The observed good fluoride removal has been attributed to a combination of two mechanisms of fluoride removal, viz., precipitation of calcium fluoride and adsorption of fluoride ions on limestone ...

Abstract. Raman scattering from a high purity calcium fluoride crystal excited by a 6328 Å He-Ne laser has been observed. Contrary to results reported by Russell, no Raman structure was observed except for the first order line at 322 cm -1.The strong spectrum, reported by Russell as second order Raman scattering, is found to closely resemble the …

Abstract We discuss the intrinsic birefringence of calcium fluoride and othercrystalline materials that may be used in the optics for 193nm and 157nmlithography, including the characterization of the effect and itsimplications for performance of lens systems at these wavelengths. Wediscuss and assess the approaches by the lithography …

Abstract. The utilization of waste perlite powder generated from mining operations in the construction industry represents a significant step towards enhancing environmental sustainability. ... Additionally, the research explores the influence of calcium fluoride and silicon carbide on the ing properties of materials under varying …

Excessive fluoride mainly causes skeletal lesions. Recently, it has been reported that an appropriate level of calcium can alleviate fluorosis. However, the appropriate concentration and mechanism of calcium addition is unclear. Hence, we evaluated the histopathology and ultrastructure, DNA fragment …

Abstract. Acid resistance zeta potential and ESCA (electron spectroscopy for chemical analysis) experiments were performed on emperador marble and four calcium carbonate samples (onyx calcite, travertine calcite, Iceland spar calcite and aragonite). Six fluorine-containing reagents were used to treat the surfaces of these materials: …

For the formation of solid calcium fluoride the source of calcium may be either the enamel itself or remaining saliva or--in plaque--plaque fluid and calculus. The aim of the present study was to examine whether saliva through its calcium content has any influence on the amount of calcium fluoride formed by a topical fluoride treatment of enamel.

Abstract: A process is disclosed for producing calcium fluoride. The process comprises (a) mixing phosphate rock with aqueous H 2 SiF 6 at ambient temperature for at least one hour; (b) nucleating the calcium fluoride in the slurry prepared in step (a) by reacting the slurry at a temperature and for a time sufficient to initiate and sustain ...

Abstract. All currently used topical fluoride agents deposit soluble fluoride as calcium fluoride on enamel or in lesions. Calcium fluoride serves as a source of fluoride for the …

Calcium fluoride in demineralized bones from rats with experimental chronic fluorosis. Lindemann G. Scandinavian Journal ... To arrive at the top five similar articles we use a word-weighted algorithm to compare words from the Title and Abstract of each citation. Calcium fluoride containing granules produced in vitro in rat bones. ...

Abstract. Calcium fluoride is a dielectric material with a wide bandgap (∼12.1 eV) and a relatively high dielectric constant (∼6.8) that forms a van der Waals interface with two-dimensional (2D) materials, meaning that it contains a very low …

Abstract A calcium precipitating and denitrifying bacterium H12 was used to investigate the F-removal performance and mechanism. The results ... Under the induction of bacteria, calcium, fluoride and phosphate coprecipitated to form Ca 5 (PO 4) 3 F and CaF 2. In addition, the gas chromatography data indicated that F ...

Abstract: Magneto-plasticity occurs when a weak magnetic field alters material plasticity and offers a viable solution to enhance ductile-mode cutting of brittle materials. This study demonstrates the susceptibility of non-magnetic single-crystal calcium fluoride (CaF 2 ) to the magneto-plastic effect.

Abstract. New multifunctional nanoparticles (NPs) that can be used as contrast agents (CA) in different imaging techniques, such as photoluminescence (PL) …

Abstract. Optical absorption curves of CaF2 singly doped with Mn or Ce, and doubly doped with both Mn and Ce, show complex arrays of absorption bands after ...

Calcium fluoride is one of the favourite optical materials in the advanced optics applications owing to its superior optical transmission and mechanical properties. ... [Show full abstract ...

