用^234Th为产额示踪剂,分光光度法测定环境水中钍的浓度

本文介绍了一种测定环境水中钍浓度的分析方法，１０Ｌ环境水要用氢氧化铁沉淀法浓集钍，阴离子交换树脂除除杂质，分光光度法测定钍浓度，全过程用＾２３４Ｔｈ作为产额示踪剂，进行回收率校正，方法探测下限为１．９×１０＾－５Ｂｑ／Ｌ，回收率均值为（８０．５±４．７）％，用本方法对本省１１个地区的自来水，井水，河水，湖水及温泉水进行了分析，结果表明，各种水样中钍浓度的均值为０．２０～２．６３ｍＢｑ／Ｌ。     

DBN—偶氮胂在微量钍的分光光度测定中的应用

以ＤＢＮ－偶氮胂作为微量钍的的分光光度测定的显色剂。结果表明，在１ｍｏｌ／Ｌ ＨＣｌ溶液中，ＤＢＮ－偶氮胂和钍的络合物在λ＝６３０ｎｍ处的表观摩尔吸光系数为８．６×１０＾４Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，并且可在高达９０倍的铀存在下测定微克级的钍。在０－１３μｇ Ｔｈ／１０ｍｌ范围内符合比耳定律，标准曲线线性良好，相关系数ｒ＝０．９９９１。在３０％ＴＢＰ－煤油溶液中采用互溶法，可用ＤＢＮ－偶氮胂直接     

活性炭吸附剂用于大体积水中铀,钍浓集的方法研究

对ＩＲＰ—２活性炭吸附剂应用于水中铀、钍的浓集进行了条件试验和验证，提出了适用于环境水样中铀、钍的浓集方法。结合不同分析方法的需要，对浓集于吸附剂上的铀、钍给出了用硝酸和盐酸两种体系的解析方法。结果表明，对２０Ｌ水样中的铀和钍均可达到９０％以上的回收，可以用于环境水样中铀、钍的浓集。     

DBN－偶氮胂在微量钍的分光光度测定中的应用

以ＤＢＮ－偶氮胂作为微量钍的分光光度测定的显色剂。结果表明，在１ｍｏｌ／ＬＨＣｌ溶液中，ＤＢＮ－偶氮胂和钍的络合物在λ＝６３０ｎｍ处的表观摩尔吸光系数为８．６×１０４Ｌ·ｍｏｌ－１·ｃｍ－１，并且可在高达９０倍的铀存在下测定微克级的钍。在０—１３μｇＴｈ／１０ｍｌ范围内符合比耳定律，标准曲线线性良好，相关系数ｒ＝０．９９９１。在３０％ＴＢＰ－煤油溶液中采用互溶法，可用ＤＢＮ－偶氮胂直接测定微量钍。采用乙二醇丁醚为互溶剂，显色剂和钍的络合物稳定性仍能满足要求，比耳定律适用范围不变，标准曲线线性良好。     

两例天然钍内污染案例的报道

本文报道了Y男、C男两例生前从事含钍纱罩生产的死者的职业史和发病史,对他们生前或死后的全身钍含量进行了测定和估算。按ICRP30和23号出版物的建议分别算得Y男全身钍含量为5.338mg,待积有效剂量当量为0.29Sv;C男全身钍含量16.61mg,待积有效剂量当量为1.00Sv,均未达到ICRP规定的限值。     

石煤（渣）和炭化砖中钍的测定

本文介绍了过氧化钠熔融样品，ＣＬ－ＴＢＰ萃淋树脂分离基体元素，铀试剂Ⅲ分光光度测定石煤（渣）和炭化砖中微量钍的方法。方法的最低检出浓度为６．４μｇ／Ｌ，全程回收率为９５．８％－１０４．０％，相对偏差小于１０％，对铀和其它元素有较好的分离效果。本方法的测定结果和γ谱仪测定值基本一致。     

上海纱罩厂部分职工体内钍含量调查

本文介绍了利用呼气中(气土)浓度测定法对上海纱罩厂部分工作人员体内钍含量进行调查的结果。调查人数为51人,其中行政人员6人,体内钍含量平均值为0.36Bq,与对照组0.33Bq 相比无显著差异;操作工人45人,平均值为1.65Bq,比对照组高4倍,最大值为8.35Bq,约高出24倍。还分析了呼气中(气土)浓度及体内钍含量与工种、工龄的关系,比较了呼气中(气土)浓度测定法与中子活化测定法的调查结果。     

用萃取液闪α谱分析法测定样品中的钍铀含量

介绍了采用萃取液闪与α谱分析相结合的方法来测定样品中的钍铀含量。结果表明：该法制样简便，对α粒子的探测效率为９８％，分析误差小于±５％，本底计数小于１０ｃｐｍ，最小可探测的样品量为５ｍｇ／Ｌ。     

