江苏省2011年环境γ辐射剂量率测量比对

为了保证辐射监测数据的准确,江苏省辐射环境监测管理站组织了2011年全省环境γ辐射剂量率测量比对。结果表明,22台仪器测量结果满意,1台仪器测量数据可疑,所有仪器均未出现不满意或离群结果。测量比对有效地发现了测量存在的问题,保证监测工作结果的准确性。     

上海黄浦江特定段水域放射性核素测定与评价

为了解上海黄浦江特定段水域放射性核素U、Th、²²⁶Ra、²¹⁰Po、²¹⁰Pb含量等信息,根据黄浦江特定段水域及其支流分布情况,使用三点采样法布设15个采样点,共采集15个样品,优化了样品的处理及测定方法,评价了特定段水域放射性核素的测定结果。结果表明:汛期放射性核素的测量值高于枯水期,U、Th、²²⁶Ra、²¹⁰Po、²¹⁰Pb的测量值范围分别为0.73~1.05 μg/L、0.32~0.57 μg/L、0.67×10^-2~0.95×10^-2 Bq/L、0.17×10^-2~0.37×10^-2 Bq/L、0.95×10^-2~1.31×10^-2Bq/L,年待积有效剂量约为0.012 5mSv,该剂量远小于标准限值。     

Radiological hazard assessment of natural gross radioactivity in some cosmetic products

Many kinds of cosmetic products were analyzed to determine gross radioactivity. In this study, gross alpha/beta radioactivity concentrations in 51 cosmetic samples were determined. The examined cosmetic products consist of blusher, eye shadow, lipstick, nail polish, shampoo, hand cream, cellulite cream, baby powder, soap, and toothpaste. The gross alpha–beta activity concentrations were measured with a nuclear spectroscopic system which contains gas-flow proportional counters. The highest gross alpha/beta activity concentrations were found in eye shadow samples of 1.621Bq g^?1 for alpha and 6.471Bq g^?1 for beta. The total effective doses due to gross radioactivity for skin were calculated. Although the effective dose of eye shadow samples had the highest value, the effective doses due to gross radioactivity concentrations in this study were found to be lower than the radiological limits given by the authorities.     

Development of inherent safety and health index for formulated product design

The numerous formulated products which are introduced to the market consist of chemical ingredients that may cause various safety and health hazards to the consumers. Therefore, it is extremely important to practice a systematic methodology to formulate products with acceptable safety and health performances. This work presents an index-based methodology to assess the safety and health hazards of the ingredients during the early formulation stage of product design. Hence, new inherent safety and health sub-indexes are introduced to improve the current safety and health hazards that are needed in formulated product design. The inherent safety and health sub-indexes are assigned with scores based on the degree of potential hazards. A higher score indicates a higher safety risk or severe health effect, and vice versa. The proposed methodology will greatly assist the users to identify the adverse safety and health effects caused by the ingredients. Hence, it is pivotal to eliminate or reduce the safety and health impacts from product usage. A case study on common ingredients used in the formulation of paint is presented on this study to describe the proposed method.     

Long term investigation of 137Cs in chicken meat and eggs from northwest Croatia

Abstract

This paper presents the results of long-term investigations of ¹³⁷Cs activity concentrations in chicken meat and eggs from northwest Croatia for the period 1987–2018. The research has been done as a part of monitoring program of radioactive contamination in Croatia. The highest activity concentrations in both of these foodstuffs were measured in 1987 and have been decreasing exponentially ever since. The Fukushima-Daiichi accident in 2011 did not cause any increase of ¹³⁷Cs activity concentrations. The ecological half-life for ¹³⁷Cs was estimated to be 8.0 and 8.4?years for chicken meat and eggs respectively. The correlation between ¹³⁷Cs in fallout and chicken meat as well as between ¹³⁷Cs in fallout and eggs is very good, the respective correlation coefficients being 0.79 and 0.72, indicating that fallout was the main source of ¹³⁷Cs contamination in both foodstuffs. The estimated effective doses received by adult members of the Croatian population due to the intake of radiocaesium by chicken meat and egg consumption for the overall observed period are very small, 2.0 and 0.6 µSv respectively. Therefore, chicken meat and chicken egg consumption was not a critical pathway for the transfer of radiocaesium to humans.     

