Calcite and Aragonite
13C 18O Bonds in Precipitated Calcite and Aragonite: An ab Initio Study
... Figure 4. Comparison of the acid digestion fractionation factor y for (a) calcite and (b) aragonite for experimental fittings and theoretical results at temperatures from 0˚C to 50˚C. The legends are shown ...
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CALCINATIONS OF CYPRAEA MONETA (COWRY SHELL) LEADS TO PHASE TRANSFORMATION OF BIOGENIC ARAGONITE INTO CALCITE CRYSTALS
... 6. Shanmukhaprasad Gopi, V.K. Subramanian, K. Palanisamy, “Aragonite–calcite–vaterite: A temperature influenced sequential polymorphic transformation of CaCO3 in the presence of DTPA,” Materials Research ...
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Phase transformation of Mg calcite to aragonite in active forming hot spring travertines
... magnesium calcite to aragonite in a travertine crust ...of aragonite took place inside rather than on the surface of the rhombohedral polycrystalline Mg-calcite ...particles. Aragonite ...
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Influence of Mg2+, Fe2+ and Zn2+ Cations on 13C 18O Bonds in Precipitated Aragonite, Calcite and Dolomite: An ab Initio Study
... The interfacial clusters of carbonate groups on calcite (0001) surface, aragonite (001) surface and dolomite (0001) surfaces (Figure 1) were built with ab initio technique in Yuan et al. (2014). All ...
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Surface Modification and Planar Defects of Calcium Carbonates by Magnetic Water Treatment
... The calcite nanoparticles with negligible Fe 2? and Fe 3? impurities, as indicated by the same EDX spectrum (not shown) as that of aragonite, were typically agglomerated in a close packed manner and tended ...
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Polymorphism in biomineral nanoparticles
... of calcite and aragonite, ions or ion pairs were shown to break off the nanoparticles altogether (table ...The calcite example of 192 formula units (figure figure ...
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ΔGG of the vaterite and calcite phase.
... of calcite, aragonite and vaterite in CO-H2O solutions between 0 and 9OC, and an evaluation of the aqueous model for the system CaC03-CO2-H20, Gcochlmica ...
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Improving Recycled Fiber by Applying In Situ Aragonite Calcium Carbonate Formation Process
... The main sources of calcium carbonate are ground calcium carbonate (GCC) mined from calcite deposits and precipi- tated calcium carbonate (PCC) produced by means of a chemical reaction. PCC is an important ...
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Biomineral shell formation under ocean acidification : a shift from order to chaos
... newest calcite) and towards the newest aragonite formation (containing both newest aragonite and older cal- cite) was sectioned, and mounted in a resin block before polishing the cut edge of the ...
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Combining μXANES and μXRD mapping to analyse the heterogeneity in calcium carbonate granules excreted by the earthworm Lumbricus terrestris
... mainly calcite but can contain varying amounts of vaterite, aragonite and amorphous calcium carbonate (ACC) (Gago-Duport et ...of aragonite and Mg-calcite over calcite (Ries et ...
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WARM TO COLD WATER CARBONATE FORMATION DURING THE ORDOVICIAN AND THE JURASSIC: EXAMPLES FROM IRAN, AUSTRALIA, AND ENGLAND
... Aragonite or both aragonite and calcite can form at the same time in relatively similar tectonic settings. Examples include modern carbonate in Baffin Bay Texas [40], the Upper Jurassic Smackover ...
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Götz, Andreas (2011): On the Characteristics and Growth of Biominerals. Dissertation, LMU München: Fakultät für Geowissenschaften
... low-Mg calcite, a phase the is usually the end product of ...mineralise aragonite that is transformed to calcite during diagenesis and the high abundance of brachiopods throughout the Palaeozoic ...
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Enhanced Crystallographic incorporation of Strontium(II) ions to Calcite via Preferential Adsorption at Obtuse growth steps
... during calcite growth was found to affect the morphology of the resultant ...Sr-containing calcite can be produced at relatively high D Sr values in high throughput reactors across a broad range of Sr ...
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The amino acid composition of the organic matrix of some recent and fossil shells of some west coast species of Mytilus
... Comparison of certain amino acids in aragonite and calcite layers of shells of Mytilus californianus from Sonoma Coast, California... Comparison of certain am:no acids in aragonite and c[r] ...
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Effects Of Magnetic Field And Citric Acid On Polymorph And Morphology Of Calcium Carbonate Crystallized In A Flow-Water Pipe
... as calcite, aragonite, and vaterite ...stability, calcite is the most stable phase than others (i.e., aragonite and ...Particularly, aragonite and vaterite are less ...
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The role of Mg in the crystallization of monohydrocalcite
... some calcite or aragonite deposits found in the geologic record that have formed at high Mg/Ca ratios could be secondary in origin and may have originally formed via a ...
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Formation of Calcium Carbonate Polymorphs Induced by Living Microalgae
... polymorphs calcite, aragonite and vaterite in inorganic solutions has been the topic of many studies ...10. Aragonite preferably formed at pH 11; when the pH is higher than 12, calcite is the ...
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How Short-Lived Ikaite Affects Calcite Crystallization
... stable calcite (or aragonite) crystals, found in soils, sediments, biominerals or synthesised in industrial ...when calcite forms following the breakdown of ACC, it commonly shows spherulitic ...
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Is bicarbonate stable in and on the calcite surface?
... the calcite surface (Stipp and Hochella, 1991; Fenter et ...in calcite and the frequency of dislocations in the bulk and step edges on the surfaces, there is no shortage of defects in a real ...of ...
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The geology and mineralogical zoning of the H.Y.C. Ag-Pb-Zn deposit, McArthur River, Northern Territory, Australia
... Variation of the feldspar component and occurrence of calcite in the Lower Dolomitic Shale tuff, H.Y.C.. Variation of the feldspar component and occurence of calcite in the 2/3 interore [r] ...
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