Department of Chemical Engineering, Polytechnique Montreal, QC, Canada.
Department of Engineering Physics, Polytechnique Montreal, QC, Canada.
Talanta. 2018 Apr 1;180:403-409. doi: 10.1016/j.talanta.2017.11.026. Epub 2017 Nov 20.
The present paper presents a new approach for k-NAA for accurate quantification with short turnaround analysis times for rare earth elements (REEs) in high content mineral matrices. REE k and Q values, spectral interferences and nuclear interferences were experimentally evaluated and improved with Alfa Aesar Specpure Plasma Standard 1000mgkg mono-rare earth solutions. The new iterative gamma-ray self-attenuation and neutron self-shielding methods were investigated with powder standards prepared from 100mg of 99.9% Alfa Aesar mono rare earth oxide diluted with silica oxide. The overall performance of the new k-NAA method for REEs was validated using a certified reference material (CRM) from Canadian Certified Reference Materials Project (REE-2) with REE content ranging from 7.2mgkg for Yb to 9610mgkg for Ce. The REE concentration was determined with uncertainty below 7% (at 95% confidence level) and proved good consistency with the CRM certified concentrations.
本文提出了一种新的 k-NAA 方法，用于在高含量矿物基质中对稀土元素 (REE) 进行准确定量，并具有较短的周转分析时间。通过实验评估和改进 Alfa Aesar Specpure Plasma Standard 1000mgkg 单一稀土元素溶液，对 REE 的 k 和 Q 值、光谱干扰和核干扰进行了评估和改进。使用由 100mg 99.9% Alfa Aesar 单一稀土氧化物与氧化硅稀释而成的粉末标准，研究了新的迭代伽马射线自衰减和中子自屏蔽方法。使用来自加拿大认证参考物质项目 (REE-2) 的认证参考物质 (CRM) 对新的 k-NAA REE 方法的整体性能进行了验证，该 CRM 的 REE 含量范围从 7.2mgkg 的 Yb 到 9610mgkg 的 Ce。REE 浓度的测定不确定度低于 7%（置信水平为 95%），并与 CRM 认证浓度具有良好的一致性。
