Hydroxyapatite Scaffolds Produced by Hydrothermal Deposition of Monetite on Polyurethane Sponges Substrates

2011 ◽  
Vol 493-494 ◽  
pp. 820-825 ◽  
Author(s):  
Fernanda Danielle Mishima ◽  
Luis Henrique Leme Louro ◽  
Felipe Nobre Moura ◽  
Luciano Andrade Gobbo ◽  
Marcelo Henrique Prado da Silva

Hydroxyapatite scaffolds have been being produced by a wide range of processes. The optimun material to be used as bone graft has to be partially resorbable, with resorption rates similar to new bone formation ones. The samples must have porosity compatible with tissue ingrowth. Hydroxyapatite and tricalcium phosphate ceramics are good choices for designing such materials. In the present study, polymeric sponges were coated with hydroxyapatite and sintered. The method consists of coating polyurethane sponges substrates in an aqueous solution rich in phosphate (PO4)3-and calcium (Ca)2+ions. The solution is composed by 0.5M Ca(OH)2, 0.3M H3PO4and 1M CH3CHCO2HOH (lactic acid) at pH of 3.7. The sponges were immersed in a beaker with the solution and heated up to 80°C to precipitate monetite on the sponge. Continuous and adherent coatings were formed on the surface of sponges interconections. These coatings were characterised by X-ray diffractometry and the only identified phase was monetite. The substrates were converted to hydroxyapatite in an alkali solution.The total conversion from monetite to hydroxyapatite was confirmed by XRD analyses. The struts were heat treated in order to eliminate the organic sponge and sinter the scaffolds. After sintering, hydroxyapatite and tricalcium phosphate were identified on the struts. Optical microscopy revealed the morphology of the struts, while scanning electron microscopy (SEM) showed the precipitates morphology. The method showed to be efficient in the production of porous scaffolds.

2012 ◽  
Vol 476-478 ◽  
pp. 379-382 ◽  
Author(s):  
Delin Lai ◽  
Yong Chen ◽  
Da Xiang Yang ◽  
Wei Ling Guo ◽  
Yu Xi Yu

The alumina (Al2O3) nanofibers were fabricated by electrospinning a viscous mixture of aluminum isopropoxide solution in 10% aqueous solution of PVA followed by calcination at 500~1000 °C. Tools such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric and differential thermal analysis (TG-DTA) were employed to characterize the obtained nanofibers. When the nanofibers were heat treated at 1000 °C, the as-prepared nanofibers have a diameter in the range of 30 ~ 100 nm, and are composed of α-Al2O3.


Author(s):  
Ivan Saenko ◽  
O. Fabrichnaya

AbstractThermodynamic parameters were assessed for the MgO–FeOx system and combined with already available descriptions of ZrO2-FeOx and ZrO2-MgO systems to calculate preliminary phase diagrams for planning experimental investigations. Samples of selected compositions were heat treated at 1523, 1673 and 1873 K and characterized using x-ray and scanning electron microscopy combined with energy dispersive x-ray spectroscopy (SEM/EDX). Experiments indicated extension of cubic ZrO2 solid solution into the ternary system at 1873 K (75 mol.% ZrO2, 10 mol.% FeOx and 15 mol.% MgO) and limited solubility of 4 mol.% ZrO2 in spinel phase. Based on the obtained results thermodynamic parameters of C-ZrO2 and spinel phase were optimized.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Mingjie Ma ◽  
Guanyu Wang ◽  
Zhengpeng Yang ◽  
Shanxiu Huang ◽  
Weijie Guo ◽  
...  

Solid waste red mud was modified by HCl leaching. The structure property and composition of modified red mud were investigated by X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET). Under UV irradiation, methyl orange (MO) aqueous solution was photodegraded by modified red mud. The obtained results showed that the specific surface area of modified red mud was 317.14 m2/g, which was about 40 times higher than that of the normal red mud. After UV irradiation for 50 min, the removal percentage of MO reached 94.2%. The study provided a novel way for the application of red mud to the photocatalytic degradation of organic wastes.


2014 ◽  
Vol 915-916 ◽  
pp. 933-941 ◽  
Author(s):  
Zhong Jie Zhang ◽  
Chang Yu Lu ◽  
Wei Huang ◽  
Wei Sheng Guan ◽  
Yue Xin Peng

The effective remove to tetracycline still remains a big challenge for scientists. In this work, we used a new method for preparing functional magnetic CNTS with ferrite nanoparticles. A wide range of techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and magnetic measurements were applied to characterize the obtained Fe2O3/CNTs. Moreover, we have also studied the properties of adsorbent to tetracycline. In addition, we have found that the Fe2O3/CNTs are better reusable adsorbent than other traditional adsorbents by magnetic separation recycling method.


2011 ◽  
Vol 284-286 ◽  
pp. 781-785 ◽  
Author(s):  
Shi Cai Cui ◽  
Da Feng Zhang ◽  
Xi Peng Pu ◽  
Xian Hua Qian ◽  
Tian Tian Ge ◽  
...  

