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The von Mises equivalent stress, σ, and equivalent strain, ε, were calculated using the relationships [3]: )'n'm3( 3R2 M3 ++ π =σ (1) L3 RN2 π =ε (2) where N is the number of revolutions, M is the torque, m' (strain rate sensitivity coefficient) at constant strain is Nlog/Mlog &∂∂ , and n'(strain hardening coefficient) at constant strain rate is Nlog/Mlog ∂∂ .
As a matter of fact, the authors demonstrated that the Zn and Al contents were 2 and 1% respectively in grain interior, while the same elements were present in higher concentrations (5 and 3%) in the grain boundary zones, where all the Ca segregated during high temperature exposure.
In the light of the alloying elements segregation, even a mere addition of 0.3% Ca, as long as these dishomogeneities persist, results in a substantially higher local concentration in the grain boundary zones.
A recent paper [5] clearly suggested that this kind of microstructure should be modelled as a composite, composed by soft (the grain interior) and hard (the grain boundary region) zones, each characterized by a different value of the threshold stress.
In both cases the alloys were extruded, and as a consequence exhibited a recrystallized microstructure composed by equiaxed grains.

The grain size of the as-cast alloy is about 200~250µm, as shown in Fig.1a.
Work hardening usually caused by large number of pinned dislocations, which were resulted from the increasing dislocations density under external force.
It reveals that almost all of the grains were obviously elongated in the perpendicular direction to the compression axis.
The microstructure consists of unrecrystallized grain structure in the temperature range from 460~500 ℃.
At the higher temperature of 520 ℃, the elongated deformed grains are still dominant, and small amount of recrystallized grains distribute along deformation grain boundaries.

The mechanism of this shear instability is suggested to be the grain boundary slipping of previously fragmented grains.
This result is consistent with the experimental results obtained on polycrystalline materials where a number of grains with a variety of orientations have been observed [3].
As shown by EBSD, 15-20 mm thickness fragmented layer consisting of 5-6 mm grains has been generated below the worn surface after the sliding test.
It is known that the sliding–induced tribological layers are often composed of nanosized grains [1, 3], however, our EBSD equipment is not capable of detecting the grains that are so small.
Orientation Dependence of High-Angle Grain Boundary Formation during Sliding Wear in Copper Single Crystal, J.

The number of particles that migrate to the sintering neck increases under the same temperature conditions, and the ability to eliminate stomata between particles in the body is improved.
The densification process can be promoted by adding a sintering aid that can suppress the abnormal grain growth.
In transgranular fracture, cracks extend through the interior of the grain.
Intergranular fracture is defined as material fracture that propagates along grain boundaries and occurs when the grain ruptures along the fracture.
When the metal or alloy precipitates continuously or a discontinuous reticular brittle phase occurs along the grain boundaries, mesh-like brittle phases will directly bear the load under external force and will easily crumble to form cracks that expand along the grain boundaries.

The highly c-axis orientation grains on the surface of the sol-gel grown buffer layers [14] act as nuclei centers for the growth of the over-layered ZnO film deposited by sol-gel method.
The estimated values of grain size were found to increase from 44.3 to 51.4nm without and with ZnO buffer layers, respectively.
It can be attributed to the coalescences of grains[15].The relation between the parameter of crystal grain and with or without buffer layers is shown in Table 1.
Table 1 The relation between the parameter of crystal grains and presence/absence of buffer layers The thickness of the ZnO layer was 410~450nm approximately measured by Spectroscopic Number of sample FWHM Height of peak Size of crystal grain [nm] A 0.190 54286 51.4 B 0.213 32936 44.3 20 30 40 50 60 70 0 5000 10000 15000 20000 25000 intensity 2-theta 002 002 have the buffer A haven't the buffer B Fig. 1 XRD patterns of ZnO thin films with and without pure ZnO buffer layers prepared at 1073K Ellipsometry.
Moreover, there are some pores at the boundaries between the grain and substrate of the film without buffer layer(Fig.2 B).

