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Results and discussion 3.1 Crack Fig.5 Effect of RE ferrosilicon alloy addition amount on the crack rate Addition amount of RE ferrosilicon alloy(g) Crack rate (%) Tab 4 The crack number and crack rate in samples Sample Crack number Crack rate A 21 40% B 11 30% C 9 26% D 2 6.7% E 6 20% The statistical results of crack number and crack rate in the samples are given in Table 4.
Table 5 The content of elements of samples (wt%) Sample C Si Mn P S Al Cu Ce A 0.314 0.785 1.127 0.030 0.018 0.093 0.027 0.006 B 0.323 0.821 1.053 0.022 0.016 0.095 0.059 0.023 C 0.318 0.85 1.066 0.032 0.014 0.087 0.026 0.037 D 0.287 0.699 1.080 0.035 0.012 0.102 0.028 0.057 E 0.286 0.663 1.088 0.034 0.016 0.089 0.029 0.064 3.3 Microstructure of the samples in as-cast condition 1600μm Fig.7 Grains of casting sample A (a), B (b), C (c), D (d) and E (e) 1600μm (a) (d) 1600μm (e) (b) 1600μm 1600μm (c) The grains characteristics of microstructure of the casting samples are shown in Fig.7, where sample A, B and C show coarse-grained, while sample D and E exhibit greatly refined grains.
The reason is that the RE content in Sample A, B and C was lower than that in Sample D and E, which was not sufficient to refine grains.
Therefore, grain refinement has a positive function to reduce cracks.
At the same time, it can be seen that the grain size of sample E was larger than that of sample D because the excessive RE made grains coarsened again.

With nitrogen rate (168 kg/hm2), irrigation (90 mm) in jointing stage, and irrigation (70 mm) in heading stage, grain yield was higher.
Five factors were showed by capital letter (A, B, C, D and E) and four levels were showed by number in right hand of capital letter respectively.
It also showed that irrigation was main factor of improving and ensuring crop grain yield in arid region.
Therefore, the optimum combination of higher GY grain yield was A2C1D2.
Grain water use efficiency (GWUE) comprehensively reflected the relationship between water consumption and grain yield.

Rotation of grain crystal lattice is the basic mechanism of texture formation and of anisotropic behavior of metals during plastic deformation.
Also the intensity of grain-matrix interaction plays an important role in the prediction of the above quantities.
Besides the lattice rotation, also the intensity of grain-matrix interaction has a strong influence on the predicted results, therefore it was also studied.
The increment of displacement gradient of a grain resulting from a slip with δg shear is: (2) The plastic strain increment of a grain is the symmetric part of : (3) The rigid body rotation (plastic rotation) increment of a grain is the asymmetric part of : (4) Two definitions of crystal lattice rotation Classical definition (CL) Let us consider that total sample rotation, as well as a resulting rotation of each grain, is zero.
This work was financed by the Polish National Centre for Science (NCN) basing on the decision number: DEC-2011/01/B/ST8/07394.

It was found that the impact frequency represented by the number of balls from vials is an important parameter a milling process.
Average grain sizes evolutions with milling time in al type of milling condition are shown in fig. 6.
In the last stage of milling (between 8 and 16 h) the grain sizes is reduced from 35 nm to 22 nm.
It can be explained by number of balls which give the number of impacts and their velocity (higher in I than II and about the same in III and IV type of milling conditions).
This can be explained by higher number of ball – ball and ball – inner wall of vials impacts in case to use type I and III milling conditions (higher number of balls with 11 mm diameter).

Three microstructures such as a bimodal structure (B), a lamellar structure in small grains (Ls), and a lamellar structure in large grains (LL) were prepared.
LS (lamellar in small grains) 1000 (α + β) 1010 ˚C (α + β) / 3 h F.
LL (lamellar in large grains) 1080 (β) 1080 ˚C (β) / 3 h F.
In the Eq. 1, Lx and Ly represent the vertical or horizontal length of the SEM image, Nx and Ny represent the number of intersections with straight lines drawn vertically or horizontally, DSEM and DRe represent the scale bar length on SEM and actual images.
The decrease of stress exponent in the low applied stress level was found in B with grain size of 110 mm and LL with grain size of 550 mm, but it wat not found in LS with grain size of 90 mm.