ZnO were rapidly synthesized using different zinc salts (Zn(NO3)2, Zn(CH3CO2)2, ZnCl2and ZnSO4) by an aqueous solution method at 90°C. The products were characterized by X-ray diffractometry and scanning electron microscopy. The results show that the anions have remarkable effects on the morphologies of ZnO. When Zn(NO3)2, Zn(CH3CO2)2or ZnCl2was used, ZnO was obtained with ellipsoidal, under-developed ellipsoidal and nano-particles morphologies, respectively. In the case of ZnSO4, layered basic zinc sulfate was obtained. The remarkable effects of anions on ZnO can be ascribed to the adsorption of the anions on the surface of ZnO, which hinders the further growth of ZnO nuclei. The effect of SO42-was further investigated by changing the mole ratio of SO42-to NO3-.


2015 ◽  
Vol 830-831 ◽  
pp. 143-146
Author(s):  
Jalpa Patel ◽  
Prashanth Huilgol ◽  
Nirav Jamnapura ◽  
K. Udaya Bhat

Coupons of 9Cr-1Mo steels of type SA 387 Grade 9 class 2 were hot dip aluminized using Al bath at a temperature of 700 °C for 30 seconds. The samples were further heat treated at 750 °C for durations of 1, 3 and 5 hours, respectively. The samples were characterized using X-ray diffractometry, scanning electron microscopy and energy dispersive spectroscopy. The investigation showed that as coated samples contain an aluminum top coat, a reaction layer and substrate material. Within the reaction layer, two distinct regions corresponding to Fe2Al5 and Fe4Al13 were identified. Chromium up to 2 at% was observed. After heat treatment Al coat was not existing. Two distinct layers, corresponding to a thick Fe2Al5 and a thin FeAl were observed at shorter heat treatment duration. Under longer heat treatment durations, multiple phases, namely, Fe2Al5, FeAl, Fe3Al and solid solution of Al in Fe were observed.


2014 ◽  
Vol 633-634 ◽  
pp. 341-344 ◽  
Author(s):  
Jia Yue Sun ◽  
Qiu Mei Di ◽  
Liu Han ◽  
Qi Guang Xu ◽  
Chen Liang Ma

Electron trapping materials SrSO4:Eu2+were prepared by hydrothermal method from fatty alcohol polyoxyethylene (3) ether (AEO-3) aqueous solution at 200 °C for 20 h. The phase structure, microstructure and optical properties were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and excitation-emission spectroscopy (PL-PLE), respectively.


2013 ◽  
Vol 203-204 ◽  
pp. 212-215 ◽  
Author(s):  
Bożena Łosiewicz ◽  
Grzegorz Dercz ◽  
Magdalena Szklarska ◽  
Wojciech Simka ◽  
Marta Łężniak ◽  
...  

The chitosan (CH) coatings on a Ti13Zr13Nb alloy substrate were obtained by electrophoretic deposition (EPD). The EPD yield was investigated under different deposition conditions. The microstructure of the CH coatings obtained by cataphoresis was studied by scanning electron microscopy and the chemical composition was examined using EDAX. The functional groups and formed phases were analyzed using Fourier transform infrared spectroscopy and X-ray diffraction, respectively. It was found that the CH coating thickness and porosity can be controlled by time and voltage used for the EPD process. It was ascertained that the studied EPD of the natural biopolymer, chitosan, in aqueous solution is applicable for the surface modification of the Ti13Zr13Nb implants to develop novel bioactive coatings.


2011 ◽  
Vol 393-395 ◽  
pp. 370-372
Author(s):  
Cun Jing Wang ◽  
Peng Yao ◽  
Gai Rong Chen

Catalytic decomposition of acetylene was carried out at 400 °C using iron supported on sodium chloride as catalyst and the product was heat-treated at 650 °C under an argon atmosphere for 2 h directly. The sample was examined by scanning electron microscopy, high resolution transmission electron microscopy and X-ray diffraction. The results show that nano onion-like fullerenes encapsulating Fe cores with diameters in the range 20-50 nm were obtained.


2015 ◽  
Vol 1109 ◽  
pp. 55-59 ◽  
Author(s):  
Nurhafizah Md Disa ◽  
Suriani Abu Bakar ◽  
S. Alfarisa ◽  
Azmi Mohamed ◽  
Illyas Md Isa ◽  
...  

In this study, electrochemical exfoliation method was adopted in the production of graphene oxide (GO). The electrolyte used was sodium dodecyl sulphate (SDS) aqueous solution at various concentrations from 0.001 to 1.0 M. The effect of SDS concentrations on the morphology of GO samples were characterized using field emission scanning electron microscopy (FESEM), energy dispersive X-ray, micro-Raman and UV-Vis spectroscopy. As evident by the FESEM analysis, the concentration of SDS does give effect to the GO obtained in this study. The lowest GO production is given by the lowest concentration of SDS used which is 0.001 M. However, in term of ID/IGratio, the sample prepared at 0.001 M has the lowest value (0.33) as compared to the sample prepared with highest SDS concentration of 1.0 M (ID/IG~1.12). Meanwhile, the presence of absorbance peaks in the range of 224-237 nm from UV-Vis spectra analysis were seen for the whole samples and this indicate the formation of GO.


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