冠醚在Rb和Re中子活化分析中的应用研究

研究了用１８－冠－６（１８Ｃ６）和苯并１５－冠（Ｂ１５Ｃ５）的硝基苯溶液分别从给定ｐＨ范围的苦味酸水溶液或ＫＯＨ溶液中定量萃取Ｒｂ和Ｒｅ，同时研究了影响定量萃取的各种因素以及定量反萃的实验条件，用斜率确定冠醚与金属离子在溶液中生成２：１配合物，冠醚的选择性定量溶液萃取已较好地诮于中子活化分析岩石中微量Ｒｂ和Ｒｅ。     

二环己基18冠6从硝酸溶液和模拟高放废液中萃取镅、钚、铀的研究

研究了二环己基１８ 冠６（ＤＣＨ１８Ｃ６）－正辛醇从硝酸溶液和模拟高放废液中镅、钚、铀的萃取。考察了酸度和模拟高放废液（ＨＬＬＷ）的稀释倍数对萃取分配比的影响。研究结果表明,在低硝酸浓度和较大稀释倍数情况下,ＤＣＨ１８Ｃ６ 对镅、钚、铀的萃取分配比都比较小,并随着水相硝酸浓度的增大而增大,随着模拟高放废液稀释倍数的增大而减小;提高萃取剂浓度会增大四价钚的萃取。     

二环乙基18冠6从硝酸溶液和模拟高放废液中萃取镅,钚,铀？…

研究了二环乙基１８冠６（ＤＣＨ１８Ｃ６）－正辛醇从硝酸溶液和模拟高放废液中镅、钚、铀的萃取。考察了酸度和模拟高放废液（ＨＬＬＷ）的稀释倍数对萃取分配比的影响。研究结果表明,在低硝酸浓度和较大稀释倍数情况下,ＤＣＨ１８Ｃ６对 、钚、铀的萃取分配比都比较小,并随着水相硝酸浓度的增大而增大,随着模拟高放废液稀释倍数的增大而减小;提高萃取剂浓度会增大四价钚的萃取。     

用冠醚从模拟高放废液中去除锶的串级实验

用锶的天然稳定核素代替＾９０Ｓｒ，用二环己基－１８－冠－６（ＤＣＨ１８Ｃ６）－正辛醇溶液作萃取剂对经过ＴＲＰＯ流程去除锕系元素之后的模拟高放废液进行串级实验，结果表明，采用１０级萃取，２级洗涤，４级反萃，锶的去除率可大于９８．７％，并给出了Ｓｒ，Ｋ，Ｍｏ及硝酸等在各级中的浓度剖面及各物流中的相对分布。     

二环己基—18—冠—6在硝酸和模拟高放废液中溶解度的测定

用溶剂萃取法测定了二环己基－１８－冠－６（ＤＣＨ１８Ｃ６）在硝酸和模拟高放废液（ＨＬＬＷ）中的溶解度。实验结果表明，ＤＣＨ１８Ｃ６在水溶液中的溶解度不仅与溶液的酸度、含盐量有关，而且还与冠醚的形态有关。     

冠醚萃取法从高放废液中去除锶─—工艺流程的研究

报道了用二环己基１８冠６（ＤＣ１８Ｃ６）－正辛醇萃取法从模拟高放废液中去除锶的研究。从高放废液中去除半衰期较长的９０Ｓｒ，对于高放废液安全处置有着重要意义。系统地研究了ＤＣ１８Ｃ６－正辛醇对Ｓｒ２＋以及废液中其它阳离子Ｎａ＋、Ｋ＋、Ｃｓ＋、Ｎｉ２＋、Ｆｅ３＋、Ａｌ３＋、Ｍｏ（Ⅵ）的萃取性能。结果表明，ＤＣ１８Ｃ６对Ｓｒ２＋有着良好的萃取选择性，除Ｋ＋和Ｍｏ（Ⅵ）等个别离子外，其它阳离子几乎都不被萃取。在此基础上，建立了用ＤＣ１８Ｃ６－正辛醇从高放浓缩废液中去除锶的工艺流程，并进行了模拟料液的串级实验。经过三级萃取，一级洗涤，四级反萃后，锶的去除率接近９９％，产品中锶的重量百分比为７６％（原始料液中为０．６％）。该流程具有简单、高去除率、高选择性、适用料液酸度范围较宽等优点，可望用于从我国高放浓缩废液中去除或回收锶。     

