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The application of thermal lens calorimetry to the determination of the heat capacities of liquids has been reported in the literature. The accuracy is poor; a 60% error was reported for the heat capacity of methanol. This article describes a modified procedure that dramatically improves the accuracy of the method. A set of standard solutions was prepared from solvents of known heat capacity and the dye indophenol blue. The concentration of the dye in each solvent was adjusted to produce a solution with the same absorbance at 632nm, the wavelength of the laser used to perform the studies. These standards were used to produce a calibration line that allows one to systematically adjust the lens to sample distance and the size of the aperture in the diaphragm through which the laser beam passes. These adjustments are based upon the size of the thermal bloom produced as the laser beam passes through a sample. Standards were prepared from acetone, benzene, carbon tetrachloride, ethanol and methanol at three different absorbances. The calibration lines were used to determine the heat capacities of chloroform and toluene at each absorbance. The average relative errors for the heat capacities of chloroform and toluene were 3.0% and 2.6%, respectively.

The National Science Foundation-supported Materials Research Science and Engineering Center (MRSEC) on Nanostructured Materials and Interfaces at the University of Wisconsin – Madison has an extensive education and outreach effort. One theme of this effort is the development of instructional materials based on cutting-edge research in nanoscale science and engineering. The Nanoworld Cineplex contains movies and demonstrations that can be brought into classes, and the Nanotechnology Lab Manual contains numerous experiments that can be used for virtual or actual laboratories. Also available are kits, software, teaching modules and articles. A hands-on kit for nontechnical audiences, “Exploring the Nanoworld,” has been produced in collaboration with the Institute for Chemical Education.In this paper, novel hands-on demonstrations and innovative laboratory experiments aimed at the college level will be highlighted. High-tech devices and materials such as light emitting diodes (LEDs), shape memory alloys, amorphous metal, and ferrofluids are discussed in the classroom and studied in the laboratory as illustrations of nanotechnology and its impact on energy, the environment and our quality of life. These examples illustrate interdisciplinary research that provides connections among materials science, chemistry, physics, engineering, and the life sciences. They also highlight the tools of nanotechnology, such as scanning probe microscopy, electron microscopy, x-ray diffraction, and chemical vapor deposition, which are associated with the preparation and characterization of nanostructured materials. Demonstrations of the incorporation of nanotechnology to teach fundamental materials science principles presented are summarized at http://www.mrsec.wisc.edu/edetc.

The NSF-funded Internships in Public Science Education (IPSE) program at the University of Wisconsin-Madison (UW) provides a unique opportunity for undergraduate and graduate students with diverse academic backgrounds to experience learning and teaching sciencespecifically in the field of nanotechnology-to the general public and middle-school students. The program is a collaboration with Discovery World Museum of Milwaukee, Wisconsin, which provides expertise in public science education, access to local science teachers, and opportunities to test materials with a live audience. Since the program began nearly three years ago, UW IPSE interns have created a number of classroom activities ranging from understanding the scale of a nanometer, to experimenting with liquid crystal sensors, to critically examining the societal implications of nanotechnology. The program focuses on both the development of activity modules and the professional development of the interns. During activity development, intern teams learn about nanotechnology, gather background information, brainstorm ideas, present and receive feedback on their ideas, conduct experiments, build hands-on models, and create instructional materials to explain nanotechnology and related science concepts. During professional development, interns learn about creating classroom activities, techniques for presenting to non-technical audiences, and strategies for assessing their materials; and work on their skills in teamwork, project design, leadership, and science communication. In addition to visiting middle-school classrooms, interns participate in on-and off-campus informal science education events where they present to wider audiences ranging from science teachers, to members of the adult lay public, to groups of middle-school-age children. In this paper, we discuss the development, implementation, and assessment of the UW-Madison IPSE program.

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