Examples abound of rings that feature multiple nitrogen atoms—the lightest of the pnictogen elements. There are triazoles, which snap together in the classic, copper-catalyzed click chemistry ...

The periodic table of elements (often known simply as the periodic table) has been helping scientists with their work for a little over 150 years. The handy visual reference guide organizes known ...

The hot image is printed first, followed by the cold image. (If necessary, additional ink can be applied to specific areas of the block to touch up the print.) The three prints the team used to ...