By means of maximum principle for nonlinear hyperbolic systems, the results given by HSIAO Ling and D. Serre was improved for Cauchy problem of compressible adiabatic flow through porous media, and a complete result o...By means of maximum principle for nonlinear hyperbolic systems, the results given by HSIAO Ling and D. Serre was improved for Cauchy problem of compressible adiabatic flow through porous media, and a complete result on the global existence and the blow-up phenomena of classical solutions of these systems. These results show that the dissipation is strong enough to preserve the smoothness of ‘small ’ solution.展开更多
Since social media increasingly infiltrates the workplace,it may affect employee innovation.However,how so-cial media use(SMU)affects employee innovation performance remains controversial.Therefore,this study explores...Since social media increasingly infiltrates the workplace,it may affect employee innovation.However,how so-cial media use(SMU)affects employee innovation performance remains controversial.Therefore,this study explores the underlying mechanisms and boundary conditions in the relationship between SMU and employee innovation performance.The research model was tested through a survey of 221 Chinese employees.The results show that SMU is positively re-lated to employee innovation performance,with work engagement acting as a mediator in this relationship.Employee tra-ditionality positively moderates the positive impact of work-related SMU on work engagement,while traditionality has no moderating effect on the relationship between social-related SMU and work engagement.This study focuses on the rela-tionship between SMU and innovation performance based on conservation of resources theory,offering insights into the intrinsic mechanism by which SMU affects employee innovation.Furthermore,this study considers the moderating effect of employee traditionality based on social cognitive theory,enriching the knowledge of how traditionality influences the impacts of SMU.This study has theoretical implications for future research and practical guidance for enterprises regard-ing the proper use of social media.展开更多
2024年10月,Lancet与JAMA分别发表了关于社交媒体对青少年精神健康影响的社论——《Unhealthy influencers?Social Media and Youth Mental Health》和《Social Media and Suicide Risk in Youth》。文章指出,在过去15年,随着社交媒体...2024年10月,Lancet与JAMA分别发表了关于社交媒体对青少年精神健康影响的社论——《Unhealthy influencers?Social Media and Youth Mental Health》和《Social Media and Suicide Risk in Youth》。文章指出,在过去15年,随着社交媒体使用频率的增加,10~24岁人群的精神疾病患病率及自我伤害行为出现显著增长的现象。展开更多
A strategy for the green synthesis of heterocyclicβ-ketosulfides via nucleophilic substitution ofα-halogenated ketone with het-eroaryl thiols in water media is presented.Compared with the available literature report...A strategy for the green synthesis of heterocyclicβ-ketosulfides via nucleophilic substitution ofα-halogenated ketone with het-eroaryl thiols in water media is presented.Compared with the available literature reports,this new method had the advantages of base-free,additives-free,simple operation,mild condition,greenness,high efficiency,tolerance of a broad scope of substrates.Furth-more,the reaction could easily be scaled up in gram scale and the products also could easily transformed to other useful organic compounds.Mechanism investigation indicated that the tautomerism of pyrimidine-2-thiol to pyrimidine-2(1H)-thione and the hy-drogen bonds played important roles in the reaction.展开更多
Following the fundamental characteristics of the porosity windbreak,this study suggests a new numerical investigation method for the wind field of the windbreak based on the porous medium physical model.This method ca...Following the fundamental characteristics of the porosity windbreak,this study suggests a new numerical investigation method for the wind field of the windbreak based on the porous medium physical model.This method can transform the reasonable matching problem of the porosity and windproof performance of the windbreak into a study of the relationship between the resistance coefficient of the porous medium and the aerodynamic load of the train.This study examines the influence of the hole type on the wind field behind the porosity windbreak.Then,the relationship between the resistance coefficient of the porous medium,the porosity of the windbreak,and the aerodynamic loads of the train is investigated.The results show that the porous media physical model can be used instead of the windbreak geometry to study the windbreak-train aerodynamic performance,and the process of using this method is suggested.展开更多
文摘By means of maximum principle for nonlinear hyperbolic systems, the results given by HSIAO Ling and D. Serre was improved for Cauchy problem of compressible adiabatic flow through porous media, and a complete result on the global existence and the blow-up phenomena of classical solutions of these systems. These results show that the dissipation is strong enough to preserve the smoothness of ‘small ’ solution.
基金supported by the National Natural Science Foundation of China(72332007)。
文摘Since social media increasingly infiltrates the workplace,it may affect employee innovation.However,how so-cial media use(SMU)affects employee innovation performance remains controversial.Therefore,this study explores the underlying mechanisms and boundary conditions in the relationship between SMU and employee innovation performance.The research model was tested through a survey of 221 Chinese employees.The results show that SMU is positively re-lated to employee innovation performance,with work engagement acting as a mediator in this relationship.Employee tra-ditionality positively moderates the positive impact of work-related SMU on work engagement,while traditionality has no moderating effect on the relationship between social-related SMU and work engagement.This study focuses on the rela-tionship between SMU and innovation performance based on conservation of resources theory,offering insights into the intrinsic mechanism by which SMU affects employee innovation.Furthermore,this study considers the moderating effect of employee traditionality based on social cognitive theory,enriching the knowledge of how traditionality influences the impacts of SMU.This study has theoretical implications for future research and practical guidance for enterprises regard-ing the proper use of social media.
文摘2024年10月,Lancet与JAMA分别发表了关于社交媒体对青少年精神健康影响的社论——《Unhealthy influencers?Social Media and Youth Mental Health》和《Social Media and Suicide Risk in Youth》。文章指出,在过去15年,随着社交媒体使用频率的增加,10~24岁人群的精神疾病患病率及自我伤害行为出现显著增长的现象。
文摘A strategy for the green synthesis of heterocyclicβ-ketosulfides via nucleophilic substitution ofα-halogenated ketone with het-eroaryl thiols in water media is presented.Compared with the available literature reports,this new method had the advantages of base-free,additives-free,simple operation,mild condition,greenness,high efficiency,tolerance of a broad scope of substrates.Furth-more,the reaction could easily be scaled up in gram scale and the products also could easily transformed to other useful organic compounds.Mechanism investigation indicated that the tautomerism of pyrimidine-2-thiol to pyrimidine-2(1H)-thione and the hy-drogen bonds played important roles in the reaction.
基金Projects(52302447,52388102,52372369)supported by the National Natural Science Foundation of China。
文摘Following the fundamental characteristics of the porosity windbreak,this study suggests a new numerical investigation method for the wind field of the windbreak based on the porous medium physical model.This method can transform the reasonable matching problem of the porosity and windproof performance of the windbreak into a study of the relationship between the resistance coefficient of the porous medium and the aerodynamic load of the train.This study examines the influence of the hole type on the wind field behind the porosity windbreak.Then,the relationship between the resistance coefficient of the porous medium,the porosity of the windbreak,and the aerodynamic loads of the train is investigated.The results show that the porous media physical model can be used instead of the windbreak geometry to study the windbreak-train aerodynamic performance,and the process of using this method is suggested.
