Achieving high strength in Mg alloys is usually accompanied by ductility loss.Here,a novel Mg97Y1Zn1Ho1 at.%alloy with a yield strength of 403 MPa and an elongation of 10%is developed.The strength-ductility synergy is...Achieving high strength in Mg alloys is usually accompanied by ductility loss.Here,a novel Mg97Y1Zn1Ho1 at.%alloy with a yield strength of 403 MPa and an elongation of 10%is developed.The strength-ductility synergy is obtained by a comprehensive strategy,including a lamella bimodal microstructure design and the introduction of nano-spaced solute-segregated 14H long-period stacking-ordered phase(14H LPSO phase)through rare-earth Ho alloying.The lamella bimodal microstructure consists of elongated un-recrystallized(un-DRXed)coarse grains and fine dynamically-recrystallized grains(DRXed regions).The nano-spaced solute-segregated 14H LPSO phase is distributed in DRXed regions.The outstanding yield strength is mainly contributed by grain-boundary strengthening,18R LPSO strengthening,and fiberlike reinforcement strengthening from the nano-spaced 14H LPSO phase.The high elongation is due primarily to the combined effects of the bimodal and lamellar microstructures through enhancing the work-hardening capability.展开更多
The electron injection and acceleration driven by a few-cycle laser with a sharp vacuum-plasma boundary have been investigated through three-dimensional(3D)particle-in-cell simulations.It is found that an isotropic bo...The electron injection and acceleration driven by a few-cycle laser with a sharp vacuum-plasma boundary have been investigated through three-dimensional(3D)particle-in-cell simulations.It is found that an isotropic boundary impact injection(BII)first occurs at the vacuum-plasma boundary,and then carrier-envelope-phase(CEP)shift causes the transverse oscillation of the plasma bubble,resulting in a periodic electron self-injection(SI)in the laser polarization direction.It shows that the electron charge of the BII only accounts for a small part of the total charge,and the CEP can effectively tune the quality of the injected electron beam.The dependences of laser intensity and electron density on the total charge and the ratio of BII charge to the total charge are studied.The results are beneficial to electron acceleration and its applications,such as betatron radiation source.展开更多
Drought stress limits the growth and development of grapevines,thereby reducing productivity,but the mechanisms by which grapevines respond to drought stress remain largely uncharacterized.Here,we characterized a grou...Drought stress limits the growth and development of grapevines,thereby reducing productivity,but the mechanisms by which grapevines respond to drought stress remain largely uncharacterized.Here,we characterized a group A bZIP gene from“Kyoho”grapevine,VlbZIP30,which was shown to be induced by abscisic acid(ABA)and dehydration stress.Overexpression of VlbZIP30 in transgenic Arabidopsis thaliana enhanced dehydration tolerance.Transcriptome analysis revealed that a major proportion of ABA-responsive and/or drought-responsive genes are transcriptionally regulated by VlbZIP30 during ABA or mannitol treatment at the cotyledon greening stage.We identified an A.thaliana G-box motif(CACGTG)and a potential grapevine G-box motif(MCACGTGK)in the promoters of the 39 selected A.thaliana genes upregulated in the transgenic plants and in the 35 grapevine homologs,respectively.Subsequently,using two grapevine-related databases,we found that 74%(23/31)and 84%(21/25)of the detected grapevine genes were significantly upregulated by ABA and drought stress,respectively,suggesting that these genes are involved in ABA or dehydration stress and may be regulated by VlbZIP30 in grapevine.We propose that VlbZIP30 functions as a positive regulator of dehydration-responsive signaling in the ABA core signaling pathway.展开更多
基金supported by the National Key Research and Development Project (2018YFE0115800, 2020YFE0202600)Youth Talent Project of China National Nuclear Corporation (CNNC2019YTEP-HEU01, CNNC2021YTEP-HEU01)+4 种基金the NSFC Funding (51701051, 52001083, 52171111, U2141207)China Postdoctoral Science Foundation Funded Project (2019T120255)Natural Science Foundation of Heilongjiang (LH2019E030)Heilongjiang Touyan Innovation Team Programthe supports from the U.S. National Science Foundation [DMR-1611180 and 1809640] with the program directors, Drs. Judith Yang, Gary Shiflet, and Diana Farkas.
