A novel magnetorheological elastomer (MRE) mount is designed, fabricated, and tested to provide a wide controllable compression static stiffness range for protecting a system with variable payload from external shock and vibration. The shear static stiffness and compression dynamic stiffness were also studied. MRE is a field-controllable material in which the stiffness properties can be altered by changing the applied magnetic field. A MRE mount is developed by using 0.5-inch thick MRE layers and built-in electromagnets. The performance of the 2-layer MRE mount is characterized by compression, shear, vibration, and shock tests. The tests demonstrate that the variable-stiffness MRE mount can be used for shock and vibration isolation applications.

We present the mechanisms of formation of mesoporous scandia-stabilized zirconia using a surfactant-assisted process and the effects of solvent and thermal treatments on the resulting particle size of the powders. We determined that cleaning the powders with water resulted in better formation of a mesoporous structure because higher amounts of surfactant were preserved on the powders after washing. Nonetheless, this resulted in agglomerate sizes that were larger. The water-washed powders had particle sizes of >5 μm in the as-synthesized state. Calcination at 450 and 600 °C reduced the particle size to ∼1-2 and 0.5 μm, respectively. Cleaning with ethanol resulted in a mesoporous morphology that was less well-defined compared to the water-washed powders, but the agglomerate size was smaller and had an average size of ∼250 nm that did not vary with calcination temperature. Our analysis showed that surfactant-assisted formation of mesoporous structures can be a compromise between achieving a stable mesoporous architecture and material purity. We contend that removal of the surfactant in many mesoporous materials presented in the literature is not completely achieved, and the presence of these organics has to be considered during subsequent processing of the powders and/or for their use in industrial applications. The issue of material purity in mesoporous materials is one that has not been fully explored. In addition, knowledge of the particle (agglomerate) size is essential for powder handling during a variety of manufacturing techniques. Thus, the use of dynamic light scattering or any other technique that can elucidate particle size is essential if a full characterization of the powders is needed for achieving postprocessing effectiveness.

Current passive elastomeric mounts are designed to provide mitigation for a given shock and vibration exposure and are not capable of supporting variable payload systems, due to variation in the overall system dynamics. A novel magnetorheological elastomer (MRE) mount that can reduce or increase its stiffness based on payload and shock and vibration input is designed, fabricated, and tested to provide a wide controllable stiffness range for protecting sensitive systems that may require variable weight from external shock and vibration loading. A MRE is a field-controllable material in which the stiffness properties can be altered by changing the applied magnetic field. The two-way controllable MRE mount is designed by using threedimensional electromagnetic finite element analysis. MRE mounts were developed by using relatively thick MRE layers and built-in electromagnets and permanent magnets. A two-layer MRE mount prototype is characterized by compression and shear tests. Control system hardware and software were developed to detect shock and vibration events, and activate the two-way controllable MRE mount, accordingly. The MRE mount and the control system were tested with variable representative weights. It was demonstrated that the designed control system can detect whether the incoming input is a shock event or a vibration event. The MRE mount demonstrated the ability to soften of stiffen based on the incoming input.

Novel composite proton exchange membranes have been prepared from non-fluorinated polymer and non- and surface coated heteropoly acids (HPA) using atom transfer radical polymerization (ATRP). Polyether sulfone (PES) was used as a polymer matrix. Phosphotungstic acid (PWA), phosphomolybdic acid (PMoA) and silicotungstic acid (SiWA) were used as HPA. It was found that the SiWA has a higher conductivity compared with PWA, at the same concentration. PES was sulfonated using chlorosulfonic acid. The highest conductivity for sulfonated PES with 60 wt.% PWA was 1.7 x 10-2 S/cm. In order to increase the compatibility between SiWA and PES, the SiWA was surface coated. Surface coated SiWA particles can be added to the polymer matrix up to 50 wt.% to form a homogeneous membrane. This route also has the potential to increase the conductivity by sulfonation of grafted polymer backbone, and to avoid "washing out" of HPA in the fuel cell.