内陆核电场址非人类物种辐射影响评价——参考生物的选择及应用

内陆核电建设对非人类物种电离辐射的影响逐渐为人们所重视,环境影响评价报告中对生物的辐射影响评价提出了明确要求。参考生物作为评估的基础,目前为止还没有明确的选择和确定方法。本文根据国内外对于参考生物的研究结果及选取准则,提出了参考生物的选择指标及方法,并应用于彭泽核电厂,初步确定了彭泽核电厂非人类物种电离辐射影响评估的一些主要参考生物。     

我国某核场址非人类物种辐射影响评价中陆生参考生物的选择

介绍了非人类物种辐射影响评价方法中参考生物的选择目的、准则等,选取了符合我国西南地区某核场址环境生态系统特征的多种陆生参考生物.参考动物包括鼠、鸟、蜜蜂,参考植物选取梧桐、柳杉、夹竹桃、荆条、野艾蒿,给出了上述各参考生物的生物学性状,为进一步评估其辐射剂量提供了重要的基础数据,最后给出此方面工作的建议.     

大亚湾周围海域几种水生生物的辐射剂量估算

提出了一个包括源项、照射途径、核素来源、剂量估算以及与释放限值比较等在内的非人类物种辐射剂量的评估框架;并选择大亚湾核电站所在的自然生态系统为研究对象,以对虾、黑鲷、毛蚶和小球藻4种水生生物为代表,建立它们的剂量学模型,并使用DOE GRADED和EU ERICA的非人类物种剂量计算软件以及Monte-Carlo方法对其剂量进行计算,对大亚湾的辐射环境提供评估参考。     

非人类物种的辐射生物效应研究

非人类物种的辐射生物效应可分为3类:早期死亡率、繁殖率降低和可记录DNA损伤.论文介绍了非人类物种辐射损伤的相似性、所受剂量的估算以及辐射生物效应,重点分析了电离辐射对陆生植物、陆生动物以及水生生物的辐射生物效应.为达到保护非人类物种的要求,建议在广泛调研国外非人类物种影响评价和管理的基础上,制定我国电离辐射非人类物种影响评价管理模式,研究我国现有辐射安全标准系统,探讨在那些标准中有必要增加电离辐射非人类物种防护的内容.     

非人类物种的辐射生物效应及其评价

简要介绍了非人类物种的辐射生物效应,并将其与人类的生物效应进行了比较。根据ICRP的有关出版物和其他资料,对防护人类和非人类物种的共同方法、已选定的参考动植物和参考剂量模式作了概要论述。     

非人类物种放射评价方法研究

介绍了非人类物种放射评价方法中选择参考动物和植物的目的和准则,重点对国外非人类物种辐射剂量率和辐射效应评估的两种主要方法即美国能源部(DOE)的GRADED方法和欧共体(EU)的FASSET方法进行了详细的分析和比较。在此基础上,提出了我国现阶段在非人类物种辐射剂量评估方面应该开展的工作和所要解决的难点,为我国下一阶段的非人类物种放射评估研究提供基础。     

R&D 128和ERICA模型在陆生生物辐射剂量估算中的应用研究北大核心CSCD

R&D 128和ERICA分别是英格兰和威尔士环境当局、欧共体推荐的估算非人类物种辐射剂量的模型。从陆生生物辐射剂量估算的原理、核素种类、参考生物种类、计算参数等方面对R&D128和ERICA进行了比较和分析,并利用两个模型对我国某AP1000核电厂周围陆生生物辐射剂量率进行了计算,最后对比分析了两个模型的计算结果和优缺点。     

非人类物种剂量评价低水平放射性测量的应用进展

介绍非人类物种剂量评价面临的挑战和低水平放射性测量对辐射剂量评估的重要作用,对四种常见低水平放射性测量方法和低水平放射性测量用于参考生物剂量评价的国内研究进展进行了概要论述,提出对未来非人类物种剂量评价研究方向的建议。     

