1. Based on the number set, a new commutative semi-group is established in the integer number and extended in number fields of rational number, real number and the complex number. 在数集的基础上，在整数域上建立了一个新的交换半群，并在有理数域、实数域和复数域上进行了推广；
2. Based on the number set, a new commutative semi-group is established in the integer number and extended in number fields of rational number, real number and the complex number. 在数集的基础上，在整数域上建立了一个新的交换半群，并在有理数域、实数域和复数域上进行了推广；
3. Vibration effects on the atomic clock (atomic frequency standard) could be divided into three parts: atomic resonance effects, crystal oscillator effects and servo-loop effects. 振动对原子钟（原子频标）的影响可分为对原子谐振的影响、对伺服环路的影响和对晶体振荡器（晶振）的影响。
4. They have the same atomic number and hence nearly identical chemical Behaviour But different atomic masses. 它们有相同的原子序数，因此化学行为几乎完全一样，但原子量不同。
5. Radium, atomic number 88, atomic weight 2260254, is a natural radioelement, elements were derived from Latin, is intended to "ray." 镭，原子序数88，原子量2260254，是一种天然放射性元素，元素名来源于拉丁文，原意是“射线”。
