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A great number of researchers have applied themselves to the study of production technology and properties, such as hardness, strength and other properties of Al2O3p/Cu composite [9~11].
It is also evident that a number of parallel and continuous wear grooves exist on the worn surface of 0.60Al2O3p/Cu composite in the direction of the motion in Fig.7 (a) (b)，which is characteristic of an abrasive wear mechanism.
In addition, a large number of small spherical droplets particles are observed on the worn surface.
The dispersion distributed Al2O3 particles can increase the recrystallization temperature and exhibit excellent strength at elevated temperatures by pinning down the grain and sub-grain boundaries of the copper matrix and impeding the movement of dislocations.

Ion mobility determines both rate and possibility of the great number of solid state, catalytic and ion exchange processes.
It also explains a great number of properties of solids such as plastic or elastic deformation, electronic or ionic conductivity important for their application in sensory devices, fuel cells etc. [1-4].
Bokstein: Do you think that ion diffusion along grain or phase boundaries is compatible with diffusion through (across) the grain boundary?
This diffusion is slower, of coarse, but it is very important for a number of chemical processes.

Although the HVPE-GaN seed crystal is almost opaque due to a lot of included grain boundaries, the transparency of the LPE crystal (a result of the LPE growth that filled in the boundaries) is sufficient to be able to discern the characters through the crystal, as shown in Figure 4.
We estimated the number of dislocations included in the crystal from the etching treatment in the 500 ºC NaOH melt.
In the circle in Fig. 6b, a light scattering due to low-angle grain boundaries that should be derived from the coalescence of the facets can be seen just under the dislocation line.
Although bent dislocations may move outside the sample, TEM observation indicates that the number of dislocations should be drastically reduced.
Thereafter, the number of facets decreased as thickness increased and a (0001) face started to develop.

In addition to the solid and liquid phase, a phase related to the interdendritic liquid which is enclosed within a dendritic grain is introduced [11].
The distinction between extradendritic and interdendritic liquid is based on the notion of an envelope, which connects tips of a dendritic grain [12].
The influence of a magnetic field on fluid flow is characterized by several non-dimensional parameters which are the skin layer δ normalized by the pool radius R, the interaction parameter � and the magnetic Taylor number mTa .
Dimensionless numbers and parameters applied in simulation
Time of formation of a sole lateral "tree branch" is about s30 and during this period a number of vortices dissipate in a mushy zone.

By using radioactive isotopes of Co-57 and Am-241, the energy calibration formula was calculated as follows: En = 0.059066×CH + 0.37067 [KeV], (1) where CH is a channel number of MCA.
Integrated intensity becomes so high that there are many crystal grains which satisfies X-ray diffraction conditions.
Acknowledgement The synchrotron radiation experiments were performed at the BL28B2 of SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal Number 2012B125).
And this study was supported by JSPS KAKENHI Grant Number 24560083.
Weertman, Dislocations, grain size and planar faults in nanostructured copper determined by high resolution X-ray diffraction and a new procedure of peak profile analysis, Acta.

One simple method to calculate this value is [5]: (3) where dg is the approximate grain diameter and C1 and n1 are constants.
For the wheel used,the approximate grain diameter equals dg = 0.19 mm.
The punch grinding cycle can consist of a single, a few or multiple passes, depending on the number of workpiece rotations required to removetotal stock.
The optimization problem can hence be written as: • minimize grinding cycle time tc • subject to: qm ≤ 600 ºC nw ≤ 100 rpm vfr ≤ 10 m/min The optimal number of grinding passes that yield minimal grinding cycle time is not known in advance.
The optimization problem is solved by the simulation model that yields optimal number of grinding passes and grinding parameters satisfying the optimization objective and constraints.

Despite the attenuation of compressive residual stress in the initial stage of operation, but when the cycle is up to 104 times, the number will tend to be steady and will still have a high level of residual compressive stress.
Under combining ultrasonic impact with static pressure function, metal surface evenly produces plastic deformation, which makes part surface and sub-surface causes a large number of dislocations and holes，it can make original state grain distance certain depth from the surface refined to obtain the corresponding nanometer structure layer[9].
It was claimed that the joint surface formed grain refinement layer whose thickness was about 100 ~ 150 μm.
Haagensen et al[15]of Norwegian University of Science and Technology took ultrasonic impact treatment to Weldox700 of high strength steel, the fatigue strength of sample increased by 121% after UIT, Andre Galtier[16] conducted respectively ultrasonic impact treatment to steel welded joint of USI FORM 355 (FY = 355 Mpa) and USI FORM700 (FY = 700 Mpa), Study found that welded joint fatigue strength of USI FORM355 steel increased from 320 Mpa to 480 Mpa which increased by 50% and welded joint fatigue strength of USI FORM700 steel increased by 67% in fatigue condition of the stress ratio R = 0.1, cyclic number N = 2 x 105.