ICRP第136号出版物:非人类生物种群环境照射剂量系数

正在开发和应用剂量学模型评估环境中放射源对动植物的照射时,非人类生物种群的多样性是一个具体的挑战。ICRP第108号出版物中采用的剂量学模型提供了一组参考实体(参考动物和植物即RAPs)的剂量系数(DCs)。该剂量系数可用于评估剂量和剂量率,并将后者与导出的考虑参考水平(DCRLs)进行比较。DCRLs是一组剂量率,其中在特定RAP中,如ICRP第124号出版物所描述的那样,在慢性、长期的辐射照射后可能会发生某种有害影响。     

R&D 128和ERICA模型在陆生生物辐射剂量估算中的应用研究

RD 128和ERICA分别是英格兰和威尔士环境当局、欧共体推荐的估算非人类物种辐射剂量的模型。从陆生生物辐射剂量估算的原理、核素种类、参考生物种类、计算参数等方面对RD128和ERICA进行了比较和分析,并利用两个模型对我国某AP1000核电厂周围陆生生物辐射剂量率进行了计算,最后对比分析了两个模型的计算结果和优缺点。     

百万千瓦级压水堆严重事故下局部隔间氢气风险分析

核安全法规要求控制严重事故下核电厂安全壳内的氢气浓度。除安全壳整体外,局部隔间的氢气浓度同样是关注的重点。本文采用一体化严重事故分析程序对百万千瓦级压水堆核电厂安全壳局部隔间进行建模,分析了不同事故下的氢气风险。结果表明,严重事故下部分隔间短时间内可能存在燃烧风险。本文对降低燃烧风险的方法进行分析计算和筛选,得出的结论可以为安全壳隔间的设计优化提供参考依据。     

ICRP Publication 114. Environmental protection: transfer parameters for reference animals and plants

In Publication 103 (ICRP, 2007), the Commission included a section on the protection of the environment, and indicated that it would be further developing its approach to this difficult subject by way of a set of Reference Animals and Plants (RAPs) as the basis for relating exposure to dose, and dose to radiation effects, for different types of animals and plants. Subsequently, a set of 12 RAPs has been described in some detail (ICRP, 2008), particularly with regard to estimation of the doses received by them, at a whole-body level, in relation to internal and external radionuclide concentrations; and what is known about the effects of radiation on such types of animals and plants. A set of dose conversion factors for all of the RAPs has been derived, and the resultant dose rates can be compared with evaluations of the effects of dose rates using derived consideration reference levels (DCRLs). Each DCRL constitutes a band of dose rates for each RAP within which there is likely to be some chance of the occurrence of deleterious effects. Site-specific data on Representative Organisms (i.e. organisms of specific interest for an assessment) can then be compared with such values and used as a basis for decision making. It is intended that the Commission's approach to protection of the environment be applied to all exposure situations. In some situations, the relevant radionuclide concentrations can be measured directly, but this is not always possible or feasible. In such cases, modelling techniques are used to estimate the radionuclide concentrations. This report is an initial step in addressing the needs of such modelling techniques. After briefly reviewing the basic factors relating to the accumulation of radionuclides by different types of biota, in different habitats, and at different stages in the life cycle, this report focuses on the approaches used to model the transfer of radionuclides through the environment. It concludes that equilibrium concentration ratios (CRs) are most commonly used to model such transfers, and that they currently offer the most comprehensive data coverage. The report also reviews the methods used to derive CRs, and describes a means of summarising statistical information from empirical data sets. Emphasis has been placed on using data from field studies, although some data from laboratory experiments have been included for some RAPs. There are, inevitably, many data gaps for each RAP, and other data have been used to help fill these gaps. CRs specific to each RAP were extracted from a larger database, structured in terms of generic wildlife groups. In cases where data were lacking, values from taxonomically-related organisms were used to derive suitable surrogate values. The full set of rules which have been applied for filling gaps in RAP-specific CRs is described. Statistical summaries of the data sets are provided, and CR values for 39 elements and 12 RAP combinations are given. The data coverage, reliance on derived values, and applicability of the CR approach for each of the RAPs is discussed. Finally, some consideration is given to approaches where RAPs and their life stages could be measured for the elements of interest under more rigorously controlled conditions to help fill the current data gaps.     

