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The effect of electrodeposition technology on particles content in the coating According to electrodeposition theories, a stronger cathode polarization causes a faster crystal nucleation rate and increased number of nuclei.
Compared with direct current electrodeposition [23,6], the composite coatings obtained by pulse electrodeposition (PED) showed more compact surfaces and less grain sizes, whereas those obtained by direct current electrodeposit have rougher surfaces and bigger grain sizes.
Fafeng Xia etc. [24]studied the effect of pulse current on the nucleation and growth of grains.
The size of nickel grain decreases with on-duty ratio of pulse current decreasing and pulse current density increasing.
The composite coatings obtained by pulse electrodeposition (PED) showed more compact surfaces and less grain sizes.

The number of elements used for simulation is about 270,000.
The first step of aging is to form carbides at the grain boundaries, and the second step of aging is to form γ' precipitates [2].
The base metals consist of a uniformly distributed γ' precipitates in the γ matrix along with metal carbides at the grain boundary.
An increase in hardness was explained due to the combined effect of the formation of larger γ' precipitates in the matrix and Cr rich carbides at grain boundaries, and MC carbides at intergranular and transgranular regions.
Cr rich grain boundary carbides and random distribution of MC carbides were formed in the HAZ.

(4) Where Dhkl means the average diameter of crystalline grain in (h k l) diffraction direction.
The variation of grain sizes is shown in Table 2.
In addition, it is easy to figure out from the SEM images that the grain size of nanoparticles is increased to about 150- 200 nm and the number of pinholes is decreased after annealing at 500 ˚C for 2 h.
Compared with the average nanocrystallite size estimated by Scherrer Equation, the grain size is much larger.
With the concentration of sodium citrate increasing, the crystalline grain size is decreased and the crystallization becomes better.

In order to improve thermal and physical properties of sialons, number of different additive alone or in combination [13-15], and heat treatment process have been used to synthesis of silicon based ceramics [16].
It was demonstrated that the elongated grains give better mechanical properties.
As seen from Fig. 4b there is well grain enlargement which indicates that with increasing liquid phase, the grain growth occurs.
Besides the liquid phase formation the sintering parameters were also affect the formation of a-sialon grains.
In longer holding time, larger grains were observed in the sintered samples.

The aspect ratio of the recrystallized grains of the sample without solution heat treatment is higher, Fig. 8 and 9(b), (c).
They found out that when their alloy was annealed at low temperatures, precipitation occurred along the grain boundaries which prevented recrystallization for happening.
Grains with substructures are not found in this sample which means that recrystallization had completed.
The retained rolling texture components for the sample which was solution heat treatment and annealed at 450 oC comes from the recovered grains.
Acknowledgements Part of this work was supported by a HKSAR RGC grant number HKU/7342/01E.

The austenite nucleation rate in this region is increased by the action of grinding force, and the austenite grains are broken to pieces.
The dislocations promote the nucleation of martensite and restrain the growing velocity of grains at the same time.
Therefore, the number of austenite nucleation is maximum, the broken degree is most obviously and the density of dislocation is largest.
The cooling speed at the shallow surface is a little slower than that at the outer surface, which promotes the growing of austenite grain; the grinding force is also smaller than that at the outer surface, thus the effect of broken force on grain is weakened.
In the inner layer, the highest temperature is lower than the other two parts’ during the grinding process, the driving force of phase transition is descended; the growing velocity of austenite grains is lowered accordingly; at the same time, the broken effect of grinding force on grains is weakened; thus the austenite grains formed is smaller than that at the shallow surface layer and the microstructure of martensite formed is finer accordingly.

The results indicate that the model has reliability on the prediction of surface roughness, abrasive belt grinding pressure has certain influence on the surface roughness, and grain size of belt and the belt linear speed have high significant influence on surface roughness and the influence coefficient are -0.9378 and -0.2317.
Test piece material is titanium alloy, belt by German VSM company silicon carbide abrasive belt KK718 , grain sizes were 240, 400, 600 and 800.
Through the test data and the above equation can be calculated ，， Using F test, there are (13) In the formula: “n” was the experimental group number, n=16; “P” is the number of variables, 。
We can from the following four diagram visually observed that the abrasive grains and the abrasive belt speed have great influence on surface roughness, but grinding pressure and contact hardness of wheel have little influence .

We employed a gold target with an extra purity to ablate the Nano-particles and a removal of tattoo Nd:YAG Q switching pulsed laser with a 10 Ns duration of pulses, the energy are 1000 mJ, the number of pulses are 600 pulses, and a frequency of 3 Hz to explore the gold NPs' characteristics using TEM and AFM.
Results and Discussion Figures (1) show the AFM images of gold NPs produced at 532 nm as called the second harmonic generation of pulsed (Nd-Yag) laser with its two- and three-dimensional, and it is clear that a high, consistent distribution and small grain size was achieved compared to the grain size of the gold nanoparticles that It was manufactured using the main wavelength of (Nd-Yag) laser (1064 nm).
The average diameter of the gold nanoparticles is 45.32 nm and also shows higher roughness due to the inverse relationship between grain size and surface roughness, and this result is completely identical to what was presented in previous results [45].
Figures (2) show the AFM images of gold NPs produced at 1064 nm as the main wavelength of the pulsed ND-Yag laser with its two- and three-dimensional dimensions, and it is clear that a high and consistent distribution and small grain size is achieved, but it is larger than that when compared to the grain size for gold nanoparticles that were synthesized by the mode of generation by the second harmonic (0.532µm) of Nd-Yag laser.
Figures (3 and 4) show the graph of the results of AFM images of gold nanoparticles that were produced at two wavelengths which are the 1.064 µm as it is called the main mode (wavelength) of pulsed Neodymium Yag laser and the generation by second harmonic of the Nd-Yag laser (o.532 µm), and it is clear from the graph The graph below shows that the gold nanoparticles obtained by using the second harmonic generation of the button have a very high uniform distribution that takes the form of a half sine wave or an elliptical curve, while the graph shows a high irregularity of the grain size of the gold nanoparticles obtained by using the prime wavelength of the laser pulsed, and this result is completely identical to what was presented in previous results d [48, 49].

Sandstones and siltites are medium and fine-grained (predominant grain size is 0.1-0.25 mm and 0.01-0.1 mm acc. to grain-size analysis) cemented by clay-carbonate cement.
Sand stones are grey, medium and small-grained, aleuritic to various degrees, micaceous, strong, and irregularly enriched with alluvions of coal-clay materials and interlays of clay materials.
Calcite inclusions are disorderly dispersed throughout the entire rock mass, cement 2-3 to 10-15 fragmentary grains and have no significant effect on porosity and permeability properties.
The analysis of texture-structural attributes and grain size composition of sediments shows that predominantly small-grain sediment was deposited within the field, sorted to a medium degree, with an increased content of loamy material having irregularly cluster-like distribution.
When the grain size decreases along with the general structural maturity of rocks, the number and radius of corrosion-expanded pores in them is decreased and the degree of their connectivity is reduced.

Grain expansion occurs at very high temperatures of 1200 – 1500 °C by means of which closed grains are formed – pellets sized 0.03 to 2 mm.
The structure of the grains thus produced is highly porous, has firm structure which prevents breaking when mixed.
This effect was predictable in the case of the fly ash and the character of the grains.
Registration number: CZ.1.07/2.3.00/20.0111, funded by European Social Funds, Operational program Education for Competitiveness.