Electrical emission (EM) signals, which are generated from the concrete specimens under three-point bending tests, were conducted. It is shown that electrical emission phenomena are related to cracking of the specimen...Electrical emission (EM) signals, which are generated from the concrete specimens under three-point bending tests, were conducted. It is shown that electrical emission phenomena are related to cracking of the specimens, cohesive failure, contact-separation etc. The simultaneous appearance of electric emission signals and visible cracks during the flexure loading of beams was also observed.展开更多
Electricity consumption is one of the major contributors to greenhouse gas emissions.In this study,we build a power consumption carbon emission measurement model based on the operating margin factor.We use the decompo...Electricity consumption is one of the major contributors to greenhouse gas emissions.In this study,we build a power consumption carbon emission measurement model based on the operating margin factor.We use the decomposition and decoupling technology of logarithmic mean Divisia index method to quantify six effects(emission intensity,power generation structure,consumption electricity intensity,economic scale,population structure,and population scale)and comprehensively reflect the degree of dependence of electricity consumption carbon emissions on China's economic development and population changes.Moreover,we utilize the decoupling model to analyze the decoupling state between carbon emissions and economic growth and identify corresponding energy efficiency policies.The results of this study provide a new perspective to understand carbon emission reduction potentials in the electricity use of China.展开更多
The authors presented a facile approach to prepare highly-ordered sub-micrometer scaled cylindrical diamond arrays based on a chemical vapor deposition method,where the accurate control of the style of crystal seeds d...The authors presented a facile approach to prepare highly-ordered sub-micrometer scaled cylindrical diamond arrays based on a chemical vapor deposition method,where the accurate control of the style of crystal seeds dispersion and the growth time are very crucial.The as-prepared diamond array showed good conductivity which was originated from the proper boron doping,and moreover,it exhibited good field emission property with low turn-on field and high emission current.Importantly,this approach can be easily applied to the preparation of various micro-patterned one-dimensional diamond arrays.展开更多
Liquid metal droplets are accelerated by electrostatic forces in a process known as field emission.In this study,we simulate the emission of charged indium droplets on a needle in 2D cylindrical coordinates.The bounda...Liquid metal droplets are accelerated by electrostatic forces in a process known as field emission.In this study,we simulate the emission of charged indium droplets on a needle in 2D cylindrical coordinates.The boundary element method is used to rapidly and accurately calculate the electric field on the fluid surface,which is then advected forward in time using level sets.This is the first time these methods have been combined,and this combination addresses difficult detachable surface tracking issues successfully.A histogram of droplet charge-to-mass ratio is generated in which it is predicted that smaller satellite droplets are more densely charged.In addition,our model is compared with independent pre-and post-snap off data and produces good agreement with the result.展开更多
文摘Electrical emission (EM) signals, which are generated from the concrete specimens under three-point bending tests, were conducted. It is shown that electrical emission phenomena are related to cracking of the specimens, cohesive failure, contact-separation etc. The simultaneous appearance of electric emission signals and visible cracks during the flexure loading of beams was also observed.
基金This study was sponsored by the National Natural Science Foundation of China(Grant No.72131001).
文摘Electricity consumption is one of the major contributors to greenhouse gas emissions.In this study,we build a power consumption carbon emission measurement model based on the operating margin factor.We use the decomposition and decoupling technology of logarithmic mean Divisia index method to quantify six effects(emission intensity,power generation structure,consumption electricity intensity,economic scale,population structure,and population scale)and comprehensively reflect the degree of dependence of electricity consumption carbon emissions on China's economic development and population changes.Moreover,we utilize the decoupling model to analyze the decoupling state between carbon emissions and economic growth and identify corresponding energy efficiency policies.The results of this study provide a new perspective to understand carbon emission reduction potentials in the electricity use of China.
基金Supported by the National Natural Science Foundation of China(Nos.20601005,20125102 and 20571077)the National Basic Research Program of China(Nos.2010CB934700,2009CB930404 and 2007CB936403)+1 种基金the Special Fund for Special Prize of the President Awardthe Chinese Postdoctoral Fund and K. C. Wong Education Foundation
文摘The authors presented a facile approach to prepare highly-ordered sub-micrometer scaled cylindrical diamond arrays based on a chemical vapor deposition method,where the accurate control of the style of crystal seeds dispersion and the growth time are very crucial.The as-prepared diamond array showed good conductivity which was originated from the proper boron doping,and moreover,it exhibited good field emission property with low turn-on field and high emission current.Importantly,this approach can be easily applied to the preparation of various micro-patterned one-dimensional diamond arrays.
基金supported in part by the NSF under contract DMS 0108672Christlieb’s work supported in part by the Air Force Office of Scientific Research(AFOSR)under Grant FA9550-05-1-0199.
文摘Liquid metal droplets are accelerated by electrostatic forces in a process known as field emission.In this study,we simulate the emission of charged indium droplets on a needle in 2D cylindrical coordinates.The boundary element method is used to rapidly and accurately calculate the electric field on the fluid surface,which is then advected forward in time using level sets.This is the first time these methods have been combined,and this combination addresses difficult detachable surface tracking issues successfully.A histogram of droplet charge-to-mass ratio is generated in which it is predicted that smaller satellite droplets are more densely charged.In addition,our model is compared with independent pre-and post-snap off data and produces good agreement with the result.
