http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Preparation of GdCaAl3O7 : Eu nanoparticles by a combustion method and their characterization
Sousan Rasouli,Amir M. Arabi,Saeideh Gorji Kandi 한양대학교 세라믹연구소 2012 Journal of Ceramic Processing Research Vol.13 No.1
GdCaAl3O7 : Eu nanoparticles were synthesized using a metal nitrate solution with glycine as fuel. X-ray diffraction (XRD), a scanning electron microscope (SEM), a transmission electron microscope (TEM) and a photoluminescence spectrophotometer (PL) were used to characterize the products obtained. XRD patterns revealed that a pure GdCaAl3O7 : Eu phase was formed by combustion of the metal nitrate solution in the presence of glycine at pH = 4. The appearance of spongy agglomerates indicates large amounts of exhaust gases and intense ignition of the powder obtained. SEM and TEM images showed that the agglomerates consisted of nanoparticles and 5-10 nm nanopores. An investigation of the chromaticity of the synthesized naophosphors showed that all samples synthesized at pH = 1 (after calcination), pH = 3 and pH = 4 have a red emission under 245 nm UV lighting. Furthermore, the synthesized sample at pH = 1 (after calcination) and the sample synthesized at pH = 4have almost the same CIE chromaticity xy values.
Sousan Rasouli 한양대학교 세라믹연구소 2011 Journal of Ceramic Processing Research Vol.12 No.6
In the present study, cobalt-doped ZnO nano pigments were synthesized by a solution gel combustion method using glycine fuel. A chamber furnace and microwave irradiation were used as heating sources. Products were characterized by X-ray diffraction, scanning-transmission electron microscopy and diffuse reflectance. The anticorrosive properties of the pigments obtained were investigated by electrochemical impedance spectroscopy. The results have shown that using glycine as the fuel pure ZnO phase was obtained directly by the two heating sources. Electron microscopy demonstrated quasi-spherical particles with a crystallite size of 49 nm for furnace-assisted and rod-like particles of 63 nm for the microwave-assisted procedure were obtained. The corrosion performance of the coating in 3% w/V NaCl solution was evaluated by electrochemical impedance spectroscopy (EIS) and polarization measurements. According to the measurements of EIS and electrochemical polarization,the coatings with a furnace-assisted pigment showed a higher corrosion resistance.
Sousan Rasouli,Fatemeh Oshani,Seyed Masoud Hashemi 한양대학교 세라믹연구소 2012 Journal of Ceramic Processing Research Vol.13 No.2
TiO2 nanosheets were synthesized by a combustion method using a metal nitrate solution combustion and urea fuel. Microwave irradiation was used as the heating source. X-ray diffraction, scanning and transmission electron microscopy as well as specific surface area analysis and Fourier transform infrared spectroscopy were performed to characterize the samples obtained. X-ray diffraction patterns revealed that the ratio of rutile/anatase phases varied from 25/75 to 69/31 as the fuel-tooxidizer (i.e. urea/titanyl nitrate) ratio changed from lean to rich. The crystallite size of the as-synthesized samples calculated by the Scherrer formula was 6.5-63 nm. From scanning and transmission microscopy images flaky particles with loose packed agglomerates in the form of nanosheets were detected. Due to the smaller crystallite size and higher content of the anatase phase, the fuel lean sample seemed to be a better candidate for photo-catalytic functions. TiO2 nanosheets were synthesized by a combustion method using a metal nitrate solution combustion and urea fuel. Microwave irradiation was used as the heating source. X-ray diffraction, scanning and transmission electron microscopy as well as specific surface area analysis and Fourier transform infrared spectroscopy were performed to characterize the samples obtained. X-ray diffraction patterns revealed that the ratio of rutile/anatase phases varied from 25/75 to 69/31 as the fuel-tooxidizer (i.e. urea/titanyl nitrate) ratio changed from lean to rich. The crystallite size of the as-synthesized samples calculated by the Scherrer formula was 6.5-63 nm. From scanning and transmission microscopy images flaky particles with loose packed agglomerates in the form of nanosheets were detected. Due to the smaller crystallite size and higher content of the anatase phase, the fuel lean sample seemed to be a better candidate for photo-catalytic functions.
