At present,the interpretation of regional economic development(RED)has changed from a simple evaluation of economic growth to a focus on economic growth and the optimization of economic structure,the improvement of ec...At present,the interpretation of regional economic development(RED)has changed from a simple evaluation of economic growth to a focus on economic growth and the optimization of economic structure,the improvement of economic relations,and the change of institutional innovation.This article uses the RED trend as the research object and constructs the RED index to conduct the theoretical analysis.Then this paper uses the attention mechanism based on digital twins and the time series network model to verify the actual data.Finally,the regional economy is predicted according to the theoretical model.The specific research work mainly includes the following aspects:1)This paper introduced the development status of research on time series networks and economic forecasting at home and abroad.2)This paper introduces the basic principles and structures of long and short-term memory(LSTM)and convolutional neural network(CNN),constructs an improved CNN-LSTM model combined with the attention mechanism,and then constructs a regional economic prediction index system.3)The best parameters of the model are selected through experiments,and the trained model is used for simulation experiment prediction.The results show that the CNN-LSTM model based on the attentionmechanism proposed in this paper has high accuracy in predicting regional economies.展开更多
As one of the most promising Kitaev quantum-spin-liquid(QSL)candidates,α-RuCl_(3)has received a great deal of attention.However,its ground state exhibits a long-range zigzag magnetic order,which defies the QSL phase....As one of the most promising Kitaev quantum-spin-liquid(QSL)candidates,α-RuCl_(3)has received a great deal of attention.However,its ground state exhibits a long-range zigzag magnetic order,which defies the QSL phase.Nevertheless,the magnetic order is fragile and can be completely suppressed by applying an external magnetic field.Here,we explore the evolution of magnetic excitations ofα-RuCl;under an in-plane magnetic field,by carrying out inelastic neutron scattering measurements on high-quality single crystals.Under zero field,there exist spin-wave excitations near the M point and a continuum near theΓpoint,which are believed to be associated with the zigzag magnetic order and fractional excitations of the Kitaev QSL state,respectively.By increasing the magnetic field,the spin-wave excitations gradually give way to the continuous excitations.On the verge of the critical fieldμ_(0)H_(c)=7.5 T,the former ones vanish and only the latter ones are left,indicating the emergence of a pure QSL state.By further increasing the field strength,the excitations near theΓpoint become more intense.By following the gap evolution of the excitations near theΓpoint,we are able to establish a phase diagram composed of three interesting phases,including a gapped zigzag order phase at low fields,possibly gapless QSL phase nearμ;H;,and gapped partially polarized phase at high fields.These results demonstrate that an in-plane magnetic field can driveα-RuCl;into a long-sought QSL state near the critical field.展开更多
Thanks to the synergistic effect,the bimetallic catalysts show better catalytic activity than the single metal cat-alysts and become a focus of research in heterogeneous catalysis.In this study,we successfully prepare...Thanks to the synergistic effect,the bimetallic catalysts show better catalytic activity than the single metal cat-alysts and become a focus of research in heterogeneous catalysis.In this study,we successfully prepared Pd-Pt icosahedra which show high peroxidase-like activity under the synergistic effects of Pd and Pt.V max of the Pd-Pt icosahedra was significantly enhanced by 1.66 times for 3,3’,5,5’-tetramethylbenzidine(TMB)as the substrate and 1.23 times for H_(2)O_(2) as the substrate,compared to that of the Pd icosahedra alone.By harnessing the supe-rior peroxidase-like activity of Pd-Pt icosahedra,we successfully utilized Pd-Pt icosahedral nanozymes in various biological analyses based on colorimetry.In most cases,using a Pd-Pt icosahedra/H_(2)O_(2)/TMB system,glucose,glutathione(GSH),acid phosphatase(ACP),and alkaline phosphatase(ALP)were detected over a wide range of 0.05∼0.20 mM,0∼20 mM,0∼10 U/L and 0∼12 U/L.In this study,we prepared a novel bimetallic nanozyme that exhibited excellent peroxidase-like activity owing to the bimetallic synergistic effect,thus demonstrating the promising potential of Pd-Pt icosahedra in the field of bioanalysis.展开更多
