[核]质量数（原子）

n.（原子）质量数

mass numbers───[核]质量数（原子）

class number───[数]类数；[计]分类号；[数]组数

class numbers───[数]类数；[计]分类号；[数]组数

magic number───[核]幻数，魔术数字

small number───n.[数]小数；少数交易

Mach number───马赫数（飞行速度除以音速）

back number───n.过期期刊；过时的人（或物）（等于backissue）

call number───呼叫号码；图书编目号码

car number───车牌号

isotope of hydrogen with mass number greater than 1; deuterium or tritium.───大于1的氢的同位素；氘或氚。

A radioactive isotope of cobalt with mass number '0 and exceptionally intense gamma-ray activity, used in radiotherapy, metallurgy, and materials testing.───钴的一种放射性同位素，质子数' 0，具有异常强烈的伽马射线作用，用于放射疗法、冶金和材料测试。

Bosons include mesons, nuclei of even mass number, and the particles required to embody the fields of quantum field theory.───玻色子包括介子、偶质量数的原子核以及体现量子场论中的场所需要的粒子。

Search the site to find in-depth information for the mass number of animals present all over the world.───搜寻网站上找到大规模的动物数量目前在世界各地的深度信息。

Chemical element is the general term for the same type of atoms with the same mass number.───化学元素是具有相同核电荷数的同一类原子的总称。

a uranium isotope with mass number 235; capable of sustaining chain reactions.───铀的同位素，原子质量数为，能进行持续的连锁反应。

In modern life, a mass number of people work day and night to seek wealth and as a result they do not pay much attention to their health.───在现代生活中，大量的人们白天工作并且晚上去放纵，并且作为结果他们忽视了他们的健康。

Hydrometeor mass, number, and space charge distribution in a "Hector" squall line───“赫克托”飑线的水凝物质量，数量和空间电荷的分布

Such current disturbs the zero out-put basic line of the light mass number region, so that it's very difficult to measure and record the height of spectrum peaks of the light mass number region.