Natural background radiation

Conclusions The data presented show that the yearly background dose equals on the average about 2 mSv (200 mrem). Two thirds of the dose is attributable to internal radiation from natural radionuclides—primarily the decay products of radon and thoron, entering the human body with inhaled air. The external irradiation is due approximately equally to cosmic radiation and natural emitters such as⁴⁰K and radionuclides of the thorium and uranium series.Comparison with doses owing to the use of artificial radionuclide and other sources of ionizing radiation (Fig. 5) indicates that their contribution is insignificant. Amongst them diagnostic use of radiation (0.4 mSv) still predominates. The dose owing to nuclear tests in the atmosphere, which in 1963 reached approximately 7% of the average yearly dose owing to natural sources, is now less than 1%. The contribution of nuclear power in the first half of the 1980s did not reach 0.1% and, if forecasts of the growth of nuclear power are realized, by the year 2000 it will not exceed 1% of the background dose.Judging from reports by Soviet experts [7–9], the accident at the Chernobyl nuclear power plant will increase insignificantly the collective dose to the population of the European part of the USSR and will not affect the validity of the last conclusion: the dose due to nuclear power up to year 2000 will not exceed 1% of the background dose.Translated from Atomnaya Énergiya, Vol. 64, No. 1, pp. 46–56, January, 1988.     

辐射化学在辐射生物学发展和研究中的作用

辐射化学是连接辐射物理与辐射生物学的时空桥梁,其理论、模型和实验方法对促进辐射生物学的研究和发展起到不可缺少的重要作用。辐射诱导的化学变化不仅是辐射生物学效应的早期事件,在辐射诱导的DNA损伤与修复、生物辐射敏感修饰剂、辐射诱导的活性氧分子代谢和功能等研究领域都扮演重要角色。随着辐射生物学效应研究朝着系统辐射生物学方向发展,辐射生物学效应发生机理的精确研究和定量描述更需要辐射化学的方法和手段支持。     

聚合物的基本辐射效应辐射向聚合物的能量转移

聚合物的辐射交联、降解和接枝改性都是由辐射向聚合物的能量转移引发的.任何一种辐射源的辐射,都可以引发聚合物分子的活化或电离,生成发生化学反应所需的活性粒子.能量转移的主要形式是射线通过电离与聚合物分子发生作用,而碰撞的贡献比较小.X射线或γ射线等电磁波的辐射会产生高能二次电子,高能二次电子可以使聚合物分子发生电离.电子束、γ射线和离子束作为辐射源,其穿透聚合物材料过程中能量损失方式的宏观机理大相径庭.本文从宏观和微观两方面的机理分别对由电子、γ射线、离子和中子引发的单一辐射效应事件进行描述.     

Effect of the composition of radiation on the radiation damage to graphite

A statistical analysis is performed of the results on the determination of the critical neutron fluence in MR, SM-2, and BOR-60 with different irradiation temperature. It is shown that the critical neutron fluence depends not only on the irradiation temperature but also, and to an even greater extent, on the radiation composition factor (ratio of the neutron and γ-ray flux densities). Thus the critical neutron fluence for irradiation at 600°C in MR (radiation composition factor 0.13) is 17·10²¹ cm⁻² and in SM-2 (radiation composition factor 0.1) 11·10²¹ cm⁻² at the same temperature. When the same graphite is irradiated in the region of the outer corner of a working block of RBMK, where the radiation composition factor is 0.55, it is expected that the critical neutron fluence will be 31.7·10²¹ cm⁻². In summary, taking account of the effect of γ-radiation introduces substantial corrections: the experimental results obtained in research reactors are found to be at least a factor of 2 too low. This gives hope of substantiating the substantial increase in the service life of the RBMK graphite masonry. 3 figures, 8 references. Scientific-Research and Design Power-Engineering Institute. State Science Center—Scientific-Research Institute of Nuclear Reactors. Translated from Atomnaya énergiya, Vol. 87, No. 1, pp. 24–28, July, 1999.     

SDI—100辐射剂量仪

介绍了一种智能化的具有信号采集，数据处理及储存打印显示等功能ＳＤＩ－１００辐射剂量仪，该测量仪所用的探测器为微型半导体，测量精度为±０．０５％９ＳＤ），稳定度为±０．１６％（ＳＤ），可用在农用钴室，其它中小型＾６０Ｃｏ辐照源室以及放射治疗上。     

Modelling of radiation transport

In the application of nuclear radiation, the problem of the transport of photons and neutral or charged particles through the matter is central for understanding the physics of the process, for a correct interpretation of the measurement and for a convenient choice of instrumental operating conditions. This paper, in the first part, is intended as a survey of the genesis of the transport equations, which describe the phenomenon of the diffusion of the particles. With a regressive procedure, it is possible to obtain the commonly used transport equations directly from Liouville equation; the approximations that must always been involved can be related to two dimensionless parameters if suitable dimesionless variables are introduced. In the second part, approximate solutions of Boltzmann and Fokker–Planck equations are given for particular physical situations of interest in X-ray spectroscopy and electron microprobe analysis.     

新型航空辐射测量仪的研制

介绍了一种用于快速大面积辐射测量的仪器,该系统用于核爆炸及核事故应急监测。     

航空辐射监测研究

航空辐射监测是辐射监测的手段之一．它涉及多学科和多因素的影响．以近年的研究情况作一简述，重点是关键技术问题的研究和解决，系统的基本性能和测试结果等．     

Nuclear plant radiation inspection

Translated from Atomnaya Énergiya, Vol. 71, No. 3, pp. 242–244, September, 1991.     

Ion microbeam radiation system

An ion microbeam radiation test system has been built for studying radiation-induced charge collection and single event upsets in advanced semiconductor circuits. With this system, it is possible to direct an ion beam of a diameter as small as 1 μm onto a circuit or test structure with a placement accuracy of 1 μm. The components of the system and its operation are described. Applications are described which demonstrate the capabilities of the system