In human history, the spread of infectious diseases to mass numbers of people is not uncommon.

在人类历史上，传染病向大量人群传播的情况并不罕见。

And different isotopes have different mass numbers.

。 不同的同位素有不同的质量数。

This is a graph of the binding energies of various elements compared to their mass numbers.

这是各种元素的结合能与其质量数相比的图表。

We can describe how many protons and neutrons are in an atom’s nucleus using its atomic and mass numbers.

我们可以使用原子数和质量数来描述原子核中有多少质子和中子。

In alpha decays, the sum of the atomic and mass numbers are always equal on either side of the equation.

在 alpha 衰变中，等式两边的原子数和质量数之和始终相等。

Most of the world's poor are farmers, and so when farmers become more productive, then they earn more income, and mass numbers of people move out of poverty.

世界上大多数穷人都是农民，所以当农民变得更有生产力的时候，他们可以赚更多钱，很多人从此脱离贫困。

The Romans also invented the plantation, using mass numbers of slaves to work the land on giant farms called latifundia, so called because they were not fun.

罗马人还发明了种植园，使用大量奴隶在称为 latifundia 的巨大农场上耕种土地， 之所以这样称呼是因为它们并不有趣。

Any two nuclei that have the same atomic number but different mass numbers are known as isotopes, with most elements having one isotope that is more common than the others.

具有相同原子序数但质量数不同的任何两个原子核称为同位素，大多数元素具有比其他同位素更常见的一种同位素。