实验室比对盲样测定是检验实验室能力验证、实验室资质认定、机构考核的主要手段。土壤金属元素污染情况是第三次全国土壤普查的一个重要理化指标,为研究并解决测试实验室比对土壤盲样中铍、钒、镍、铜、锌、镉、铅的含量,采用微波消解...实验室比对盲样测定是检验实验室能力验证、实验室资质认定、机构考核的主要手段。土壤金属元素污染情况是第三次全国土壤普查的一个重要理化指标,为研究并解决测试实验室比对土壤盲样中铍、钒、镍、铜、锌、镉、铅的含量,采用微波消解-电感耦合等离子体质谱(ICP-MS)法对土壤盲样进行研究,对不同消解酸体系、检出限和定量限、测试模式和干扰消除、精密度和加标回收率、质控样品进行了探讨,并与电感耦合等离子体发射光谱(ICP-OES)法进行测试结果比对。结果表明:用6 mL HNO_(3)、2 mL HCl和1 mL HF为混合酸体系,各待测元素标准曲线相关系数大于0.999 5、检出限在0.001~3.0μg/L、定量限在0.003~9.9μg/L,采用氦气碰撞模式测试钒、镍、铜、锌、镉和铅,可以有效地降低多原子离子的干扰;采用no gas模式测试铍,可以有效地提高铍的测试灵敏度。方法精密度为0.2%~6.2%(n=6),加标回收率为92.3%~111%,采用土壤标准样品(GSS-4)进行全过程消解测试质控研究分析,各元素结果均在标准值参考范围内。用ICP-OES法测试土壤盲样中7种待测金属元素含量与用铑为内标的ICP-MS法测定值进行比对,ICP-MS法和ICP-OES法测试的各元素的相对标准偏差分别为0.60%~2.2%和0.70%~3.2%,测量结果基本一致。展开更多
The effects of Ni content（0–2.1wt%）on the cast and solid-solution microstructures of Cu-0.4wt%Be alloys were investigated,and the corresponding mechanisms of influence were analyzed.The results show that the amount...The effects of Ni content（0–2.1wt%）on the cast and solid-solution microstructures of Cu-0.4wt%Be alloys were investigated,and the corresponding mechanisms of influence were analyzed.The results show that the amount of precipitated phase increases in the cast alloys with increasing Ni content.When the Ni content is 0.45wt%or 0.98wt%,needle-like Be_（21）Ni_5 phases form in the grains and are mainly distributed in the interdendritic regions.When the Ni content is 1.5wt%or greater,a large number of needle-like precipitates form in the grains and chain-like Be_（21）Ni_5 and Be Ni precipitates form along the grain boundaries.The addition of Ni can substantially refine the cast and solid-solution microstructures of Cu-0.4wt%Be alloys.The hindering effects of both the dissolution of Ni into the matrix and the formation of Be–Ni precipitates on grain-boundary migration are mainly responsible for refining the cast and solid-solution microstructures of Cu-0.4wt%Be alloys.Higher Ni contents result in finer microstructures;however,given the precipitation characteristics of Be–Ni phases and their dissolution into the matrix during the solid-solution treatment,the upper limit of the Ni content is 1.5wt%–2.1wt%.展开更多
文摘实验室比对盲样测定是检验实验室能力验证、实验室资质认定、机构考核的主要手段。土壤金属元素污染情况是第三次全国土壤普查的一个重要理化指标,为研究并解决测试实验室比对土壤盲样中铍、钒、镍、铜、锌、镉、铅的含量,采用微波消解-电感耦合等离子体质谱(ICP-MS)法对土壤盲样进行研究,对不同消解酸体系、检出限和定量限、测试模式和干扰消除、精密度和加标回收率、质控样品进行了探讨,并与电感耦合等离子体发射光谱(ICP-OES)法进行测试结果比对。结果表明:用6 mL HNO_(3)、2 mL HCl和1 mL HF为混合酸体系,各待测元素标准曲线相关系数大于0.999 5、检出限在0.001~3.0μg/L、定量限在0.003~9.9μg/L,采用氦气碰撞模式测试钒、镍、铜、锌、镉和铅,可以有效地降低多原子离子的干扰;采用no gas模式测试铍,可以有效地提高铍的测试灵敏度。方法精密度为0.2%~6.2%(n=6),加标回收率为92.3%~111%,采用土壤标准样品(GSS-4)进行全过程消解测试质控研究分析,各元素结果均在标准值参考范围内。用ICP-OES法测试土壤盲样中7种待测金属元素含量与用铑为内标的ICP-MS法测定值进行比对,ICP-MS法和ICP-OES法测试的各元素的相对标准偏差分别为0.60%~2.2%和0.70%~3.2%,测量结果基本一致。
基金financially supported by the National Key Research and Development Program of China (No.2016YFB0301300)
文摘The effects of Ni content（0–2.1wt%）on the cast and solid-solution microstructures of Cu-0.4wt%Be alloys were investigated,and the corresponding mechanisms of influence were analyzed.The results show that the amount of precipitated phase increases in the cast alloys with increasing Ni content.When the Ni content is 0.45wt%or 0.98wt%,needle-like Be_（21）Ni_5 phases form in the grains and are mainly distributed in the interdendritic regions.When the Ni content is 1.5wt%or greater,a large number of needle-like precipitates form in the grains and chain-like Be_（21）Ni_5 and Be Ni precipitates form along the grain boundaries.The addition of Ni can substantially refine the cast and solid-solution microstructures of Cu-0.4wt%Be alloys.The hindering effects of both the dissolution of Ni into the matrix and the formation of Be–Ni precipitates on grain-boundary migration are mainly responsible for refining the cast and solid-solution microstructures of Cu-0.4wt%Be alloys.Higher Ni contents result in finer microstructures;however,given the precipitation characteristics of Be–Ni phases and their dissolution into the matrix during the solid-solution treatment,the upper limit of the Ni content is 1.5wt%–2.1wt%.