冠醚萃取法从高放废液中去除锶─—冠醚萃取锶的化学研究

研究了二环己基１８冠６（ＤＣ１８Ｃ６）从硝酸介质中对锶的萃取，选用了正辛醇和第二辛醇作为稀释剂，研究了ＤＣ１８Ｃ６－正辛醇（和第二辛醇）两种萃取体系对锶和硝酸的萃取，同时考察了水相中主要阳离子Ｆｅ３＋、Ａｌ３＋、Ｎａ＋对锶萃取的影响。结果表明，Ｆｅ３＋和Ａｌ３＋对锶的萃取都起着盐析作用，Ｎａ＋在低酸时起盐析作用，而在高酸时起竞争作用。用高放模拟料液进行的实验表明：这两种体系对锶具有较高的萃取能力，并且对其它阳离子有很高的分离系数。反萃实验表明可以用纯水或稀酸从有机相中反萃钢，二次反萃的总反萃率达到９８％以上。根据提出的流程，冠醚萃取法有可能用于从中等酸度（０．５－１．０ｍｏｌ／Ｌ）的高放废液中去除锶。     

冠醚萃取模拟高放废液中Sr^2＋,Cs^＋的研究

用同位素踪法研究冠醚对模拟高放废液中Ｓｒ＾２＋，Ｃｓ＾＋的提取，０．０１ｍｏｌ／ｌ二环己基－１８－冠－６在ＣＨＣｌ２ＣＨＣｌ２和ＣＨＣｌ３中对Ｓｒ＾２＋的一次萃取率在９０％以上，二苯并－２１－冠－７－磷钼酸－硝基苯体系对Ｃｓ＾＋的萃取效果较好。     

冠醚萃取法从高放废液中去除锶Ⅲ．二环己基18冠6－辛醇－［2］对锶的萃取

研究了在硝酸介质中二环已基１８冠６－辛醇－［２］对锶的萃取。结果表明，这种萃取体系对锶具有良好的萃取性能。同时还研究了水相硝酸浓度、平衡时间及锶浓度对萃取的影响。该萃取体系具有较快的反应动力学，锶浓度对萃取没有很大的影响。体系具有良好的反萃性能，可用去离子水作为反萃剂。从模拟高放废液中对锶和其它主要阳离子的萃取分离表明，该体系不仅对锶具有很好的萃取性能，而且对其它阳离子也具有很好的分离性能。     

萃取分离—化学光谱法测定UF4中18种微量杂质元素

应用化学光谱法分析测定了ＵＦ４中的１８种微量杂质元素Ｌｉ、Ｎａ、Ａｌ、Ｍｇ、Ｋ、Ｃａ、Ｍｎ、Ｆｅ、Ｃｕ、Ｃｒ、Ｚｒ、Ｔｉ、Ｍｏ、Ｖ、Ｐ、Ｎｉ、Ｂａ、Ｗ。测定的１８种杂质的质量分数范围为３．２８×１０－１０－１．３１×１０－６；精密度＜２０％；回收率９６．１％－１１１％。     

冠醚溶剂萃取碱金属

用大环多醚溶剂萃取碱金属和碱土金属阳离子已有不少报道。大环多醚与碱金属的阳离子能形成稳定的络合物。在这类络合物中,金属阳离子处于多醚环孔穴的中心,依靠离子-偶极静电作用相互结合。被络合的阳离子的直径和多醚环孔径的吻合程度是影响络合物稳定性的主要因素。通过多醚对碱金属和碱土金属萃取行为的研究,得出萃取平衡常数与金     

Method and portable facility for measurement of trace element concentration in prostate fluid samples using radionuclide-induced energy-dispersive X-ray fluorescent analysis

A facility and method for109 Cd radionuclide-induced energy-dispersive X-ray fluorescent(EDXRF) were developed to determine the Fe,Zn,Br,Rb,and Sr concentrations in the specimens of human prostatic fluid.Specimens of expressed prostatic fluid were obtained from 51 men(mean age 51 years,range 18–82 years) with apparently normal prostates using standard rectal massage procedure.Mean values(M ± SEL) for concentration of trace elements(mg L~(-1)) in human prostate fluid were:Fe 9.04 ±1.21,Zn 573 ± 35,Br 3.58 ± 0.59,Rb 1.10 ± 0.08,and Sr B 0.76.It was shown that the results of trace element analysis in the micro-samples(20 l L) are sufficiently representative for assessment of the Fe,Zn,Br,and Rb concentration in the prostate fluid.The facility for109 Cd radionuclide-induced EDXRF is comparatively compact and can be located in close proximity to the site of carrying out the massage procedure.The means of Zn and Rb concentration obtained for prostate fluid agree well with median of reported means.For the first time,the Fe and Br concentrations,as well as the upper limit of the Sr concentration,were determined in the human prostate fluid.     