用Ge(Li)γ谱仪快速测定气纱罩中非平衡态钍的含量

本文介绍用 Ge(Li)γ谱仪直接快速测定气纱罩中非平衡态钍含量的方法,主要叙述方法的原理以及对测量值的修正。本方法适用于大量样品的检查测定。     

钍铀燃料循环专用核数据库CENDL-TMSR-V1的基准检验

中国科学院上海应用物理研究所委托中国核数据中心研制了钍铀燃料循环专用核数据库CENDL-TMSR-V1，用于钍基熔盐实验堆的临界计算及屏蔽设计。为验证该数据库的可靠性，根据钍基熔盐实验堆的特点，从国际核临界安全手册中挑选了一系列基准实验装置进行基准检验。检验结果表明，绝大部分基准装置的k_eff计算结果与实验数据的相对误差在0.5%以内，证明CENDL-TMSR-V1具有较好的可靠性和适用性，可用于钍基熔盐实验堆的物理设计。     

用织纤布吸附快速测定钍废水中的α放射性

本文介绍一种快速监测钍废水中放射性核素浓度的方法。该法简单,其具体步骤是将一定大小的织纤布浸泡于废水中,搅动一定时间后取出,冲洗并烘干,即可直接测量。在一小时或更短的时间内便可得到结果。实验发现4号布对钍系有选择性吸附的能力。当废水中所含放射性核素以钍系为主时,所得实验结果与放化分析结果相差大约为10%,对含有少量铀的钍废水监测下限为10~(-11)居里/升。     

钍-铀燃料后处理中新萃取剂的研究——Ⅱ.亚砜类的研究及其结构与性能的关系

研究了5种亚砜类萃取剂在稀释剂(煤油及芳烃稀释剂)中的溶解性及对钍、铀的萃取性能。结果表明,二个具支链的烷基亚砜,即二(2-乙基己基)亚砜及二(1-甲基庚基)亚砜不仅与TBP一样可与煤油互溶,而且某些性能优于TBP。还对亚砜萃取剂结构与性能的关系作了初步探讨。     

Evaluation of uranium thorium and plutonium thorium fuel cycles in a very high temperature hybrid system

In recent times, there is a renewed and additional interest in thorium because of its interesting benefits. Thorium fuel cycle is an attractive way to produce long term nuclear energy with low radiotoxicity waste. In addition, the transition to thorium could be done through the incineration of weapons grade plutonium or civilian plutonium. Th-based fuel cycles have intrinsic proliferation-resistance and thorium is 3–4 times more abundant than uranium. Therefore, thorium fuels can complement uranium fuels and ensure long term sustainability of nuclear power.In this paper, the main advantages of the use of fuel cycles based on uranium-thorium and plutonium-thorium fuel mixtures are evaluated in a hybrid system to reach the deep burn of the fuel. To reach this goal, the preliminary conceptual design of a hybrid system composed of a critical reactor and two Accelerated Driven Systems, of the type of very high temperature pebble-bed systems, moderated by graphite and cooled by gas, is analyzed.Uranium-thorium and plutonium-thorium once-through and two stages fuel cycles are evaluated. Several parameters describing fuel behaviour and minor actinide stockpile are compared for the analyzed cycles.     

用三烷基氧膦(TRPO)从高放废液中去除锕系元素——TRPO有机相中锕系元素的反萃

研究了含锕系元素的30％TRPO-煤油负载有机相在硝酸、草酸和碳酸钠溶液中的反萃行为,给出了钢系元素的反萃条件。5—6mol/1硝酸能有效地反萃镅和镧系元素,过高的硝酸浓度下体系形成三相。0.5mol/1草酸二次错流反萃可回收99％以上镎和钚。5％碳酸钠可反萃铀。3个分组之间交叉沾污很小。提出了TRPO从高放废液中去除锕系元素流程简图。     

TEVA树脂分离-ICP-MS测量钍基体中微量铀

针对233 U提取工艺1AW钍基体中微量铀(m(Th)/m(U)=105)的分析,以TEVA树脂萃取色谱为主要分离纯化手段,以ICP-MS为测量手段,建立了一个简便快速的分析方法。上柱时模拟料液的体积为1mL、酸度为2.5mol/L,铀的洗脱液为12mL硝酸(2mol/L),方法对1AW模拟样品中铀的回收率为97.1%~100.0%,sr=1.1%(n=5)。该方法能够有效地将钍基体去除,从而实现微量铀的准确测量。     

