英国哈维尔的放射性废物回取计划

【英国《国际核工程》2003年7月刊报道】 哈维尔(Harwell)的放射性废物回取计划包含一系列回取、重包装、水泥固化和贮存中放废物(ILW)的设备和设施项目。英国原子能管理局(UKAEA)希望在决定建造国家ILW处置库之前增建一座废物封装和处置厂,以完全固化核废物。 UKAEA最初除了负责许多不同类型的研究堆之外,还参与研发工作。哈维尔最后一座在役反应堆于1990年关闭后,其工作中心开始转向退役和废物管理。 因此,UKAEA已制订了一项放射性废物回取计划(AWRP)。AWRP是一系列处理地下贮存管中的ILW项目,其中包括对ILW进行回取、重…     

坑式废物库高水平放射性固体废物回取整备

某核技术利用废库（城市废物库）超期服役,设备老化,20世纪70年代因管理不规范而收贮的高放固体废物给周围环境带来极大的安全隐患,需尽快妥善回取、处置。中国原子能科学研究院放射性三废设施治理工程部根据现场实际工况,设计制订了利用“机器人-气帐”系统回取高放废物的工艺路线。通过现场污染水平和库坑“热点”检测分析,查找到了17号库坑内高放固体废物的具体位置。通过回取实施前的模拟验证试验工作,优化了回取的技术路线。采用远距离回取技术,成功地实施了高放固体废物的回取和包装整备工作。     

热室退役机器人研制及废物回取台架实验验证

101反应堆热室在退役过程中存在辐射水平高、空间小、环境复杂等难题，为完成热室内放射性废物回取等工作，设计一套退役机器人系统，以模拟热室台架为平台，开展废物回取实验验证。结果表明，机器人采用液压驱动方式，为双层滑台结构，具有6个自由度，在最大臂展情况下负载能力>30 kg。台架实验中，退役机器人的可达性较好，可实现储存井及热室地面散存废物的回取。退役机器人系统整体设计合理，功能满足热室退役要求，台架实验结果可为实际的工程实施提供技术支撑。     

英国原子能管理局从特劳斯菲尼兹的包封空间中回取废物

【英国《国际核工程》2000年2月刊报道】 英国原子能管理局(AEA)技术核工程部正在特劳斯菲尼兹从事两份重要的合同,其中包括设计和提供废物回取和包装设施,并进行操作。这两个项目是特劳斯菲尼兹电站退役计划的一部分。 第一个项目是回取以各种能动部件(MAC)形式贮存在位于1号和2号机组下方的处置室中的中放废物(ILW)。MAC废物流主要包括通量展平棒和导电弓架,但不包括从装料平台卸下的各种活化物项,例如热电偶和电缆。 第二个项目是回取以燃料元件碎片(FED)形式分别贮存在水池构筑物南端和北端的两个处置室中的ILW。FED废物流包括…     

法国圣戈班核子公司参与美国放射性废物回取项目

根据与Foster Wheeler环境公司签定的合同,法国圣戈班核子公司(SGN)在美国的子公司高杰马工程公司(CEC)将为从美国能源部的贮存设施中转移低放废物提供工程和技术支持。 该合同是为清理位于俄亥俄州的费尔纳德厂区而制定的加快放射性废物回取项目的一部分。该厂区以前被用于生产UO2,现在要正其进行清理,以用于工业或娱乐目的。 CEC将帮助设计废物传输系统,该系统用于从该厂区的两座料仓中回取废物,并它们运到中间贮存设施中。法国圣戈班核子公司参与美国放射性废物回取项目     

法国会通过高放废物处置库相关法律

正【欧洲核协会核新闻网(NucNet)2016年7月21日报道】法国国家放射性废物管理机构(Andra)近日表示,法国国会已通过一部有关高放废物最终处置库的法律,详细规定了拟建最终处置库即工业地质处置中心(Cigeo)的建设程序。根据这部国民议会2016年7月11日通过的法律,处置中心必须"可回取"。这部法律将可回取能力定义为使后代能够在下述两种方案间做出选择的能力:继续建设和运营处置库的后续工程,或者对以前的选择     

放射性废物收贮和流出物排放

1 放射性固体废物 2003年全院共收贮放射性固体废物11.6 m3,其中低放废物10.2 m3、中放废物1.4 m3,没有高放废物。收贮的上述废物主要有棉纱、手套、工作服、塑料布、玻璃器皿等。各单位送贮的放射性 固体废物具体情况列于表1。 表1 2003年放射性固体废物收贮情况     

美国废物超级压缩机运行长达10万小时

正【世界核新闻网站2017年8月7日报道】美国能源部(DOE)爱达荷(Idaho)场区的一座废物超级压缩机已运行长达10万小时。这台压缩机能够将55加仑(200升)的废物桶压缩至约11加仑(40升)。对废物桶进行压缩,能够减少将超铀废物从先进混合废物处理项目设施(AMWTP)运至墨西哥州废物隔离中间工厂(WIPP)的废物运输量。AMWTP主要用于对目前在爱达荷贮存的超铀废物进行回取、表征、     

