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~(63)Cu的丰度值和热中子活化截面较大(69.09%,4.5巴),在理想条件下铜的分析灵敏度可达10~(12)—10~(11)克。直到高分辨率的多道γ谱仪问世以前,铜的热中子活化分析大都采用化学分离法,如采用沉淀、电解、离子交换和溶剂萃取等分离方法,制备出放射化学纯的铜化合物,用定标器或NaI探测器进行测量。即使是采用离子交换或溶剂萃取法,为了计算回收率和测量方便,最后一般以硫氰化亚铜的形式予以沉淀。化学分离法具有不受基体和其他杂质核素的干扰、准确度高等优点,但分离步骤多、操作繁杂、周期长。近年来,由于带高分辨率探测器的多道谱仪比较普及,采用不破坏法测定铜者较多。该法固然简单,但往往存在不少问题,例如,一般以β~+湮没产生的511keVγ光子光电峰来定量铜,而~(24)Na、~(65)Zn、~(85)Sr等核素均能生成511keV的光电峰,都会干扰~(64)Cu的测定,其中干扰最甚者为~(24)Na和~(65)Zn。~(24)Na的干扰有人采用扣除的方法进行校正,而扣除的比例各有差异,
The abundance value of 63 Cu and the thermal neutron activation cross section are larger (69.09%, 4.5 bar). Under the ideal conditions, the analytical sensitivity of copper can reach 10 ~ (12) -10 ~ (11) g. Until the advent of high-resolution multi-channel gamma spectrometers, most of the thermal neutron activation analysis of copper used chemical separation methods, such as precipitation, electrolysis, ion exchange and solvent extraction and other separation methods to prepare radiochemically pure copper compounds, Measure with a scaler or NaI detector. Even if ion exchange or solvent extraction is used, precipitation and finally copper (II) sulfide are usually precipitated in order to calculate the recovery rate and measurement convenience. Chemical separation is free from the interference of the substrate and other impurities nuclides, the accuracy of the advantages, but the separation steps, complicated operation, long cycle. In recent years, due to the popularity of multi-channel spectrometers with high-resolution detectors, copper is measured by the non-destructive method. Although this method is simple, it often has many problems. For example, copper is generally quantified by the 511 keVγ photoelectron peak generated by β ~ + annihilation, while nuclei such as ~ (24) Na, ~ (65) Zn and ~ (85) Sr All can generate 511keV photoelectric peak, which will interfere with the determination of ~ (64) Cu, among which the most disturbing ones are ~ (24) Na and ~ (65) Zn. ~ (24) Na interference Some people use the method of deduction to be corrected, and the deduction of the proportion of each difference,