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Investigations were determined by the small number of operating hours and the fact that the shaft was not produced by the manufacturer of the machine.
In such areas, fatigue cracking was initiated following the action of alternant loading due to the plastic deformation in certain ferritic grains oriented favorable to sliding.
In conclusion, in the ferritic areas from the surface, in a small number of grains, sliding strips were formed, with higher densities as the number of cycles increased and those grains became more and more strain hardened.
Thus, after a certain number of cycles, the material hardened so much that it did not allowed any new plastic deformations, forming thus submicroscopic cracks.

The machinability of SiC/Graphite sintered by PAS in 1500C was good because the continuous weak microstructure played a crucial role in the machining process, including a lot of weak interface between the grains of SiC and graphite partials and nearly 20vol% pores in the composite ceramics.
In such case, a number of research work were carried out to promote their machinability by adjusting the microstructure.
The machinable SiC/C(graphite) composite ceramics is one of the typical weak interface fibrillary structures, and the grain boundary of flake graphite may be attributed to hinder crack growth.
Because the fracture occur along the direction of weak graphite grain boundary, it can induce the crack deflection or exfoliation on shear direction, so the toughness can be improved and inhibit brittle fracture[3,4].
Though 20vol% flake graphite with 35μm mean size was adding to SiC matrix, continuous weak phase and weak interface were not produced because the size of graphite is too large and cannot be distributed homogeneously between SiC grains.

It can be observed in Fig.2 that the crystal shapes of the diamond film are regular and the grain sizes are uniform.
The shape and size of the grains in the edge are similar to those in the center.
The Raman peaks at ~1332cm-1 on both sides shift to higher wave numbers and the value increases along radial direction towards the edge.
The size of the grains at the original surface Fig.4 Raman spectra of original surface and final surface is very small and there are quantities of defects such as grain boundary and vacancy which will cause high tensile stress.
When entering the growing stage from the nucleation stage, the grains of the diamond film grow up and the quantity of grain boundary and vacancy decreases, therefore the tensile stress caused by boundary and vacancy reduces correspondingly.

A number of approaches have been tried to prepare HA–ZrO2 composites containing fraction of ZrO2 from 2 vol% to 40 vol% [5].
During the sintering process, the originally grain size zirconia of about 30 μm ( actually arranged of nanometer grain size ) broken into single grain (Fig. 3-a and 3-b).
This single grain serves as crack deflection on HA matrix (Fig. 3-d), in contrast, HA crack without deflection (Fig. 3-c).
During the sintering process, the originally grain size ZrO2 of about 30 μm (actually arranged of nanometer grain size) broken into single grain.
This single grain serves as crack deflection on HA-ZrO2 composites, in contrast, dense HA crack without deflection.

Due to the compositional variations, each La-Mg based alloy showed a singular grain structure.
These alloys exhibit a more refined grain structure.
The LaMg2Ni9 alloy, on the other hand, showed a distinct, almost columnar, grain structure.
N is the number of independent measurements in the phase.
The standard LaNi5 alloy, showed a microstructure with large equiaxial grains, whereas the LaMg2Ni9 alloy showed a distinct, almost columnar grain structure.

During these attempts the system renders the user’s input and hands it to a respective database trigger that applies the following formula to determine the IF measures of his self-confidence: , (3) where “t1” is the number of true answers in the first attempt, “fm”– the number of false answers in the last (m-th) attempt, n – the total number of blank fields in the question.
Level of Grain of the intuitionistic fuzzy data warehouse.
The grain in data warehousing determines the level of detail of a fact table.
The grain of the fact table is a student’s final submission of answers to a question.
Then B has to be on the same level of grain as A.

This thesis, based on the discrete element theory and by means of two-dimension grain flow simulation software PFC2D, considers three oil wells with unconsolidated sandstone in terms of their cementing strengths .
Shengli Oil field has to conduct sandcontrol performance more than 4000 wells a year, and the number tends to increase.
Figure 1: damaged bonding figure of formation grain after forcing Well Yong 8-7 by high pressure In this section, the results obtained are shown.
Figure 2: damaged bonding figure of formation grain after forcing Well M19-12 by high pressure In this section, the results obtained are shown.
Figure 3: damaged bonding figure of formation grain after forcing Well G114-6 by high pressure Simulation above shows that the layer shape after high-pressure squeeze packing of the unconsolidated sandstone oil reservoir is rather complicated, with sensible error as compared with existing calculation pattern.

Because of the microbes attached on carbon grain surface exist in forms of biological film or bacteria micelle, the biofilm should be peeling off from the carbon surface, and preparation into bacteria levitation liquid.
It is generally using the blood count plate to determine that the number of bacteria living bacterium.
Due to the volume of counting chamber is certain (0.1 mm3), so according to the bacteria number inside the counter dial we can calculate the bacteria number in the sample.
From the change of viable bacterial number, we can see the decrease viable bacterial number at the top of BAF is 6.67% to the bottom.
But the viable bacterial number more effectively reflects the number of activity microorganism in BAF.

Therefore, the grain growth at the interior of the layer holds preferred orientation from the bottom to top, thus forming the dendrites.
By contrast, grain growth at the surface of the layer does not depend on the orientation, thereby generating the cellular structure.
As illustrated in Fig. 6, a large number of dimples with various shape and size are distributed on the fracture surfaces, which indicates that the fracture characteristic of as-formed Ni60A samples is the ductile fracture behavior.
However, since the deformation at the grain boundaries was restrained, at a small strain, the fracture will occur along the grain boundaries.
Finally, a number of metal parts were produced using the LMDS setup.

Structure of intermetallic compound (I) consisted of radial grains.
The mean lateral size of radial grains was about 0.1 mm.
Acknowledgements The work was supported by the Czech Science Foundation - contract number 106/05/2115 and by the Academy of Sciences of the Czech Republic - number of the project AV0Z20410507.
Gust: Fundamentals of Grain and Interphase Boundary Diffusion (Ziegler Press, Stuttgart 1988)
Fig. 12 Grain boundary wetting in alloy E