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When the molding pressure is 30MPa, the holding time is 10min, the sintering temperature is 900℃, the holding time is 1h, the prepared Al2O3-Al cermet adding sintering aids has a coated microstructure, which indicates that the large number of particles is migrated on the grain boundary.
When the mass transfer process continues, the grain boundaries will become larger, resulting in contraction of the hole deformation.
The final pore will close and become isolated, at this time, the grain boundaries within the grain will gradually begin to move.
And the prepared Al2O3-Al cermet adding sintering aids has a coated structure, which indicates that the large number of particles is migrated on the grain boundary during the sintering process, it improves to form the coated particles, the particles and particles effectively bonded to enhance the sample all aspects of performance.
When the molding pressure is 30MPa, the holding time is 10min, the sintering temperature is 900℃, the holding time is 1h, the prepared Al2O3-Al cermet adding sintering aids has a coated microstructure, which indicates that the large number of particles is migrated on the grain boundary.

This study shows that ore grain shapes have a great influence on breakage rate due to different impact energies in ball mill.
In view of a number of different energy levels of impacts which occur in ball mill grinding process, Eq. 1 can be written for a series of successive impacts with the different impact energies as Eq. 2
(2) From Eq. 2, it can be known that the impact energy distribution of grinding media to ore grain must be got in order to gain breakage rate of ore.
It is assumed that impact intensity and corresponding impact number which were suffered by each ore grain in ball mill are same.
Conclusions DEM simulations of grinding different shape ore grains(sphere, regular tetrahedron and parallelepiped)in ball mill were carried out separately.

The packing of the grains (particles) is specified by the grain diameter, their mixing ratio and partial overlapping due to sintering [13].
Figure 2 Change in Knudsen number with pore size Transitional diffusion will occur when the pore size of the catalyst is less than 800nm and greater than 1.8nm.
The point of using bidispersive and bimodal catalyst grains is to upgrade the efficiency of the process.
The efficiency of the catalyst grain depends upon the choice of pore radii, upon the ratio of wide pores to narrow pores and upon the radius of the grain itself.
These particles make up the grains of the final catalyst.

It has also revealed that the size of an austenite grain and nonmetallic inclusions on grain boundaries are reduced, and sulphide inclusions are partially dissolved, which has a positive impact on the operation characteristics of the steel.
Under modification of steel we understand obtaining ingots and castings with a fine-grained structure.
The following changes in the structure of the samples were observed: after the modification the grain size decreased, while the size of the grain boundaries increased, which reduced the quantity of inclusions on the grain boundaries.
In addition, the carbide inclusions in steel disappeared after the modification; and the number of nonmetallic inclusions decreased.
The structure contained minor nonmetallic inclusions on the boundaries and inside the grains (Sample № 642, Fig. 2).

This can be due to a number of different mechanisms such as changes in vacancy concentrations or movement of structural defects.
In all cases the dynamic precipitate volume fraction is observed to increase approximately linearly with the number of cycles (and therefore with strain).
Figure 4: Difference in SAXS integrated intensity between the head and gauge of the fatigued specimens as a function of the number of fatigue cycles, plastic strain amplitude and fatigue frequency. 4.
After ageing three major facts are observed: -i- some coarsening of the grain structure; -ii- formation of coarse precipitates on the grain boundaries; -iii- persistence of numerous extremely small particles at the core of the grains.
Therefore, this evolution can only be due to the sweeping of the matrix by the recovering microstructure during ageing [10] (sub-grain and grain boundaries), as it was observed that the microstructure had somewhat coarsened after ageing at 100°C.

This is however connected with a risk of impetuous grain growth.
Obviously, this involves a risk of austenite grain growth during the process.
In order to determine the effect of the process temperature on the austenite grain size and the action of ammonia, the grain size of the former austenite was measured by the method of counting the grains cut by the measuring section of a straight line (according to PN-EN ISO 643).
The difference in the grain sizes obtained at 920°C and 1000°C amounts to about 16.5%.
In consequence, it is possible to perform in a furnace higher number of processes within time unit.

However, grain refinement increases grain boundary area, raising the probability of microcrack intersection and thereby producing a larger number of small fragments.
Carbide precipitates can further reduce effective grain size from a fracture standpoint, enhancing fragmentation.
On the y-axis, the “fragmentation metric” (e.g., average fragment count or a combined index reflecting mass distribution and fragment number) has been empirically determined under explosive loading.
Tests show that shells cast with higher Ny values exhibit fewer internal defects and microcracks, which reduces the total number of fragments formed.
High-carbon steels with a fine-grained microstructure tend to undergo transgranular cleavage, producing a larger number of smaller fragments with higher velocities, while coarser microstructures promote intergranular fracture, leading to fewer, larger fragments.

A microstructure prediction model was established by considering the volume fractions and grain size of α and β phases varying with process variables, and grain growth.
In two-phase (α+β) field, the microstructure change is mainly indicated as the change of volume fraction and grain size of α and β phases.
The model for predicting the microstructure evolution was expressed by volume fraction and grain size of α and β phases.
To predict the volume fraction and grain size of primary α phase, the geometrical model for grain size change of α phase developed by previous work [6-7] was used.
Assuming that the total number of α grains are constant, the grain size of α phase (d) can be calculated by the following equation. )(3/1)0/(0 mffdd µαα= (1) Where, d0 and fα0 are the initial grain size and volume fraction of primary α phase, respectively, and fα is the present volume fraction of primary α phase.

The increase of protein content in brown rice was neither proportion nor synchronization; The axis of japonica rice grain was nearly at the center and close to the ventral part of the grain fracture observed by confocal laser scanning microscopy, which was associated with the distribution of vascular bundles transporting nutrition to the grain.
Introduction Rice is the most important cereal crop with about 40% of total grain production in China.
The axis of rice grain was nearly at the center and close to the ventral part of the grain fracture, maybe because the major vascular bundle transporting nutrition to the grain exactly located in the back of the rice grain, and the major one then branched a number of minor vascular bundles surrounding the kernel, which allowed the cells near the back of grain to obtain more nutrition, grew faster and bigger, consequently, axis formed near the ventral part of the grain.
Axis of rice grain was nearly at the center and close to the ventral part of the grain fracture.
Moreover, we found the increase of protein content in brown rice was neither proportion nor synchronization, and the axis of japonica rice grain was nearly at the center and close to the ventral part of the grain fracture.

It can be seen in Fig. 1 that the melt spinning causes the major diffraction peaks of the alloys obviously broadened, which is ascribed to the refined grain and the stored stress in the grains generated from the melt spinning.
Fig. 4 Evolution of the capacity retaining rates (Rn) of the as-spun alloys with the cycle number: (a) 5 m/s, (b) 15 m/s Fig. 5 Evolution of the capacity retaining rate (R100) of the as-spun alloys with Zr content The evolution of the capacity retaining rates (Rn) of the as-spun alloys with the cycle number is described in Fig. 4.
The evolution of the capacity retaining rates (Rn) of the as-cast and spun Zr0 and Zr0.1 alloys with cycle number is demonstrated in Fig. 6.
The increased cycle stability Fig. 7 Evolution of the capacity retaining rate (R100) of the alloys with spinning rate Fig. 6 Evolution of the capacity retaining rates (Rn) of the as-cast and spun alloys with cycle number: (a) Zr0, (b) Zr0.1 of the as-cast alloys originated from substituting La with Zr is basically attribute to the refined grains resulted from such substitution.
The anti-pulverization capability of the alloy basically depends on its grain size.