The strength of the power frequency electric intensity and magnetic field of the 500-kV double circuit transmission lines was calculated by using the equivalent charge method and the Ampere's Law, and the environm...The strength of the power frequency electric intensity and magnetic field of the 500-kV double circuit transmission lines was calculated by using the equivalent charge method and the Ampere's Law, and the environmental impact factors of the fields were evaluated. By optimizing the phase sequence, the frequency electric intensity and magnetic field strength can be reduced. Within a distance of 25 m from the center of the transmission line, the power frequency electric intensity and magnetic field strength fall off sharply with the distance increase. Finally, the best phase sequence and the minimum ground clearance of the transmission lines were obtained to meet the requirements of the least impact on envionment.展开更多
We report thermodynamic and neutron scattering measurements of the triangular-lattice quantum Ising magnet TmMgGaO_(4)in longitudinal magnetic fields.Our experiments reveal a quasi-plateau state induced by quantum flu...We report thermodynamic and neutron scattering measurements of the triangular-lattice quantum Ising magnet TmMgGaO_(4)in longitudinal magnetic fields.Our experiments reveal a quasi-plateau state induced by quantum fluctuations.This state exhibits an unconventional non-monotonic field and temperature dependence of the magnetic order and excitation gap.In the high field regime where the quantum fluctuations are largely suppressed,we observed a disordered state with coherent magnon-like excitations despite the suppression of the spin excitation intensity.Through detailed semi-classical calculations,we are able to understand these behaviors quantitatively from the subtle competition between quantum fluctuations and frustrated Ising interactions.展开更多
Using a variational approach,the propagation of a moderately intense laser pulse in a parabolic preformed plasma channel is investigated.The effects of higher-order relativistic nonlinearity (HRN) and wakefield are in...Using a variational approach,the propagation of a moderately intense laser pulse in a parabolic preformed plasma channel is investigated.The effects of higher-order relativistic nonlinearity (HRN) and wakefield are included.The effect of HRN serves as an additional defocusing mechanism and has the same order of magnitude in the spot size as that of the transverse wakefield (TWF).The effect of longitudinal wakefield is much larger than those of HRN and TWF for an intense laser pulse with the pulse length equaling the plasma wavelength.The catastrophic focusing of the laser spot size would be prevented in the present of HRN and then it varies with periodic focusing oscillations.展开更多
文摘The strength of the power frequency electric intensity and magnetic field of the 500-kV double circuit transmission lines was calculated by using the equivalent charge method and the Ampere's Law, and the environmental impact factors of the fields were evaluated. By optimizing the phase sequence, the frequency electric intensity and magnetic field strength can be reduced. Within a distance of 25 m from the center of the transmission line, the power frequency electric intensity and magnetic field strength fall off sharply with the distance increase. Finally, the best phase sequence and the minimum ground clearance of the transmission lines were obtained to meet the requirements of the least impact on envionment.
基金supported by the Innovation Program of Shanghai Municipal Education Commission(2017–01-07–00-07-E00018)the National Key R&D Program of the MOST of China(2016YFA0300203,2016YFA0300500,2016YFA0301001,and 2018YFE0103200)+6 种基金the National Natural Science Foundation of China(11874119)Shanghai Municipal Science and Technology Major Project(2019SHZDZX04)the Hong Kong Research Grants Council(17303819 and 17306520)supported by the National Natural Science Foundation of China(11875265)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(3He based neutron polarization devices)the Institute of High Energy Physicsthe Chinese Academy of Sciences。
文摘We report thermodynamic and neutron scattering measurements of the triangular-lattice quantum Ising magnet TmMgGaO_(4)in longitudinal magnetic fields.Our experiments reveal a quasi-plateau state induced by quantum fluctuations.This state exhibits an unconventional non-monotonic field and temperature dependence of the magnetic order and excitation gap.In the high field regime where the quantum fluctuations are largely suppressed,we observed a disordered state with coherent magnon-like excitations despite the suppression of the spin excitation intensity.Through detailed semi-classical calculations,we are able to understand these behaviors quantitatively from the subtle competition between quantum fluctuations and frustrated Ising interactions.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11047152,11147005,and 11178002the Natural Science Foundation of Jiangxi Province under Grant Nos.2010GQW0048 and 20122BAB202003
文摘Using a variational approach,the propagation of a moderately intense laser pulse in a parabolic preformed plasma channel is investigated.The effects of higher-order relativistic nonlinearity (HRN) and wakefield are included.The effect of HRN serves as an additional defocusing mechanism and has the same order of magnitude in the spot size as that of the transverse wakefield (TWF).The effect of longitudinal wakefield is much larger than those of HRN and TWF for an intense laser pulse with the pulse length equaling the plasma wavelength.The catastrophic focusing of the laser spot size would be prevented in the present of HRN and then it varies with periodic focusing oscillations.
