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The better ferroelectric properties of Ca0.4Sr0.6Bi4Ti4O15 thin film originate from the relatively high concentration of a-axis oriented grains.
And the average grain size of the thin films increases in the rough as x varying from 0 to 0.6.
It has been reported that for bismuth-layered perovskite films the rod-like grains are presented in (119) preferentially oriented films, while the ball-like grains may corresponded to the a-axis preferred orientation and the plate-like grains are c-axis preferred orientation [9-11].
As shown in Fig. 2, the number of crystallites in ball-like shape approximately increases firstly (0≤x ≤ 0.6) then decreases (0.6As x sequentially increasing from 0.6 to 1.0, the number of rod-like and plate-like grains of films increases while the number of ball-like grains cuts down, this is corresponding to the XRD results of Fig. 1.

The scanning electron microscopy (SEM) experimental results indicated that: under the force, non-crystalline materials distorted, crystal faces were torn along grain boundaries and crystal grains were disrupted.
So crystal size became smaller, more grain boundaries and more voids were formed, which supplied more free space for the movement of crystal grains and chain segments.
Introduction Ultra-high molecular weight polyethylene (UHMWPE) is a linear polymer with number average molecular weight in the range from one to ten million.
So crystal size became smaller, more grain boundaries and more voids were formed, which supplied more free space for the movement of chain segments and crystal grains.
So crystal size became smaller, more grain boundaries and more voids were formed, which supplied more free space for the movement of crystal grains and chain segments.

In the polycrystalline material (metal, alloy) the main microstructural parameter is grain boundary – i.e. surface interface between individual grains.
In an undeformed state, the structure is isotropic, the grains have isometric dimension and grain boundaries are not oriented.
In case of plastic deformation of this isotropic structure the grains will take anisometric dimension and grain boundaries are oriented, as seen in Fig. 2.
From the relative number (number to unit of length) of parallel test lines intersections with grain boundaries (PL)P and perpendicular lines ones (PL)O was total relative surface area (SV)TOT of grains estimated according to Eq. 1.
Planar oriented part of relative surface area (SV)OR of grains was estimated according to Eq. 2.

The structure of silicon grains is elongated relative to the growth direction, the dislocation density in grains is of about (5÷8) ×10 4 cm-2, the average lifetime of minority carriers is 4÷6 µs.
This results in a rather bad quality of poly-Si layers, namely in small grain size and large concentration of grain boundaries with a high concentration of dislocations acting as fast recombination centers for photo-generated electrons and holes.
Apart from using the carbon net as a substrate, we propose a number of new technical solutions to improve the crystal structure and photovoltaic quality of produced composite semiconductor material in this work.
X-rays investigations show that the main orientation of the grain surfaces are (100), (111) and (211).
We suppose that it is mainly limited by the presence of transition metal impurities collected by dislocations in grains and in grain boundaries [5,6].

The sizes of the grains within the recrystallization organizations were gradually diminished as the cold rolling reduction increased.
Fig. 1 Optical micrographs of annealed samples of Ti+P-IF steel in cross cold rolled reductions Due to the perpendicular between the directions of cold rolling and hot rolling, the part cold deformation can be used to offset the original grain boundaries and dislocations, reduce the stored deformation energy so as to reduce driving force of the grain nucleation and growth, therefore, the grain size of recrystallization and annealing become smaller.
Fig.2 is TEM morphology of samples of Ti+P-IF steel in different cross cold rolled reductions, it shows that with the increase of the deformation, the organization significantly enhanced. 30% down, appear grain size in the crystal and dislocation density is low, there are a lot of second phase particle distribution among grain boundary. 50% down rate, grain size of the crystals grow in quantity, dislocation density increases;the inhomogeneity of deformation cell increased, grain boundary more twists and turns; there are a lot of second phase particle distribution among grain boundary. 70% down rate, grain refinement is obvious, the difference between the crystal orientation increases, the deformation inhomogeneity enhance. 90% down rate, grain refining it, there is a large number of irregular shape of the second phase particle distribution are gathered.
With the increasing cross cold rolling reduction, the second phase particles after annealing were mainly separated along the grain boundary, and then grew up or made an arrangement in directivity through the removing of the grain boundary.
These grains after annealing distributed in cluster ultimately.

