The task of designing porous materials for use in specific applications requires a detailed understanding of the adsorption process and how adsorption is affected by material properties. Applications of interest include maximizing gravimetric or volumetric adsorption capacity for hydrogen and carbon dioxide and increasing the selectivity for carbon dioxide in...
The adoption of surfactant replacement therapy (SRT) for the treatment of neonatal respiratory distress syndrome (nRDS) is one of the main contributors to the dramatic decline in infant mortality rates observed in the 1980s. Despite the significant efficacy of animal-derived surfactant preparations, there are still some concerns associated with their...
To increase the butanol titers and selectivity in <em>Clostridium acetobutylicum</em> we replaced the promoter of the alcohol/aldehyde dehydrogenase (<em>aad</em>) gene with the phosphotranbutyrylase (<em>ptb</em>) promoter and combined this with CoAT downregulation to minimize acetone production. This led to early production of high alcohol (butanol plus ethanol) titers and overall solvent...
Granular materials exhibit a wide variety of fascinating physical properties that can be observed both in nature and industry. The goal of this work is to better understand the flow, mixing, and segregation of granular materials in a prototypical system, the rotating tumbler, using numerical modeling, specifically, the Discrete Element...
Nature has been evolving innovative solutions to complex design challenges for billions of years, the success of which is evidenced by the myriad of life-sustaining systems that operate with unparalleled simplicity, efficiency, and durability. Biomimetic researchers derive inspiration from principles underlying natural phenomena to solve design challenges. This work is...
Natural tissues can have complex architectures characterized by the organization of multiple cells into structures, such as branching networks of the vascular or nervous systems. This cellular organization arises, in part, from spatial patterns in the expression of soluble factors, which create concentration gradients that direct cellular processes during morphogenesis....
Granular matter and living cells represent two extremes of what have come to be regarded as complex systems - systems characterized by a richness in global behavior that is not easily deduced from the interactions of their individual parts, even when those interactions are simple and well understood. On the...
The prediction of multicomponent adsorption equilibria from pure component data alone has been an active research area for over forty years. The Ideal Adsorbed Solution theory (IAS) has been the standard method of doing so, but contains an embedded assumption of Langmuir mixing. This assumption causes its predictions to be...
The recent tightening of permissible NOx release from diesel-powered engines has intensified the search for a catalytic system that can effectively remove NOx under challenging diesel exhaust conditions. Hydrogen-assisted selective catalytic reduction (H2-SCR) using supported palladium catalysts offers significant promise for lean NOx treatment due to its high activity at...
Two subjects are the focus of this dissertation: Au/TiO2 catalyst used for oxidation of CO at low temperature and siloxane nanocages, a novel material (~2nm) recently developed in our group
While bulk gold is chemically inert, gold supported as nanoparticles is remarkably active for the oxidation of carbon monoxide at...