Abstract. Crystallization process in a fluidized bed reactor (FBR) has been regarded as an environmentally friendly technology for the removal and recovery of fluoride from industrial wastewater ...

Abstract. Bone is the main target of fluorosis, and it has been perfectly elaborated that a moderate dosage of calcium (Ca) can alleviate bone fluorosis. However, whether Ca can alleviate fluorosis through the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) signaling pathway has not yet been reported.

In sum, Ca 2+ -supplementation exerts antagonistic the toxic effects on fluoride and this inhibitory effect suggests the potential implications for Ca 2+ -supplementation on fluorosis. Calcium mitigates fluoride-induced kallikrein 4 inhibition via PERK/eIF2α/ATF4/CHOP endoplasmic reticulum stress pathway in ameloblast-lineage cells

Supplementation of Calcium and Fluoride-Free Water Mitigates Skeletal Fluorosis in Fluoride-Intoxicated Rats Biol Trace Elem Res. 2021 Jun;199(6):2225-2237. doi: 10.1007/s12011-020-02326-1. ... Abstract Fluorosis is a public health concern in 25 countries around the globe. The present study is about the mitigation of fluoride (F) …

Abstract Collagen fibrils present periodic structures, which provide space for intrafibrillar growth of oriented hydroxyapatite nanocrystals in bone and contribute to the good mechanical properties of bone. ... Mineralized tendons with organized calcium fluoride nanocrystals acquire mechanical properties (indentation elastic modulus ∼25.1 GPa ...

Abstract. Fluoride contamination in drinking water is a global issue. Frequent over-exposure to fluoride causes several health problems such as fluorosis, neurological, thyroid, osteoporosis, etc. The guideline values prescribed by the WHO and other nationals for fluoride in drinking water are reasonable but mostly relevant to fluorosis.

The novel calcium phosphate and fluoride nanocomposites could be rendered antibacterial with CHX to greatly reduce biofilm formation, acid production, CFU and metabolic activity. ... Abstract Objectives: Previous studies have developed calcium phosphate and fluoride releasing composites. Other studies have incorporated …

Abstract. Calcium fluoride is a dielectric material with a wide bandgap (∼12.1 eV) and a relatively high dielectric constant (∼6.8) that forms a van der Waals interface with two-dimensional ...

Here, a 3D thermal conductivity network has been successfully constructed inside the PI matrix by the combination of ionic liquids (IL) and calcium ... [Show full abstract] fluoride (CaF 2 ...

Abstract. The IR AR coating is of great importance in contemporary optics industry, thus in this theme we investigate deposition processes of anti-reflection coatings on calcium fluoride substrate using ion-assisted deposition, including single layer of ZnSYbF 3 and a multilayer coating of AR. These thin films are produced by thermal evaporation …

Abstract. Calcium fluoride, commonly called fluorspar or fluorite, is the principal fluoride‐containing mineral. Large deposits of flurospar are found in China, Mongolia, Mexico, Spain and South Africa. Underground mining procedures are used for deep fluorspar deposits and open‐pit mines are used for shallow deposits or where …

Graphical abstract. CaF 2 with different morphologies and hierarchical structure such as dendrites, ... The different temperature and heating time also have a certain influence on the morphology and crystallinity of calcium fluoride. Synthesis of Calcium Fluoride Nanoparticles From Waste Hexafluorisilicic Acid of Fertilizer Industry.

The removal mechanism is the chemical precipitation of calcium fluoride and hydroxyapatite. • The F and P removal percentages can exceed 99% and meet effluent standards. • The byproduct can treat wastewater even in acidic environments (pH 2-7). • Using byproducts to replace conventional agents can reduce CO 2 emissions in industry.

10.1016/j.cej.2022.139733. Bibcode: 2023ChEnJ.45339733Y. Keywords: Calcium fluoride; Fluoride recovery; Fluoride removal; Fluorine-containing wastewater; Column reactor. …