This study reported the synthesis of magnetic solid solutions V2(A_(x)B_(y)Sn_(1-x-y))C(where A and B are Mn,Fe,or Co)MAX phases.These materials were prepared by incorporating magnetic elements into the V_(2)SnC MAX p...This study reported the synthesis of magnetic solid solutions V2(A_(x)B_(y)Sn_(1-x-y))C(where A and B are Mn,Fe,or Co)MAX phases.These materials were prepared by incorporating magnetic elements into the V_(2)SnC MAX phase via pressure-less sintering at 1000℃for 3 hours.XRD analysis reveals that the composition with x=y=0.2 exhibits a shift of diffraction peaks to higher angles,indicating lattice parameter changes,and achieves the highest phase purity with the maximum solid solution limit,further increases in the dopant content led to the formation of impurities.While the solid solution of magnetic elements preserves the characteristic layered structure of the MAX phase,it successfully induces magnetic properties.The magnetic transition temperatures for these solid solutions ranges from 61 to 200 K.Specifically,V_(2)(Mn_(x)Co_(y)Sn_(1-x-y))C demonstrated hard magnetic characteristics,with a high saturation magnetization(6.536 emu/g)and large remanence(4.236 emu/g).In contrast,V_(2)(Mn_(x)Fe_(y)Sn_(1-x-y))C and V2(Fe_(x)Co_(y)Sn_(1-x-y))C exhibits soft magnetic behavior,evidenced by their narrow hysteresis loops and low coercivity.Their saturation magnetization values are 3.80 and 1.784 emu/g,respectively.The distinctly"S"-shaped hysteresis loop of V_(2)(Fe_(x)Co_(y)Sn_(1-x-y))C further confirms its soft magnetic nature.展开更多
以陆地棉中35和军棉1号的茎尖为外植体,利用农杆菌介导法将含有拟南芥抗病基因SNC1(sup-pressor of npr1-1,constitutive 1)转入棉花。对外植体培养时期、农杆菌侵染时间和共培养时间进行改良,实验结果表明,在外植体培养1d,菌液侵染20m...以陆地棉中35和军棉1号的茎尖为外植体,利用农杆菌介导法将含有拟南芥抗病基因SNC1(sup-pressor of npr1-1,constitutive 1)转入棉花。对外植体培养时期、农杆菌侵染时间和共培养时间进行改良,实验结果表明,在外植体培养1d,菌液侵染20min,并且共培养保持在2d能够获得较高的遗传转化效率。PCR以及RT-PCR对再生植株T0代和T1代棉花的检测结果表明,SNC1基因已经整合到棉花的基因组中并得到表达。利用浸根法,对T1代转基因棉花接种棉花枯萎病菌强致病力菌株(Fusarium oxysporum f.sp.Vasinfectum),与对照比较,T1代转基因棉花的枯萎病抗性明显提高。展开更多
【目的】棉花抵御外来病原物侵害的途径是多种多样的,研究抗病转基因棉和非转基因棉在组织结构上的抗性差异。【方法】利用茎尖遗传转化获得的转SNC1(suppressor of npr1-1,constitutive)基因棉花"中35"和"军棉1号"...【目的】棉花抵御外来病原物侵害的途径是多种多样的,研究抗病转基因棉和非转基因棉在组织结构上的抗性差异。【方法】利用茎尖遗传转化获得的转SNC1(suppressor of npr1-1,constitutive)基因棉花"中35"和"军棉1号",通过营养钵伤根法对其接种棉花枯萎病菌菌株,借助石蜡切片技术,观察棉株根茎部细胞解剖结构。【结果】抗病转基因棉根茎部胼胝质、侵填体和胶质体形成多于非转基因棉,并且韧皮部细胞排列紧密,规整,细胞间隙小。【结论】组织结构抗性在棉花抵御外来病原物侵害时所起到的至关重要的作用。展开更多
基金Funded by the National Natural Science Foundation for Young Scholars of China(No.51302073)the Hubei Provincial Key Laboratory of Green Materials for Light Industry,Hubei University of Technology(No.202509B13)。
文摘This study reported the synthesis of magnetic solid solutions V2(A_(x)B_(y)Sn_(1-x-y))C(where A and B are Mn,Fe,or Co)MAX phases.These materials were prepared by incorporating magnetic elements into the V_(2)SnC MAX phase via pressure-less sintering at 1000℃for 3 hours.XRD analysis reveals that the composition with x=y=0.2 exhibits a shift of diffraction peaks to higher angles,indicating lattice parameter changes,and achieves the highest phase purity with the maximum solid solution limit,further increases in the dopant content led to the formation of impurities.While the solid solution of magnetic elements preserves the characteristic layered structure of the MAX phase,it successfully induces magnetic properties.The magnetic transition temperatures for these solid solutions ranges from 61 to 200 K.Specifically,V_(2)(Mn_(x)Co_(y)Sn_(1-x-y))C demonstrated hard magnetic characteristics,with a high saturation magnetization(6.536 emu/g)and large remanence(4.236 emu/g).In contrast,V_(2)(Mn_(x)Fe_(y)Sn_(1-x-y))C and V2(Fe_(x)Co_(y)Sn_(1-x-y))C exhibits soft magnetic behavior,evidenced by their narrow hysteresis loops and low coercivity.Their saturation magnetization values are 3.80 and 1.784 emu/g,respectively.The distinctly"S"-shaped hysteresis loop of V_(2)(Fe_(x)Co_(y)Sn_(1-x-y))C further confirms its soft magnetic nature.
文摘【目的】棉花抵御外来病原物侵害的途径是多种多样的,研究抗病转基因棉和非转基因棉在组织结构上的抗性差异。【方法】利用茎尖遗传转化获得的转SNC1(suppressor of npr1-1,constitutive)基因棉花"中35"和"军棉1号",通过营养钵伤根法对其接种棉花枯萎病菌菌株,借助石蜡切片技术,观察棉株根茎部细胞解剖结构。【结果】抗病转基因棉根茎部胼胝质、侵填体和胶质体形成多于非转基因棉,并且韧皮部细胞排列紧密,规整,细胞间隙小。【结论】组织结构抗性在棉花抵御外来病原物侵害时所起到的至关重要的作用。
