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As shown in the figure, the pattern of S1 can be indexed to the monoclinic Ba2MgSi2O7 structure according to the JCPDS standard card No. 10-0049.
The patterns of S2 and S3 can be indexed to tetragonal Sr2MgSi2O7 structure and tetragonal Ca2MgSi2O7 structure according to JCPDS standard card No. 75-1736 and 87-0052, respectively.
The coordination number of the M2+ (M: Ba, Sr, Ca) ion in all the samples is eight.
However, The numbers of coordinated neighboring oxygen ions are three from one layer and five from another layer in Ba2MgSi2O7, and four for each layer in (Ca, Sr)2MgSi2O7 [10].

The high magnification of field emission scanning electron microscope (FE-SEM) image in Fig. 1b clearly reveals that the flower like single particle consist of a number of branches, approximately ~ 200 nm in length and 100 nm in width of each.
No impurity peak is observed in each pattern by changing the w/e ratio, the sharp peaks matching with the standard JCPDS card #85-0443 indicating the CaWO4 crystals is well crystallized in this hydrothermal process.
Fig. 2 (a) XRD patterns of hydrothermal processed samples at 120 °C for 12 h in the mixture of water and ethanol with volume ratio w/e = 100/0, 75/25, 50/50, 25/75 and 0/100 and JCPDS card of CaWO4.
At the same time, a number of decomposed nanoparticles were observed in the product, and quite obvious in that of ethanol predominant sample F7, while amorphous particles were obtained.

All the peaks were indexed by comparing the XRD data with the standard JCPDS card No. 01-072-7678.
Peaks are labeled in accordance with JCPDS card No. 01-072-7678.
Trend of volumetric strain in crystal structure and porosity of pellets are shown with variation of sintering temperature where n is number of formula units in BFO hexagonal unit, M is molecular mass of one formula unit, V is volume of unit cell and NA is Avogadro’s number.

Although a number of synthetic methods have been developed to fabricate and assemble LaPO4 phosphors with various morphology, they often suffer from the requirements of high temperature, special conditions, tedious procedures, and templates or catalysts.
Therefore, the development of practical methods for fabricating a large number of phosphors with spherical morphology at low cost is still a great challenge for further study.
Figure 1 shows the XRD patterns of the as-obtained LaPO4 and LaPO4:Ln3+ microspheres and the reference JCPDS Card No.46-1439.
As shown in Fig. 1(a to e), all of the diffraction peaks for the samples can be well indexed as the hexagonal phase of LaPO4·0.5H2O, with lattice constants a = b = 0.710 nm and c = 0.6494 nm (JCPDS no.46-1439).

Precipitation of cristobalite was not detected under the present experimental conditions, indicating that the presence of Al2O3 inhibited the crystallization of the glass, which is in agreement with the results reported in previous works [20]. 0 30 60 90 120 150 0 5 10 15 800ºC 850ºC 900ºC 950ºC 1000ºC ∆∆∆∆l/lo (%) time (min) 0 5 10 15 0 5 10 15 Isotropic slope 800ºC 850ºC 900ºC 950ºC 1000ºC ∆∆∆∆l/lo (%) ∆∆∆∆r/ro (%) Fig. 5- Experimental and calculated values Fig. 6- XRD patterns for composites sintered of final relative density for composites at 800ºC and 1000ºC during 30 min and sintered at different temperatures 120 min (A-alumina, JCPDS card-10-173 [19]).
Figure 7(b) shows the micrograph of a composite after heating up to at 1000ºC, and it reveals a denser microstructure, where a large number of the pores have become closed due to capillary flow of the glass.
In fact, pore growth had occurred in the sample sintered for the longest time, and the number of closed pores exhibited by this sample decreased with increasing sintering time.
[19] JCPDS, Int.

JCPDS files were used to identify the peaks of main components in sample.
XRD peaks were broad and found to be similar to the characteristic pattern of hydroxyapatite (JCPDS card# 09-432).
Patient’s number Sex Age [years] Extracted site Causes/Indication 1 Male 45 #21 Endodontic failure 2 Male 43 #11 Endodontic failure 3 Female 37 #22 Complicated crown-root fracture 4 Male 33 #11 Endodontic failure 5 Female 39 #13 Root caries Fig. 2.
However, further study in larger number of patients is still needed to ensure its performance.

Results and Discussion structure and morphology Fig.1 shows the XRD of NaYF4:Er3+, Yb3+(a) and JCPDS card NO:77-2024.
The lattice constants of NaYF4:Er3+, Yb3+ are slightly smaller than the standards file number: 77-2042 values for pure α-NaYF4, a = b = c = 5.47 Å because of smaller size of Yb3+ (1. 042 Å) and Er3+ (1.062 Å) substituting for Y3+ (1.075 Å) in the mixed crystals.
Fig.1 (a) X-ray powder diffraction pattern of NaYF4:Er3+, Yb3+ powder,(b)X-ray powder diffraction pattern of JCPDS: 77-2042 Fig.2 SEM of NaYF4:Er3+, Yb3+ powder. upconversion fluorescence Fig.3 shows the room-temperature upconversion fluorescence spectrum of NaYF4:Er3+,Yb3+ material upon 980nm NIR excitation(continuous wave(CW)), there were three emission peaks at 522, 543, and 652nm, which assigned to Er3+ transitions from 2H11/2, 4S3/2, and 4F9/2 to the ground state, respectively.
The relationship between pump power and emission intensity can be approximately expressed as follows: Iout∝ (Iexc) n, where n is the number of infrared photons absorbed for emitting a visible photon.
In this double log representation the number of photons involved in the excitation process can be deduced from the slope.

The identification of the diffraction peaks was done by comparing the XRD spectra with the JCPDS database.
The obtained diffraction spectra graphite matches well with JCPDS card number: 41-1487.
The defects can be related to several features: the presence of edges in small crystals, deviations from planarity, the presence of a certain number of Carbon atoms in the sp3 hybridization state, etc.

The main characteristic diffraction peaks can be indexed as a pure cubic phase (space group Ia3 (206)) with cell parameter a=10.66 Å, in agreement with the standard values for bulk cubic Y2O3, card number JCPDS 41-1105.
Accordingly, the d-spacing were 0.213 nm, 0.206 nm and 0.178 nm that correspond to (2 2 4), (-1 4 -3) and (1 6 1) planes and [-11 1 5] direction, of cubic Y2O3 phase (JCPDS card number 41-1105).

Joint Committee on Powder Diffraction Standards (JCPDS) reference cards were used to identify the purity of the samples.
The reference numbers used are as follow: forsterite (00-034-0189), periclase (00-043-1022) and enstatite (00-011-0273).
L is the average interception length, C is the total length of the test line, M is the magnification of SEM and N is the number of intercepts [10].
All peaks shown in the XRD corresponded well with forsterite phase and no secondary phases was observed when compared to the reference cards listed.
Acknowledgements This study was supported under UMRG grant number RP024B-13AET, UMRG grant number RP011B-13AET, PPP grant number PG129-2014A and Esciencefund grant number SF010-2014.