CL—5209萃淋树脂吸附钍的性能和机理研究   总被引：1，自引：0，他引：1  

宋金如  龚治湘 《华东地质学院学报》2000,23(4):271-276,304

研究了ＣＬ－５２０９萃淋树脂吸附钍的性能和机理,并用减压微色谱柱考察了相关离子的萃取色谱行为。选择了分离钍的最佳条件,用于矿样中微量钍的分离和测定,取得了满意结果。  相似文献   

闪烁法测氡仪α检查源对比实验     

李朝明  杨志坚  褚金学  吴谋 《地震地磁观测与研究》2018,39(2):165-172

检查和选取闪烁法测氡仪的工作高压、阈值电压是保证仪器正常工作的重要环节,α检查源作为确定工作高压和阈值电压的有效工具,可简便、快速地测试测氡仪“高压坪曲线”和“甄别阈值曲线”。使用下关地震台原有和新配的²³⁹Pu标准固体α检查源,对新购置FD-125型室内氡钍分析器进行对比检查实验,结果表明：使用原示值为24 000脉冲/min的固体α检查源进行检查,误差≤ 5%的坪区为210 V,符合相应规范要求,确定工作高压为-663 V、阈值电压为2.0 V;用测值为860脉冲/min的固体α检查源进行检查,误差≤ 5%无坪区,误差≤ 10%的坪区为120 V,误差范围大,坪区不稳定,确定工作高压为-673 V、阈值电压为2.0 V。分析认为：固体α检查源的强度弱,检查结果不稳定,坪区窄、误差大,坪区特点表现不显著,选择²³⁹Pu固体α检查源时需充分考虑其强度对坪区长度的影响。  相似文献   

应用中子活化分析技术测定铀和钍放射性同位素的α能谱内标法   总被引：1，自引：0，他引：1  

《国外铀金地质》1999,16(4):380-382,384

开发了一种用＾２３８Ｕ和＾２３２Ｔｈ作为内标的α能谱测定铀和钍放射性同位新方法。应用中子活化分析技术精确地测定样品中的＾２３８Ｕ和２３２Ｔｈ。将其他部分样品全部溶解,采用阴离子交换法分离铀和钍,制备为α能谱测定的电镀薄（低强度）源。人已知的＾２３８Ｕ和＾２３２Ｔｈ质量浓度,求得它们的活度浓度,之后据α能谱,从Ｕ（＾２３Ｕ、＾２３５Ｕ、＾２３８Ｕ）和Ｔｈ（＾２２８Ｔｈ、＾２３０Ｔｈ、２３２Ｔｈ）放射  相似文献   

Influence of particle composition on thorium scavenging in the marginal China seas     

YANG Weifeng  CHEN Min  CAO Jianping  QIU Yusheng  ZHANG Run  MA Qiang  TONG Jinlu  YANG Junhong  YANG Zhi  L&#; E 《海洋学报(英文版)》2009,28(2):45-53

Thorium-234 and particle composition (organic matter, biogenic silica, carbonate and lithogenic component) were examined in the East China Sea (ECS) and the northern South China Sea (NSCS) in order to constrain the particle types scavenging thorium isotopes. Good positive correlations between particulate organic matter (POM) or carbonate and thorium-234 in suspended particulate matter (SPM) indicates that POM and carbonate are efficient to scavenge thorium-234. No relationship between biogenic silica and thorium-234 suggests that geochemical behavior of thorium-234 may be not influenced by biogenic silica. A simple model was used to evaluate the affinity of thorium-234 to different particle components. The results show that POM is the most efficient scavenger for thorium-234 in the ECS and the NSCS, followed by carbonate. The authors'' results lend support to the utility of thorium-234 as a proxy of POC and carbonate in the upper layer. However, the strong dependence of thorium scavenging on particle composition challenges thorium-230 as a constant flux proxy.  相似文献