The high cost of using the niobium(Nb)barrier for manufacturing magnesium diboride(MgB2)mono-and multi-filamentary wires for large-scale applications has become one of the barriers to replacing current commercial niob...The high cost of using the niobium(Nb)barrier for manufacturing magnesium diboride(MgB2)mono-and multi-filamentary wires for large-scale applications has become one of the barriers to replacing current commercial niobium-titanium superconductors.The potential of replacing the Nb barrier with a low-cost iron(Fe)barrier for multifilament MgB2 superconducting wires is investigated in this manuscript.Therefore,MgB2 wires with Fe barrier sintered with different temperatures are studied(from 650°C to 900°C for 1 h)to investigate the non-superconducting reaction phase of Fe-B.Their superconducting performance including engineering critical current density(Je)and n-value are tested at 4.2 K in various external magnetic fields.The best sample sintered at 650°C for 1 h has achieved a Je value of 3.64×10^(4) A cm^(−2) and an n-value of 61 in 2 T magnetic field due to the reduced formation of Fe2B,better grain connectivity and homogenous microstructure.For microstructural analysis,the focused ion beam(FIB)is utilised for the first time to acquire three-dimensional microstructures and elemental mappings of the interface between the Fe barrier and MgB2 core of different wires.The results have shown that if the sintering temperature can be controlled properly,the Je and n-value of the wire are still acceptable for magnet applications.The formation of Fe2B is identified along the edge of MgB2,as the temperature increases,the content of Fe2B also increases which causes the degradation in the performance of wires.展开更多
目的建立TaqMan-MGB探针检测CYP2C19基因*2、*3和*17三个多态性位点的方法。方法针对CYP2C19基因*2、*3和*17位点设计合成相应引物及双标记探针。选取2021年3月至2022年6月贵州省人民医院心内科门诊已知基因型的剩余全血样本42例,覆盖...目的建立TaqMan-MGB探针检测CYP2C19基因*2、*3和*17三个多态性位点的方法。方法针对CYP2C19基因*2、*3和*17位点设计合成相应引物及双标记探针。选取2021年3月至2022年6月贵州省人民医院心内科门诊已知基因型的剩余全血样本42例,覆盖每个位点的每个基因型各10例,提取DNA进行聚合酶链反应(PCR)检测,产物进行电泳和Sanger法测序分析。加样1、10、100、800 ng DNA,进行PCR检测以评价灵敏度。每个位点的每个基因型5例,每周1次对其检测,连续3周,以评价重复性。结果设计的引物扩增出目的基因片段,电泳显示明亮的单一的DNA条带;90个基因型的PCR结果与测序结果完全一致(P>0.05);不同加样量PCR法均可准确判读基因型,所有基因型在1 ng水平的Ct值均<34。同一基因型3次重复检测的结果一致。结论本研究成功建立了TaqMan-MGB探针检测CYP2C19基因*2、*3和*17三个多态性位点的方法,具有快速、准确、灵敏、简便的特点。展开更多
