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V=VAB{VAA+VBB}/2, with Vij pair interaction energies) and zl is the lateral coordination number (Z=2zv + zl).
According to the Stephan's law, constant means a linear interface shift, which was   1, 1, 1,     iiviiiviiI cztczJJ   czJ IIvI   1     Mcczzz vlvI      Vczzz vlvI  0 0.2 0.4 0.6 0.8 1 0 50 100 150 200 250 Number of layers Atomic fraction of A t=67t1 (b) 0 0.2 0.4 0.6 0.8 1 0 50 100 150 200 250 Number of layers Atomic fraction of A t=67t1 (b) 0 0.2 0.4 0.6 0.8 1 0 10 20 30 40 50 Number of layers Atomic fraction of A n(X=an nI n c t=t1 (a) 0 0.2 0.4 0.6 0.8 1 0 10 20 30 40 50 Number of layers Atomic fraction of A n(X=an nI n c t=t1 (a) experimentally confirmed during nanoscale dissolution of Ni into Cu single crystalline substrate [2].
This would have two advantages: i) it would provide numerical estimate for K (which is very rear in the literature (see e.g. [14]) and ii) the numbers obtained for D could be compared to the diffusion coefficients known from independent measurements.
Ni/Au system: In this system, due to the inaccuracy of the data (and to the complication related to the fast grain/boundary diffusion of Au along Ni grain-boundaries, which had to be separated from the first parts of the kinetic curves [4]) did not allow to estimate separately either K or cD.
It can seen that, although the experimental data show a relatively high scatter and thus the estimations gave numbers with about one order of magnitude uncertainty, the values of X'* are consistent with the observed kinetic exponents and also with the tracer diffusion data.

After 18 hr of mechanical alloying, fine grained microstructure was obtained and homogeneous distribution of all metal elements was achieved.
However, RHEAs synthesized through mechanical alloying and followed by conventional sintering and the oxidation happened and their effects in mechanical properties were reported in less numbers.
EDS analysis of Al25Ni25W25Cr20V5 RHEAs powders Fig. 4 (b) shows the lattice parameter value 3.2 Å and it was reduced to 2.85 Å due to grain size decreased with milling time.
Narayanasamy, Effect of coarse grain content on microstructure, cold workability and strain hardening behavior of trimodaled AA 6061 nanocomposites reinforced with multi-walled carbon nanotubes, Adv.

The experiment was initially carried out by adding a number of rare earth oxides (REO) to the garnet to reduce 4πMs and increase stability to temperature.
Shrinkage volume by reducing/losing the pores of the material during the sintering process may occur through a mechanism of evaporation of condensation, lattice diffusion, diffusion of grain boundaries, surface diffusion, or a combination thereof.
Garnet soft ferrite shrinkage is dominated by the mechanism of diffusion of grain boundaries, along with lattice diffusion.
This structure occurs if the granules in a certain area in which the growth of the grain is faster than in the other regions.
Besides the number of turns, the frequency given also affects the performance of the resulting hysteresis loop.

It is the essential attribution of soil which controlled by grain size and clay minerals composition, despite of the effect of external variables.
The particle size, mineral and chemical composition, secure level of the junction between grains, surface energy and relative surface characteristics of soil will be changed with the development of specific surface area, all of them are the influencing factors about physicochemical and engineering properties of soil.
Cerato et al had analyzed the determination of surface area of fine-grained soils by ethylene glycol monoethyl ether method [5].
The relationship between specific surface and MB used is equation 1 (1) Where SSA is specific surface area of soil (m2/g), N is the number of MB increments added to the soil suspension solution, AV is Avogadro’s number (6.02×1023), AMB is the area covered by one MB molecule, typically assumed to be 1302.

On the one hand, the fatigue life in vacuum at room Fig. 2 Dimensions (in unit of mm) of sample used in fatigue testing of Ti-6Al-4V alloy Fig. 3 Schematic of the MYBP-type fatigue test machine 1. loading shaft 2. screw cap 3. airproof pad 4. thermocouple 5. crossbeam 6. specimen 7. standard ergometer 8. circular flange 9. copper clamp temperature is longer than that in air, especially at the low stress amplitudes where the number of cycles to failure in vacuum is approximately an order higher than that in ambient air.
Fig. 4 Fatigue S-N curves of Ti-6Al-4V alloy 10 4 105 10 6 10 7 500 550 600 650 700 750 800 850 293 K, air 293 K, 10 -3 Pa 100 K, 0.5×10 -3 Pa Stress amplitued σa, MPa Number of cycle to failure Nf, cycles R= -1 f= 25 Hz In order to gain a better insight into the effects of vacuum and low temperature on the crack initiation and propagation, SEM investigations were conducted on the sub-cracks in the cross-sections close to the fracture surface, as shown in Fig. 6.
It can be seen that the cracks in air environment mainly initiate and grow along the primary α (αp) grain boundary, as shown by the arrows in Fig. 6a.
At room temperature in vacuum, the cracks mainly grow in the interior of αp grain through the conjunction of several voids which act as small cracks, with occasional cracks growing along the αp grain boundary (Fig. 6b).