According to [10-13] the optimal values aopt, mopt, hopt are determined by the equation: aopt = 2.1×(1+nSdS/dCS)3–1.1; (1) mopt = 2.1×(1+nCdC/dS)3–1.1; (2) hopt = 2.1×(1+dH/dC)3–1.1, (3) where dCS, dS and dC are average grain sizes of coarse and fine aggregate and cement particles, respectively, mm or μm; nS, nC are the number of densely packed rows of grains of fine aggregate and cement particles, respectively, between grains of coarse and fine aggregate; dH is the width of the densest layer of cement hydration products between clinker insoluble particles, μm.
Let us suppose that the densest structure of the hydration product layer between clinker insoluble parts with the maximum number of electro- heterogeneous contacts s contacts consists of two rows of ettringite crystals, grown towards each other on the surfaces of cement particles or aggregate grains (Fig. 2, d), dG in (3) can be taken as 2×0.5 = 1 μm.
а) b) Fig. 4 Study into crack resistance of concrete under dynamic effects: the test sample of the rail base mounted in the testing machine MUP-50 The vertical loading on a rail had a frequency of 8 Hz, a force range of 100-235 kN, and the total number of cycles was 1.5 million.
A value of m specified corresponded to a width of the cement stone layer between fine aggregate grains of 20 μm according to equation (5).
The actual coefficient of grain separation of coarse and fine aggregate, and water-to-cement ratio to the optimal values aopt = 1.30, mopt = 1.27, W/Copt = 0.23, respectively, and a width of the cement stone layer between grains of fine aggregate 20 μm in C40/50 concrete provided the maximum values of physical and mechanical properties of concrete.

Besides, V2O5 addition changed its grain size distribution and resulted in some larger grains.
When the addition of V2O5 increased, the ratio of large grain rose and the distribution of grain size became broader.
Apparently both V and Zr elements were uniformly distributed inside the grains and grain boundaries without evidence of segregating.
This agrees well with the result that more number of larger grains were observed as listed in table 1.
(2) V2O5 with a low melting point can increase the number of large grains.

It can be seen that the bSn grain structure in Sn-0.7Cu-0.05Ni contains multiple bSn grain orientations (colours in the Euler angle map of Figure 3(b)).
It can be seen that the bSn grains grow in a columnar mode from the Cu6Sn5 reaction layer and there are more bSn grains near the layer and a decreasing number of grains further away from the layer, which is indicative of grain selection by competitive growth from the nucleation site.
(c) bSn pole figures where colours give the orientation of the grains in (b).
Note that the grain structure is quite different in the Sn-0.7Cu-0.05Ni / Cu joint in Figure 4 and Sn-3Ag-0.5Cu / Cu joint in Figure 6 where multiple columnar grains grew in Figure 4 and two mutually-twinned grains grew in Figure 6.
A synchrotron imaging technique has been used to detect the nucleation and growth of primary Cu6Sn5 and EBSD has been applied to understand the differences in number of tin nucleation events and grain structures between the two solders.

Evaluation of the Tensile Modulus of Elasticity in Parallel Direction to the Grain for Eucalyptus grandis Wood Specie André L.
Were used twelve specimens of Eucalyptus grandis wood species, tested in tensile parallel to the grain according to the assumptions of the Brazilian standard ABNT NBR 7190:1997.
Thus, by electing a finite number of forces and displacements results from the experiments, the modulus of elasticity of this methodology will adjust this set of unique way, resulting in more reliable modules since the number of sampling points increases.
Results and Discussion Table 1 shows the results of the tensile modulus of elasticity (MPa) n parallel direction to the grain of Eucalyptus grandis wood specie, with the sample mean (), SD the standard deviation and Cv the variation coefficient.
The results of the P-value of the Student-Newman-Keuls test was equal to 0.5618, revealing that no significant differences between the tensile modulus of elasticity in parallel direction to the grain obtained in both forms of calculation (P-value> 0.05 ).

As the ratio of the average diameter of fine grains to that of coarse grains is increased, the yield strength of the bimodal structure is decreased.
These properties come from different deformation behavior of fine and coarse grains.
The FE polycrystal plasticity analyses were made on several bimodal structure models which have different volume ratios of coarse to fine grain size dc/df and different volume fractions of coarse grains Vc.
The equivalent stress in the bimodal structure tends to be concentrated in the fine grains near the coarse grains but the number of grains where the stress is high is decreased.
These results imply that the coarse grains in the bimodal structure may relax the stress and strain in the fine grains and thus bring about higher yield strength and relatively higher ductility of the bimodal structure.