Can I promote my own content that I published on another Web site?

Yes, it is possible under the condition that you publish an article with a smart idea on this Web site. Your article could be a teaser getting readers interested in your content. The description of your idea(s) should be such though that the readers (with sufficient knowledge of the domain in question) should be able to apply the idea without the necessity to browse other links.
Your article can reference your content elsewhere on the Web that is related to the smart idea that you publish here. Preferably, put the links to your content in the References section of your article.