Three—body collisions involving Na（3P）,Rb（5S） and buffer gas atoms

Energy pooling in the Na-Rb vapor mixture has been investigated.While some kind of buffer gas is introduced into the cell the peculiar features appear.The buffer gas enhances the energy transfer betwwen Na(3P) and Rb(5S),which can be detected through the effects induced on the highly excited states populated by the Na(3P)/Rb(5P) and Rb(5P)/Rb(5P) collisions.     

t—BAMBP萃取色谱法分离铷,铯的研究

对ｔ Ｂ Ａ Ｍ Ｂ Ｐ萃取色谱法分离铷、铯进行了研究。采用萃取色谱柱实现了铷、铯的完全分离。建立了简便、高效的铷、铯放化分离流程,对铯的去污系数大于 １０６,铷的回收率大于 ８０％ 。     

裂变产物中90Rb的快速放化分离方法研究

为精确测量⁹⁰Rb的衰变数据,需制备出放化纯的⁹⁰Rb样品。本文利用“两步延迟分离法”,建立了一套从新生成的裂变产物中快速分离高丰度⁹⁰Rb的放化流程。该流程先采用抽气法从辐照靶内提取出气体裂变产物⁹⁰Kr,再利用水洗法提取出⁹⁰Kr衰变生成的子体⁹⁰Rb。研制了一套⁹⁰Kr快速提取装置,最终得到了无载体、高比活度的⁹⁰Rb样品。整个分离流程收率约为20%,对主要杂质核素的去污因子达到了10³,操作时间在2.5 min内。     

PIXE measurement of the movement of elements in urine of Rb-treated rats

The movement of K, Ca, Fe, Br and Rb in the urine of Rb-treated rats is investigated by means of PIXE (particle induced X-ray emission) measurements. The excreted amount of Rb per day in urine becomes maximum 1 or 2 days after intraperitoneal injection and then exponentially decreases with a biological half time of 6.60 ± 1.58 days. The integrated amount of excreted Rb in urine over 14 days was 40–50% of the injected one, which is nearly one order of magnitude larger than the previous result obtained by the measurement on Rb-ingested rats. No outstanding time dependencies of the excretion amount per day are found for other elements. Relations between the excretion amounts per day for Rb and those for other elements are less evident.     

Brain trace elements and aging

Degenerative mechanisms involved in the aging process of the brain are to a certain extent counteracted by repair mechanisms. In both degenerative and recovery processes, trace elements are involved. The present study focused on the role of two minor (i.e., K and Ca) and six trace elements (i.e., Mn, Fe, Cu, Zn, Se and Rb) in the aging process. The elements were determined by PIXE in cerebral cortex and white matter, basal ganglia, brainstem and cerebellar cortex of 18 postmortem human brains, from persons without a history of neurologic or psychiatric disease who deceased between the age of 7 and 79. This age range allowed us to study the relationship between elemental concentrations and age. The most prominent findings were a concentration decrease for K and Rb and a concentration increase for the elements Ca, Fe, Zn and Se. The study supports recent findings that Ca and Fe are involved in brain degenerative processes initiated by oxygen free radicals, whereas Zn and Se are involved in immunological reactions counteracting the aging process.     

Study on Preparation Radiochemical of Pure ^91Sr

For measuring the decay data of ^91Sr, it is necessary that the radiochemical pure ^91Sr is firstly prepared. Based on the analysis of the correlative decay chains shows in Fig.l, twice delay separation method is adopted to prepare radiochemical pure ^91Sr. In this method ^235U target is irradiated for short time, and delayed for about l rain to allow ^92Rb and ^93Rb completely decay to ^92Sr and ^93Sr, then Rb is quickly separated; Delaying for about 10 min to allow the ^91Rb decaies to ^91Sr, and then ^91Sr is separated and purified from other impurities.