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It is seen that a number of recrystallized grains began to appear in the deformation bands after annealing at 150°C for 120min in both non-fileld and field-treated specimens.
Compared with the non-field annealed specimen (Fig. 1(c)), more recrystallized grains were observed in the field annealed specimens (Fig. 1, (g)).
When the annealing temperature came up to 300°C, the entire specimens were recrystallized showing an equiaxed grained microstructure (Fig.1 (e), (i)).
The grain size of magnetic field annealing specimens was larger than that without field treated.
Molodov, Magnetically affected recrystallization and grain growth in non-ferromagnetic metals, Materials Science Forum. 558-559 (2007) 649-656

Introduction In the process of studying the broken test about the hydraulic model experiment，there will produce a great deal of silt grain and the silt grain enters the circulatory system of water in the laboratory along with the water current, the direct result that it seizes the reservoir capacity, attrition the instrument and thus the result is in the economic loss.
Because the grain-size is the more thick, the sedimentation velocity is the more quick.
It reflects the physics quantity of the factor synthetically ，including the sediment shape , the size of the grain-size, the specific weight, the drag force of the current, the dynamical coefficient of viscosity of the water etc.[2].
The reason of the Resulting this phenomenon, , the current velocity is relative slower, the water current flushes only the some fine soil of the surface on the upper soil layer ,so the water takes the less sediment quantity and the grain-size of sediment is also smaller.
So, how much the sand carrying capacity of the water running off the sedimentation basin in comparison with the going into the sedimentation basin, but can't analysis the percentage of the grain-size settled in the each sedimentation basin [5,6,8].

The thick soil layer with hot rainy season in China makes the land the most prolific farming area and the commodity grain base here has played a vital role to the nation’s food security.
Soil degeneration in this area is getting serious all the time, restricting the economic development in North-east China and the nation’s grain production.
The purpose is to reduce multiple variables to a lesser number of underlying factors that are measured by the variables.
Acknowledgements This work is supported by the Natural Science Foundation of China (grant number: 40672180, grant number: 40911120044) .And the authors would like to thank PH.D.
Interdisciplinary Research Plan Project of Jilin University (grant number:2011J014) for providing financial support for this study.

Nucleation of ferrite takes place at an austenite grain boundary.
Growth then occurs either to polygonal ferrite (lower grain) or to bainite (upper grain) depending on the alloy content and cooling rate • In most cases, nucleation is dominated by processes occurring at grain boundaries.
The lower grain in Fig.1 shows this situation schematically.
The full range of predicted components is not seen, especially in the case of the bainite, which has led to the realisation that variant selection is taking place, which reduces the number of transformed orientations.
The rapid cooling produced fully bainitic structures in all cases and the resulting textures show increasing sharpness as the stress level increased, as expected from a smaller number of transformed variants.

The presence of a large number of M-A islands reduced the ductility of the steel.
Another factor exerting influence on the morphology of bainite is the size of the prior austenite grains, observed to be very different.
Beside large, elongated grains, in the direction of the growth of column crystals, small, equiaxed grains located on the boundaries, were observed.
The austenite grain size (AGS) influences primarily the kinetics of bainitic transformation [6].
Owen, The effect of austenite grain size and temperature on the rate of bainite transformation, Met.

HR-TEM investigations exhibited that an ultra-fine scale distribution of grains in Al 5083 matrix phase.
The high magnification micrographs revealed a fine grained microstructure with the trapped ultrafine intermetallics and the networked dislocations.
A typical grain of Al 5083 matrix phase resolved at lattice scale showed the arrangement of (111) planes throughout the microstructure as shown in Fig.2(c).
Significant enhancement in hardness and strength values were observed with nano-sized SiCp reinforced nanocomposite which could from the dislocation pile-ups by orowan strengthening mechanism [7] at grain boundaries and the solute segregation/reinforcements accumulation resulted in solute-drag at the grain boundaries.
Sampaolesi, “The influence of grain size on the mechanical properties of nanocrystalline aluminium”, Nanostruct.

Peaks corresponding to Bi-2223 phase decreased in number and intensities.
Any exchange of oxygen trough diffusion into the unit cell at the grains, need to come across the grain boundaries.
Therefore, the concentration of oxygen at the grain boundaries may be higher than inside the grains.
The improvement of the grain boundary should enhance the Jc of the sample.
From SEM images, the pure sample showed better grain connectivity compared substitutions samples.

Figure 2 shows the grain size of the films as function of substrate temperature.
The grain size increases with the increase of Ts.
Due to the enhanced degree of crystallization and larger grain size with higher temperature which is shown in figure 2, the grain boundary scattering, lattice defects and electron traps were reduced.
In addition, a large number of adsorbed oxygen at low temperature act as electron trap to capture free electrons, so the carrier concentration decreased near the grain boundary of the film.
This is because that high temperature causes variation of the grain orientation leading to more grain boundary defects and larger grain boundary barrier.

The total number of tests for each fiber type varied from 20 to 30.
As we know, the creep behavior of SiC-based fibers can be explained by their oxygen content, grain size and second inclusion in the grain boundaries.
For the intrinsic factors, when the fibers tested in low oxygen partial pressures, the grain growth/coarsening will occur due to coalescence of β SiC grain [11].
The grain size calculated from the XRD data for HNL indicated that grain growth began at 1573 K, and grain size increased with increasing the temperature and decreasing oxygen partial pressure.
As to TySA fiber, the grain size is almost no change because this fiber type initially has large grain size.

It can refine grain and improve strength and toughness of the material.
Figure 4C showed that cracks developed along the grain boundary.
Figure 4D showed some grain boundary cracked in segregation area and micro-cracks formation.
Grain boundary was coarse in segregation area.
The low Mo, V elements content lead to weaken the effect of grain refine.