ITER 试验包层模块活化计算与环境安全分析

运用聚变堆放射性计算程序FDKR 和衰变链数据库AFDC-DLIB, 计算了ITER 中国氦冷固态增殖试验包层模块设计中活化产物的放射性、衰变余热和潜在生物危害因子BHP 值。计算结果表明: 对于试验包层模块来说, 在500MW 聚变功率下运行一年, 停堆时的总放射性、余热和BHP 值分别为2. 10× 10¹⁶B_q 、5. 06 × 10^{- 3}MW 和 68. 6km³•( kW) ^{- 1}。结果表明: 中国氦冷实验包层模块不存在突出的安全问题。     

Study of the Wada fractal boundary and indeterminate crisis

By using the generalized cell mapping digraph (GCMD)method,we study bifurcations governing the escape of periodically forced oscillators in a potential well,in which a chaotic saddle plays an extremely important role.Int this paper,we find the chaotic saddle,and we demonstrate that the chaotic saddle is embedded in a strange fractal boundary which has the Wada property,that any point on the boundary of that basin is also simultaneously on the boundary of at least two other basins.The chaotic saddle in the Wada fractal boundary,by colliding with a chaotic attractor,leads to a chaotic boundary crisis with a global indeterminate outcome which presents an extreme form of indeterminacy in a dynamical system.We also investigate the origin and evolution of the chaotic saddle in the Wada fractal boundary particularly concentrating on its discontinuous bifurcations(metamorphoses),We demonstrate that the chaotic saddle in the Wada fractal boundary is created by the collision between two chaotic saddles in different fractal boundaries.After a final escape bifurcation,there only exists the attractor at infinity;a chaotic saddle with a beautiful pattern is left behind in phase space.     

核爆炸产物放射性衰变过程的研究

核爆炸后产物放射性和毒性及其随时间的变化是有关安全保障和环境保护的主要问题．利用新开发的数据库和程序对该问题进行了详细的理论研究,给出了裂变产物的放射性活度、生物潜在危害因子和能量沉积等量的演化情况,列出了主要放射性核的贡献,还分析了由于诱导反应在土壤和岩石中产生的放射性同位素的变化. The evolution of radioactivity and poisonousness of the products after nuclear explosion is very important for safety and environmental protection. The detailed study of the evolution of radioactivity of fission products, biological hazard potential, energy deposition and so on was performed by using the new data base and code. The contributions of the main radioactive nuclei and the evolution of radioisotopes in soil and rock are also discussed.     

酒与人类

酒与人类生活密切相关。本文从化学、生理学的角度介绍了酒的生产历史、生产过程,对人体和社会的危害及益处。     

山区铁路建设中的泥石流灾害与防治对策

在分析已建山区铁路泥石流灾害的基础上 ,指出我国中西部多数在建和规划铁路新线都将穿过泥石流强烈活动区 ,存在着少数泥石流沟难以避饶、部分低频泥石流沟难以判定、青藏高原及周边地区大型冰川和融雪泥石流可能造成铁路毁灭性破坏等重大技术问题 ,提出了改进铁路地质勘察方法、利用高新技术和组织专家对铁路建设中泥石流问题进行专门研究等对策。     

酸雨

本文介绍什么是酸雨,酸雨区的分布,酸雨中的主要成分及其前体物,酸雨的形成、输送和危害,以及人类的对策。