We reveal that the aragonite CaCO3 platelets in nacre of Haliotis laevigata are covered with a continuous layer of disordered amorphous CaCO3 and that there is no protein interaction with this layer. This finding contradicts classical paradigms of biomineralization, e.g., an epitaxial match between the structural organic matrix and the formed mineral. This finding also highlights the role of ph...

Experimental work involving artificial maturation of modern sediments was carried out to determine if diamondoids can be generated from biosynthetic precursors abundant in modern sediments. Mineral catalysts of distinctive properties, including montmorillonite K10, acidic aluminosilicate and CaCO3 were used in the hydrous pyrolysis of organic-rich modern sediments to examine which type of catal...

In this paper, two types of material forming filter cakes with different compressibility and compactness, namely CaCO3 and Kaolin were examined in a new test cell. Our measurements in the new test cell showed that C–P test data could predict reasonably well the actual filtration process. Taking into account the effect of side-wall friction, there were about 2–15 and 1–16% differences in average...

Mineral trioxide aggregate (MTA) cement is an attractive material in endodontic dentistry. The purpose of this study was to produce calcium silicate, which is a major component of MTA, from waste materials. A dental alginate impression gel and used chalks were selected and mixed in a suitable ratio (Code: EXP). As a control, CaCO3 and a commercial diatomite were used (Code: CON). Each powder wa...

Calcium carbonate (CaCO3) in the presence of single-walled carbon nanotube (SWCNT) /fullerodendron supramolecular nanocomposites was crystallized with a CO2 diffusion method under ambient conditions and in aqueous environments to produce monodisperse spherical SWCNT/CaCO3 hybrids with a core-shell structure. The crystals nucleate at the carboxyl groups on the surface of the SWCNT/fullerodendron...

Amorphous glassy CaCO3 colloidal spheres of monomodal size distribution were studied by high-resolution Brillouin light scattering. The Young modulus of 37 GPa and shear modulus of 14 GPa of glassy CaCO3 at a density of 1.9 g/cm3 were extracted from the particle vibration frequencies by employing acoustic wave scattering cross-section calculations. The line shape of the low-frequency modes is a...

Four self-assembled monolayer surfaces terminated with -COOH, -OH, -NH2 and -CH3 functional groups are used to direct the biomineralization processes of calcium carbonate (CaCO3) in low Ca(2+) concentration, and the mechanism of nucleation and initial crystallization within 12 h was further explored. On -COOH surface, nucleation occurs mainly via ion aggregation mechanism while prenucleation io...

In the brewing industry, spent brewery grains (SBGs) are byproducts with a low economic value. The potential use of this leftover as a substrate ingredient for Pleurotus ostreatus fruiting body cultivation and enzyme production was evaluated. The best substrate mixture for P. ostreatus mycelium growth comprised 30% wheat bran (WB), 68% beech sawdust (BS) and 2% CaCO3. On the substrates containi...

The crystallization of calcium carbonate (CaCO3) was investigated using a mineralization system composed of a chitosan membrane and regenerated silk fibroin (RSF). Such a system may resemble the mineralization in molluscs, where chitosan is a derivative of chitin and RSF an analogue of nacreous protein. It was found that the vaterite disks generally formed on the chitosan membrane while the ara...