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In Kopalinsky's work, the contact length was used to quantify several grinding parameters, including the contact area of wheel and workpiece, the size of the heat source and the size of the heat flux of rubbing for calculating the grinding temperatures, the size of a set of active grains on the wheel in contact with the workpiece simultaneously in grinding and the time it took for the set to enter the contact region, the number of active cutting edges in the grinding contact area and the number of active rubbing points in the grinding contact area, and the contact time of individual active cutting grains with the workpiece, which demonstrated the importance of the contact length in the analysis of grinding processes.
And consequently the number of active cutting edges in the grinding contact area becomes 26 instead of 14.
Table 2 Comparison of the results based on different contact length models x based on lc, Eq.(1) y based on lg, Formula (1a) x/y Contact length 3.49 mm 1.88 mm 1.855 Contact area 10.5 mm 2 5.64 mm 2 1.855 Number of active edges 26 14 1.855 Maximum grinding temperature [16] ( ) cw w we lckv av T 1Re2.1 max         = ρ ( ) gw w we lckv av T 1Re2.1 max         = ρ 0.734 Conditions used in the analysis [18]: Workpiece martial: En9; Grinding wheel: WA46J with diameter ds of 177 mm; Depth of cut ae: 0.02 mm; Width of cut b: 3 mm: Wheel speed vs: 40 m/s; Workpiece speed vw: 0.5 m/s; Fn': 10 N/mm; Ks: 6.16 10-6 mm2/N; Kw: 1.36 10-6 mm2/N: Rr = 9 Figure 5 is an overview of the contours of rc-g covering a full range of grinding conditions, from fine grinding, shallow grinding, creep-feed grinding to high speed grinding (i.e. q is from 50 to 10000 and ae is from 0.001 to 50 mm).
In summary, an increase of grinding wheel wear and dullness during grinding processes means not only an increase in the area of the wear flats on its grains, an increase in the negative rake angle of the cutting edges as highlighted by Kopalinsky [18], but also a decrease in the real contact length.

The intensity and number of diffraction peaks mainly depend on the amount of corresponding phases.
The band positions and number of absorption peaks are depending on crystalline structure and chemical composition.
The number of peaks in the emission spectrum represents the wavelength of emission.
High frequency semi-circle corresponds to grain resistance (Rg) and low frequency semi-circle corresponds to grain boundary resistance (Rgb).
FTIR spectra depict the band positions and numbers of absorption peaks are depending on the crystalline structure and chemical composition.

The number and orientation of shear planes depend primarily on the number and the concentration of the oxygen vacancies.
With a radius of the Ti4+-ion in the titanium oxides of 0,61 Å (1 Å equals 10 nm) and a co-ordination number of 6 [16] besides Cr3+ primarily (Al, CO, Fe, Nb, Ni, Mn, Mo, Sn, Ta, V, W, Zr) - cations of different valence come into consideration.
The approach of obtaining coating systems of Andersson-type phase content by mixing two oxide ceramics in the plasma requires knowledge about the grain size of the powders being used.
Therefore the SPS process seems to be suitable particularly to mix a larger number of oxide ceramic systems in the plasma and to examine the resulting phase content concerning its suitability regarding the requirements.
Birringer: Estimating Grain-Size Distributions in #anocrystalline Materials from X-ray Diffraction Profile Analysis, Phil.

Introduction Straw is what’s left over when grains, such as wheat, rice, and barley, are harvested.
First, in areas of grain production, straw is inexpensive.
And more importantly, because straw is now as the waste material from grain production, in many areas in China straw is still burned in fields, producing significant air pollution [1] and increasing the risk of accidents of aircraft and vehicle on highways.
And the dampness or moisture damage in buildings originating from, for example, insufficient ventilation or leaking roofs, with subsequent microbial growth in building materials, has been associated with a number of health effects.

It is indicates the number of lithium complex oxides that react immediately with CO2 at temperatures ranging from the ambient temperature to high temperatures.
The reaction products were board-like powder particles comprising many grains.
The morphology of the grains differed from the degree of reaction and the size of the grains increased as the degree of reaction increased.

Thus, the change in transparency of films prepared by using acetylacetone is related to the effect of acetylacetone on the grain growth.
As discussed above, the addition of acetylacetone limits the grain and crystal growth, leading to homogeneously dispersed crystalline nanoparticles no strongly influenced by the annealing temperature.
The number of layers also diminish the resistivity of films due to the increase in thickness.
The homogeneity of film and small grain size allows an elevated optical transmittance.

Grinding speed, depth of cut, feed rate, and wheel properties, such as abrasive material and abrasive grain size, are the dominant parameters for the ball grinding process, as shown in Fig. 1.
As mentioned, the main ball grinding parameters having significant effects on surface roughness are grinding speed, depth of cut, feed, wheel properties, such as abrasive material and abrasive grain size, etc.
Consequently, tool material of the grinder ball with the diameter of 1.5 mm and grain size no. of 150, revolution of the spindle speed, depth of grinding, feed, and stepover were selected as five experimental factors (parameters) and designated as factors A to E (Table 1) for ball grinding in this research.
The S/N ratio, η, is defined by the following equation [5],       −= −= ∑= n i iy n stic characteri quality square mean 1 2 10 10 1 log10) (log10η (1) iy : observations of the quality characteristic under different noise conditions n: number of experiment After the S/N ratio from the experimental data of each L18 orthogonal array was calculated, then the main effect of each factor was determined by using the analysis of variance (ANOVA) technique and the F ratio test [5].

In addition to the alloying concept and deformation temperature (both effecting SFE), grain size and even local texture play an important role [13,17].
The TWIP steel in its as-received condition is characterized by a mean grain size of ~ 2 µm and features high dislocation density and a low fraction of twins [11].
Figure 2: a) EBSD grain map and b) TEM bright-field image depicting the microstructure of the as-received TWIP steel [15].
Based on the number of points depicted in Fig. 4, the findings presented in this study indicate clear trends for the HCF behavior, but of course more tests are needed for statistical evaluation of the results.

The blades used are three in number fixed appropriately with good joining technique / integrated in one piece to withstand the stress of the process.
The image clearly indicates that it is a polycrystalline material due to the impressions of grain boundaries.
Grain boundaries are observed, and the brighter region is the Al element.
The grain growth is hindered by the particulate which obstructs its further growth.

Investigated material Figure 1: Initial microstructure of Ti-6Al-4V The microstructure of Ti-6Al-4V at room temperature consists of hexagonal closed packed (hcp) αTi grains and a dispersion of body-centered cubic (bcc) βTi.
The two phase microstructure is visualized in Figure 1, where the αTi grains appear bright and the βTi grains dark.
The two phases are further responsible for the beneficial characteristics of high specific strength and microstructural stability at elevated temperatures as well as a large number of deformation mechanisms which influence the mechanical behavior of the material [12].