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In addition, we found the strongest (119) peak of as-deposited thin films as the annealed temperature of 750℃ Introduction Bismuth-layer-ferroelectric-structured (BLFS) crystals have an anisotropic crystal structure consisting of bismuth oxide layers and pseudo perovskite blocks with the general formula (Bi2O2)2+–(Am-1BmO3m+t1) 2-, where A is a mono-, di-, or trivalent ion, B is a tetra-, penta-, or hexavalent ion (Ti4+, Nb5+, or W6+), and m is the number of BO6 octahedra in pseudo perovskite blocks [1-3].
In addition, grain size, electrical properties and surface roughness are greatly affected by annealing temperature under conventional furnace annealing [14-16].
After annealed, a type grain growth was observed.
As increasing annealed temperature, the size of the grains slightly increase and the porosities of film decrease.
The lower leaking current observed for the film annealed in different temperature may be attributed to probable differences in grain size density, and surface structure due to different in crystallization.

Large meandering river still has large sedimentation scale; point bar sand is the special product of meandering river, mainly in lateral accretion; the interlayer is in skewed distributions, with the general angle of less than 10 degrees; the convex bank accepts sedimentation whereas the concave bank accepts erosion is prone to form crevasse channel, crevasse sheet sand (or crevasse splay), oxbow lake or partially abandoned channel; the channel sand body mainly consists of sandstone, siltstone; the area is large, composing of a number of single point bar lateral erosion cutting contact form; the width of single point bar is generally above 500m, and the maximal width is up to 1000m; the thickness is between 3m and 7m, with relatively high permeability, generally between 0.3μm2 and 1.0μm2.
Fig.2 Bedding structure of point bar Fig.3 Lateral accretion interlayers of point bar Low Bending-straight Distributary Channel Sedimentary Model.Low bending distributary channel sand body is mainly featured by lateral accretion in the curved parts; the logging curve shows the fine positive rhythm of features of coarse grain downward and fine grain upward; the relatively straight part is featured by vertical accretion, the logging curve shows homogeneous massive bedding , with uniform grain, mainly consisting of fine-grained sandstone.

The densification of green pellets can broadly be envisaged to consist of two phases, reduction of the porosity and solid material annihilation of the pores due grain growth in the compacts during densification process [3].
Fig.3 allows to visualize the formation of grain in the center and on the surface of the pellet through the upper images which were detected by secondary electrons.
Densification rate is high at the beginning of the skhrinkage process, this is because the presence of large number of contact points.
When the temperature approaches 1300ºC the densification rate tends to become more slowly, due to decreased grain boundary, showing that most particles have been sintered.
The temperature increases and it contributes to the sintering of particles, but the rate of densification presents high in the process beginning and decreases with the formation and growth of grains in the hardened pellet.

Grains with 20 – 50 μm in diameter are β phase, and α phase precipitates in β phase.
Since crack initiation causes a decrease in the resonance frequency, a fatigue test was interrupted when the resonance frequency fell below 300 Hz or the number of cycles exceeded 1010 cycles.
Kagaya and Nakamura [4] conducted fatigue tests of Ti-22V-4Al subjected to the same heat treatment in this study and discussed the fatigue fracture mechanism of internal fracture; the initiation location of internal fatigue fracture could be a point in which adjoined grain boundary planes were inclined about 45° from the maximum principal stress direction, and cyclic loading could lead to the simultaneous slips of the grain boundaries.
Kariya, Effect of grain size and aging conditions on fatigue crack propagation behavior in beta Ti-22V-4Al alloy, Tetsu-to-Hagane 86 (2000) 769-776

In other words, the real erosion in engineering can be considered as a non-linear superposition process of a number of single-particle erosions with different impact angles and velocities [5].
By measuring morphological and mechanical parameters in the common worn area after each single-particle erosion, including indentation size and shape, surface hardness, grain size and distribution, it can be expected that the damage laws between in damaged surface by multiple particle erosions and by each single particle erosion is discovered [8, 9].
By comparing Fig. 8 (c-1) and (c-2) with Fig. 8 (c-4) and (c-5), we can know that grains on surface layer of the 90° erosion morphology are refined perpendicular to damage surface caused by normal press exerted by particle, while those of the 30° erosion morphology are elongated along damage surface in the direction of ploughing by particle.
Grain sizes in overlapping part are obviously smaller than in other parts by the two erosions, which is induced by the cumulative effects of erosion damage by the two erosions on this common worn area.
Acknowledgments This work was supported by the Natural Science Foundation of Hubei Province [grant number 2019CFB208]; and the PhD Start-up Fund of Jianghan University [grant number 1006-06640001].

