An upper division undergraduate laboratory module to study Brownian motion was developed using polystyrene microspheres suspended in a sample liquid cell that was isolated from its surroundings. The dependence of the Brownian motion of the microspheres on their radius, the time, the viscosity of the suspension liquid, and the temperature were measured using a CCD camera interfaced with a frame grabber and a computer. The motion of each particle was monitored for 5 minutes and was found to be consistent with the Langevin formula for Brownian motion.

Gold and tungsten were deposited on silicon wafer and/or glass substrates by using random incidence sputtering deposition and thermal vapor deposition techniques. Two-dimensional tungsten nanotriangle and gold nanoring arrays were obtained on the silicon wafer substrate and examined using scanning electron microscope and atomic force microscope analysis. The size of the equal tungsten nanotriangles is within 100 nm per side and 210 nm apart from each other. The size of gold nanorings is 220 nm diameter, 40 nm wide, 10 nm thick, and 560 nm apart from each other. No nanorings were found on the glass substrate. Mechanisms for the formation of nanoring arrays are discussed.

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