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Effects of Thermal Treatment on the Structure of Eu:YAG Nanopowder Maria Luisa Saladino 1,a, Eugenio Caponetti 1,b and Stefano Enzo 2,c 1 Dipartimento di Chimica Fisica "F.
Annealing temperatures higher than 950°C and holding times longer than 3 hours were necessary for the complete formation of the Nd:YAG structure.
It can be easily recognized that the patterns are entirely ascribable to a cubic garnet structure [13].
Acknowledgments The authors would like to thank JEOL for FEG-SEM and TEM measurements and MIUR (Ministero dell'Istruzione, dell'Università e della Ricerca) for supporting this research through the PRIN 2004 prot. 2004033823823 and Palermo's University: "Chemical processes under magnetic field irradiation for sustainable chemistry".
[13] Inorganic Crystal Structure Database, Information on http://icsdweb.FIZ-Karlsruhe.de

A quantitative structure property relationship (QSPR) model is established for estimating aqueous solubility (log SW) of PCDD/Fs.
Three-dimensional holographic vector of atomic interaction field (3D-HoVAIF) is used to describe the chemical structures, the correlation between the 3D-HoVAIF descriptors of PCDD/Fs and aqueous solubility (log SW) was established by partial least square (PLS) regression.
The quantitative relationship between the structure and aqueous solubility of PCDD/Fs has been studied by several groups [3-6].
In this study, 3D-HoVAIF method is used to describe the chemical structures, SMR-PLS QSAR model has been created and good correlation coefficients and cross-validated correlation coefficient is obtained.
Calculation for 3D-HoVAIF descriptors of PCDD/Fs Original spatial structures of the 212 PCDD/Fs molecules are autogenerated by software Chemoffice 2004, and then optimized preliminarily using semi-empirical quantum chemistry soft MOPAC in Chem 3D at AM1 level (energy cut-off:0.001 kJ·mol-1).

A gas-solid reaction method was adopted in this work to explore the influence of SO2 gas on the composition and structure of secondary sintering cement clinker.
The crystal structure of alite in clinker was characterized by XRD analysis, and the transformation of crystal structure during the experiment was distinguished.
By using the X-ray diffraction analysis, this paper studied the phase types and crystal structures of cement clinker at the secondary sintering temperatures of 600, 700 and 800 degrees.
As the temperature increased, the crystal structure gradually changed from M3 type to M1 type, as shown in Fig.2.
[9] H.F.W Taylor, Cement chemistry/2nd ed, Thomas Telford, London, 1997

Hydrothermal Synthesis of Na(Nb1-xTax)O3 Powder for Fabrication of Lead-Free Piezoelectric Ceramics Kongjun Zhu1,2, a, Jinhao Qiu 1 , Koji Kajiyoshi 3 and Kazumichi Yanagisawa3 1 The Aeronautical Key Laboratory for Smart Materials and Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, P.R.China 2 Institute of Fluid Science, Tohoku University, Sendai 980-8577, Japan 3 Research Laboratory of Hydrothermal Chemistry, Kochi University, Kochi 780-8520, Japan a kjzhu@nuaa.edu.cn Keywords: Hydrothermal Synthesis; Lead-free; Piezoelectric; Ceramics Abstract.
The results indicate that the pure Na(TaxNb1-x)O3 (x = 0.1-0.5) powders with perovskite structure and fine particles were successfully synthesized by hydrothermal method at 240 ºC for 8 hours with the addition of isopropanol.
The pure Na(TaxNb1-x)O3 powders with perovskite structure were synthesized successfully when the NaOH concentration is higher than 2 M.
Summary The fine Na(TaxNb1-x)O3 powders with perovskite structure were successfully synthesized by hydrothermal method at 240 ºC for 8 hours under the low NaOH concentration with the addition of isopropanol.
Kan: Procedding of the 2th International Conference on Smart Materials ＆ Structures in Aerospace Engineering, ( 2006). p. 32

TEM imaging, is complement analysis tools are important for the development of nanowire-based structures and devices.
Fig. 2(b) clearly illustrated the core and shell structure of the nanowire with their diameter being approximately about 13 nm and 83 nm respectively.
The HRTEM image near the edge of the core reveals a single-crystalline structure with surrounded mainly by amorphous shell as clearly depicted in Fig. 2(c).
This single crystalline Ni2Si structure was further revealed by a Fast Fourier Transform (FFT) image, as shown in the inset.
Rahman, Study of the growth, and effects of filament to substrate distance on the structural and optical properties of Si/SiC core–shell nanowires synthesized by hot-wire chemical vapor deposition, Materials Chemistry and Physics 147(3) (2014) 974-981.

