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For this reason a considerable number of studies can be found in literature on this subject.
The dark grains on the Fig. 2 correspond to pearlite grains, and the light grains to ferrite.
No fluctuations of the temperature values were found with the interaction of ferrite and pearlite grains.
This was due to the interaction of soft ferrite grains and hard pearlite grains with the cutting edge and the rake face.
When a pearlite grain incised with the tool, a peak value of contact pressure was obtained.

WalterTM 25mm diameter PCD end mills with 5μm and 25μm tool grain size (tool type: ZDGT 150408 R-85) were used in the milling tests.
Table 1 Experiments arrangement for the effect of cutting parameters and tool geometries on cutting temperature (for the no heat treated workpiece, volume fraction=20%, tool grain size=25μm) Test number Cuting speed v [m/min] Feed rate fz [mm/tooth] Radial depth of cut aw [mm] Rake g [º] Tool nose radius R [mm] Average particle size S1 [μm] No.1 600 0.25 0.5 0 0.8 7 No.2 900 0.25 0.5 0 0.8 7 No.3 1200 0.25 0.5 0 0.8 7 No.4 1200 0.15 0.5 0 0.8 7 No.5 1200 0.08 0.5 0 0.8 7 No.6 1200 0.25 1.5 0 0.8 7 No.7 1200 0.25 3 0 0.8 7 No.8 1200 0.25 0.5 -8 0.8 3.5 No.9 1200 0.25 0.5 8 0.8 3.5 No.10 1200 0.25 0.5 0 0.8 3.5 No.11 1200 0.25 0.5 0 2.0 3.5 Table 2 Experiments arrangement for the effect of workpiece and tool characteristics on cutting temperature (v=1200m/min, fz=0.25mm/tooth, aw=0.5mm, g=0º, R=0.8mm) Test number Volume fraction [%] Average particle size S1 [μm] Tool grain size S2 [μm] Heat treating and cooling condition No.12 20 3.5 25 No+Dry No.13 35 3.5 25 No+Dry No.14 20 7
Tool material grain size also had an evident effect on the cutting forces especially in the Fy direction.
As shown in Fig.5(b), the Fy value for the 35μm-grain-size tool was nearly two times bigger that that of 5μm-grain-size tool.
(a) Tool material (v=600m/min) (b) Tool grain size Fig. 5 The effect of tool matrix material and tool grain size on the cutting forces The Effect of Workpiece Materials.

AC impedance plots show that the conductivity is mainly due to the grain contribution which is evident in the enhanced short range diffusion of oxide ion vacancy in the grains with increasing temperature. 1.
Incorporation of vacancies in the vanadate layer may stimulate decrease in coordination number of vanadium cations from 6 to 4 or 5 that influences the stability limits and properties of the BIMEVOX polymorph modifications [38].
The values of angular frequencies at grain (ωg) and grain boundary (ωgb) are calculated from the frequency of the applied field at which the imaginary part of the impedance Z″ reaches a maximum according to equation (6): ωi = 2p fmax,i (6) where fmax,i is the frequency at maxima of the grain (i ≡ g) and in the grain boundary (i ≡ gb) semicircles respectively [59].
The higher frequency semicircle corresponds to the grain contribution to oxide ion conductivity whereas, the lower frequency semi circle is related to the grain boundary contribution to oxygen ionic conductivity.
It can be clearly observed that for all the compositions at a constant temperature (220°C), the values of grain resistance Rg are much higher than grain boundary resistance Rgb, suggesting the greater contribution of grain to the ionic conductivity than grain boundary.

The filling coefficient depends on the type of the material being transported and is determined according to the following informative criteria: · for lightweight and non-abrasive materials (e.g. flour, lime, corn), higher percentage of the cross-section filling can be proposed, up to 45%, and the number of revolutions can be increased, i.e. 2 ÷ 4 rev.s-1 · for materials which are either dusty, but yet abrasive (e.g. cement, dry sand) or non-abrasive, however, granular (e.g. fine-grained coal) it is necessary to decrease ψ to 30% by reducing the number of revolutions to 1 ÷ 2 rev.s-1, · for highly abrasive and lump materials, the trough capacity must be reduced to 15% and the revolutions minimize to 0.2 ÷ 1 rev.s-1.
ψ = 30% ψ = 15% Sm ψ = 45% Fig. 1 Utilization of the trough cross-section area with a different filling coefficient [4] An average speed v of the material conveyed in the trough is given by the product of the pitch s of the screw and the number of its revolutions n, i.e. v = s. n.
When selecting the number of revolutions it is important that the number of revolutions of the screw is lower than that of the so-called critical revolutions nkr, where centrifugal force acting on the material is equal to the weight of the material that results in the failure of the conveyor to operate.
L . w (10) where w is total , i.e. global friction factor, which takes the following reference values: § w = 1.8 for light, non-abrasive materials (flour, grain, pulses), § w = 3.1 for fine-grained and moderately abrasive materials (small sized coal), § w = 4.4 for coarse grained and highly abrasive materials (coke).
Calculation of power output: P = W (16) L = horizontal length 20 m w = coefficient of resistance (1.8 for fine-grained materials, flour, corn) The manufacturer defines P = 0.75 kW = 750 W, thus good agreement (for w = 1.8).

Table 1 shows ionic radii versus coordinate number (CN) [11].
This suggests that a small number of Ce ions in CaCe55 entered Ba sites as Ce3+.
CaCe55 and CeCa5A exhibit larger grain size (6 μm and 3 μm).
The fine-grained CeCa5 (0.8 μm) and coarse-grained CeCa5A further clarifies that no Ca2+ ions enter Ti sites in CeCa5A, while a small number of Ca2+ ions are incorporated completely into Ti sites in CeCa5.
The feature of layered domain grains of CaCe55 also suggests the mixed-valence site occupations by both dopants.

