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Chuanxian Ding - One of the best experts on this subject based on the ideXlab platform.

  • in vitro cytocompatibility of plasma sprayed Dicalcium Silicate zirconia composite coating
    Materials Science Forum, 2009
    Co-Authors: Xuebin Zheng, Chuanxian Ding, Yi Zeng
    Abstract:

    The in vitro attachment, spread, and proliferation behavior of osteoblast cells on the plasma-sprayed composite coating with 70wt% zirconia and 30wt% Dicalcium Silicate were studied. The composite coating shows good cytocompatibility. The human osteoblast cells attached, spread and proliferate well on the surface. The cytocompatibility of the coating was attributed to the incongruent dissolution of Dicalcium Silicate and the large amount of Si-OH functional groups produced on the surface. The released calcium and silicon ions are also positive to the proliferation of cells. All our results show that the composite coating possesses good cytocompatibility.

  • In Vitro Cytocompatibility of Plasma-Sprayed Dicalcium Silicate/Zirconia Composite Coating
    Materials Science Forum, 2009
    Co-Authors: Xuebin Zheng, Chuanxian Ding, Yi Zeng
    Abstract:

    The in vitro attachment, spread, and proliferation behavior of osteoblast cells on the plasma-sprayed composite coating with 70wt% zirconia and 30wt% Dicalcium Silicate were studied. The composite coating shows good cytocompatibility. The human osteoblast cells attached, spread and proliferate well on the surface. The cytocompatibility of the coating was attributed to the incongruent dissolution of Dicalcium Silicate and the large amount of Si-OH functional groups produced on the surface. The released calcium and silicon ions are also positive to the proliferation of cells. All our results show that the composite coating possesses good cytocompatibility.

  • Durability of Titanium/Dicalcium Silicate Composite Coatings in Simulated Body Fluid
    Journal of Thermal Spray Technology, 2007
    Co-Authors: Xuebin Zheng, Chuanxian Ding
    Abstract:

    Titanium/Dicalcium Silicate composite coatings with different ratios (weight ratios as Ca2SiO4: Ti = 3:7, 5:5, 7:3) were prepared by plasma spraying. Effects of titanium addition on coating properties, such as bonding strength, flexural modulus, and dissolution in simulated physiological environment, were studied. Results showed that the bonding strength between coating and Ti-6Al-4V substrate increased with increase of titanium content in the composite coatings. It was explained by the narrowed dissimilarity of thermal expansion coefficients between the coatings and substrates. Degradation of mechanical properties after immersion in simulated body fluid was also studied. The dissolution of Dicalcium Silicate in the composite coatings resulted in the decrease of flexural strength and flexural modulus of the coatings in the simulated physiological environment. The higher titanium content in the composite coatings, the stabler are the composite coatings in the physiological environment.

  • improved stability of plasma sprayed Dicalcium Silicate zirconia composite coating
    Thin Solid Films, 2006
    Co-Authors: Xuebin Zheng, Chuanxian Ding
    Abstract:

    Dicalcium Silicate/zirconia composite coatings were produced on Ti–6Al–4V substrates using atmospheric plasma spraying. Different weight ratios of zirconia (50 wt.%, 70 wt.%, 90 wt.%) were mechanically blended with Dicalcium Silicate (C2S) powders as feedstocks. The composite coatings were immersed in a simulated body fluid (SBF) and a Tris–HCl solution for the in vitro appraisement of stability and long-term performance in a biological environment. The ion concentration changes of Ca, Si, and P in SBF and Tris–HCl solution were monitored using inductively-coupled plasma atomic emission spectroscopy (ICP–AES). Compared to the pure C2S coating, our results show that the dissolution rate of the composite coatings is effectively reduced and the stability is improved by the addition of zirconia. The high content of zirconia in the coatings ensures the long-term performance in biological environment, while dissolution of C2S in the coatings results in a higher Ca ion concentration in SBF and rapid precipitation of bone-like apatite on the composite coating surfaces indicating good bioconductivity of the coatings.