文摘Achieving high strength in Mg alloys is usually accompanied by ductility loss.Here,a novel Mg97Y1Zn1Ho1 at.%alloy with a yield strength of 403 MPa and an elongation of 10%is developed.The strength-ductility synergy is obtained by a comprehensive strategy,including a lamella bimodal microstructure design and the introduction of nano-spaced solute-segregated 14H long-period stacking-ordered phase(14H LPSO phase)through rare-earth Ho alloying.The lamella bimodal microstructure consists of elongated un-recrystallized(un-DRXed)coarse grains and fine dynamically-recrystallized grains(DRXed regions).The nano-spaced solute-segregated 14H LPSO phase is distributed in DRXed regions.The outstanding yield strength is mainly contributed by grain-boundary strengthening,18R LPSO strengthening,and fiberlike reinforcement strengthening from the nano-spaced 14H LPSO phase.The high elongation is due primarily to the combined effects of the bimodal and lamellar microstructures through enhancing the work-hardening capability.
基金the National Natural Science Foundation of China(Grant Nos.12005297,12175309,12175310,11975308,and 12275356)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA25050200)+3 种基金the Research Project of NUDT(Grant No.ZK21-12)the Key Laboratory Foundation of Laser Plasma of Ministry of Educationthe financial support from the NUDT Young Innovator Awards(Grant No.20190102)Outstanding Young Talents。
文摘The electron injection and acceleration driven by a few-cycle laser with a sharp vacuum-plasma boundary have been investigated through three-dimensional(3D)particle-in-cell simulations.It is found that an isotropic boundary impact injection(BII)first occurs at the vacuum-plasma boundary,and then carrier-envelope-phase(CEP)shift causes the transverse oscillation of the plasma bubble,resulting in a periodic electron self-injection(SI)in the laser polarization direction.It shows that the electron charge of the BII only accounts for a small part of the total charge,and the CEP can effectively tune the quality of the injected electron beam.The dependences of laser intensity and electron density on the total charge and the ratio of BII charge to the total charge are studied.The results are beneficial to electron acceleration and its applications,such as betatron radiation source.
基金This work was supported by the National Natural Science Foundation of China(31572110)as well as the Program for Innovative Research Team of Grape Germplasm Resources and Breeding(2013KCT-25).
文摘Drought stress limits the growth and development of grapevines,thereby reducing productivity,but the mechanisms by which grapevines respond to drought stress remain largely uncharacterized.Here,we characterized a group A bZIP gene from“Kyoho”grapevine,VlbZIP30,which was shown to be induced by abscisic acid(ABA)and dehydration stress.Overexpression of VlbZIP30 in transgenic Arabidopsis thaliana enhanced dehydration tolerance.Transcriptome analysis revealed that a major proportion of ABA-responsive and/or drought-responsive genes are transcriptionally regulated by VlbZIP30 during ABA or mannitol treatment at the cotyledon greening stage.We identified an A.thaliana G-box motif(CACGTG)and a potential grapevine G-box motif(MCACGTGK)in the promoters of the 39 selected A.thaliana genes upregulated in the transgenic plants and in the 35 grapevine homologs,respectively.Subsequently,using two grapevine-related databases,we found that 74%(23/31)and 84%(21/25)of the detected grapevine genes were significantly upregulated by ABA and drought stress,respectively,suggesting that these genes are involved in ABA or dehydration stress and may be regulated by VlbZIP30 in grapevine.We propose that VlbZIP30 functions as a positive regulator of dehydration-responsive signaling in the ABA core signaling pathway.
