Article Writing

I am in need of someone to write 3 articles each on three different topics. Th three for each topic may be similar in theory I jsut will be posting them in different venues so I want to avoid duplication. This person must be able to research and write clearly in the area of chemical engineering. The topics are: drum mixer sanitary mixer tote mixer All of these terms are in the area of industrial mixing, pharmaceutical...etc 500 words each.