Low activation energy of crystallization, however, is in favour of the relaxation process, the division of the amorphous phase or the process of diffusion in the amorphous matrix or on grain boundaries of the nickel microcrystallites.
The third stage, above the temperature of 300°C, is associated with the processes already taking place in the crystalline state, such as the transformation of the metastable nickel phosphides into stable phosphides and the grain growth.
The activation energy of the nickel net diffusion is 283 kJ/mol [1], while the corresponding activation energy of the diffusion on grain boundaries is 111.9 kJ/mol [2].
This diphase system is consisted of nickel crystallites (identification card number: 4-0850) and nickel phosphide crystallites (identification card number: 17-225) of the type Ni5P2 (Figs. 1-3).
Transformations proceeding in the structure of the Ni-P coating heated at 500°C are connected with processes proceeding already in a crystalline state (further creation of stable nickel phosphides and growth of grains).

The alloy without Pr shows a coarse grain structure, whereas that the total substitution of La with Pr reveals a fine grain structure.
It can be seen that this substitution resulted in a marked change in the grain structure of the cast alloys.
Discharge capacity of La0.7-xPrxMg0.3Al0.3Mn0.4Co0.5Ni3.8 as-cast alloy electrodes vs. cycle number.
Self-discharge rate of La0,7Mg0,3Al0,3Mn0,4Co0,5Ni3,8 alloy electrode vs. cycle number.
Soon after the hydride stability diminished considerably reaching the SDR value of approximately 27% in the cycle number 183 or after 49 days of cycling.

The elasto-plastic deformation model [12] was used for predictions, in which the explicit grain-matrix interaction [13] was adopted: (2) where and are stress and plastic strain rates of a grain and and are analogous variables for the sample, G is shear modulus and a is elasto-plastic accommodation parameter [13].
This shows that different types of grain-matrix interactions occur in both metals during deformation (strong interaction if ferrite and weak interaction in austenite).
Hence, we can conclude that grains with orientations belonging to texture maxima deform in a more homogeneous way (with respect to a neighboring material) and, consequently, they have lower values of the second order residual stress.
The stress relaxation, which is thermally activated, depends on the stacking fault energy and number of available slip systems.
The work was financed by the Polish National Centre for Science (NCN) basing on decision number: DEC-2011/01/B/ST8/07394.

The average grain size was 0.6µm.
Although a specimen contains a large number of embryos, the least stable embryo becomes critical and nucleates when the specimen is continuously cooled below T0.
On the other hand, small specimens have a small number of embryos and thus the statistical variance of the least stable embryos becomes large.
In practice, a large number of embryos with different nucleation temperature T were generated for the distribution function of n=1, 2, and 3, using Eq. 1 by substituting random numbers between 0 and 1 for x, max /1 )1( TxT n −=
This density corresponds to the population of 1 embryo per 10 6 grains of 0.6µm size.

Based on the object that the resources and energy must be efficiently used in the process of China’s urbanization, we select the following five typical indicators to comprehensively evaluate the energy consumption efficiency of a county, including the total number of employees, total investment in fixed assets, sown area of grain crops, total energy consumption, gross domestic products.
Supposed that there are regions, and the vector ( ) is the value of total number of employees, total investment in fixed assets, sown area of grain crops, total energy consumption, gross domestic products in the region j in the year.
As shown in Fig.2, based on the average value, the scale of various indicators which Chifeng needs to make improvement has continuously expanded, such as the employment rate, total investment in fixed assets, the rate of grain production, and energy consumption.
On the aspect of grain production, the efficiency of farmland has been lower, the energy output efficiency has also been continuously falling, Especially from 2010 to 2012, the scale of these two indicators which need to improve has been larger.
Moreover, a certain insufficient output also exists in the total investment in fixed assets, while the output efficiency of grain production and employment gradually tend to be reasonable.