文摘At present,the interpretation of regional economic development(RED)has changed from a simple evaluation of economic growth to a focus on economic growth and the optimization of economic structure,the improvement of economic relations,and the change of institutional innovation.This article uses the RED trend as the research object and constructs the RED index to conduct the theoretical analysis.Then this paper uses the attention mechanism based on digital twins and the time series network model to verify the actual data.Finally,the regional economy is predicted according to the theoretical model.The specific research work mainly includes the following aspects:1)This paper introduced the development status of research on time series networks and economic forecasting at home and abroad.2)This paper introduces the basic principles and structures of long and short-term memory(LSTM)and convolutional neural network(CNN),constructs an improved CNN-LSTM model combined with the attention mechanism,and then constructs a regional economic prediction index system.3)The best parameters of the model are selected through experiments,and the trained model is used for simulation experiment prediction.The results show that the CNN-LSTM model based on the attentionmechanism proposed in this paper has high accuracy in predicting regional economies.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFA1400400)the National Natural Science Foundation of China(Grant Nos.11822405,12074174,12074175,92165205,11904170,12004249,12004251,and 12004191)+1 种基金the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20180006,BK20190436,and BK20200738)the Shanghai Sailing Program(Grant Nos.20YF1430600 and 21YF1429200)。
文摘As one of the most promising Kitaev quantum-spin-liquid(QSL)candidates,α-RuCl_(3)has received a great deal of attention.However,its ground state exhibits a long-range zigzag magnetic order,which defies the QSL phase.Nevertheless,the magnetic order is fragile and can be completely suppressed by applying an external magnetic field.Here,we explore the evolution of magnetic excitations ofα-RuCl;under an in-plane magnetic field,by carrying out inelastic neutron scattering measurements on high-quality single crystals.Under zero field,there exist spin-wave excitations near the M point and a continuum near theΓpoint,which are believed to be associated with the zigzag magnetic order and fractional excitations of the Kitaev QSL state,respectively.By increasing the magnetic field,the spin-wave excitations gradually give way to the continuous excitations.On the verge of the critical fieldμ_(0)H_(c)=7.5 T,the former ones vanish and only the latter ones are left,indicating the emergence of a pure QSL state.By further increasing the field strength,the excitations near theΓpoint become more intense.By following the gap evolution of the excitations near theΓpoint,we are able to establish a phase diagram composed of three interesting phases,including a gapped zigzag order phase at low fields,possibly gapless QSL phase nearμ;H;,and gapped partially polarized phase at high fields.These results demonstrate that an in-plane magnetic field can driveα-RuCl;into a long-sought QSL state near the critical field.
基金This work was supported by the National Natural Science Foun-dation of China(22172063)the Young Taishan Scholar Pro-gram(tsqn201812080)+1 种基金the Natural Science Foundation of Shandong Province(ZR2019YQ10)the Independent Cultivation Program of Innovation Team of Jinan City(2021GXRC052).
文摘Thanks to the synergistic effect,the bimetallic catalysts show better catalytic activity than the single metal cat-alysts and become a focus of research in heterogeneous catalysis.In this study,we successfully prepared Pd-Pt icosahedra which show high peroxidase-like activity under the synergistic effects of Pd and Pt.V max of the Pd-Pt icosahedra was significantly enhanced by 1.66 times for 3,3’,5,5’-tetramethylbenzidine(TMB)as the substrate and 1.23 times for H_(2)O_(2) as the substrate,compared to that of the Pd icosahedra alone.By harnessing the supe-rior peroxidase-like activity of Pd-Pt icosahedra,we successfully utilized Pd-Pt icosahedral nanozymes in various biological analyses based on colorimetry.In most cases,using a Pd-Pt icosahedra/H_(2)O_(2)/TMB system,glucose,glutathione(GSH),acid phosphatase(ACP),and alkaline phosphatase(ALP)were detected over a wide range of 0.05∼0.20 mM,0∼20 mM,0∼10 U/L and 0∼12 U/L.In this study,we prepared a novel bimetallic nanozyme that exhibited excellent peroxidase-like activity owing to the bimetallic synergistic effect,thus demonstrating the promising potential of Pd-Pt icosahedra in the field of bioanalysis.