AED-related knowledge,and attitudes towards AED usage.Results:A total of 1,886 questionnaires were collected,with 1,823 valid questionnaires,yielding an effective rate of 96.66%.Among the 1,823 respondents,692(37.96%)had received cardiopulmonary resuscitation(CPR)-related learning or training,619(33.96%)could accurately describe the name of an AED,417(22.87%)could clearly describe the function of an AED,and 308(16.89%)could accurately describe how to use an AED.Among them,1,549(84.97%)were willing to provide assistance to patients experiencing cardiac arrest;1,731(94.95%)were willing to provide assistance under the premise of knowing how to use an AED;and 1,750(95.99%)were willing to learn about AED-related knowledge.Among the 91 individuals unwilling to provide rescue,75 responded with reasons.Among them,36 cases(48.00%)were reluctant to rescue due to a lack of relevant first aid knowledge,32 cases(42.67%)expressed concerns about exacerbating the patient’s condition due to improper operation,and 4 cases(5.33%)were unwilling to interact with strangers due to personal reasons.Conclusion:Currently,residents in Deyang City have limited knowledge about AEDs but demonstrate a strong willingness to learn and apply them.Measures need to be taken to enhance their understanding and application of AEDs.展开更多
Groundwater and surface water contamination by PTE(Potentially Toxic Elements)was assessed in Ruashi and Annexe municipalities of Lubumbashi city.Analyses of seventy water samples collected from six drilled wells,eigh...Groundwater and surface water contamination by PTE(Potentially Toxic Elements)was assessed in Ruashi and Annexe municipalities of Lubumbashi city.Analyses of seventy water samples collected from six drilled wells,eight spade-sunk wells,one river and one spring in both municipalities in 2017 and 2018 were carried out by ICP-SF-MS(Inductively Coupled Plasma-Sector Field Mass Spectrometry).Twenty PTEs including aluminum,arsenic,barium,bismuth,cadmium,cesium,chromium,cobalt,copper,iron,lead,manganese,molybdenum,nickel,strontium,thallium,tungsten,uranium,vanadium and zinc were detected at various concentrations in each one of the samples.Many samples had concentrations and mean concentrations of PTEs,such as aluminum,cadmium,copper,iron,lead,manganese,nickel and zinc,higher than the respective acceptable limits set for drinking water by the EU(European Union),the USEPA(United States Environmental Protection Agency),and the WHO(World Health Organization)standards.Most PTEs being deleterious to human health even at very low concentrations,people who use the groundwater and surface water to meet their water needs in both Ruashi and Annexe municipalities are at risk.展开更多
The electrochemical corrosion of ductile pipes(DPs)in drinking water distribution systems(DWDS)has a crucial impact on cement-mortar lining(CML)failure and metal release,potentially leading to drinking water quality d...The electrochemical corrosion of ductile pipes(DPs)in drinking water distribution systems(DWDS)has a crucial impact on cement-mortar lining(CML)failure and metal release,potentially leading to drinking water quality deterioration and posing a risk to public health.An in-situ scanning vibrating electrode technique(SVET)with micron-scale resolution,microscopic scale detection and water quality analysis were used to investigate the corrosion behavior and metal release from DPs throughout the whole CML failure process.Metal pollutants release occurred at three different stages of CML failure process,and there are potential risks of water quality deterioration exceeding the maximum allowable levels set by national standards in the partial failure stage and lining peeling stage.Furthermore,the effects of water chemistry(Cl^(−),SO_(4)^(2−),NO_(3)−,and Ca^(2+))on corrosion scale growth and iron release activity,were investigated during the CML partial failure stage.Results showed that the CML failure process in DPs was accelerated by the autocatalysis of localized corrosion.Cl^(−)was found to damage the uncorroded metal surface,while SO_(4)^(2−)mainly dissolved the corrosion scale surface,increasing iron release.Both the oxidation of NO_(3)−and selective sedimentation of Ca2+were found to enhance the stability of corrosion scales and inhibit iron release.展开更多