Sousan Rasouli 한양대학교 세라믹연구소 2014 Journal of Ceramic Processing Research Vol.15 No.4
Field flow fractionation is a family of separation techniques applicable to characterize various particulate materials of different nature. In this paper, formation of porous graphite during milling has been investigated by gravitational field flow fractionation. The results from gravitational field flow fractionation were compared to those from Brunauer-Emmett-Teller. The both techniques have shown that particles fracturing and formation of porous graphite was occurred until 50 h milling. Further milling resulted in formation of agglomerated species. There was a good accordance between the results obtained from gravitational field flow fractionation, Brunauer-Emmett-Teller and scanning electron microscopy. Moreover, fractions of porous and non-porous species could be separated by gravitational field flow fractionation technique. Results demonstrated that gravitational field flow fractionation is a simple method with satisfactory results to investigate the evolution of graphite powder during milling process.
Microwave-assisted gel combustion synthesis of ZnO-Co nano-pigments
Sousan Rasouli,Mahdiar Valefi,Shirin Jebeli Moeen,Amir Masoud Arabi 한양대학교 세라믹연구소 2011 Journal of Ceramic Processing Research Vol.12 No.4
ZnO-Co ceramic pigments have been prepared by microwave-assisted gel combustion of zinc-nitrate-nitrate cobalt-citric acid precursors calcined at 700 to 1000 oC. The Combustion process has been investigated using thermal analysis and Fourier transformation infrared spectroscopy. X-ray diffraction, diffuse reflectance and scanning-transition electron microscopy was used to characterize the pigments. Results were compared with a solid state reaction. It was demonstrated that powders synthesis by combustion caused 200 oC reduction in the calcination temperature compared with the solid state reaction. The results demonstrated that the microwave-assisted combustion reaction was very simple and rapid to prepare 27-37.2 nm nanocrystalline pigments. Colorimetric results also indicated a broad reflectance band around 540 nm (green region) for all samples. It was deduced that the fuel-rich sample has more chromaticity and has a deeper green color.
Rapid synthesis of hydroxyapatite nanopowders by a microwave-assisted combustion method
Nagmeh Bovand,Sousan Rasouli,Mohammad Reza Mohammadi,Davood Bovand 한양대학교 세라믹연구소 2012 Journal of Ceramic Processing Research Vol.13 No.3
Nano bioactive hydroxyapatite (Ca10(PO4)6(OH)2, HAp) ceramic powders have been synthesized by a microwave-assisted combustion method. The powders were synthesized using calcium nitrate tetrahydrate (as the source of calcium) and sodium phosphate dibasic anhydrous (as the source of phosphate ions). Glycine, citric acid and urea were used as fuesl. The influence of the fuel type on the structure and morphology of the samples was studied. Results by X-ray diffraction and Fouriertransform infrared spectroscopy showed the formation of hydroxyapatite as a major phase for all the samples. Using the Scherrer formula, the average crystallite size was found to be in the range of 10 to 28 nm. SEM-EDX results showed highly crystalline nano-powders with an elemental composition of Ca and P in the HAp phase. The morphology of the particles was dependent an the fuel type and changed from semi-spherical to elongated. Smaller particles were obtained with glycine as the fuel.
Roohollah Azizi,Sousan Rasouli,Naghi Parvini Ahmadi,Amin Jafari jafar kolaei,Mohammad Azizi 한양대학교 세라믹연구소 2012 Journal of Ceramic Processing Research Vol.13 No.2
TiO2 nanoparticles were prepared by a sol-gel method using TiCl4 as a precursor. The effect of the TiCl4/H2O molar ratio and DBS/ethanol (two important parameters in this process) on the particle size and structure of the samples were studied. The structure and morphology of the nanoparticles were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. A systematic study was made by using the results of Design-Expert software. The optimum ratio of TiCl4/H2O and DBS/ethanol, to achieve the smallest particle size and the highest rutile content, were studied. Results showed that a lower TiCl4/H2O molar ratio led to smaller nano particles and that this goal is achieved for the lowest TiCl4/H2O molar ratio and intermediate DBS/ethanol values.