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The number of guide trough is 6 to 10.
Condition of soybean accumulation: After observing in the warehouse, the number of cumulate grain piles in the squat silo is six, the distribution of grain piles is shown in Fig. 5.
By observation, we can know that the first grain pile is maximum, the next is the fifth grain pile, and the sixth grain pile is smaller than the fifth grain pile, but it relatively larger than the second, third and forth grain pile.
The main reason of the middle heap largest: The number of original design for branches are ten but the test use five branches at present.
That is to say, the blanking in the middle from one point finally become multi-point, grain and impurity can distribute in a number of grain piles.

Nowadays, the main manufacturing method for most magnesium components is still die casting, because most magnesium alloys have a limited number of slip systems related to the HCP crystal structure, resulting in poor processing capabilities [1].
A large number of DRX grains appeared around the grain boundary.
A large number dislocations generated inside the grains during the deformation process.
The intergranular LPSO and fine a-Mg grains located at the boundaries of the coarsely deformed grains.
The nucleation of DRX-ed grains at the kink bands and a-Mg grain boundary may be achieved by forming sub-grains and increasing their misorientation (i.e., CDRX mechanism).

Introduction Overwhelming majority of publications on SPS (experiencing exponential growth in numbers during the last decade - see Fig.1) describe empiric trial-and-error attempts to consolidate various powder material systems 1.
The developed model pursues the purpose of outlining a concept of a combined account of various material transport mechanisms in electric-current- assisted sintering, omitting a number of factors (such as spatial current density, temperature, porosity and grain size nonuniformities, different sources of grain growth, role of surface diffusion, phase transforma- tions, possible (still debatable) plasma formation, presence of surface oxides, etc).
Constitutive Model The flux of matter J r caused by the grain boundary diffusion is determined by Nernst-Einstein equation [1] including the chemical potential gradient along the grain boundaries due to the normal stresses and the electromigration: EC Cσ σ = +J E r r r ∇∇∇∇ (1) Here E r is the component of the electric field in the tangent plane of the grain boundary, σ∇ r is the gradient of stresses normal to the grain boundary, Cσ =δgbDgb/kT, where Dgb is the coefficient of the grain boundary diffusion, δgb is the grain boundary thickness, k is the Boltzman's constant, T is the absolute temperature.
Fortunately, the theory of electromigration is quite well-developed (however, never applied in models of sintering, as mentioned before), therefore the necessary model parameters and stress-strain assess- ments are readily available for a number of materials.
The calculations have been conducted for different grain sizes: (a) G=40µm, (b) G=1µm, (c) G=100nm.

With the increase of Fe-V, vanadium-rich carbides number increase, the grain size and hardness increase firstly then decrease above 2, at 20% gain the highest.
Vanadium has characteristics of improving solidification and refining the grain for improving crack resistance.
However, when Fe-V is very low, the grain size is thick and the direction of the columnar grain is remarkable, so the solidification cracks appear.
Effect of grain refinement is very obvious as increasing in Fe-V added content.
With the increase of Fe-V, the carbide phases number increase; the grain size and hardness increase firstly then decrease, at 20% gain the highest.

It can be seen the grain size of 1#, 2#, 3# are relatively small.
At the same time, Ti-Zr combined deoxidation process used in the production could form a large number of Ti-Zr composite fine particles which could pin austenite grain boundaries in the welding process to inhibit austenite growth, and to promote acicular ferrite nucleation during cooling [6].
Fig. 7 Three-dimensional reconstruction of acicular ferrite grains and a part of a big austenite grain, showing the partitioning of an austenite grain by acicular ferrite laths or plates [8] Effect of preheating on the toughness of CGHAZ.
The fine-grained mixed microstructure has very good impact toughness.
Wu, Effect of acicular ferrite formation on grain refinement in the coarse-grained region of heat-affected zone, Materials Characterization, no. 61, pp. 726-31, 2012