The reaction of carbon-free oxide-based(corundum,spinel,zirconia,and mullite)submerged entry nozzle(SEN)lining with rare earth inclusions and its anti-clogging effects under near working conditions were systematically...The reaction of carbon-free oxide-based(corundum,spinel,zirconia,and mullite)submerged entry nozzle(SEN)lining with rare earth inclusions and its anti-clogging effects under near working conditions were systematically studied.A variety of lining composite test methods were innovatively used to ensure the consistency of test conditions.The experimental results showed that the mullite(acidic oxide)has strong reactivity with rare earth inclusions,and the spinel(basic oxide)has stable chemical properties and weak reactivity with rare earth inclusions.Because alumina is one of the main reactants of clogging formation,corundum is not suitable for SEN lining.There are less clogs on the surface of zirconia,but it will be exsoluted and unstable.Therefore,solving the problem of zirconia exsolution will greatly strengthen its application in SEN lining.展开更多
As urbanization accelerates globally,air pollution-particularly PM_(2.5)-is becoming an increasingly significant threat,not only to public health but also the environment.In-depth research on the impact of China’s Ze...As urbanization accelerates globally,air pollution-particularly PM_(2.5)-is becoming an increasingly significant threat,not only to public health but also the environment.In-depth research on the impact of China’s Zero Waste City pilot policy on PM_(2.5)concentration offers valuable insights into the policy’s effectiveness and provides a potential model for environmental governance worldwide.This study employs panel data from 293 Chinese cities from 2014 to 2022 to systematically analyze the impact of the Zero-Waste City policy on PM_(2.5)concentration using a difference-in-differences model.The findings indicate that the policy not only directly reduces PM_(2.5)concentration but also indirectly curbs PM_(2.5)emissions by enhancing green innovation and green economic efficiency.Moreover,the policy’s effects are found to be positively moderated by urban energy dependence and digital financial inclusion,while they are negatively moderated by the government debt ratio.Based on these findings,this study suggests that cities should actively develop their digital economy,reduce government debt,promote green innovation,and improve green economic efficiency,as doing so will enhance their implementation of environmental policies and promote sustainable urban development.展开更多
The rapid urbanization and increasing challenges are faced by cities globally,including climate change,population growth,and resource constraints.Sustainable smart city(also referred to as“smart sustainable city”)ca...The rapid urbanization and increasing challenges are faced by cities globally,including climate change,population growth,and resource constraints.Sustainable smart city(also referred to as“smart sustainable city”)can offer innovative solutions by integrating advanced technologies to build smarter,greener,and more livable urban environments with significant benefits.Using the Web of Science(WoS)database,this study examined:(i)the mainstream approaches and current research trends in the literature of sustainable smart city;(ii)the extent to which the research of sustainable smart city aligns with Sustainable Development Goals(SDGs);(iii)the current topics and collaboration patterns in sustainable smart city research;and(iv)the potential opportunities for future research on the sustainable smart city field.The findings indicated that research on sustainable smart city began in 2010 and gained significant momentum in 2013,with China leading,followed by Italy and Spain.Moreover,59.00%of the selected publications on the research of sustainable smart city focus on SDG 11(Sustainable Cities and Communities).Bibliometric analysis outcome revealed that artificial intelligence(AI),big data,machine learning,and deep learning are emerging research fields.The terms smart city,smart cities,and sustainability emerged as the top three co-occurring keywords with the highest link strength,followed by frequently co-occurring keywords such as AI,innovation,big data,urban governance,resilience,machine learning,and Internet of Things(IoT).The clustering results indicated that current studies explored the theoretical foundation,challenges,and future prospects of sustainable smart city,with an emphasis on sustainability.To further support urban sustainability and the attainment of SDGs,the future research of sustainable smart city should explore the application and implications of AI and big data on urban development including cybersecurity and governance challenges.展开更多
