 AD stands for ANNO DOMINI which refers to Christ's birth. BC is before Christ. CE stands for 'Common Era' and is a recent term. It is used in place of AD.   BCD stand â¦ s for 'Before Common Day' and is used instead of BC, however it is more commonly represented as BCE, 'Before Common Era'.
Chemical engineers typically do the following: 1  Conduct research to develop new and improved manufacturing processes. 2  Develop safety procedures for those working with dangerous chemicals. 3  Develop processes for separating components of liquids and gases, or for generating electrical currents, by using controlled chemical processes.
Civil engineering is all about helping people and shaping the world. Itâs the work that civil engineers do to make our lives much easier. They keep us switched on and powered up by supplying electricity and gas to our homes. They give us clean water and purify it so we can use it again.