Rapidly expanding studies investigate the effects of e-commerce on company operations in the retail market.However,the interaction between agri-food e-commerce(AEC)and the traditional agri-food wholesale industry(AWI)...Rapidly expanding studies investigate the effects of e-commerce on company operations in the retail market.However,the interaction between agri-food e-commerce(AEC)and the traditional agri-food wholesale industry(AWI)has not received enough attention in the existing literature.Based on the provincial panel data from 2013 to 2020 in China,this paper examines the effect of AEC on AWI,comprising three dimensions:digitalization(DIGITAL),agrifood e-commerce infrastructure and supporting services(AECI),and agri-food e-commerce economy(AECE).First,AWI and AEC are measured using an entropy-based combination of indicators.The results indicate that for China as a whole,AWI has remained practically unchanged,whereas AEC exhibits a significant rising trend.Second,the findings of the fixed-effect regression reveal that DIGITAL and AECE tend to raise AWI,whereas AECI negatively affects AWI.Third,threshold regression results indicate that AECI tends to diminish AWI with three-stage inhibitory intensity,which manifests as a first increase and then a drop in the inhibition degree.These results suggest that with the introduction of e-commerce for agricultural product circulation,digital development will have catfish effects that tend to stimulate the vitality of the conventional wholesale industry and promote technical progress.Furthermore,the traditional wholesale industry benefits financially from e-commerce even while it diverts part of the traditional wholesale circulation for agricultural products.展开更多
Developing the highly efficient and durable non-precious metal electrocatalysts by taking advantage of inexpensive and abundant resources is of paramount importance for the widespread application of energy conversion ...Developing the highly efficient and durable non-precious metal electrocatalysts by taking advantage of inexpensive and abundant resources is of paramount importance for the widespread application of energy conversion and storage techniques such as fuel cells and metal-air batteries.Herein,the sponge-like unadulterated carbontube-graphene complexes(D/G-CTs-1,000)with multifarious intrinsic defect active sites are fabricated by boric acid-hydrothermal and pyrolysis treatments.The close contact or juncture between open nanotubes and few-layer graphene in D/G-CTs-1,000 constructs the hierarchical networks with plentifuchannels,the larger surface area and outstanding conductivity.As a result,the as-prepared D/G-CTs-1,000 electrocatalyst exhibits an excellent trifunctional electrocatalytic performance for oxygen reduction reaction(ORR),oxygen evolution reactior(OER)and hydrogen evolution reaction(HER).The primary Zn-air batteries and overall water splitting system using D/G-CTs-1,000 as the electrode materials delivers higher power density outperforming the advanced Pt/C-based batteries and the overall watersplitting performance comparable to those using the non-precious metal/carbon-based materials as electrode.This work provides a universal and efficient synthetic strategy to produce the unadulterated carbons with high activity and long-time durability as trifunctional electrocatalysts and promote the widespread applications of metal-free electrocatalysts in sustainable energy conversior technology.展开更多
基金supported by the Leading Talent Support Program for Agricultural Talents of the Chinese Academy of Agricultural Sciences(TCS2022020)the General program of National Natural Science Foundation of China(1573263)。
文摘Rapidly expanding studies investigate the effects of e-commerce on company operations in the retail market.However,the interaction between agri-food e-commerce(AEC)and the traditional agri-food wholesale industry(AWI)has not received enough attention in the existing literature.Based on the provincial panel data from 2013 to 2020 in China,this paper examines the effect of AEC on AWI,comprising three dimensions:digitalization(DIGITAL),agrifood e-commerce infrastructure and supporting services(AECI),and agri-food e-commerce economy(AECE).First,AWI and AEC are measured using an entropy-based combination of indicators.The results indicate that for China as a whole,AWI has remained practically unchanged,whereas AEC exhibits a significant rising trend.Second,the findings of the fixed-effect regression reveal that DIGITAL and AECE tend to raise AWI,whereas AECI negatively affects AWI.Third,threshold regression results indicate that AECI tends to diminish AWI with three-stage inhibitory intensity,which manifests as a first increase and then a drop in the inhibition degree.These results suggest that with the introduction of e-commerce for agricultural product circulation,digital development will have catfish effects that tend to stimulate the vitality of the conventional wholesale industry and promote technical progress.Furthermore,the traditional wholesale industry benefits financially from e-commerce even while it diverts part of the traditional wholesale circulation for agricultural products.
基金The authors are grateful to financial support from the NationalNatural Science Foundation of China(No.21303058)the Natural Science Foundation of Shanghai(No.13ZR1412400)the Science and Technology Commission of Shanghai Municipality(Nos.11JC1403400 and 14231200300).
文摘Developing the highly efficient and durable non-precious metal electrocatalysts by taking advantage of inexpensive and abundant resources is of paramount importance for the widespread application of energy conversion and storage techniques such as fuel cells and metal-air batteries.Herein,the sponge-like unadulterated carbontube-graphene complexes(D/G-CTs-1,000)with multifarious intrinsic defect active sites are fabricated by boric acid-hydrothermal and pyrolysis treatments.The close contact or juncture between open nanotubes and few-layer graphene in D/G-CTs-1,000 constructs the hierarchical networks with plentifuchannels,the larger surface area and outstanding conductivity.As a result,the as-prepared D/G-CTs-1,000 electrocatalyst exhibits an excellent trifunctional electrocatalytic performance for oxygen reduction reaction(ORR),oxygen evolution reactior(OER)and hydrogen evolution reaction(HER).The primary Zn-air batteries and overall water splitting system using D/G-CTs-1,000 as the electrode materials delivers higher power density outperforming the advanced Pt/C-based batteries and the overall watersplitting performance comparable to those using the non-precious metal/carbon-based materials as electrode.This work provides a universal and efficient synthetic strategy to produce the unadulterated carbons with high activity and long-time durability as trifunctional electrocatalysts and promote the widespread applications of metal-free electrocatalysts in sustainable energy conversior technology.