 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.
A chemical engineer can find employment with variety of companies, and despite the differences in the actual job duties, the job titles are often similar. Chemical engineers may be called process engineers, blending engineers or research engineers, for example. However, a blending engineer at a plastics manufacturer has different duties than one at an oil refinery, for example, so it is beneficial to examine what chemical engineers do in various employment settings.