Microporous membranes were made and used to create new microstructures, composites, devices, and sensors. Nuclear track-etch membranes and anodic aluminum oxide membranes were used for the bulk of this work. Some of these membranes were custom fabricated as part of this work. Nuclear track-etch membranes were made at the Texas A&M University nuclear reactor by irradiation of thin mica sheets with uranium-235 fission fragments. A broad series of procedures and instrumental techniques were used to investigate the chemical and morphological characteristics of the membranes.; The pores of microporous membranes were used to grow various microstructures. This procedure is called template synthesis because the pores in the membrane act as templates for the microstructures. Metal microtubules, cadmium selenide and/or cadmium telluride microwire junctions, metal microfibers and substrates for surface enhanced raman scattering were fabricated by this method.; These microporous membranes were also used to prepare microhole array electrodes with one billion recessed microelectrodes per square centimeter. The electrodes that were made in this work have individual elements with submicron diameters. Some applications for electrodes of this type include convection-independent sensors and electrodes with a size-selective prefilter.; Finally, such microporous membranes were also used to mechanically support a very thin chemically selective non-porous membrane. This type of coated membrane combination is called an ultrathin film composite membrane. Ultrathin film composite membranes were prepared for pervaporation, biosensor, and other applications. The chemically selective "skin" of these membrane composites was generally less than one micron in thickness.
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