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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.

We have reported in this paper, the effect of grain size in Nd0.6Sr0.4MnO3 .We have investigated the effect of grain size on metal-insulator transition and Curie temperature.
Variation of sintering temperature changes the grain size.
We have employed the Debye Scherer formula to calculate the grain size.
The grain surface contains large number of defects and magnetic spins become pinned there.
The reduction of grain size reduces TP and TC quite appreciably.

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.

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.

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.

The grain refining mechanism of the carbon grain refinement is currently under disputation [4, 5].
The twins usually traverse entire grain and stop at the grain boundary.
However, the twins are finer and number of twins is larger than that in AZ31 alloy.
As mentioned above, the newly formed grains expand into the as-cast matrix by grain growth and nucleation of further grains at the grain boundaries of the growing grains.
Nucleation of new grains at grain boundaries involves formation of subgrains at grain boundary regions [6, 7].

All the samples investigated in the present study show the presence of relatively large austenite grains, demonstrating that the number of active nucleation sites of austenite per unit volume is small.
Table 2 lists the average grain size, measured after applying DAAS, the average number of kish graphite per unit area, and the size of the larger eutectic cells.
In addition, there is a considerable number of primary (kish) graphite particles inside each austenite grain.
Table 2: Average grain size, average number of kish graphite and eutectic cells per unit area for samples A, B and C.
The nucleation of austenite appears to be independent from the prior precipitation of proeutectic graphite, as the density of kish graphite particles is much higher than the number of grains of austenite.

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].

It is generally accepted that β-sialon tend to develop into elongated grains, while α-sialon usually occurs in equiaxed grains.
However, some recent experimental results show that α-sialon with elongated grains can also be obtained by controlling the nucleation and grain growth properly and the toughness is improved considerably [5-8].
It is clear that increasing N2 pressure results in larger grains.
In the sample Yb1510-S2, most grains occur in elongated morphology and the average aspect ratio of the elongated grains is between 3 and 5.
But on the other hand, excessive addition of seeds results in a large number of α-sialon nuclei which have not adequate space and sufficient materials to develop into elongated grains.

Introduction Recently, industrial products have become increasingly smaller and a greater number of functions are required each year.
As a result, abrasive grains are concentrated and fixed around the tool tip.
The behavior of abrasive grains is then observed.
In order to obtain a more detailed understanding of the behavior of abrasive grains, the density of abrasive grains is less than in the case of the machining and the larger abrasive grains are used.
When the applied voltage is low, the electrophoretic force acting on abrasive grains is small, and abrasive grains cannot closely approach the micro tool (Fig. 6(b)).