羟基磷酸钙 ESR 信号热衰退中的二级动力学过程  

Second-order decay kinetics for the g=2.0018 ESR line of hydroxyapatite

作　　者：陈铁梅[1] 陈琪[1] 宝文博 吴恩[1] 

机构地区：[1]北京大学

出　　处：《核技术》1997年第8期455-459,共5页Nuclear Techniques

基　　金：国家自然科学基金

摘　　要：人工合成羟基磷酸钙和牙珐琅化石的等温退火实验表明，它们的ＥＳＲ信号的热衰退系一级和二级动力学过程的混合效应。二级衰退常数强烈依赖于温度，粗测其值在２８０℃时为１０－１９ｇ／ｓ量级。二级过程的存在对ＥＳＲ法测早期古人类遗址动物牙化石年龄的影响需进一步研究。The isothermal annealing experiments on synthetic hydroxyapatite and fossil tooth enamel samples show that the decay of its g=2.0018 line obeys the mixed first- and second-order annealing kinetics. The 2nd-order decay constant depends strongly on temperature and is roughly estimated to be about 10 -19 g/s for hydroxyapatite at 280℃. The effect of the 2nd-order annealing kinetics on ESR dating of ancient (early Pleistocene) fossil tooth enamel samples should be further studied.

关 键 词：电子自旋共振 羟基磷酸钙 热衰退 动力学 化石 

分 类 号：P597[天文地球—地球化学]