Lithium vanadium phosphate is NASICON structure.
The more commonly used are monoclinic structure as shown in figure 2.
In this structure, there are six phosphate tetrahedra around each metal surface of the body eight, around each phosphate tetrahedron with four metal surface of the body eight, this configuration to form a A2B3 unit in three-dimensional network structure with space group.
Cell collapse causes the structure becomes unstable, so that is not conducive to the lithium ions in the charge and discharge process in the three-dimensional structure of dropping into and block out, thus worsening the electrochemical properties of cathode materials.
Enhancing electrochemical performances of lithium ion battery using mesoporous Li3V2 (PO4) 3/C microspheres [J].Journal of materials chemistry, 2012, 22 (13): 5960-5969 [5] K.

a*imad.usm.iq@gmail.com, bhuda.nagem904@gmail.com Keywords: SnO2-Y2O3, Tetragonal rutile structure, polycrystalline.
The crystallization of SnO2-Y2O3 film with tetragonal rutile structure was achieved when the film was exposed to annealing at 500 oC.
Small nanoparticles were observed when the sample exposed to anneal at 500 oC, and the thin film was polycrystalline with uniform structures, as shown in Figure. 2.
Detailed structural characterization showed that the annealed film at 500 oC for 2h in air is tetragonal rutile structure.
Chemistry of Materials 17.15 (2005) 3997-4000

Surface analysis revealed that a surface structure of fine Ni-Fe particles dispersed on carbon nanofibers was formed on the foil during the reaction.
The activity is attributed to the formation of this fine structure.
These results suggested that Ni3Fe structure might be kept during methanol reaction.
The catalytic activity was attributed to the formation of this fine surface structure
Hirano, Journal of Physical Chemistry C, 114 (2010), p. 6047.

Synthesis and fluorescence properties of water-soluble L-cysteine-modified ZnSe:Ag quantum dots Liping Lin1,2,a, Fenghua Huang1,b,* Peifeng Chen1,c 1.College of Chemistry and Chemical Engineering, Fujian Normal University, Fuzhou 350007, P.R.
The crystal structure and optical properties of the obtained ZnSe:Ag quantum dots have been characterized by X-ray power diffraction, infrared spectrum, UV-Vis absorption spectrum and photoluminescence spectrum.
Results indicate that ZnSe:Ag quantum dots belong to the cubic blende structure and have good fluorescent characteristics.
No diffraction peaks of silver impurities were detected, the Ag+ doping into the host QDs does not lead to a phase transformation of the crystal structure [12].
XRD result shows that ZnSe:Ag QDs belong to cubic zinc blende structure.

The experimental results indicated that the MAO coating, with rough surface, high hardness and typical porous ceramic structure, is mainly consist of Al2O3, SiO2 and Al2SiO5 phases.
The surface morphologies of the coating were evaluated by scanning electron microscopy (SEM, Qunta2000).The chemical compositions and the phase structures of the coating were analyzed by an energy dispersive X-ray spectrum (EDX, EDAX- 7760/68 ME) and a X-ray diffractometer (XRD, Phlips X'Pert PRO).
The surface of the coating appeared many crater-like cavities and presented in a typical porous ceramic structure (see Fig.3(a)).
But some peaks of different phases were coincided at together, so it was necessary to measure by the x-ray photoelectron spectroscopy (XPS) of coating in order to analyze surface chemical states of these elements and determine phase structure of the MAO coating. 30 40 50 60 70 80 90 0 1000 2000 3000 4000 ---Al2O3 ---Al ---Si ---Al3.21Si0.47 ---SiO2 ---Al2SiO5 Intensity 2θθθθ / deg Fig.4 XRD spectrum of the MAO coating Fig. 5 exhibits the full scanning XPS spectrum of the surface of the MAO coating.
Therefore, not only nonferrous metals element (Al), but also nonmetal element (Si) was oxidized during the micro-arc oxidation process, which was important significance to realize the reaction mechanism and performance of the MAO coating. 1000 800 600 400 200 0 0 10000 20000 30000 40000 50000 60000 Al2s Mg2p Si2p Si2s Na(A) C1s Mg(KLL) O1s CPS Binding Energy (eV) Na1s O(KLL) Fig.5 Full scanning XPS spectrum of the surface of MAO coating 540 536 532 528 524 520 6000 8000 10000 12000 Intensity (Test curve) Peak Sum (Fit curve) Background Peak 1 (532.508eV) Peak 2 (531.332eV) CPS Binding Energy (eV) O1s Fig.6 High-resolution narrow scanning XPS spectrum for O1s of the surface of MAO coating Table 1 Compare between tested and standard binding energy of element on MAO coating surface Chemistry element Tested XPS spectra Binding energy [eV] Standard XPS spectra[23] Binding energy [eV] Chemistry form O1s 532.508 532.50