Characterization of Liquid-Solid Reactions. Hydrochloric Acid-Calcium Carbonate Reaction

On the basis of magnesiothermy, with Mg powder, TiO2 powder and B2O3 powder as mixed reactants, relatively pure TiB2 powder was prepared by self-propagating high temperature synthesis (SHS) after leached in diluted hydrochloric acid with the suitable concentration. The product after leached was examined by XRD for qualitative and quantitative analysis, SEM for morphology analysis and infrared spectroscopy for transmittance analysis. It was found that diluted hydrochloric acid could decrease most of the impurities, and the proportion of TiB2 phase in the product is more than 99%, which was hexagonal shape crystal with the grain size of 200-300 nm. Compare with the infrared spectrogram of the middle infrared spectral region of the product of before and after acid pickling, it was found that the transmittance of TiB2 is extremely low in the range of 2000-4000 cm-1, which can be excellent infrared absorption material in the corresponding wave band.

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Preparation and characterization of three-dimensional chrysanthemun flower-like calcium carbonate

Journal of Wuhan University of Technology-Mater Sci Ed ◽

10.1007/s11595-012-0533-0 ◽

2012 ◽

Vol 27 (4) ◽

pp. 708-714 ◽

Cited By ~ 2

Author(s):

Xianyong Chen ◽

Qin Tang ◽

Daijun Liu ◽

Weibing Hu ◽

Youmeng Dan

Keyword(s):

Calcium Carbonate ◽

Three Dimensional

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Characterization of Limestone According to Geological Characteristics for the Synthesis of Precipitated Calcium Carbonate Powder

Proceedings of the 5th Asian Particle Technology Symposium ◽

10.3850/978-981-07-2518-1_358 ◽

2012 ◽

Author(s):

Seong-Young Nam ◽

Young-Joon Ahn ◽

Joobeom Seo ◽

Jin Kim ◽

Ji-Whan Ahn

Keyword(s):

Calcium Carbonate ◽

Precipitated Calcium Carbonate ◽

Geological Characteristics

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Preparation and characterization of phosphate-stabilized amorphous calcium carbonate nanoparticles and their application in curcumin delivery

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2020.123552 ◽

2020 ◽

Vol 255 ◽

pp. 123552

Author(s):

Chaohui Rao ◽

Min Li ◽

Xiaoqing Sun ◽

Meilin Li ◽

Xiaojie Lian ◽

...

Keyword(s):

Calcium Carbonate ◽

Amorphous Calcium Carbonate

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Luminescence reveals variations in local structural order of calcium carbonate polymorphs formed by different mechanisms

Scientific Reports ◽

10.1038/s41598-019-52587-7 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 6

Author(s):

Michael B. Toffolo ◽

Giulia Ricci ◽

Luisa Caneve ◽

Ifat Kaplan-Ashiri

Keyword(s):

Infrared Spectroscopy ◽

Calcium Carbonate ◽

Construction Materials ◽

Reference Database ◽

Formation Processes ◽

X Ray Diffraction ◽

Structural Order ◽

Lime Plaster ◽

Calcium Carbonate Polymorphs

Abstract In nature, calcium carbonate (CaCO3) in the form of calcite and aragonite nucleates through different pathways including geogenic and biogenic processes. It may also occur as pyrogenic lime plaster and laboratory-precipitated crystals. All of these formation processes are conducive to different degrees of local structural order in CaCO3 crystals, with the pyrogenic and precipitated forms being the least ordered. These variations affect the manner in which crystals interact with electromagnetic radiation, and thus formation processes may be tracked using methods such as X-ray diffraction and infrared spectroscopy. Here we show that defects in the crystal structure of CaCO3 may be detected by looking at the luminescence of crystals. Using cathodoluminescence by scanning electron microscopy (SEM-CL) and laser-induced fluorescence (LIF), it is possible to discern different polymorphs and their mechanism of formation. We were thus able to determine that pyrogenic calcite and aragonite exhibit blue luminescence due to the incorporation of distortions in the crystal lattice caused by heat and rapid precipitation, in agreement with infrared spectroscopy assessments of local structural order. These results provide the first detailed reference database of SEM-CL and LIF spectra of CaCO3 standards, and find application in the characterization of optical, archaeological and construction materials.

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