论文部分内容阅读
传统的热释光(TL)测量技术面临着红外加热的热释光读出系统的竞争.为了成像,需要一种大面积的TL基质材料.以玻璃为基质的TL元件,难以承受激光加热速度快且又不均匀的热冲击.以聚四氟乙烯(PTFE)为基质的TL材料制成均匀的大面积的热释光剂量计比较困难,聚合物可以承受红外激光的高速聚焦加热.选择聚合物时要考虑的主要物理特性是材料对激光辐射的吸收和热扩散等.以CaSO_4:Mn作为热释光材料,聚偏氟乙烯(P-VF_2)为基质材料,二者混合可制成一种适于激光加热的TL材料——CaSO_4:Mn/PVF_2.其制备过程是:首先将PVF_2粉末按20～80%的比例放入N-N二甲基乙酰胺中溶解,同时在室温下用电磁搅拌器搅拌30分钟,然后将CaSO_4:Mn粉末(30～70%)加入PVF_2溶液中,再搅拌30分钟,最后将这种混合物倒入容器中在100℃下将溶剂蒸发.由于基质材料PVF_2的熔点为170℃,故须选择一种具有低温峰的TL材料.CaSO_4:Mn的发光峰中有一个70℃的低温
Conventional TL measurements are competing with IR-heated TL emitters. For imaging, a large area of TL matrix material is required. Glass-based TL elements are difficult to withstand the laser heating rate Fast and non-uniform thermal shock. PTFE materials based on the TL material uniform uniform large-area thermoluminescence dosimeter more difficult to withstand high-speed infrared laser focused polymer heating polymerization. Select Polymerization The main physical properties to be considered are the absorption and thermal diffusion of the material to the laser radiation, etc. CaSO_4: Mn as the thermoluminescent material and polyvinylidene fluoride (P-VF_2) as the matrix material, the two can be mixed to make one The TL material suitable for laser heating - CaSO_4: Mn / PVF_2. The preparation process is: first PVF_2 powder 20 ~ 80% of the proportion of NN dimethylacetamide dissolved, while at room temperature with electromagnetic stirring The mixture was stirred for 30 minutes and then CaSO 4: Mn powder (30-70%) was added to the PVF 2 solution and stirred for a further 30 minutes, and finally the mixture was poured into a vessel to evaporate the solvent at 100 ° C. Due to the melting point of PVF 2 Is 170 ℃, so choose a kind of low temperature peak TL material .CaSO_4: Mn emission peak in a low-temperature of 70 deg.] C