Typhoon disasters threaten sustainable development in southeastern China due to their complex spatiotemporal chaining and compounding effects.However,characteristics of risk and exposure of compound typhoon disaster c...Typhoon disasters threaten sustainable development in southeastern China due to their complex spatiotemporal chaining and compounding effects.However,characteristics of risk and exposure of compound typhoon disaster chains remain unclear,particularly across geographic scales.This study proposed a multi-scale risk assessment framework to analyze compound typhoon disaster chains,using Fujian Province—a high-risk coastal region in southeastern China—as a case study.We quantified risks and exposures of four disaster chains:typhoon-rainstorm-urban waterlogging(TRU),typhoon-rainstormflood(TRF),typhoon-rainstorm-landslide(TRL),and typhoon-strong wind-storm surge(TWS),across nested scales(grid,county,city,and basin).Key findings include:(1)Pronounced spatial heterogeneity exists in Fujian Province,with compound risk hotspots dominated by TRU(216.71 km2),TRF(872.43 km2),and TWS(263.69 km2)high-risk areas in eastern coastal areas,while inland mountainous regions are primarily affected by the TRL single chain(24,993 km2,20.4%of the total area of the province);(2)Approximately one-third of the provincial population(5.69 million)and GDP(RMB 552 billion yuan)are exposed to the high-risk zones of the TRF chain,whereas the TRU chain results in twice the exposure density of TRF,forming localized hotspots;(3)High-risk areas display dual patterns of single chain dominance and compound chain aggregation,with compound chain exposure densities 38–58 times higher(at population density 15,900 persons/km2)than single chain exposure density.Priority should be given to managing cascading risks of compound chains like TRU-TRF,alongside targeted interventions in multi-disaster hubs such as Fuzhou City and Jinjiang City.The findings advance our understanding of typhoon disaster risk compounding,informing targeted mitigation strategies and providing a framework for multi-hazard cascade analysis.展开更多
An anomalous phase containing clays and humic acid was found while extraction humic acid from samples of weathering crust of REE-bearing granites by using 0.1 mol/L NaOH solution.Studied by chemical separation experim...An anomalous phase containing clays and humic acid was found while extraction humic acid from samples of weathering crust of REE-bearing granites by using 0.1 mol/L NaOH solution.Studied by chemical separation experiments,column chromatography,ion-exchange chromatography,infrared spectrum.fluorescence spectrum,polarimicroscopic testing and elemental determination by ultraviolet-visible spectrometer and atomic absorption spectrometer.it was proved to be a compound of humic acid and clays which are connected in the form of bridge by heteronuclearpolynuclear complexing ions formed by cations of RE￣(5+),Al￣(3+).Fe￣(3+) etc.The compounding pattern was further proved by the experiment for compounding humic acid,REE and kaolinite.展开更多
At present CALPHAD (CALculation of PHAse Diagram) technique is notcapable of predicting whether there exists intermediate compound,much less predicting the formulae, the number, and the meltingcongruence of intermedi-...At present CALPHAD (CALculation of PHAse Diagram) technique is notcapable of predicting whether there exists intermediate compound,much less predicting the formulae, the number, and the meltingcongruence of intermedi- ate compounds. To solve this problem, a newapproach called the phase diagram evaluation by pattern recognition(PDEPR) was improved. The micro-parameters. Such as the radius andthe electronegativity of the different features in multi-dimensionalspace.展开更多
The formability of complex flourides has been studied by chemical bond parameter-pattern recognition method. In a multi-dimensional space spanned by ionic radius, ionic polarizability, electronegativity and ionic char...The formability of complex flourides has been studied by chemical bond parameter-pattern recognition method. In a multi-dimensional space spanned by ionic radius, ionic polarizability, electronegativity and ionic charge of the metal elements, the binary complex flouride-forming systems and binary flouride systems without complex flouride formation distribute in different regions with a clear-cut boundary. The mathematical models obtained are useful for new complex flouride predicton.展开更多
基金funded by the National Natural Science Foundation of China(Grant No.42271030)Fujian Provincial Funds for Distinguished Young Scientists(Grant No.2022J06018)“Young Eagle Plan”Top Talents of Fujian Province。
文摘Typhoon disasters threaten sustainable development in southeastern China due to their complex spatiotemporal chaining and compounding effects.However,characteristics of risk and exposure of compound typhoon disaster chains remain unclear,particularly across geographic scales.This study proposed a multi-scale risk assessment framework to analyze compound typhoon disaster chains,using Fujian Province—a high-risk coastal region in southeastern China—as a case study.We quantified risks and exposures of four disaster chains:typhoon-rainstorm-urban waterlogging(TRU),typhoon-rainstormflood(TRF),typhoon-rainstorm-landslide(TRL),and typhoon-strong wind-storm surge(TWS),across nested scales(grid,county,city,and basin).Key findings include:(1)Pronounced spatial heterogeneity exists in Fujian Province,with compound risk hotspots dominated by TRU(216.71 km2),TRF(872.43 km2),and TWS(263.69 km2)high-risk areas in eastern coastal areas,while inland mountainous regions are primarily affected by the TRL single chain(24,993 km2,20.4%of the total area of the province);(2)Approximately one-third of the provincial population(5.69 million)and GDP(RMB 552 billion yuan)are exposed to the high-risk zones of the TRF chain,whereas the TRU chain results in twice the exposure density of TRF,forming localized hotspots;(3)High-risk areas display dual patterns of single chain dominance and compound chain aggregation,with compound chain exposure densities 38–58 times higher(at population density 15,900 persons/km2)than single chain exposure density.Priority should be given to managing cascading risks of compound chains like TRU-TRF,alongside targeted interventions in multi-disaster hubs such as Fuzhou City and Jinjiang City.The findings advance our understanding of typhoon disaster risk compounding,informing targeted mitigation strategies and providing a framework for multi-hazard cascade analysis.
文摘An anomalous phase containing clays and humic acid was found while extraction humic acid from samples of weathering crust of REE-bearing granites by using 0.1 mol/L NaOH solution.Studied by chemical separation experiments,column chromatography,ion-exchange chromatography,infrared spectrum.fluorescence spectrum,polarimicroscopic testing and elemental determination by ultraviolet-visible spectrometer and atomic absorption spectrometer.it was proved to be a compound of humic acid and clays which are connected in the form of bridge by heteronuclearpolynuclear complexing ions formed by cations of RE￣(5+),Al￣(3+).Fe￣(3+) etc.The compounding pattern was further proved by the experiment for compounding humic acid,REE and kaolinite.
基金the National Natural Science Foundation of China (No. 50071009), the Foundation of Natural Science of Anhui Province 00046509, t
文摘At present CALPHAD (CALculation of PHAse Diagram) technique is notcapable of predicting whether there exists intermediate compound,much less predicting the formulae, the number, and the meltingcongruence of intermedi- ate compounds. To solve this problem, a newapproach called the phase diagram evaluation by pattern recognition(PDEPR) was improved. The micro-parameters. Such as the radius andthe electronegativity of the different features in multi-dimensionalspace.
文摘The formability of complex flourides has been studied by chemical bond parameter-pattern recognition method. In a multi-dimensional space spanned by ionic radius, ionic polarizability, electronegativity and ionic charge of the metal elements, the binary complex flouride-forming systems and binary flouride systems without complex flouride formation distribute in different regions with a clear-cut boundary. The mathematical models obtained are useful for new complex flouride predicton.
