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About 80 percent of grains locate in 1-2 μm (Fig.1 (b)), and the relative density measured by the Archimedes method is 99.47±0.46% of theoretical density.
Therefore, in individual grains it is conceivable that the crack extending on the (001) plane causes a smooth fracture surface.
Indeed, the cleaving process of the crystal plane will be interrupted when the crack encounters grain boundaries.
Due to misorientation, the crack changes its fracture surface from the cleavage plane of one grain to that of another and its deflection angle is exactly equal to the intersection angle of both cleavage planes.
Except for grain boundaries, the growing crack does not encounter a greater number of microstructural obstacles.

For example ceramic nanofibers in superconductive single grain bulk samples can play double role: physical pinning and mechanical reinforcement – by increasing the fracture toughness [4].
Upon applying a high voltage to the electrospinning system, an enormous number of solution jets can be generated upward from the roller surface.
Ceramic fibers consist of the small rutile grains, 50-70 nm in size.
Information about the morphology, mean size of the prepared precursor and ceramic polycrystalline fibers and grains are gathered in the Table 1.
Yang et al, Effect of ZnO/TiO2Nanorods Fabricated Using the Electrospinning Method in Y-Ba-Cu-O Single Grain Bulk Superconductors, IEEE Trans.

Incorporating metallurgically stable, uniformly spaced, strong and fine ceramic grains in the alloy is one way to improve resistance at high temperatures [8, 9].
Experimental Work Table 1 summarizes the specific powders utilized in the present study's specimen preparation, together with their grain size and purity.
Throughout the first stage of sintering (600 oC for 600 min), figure (1) demonstrates the beginning of the bonding phase between the Al and Ni grains, whereas Figure (2) demonstrates the structures compositions throughout that stage.
The Composition Structure by XRD between Al and Ni grains throughout sintering post-Sintering Processing at 600OC for 600min.
Mutasa 1997“Defect structures in Ordered Intermetallics; Grain Boundaries and Surfaces”, PhD Thesis, Blacksburg, Virginia

The segregation may take place inside as well as on the grain boundary.
They contain such modifiers as Zr, Cr and Ti, which stabilize the structure, prevent grain growth and also decrease susceptibility of welds to cracking.
The analysis of the chemical composition revealed that the structure of the parent metal consists of the grains of zinc solid solution in aluminium a-Al and precipitates of inter-metallic phases rich in Si, Mg, Cu and Fe.
The HAZ of joint C23 also contained tiny globular precipitates inside the grains as well as on the grain boundary, which can indicate the presence of Al2Cu and MgZn2 phases (Fig. 6).
A smaller number of precipitates in the crack areas could have led to the lack of precipitation hardening and resulted in lower mechanical properties.

The results showed that doping with La3+ and Co 2+ could suppress the growth of TiO2 grains and increase the specific surface area; When the calcination temperature increased from 300°C to 900°C, the average crystallite size of the particles increased from 7.3nm to 35.6 nm and�the specific surface area of the particles decreased rapidly from 205.5m2/g to 41.2m2/g.
Recently, a number of methods have been pursued in order to overcome the above defects.
The average grain size and distribution were measured by small angle X-ray scattering goniometer (SAXS).