The separation of Pa233 without a carrier from thorium nitrate preparations irradiated by slow neutrons

The article gives a method for the separation of Pa²³³ without a carrier from thorium nitrate irradiated by slow neutrons. Pa²³³ was extracted from a thorium nitrate solution by absorption on a precipitate of MnO₂, amyl acetate extraction of the cupferron complex of protactinium with subsequent re-extraction by a citric acid solution and, finally, decomposition of the citric acid complex by oxidation with concentrated nitric acid. During this process satisfactory removal of -and--radiation was achieved. The separated radioisotope was identified by determination of its half-life. The method developed is important for obtaining the radioactive isotope Pa²³³, without a carrier which can be used as an indicator for studying the chemistry of protactinium and also for solving problems of the extraction of protactinium from naturally occurring raw material and the separation of Pa²³³ from thorium during the preparation of U²³³.     

Actinide evolution and equilibrium in fast thorium reactors

The development of accelerator-driven sub-critical reactors operating with pure and enriched thorium fuel mixtures has been heralded as delivering a new era in sustainable nuclear power production. Many benefits have been claimed for these systems, particularly with respect to their ability to consume existing plutonium stockpiles and their inability to breed additional plutonium. This paper examines the operation of fast thorium reactors using a lumped model that can demonstrate to first-order accuracy the principles of actinide evolution and equilibrium and allow the identification of trends within the nuclide transformations. The fundamental mechanisms that affect nuclide evolution are demonstrated and the freedoms and constraints bounding this process are shown. Fast reactors operating with a 100% thorium fuel source are shown to generate plutonium and to offer no advantage over enriched thorium fuel in terms of actinide generation in longer-term operation.     

60MeV/u~(18)O离子同天然铀反应钍的放化分离

用１－苯基－３－甲基－４－苯甲酰基吡唑啉酮－５（ＰＭＢＰ）作萃取剂,２３４Ｔｈ为示踪剂,对在ＨＮＯ３介质中用ＰＭＢＰ－苯萃取钍的条件实验进行了研究。在条件实验的基础上提出了一个从中能１８Ｏ离子照过的天然铀样品中简便、快速地分离钍的化学流程。钍样品的Ｙ射线谱显示该流程能去除绝大多数产物元素,特别是Ｕ、Ｃｅ和Ｉ的沾污。     

Evaluation of implementation of thorium fuel cycle with LWR and MSR

In order to construct a sustainable society, it is necessary to consider fairness beyond generations and between countries. It is expected that Asian countries continue growing their economy and will result consuming more energy. More CO₂ emission is not acceptable.Nuclear power has many advantages for reducing CO₂ emission. However, it still has concerns of nuclear proliferation, radioactive waste and safety. It is necessary to overcome these concerns if nuclear power is expanded to Asian countries. Thorium utilization as nuclear fuel will be an opening key of these difficulties because thorium produces less plutonium, less radioactive waste. Safety will also be enhanced. The use of molten-salt reactor (MSR) triggered by plutonium supply from ordinary light water reactor (LWR) with uranium fuel will allow implementation of thorium fuel cycle with electricity capacity of about 446 GWe around at 2050.The other important sector in a view of sustainability is transportation. Transportation is essential for economy growth. Therefore it is inevitable to reduce CO₂ emission from transportation sector. Electric vehicle (EV) will be used as a major mobility instead of gasoline engine cars. Rare-earth materials such as neodymium and dysprosium are necessary for producing EV. These materials are expected to be mined from Asian countries. It is often obtained with thorium as by-product. Thorium has not been used as nuclear fuel because it is not good for nuclear weapon and it does not have fissionable isotopes. Recent global trend of nuclear disarmament and accumulation of plutonium from uranium fuel cycle can support starting the use of thorium.Thorium utilization will help both to provide clean energy and to produce rare-earth for clean vehicle. These will create new industries in developing Asian countries. An international collaborative framework can be established by supplying resource from developing countries and supplying technology from developed countries. “THE Bank (THorium Energy Bank)” is proposed here as one part of such a framework.     

低放废水处理系统的恢复改造与运行

本文简述了对某停运多年的低放废水处理系统进行恢复与改造的基本原则、主要内容以及系统经恢复改造后的工艺流程和主要优点。在恢复与改造过程中,保留原有的混凝沉降、蛭石吸附、离子交换等处理工艺,采用膜反应器技术进行固液分离及泥浆浓缩。系统经恢复与改造后,系统运行稳定、流程通畅、性能可靠,操作安全便捷、生产能力为0.74～0.8m³/h,达到恢复改造要求。低放废水经系统处理后,总α及总β的去除率分别为99.65%和98.20%,达标排放。