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The grain structures of the hot bands were observed by optical microscopy (OM).
The grain size, precipitate size and distribution and the residual solute content were identified as important hot band parameters, influencing the recrystallization behavior of IF steels [8,9].
Steel TI-1, TI-2 and TI-3 had a similar hot band grain size, about 21 µm, 24 µm and 23 µm respectively, so the precipitate size and distribution and the residual solute content were expected to be responsible for the differences in the recrystallization behavior of the three steels.
N(R)dR is the number per unit volume of centers with typical size between R and R+dR.

The addition of Mn will segregation on the austenite grain boundary and suppress nucleation, which eases the requirement for cooling speed to some extent.
The higher cooling speed, the more martensite and finer grains[10].
Roller hearth furnace is a furnace that consists a number of parallel rollers.
When the forming temperature is too high, the austenitization degree is excessive resulting in the austenite grain coarsening.

It is worth noting that once a good dispersion of the particles is achieved, mechanical properties can be improved by reducing the grain size of the matrix and by work hardening.
It could be interpreted by considering that there could be a number of particles which do not effectively contribute to strengthening of the material.
Possible explanations are that these might be placed in correspondence of grain boundaries or might form small aggregates of few particles which are not as effective as the discrete ones.
Probably. this is due to the fact that these are placed at grain boundaries and some others form small clusters not effective as the discrete particles.

A large number of these operations in the manufacturing processes force suppliers to reduce costs and increase productivity while maintaining the required accuracy and quality of the preforms or of the finished products.
An abrasive with a grain size of 150 – 300 μm was used.
The grain direction in the material was not taken into account when cutting the specimen.
This resulted in the formation of cracks and their further spread along the grain boundaries.

In addition, there are factors, which directly influence the product quality, such as hardness, porosity, morphology, and size of grains and the binder to be used [9].
Proportions (binder [g]/ gypsum [g]) Binder % Particle size Hardness (N) 0.1024 0.1280 0.1536 Manioc starch 68.23819 63.13206 81.70426 12.96 - 9.074 0.0120 0.0250 0.0380 CMC 82.50309 84.42122 88.40889 4.971 2.186 1.456 0.0120 0.0250 0.0380 PVA 77.36050 78.98779 81.23549 3.829 5.036 4.310 The binder that had the best grain size was carboxymethylcellulose (CMC), as can be seen in Table 2.
Because the number of samples, it is possible to statistically analyze the resistance data.
The average strength to the grains that were used cassava starch was close to 1 kgf (about 10 Newton).

Designation: 1-6 - numbering of samples Result and Discussion The results of measurements of the conditional yield strength are shown in Fig.2, there is also shown the nature of the change in the hydrogen content along the cross-sectional thickness of reinforced concrete structures.
Studies of the structure of grain boundaries and areas around micro-ulcers have shown the content of corrosive agents in the working environment with which the reinforcement of reinforced concrete structures, which leads to loosening and weakening of the bonds between the grains and, consequently, to reduce crack resistance.
However, they can originate and develop in the body of grains.

Different scientific and technological studies are being conducted, both in academic and construction industry, aiming the development of new construction materials with properties that can decrease visual pollution of cities, reducing also the number of cleanings required.
A lot of scientific and technological studies are being conducted, both in academic and industrial areas, aiming the development of new materials with properties that can decrease visual pollution of cities, reducing also the number of cleanings required.
The crystalline grain size was calculated from the XRD pattern according to the Scherrer equation [27]
(1) where Dhkl is the mean grain size with crystalline planes (hkl), Bhkl is the WHPM intensity in radians, and l is the wavelength of the CuKa radiation source.
For the coated P-W sample, the TiO2 nanoparticles agglomerations are more homogeneous and exhibit clusters with smaller sizes (see Fig. 3(f)); therefore, as the grain size of these clusters is decreased, the surface-to-volume ratio is increased and the photo-generated electrons and holes could undergo a short pathway to migrate to the surface.

Therefore, the TiO2 films include a large number of C atoms may cause to decrease the transparent of TiO2 films, and -OH groups on the surface cause to unstable of the TiO2 films.
From the SEM images, it is found that the grain size increased with increasing the annealing temperature.
Fig. 4(a)~(d) show the microstructure of the surface that annealed from 200 to 900°C, the grain size of the TiO2 films were increased from 0.74 nm to 2.81 nm.

It can be seen that there are twins at the early stage, and with the increase of deformation degree, the density of twins increase which leads to grain refinement and carbide precipitation.
It can be seen that there are dislocation groups, stacking faults, crossing of stacking faults with twins and crystal grain be refined.
With the increase of deformation, a large number of high density deformation twins appear.

As visible light accounts for the large proportion of the solar spectrum, therefore, the development of visible-light-driven photocatalysts has become one of the most challenging topics recently.Rencently, a great number of novel semiconductor photocatalysts have been developed, such as BiVO4[10],InVO4[11], Bi2WO6 [12] and so on.
With further increasing temperature to 750℃, XRD patterns of the prepared samples showed sharper,which indicated a better crystallinity and increase in grain size.
Apparently, the crystal size of the samples increased with the calcination temperature, which implied that high temperature favored the stage of the grain growth according to the theory of thermodynamic nucleation and growth.