Study and Characterization of Powders Nanocomposites Calcium Phosphate/Silica-Gel (SiO2n) Obtained from Attrition Milling: For Biomedical Applications

2008 ◽  
Vol 396-398 ◽  
pp. 615-618
Author(s):  
Rodrigo Brandão ◽  
Fernando Pupio ◽  
Nelson Heriberto A. Camargo ◽  
E. Gemelli

The bioceramics nanostructured have made important characteristics in biomedical applications, especially the calcium phosphate ceramics. The aim of this work is synthesis and characterization of calcium phosphate and nanocomposites powders, the method of dissolution of CaO in liquid medium, precipitation and formation of bone calcium phosphate matrix, and nanocomposites by adding the solution of phosphoric acid (H3PO4). The nanocomposites powders were synthesized using as strengthening silica gel nanometer (20nm) at concentrations of 1%, 2%, 3% and 5% by volume and subjected to heat treatment to 900°C for 2 hours, seeking obtained HA (Hydroxyapatite). Later the bone matrix of calcium phosphate and nanocomposites powders were subjected from process attrition milling for 2 hours, by way of comparison. The studies characterizations were conducted through the technique of X-ray diffraction, scanning electron microscopy (SEM) and dilatometric test.

2011 ◽  
Vol 233-235 ◽  
pp. 1790-1793 ◽  
Author(s):  
Wei Shen ◽  
Bao Jian Shen

Y zeolite was synthesized form silica gel microsphere by in- situ hydrothermal method, with appropriate amount of other constituents, such as sodium silicate, water, without adding any organic additives. The as-synthesized samples were characterized using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and N2 sorption. The results show that the synthesized sample not only has a composite structure with zeolite Y and silica gel, but also retains the shape of silica gel microsphere. The pore distribution of the composite materials indicated that the composite material contains two types of pore that are micropores and large pores.


2014 ◽  
Vol 70 (a1) ◽  
pp. C743-C743
Author(s):  
Tatiane Britos ◽  
Li Min ◽  
Lilia De Souza Li ◽  
Paula Haddad

This work reports the synthesis and characterization of superparamagnetic iron oxide nanoparticles (SPIONs), with great potential for biomedical applications. SPIONs were prepared through a decomposition of Fe(acac)3 in the presence of 1,2 hexadecanodiol (reducing agent), oleic acid and oleylamine (ligands) in a hot organic solvent. The mercaptosuccinic acid (MSA) and 2,3- dimercaptosuccinic acid (DMSA) were exchanged onto the nanocrystal surface making the particles stable in water. The thiolated nanoparticles (SH-NPs) were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM). The as-prepared sample presented an amorphous partially oxidized iron structure. The results showed that the SH-NPs have a mean diameter of 6 nm and display superparamagnetic behavior at room temperature. Preliminary tests of incorporation of these systems were evaluated in Hela cells and stem cells. The results showed that the thiolated nanoparticles have no toxic effects for both cell types with good incorporation after 6 hours of transfection. Magnetic resonance image (MRI) were also carried and showed that the MNPs increase the contrast in systems investigated. Acknowledgements: FAPESP (2011/10125-0), CNPq, CAPES, UNICAMP


2016 ◽  
Vol 869 ◽  
pp. 884-889
Author(s):  
Nadia Sueli Vieira Capanema ◽  
Alexandra A.P. Mansur ◽  
Herman Sander Mansur

The need for obtaining new materials to replace human body parts that were destroyed or damaged led scientists from different areas of research for developing new biomaterials. Thus, the aim of this work was the synthesis and characterization of niobium-modified apatite bioceramics. Calcium phosphates (CaP) were synthesized with niobium partially replacing calcium sites using aqueous precipitation route at room temperature. The bioceramics, with and without Nb incorporation, were characterized by scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) as prepared and after heat treatments The results indicated that Nb was incorporated in the apatite structure promoting morphological and structural changes in the ceramic properties.


2008 ◽  
Vol 396-398 ◽  
pp. 619-622 ◽  
Author(s):  
Nelson Heriberto A. Camargo ◽  
S. de Lima ◽  
Julio C.P. Souza ◽  
Juliana F. de Aguiar ◽  
E. Gemelli ◽  
...  

In the last decades many investigations have been oriented toward the development of nanostructured biomaterials such as calcium phosphate ceramics, particularly those composed of stoicheiometric hydroxyapatite (Ca10(PO4)6(OH)2) and a-and β- tricalcium phosphate (Ca3(PO4)2), which present chemical and crystallographic similarities with hard tissues (bones and teeth). Because of these characteristics, these materials can be used for reconstitution and regeneration of bone tissues. The odontological and biomedical applications are still limited due to their brittle behaviour. This study was focused in the synthesis and characterization of a bone matrix of calcium phosphate (β-TCP) and hydroxyapatite (HAP-101 e HAp-201). The results presented here are related to the morphological characterization of nanostructured powders from scanning electron microscopy viewpoint. X-ray diffraction was used to identifier the present phases in the powders and the infrared spectrometry (FTIR) was used to analyse OH bonds from hydroxyapatite and PO4 from calcium phosphates.


