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It can be assumed, that as reduction of particle size leads to increase contact number between grains and, concurrent decrease in pore size.
Accordingly, with the number of pores increase, their size tends to reduce.
With reduction of particle size, the number of contacts between grains increases and pore size decreases.
When using chalk-stone filler with the highest grain fineness in the bitumen-mineral composite, a matrix with a high density and nano-sized pores can be formed.
Gömze, Influence of composition and grain size distribution on the properties of limestone and dolomite asphalt fillers, Materials Science Forum. 729 (2012) 344–349 [9] R.

SEM images indicated the small grain size of samples with x=0, 0.2.
The FTIR spectra in the wave number range from 400 cm-1 to 4000 cm-1, were obtained by the KBr pellet technique.
Since the citric acid to total cations molar ratio is fixed to 2, higher strontium content means greater excess of citric acid due to the lower oxidation number of strontium compared with that of lanthanum.
Calcination at higher temperatures leads to the evolution of grain size without altering the crystal structure of the products.
Both samples consist of spherical particles with grain size lower than 100 nm.

The results suggest that when the SiH4 and NH3 are used as the precursors, Ar is used as the protect gas, H2 is used as the carrier gas, the flow amount of SiH4 and NH3 is 200 sccm and 1000 sccm, the reaction pressure is 100 Pa, the reaction temperature is 900 oC and the deposition time is 30 min, the silicon nitride coatings with high deposition rate (~ 85 Å/min), small grain size (~ 0.2 µm) and high density are obtained.
When R is 5.0, with the deposition rate going on decreasing and the molecule increasing, the number of the insular structure of the initial nucleation is increasing and the combination rate is slowing down.
The results suggest that when the SiH4 and NH3 are used as the precursors, Ar is used as the protect gas, H2 is used as the carrier gas, the flow amount of SiH4 and NH3 is 200 sccm and 1000 sccm, the reaction pressure is 100 Pa, temperature is 900°C and deposition time is 30 min, the amorphous silicon nitride coatings with high deposition rate (~85Å/min), small grain size (~0.2 µm) and high density are obtained.

The annealing treatments have been often employed to reduce the defects and enlarge the grain size for more desirable crystalline structure.
A number of methods such as chemical vapor deposition [4], sol-gel [5-7], spray pyrolysis [8-9] and sputtering [1-2] have been used to prepare ATO thin films.
In order to improve the electrical and optical properties of ATO thin films, the annealing treatments have been employed to reduce defects and enlarge the grain size for more desirable crystalline structures [11].

The results indicate that the kaolin benefits the reduction of the shrinkage and may have negative effect on the formation of glass-ceramics with fine grained crystallites.
The glass frit derived from sample M8 which was numbered in ref [15] was used in this study.
Fig. 3 SEM micrographs of the glass- ceramics with binders: K5 (a); K10 (b); P5 (c); P10 (d); S5 (e); S10 (f) The SEM images depicted in Fig. 3 suggest that the prepared glass-ceramics consist of fine-grained crystals dispersed among glassy matrix.

Three responses tensile strength, average microhardness at weld nugget zone (WNZ) and average grain size at WNZ have been selected.
Table 1 Process parameters and their levels Symbol Parameters Unit Levels 1 2 3 N Tool rotational speed rpm 700 900 1100 S Welding speed mm/min 40 60 80 D Shoulder diameter mm 15 18 21 d Pin diameter mm 4.5 5 5.5 Tensile strength (TS), microhardness (MH) at WNZ and grain size (GS) at WNZ have been selected as responses.
Parameters TS [MPa] MH [Hv] GS [μm] N S D d 1 1 1 1 1 136.2 59.53 19.886 2 1 1 2 2 146.3 69.84 15.625 3 1 1 3 3 141.1 64.03 16.203 4 1 2 1 2 145 66.74 16.509 5 1 2 2 3 150.2 73.4 10.937 6 1 2 3 1 143.7 65.88 16.826 7 1 3 1 3 135.1 54.14 19.021 8 1 3 2 1 138.8 62.09 18.657 9 1 3 3 2 139.6 62.53 18.121 10 2 1 1 2 148.8 69.23 14.583 11 2 1 2 3 153.5 76.41 11.82 12 2 1 3 1 152.6 68.77 14.112 13 2 2 1 3 150.9 75.54 11.217 14 2 2 2 1 161.2 85.25 8.578 15 2 2 3 2 156.1 78.56 9.943 16 2 3 1 1 146.3 62.71 18.229 17 2 3 2 2 151.3 72.87 12.323 18 2 3 3 3 145.2 65.14 18.229 19 3 1 1 3 145.4 69.92 13.257 20 3 1 2 1 151.2 73.22 12.86 21 3 1 3 2 143.9 72.43 12.152 22 3 2 1 1 150.1 71.21 13.67 23 3 2 2 2 157.5 79.39 9.72 24 3 2 3 3 152.5 76.36 11.513 25 3 3 1 2 137.5 66.54 17.156 26 3 3 2 3 147.5 72.15 12.152 27 3 3 3 1 142.5 62.45 17.5 Modeling ANN Modeling ANN is information processing architecture in which a large number of highly interconnected neurons are working together.