3 放射性废物收贮和流出物排放

1 放射性固体废物,2004年全院共收贮放射性固体废物54．6m^3，其中低放废物54．2m^3、中放废物0．4m^3，没有高放废物。收贮的上述废物主要有棉纱、手套、工作服、玻璃器皿、污染设备等。各单位送贮的放射性固体废物具体情况列于表1。     

大型中放贮罐罐底放射性泥浆回取系统设计

本文针对大型中放贮罐罐底放射性泥浆放射性水平较高、泥浆板结及罐底存在加强筋等难点，设计了一套能够通过远距离操作自动投放至中放贮罐内对放射性泥浆进行搅拌、破碎及回取的系统和回取作业流程。     

Identification of radiation treatment of wheat （Triticum aestivum. L）and rice （Oryza sativa. L） samples using thermoluminescence of contaminating minerals

Food irradiation is gaining popularity worldwide and this technology is important to improve quality and reduce the post harvest losses of food. Because of the rapid commercialization of irradiated foods throughout the world, compliance of different regulations relating to use of technology in different countries and demand of consumers for clear labelling of irradiated foods, there is need for the development of analytical methods to detect radiation treatment of food. Among several methods studied so far, thermoluminescence （TL） is an important method that can be used to find out the irradiation history of food that contain even a very minute amount of dust particles. In this study, the irradiated and unirradiated wheat and rice samples were analyzed using the TL method. The samples were purchased from the local market of Peshawar and irradiated to radiation doses of 0.5 and 1.0 kGy using Co-60 gamma irradiator at the Nuclear Institute for Food and Agriculture （NIFA）, Peshawar. The mineral contaminants were isolated by jet water, ultrasonic treatment, and density gradient. TL glow curves of the isolated minerals from irradiated and unirradiated samples were recorded between the temperature ranges of 50-500℃ using a TL reader. Generally, the glow curves for irradiated samples showed much higher TL intensities （TL1） than the unirradiated samples. The results were normalized by rerradiation of mineral samples to gamma-ray dose of 1.0 kGy followed by determination of the second glow curves （TL2）. The ratio of the area of first glow curve to that of second glow curve （TL1/TL2） was calculated for selected temperature intervals and compared with the recommended values for unirradiated and irradiated samples. Finally, the shapes of the glow curves for irradiated and unirradiated samples were also analyzed. On the basis of these results （comparison of TL-intensities, TL1/TL2 ratios and shapes of the glow curves）, all the irradiated and unirradiated samples of wheat and rice were unequivocally identified.     

The preclinical pharmacological study of dopamine transporter imaging agent 18F-FP-β-CIT

The paper is to study pharmacologic characteristics of 18F-FP-β-CIT (18F-N-(3-fluoropropyl)-2β- carbomethoxy-3β- (4-iodophenyl)nortropane) as an imaging agent for dopamine transporter. The radiochemical purity of 18F-FP-β-CIT in aqueous solution was over 95% after standing at room temperature for 4h. Biodistribution displayed rapid uptake in rat brain (1.375 %ID/organ at 5min and 0.100 %ID/organ at 180 min) and the striatal uptake was 1.444,0.731, 0.397, 0.230 and 0.146 %ID/g at 5, 30, 60, 120 and 180 min, respectively. The values of striatum/cerebellum,striatum/frontal cortex and striatum / hippocampus in rat's brain at 30 min were 3.38, 2.17 and 2.40 respectively. The uptake in striatum can be blocked by β-CFT, suggesting that 18F-FP-β-CIT binds to DAT peculiarly. The compound was rapidly cleared from monkey's blood. The striatal uptake was bilaterally decreased in the left-sided lesioned PD rats, compared with normal control. Brain PET imaging studies in normal monkey showed that 18F-FP-β-CIT was concentrated in striatum. The test of undue toxicity showed that the dose received by mice was 1250 times as by human, which indicates that 18F-FP-β-CIT is very safe. So 18F-FP-β-CIT is a promising PET imaging agent for DAT with safety and validity.     

PLASMA SCIENCE AND TECHNOLOGY AUTHOR INDEX TO VOLUME 16(2014)

正~~     

Radioactivity levels in soil of salt field area,Kelambakkam,Tamilnadu,India

Soil samples in and around salt field area have been analyzed for natural radioactivity concentration using gamma ray spectrometer.The activity concentration for ~(232)Th,~(238)U and ~(40)K are ranged from 27.88 to 45.27 Bq/kg, from BDL to 13.30 Bq/kg,and from 135.54 to 381.28 Bq/kg,respectively.The measured activity concentrations for these radionuclides were compared with world average activity of soil.The average activity concentration of ~(232)Th in the present study is 1.19 times higher than world median value while the activity of ~(238)U and ~(40)K is found to be lower. The absorbed dose rates due to these radionuclides were calculated.The average absorbed gamma dose rate due to the presence of ~(232)Th,~(238)U and ~(40)K in soil samples is 36.99 nGy·h~(-1).These results indicate no radiological anomaly. The data presented in this study will serve as a base line survey for primordial radionuclides concentration in the study area.     

