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Commodity grain is mainly from the cities and counties.
(2) Select the condensation point of the predetermined number, and the initial classification sample data
(2) The difference of the arable land and the number of the employed population The area of cultivated land is an important factor affecting the grain production capacity.
The first category is the grain production capacity in the worst area; the second category is the grain production capacity of the poor area; the third category is the grain production capacity of strong area; the fourth category is the grain production capacity of the strongest area
(2) Cluster analysis results show that the grain production capacity of Jilin Province with geographical location, number of each area, the area of cultivated land and agricultural population modernization level has great relevance.

%P) by refining grain size.
Microstructural evolution of the copper alloy with the number of the 3-layers ARB cycles was investigated by optical microscopy (OM), transmission electron microscopy (TEM), and electron back scatter diffraction (EBSD).
Results and Discussion Tensile properties of Cu-0.02P alloy (phosphorus deoxidized copper) as a function of number of 3-layers ARB cycles have been shown in Fig. 2.
Tensile strength of the specimen processed by the 2-layers and 3-layers ARB increased with the number of cycles.
A large number of dislocations and cell structures were observed in the samples after 3 cycles.

Grain boundaries energy can be selected by a unit and a number of the most adjacent unit micro orientation combined to define, it can be described as: (5) Where Si and Sj are the i-th unit and its adjacent unit j orientation, contribution J for the adjacent cells on the grain boundary, it is proportional to the grain boundary energy, is Kroneckerδ functions, when ,it can be referred , when , it can be referred , the driving force of grain boundary migration is the reduction of the grain boundary energy.
The migration speed is: (7) The simulation results The evolution of the microstructure of the grain growth process Fig. 1 shows microstructure evolution process of the grain growth process simulation, simulation maximum orientation number Q = 32 is taken, simulation hexagon side length sets to 100, the simulation steps sets to 1000,in the photo, Fig. 1 (a)–(d) Correspond to the simulation step number 0 MCS, 250 MCS, 750 MCS and 1000 MCS of grain image, as can be seen from the graph, with the simulation time increased, grain grown, the average grain size increase.
In the grain growth process, smaller grain has constantly been adjacent size larger grain annex, curve boundary constantly tend to linear, reflecting the basic trend of grain growth.
Fig. 4 shows the change of the grain growth process in grain energy, it can be seen by the graph, in the initial moments of high grain energy, along with the grain recrystallization and the process of grain devouring growing up, the energy is continuously reduced and tends to be stable, to 300 MCS, grain energy almost no longer decreases and reaches a constant value.
Fig. 3 The relationship between the average grain size and the number of MCS steps Fig. 4 The relationship between the grain energy and the number of MCS steps Conclusions With the increase of simulation time, the grain grow older, the average grain size increases, and into a discrete distribution, to a certain extent, it reaches the maximum grain size, and no longer changes, stabilized.

China nami_zhu@yahoo.cn Key words: lattice constant; cohesive energy; grain size; nanocrystallite Abstract.
Nm is the ion number in the fine crystallite with m layer ions out of origin ion.
Two limits are taken into account: ion distribution in a fine crystallite is close to spherical symmetric; the number of cation and the one of anion is approximately equal.
Thus, we can conclude that the lattice constant decreases with the reduction of the grain size for NaCl structure ionic crystallites.
For BCC structure metal crystallites, computed by the above method, obtained the dependence of rn and r1 on atom layer number m are shown in Fig.2(c) and 2(d).

The specimens of 3 and 4 passes ECAE have extremely fine-grained with 200-300 nm of the grain size.
The hardness of ECAE processed Al-3%Mg alloys increased with increasing the number of passes and finally reached up to 150 HV at 4 passes.
The relationships between the grain size, dislocation density and the number of passes of Al-3%Mg alloy were shown in Fig. 2.
The grain size decreased with increasing the number of passes until 2 passes.
On the other hand, the Figure 1 IPF maps of ECAE processed Al-3%Mg alloy dislocation density, of course the hardness, increased with increasing the number of passes beyond the microstructure was saturated.

Gerasimov1,b* 1Perm National Research Polytechnic University, 29, Komsomolsky ave., Perm, Russian Federation acrocinc@mail.ru, bromagrizly@gmail.com Keywords: molecular dynamics, crystallization, grain boundary, grain boundary analysis, grain boundary energy, EAM, central symmetry parameter.
Therefore, particle method is used to simulate the formation of grain boundaries.
Berendsen thermostat suppresses fluctuations of the kinetic energy, so the sample canonical ensemble will have the discrepancy which decreases as the (where N is the number of particles in the ensemble).
The average number of particles in the calculation region becomes equal to 170 000 (in the ideal crystal lattice of copper this number of copper must be equal to 177 000), which gives 96% of real copper density; in the considered central region this number is not more than 106 000.
Dependencies of the number of atoms of different types as a function of time were built.

FIRST-PRINCIPLES STUDIES ON GRAIN BOUNDARY ENERGIES OF [110] TILT GRAIN BOUNDARIES IN ALUMINUM Y.
It is important to accurately estimate the grain boundary energy in order to elucidate the atomic structure of the grain boundary.
Grain boundary energy.
The grain boundary energy is determined from the difference between the energy of a supercell containing the grain boundary and the energy of a supercell containing an equal number of atoms in the bulk environment, divided by the cross-section of the supercell.
Therefore, the grain boundary γ is given by SEE sg2 − =γ , (1) where Eg is the total energy of the supercell containing the grain boundary, Es is the total energy of an equal number of atoms in the bulk environment, and S is the cross-section of the supercell.

The rate-sensitivity exponent in the rate-type constitutive relation is closely related to the number of active slip systems.
Song and Abe [3] pointed out that, by using instruments such as laser-scanning microscope, r-value can be defined for respective grains in polycrystalline metal from the changes of grain profile or grain area during plastic deformation.
The relation between the shape of yield curves and the number of active slip systems was clarified.
The 12 slip systems in fcc crystal are numbered from k = 1 to 12.
It was shown [6,7] that, by changing the value of , the effects of the number of the active slip systems is studied.

This adds an additional factor of two to the number of symmetrically equivalent boundaries so that 2•2•122 symmetrically equivalent grain boundaries are generated from a single grain boundary trace.
Journal Title and Volume Number (to be inserted by the publisher) 3 Results Based on the EBSD data, the sample exhibited negligible grain orientation.
Journal Title and Volume Number (to be inserted by the publisher) 5 MRD Figure 3.
Boundaries that create a misorientation with the minimum number of dislocations are preferred and these are typically boundaries that are perpendicular to the Burgers vector of the dominant dislocation.
Acknowledgment This work was supported by the MRSEC Program of the National Science Foundation under award number DMR-0079996.

The total number of atoms was 5,103,926.
This is less than the number that would be present in a single crystal of this volume due to the lower density of atoms at the grain boundaries.
This provides a computationally efficient way to estimate the average grain size at a given time by simply counting the number of non-crystalline atoms.
The most obvious feature is that there are a significant number of twin boundaries in the system.
It is also observed that vacancies and a large number of twin boundaries are produced during the growth consistent with recent experimental observations.