强源倒装中的安全防护与辐射监测

本文介绍上海辐射技术推广应用中心1986—1988年进行的三次强源(3.7—7.9×10~(15)Bq)倒装的操作程序、安全措施和倒源过程中的辐射监测。监测结果表明:运输铅容器表面的照射量率最大为17mR·h~(-1);工作人员在一次倒源操作中接受的剂量当量最大为9.1×10~(-2)mSv;钴元件污染或泄漏的放射性活度的检测值最大为42Bq/支,低于 ISO 规定的限值(185Bq/支);装源后辐照室周围环境的照射量率最大为17μ·h~(-1)。     

基于LoRa的γ辐射监测系统设计及应用

核能科学与技术和人们的生活联系紧密,但同时核辐射也可能危害人们的身体健康,因此需要加强对核辐射的监测。有线核辐射监测系统布线复杂、施工周期长、成本较高,且移动性差、故障排查较为困难。为了满足便捷测量γ辐射环境的需求,基于LoRa无线通信技术,设计了γ辐射监测系统。该系统的主要功能包括数据采集、数据处理及数据传输,采用硅光电倍增管（Silicon Photomultiplier,SiPM）闪烁体探测器进行数据采集,STM32单片机作为核心处理器对采集的数据进行处理、打包,由LoRa无线通信模块进行数据传输。针对可能存在的因复杂电磁环境、传输距离等因素导致监测系统断线及数据传输频繁时造成的区域内信道拥堵问题,设计了动态最优路径通讯算法,通过筛选中继节点,寻找最优重连路径以及实现数据发送的优先级分配。实际测试结果表明：闪烁体探测器测试辐射数据结果可靠,且基于LoRa的γ辐射监测系统数据传输稳定性达到99.57%以上。该系统具有组网灵活、传输距离远、成本低、拓展性强等优点,具有广泛的应用前景。     

核电建安工程辐射安全风险分析及管理实践

建立了核电工程施工领域射线探伤辐射安全故障树模型,采用故障树分析方法全面分析了射线探伤作业过程中发生辐射安全事件的风险。结合我国辐射防护相关法律、法规和标准的具体要求,参考Bechtel和FA3等公司的做法,按照作业工艺流程,制定了一套完整的核电施工现场射线探伤控制措施,从管理制度上和技术手段上杜绝安全事件的发生,规范核电工程施工领域射线探伤的辐射安全防护管理。     

基于EPICS的粒子加速器辐射安全联锁PLC系统设计

粒子加速器是一种研究粒子结构的高能物理研究装置,在加速器调试和运行过程中,会形成瞬发辐射,一套稳定可靠的辐射安全联锁系统是粒子加速器保护人员安全的必备设施.本文以高能同步辐射光源为例,介绍了一种基于EPICS的辐射安全联锁系统,该系统以横河PLC作为联锁控制器,可以保证系统的稳定可靠和可扩展性;用加速器控制行业十分流行...     

压水堆核电站α辐射的测量及防护

压水堆核电站发生燃料包壳破损时,可能会造成燃料从燃料组件释放到冷却剂中,其中以超铀元素为主的α放射性核素可能会引起系统、设备和工作现场的α污染,也增加了工作人员α内污染的风险。但由于这种情况发生的概率很低,所以一直以来核电厂对α辐射关注较少。本文介绍了法国电力公司(EDF)和(美国)电力研究院(EPRI)在压水堆核电站α测量和防护方面的要求和流程,针对国内核电站在α污染控制方面存在的问题,提出了改进建议。     

基于PET/CT中心的辐射监测及放射防护评价

PET/CT中心使用¹⁸F-FDG作为正电子放射性诊断药物,为此研究该中心的辐射水平,为临床辐射防护提供参考依据。利用X、γ辐射剂量率仪测量各工作区的辐射剂量率,利用热释光剂量仪估算工作人员的年有效剂量,并进一步研究了作为放射源的受检者离开前,周围人员与其保持不同距离时的辐射剂量率。结果表明:PET/CT中心各工作区及工作人员的辐射剂量符合国家标准。当周围人员与受检者保持3 m以上距离时,所测辐射剂量率近似环境本底值。     

