太原地区环境大气中氡及其子体浓度的日变化和年变化
Daily and annual variation of concentrations of environmental radon and its daughters in Taiyuan
这是子11月18日晚谈判破裂后,双方第一次坐下来进行正式对话。
This was the first time that the two sides had sat down for formal negotiations since talks broke down the night of nov.18 .