On the other hand, at high temperatures the precipitation is often uncontrolled and a recovery of the ultrafine-grained microstructures may occur.
Cylindrical billets of 10 mm in diameter and 70 mm in length were pressed through an ECAP die with 90° intersecting channels at RT for different numbers of passes in route BC (the billet was rotated around its longitudinal axis by 90° between intermediate passes) at a constant displacement rate of 8 mm/s.
Table 1: Microhardness and estimated yield strength of supersaturated AlZnMg samples investigated under different conditions Alloy Aging time at RT Actual number of passes by ECAP in route Bc Number of passes to failure Subsequent aging Hardness [MPa] %5± Estimated yield strength [MPa] 1. 1 week 1 1 - 2000 ∼670 2. 1 week 1 1 100 oC (24h) 2020 ∼670 3. 10 min. 3 3 - 2080 ∼690 Al-5.7Zn-1.9Mg-1.5Cu 4. 10 min. 1 - - 2070 ∼690 5. 10 min. 1 - 100 oC (24h) 2020 ∼670 6. 10 min. 1 - 140 oC (24h) 1550 ∼520 (Peak strength in conventional mater.) 7. 2 months - - 100 oC (24h) 1480 ∼490 8. 10 min. 4 4 - 1540 ∼520 Al-5.7Zn-1.9Mg 9. 10 min. 4 4 100 oC (24h) 1690 ∼560 10. 10 min. 4 4 140 oC (24h) 1280 ∼430 11. 1 week 3 3 - 1350 ∼450 12. 1 week 1 - - 1360 ∼450 13. 1 week 1 - 100 oC (24h) 1390 ∼460 14. 1 week 1 - 140 oC (24h) 1150 ∼380 15. 1 day 4 4 - 1340 ∼450 16. 1 day 1 - - 1320 ∼440 17. 1 day 1 - 100 oC
However, for a given alloy composition, the strength gained after ECAP seems to depend neither on the time period of pre-aging at RT (see samples 1 and 4, or samples 12, 16 and 21) nor on the number of passes of ECAP (see samples 1 and 3, as well as samples 19, 20 and 21).
It should be noted that the application of more passes (e.g. up to 4 passes) is more important if the increase in strength is brought about by the Hall-Petch effect as a consequence of grain-refinement [21] or in the case of deformation mechanisms like grain-boundary sliding [22-24].

SCLP offers a corrosion-resistant overlay with a number of advantages, such as reducing the capital cost of providing high corrosion resistance whilst retaining the high machinability and strength of ferritic steel.
It can be seen that martensite grain size was very small and uniform, which improved the mechanical properties of the substrate and was beneficial to increase hardness and wear resistance.
As seen in Fig. 3(c), substrate microstructure away from the interface consisted of ferrite and pearlite grains, which implied no phase transformation occurred.
Substrate microstructure away from the interface consisted of ferrite and pearlite grains.
Microstructure of cladding layer is composed of a large number of dendrites and a small amount of cellular crystal

On mechanical properties, higher Young's modulus and hardness values follow to increase the TiN/NbN layers number.
Fig. 3 shows the TiN/NbN multilayer films produced for different total number of layers of 4, 16, 32 and 64 and total coating thickness of 1.9µm to 2.1µm on as-annealing.
These surfaces revealed that the TiN/NbN multilayer coatings consisting of up to 64 alternating layers had much smaller grains and uniform dense.
It can be seen that with increased number of 8 and 16 layers resulting in a decreased the friction coefficient from about 2.0 to 1.5.
Moreover, it is interesting to note that the number of 64 layers showed relatively smaller friction coefficients as compared with 32 layers coating.

The four wood components were numbered A, B, C, D.
The length direction of the specimen is same as wood grain direction and the cutting was based on Chinese standard (GB1929-91).
Size and number of the specimens are listed in Table 1.
Table 1 Size and number of specimens Specimen No.
Method of testing in impressive strength parallel to grain of wood.

Virtualization energy saving strategy Virtualization technology is one of the key technologies of cloud computing, virtualization technology allows you to create multiple virtual machines on a host at the same time, this can reduce the number of hardware resources, improve resource utilization [3,4].
Nguyen et al [5] using a constraint satisfaction problem CSP (constraint satisfaction problem) on the deployment of a virtual machine modeling constraint is the user's service level agreement SLA, the goal is to maximize energy savings realized idea is to maximize the number of physical machines idle by powering off the physical host to save energy.
Energy saving method based virtual machine migration Define virtual machine deployment issues for a global virtual machine allocation matrix , represents the number of virtual machines j assigned to the application i, and virtual machines between hosts is represented by a matrix P, said the virtual machine when bbb v assigned to the host h.
Off the free / open energy saving strategies are usually shut down the server for / on set or predict the timing, but in terms of cloud computing system contains a large number of types of computing resources, and how to determine the number of servers to be shut down according to the task per unit time arriving , as well as issues such as which servers shut down, gave off / on energy saving strategies to bring the problem.
DVFS are fine-grained energy saving, the latter two belong to the coarse-grained energy saving methods.