Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O soluti...Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.展开更多
International Chinese teachers are one of the determinants of the quality development of Confucius Institutes,and their cross-cultural sociocultural adaption,psychological adaption,and job adaption are in need of in-d...International Chinese teachers are one of the determinants of the quality development of Confucius Institutes,and their cross-cultural sociocultural adaption,psychological adaption,and job adaption are in need of in-depth investigation and research.Based on previous research,this paper analyzed the cross-cultural adaptation of international Chinese teachers at Confucius Institutes in South Korea during 2022-2023 through surveys and personal interviews.The study found that the teachers’adaptation was best in terms of work,followed by sociocultural adaptation,and weakest in terms of psychological adaptation.In terms of work adaptation,attention should be focused on adapting to teaching language and teaching methods.In terms of sociocultural adaptation,the focus should be on adapting to personal communication.In terms of psychological adaptation,attention should be paid to feelings of loneliness and anxiety.The study also focused on the internal and external factors influencing their cross-cultural adaptation,as well as the true inner feelings of international Chinese teachers.The study found that factors such as English proficiency,gender,education,professional background,and overseas experience had little impact on teachers’cross-cultural adaptation,while factors such as Korean proficiency,participation in cross-cultural training before going to South Korea,understanding of Korean culture before going to South Korea,and length of time spent in working in South Korea had a greater impact on the cross-cultural adaptation of the research subjects.This study provides reliable reference materials for international Chinese teachers going to South Korea to improve their cross-cultural adaptation abilities and promote the reform and innovation of international Chinese education.展开更多
The fracture theory of cubic quasicrystal was developed. The exact analytic solution of a Mode Ⅲ Griffith crack in the material was obtained by using the Fourier transform and dual integral equations theory, and so t...The fracture theory of cubic quasicrystal was developed. The exact analytic solution of a Mode Ⅲ Griffith crack in the material was obtained by using the Fourier transform and dual integral equations theory, and so the displacement and stress fields, the stress intensity factor and strain energy release rate were determined. The results show that the stress intensity factor is independent of material constants, and the strain energy release rate is dependent on all material constants. These provide important information for studying the deformation and fracture of the new solid material.展开更多
As the most intuitive way of visual signal feedback,color change is often applied by living organisms to transmit signals and resist natural enemies due to its convenient and direct characteristics.Inspired by the str...As the most intuitive way of visual signal feedback,color change is often applied by living organisms to transmit signals and resist natural enemies due to its convenient and direct characteristics.Inspired by the structure color charge of discoloration of chameleons skin,a photonic hydrogel film that can be used for flexible strain detection was developed.Fe_(3)O_(4)@C nanoparticles were used as photonic crystal units,which could self-assemble into one-dimensional chain-like structure in the hydrogel under magnetic field.The structural color of the film will change with the photonic crystal band gap,the film will produce a synergistic color change under mechanical stretching.The resulting flexible film demonstrates bright structural colors,which exhibits a wide strain response up to 120%and achieves a color dynamic change from red(λ=730 nm)to purple(λ=400 nm).In addition,the prepared film exhibits high sensitivity,short response time and good stabilization.The superior performance of flexible strain detection is attributed to the flexible large deformation and good optical properties of the hydrogel film and highly tunable grating structure of the photonic crystal.This work offers a generic approach for the development of visually responsive strain sensors,and provides a wider application prospect in mechanical sensors,stretchable optics,and diagnostics.展开更多
Based on the finite element method, a numerical investigation into the bonded repair efficiency of cracked plates under in plane biaxial loadings is presented. The main considerations are: reduction in stress intensi...Based on the finite element method, a numerical investigation into the bonded repair efficiency of cracked plates under in plane biaxial loadings is presented. The main considerations are: reduction in stress intensity factor (SIF) at the crack tip, the maximum tensile stress in the composite patch and the maximum shear stress in the adhesive bond between the patch and the plate. Without the patch, a tensile or compressive stress parallel to the crack has no effect on the SIF at the crack tip. While with a composite patch, there exists coupling effect between the normal stress parallel to the crack and the SIF, and the coupling effect depends significantly on ply orientation of the patch and the biaxial stress ratio of the plate.展开更多
文摘Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.
文摘International Chinese teachers are one of the determinants of the quality development of Confucius Institutes,and their cross-cultural sociocultural adaption,psychological adaption,and job adaption are in need of in-depth investigation and research.Based on previous research,this paper analyzed the cross-cultural adaptation of international Chinese teachers at Confucius Institutes in South Korea during 2022-2023 through surveys and personal interviews.The study found that the teachers’adaptation was best in terms of work,followed by sociocultural adaptation,and weakest in terms of psychological adaptation.In terms of work adaptation,attention should be focused on adapting to teaching language and teaching methods.In terms of sociocultural adaptation,the focus should be on adapting to personal communication.In terms of psychological adaptation,attention should be paid to feelings of loneliness and anxiety.The study also focused on the internal and external factors influencing their cross-cultural adaptation,as well as the true inner feelings of international Chinese teachers.The study found that factors such as English proficiency,gender,education,professional background,and overseas experience had little impact on teachers’cross-cultural adaptation,while factors such as Korean proficiency,participation in cross-cultural training before going to South Korea,understanding of Korean culture before going to South Korea,and length of time spent in working in South Korea had a greater impact on the cross-cultural adaptation of the research subjects.This study provides reliable reference materials for international Chinese teachers going to South Korea to improve their cross-cultural adaptation abilities and promote the reform and innovation of international Chinese education.
文摘The fracture theory of cubic quasicrystal was developed. The exact analytic solution of a Mode Ⅲ Griffith crack in the material was obtained by using the Fourier transform and dual integral equations theory, and so the displacement and stress fields, the stress intensity factor and strain energy release rate were determined. The results show that the stress intensity factor is independent of material constants, and the strain energy release rate is dependent on all material constants. These provide important information for studying the deformation and fracture of the new solid material.
文摘As the most intuitive way of visual signal feedback,color change is often applied by living organisms to transmit signals and resist natural enemies due to its convenient and direct characteristics.Inspired by the structure color charge of discoloration of chameleons skin,a photonic hydrogel film that can be used for flexible strain detection was developed.Fe_(3)O_(4)@C nanoparticles were used as photonic crystal units,which could self-assemble into one-dimensional chain-like structure in the hydrogel under magnetic field.The structural color of the film will change with the photonic crystal band gap,the film will produce a synergistic color change under mechanical stretching.The resulting flexible film demonstrates bright structural colors,which exhibits a wide strain response up to 120%and achieves a color dynamic change from red(λ=730 nm)to purple(λ=400 nm).In addition,the prepared film exhibits high sensitivity,short response time and good stabilization.The superior performance of flexible strain detection is attributed to the flexible large deformation and good optical properties of the hydrogel film and highly tunable grating structure of the photonic crystal.This work offers a generic approach for the development of visually responsive strain sensors,and provides a wider application prospect in mechanical sensors,stretchable optics,and diagnostics.
文摘Based on the finite element method, a numerical investigation into the bonded repair efficiency of cracked plates under in plane biaxial loadings is presented. The main considerations are: reduction in stress intensity factor (SIF) at the crack tip, the maximum tensile stress in the composite patch and the maximum shear stress in the adhesive bond between the patch and the plate. Without the patch, a tensile or compressive stress parallel to the crack has no effect on the SIF at the crack tip. While with a composite patch, there exists coupling effect between the normal stress parallel to the crack and the SIF, and the coupling effect depends significantly on ply orientation of the patch and the biaxial stress ratio of the plate.
