Extraction of Th（IV） from nitric acid with 40—benzoyl—2,4—dihydro—5—methyl—2—phenyl—3H—pyrazol—3—thione

The BMPPT(4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione)was synthesized from BMPP.Its m.p.is 106-108℃,The results of the element analysis are as follows:C,68.51%,H,4.51%,N,9.26%,S.11.47%,which are in conformity with the theoretical value(C,69.15%,H,4.76%,N.9.52%,S.10.90%),The solvent extraction of Th^4 from nitric acid solution by BMPPT in benzene was studied.The extraction ability of BMPPT is not so high as that of its parent (BMPP).The Th^4 distribution ratio(DTh)in creases with the increasing pH of the aqueous phase,and pH1/2 for Th^4 was 3.2([BMPPT]=0.10mol/L),When the pH increases,the distribution ratio of Th^4 increasdes linearly with the slope of 1.59,When the concentration of BMPPT increases,the distribution ratio of Th^4 increases rapidly.The lgDTh-lg[BMPPT]is linear with the slope of 1.42 and the extraction mechanism is the cation ion-exchange.     

SYNTHESIS OF THE RING—AND SIDE—CHAIN—~(14)C—LABELED 1,2—BIS—(4—MORPHOLINOMETHYL—3,5—DIOXOPIPERAZIN—1—YL) PROPANE

The ring-and side-chain-~(14)C-labeled probimane, 1,2-bis (4-morpholinomethy1-3,5-dioxopiperazin-1-yl) propane were synthesized from acetic acid-1-~(14)C in 4 steps and from ~(14)C-formaldehyde in 1 step respectively. The radiochemical yeild for the ring labeling was 28.1%; for the side-chain labeling was 18.5%.     

1—[2—^3H[（2—羟基—3—甲氧丙基）—2—硝基—1H—咪唑的制备

以ＮａＢ＾３Ｈ４还原１－（２－氧－３－甲氧丙基）－２－硝基－１Ｈ－咪唑制得１－「２－＾３Ｈ」（２－羟基－３－甲氧丙基）－２－硝基－１Ｈ－咪唑。产品经硅胶－Ｈ柱洗脱，蒸馏，Ｓｅｐ－Ｐａｋ Ｃ１８柱处理，并经ＨＰＬＣ及液闪检测，化学纯度〉９９．９％，放射化学纯度〉９７％，比活度为１６．０５ＴＢｑ／ｍｏｌ。     

EPR——欧洲压水堆

1 引言 2050年，地球上的人口将会达到80～100亿，与现在60亿人口的数字相对照，他们当中几乎有20亿人没有电力供应!能源需求将会相当大地增加，因为人类总是会自然地追求生活条件的改善，而且渴望均等共享经济进步带来的更多好处。     

超声波法合成2—^18F—2—脱氧—β—D—葡萄糖的初步研究

采用超声波法合成2-^18F-2-脱氧-β-D-葡萄糖（^18F-FDG）,以提高其合成效率。实验结果表明：F取代前体2位上亲核反应进行的程度与相转移催化剂和温度有关。无相转移催化剂时,84℃超声反应10min,亲核反应进行了70%;而在10mg的K2.2.2存在下,室温（22℃）下超声反应10min,亲核反应进行了85%,在84℃下超声反应2min,亲核反应进行了95%。同经典方法相比,超声波合成法^18F-利用率提高了10%,反应管的放射性吸附下降了5%。超声法合成效率（EOS）为60%,校正校率(EOB）为78%,合成时间为40min。仅用一根C-18纯化柱纯化,超声法合成的^18F-FDG中^18F^-含量低于1%。因此,采用超声波法合成^18F-FDG可明显提高合成效率。     

Overview of R&D activities on tritium processing and handling technology in JAEA

In JAEA, the tritium processing and handling technologies have been studied at TPL (Tritium Process Laboratory). The main R&D activities are: the tritium processing technology for the blanket recovery systems; the basic tritium behavior in confinement materials; and detritiation and decontamination. The R&D activities on tritium processing and handling technologies for a demonstration reactor (DEMO) are also planned to be carried out in the broader approach (BA) program by JAEA with Japanese universities. The ceramic proton conductor has been studied as a possible tritium processing method for the blanket system. The BIXS method has also been studied as a monitoring of tritium in the blanket system. The hydrogen transfer behavior from water to metal has been studied as a function of temperature. As for the behavior of high concentration tritium water, it was observed that the formation of the oxidized layer was prevented by the presence of tritium in water (0.23 GBq/cc). A new hydrophobic catalyst has been developed for the conversion of tritium to water. The catalyst could convert tritium to water at room temperature. A new Nafion membrane has also been developed by gamma ray irradiation to get the strong durability for tritium.     

压水堆3H源项计算分析

对压水堆中氚的产生和消减机理进行了研究。根据一回路冷却剂中氚的代谢机制建立氚计算模型,分析了压水堆各途径对氚的产生量贡献及⁷Li纯度对锂产氚量的影响。结果表明：计算模型详细考虑了产生氚的核素随时间的衰减变化,计算的氚产生量为52.08 TBq/a。压水堆一回路冷却剂中的氚主要来源于可溶硼的中子活化反应、铀核的三元裂变,对氚产生量的贡献达90%以上,⁷Li纯度为99.9%时锂产氚量占总量的7.45%,其他途径对氚的产生量贡献很小,可忽略。锂产氚量的贡献随着⁷Li纯度的升高而线性减小。研究结果可为压水堆氚源项的计算提供参考。     

便携式氚测量仪现场校准技术研究及装备研制

根据PV T方法研制了便携式氚测量仪现场校准装备.使用经检定的电离室装置对初始的氚气浓度进行了测量并作为校准装备的气源,根据PV T方法稀释配制了校准用的参考氚气,参考氚气浓度的不确定度为5.00％,满足EJ/T 1077-1998关于检验源的要求.使用放射性气体活度标准装置对配制的参考氚气进行了绝对测量,测量结果与理...     

