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Table 1 The spraying parameters of the NiCrAlY coatings Serial number Current (A) Voltage (V) Spray distance (mm) Feed interval(mm) Primary gas (Ar),slm Secondary gas (H2),slm Scan speed (mms-1) Beam size (mm) Laser power (W) L1 470 65 100 2 60 2 290 Φ 3 1500 L2 470 65 100 2 60 2 290 Φ 3 2000 L3 470 65 100 2 60 2 290 Φ 3 2500 L4 470 65 100 2 60 2 290 Φ 3 3000 Microstructural characterization and the porosity of NiCrAlY coatings were studied using an optical microscope.
When the laser power arrived at 2500W, some pores were still observed, nevertheless their number was largely decreased and the coating achived metallurgy bonding entirely which can be seen in fig.1c.
(Fig.2) a） (Fig.3) a） Fig.2 Porosity of the LHPS NiCrAlY coating with different laser power (L1)1500W;(L2)2000W;(L3)2500W;(L4)3000W Fig.3 Micro-hardness of the LHPS NiCrAlY coating(L1)1500W;(L2)2000W;(L3)2500W;(L4)3000W Table 2 The bonding strength of the coatings Coating number Loading（KN） Bonding strength （MPa） 1 2 3 L1 15.88 20.84 21.78 33 L2 24.32 21.86 21.63 48 L3 41.26 45.71 42.65 87 L4 10.34 8.63 9.51 20 Table 2 gives the bonding strength of the LHPS NiCrAlY coatings with the laser power of 1500W,2000W,2500W and 3000W respectively.Firstly, with the increasing of the laser power from 1500W to2500W, the coatings’ bonding strength are rising gradually,and this is because the laser power assist the plasma beam to melt the spraying powders and coatings farther in the LHPS processing and the spraying powders could not be melted adequately until the laser power arriving at 2500W(which can be seen in fig.5).
（d） a） （a） a） （c） a） （b） a） Fig.4 Photographs of the corrosion area of the coatings after 96 hours of NSS test with different laser powers (a)1500W(b)2000W(c)2500W(d)3000W Table 3 The corrosion area of the surface coating after 96 hours of NSS test Coating number L1 L2 L3 L4 Corrosion area (the proportion to the whole coating) 1/2 1/3 one point 2/3 （b） a） （a） a） （d） a） （c） a） Fig.5 SEM configuration of the spraying powders on the surface coating depostited by diffferent laser power in LHPS processing (a)1500W (b)2000W (c)2500W(d)3000W The Fig.5 gives the SEM configuration of the spraying powders on the surface coating deposited by diffferent laser power in LHPS processing and which further demonstrates that how the laser powers affect the coatings’ microstructures.We can see that the melting state of the powders are changed following different laser power, when it is 2500W, the spraying powders can be melted sufficiently
When the laser power is lower than 2500W, for example the 1500W and 2000W, many big grains of unmelted or mid-melted powders can be seen on the surface coating and which make the coating’s microstructure loose and exsit poor bonding strength(as is shown in fig.5a,b).This is because the laser density is too low to melt the spraying powders sufficiently, the laser irradiation area became solidify rapidly and many cracks and big pores are formed in the coating(fig.1 a,b).

Let us turn to formula (8), which describes the magnitude of the fluctuations of the number of nuclei.
Calculating the number of these nuclei and predicting their future lives is the purpose of the kinetic theory of new phase nucleation.
The quantity i is understood here as the number of structural units of the old phase.
Let the temperature , and (i.e. the pore is semi-spherical and form on the boundary grain).
Rice, et al., Non-equilibrium models for diffusive cavitation of grain interfaces, Acta Met. 27 (1979) 265-284

Earlier, a number of bioglasses were created based on MgO–CaO–SiO2–P2O5–CaF2, Na2O–CaO–SiO2–P2O5, CaO–SiO2–P2O5, and CaO–SiO2–B2O3–P2O5 [1-3,6,7] to the matrices of which Fe3O4 particles were incorporated.
Mössbauer spectrum of a fine-grained Fig. 2.
This fact is confirmed by the data on the microstructure of the composite ceramics and elemental composition of regions in which ferrite particles and hydroxyapatite grains are concentrated (Figs.5 and 6).
Microstructure of the composite ceramics with an addition of 5 wt % BaO·6Fe2O3 and the elemental composition of regions in which (a) ferrite particles and (b) hydroxyapatite grains are concentrated.
The numbers in the upper part indicate the energy of irradiating electrons in keV.

