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The result shows that the influence of density-grain degree coupling on saturation loess liquefaction has a feature of segmentation, plastic index plays the main role for loose loess, whereas density is the main control factor to dense loess; Moreover, the influence of density-grain degree coupling on saturated loess liquefaction controlled by cyclic numbers of the vibration, plastic index plays the leading role while the vibration times is small, while the more vibration times, the bigger density and higher strength of liquefaction.
Thus, for the loess liquefaction, grain degree and density is the most important influence factors.
In order to study the effects to saturation loess liquefaction by density and grain degree respectively, the relationship between the initial void ratio (e) , plastic index (Ip) and the liquefaction stress ratio (σd/2σ0′) under different seismic intensity is obtained though a large number of dynamic triaxial experiments of the disturbed loess samples, which as shown in figure 3[6].
To sum up, based on summarize of the experimental results which are shown above, the influence of density-grain degree coupling on saturation loess liquefaction could be divided into the following stages, shows in Tab.2 Tab.2 The segmentation of density-grain degree coupling on saturation typical loess liquefaction e Ip Ip is smaller Ip is larger e is smaller The liquefaction stress controlled by e The liquefaction stress controlled by e & Ip, but the largest e is larger The liquefaction stress controlled by e & Ip, but the smallest The liquefaction stress controlled by Ip Secondly, the cyclic numbers of vibration has a fine effect on the density-grain degree coupling.
(3) The main property indexes of loess liquefaction influenced by cyclic numbers of the vibration, plastic index plays the leading role while vibration time is small.

The aim of this research is to determine the hardness of the Schizolobium amazonicum Wood in directions parallel and normal to the grains.
For each direction in relation to the grain (parallel and normal) were made 6 specimens, according to ABNT NBR 7190: 1997 [10].
(2) Results and Discussions Table 1 shows the average values of hardness parallel and hardness normal to the grain (Xm), standard deviation (SD), variation coefficient (CV) and the number of specimens (x) of Schizolobium amazonicum Wood.
Average values of hardness parallel and hardness normal to the grain of Schizolobium amazonicum Wood [MPa].
Hardness fH0 fH90 x 6 6 Xm 27 15 Sd 6 4 VC [%] 22 25 The average hardness of the Schizolobium amazonicum Wood in the direction parallel to the grain equal to 27 MPa was higher than that determined in the direction perpendicular to grain, this is due to the anatomical composition of wood that ensures greater strengths to wood in the axial direction relative to the grain [14, 15].

In order to locate and segment the image of grain bags in the granary reserves, and making full use of the spatial location information of grain bags, a threshold method is proposed base on two-dimensional Fisher criterion.
It is of great practical significance for upgrading the supervision level of grain management.
(3) where, is the integer function, let K that is usually an odd number denote the neighborhood width of pixel (x, y).
In the actual scene of grain bags reserves, the grain bags had the characteristics of relatively consistent, while the gray value of each bag region are concentrated and well-distributed.
In terms of the segmentation results, the traditional 1D Fisher method can segment each grain bag region, but that approach had some segmentation error, caused loss of some grain bag regions.

First, the exponent of the inverse grain size is given by p = 2.
The alloy had an initial grain size of ~1.8 μm after annealing at 473 K for 1 h and was refined by ECAP processing for 8 passes to have a mean linear grain size of ~0.8 μm [8].
It should be noted that the tensile axis is vertical in the micrograph in Fig. 1(b) and the grains appearing white are the Zn-rich grains and the grains appearing dark are Al-rich grains.
The disk samples with a diameter of ~10 mm and a thickness of ~0.80 mm were processed under a pressure of 6.0 GPa at 1 rpm for total numbers of 4 and 5 turns in a constant rotational direction.
There is a reasonably homogeneous distribution of Zn and Al grains with an average linear intercept grain size of ~350 nm.

The increase in vibration accelerates the grain to fill the empty space between the grains.
In general, the soil grains are distinguished into: gravel, sand, silt and clay, which are commonly found in natural soil deposits in the form of mixed grains.
Amplitude is the maximum displacement, while the frequency is the number of vibrations per second.
During experiment the movement of sand grains recorded.
This was due to the greater frequency of vibration, the faster of grain movement to fill the empty space between the grains so that, the landslide field is wider.

For the films fired at 750�, the needle-shaped grains (a-axis grains) were very fine and pores were frequently observed.
In addition, the a-axis grains disappeared as the firing temperature was increased to 775�, suggesting that the grains mainly consisted of c-axis grains.
It then decreased drastically to 54 A/cm-width with increasing number of coatings.
The film thickness increased almost linearly with increasing number of coatings up to 5 times.
XRD patterns of the films with the number of coatings

Overall，the average ferrite grain sizes in the three tested rebar are fine, which have fine grained strengthened effect and are contribute to improve strength and plasticity.
Ferrite content /% Pearlite content /% Bainite content /% Ferrite grain size /um Ferrite grain grade /grade 1# 59.3 40.7 / 8.5 10.4 2# 49.1 26.8 24.1 8.6 10.6 3# 56.7 36.6 6.7 8.6 10.6 Table 3 Quantitative analysis results of microstructure and ferrite grain size for different microalloyed rebars.
According to the test results of precipitates, a large number of V(CN) and Nb (CN) precipitates with size of 5～30nm are formed and distributed on ferrite matrix, grain boundary and dislocation lines.
The cleavage fracture is composed of a large number of cleavage plane with the size being equivalent of the grain size.
Becauce when crack grow and propagate, it would go through a certain number of parallel cleavage plane with different orientation,which result in grain boundaries become obstacles to crack propagation, grain size effect crack propagation that is the cleavage plane size increases with grain size increasing and grain boundaries crossed by crack propagation is lesser, therefore, the crack easily propagate and propagation rate is also faster, which easily lead to cleavage brittleness fracture.

This is the very simple processing that only bar-shaped material is twisted, and then torsion worked material is twisted in the opposite direction for the number of times.
Experimental Results 3.1 Control of grain size Fig.2 shows that the annealing time versus the grain size of the material to control a grain size.
The grain growth stopped though grains grew soon after annealing the material, once again grew rapidly.
The grain size of the material under test was 15μm.
And it is found that grains extended in the direction of it.

The tensile strength, compressive strength and the elongation to failure of the fine-grained AZ31 are enhanced due to the reduction of grain size.
Reduction of the mean grain size is also expected to promote super-plastic deformation at higher strain rates and/or lower temperature than those conventionally used for large grain size materials.
The number of ECAP passes was six.
The structure is an equaled grains with a grain size of about 120µm.The sample subjected to six passes has a homogeneous, fine-grained microstructure with a grain size of about 8µm, as it can be seen in Fig. 1b.
A fine-grained Mg alloy AZ31 was obtained by ECAP.

In grinding process, the point that enables to become a cutting-edge is only the highest point of grains.
Therefore, it is thought that the grains are maintained on the working surface, and then, the cutting-edge is generated on the top of those grains.
Since the grains are maintained, with progression of dressing, internal grains are exposed to the peripheral surface.
In other words, in case of less number of spark-out, since the grains damaged with dressing remain on the working surface, the shedding tends to occur with grinding.
This indicates that there is the critical value for the spark-out number in dressing.