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There are a number of dynamic constitutive models for metals under impact loading that have been obtained from dynamic tension, compression, and torsion tests and used to describe the Von Mises flow stressof metals as a function of the equivalent plastic strain, the equivalent plastic strain rate, and the temperature .
For FCC metal, Z-A model is (12) whereis the microstructural stress intensity, is the grain size, ，，， are material constants.

Zavattieri et al. [2] investigated the dynamic fragmentation of ceramic microstructures, in which the open-up and growing of micro-cracks were assumed along grain boundaries.
Normal force (F) acting on an atom (i) on plane (a) from atoms on plane (b) is ∑== n1j ij ij )120( i r d )r(fF (1) where rij is the distance between atom i on plane (a) and atom j on plane (b); d is normal distance between two planes; n is the number of atoms on plane (b), which is chosen to be 22. f(rij) is force between atom i and atom j, defined from Morse potential [10].

Fig. 4(a) is the surface photography of the as-grown ZnO film, from which some accumulated shape consisted by a number of 30nm columns can be seen.
The surface of the film becomes flatter after annealing in air at 550 o C for 1 hour, and the well-regulated grain boundary with hexagonal structure of the columns appeared (see Fig. 4(b)).

Due to high efficiency of heat extraction and massive number of particles that arrives in the preform, associated to the spray atomisation, low temperature can be maintained during the process and deleterious interfacial reactions can be minimised.
It is usual to obtain a uniform microstructure, with fine grains and with little segregation, contrasting strongly with the coarse structure, segregated and dendritic of the materials conventionally cast.

Table 1 3# test drilling geological record table Drilling Depth phenomenon description 0~1.0m gravel (the gravel when filling the pavement) 1.0~2.2m loose strong weathering basalt 2.2~3.8m Drills-down phenomenon, lava hole(cavity) 3.8~4.6m broken, loose strong weathering basalt 4.6~7.2m broken, big pore ratio basalt 7.2~8.8m very broken basalt 8.8~10m complete, Close-grained basalt (2) Small cavity concentrate area: To present the obviously strong amplitude reflection area in the radar profile, but the abnormal reflected wave is mixed and disorderly, arc reflection wave area is smaller, disorderly reflection wave is more and it can't be more present continuously, abnormal reflection wave frequency is higher
Project Serial Number: 2011318346770 References: [1] D.F.

This indicates the manifestation of the collective properties of hydrogen atmosphere in metals and is reflected in a number of non-linear effects, in particular in the dependence of the output rate, diffusion coefficients, the dependence of the hydrogen atoms energy on the density and energy of the exciting electron beam.
High concentrations of hydrogen result in the formation of the metal hydrides alter the grain boundaries, the porosity of the material and influence the hydrogen diffusion [13].

The carbide stuff of the adopted twist drill is YG6X and YL10.2 whose grain size is less than 1.0 mµ and 0.8 mµ respectively.
Figures show that the number of chip folding in common drilling is much more than that in vibration drilling, that is, the deformation degree of chips is larger in common drilling.

The relatively huge crystal grains of the kaolinite, which have pseudomorph of feldspar and mica, can be seen under the micropolariscope.
Fatty acid sodium was prepared by mixing oleic acid (analytically pure) and NaOH, whose molecules number is equal to oleic acid, and then stir several hours at heating condition.

Introduction Low carbon steel is widely used in a large number of applications including automobile frames, pipelines, ship plates, bridge beams etc.
We observe also that the microstructure of the coating prepared at 100mm is more dense with fine grains than the coating obtained at 120 and 140mm respectively, and the corresponding splats are thinner at 100mm In order to explain the microstructure of the three coating, image analysis was used to determine the porosity fraction, and Vickers microhardness measurement using a load of 200g for 15s to (a) (b) (c) Fig.2.

A total number of 1.5 x 10 4 cells were cultured on each sample.
On the surface oxidized with H2SO4, the AFM image reveals that regions between pores are rough, composed of small Ti oxide grains.