Mahmoud K R
Physics and Chemistry Department, Faculty of Education, Kafr El-Shaikh University, Kafr El-Shaikh, Egypt.
J Radiol Prot. 2007 Mar;27(1):69-77. doi: 10.1088/0952-4746/27/1/004. Epub 2007 Mar 6.
The activity concentrations of natural and artificial gamma-ray emitting radionuclides in local and imported cement have been investigated during the period from 2000 to 2003 using a 50% HPGe gamma-spectroscopy system. The total numbers of local and imported samples were 29 and 8, respectively. The results showed a low activity concentration of (137)Cs in both the local and imported samples. The only exception was found in one imported Portland cement (2.8 +/- 0.2 Bq kg(-1)) and one local blast furnace slag cement (1.9 +/- 0.3 Bq kg(-1)). The average activity concentrations of (226)Ra, (232)Th and (40)K in local cement were 33 +/- 17, 14 +/- 2.4 and 45 +/- 26 Bq kg(-1), respectively, whereas those in imported cement were 27 +/- 7, 8 +/- 7 and 134 +/- 22 Bq kg(-1), respectively. The results showed that blast furnace slag cement contains the highest level of natural radioactivity, whereas white cement contains the lowest levels. The measured activity concentrations of the detected radionuclides were compared with other measurements carried out in Egypt and elsewhere. Radium-equivalent activities were also calculated to assess the radiation hazards arising from using such material in the construction of dwellings. Generally, the radium-equivalents of the analysed samples were smaller than the guideline limit of 370 Bq kg(-1).
2000年至2003年期间，使用50% HPGe伽马能谱系统对本地和进口水泥中天然和人工发射伽马射线的放射性核素的活度浓度进行了调查。本地和进口样品的总数分别为29个和8个。结果表明，本地和进口样品中（137）铯的活度浓度都很低。唯一的例外是在一种进口波特兰水泥（2.8±0.2 Bq kg⁻¹）和一种本地高炉矿渣水泥（1.9±0.3 Bq kg⁻¹）中发现。本地水泥中（226）镭、（232）钍和（40）钾的平均活度浓度分别为33±17、14±2.4和45±26 Bq kg⁻¹，而进口水泥中的平均活度浓度分别为27±7、8±7和134±22 Bq kg⁻¹。结果表明，高炉矿渣水泥的天然放射性水平最高，而白水泥的天然放射性水平最低。将检测到的放射性核素的测量活度浓度与在埃及和其他地方进行的其他测量结果进行了比较。还计算了镭当量活度，以评估在住宅建设中使用此类材料所产生的辐射危害。一般来说，分析样品的镭当量小于370 Bq kg⁻¹的指导限值。
