A thorny problem in the miscible Ti/Fe system is the unavoidable formation of numerous brittle intermetallic compounds(IMCs).Adding H62 interlayer is an essential method to reduce the brittle IMCs or decrease the brit...A thorny problem in the miscible Ti/Fe system is the unavoidable formation of numerous brittle intermetallic compounds(IMCs).Adding H62 interlayer is an essential method to reduce the brittle IMCs or decrease the brittleness.A joint with good formability and tensile properties was obtained.The microstructure and element distribution of the joint were observed by metallographic microscopy,scanning electron microscopy and electron probe microanalysis.The shear resistance exhibited an initial increase,followed by a subsequent decrease,with an increase in heat input.It reached a maximum value of 2470 N at a welding energy of 267 kJ/m.The Fe-Ti brittle IMCs in TC4/DP780 joints are replaced by Fe-Cu phase and Cu-Ti phase,which reduces the brittleness at TC4/DP780 interface.The results show that the TC4/DP780 joint forms numerousα-Cu andγ-Fe solid solutions through the mutual diffusion and solid solution between H62 and TC4 layers of metals,which effectively inhibits the diffusion of Ti atoms and reduces the formation of brittle Ti-Fe IMCs.At the H62/TC4 interface,a composite layer composed of Cu-Ti IMCs and Cu-based solid solutions is formed.The composite layer grows dendritically from the TC4 alloy to the H62 interlayer.The microstructure at the TC4/DP780 interface changes from fine dendrites to coarse dendrites with the increase in Ti content and heat input.When the heat input is lower,the interfacial elements do not react sufficiently.When the heat input is excessive,microcracks appear at the TC4/DP780 interface,which limits the improvement of mechanical properties of TC4/DP780 joint.展开更多
The hydrophobic sonosensitizer IR780 iodide(IR780)was loaded into liposomes to form Liposome@IR780 nanoparticles(NPs)for triple-negative breast cancer(TNBC)to enhance SDT via low-intensity ultrasound(LIU)irradiation.T...The hydrophobic sonosensitizer IR780 iodide(IR780)was loaded into liposomes to form Liposome@IR780 nanoparticles(NPs)for triple-negative breast cancer(TNBC)to enhance SDT via low-intensity ultrasound(LIU)irradiation.The NPs were characterized using various physicochemical methods including size distribution,zeta potential,and morphology.In vitro experiments show that the Liposome@IR780 NPs can generate more reactive oxygen species(ROS)upon LIU irradiation.The apoptosis experiment results further demonstrate that Liposome@IR780 NPs show better apoptosis rate against 4T1 cells.Our results indicate that Liposome@IR780 NPs will provide a promising approach for TNBC upon SDT treatment.展开更多
This study deals with the development of a 780-MPa-class hot-rolled advanced high-strength steel(AHSS)with an ultrahigh elongation at break of approximately 30%and strength-ductility product exceeding 24 GPa·%,in...This study deals with the development of a 780-MPa-class hot-rolled advanced high-strength steel(AHSS)with an ultrahigh elongation at break of approximately 30%and strength-ductility product exceeding 24 GPa·%,indicating the excellent formability of the newly developed AHSS.The microstructure of the newly developed 780-MPa-class AHSS consists mainly of the triplex phase of ferrite,bainite,and retained austenite with a volume fraction of 10%±2%.The stability of the retained austenite in the newly developed AHSS is much higher than that of conventional transformation-induced plasticity steels,in which the retained austenite is prone to transformation into martensite under deformation.At a pre-strain lower than 1.2%,the volume fraction of the retained austenite and the elongation at break of the present 780-MPa-class AHSS remain almost unchanged,showing a high tolerance in the process window during leveling or straightening.Therefore,the present 780-MPa-class AHSS is particularly suitable for the production of components with complex shapes.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.52001141 and 52475360).
文摘A thorny problem in the miscible Ti/Fe system is the unavoidable formation of numerous brittle intermetallic compounds(IMCs).Adding H62 interlayer is an essential method to reduce the brittle IMCs or decrease the brittleness.A joint with good formability and tensile properties was obtained.The microstructure and element distribution of the joint were observed by metallographic microscopy,scanning electron microscopy and electron probe microanalysis.The shear resistance exhibited an initial increase,followed by a subsequent decrease,with an increase in heat input.It reached a maximum value of 2470 N at a welding energy of 267 kJ/m.The Fe-Ti brittle IMCs in TC4/DP780 joints are replaced by Fe-Cu phase and Cu-Ti phase,which reduces the brittleness at TC4/DP780 interface.The results show that the TC4/DP780 joint forms numerousα-Cu andγ-Fe solid solutions through the mutual diffusion and solid solution between H62 and TC4 layers of metals,which effectively inhibits the diffusion of Ti atoms and reduces the formation of brittle Ti-Fe IMCs.At the H62/TC4 interface,a composite layer composed of Cu-Ti IMCs and Cu-based solid solutions is formed.The composite layer grows dendritically from the TC4 alloy to the H62 interlayer.The microstructure at the TC4/DP780 interface changes from fine dendrites to coarse dendrites with the increase in Ti content and heat input.When the heat input is lower,the interfacial elements do not react sufficiently.When the heat input is excessive,microcracks appear at the TC4/DP780 interface,which limits the improvement of mechanical properties of TC4/DP780 joint.
文摘The hydrophobic sonosensitizer IR780 iodide(IR780)was loaded into liposomes to form Liposome@IR780 nanoparticles(NPs)for triple-negative breast cancer(TNBC)to enhance SDT via low-intensity ultrasound(LIU)irradiation.The NPs were characterized using various physicochemical methods including size distribution,zeta potential,and morphology.In vitro experiments show that the Liposome@IR780 NPs can generate more reactive oxygen species(ROS)upon LIU irradiation.The apoptosis experiment results further demonstrate that Liposome@IR780 NPs show better apoptosis rate against 4T1 cells.Our results indicate that Liposome@IR780 NPs will provide a promising approach for TNBC upon SDT treatment.
文摘This study deals with the development of a 780-MPa-class hot-rolled advanced high-strength steel(AHSS)with an ultrahigh elongation at break of approximately 30%and strength-ductility product exceeding 24 GPa·%,indicating the excellent formability of the newly developed AHSS.The microstructure of the newly developed 780-MPa-class AHSS consists mainly of the triplex phase of ferrite,bainite,and retained austenite with a volume fraction of 10%±2%.The stability of the retained austenite in the newly developed AHSS is much higher than that of conventional transformation-induced plasticity steels,in which the retained austenite is prone to transformation into martensite under deformation.At a pre-strain lower than 1.2%,the volume fraction of the retained austenite and the elongation at break of the present 780-MPa-class AHSS remain almost unchanged,showing a high tolerance in the process window during leveling or straightening.Therefore,the present 780-MPa-class AHSS is particularly suitable for the production of components with complex shapes.