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Here, GBs denote interfaces between UNCD grains and those between UNCD grains and the a-C matrix.
Since the disappearance of diamond grains brings about the disappearance of a huge number of GBs, the sudden decrease in the electrical conductivity should be attributed to the disappearance of GBs.
From the XRD measurement, it was found that the sudden decrease in the electrical conductivity exactly coincides with the disappearance of diamond grains in the films, and therefore, with the disappearance of a huge number of GBs.
From the XRD measurement, it was found that the sudden decrease in the electrical conductivity just coincides with the disappearance of diamond grains in the films, in other words, with the extinction of a huge number of grain boundaries.
A huge number of GBs that is the distinctive structure of UNCD/a-C:H films should play a significant role in the nitrogen doping specific to UNCD/a-C:H.

The key issue on the use of copper is the formation of copper oxide limiting the number of its functional application.
Few reports figured out that small grain size copper has low oxidation resistance as compared to big grain size copper due to small grain size has larger grain boundaries which has high defect density promoting to higher diffusion rate of atoms [2,5].
Effect of Grain Size.
Once the oxide grains was formed which was smaller than the initial grain of fresh sample, it will create higher formation of grain boundaries.
Napolitano, Measurement of ASTM grain size number, Material Science and Engineering, Iowa State University, available online on http://mse. iastate. edu

The synthesis of ultrafine-grained (UFG) materials is very attractive because small grains lead to excellent creep properties including superplastic ductility at elevated temperatures.
However, the maps have complications for construction due to the difficulties of estimating the curved field boundaries which require special calculation procedures to prepare a very large number of datum points in stress-temperature space.
This grain size was selected because, although the creep data came from the earlier published results demonstrating successful grain refinement of the high-purity Al from 1 mm to 1.3 µm through ECAP for 4 passes at room temperature, there is grain growth during tensile testing at 473 K [20].
Principles of superplasticity in ultrafine-grained materials, J.
Langdon, Deformation mechanism maps based on grain size, Metall.

A novel fault localization technique based on fine grained slicing spectrum is proposed in this paper, which can increase the efficiency of fault localization.
This technique analyzes the reliance information under fine grained level, and selects the check points which are prone to be faulty, and the faulty statements is located according to the suspicious result.
TotalPassed is the number of total passed executions, and TotalFailed is the number of total failed executions.
We select a number of target programs as the experiment target.
The method proposed in the paper will locate the faulty statements according to the order of suspiciousness, thus, the real effect can be valued by the number of statements called by the executions, that is: Scale= s|P| where s is the number of statements called by the real faults according to the suspiciousness, |P| is the number of statements contained in the program P. the smaller the value of Scale is, the less the number of statements that needed to locate the faults, and the higher the efficiency is.

Since creep resistance is influenced by the grain size, it increases due to the fine-grained structure as a result of recrystallization during extrusion.
Grains near precipitations show even smaller grain sizes (< 10 µm).
Number of cycles to fracture reaches the ones of WE43 between stress amplitudes of 120 and 140 MPa.
Using S-N data of AZ31 -1- all the RE containing alloys show significantly lower number of cycles to fracture.
Mg10Gd1Nd at 130 MPa reached cycle numbers between 72,000 and 130,000, see Fig. 4c.

Grinding wheel consists of abrasive grains, bond and pore, and each abrasive grain is connected by bond-bridges.
It is considered that the contact stiffness of the grinding wheel in grinding operation depends on the number of the abrasive grain in contact with the workpiece.
If the support stiffness of single abrasive grain kgs and the number of abrasive grains in contact area can be obtained, the theoretical contact stiffness of the grinding wheel can be calculated by product of these values [2][3].
The number of abrasive grains in contact area can be obtained by multiplying a contact area between grinding wheel and workpiece A by abrasive grain density ng.
Here, the abrasive grain density ng for dressing lead 0.1, 0.5 and 1.0 mm/rev were used as 2.2, 1.6 and 2.0 grains/mm2.

The average αp grain size is about 25 µm and the former β grains have a mean diameter of 60 µm.
The rotation angle ω around a given axis R defines the rotation which allows to pass from the reference frame of an αp grain to that of an αs grain.
The illustrative example presented in fig. 6a shows an isolated β grain and the adjacent αp grains (numbered from 1 to 7).
The αp neighbour which has the c-axis, the closest to a <110>β direction is number 5.
Similar results were observed for other isolated β grains.

Introduction The Nb solute atoms and precipitates pin the austenite grain boundaries and reduce the recrystallisation and grain growth rates, which leads to grain refinement and improved mechanical properties.
Nb(C,N) precipitates were shown to pin the grain boundaries stronger than Nb solute atoms [2 - 4].
To obtain the austenite grain size (equivalent circle diameter) distributions, 800-1000 grains were imaged using Leica DMRM optical microscope.
With a decrease in austenitising temperature, the Nb content in the austenite matrix, the Nb cluster size and number density and the Nb-C cluster number density all decreased, although the Nb-rich particle number density increased (Table 2).
Table 2 Summary of the parameters for Nb-rich precipitates and Nb-containing clusters Re-heating temperature [°C] 1100 1250 Deformation temperature [°C] 1075 975 1075 975 Nb in the matrix [wt %] 0.002 0.005 0.016 0.015 Nb clusters Maximum cluster size [number of atoms] 10 8 12 16 Maximum Guinier radius [nm] 2.1 1.4 1.6 1.7 Number density [×105 mm-3] 1.60 2.15 3.19 3.74 Nb-C clusters Maximum cluster size [number of atoms] 53 72 92 53 Maximum Guinier radius [nm] 3.0 3.6 4.1 3.0 Number density [×105 mm-3] 0.20 2.0 4.3 7.0 Nb-rich particles Average diameter (20-70 nm range) [nm] 26 22 29 29 Number density (20-70 nm range) [mm-3] 3.13 12.06 2.05 2.75 Austenite grain size [mm] 10 6 9 Partial recrystal.

Applying forced melt flow results in the formation of small grains in the centre part.
Their large spectrum in colors represents very different orientations of the grains.
To classify the flow type for different rotational frequencies the magnetic Taylor number is used.
This number denotes the ratio of Lorenz forces and viscous forces in the melt and can be calculated as 2 42 pt ru © ©©©© ?
If the height of the melt column is larger than its diameter, the critical Taylor number converges to a value of about 3700.

Deformation structure evolution and grain refinement.
Black lines represent high angle grain boundaries (>15 o) and white lines low angle grain boundaries (2-15 o ).
After 8 CFAE passes (εvm ~ 5.3) the average spacing of HABs, or grain width, was at a submicron scale and in the most regions groups of pancake-like submicorn grains were seen to have formed within the lamellar structure.
Following deformation, crystallographic textures of samples processed to different numbers of CFAE passes were determined by EBSD.
CFAE processing of AA1050 sheet samples was successfully carried out to various total numbers of passes and a uniform and nearly equaixed UFG structure was achieved after 10 CFAE cycles, or at an equivalent strain of 6.6.