Engineering Commons^™

Engineered 3d Microenvironments To Direct Osteogenic Differentiation And Modulate Inflammation, Katherine Elizabeth Rutledge

Theses and Dissertations

Current methods of treating critical size bone defects (CSDs) include autografts and allografts, however both present major limitations including donor-site morbidity, risk of disease transmission, and immune-rejection. Tissue engineering provides a promising alternative to circumvent these shortcomings through the use of stem cells, three dimensional (3D) scaffolds, and growth factors. Cells receive signals from their microenvironment that determine cell phenotype, and a combination of physical cues and chemical factors is thought to have the most profound influence on stem cell behavior. A major focus of tissue engineering strategies is scaffold design to recapitulate in vivo microenvironmental architecture to direct stem …

Selective Synthesis And Characterization Of Single-Site Hy Zeolite-Supported Rhodium Complexes And Their Use As Catalysts For Ethylene Hydrogenation And Dimerization, Konstantin Khivantsev

Theses and Dissertations

Single-site Rh(CO)2, Rh(C2H4)2 and Rh(NO)2 complexes anchored on various dealuminated HY zeolites can be used as precursors for the selective surface mediated synthesis of well-defined site-isolated Rh(CO)(H)x complexes. DFT calculations and D2 isotope exchange experiments provide strong evidence for the formation of a family of site isolated mononuclear rhodium carbonyl hydride complexes (including the first examples of RhH complexes with undissociated H2 ligands): Rh(CO)(H2), Rh(CO)(H)2, and Rh(CO)(H). The fraction of each individual complex formed varies significantly with the Si/Al ratio of the zeolite and the nature of the precursor used.

HY zeolite-supported mononuclear Rh(CO)2 complexes are remarkably active in ethylene …