Infrared absorption study of Fe2O3–CaO–SiO2 glass ceramics

“…Other peaks in the spectra represent materialspecific peaks. For example, the presence of wollastonite (β-CaSiO 3 ) in both Polonite and natural wollastonite was indicated by peaks near 1056, 960, 902 and 680 cm -1 (Atalay et al, 2001). The observation that wollastonite was an important constituent of Polonite is in agreement with earlier studies employing chemical dissolution techniques and X-ray diffraction (Eveborn, 2003;Brogowski and Renman, 2004).…”

Section: Characterization Of Unused and Used Filter Materials With Atmentioning

confidence: 99%

Phosphate removal by mineral-based sorbents used in filters for small-scale wastewater treatment

et al. 2008

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The mineral-based sorbents Filtra P, Polonite ® , natural wollastonite and water-cooled blast furnace slag (WCBFS) were studied in terms of their PO 4 removal performance. Results from a long-term column experiment showed that both Filtra P and Polonite ® removed > 95 % of PO 4 from the applied synthetic solution, and that the used filter materials had accumulated several (1.9-19) g kg -1 P. Phosphorus was removed also by natural wollastonite and WCBFS, but these materials were less efficient. Batch experiments on the used materials showed that the solubility PO 4 was considerably larger than the one expected for crystalline Ca phosphates such as hydroxyapatite, and results from investigations with attenuated total reflectanceFourier-Transform infrared spectroscopy (ATR-FTIR) on the Filtra P material showed that the formed P phase was not crystalline. These evidence suggest that a soluble amorphous tricalcium phosphate (ATCP) was formed in the mineral-based sorbents; the apparent solubility constant on dissolution was estimated to log K s = -27.94 (±0.31) at 21 o C. However, since only up to 18 % of the accumulated PO 4 was readily dissolved in the experiments it cannot be excluded that part of the phosphorus had crystallized to slightly less soluble phases.In conclusion, Filtra P and Polonite are two promising mineral-based sorbents for phosphorus removal, and at least part of the accumulated phosphorus is present in a soluble form, readily available to plants.

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“…The broad bands in the range 300-500 nm are attributed to the intra configurationally 4f-4f transitions from the ground 7 F 0 level which corresponds to the excitation spectra. In case of smaller size nano particles, it is found that increase of defect distribution on the surface exhibit strong and broad absorption bands due to large surface to volume ratio [13,14] Mg 2 SiO 4 is calculated using Tauc relation [15]. The energy gap of the Eu 3+ (3 mol%) doped sample is found to be 5.84 eV.…”

Section: Resultsmentioning

confidence: 96%

Photoluminescence and thermoluminescence studies of Mg2SiO4:Eu3+ nano phosphor

Prashantha

Lakshminarasappa

Nagabhushana

2011

Journal of Alloys and Compounds

119

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Phosphor Photoluminescence Thermoluminescence Optical absorption a b s t r a c t Nanoparticles of Eu 3+ doped Mg 2 SiO 4 are prepared using low temperature solution combustion technique with metal nitrate as precursor and urea as fuel. The synthesized samples are calcined at 800• C for 3 h. The Powder X-ray diffraction (PXRD) patterns of the sample reveled orthorhombic structure with ␣-phase. The crystallite size using Scherer's formula is found to be in the range 50-60 nm. • C and 345• C besides a shoulder with peak at ∼240• C are observed. The trapping parameters-activation energy (E), order of kinetics (b) and frequency factor (s) are calculated using glow curve shape method and the results obtained are discussed.

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Infrared absorption study of Fe2O3–CaO–SiO2 glass ceramics

Cited by 79 publications

References 5 publications

RKKP bioactive glass-ceramic material through an aqueous sol-gel process

RKKP bioactive glass-ceramic material through an aqueous sol-gel process

Phosphate removal by mineral-based sorbents used in filters for small-scale wastewater treatment

Photoluminescence and thermoluminescence studies of Mg2SiO4:Eu3+ nano phosphor

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