【作者】 唐柯鸿；

【导师】 王立军；

【作者基本信息】 清华大学 ， 核科学与技术， 2010， 硕士

【摘要】 随着科学技术的进步,同位素产品得到了越来越广泛的应用。同位素产品的获得依靠同位素分离技术。为了适应不同同位素产品的生产要求,过去一百多年内人们相继发展出了各种同位素的分离方法。传统同位素分离方法主要包括气体扩散法,气体离心法等。随后激光分离法的发展为人们提供了一种新型的高选择性,低能耗的同位素分离技术。本论文首先简要介绍不同种类同位素在科研生产各方面的应用,并对各种不同的同位素分离方法进行了比较。针对传统的激光同位素分离方法在分离某些元素时遇到的困难,俄罗斯的Bokhan等人通过研究发展出一种新型的激光光化学同位素分离方法,他们对此新型分离方法进行了分离实验,得到了比较理想的实验成果。在此基础上,Bokhan等人利用速率方程的方法建立了数学模型,对分离过程进行了一定的理论研究。本文对此分离方法的基本原理进行了研究,并阐述了Bokhan等人的实验和理论研究成果。本文接着分析了Bokhan等人建立的数学模型,认为在短脉冲激发条件下,模型中原子跃迁速率的计算方法存在一些缺陷。在对其数学处理方法进行修正的基础上,本论文重新建立了数学模型,并利用该数学模型对分离过程进行了分析,进一步研究了分离参数对分离过程的影响,并分析讨论了如何通过分离参数的调节对分离结果进行优化。更多还原

【Abstract】 Isotope products are widely used as science and technology advances fast nowadays. These products are produced by isotope separation techniques. In order to supply different kinds of isotope products, several isotope separation techniques are developed during the past century. Traditional isotope separation techniques include gas-diffusion, gas-centrifuge, etc., while laser isotope separation(LIS) method offers us a separation technique with higher selectivity and lower energy consumption. This thesis starts with some brief introduction to the application of different isotope products, and some compare of isotope separation techniques.Russian scientist P.A.Bokhan has developed a new photochemical isotope separation technique to solve the difficulties during the separation of certain elements using the traditional LIS techniques. They have brought out some experiments, and achieved good results. They have also completed some theoretical research with a mathematical model established on basis of rate equations. This thesis gives a description about the theory of this new separation technique and mathematical model developed by Bokhan. It is pointed out that some calculation methods in this model are not reasonable especially when duration of an exciting light pulse is short. Hence we obtain our new model by giving some modification to the previous one. This approach is then applied to research the process of this new separation technique and the impact of the separation parameters on the separation process and results.更多还原