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The direct band gap, refractive index, extinction coefficient and grain size were investigated.
A number of techniques such as sol-gel [10], liquid deposition method [11] and sputtering [12, 13] can be used to deposit TiO2 films.
The mean grain size increases slightly, from about 20 to 25 nm, with increasing the annealing temperature.
This is due to the fact that smaller grains tend to have surfaces with sharper convexity and gradually disappear by feeding the larger grains, as annealing temperature increases [19].
The calculated grain size is in agreement with the data estimated by other researchers [20-22].

Because of the inherent anisotropy of the hcp structure and a limited number of slip systems, texture is developed in Zircaloy tubing depending on the fabrication details.
The material variables include crystal structure, alloying content, second phase particles, and initial grain size.
The main difference between the microstructure of CWSR and Rx Zircaloys is their grain shape.
CWSR has an elongated grain structure whereas Rx material has an equiaxed grain structure.
The grains are elongated in the θ-plane, and the grain boundary separations are very small in the z-plane.

Motivated by those excellent applications of Ti02, an increasing number of, researchers have engaged in the fabrication of Ti02.
As it can be seen , the surface is full of domed grains.
By increasing annealing temperature to 393K and in presence of uniform oxygen flow(8 Cm3/sec), oxygen will penetrate to the grain structure and brake them down to tiny needle like grains (Figure1(b)).
By increasing annealing temperature, roughness is also increasing and this is because of penetrating oxygen to grain structures and migration of grains in higher temperatures.
By increasing annealing temperature and presence of oxygen flow, in the first step oxygen penetrate to grains and brake them down to needle like grains, by increasing heat the penetration of oxygen will continue and because of surface diffusion roughness will change, there are still needle like grains on surface.

The twin-roll casting (TRC) process creates semi-finished products of magnesium alloys like near-net-shape strips and wires by a reduced number of process steps /2/.
After subsequent annealing the eutectic phases are dissolved, the material is homogenized and a fine grain structure develops.
The grain refining of the microstructure is a result of the plastic deformation during twin-roll-casting and the incipient recrystallization during annealing.
After rolling plus annealing a very fine grained, homogeneous microstructure has been realized with mean grain sizes as small as 5 µm.
In addition, all of the alloys experienced extremely fine-grained microstructure resulting in good mechanical properties.

For polycrystalline materials, for example the grain corners can act as preferred nucleation sites.
stress, MPa average grain diameter, μm 0.30 59.4±3 0.50 57.9±3 0.90 56.4±3 1.20 54.8±3 Table 2 The average grain diameter of Fe-2.96 at.% Ni specimens under various compressive stresses during the g®a transformation[15].
The average grain size of all initial specimens is 65.7±3 μm.
The nucleus density is estimated from the number of product grains, assuming that (only) one nucleus is the origin of each product grain; thus N*=.
It is experimentally very difficult to measure the grain size of the austenite at high temperature.

Grain.
The grain of powder is tested by SA-CP3centrifugal settling granulometer.
The grain, which is tested by the method of centrifugal settling, is reunited?
The diameter of primary grain obtained is 10nm by calculating XRD analysis's data.
(a, left) Cumulative graph of grain; (b, right) Differential graph of grain

All solutions are substitutional (number of atoms per cell is equal to 4.000+0.001.
In all cases, the number of atoms per elementary cell is 2.000+0.001, that means a substitutional BCC solid solution.
In a certain sense, the obtained nanocrystalline structure is "virtual", since after gradual uniform decompression the number of grains decreases.
Thus, the monocrystal becomes a polycrystal, with the number of grains less than in the compressed state.
Further formation of nanocrystalline structure with larger extent of off-orientation of grains is observed.

Content average of grain size greater than 0.50mm is 51.04% of the total weight.
The sixth layer pebble (Q4al): Variegated, saturation, moderately dense, conglomerate composition are almost limestone and sandstone, sub-circular, sorting quality is moderate, sandy and muddy soil fill it, conglomerate grain size is generally among 30~80mm, the content average of the grain size greater than 20mm occupies 55.80% of the total weight.
The eighth layer pebble (Q3al): Variegated, saturation, moderately dense, conglomerate composition are almost limestone and sandstone, sub-circular, sorting quality is moderate, the middle coarse sand fills it, conglomerate grain size is generally among 40~150mm, the content average of the grain size greater than 20mm occupies 57.00% of the total weight.
Table 2 Statistics of grain analysis and clay particle content of each layer of soil (average) (%) Layer number >20[mm] >2[mm] >0.5[mm] >0.25[mm] >0.075[mm] >0[mm] Clay particle content (%) ③ 14.80 ④ 14.10 ⑤ 12.8 31.3 36.2 13.6 6.1 45.1 21.5 16.4 11.2 5.8 55.8 24.5 14.4 5.3 57.0 23.5 14.9 4.6 Hydrogeological conditions of the site.
According to statistics, the use of post-pressure grouting technology can increase single pile capacity by 35% to 110% (increase extent of fine-grained soil is a lesser extent), under the conditions of correspondingly reducing the number of piles, it can reduce the building total settlement by 25% to 55%, and can significantly reduce the geologic differential settlement.

Pure Al powder (89µm average grain diameter) and pure Cu powder (106µm average grain diameter) were used as the additives.
Figure 4 shows the effect of the number of processes on the tensile strength (Cu powder).
Figure 6 shows the effect of the number of processes on hardness distribution (Cu powder).
Fig.6 Effect of number of processes on hardness distribution (Cu powder).
A uniform dispersion of the Cu particles was observed and the particle size was smaller than the starting Cu powder (average grain size: 89µm) in both cases.

With hydrogen content of increasing, the number of pores and the porosity showed a decreasing trend, the density of sintered body showed an increasing trend.
The number sintered body pores of TC4 powder with hydrogen content of 0.42 wt% was a minimum, the lamellar and needle-like structure was the thinnest, and the duplex structure was the maximum.
With hydrogen content increasing, the recrystallization appeared in grains of sintered body, grains boundary become vague, grains occurred breaking, new grains boundary become clear, duplex grains become more and more, grains size become smaller.
The consolidation processing utilized alloying effect of hydrogen atom to improve physical characteristics and mechanical properties，advance atomic grain diffusion of titanium alloy powders.
All of the phase transitions were favorable for recrystallization and grain size breaking of sintered body of hydrogenated titanium powder by die forming and sintering, as well as, it make for the sintered body has low porosity, refinement microstructure and higher performance.