Modeling of radiation-induced bystander effect using Monte Carlo methods

Experiments showed that the radiation-induced bystander effect exists in cells, or tissues, or even biological organisms when irradiated with energetic ions or X-rays. In this paper, a Monte Carlo model is developed to study the mechanisms of bystander effect under the cells sparsely populated conditions. This model, based on our previous experiment which made the cells sparsely located in a round dish, focuses mainly on the spatial characteristics. The simulation results successfully reach the agreement with the experimental data. Moreover, other bystander effect experiment is also computed by this model and finally the model succeeds in predicting the results. The comparison of simulations with the experimental results indicates the feasibility of the model and the validity of some vital mechanisms assumed.     

Earthquake response analysis of reactor structures

The general nature of the principles upon which earthquake resistant design is based is described with particular reference to components and elements of nuclear reactor facilities. Special attention is paid to the response and design criteria of items of equipment or of components that are mounted on or attached to responding elements, and basic procedures are developed to bound the dynamic response of such items.

Consideration is given to vertical as well as horizontal excitation, and the combination of the effects of the various exciations. Suitable approximations are developed for inelastic response estimates.

One section of the paper is devoted to relative motions of points some distance apart, and to bounds for such relative motions.

Recommendations are made for the general criteria governing the design of nuclear facilities, including the basic parameters governing response characteristics and energy absorption.     

Preliminary definition of the remote handling system for the current IFMIF Test Facilities

A coherent design of the remote handling system with the design of the components to be manipulated is vital for reliable, safe and fast maintenance, having a decisive impact on availability, occupational exposures and operational cost of the facility. Highly activated components in the IFMIF facility are found at the Test Cell, a shielded pit where the samples are accurately located. The remote handling system for the Test Cell reference design was outlined in some past IFMIF studies. Currently a new preliminary design of the Test Cell in the IFMIF facility is being developed, introducing important modifications with respect to the reference one. This recent design separates the previous Vertical Test Assemblies in three functional components: Test Modules, shielding plugs and conduits. Therefore, it is necessary to adapt the previous design of the remote handling system to the new maintenance procedures and requirements. This paper summarises such modifications of the remote handling system, in particular the assessment of the feasibility of a modified commercial multirope crane for the handling of the weighty shielding plugs for the new Test Cell and a quasi-commercial grapple for the handling of the new Test Modules.     

海岛核电对岛屿非人类物种辐射影响及风险研究

海岛核电厂址是目前国内核电厂址选择的重要方向之一。《环境影响评价技术导则 核电厂环境影响报告书的格式和内容》(HJ 808—2016)中明确要求估算核电厂对非人类物种的辐射剂量。本文利用国内某海岛核电厂气态设计排放源项,采用ERICA程序,结合海岛生态本底调查结果,估算了核电厂气载放射性流出物对海岛生物的辐射影响和辐射风险,并进行了海岛生物的“三关键”分析。结果表明,核电厂对海岛各生物的辐射剂量率小于欧盟推荐的筛选值10 μGy/h,总体辐射风险较小。针对ERICA程序中部分参数(如剂量率转换因子和核素转移系数)的适用性问题,提出了今后须重点研究的方向。     

在冲击荷载作用下钢筋混凝土（RC）梁和板的冲击效应

这是一篇综合性的文章。它汇总了近年来一些研究工作者对钢筋混凝土梁和板在集中冲击荷载作用下的冲击效应进行研究所取得的一系列成果。这些成果可供有关工程人员应用或参考.