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TiO2 grain reunion was hindered, which maked the phase change activation energy increasing.
The increasing of the number of photogenerated-hole and hydroxyl radicals, so as to improve the efficiency of the photocatalytic reactions.
And grain size of TiO2 will become bigger after there times according to XRD spectrogram after roast.

The cathode material was TC11 alloy with fine -grained equiaxed structure, which includes ~ 88% Ti; 6.5% Al; 3.5% Mo; 1.5% Zr, and 0.3% Si (Wt).
However, on all samples coated with selected electrode materials there is no pronounced heat-affected zone in the substrate, characterized by a decrease in grain size of the matrix material, that usually appear under the surface layers due to exposure to high temperatures during electro-spark treatment [3].
During testing of the samples delamination of heat scale was not revealed, but increased the number and size of microcracks on a surface.

A representative volume is necessary to sample a statistically relevant number of grains contributing to the diffraction peak of the coarse-grained matrix.

The micrograph shows a pattern of constituents: (i) the dendritic structure of the weld metal (top), (ii) the coarse grained ferrite-pearlite structure, (iii) the fine grained ferrite-pearlite structure and (iv) the parent metal of deformed ferrite-pearlite structure (bottom).
In addition, there is an increased number of 180o domain walls in the tensile stress direction [9] which contribute to an enhanced signal.

These shapes of the macroscopic cracks were caused by inclusions (large grains) occurring in the concrete structure placed in the vicinity of the crack paths.
In case of the concretes FA-30 we observed the curving of the crack paths and a large number of branches.
Golewski, Effect of aggregate kind and graining on modeling of plain concrete under compression, Comput.

It produced a large number of asbestos tailings piling up mostly in the mining area, which not only caused great waste, but also bringed the pollution into the mining area of water, air and soil.
The traditional application of serpentine has relatively strict requirements of its grain size and chemical composition, for example the grain size of serpentine used as iron flux is 10-30mm, its MgO>38%; that used as refractory requires its MgO>40% and CaO<0.8%.Therefore,there would be a mass of serpentine tailings produced in the course of serpentine application.

With increasing the milling time, the number of phases was decreased and only Al2Y phase retained in the powder after milled for 100h.
For a phase transformation process related to nucleation and growth of grains, the JMA equation is a helpful tool to describe the corresponding transformation mechanism [13].
By this equation, we have the following equation in the non-isothermal condition, (4) where x(t) is the crystallized volume fraction at time t; is the Avrami exponent related to nucleation and growth of grains and is the reaction rate constant related to absolute temperature and activation energy; is the incubation time.

In the initial stage of tension of the sample, the grain slips, forming slip lines with different directions.
With the increase of deformation, the number of slip lines also increases, resulting in the gathering and entanglement of dislocation.
At the internal grain defects areas such as stacking fault and dislocation, the local stress continues to increase due to the functions of dislocation glide and deformation twins trimming.

Therefore possible changes of the grain structure can be limited to the locally heated forming zone.
The disadvantages are the thermal strains, the oxidation of the surface and the potential influence of the grain structure.
In the practical tests the laser power amounts up to 1000 W, the dimension of the laser spot is 7.6 x 3.8 mm², the number of courses is 36, the scanning frequency is 11 Hz.

Also, it has been demonstrated that the oxidation and spallation resistance and the thermal insulation capability of such TBC can be improved with the increasing of number of layers of the bond coat.
The improved strength can be attributed to that the submirco-sized YAG particles can inhibit the grain growth of Al2O3 grains.