2018 ◽  
Vol 2 (1) ◽  
pp. 7
Author(s):  
S Chirino ◽  
Jaime Diaz ◽  
N Monteblanco ◽  
E Valderrama

The synthesis and characterization of Ti and TiN thin films of different thicknesses was carried out on a martensitic stainless steel AISI 410 substrate used for tool manufacturing. The mechanical parameters between the interacting surfaces such as thickness, adhesion and hardness were measured. By means of the scanning electron microscope (SEM) the superficial morphology of the Ti/TiN interface was observed, finding that the growth was of columnar grains and by means of EDAX the existence of titanium was verified.  Using X-ray diffraction (XRD) it was possible to observe the presence of residual stresses (~ -3.1 GPa) due to the different crystalline phases in the coating. Under X-ray photoemission spectroscopy (XPS) it was possible to observe the molecular chemical composition of the coating surface, being Ti-N, Ti-N-O and Ti-O the predominant ones.


Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 721 ◽  
Author(s):  
Jorge A. Ramírez-Gómez ◽  
Javier Illescas ◽  
María del Carmen Díaz-Nava ◽  
Claudia Muro-Urista ◽  
Sonia Martínez-Gallegos ◽  
...  

Atrazine (ATZ) is an herbicide which is applied to the soil, and its mechanism of action involves the inhibition of photosynthesis. One of its main functions is to control the appearance of weeds in crops, primarily in corn, sorghum, sugar cane, and wheat; however, it is very toxic for numerous species, including humans. Therefore, this work deals with the adsorption of ATZ from aqueous solutions using nanocomposite materials, synthesized with two different types of organo-modified clays. Those were obtained by the free radical polymerization of 4-vinylpyridine (4VP) and acrylamide (AAm) in different stoichiometric ratios, using tetrabutylphosphonium persulfate (TBPPS) as a radical initiator and N,N′-methylenebisacrylamide (BIS) as cross-linking agent. The structural, morphological, and textural characteristics of clays, copolymers, and nanocomposites were determined through different analytical and instrumental techniques, i.e., X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Adsorption kinetics experiments of ATZ were determined with the modified and synthesized materials, and the effect of the ratio between 4VP and AAm moieties on the removal capacities of the obtained nanocomposites was evaluated. Finally, from these sets of experiments, it was demonstrated that the synthesized nanocomposites with higher molar fractions of 4VP obtained the highest removal percentages of ATZ.


2020 ◽  
Vol 75 (6-7) ◽  
pp. 597-603
Author(s):  
Birgit Fuchs ◽  
Hubert Huppertz

AbstractThe non-centrosymmetric scandium borate ScB6O9(OH)3 was obtained through a high-pressure/high-temperature experiment at 6 GPa and 1473 K. Single-crystal X-ray diffraction revealed that the structure is isotypic to InB6O9(OH)3 containing borate triple layers separated by scandium layers. The compound crystallizes in the space group Fdd2 with the lattice parameters a = 38.935(4), b = 4.4136(4), and c = 7.6342(6) Å. Powder X-ray diffraction and vibrational spectroscopy were used to further characterize the compound and verify the proposed structure solution.


2012 ◽  
Vol 600 ◽  
pp. 174-177 ◽  
Author(s):  
Jian Fei Xia ◽  
Zong Hua Wang ◽  
Yan Zhi Xia ◽  
Fei Fei Zhang ◽  
Fu Qiang Zhu ◽  
...  

Zirconia-graphene composite (ZrO2-G) has been successfully synthesized via decomposition of ZrOCl2•6H2O in a water-isopropanol system with dispersed graphene oxide (GO) utilizing Na2S as a precursor could enable the occurrence of the deposition of Zr4+ and the deoxygenation of GO at the same time. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were used to characterize the samples. It was found that graphene were fully coated with ZrO2, and the ZrO2 existing in tetragonal phase, which resulted in the formation of two-dimensional composite.


2011 ◽  
Vol 197-198 ◽  
pp. 456-459
Author(s):  
Xian Ming Liu ◽  
Wen Liang Gao

Spinel-perovskite multiferroics of NiFe2O4/BiFeO3 nanoparticles were prepared by modified Pechini method. The structure and morphology of the composites were examined by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the composites consisted of spinel NiFe2O4 and perovskite BiFeO3 after annealed at 700°C for 2h, and the particle size ranges from 40 to 100nm. VSM and ME results indicated that the nanocomposites exhibited both tuning magnetic properties and a ME effect. The ME effect of the nanocomposites strongly depended on the magnetic bias and magnetic field frequency.


2012 ◽  
Vol 174-177 ◽  
pp. 508-511
Author(s):  
Lin Lin Yang ◽  
Yong Gang Wang ◽  
Yu Jiang Wang ◽  
Xiao Feng Wang

BiFeO3 polyhedrons had been successfully synthesized via a hydrothermal method. The as-prepared products were characterized by power X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The possible mechanisms for the formation of BiFeO3 polyhedrons were discussed. Though comparison experiments, it was found that the kind of precursor played a key role on the morphology control of BiFeO3 crystals.


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