Recrystallized SiC (R-SiC) can be formed by mixing comparatively course SiC powder having grain sizes on the order of 10 to several tens of mm with fine SiC powder which have grain sizes smaller than 1 mm, and then heating the resulting mixture to temperatures of more than 2000ºC.
Then, it is possible to form SiC porous material that has a continuous and evenly distributed pore structure by sintering and, grain growth.
The cycle was repeated 10 3 times giving due consideration to the number of times that regeneration actually occurs in motor vehicles.
The decreasing effect of the total number of particles of PM measured using the SMPS method is shown in Fig. 5.
The number of particles contained in the exhaust gas after passing through the re-crystallized SiC-DPF was nearly the same as that in the air.

The structure of IN 713LC and In 792-5A consisted of large γ grains with dendritic morphology, carbides and shrinkage pores up to 0.4 mm (IN 713LC) and 0.5 mm (IN 792- 5A) in diameter.
The average grain size determined by the linear intercept method was 4.2 mm (IN 713LC) and 3 mm (IN 792-5A).
Fig. 3 shows the fatigue life curves in the representation of the plastic strain amplitude εap at half life versus the number of cycles to fracture Nf.
For the given stress amplitude the number of cycles to fracture is reduced with increasing temperature.
Fig. 5 documents dislocation arrangement of a specimen cycled at 23 °C up to fracture (εa = 1.25 %, εap = 0.712 % at half life) in a grain oriented for single slip (S.A. = ]893[ ).

The broadened Mg2Ni peaks indicate refinement of the average grain size and storage of the stress in the grains [5].
The micrograph of the Zr0.3 alloy milled for 30 h displays a like amorphous characteristic, but the Zr0 alloy milled for 30 h exhibits a typical nanocrystalline structure with grain sizes of about 20 nm.
The discharge capacity of the MA Zr0 and Zr0.3 alloys as a function of the cycle number is illustrated in Fig.4, at a discharge current density of 100 mA/g.
Fig.4 Evolution of discharge capacity of alloys with cycle number:(a) Zr0 alloy; (b) Zr0.3 alloy The maximum discharge capacity of the MA alloys as a function of the milling time is plotted in Fig.5.
The capacity retaining rate (Sn) as a function of cycle number is plotted in Fig.6.

Table 1 Macroscopic Model Parameters of Strata Strata Numbers Model Size（mm） Permeability Coefficient（cm/s） Particle Diameter（mm） 1 8×4×4 1.4×10-2 0.1~0.25 2 16×8×8 7.7×10-2 0.25~0.5 3 32×16×16 3×10-1 0.5~1 4 64×32×32 1.2 1~2 5 150×75×75 5.2 2~5 Stratum 's Parameters( Skeleton/Packing) Normal/Tangential Stiffness 1×107N/m Coefficient of Internal Friction 1.25 Particle Density 2050 kg/m3 Bentonite Parameters( Skeleton/packing) Particle Diameter 60~190um Normal/Tangential Stiffness 0.47×105N/m/0.16×105N/m Coefficient of Internal Friction 0.5 Particle Density 1100 kg/m3 Wall Unit Normal/Tangential Stiffness 1×107 N/m Coefficient of Friction 0.5 Fluid Parameters Density 1000 kg/m3 Dynamic Viscous Coefficient of Fluid 1.0×10-3Pa.s Calculation Unit of Fluid 20×5×5 Pore Pressure 0.2MP Other Params Gravity 10.0m/s2 Time Step of DEM 1.1e-7s Time Step of CFD 5e-5s Table 2 Particle Meso-scale Model Parameters Table 3 Numerical Test Group Strata Numbers Particle Diameter
Fig. 8 Stratum 3 Fig. 9 Stratum 4 Fig. 10 Stratum 5 Contrast of numerical tests and laboratory experiments A total number of 45 groups of laboratory tests [4] are conducted in five different strata with nine kinds of slurry.
G—The effective grain size of slurry.
With respect to numerical experiments, a total number of 34 groups of tests in five different strata are conducted by computer.
The comparison between bore diameter of strata and effective grain size of slurry are adopted in laboratory tests while comparison between particle size of strata soil and grain size of slurry are employed in numerical simulation.

The La0.7Mg0.3Al0.3Mn0.4X0.5Ni3.8 (X= Co,Nb) alloy is composed mainly of the matrix phase and other phases in the grain boundaries.
The as-cast microstructures by SEM of the alloys with a typical grain structure are shown in Fig.1.
The cycle number dependence of discharge capacity of the alloys is illustrated in Fig. 4.
Figure 4 - Cycle number dependence of the discharge capacity of the alloys The activation capability was characterized by initial activation number.
The initial activation number was defined as the number of cycle required for attaining maximum discharge capacity through charge-discharge cycle.