When relative motion occurs between a liquid and a solid, the two phases carry electric charge with opposite signs. The created charge easily accumulates in the liquid, and the amount of the charge carried in an insul...When relative motion occurs between a liquid and a solid, the two phases carry electric charge with opposite signs. The created charge easily accumulates in the liquid, and the amount of the charge carried in an insulated liquid refers to many factors, such as contact area with the solid surface, the contact time, and so forth. However, current theories agree that the amount of charge created during flow electrification is proportional to the contact surface. In this paper, the classical wall current theory is applied to establish an interfacial electrical double-layer model of flow electrification phenomena when an insulated liquid passes over metal pipe surface. Meanwhile, in conjunction with charge relaxation function, the relation between the charge density and flow velocity, the contact time and the contact area is obtained during the liquid flowing process. The experimental result demonstrates that the flowing charge carried in the insulated liquid is not simply proportional to the contact area, but has a non-linear dependence on the contact area and the contact time. Moreover, down flow experimental equipment pipes of different length and diameter, and dielectric hydraulic oil VG46 are used in an experimental study of laminar flow, in order to understand electrification phenomena in dielectric liquid flowing over metal pipes of different length and aperture. If they both increase linearly, charge relaxation will increase exponentially. As a result, the test result verifies related theoretical analysis, and the method given provides a theoretical basis to analyze interracial electrical phenomena.展开更多
Photon emission during contact electrification(CE)has recently been observed,which is called as CE-induced interface photon emission spectroscopy(CEIIPES).Physical mechanisms of CEIIPES are essential for interpreting ...Photon emission during contact electrification(CE)has recently been observed,which is called as CE-induced interface photon emission spectroscopy(CEIIPES).Physical mechanisms of CEIIPES are essential for interpreting the structure and electronic interactions of a contacted interface.Using the methods of density functional theory(DFT)and time-dependent DFT(TDDFT),it is confirmed theoretically that the spectrum of emitted photons is contributed from electron transfer and transition during CE.Specifically,the excited electrons from higher energy state in one material may transfer to a lower energy state of another material followed by a transition;and/or some unstable excited electrons at a higher energy level of one material may transit to a lower energy state of itself,both of which result in CEIIPES.Furthermore,the CE-induced interface absorption spectrum(CEIIAS)has been demonstrated,due to the intermolecular electron transfer excitation.展开更多
针对江铜贵冶电解车间 ISA 法残极大量断落所遇到的问题,结合生产实际操作,了解 ISA 法电解所需阳极板的工艺要求,铜电解的原理以及铜电解过程中电流强度大小、通电时间长短、电解过程中电解液液位停留的时间长短对残极断落的影响,总结...针对江铜贵冶电解车间 ISA 法残极大量断落所遇到的问题,结合生产实际操作,了解 ISA 法电解所需阳极板的工艺要求,铜电解的原理以及铜电解过程中电流强度大小、通电时间长短、电解过程中电解液液位停留的时间长短对残极断落的影响,总结造成残极断落的主要原因并针对原因提出了解决方案,从而保证了系统生产的稳定运行。展开更多
基金supported by Qianjiang Talent Project Foundation of China(Grant No. 2010R10013)
文摘When relative motion occurs between a liquid and a solid, the two phases carry electric charge with opposite signs. The created charge easily accumulates in the liquid, and the amount of the charge carried in an insulated liquid refers to many factors, such as contact area with the solid surface, the contact time, and so forth. However, current theories agree that the amount of charge created during flow electrification is proportional to the contact surface. In this paper, the classical wall current theory is applied to establish an interfacial electrical double-layer model of flow electrification phenomena when an insulated liquid passes over metal pipe surface. Meanwhile, in conjunction with charge relaxation function, the relation between the charge density and flow velocity, the contact time and the contact area is obtained during the liquid flowing process. The experimental result demonstrates that the flowing charge carried in the insulated liquid is not simply proportional to the contact area, but has a non-linear dependence on the contact area and the contact time. Moreover, down flow experimental equipment pipes of different length and diameter, and dielectric hydraulic oil VG46 are used in an experimental study of laminar flow, in order to understand electrification phenomena in dielectric liquid flowing over metal pipes of different length and aperture. If they both increase linearly, charge relaxation will increase exponentially. As a result, the test result verifies related theoretical analysis, and the method given provides a theoretical basis to analyze interracial electrical phenomena.
基金supported by the National Natural Science Foundation of China(Nos.62001031,52192610,51702018,and 51432005)the Youth Innovation Promotion Association,CAS,the Fundamental Research Funds for the Central Universities(No.E0E48957)the National Key R&D Program from Minister of Science and Technology(No.2016YFA0202704).
文摘Photon emission during contact electrification(CE)has recently been observed,which is called as CE-induced interface photon emission spectroscopy(CEIIPES).Physical mechanisms of CEIIPES are essential for interpreting the structure and electronic interactions of a contacted interface.Using the methods of density functional theory(DFT)and time-dependent DFT(TDDFT),it is confirmed theoretically that the spectrum of emitted photons is contributed from electron transfer and transition during CE.Specifically,the excited electrons from higher energy state in one material may transfer to a lower energy state of another material followed by a transition;and/or some unstable excited electrons at a higher energy level of one material may transit to a lower energy state of itself,both of which result in CEIIPES.Furthermore,the CE-induced interface absorption spectrum(CEIIAS)has been demonstrated,due to the intermolecular electron transfer excitation.
文摘针对江铜贵冶电解车间 ISA 法残极大量断落所遇到的问题,结合生产实际操作,了解 ISA 法电解所需阳极板的工艺要求,铜电解的原理以及铜电解过程中电流强度大小、通电时间长短、电解过程中电解液液位停留的时间长短对残极断落的影响,总结造成残极断落的主要原因并针对原因提出了解决方案,从而保证了系统生产的稳定运行。