菜豆荚斑驳病毒(Bean pod mottle virus,BPMV)是我国重要的检疫性有害生物,BPMV传入的风险随大豆进境数量增多而加大。本文针对菜豆荚斑驳病毒,以大豆种子提取液为材料,分别建立了TaqMan-MGB荧光定量IC-RTPCR和TaqMan-MGB荧光定量TC-RT-...菜豆荚斑驳病毒(Bean pod mottle virus,BPMV)是我国重要的检疫性有害生物,BPMV传入的风险随大豆进境数量增多而加大。本文针对菜豆荚斑驳病毒,以大豆种子提取液为材料,分别建立了TaqMan-MGB荧光定量IC-RTPCR和TaqMan-MGB荧光定量TC-RT-PCR快速检测方法。根据GenBank公布的BPMV外壳蛋白基因序列,选择其保守区域,设计1对特异性引物和1条TaqMan-MGB探针,测定了TaqMan-MGB荧光定量IC-RT-PCR和TaqMan-MGB荧光定量TC-RT-PCR方法的特异性和灵敏度,并将TaqMan-MGB荧光定量IC-RT-PCR、TaqMan-MGB荧光定量TC-RTPCR、IC-RT-PCR和TC-RT-PCR 4种检测方法的灵敏度进行比较。结果表明:所建立的两种检测方法特异性良好;TCRT-PCR的灵敏度为10-1倍病毒提取液原液;IC-RT-PCR和TaqMan-MGB荧光定量TC-RT-PCR灵敏度相当,为10-3倍病毒提取液原液;TaqMan-MGB荧光定量IC-RT-PCR灵敏度最高,为10-5倍病毒提取液原液,是IC-RT-PCR和TaqMan-MGB荧光定量TC-RT-PCR检测方法的102倍,是TC-RT-PCR检测方法的104倍;两种检测方法均能较好应用于实际大豆样品的检测。本文所建立的TaqMan-MGB荧光定量IC/TC-RT-PCR检测方法利用抗原特异性或试管非特异性捕捉病毒粒子,无需提取RNA,为进境大豆种子上BPMV的检测提供了稳定、快速、简便的技术依据,其较高的灵敏度和特异性具有较好的应用价值。展开更多
以小麦印度腥黑穗病菌9个菌株和黑麦草腥黑穗病菌5个菌株及其近似种或相关种:稻粒黑粉菌、狼尾草腥黑粉菌、狗尾草腥黑粉菌、苏玛特腥黑粉菌、狐尾草腥黑粉菌、小麦网腥黑穗病菌和小麦矮化腥黑穗病菌共9种22个菌株为研究对象,通过序列...以小麦印度腥黑穗病菌9个菌株和黑麦草腥黑穗病菌5个菌株及其近似种或相关种:稻粒黑粉菌、狼尾草腥黑粉菌、狗尾草腥黑粉菌、苏玛特腥黑粉菌、狐尾草腥黑粉菌、小麦网腥黑穗病菌和小麦矮化腥黑穗病菌共9种22个菌株为研究对象,通过序列比对分析,设计了检测小麦印度腥黑穗病菌及黑麦草腥黑穗病菌的TaqM an MGB实时荧光PCR引物和探针,优化了反应条件,筛选出特异性探针,分别建立了小麦印度腥黑穗病菌和黑麦草腥黑穗病菌实时荧光单重PCR和实时荧光双重PCR检测方法,其中实时荧光双重PCR检测方法实现了在同一PCR管中仅用5μL的反应体系,进行1次PCR反应就能特异性检测出小麦印度腥黑穗病菌或黑麦草腥黑穗病菌。本研究所建立的检测方法特异性强、结果可靠、检测速度快、成本明显降低,在实际应用中具有推广价值。展开更多
基金support from the Australian Research Council(ARC)Linkage Project(LP200200689).
文摘The high cost of using the niobium(Nb)barrier for manufacturing magnesium diboride(MgB2)mono-and multi-filamentary wires for large-scale applications has become one of the barriers to replacing current commercial niobium-titanium superconductors.The potential of replacing the Nb barrier with a low-cost iron(Fe)barrier for multifilament MgB2 superconducting wires is investigated in this manuscript.Therefore,MgB2 wires with Fe barrier sintered with different temperatures are studied(from 650°C to 900°C for 1 h)to investigate the non-superconducting reaction phase of Fe-B.Their superconducting performance including engineering critical current density(Je)and n-value are tested at 4.2 K in various external magnetic fields.The best sample sintered at 650°C for 1 h has achieved a Je value of 3.64×10^(4) A cm^(−2) and an n-value of 61 in 2 T magnetic field due to the reduced formation of Fe2B,better grain connectivity and homogenous microstructure.For microstructural analysis,the focused ion beam(FIB)is utilised for the first time to acquire three-dimensional microstructures and elemental mappings of the interface between the Fe barrier and MgB2 core of different wires.The results have shown that if the sintering temperature can be controlled properly,the Je and n-value of the wire are still acceptable for magnet applications.The formation of Fe2B is identified along the edge of MgB2,as the temperature increases,the content of Fe2B also increases which causes the degradation in the performance of wires.