  • Improved stability of plasma-sprayed Dicalcium Silicate/zirconia composite coating
    Thin Solid Films, 2006
    Co-Authors: Xuebin Zheng, Chuanxian Ding
    Abstract:

    Dicalcium Silicate/zirconia composite coatings were produced on Ti–6Al–4V substrates using atmospheric plasma spraying. Different weight ratios of zirconia (50 wt.%, 70 wt.%, 90 wt.%) were mechanically blended with Dicalcium Silicate (C2S) powders as feedstocks. The composite coatings were immersed in a simulated body fluid (SBF) and a Tris–HCl solution for the in vitro appraisement of stability and long-term performance in a biological environment. The ion concentration changes of Ca, Si, and P in SBF and Tris–HCl solution were monitored using inductively-coupled plasma atomic emission spectroscopy (ICP–AES). Compared to the pure C2S coating, our results show that the dissolution rate of the composite coatings is effectively reduced and the stability is improved by the addition of zirconia. The high content of zirconia in the coatings ensures the long-term performance in biological environment, while dissolution of C2S in the coatings results in a higher Ca ion concentration in SBF and rapid precipitation of bone-like apatite on the composite coating surfaces indicating good bioconductivity of the coatings.

Xuebin Zheng - One of the best experts on this subject based on the ideXlab platform.

  • in vitro cytocompatibility of plasma sprayed Dicalcium Silicate zirconia composite coatings
    Ceramics International, 2013
    Co-Authors: Xuebin Zheng, Li Ping Huang, Chunmei Ding
    Abstract:

    Abstract Dicalcium Silicate/zirconia composite coatings composed of 70 wt% zirconia and 30 wt% Dicalcium Silicate were prepared by plasma spraying. Human osteoblasts were used for evaluation of the cytocompatibility of the composite coatings with Ti and hydroxyapatite (HA) coatings used as controls. The cells on the composite coatings possessed abundant extensions, and the cell number was also the highest among these coatings. During the 7 days culture, cell density on the composite coatings maintained higher than that on the Ti coatings, but similar to that on the HA coatings. To evaluate the bioactivity, the composite coatings were immersed in simulated body fluids and cell culture media. Ca–P minerals were deposited on the coating surface after immersion in the cell culture media for 1 day, while only scattered particles were found after soaking in simulated body fluids for 2 days. The enhanced Ca–P mineral formation rate of the composite coatings was explained by the Si–OH functional groups and the adsorbed proteins on the coating surface.

  • In vitro cytocompatibility of plasma-sprayed Dicalcium Silicate/zirconia composite coatings
    Ceramics International, 2013
    Co-Authors: Xuebin Zheng, Li Ping Huang, Chunmei Ding
    Abstract:

    Abstract Dicalcium Silicate/zirconia composite coatings composed of 70 wt% zirconia and 30 wt% Dicalcium Silicate were prepared by plasma spraying. Human osteoblasts were used for evaluation of the cytocompatibility of the composite coatings with Ti and hydroxyapatite (HA) coatings used as controls. The cells on the composite coatings possessed abundant extensions, and the cell number was also the highest among these coatings. During the 7 days culture, cell density on the composite coatings maintained higher than that on the Ti coatings, but similar to that on the HA coatings. To evaluate the bioactivity, the composite coatings were immersed in simulated body fluids and cell culture media. Ca–P minerals were deposited on the coating surface after immersion in the cell culture media for 1 day, while only scattered particles were found after soaking in simulated body fluids for 2 days. The enhanced Ca–P mineral formation rate of the composite coatings was explained by the Si–OH functional groups and the adsorbed proteins on the coating surface.