According to Brinksmeier [10] the white layer is very fine-grained martensite (a-Fe peaks) in hypo-eutectoid steel, while in hypereutectoid steel it is mainly austenite (g-Fe peaks).
c) According to Klocke’s measurements [2] the white layer on mainly steels with C content consists of fine grains of ferrite of nanometer magnitude.
In recent years, besides measurements, a number of examinations have been carried out using FEM methods to determine the thickness of the white layer.
Its structure was examined with optical and electron microscope, and elongated grains were found.
According to the examination results, the specific friction edge output does not reveal anything about the thickness of the creating layer or its relative dispersion (R2≈0 and R2≈0.35, respectively).; no meaningful relationship between them can be discovered This, of course, can be the consequence of an insufficient number of experiments for making statistically backed statements.

As the NaCl grains dissolve through the leaching process, voids will be created within the specimens in the positions previously occupied by the NaCl grains, resulting the formation of the aluminum foam.
Specimens containing a greater proportion of NaCl, specifically 55 wt.%, will have the greatest number of voids, leading to increased porosity and reduced foam density.
Initially, the specimens were grinded with Sic papers of different grain sizes 180,400,800,100,1500,2000,3000 and 4000.
The main reason of this improvement is due to the additive occupied spaces within the crystal lattice of the base material and helped produce a structure of much denser and reduced the number of voids. making it more difficult for dislocations (defects in the crystal structure) to move.

The number of falls when the samples of both sides of the groove merged over a length of 1.5 cm and the water content at that time were recorded.
[d] Special soil is heated at high temperature[d] Obtained from the garden[d] The raw material from around the Sultan Qaboos Mosque in Salalah is taken → Crushed to large grains→ Soaked in water →Undesirable components removed as supernatant.
The grain size tends to be smaller in the order of joint material (khatri), wall-finishing material (nurah and 1-1k), and floor-finishing material (yeb').
This observation is in line with the results of the particle-size tests, and it is concluded that the coarse-grained nurah and yeb' are unable to retain water.
Acknowledgements This work was supported by the Japan Society for the Promotion of Science Fostering Joint International Research (B) Grant Number JP20KK0020.

Their excellent properties (significantly exceeding traditional hydrides) are a result of the combined engineering of many factors: alloy composition, surface properties, microstructure, grain size and others.
These measurements may supply useful indirect information about the influence of surface chemical composition, crystal structure and grain sizes on the hydrogenation properties of the studied materials.
Fig. 2 The discharge capacity as a function of cycle number for MA and annealed Mg2Cu (a), Mg2Ni (b) and Mg2Ni/Pd (c), Mg1.5Mn0.5Ni/C (d) and Mg1.5Al0.5Ni/Pd (e) electrodes (solution, 6 M KOH; temperature, 20o C).
Fig. 2 and Tables 1 and 2 show the discharge capacities as a function of the cycle number for studied nanocomposite materials.
Normally the interior of the nanocrystal is constrained and the distances between atoms located at the grain boundaries expanded.

Nowadays these two materials are of great interest for science and technology due to their exceptional characteristics: high thermal conductivity and at the same time high electrical resistance, high chemical inertness, high hardness and wear resistance and low friction coefficients, which make them appropriate for a number of technological applications, e.g. as protective optical or tribological coatings [3-5].
A number of important applications have been developed with a promising future.
It consists of equiaxed small grains near the substrate surface, causing the growth of columns as the layer thickness increases.
The mean grain size is 0.12-0.15 µm on the heated substrates, while on the cool substrates it is 0.09-0.10 µm.
The homogeneity of the grains is better on cool substrates.

Technology development and new grades of alloys creation put before construction materials the number of requirements in range of durability and reliability of created constructions.
Grain size obtained during deformation at 4800C is about 10 mm, which indicates the occurrence of dynamic recrystallization process. 3.

Numbers are impressive: considering as an example the mining sector and the stone industry, nearly the 80% of the mined material is waste [0].
Asdrubali and colleagues [49] investigated the thermal and acoustical performance of a panel composed by overlapping a variable number of cardboard layers.
Pisello and colleagues [50] assessed optic characteristics of five types of natural gravels, with different grain size and they were able to state that albedo is related to grain size, increasing with decreasing grain size, and reach good values for all the investigated gravels.
Table 3 Thermal-optic properties of natural gravels for cool roof application Name Employment Solar reflectance Albedo Thermal emittance Natural gravels with different grain size Horizontal Roof Urban paving 38-62% [0] In lab measured 36-44 [0] In field measured 0.9 [0] Figure 1: Surface temperature of five natural gravels (T1,T2,T3,T4 with decreasing grain size) during September(adapted from [0]).
Figure 2: Comparison of gravels (1,2,3,4 with decreasing grain size) daily maximum surface temperatures for September days (adapted from [0]).