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As the annealing proceeds, the number and sizes of these nuclei increase until they form a continuous layer, through which the new portions of Sn diffuse from the bronze matrix into Nb filaments.
From three regimes of the diffusion annealing (А, G and H), which resulted in the highest critical current, the greatest number of filaments with the residual Nb are present after the one-staged low-temperature annealing in spite of the long holding (Fig. 3, regime A).
A number of other regimes were tested for the improvement of the nanocrystalline structure of superconducting phase and the enhancement of the critical current (see Table 1).
The grain size scattering increased markedly both within one filament and between sections of different filaments, the average grain size increased as well and some grains the sizes of up to 300-350 nm appeared.
Critical currents of the wires with ring Nb filaments annealed by various regimes versus average grain sizes of superconducting Nb3Sn phase Thus, the analysis of structure and morphology of superconducting Nb3Sn layers in composites with ring filaments, based on TEM and SEM data, has shown that the critical current of the superconductors is affected by a number of factors, such as the completeness of Nb filaments transformation into Nb3Sn (the residual Nb amount), morphology of superconducting layers (the presence or absence of columnar grains), average grain sizes of Nb3Sn and grain size scattering.

This paper presents a system based on wireless sensor network (WSN) for granary monitoring including grain temperature and grain moisture content monitoring.
Each sensor module includes two sensors: grain moisture content sensor [6] and temperature sensor, which can be used to measurement the moisture content and the temperature of grain, respectively.
While, the corresponding four sensor modules are placed in grain, which can measure the moisture content and the temperature of grain at the height of 0.5m, 2.2m, 3.9m, 5.6m, respectively.
The Re-TX information field contains 8 bytes, each bit (bit0 … bit63) is on behalf of one node, and the bit number is coincided with the time slot ID of a sensor node.
Conclusion This paper presents a system based on WSN for granary monitoring including the grain moisture content monitoring and the grain temperature monitoring.

The mechanical ball mill has a balls and vials were the powder experience high rate of strain resulting plastic deformation with dense number of dislocations.
As the process of dislocation reaches to specific point, they break to sub grains. these sub grains further deformed to fall to nanometer scale.
The particle structure and grain size of Magnesium AZ31B alloy was determined using Optical Microscope (Olympus -Gx71), SEM (Tescan-Vega 3) will be utilised for determination of grain size and Fracture morphology.
Agglomeration of nano Sic Grain Boundary Particle Boundary a Agglomeration of nano Sic Grain Boundary Particle Boundary b Agglomeration of nano Sic c Fig. 3.
Therefore, the hardness was well improved due to relative density and grain size at the sintered temperatures of 4750C.The sintered temperature has caused to increase the relative density and bonding of grains increased, causing large dislocation of particle and grain boundaries.

Introduction Due to an insufficient number of operative slip and twinning systems (only {0001}<110>basal slip and mechanical twinning), magnesium alloys exhibit a limited ductility and poor formability at room temperature.
There are various SRX mechanisms reported, such as grain boundary migration (GBM), grain boundary bulging (GLB), sub-grain rotation (SGR) and twining mechanism.
An obvious increasing the number of frequency of HAGBs with the increases of annealing temperature is shown in Fig. 2.
The strain-low grain (grain 1 in Fig. 4a, I) grows at the expense of the more strained grain (grain 2) causing the undulation of boundaries following by dislocations drunk in, and subsequently result in boundary of grain 1 bulging into grain 2 leaving a strain-free region behind the migrating boundary at the subsequent thermal assistance.
Therefore, there are diverse microstructural evolution mechanisms such as Grain Boundary Migration (GBM), grain boundary bulging (GLB), sub grain rotation (SGR).

In the end of the 20th century, LU [3] proposed the concept of metal surface auto-nanocrystallization, namely, by using external mechanical load to make the metal surface occur a strong plastic deformation and introduce a large number of non-equilibrium defects and interface to refine the conventional coarse grain to nanocrystals.
Observed from the morphology, we can find that the surface grains have been refined into the equiaxed nanometer grains with the size of 10nm-30nm.And it is difficult to identify their apparent grain boundaries.
This makes the material surface get the continuous multi-directional high stress and strain rate, which results in a large number of defects.
Due to the expansion of the accumulated compressive stress and tensile stress, the twins move leads to more crystal surface slip, which eventually forms a large number of dislocations.
After HEBMT, the surface grain can be refined to 10nm

The creep mechanism of the composite is dislocation and grain boundary sliding control.
The current study results of magnesium alloy creep show that their creep deformation mechanism is dislocation slip mode and grain boundary sliding mode[9].
The non-continuous precipitation organizations make the movement and slip of the grain boundary be able to be carried out easily; while the movement and slip of the grain boundary carry through the form of dislocations, the creep fracture surface of the specimen must have obvious steps.
At a high temperature, plastic deformation of the matrix should be evident, that is, there exists a large number of dimples; and the fracture surface with clear micro-cracks.
In the preparation process of the composite material, because of a small number of poor bonding interfaces between the fibers and matrix, there are flaws and micro-cracks.

The average grain size changes with the sintering conditions.
Obviously, the grain growth is restrained during ultrahigh pre- ssure sintering [9].
The grain shape also changes from round-like to irregular with increasing pressure.
ceramics with large-sized grains.
Acknowledgements This work was supported by NSFC of P.R.China under grant number 50272040, Fok Ying Tong Education Foundation under grant number 91046, and Youth Science and Technology Foundation of Sichuan Province.

Grinding process becomes very complex and difficult to analyze, because the distribution of abrasive grains is stochastic and abrasive grain geometrical shape is anomalistic.
Because the number of cutting points is large, cutting point geometrical shape is anomalistic, grinding velocity is high, every abrasive grain's cutting depth is small and inconsistent, especially the spark eject from grinding wheel, all of these make the process become elusory.
We know there are large numbers of cutting points whose geometrical shapes are inconsistent arrange irregularly on the surface of grinding wheel and their positions and directions are stochastic, So the cutting geometries of abrasive grains are different each other.
In order to make the simulation close to true grinding process, we should get a universal ubiety (abrasive grain 1 and 2. in Fig.2), the height of abrasive grain 1 is higher than the height of abrasive grain 2 and the abrasive grain 1 locate top left direction of the abrasive grain 2.
From Fig.5 we can see the area ABCE is cutting volume of abrasive grain 1 and the area BCD is cutting volume of abrasive grain 2.

As shown in Fig. 3, the as-forged Ti-47Al-2Cr-2Nb-Y alloy has refined streamline microstructure along radius direction composed of a large number of recrystallized grains and a small amount of retained casting lamella colonies.
At high temperature, disordered β phase could provide a sufficient number of slide systems and carries most of the deformation [7, 15].
This overcomes limited number of slip systems of the room temperature deformation in TiAl based alloys.
Strain compatibility among different grains is also improved.
Disordered β phase with bbc lattice provides a sufficient number of independent slip systems, which improves tensile properties.

The gradual reduction of grain size with increasing ultrasonic output power can be attributed to an increase of the nuclei number formed in the initial crystallization period.
The average grain size was 120µm.
With increasing the treating time, the grain size of the alloy was reduced.
In this way, a large number of nuclei can be produced during the expansion stage.
Thus, the grains of the Mg-3.0wt.