Using the new soft X-ray data from the Macao Science Satellite-1,we studied a solar flare that occurred on 22 June 2023.We found that the centroids of the Ca(around 3.9 keV)and Fe(around 6.7 keV)line features exhibit ...Using the new soft X-ray data from the Macao Science Satellite-1,we studied a solar flare that occurred on 22 June 2023.We found that the centroids of the Ca(around 3.9 keV)and Fe(around 6.7 keV)line features exhibit a rapid shift toward higher energy channels during the flare's rising phase,followed by a gradual decrease during the decay phase.Through precise energy calibration,the centroids are determined with high accuracy.Temperature and velocity are then self-consistently derived by comparing the centroids with those calculated from the synthesized line features using the latest CHIANTI atomic database(ver.10.1).The calculated maximum velocity reaches up to 710±60 km s-1,which significantly exceeds the previously reported values.Our results suggest that the entire shift of soft X-ray lines may occur during the process of chromospheric evaporation.展开更多
基金National Natural Science Foundation of China,No.42471195,No.42022006。
文摘Securitization of economies has received much attention in urban and regional studies,as how the city economy has connected with the capital markets has been increasingly important for a city’s development.This study develops a modified Buffett indicator,calculating the ratio of total market capitalization of listed companies to the gross domestic product(GDP)of the city in which these companies are headquartered,to measure city securitization rates(CSR).Drawing on this indicator,this study maps the CSR of all prefecture-and-above level cities in China.It is found that cities with high CSR in China are mainly financial centers and some resource-based cities,while most other cities’CSR are quite low.The regression results show that city’s innovation capacity and political status are positively and significantly associated with the CSR in China.In addition,being close to financial centers can significantly improve the CSR of cities in the eastern region of the country.With the growing financialization of societies,the modified Buffett indicator has a potential to explore the city economy from the perspective of its connection with capital markets in future research.
文摘Research on high-speed railways is a relatively new yet highly significant field in Vietnam.Among its key components,train control signaling plays a critical role,as it directly affects various interconnected systems,including infrastructure,traction power supply,operational planning,and overall railway safety.This article focuses on evaluating the capacity of the line based on the types of signals suitable for high-speed railways that have been effectively implemented in several European countries and successfully adapted in China.The research and simulation are conducted using MATLAB software,a reliable and widely adopted tool in the scientific community.The findings demonstrate that under normal conditions,the European Railway Traffic Management System/European Train Control System(ERTMS/ETCS)Level 2 signaling can support up to 23.7485 trains/hour/direction.Meanwhile,ERTMS/ETCS Level 3 with full moving block can accommodate up to 30.8735 trains/hour/direction,and ERTMS/ETCS Level 3 with fixed virtual blocks up to 29.4694 trains/hour/direction.In emergency scenarios,ERTMS/ETCS Level 3 with full moving block reduces headway by 33.27%compared to CTCS Level 3,while ERTMS/ETCS Level 3 with fixed virtual blocks achieves a 28.78%reduction.Overall,the ERTMS/ETCS Level 3 emerges as a state-of-the-art signaling technology offering high capacity and operational efficiency,and is recommended as a forward-looking solution for future implementation in Vietnam.
基金supported by the Key Project of Natural Science Research for Colleges and Universities in Anhui Province(2024AH051661,2023AH050345)Excellent Scientific Research and Innovation Team of University in Anhui Province(2022AH010029).