  • in vitro cytocompatibility of plasma sprayed Dicalcium Silicate zirconia composite coating
    Materials Science Forum, 2009
    Co-Authors: Xuebin Zheng, Chuanxian Ding, Yi Zeng
    Abstract:

    The in vitro attachment, spread, and proliferation behavior of osteoblast cells on the plasma-sprayed composite coating with 70wt% zirconia and 30wt% Dicalcium Silicate were studied. The composite coating shows good cytocompatibility. The human osteoblast cells attached, spread and proliferate well on the surface. The cytocompatibility of the coating was attributed to the incongruent dissolution of Dicalcium Silicate and the large amount of Si-OH functional groups produced on the surface. The released calcium and silicon ions are also positive to the proliferation of cells. All our results show that the composite coating possesses good cytocompatibility.

  • In Vitro Cytocompatibility of Plasma-Sprayed Dicalcium Silicate/Zirconia Composite Coating
    Materials Science Forum, 2009
    Co-Authors: Xuebin Zheng, Chuanxian Ding, Yi Zeng
    Abstract:

    The in vitro attachment, spread, and proliferation behavior of osteoblast cells on the plasma-sprayed composite coating with 70wt% zirconia and 30wt% Dicalcium Silicate were studied. The composite coating shows good cytocompatibility. The human osteoblast cells attached, spread and proliferate well on the surface. The cytocompatibility of the coating was attributed to the incongruent dissolution of Dicalcium Silicate and the large amount of Si-OH functional groups produced on the surface. The released calcium and silicon ions are also positive to the proliferation of cells. All our results show that the composite coating possesses good cytocompatibility.

  • Durability of Titanium/Dicalcium Silicate Composite Coatings in Simulated Body Fluid
    Journal of Thermal Spray Technology, 2007
    Co-Authors: Xuebin Zheng, Chuanxian Ding
    Abstract:

    Titanium/Dicalcium Silicate composite coatings with different ratios (weight ratios as Ca2SiO4: Ti = 3:7, 5:5, 7:3) were prepared by plasma spraying. Effects of titanium addition on coating properties, such as bonding strength, flexural modulus, and dissolution in simulated physiological environment, were studied. Results showed that the bonding strength between coating and Ti-6Al-4V substrate increased with increase of titanium content in the composite coatings. It was explained by the narrowed dissimilarity of thermal expansion coefficients between the coatings and substrates. Degradation of mechanical properties after immersion in simulated body fluid was also studied. The dissolution of Dicalcium Silicate in the composite coatings resulted in the decrease of flexural strength and flexural modulus of the coatings in the simulated physiological environment. The higher titanium content in the composite coatings, the stabler are the composite coatings in the physiological environment.

Jiang Chang - One of the best experts on this subject based on the ideXlab platform.

  • setting properties and biocompatibility of Dicalcium Silicate with varying additions of tricalcium aluminate
    Journal of Biomaterials Applications, 2012
    Co-Authors: Jiang Chang
    Abstract:

    This study sought to prepare biphasic mixtures by adding tricalcium aluminate (Ca3Al2O6) into Dicalcium Silicate (Ca2SiO4) and to evaluate the effect of Ca3Al2O6 on setting properties and biocompatibility of the Ca2SiO4/Ca3Al2O6 mixtures as compared to pure Ca2SiO4. The results indicated that the addition of Ca3Al2O6 into Ca2SiO4 reduced the setting time and improved the compressive strength. Furthermore, Ca2SiO4/Ca3Al2O6 mixtures were bioactive and biocompatible, and had a stimulatory effect on the L929 cell growth when the content of Ca3Al2O6 was below 10%. Therefore, the mixtures with 10% Ca3Al2O6 produced the best compromise between setting and in vitro biological properties.

  • low temperature synthesis of nanocrystalline β Dicalcium Silicate with high specific surface area
    Journal of Nanoparticle Research, 2007
    Co-Authors: Xianghui Huang, Jiang Chang
    Abstract:

    β-Dicalcium Silicate (β-Ca2SiO4) was synthesized for the first time by a simple solution combustion method using citric acid as fuel. The influence of calcination temperature on the average crystallite size, specific surface area and morphology of the powders were investigated by X-ray diffraction technique (XRD), scanning electron microscopy (SEM) and N2 adsorption measurements (BET). The results showed that the increase of calcination temperature from 650°C to 1100°C resulted in larger crystallite size and lower specific surface area of β-Ca2SiO4. The highest specific surface area could reach as high as 26.7 m2/g when the as-burnt powders were calcined at 650°C.

