The crystallization of materials from a supersaturated solution is a fundamental chemical process. Although several very successful models that provide a qualitative understanding of the crystal growth process exist, in most cases the atomistic detail of crystal growth is not fully understood. In this work, molecular dynamics simulations of the morphologically most important surfaces of barite in contact with a supersaturated solution have been performed. The simulations show that an ordered and tightly bound layer of water molecules is present on the crystal surface. The approach of an ion to the surface requires desolvation of both the surface and the ion itself leading to an activated process that is rate limiting for two-dimensional nucleation to occur. However, desolvation on specific surfaces can be assisted by anions adsorbed on the crystal surface. This hypothesis, corroborated by crystallization and scanning electron microscopy studies, allows the rationalization of the morphology of barite crystals grown at different supersaturations.

CO2 and CH4 wettabilities of organic-rich shale are important physicochemical parameters that significantly influence CO2 sequestration and CH4 production. However, there is a serious lack of understanding of these aspects because the data available are scarce. Thus, we evaluated organic-rich shale CO2 and CH4 wettabilities (i.e., brine/shale/gas systems) through advancing and receding brine contact angle measurements as a function of pressure, temperature, salinity, and ion type (as these can vary significantly in underground formations). The results indicated that the brine contact angles for both CO2/CH4–brine–shale systems increased with pressure and salinity, but decreased with temperature. However, these effects were much less significant for CH4. Furthermore, the brine contact angles for the CO2–brine–shale system reached 180° (i.e., the shale was completely wetted by CO2) when the pressure reached 30 MPa at 343 K and ∼9 MPa at 298 K. The brine contact angles for the analogue CH4 systems was much lower (50°–90°), only indicating weakly water-wet to intermediate-wet conditions. Finally, the brine contact angles for CO2–brine–shale system were also larger for divalent ions (Ca2+, Mg2+) than for monovalent ions (Na+, K+), while ion type had no significant influence on CH4 wettability. However, a similar CO2/CH4 density resulted in a similar wettability. Consequently CH4 could not be used as a proxy for predicting CO2 storage capacities, unless they have similar densities.

This study utilized the Seahorse Analyzer to examine the effect of the bile acid ursodeoxycholic acid (UDCA), on the morphology, swelling, stability, and size of novel microencapsulated β-cells, in real-time. UDCA was conjugated with fluorescent compounds, and its partitioning within the microcapsules was examined using confocal microscopy. UDCA produced microcapsules with good morphology, better mechanical strength (p < 0.01), and reduced swelling properties (p < 0.01), but lower cell viability (p < 0.05) and cell count per microcapsule (p < 0.01). UDCA reduced the cells' biochemical activities, mitochondrial respiration, and energy production, post-microencapsulation. This is the first time biological functions of microencapsulated β-cells have been analyzed in real-time.

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