The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the...The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k×2k EUV CMOS imaging camera and to take full-disk solar images at the Ne VII 46.5 nm spectral line with a filter width of~3 nm.SUTRI employs a Ritchey-Chrétien optical system with an aperture of 18 cm.The on-orbit observations show that SUTRI images have a field of view of~416×416 and a moderate spatial resolution of~8″without an image stabilization system.The normal cadence of SUTRI images is 30 s and the solar observation time is about16 hr each day because the earth eclipse time accounts for about 1/3 of SATech-01's orbit period.Approximately15 GB data is acquired each day and made available online after processing.SUTRI images are valuable as the Ne VII 46.5 nm line is formed at a temperature regime of~0.5 MK in the solar atmosphere,which has rarely been sampled by existing solar imagers.SUTRI observations will establish connections between structures in the lower solar atmosphere and corona,and advance our understanding of various types of solar activity such as flares,filament eruptions,coronal jets and coronal mass ejections.展开更多
The nonlinear analyses of the hypersonic and high-enthalpy boundary-layer transition had received little attention compared with the widely-studied linear instabilities.In this work,the oblique-mode breakdown,as one o...The nonlinear analyses of the hypersonic and high-enthalpy boundary-layer transition had received little attention compared with the widely-studied linear instabilities.In this work,the oblique-mode breakdown,as one of the most available transition mechanisms,is studied using the nonlinear parabolized stability equations(NPSE)with consideration of the thermal-chemical non-equilibrium effects.The flow over a blunt cone is computed at a free-stream Mach-number of 15.The rope-like structures and the spontaneous radiation of sound waves are observed in the schlieren-like picture.It is also illustrated that the disturbances of the species mass and vibrational temperature near the wall are mainly generated by the product term of the wall-normal velocity disturbance and the mean-flow gradient.In comparison to the CPG flow,the TCNE effects destabilize the second mode and push upstream the N factor envelope.The higher growth rate of the oblique wave leads to stronger growth of the streamwise vortices and harmonic waves.展开更多
The effects of Cl^(-),Cu^(2+)and Fe^(3+)ions and their combinations on the corrosion behaviour of aluminium alloy 6063(AA6063)in ethylene glycol and water solutions at 50°C were investigated by electrochemical an...The effects of Cl^(-),Cu^(2+)and Fe^(3+)ions and their combinations on the corrosion behaviour of aluminium alloy 6063(AA6063)in ethylene glycol and water solutions at 50°C were investigated by electrochemical and immersion methods.Cl^(-)resulted in pitting corrosion of the alloy.In the Cl^(-)-free solutions,Fe^(3+)was prone to accelerate uniform corrosion,while Cu^(2+)tended to accelerate pitting corrosion.Severe pitting corrosion of AA6063 was observed in the cases of Cl^(-)combined with Cu^(2+)or Fe^(3+),especially in the case of Cl^(-)combined with Cu^(2+)and Fe^(3+)ions.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)under Grants 11825301,12003016,12073077the National Key R&D Program of China No.2021YFA0718600+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences with the Grant No.XDA15018400the Youth Innovation Promotion Association of CAS(2023061)。
文摘The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k×2k EUV CMOS imaging camera and to take full-disk solar images at the Ne VII 46.5 nm spectral line with a filter width of~3 nm.SUTRI employs a Ritchey-Chrétien optical system with an aperture of 18 cm.The on-orbit observations show that SUTRI images have a field of view of~416×416 and a moderate spatial resolution of~8″without an image stabilization system.The normal cadence of SUTRI images is 30 s and the solar observation time is about16 hr each day because the earth eclipse time accounts for about 1/3 of SATech-01's orbit period.Approximately15 GB data is acquired each day and made available online after processing.SUTRI images are valuable as the Ne VII 46.5 nm line is formed at a temperature regime of~0.5 MK in the solar atmosphere,which has rarely been sampled by existing solar imagers.SUTRI observations will establish connections between structures in the lower solar atmosphere and corona,and advance our understanding of various types of solar activity such as flares,filament eruptions,coronal jets and coronal mass ejections.
基金supported by the National Numerical Wind-tunnel projectThe authors also gratefully acknowledge the financial support of the National Key Research and Development Plan of China through the project No.2019YFA0405201the National Key Project(Grant No.GJXM92579).
文摘The nonlinear analyses of the hypersonic and high-enthalpy boundary-layer transition had received little attention compared with the widely-studied linear instabilities.In this work,the oblique-mode breakdown,as one of the most available transition mechanisms,is studied using the nonlinear parabolized stability equations(NPSE)with consideration of the thermal-chemical non-equilibrium effects.The flow over a blunt cone is computed at a free-stream Mach-number of 15.The rope-like structures and the spontaneous radiation of sound waves are observed in the schlieren-like picture.It is also illustrated that the disturbances of the species mass and vibrational temperature near the wall are mainly generated by the product term of the wall-normal velocity disturbance and the mean-flow gradient.In comparison to the CPG flow,the TCNE effects destabilize the second mode and push upstream the N factor envelope.The higher growth rate of the oblique wave leads to stronger growth of the streamwise vortices and harmonic waves.
基金financially supported by the National Natural Science Foundation of China(No.51531007)the Basic Research and Strategic Reserve Technology Research Fund(project of CNPC)(2020D-5008(2020Z-07))the Major Science and Technology Project of CNPC(2019D-2311)。
文摘The effects of Cl^(-),Cu^(2+)and Fe^(3+)ions and their combinations on the corrosion behaviour of aluminium alloy 6063(AA6063)in ethylene glycol and water solutions at 50°C were investigated by electrochemical and immersion methods.Cl^(-)resulted in pitting corrosion of the alloy.In the Cl^(-)-free solutions,Fe^(3+)was prone to accelerate uniform corrosion,while Cu^(2+)tended to accelerate pitting corrosion.Severe pitting corrosion of AA6063 was observed in the cases of Cl^(-)combined with Cu^(2+)or Fe^(3+),especially in the case of Cl^(-)combined with Cu^(2+)and Fe^(3+)ions.