The sintered alloy consisted of submicrometer-sized grains.
Therefore, κ was reduced by the increase in the number of grain boundaries, and then thermoelectric performance was improved.
In order to control the conduction type as a p-type, additional element, which has the lower valence electron number, should be injected.
Figures 2a) and 2b) portray that the Fe2VAl0.97Sb0.03 and the Fe2V0.84Ti0.16Al0.97Sb0.03 sintered alloy consist of the same order of submicrometer-sized grains.
For the Sb-substituted Fe2VAl system, electrons can be injected because the number of valence electrons of Sb is larger than that of Al.

From the valence electron theory of Engel and Brewer of crystal structures for metals, the number of valence electrons, V, is 3 for FCC, 2 for HCP and 1 for BCC [4-6].
The data are taken from a number of investigators [2].
Dislocation nucleation and propagation leads to fine grains and subgrains/cells.
This is because the grain boundary has a diminishing effect on the strength as the grain size is decreased below about 2 PµPm.
The explanation is that grain boundary instability by sliding occurs at small grain sizes leading to inability of dislocations to pile-up at the grain boundary that gives the boundary its strength.

Herein, a number of paradigmatic multiscale models that attend the investigation of biological systems and the engineering of bioartificial systems is reviewed and discussed.
This modeling strategy allowed to reproduce the mechanics of F-actins and MTs, in terms of bending, stretching and torsional stiffness, with a very high level of accuracy, taking into account the contribute of the entire number of residues and using full atomistic models, with no need to introduce empirical parameters.
Crosslinked actin networks were studied by Kim and co-workers [7] using BD simulations combined with coarse-graining procedures, in which cylindrical segment represented several monomers of F-actin.
Atomistic level MD were combined with coarse grained simulation, allowing to identify links between IF structure and deformation mechanisms at distinct hierarchical levels.
At the molecular level, the contributions to the free energy variation coming from a number of interactions within DNA molecules, such as electrostatic interactions, biomolecule conformational entropy, internal energy variation, and hydration forces, were evaluated by means of MD simulations.

The contact stiffness can be obtained by number of contacting abrasive grains with workpiece and the support stiffness of a single abrasive grain kgs as shown in figure 2.
Therefore, the contact stiffness Kcon can be calculated by the contact length lc, the number of cutting points per unit area on the wheel surface n and grinding wheel width b as follow [2]
(4) lc kgs Grinding wheel Abrasive grain Workpiece Fig. 2 Schematic diagram of contacting abrasive grains with workpiece From this contact stiffness value and the normal grinding force Fn, the elastic deformation of the grinding wheel dcon can be obtained from (5) Amount the table floats ht can be calculated by following equation obtained by experiment
Therefore, repeating the calculation using equation(2) for each pass until the ground depth of cut is equal to the applied depth of cut, grinding operation number or grinding time can be obtained.
Table 1 Grinding condition Grinding machine Okamoto Surface grinder PSG-52AN Grinding wheel WA60J6B, f200 x f50.8 x 25 Workpiece NAK55 Peripheral speed 1800 [m/min] Dressing lead 0.5 [mm/rev] Ground passed time 5 passed times 10 passed times Table feed speed 3.1 [m/min] 3.1 [m/min] Applied depth of cut 8.24 [mm] 8.93 [mm] Stiffness of grinding machine 42.3 [N/mm] Support stiffness of a single abrasive grain 0.37 [N/mm] Number of cutting points per unit area 3 [points/mm2] Fig. 4 Measured results of normal grinding force Force sensor Grinding wheel Workpiece Table Fig. 3 Schematic diagram of surface grinding Number of grinding wheel passed the workpiece is defined as a passed time in this study.

Thus, it is calculated as: αBa2+ = 1.88 × 10-40 F·m2, αTi2+ = 0.30 × 10 -40 F·m2, αO2- = 3.07 × 10 -40 F·m2 And total polarizability of electronic displacement, αe, in a formula of Ba2Ti9O20 is as follows αe = ∑nkαk = 2αBa2+ + 9αTi2+ + 20αO2- = 67.84 × 10-40 F·m2 (2) where nk is the number of k-th ion and αk is the polarizability of electronic displacement of k-th ion in Ba2Ti9O20.
And P is the polarization strength of dielectric, which can be written as following P = (ε∞ -1) ε0 E = ∑ Nk αk Ei (4) where Nk is the number of k-th ion in unit volume and ε∞ is the dielectric constant of electronic displacement polarization.
(ε∞ -1) / [ γ(ε∞ -1) + 3] = ∑ Nkαk / (3ε0) = N ∑ nkαk / (3ε0) (5) where nk is the number of k-th ions in the formula and N is the number of molecules in a unit cell.
Vi = n Vo / Vc (8) Here, n is the number of TiO6 octahedron in an unit cell, Vo is the volume of a TiO6 octahedron, and Vc is the volume of a unit cell in Ba2Ti9O20.
ε = Vi εi + (1-Vi) εBa-O = 0.23×150+(1-0.23)×9=41.43 (9) As the diameter of grain in practical ceramics is around several micro-meters and the thickness of grain boundary is about a few of nano-meters, thus the volume ratio of grain boundary in ceramics turns out to be about 2%, with dielectric constant less than 5 for amorphous region of grain boundary.