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In this study, the tungsten trioxide (WO3) was used as an electrochromic layer because it exhibits electrochromic properties, since it is a semiconductor as changes color from clear to dark blue that changes the WO3 oxidation number from 6+ to 5+ state when applied to a potential [2].
Average grain sizes of all films can be calculated from Scherrer’s formula expressed in Eq. 1 (a) (c) (b) Fig. 1 The XRD patterns of (a) WO3 film (b) WO3/5 wt.
d=Kλβcosθ (1) where, d is the grain size, K is the shape factor, λ is the X-ray wavelength of Cu Κα(0.154 nm), β is the full-width at half maximum (FWHM) and θ is the Bragg angle.
The grain size of LiV2O5 doped WO3 film are 8.7 nm and 16.7 nm.
LiV2O5 film had good reversibility, which it is consistent with the more surface roughness, a large grain size and a wide CV loop.

During constant current TIG welding on aluminium [8] and its composites [9], weld strength is reduced due to higher heat input and lesser cooling rate of weld pool which results in coarse grain structure in weld zone and induces thermal stresses in heat affected zone.
The problem of coarse grain microstructure during TIG welding on aluminium alloys could be rectified by using surface nucleation, microcooler addition [8], arc oscillation [11] and pulsing current methods [12] so as to obtain fine grain microstructure.
Banwati, Jaswanti, 2013, An Analysis of Mechanical Properties of the Developed Al/SiC MMC's, American Journal of Mechanical Engineering, Volume 1, Number 1, pp 14-19.
Prasad Rao, 2005, Grain refinement through arc manipulation techniques in Al-Cu alloy GTA welds, Materials Science and Engineering A, 404, pp 227 - 234.

The amount of strain was controlled by the numbers of passes.
With increasing numbers of ECAP passes, the fraction of shear bands was increased.
Equal-channel angular pressing (ECAP) is a simple process to introduce large plastic strains [1] and to produce submicron-grained structure, which requires a block with two intersecting channels of identical cross-sections [2].
The imposed strain was controlled by applying different numbers of ECAP passes.

When the value of the flow velocity = 4.5m∙s-1 and the number of turns of the anode 90 rpm-1.
The current output increases from 0.72 to 0.94 when the values of the electrolyte flow rate = 2 m∙s-1 and the number of turns of the anode n=40 rpm∙min-1 are reached.
At the same time, the coatings were very fine-grained and had a shiny milky-gray smooth surface.
In this case, the coatings from fine-grained and dense gradually turn into more coarse-grained and rough with a large number of pores, due to the rapid release of hydrogen.
Increasing temperature usually reduces cathodic polarization, contributing to the formation of coarse-grained coatings.

The films annealed at 400℃ reveal only surface features in the range of 50 nm or less, suggesting the presence of a large number of crystallization centers.
However, the films annealed at 650℃ show well defined grains with parallel martensitic variants.
The grains are not uniform in size, ranging from 0.5 to 2 µm.
Grains of various diameters in the order of 0.5-2 µm indicating martensitic twin variants were obtained after annealing at 650℃ whereas annealing at 400℃ reveals nanocrystals in the order of 20-50nm diameter [4].

Fig.3 The picture of SEM-EDS for pit area of radiator pipe inner surface Fig.4 The picture of SEM-EDS for no pit area of radiator pipe inner surface Figure 3 and figure 4 show in addition to its own aluminum element of the aluminum alloy radiator, a large number of oxygen has been detected in pitting hole area of Radiator pipe inner surface, oxygen is derived from the dissolved oxygen in the cooling liquid, pit color area has much more oxygen than the color area with pit.
For aluminum alloy, Cl-, S2-in the external environment will react along the grain boundary, and their ability to drill seam is strong.
In general, after the corrosion elements open the grain boundary along the tip of the grain boundary, unprotected substrate will have oxidizing reaction immediately .Its anticorrosion performance degenerate.

It was found that the particles had hundreds nano-meter in size and most part of them were formed at the grain boundary.
Si3N4 particles and Mo5Si3 generated in Si3N4 grains and grain boundary were checked.
Ball Milling Si3N4, Al2O3, Y2O3 Spay Dry (Oxidation) Form MoO3 Sintering at N2,1850 ͠ Infiltration (Mo Solution) Calcination at 1450 ͠ Forming Ball Milling Si3N4, Al2O3, Y2O3 Spay Dry (Oxidation) Form MoO3 Sintering at N2,1850 ͠ Infiltration (Mo Solution) Calcination at 1450 ͠ Forming Journal Title and Volume Number (to be inserted by the publisher) Figure 2 X-ray diffraction pattern of fine particles reinforced Si3N4.

Many researchers have made a large number of experimental study on ultrasonic vibration assisted grinding, and gotten the conclusions that during ultrasonic vibration assisted grinding (UAG), grinding force was decreased, the machining quality was improved, and the material removal rate was increased[2,3,4,5], the kinematics characteristics of TUAG have not been analyzed in details.
The whole grains, a little broken grain and abrasive dust are found in the fractured zone.
Ductile grinding track and few whole grains are found in the fractured zone.

Initially we can verify that the material as received presents a ferritic microstructure consisting primarily of grains of various sizes (F) and grain boundaries slightly enriched by pearlite (P), as shown in figure (4a).
The good mechanical properties found are assigned to the refined microstructure, which hinders the propagation of cracks due to the presence of a large number of ferritic grains per unit length [5,7].

In order to improve their properties, we investigated the effect of grain size on thermal conductivity of these dual-site doped ZrNiSn-based half-Heusler alloys prepared by combing ball-milling and spark plasma sintering technique.
It was reported that nanostructured bulk materials of BixSb2-xTe3 showed high thermoelectric performance, which resulted from increased phonon scattering by grain boundaries and defects caused by hot pressing nanopowders ball-milled from crystalline ingots[2].
Enhanced phonon scattering by the grain-boundaries, which were greatly increased with decreasing the particle size was expected to reduction lattice thermal conductivity of our samples.
The contribution from carriers κc is related with the electrical resistivity ρ by Weidemann-Franz law κc = L T/ρ, L is Lorenz number.