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In the grain interior, the majority of slip is generally concentrated on a limited number of active slip systems for most grain orientations.
The relative volume of the grain boundary region is a function of grain size as well as the deformation conditions [5-7].
This results in a critical grain size, below which the grain boundary region extends over the entire grain and the enclosed cell/subgrain structure dominates the substructure development [5-7].
The formation of DRX grains involves simultaneous grain boundary movement as straining proceeds.
DRX grain size; Fig. 4).

With the development of nanotechnologies, the number of industrial processes dealing with the production of nanostructures or nano-objects is in constant progress (microelectronics, metallurgy…).
Especially, today’s materials can be both composed of nano-objects as clusters or decorated defects…, and contain a large number of interfaces as in nanometer-thick film stacking and buried nano-wires or nano-islands.
If we consider that not all the grains are growing, the fraction of growing grains fgr can be a fourth parameter.
The B solubilities in grains and grain boundaries were chosen to be the same, as well as the initial profiles (solid line) in grains and grain boundaries.
Grain boundaries.

The bending strength of brazed segments without CBN grains is 128MPa, a little higher than that with CBN grains concentration 75% 116MPa.
All the single-crystal grains fractured along the cleavage plane。
Compared with the fracture surface morphology shown in Fig.4, it’s easy to find that the number of fractured CBN grains decreases with the increasing of graphite content.
It implies that the bonding strength inside of copper-tin alloy and between grains and copper-tin alloy are both higher than the grains’ own strength with a low graphite content, so that the poor bonding and fracture happened through the CBN grains.
Moreover, micro-crack on the surface of CBN grains may exist because of the residual stress on the interface of grain and filler.

Fig. 1(a) shows the total number of dislocation lines with a simplified distribution to calculate the average space of a dislocation array.
Number of dislocation lines in a dislocation cellblock.
The total number of dislocation lines is proportional to the inverse of the average space of a dislocation array, once the applied stress exceeds the friction stress .
From equation (4), the number N of dislocation lines concentrated in a single dislocation cellblock is calculated to be 5929.
It has been formularized that the total number of dislocation lines within a dislocation cellblock is a material constant, and both sizes of dislocation cell blocks and the ferrite grains just after phase transformation are inversely proportional to the square root of dislocation density.

A phase mixture model is employed to describe the deformation behaviour of ultra fine grained materials (down to the nanometer grain size scale).
Equation (5) describes a viscous Newtonian flow law, where a generalised viscosity depends on the grain size and the grain boundary selfdiffusion coefficient.
With higher number of ECAP passes the fraction of high angle grain boundaries increases.
TEM investigation of the 16 pass specimen revealed non-equilibrium grain boundaries combined with equiaxed grains.
It can be conjectured that an enhanced grain boundary sliding as well as grain rotation may occur during deformation of such materials leading to increased ductility.

Yu et al. [11] proposed a fine-grained data access control scheme.
The children of a node x are numbered from 1 to numx.
The function index(z) returns such a number associated with the child node z.
Waters: Attribute-Based Encryption for Fine-Grained Access Control of Encrypted Data.
Lou: Achieving Secure, Scalable, and Fine-grained Data Access Control in Cloud Computing.

GSHP exhibited a better control in temperature in warehouse and grain heap.
The parameters of biological activity of grain were determined.
Currently, large warehouse is widely used in grain depot of China.
But due to its poor thermal insulation performance, the highest temperature in warehouse and grain heap can be as high as 30-35°C in summer, which results in serious breeding of a large number of pests and bacterial, which can affect the eating quality of rice seriously [2].
The total number of microorganisms The total number of microorganisms was determined by plate culture counting method [9].

After hot-band annealing at 850°C for 1h, grains coarsened dramatically.
It can make grains coarse and uniform in hot rolled strips, reduce the number of grain boundaries, aggregate and coarsen precipitates.
And it decreases (111) grains which nucleate along grain boundaries easily, while increases (100) and (110) grains, thus improves magnetic properties of electrical steel[1,2].
It's obvious that deformed grains in hot-rolled bands have recrystallized completely and the grain size of normalized samples is bigger than that of untreated ones.
Hence, grains coarse obviously.

The discontinuous electron density difference of phase interface Fe4N/a-Fe under the first order approximation results in the remarkable strengthening effect as well as the significant decrease in toughness and ductility, demonstrating the reason that nitrogen can cause cold shortness; as the electron density difference on AlN/γ-Fe, AlN/γ-Fe-C(Al) phase interface is very large and the continuous number of the phase interface is very small, the add of Al can hinder the growth of grain, as a result, the austenite grain is significantly refined and the removal of cold shortness caused by Fe4N can be achieved.
The Fe4N phase behaving as dispersion degree can distribute along grain boundary and prevent the movement of dislocation, resulting in the embrittlement of alloy.
The precipitation of AlN not only make the austenite grain refined, but also cause the decreasing in the content of free nitrogen in steel.
The covalent bond distribution on the (111) crystal plane of Fe4N (shown in Fig.1) is as follows: Fig.1 Atom arrangement on (111) crystal plane of Fe4N aN N Fec Fef , IB=1.5×2×2=6; , IC=1.5×4×1=6; The total covalent electron number of (111) crystal plane in Fe4N is.
If it is considered that the growth of recrystallization grain is connected to the continuity in interface electron density, the worse the continuity of phase interface, the more difficulty in the movement of phase interface, and the more difficulty in the growth of grain.

An alternative approach, based on recent advancements in XRD micro-focusing has enabled a limited number of XRD synchrotron facilities to quantify elastic strains in individual grains using the analysis of Laue diffraction patterns [4].
A large number of interrelated effects need to be considered when optimising the milling setup.
The gradient of this plot is used to quantify strain relief as a function of image number.
We observe, however, that the fitting Fig. 4 a) Full strain relief against grain number in directions parallel and perpendicular to the grinding direction for both the stepwise and continuous milling process. b) Full strain relief against core diameter size in grain 4.
Exceptions were grains numbered 3, 5 and 9 which demonstrated negative strain relief sign, and thus a tensile residual stress.