Calcific aortic valve disease (CAVD) is a significant cardiovascular disorder characterized by the formation of calcific nodules (CN) on the valve. In vitro assays studying the formation of these nodules were developed and have led to many significant mechanistic findings; however, the biophysical properties of CNs have not been clearly defined. A thorough analysis of dystrophic and osteogenic nodules utilizing scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and atomic force microscopy (AFM) was conducted to describe calcific nodule properties and provide a link between calcific nodule morphogenesis in vitro and in vivo. Unique nodule properties were observed for dystrophic and osteogenic nodules, highlighting the distinct mechanisms occurring in valvular calcification.

The impact of alkalinity on the carbonation reaction in microconcrete mortars was assessed by evaluating the changes in the microstructure, solubility, and migration of major constituents (i.e., calcium, aluminum, and silicon), for cases of partial replacement of the Portland cement with different fly ashes having varying alkalinity. Several experimental techniques (i.e., SEM-EDS, U.S. EPA Method 1313, TIC, and TGA) were used and compared as tools to characterize changes due to the carbonation reaction. The rate and extent of carbonation was inversely related to the alkalinity of the material as evident by the increase in carbonation depth, reduction of the natural pH of the material, extent of the changes in the microstructure, and extent of reaction. Calcium migrated to the carbonated region while conversely silicon migrated from the carbonated region in response to relative solubility and therefore different diffusivity in the carbonated and uncarbonated regions for each constituent.

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Cast Stone has been developed to immobilize a fraction of radioactive waste at the Hanford Site; however, constituents of potential concern (COPCs) can be released when in contact with water during disposal. Herein, a representative mineral and parameter set for geochemical speciation modeling was developed for Cast Stone aged in inert and oxic environments, to simulate leaching concentrations of major and trace constituents. The geochemical speciation model was verified using a monolithic diffusion model in conjunction with independent monolithic diffusion test results. Eskolaite (Cr 2 O 3 ) was confirmed as the dominant mineral retaining Cr in Cast Stone doped with 0.1 or 0.2 wt % Cr. The immobilization of Tc as a primary COPC in Cast Stone was evaluated, and the redox states of porewater within monolithic Cast Stone indicated by Cr are insufficient for the reduction of Tc. However, redox states provided by blast furnace slag (BFS) within the interior of Cast Stone are capable of reducing Tc for immobilization, with the immobilization reaction rate postulated to be controlled by the diffusive migration of soluble Tc in porewater to the surface of reducing BFS particles. Aging in oxic conditions increased the flux of Cr and Tc from monolithic Cast Stone.