文摘As its tuberous alkaloids induce valuable pharmacological effects,Pinellia ternata has considerable clinical value.However,its production currently fails to meet its demand.In vitro microtuber culture,combined with salicylic acid(SA)elicitation,may provide an effective alternative to traditional field production.In this study,an in vitro P.ternata microtuber induction system was developed and used to evaluate SA-induced elicitation of alkaloid accumulation.The quality of in vitro microtubers was assessed by total alkaloid measurement,a cytotoxicity assay,and transcriptomic analysis.With or without SA treatment,P.ternata microtuber induction was achieved within 60 d using petiole-derived explants,with a microtuber proliferation rate of approximately 17 microtubers per explant.The total alkaloid content of in vitro microtubers elicited with 100μM SA was equivalent to that of field-grown tubers,while those not treated with SA contained lower alkaloid content.The cytotoxicity assay showed preliminary cytotoxic effects of SA-treated microtubers against the breast cancer cell line SUM159,comparable to field-grown tubers.Transcriptomic analysis revealed many differentially expressed genes(DEGs)in SA-treated in vitro microtubers.Six and twelve DEGs were annotated to the tropane,piperidine,and pyridine alkaloid pathway and the isoquinoline alkaloid pathway,respectively.RT-qPCR confirmed that the genes encoding spermidine synthase(c64642_g1),hyoscyamine(6S)-dioxygenase(c62620_g1),catechol oxidase(c61704_g3),monoamine oxidase(c65996_g3),and aspartate transaminase(c71069_g1)were significantly induced by SA.This study advances the production of P.ternata microtubers without field cultivation and provides considerable genetic information regarding SA-promoted alkaloid accumulation in P.ternata.
基金Under the auspices of National Natural Science Foundation of China(No.42571300)。
文摘Transforming urban spatial structures to promote green and low-carbon development is an effective strategy.Although prior studies have examined the impact of urban polycentricity on carbon emissions and economic development,research on its role in the synergistic relationship between these factors regarding carbon emission efficiency is limited.Furthermore,existing literature often overlooks nonlinear effects and interactions with other urban variables.This paper analyzed data from 295 Chinese cities in 2020,calculating urban population polycentricity,population dispersion indices,and carbon emission efficiency.Utilizing local spatial autocorrelation tools,we reveal interactions among urban population polycentricity,dispersion,carbon emissions,and carbon emission efficiency.We then employ a gradient boosting decision tree model(GBDT)to explore nonlinear and synergistic effects of polycentric urbanization.Key findings include:1)polycentric urbanization in Chinese cities exhibits significant spatial differentiation characteristics.The Polycentricity index is relatively high in economically developed eastern coastal regions with an overall low level,carbon emissions are concentrated in industrialized north-central cities and some Yangtze River Delta hubs,and carbon emission efficiency is the highest in the Yangtze River Delta while relatively low in Northeast China;there are significant spatially heterogeneous interaction characteristics among population polycentricity,population dispersion,carbon emissions,and carbon emission efficiency.2)Urban population polycentricity contributes 9.42%to total carbon emissions and 6.24%to carbon emission efficiency.3)The polycentricity index has a nonlinear impact on carbon emissions and carbon emission efficiency:no significant effect when below 0.50 or above 0.55,increased carbon emissions in 0.50-0.53,and reduced carbon emissions with improved efficiency in 0.53-0.55.4)The polycentricity index has an interaction effect with other variables;specifically,when the polycentricity index is between 0.53 and 0.55,its interaction with urban gross domestic product(GDP),urban population,urban built-up area,green coverage rate in built-up areas,urban technological expenditure,and the proportion of the output value of the secondary industry will reduce carbon emissions and improve carbon emission efficiency.These findings enhance the understanding of urban spatial structures and carbon emissions,providing valuable insights for policymakers in developing green and low-carbon strategies.
