Chemicals giant DuPont de Nemours (DD -12.67%) is seeing demand soften, both from Western industrial customers and from China. That's impacting earnings, and investors are not happy.Shares of DuPont traded down 12% as of 10:30 a.m. ET Wednesday after the company released preliminary year-end results.Are DuPont customers scaling back?DuPont isn't scheduled to release final fourth-quarter numbers until Feb. 6. But on Wednesday, the company said it expects to earn between $0.85 and $0.87 per share in the quart ...