  • fabrication and characterization of polysulfone Dicalcium Silicate composite films
    Journal of Biomaterials Applications, 2006
    Co-Authors: Wei Cheng, Jiang Chang
    Abstract:

    Polysulfone (PSU) composite films filled with β-Dicalcium Silicate (-Ca2SiO4) particles are prepared by the solvent casting-evaporation method. The surface morphologies and mechanical properties of the films are determined. The bioactivity of the composite films is evaluated by soaking them in simulated body fluid (SBF) and the results show that the composites are bioactive as they induce the formation of hydroxyapatite (HAp) on the surface of the composite films. The measurement of the water contact angles suggests that the incorporation of -Ca2SiO4 particles into PSU matrix can improve the hydrophilicity of the composite. PSU composite films filled with modified -Dicalcium Silicate (-mCa2SiO4) particles are also prepared after -Ca2SiO4 particles are treated with dodecyl alcohol through surface esterification reactions. The infrared spectra of the -mCa2SiO4 particles before and after aging in water indicate that the surface modification is reversible. The scanning electron microscope (SEM) images (microg...

  • synthesis and in vitro bioactivity of Dicalcium Silicate powders
    Journal of The European Ceramic Society, 2004
    Co-Authors: Jiang Chang
    Abstract:

    Abstract In the present investigation, β-Dicalcium Silicate (β-Ca 2 SiO 4 ) and γ-Dicalcium Silicate (γ-Ca 2 SiO 4 ) powders were synthesized by sol-gel process and hydrothermal synthesis, respectively. The in vitro bioactivity of both β-, and γ-Ca 2 SiO 4 was investigated by soaking the powders in simulated body fluid (SBF) for various time periods to analyze the nucleation and growth of hydroxyapatite (HAp) on the surface of the powders. After soaked in SBF for 6 h, HAp appeared on the surface of β-, and γ-Ca 2 SiO 4 particles, and uniform lathlike aggregates with typical morphology of HAp crystals formed after 5 days. The β-Ca 2 SiO 4 showed strong hydration when soaked in SBF and the hydration was favorable for formation of carbonate-containing hydroxyapatite on the surface of the materials. The γ-Ca 2 SiO 4 was not hydrated in SBF solution and showed a slower formation of carbonate-containing hydroxyapatite on the surface when compared with β-Ca 2 SiO 4 . In addition, the Si concentration in the SBF increased quickly up to 5 days and remained invariable with increased soaking time. The results obtained indicate that hydroxyapatite nuclei can form and grow on the β-, and γ-Ca 2 SiO 4 particles, and these two Dicalcium Silicates are potential candidates as biomaterials for hard tissue repair.

A Diouri - One of the best experts on this subject based on the ideXlab platform.

  • potential formation of hydroxyapatite in total blood and Dicalcium Silicate elaborated from shell and glass powders
    Materials Letters, 2016
    Co-Authors: A Bouregba, A Diouri
    Abstract:

    Abstract This paper demonstrates the feasibility of using mussel shells and soda-lime glass powders for preparing Dicalcium Silicate (Ca 2 SiO 4 , C 2 S), by solid state reaction, then to synthesis hydroxyapatite, (Ca 10 (PO 4 ) 6 (OH) 2 , HAp), by soaking the powder of Dicalcium Silicate in a biological medium for a variety of time periods from 2 h to 5 days. The specimens are characterized by X-ray diffraction (XRD) and Fourier transformed infrared spectroscopy (FT-IR). The results shows that solid state reaction method allows the synthesis of Dicalcium Silicate powder by heating mixture of mussel shells and the soda-lime glass powders at 1050 °C. The results also shows that the hydroxyapatite is formed after soaking Dicalcium Silicate powder in total human blood for 20 h and growth up to 5 days.