医院核医学科辐射安全与防护管理应注意的问题及对策探讨

介绍了医院核医学科辐射安全与防护管理的特点与重要性,提出并分析了核医学科辐射安全与防护管理中的一些问题,主要涉及环境影响评价后置、布局和分区不合理、忽视自我辐射监测、加强“照射源”源头的管理等,探讨了相应的对策。     

γ射线辐照装置辐射安全与防护监督检查的思考

阐述和探讨了γ射线辐照装置辐射安全与防护监督检查中应注意的问题,为今后进一步深入监督管理提供参考意见。     

Radiation technology and environmental protection

Conclusion The examples examined here of using radiation technology to protect the environment were chosen as subjects of discussion only because they have already been tested in practice and have a high degree of engineering readiness for commercial introduction. There are also other fields for applying ionizing radiation to lessen the burden upon the environment. In particular, radiation technology makes it possible to solve the problem of cleansing industrial runoff of non-biodegradable detergents (up to 450 m³ of recovered water is subject to cleansing or dilution annually).It must be noted that the approaches discussed do not represent an attempt to artificially broaden the market for the nuclear industry. It is a matter of the considered usage of experience, equipment, and technology for solving problems on which, in the final account, the possibility of worthwhile existence for society as a whole and each individual in particular depends.In the next overview, it is planned to examine peak-wave treatment of food products and radiation sterilization of medical instruments in the context of reorienting the nuclear industry towards solving problems in the field of human health maintenance.IAEA Secretariat. Translated from Atomnaya Énergiya, Vol. 70, No. 5, pp. 354–357, May, 1991.     

ICRP Publication 105. Radiation protection in medicine

This report was prepared to underpin the Commission's 2007 Recommendations with regard to the medical exposure of patients, including their comforters and carers, and volunteers in biomedical research. It addresses the proper application of the fundamental principles (justification, optimisation of protection, and application of dose limits) of the Commission's 2007 Recommendations to these individuals. With regard to medical exposure of patients, it is not appropriate to apply dose limits or dose constraints, because such limits would often do more harm than good. Often, there are concurrent chronic, severe, or even life-threatening medical conditions that are more critical than the radiation exposure. The emphasis is then on justification of the medical procedures and on the optimisation of radiological protection. In diagnostic and interventional procedures, justification of procedures (for a defined purpose and for an individual patient), and management of the patient dose commensurate with the medical task, are the appropriate mechanisms to avoid unnecessary or unproductive radiation exposure. Equipment features that facilitate patient dose management, and diagnostic reference levels derived at the appropriate national, regional, or local level, are likely to be the most effective approaches. In radiation therapy, the avoidance of accidents is a predominant issue. With regard to comforters and carers, and volunteers in biomedical research, dose constraints are appropriate. Over the last decade, the Commission has published a number of documents that provided detailed advice related to radiological protection and safety in the medical applications of ionising radiation. Each of the publications addressed a specific topic defined by the type of radiation source and the medical discipline in which the source is applied, and was written with the intent of communicating directly with the relevant medical practitioners and supporting medical staff. This report consolidates that advice.     

The application of constraint based fracture mechanics to engineering structures

Elastic-plastic crack tip fields can be characterised by two parameters, J and T/Q which describes crack tip constraint. This forms the foundation of a constraint based fracture mechanics in which toughness is expressed as a function of constraint in the form of a J–(T/Q) locus. The enhanced toughness associated with shallow cracks and defects can be used in a systematic manner by constraint matching, and implemented through a simple modification to a failure assessment diagram. This methodology enables the conservatism associated with the use of deeply cracked fracture toughness measurements to be relaxed. In this work these methods have been applied to a tubular welded joint.     