Table 1 Rock Parameters Table Parameters Rock Layer Lithology Description Poisson's Ratio Elastic Modulus (GPa) Density kg/m3 Cohesion (MPa) Angle of Internal Friction Tensile Strength (MPa) Old Roof Sandy mudstone 0.23 23.5 2540 1.5 30 4.06 Old Roof Fine-grained Sandstone 0.23 26.8 2650 1.6 35.5 8.60 Immediate Roof Sandy Mudstone 0.24 23.5 2400 1.8 25 1.20 Coal 0.30 14.7 1500 1.2 25 2.0 Immediate end Sandy Mudstone 0.29 18.9 2570 1.5 30 4.62 Old End Fine-grained Sandstone 0.21 25.9 2650 1.6 35.5 8.60 Table 2 The Calculation of Parameters of the Supporting Structure Support Material Elastic Modulus (GPa) Elastic Limit (MPa) Tensile Strength (Mpa) Length (m) Diameter (mm) Roof Bolt 210 425 590 2.0 22 Roof anchor 195 ＼ 1730 8.4 22 Bolt on Sides 210 425 590 2.0 22 Anchor on Sides 195 ＼ 1730 5.3 17.8 Roof beam 200 265 405 5.1 16 Beam on Sides 200 265 405 4.5 16 Analysis of Simulation Results.
In the numerical simulation, the model of Surrounding Rock of Roadways is the isotropic Elastomer-Plastomer, which between unit cannot be separated, but in the practice, there are a large number of joints and cracks in the surrounding rocks, the surface of the surrounding rock of roadways would peeling, shedding after damage, which led to the destruction continue develop to the deep, especially more intense after stopping the mining.
Improving the density of the support can reduce the number of damage to the surface of surrounding rock, which can reduce its peel and shed in practice.
Combined results of the analysis and the actual geological conditions of the mine, the immediate rock is sandy mudstone and its average thickness is 4.8m, the main roof is fine-grained sandstone with an average thickness is 9.2m, so the reasonable length of anchor cable is 7.5m.

Pavement structure diagram The type of the structure layer The materials of each layer The thickness of each layer（cm） Profile diagram surface course The above layer Fine grained type asphalt AC-13 4 The piezo- electric layer The above layer The middle layer The following layer Base course Cushion layer Subgrade The piezoelectric layer Bituminous ortar ＜1 The middle layer The grain type asphalt AC-16 5 The following layer The grain type asphalt AC-20 6 Base course Cement stabilized debris 40 Cushion layer Natural debris 15 Subgrade —— —— Table 3.
The result of the BISAR 3.0 Position Number Layer Number Depth(m) ZZ Stresses(MPa) 1 1 4.000E-02 -6.703E-01 2 2 9.000E-02 -5.144E-01 3 3 1.500E-01 -3.271E-01 4 4 5.500E-01 -1.297E-02 5 5 7.000E-01 -7.079E-03 We get the stress response of different deepness of the road and the calculation results are drawn into line in Fig 2

A number of research efforts have been made to choose optimal milling parameters.
Zhang et al. [14] applied the Taguchi approach to determine effects of ball milling parameters on the grain size and specific surface area of WC powders.
This approach provides reliable results based on a relatively small number of experiments.
The numbers from 1 to 9 indicate the experiment number.
[8] Y.Ogino, M.Miki, T.Yamasaki and T.Inuma, Preparation of Ultrafine-Grained TiN and (Ti, Al)N Powders by Mechanical Alloying, Mater.

Needle-like grain particles with a width about 200 nm and a length about 1 μm are observed.
These needle grains form big needle-array particles with a size about 2 μ in diameter.
The direct band gap of the α-Bi2O3 nanoneedle arrays is determined by fitting the absorption spectra data according to the equation (αhv)2=B(hv-Eg) [16] (α is the absorption coefficient; hv is the photo enrgy; B is a constant number; and Eg is the absorption band gap energy).

Research priorities at home and abroad focused on optimizing the alloy composition, grain refinement and modification on microstructure and properties of the impact of research for less density [3~5].
Orthogonal pilot program in accordance with the table number 9 group of specimens corresponding to each set of cycle parameters on the corresponding liquid aluminum applied current, magnetic field strength, cycle time, the use of anti-gravity casting method electromagnetic pump casting specimens.
Aluminum alloy with grain refiner of [J].