  • hydration of iron phosphorus doped Dicalcium Silicate phase
    Materials Chemistry and Physics, 2005
    Co-Authors: My Y Benarchid, A Diouri, A Boukhari, J Aride, Imad Elkhadiri
    Abstract:

    Abstract The effect of iron and phosphorus addition on the formation and the hydration of Dicalcium Silicate Ca2SiO4 has been investigated. Synthesized solid solutions were analysed by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. The hydraulic reactivity of synthesized powders was followed by means of isothermal conduction microcalorimetry. The results showed that the β, α′ and α-Ca2SiO4 formation with Fe and P additions less than 9.50 wt.% Fe2O3 and 8.45 wt.% P2O5. The solid solution of α′ polymorph exhibited an early hydration higher than that in β modification.

  • Hydration of iron–phosphorus doped Dicalcium Silicate phase
    Materials Chemistry and Physics, 2005
    Co-Authors: My Y Benarchid, A Diouri, A Boukhari, J Aride, Imad Elkhadiri
    Abstract:

    Abstract The effect of iron and phosphorus addition on the formation and the hydration of Dicalcium Silicate Ca2SiO4 has been investigated. Synthesized solid solutions were analysed by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. The hydraulic reactivity of synthesized powders was followed by means of isothermal conduction microcalorimetry. The results showed that the β, α′ and α-Ca2SiO4 formation with Fe and P additions less than 9.50 wt.% Fe2O3 and 8.45 wt.% P2O5. The solid solution of α′ polymorph exhibited an early hydration higher than that in β modification.

  • Synthesis and thermal study of chromium-phosphorus doped Dicalcium Silicate
    World cement, 1999
    Co-Authors: Z. Qotaibi, A Diouri, A Boukhari, J Aride, J. Rogez, R. Castanet
    Abstract:

    The effect of chromium and phosphorus oxides on the formation of Dicalcium Silicate has been investigated. Synthesised powders were analysed by X-ray diffraction and scanning electron microscopy. Free lime has been determined by chemical analysis. Temperatures of decarbonation and enthalpy evolution during the firing have been studied. DTA technique shows the decrease of decarbonation temperature with addition of chromium and phosphorus oxides. During the formation of belite, the consumed energy, measured using isothermal calorimetry, decreases with the addition of Cr 2 O 3 and P 2 O 5 compounds

Hideo Toraya - One of the best experts on this subject based on the ideXlab platform.

  • crystallographic data of a new phase of Dicalcium Silicate
    Journal of the American Ceramic Society, 2005
    Co-Authors: Makoto Miyazaki, Kaori Sasaki, Hideki Ishida, Satoru Yamazaki, Hideo Toraya
    Abstract:

    Unit-cell parameters and the space group of a new phase of Dicalcium Silicate (Ca2SiO4) were determined by using powder X-ray diffractometry and selected-area electron diffraction techniques. This phase could be synthesized via the dissociation of hydrothermally synthesized alpha-Ca2(SiO4H)OH at temperatures of ∼500°-920°C. Crystallographic data for the sample synthesized at 600°C were as follows: Ca2SiO4, monoclinic; P21/c space group; lattice parameters of a= 0.82147(9) nm, b= 0.9808(1) nm, c= 0.9741(1) nm, and β= 94.642(7)°; cell volume (V) of 0.7857(1) nm3; Z= 8 (where Z is the number of chemical formula units in a unit cell); and a density of 2.91 g/cm3. The crystallographic data for samples synthesized at 800°C had slightly different unit-cell parameters of a= 0.82124(6) nm, b= 0.97348(7) nm, c= 0.97935(7) nm, β= 94.831(5)°, and V= 0.7849(1) nm3. Structural relationships of the new phase with the other Dicalcium Silicates are discussed.

