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Both are having polygonal grains and the average grain size is calculated to be 0.5µm for microparticles and 55nm for nanoparticles from the SEM micrograph.
Where Rg, Rgb, and Rin represent grain, grain boundary, and interface resistances.
Nanoparticles have a considerable high value of impedance at every isothermal count due to the presence of the more number of resistive grain boundaries [3]. 3.5 Dielectric Studies The dielectric constant (εʹ) is estimated from the equation εʹ = Cp/C0, where C0 = ϵ0A/d. ϵ0 is the free space permittivity, A is the cross-sectional area of the pallet sample, and d is the thickness of the pallet.
In the event of nanoparticles, the σdc and ωp found to be comparatively low due to the presence of more number of resistive grain boundaries.
Impendence study reveals high grain boundary contribution present in nano form as compared to the micro.

It is known the increase of the wheel speed leads to the increase of the working grains, the number of grinding grains acting as rubbing and ploughing will increase, and then the friction in the contact zone will be intensified.
In this study, the grinding wheel is approximated as a cylindrical milling cutter with a large number of cutting edges, as shown in Fig.4.
(b) Up grinding (a) Down grinding Fig.4 Wheel-workpiece engagement in grinding The motion path of grains for the down grinding is shorter than that for the up grinding, thus the single grain average undeformed chip of the former is thicker than that of the latter.
Furthermore, it appears cutting interrupt which is caused by grains fracture, and leaves some scallops on the workpiece surface.
It leads the workpiece material to weld with grains.

It is apparent that quasi-isotropic spatial compensation of elastic stresses was reached by coordinated deformations among a large number of neighbouring nanograins.
In grains larger than 100 nm, martensite transformations are accompanied by the formation of one pack of nanotwinning in a grain Table 1.
Martensite transformations in Ti49.4Ni50.6 alloy depending of grain size Grain size martensite transformations structural mechanism transformations < 20 nm None!!!
- 20-50 nm B2↔ R single crystals B2 ↔ single crystals R 50-80 nm B2↔R↔ B19' single crystals B2 ↔ single crystals B19' > 80 nm B2↔R↔ B19' formation of one pack of nanotwinning in a grain Coarse grain B2 ↔ B19' formation of multi-packs of twins As shown, ECAP resulted in eguiaxed grains with a mean grain size of 200-300 nm [6].
The increase in the number of ECAP passes leads to strength enhancement due to the formation of a more refined structure.

It is total value of all pulse duration (ton): teff=ton∙Npulses, where Npulses – number of cycles per full electrodeposition time.
The grains of the DC, LP and MP films grew in the form of dendrites.
The average size of grain is reduced from 15 nm for DC film to 1.5 nm for SP film.
The size of the individual grains is determined by the pulse duration.
The LSF decreases simultaneously with the decreasing average grain size and thee increase in the proportion of the grain surface in comparison with the volume.

The nodular structure were built up by a great number of spheroids with different diameters.
ImageJ software was used to analysis the grain size distribution.
A number of publications reported that the carbon element co-deposited with chromium to form Cr-C from the trivalent chromium bath [5, 7, 11-15].
The surface roughness and the grain size decreased as shown in Figure 5 (b).
The SEM image showed a chromium matrix with a finer grain surface morphology and smaller grain sizes, which the average grain sizes of Cr coating has decreased to 1.962 μm.

The grain size was calculated according to the line intercept method using the following equation: D=LtP M D=Grain Size Lt=Total length × The number of the lines (Vertical/Horizontal) P=Number of grain boundry intercepts M=Optical Magnification If, |Horizontal D-value − Vertical D-value | < 5 The D-value is Averaged |Horizontal D-value − Vertical D-value | ≥ 5 The D-value is established as follows: Horizontal D-Value × Vertical D-Value Charpy impact (CI) testing was performed to determine the toughness of the rolled bars.
Single D values indicate an equiaxed grain shape and two numbers indicate an elongated grain shape.
The grain size of LE sections is 45 μm.
Again, hot rolling the samples at greater than 80% reduction in area causes elongated grains.
The side (End) sections of the three hot rolled bars have fine equiaxed grains.

The sintered materials were rather dense and showed preferred grain orientation.
The grain orientation degree and bending strength have also been investigated.
The grain orientation degree of the sintered materials was investigated by X-ray diffraction (XRD, Rigaku, Rint2000).
It indicates that the c-axis of the grains are preferentially oriented parallel to the pressing direction.
The sample number 1, 2 and 3 are corresponding to those sintered with different TeI4 content of 0.13%, 0.14% and 0.15% in weight, respectively.

There were a number of parameters that were adjusted in the electrodeposition process to control the characteristics and thickness of the deposited copper layer.
The whole surface was impacted with a large number of shots in a short period of time as the result of the high frequency vibration.
The number of samples prepared for this test is 7 samples for each parameter, the purpose of which was to obtain valid results.
The comparison of the mechanical properties of the nanostructured Cu with different treating methods and that of coarse-grained copper is shown in Table 2 [5-9].
The data is for Copper of conventional, ultrafine and nanocrystalline grain size, and after cold rolling to various degrees of Cold work [5 - 9].

Fig.3. shows the effect of the number of spin-coating and the annealing temperature on sheet resistance of 10 wt% Sn-doped ITO films.
Fig.3(a) Sheet resistance of the ITO films decreases by increasing number of spin coating (4 to 5 times).
The influences of the sequential annealing process could be revealed in the grain size and surface morphology.
(b) shows rectangular grains sporadically grown in AFM surface morphology.
Surface morphologies of ITO films revealed some dissimilar features in the view of the grain size and surface roughness by the annealing processes and gases.

However, a great number of σ precipitates can be observed in the bright field TEM.
There exist a large number of GP zones and a small amount of fine T1 phase also precipitates.
It was not reported that a large number of σ precipitate in Al-Cu-Li alloy.
Fig.14 shows the microstructures in the area of grain boundaries.
There exist a large number of equilibrium phases.