The microstructural characterization of seventy samples cut along the fabrication process was performed using a number of techniques [3].
At the output of this extrusion, δ and ε are essentially located in the α-matrix grain boundaries and at a shorter than 50 micrometers distance from the interfaces of the filaments belonging to the two most central rows [3].
Such an efficiency increases with both a diminution of the distance between the filaments and the reservoirs, and an augmentation of the number of solute atoms available for the reaction.
This number of atoms increases with the volume and/or the primitive Sn-content of the reservoirs.
Moreover, the compression of the Nb3Sn layer is also of chief importance for its grain size and internal strains, and thereby for the superconducting behaviour.

A large number of testing and engineering practice show that the load peak of fatigue failure caused by vibration is often much less than the static security load that estimated according to fracture analysis.
As the fatigue of actual material are the cumulative damnification in a certain range (usually a number of grain size), so some of the fatigue phenomenon can not be explained by the "fatigue design" of point theory (point stress, point strain, point energy, etc.).
The mathematical expression of the two parameters σ, ε, can be shown as follows ∫=Ω ij vrf V d)()( 1 ϕσ σ （7） ∫=Ω ij vrf V d)()( 1 ϕεε （8） where: Ω is the local damage region, which is a number of grain size in general for the fatigue problem.

Introduction The pneumatic vibration sieve cleaning device is wildly used in all kinds of crops for its simple and ideal effect[1-4] .Such as vegetables, tea, peanut and all kinds of grain were studied by scholars, but there were not many studies about ginkgos’ physical characteristics and cleaning device, the article designed a cleaning machine based on ginkgo’ suspension speed and its physical characteristics.
Table 1 Results of suspension speed test for Ginkgo seed Number Ginkgo fruit Ginkgo nuts Ginkgo fruit shell Vmin(m/s) Vmax(m/s) Vmin(m/s) Vma(m/s)x Vmin(m/s) Vmax(m/s) 1 14.3 14.5 15.3 15.6 6.3 6.3 2 13.8 14.1 15.9 16.1 7.5 7.7 3 13.9 14.2 15.2 15.4 6.3 7.1 4 13.7 14.0 15.6 15.9 7.3 7.5 5 13.8 14.1 15.5 15.8 6.8 7.4 Mean 13.9 14.18 15.5 15.76 6.84 7.2 Fig.1 Structure diagram of Ginkgo cleaning device 1. feeding hopper; 2.hopper control board; 3.fan; 4.belting; 5.eccentric gear; 6.electrical machinery; 7. fruit aggregate bin; 8.unhulled fruit aggregate bin; 9.vibrating screen; 10.inlet scoop; 11.air outlet; 12.body frame．
Table 3 Experimental design and results Number Code Response Feed quantity A（g/h） Wind speed B （m/s） Outlet angle C（°） Loss rate Y1（%） Cleaning rate Y2（%） 1 1 1 1 17.16 96.32 2 1 1 -1 19.82 97.44 3 1 -1 1 0 86.02 4 1 -1 -1 3.38 88.89 5 -1 1 1 13.79 94.64 6 -1 1 -1 15.93 95.24 7 -1 -1 1 2.65 89.44 8 -1 -1 -1 1.48 91.21 9 1.682 0 0 4.91 93.41 10 -1.682 0 0 3.89 95.54 11 0 1.682 0 29.57 97.42 12 0 -1.682 0 8.01 85.38 13 0 0 1.682 0 94.06 14 0 0 -1.682 3.51 96.54 15 0 0 0 6.38 95.31 16 0 0 0 5.29 95.48 17 0 0 0 5.57 94.94 (1)Regression model.
Tab. 6 The verification results of prioritization scheme 　Test item Serial number 1 2 3 Mean Cleaning rate（%） 94.72 96.73 95.84 95.68 Loss rate (%) 0.88 1.32 2.85 1.68 The experiment results shows that the loss rate, the cleaning rate were very close to the theoretical value, which indicats that the regression model established for the analysis and prediction of the clear effect of ginkgo’ fruit hulling was feasible.
Aerodynamic properties of grain/straw materials[J].Journal of Agricultural Engineering Research, 1990,Vol. 46,p.275-290