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Barkhausen noise, first of all, consists, in a nutshell, of gradual alterations of magnetization of a metallic ferromagnetic material that represent sudden overcomings (jumps) of obstacles (defects, non-metallic composites/aggregations, or as in our case, which we are most concerned of, accumulated distortions/disturbances that are usually caused by cold work-hardening processes (plastic deformation)) of the magnetic walls (Bloch) that are interposed between magnetic bipolars that form magnetic domains inside the grains of the materials.
The greater the amount of the containing defects and distortions inside the crystal grid of the material, the greater the minimum threshold power of the field needed to force the magnetic bipolars of the domains to rotate and therefore the Bloch walls to move, hence the greater the number of the jumps that may occur.
The Barkhausen noise analysis equipment arrangements, in short, consisted of an electromagnet that produced the magnetic field, a spool wrapped around its core in order to serve as an indicator of the proper conjunction between the surface of the samples and the censor, a second spool containing a ferritic cylinder in its centre, positioned between the two far ends of the electromagnet, that serves as the receiver/censor, an AC generator and DAC data collecting card that is connected to a PC, receives, amplifies, processes the input of the censor and gives us measurements: the counts (number of jumps of the Bloch walls occurred at a given voltage threshold), the power of the signal of the BHN (rms) and a qualitative indication of the magnetic permeability of the samples.
First of all, as expected, we ascertained the increase of the number of jumps of the magnetic Bloch walls (counts) as the hardness increased (resulting from the increase in grade of cold work-hardening).

The numbers of the polishing laminas is 84 and it is a height of 15mm.
It is founded by the experiments that the elasticity of abrasive tool has some connection with the numbers of the grit and the polishing laminas.
Small is the grain size of the abrasive tool, flexible is the lamina.
With increasing the numbers of laminas, the flexibility of the abrasive tool steady decline.

Introduction During the production and storage of SRM(solid rocket motor),propellant grain is under various loads and the defects such as crack and debonding may occur[1].
a．Hilditch b．Rosenfeld c．Zhang d．Deutsch Fig. 3 Thinning results by different thinning methods Hilditch thinning algorithm took the longest time ,and the most number of iterations.
Rosenfeld thinning algorithm took the shortest time ,and the most number of iterations.
The number of iterations of Deutsch thinning algorithm is one more than Rosenfeld thinning algorithm, and took triple time.

For polycrystalline Si3N4 films non-Gaussian depth profiles and strongly time dependent diffusivities are observed, which have their reason in the presence of intrinsic traps with negligible dissociation, presumably located at the grain boundaries.
We used the following initial concentrations at t = 0: [1HR]0 = 5 x 10 26 atoms/m 3 is the hydrogen concentration, [1H]0 = 1.3 x 10 24 atoms/m3 is the concentration of free hydrogen which is formed for a constant number of given traps [R]0 = R0 = 5 x 10 25 atoms/m 3.
We tentatively attribute these trapping centers to be present at the grain boundaries.
Due to the crystallization process the number of dangling bonds in the bulk decreases drastically, making the trapping mechanism of the amorphous state ineffective.

The application of slotted liner holds true to extract oil in the horizontal and high-angle well which is the grains of sand’s diameter is bigger than the 0.15 to 0.3mm.The design of construction is up to the mustard construction under the well.
(1) The number of straight wires on the outside wall of the screen-cut tube is 6.25—6.5 times of the number of bars when the outside diameter of longitudinal seam screens is the same as that of wire wrapped screen, the section of triangular straight wires is the same as that of the bar in shape, and the cross-sectional area of single wire is equal.
In this way, the screens, with even gaps, have good sand control efficiency for sand grains of 0.15-0.3mm in diameter.