压水堆主冷却剂中氚源项计算分析

压水堆主回路冷却剂流经堆芯时,水中固有及特加核素受中子辐照后会产生氚,氚几乎全部以气体和液体的形式排入环境,造成氚污染。因此,氚是压水堆辐射环境影响评价的主要关注内容之一。本文以AP1000为例,根据压水堆主回路冷却剂中氚的产生途径及其随时间的变化情况建立详细的计算模型,计算压水堆主回路冷却剂中的氚活度并分析各产氚途径对氚产生量的贡献。计算结果表明：主回路冷却剂中的氚主要来源于可溶性硼的中子活化和铀裂变,对氚产生量的贡献达80%以上;在⁷Li纯度为99.9%时,AP1000主回路中的年产氚量为5.23×10¹³ Bq,锂产氚量占总量的14.01%,随⁷Li纯度的增加,锂产氚量的贡献呈线性减小,在⁷Li纯度为99.99%时,锂产氚量占总量的3.18%。其他途径对氚的产生量贡献很小,可忽略。根据以上结果,可通过控制主回路冷却剂中添加的初始硼浓度、提高燃料包壳质量、增加LiOH中⁷Li的纯度等多种途径来降低主冷却剂中氚的产生量,从而减少氚对环境的放射性污染。     

Effects of internal bremsstrahlung of tritium β-decay and surface roughness in the BIXS method

We have studied the effects of the internal bremsstrahlung of tritium β-decay, sample surface roughness and tritium content as well on the tritium β-decay induced X-ray spectroscopy (BIXS) for tritium measurements based on Monte Carlo simulations. The Knipp-Uhlenbeck-Bloch theoretical model was adopted for the internal bremsstrahlung. It is found that the contributions of internal bremsstrahlung of tritium β-decays are approximately 30%, 10%, 4% and 2% of the corresponding external bremsstrahlung for C, Ti, Mo and W materials, respectively, and the sample surface roughness may cause an error of several percent in the BIXS method if the surface roughness of a sample is in a reasonable range. Moreover, the effect of tritium content should be taken into account when a sample contains a large amount of tritium, otherwise, the tritium contents measured by the BIXS method will be underestimated, for example, by up to ∼15% for Ti metal.     

基于BIXS方法的气体中高浓度氚在线测量技术

工艺气体中高浓度氚的在线测量要求探测器具有体积小、密封性好、稳定性高等特点.针对该需求,本工作基于氚β射线诱发X射线谱测量方法(BIXS)建立了高浓度氚在线测量实验系统,采用PENELOPE程序建立了理论计算模型,对系统中5个关键参数进行了设计优化,搭建了1.77 mL小体积BIXS实验系统,使用含氚的氢氩混合气体对实...     

Effect of sweep gas species on tritium release behavior from lithium titanate packed bed during 14 MeV neutron irradiation

In a fusion reactor, the prediction of tritium release behavior from breeder blanket is important to design the tritium recovery system, but the amount of tritium generated is necessary information to do that. Hence, tritium generation and recovery studies on lithium ceramics packed bed have been started by using fusion neutron source (FNS) in Japan Atomic Energy Agency (JAEA). Lithium titanate (Li₂TiO₃) was selected as tritium breeding material, and its packed bed was enclosed by the beryllium blocks, and was kept at certain temperature during fusion neutron irradiation. During irradiation, the packed bed was purged with the sweep gas continuously, and tritium released was trapped in each gas absorber selectively by chemical form. In this work, the effect of sweep gas species on tritium release behavior was investigated. In the case of sweep by helium with 1% of hydrogen, tritium in water form was released sensitively corresponding to the irradiation. This is due to existence of the water vapor in the sweep gas. On the other hand, in the case of sweep by helium without water vapor, tritium in gaseous form was released first, and release of tritium in water form was delayed from gaseous tritium and was gradually increased.     

Sorption of gaseous tritium on the surface of type 316 stainless steel

The sorption of gaseous tritium on the type 316 stainless steel was studied. The stainless steel was first contacted with gaseous tritium, and then the remaining tritium was evacuated. During a gradual etching from the surface by an acid solution, the tritium was released as HTO with a fraction of HT. They were radioassayed separately. The HTO mostly originates from the tritium present on the outer-most surface and about 90% of it could be released easily into water. However, the rest is sorbed tightly and remained in the surface layer. A fraction of the sorbed-tritium will diffuse atomically through the surface layer into the bulk of stainless steel and is released as HT by etching. The activation energy of the diffusion was determined as 32.8 kJ/mol.     

Production of 40 TBq Tritium Using Neutron-Irradiated 6Li-Al Alloy

A facility was reconstructed for producing tritium in 40 TBq per batch. Gaseous tritium was extracted from neutron-irradiated ⁶Li-Al alloy targets by heating at 700°C under vacuum and collected in uranium. The recovery yield of tritium was about 100% and the isotopic purity of the product was about 95%. Through the production run, no leakage of tritium from the facility was observed.     

电离室氚活度浓度标定及稳定性测量

电离室测氚在氚工厂、核聚变实验堆、环境监测以及各种涉氚实验装置中得到了广泛的应用.通过PV T法配制一定氚活度浓度的含氚气体,利用自主研制的流气式丝壁电离室实验系统,进行电离室氚标定实验,通过正交实验验证影响因素,从而完成对电离室的刻度.结果表明,该类电离室测量稳定性优异,相对偏差均小于1％,压力影响线性相关性均约为1...