Aiming at the defects of commonly used methods of gravel size design and the characteristic that the gravel used in field operation is actually a mixture of gravel with multiple grain diameters, this paper builds a model of pore structure in gravel layer through researching the gravel pack structure caused by the gravel of two grain diameters mixed under actual packing conditions, calculates and analyzes the pore sizes in gravel layer.
Ultimately, based on Saucier method, this paper presents a new gravel size optimization idea for gravel packing sand control with multiple grain diameters mixed, which agrees with the actual situation of industrial gravel, and gives the idea’s computing method.
Model Building and Analysis of the Precision of Sand Blocking To facilitate the analysis, it is assumed that the gravel used for packing consists of two kinds of gravel with two different diameters and the same density, the ratio of grain number is 1:1, and the distribution after packing is uniform and compact, the two dimensional drawing of its possible arrangement pattern is showed in Fig.1.
Through calculation we get the equations as follow: （1） Where, Dmax is the grain diameter of bigger gravel, Dmin is the grain diameter of smaller gravel, dA、dB、dC、dD are the equivalent diameters of four different arrangement patterns, d´ is the average grain diameter of formation sand, and there are always d´＞dD.
The SPE paper of number 8428 has mentioned that the uniformity of formation sand have important impact on the sand control effect of gravel packed well.

Effect of Increase of Dihedral Angle on Thermal Grain Boundary Grooving W.
Also, backscattering electron Kikuchi patterns for each grain adjacent to the groove in Fig. 4 changed across the groove root confirming the existence of a grain boundary below the groove root.
The number of spatial mesh points used in computation is 401 and the error tolerances in time integration are set to 10 -9.
During this period the grain boundary grows longer and the total surface area decreases.
The newly formed grain boundary is almost straight in the simulation.

Basic parameters of the wheel are granularity (the size of abrasive grains) and structure (percentage of an abrasive material in volume of the tool – quantity of abrasive grains).The process scheme at such task definition is submitted in fig. 1.
The location of abrasive grains in volume of the tool is described by the law of uniform distribution of a random variable [7]: , (2) where (x0i, y0i, z0i) – coordinates of the center of the abrasive grain number i, D – diameter of the tool, B – height of a grinding circle, H – thickness of a outer layer of the tool.
As the approximating figure of a form of abrasive grain the elliptic paraboloid of rotation is accepted:
(3) The quantity of grains which is located in volume of an outer layer of wheel is result from division of the volume occupied by all grains into the volume of mean single grain: , (4) where W – part of an abrasive material in the volume of tool, – granularity of a wheel.
Knowing coordinates of location of each grain in a wheel it is possible through a ratio of speeds of workpiece and the tool to calculate the coordinate of location of scratches on workpiece: , , (8) where i – number of abrasive grain, j – number of a turn of a wheel, k – number of scratch.

If the support stiffness of a single abrasive grain kg can be obtained, and the number of abrasive grains in contact approximated, a reasonable estimate of the contact stiffness can be obtained by the product of these values.
In this initial grinding situation, since the contact area between grinding wheel and workpiece is obtained from the geometric contact length lg and wheel width b, the number of abrasive grains in contact can be approximated by the product of the contact area and the number of abrasive grains per unit on wheel surface.
To calculate the number of abrasive grains in contact, a knowledge of the abrasive grain density per unit area on the wheel surface is needed.
The number of abrasive grains on the wheel surface can therefore be estimated by multiplying the number of cutting points by 1/2.
Consequently, in the grinding situation as shown in Figure 3(b), an initial contact stiffness of the grinding wheel K'con is obtained from the product of the number of abrasive grains in contact and the support stiffness of a single abrasive grain kg as follow

The average grain size of TiNi coatings ranges between 60 ÷ 160 nm.
The process of formation of coatings was carried out in a specially designed technology (patent number 2430191), by the technology described in the patent number 2354750 (Fig. 1).
On (Fig. 4k) shows the electron diffraction pattern of the alloy TiNi, alloy mainly composed of randomly disoriented nanoscale grains.
The distribution of grain size in the surface layer of TiNi and percentages is shown in Fig. 5a.
Between the grains of austenite structure located intermetallics particles Ti2Ni are located.