Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting billets.Different from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimens...Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting billets.Different from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification defects.In this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring methods.Following a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 Hz.The higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of billet.The experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element segregation.The SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.展开更多
G-protein-coupled receptors(GPCRs)are the largest family of transmembrane receptors and regulate various physiological and pathological processes.Despite extensive studies,the roles of GPCRs in mouse embryonic stem ce...G-protein-coupled receptors(GPCRs)are the largest family of transmembrane receptors and regulate various physiological and pathological processes.Despite extensive studies,the roles of GPCRs in mouse embryonic stem cells(mESCs)remain poorly understood.Here,we show that GPR160,a class A member of GPCRs,is dramatically downregulated concurrent with mESC differentiation into embryoid bodies in vitro.Knockdown of Gpr160 leads to downregulation of the expression of pluripotency-associated transcription factors and upregulation of the expression of lineage markers,accompanying with the ar-rest of the mESC cell-cycle in the GO/G1 phase.RNA-seq analysis shows that GPR160 participates in the JAK/STAT signaling pathway crucial formaintaining ESC stemness,and the knockdown of Gpr160 results in the downregulation of STAT3 phosphorylation level,which in turn is partially rescued by colivelin,a STAT3 activator.Consistent with these observations,GPR160 physically interacts with JAK1,and co-operates with leukemia inhibitory factor receptor(LIFR)and gp130 to activate the STAT3 pathway.In summary,our results suggest that GPR160 regulates mESC self-renewal and pluripotency by interacting with the JAK1-LIFR-gp130 complex to mediate the JAK1/STAT3 signaling pathway.展开更多
A method was developed to quantitatively describe the time-varying Lorentz force field induced in billet under harmonic magnetic field.Based on the numerical analysis of the Lorentz force,the numeral features were con...A method was developed to quantitatively describe the time-varying Lorentz force field induced in billet under harmonic magnetic field.Based on the numerical analysis of the Lorentz force,the numeral features were concluded, which comprised of the mean force,the maximum force,the long axis,short axis and rotation direction of ellipse,the phase difference index,and so on.Using this method,the Lorentz force field in φ160 billet under 3 Hz harmonic magnetic field were analyzed.展开更多
基金financially supported by the National Key R&D Projects(No.2021YFB3702000)the Regional Company Projects in Ansteel Beijing Research Institute(No.2022BJB07GF&No.2022BJB-13GF)。
文摘Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting billets.Different from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification defects.In this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring methods.Following a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 Hz.The higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of billet.The experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element segregation.The SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.
基金This work was funded by grants from the National Key Research and Development Program of China(2019YFA0801402)the National Natural Science Foundation of China(82271890)+3 种基金the Shanghai Key Clinical Specialty Project(shslczdzk05705)the Shanghai Top Priority Key Discipline Project(2017zz02019)Innovative Research Team of High-Level Local Universities in Shanghai(SHSMU-ZDCX20212200)the Macao Science and Technology Development fund(FDCT)(0092/2022/A2 and 003/2022/ALC).
文摘G-protein-coupled receptors(GPCRs)are the largest family of transmembrane receptors and regulate various physiological and pathological processes.Despite extensive studies,the roles of GPCRs in mouse embryonic stem cells(mESCs)remain poorly understood.Here,we show that GPR160,a class A member of GPCRs,is dramatically downregulated concurrent with mESC differentiation into embryoid bodies in vitro.Knockdown of Gpr160 leads to downregulation of the expression of pluripotency-associated transcription factors and upregulation of the expression of lineage markers,accompanying with the ar-rest of the mESC cell-cycle in the GO/G1 phase.RNA-seq analysis shows that GPR160 participates in the JAK/STAT signaling pathway crucial formaintaining ESC stemness,and the knockdown of Gpr160 results in the downregulation of STAT3 phosphorylation level,which in turn is partially rescued by colivelin,a STAT3 activator.Consistent with these observations,GPR160 physically interacts with JAK1,and co-operates with leukemia inhibitory factor receptor(LIFR)and gp130 to activate the STAT3 pathway.In summary,our results suggest that GPR160 regulates mESC self-renewal and pluripotency by interacting with the JAK1-LIFR-gp130 complex to mediate the JAK1/STAT3 signaling pathway.
文摘A method was developed to quantitatively describe the time-varying Lorentz force field induced in billet under harmonic magnetic field.Based on the numerical analysis of the Lorentz force,the numeral features were concluded, which comprised of the mean force,the maximum force,the long axis,short axis and rotation direction of ellipse,the phase difference index,and so on.Using this method,the Lorentz force field in φ160 billet under 3 Hz harmonic magnetic field were analyzed.
