One of the beauties of writing bylined articles is that you can leverage them. Here are some possibilities:
1. Reprints
2. White papers
3. Booklets
4. Speech outline and handouts
Reprints
Reprints are good things: they significantly increase your exposure to the market. Make sure you use the reprints anywhere you can including press kits, presentation handouts and conference take-aways. Post them on your site too. (Be sure to work out reprint rights with the publishing magazine beforehand.)
White Papers
Don't use the as-is published article as a white paper, articles are structured differently from white papers and you'll run into copyright issues. Instead use the article text to form the technology section of a white paper. Edit it to highlight customer benefits since you don't have to be vendor-neutral for your own white paper, and add white paper sections around it including executive summaries, problem statements, in-depth product/technology information, etc. (Click here for more information about writing white papers.)
Booklets
One of the best press kits I ever saw included a sharp and informative booklet on the vendor's technology. The booklet explained the general technology's development and background, presented the vendor's product, and listed clear customer advantages. It impressed both journalists and customers in a way a press release or even a white paper wouldn't have done. Booklets are labor-intensive, so use your trade journal article as the basis for writing your own.
Speech Outline and Handouts
Use existing articles as the basis for client speeches, presentations and handouts. Since trade journal articles are usually vendor-neutral, they'll work for conference talks too. When the presentation is about a product you can still use the article outline for the background technology and analysis then add product details, customer case studies, and Q&As.