A new conjugated hyperbranched polymer （hb-TFO） containing tetraphenylethylene （TPE） units, a famous aggregation-induced emission （AIE） active group, as the core, was synthesized successfully with modest yield v...A new conjugated hyperbranched polymer （hb-TFO） containing tetraphenylethylene （TPE） units, a famous aggregation-induced emission （AIE） active group, as the core, was synthesized successfully with modest yield via one-pot Suzuki polymerization reaction. Thanks to the introduction of TPE moieties, hb-TFO exhibited aggregation-enhanced emission （AEE） property, and could work as explosive chemosensor with high sensitivity. The polymeric light-emitting diode （PLED） device was fabricated to investigate its electroluminescent property, and hb-TFO demonstrated a maximum luminance efficiency of 0.22 cd/A and a maximum brightness of 545 cd/m2 at 15.9 V.展开更多
As a traditional agricultural country,China has always prioritized agricultural development,and has increasingly focused on green and sustainable agricultural development.Based on the inter-provincial panel data for C...As a traditional agricultural country,China has always prioritized agricultural development,and has increasingly focused on green and sustainable agricultural development.Based on the inter-provincial panel data for China from 1997 to 2019,this study divided these data into five periods according to the Five-Year Plan(FYP)of China,measured the agricultural eco-efficiency(AEE)values using the Super-SBM model,and then determined the spatial association network of the inter-provincial AEE of China using the improved gravity model.Finally,social network analysis(SNA)was used to further analyze the evolution process of AEE,and we de-veloped a framework of how multidimensional proximity,which includes geographical,economic,technological,cognitive,and institutional proximity,made an influence on the formation of AEE spatial relation network.The findings indicated that:1)in 1997−2019,the AEE in China was present in some spatial and temporal differences characteristics at the provincial scale,and we specifically found that national macro-regulation and policy incentives played a positive role in the long-term development of AEE.2)The spatial correlation of AEE development among provincial regions were becoming closer and exhibits obvious spatial correlation and spillover effects.The evolution of the AEE network has clearly observable trends of hierarchization and aggregation,and the complexity of the correlation network continues to increase and exhibits spatial clustering characteristics that are dense in the east and sparse in the west.The network structure has changed from monocentric radiation to a multicentric network,and network nodes select the more advantageous nodes with which to connect.3)Finally,the geographical proximity had a significant negative effect;the economic,technological,and institutional proximities were all observed to contribute to the AEE network formation,and cognitive proximity did not significantly influence this network formation.展开更多
s: The current status of AEE in Hunan Province is introduced in brief. The reasons why the AEE was polluted and destroyed are analyzed; the countermeasures for improving AEE are brought forward.
文摘A new conjugated hyperbranched polymer （hb-TFO） containing tetraphenylethylene （TPE） units, a famous aggregation-induced emission （AIE） active group, as the core, was synthesized successfully with modest yield via one-pot Suzuki polymerization reaction. Thanks to the introduction of TPE moieties, hb-TFO exhibited aggregation-enhanced emission （AEE） property, and could work as explosive chemosensor with high sensitivity. The polymeric light-emitting diode （PLED） device was fabricated to investigate its electroluminescent property, and hb-TFO demonstrated a maximum luminance efficiency of 0.22 cd/A and a maximum brightness of 545 cd/m2 at 15.9 V.
基金Under the auspices of National Key R&D Program of China(No.2018YFD 1100104)Natural Science Foundation of Anhui Province(No.2108085-MD29)National Natural Science Foundation of China(No.41571400)。
文摘As a traditional agricultural country,China has always prioritized agricultural development,and has increasingly focused on green and sustainable agricultural development.Based on the inter-provincial panel data for China from 1997 to 2019,this study divided these data into five periods according to the Five-Year Plan(FYP)of China,measured the agricultural eco-efficiency(AEE)values using the Super-SBM model,and then determined the spatial association network of the inter-provincial AEE of China using the improved gravity model.Finally,social network analysis(SNA)was used to further analyze the evolution process of AEE,and we de-veloped a framework of how multidimensional proximity,which includes geographical,economic,technological,cognitive,and institutional proximity,made an influence on the formation of AEE spatial relation network.The findings indicated that:1)in 1997−2019,the AEE in China was present in some spatial and temporal differences characteristics at the provincial scale,and we specifically found that national macro-regulation and policy incentives played a positive role in the long-term development of AEE.2)The spatial correlation of AEE development among provincial regions were becoming closer and exhibits obvious spatial correlation and spillover effects.The evolution of the AEE network has clearly observable trends of hierarchization and aggregation,and the complexity of the correlation network continues to increase and exhibits spatial clustering characteristics that are dense in the east and sparse in the west.The network structure has changed from monocentric radiation to a multicentric network,and network nodes select the more advantageous nodes with which to connect.3)Finally,the geographical proximity had a significant negative effect;the economic,technological,and institutional proximities were all observed to contribute to the AEE network formation,and cognitive proximity did not significantly influence this network formation.
文摘s: The current status of AEE in Hunan Province is introduced in brief. The reasons why the AEE was polluted and destroyed are analyzed; the countermeasures for improving AEE are brought forward.