Mean grain diameters in samples cast in permanent mold (φ 80×50mm) were determined by line analysis.
Morphologies of inclusions, grain structures and Fe-rich phases are shown in Fig. 1 to Fig. 3.
After high-efficient melt-treatment, inclusions in the samples exist uniformly in the tiny flake/particle form, and their number is very few (Fig. 1 [c]), and grain appears in the fine equiaxed form (Fig. 2 [c]), and Fe-rich phases transform into tiny, sphere/short stick form (Fig. 3 [c]), EDAX analysis has shown that the phases are turned into complex (AlFeSiRE) compounds.
For Al piece prepared by high-efficient melt-treatment, the inclusions content and the number of micro-porosities are all reduced obviously, and the Fe-rich phases are changed into a favorable form, which decreases the number of microcrack sources resulting in the fracture of the material remarkably, thus making the mixed fracture fashion be transformed into the congregation of transgranular micro-hole.
Since the number of defects is very few, their mean distance is larger, thus increasing the resistant force of crack expansion.

However, if the number of stacking layers and/or the reduction per pass increases some advantages will be expected [3].
Ia increases with the number of passes, which means that the severity of the process also does.
Evolution of the average intensity Ia with the number of passes in the ARBed samples.
Equiaxed cells/(sub)grains with diameter smaller than 1 µm are seen.
However, the cell/(sub)grain size of the three deformed samples is very similar.

The integration must be able to support complex authorization specifications and the fine-grained resources access requirements that the various parties may have.
In this paper, we use a fine-grained policy based on RBAC in which roles are used to simplify authorization management and views are to control services and resources by fine grains.
In summary, the main advantages of the policy are fine-grained, reusable, type-checked specifications of access policies.
There are three kinds of constraints when a role is defined: Base number constraints; Leading role constraints; Mutual exclusion constraints.
Views also serve as basis elements for fine-grained access control policy.

ECAP at moderate-to-high strains leads to the formation of a bimodal grain structure with grain sizes of around 1 and 8 µm and volume fractions of 0.3 and 0.6, respectively.
Factors affecting grain refinement, as well as the mechanisms of deformation-induced grain formation in such materials, are currently being debated and are not clear.
Dark regions arrowed in (c) and (d) are composed of fine equiaxed grains with the grain size of around 1 µm.
The other is composed of relatively coarse grained regions with grains of around 8 µm, which maintain an essentially equiaxed shape after each ECAP pass.
It is known [4-7] that evolution of deformation bands can play a key role in the occurrence of grain refinement during IPS in some metallic materials; in other words, a gradual increase in the number and misorientation of these bands and their conversion into high-angle boundaries can result in the formation of a new grain structure through cDRX [4,6,7].

Through long distance migration of its high angle grain boundary after nucleation, the recrystallized grain usually grows to tens of micrometers.
Shih et al [32] and Torre et al [33] also observed similar softening phenomenon in yield strength in ECAP processing of Oxygen Free High Conductive (OFHC) copper. 0 4 8 12 16 20 24 2.5 3.0 3.5 4.0 4.5 5.0 5.5 99.98 wt% Cu ECAP at RT ECAP Load, T Number of ECAP Passes 0 4 8 12 16 20 24 0 90 180 270 360 450 0 10 20 30 40 50 60 Yield Strength 99.98 wt% Copper ECAP at R.T.
Tensile Yeild Strength, MPa Number of ECAP Passes Elongation, % Elongation Fig.1 Dependence of yield stress and elongation upon ECAP passes.
A relatively well-defined recovered grain was seen in figure 5(a), to the left of the triangular grain, well developed grain boundary with fringes was observed condensing out from grain boundary dislocations extending far into the interior of the neighboring grain (crystal fragment), as shown by the white arrows in the figure.
Figure 5(b) shows local (sub-) grain boundary migration that results in the diminishing of some small (sub-) grains or crystal fragments, and the increase of grain boundary misorientation, as indicated by the white arrows, where two triangular-shaped (sub-) grains with well defined grain boundary fringes on their all three boundaries was diminishing by the migration of their all three grain boundaries 0.1µm a b Fig. 5 Typical features of (sub) grain boundary activity observed in samples during ECAP observed.