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Impact of Dental Caries on Survival of Polymeric Restorations
Published in Mary Anne S. Melo, Designing Bioactive Polymeric Materials for Restorative Dentistry, 2020
Maximiliano Sérgio Cenci, Tamires Timm Maske, Françoise Hélène van de Sande
Resin composites have been developed as an attempt to promote F ion-release and therefore help in the carious lesion control. Different approaches to impart fluoride ion-releasing capability to composite materials have been reported. The initial reports address the incorporation of either water-soluble salts (NaF or SnF2), matrix-bound fluoride, or fluoride-releasing filler systems (Arends et al., 1995). When soluble salts and matrix-bound fluoride are incorporated in the composite material, an easy washout of fluoride ions is related to the weakness of material proprieties. However, the incorporation of fluoride-releasing filler as strontium fluoride (SrF2) or Ytterbium trifluoride (YbF3) has shown good mechanical and physical proprieties (Wiegand et al., 2007).
A computational study to explore the effects of copper doping concentration on phase stability, electronic band structure and optical properties of CsSrF3 fluro-perovskite
Published in Molecular Physics, 2021
Muhammad Rizwan, Waqar Azam, S. S. A. Gillani, I. Zeba, M. Shakil, S. S. Ali, Riaz Ahmad
Caesium Strontium Fluoride belongs to perovskite family with chemical formula CsSrF3 where strontium, caesium and fluorine have ionic and covalent combination with each other. It is theoretically reported to have a wide direct band gap of 6.34 eV [45]. The reported lattice constants are 4.75 [2], 4.83 [45] and 4.64 Å [45]. This compound has a highly ionic nature. At the room temperature, the perovskite structure with Centro symmetric behaviour is para-electric as well as conductive. CsSrF3 perovskite material is an optical active material. It can be used for optical-electronic and photonic devices effectively. Due to its wide bandgap and low refractive-index this fluoride-type material can be used for protective coating as well as for anti-reflection coating in solar devices [45].
Fabrication of <001>-oriented apatite ceramics using a non-topochemical reactive α-tristrontium phosphate template
Published in Journal of Asian Ceramic Societies, 2020
Shuhei Yoshida, Akihiro Ishida, Akitoshi Suzumura, Yoshihiro Kishida, Toshihiko Tani, Mamoru Aizawa
First, plate-like α-TSP particles (17.5 g) and strontium fluoride (SrF2, Sigma-Aldrich, St. Louis, USA) particles (1.4741 g) were mixed in an agate mortar in a stoichiometric ratio. The solvent was then prepared by mixing ethanol and toluene. Slurries for tape casting were prepared by mixing the starting materials, solvent, binder (polyvinyl butyl), and plasticizer (dibutyl phthalate). Green sheets were produced by tape casting using a doctor’s blade. The sheets were cut, laminated, and pressed at 80°C and 20 kgf•cm−2 to form green compacts. These were cut into smaller pieces (10 × 10 mm) that are referred to hereafter as “stacked specimens”. The stacked specimens were heated in air at 500°C for 1 h in an electric furnace (TFF300 No. F611, Tokyo Technological Labo Co., Ltd., Japan) to remove organic ingredients, heated in air at 1000°C for 10 h, and, final sintered at 1500°C for 2 h in an electric furnace (SC-3035F-SP, Motoyama Corporation, Japan).
Fluorapatite as immobilization matrix for nuclear waste
Published in Radiation Effects and Defects in Solids, 2018
Elena Macerata, Elisabetta Pizzi, Annalisa Ossola, Marco Giola, Mario Mariani
In order to improve the synthetic procedure for the preparation of Sr-substituted fluorapatites by solid-state reaction, a new synthetic route was proposed. The new procedure permits the preparation of fluorapatites with a Sr content up to 100% by means of a two-step method: The preparation of tristrontium phosphate Sr3(PO4)2 (SrPh), starting from different Sr-containing precursors;The synthesis of Sr-substituted fluorapatites Ca10-xSrx(PO4)6F2 (SrxFAp), starting from a mixture of strontium phosphate, calcium phosphate, strontium fluoride or calcium fluoride.