This project will study the fundamental science and practical engineering of liquids confined to spaces of the order of up to just a few nanometers in size. In view of current efforts to develop technologies based on micro- and nano-fluidics this type of understanding can be of immense practical importance. One example where the need for this knowledge arises is in connection with the developing 'lab on a chip' devices that promise to play an important role in medical and chemical science. When liquids are confined to spaces that are not much larger than the molecular size their physical properties are influenced by the properties of the surface. For example, the condensation of liquid within a small capillary occurs at different vapor pressure from condensation on a flat surface of the same material. The difference depends on the interfacial energy between the liquid and the capillary walls and this is precisely the reason why engineers commonly insert surfactants into oil wells in order to enhance secondary oil recovery from porous rocks. In this project we will study the fundamental processes that determine the liquid-solid interfacial energy. A special feature of this project is that we are able to manufacture macroscopic samples with controlled nano-scale features that make precision in-situ measurements of the properties of confined liquids feasible. In addition to the laboratory-based techniques such as laser feedback interferometry and confocal optical microscopy, this project will make extensive use of synchrotron x-ray and neutron scattering facilities at our national laboratories. The experiments will be complemented by theory and computer simulations. Students participating in this project will be well trained in the cutting edge research that this country is committed to. %%% Current efforts to develop technologies based on micro- and nano-fluidics promise to provide cost effect methods to deal with basic medical and chemical applications. For example, the often discussed 'lab on a chip' should make it possible to carry out both basic scientific experiments and practical diagnostic tests using only small amounts of fluids that would be either costly or dangerous if done with standard amounts. A real problem that these developments will encounter eventually is that the properties of liquids that are confined to spaces that are not much larger than the molecular size are often different than those of unconfined liquids. This occurs because of the increased influence of the surface on smaller samples. This project will use both modern laboratory-based techniques such as laser feedback interferometry and confocal optical microscopy, as well as synchrotron x-ray and neutron scattering facilities at our national laboratories to study the scientific and engineering properties of liquids confined to specially manufactured nano-scale structures. Students participating in this project will be well trained in the cutting edge research that this country is committed to. Thus, this project will satisfy the dual national goals of advancing our scientific/technological knowledge while simultaneously preparing the next generation of men and women for research in our countries laboratories. ***
