The bulk properties of materials are a superposition of the nanometer-scale properties of the material. To fully understand, manipulate, and engineer novel materials, methods must be developed which probe the electrical, mechanical, and magnetic properties with resolution on this length scale. Scanning probe microscopy has developed into a reliable, quantitative instrument for not only studying the localized properties of bulk materials, but for studying structures with dimensions on the micrometer scale. Dr. Schaefer.s research focuses on performing qualitative and quantitative measurements using scanning probe microscopy. Although a variety of experiments have been performed in his laboratory, the major focus of his research is the use of atomic force microscopy (AFM) to probe the interaction forces, adhesion, and mechanical properties of materials.

Participants in the REU program will learn to use scanning probe microscopes to study localized properties of materials. They will be involved in one of the following research projects over the three year program: 1) Particle adhesion plays an important role in the xerography, pharmaceutical, and paint industries. Many questions remain concerning the role and influence of factors such as humidity, surface roughness, and charge. In these experiments, micron size particles will be mounted onto AFM cantilevers and used to probe adhesive interactions. 2) An understanding of the germination of fungal spores with surfaces is important to develop successful inhibitors. By mounting a living fungal spore onto an AFM cantilever and bringing the spore into contact with surfaces, it is possible to study the removal force as a function of contact time. This data provides quantitative maps of the germination process. By then placing an inhibitor on the surface it is possible to quantitatively study the effectiveness of the inhibitor an develop better coatings to inhibit germination. These studies can be done as a function of environmental conditions and sample composition. 3) Biological organisms such as viruses and bacteria can form crystalline films on materials. These films exhibit the same structural imperfections (such as screw dislocations) as metallic films, however these films grow over much longer time scales. AFM will be used to study these films and study the localized mechanical properties of these films. Dr. Gail Gasparich, a molecular biologist in the Towson University Biology department, will provide biological support of this project. She will supervise the cultivation of microbes and processing of cultures used in these experiments.

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