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Using atomistic simulation technique to modeling the PMMA-b-PVP melts at meso-scale is still difficult nowadays because of the huge number degrees of freedom in the system.
A possible solution to this problem is to reduce the number of degrees of freedom through the mapping of an atomistic model onto coarse grained structures.
Fig. 1 Illustration of the coarse graining mapping schemes for (1) PMMA and (2) PVP.
Coarse-Grained Simulations 3.1.
The coarse-grained dynamic simulations are faster than atomistic ones.

However, very recent advances in the processing of theoretically-dense metals with submicrometer grain sizes have provided the opportunity to extend the understanding of flow behavior to include materials where the grains are exceptionally small.
Following ECAP, the mean linear intercept grain size was L = 0.3 µm corresponding to a spatial grain size of d = 1.74 × 0.3 ≈ 0.5 µm.
It is apparent from Fig. 1(b) that the maximum elongation occurs at a faster strain rate after pressing through 8 passes and this is due to the increasing fraction of high-angle grain boundaries with increasing numbers of passes in ECAP [15].
Both of these alloys were fabricated from high purity materials and the grain sizes prior to ECAP were ~200 µm in the Al-Mg-Sc alloy and an exceptionally coarse grain size of ~10 mm in the Al-Sc alloy.
Horita, in: Ultrafine Grained Materials IV, edited by Y.T.

Also, there was a moderate effect of initial grain size on the DRX grain size.
Since the number of triple junctions in this fine grain material is much higher than that of the coarse grain, a lot of new grains were formed at these sites and, therefore, the necklace structure was not as pronounced.
Increasing the strain beyond the peak (Fig. 6b) led to more new small grains on the pre-existing grain boundaries or within the grains.
Fig. 7 shows the dependency of DRX grain size on the initial grain size as a function of Z.
As is clear in Fig. 7, there is a dependency of DRX grain size to the initial grain size and this dependency increases with decreasing initial grain size.

This dissolution resulted in grain separation at the surfaces and finally in fracture.
And the dissolution was concentrated on those grains adjacent to pores rather than those in the dense region.
And the hydroxyapatite showed characteristic absorption bands with maxima at the wave numbers of 1095, 2043 and 568cm -1 which should be ascribed to the asymmetric stretching vibrations of P-O groups in the PO4 tetrahedron.
It was probably due to the absence of grain boundary secondary phase.
TEM results showed the secondary phase around the grain boundaries was significantly decreased.

However their poor ductility due to a small number of slip systems in the basal plane and a difficulty in dislocation activities in the non-basal plane limits further applications.
The SPD processed materials show not only the unique physical and mechanical properties inherent in various UFG materials but also a number of advantages over nanostructured materials manufactured by other methods through powder processing.
With increasing the ECAP processing temperature, the number of cracks decreased, because the activity of non-basal slip systems [4], hence the ductility of Mg, increases with increasing temperature.
The initial grain is equiaxed and larger than 1 mm, showing a recrystallized state with some twinning in the grain interior.
In addition, Mg alloys with fine grains of less than 10 µm (this is similar to our small grain size!)

Moreover, the cases of the as-received sheet with smaller grains had smoother surface textures than those of the annealed sheets with larger grains.
In a micro metal forming process, it may be only a small number of grains directly involved in deformation.
Experiments Grain Size.
The cases of the as-received sheet with smaller grains had smoother surface textures than those of the annealed sheets with larger grains.
Moreover, the cases of the as-received sheet with smaller grains had smoother surface textures than those of the annealed sheets with larger grains.

The application case proved that the proposed method can improve the feasibility of the program in grain production, and it is suitable for on-line grain production control for food system.
The grain production system is the gray original character systems influenced by multi-factor, and the major factors of affecting the grain production can therefore be established.
It makes the annual grain production（y） to the series of the system feature .
The results of quantitative analysis showed that the sequence of influencing factors and the behavior characters of the system have higher relevance.So grantee the number of input vector for six, the paper establishes the mapping relationship between the input vector and the output vector. represents embedding dimension.
By the above analysis, the model is a effective tool for grain production forecast.

Grain growth kinetics of accumulative roll bonded AZ61 alloy H.
Based on the experimental results of grain growth during annealing treatments, the grain growth exponent and the activation energy for grain growth were determined.
However, with limited number of slip systems and hexagonal close packed structure, magnesium alloys exhibit limited formability at ambient temperatures.
It shows ultrafine grains consisting mainly of α-Mg phase with an average grain size of 0.5 µm.
Wang, Grain growth kinetics of a fine-grained AZ31 magnesium alloy produced by hot rolling, J Alloys Compounds. 493 (2010) 87 – 90

Some methods for grain refining were reported [1,2].
After double repeated quenching, there were many coarse grains in steel A and B, but there was no coarse grain in steel C.
Grain refining mechanisms are as mentioned below.
Double R.Q. 1 10 Prior austenite grain diameter [µm] 50 5 * * *Many coarse grains were observed.
(3) An increase in Cr content resulted in the formation of a number of fine carbides in carburized layer of specimen during heating to repeated quenching after carburization.

The microstructure formed by severe plastic deformation is an unusual structure which can be hardly characterized only by the mean grain size especially after low number of ECAP passes.
The first, intersection count NL- the mean number of intersections between grain profile boundaries and unit lengths of random test lines.
The second, profile count NA - the mean number of grain profiles per unit area of the observation window.
An increase of the value of CVa on the microscopic level is influenced by higher number of fine grains present in the microstructure.
Thus, it is very difficult to determine quantitatively real grain size after low number of ECAP passes.