  • simulated annealing structure solution of a new phase of Dicalcium Silicate ca2sio4 and the mechanism of structural changes from α Dicalcium Silicate hydrate to αl Dicalcium Silicate via the new phase
    Acta Crystallographica Section B-structural Science, 2002
    Co-Authors: Hideo Toraya, S Yamazaki
    Abstract:

    A new phase of Dicalcium Silicate (Ca2SiO4) was formed by heating α-Dicalcium Silicate hydrate [α-Ca2(SiO4H)OH = α-C2SH] at temperatures of ∼663–763 K, and it was transformed into \alpha _{\rm L} ^\prime-Ca2SiO4 (= \alpha _{\rm L} ^\prime-C2S) above ∼1193 K. The crystal structure of the new phase (hereafter called x-C2S) has been determined by simulated annealing and refined by the Rietveld method using synchrotron radiation powder diffraction data. The structure consists of isolated SiO4 tetrahedra and a three-dimensional CaOn polyhedral network, forming a new structural type of Dicalcium Silicate. A structural change from α-C2SH to x-C2S is compelled by large displacements of SiO4 tetrahedra, accompanied by dehydration, in the direction perpendicular to the two-dimensional Ca(O,OH)n polyhedral network in α-C2SH. With increasing temperature, sizes of CaOn polyhedra in x-C2S become too large to confine Ca atoms at the sixfold to eightfold coordination sites. Then the structure of x-C2S is transformed into \alpha _{\rm L} ^\prime-C2S, having eightfold to tenfold coordination sites for the Ca atoms.

  • Simulated annealing structure solution of a new phase of Dicalcium Silicate Ca(2)SiO(4) and the mechanism of structural changes from alpha-Dicalcium Silicate hydrate to alpha(L)'-Dicalcium Silicate via the new phase.
    Acta crystallographica. Section B Structural science, 2002
    Co-Authors: Hideo Toraya, S Yamazaki
    Abstract:

    A new phase of Dicalcium Silicate (Ca(2)SiO(4)) was formed by heating alpha-Dicalcium Silicate hydrate [alpha-Ca(2)(SiO(4)H)OH = alpha-C(2)SH] at temperatures of approximately 663-763 K, and it was transformed into alpha(L)'-Ca(2)SiO(4) (= alpha(L)'-C(2)S) above approximately 1193 K. The crystal structure of the new phase (hereafter called x-C(2)S) has been determined by simulated annealing and refined by the Rietveld method using synchrotron radiation powder diffraction data. The structure consists of isolated SiO(4) tetrahedra and a three-dimensional CaO(n) polyhedral network, forming a new structural type of Dicalcium Silicate. A structural change from alpha-C(2)SH to x-C(2)S is compelled by large displacements of SiO(4) tetrahedra, accompanied by dehydration, in the direction perpendicular to the two-dimensional Ca(O,OH)(n) polyhedral network in alpha-C(2)SH. With increasing temperature, sizes of CaO(n) polyhedra in x-C(2)S become too large to confine Ca atoms at the sixfold to eightfold coordination sites. Then the structure of x-C(2)S is transformed into alpha(L)'-C(2)S, having eightfold to tenfold coordination sites for the Ca atoms.

  • X-ray powder data for a new phase of Dicalcium Silicate, x-Ca 2 SiO 4
    Powder Diffraction, 2001
    Co-Authors: Satoru Yamazaki, Hideo Toraya
    Abstract:

    X-ray powder diffraction data for a new phase of Dicalcium Silicate, x-Ca2SiO4, are reported. The sample was prepared by the dehydration of hydrothermally synthesized α-type Dicalcium Silicate hydrate, Ca2(SiO4H)OH, at a temperature of 800 °C. Crystallographic data were Ca2SiO4, monoclinic, P21/c (No. 14), a=8.2127(5), b=9.7930(4), c=9.7954(5) Å, β=94.848(5)°, V=785.00(7) Å3, Z=8, and Dx=2.91 g·cm−3.