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Introduction The triple junction of grains is a linear defect, along which three variously oriented grains or three grain boundary surfaces are conjugated.
The grain boundaries are denoted by the bright dashed lines.
The grain boundaries are marked by thick gray lines.
As a result of rapid cooling, a large number of defects formed in the calculation block in addition to the grain boundaries: pores, vacancies, dislocations, disclinations.
The reason for the formation in polycrystals a large number of the strained triple junctions having a relatively "loose" structure with a high share of the free volume was elucidated in the study of crystallization in the three-dimensional molecular dynamics model.

Grain boundary sliding.
Figure 1.h shows the grain boundary offsets that occur in grains orientated at an angle offset to the tensile direction, with the early start of accommodation by surface grain separation or grain emergence.
This was observed across a number of grids, as well as at various locations on the surface that had not been FIB milled.
Again, this was exhibited across a number of grids, and in surface areas not FIB milled.
The number and size of these defects were believed to vary with strain-rate.

Fig. 3 shows the corresponding morphology of austenite grains.
When the strain increases to 0.3, which corresponds to the peak stress, many dynamic recrystallization grains occur at the prior grain boundaries with zigzag shape, which refine the austenite grain size.
When the interruption time increases to 10 s, quite a number of newly formed austenite grains appear around the prior grain although some grains seem to be nucleated just at the quenching time.
With increasing the holding time, the newly formed austenite grains grow inside the prior grains and impinged each other, which leads to relatively small and homogeneous grain size (Fig. 5c).
Average grain size after held for 50 s is about 28μm, which is much smaller than the prior grain size.

The Research on the Adaptation of Grain Production in China to Climate Changes Based on Structural Equation Model Jiliang Xue School of Economy and Management, Inner Mongolia University, Huhhot Inner Mongolia 010021 Email: xuejiliang1981@163.com Keywords: The Structural Equation Model; Grain Production; Climate Changes; MIMIC Model Abstract: This paper uses the year data from 1998 to 2009, according to the MIMIC model in structure equation model to construct the adaptability system model of China's climate change to grain production, and makes an empirical research, found that sows area, the consumption of chemical fertilizers, agricultural water conservancy construction expenditure and the rainfall affects the maximum on grain production yield fluctuation of our country ; then according to the estimation results calculated the latent variable intensity fluctuation of grain yield, found that the grain production fluctuation of output intensity in future is further toward the positive
The advantage of structural equation model could use a number of observable variables to score the unobserved variables.
The sowing area and consumption of chemical fertilizer affect the production fluctuation of grain yield in China from two aspects of the total grain yield and the yield per unit.
From the graph 1, we see the grain yield fluctuation from year 1998 is relatively acuteness in the years 1998-2009.
With 2004 as a dividing line, after it the grain yield fluctuation intensity in China tends to decline.

The average length of a crack is seen to increase at a lower boron concentration at grain boundaries, but appears less sensitive to the concentration of boron at grain boundaries as the boron concentration at grain boundaries increases(Fig. 5).
Dependence of average crack length (a) and average number of cracks (b) per weldment section on the calculated boron segregation concentration [8] Fig. 5 Variation of average length of single crack with the calculated boron content at grain boundaries with Eqs.(1) and (2) [8] .
When the solute concentration at the grain boundary induced by the diffusion of complex is higher than the equilibrium grain boundary concentration, a reverse diffusion of solute atoms from grain boundaries to the center of the grain will also occur along the gradient of solute concentration.
The experiments of P grain boundary segregation in INCONEL 718 alloy.
McLean grain boundaries in Metals, Oxford Univ.

In the low angle grain boundary with a tilt angle (2θ) of 2.1o consisted of the periodic dislocations array, the interval of those dislocations could be explained by the dislocation model for grain boundary.
Since the ultrafine grained materials have numerous number of the grain boundaries, it can be easily predicted that those mechanical properties must be governed by their grain boundaries.
The mean lamellar spacing of the grains elongated to RD is approximately 200nm.
In the ARB processed specimen, two types of grain boundaries are observed.
They called this a kind of non-equilibrium grain boundary.

Results shows, the stress-induced anisotropy of coarse-grained soil occurs under the interaction of internal irregular microscopic structure and external non-isotropic stress.
Introduction Anisotropy is one of the basic mechanical properties of the soil, especially for non-continuous material such coarse-grained soil.
There have been many achievements about coarse-grained soil anisotropy.
For sample D, since it experienced initial non-isotropic stress state, the number of long axis orientation in the interval of (-900,-600) and (600,900) obviously decreases，the number of long axis orientation in the interval of (-600,-300) and (300,600) also decrease，but the number of long axis orientation in the interval of (00,300) and (-300,00) obviously increases, clump long axis orientation changes obviously.
(3) stress-induced anisotropy of coarse-grained soil will occur under the interaction of internal irregular microscopic structure and external non-isotropic stress.

Growth of individual austenite grains measured with 3DXRD microscopy V.I.
The chemical compositions of the studied alloys, in wt.%, are (numbers in brackets are for C35 alloy): 0.21(0.36) C; 0.513(0.65) Mn; 0.2(0.3) Si; 0.086(0.23) Cu; 0.021(0.177) Cr; 0.049(0.092) Ni; less than 0.01 Mo, Sn, P, S.
By slightly rotating the sample around an axis perpendicular to the beam over an angle of 0.5º, a number of grains give rise to diffraction spots on a 2D-detector.
Growth type two is attributed to the nucleation and growth of new grains on the F-F grain boundaries (see Fig. 2b).
It was shown earlier [5] that at the very early stages of the transformation the formation of austenite on the F-F grain boundaries (at quadruple points, grain edges and grain boundaries) can take place.

Packing density and coordination numbers of the grains in the sintered powder are analysed with application of computer simulation.
The parameters, most widely used in the description of the packing types, are: i. packing density defined as the ratio of volume of solids to the total volume of solid grains and voids; ii. the coordination number distribution which defines the coordination numbers appearing with various probabilities.
The program allows simulating the grain packing and related coordination-number distribution as well as a dependence between the both.
To eliminate the border effects the students make a series of calculations of the packing density (ρ) for various grain radii (R) and then draw the results in the ρ vs. �-1/3 scale (where N is a number of the grains in the given volume).
The screen of the results contains information about total number of the spheres in a given volume, packing density and the coordination number distribution (Fig. 3).

We developed a multilayer system formed by introducing a number of thin silicon oxide layers into the polycrystalline silicon layer.
The number, and the thickness, of the buried silicon oxide layers determine the gettering properties of the multilayer structure.
If the number of buried oxide layers is low then the thickness of the single polycrystalline silicon layers is significantly greater than the lateral grain size.
In order to optimize the thickness and number of the buried oxide layers we prepared a number of structures.
The number of buried oxide layers was varied from 3 to 9.