FIGURE 3.2 Three-dimensional photonic crystals. These advances in three-dimensional photonic crystals, if reduced to practice, could pave the way to an amalgamation of microphotonic crystal devices with optical waveguides on chips for future optically integrated photonic circuits, computer, and telecommunication systems. a   Geoffrey A. Ozin, University of Toronto, presentation to Challenges for the Chemical Sciences in the 21st Century: Workshop on Materials and Manufacturing, National Research Council, Washington, DC, 2001. b   Y.S. Ming, and G.A. Ozin, “The Race for the Photonic Chip, Opal-Patterned Chips”, Adv. Funct. Mater., 11:1-10, 2001.

The current productivity of our agricultural enterprise would not be possible without the developments in fertilization, pesticides, and herbicides made by the chemical sciences. The unprecedented safety of our food supply is largely due to refrigeration (enabled by Freon^© and its more environmentally benign successors), clean food-processing conditions, and the development of new generations of packaging materials and technologies. Future developments may include the incorporation of sensors into packaging materials to indicate spoilage or unsafe storage conditions. Developing materials for such sensors and integrating them into packages, will involve the tailoring of materials at the molecular level to achieve the desired combination(s) of properties.