1)atomic element,原子元素2)intermediate element,中等原子量元素3)heterobar['hetərəbɑ:],异原子量元素4)daughter atom,继承元素的原子5)atomic structure of heavy ion,重元素原子核结构6)the first spectrum of uranium,铀元素原子第一光谱
用法例句
So far,as an examp1e, many energy levels in the first spectrum of uranium (U I) have not been classified definitely according to their electronic configurations.