Non-FDG PET imaging of brain tumors

Due to relatively high uptake of glucose in the brain cortex, the use of FDG PET imaging is greatly limited in brain tumor imaging, especially for low-grade gliomas and some metastatic tumours. More and more tracers with higher specificity were developed lately for brain tumor imaging. There are 3 main types of non-FDG PET tracers： amino acid tracers, choline tracers and nucleic acid tracers. These tracers are now widely applied in many aspects of brain tumor imaging. This article summarized the general use of non-FDG PET in different aspects of brain tumor imaging.     

基于NPL-NMC系统的γ测量子系统的建模与优化

在军控核查中,核部件的质量、丰度、年龄属性需采用无损方法进行核查,NPL-NMC系统是一套利用中子多重性测量核部件质量属性的装置,为建立完善的属性测量系统,还需在NPL-NMC系统的基础上建立γ测量子系统。本文通过设计γ测量子系统在NPL-NMC系统上的布局及对中子屏蔽的优化,使系统能对铀部件的丰度、年龄属性进行测量。模拟计算结果表明,该γ测量子系统能很好地满足军控核查对铀部件丰度、年龄属性测量的要求。     

Improvement of carbon fiber surface properties using electron beam irradiation

Carbon fiber-reinforced advance composites have been used for structural applications,mainly on account of their mechanical properties.The main factor for a good mechanical performance of carbon fiber-reinforced com- posite is the interfacial interaction between its components,which are carbon fiber and polymeric matrix.The aim of this study is to improve the surface properties of the carbon fiber using ionizing radiation from an electron beam to obtain better adhesion properties in the resultant composite.EB radiation was applied on the carbon fiber itself before preparing test specimens for the mechanical tests.Experimental results showed that EB irradiation improved the ten- sile strength of carbon fiber samples.The maximum value in tensile strength was reached using doses of about 250 kGy.After breakage,the morphology aspect of the tensile specimens prepared with irradiated and non-irradiated car- bon fibers were evaluated.SEM micrographs showed modifications on the carbon fiber surface.     

Measurement system for SSRF pulsed magnets

This paper describes the magnetic field measurement system for pulsed magnets in SSRF.The system consists of magnetic probes,analog active integrator,oscilloscope,stepper motor and a controller.An application pro- gram based on LabVIEW has been developed as main control unit.After the magnetic field mapping of a septum magnet prototype,it is verified that the test results accord with the results of theoretical calculation and computer simulation.     

旁路阀调节对高温气冷堆闭式布雷顿循环瞬态特性影响研究

闭式布雷顿循环是第4代高温堆核能系统的关键技术之一,其典型的动态过程是旁路阀调节。为分析这一过程,建立了循环中关键部件的动态模型,其中压气机在径向平衡模型基础上耦合了对附面层发展的预测,兼顾了计算效率与准确性;换热部件模型基于双曲型守恒律方程,对工质的热物性和参数的快速变化有较好的适应性。在此基础上根据回路的质量守恒和压力平衡原则将各部件的模型耦合,建立了系统的动态模型。由于旁路阀调节是氦气透平发电系统主要的功率快速调节手段,瞬态效应较为显著,以模块式高温气冷堆（HTR-10GT）旁路阀开启后的过渡过程作为算例,分析了主要循环参数的响应特性,并通过分析,给出了降低输出功率的机制。计算结果表明：系统的容积惯性对旁路阀调节的响应速度影响较大,而阀门的开度则决定了系统在末态的输出功率;回热器的温度冲击现象可能发生在调节过程中,但可通过两旁路阀联动的方式缓解;反应堆出口温度变化幅度很小,因此反应堆模型的准确程度对结果基本无影响。     

CEFR 100%额定功率运行汽轮机发电能力分析

中国实验快堆(CEFR)首次100%额定功率发电运行中,实际电功率较设计值相差较多。为判断影响机组实际发电能力的主要原因,以现场采集的运行数据和汽轮机厂商提供的设计资料为基础,进行了相应的计算分析。对汽轮机内效率进行修正,绘制汽轮机近似热力过程曲线,并通过实测的各段抽汽压力,在热力过程曲线上获得抽汽焓值;利用换热器的能量守恒和流量守恒的基本方程进行除氧器和各加热器的热平衡计算,获得各段抽汽的流量;利用汽轮机的功率计算方程,得到汽轮机发电功率的计算值。通过计算值与实际值的比较分析,得出主蒸汽参数不达标是影响CEFR汽轮机发电能力的主要因素。