Level factor A:Ce-doped x B:sintering temperature /℃ C:sintering time /h 1 A1=0.04 B1=1400 C1=2 2 A2=0.05 B2=1500 C2=3 3 A3=0.06 B3=1600 C3= 4 Tab.1 Levels of factors Number A:x B:T[℃] C: t[h] color purity /[%] Precipitation 1 1[0.04] 1[1400] 1[2] 80.5 Precipitation 2 1 2[1500] 2[3] 65.9 Precipitation 3 1 3[1600] 3[4] 59.5 Precipitation 4 2[0.05] 1 3 76.0 Precipitation 5 2 2 1 71.0 Precipitation 6 2 3 2 21.5 Precipitation 7 3[0.06] 1 2 83.5 Precipitation 8 3 2 3 69.1 Precipitation 9 3 3 1 34.9 Mean R1 68.6 80.0 62.1 Mean R2 56.2 68.7 57.0 Mean R3 62.5 23.2 68.2 Range Rj 12.4 56.8 11.2 Tab.2 orthogonal experiment According to Table 2 range Rj size, regarding in luminous powder sample spectrum performance excitation purity, various factors' influence order is: The sintering temperature B>Ce doping measures [x] A> sintering time C.The smaller of the color purity, the better of the yellow phosphor and blue light LED match.
Results and discussions Analysis of grain size and morphology of the sample Figure1 is the scanning electron microscope photos of YAG: Ce3+ at different roasting temperature, according to figures: the higher the temperature, the more apparent.
This is because the samples of yttrium oxide has a high melting point, when the temperature rises to raw material melting, conducive to the growth of grain size, and eventually form a large particle.
Therefore, appropriate to reduce the sintering temperature can avoid that grain is too large or reunion, the best synthesis temperature of this experiment is 1600℃
It cause that the crystal grain tends to be complete, reduced the surface defect and hanging the key, promotion activator ions Ce3+ enters in the crystal lattice to form the luminescent center, causes between the preparation process intermediate ion the response to carry on completely, thus enhanced the luminous powder YAG:Ce3+ luminous intensity.

So, the scholars have performed a large number of experimental studies on the test method of filling capacity.
Fig. 2 Fluidity test apparatus: A-stopper rod, B- pouring cup, C-sand mould, D-metallic clamps, E-cylinder They also applied this device to study the effect of grain refinement on the fluidity, and compared the grain size of the base and the tip of the same spiral sample.
No statistically significant effects of grain refiner addition on fluidity are revealed, but there is a grain size reduction of the spirals from the base to the tip.

When adding 0.5Cu into the alloy, a number of Cu-rich intermetallics were presented as irregular morphology in the microstructure.
It is seen the obvious precipitation occurred in the Al grains after ageing heat treatment.
Conversely, when the Cu phase is presented as a continuous network at grain boundaries, limited strength enhancement can be achieved with a severe reduction of the ductility [[] L.
In the as-cast Al-Mg2Si-Mg-Mn alloy, the majority of Cu-rich intermetallics are found along the grain boundary and sharp irregular shapes.
The quick T6 heat treatment can dissolve the majority of Cu-rich intermetallics during solution treatment, which are subsequently precipitated in the aluminium grains during ageing.

The micro-strain refers to the strain between adjacent grains and the random strain within grains.
The macro-strain is a more homogeneous quantity and is on a larger scale involving many grains, i.e., the residual stress.
Hydrogen trapped in the lattice can diffuse freely in the metal and concentrates around inclusions, grain boundaries, dislocations and at the tips of cracks [1].
This work was partly supported by JSPS KAKENHI Grant Number 24360040, 25820001 and JFE21st Century Foundation.