权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Development of wood materials as a radon sealant

开发木质材料作为氡气密封剂

基本信息

批准号：
07556041
负责人：
OKUYAMA Takashi
金额：
$ 6.08万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07556041/
关键词：
radon wooden materials radon sealant reduction rate of radon diffusion coefficient activated charcoal gypsum board interior materials ラドン拡散係数 MDF アクリル樹脂系塗料ラドン吸着室内放射能内装材木造住宅電離箱無機建材

项目摘要

Concrete and other inorganic construction materials emanate radon, which has radio-activity and stays in the air tightened room. It is said that people is affected by radioactivity and has a risk of lung cancer when they live in the room of a high radon concentrations for long time.The aim of this research is to seal the radon emanation from inorganic materials by using wooden materials as a radon sealant. It is expected that wooden materials reduce the radioactivity of radon during diffusing through wooden materials, because of its short half decay time of 40 minutes.Two methods were employed to evaluate the performance of radon sealant of wooden materials. A contract method ; As a sample block, an inorganic material board with high radon emanation were sandwiched with two wooden boards, surface to surface, and the edge was sealed with a glue. Radon concentration in a desiccator setting the sample block was monitored with a cup method. A non-contract method ; Radon concentrations was measured in the chambers separated by a sample board. Radon source was put in the one side of the chambers.As the results,1. Radon concentrations was reduced with the increases in the thickness of the sample. The order of the reduction rate from the highest reduction was soft wood plywood, lauan plywood, particle board and MDF.2. The reduction rate of MDF with 2.8mm thickness was 17% but the acrylic coating rose the reduction rate to 89%. 3. The wooden materials gave 7-30x10^<-5> cm^2/s as the diffusion coefficient of radon. 4. Charcoal reduces the radon emanation from the gypsum powder. The radon emanation of gypsum mixed with 15% of activated charcoal was reduced to 90%, and that of the mixture with charcoal of fir fiber was 70%.This study gave a possibility to develop a new interior materials which has high performance of radon sealant. Now we are evaluating the performance of the new gypsum board which was manufactured basing on this research.

混凝土和其他无机建筑材料会散发出氡，氡具有放射性，并停留在空气密闭的房间里。长期生活在高氡浓度的室内，人们会受到放射性的影响，并有患肺癌的危险，本研究的目的是用木质材料作为氡密封剂来密封无机材料的氡射气。由于氡在木质材料中的半衰期较短，仅为40 min，因此木质材料在氡的扩散过程中有望降低氡的放射性。合同方法;作为样品块，高氡放射性无机材料板夹在两块木板之间，面对面，边缘用胶水密封。用杯法监测放置样品块的干燥器中的氡浓度。一种非接触方法;氡浓度是在由样品板隔开的室中测量的。氡源放置在反应室的一侧。氡浓度随样品厚度的增加而降低。减量率从高到低依次为软木胶合板、柳安胶合板、刨花板、MDF.厚度为2.8mm的丙烯酸酯涂层的减少率为17%，而丙烯酸酯涂层的减少率提高到89%。3.木质材料测得氡的扩散系数为7- 30 × 10 ^<-5>cm ^2/s。4.木炭可减少石膏粉中的氡散发。在石膏中掺入15%的活性炭，可使室内氡析出率降低90%;在杉木纤维中掺入活性炭，可使室内氡析出率降低70%。目前，我们正在评估的新石膏板的性能，这是根据这项研究制造的。