The inorganic scaffold of the spicules, the skeletal elements of the calcareous sponges, is formed of calcium carbonate (CaCO3). The growth of the approximately 300-μm large spicules, such as those of the calcareous sponge Sycon raphanus used in the present study, is a rapid process with a rate of about 65 μm/h. The formation of CaCO3 is predominantly carried out by the enzyme carbonic anhydras...

Lime flocculation/sedimentation in the first process unit of a 4,500-m3/day wastewater reclamation plant reduced numbers of microorganisms extensively when operated at pH 11.2. The efficiency was much less at lower pH values, and some bacteria even multiplied at pH 9.6. Data on reduction in the number of microorganisms in the lime treatment and subsequent units indicate that inactivation by hyd...

The stable isotope and minor element geochemistry of Neocomian (Lower Cretaceous) pelagic carbonates of the North Atlantic Basin (Deep Sea Drilling Project Sites 105, 367, 387, 391, and 603) was examined to develop a diagenetic model for pelagic limestones. In particular, we hoped to test the fidelity of whole-rock geochemical records as paleoceanographic indicators for pelagic deposits of pre-...

We recently showed that the production of elemental sulphur and calcium carbonate (CaCO3) from gypsum waste by thermally reducing the waste into calcium sulphide (CaS) followed by its direct aqueous carbonation yielded low-grade carbonate products (i.e. <90 mass% as CaCO3). In this study, we used the insight gained from our previous work and developed an indirect aqueous CaS carbonation process...

Hierarchical nanoporous carbon (NPC) with great surface area and developed pore size distribution has been intently concerned. Herein, we report a facile method coupling template nanocasting and self-activation to fabricate nanoporous carbon with continuous micro, meso and macro pores, in which CaCO3 acted as template and activation reagent while the flour was the carbon precursor. Effects of m...

Acidification of seawater owing to oceanic uptake of atmospheric CO2 originating from human activities such as burning of fossil fuels and land-use changes has raised serious concerns regarding its adverse effects on corals and calcifying communities. Here we demonstrate a net loss of calcium carbonate (CaCO3) material as a result of decreased calcification and increased carbonate dissolution f...

Species richness (S) and frequency of invasion (IF) by boring sponges on living colonies of Pocillopora spp. from National Park Isla Isabel (México, East Pacific Ocean) are presented. Twelve species belonging to the genera Aka, Cliona, Pione, Thoosa and Spheciospongia were found, and 56% of coral colonies were invaded by boring sponges, with Cliona vermifera Hancock 1867 being the most abundant...

The characterization of corn starch (CS) films impregnated with CaCO3 nanoparticles was investigated. Criteria such as morphology, crystallinity, water vapor permeability (WVP), opacity, and mechanical properties were the focus of the investigation. It was found that the CaCO3 contents had significant effects on the tensile properties of the nanocomposite films. The addition of CaCO3 nanopartic...

Degenerate Clostridium beijerinckii strain (DG-8052) can be partially recovered by supplementing CaCO3 to fermentation media. Genome resequencing of DG-8052 showed no general regulator mutated. This study focused on transcriptional analysis of DG-8052 and its response to CaCO3 treatment via microarray. The expressions of 5168 genes capturing 98.6% of C. beijerinckii NCIMB 8052 genome were exame...

Properties of samples containing polyurethane (PU), poly(vinyl acetate) (PVAc) and nanosize particles of calcium carbonate (CaCO3) are correlated with concentrations of these components. Interphase phenomena in PU/PVAc/CaCO3 nanohybrids have been studied before, we focus here on wear and scratch resistance. In addition to polymer blends containing CaCO3, the effects of adding CaCO3 with grafted...