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Its phase composition and microstructure were characterized by using XRD, SEM,and its high temperature anti-oxidation property were studied by isothermal oxidation tests.The results showed that the coating is composed of mainly α-SiC and β-SiC,the coating is uniform, compact, perfect grain growth, without crack, closely with the C/C materials,the thickness is about 600μm.
In the first stage, carbonaceous material on the surface of C/C composites reacted with siliceous gas of the furnace and formated SiC; in the second stage, a large number of SiC was synthesized in furnace when the temperature of furnace core reached the 2600 [12], at so Fig. 1 XRD patterns of SiC coating high temperature, the surface of synthesized solid-phase SiC which easily decomposed or evaporated and turned into vapour was called SiC reactivity gas, such as Si,Si2C,SiC2,SiC, the gas agglomerated, deposited and reacted in the pores structure inner ceramic coating formating SiC.
From Fig.2b, it can be seen that large SiC grains together with micro-crystals are both present on the coating surfaces, its morphologies mainly be composed of well-crystallized, hexagonal, dense SiC crystal, which is advantageous to improving the oxidation resistance of the coating.
The transition layer with a thickness of around 200μm is not very dense.This layer was formated by reating carbon residue with SiO gas and generated SiC, which keeped vitreous carbon structure with a large number of porous structure; reating substrat with SiO gas and generated SiC,which had same structure with the matrix, therefor there had a perfect transition gradient of phase structure from C to SiC and good associativity, the coating had good chemical compatibility with C/C composites,it will be avoid that the coating occur crack,even separate from substrat because expansion coefficient mismatch during high temperature environment.
In the first stage, resin of the coting was carbonized and formating high-carbon residue vitreous carbon at high temperature, at the same time gas SiO, Si, SiO2 , etc of SiC industrial synthesis furnace diffused into the porous structure of the coating and reacted with those vitreous carbon, petroleum coke, then formated SiC, which retained the structure of carbon network porous structure, this stage occurred in the early stage of synthesis SiC; the second stage was the key stage of obtaining excellent performance of high temperature anti-oxidation coating, to occurr in the later stage of synthesis silicon carbide, a large number of SiC synthesized in this furnace easily evaporated and turned into gas Si, Si2C, SiC2.

Carried on an observation to the variety that vegetation dam’s in front and back single grain sediment sport speed, and silted up appearance with the sediment in the dam to carry on analysis before the dam to the plant.
Introduction Plant "flexible dam" in the channel or canals, the main tank, and by certain plant spacing and line spacing, planting a certain number of sea buckthorn tree [1] Sea buckthorn is an Elaeagnaceae shrub, it has developed the spurious branches prone to deflection in the hydrodynamic effect, so called "flexible dam".It can slow down the rate of water flow, intercept flood backdrop of a large number of coarse sand, which is mainly of bed load sediment, sand fixation and restore the ecological role[2,3].
Model tree lined optimized water test water blocking the best of the 6 cm × 9cm × 9 ranks staggered arrangement shown in Figure 1, 6cm for the spacing in the rows, 9cm for spacing, 9 is the number of rows, 72cm dam planting a tree for 63 planting density of 248 / m2.
Table 1 Single grain damping extent in average sport velocity after planting table bottom slope Particle size(mm) flow(L/s) 5.09 9.08 13.08 1/150 4~5 100% 76.29% 76.76% 3~4 100% 79.03% 74.88% 2~3 100% 80.96% 76.30% 1~2 100% 81.77% 74.31% 1/100 4~5 29.55% 23.21% 19.88% 3~4 26.65% 22.86% 20.95% 2~3 26.86% 20.58% 21.04% 1~2 32.99% 17.29% 20.85% 1/50 4~5 8.05% 19.16% 18.75% 3~4 7.06% 19.58% 21.70% 2~3 7.69% 12.27% 20.87% 1~2 0.92% 11.68% 19.40% Longitudinal Analysis of Sediment Deposition The different flow of the bottom slope, sediment deposition thickness along the vertical increases gradually and forms a peak in front of the dam.