文摘Objective:To understand the current awareness and willingness to learn about the use of out-of-hospital automated external defibrillators(AEDs)in Deyang City,providing a basis for improving the success rate of rescue operations.Methods:A questionnaire survey was conducted among residents in Deyang City from January 2025 to October 2025,covering residents’basic information,awareness of AED-related knowledge,and attitudes towards AED usage.Results:A total of 1,886 questionnaires were collected,with 1,823 valid questionnaires,yielding an effective rate of 96.66%.Among the 1,823 respondents,692(37.96%)had received cardiopulmonary resuscitation(CPR)-related learning or training,619(33.96%)could accurately describe the name of an AED,417(22.87%)could clearly describe the function of an AED,and 308(16.89%)could accurately describe how to use an AED.Among them,1,549(84.97%)were willing to provide assistance to patients experiencing cardiac arrest;1,731(94.95%)were willing to provide assistance under the premise of knowing how to use an AED;and 1,750(95.99%)were willing to learn about AED-related knowledge.Among the 91 individuals unwilling to provide rescue,75 responded with reasons.Among them,36 cases(48.00%)were reluctant to rescue due to a lack of relevant first aid knowledge,32 cases(42.67%)expressed concerns about exacerbating the patient’s condition due to improper operation,and 4 cases(5.33%)were unwilling to interact with strangers due to personal reasons.Conclusion:Currently,residents in Deyang City have limited knowledge about AEDs but demonstrate a strong willingness to learn and apply them.Measures need to be taken to enhance their understanding and application of AEDs.
基金funding received from UNESCO-SIDA Project as well as Professor Martine Leermakers and Professor Willy Baeyens for their financial help to analyze the water samples in their laboratory at VUB.Acknowledgements
文摘Groundwater and surface water contamination by PTE(Potentially Toxic Elements)was assessed in Ruashi and Annexe municipalities of Lubumbashi city.Analyses of seventy water samples collected from six drilled wells,eight spade-sunk wells,one river and one spring in both municipalities in 2017 and 2018 were carried out by ICP-SF-MS(Inductively Coupled Plasma-Sector Field Mass Spectrometry).Twenty PTEs including aluminum,arsenic,barium,bismuth,cadmium,cesium,chromium,cobalt,copper,iron,lead,manganese,molybdenum,nickel,strontium,thallium,tungsten,uranium,vanadium and zinc were detected at various concentrations in each one of the samples.Many samples had concentrations and mean concentrations of PTEs,such as aluminum,cadmium,copper,iron,lead,manganese,nickel and zinc,higher than the respective acceptable limits set for drinking water by the EU(European Union),the USEPA(United States Environmental Protection Agency),and the WHO(World Health Organization)standards.Most PTEs being deleterious to human health even at very low concentrations,people who use the groundwater and surface water to meet their water needs in both Ruashi and Annexe municipalities are at risk.
基金supported by the National Natural Science Foundation of China(Nos.51808158,52170101,and 52200116)Tianjin Natural Science Foundation(No.23JCYBJC00640).
文摘The electrochemical corrosion of ductile pipes(DPs)in drinking water distribution systems(DWDS)has a crucial impact on cement-mortar lining(CML)failure and metal release,potentially leading to drinking water quality deterioration and posing a risk to public health.An in-situ scanning vibrating electrode technique(SVET)with micron-scale resolution,microscopic scale detection and water quality analysis were used to investigate the corrosion behavior and metal release from DPs throughout the whole CML failure process.Metal pollutants release occurred at three different stages of CML failure process,and there are potential risks of water quality deterioration exceeding the maximum allowable levels set by national standards in the partial failure stage and lining peeling stage.Furthermore,the effects of water chemistry(Cl^(−),SO_(4)^(2−),NO_(3)−,and Ca^(2+))on corrosion scale growth and iron release activity,were investigated during the CML partial failure stage.Results showed that the CML failure process in DPs was accelerated by the autocatalysis of localized corrosion.Cl^(−)was found to damage the uncorroded metal surface,while SO_(4)^(2−)mainly dissolved the corrosion scale surface,increasing iron release.Both the oxidation of NO_(3)−and selective sedimentation of Ca2+were found to enhance the stability of corrosion scales and inhibit iron release.
基金supported by the National Outstanding Youth Science Fund Project of National Natural Science Foundation of China(52302031)National Natural Science Foundation of China(51932008 and 51772277)Central China Thousand Talents Project(204200510011).
