In the recent years,with rapid development of mobile internet,new media platform has been developing at full speed,such as twitter,WeC hat and APP. It has wide information dissemination channels,fast release frequency...In the recent years,with rapid development of mobile internet,new media platform has been developing at full speed,such as twitter,WeC hat and APP. It has wide information dissemination channels,fast release frequency and efficient interactive mode. According to the characteristics of new media,we set forth the current situation of public weather service. Through the questionnaire survey,we have analyzed the actual demand of public from three aspects,including the public reading habits,characteristics of sharing and transmission and defect of information distribution. Finally,we have discussed the future trend of meteorological new media,which will promote public service effectiveness of meteorological new media by considering requirement,applying new technology and reasonably using platform.展开更多
The interaction between mechanics and chemistry plays an essential and critical role in the behaviors and properties of materials,especially in nanoscale alloys. Based on the classical Gibbs and Mc Lean adsorption iso...The interaction between mechanics and chemistry plays an essential and critical role in the behaviors and properties of materials,especially in nanoscale alloys. Based on the classical Gibbs and Mc Lean adsorption isotherms, the present study takes the freestanding nanometer thick films of Pd-H solid solutions as a typic example to investigate surface segregation of hydrogen. The surface eigenstress model is further developed here to give analytic formulas, which have the capability to quantitatively predict the size-dependent surface segregation. Molecular dynamics(MD) simulations are conducted on free-standing Pd-H nanofilms.The MD simulations verify the theoretical analytic results and determine the values of parameters involved in the theoretical analysis. The integrated theoretical and numerical study exhibits that both surface excess H concentration and apparent biaxial Young’s modulus of Pd-H thin films depend on the nominal H concentration and the film thickness. The MD simulations determine the values of three parameters involved in the theoretical analysis. Especially, the parameter of the differentiation in reference chemical potential behaves like the molar free energy of segregation in the Mc Lean adsorption isotherm.展开更多
基金Supported by Soft Science Project of Beijing Meteorological Bureau[2017Y05]
文摘In the recent years,with rapid development of mobile internet,new media platform has been developing at full speed,such as twitter,WeC hat and APP. It has wide information dissemination channels,fast release frequency and efficient interactive mode. According to the characteristics of new media,we set forth the current situation of public weather service. Through the questionnaire survey,we have analyzed the actual demand of public from three aspects,including the public reading habits,characteristics of sharing and transmission and defect of information distribution. Finally,we have discussed the future trend of meteorological new media,which will promote public service effectiveness of meteorological new media by considering requirement,applying new technology and reasonably using platform.
基金supported by the National Key R&D Program of China(Grant No.2017YFB0701604)support by the National Natural Science Foundation of China(Grant No.11672168)
文摘The interaction between mechanics and chemistry plays an essential and critical role in the behaviors and properties of materials,especially in nanoscale alloys. Based on the classical Gibbs and Mc Lean adsorption isotherms, the present study takes the freestanding nanometer thick films of Pd-H solid solutions as a typic example to investigate surface segregation of hydrogen. The surface eigenstress model is further developed here to give analytic formulas, which have the capability to quantitatively predict the size-dependent surface segregation. Molecular dynamics(MD) simulations are conducted on free-standing Pd-H nanofilms.The MD simulations verify the theoretical analytic results and determine the values of parameters involved in the theoretical analysis. The integrated theoretical and numerical study exhibits that both surface excess H concentration and apparent biaxial Young’s modulus of Pd-H thin films depend on the nominal H concentration and the film thickness. The MD simulations determine the values of three parameters involved in the theoretical analysis. Especially, the parameter of the differentiation in reference chemical potential behaves like the molar free energy of segregation in the Mc Lean adsorption isotherm.