The B2 phase grains are highly deformed and contain large number of defects.
The particles are difficult to be found in the TEM images which is due to their small sizes and also presence of quite a number of defects.
It is caused by its complex and not uniform structure of the sample containing large grains and small nanograins, lot of defects thus in different regions of the sample the transformation occurs at slightly different temperature. 4.

However, Liao et al [5] found that the modification of Al-Si alloys with Sr addition increased the size of the eutectic grains and reduced the number of eutectic grains.
The number of the needle-like eutectic Si is decreased. 100 μm a) b) 100 μm Fig.3 Microstructures of Al-40 Si alloys before (a) and after (b) heat treatment Fig.4 presents the microstructures of Al-40Si alloys suffered different deformation ratios.

Because of the discrete character of soil, the properties depend on composition, form, size or surface state of grains, this approach is not well predict what is happening at the microscopic level.
Moreover, it introduces many parameters that require a large number of identification experiments.
In addition, most continuum approaches do not account for grain-scale mechanisms.
It is regarded as an assemblage of a finite number of discrete elements with the predefined geometry and given material properties.

An increasing number of ears reduces the absolute ear height.
Each integration point can represent one orientation or a set of grain orientations when combined with a homogenization model.
In order to achieve this goal they used a large number of integration points in conjunction with a crystal plasticity finite element formulation.
Each rotation matrix mapped at an integration points was assumed to represent one grain.
An increase in the number of ears entails a drop in the ear height.

.%, the grains were clearly visible, and as the Al doping increases to 1.5 wt.% or higher, the grains are not distinguishable.
The impedance plots of the tetragonal phase LLZO (0 wt.% Al2O3) could be resolved into bulk, grain boundary and electrode contributions.
In our case, it is considered that at the Al content higher than 1.5 wt.%, Al doping enhanced the sinterability of LLZO which reduced the number of grain boundaries.
The reduction of grain boundaries lowered the grain boundary resistance, resulting in the lack of clear semicircle.
The total (bulk + grain boundary) conductivities of various Al dopants samples derived from the Nyquist plots were presented in Fig. 3 (b).

ADAMS software can only define a number of seeds during the simulation analysis of seed metering, but it cannot show the random motion of groups of seed and the relationship between seed and seed metering device and between the seeds.
For easy simulation calculation analysis, maize seed is simplified as ball-like grain.
For the difference between ball-like model and actual shape of maize grain, simulation procedure is the approximate result.
“m” is the quality of each grain.
When each maize grain reaches the relative stable position, contact force is generated by the press between grains.

Within, the TMAZ zone, the grain structure is partially recrystallised and the resulting microstructure is quite heterogeneous (Fig. 3).
The advancing side, corresponding to the weld side for which the welding and the rotation speeds are in phase, presents an abrupt microstructure change with a rotation of 90° of the parent metal grain structure.
On the retreating side, the microstructure transition is smoother and the grain structure is coarser.
On this side, a progressive recrystallisation with grain refinement is observed till the weld centre.
T8 as welded condition Fig. 3: TMAZs grain structure - left: advancing side - right: retreating side T8 as welded condition Fig. 4: WN grain structure - left: advancing side -centre: WN - right: retreating side In term of microhardness (Fig. 5a and 5b), there is no variation through the weld thickness: upper, middle and lower profiles are similar.

The typical microstructure of the wire is austenitic with nanosized grains (Fig. 8).
The average grain size of the austenitic phase is about 71.3 nm.
The nucleation from austenitic to martensitic is possible because the austenitic grains are nanosized (~ 71 nm) and they are oriented almost the same as the crystal lattice between single grains.
Induced loading or stress on SMA wire enables that austenitic grains start to rotate and plate can grow over the austenitic grains.
Complex deformation by a combination of torsion and bending caused an increase in the number of dislocations and, thus, a higher density distribution of the martensitic plate on the microstructure.