The hot deformation behaviors of as-solution Mg?xZn?yEr alloys (x/y=6, x=3.0, 4.5 and 6.0; y=0.50, 0.75 and 1.00) wereinvestigated on Gleeble?1500 thermal simulator in a temperature range of 200?450 °C at a strai...The hot deformation behaviors of as-solution Mg?xZn?yEr alloys (x/y=6, x=3.0, 4.5 and 6.0; y=0.50, 0.75 and 1.00) wereinvestigated on Gleeble?1500 thermal simulator in a temperature range of 200?450 °C at a strain rate of 0.001?1 s?1. The truestress?strain curves showed the dynamic competition between the working hardening and working softening mainly due to thedynamic recrystallization (DRX) occurring during hot compression. The constitutive equations were constructed which couldaccurately predict the peak stress of the alloys. The addition of Zn and/or Er resulted in higher deformation activation energy forMg?3Zn?0.5Er (alloy A). The processing maps were constructed as function of the temperature and the strain rate, providing theoptimum hot working conditions (i.e., at strain of 0.3, Mg?3Zn?0.5Er (alloy A): 380?430 ?C, <0.1 s?1; Mg?4.5Zn?0.75Er (alloy B):380?450 ?C, 0.01?0.1 s?1; Mg?6Zn?1Er (alloy C): 390?440 ?C, 0.01?0.1 s?1). The as-solution treated Mg?4.5Zn?0.75Er (alloy B)demonstrated more optimum hot working window comparing with Mg?3Zn?0.5Er (alloy A) and Mg?6Zn?1Er (alloy C).展开更多
The microstructure and texture evolutions in Mg-Zn-Er alloy during hot compression were investigated by using opticalmicroscope （OM）, field emission scanning electron microscope （EBSD） and transmission electron mi...The microstructure and texture evolutions in Mg-Zn-Er alloy during hot compression were investigated by using opticalmicroscope （OM）, field emission scanning electron microscope （EBSD） and transmission electron microscope （TEM）. The resultsindicate that the temperature plays an important role in dynamic recrystallization （DRX） mechanism. The twin dynamicrecrystallization （TDRX） is induced at a strain of 0.6 because of the activation of non-basal slip （a＋c ） dislocations at 200 ℃.Meanwhile, the continuous DRX （CDRX） occurs at 350℃, which is identified by the typical necklace-like structure around theresidual initial grains. The DRX contributes to the modification of texture significantly. The tension twins are responsible for theweak texture at 200 ℃. Meanwhile, the decrease in the basal texture is ascribed to the DRX sites which transfer from twinboundaries to initial grain boundaries as the temperature is increased from 200 to 350 ℃.展开更多
The synergistic effects of 2′-Fucosyllactose(2′-FL)or galactooligosaccharide(GOS)with Bifidobacterium bifidum DNG6(DNG6)attenuating dextran sulfate sodium(DSS)-induced colitis in mice were investigated.The results s...The synergistic effects of 2′-Fucosyllactose(2′-FL)or galactooligosaccharide(GOS)with Bifidobacterium bifidum DNG6(DNG6)attenuating dextran sulfate sodium(DSS)-induced colitis in mice were investigated.The results showed that DNG6,2′-FL and GOS alone or in combination could effectively prevent and improve symptoms of colitis.Among them,2′-FL and DNG6(2′-FL-DNG6)demonstrated the best synergistic effect.2′-FL-DNG6 significantly increased the abundance and diversity of gut microbiota,and boosted beneficial bacteria(such as Bifidobacterium,Lactobacillus,and Akkermansia)abundances(p<0.05).Additionally,2′-FL-DNG6 significantly upregulated Claudin-1,Occludin,and ZO-1 proteins and mRNA expressions,and inhibited TLR4/NF-κB in-flammatory pathway-related proteins and mRNA expressions(p<0.05).Moreover,it significantly reduced the release of TNF-α,IL-1β,IL-6,and myeloperoxidase,while significantly increased levels of IL-10 and short-chain fatty acids(SCFAs)(p<0.05).In conclusion,the combination of 2′-FL and DNG6 could ameliorate intestinal barrier damage and reduce inflammatory response through the SCFAs-TLR4/NF-κB cascade response.These may provide new insights into the different effects of specific Bifidobacteria on improving colitis under different ol-igosaccharides and scientific bases to develop the most effective Bifidobacteria-HMOs combinations for more precise and targeted gut health interventions.展开更多