After low level cyclic loading, Brinson et al. [9] show that the equiatomic Ni-Ti material reveals the presence of residual martensite in some grains.
This result indicates that the critical stress for the including martensite decreases with the number of cycles of Ni-Ti superelastic alloy.
Fig. 3 shows the evolution of the residual strain with the number of cycles.
This figure indicates that the residual strain increases progressively in the first ten cycles and becomes more stable with the increase in the number of cycles.
Moreover, Brinson et al. [9] have indicated that a small amount of residual martensite remains after each cycle and accumulates with the number of cycles.

It is probable that a sol-gel spin coating process at 200 °C produced dense, irregularly shaped Bi2O3 grains.
With metal ions doped into Bi2O3, the particle size and grain shape can be improved while the structure can be stabilized.
In JCPDS file number 81-0563 [20], 10.25 Å is reported after annealing the film, and the results of XRD are in good agreement.
The figure shows several dense morphologies along with fine-grained microstructures.
It is likely that Bi2O3 grains were formed in dense irregular shapes using a sol-gel spin coating technique at 200 °C.

The number of dredged silt poured from coastal areas was more than 30 millions cubic meters in 1997, and the number rapidly increased to 100 millions cubic meters at the beginning of the century.
Their grain diameter was less than 0.9 mm and the modulus of fineness was 0.8.
Number and place them under a shaded area to dry them naturally (about two days and two nights).
Two kinds of waste residues in the composite sea mud have different water volume demands because they have different grain sizes.
Table 3 The liquid-plastic limit and plastic index of sea soil addition of iron tailing or fly ash Number of Sample WL (%) Wp (%) Ip Number of Sample WL (%) Wp (%) Ip H100 45.4 23.0 22.4 H100 45.4 23.0 22.4 H95F05 43.6 23.6 20.0 H95T05 45.2 22.0 23.2 H90F10 47.5 22.5 25.0 H90T10 43.4 22.1 21.3 H85F15 45.9 22.2 23.7 － － － － H80Ｆ20 43.8 24.2 19.6 H80T20 40.0 18.6 21.4 Based on the above analysis, reducing the volume of blending water during blank molding lessens scumming degree of sea mud sintered brick to a certain degree.

Characteristics of gas emission in Yongshanqiao Mining Area Coal Mine Yongshan Yangou Xiancha Number of samples 79 21 33 Average elevation (m) -257 -231 -294 Mean value of Q (m3/min) 3.452 2.271 2.213 Mean value of q (m3/t) 26.509 14.312 14.644 Trend value (-250m elevation) of Q (m3/min) 3.243 2.550 1.840 Trend value (-250m elevation) of q (m3/t) 25.532 16.170 12.707 Note: Q: Absolute Gas Emission Rate; q: Relative Gas Emission Rate Along the dip of coal seam, Fig. 2, 3, 4 are the statistical information about gas emission of representative mining districts at Xiancha Coal Mine, Yangou Coal Mine and Yongshan Coal Mine.
Table 2 shows the noticeably increased likelihood of coal and gas outburst from east to west according to the data of the increased outburst number, the increased maximum value of outburst coal and gas, and the increased number of super large outburst.
Characteristics of coal and gas outburst in Yongshanqiao Mining Area Coal Mine Yongshan Yangou Xiancha Number of outburst 98 47 13 Mean value of outburst coal (t) 206 248 91 Maximum value of outburst coal (t) 3988 2400 587 Maximum value of outburst gas (1×104 m3) 16.7 15 1.5 Maximum elevation of outburst (m) +60 -60 -35 Number of super large outburst 4 1 0 Table 3, 4 are the statistical information about coal and gas outburst of Xiancha Coal Mine and Yongshan Coal Mine in different mining depths.
At the same time, the grain size of rock in the coal bearing stages tend to be smaller from east to west.
The trend of thicker coal bearing stages and smaller grain size of rock is more conducive to the preservation of gas [5].

The grain accumulation and distribution theory is studied by the predecessor.
Considering the large number of the aggregates, a conversion program to extract the model data from Matlab to Ansys is also established.
The number of each level particle is w1, w2 … wn .
Considering the large number of the aggregates and their irregular distribution, it is unpractical to build the model by GUI operation in Ansys.