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Showing 1 to 20 of 234 for “"Calcium carbonate"”.
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Calcium carbonate precipitation kinetics
… and Reddy is presented to describe the rate of calcium removed from water in CacO3; precipitation. The mass of CaCO3; precipitated at any moment was obtained by monitoring pH and utilizing this in the equilibrium equations for the Ca - H2CO3 system including ion pairing and ionic strength …
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Investigating the redispersibility of calcium carbonate
The primary aim of this research was to investigate the redispersibility of the commercial calcite slurry product, Carbilux, after drying. Various dispersants and pH changes were made to improve the colloidal stability. The commercial product contained an unknown organic dispersant which was …
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The Mechanism for Calcium Carbonate Deposition in the Avian Eggshell
No abstract prepared.
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Microbial-Induced Calcium Carbonate Precipitation: from micro to macro scale
Microbial-Induced Calcium Carbonate (CaCO3) Precipitation (MICP) is a biological process in which microbial activities alter the surrounding aqueous environment and induce CaCO3 precipitation. Because the formed CaCO3 crystals can bond soil particles and improve the mechanical properties of soils …
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Aluminium foam production using calcium carbonate as a foaming agent
… large-scale production. The potential for metal carbonates as an alternative to currently-used titanium hydride foaming agents is explored, with calcium carbonate identified as the most suitable. The influence of a range of material and processing parameters on the stability of metallic foams in …
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Mica stabilization with lime, portland cement and lime-calcium carbonate
… of lime, Portland cement, and combinations of calcium hydroxide and calcium carbonate. In order to trace the calcium carbonate and calcium hydroxide in the stabilized soil, x-ray diffraction analyses, differential thermal analysis, and thermagravimetric analyses were made. Results show the …
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Reinforcement of Hydrogels via Polyacrylic Acid Nanoparticles Induced Calcium Carbonate Crystallization
… properties change after the addition of calcium ions and after the crystallization of CaCO3. The next system that was evaluated was the effect of both the nanoparticles and carboxylic acid functionalities on the hydrogel's material properties during every step of the crystallization …
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Admicellar Polymerization Of Calcium Carbonate And Its Performance In Drilling Fluids
… to form ultrafilm polystyrene on commercial calcium carbonate (CaCO3 ) of various particle sizes was studied. Adsorption isotherms of SDS decrease after the critical micelle concentration (CMC) of SDS was observed. This is explained by the phase behavior of SDS with calcium ion. The …
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Admicellar Polymerization to Compatibilize Calcium Carbonate With Oil-Based Drilling Mud
Weighting agents like calcium carbonate (CC) are added to drilling mud to improve mud properties and performance during oil and gas drilling operations. Oil-based mud (OBM), a more preferred drilling mud, being hydrophobic is particularly non-compatible with hydrophilic CC. This work explored an …
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Modeling Departures From Abiotic Expectations During the Calcium Carbonate Precipitation Process
… factors responsible for the formation of calcium carbonate (CaCO3) in natural systems, quantifying the extent to which biological influences drive precipitation in carbonate depositional environments remains an unresolved problem. Thus, a quantitative understanding of …
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Understanding ureolytic calcium carbonate biomineralization for crack repair in cementitious materials
… in the presence of nutrient medium with CaCl2 or calcium lactate but in absence of bacteria. Furthermore, calcium lactate was found to be a more effective calcium source than calcium chloride and cement paste powder for biomineralization. Urea was found to not only increase the extent of CaCO3 …
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The cleaning of copper leach solutions by means of calcium carbonate
Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Metallurgy, 1926 [first author], and Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrochemical Engineering, 1926 [second author].
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Stabilization of non-plastic soils with calcium hydroxide-calcium carbonate mixtures
The influence of calcium carbonate on the properties of four non-plastic lime-stabilized soils was studied. The four soils span a range in mica content and sand content. It was found that carbonate generally increased unconfined compressive strength and secant modulus of elasticity when included as …
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Carbon Sequestration Through the Production of Precipitated Calcium Carbonate From Waste Concrete
… production of synthetic limestone (CaCO3) from calcium silicate minerals and CO2 via mineral carbonation. Certain grades of CaCO3, including Precipitated Calcium Carbonate (PCC), are sold as a filler and pigment to several industries. Therefore, if marketable as PCC, the production of CaCO3 via …
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Nanoporous Calcium Carbonate-Based Substrates for the Controlled Delivery of Functional Materials
… of this project was to study `functionalised' calcium carbonates (FCCs) for use as a carrier for the controlled release of `actives,' by permeation and diffusion, and is being proposed as an environmentally friendly and non-toxic pharmaceutical excipient, nutraceutical, and flavour carrier. The …
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Calcium Carbonate Particle Size Effects on Titanium Dioxide Light Scattering in Coatings
… of TiO2 with cheaper material such as calcium carbonate (CaCO3), which serves to occupy volume.</p> <p>The purpose of this study was to compare the coating spread rate of paints with varying TiO2 and CaCO3 pigment volume concentration (PVC). Different sized CaCO3 particles were used in …
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Manufacturing bio-bricks using microbial induced calcium carbonate precipitation and human urine
… production as well as urea for microbial induced calcium carbonate precipitation (MICP) applications. MICP is a natural process that has the ability to produce bio-building material. Urine accounts for a small percentage of the total volume of domestic wastewater but contains a large percentage of …
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