超灵敏小型回旋加速器质谱计总体物理设计与束流规划

介绍超灵敏小型回旋加速器质谱计的总体物理设计与束流规划,描述14C粒子在SMCAMS中的分析过程.     

Vam3对小鼠体外胸腺细胞的辐射防护效应

探讨白藜芦醇二聚体(Amurensis H,Vam3)对辐射致小鼠胸腺细胞损伤的保护作用。体外无菌分离小鼠胸腺细胞,实验分为6组:对照组(Control)、白藜芦醇组(Resveratrol,Res)、Vam3组、照射组(Irradiation,IR)、照射+Res组和照射+Vam3组。照射+Res组和照射+Vam3组于照射前30 min给予Vam3和Res孵育,对照组、Res组、Vam3组以及照射组加等量RPMI-1640培养基或对应药物处理,除对照组、Res组和Vam3组外,其余3组均给予4 Gy ~(137)Cs γ-射线单次照射。照射后分别用生物发光法检测小鼠胸腺细胞活力,活性氧探针(DCFH-DA)检测细胞内活性氧(Reactive oxygen species,ROS)水平,荧光抗体标记检测γ-H2AX表达水平以及FITC-Annexin V和PI双染标记法检测细胞早期凋亡率。结果显示,与对照组比较,照射组细胞活力显著下降,细胞内ROS和γ-H2AX水平明显升高,同时细胞早期凋亡数目增加;而照射+Vam3组与照射+Res组比较显示,Vam3在提升细胞活力,降低细胞内ROS和γ-H2AX水平以及抑制细胞凋亡方面的作用比Res更加明显。研究结果表明,Vam3对辐射引起的小鼠胸腺细胞急性损伤有一定保护作用,且保护作用优于白藜芦醇。     

辐射防护仪表管理和维修总结

介绍了广东大亚湾核电站从投产以来．所使用的辐射防护仪表的品种和数量,回顾总结了多年来对仪表和设备的维修、检定、刻度和管理情况。并根据一些数据对仪表和设备的性能进行了分析和讨论。     

基于Oracle的高光谱数据管理平台设计与应用

高光谱遥感数据具有海量、高维、图谱合一等技术特点,随着数据量的增加,传统的文件管理方式越来越无法满足实际的需要。本文提出了将高光谱遥感数据按像元顺序或者波段顺序分割,按大型对象存储的技术思路,设计了高光谱遥感数据的存储结构,并开发了相应的数据管理平台。实际应用表明,该平台能够较好地完成高光谱数据的存储、管理与查询,取得了理想的应用效果。     

LiveWire程序的开发与应用

LiveWire是Netscape Web服务器特有的一种完成CGI功能的组件,通过LiveWire应用程序可以使网站动态生成网页。通过详细介绍LiveWire应用程序的源代码结构、编译、调试、管理与应用以及LiveWire应用程序的运行流程,说明如何创建LiveWire应用程序,以及如何在Netscape Web服务器上应用LiveWire应用程序生成动态网页。     

Radiation protection lessons learned from the TEPCO Fukushima No.1 NPS accident

Lessons learned from the TEPCO Fukushima No.1 NPS accident are discussed from the viewpoint of radiation protection in the situation of nuclear emergency. It became clear from the discussion that the protective measures should be practiced by taking into account the time profiles of the radiological disaster after the nuclear accident and that the land and coastal sea areas monitoring had to be practiced immediately after the nuclear accident and the communication methods to tell the public about the radiation information and the meaning of protective measures should be developed for mitigation of the sociological aspects of disaster impacts. And it was pointed out from the view point of practicing countermeasures that application of the reference levels, above which it was judged to be inappropriate to plan to allow exposure to occur, played an important role for practicing protective measures in an optimized way and that the quantities and units used for quantifying radiation exposure of individuals in terms of radiation doses have caused considerable communication problems. Finally, the occupational exposures and the public exposures that have been reported so far are shown, and it is concluded that there is no conclusive evidence on low dose exposures that would justify a modification of the radiation risk recommended by the International Commission on Radiological Protection.