基金Project(2142005)supported by Beijing Natural Science Foundation,ChinaProject(51401005)supported by the National Natural Science Foundation of China+2 种基金Project(KM201410005014)supported by the Beijing Municipal Commission of Education,ChinaProject(2015-RX-L11)supported by the Ri Xin Talents Plan of Beijing University of Technology,ChinaProject(009000514316007)supported by the Advanced Medical Instruments of Beijing University of Technology,China
文摘The hot deformation behaviors of as-solution Mg?xZn?yEr alloys (x/y=6, x=3.0, 4.5 and 6.0; y=0.50, 0.75 and 1.00) wereinvestigated on Gleeble?1500 thermal simulator in a temperature range of 200?450 °C at a strain rate of 0.001?1 s?1. The truestress?strain curves showed the dynamic competition between the working hardening and working softening mainly due to thedynamic recrystallization (DRX) occurring during hot compression. The constitutive equations were constructed which couldaccurately predict the peak stress of the alloys. The addition of Zn and/or Er resulted in higher deformation activation energy forMg?3Zn?0.5Er (alloy A). The processing maps were constructed as function of the temperature and the strain rate, providing theoptimum hot working conditions (i.e., at strain of 0.3, Mg?3Zn?0.5Er (alloy A): 380?430 ?C, <0.1 s?1; Mg?4.5Zn?0.75Er (alloy B):380?450 ?C, 0.01?0.1 s?1; Mg?6Zn?1Er (alloy C): 390?440 ?C, 0.01?0.1 s?1). The as-solution treated Mg?4.5Zn?0.75Er (alloy B)demonstrated more optimum hot working window comparing with Mg?3Zn?0.5Er (alloy A) and Mg?6Zn?1Er (alloy C).
基金Project(2172013)supported by the Natural Science Foundation of Beijing,ChinaProject(2016YFB0301101)supported by the National Key Research and Development Program,ChinaProject(KZ201810005005)supported by Key Science and Technology Program of Beijing Municipal Commission of Education,China
文摘The microstructure and texture evolutions in Mg-Zn-Er alloy during hot compression were investigated by using opticalmicroscope （OM）, field emission scanning electron microscope （EBSD） and transmission electron microscope （TEM）. The resultsindicate that the temperature plays an important role in dynamic recrystallization （DRX） mechanism. The twin dynamicrecrystallization （TDRX） is induced at a strain of 0.6 because of the activation of non-basal slip （a＋c ） dislocations at 200 ℃.Meanwhile, the continuous DRX （CDRX） occurs at 350℃, which is identified by the typical necklace-like structure around theresidual initial grains. The DRX contributes to the modification of texture significantly. The tension twins are responsible for theweak texture at 200 ℃. Meanwhile, the decrease in the basal texture is ascribed to the DRX sites which transfer from twinboundaries to initial grain boundaries as the temperature is increased from 200 to 350 ℃.
基金supported by the National Natural Science Foundation of China(32302043)China Postdoctoral Science Foundation(2024M750385)+2 种基金Natural Science Foundation of Heilongjiang Province(LH2023C112)Key Project of Natural Science Foundation of Heilongjiang Province(ZD2022C007)Foundation of National Center of Technology Innovation for Dairy(2022-KFKT-12).
文摘The synergistic effects of 2′-Fucosyllactose(2′-FL)or galactooligosaccharide(GOS)with Bifidobacterium bifidum DNG6(DNG6)attenuating dextran sulfate sodium(DSS)-induced colitis in mice were investigated.The results showed that DNG6,2′-FL and GOS alone or in combination could effectively prevent and improve symptoms of colitis.Among them,2′-FL and DNG6(2′-FL-DNG6)demonstrated the best synergistic effect.2′-FL-DNG6 significantly increased the abundance and diversity of gut microbiota,and boosted beneficial bacteria(such as Bifidobacterium,Lactobacillus,and Akkermansia)abundances(p<0.05).Additionally,2′-FL-DNG6 significantly upregulated Claudin-1,Occludin,and ZO-1 proteins and mRNA expressions,and inhibited TLR4/NF-κB in-flammatory pathway-related proteins and mRNA expressions(p<0.05).Moreover,it significantly reduced the release of TNF-α,IL-1β,IL-6,and myeloperoxidase,while significantly increased levels of IL-10 and short-chain fatty acids(SCFAs)(p<0.05).In conclusion,the combination of 2′-FL and DNG6 could ameliorate intestinal barrier damage and reduce inflammatory response through the SCFAs-TLR4/NF-κB cascade response.These may provide new insights into the different effects of specific Bifidobacteria on improving colitis under different ol-igosaccharides and scientific bases to develop the most effective Bifidobacteria-HMOs combinations for more precise and targeted gut health interventions.