文摘The reaction of carbon-free oxide-based(corundum,spinel,zirconia,and mullite)submerged entry nozzle(SEN)lining with rare earth inclusions and its anti-clogging effects under near working conditions were systematically studied.A variety of lining composite test methods were innovatively used to ensure the consistency of test conditions.The experimental results showed that the mullite(acidic oxide)has strong reactivity with rare earth inclusions,and the spinel(basic oxide)has stable chemical properties and weak reactivity with rare earth inclusions.Because alumina is one of the main reactants of clogging formation,corundum is not suitable for SEN lining.There are less clogs on the surface of zirconia,but it will be exsoluted and unstable.Therefore,solving the problem of zirconia exsolution will greatly strengthen its application in SEN lining.
基金The authors declare that fund support was received from National Social Science Fund of China[Grant No.23BJL010].
文摘As urbanization accelerates globally,air pollution-particularly PM_(2.5)-is becoming an increasingly significant threat,not only to public health but also the environment.In-depth research on the impact of China’s Zero Waste City pilot policy on PM_(2.5)concentration offers valuable insights into the policy’s effectiveness and provides a potential model for environmental governance worldwide.This study employs panel data from 293 Chinese cities from 2014 to 2022 to systematically analyze the impact of the Zero-Waste City policy on PM_(2.5)concentration using a difference-in-differences model.The findings indicate that the policy not only directly reduces PM_(2.5)concentration but also indirectly curbs PM_(2.5)emissions by enhancing green innovation and green economic efficiency.Moreover,the policy’s effects are found to be positively moderated by urban energy dependence and digital financial inclusion,while they are negatively moderated by the government debt ratio.Based on these findings,this study suggests that cities should actively develop their digital economy,reduce government debt,promote green innovation,and improve green economic efficiency,as doing so will enhance their implementation of environmental policies and promote sustainable urban development.
文摘The rapid urbanization and increasing challenges are faced by cities globally,including climate change,population growth,and resource constraints.Sustainable smart city(also referred to as“smart sustainable city”)can offer innovative solutions by integrating advanced technologies to build smarter,greener,and more livable urban environments with significant benefits.Using the Web of Science(WoS)database,this study examined:(i)the mainstream approaches and current research trends in the literature of sustainable smart city;(ii)the extent to which the research of sustainable smart city aligns with Sustainable Development Goals(SDGs);(iii)the current topics and collaboration patterns in sustainable smart city research;and(iv)the potential opportunities for future research on the sustainable smart city field.The findings indicated that research on sustainable smart city began in 2010 and gained significant momentum in 2013,with China leading,followed by Italy and Spain.Moreover,59.00%of the selected publications on the research of sustainable smart city focus on SDG 11(Sustainable Cities and Communities).Bibliometric analysis outcome revealed that artificial intelligence(AI),big data,machine learning,and deep learning are emerging research fields.The terms smart city,smart cities,and sustainability emerged as the top three co-occurring keywords with the highest link strength,followed by frequently co-occurring keywords such as AI,innovation,big data,urban governance,resilience,machine learning,and Internet of Things(IoT).The clustering results indicated that current studies explored the theoretical foundation,challenges,and future prospects of sustainable smart city,with an emphasis on sustainability.To further support urban sustainability and the attainment of SDGs,the future research of sustainable smart city should explore the application and implications of AI and big data on urban development including cybersecurity and governance challenges.
文摘Using the new soft X-ray data from the Macao Science Satellite-1,we studied a solar flare that occurred on 22 June 2023.We found that the centroids of the Ca(around 3.9 keV)and Fe(around 6.7 keV)line features exhibit a rapid shift toward higher energy channels during the flare's rising phase,followed by a gradual decrease during the decay phase.Through precise energy calibration,the centroids are determined with high accuracy.Temperature and velocity are then self-consistently derived by comparing the centroids with those calculated from the synthesized line features using the latest CHIANTI atomic database(ver.10.1).The calculated maximum velocity reaches up to 710±60 km s-1,which significantly exceeds the previously reported values.Our results suggest that the entire shift of soft X-ray lines may occur during the process of chromospheric evaporation.