文摘目的建立TaqMan-MGB探针检测CYP2C19基因*2、*3和*17三个多态性位点的方法。方法针对CYP2C19基因*2、*3和*17位点设计合成相应引物及双标记探针。选取2021年3月至2022年6月贵州省人民医院心内科门诊已知基因型的剩余全血样本42例,覆盖每个位点的每个基因型各10例,提取DNA进行聚合酶链反应(PCR)检测,产物进行电泳和Sanger法测序分析。加样1、10、100、800 ng DNA,进行PCR检测以评价灵敏度。每个位点的每个基因型5例,每周1次对其检测,连续3周,以评价重复性。结果设计的引物扩增出目的基因片段,电泳显示明亮的单一的DNA条带;90个基因型的PCR结果与测序结果完全一致(P>0.05);不同加样量PCR法均可准确判读基因型,所有基因型在1 ng水平的Ct值均<34。同一基因型3次重复检测的结果一致。结论本研究成功建立了TaqMan-MGB探针检测CYP2C19基因*2、*3和*17三个多态性位点的方法,具有快速、准确、灵敏、简便的特点。
文摘菜豆荚斑驳病毒(Bean pod mottle virus,BPMV)是我国重要的检疫性有害生物,BPMV传入的风险随大豆进境数量增多而加大。本文针对菜豆荚斑驳病毒,以大豆种子提取液为材料,分别建立了TaqMan-MGB荧光定量IC-RTPCR和TaqMan-MGB荧光定量TC-RT-PCR快速检测方法。根据GenBank公布的BPMV外壳蛋白基因序列,选择其保守区域,设计1对特异性引物和1条TaqMan-MGB探针,测定了TaqMan-MGB荧光定量IC-RT-PCR和TaqMan-MGB荧光定量TC-RT-PCR方法的特异性和灵敏度,并将TaqMan-MGB荧光定量IC-RT-PCR、TaqMan-MGB荧光定量TC-RTPCR、IC-RT-PCR和TC-RT-PCR 4种检测方法的灵敏度进行比较。结果表明:所建立的两种检测方法特异性良好;TCRT-PCR的灵敏度为10-1倍病毒提取液原液;IC-RT-PCR和TaqMan-MGB荧光定量TC-RT-PCR灵敏度相当,为10-3倍病毒提取液原液;TaqMan-MGB荧光定量IC-RT-PCR灵敏度最高,为10-5倍病毒提取液原液,是IC-RT-PCR和TaqMan-MGB荧光定量TC-RT-PCR检测方法的102倍,是TC-RT-PCR检测方法的104倍;两种检测方法均能较好应用于实际大豆样品的检测。本文所建立的TaqMan-MGB荧光定量IC/TC-RT-PCR检测方法利用抗原特异性或试管非特异性捕捉病毒粒子,无需提取RNA,为进境大豆种子上BPMV的检测提供了稳定、快速、简便的技术依据,其较高的灵敏度和特异性具有较好的应用价值。
文摘以小麦印度腥黑穗病菌9个菌株和黑麦草腥黑穗病菌5个菌株及其近似种或相关种:稻粒黑粉菌、狼尾草腥黑粉菌、狗尾草腥黑粉菌、苏玛特腥黑粉菌、狐尾草腥黑粉菌、小麦网腥黑穗病菌和小麦矮化腥黑穗病菌共9种22个菌株为研究对象,通过序列比对分析,设计了检测小麦印度腥黑穗病菌及黑麦草腥黑穗病菌的TaqM an MGB实时荧光PCR引物和探针,优化了反应条件,筛选出特异性探针,分别建立了小麦印度腥黑穗病菌和黑麦草腥黑穗病菌实时荧光单重PCR和实时荧光双重PCR检测方法,其中实时荧光双重PCR检测方法实现了在同一PCR管中仅用5μL的反应体系,进行1次PCR反应就能特异性检测出小麦印度腥黑穗病菌或黑麦草腥黑穗病菌。本研究所建立的检测方法特异性强、结果可靠、检测速度快、成本明显降低,在实际应用中具有推广价值。
