 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.
Becoming an Engineer. 1  1. Study mathematics, science, and computer science in high school. 2  2. Participate in math contests and science fairs. 3  3. Develop hobbies related to mechanical engineering.  4. Learn to use different sorts of 1  tools. 5. Take stuff apart.