对化学品登记要求的数据解释：皮肤致敏重复染毒及致变

本文对化学品登记所要求的部分健康效应数据——皮肤致敏、重复经口染毒、致变做了解释.涉及到的测试参数包括:皮肤致敏、重复(14/28天)经口啮动物毒性、基因突变、染色体畸变和DMA效应.     

新疆核试验场周围地区主要食品中90Sr(锶)、137Cs(铯)水平及其所致居民剂量

本文报道了新疆核试验场周围地区9个调查区17种主要食品中⁹⁰Sr、¹³⁷Cs含量分别为1.1~72.3,0.3~40.7×10^-2Bq·Kg^-1;3个对照区分别为1.6~68.4,0.6~27.4×10^-2Bq·Kg^-1。两地区同类食品中⁹⁰Sr、¹³⁷Cs平均含量基本一致。调查区⁹⁰Sr、¹³⁷Cs所致成年居民有效剂量当量值分别为2μSV(集体剂量当量为30.0人· SV);0.3μSV(4.5人· SV)。对照区分别为2.2μSV(集体剂量当量为20.9人·SV);0.4μSV(3.0人·SV)。可见我国核试验产生的⁹⁰Sr、¹³⁷Cs对核试验场周围地区食品没有造成明显的局部污染,所致居民剂量当量负担仅为我国天然外照射所致年有效剂量当量(952μSV)的0.2%和0.03%。对该地区的广大居民健康不会产生有害的影响。     

可重复使用航天器空间辐射效应评价关键问题及解决方法

介绍了可重复使用航天器及其应用需求,分析了其在太空遭遇的空间辐射环境及效应,探讨了可重复使用航天器的空间辐射效应评价在元器件退火效应研究及工程化、地面模拟试验设施及评价技术、地面检测维护及评价、抗辐射设计规范等方面存在的问题,提出了深入开展元器件空间环境效应及退火效应机理研究,给出适合可重复使用航天器的指标和评价体系;搭建多功能的综合环境效应地面模拟试验装置,加强多因素环境协同效应机理研究,建立空间多因素环境协同效应试验方法;开展空间环境多因素协同效应仿真,加强可重复使用航天器辐射效应预示方法的深入研究等解决途径。     

我国14种典型土壤脲酶、脱氢酶活性对汞胁迫的响应

Hg作为环境的主要污染重金属之一,其对土壤酶的影响是表征其环境效应的重要方面,结果可为土壤环境监测等提供生物学依据.因此,本文通过室内模拟试验,较系统地分析了全国14种主要类型18个土样的脲酶和脱氢酶活性在Hg胁迫下的响应.结果表明,Hg会抑制土壤酶活性,其降幅随土壤类型的不同有明显差异;随着Hg含量的升高,土壤脲酶和脱氢酶活性均显著降低;模型U=A/(1+B×C)可较好地拟合酶活性(U)与汞含量(C)之间的关系,揭示出土壤脲酶和脱氢酶在一定程度上可监测土壤Hg污染的程度,且机理为完全抑制(包括竞争性抑制和非竞争性抑制)作用.同时,实验获得的供试土样脲酶的生态剂量(ED10)范围为0.08~0.77 mg·kg-1,脱氢酶ED10范围为0.11~2.58mg·kg-1,从土壤酶角度获得的土壤汞轻度污染临界值为0.08 mg·kg-1,此值要小于国家土壤质量标准中的二级标准.有机质、pH、CEC和粘粒显著影响了汞与土壤脱氢酶的关系,上述4个土壤性状参数值越高,汞对土壤酶的毒害作用就越弱;酸性土壤中汞的毒害作用强于碱性土壤.表明在我国主要土壤类型上,土壤脲酶、脱氢酶对Hg毒性均较为敏感,可在更广范围内作为Hg污染程度的监测指标之一.     

辐射化学剂量计在强脉冲混合辐射场测定中的应用

本文讨论了将硫酸亚铁剂量计和铜－铁剂量计用于强脉冲混合辐射场测定的实验设计,利用直径２２０毫米的聚乙烯球,将硫酸亚铁剂量计的快中子响应降低到２０％以下,由它和完全暴露在中子、γ混合场中的硫酸亚铁剂量计响应之差,测量中子吸收剂量。这种方法两次实际用于强脉冲混合辐射场中子、γ吸收剂量测量,得到的结果和热释光剂量计、固体径迹探测器的测量结果进行了比较,在±２５％的误差范围内一致